Merge pull request 'add fee to builder' (#4) from lucretius/librustzcash:sdl into sdl

Reviewed-on: https://git.hush.is/hush/librustzcash/pulls/4

.gitlab-ci.yml

@@ -5,6 +5,7 @@
  #  Date: 9/10/2018
  #  Description:  Used to setup runners/jobs for librustzcash
  #  Usage: Commit source and the pipeline will trigger the according jobs.
+ #         For now the build and test are done in the same jobs.
  #
  #  Known bugs/missing features:
  #

.travis.yml

@@ -0,0 +1,13 @@
+language: rust
+rust:
+  - 1.36.0
+
+cache: cargo
+
+before_script:
+  - rustup component add rustfmt
+
+script:
+  - cargo build --verbose --release --all
+  - cargo fmt --all -- --check
+  - cargo test --verbose --release --all

Cargo.toml

@@ -1,13 +1,14 @@
 [workspace]
 members = [
     "bellman",
+    "ff",
+    "group",
     "librustzcash",
     "pairing",
-    "sapling-crypto",
+    "zcash_client_backend",
+    "zcash_client_sqlite",
     "zcash_primitives",
     "zcash_proofs",
-    "zcash_wallet",
-    "zip32",
 ]
 
 [profile.release]

LICENSE-MIT

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2017 Zcash Company
+Copyright (c) 2017-2019 Electric Coin Company
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

bellman/Cargo.toml

@@ -9,14 +9,30 @@ repository = "https://github.com/ebfull/bellman"
 version = "0.1.0"
 
 [dependencies]
-rand = "0.4"
 bit-vec = "0.4.4"
+blake2s_simd = "0.5"
+ff = { path = "../ff" }
 futures = "0.1"
-futures-cpupool = "0.1"
+futures-cpupool = { version = "0.1", optional = true }
-num_cpus = "1"
+group = { path = "../group" }
-crossbeam = "0.3"
+num_cpus = { version = "1", optional = true }
-pairing = { path = "../pairing" }
+crossbeam = { version = "0.3", optional = true }
+pairing = { path = "../pairing", optional = true }
+rand_core = "0.5"
 byteorder = "1"
 
+[dev-dependencies]
+hex-literal = "0.1"
+rand = "0.7"
+rand_xorshift = "0.2"
+sha2 = "0.8"
+
 [features]
-default = []
+groth16 = ["pairing"]
+multicore = ["futures-cpupool", "crossbeam", "num_cpus"]
+default = ["groth16", "multicore"]
+
+[[test]]
+name = "mimc"
+path = "tests/mimc.rs"
+required-features = ["groth16"]

bellman/src/domain.rs

@@ -10,29 +10,23 @@
 //! This allows us to perform polynomial operations in O(n)
 //! by performing an O(n log n) FFT over such a domain.
 
-use pairing::{
+use ff::{Field, PrimeField, ScalarEngine};
-    Engine,
+use group::CurveProjective;
-    Field,
-    PrimeField,
-    CurveProjective
-};
 
-use super::{
+use super::SynthesisError;
-    SynthesisError
-};
 
 use super::multicore::Worker;
 
-pub struct EvaluationDomain<E: Engine, G: Group<E>> {
+pub struct EvaluationDomain<E: ScalarEngine, G: Group<E>> {
     coeffs: Vec<G>,
     exp: u32,
     omega: E::Fr,
     omegainv: E::Fr,
     geninv: E::Fr,
-    minv: E::Fr
+    minv: E::Fr,
 }
 
-impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
+impl<E: ScalarEngine, G: Group<E>> EvaluationDomain<E, G> {
     pub fn as_ref(&self) -> &[G] {
         &self.coeffs
     }
@@ -45,8 +39,7 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
         self.coeffs
     }
 
-    pub fn from_coeffs(mut coeffs: Vec<G>) -> Result<EvaluationDomain<E, G>, SynthesisError>
+    pub fn from_coeffs(mut coeffs: Vec<G>) -> Result<EvaluationDomain<E, G>, SynthesisError> {
-    {
         // Compute the size of our evaluation domain
         let mut m = 1;
         let mut exp = 0;
@@ -57,7 +50,7 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
             // The pairing-friendly curve may not be able to support
             // large enough (radix2) evaluation domains.
             if exp >= E::Fr::S {
-                return Err(SynthesisError::PolynomialDegreeTooLarge)
+                return Err(SynthesisError::PolynomialDegreeTooLarge);
             }
         }
 
@@ -76,17 +69,18 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
             omega: omega,
             omegainv: omega.inverse().unwrap(),
             geninv: E::Fr::multiplicative_generator().inverse().unwrap(),
-            minv: E::Fr::from_str(&format!("{}", m)).unwrap().inverse().unwrap()
+            minv: E::Fr::from_str(&format!("{}", m))
+                .unwrap()
+                .inverse()
+                .unwrap(),
         })
     }
 
-    pub fn fft(&mut self, worker: &Worker)
+    pub fn fft(&mut self, worker: &Worker) {
-    {
         best_fft(&mut self.coeffs, worker, &self.omega, self.exp);
     }
 
-    pub fn ifft(&mut self, worker: &Worker)
+    pub fn ifft(&mut self, worker: &Worker) {
-    {
         best_fft(&mut self.coeffs, worker, &self.omegainv, self.exp);
 
         worker.scope(self.coeffs.len(), |scope, chunk| {
@@ -102,8 +96,7 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
         });
     }
 
-    pub fn distribute_powers(&mut self, worker: &Worker, g: E::Fr)
+    pub fn distribute_powers(&mut self, worker: &Worker, g: E::Fr) {
-    {
         worker.scope(self.coeffs.len(), |scope, chunk| {
             for (i, v) in self.coeffs.chunks_mut(chunk).enumerate() {
                 scope.spawn(move || {
@@ -117,14 +110,12 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
         });
     }
 
-    pub fn coset_fft(&mut self, worker: &Worker)
+    pub fn coset_fft(&mut self, worker: &Worker) {
-    {
         self.distribute_powers(worker, E::Fr::multiplicative_generator());
         self.fft(worker);
     }
 
-    pub fn icoset_fft(&mut self, worker: &Worker)
+    pub fn icoset_fft(&mut self, worker: &Worker) {
-    {
         let geninv = self.geninv;
 
         self.ifft(worker);
@@ -143,9 +134,11 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
     /// The target polynomial is the zero polynomial in our
     /// evaluation domain, so we must perform division over
     /// a coset.
-    pub fn divide_by_z_on_coset(&mut self, worker: &Worker)
+    pub fn divide_by_z_on_coset(&mut self, worker: &Worker) {
-    {
+        let i = self
-        let i = self.z(&E::Fr::multiplicative_generator()).inverse().unwrap();
+            .z(&E::Fr::multiplicative_generator())
+            .inverse()
+            .unwrap();
 
         worker.scope(self.coeffs.len(), |scope, chunk| {
             for v in self.coeffs.chunks_mut(chunk) {
@@ -163,7 +156,11 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
         assert_eq!(self.coeffs.len(), other.coeffs.len());
 
         worker.scope(self.coeffs.len(), |scope, chunk| {
-            for (a, b) in self.coeffs.chunks_mut(chunk).zip(other.coeffs.chunks(chunk)) {
+            for (a, b) in self
+                .coeffs
+                .chunks_mut(chunk)
+                .zip(other.coeffs.chunks(chunk))
+            {
                 scope.spawn(move || {
                     for (a, b) in a.iter_mut().zip(b.iter()) {
                         a.group_mul_assign(&b.0);
@@ -178,7 +175,11 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
         assert_eq!(self.coeffs.len(), other.coeffs.len());
 
         worker.scope(self.coeffs.len(), |scope, chunk| {
-            for (a, b) in self.coeffs.chunks_mut(chunk).zip(other.coeffs.chunks(chunk)) {
+            for (a, b) in self
+                .coeffs
+                .chunks_mut(chunk)
+                .zip(other.coeffs.chunks(chunk))
+            {
                 scope.spawn(move || {
                     for (a, b) in a.iter_mut().zip(b.iter()) {
                         a.group_sub_assign(&b);
@@ -189,7 +190,7 @@ impl<E: Engine, G: Group<E>> EvaluationDomain<E, G> {
     }
 }
 
-pub trait Group<E: Engine>: Sized + Copy + Clone + Send + Sync {
+pub trait Group<E: ScalarEngine>: Sized + Copy + Clone + Send + Sync {
     fn group_zero() -> Self;
     fn group_mul_assign(&mut self, by: &E::Fr);
     fn group_add_assign(&mut self, other: &Self);
@@ -204,7 +205,7 @@ impl<G: CurveProjective> PartialEq for Point<G> {
     }
 }
 
-impl<G: CurveProjective> Copy for Point<G> { }
+impl<G: CurveProjective> Copy for Point<G> {}
 
 impl<G: CurveProjective> Clone for Point<G> {
     fn clone(&self) -> Point<G> {
@@ -227,23 +228,23 @@ impl<G: CurveProjective> Group<G::Engine> for Point<G> {
     }
 }
 
-pub struct Scalar<E: Engine>(pub E::Fr);
+pub struct Scalar<E: ScalarEngine>(pub E::Fr);
 
-impl<E: Engine> PartialEq for Scalar<E> {
+impl<E: ScalarEngine> PartialEq for Scalar<E> {
     fn eq(&self, other: &Scalar<E>) -> bool {
         self.0 == other.0
     }
 }
 
-impl<E: Engine> Copy for Scalar<E> { }
+impl<E: ScalarEngine> Copy for Scalar<E> {}
 
-impl<E: Engine> Clone for Scalar<E> {
+impl<E: ScalarEngine> Clone for Scalar<E> {
     fn clone(&self) -> Scalar<E> {
         *self
     }
 }
 
-impl<E: Engine> Group<E> for Scalar<E> {
+impl<E: ScalarEngine> Group<E> for Scalar<E> {
     fn group_zero() -> Self {
         Scalar(E::Fr::zero())
     }
@@ -258,8 +259,7 @@ impl<E: Engine> Group<E> for Scalar<E> {
     }
 }
 
-fn best_fft<E: Engine, T: Group<E>>(a: &mut [T], worker: &Worker, omega: &E::Fr, log_n: u32)
+fn best_fft<E: ScalarEngine, T: Group<E>>(a: &mut [T], worker: &Worker, omega: &E::Fr, log_n: u32) {
-{
     let log_cpus = worker.log_num_cpus();
 
     if log_n <= log_cpus {
@@ -269,8 +269,7 @@ fn best_fft<E: Engine, T: Group<E>>(a: &mut [T], worker: &Worker, omega: &E::Fr,
     }
 }
 
-fn serial_fft<E: Engine, T: Group<E>>(a: &mut [T], omega: &E::Fr, log_n: u32)
+fn serial_fft<E: ScalarEngine, T: Group<E>>(a: &mut [T], omega: &E::Fr, log_n: u32) {
-{
     fn bitreverse(mut n: u32, l: u32) -> u32 {
         let mut r = 0;
         for _ in 0..l {
@@ -292,36 +291,35 @@ fn serial_fft<E: Engine, T: Group<E>>(a: &mut [T], omega: &E::Fr, log_n: u32)
 
     let mut m = 1;
     for _ in 0..log_n {
-        let w_m = omega.pow(&[(n / (2*m)) as u64]);
+        let w_m = omega.pow(&[(n / (2 * m)) as u64]);
 
         let mut k = 0;
         while k < n {
             let mut w = E::Fr::one();
             for j in 0..m {
-                let mut t = a[(k+j+m) as usize];
+                let mut t = a[(k + j + m) as usize];
                 t.group_mul_assign(&w);
-                let mut tmp = a[(k+j) as usize];
+                let mut tmp = a[(k + j) as usize];
                 tmp.group_sub_assign(&t);
-                a[(k+j+m) as usize] = tmp;
+                a[(k + j + m) as usize] = tmp;
-                a[(k+j) as usize].group_add_assign(&t);
+                a[(k + j) as usize].group_add_assign(&t);
                 w.mul_assign(&w_m);
             }
 
-            k += 2*m;
+            k += 2 * m;
         }
 
         m *= 2;
     }
 }
 
-fn parallel_fft<E: Engine, T: Group<E>>(
+fn parallel_fft<E: ScalarEngine, T: Group<E>>(
     a: &mut [T],
     worker: &Worker,
     omega: &E::Fr,
     log_n: u32,
-    log_cpus: u32
+    log_cpus: u32,
-)
+) {
-{
     assert!(log_n >= log_cpus);
 
     let num_cpus = 1 << log_cpus;
@@ -375,19 +373,23 @@ fn parallel_fft<E: Engine, T: Group<E>>(
 
 // Test multiplying various (low degree) polynomials together and
 // comparing with naive evaluations.
+#[cfg(feature = "pairing")]
 #[test]
 fn polynomial_arith() {
     use pairing::bls12_381::Bls12;
-    use rand::{self, Rand};
+    use rand_core::RngCore;
 
-    fn test_mul<E: Engine, R: rand::Rng>(rng: &mut R)
+    fn test_mul<E: ScalarEngine, R: RngCore>(rng: &mut R) {
-    {
         let worker = Worker::new();
 
         for coeffs_a in 0..70 {
             for coeffs_b in 0..70 {
-                let mut a: Vec<_> = (0..coeffs_a).map(|_| Scalar::<E>(E::Fr::rand(rng))).collect();
+                let mut a: Vec<_> = (0..coeffs_a)
-                let mut b: Vec<_> = (0..coeffs_b).map(|_| Scalar::<E>(E::Fr::rand(rng))).collect();
+                    .map(|_| Scalar::<E>(E::Fr::random(rng)))
+                    .collect();
+                let mut b: Vec<_> = (0..coeffs_b)
+                    .map(|_| Scalar::<E>(E::Fr::random(rng)))
+                    .collect();
 
                 // naive evaluation
                 let mut naive = vec![Scalar(E::Fr::zero()); coeffs_a + coeffs_b];
@@ -422,13 +424,13 @@ fn polynomial_arith() {
     test_mul::<Bls12, _>(rng);
 }
 
+#[cfg(feature = "pairing")]
 #[test]
 fn fft_composition() {
     use pairing::bls12_381::Bls12;
-    use rand;
+    use rand_core::RngCore;
 
-    fn test_comp<E: Engine, R: rand::Rng>(rng: &mut R)
+    fn test_comp<E: ScalarEngine, R: RngCore>(rng: &mut R) {
-    {
         let worker = Worker::new();
 
         for coeffs in 0..10 {
@@ -436,7 +438,7 @@ fn fft_composition() {
 
             let mut v = vec![];
             for _ in 0..coeffs {
-                v.push(Scalar::<E>(rng.gen()));
+                v.push(Scalar::<E>(E::Fr::random(rng)));
             }
 
             let mut domain = EvaluationDomain::from_coeffs(v.clone()).unwrap();
@@ -460,25 +462,27 @@ fn fft_composition() {
     test_comp::<Bls12, _>(rng);
 }
 
+#[cfg(feature = "pairing")]
 #[test]
 fn parallel_fft_consistency() {
     use pairing::bls12_381::Bls12;
-    use rand::{self, Rand};
+    use rand_core::RngCore;
     use std::cmp::min;
 
-    fn test_consistency<E: Engine, R: rand::Rng>(rng: &mut R)
+    fn test_consistency<E: ScalarEngine, R: RngCore>(rng: &mut R) {
-    {
         let worker = Worker::new();
 
         for _ in 0..5 {
             for log_d in 0..10 {
                 let d = 1 << log_d;
 
-                let v1 = (0..d).map(|_| Scalar::<E>(E::Fr::rand(rng))).collect::<Vec<_>>();
+                let v1 = (0..d)
+                    .map(|_| Scalar::<E>(E::Fr::random(rng)))
+                    .collect::<Vec<_>>();
                 let mut v1 = EvaluationDomain::from_coeffs(v1).unwrap();
                 let mut v2 = EvaluationDomain::from_coeffs(v1.coeffs.clone()).unwrap();
 
-                for log_cpus in log_d..min(log_d+1, 3) {
+                for log_cpus in log_d..min(log_d + 1, 3) {
                     parallel_fft(&mut v1.coeffs, &worker, &v1.omega, log_d, log_cpus);
                     serial_fft(&mut v2.coeffs, &v2.omega, log_d);
 

bellman/src/gadgets.rs

@@ -1,23 +1,15 @@
-#[cfg(test)]
 pub mod test;
 
-pub mod boolean;
-pub mod multieq;
-pub mod uint32;
 pub mod blake2s;
-pub mod num;
+pub mod boolean;
 pub mod lookup;
-pub mod ecc;
+pub mod multieq;
-pub mod pedersen_hash;
 pub mod multipack;
+pub mod num;
 pub mod sha256;
+pub mod uint32;
 
-pub mod sapling;
+use crate::SynthesisError;
-pub mod sprout;
-
-use bellman::{
-    SynthesisError
-};
 
 // TODO: This should probably be removed and we
 // should use existing helper methods on `Option`
@@ -25,7 +17,7 @@ use bellman::{
 /// This basically is just an extension to `Option`
 /// which allows for a convenient mapping to an
 /// error on `None`.
-trait Assignment<T> {
+pub trait Assignment<T> {
     fn get(&self) -> Result<&T, SynthesisError>;
 }
 
@@ -33,7 +25,7 @@ impl<T> Assignment<T> for Option<T> {
     fn get(&self) -> Result<&T, SynthesisError> {
         match *self {
             Some(ref v) => Ok(v),
-            None => Err(SynthesisError::AssignmentMissing)
+            None => Err(SynthesisError::AssignmentMissing),
         }
     }
 }

bellman/src/gadgets/blake2s.rs

@@ -1,19 +1,10 @@
-use pairing::{
+use pairing::Engine;
-    Engine,
-};
 
-use bellman::{
+use crate::{ConstraintSystem, SynthesisError};
-    SynthesisError,
-    ConstraintSystem
-};
 
-use super::boolean::{
+use super::boolean::Boolean;
-    Boolean
-};
 
-use super::uint32::{
+use super::uint32::UInt32;
-    UInt32
-};
 
 use super::multieq::MultiEq;
 
@@ -65,7 +56,7 @@ const SIGMA: [[usize; 16]; 10] = [
     [12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11],
     [13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10],
     [6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5],
-    [10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0]
+    [10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0],
 ];
 
 /*
@@ -98,17 +89,30 @@ fn mixing_g<E: Engine, CS: ConstraintSystem<E>, M>(
     c: usize,
     d: usize,
     x: &UInt32,
-    y: &UInt32
+    y: &UInt32,
 ) -> Result<(), SynthesisError>
-    where M: ConstraintSystem<E, Root=MultiEq<E, CS>>
+where
+    M: ConstraintSystem<E, Root = MultiEq<E, CS>>,
 {
-    v[a] = UInt32::addmany(cs.namespace(|| "mixing step 1"), &[v[a].clone(), v[b].clone(), x.clone()])?;
+    v[a] = UInt32::addmany(
+        cs.namespace(|| "mixing step 1"),
+        &[v[a].clone(), v[b].clone(), x.clone()],
+    )?;
     v[d] = v[d].xor(cs.namespace(|| "mixing step 2"), &v[a])?.rotr(R1);
-    v[c] = UInt32::addmany(cs.namespace(|| "mixing step 3"), &[v[c].clone(), v[d].clone()])?;
+    v[c] = UInt32::addmany(
+        cs.namespace(|| "mixing step 3"),
+        &[v[c].clone(), v[d].clone()],
+    )?;
     v[b] = v[b].xor(cs.namespace(|| "mixing step 4"), &v[c])?.rotr(R2);
-    v[a] = UInt32::addmany(cs.namespace(|| "mixing step 5"), &[v[a].clone(), v[b].clone(), y.clone()])?;
+    v[a] = UInt32::addmany(
+        cs.namespace(|| "mixing step 5"),
+        &[v[a].clone(), v[b].clone(), y.clone()],
+    )?;
     v[d] = v[d].xor(cs.namespace(|| "mixing step 6"), &v[a])?.rotr(R3);
-    v[c] = UInt32::addmany(cs.namespace(|| "mixing step 7"), &[v[c].clone(), v[d].clone()])?;
+    v[c] = UInt32::addmany(
+        cs.namespace(|| "mixing step 7"),
+        &[v[c].clone(), v[d].clone()],
+    )?;
     v[b] = v[b].xor(cs.namespace(|| "mixing step 8"), &v[c])?.rotr(R4);
 
     Ok(())
@@ -162,15 +166,13 @@ fn mixing_g<E: Engine, CS: ConstraintSystem<E>, M>(
        END FUNCTION.
 */
 
-
 fn blake2s_compression<E: Engine, CS: ConstraintSystem<E>>(
     mut cs: CS,
     h: &mut [UInt32],
     m: &[UInt32],
     t: u64,
-    f: bool
+    f: bool,
-) -> Result<(), SynthesisError>
+) -> Result<(), SynthesisError> {
-{
     assert_eq!(h.len(), 8);
     assert_eq!(m.len(), 16);
 
@@ -196,10 +198,16 @@ fn blake2s_compression<E: Engine, CS: ConstraintSystem<E>>(
     assert_eq!(v.len(), 16);
 
     v[12] = v[12].xor(cs.namespace(|| "first xor"), &UInt32::constant(t as u32))?;
-    v[13] = v[13].xor(cs.namespace(|| "second xor"), &UInt32::constant((t >> 32) as u32))?;
+    v[13] = v[13].xor(
+        cs.namespace(|| "second xor"),
+        &UInt32::constant((t >> 32) as u32),
+    )?;
 
     if f {
-        v[14] = v[14].xor(cs.namespace(|| "third xor"), &UInt32::constant(u32::max_value()))?;
+        v[14] = v[14].xor(
+            cs.namespace(|| "third xor"),
+            &UInt32::constant(u32::max_value()),
+        )?;
     }
 
     {
@@ -210,20 +218,92 @@ fn blake2s_compression<E: Engine, CS: ConstraintSystem<E>>(
 
             let s = SIGMA[i % 10];
 
-            mixing_g(cs.namespace(|| "mixing invocation 1"), &mut v, 0, 4,  8, 12, &m[s[ 0]], &m[s[ 1]])?;
+            mixing_g(
-            mixing_g(cs.namespace(|| "mixing invocation 2"), &mut v, 1, 5,  9, 13, &m[s[ 2]], &m[s[ 3]])?;
+                cs.namespace(|| "mixing invocation 1"),
-            mixing_g(cs.namespace(|| "mixing invocation 3"), &mut v, 2, 6, 10, 14, &m[s[ 4]], &m[s[ 5]])?;
+                &mut v,
-            mixing_g(cs.namespace(|| "mixing invocation 4"), &mut v, 3, 7, 11, 15, &m[s[ 6]], &m[s[ 7]])?;
+                0,
+                4,
+                8,
+                12,
+                &m[s[0]],
+                &m[s[1]],
+            )?;
+            mixing_g(
+                cs.namespace(|| "mixing invocation 2"),
+                &mut v,
+                1,
+                5,
+                9,
+                13,
+                &m[s[2]],
+                &m[s[3]],
+            )?;
+            mixing_g(
+                cs.namespace(|| "mixing invocation 3"),
+                &mut v,
+                2,
+                6,
+                10,
+                14,
+                &m[s[4]],
+                &m[s[5]],
+            )?;
+            mixing_g(
+                cs.namespace(|| "mixing invocation 4"),
+                &mut v,
+                3,
+                7,
+                11,
+                15,
+                &m[s[6]],
+                &m[s[7]],
+            )?;
 
-            mixing_g(cs.namespace(|| "mixing invocation 5"), &mut v, 0, 5, 10, 15, &m[s[ 8]], &m[s[ 9]])?;
+            mixing_g(
-            mixing_g(cs.namespace(|| "mixing invocation 6"), &mut v, 1, 6, 11, 12, &m[s[10]], &m[s[11]])?;
+                cs.namespace(|| "mixing invocation 5"),
-            mixing_g(cs.namespace(|| "mixing invocation 7"), &mut v, 2, 7,  8, 13, &m[s[12]], &m[s[13]])?;
+                &mut v,
-            mixing_g(cs.namespace(|| "mixing invocation 8"), &mut v, 3, 4,  9, 14, &m[s[14]], &m[s[15]])?;
+                0,
+                5,
+                10,
+                15,
+                &m[s[8]],
+                &m[s[9]],
+            )?;
+            mixing_g(
+                cs.namespace(|| "mixing invocation 6"),
+                &mut v,
+                1,
+                6,
+                11,
+                12,
+                &m[s[10]],
+                &m[s[11]],
+            )?;
+            mixing_g(
+                cs.namespace(|| "mixing invocation 7"),
+                &mut v,
+                2,
+                7,
+                8,
+                13,
+                &m[s[12]],
+                &m[s[13]],
+            )?;
+            mixing_g(
+                cs.namespace(|| "mixing invocation 8"),
+                &mut v,
+                3,
+                4,
+                9,
+                14,
+                &m[s[14]],
+                &m[s[15]],
+            )?;
         }
     }
 
     for i in 0..8 {
-        let mut cs = cs.namespace(|| format!("h[{i}] ^ v[{i}] ^ v[{i} + 8]", i=i));
+        let mut cs = cs.namespace(|| format!("h[{i}] ^ v[{i}] ^ v[{i} + 8]", i = i));
 
         h[i] = h[i].xor(cs.namespace(|| "first xor"), &v[i])?;
         h[i] = h[i].xor(cs.namespace(|| "second xor"), &v[i + 8])?;
@@ -262,9 +342,8 @@ fn blake2s_compression<E: Engine, CS: ConstraintSystem<E>>(
 pub fn blake2s<E: Engine, CS: ConstraintSystem<E>>(
     mut cs: CS,
     input: &[Boolean],
-    personalization: &[u8]
+    personalization: &[u8],
-) -> Result<Vec<Boolean>, SynthesisError>
+) -> Result<Vec<Boolean>, SynthesisError> {
-{
     use byteorder::{ByteOrder, LittleEndian};
 
     assert_eq!(personalization.len(), 8);
@@ -279,8 +358,12 @@ pub fn blake2s<E: Engine, CS: ConstraintSystem<E>>(
     h.push(UInt32::constant(0x9B05688C));
 
     // Personalization is stored here
-    h.push(UInt32::constant(0x1F83D9AB ^ LittleEndian::read_u32(&personalization[0..4])));
+    h.push(UInt32::constant(
-    h.push(UInt32::constant(0x5BE0CD19 ^ LittleEndian::read_u32(&personalization[4..8])));
+        0x1F83D9AB ^ LittleEndian::read_u32(&personalization[0..4]),
+    ));
+    h.push(UInt32::constant(
+        0x5BE0CD19 ^ LittleEndian::read_u32(&personalization[4..8]),
+    ));
 
     let mut blocks: Vec<Vec<UInt32>> = vec![];
 
@@ -312,7 +395,13 @@ pub fn blake2s<E: Engine, CS: ConstraintSystem<E>>(
     {
         let cs = cs.namespace(|| "final block");
 
-        blake2s_compression(cs, &mut h, &blocks[blocks.len() - 1], (input.len() / 8) as u64, true)?;
+        blake2s_compression(
+            cs,
+            &mut h,
+            &blocks[blocks.len() - 1],
+            (input.len() / 8) as u64,
+            true,
+        )?;
     }
 
     Ok(h.iter().flat_map(|b| b.into_bits()).collect())
@@ -320,13 +409,15 @@ pub fn blake2s<E: Engine, CS: ConstraintSystem<E>>(
 
 #[cfg(test)]
 mod test {
-    use rand::{XorShiftRng, SeedableRng, Rng};
+    use blake2s_simd::Params as Blake2sParams;
-    use pairing::bls12_381::{Bls12};
+    use pairing::bls12_381::Bls12;
-    use ::circuit::boolean::{Boolean, AllocatedBit};
+    use rand_core::{RngCore, SeedableRng};
-    use ::circuit::test::TestConstraintSystem;
+    use rand_xorshift::XorShiftRng;
+
     use super::blake2s;
-    use bellman::{ConstraintSystem};
+    use crate::gadgets::boolean::{AllocatedBit, Boolean};
-    use blake2_rfc::blake2s::Blake2s;
+    use crate::gadgets::test::TestConstraintSystem;
+    use crate::ConstraintSystem;
 
     #[test]
     fn test_blank_hash() {
@@ -354,7 +445,13 @@ mod test {
     #[test]
     fn test_blake2s_constraints() {
         let mut cs = TestConstraintSystem::<Bls12>::new();
-        let input_bits: Vec<_> = (0..512).map(|i| AllocatedBit::alloc(cs.namespace(|| format!("input bit {}", i)), Some(true)).unwrap().into()).collect();
+        let input_bits: Vec<_> = (0..512)
+            .map(|i| {
+                AllocatedBit::alloc(cs.namespace(|| format!("input bit {}", i)), Some(true))
+                    .unwrap()
+                    .into()
+            })
+            .collect();
         blake2s(&mut cs, &input_bits, b"12345678").unwrap();
         assert!(cs.is_satisfied());
         assert_eq!(cs.num_constraints(), 21518);
@@ -366,12 +463,18 @@ mod test {
         // doesn't result in more constraints.
 
         let mut cs = TestConstraintSystem::<Bls12>::new();
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
         let input_bits: Vec<_> = (0..512)
-          .map(|_| Boolean::constant(rng.gen()))
+            .map(|_| Boolean::constant(rng.next_u32() % 2 != 0))
-          .chain((0..512)
+            .chain((0..512).map(|i| {
-                        .map(|i| AllocatedBit::alloc(cs.namespace(|| format!("input bit {}", i)), Some(true)).unwrap().into()))
+                AllocatedBit::alloc(cs.namespace(|| format!("input bit {}", i)), Some(true))
-          .collect();
+                    .unwrap()
+                    .into()
+            }))
+            .collect();
         blake2s(&mut cs, &input_bits, b"12345678").unwrap();
         assert!(cs.is_satisfied());
         assert_eq!(cs.num_constraints(), 21518);
@@ -380,21 +483,31 @@ mod test {
     #[test]
     fn test_blake2s_constant_constraints() {
         let mut cs = TestConstraintSystem::<Bls12>::new();
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
-        let input_bits: Vec<_> = (0..512).map(|_| Boolean::constant(rng.gen())).collect();
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
+        let input_bits: Vec<_> = (0..512)
+            .map(|_| Boolean::constant(rng.next_u32() % 2 != 0))
+            .collect();
         blake2s(&mut cs, &input_bits, b"12345678").unwrap();
         assert_eq!(cs.num_constraints(), 0);
     }
 
     #[test]
     fn test_blake2s() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
-        for input_len in (0..32).chain((32..256).filter(|a| a % 8 == 0))
+        for input_len in (0..32).chain((32..256).filter(|a| a % 8 == 0)) {
-        {
+            let mut h = Blake2sParams::new()
-            let mut h = Blake2s::with_params(32, &[], &[], b"12345678");
+                .hash_length(32)
+                .personal(b"12345678")
+                .to_state();
 
-            let data: Vec<u8> = (0..input_len).map(|_| rng.gen()).collect();
+            let data: Vec<u8> = (0..input_len).map(|_| rng.next_u32() as u8).collect();
 
             h.update(&data);
 
@@ -408,7 +521,11 @@ mod test {
                 for bit_i in 0..8 {
                     let cs = cs.namespace(|| format!("input bit {} {}", byte_i, bit_i));
 
-                    input_bits.push(AllocatedBit::alloc(cs, Some((input_byte >> bit_i) & 1u8 == 1u8)).unwrap().into());
+                    input_bits.push(
+                        AllocatedBit::alloc(cs, Some((input_byte >> bit_i) & 1u8 == 1u8))
+                            .unwrap()
+                            .into(),
+                    );
                 }
             }
 
@@ -416,17 +533,19 @@ mod test {
 
             assert!(cs.is_satisfied());
 
-            let mut s = hash_result.as_ref().iter()
+            let mut s = hash_result
-                                            .flat_map(|&byte| (0..8).map(move |i| (byte >> i) & 1u8 == 1u8));
+                .as_ref()
+                .iter()
+                .flat_map(|&byte| (0..8).map(move |i| (byte >> i) & 1u8 == 1u8));
 
             for b in r {
                 match b {
                     Boolean::Is(b) => {
                         assert!(s.next().unwrap() == b.get_value().unwrap());
-                    },
+                    }
                     Boolean::Not(b) => {
                         assert!(s.next().unwrap() != b.get_value().unwrap());
-                    },
+                    }
                     Boolean::Constant(b) => {
                         assert!(input_len == 0);
                         assert!(s.next().unwrap() == b);

bellman/src/gadgets/lookup.rs

@@ -1,21 +1,15 @@
-use pairing::{Engine, Field};
+use ff::Field;
-use super::*;
+use pairing::Engine;
-use super::num::{
+
-    AllocatedNum,
-    Num
-};
 use super::boolean::Boolean;
-use bellman::{
+use super::num::{AllocatedNum, Num};
-    ConstraintSystem
+use super::*;
-};
+use crate::ConstraintSystem;
 
 // Synthesize the constants for each base pattern.
-fn synth<'a, E: Engine, I>(
+fn synth<'a, E: Engine, I>(window_size: usize, constants: I, assignment: &mut [E::Fr])
-    window_size: usize,
+where
-    constants: I,
+    I: IntoIterator<Item = &'a E::Fr>,
-    assignment: &mut [E::Fr]
-)
-    where I: IntoIterator<Item=&'a E::Fr>
 {
     assert_eq!(assignment.len(), 1 << window_size);
 
@@ -37,16 +31,20 @@ fn synth<'a, E: Engine, I>(
 pub fn lookup3_xy<E: Engine, CS>(
     mut cs: CS,
     bits: &[Boolean],
-    coords: &[(E::Fr, E::Fr)]
+    coords: &[(E::Fr, E::Fr)],
 ) -> Result<(AllocatedNum<E>, AllocatedNum<E>), SynthesisError>
-    where CS: ConstraintSystem<E>
+where
+    CS: ConstraintSystem<E>,
 {
     assert_eq!(bits.len(), 3);
     assert_eq!(coords.len(), 8);
 
     // Calculate the index into `coords`
-    let i =
+    let i = match (
-    match (bits[0].get_value(), bits[1].get_value(), bits[2].get_value()) {
+        bits[0].get_value(),
+        bits[1].get_value(),
+        bits[2].get_value(),
+    ) {
         (Some(a_value), Some(b_value), Some(c_value)) => {
             let mut tmp = 0;
             if a_value {
@@ -59,25 +57,15 @@ pub fn lookup3_xy<E: Engine, CS>(
                 tmp += 4;
             }
             Some(tmp)
-        },
+        }
-        _ => None
+        _ => None,
     };
 
     // Allocate the x-coordinate resulting from the lookup
-    let res_x = AllocatedNum::alloc(
+    let res_x = AllocatedNum::alloc(cs.namespace(|| "x"), || Ok(coords[*i.get()?].0))?;
-        cs.namespace(|| "x"),
-        || {
-            Ok(coords[*i.get()?].0)
-        }
-    )?;
 
     // Allocate the y-coordinate resulting from the lookup
-    let res_y = AllocatedNum::alloc(
+    let res_y = AllocatedNum::alloc(cs.namespace(|| "y"), || Ok(coords[*i.get()?].1))?;
-        cs.namespace(|| "y"),
-        || {
-            Ok(coords[*i.get()?].1)
-        }
-    )?;
 
     // Compute the coefficients for the lookup constraints
     let mut x_coeffs = [E::Fr::zero(); 8];
@@ -91,30 +79,38 @@ pub fn lookup3_xy<E: Engine, CS>(
 
     cs.enforce(
         || "x-coordinate lookup",
-        |lc| lc + (x_coeffs[0b001], one)
+        |lc| {
+            lc + (x_coeffs[0b001], one)
                 + &bits[1].lc::<E>(one, x_coeffs[0b011])
                 + &bits[2].lc::<E>(one, x_coeffs[0b101])
-                + &precomp.lc::<E>(one, x_coeffs[0b111]),
+                + &precomp.lc::<E>(one, x_coeffs[0b111])
+        },
         |lc| lc + &bits[0].lc::<E>(one, E::Fr::one()),
-        |lc| lc + res_x.get_variable()
+        |lc| {
+            lc + res_x.get_variable()
                 - (x_coeffs[0b000], one)
                 - &bits[1].lc::<E>(one, x_coeffs[0b010])
                 - &bits[2].lc::<E>(one, x_coeffs[0b100])
-                - &precomp.lc::<E>(one, x_coeffs[0b110]),
+                - &precomp.lc::<E>(one, x_coeffs[0b110])
+        },
     );
 
     cs.enforce(
         || "y-coordinate lookup",
-        |lc| lc + (y_coeffs[0b001], one)
+        |lc| {
+            lc + (y_coeffs[0b001], one)
                 + &bits[1].lc::<E>(one, y_coeffs[0b011])
                 + &bits[2].lc::<E>(one, y_coeffs[0b101])
-                + &precomp.lc::<E>(one, y_coeffs[0b111]),
+                + &precomp.lc::<E>(one, y_coeffs[0b111])
+        },
         |lc| lc + &bits[0].lc::<E>(one, E::Fr::one()),
-        |lc| lc + res_y.get_variable()
+        |lc| {
+            lc + res_y.get_variable()
                 - (y_coeffs[0b000], one)
                 - &bits[1].lc::<E>(one, y_coeffs[0b010])
                 - &bits[2].lc::<E>(one, y_coeffs[0b100])
-                - &precomp.lc::<E>(one, y_coeffs[0b110]),
+                - &precomp.lc::<E>(one, y_coeffs[0b110])
+        },
     );
 
     Ok((res_x, res_y))
@@ -125,16 +121,16 @@ pub fn lookup3_xy<E: Engine, CS>(
 pub fn lookup3_xy_with_conditional_negation<E: Engine, CS>(
     mut cs: CS,
     bits: &[Boolean],
-    coords: &[(E::Fr, E::Fr)]
+    coords: &[(E::Fr, E::Fr)],
 ) -> Result<(Num<E>, Num<E>), SynthesisError>
-    where CS: ConstraintSystem<E>
+where
+    CS: ConstraintSystem<E>,
 {
     assert_eq!(bits.len(), 3);
     assert_eq!(coords.len(), 4);
 
     // Calculate the index into `coords`
-    let i =
+    let i = match (bits[0].get_value(), bits[1].get_value()) {
-    match (bits[0].get_value(), bits[1].get_value()) {
         (Some(a_value), Some(b_value)) => {
             let mut tmp = 0;
             if a_value {
@@ -144,22 +140,19 @@ pub fn lookup3_xy_with_conditional_negation<E: Engine, CS>(
                 tmp += 2;
             }
             Some(tmp)
-        },
+        }
-        _ => None
+        _ => None,
     };
 
     // Allocate the y-coordinate resulting from the lookup
     // and conditional negation
-    let y = AllocatedNum::alloc(
+    let y = AllocatedNum::alloc(cs.namespace(|| "y"), || {
-        cs.namespace(|| "y"),
+        let mut tmp = coords[*i.get()?].1;
-        || {
+        if *bits[2].get_value().get()? {
-            let mut tmp = coords[*i.get()?].1;
+            tmp.negate();
-            if *bits[2].get_value().get()? {
-                tmp.negate();
-            }
-            Ok(tmp)
         }
-    )?;
+        Ok(tmp)
+    })?;
 
     let one = CS::one();
 
@@ -172,21 +165,21 @@ pub fn lookup3_xy_with_conditional_negation<E: Engine, CS>(
     let precomp = Boolean::and(cs.namespace(|| "precomp"), &bits[0], &bits[1])?;
 
     let x = Num::zero()
-            .add_bool_with_coeff(one, &Boolean::constant(true), x_coeffs[0b00])
+        .add_bool_with_coeff(one, &Boolean::constant(true), x_coeffs[0b00])
-            .add_bool_with_coeff(one, &bits[0], x_coeffs[0b01])
+        .add_bool_with_coeff(one, &bits[0], x_coeffs[0b01])
-            .add_bool_with_coeff(one, &bits[1], x_coeffs[0b10])
+        .add_bool_with_coeff(one, &bits[1], x_coeffs[0b10])
-            .add_bool_with_coeff(one, &precomp, x_coeffs[0b11]);
+        .add_bool_with_coeff(one, &precomp, x_coeffs[0b11]);
 
-    let y_lc = precomp.lc::<E>(one, y_coeffs[0b11]) +
+    let y_lc = precomp.lc::<E>(one, y_coeffs[0b11])
-               &bits[1].lc::<E>(one, y_coeffs[0b10]) +
+        + &bits[1].lc::<E>(one, y_coeffs[0b10])
-               &bits[0].lc::<E>(one, y_coeffs[0b01]) +
+        + &bits[0].lc::<E>(one, y_coeffs[0b01])
-               (y_coeffs[0b00], one);
+        + (y_coeffs[0b00], one);
 
     cs.enforce(
         || "y-coordinate lookup",
         |lc| lc + &y_lc + &y_lc,
         |lc| lc + &bits[2].lc::<E>(one, E::Fr::one()),
-        |lc| lc + &y_lc - y.get_variable()
+        |lc| lc + &y_lc - y.get_variable(),
     );
 
     Ok((x, y.into()))
@@ -194,46 +187,52 @@ pub fn lookup3_xy_with_conditional_negation<E: Engine, CS>(
 
 #[cfg(test)]
 mod test {
-    use rand::{SeedableRng, Rand, Rng, XorShiftRng};
     use super::*;
-    use ::circuit::test::*;
+    use crate::gadgets::boolean::{AllocatedBit, Boolean};
-    use ::circuit::boolean::{Boolean, AllocatedBit};
+    use crate::gadgets::test::*;
     use pairing::bls12_381::{Bls12, Fr};
+    use rand_core::{RngCore, SeedableRng};
+    use rand_xorshift::XorShiftRng;
 
     #[test]
     fn test_lookup3_xy() {
-        let mut rng = XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0656]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..100 {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a_val = rng.gen();
+            let a_val = rng.next_u32() % 2 != 0;
-            let a = Boolean::from(
+            let a = Boolean::from(AllocatedBit::alloc(cs.namespace(|| "a"), Some(a_val)).unwrap());
-                AllocatedBit::alloc(cs.namespace(|| "a"), Some(a_val)).unwrap()
-            );
 
-            let b_val = rng.gen();
+            let b_val = rng.next_u32() % 2 != 0;
-            let b = Boolean::from(
+            let b = Boolean::from(AllocatedBit::alloc(cs.namespace(|| "b"), Some(b_val)).unwrap());
-                AllocatedBit::alloc(cs.namespace(|| "b"), Some(b_val)).unwrap()
-            );
 
-            let c_val = rng.gen();
+            let c_val = rng.next_u32() % 2 != 0;
-            let c = Boolean::from(
+            let c = Boolean::from(AllocatedBit::alloc(cs.namespace(|| "c"), Some(c_val)).unwrap());
-                AllocatedBit::alloc(cs.namespace(|| "c"), Some(c_val)).unwrap()
-            );
 
             let bits = vec![a, b, c];
 
-            let points: Vec<(Fr, Fr)> = (0..8).map(|_| (rng.gen(), rng.gen())).collect();
+            let points: Vec<(Fr, Fr)> = (0..8)
+                .map(|_| (Fr::random(&mut rng), Fr::random(&mut rng)))
+                .collect();
 
             let res = lookup3_xy(&mut cs, &bits, &points).unwrap();
 
             assert!(cs.is_satisfied());
 
             let mut index = 0;
-            if a_val { index += 1 }
+            if a_val {
-            if b_val { index += 2 }
+                index += 1
-            if c_val { index += 4 }
+            }
+            if b_val {
+                index += 2
+            }
+            if c_val {
+                index += 4
+            }
 
             assert_eq!(res.0.get_value().unwrap(), points[index].0);
             assert_eq!(res.1.get_value().unwrap(), points[index].1);
@@ -242,53 +241,63 @@ mod test {
 
     #[test]
     fn test_lookup3_xy_with_conditional_negation() {
-        let mut rng = XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..100 {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a_val = rng.gen();
+            let a_val = rng.next_u32() % 2 != 0;
-            let a = Boolean::from(
+            let a = Boolean::from(AllocatedBit::alloc(cs.namespace(|| "a"), Some(a_val)).unwrap());
-                AllocatedBit::alloc(cs.namespace(|| "a"), Some(a_val)).unwrap()
-            );
 
-            let b_val = rng.gen();
+            let b_val = rng.next_u32() % 2 != 0;
-            let b = Boolean::from(
+            let b = Boolean::from(AllocatedBit::alloc(cs.namespace(|| "b"), Some(b_val)).unwrap());
-                AllocatedBit::alloc(cs.namespace(|| "b"), Some(b_val)).unwrap()
-            );
 
-            let c_val = rng.gen();
+            let c_val = rng.next_u32() % 2 != 0;
-            let c = Boolean::from(
+            let c = Boolean::from(AllocatedBit::alloc(cs.namespace(|| "c"), Some(c_val)).unwrap());
-                AllocatedBit::alloc(cs.namespace(|| "c"), Some(c_val)).unwrap()
-            );
 
             let bits = vec![a, b, c];
 
-            let points: Vec<(Fr, Fr)> = (0..4).map(|_| (rng.gen(), rng.gen())).collect();
+            let points: Vec<(Fr, Fr)> = (0..4)
+                .map(|_| (Fr::random(&mut rng), Fr::random(&mut rng)))
+                .collect();
 
             let res = lookup3_xy_with_conditional_negation(&mut cs, &bits, &points).unwrap();
 
             assert!(cs.is_satisfied());
 
             let mut index = 0;
-            if a_val { index += 1 }
+            if a_val {
-            if b_val { index += 2 }
+                index += 1
+            }
+            if b_val {
+                index += 2
+            }
 
             assert_eq!(res.0.get_value().unwrap(), points[index].0);
             let mut tmp = points[index].1;
-            if c_val { tmp.negate() }
+            if c_val {
+                tmp.negate()
+            }
             assert_eq!(res.1.get_value().unwrap(), tmp);
         }
     }
 
     #[test]
     fn test_synth() {
-        let mut rng = XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         let window_size = 4;
 
         let mut assignment = vec![Fr::zero(); 1 << window_size];
-        let constants: Vec<_> = (0..(1 << window_size)).map(|_| Fr::rand(&mut rng)).collect();
+        let constants: Vec<_> = (0..(1 << window_size))
+            .map(|_| Fr::random(&mut rng))
+            .collect();
 
         synth::<Bls12, _>(window_size, &constants, &mut assignment);
 

bellman/src/gadgets/multieq.rs

@@ -1,17 +1,9 @@
-use pairing::{
+use ff::{Field, PrimeField};
-    Engine,
+use pairing::Engine;
-    Field,
-    PrimeField
-};
 
-use bellman::{
+use crate::{ConstraintSystem, LinearCombination, SynthesisError, Variable};
-    SynthesisError,
-    ConstraintSystem,
-    LinearCombination,
-    Variable
-};
 
-pub struct MultiEq<E: Engine, CS: ConstraintSystem<E>>{
+pub struct MultiEq<E: Engine, CS: ConstraintSystem<E>> {
     cs: CS,
     ops: usize,
     bits_used: usize,
@@ -26,12 +18,11 @@ impl<E: Engine, CS: ConstraintSystem<E>> MultiEq<E, CS> {
             ops: 0,
             bits_used: 0,
             lhs: LinearCombination::zero(),
-            rhs: LinearCombination::zero()
+            rhs: LinearCombination::zero(),
         }
     }
 
-    fn accumulate(&mut self)
+    fn accumulate(&mut self) {
-    {
         let ops = self.ops;
         let lhs = self.lhs.clone();
         let rhs = self.rhs.clone();
@@ -39,7 +30,7 @@ impl<E: Engine, CS: ConstraintSystem<E>> MultiEq<E, CS> {
             || format!("multieq {}", ops),
             |_| lhs,
             |lc| lc + CS::one(),
-            |_| rhs
+            |_| rhs,
         );
         self.lhs = LinearCombination::zero();
         self.rhs = LinearCombination::zero();
@@ -51,9 +42,8 @@ impl<E: Engine, CS: ConstraintSystem<E>> MultiEq<E, CS> {
         &mut self,
         num_bits: usize,
         lhs: &LinearCombination<E>,
-        rhs: &LinearCombination<E>
+        rhs: &LinearCombination<E>,
-    )
+    ) {
-    {
         // Check if we will exceed the capacity
         if (E::Fr::CAPACITY as usize) <= (self.bits_used + num_bits) {
             self.accumulate();
@@ -71,67 +61,60 @@ impl<E: Engine, CS: ConstraintSystem<E>> MultiEq<E, CS> {
 impl<E: Engine, CS: ConstraintSystem<E>> Drop for MultiEq<E, CS> {
     fn drop(&mut self) {
         if self.bits_used > 0 {
-           self.accumulate();
+            self.accumulate();
         }
     }
 }
 
-impl<E: Engine, CS: ConstraintSystem<E>> ConstraintSystem<E> for MultiEq<E, CS>
+impl<E: Engine, CS: ConstraintSystem<E>> ConstraintSystem<E> for MultiEq<E, CS> {
-{
     type Root = Self;
 
     fn one() -> Variable {
         CS::one()
     }
 
-    fn alloc<F, A, AR>(
+    fn alloc<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         self.cs.alloc(annotation, f)
     }
 
-    fn alloc_input<F, A, AR>(
+    fn alloc_input<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         self.cs.alloc_input(annotation, f)
     }
 
-    fn enforce<A, AR, LA, LB, LC>(
+    fn enforce<A, AR, LA, LB, LC>(&mut self, annotation: A, a: LA, b: LB, c: LC)
-        &mut self,
+    where
-        annotation: A,
+        A: FnOnce() -> AR,
-        a: LA,
+        AR: Into<String>,
-        b: LB,
+        LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        c: LC
+        LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-    )
+        LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        where A: FnOnce() -> AR, AR: Into<String>,
-              LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>
     {
         self.cs.enforce(annotation, a, b, c)
     }
 
     fn push_namespace<NR, N>(&mut self, name_fn: N)
-        where NR: Into<String>, N: FnOnce() -> NR
+    where
+        NR: Into<String>,
+        N: FnOnce() -> NR,
     {
         self.cs.get_root().push_namespace(name_fn)
     }
 
-    fn pop_namespace(&mut self)
+    fn pop_namespace(&mut self) {
-    {
         self.cs.get_root().pop_namespace()
     }
 
-    fn get_root(&mut self) -> &mut Self::Root
+    fn get_root(&mut self) -> &mut Self::Root {
-    {
         self
     }
 }

bellman/src/gadgets/multipack.rs

@@ -0,0 +1,110 @@
+use super::boolean::Boolean;
+use super::num::Num;
+use super::Assignment;
+use crate::{ConstraintSystem, SynthesisError};
+use ff::{Field, PrimeField};
+use pairing::Engine;
+
+/// Takes a sequence of booleans and exposes them as compact
+/// public inputs
+pub fn pack_into_inputs<E, CS>(mut cs: CS, bits: &[Boolean]) -> Result<(), SynthesisError>
+where
+    E: Engine,
+    CS: ConstraintSystem<E>,
+{
+    for (i, bits) in bits.chunks(E::Fr::CAPACITY as usize).enumerate() {
+        let mut num = Num::<E>::zero();
+        let mut coeff = E::Fr::one();
+        for bit in bits {
+            num = num.add_bool_with_coeff(CS::one(), bit, coeff);
+
+            coeff.double();
+        }
+
+        let input = cs.alloc_input(|| format!("input {}", i), || Ok(*num.get_value().get()?))?;
+
+        // num * 1 = input
+        cs.enforce(
+            || format!("packing constraint {}", i),
+            |_| num.lc(E::Fr::one()),
+            |lc| lc + CS::one(),
+            |lc| lc + input,
+        );
+    }
+
+    Ok(())
+}
+
+pub fn bytes_to_bits(bytes: &[u8]) -> Vec<bool> {
+    bytes
+        .iter()
+        .flat_map(|&v| (0..8).rev().map(move |i| (v >> i) & 1 == 1))
+        .collect()
+}
+
+pub fn bytes_to_bits_le(bytes: &[u8]) -> Vec<bool> {
+    bytes
+        .iter()
+        .flat_map(|&v| (0..8).map(move |i| (v >> i) & 1 == 1))
+        .collect()
+}
+
+pub fn compute_multipacking<E: Engine>(bits: &[bool]) -> Vec<E::Fr> {
+    let mut result = vec![];
+
+    for bits in bits.chunks(E::Fr::CAPACITY as usize) {
+        let mut cur = E::Fr::zero();
+        let mut coeff = E::Fr::one();
+
+        for bit in bits {
+            if *bit {
+                cur.add_assign(&coeff);
+            }
+
+            coeff.double();
+        }
+
+        result.push(cur);
+    }
+
+    result
+}
+
+#[test]
+fn test_multipacking() {
+    use crate::ConstraintSystem;
+    use pairing::bls12_381::Bls12;
+    use rand_core::{RngCore, SeedableRng};
+    use rand_xorshift::XorShiftRng;
+
+    use super::boolean::{AllocatedBit, Boolean};
+    use crate::gadgets::test::*;
+
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
+
+    for num_bits in 0..1500 {
+        let mut cs = TestConstraintSystem::<Bls12>::new();
+
+        let bits: Vec<bool> = (0..num_bits).map(|_| rng.next_u32() % 2 != 0).collect();
+
+        let circuit_bits = bits
+            .iter()
+            .enumerate()
+            .map(|(i, &b)| {
+                Boolean::from(
+                    AllocatedBit::alloc(cs.namespace(|| format!("bit {}", i)), Some(b)).unwrap(),
+                )
+            })
+            .collect::<Vec<_>>();
+
+        let expected_inputs = compute_multipacking::<Bls12>(&bits);
+
+        pack_into_inputs(cs.namespace(|| "pack"), &circuit_bits).unwrap();
+
+        assert!(cs.is_satisfied());
+        assert!(cs.verify(&expected_inputs));
+    }
+}

bellman/src/gadgets/num.rs

@@ -1,83 +1,61 @@
-use pairing::{
+use ff::{BitIterator, Field, PrimeField, PrimeFieldRepr};
-    Engine,
+use pairing::Engine;
-    Field,
-    PrimeField,
-    PrimeFieldRepr,
-    BitIterator
-};
 
-use bellman::{
+use crate::{ConstraintSystem, LinearCombination, SynthesisError, Variable};
-    SynthesisError,
-    ConstraintSystem,
-    LinearCombination,
-    Variable
-};
 
-use super::{
+use super::Assignment;
-    Assignment
-};
 
-use super::boolean::{
+use super::boolean::{self, AllocatedBit, Boolean};
-    self,
-    Boolean,
-    AllocatedBit
-};
 
 pub struct AllocatedNum<E: Engine> {
     value: Option<E::Fr>,
-    variable: Variable
+    variable: Variable,
 }
 
 impl<E: Engine> Clone for AllocatedNum<E> {
     fn clone(&self) -> Self {
         AllocatedNum {
             value: self.value,
-            variable: self.variable
+            variable: self.variable,
         }
     }
 }
 
 impl<E: Engine> AllocatedNum<E> {
-    pub fn alloc<CS, F>(
+    pub fn alloc<CS, F>(mut cs: CS, value: F) -> Result<Self, SynthesisError>
-        mut cs: CS,
+    where
-        value: F,
+        CS: ConstraintSystem<E>,
-    ) -> Result<Self, SynthesisError>
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        where CS: ConstraintSystem<E>,
-              F: FnOnce() -> Result<E::Fr, SynthesisError>
     {
         let mut new_value = None;
-        let var = cs.alloc(|| "num", || {
+        let var = cs.alloc(
-            let tmp = value()?;
+            || "num",
+            || {
+                let tmp = value()?;
 
-            new_value = Some(tmp);
+                new_value = Some(tmp);
 
-            Ok(tmp)
+                Ok(tmp)
-        })?;
+            },
+        )?;
 
         Ok(AllocatedNum {
             value: new_value,
-            variable: var
+            variable: var,
         })
     }
 
-    pub fn inputize<CS>(
+    pub fn inputize<CS>(&self, mut cs: CS) -> Result<(), SynthesisError>
-        &self,
+    where
-        mut cs: CS
+        CS: ConstraintSystem<E>,
-    ) -> Result<(), SynthesisError>
-        where CS: ConstraintSystem<E>
     {
-        let input = cs.alloc_input(
+        let input = cs.alloc_input(|| "input variable", || Ok(*self.value.get()?))?;
-            || "input variable",
-            || {
-                Ok(*self.value.get()?)
-            }
-        )?;
 
         cs.enforce(
             || "enforce input is correct",
             |lc| lc + input,
             |lc| lc + CS::one(),
-            |lc| lc + self.variable
+            |lc| lc + self.variable,
         );
 
         Ok(())
@@ -88,18 +66,17 @@ impl<E: Engine> AllocatedNum<E> {
     /// order, requiring that the representation
     /// strictly exists "in the field" (i.e., a
     /// congruency is not allowed.)
-    pub fn into_bits_le_strict<CS>(
+    pub fn into_bits_le_strict<CS>(&self, mut cs: CS) -> Result<Vec<Boolean>, SynthesisError>
-        &self,
+    where
-        mut cs: CS
+        CS: ConstraintSystem<E>,
-    ) -> Result<Vec<Boolean>, SynthesisError>
-        where CS: ConstraintSystem<E>
     {
         pub fn kary_and<E, CS>(
             mut cs: CS,
-            v: &[AllocatedBit]
+            v: &[AllocatedBit],
         ) -> Result<AllocatedBit, SynthesisError>
-            where E: Engine,
+        where
-                  CS: ConstraintSystem<E>
+            E: Engine,
+            CS: ConstraintSystem<E>,
         {
             assert!(v.len() > 0);
 
@@ -114,7 +91,7 @@ impl<E: Engine> AllocatedNum<E> {
                     cur = Some(AllocatedBit::and(
                         cs.namespace(|| format!("and {}", i)),
                         cur.as_ref().unwrap(),
-                        v
+                        v,
                     )?);
                 }
             }
@@ -150,10 +127,7 @@ impl<E: Engine> AllocatedNum<E> {
             if b {
                 // This is part of a run of ones. Let's just
                 // allocate the boolean with the expected value.
-                let a_bit = AllocatedBit::alloc(
+                let a_bit = AllocatedBit::alloc(cs.namespace(|| format!("bit {}", i)), a_bit)?;
-                    cs.namespace(|| format!("bit {}", i)),
-                    a_bit
-                )?;
                 // ... and add it to the current run of ones.
                 current_run.push(a_bit.clone());
                 result.push(a_bit);
@@ -167,7 +141,7 @@ impl<E: Engine> AllocatedNum<E> {
                     }
                     last_run = Some(kary_and(
                         cs.namespace(|| format!("run ending at {}", i)),
-                        &current_run
+                        &current_run,
                     )?);
                     current_run.truncate(0);
                 }
@@ -180,7 +154,7 @@ impl<E: Engine> AllocatedNum<E> {
                 let a_bit = AllocatedBit::alloc_conditionally(
                     cs.namespace(|| format!("bit {}", i)),
                     a_bit,
-                    &last_run.as_ref().expect("char always starts with a one")
+                    &last_run.as_ref().expect("char always starts with a one"),
                 )?;
                 result.push(a_bit);
             }
@@ -206,12 +180,7 @@ impl<E: Engine> AllocatedNum<E> {
 
         lc = lc - self.variable;
 
-        cs.enforce(
+        cs.enforce(|| "unpacking constraint", |lc| lc, |lc| lc, |_| lc);
-            || "unpacking constraint",
-            |lc| lc,
-            |lc| lc,
-            |_| lc
-        );
 
         // Convert into booleans, and reverse for little-endian bit order
         Ok(result.into_iter().map(|b| Boolean::from(b)).rev().collect())
@@ -220,16 +189,11 @@ impl<E: Engine> AllocatedNum<E> {
     /// Convert the allocated number into its little-endian representation.
     /// Note that this does not strongly enforce that the commitment is
     /// "in the field."
-    pub fn into_bits_le<CS>(
+    pub fn into_bits_le<CS>(&self, mut cs: CS) -> Result<Vec<Boolean>, SynthesisError>
-        &self,
+    where
-        mut cs: CS
+        CS: ConstraintSystem<E>,
-    ) -> Result<Vec<Boolean>, SynthesisError>
-        where CS: ConstraintSystem<E>
     {
-        let bits = boolean::field_into_allocated_bits_le(
+        let bits = boolean::field_into_allocated_bits_le(&mut cs, self.value)?;
-            &mut cs,
-            self.value
-        )?;
 
         let mut lc = LinearCombination::zero();
         let mut coeff = E::Fr::one();
@@ -242,94 +206,91 @@ impl<E: Engine> AllocatedNum<E> {
 
         lc = lc - self.variable;
 
-        cs.enforce(
+        cs.enforce(|| "unpacking constraint", |lc| lc, |lc| lc, |_| lc);
-            || "unpacking constraint",
-            |lc| lc,
-            |lc| lc,
-            |_| lc
-        );
 
         Ok(bits.into_iter().map(|b| Boolean::from(b)).collect())
     }
 
-    pub fn mul<CS>(
+    pub fn mul<CS>(&self, mut cs: CS, other: &Self) -> Result<Self, SynthesisError>
-        &self,
+    where
-        mut cs: CS,
+        CS: ConstraintSystem<E>,
-        other: &Self
-    ) -> Result<Self, SynthesisError>
-        where CS: ConstraintSystem<E>
     {
         let mut value = None;
 
-        let var = cs.alloc(|| "product num", || {
+        let var = cs.alloc(
-            let mut tmp = *self.value.get()?;
+            || "product num",
-            tmp.mul_assign(other.value.get()?);
+            || {
+                let mut tmp = *self.value.get()?;
+                tmp.mul_assign(other.value.get()?);
 
-            value = Some(tmp);
+                value = Some(tmp);
 
-            Ok(tmp)
+                Ok(tmp)
-        })?;
+            },
+        )?;
 
         // Constrain: a * b = ab
         cs.enforce(
             || "multiplication constraint",
             |lc| lc + self.variable,
             |lc| lc + other.variable,
-            |lc| lc + var
+            |lc| lc + var,
         );
 
         Ok(AllocatedNum {
             value: value,
-            variable: var
+            variable: var,
         })
     }
 
-    pub fn square<CS>(
+    pub fn square<CS>(&self, mut cs: CS) -> Result<Self, SynthesisError>
-        &self,
+    where
-        mut cs: CS
+        CS: ConstraintSystem<E>,
-    ) -> Result<Self, SynthesisError>
-        where CS: ConstraintSystem<E>
     {
         let mut value = None;
 
-        let var = cs.alloc(|| "squared num", || {
+        let var = cs.alloc(
-            let mut tmp = *self.value.get()?;
+            || "squared num",
-            tmp.square();
+            || {
+                let mut tmp = *self.value.get()?;
+                tmp.square();
 
-            value = Some(tmp);
+                value = Some(tmp);
 
-            Ok(tmp)
+                Ok(tmp)
-        })?;
+            },
+        )?;
 
         // Constrain: a * a = aa
         cs.enforce(
             || "squaring constraint",
             |lc| lc + self.variable,
             |lc| lc + self.variable,
-            |lc| lc + var
+            |lc| lc + var,
         );
 
         Ok(AllocatedNum {
             value: value,
-            variable: var
+            variable: var,
         })
     }
 
-    pub fn assert_nonzero<CS>(
+    pub fn assert_nonzero<CS>(&self, mut cs: CS) -> Result<(), SynthesisError>
-        &self,
+    where
-        mut cs: CS
+        CS: ConstraintSystem<E>,
-    ) -> Result<(), SynthesisError>
-        where CS: ConstraintSystem<E>
     {
-        let inv = cs.alloc(|| "ephemeral inverse", || {
+        let inv = cs.alloc(
-            let tmp = *self.value.get()?;
+            || "ephemeral inverse",
-            
+            || {
-            if tmp.is_zero() {
+                let tmp = *self.value.get()?;
-                Err(SynthesisError::DivisionByZero)
+
-            } else {
+                if tmp.is_zero() {
-                Ok(tmp.inverse().unwrap())
+                    Err(SynthesisError::DivisionByZero)
-            }
+                } else {
-        })?;
+                    Ok(tmp.inverse().unwrap())
+                }
+            },
+        )?;
 
         // Constrain a * inv = 1, which is only valid
         // iff a has a multiplicative inverse, untrue
@@ -338,7 +299,7 @@ impl<E: Engine> AllocatedNum<E> {
             || "nonzero assertion constraint",
             |lc| lc + self.variable,
             |lc| lc + inv,
-            |lc| lc + CS::one()
+            |lc| lc + CS::one(),
         );
 
         Ok(())
@@ -351,44 +312,39 @@ impl<E: Engine> AllocatedNum<E> {
         mut cs: CS,
         a: &Self,
         b: &Self,
-        condition: &Boolean
+        condition: &Boolean,
     ) -> Result<(Self, Self), SynthesisError>
-        where CS: ConstraintSystem<E>
+    where
+        CS: ConstraintSystem<E>,
     {
-        let c = Self::alloc(
+        let c = Self::alloc(cs.namespace(|| "conditional reversal result 1"), || {
-            cs.namespace(|| "conditional reversal result 1"),
+            if *condition.get_value().get()? {
-            || {
+                Ok(*b.value.get()?)
-                if *condition.get_value().get()? {
+            } else {
-                    Ok(*b.value.get()?)
+                Ok(*a.value.get()?)
-                } else {
-                    Ok(*a.value.get()?)
-                }
             }
-        )?;
+        })?;
 
         cs.enforce(
             || "first conditional reversal",
             |lc| lc + a.variable - b.variable,
             |_| condition.lc(CS::one(), E::Fr::one()),
-            |lc| lc + a.variable - c.variable
+            |lc| lc + a.variable - c.variable,
         );
 
-        let d = Self::alloc(
+        let d = Self::alloc(cs.namespace(|| "conditional reversal result 2"), || {
-            cs.namespace(|| "conditional reversal result 2"),
+            if *condition.get_value().get()? {
-            || {
+                Ok(*a.value.get()?)
-                if *condition.get_value().get()? {
+            } else {
-                    Ok(*a.value.get()?)
+                Ok(*b.value.get()?)
-                } else {
-                    Ok(*b.value.get()?)
-                }
             }
-        )?;
+        })?;
 
         cs.enforce(
             || "second conditional reversal",
             |lc| lc + b.variable - a.variable,
             |_| condition.lc(CS::one(), E::Fr::one()),
-            |lc| lc + b.variable - d.variable
+            |lc| lc + b.variable - d.variable,
         );
 
         Ok((c, d))
@@ -405,14 +361,14 @@ impl<E: Engine> AllocatedNum<E> {
 
 pub struct Num<E: Engine> {
     value: Option<E::Fr>,
-    lc: LinearCombination<E>
+    lc: LinearCombination<E>,
 }
 
 impl<E: Engine> From<AllocatedNum<E>> for Num<E> {
     fn from(num: AllocatedNum<E>) -> Num<E> {
         Num {
             value: num.value,
-            lc: LinearCombination::<E>::zero() + num.variable
+            lc: LinearCombination::<E>::zero() + num.variable,
         }
     }
 }
@@ -421,7 +377,7 @@ impl<E: Engine> Num<E> {
     pub fn zero() -> Self {
         Num {
             value: Some(E::Fr::zero()),
-            lc: LinearCombination::zero()
+            lc: LinearCombination::zero(),
         }
     }
 
@@ -433,13 +389,7 @@ impl<E: Engine> Num<E> {
         LinearCombination::zero() + (coeff, &self.lc)
     }
 
-    pub fn add_bool_with_coeff(
+    pub fn add_bool_with_coeff(self, one: Variable, bit: &Boolean, coeff: E::Fr) -> Self {
-        self,
-        one: Variable,
-        bit: &Boolean,
-        coeff: E::Fr
-    ) -> Self
-    {
         let newval = match (self.value, bit.get_value()) {
             (Some(mut curval), Some(bval)) => {
                 if bval {
@@ -447,25 +397,27 @@ impl<E: Engine> Num<E> {
                 }
 
                 Some(curval)
-            },
+            }
-            _ => None
+            _ => None,
         };
 
         Num {
             value: newval,
-            lc: self.lc + &bit.lc(one, coeff)
+            lc: self.lc + &bit.lc(one, coeff),
         }
     }
 }
 
 #[cfg(test)]
 mod test {
-    use rand::{SeedableRng, Rand, Rng, XorShiftRng};
+    use crate::ConstraintSystem;
-    use bellman::{ConstraintSystem};
+    use ff::{BitIterator, Field, PrimeField};
     use pairing::bls12_381::{Bls12, Fr};
-    use pairing::{Field, PrimeField, BitIterator};
+    use rand_core::SeedableRng;
-    use ::circuit::test::*;
+    use rand_xorshift::XorShiftRng;
+
     use super::{AllocatedNum, Boolean};
+    use crate::gadgets::test::*;
 
     #[test]
     fn test_allocated_num() {
@@ -494,8 +446,10 @@ mod test {
     fn test_num_multiplication() {
         let mut cs = TestConstraintSystem::<Bls12>::new();
 
-        let n = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::from_str("12").unwrap())).unwrap();
+        let n =
-        let n2 = AllocatedNum::alloc(cs.namespace(|| "b"), || Ok(Fr::from_str("10").unwrap())).unwrap();
+            AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::from_str("12").unwrap())).unwrap();
+        let n2 =
+            AllocatedNum::alloc(cs.namespace(|| "b"), || Ok(Fr::from_str("10").unwrap())).unwrap();
         let n3 = n.mul(&mut cs, &n2).unwrap();
 
         assert!(cs.is_satisfied());
@@ -507,12 +461,15 @@ mod test {
 
     #[test]
     fn test_num_conditional_reversal() {
-        let mut rng = XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
         {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(rng.gen())).unwrap();
+            let a = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::random(&mut rng))).unwrap();
-            let b = AllocatedNum::alloc(cs.namespace(|| "b"), || Ok(rng.gen())).unwrap();
+            let b = AllocatedNum::alloc(cs.namespace(|| "b"), || Ok(Fr::random(&mut rng))).unwrap();
             let condition = Boolean::constant(false);
             let (c, d) = AllocatedNum::conditionally_reverse(&mut cs, &a, &b, &condition).unwrap();
 
@@ -525,8 +482,8 @@ mod test {
         {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(rng.gen())).unwrap();
+            let a = AllocatedNum::alloc(cs.namespace(|| "a"), || Ok(Fr::random(&mut rng))).unwrap();
-            let b = AllocatedNum::alloc(cs.namespace(|| "b"), || Ok(rng.gen())).unwrap();
+            let b = AllocatedNum::alloc(cs.namespace(|| "b"), || Ok(Fr::random(&mut rng))).unwrap();
             let condition = Boolean::constant(true);
             let (c, d) = AllocatedNum::conditionally_reverse(&mut cs, &a, &b, &condition).unwrap();
 
@@ -573,15 +530,21 @@ mod test {
         cs.set("bit 254/boolean", Fr::one());
 
         // this makes the conditional boolean constraint fail
-        assert_eq!(cs.which_is_unsatisfied().unwrap(), "bit 254/boolean constraint");
+        assert_eq!(
+            cs.which_is_unsatisfied().unwrap(),
+            "bit 254/boolean constraint"
+        );
     }
 
     #[test]
     fn test_into_bits() {
-        let mut rng = XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for i in 0..200 {
-            let r = Fr::rand(&mut rng);
+            let r = Fr::random(&mut rng);
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
             let n = AllocatedNum::alloc(&mut cs, || Ok(r)).unwrap();
@@ -594,7 +557,10 @@ mod test {
 
             assert!(cs.is_satisfied());
 
-            for (b, a) in BitIterator::new(r.into_repr()).skip(1).zip(bits.iter().rev()) {
+            for (b, a) in BitIterator::new(r.into_repr())
+                .skip(1)
+                .zip(bits.iter().rev())
+            {
                 if let &Boolean::Is(ref a) = a {
                     assert_eq!(b, a.get_value().unwrap());
                 } else {
@@ -602,7 +568,7 @@ mod test {
                 }
             }
 
-            cs.set("num", Fr::rand(&mut rng));
+            cs.set("num", Fr::random(&mut rng));
             assert!(!cs.is_satisfied());
             cs.set("num", r);
             assert!(cs.is_satisfied());

bellman/src/gadgets/sha256.rs

@@ -1,7 +1,7 @@
-use super::uint32::UInt32;
-use super::multieq::MultiEq;
 use super::boolean::Boolean;
-use bellman::{ConstraintSystem, SynthesisError};
+use super::multieq::MultiEq;
+use super::uint32::UInt32;
+use crate::{ConstraintSystem, SynthesisError};
 use pairing::Engine;
 
 const ROUND_CONSTANTS: [u32; 64] = [
@@ -12,37 +12,35 @@ const ROUND_CONSTANTS: [u32; 64] = [
     0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
     0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
     0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
-    0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
+    0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2,
 ];
 
 const IV: [u32; 8] = [
-    0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
+    0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19,
-    0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19
 ];
 
 pub fn sha256_block_no_padding<E, CS>(
     mut cs: CS,
-    input: &[Boolean]
+    input: &[Boolean],
 ) -> Result<Vec<Boolean>, SynthesisError>
-    where E: Engine, CS: ConstraintSystem<E>
+where
+    E: Engine,
+    CS: ConstraintSystem<E>,
 {
     assert_eq!(input.len(), 512);
 
-    Ok(sha256_compression_function(
+    Ok(
-        &mut cs,
+        sha256_compression_function(&mut cs, &input, &get_sha256_iv())?
-        &input,
+            .into_iter()
-        &get_sha256_iv()
+            .flat_map(|e| e.into_bits_be())
-    )?
+            .collect(),
-    .into_iter()
+    )
-    .flat_map(|e| e.into_bits_be())
-    .collect())
 }
 
-pub fn sha256<E, CS>(
+pub fn sha256<E, CS>(mut cs: CS, input: &[Boolean]) -> Result<Vec<Boolean>, SynthesisError>
-    mut cs: CS,
+where
-    input: &[Boolean]
+    E: Engine,
-) -> Result<Vec<Boolean>, SynthesisError>
+    CS: ConstraintSystem<E>,
-    where E: Engine, CS: ConstraintSystem<E>
 {
     assert!(input.len() % 8 == 0);
 
@@ -62,16 +60,10 @@ pub fn sha256<E, CS>(
 
     let mut cur = get_sha256_iv();
     for (i, block) in padded.chunks(512).enumerate() {
-        cur = sha256_compression_function(
+        cur = sha256_compression_function(cs.namespace(|| format!("block {}", i)), block, &cur)?;
-            cs.namespace(|| format!("block {}", i)),
-            block,
-            &cur
-        )?;
     }
 
-    Ok(cur.into_iter()
+    Ok(cur.into_iter().flat_map(|e| e.into_bits_be()).collect())
-    .flat_map(|e| e.into_bits_be())
-    .collect())
 }
 
 fn get_sha256_iv() -> Vec<UInt32> {
@@ -81,16 +73,19 @@ fn get_sha256_iv() -> Vec<UInt32> {
 fn sha256_compression_function<E, CS>(
     cs: CS,
     input: &[Boolean],
-    current_hash_value: &[UInt32]
+    current_hash_value: &[UInt32],
 ) -> Result<Vec<UInt32>, SynthesisError>
-    where E: Engine, CS: ConstraintSystem<E>
+where
+    E: Engine,
+    CS: ConstraintSystem<E>,
 {
     assert_eq!(input.len(), 512);
     assert_eq!(current_hash_value.len(), 8);
 
-    let mut w = input.chunks(32)
+    let mut w = input
-                     .map(|e| UInt32::from_bits_be(e))
+        .chunks(32)
-                     .collect::<Vec<_>>();
+        .map(|e| UInt32::from_bits_be(e))
+        .collect::<Vec<_>>();
 
     // We can save some constraints by combining some of
     // the constraints in different u32 additions
@@ -100,30 +95,18 @@ fn sha256_compression_function<E, CS>(
         let cs = &mut cs.namespace(|| format!("w extension {}", i));
 
         // s0 := (w[i-15] rightrotate 7) xor (w[i-15] rightrotate 18) xor (w[i-15] rightshift 3)
-        let mut s0 = w[i-15].rotr(7);
+        let mut s0 = w[i - 15].rotr(7);
-        s0 = s0.xor(
+        s0 = s0.xor(cs.namespace(|| "first xor for s0"), &w[i - 15].rotr(18))?;
-            cs.namespace(|| "first xor for s0"),
+        s0 = s0.xor(cs.namespace(|| "second xor for s0"), &w[i - 15].shr(3))?;
-            &w[i-15].rotr(18)
-        )?;
-        s0 = s0.xor(
-            cs.namespace(|| "second xor for s0"),
-            &w[i-15].shr(3)
-        )?;
 
         // s1 := (w[i-2] rightrotate 17) xor (w[i-2] rightrotate 19) xor (w[i-2] rightshift 10)
-        let mut s1 = w[i-2].rotr(17);
+        let mut s1 = w[i - 2].rotr(17);
-        s1 = s1.xor(
+        s1 = s1.xor(cs.namespace(|| "first xor for s1"), &w[i - 2].rotr(19))?;
-            cs.namespace(|| "first xor for s1"),
+        s1 = s1.xor(cs.namespace(|| "second xor for s1"), &w[i - 2].shr(10))?;
-            &w[i-2].rotr(19)
-        )?;
-        s1 = s1.xor(
-            cs.namespace(|| "second xor for s1"),
-            &w[i-2].shr(10)
-        )?;
 
         let tmp = UInt32::addmany(
             cs.namespace(|| "computation of w[i]"),
-            &[w[i-16].clone(), s0, w[i-7].clone(), s1]
+            &[w[i - 16].clone(), s0, w[i - 7].clone(), s1],
         )?;
 
         // w[i] := w[i-16] + s0 + w[i-7] + s1
@@ -134,29 +117,21 @@ fn sha256_compression_function<E, CS>(
 
     enum Maybe {
         Deferred(Vec<UInt32>),
-        Concrete(UInt32)
+        Concrete(UInt32),
     }
 
     impl Maybe {
-        fn compute<E, CS, M>(
+        fn compute<E, CS, M>(self, cs: M, others: &[UInt32]) -> Result<UInt32, SynthesisError>
-            self,
+        where
-            cs: M,
+            E: Engine,
-            others: &[UInt32]
+            CS: ConstraintSystem<E>,
-        ) -> Result<UInt32, SynthesisError>
+            M: ConstraintSystem<E, Root = MultiEq<E, CS>>,
-            where E: Engine,
-                  CS: ConstraintSystem<E>,
-                  M: ConstraintSystem<E, Root=MultiEq<E, CS>>
         {
             Ok(match self {
-                Maybe::Concrete(ref v) => {
+                Maybe::Concrete(ref v) => return Ok(v.clone()),
-                    return Ok(v.clone())
-                },
                 Maybe::Deferred(mut v) => {
                     v.extend(others.into_iter().cloned());
-                    UInt32::addmany(
+                    UInt32::addmany(cs, &v)?
-                        cs,
-                        &v
-                    )?
                 }
             })
         }
@@ -177,22 +152,11 @@ fn sha256_compression_function<E, CS>(
         // S1 := (e rightrotate 6) xor (e rightrotate 11) xor (e rightrotate 25)
         let new_e = e.compute(cs.namespace(|| "deferred e computation"), &[])?;
         let mut s1 = new_e.rotr(6);
-        s1 = s1.xor(
+        s1 = s1.xor(cs.namespace(|| "first xor for s1"), &new_e.rotr(11))?;
-            cs.namespace(|| "first xor for s1"),
+        s1 = s1.xor(cs.namespace(|| "second xor for s1"), &new_e.rotr(25))?;
-            &new_e.rotr(11)
-        )?;
-        s1 = s1.xor(
-            cs.namespace(|| "second xor for s1"),
-            &new_e.rotr(25)
-        )?;
 
         // ch := (e and f) xor ((not e) and g)
-        let ch = UInt32::sha256_ch(
+        let ch = UInt32::sha256_ch(cs.namespace(|| "ch"), &new_e, &f, &g)?;
-            cs.namespace(|| "ch"),
-            &new_e,
-            &f,
-            &g
-        )?;
 
         // temp1 := h + S1 + ch + k[i] + w[i]
         let temp1 = vec![
@@ -200,28 +164,17 @@ fn sha256_compression_function<E, CS>(
             s1,
             ch,
             UInt32::constant(ROUND_CONSTANTS[i]),
-            w[i].clone()
+            w[i].clone(),
         ];
 
         // S0 := (a rightrotate 2) xor (a rightrotate 13) xor (a rightrotate 22)
         let new_a = a.compute(cs.namespace(|| "deferred a computation"), &[])?;
         let mut s0 = new_a.rotr(2);
-        s0 = s0.xor(
+        s0 = s0.xor(cs.namespace(|| "first xor for s0"), &new_a.rotr(13))?;
-            cs.namespace(|| "first xor for s0"),
+        s0 = s0.xor(cs.namespace(|| "second xor for s0"), &new_a.rotr(22))?;
-            &new_a.rotr(13)
-        )?;
-        s0 = s0.xor(
-            cs.namespace(|| "second xor for s0"),
-            &new_a.rotr(22)
-        )?;
 
         // maj := (a and b) xor (a and c) xor (b and c)
-        let maj = UInt32::sha256_maj(
+        let maj = UInt32::sha256_maj(cs.namespace(|| "maj"), &new_a, &b, &c)?;
-            cs.namespace(|| "maj"),
-            &new_a,
-            &b,
-            &c
-        )?;
 
         // temp2 := S0 + maj
         let temp2 = vec![s0, maj];
@@ -244,7 +197,13 @@ fn sha256_compression_function<E, CS>(
         d = c;
         c = b;
         b = new_a;
-        a = Maybe::Deferred(temp1.iter().cloned().chain(temp2.iter().cloned()).collect::<Vec<_>>());
+        a = Maybe::Deferred(
+            temp1
+                .iter()
+                .cloned()
+                .chain(temp2.iter().cloned())
+                .collect::<Vec<_>>(),
+        );
     }
 
     /*
@@ -261,42 +220,42 @@ fn sha256_compression_function<E, CS>(
 
     let h0 = a.compute(
         cs.namespace(|| "deferred h0 computation"),
-        &[current_hash_value[0].clone()]
+        &[current_hash_value[0].clone()],
     )?;
 
     let h1 = UInt32::addmany(
         cs.namespace(|| "new h1"),
-        &[current_hash_value[1].clone(), b]
+        &[current_hash_value[1].clone(), b],
     )?;
 
     let h2 = UInt32::addmany(
         cs.namespace(|| "new h2"),
-        &[current_hash_value[2].clone(), c]
+        &[current_hash_value[2].clone(), c],
     )?;
 
     let h3 = UInt32::addmany(
         cs.namespace(|| "new h3"),
-        &[current_hash_value[3].clone(), d]
+        &[current_hash_value[3].clone(), d],
     )?;
 
     let h4 = e.compute(
         cs.namespace(|| "deferred h4 computation"),
-        &[current_hash_value[4].clone()]
+        &[current_hash_value[4].clone()],
     )?;
 
     let h5 = UInt32::addmany(
         cs.namespace(|| "new h5"),
-        &[current_hash_value[5].clone(), f]
+        &[current_hash_value[5].clone(), f],
     )?;
 
     let h6 = UInt32::addmany(
         cs.namespace(|| "new h6"),
-        &[current_hash_value[6].clone(), g]
+        &[current_hash_value[6].clone(), g],
     )?;
 
     let h7 = UInt32::addmany(
         cs.namespace(|| "new h7"),
-        &[current_hash_value[7].clone(), h]
+        &[current_hash_value[7].clone(), h],
     )?;
 
     Ok(vec![h0, h1, h2, h3, h4, h5, h6, h7])
@@ -305,10 +264,11 @@ fn sha256_compression_function<E, CS>(
 #[cfg(test)]
 mod test {
     use super::*;
-    use circuit::boolean::AllocatedBit;
+    use crate::gadgets::boolean::AllocatedBit;
+    use crate::gadgets::test::TestConstraintSystem;
     use pairing::bls12_381::Bls12;
-    use circuit::test::TestConstraintSystem;
+    use rand_core::{RngCore, SeedableRng};
-    use rand::{XorShiftRng, SeedableRng, Rng};
+    use rand_xorshift::XorShiftRng;
 
     #[test]
     fn test_blank_hash() {
@@ -317,11 +277,7 @@ mod test {
         let mut cs = TestConstraintSystem::<Bls12>::new();
         let mut input_bits: Vec<_> = (0..512).map(|_| Boolean::Constant(false)).collect();
         input_bits[0] = Boolean::Constant(true);
-        let out = sha256_compression_function(
+        let out = sha256_compression_function(&mut cs, &input_bits, &iv).unwrap();
-            &mut cs,
-            &input_bits,
-            &iv
-        ).unwrap();
         let out_bits: Vec<_> = out.into_iter().flat_map(|e| e.into_bits_be()).collect();
 
         assert!(cs.is_satisfied());
@@ -341,25 +297,27 @@ mod test {
 
     #[test]
     fn test_full_block() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         let iv = get_sha256_iv();
 
         let mut cs = TestConstraintSystem::<Bls12>::new();
-        let input_bits: Vec<_> = (0..512).map(|i| {
+        let input_bits: Vec<_> = (0..512)
-            Boolean::from(
+            .map(|i| {
-                AllocatedBit::alloc(
+                Boolean::from(
-                    cs.namespace(|| format!("input bit {}", i)),
+                    AllocatedBit::alloc(
-                    Some(rng.gen())
+                        cs.namespace(|| format!("input bit {}", i)),
-                ).unwrap()
+                        Some(rng.next_u32() % 2 != 0),
-            )
+                    )
-        }).collect();
+                    .unwrap(),
+                )
+            })
+            .collect();
 
-        sha256_compression_function(
+        sha256_compression_function(cs.namespace(|| "sha256"), &input_bits, &iv).unwrap();
-            cs.namespace(|| "sha256"),
-            &input_bits,
-            &iv
-        ).unwrap();
 
         assert!(cs.is_satisfied());
         assert_eq!(cs.num_constraints() - 512, 25840);
@@ -367,18 +325,18 @@ mod test {
 
     #[test]
     fn test_against_vectors() {
-        use crypto::sha2::Sha256;
+        use sha2::{Digest, Sha256};
-        use crypto::digest::Digest;
 
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
-        for input_len in (0..32).chain((32..256).filter(|a| a % 8 == 0))
+        for input_len in (0..32).chain((32..256).filter(|a| a % 8 == 0)) {
-        {
             let mut h = Sha256::new();
-            let data: Vec<u8> = (0..input_len).map(|_| rng.gen()).collect();
+            let data: Vec<u8> = (0..input_len).map(|_| rng.next_u32() as u8).collect();
             h.input(&data);
-            let mut hash_result = [0u8; 32];
+            let hash_result = h.result();
-            h.result(&mut hash_result[..]);
 
             let mut cs = TestConstraintSystem::<Bls12>::new();
             let mut input_bits = vec![];
@@ -387,7 +345,11 @@ mod test {
                 for bit_i in (0..8).rev() {
                     let cs = cs.namespace(|| format!("input bit {} {}", byte_i, bit_i));
 
-                    input_bits.push(AllocatedBit::alloc(cs, Some((input_byte >> bit_i) & 1u8 == 1u8)).unwrap().into());
+                    input_bits.push(
+                        AllocatedBit::alloc(cs, Some((input_byte >> bit_i) & 1u8 == 1u8))
+                            .unwrap()
+                            .into(),
+                    );
                 }
             }
 
@@ -395,17 +357,19 @@ mod test {
 
             assert!(cs.is_satisfied());
 
-            let mut s = hash_result.as_ref().iter()
+            let mut s = hash_result
-                                            .flat_map(|&byte| (0..8).rev().map(move |i| (byte >> i) & 1u8 == 1u8));
+                .as_ref()
+                .iter()
+                .flat_map(|&byte| (0..8).rev().map(move |i| (byte >> i) & 1u8 == 1u8));
 
             for b in r {
                 match b {
                     Boolean::Is(b) => {
                         assert!(s.next().unwrap() == b.get_value().unwrap());
-                    },
+                    }
                     Boolean::Not(b) => {
                         assert!(s.next().unwrap() != b.get_value().unwrap());
-                    },
+                    }
                     Boolean::Constant(b) => {
                         assert!(input_len == 0);
                         assert!(s.next().unwrap() == b);

bellman/src/gadgets/test/mod.rs

@@ -1,17 +1,7 @@
-use pairing::{
+use ff::{Field, PrimeField, PrimeFieldRepr};
-    Engine,
+use pairing::Engine;
-    Field,
-    PrimeField,
-    PrimeFieldRepr
-};
 
-use bellman::{
+use crate::{ConstraintSystem, Index, LinearCombination, SynthesisError, Variable};
-    LinearCombination,
-    SynthesisError,
-    ConstraintSystem,
-    Variable,
-    Index
-};
 
 use std::collections::HashMap;
 use std::fmt::Write;
@@ -20,13 +10,13 @@ use byteorder::{BigEndian, ByteOrder};
 use std::cmp::Ordering;
 use std::collections::BTreeMap;
 
-use blake2_rfc::blake2s::Blake2s;
+use blake2s_simd::{Params as Blake2sParams, State as Blake2sState};
 
 #[derive(Debug)]
 enum NamedObject {
     Constraint(usize),
     Var(Variable),
-    Namespace
+    Namespace,
 }
 
 /// Constraint system for testing purposes.
@@ -37,10 +27,10 @@ pub struct TestConstraintSystem<E: Engine> {
         LinearCombination<E>,
         LinearCombination<E>,
         LinearCombination<E>,
-        String
+        String,
     )>,
     inputs: Vec<(E::Fr, String)>,
-    aux: Vec<(E::Fr, String)>
+    aux: Vec<(E::Fr, String)>,
 }
 
 #[derive(Clone, Copy)]
@@ -52,7 +42,7 @@ impl PartialEq for OrderedVariable {
         match (self.0.get_unchecked(), other.0.get_unchecked()) {
             (Index::Input(ref a), Index::Input(ref b)) => a == b,
             (Index::Aux(ref a), Index::Aux(ref b)) => a == b,
-            _ => false
+            _ => false,
         }
     }
 }
@@ -67,20 +57,17 @@ impl Ord for OrderedVariable {
             (Index::Input(ref a), Index::Input(ref b)) => a.cmp(b),
             (Index::Aux(ref a), Index::Aux(ref b)) => a.cmp(b),
             (Index::Input(_), Index::Aux(_)) => Ordering::Less,
-            (Index::Aux(_), Index::Input(_)) => Ordering::Greater
+            (Index::Aux(_), Index::Input(_)) => Ordering::Greater,
         }
     }
 }
 
-fn proc_lc<E: Engine>(
+fn proc_lc<E: Engine>(terms: &[(Variable, E::Fr)]) -> BTreeMap<OrderedVariable, E::Fr> {
-    terms: &[(Variable, E::Fr)],
-) -> BTreeMap<OrderedVariable, E::Fr>
-{
     let mut map = BTreeMap::new();
     for &(var, coeff) in terms {
         map.entry(OrderedVariable(var))
-           .or_insert(E::Fr::zero())
+            .or_insert(E::Fr::zero())
-           .add_assign(&coeff);
+            .add_assign(&coeff);
     }
 
     // Remove terms that have a zero coefficient to normalize
@@ -98,11 +85,7 @@ fn proc_lc<E: Engine>(
     map
 }
 
-fn hash_lc<E: Engine>(
+fn hash_lc<E: Engine>(terms: &[(Variable, E::Fr)], h: &mut Blake2sState) {
-    terms: &[(Variable, E::Fr)],
-    h: &mut Blake2s
-)
-{
     let map = proc_lc::<E>(terms);
 
     let mut buf = [0u8; 9 + 32];
@@ -114,13 +97,13 @@ fn hash_lc<E: Engine>(
             Index::Input(i) => {
                 buf[0] = b'I';
                 BigEndian::write_u64(&mut buf[1..9], i as u64);
-            },
+            }
             Index::Aux(i) => {
                 buf[0] = b'A';
                 BigEndian::write_u64(&mut buf[1..9], i as u64);
             }
         }
-        
+
         coeff.into_repr().write_be(&mut buf[9..]).unwrap();
 
         h.update(&buf);
@@ -130,15 +113,14 @@ fn hash_lc<E: Engine>(
 fn eval_lc<E: Engine>(
     terms: &[(Variable, E::Fr)],
     inputs: &[(E::Fr, String)],
-    aux: &[(E::Fr, String)]
+    aux: &[(E::Fr, String)],
-) -> E::Fr
+) -> E::Fr {
-{
     let mut acc = E::Fr::zero();
 
     for &(var, ref coeff) in terms {
         let mut tmp = match var.get_unchecked() {
             Index::Input(index) => inputs[index].0,
-            Index::Aux(index) => aux[index].0
+            Index::Aux(index) => aux[index].0,
         };
 
         tmp.mul_assign(&coeff);
@@ -151,14 +133,17 @@ fn eval_lc<E: Engine>(
 impl<E: Engine> TestConstraintSystem<E> {
     pub fn new() -> TestConstraintSystem<E> {
         let mut map = HashMap::new();
-        map.insert("ONE".into(), NamedObject::Var(TestConstraintSystem::<E>::one()));
+        map.insert(
+            "ONE".into(),
+            NamedObject::Var(TestConstraintSystem::<E>::one()),
+        );
 
         TestConstraintSystem {
             named_objects: map,
             current_namespace: vec![],
             constraints: vec![],
             inputs: vec![(E::Fr::one(), "ONE".into())],
-            aux: vec![]
+            aux: vec![],
         }
     }
 
@@ -171,9 +156,9 @@ impl<E: Engine> TestConstraintSystem<E> {
             tmp
         };
 
-        let powers_of_two = (0..E::Fr::NUM_BITS).map(|i| {
+        let powers_of_two = (0..E::Fr::NUM_BITS)
-            E::Fr::from_str("2").unwrap().pow(&[i as u64])
+            .map(|i| E::Fr::from_str("2").unwrap().pow(&[i as u64]))
-        }).collect::<Vec<_>>();
+            .collect::<Vec<_>>();
 
         let pp = |s: &mut String, lc: &LinearCombination<E>| {
             write!(s, "(").unwrap();
@@ -200,7 +185,7 @@ impl<E: Engine> TestConstraintSystem<E> {
                 match var.0.get_unchecked() {
                     Index::Input(i) => {
                         write!(s, "`{}`", &self.inputs[i].1).unwrap();
-                    },
+                    }
                     Index::Aux(i) => {
                         write!(s, "`{}`", &self.aux[i].1).unwrap();
                     }
@@ -230,7 +215,7 @@ impl<E: Engine> TestConstraintSystem<E> {
     }
 
     pub fn hash(&self) -> String {
-        let mut h = Blake2s::new(32);
+        let mut h = Blake2sParams::new().hash_length(32).to_state();
         {
             let mut buf = [0u8; 24];
 
@@ -263,45 +248,41 @@ impl<E: Engine> TestConstraintSystem<E> {
             a.mul_assign(&b);
 
             if a != c {
-                return Some(&*path)
+                return Some(&*path);
             }
         }
 
         None
     }
 
-    pub fn is_satisfied(&self) -> bool
+    pub fn is_satisfied(&self) -> bool {
-    {
         self.which_is_unsatisfied().is_none()
     }
 
-    pub fn num_constraints(&self) -> usize
+    pub fn num_constraints(&self) -> usize {
-    {
         self.constraints.len()
     }
 
-    pub fn set(&mut self, path: &str, to: E::Fr)
+    pub fn set(&mut self, path: &str, to: E::Fr) {
-    {
         match self.named_objects.get(path) {
-            Some(&NamedObject::Var(ref v)) => {
+            Some(&NamedObject::Var(ref v)) => match v.get_unchecked() {
-                match v.get_unchecked() {
+                Index::Input(index) => self.inputs[index].0 = to,
-                    Index::Input(index) => self.inputs[index].0 = to,
+                Index::Aux(index) => self.aux[index].0 = to,
-                    Index::Aux(index) => self.aux[index].0 = to
+            },
-                }
+            Some(e) => panic!(
-            }
+                "tried to set path `{}` to value, but `{:?}` already exists there.",
-            Some(e) => panic!("tried to set path `{}` to value, but `{:?}` already exists there.", path, e),
+                path, e
-            _ => panic!("no variable exists at path: {}", path)
+            ),
+            _ => panic!("no variable exists at path: {}", path),
         }
     }
 
-    pub fn verify(&self, expected: &[E::Fr]) -> bool
+    pub fn verify(&self, expected: &[E::Fr]) -> bool {
-    {
         assert_eq!(expected.len() + 1, self.inputs.len());
 
-        for (a, b) in self.inputs.iter().skip(1).zip(expected.iter())
+        for (a, b) in self.inputs.iter().skip(1).zip(expected.iter()) {
-        {
             if &a.0 != b {
-                return false
+                return false;
             }
         }
 
@@ -312,8 +293,7 @@ impl<E: Engine> TestConstraintSystem<E> {
         self.inputs.len()
     }
 
-    pub fn get_input(&mut self, index: usize, path: &str) -> E::Fr
+    pub fn get_input(&mut self, index: usize, path: &str) -> E::Fr {
-    {
         let (assignment, name) = self.inputs[index].clone();
 
         assert_eq!(path, name);
@@ -321,17 +301,17 @@ impl<E: Engine> TestConstraintSystem<E> {
         assignment
     }
 
-    pub fn get(&mut self, path: &str) -> E::Fr
+    pub fn get(&mut self, path: &str) -> E::Fr {
-    {
         match self.named_objects.get(path) {
-            Some(&NamedObject::Var(ref v)) => {
+            Some(&NamedObject::Var(ref v)) => match v.get_unchecked() {
-                match v.get_unchecked() {
+                Index::Input(index) => self.inputs[index].0,
-                    Index::Input(index) => self.inputs[index].0,
+                Index::Aux(index) => self.aux[index].0,
-                    Index::Aux(index) => self.aux[index].0
+            },
-                }
+            Some(e) => panic!(
-            }
+                "tried to get value of path `{}`, but `{:?}` exists there (not a variable)",
-            Some(e) => panic!("tried to get value of path `{}`, but `{:?}` exists there (not a variable)", path, e),
+                path, e
-            _ => panic!("no variable exists at path: {}", path)
+            ),
+            _ => panic!("no variable exists at path: {}", path),
         }
     }
 
@@ -352,8 +332,7 @@ fn compute_path(ns: &[String], this: String) -> String {
     let mut name = String::new();
 
     let mut needs_separation = false;
-    for ns in ns.iter().chain(Some(&this).into_iter())
+    for ns in ns.iter().chain(Some(&this).into_iter()) {
-    {
         if needs_separation {
             name += "/";
         }
@@ -368,12 +347,11 @@ fn compute_path(ns: &[String], this: String) -> String {
 impl<E: Engine> ConstraintSystem<E> for TestConstraintSystem<E> {
     type Root = Self;
 
-    fn alloc<F, A, AR>(
+    fn alloc<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         let index = self.aux.len();
         let path = compute_path(&self.current_namespace, annotation().into());
@@ -384,12 +362,11 @@ impl<E: Engine> ConstraintSystem<E> for TestConstraintSystem<E> {
         Ok(var)
     }
 
-    fn alloc_input<F, A, AR>(
+    fn alloc_input<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         let index = self.inputs.len();
         let path = compute_path(&self.current_namespace, annotation().into());
@@ -400,17 +377,13 @@ impl<E: Engine> ConstraintSystem<E> for TestConstraintSystem<E> {
         Ok(var)
     }
 
-    fn enforce<A, AR, LA, LB, LC>(
+    fn enforce<A, AR, LA, LB, LC>(&mut self, annotation: A, a: LA, b: LB, c: LC)
-        &mut self,
+    where
-        annotation: A,
+        A: FnOnce() -> AR,
-        a: LA,
+        AR: Into<String>,
-        b: LB,
+        LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        c: LC
+        LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-    )
+        LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        where A: FnOnce() -> AR, AR: Into<String>,
-              LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>
     {
         let path = compute_path(&self.current_namespace, annotation().into());
         let index = self.constraints.len();
@@ -424,7 +397,9 @@ impl<E: Engine> ConstraintSystem<E> for TestConstraintSystem<E> {
     }
 
     fn push_namespace<NR, N>(&mut self, name_fn: N)
-    where NR: Into<String>, N: FnOnce() -> NR
+    where
+        NR: Into<String>,
+        N: FnOnce() -> NR,
     {
         let name = name_fn().into();
         let path = compute_path(&self.current_namespace, name.clone());
@@ -432,47 +407,43 @@ impl<E: Engine> ConstraintSystem<E> for TestConstraintSystem<E> {
         self.current_namespace.push(name);
     }
 
-    fn pop_namespace(&mut self)
+    fn pop_namespace(&mut self) {
-    {
         assert!(self.current_namespace.pop().is_some());
     }
 
-    fn get_root(&mut self) -> &mut Self::Root
+    fn get_root(&mut self) -> &mut Self::Root {
-    {
         self
     }
 }
 
 #[test]
 fn test_cs() {
+    use ff::PrimeField;
     use pairing::bls12_381::{Bls12, Fr};
-    use pairing::PrimeField;
 
     let mut cs = TestConstraintSystem::<Bls12>::new();
     assert!(cs.is_satisfied());
     assert_eq!(cs.num_constraints(), 0);
-    let a = cs.namespace(|| "a").alloc(|| "var", || Ok(Fr::from_str("10").unwrap())).unwrap();
+    let a = cs
-    let b = cs.namespace(|| "b").alloc(|| "var", || Ok(Fr::from_str("4").unwrap())).unwrap();
+        .namespace(|| "a")
-    let c = cs.alloc(|| "product", || Ok(Fr::from_str("40").unwrap())).unwrap();
+        .alloc(|| "var", || Ok(Fr::from_str("10").unwrap()))
+        .unwrap();
+    let b = cs
+        .namespace(|| "b")
+        .alloc(|| "var", || Ok(Fr::from_str("4").unwrap()))
+        .unwrap();
+    let c = cs
+        .alloc(|| "product", || Ok(Fr::from_str("40").unwrap()))
+        .unwrap();
 
-    cs.enforce(
+    cs.enforce(|| "mult", |lc| lc + a, |lc| lc + b, |lc| lc + c);
-        || "mult",
-        |lc| lc + a,
-        |lc| lc + b,
-        |lc| lc + c
-    );
     assert!(cs.is_satisfied());
     assert_eq!(cs.num_constraints(), 1);
 
     cs.set("a/var", Fr::from_str("4").unwrap());
 
     let one = TestConstraintSystem::<Bls12>::one();
-    cs.enforce(
+    cs.enforce(|| "eq", |lc| lc + a, |lc| lc + one, |lc| lc + b);
-        || "eq",
-        |lc| lc + a,
-        |lc| lc + one,
-        |lc| lc + b
-    );
 
     assert!(!cs.is_satisfied());
     assert!(cs.which_is_unsatisfied() == Some("mult"));

bellman/src/gadgets/uint32.rs

@@ -1,19 +1,9 @@
-use pairing::{
+use ff::{Field, PrimeField};
-    Engine,
+use pairing::Engine;
-    Field,
-    PrimeField
-};
 
-use bellman::{
+use crate::{ConstraintSystem, LinearCombination, SynthesisError};
-    SynthesisError,
-    ConstraintSystem,
-    LinearCombination
-};
 
-use super::boolean::{
+use super::boolean::{AllocatedBit, Boolean};
-    Boolean,
-    AllocatedBit
-};
 
 use super::multieq::MultiEq;
 
@@ -23,13 +13,12 @@ use super::multieq::MultiEq;
 pub struct UInt32 {
     // Least significant bit first
     bits: Vec<Boolean>,
-    value: Option<u32>
+    value: Option<u32>,
 }
 
 impl UInt32 {
     /// Construct a constant `UInt32` from a `u32`
-    pub fn constant(value: u32) -> Self
+    pub fn constant(value: u32) -> Self {
-    {
         let mut bits = Vec::with_capacity(32);
 
         let mut tmp = value;
@@ -45,17 +34,15 @@ impl UInt32 {
 
         UInt32 {
             bits: bits,
-            value: Some(value)
+            value: Some(value),
         }
     }
 
     /// Allocate a `UInt32` in the constraint system
-    pub fn alloc<E, CS>(
+    pub fn alloc<E, CS>(mut cs: CS, value: Option<u32>) -> Result<Self, SynthesisError>
-        mut cs: CS,
+    where
-        value: Option<u32>
+        E: Engine,
-    ) -> Result<Self, SynthesisError>
+        CS: ConstraintSystem<E>,
-        where E: Engine,
-              CS: ConstraintSystem<E>
     {
         let values = match value {
             Some(mut val) => {
@@ -67,23 +54,24 @@ impl UInt32 {
                 }
 
                 v
-            },
+            }
-            None => vec![None; 32]
+            None => vec![None; 32],
         };
 
-        let bits = values.into_iter()
+        let bits = values
-                         .enumerate()
+            .into_iter()
-                         .map(|(i, v)| {
+            .enumerate()
-                            Ok(Boolean::from(AllocatedBit::alloc(
+            .map(|(i, v)| {
-                                cs.namespace(|| format!("allocated bit {}", i)),
+                Ok(Boolean::from(AllocatedBit::alloc(
-                                v
+                    cs.namespace(|| format!("allocated bit {}", i)),
-                            )?))
+                    v,
-                         })
+                )?))
-                         .collect::<Result<Vec<_>, SynthesisError>>()?;
+            })
+            .collect::<Result<Vec<_>, SynthesisError>>()?;
 
         Ok(UInt32 {
             bits: bits,
-            value: value
+            value: value,
         })
     }
 
@@ -99,19 +87,22 @@ impl UInt32 {
             value.as_mut().map(|v| *v <<= 1);
 
             match b.get_value() {
-                Some(true) => { value.as_mut().map(|v| *v |= 1); },
+                Some(true) => {
-                Some(false) => {},
+                    value.as_mut().map(|v| *v |= 1);
-                None => { value = None; }
+                }
+                Some(false) => {}
+                None => {
+                    value = None;
+                }
             }
         }
 
         UInt32 {
             value: value,
-            bits: bits.iter().rev().cloned().collect()
+            bits: bits.iter().rev().cloned().collect(),
         }
     }
 
-
     /// Turns this `UInt32` into its little-endian byte order representation.
     pub fn into_bits(&self) -> Vec<Boolean> {
         self.bits.clone()
@@ -119,8 +110,7 @@ impl UInt32 {
 
     /// Converts a little-endian byte order representation of bits into a
     /// `UInt32`.
-    pub fn from_bits(bits: &[Boolean]) -> Self
+    pub fn from_bits(bits: &[Boolean]) -> Self {
-    {
         assert_eq!(bits.len(), 32);
 
         let new_bits = bits.to_vec();
@@ -134,43 +124,45 @@ impl UInt32 {
                     if b {
                         value.as_mut().map(|v| *v |= 1);
                     }
-                },
-                &Boolean::Is(ref b) => {
-                    match b.get_value() {
-                        Some(true) => { value.as_mut().map(|v| *v |= 1); },
-                        Some(false) => {},
-                        None => { value = None }
-                    }
-                },
-                &Boolean::Not(ref b) => {
-                    match b.get_value() {
-                        Some(false) => { value.as_mut().map(|v| *v |= 1); },
-                        Some(true) => {},
-                        None => { value = None }
-                    }
                 }
+                &Boolean::Is(ref b) => match b.get_value() {
+                    Some(true) => {
+                        value.as_mut().map(|v| *v |= 1);
+                    }
+                    Some(false) => {}
+                    None => value = None,
+                },
+                &Boolean::Not(ref b) => match b.get_value() {
+                    Some(false) => {
+                        value.as_mut().map(|v| *v |= 1);
+                    }
+                    Some(true) => {}
+                    None => value = None,
+                },
             }
         }
 
         UInt32 {
             value: value,
-            bits: new_bits
+            bits: new_bits,
         }
     }
 
     pub fn rotr(&self, by: usize) -> Self {
         let by = by % 32;
 
-        let new_bits = self.bits.iter()
+        let new_bits = self
-                                .skip(by)
+            .bits
-                                .chain(self.bits.iter())
+            .iter()
-                                .take(32)
+            .skip(by)
-                                .cloned()
+            .chain(self.bits.iter())
-                                .collect();
+            .take(32)
+            .cloned()
+            .collect();
 
         UInt32 {
             bits: new_bits,
-            value: self.value.map(|v| v.rotate_right(by as u32))
+            value: self.value.map(|v| v.rotate_right(by as u32)),
         }
     }
 
@@ -179,17 +171,18 @@ impl UInt32 {
 
         let fill = Boolean::constant(false);
 
-        let new_bits = self.bits
+        let new_bits = self
-                           .iter() // The bits are least significant first
+            .bits
-                           .skip(by) // Skip the bits that will be lost during the shift
+            .iter() // The bits are least significant first
-                           .chain(Some(&fill).into_iter().cycle()) // Rest will be zeros
+            .skip(by) // Skip the bits that will be lost during the shift
-                           .take(32) // Only 32 bits needed!
+            .chain(Some(&fill).into_iter().cycle()) // Rest will be zeros
-                           .cloned()
+            .take(32) // Only 32 bits needed!
-                           .collect();
+            .cloned()
+            .collect();
 
         UInt32 {
             bits: new_bits,
-            value: self.value.map(|v| v >> by as u32)
+            value: self.value.map(|v| v >> by as u32),
         }
     }
 
@@ -199,121 +192,99 @@ impl UInt32 {
         b: &Self,
         c: &Self,
         tri_fn: F,
-        circuit_fn: U
+        circuit_fn: U,
     ) -> Result<Self, SynthesisError>
-        where E: Engine,
+    where
-              CS: ConstraintSystem<E>,
+        E: Engine,
-              F: Fn(u32, u32, u32) -> u32,
+        CS: ConstraintSystem<E>,
-              U: Fn(&mut CS, usize, &Boolean, &Boolean, &Boolean) -> Result<Boolean, SynthesisError>
+        F: Fn(u32, u32, u32) -> u32,
+        U: Fn(&mut CS, usize, &Boolean, &Boolean, &Boolean) -> Result<Boolean, SynthesisError>,
     {
         let new_value = match (a.value, b.value, c.value) {
-            (Some(a), Some(b), Some(c)) => {
+            (Some(a), Some(b), Some(c)) => Some(tri_fn(a, b, c)),
-                Some(tri_fn(a, b, c))
+            _ => None,
-            },
-            _ => None
         };
 
-        let bits = a.bits.iter()
+        let bits = a
-                            .zip(b.bits.iter())
+            .bits
-                            .zip(c.bits.iter())
+            .iter()
-                            .enumerate()
+            .zip(b.bits.iter())
-                            .map(|(i, ((a, b), c))| circuit_fn(&mut cs, i, a, b, c))
+            .zip(c.bits.iter())
-                            .collect::<Result<_, _>>()?;
+            .enumerate()
+            .map(|(i, ((a, b), c))| circuit_fn(&mut cs, i, a, b, c))
+            .collect::<Result<_, _>>()?;
 
         Ok(UInt32 {
             bits: bits,
-            value: new_value
+            value: new_value,
         })
     }
 
     /// Compute the `maj` value (a and b) xor (a and c) xor (b and c)
     /// during SHA256.
-    pub fn sha256_maj<E, CS>(
+    pub fn sha256_maj<E, CS>(cs: CS, a: &Self, b: &Self, c: &Self) -> Result<Self, SynthesisError>
-        cs: CS,
+    where
-        a: &Self,
+        E: Engine,
-        b: &Self,
+        CS: ConstraintSystem<E>,
-        c: &Self
-    ) -> Result<Self, SynthesisError>
-        where E: Engine,
-              CS: ConstraintSystem<E>
     {
-        Self::triop(cs, a, b, c, |a, b, c| (a & b) ^ (a & c) ^ (b & c),
+        Self::triop(
-            |cs, i, a, b, c| {
+            cs,
-                Boolean::sha256_maj(
+            a,
-                    cs.namespace(|| format!("maj {}", i)),
+            b,
-                    a,
+            c,
-                    b,
+            |a, b, c| (a & b) ^ (a & c) ^ (b & c),
-                    c
+            |cs, i, a, b, c| Boolean::sha256_maj(cs.namespace(|| format!("maj {}", i)), a, b, c),
-                )
-            }
         )
     }
 
     /// Compute the `ch` value `(a and b) xor ((not a) and c)`
     /// during SHA256.
-    pub fn sha256_ch<E, CS>(
+    pub fn sha256_ch<E, CS>(cs: CS, a: &Self, b: &Self, c: &Self) -> Result<Self, SynthesisError>
-        cs: CS,
+    where
-        a: &Self,
+        E: Engine,
-        b: &Self,
+        CS: ConstraintSystem<E>,
-        c: &Self
-    ) -> Result<Self, SynthesisError>
-        where E: Engine,
-              CS: ConstraintSystem<E>
     {
-        Self::triop(cs, a, b, c, |a, b, c| (a & b) ^ ((!a) & c),
+        Self::triop(
-            |cs, i, a, b, c| {
+            cs,
-                Boolean::sha256_ch(
+            a,
-                    cs.namespace(|| format!("ch {}", i)),
+            b,
-                    a,
+            c,
-                    b,
+            |a, b, c| (a & b) ^ ((!a) & c),
-                    c
+            |cs, i, a, b, c| Boolean::sha256_ch(cs.namespace(|| format!("ch {}", i)), a, b, c),
-                )
-            }
         )
     }
 
     /// XOR this `UInt32` with another `UInt32`
-    pub fn xor<E, CS>(
+    pub fn xor<E, CS>(&self, mut cs: CS, other: &Self) -> Result<Self, SynthesisError>
-        &self,
+    where
-        mut cs: CS,
+        E: Engine,
-        other: &Self
+        CS: ConstraintSystem<E>,
-    ) -> Result<Self, SynthesisError>
-        where E: Engine,
-              CS: ConstraintSystem<E>
     {
         let new_value = match (self.value, other.value) {
-            (Some(a), Some(b)) => {
+            (Some(a), Some(b)) => Some(a ^ b),
-                Some(a ^ b)
+            _ => None,
-            },
-            _ => None
         };
 
-        let bits = self.bits.iter()
+        let bits = self
-                            .zip(other.bits.iter())
+            .bits
-                            .enumerate()
+            .iter()
-                            .map(|(i, (a, b))| {
+            .zip(other.bits.iter())
-                                Boolean::xor(
+            .enumerate()
-                                    cs.namespace(|| format!("xor of bit {}", i)),
+            .map(|(i, (a, b))| Boolean::xor(cs.namespace(|| format!("xor of bit {}", i)), a, b))
-                                    a,
+            .collect::<Result<_, _>>()?;
-                                    b
-                                )
-                            })
-                            .collect::<Result<_, _>>()?;
 
         Ok(UInt32 {
             bits: bits,
-            value: new_value
+            value: new_value,
         })
     }
 
     /// Perform modular addition of several `UInt32` objects.
-    pub fn addmany<E, CS, M>(
+    pub fn addmany<E, CS, M>(mut cs: M, operands: &[Self]) -> Result<Self, SynthesisError>
-        mut cs: M,
+    where
-        operands: &[Self]
+        E: Engine,
-    ) -> Result<Self, SynthesisError>
+        CS: ConstraintSystem<E>,
-        where E: Engine,
+        M: ConstraintSystem<E, Root = MultiEq<E, CS>>,
-              CS: ConstraintSystem<E>,
-              M: ConstraintSystem<E, Root=MultiEq<E, CS>>
     {
         // Make some arbitrary bounds for ourselves to avoid overflows
         // in the scalar field
@@ -340,7 +311,7 @@ impl UInt32 {
             match op.value {
                 Some(val) => {
                     result_value.as_mut().map(|v| *v += val as u64);
-                },
+                }
                 None => {
                     // If any of our operands have unknown value, we won't
                     // know the value of the result
@@ -384,7 +355,7 @@ impl UInt32 {
             // Allocate the bit
             let b = AllocatedBit::alloc(
                 cs.namespace(|| format!("result bit {}", i)),
-                result_value.map(|v| (v >> i) & 1 == 1)
+                result_value.map(|v| (v >> i) & 1 == 1),
             )?;
 
             // Add this bit to the result combination
@@ -405,28 +376,34 @@ impl UInt32 {
 
         Ok(UInt32 {
             bits: result_bits,
-            value: modular_value
+            value: modular_value,
         })
     }
 }
 
 #[cfg(test)]
 mod test {
-    use rand::{XorShiftRng, SeedableRng, Rng};
+    use super::UInt32;
-    use ::circuit::boolean::{Boolean};
+    use crate::gadgets::boolean::Boolean;
-    use super::{UInt32};
+    use crate::gadgets::multieq::MultiEq;
-    use pairing::bls12_381::{Bls12};
+    use crate::gadgets::test::*;
-    use pairing::{Field};
+    use crate::ConstraintSystem;
-    use ::circuit::test::*;
+    use ff::Field;
-    use bellman::{ConstraintSystem};
+    use pairing::bls12_381::Bls12;
-    use circuit::multieq::MultiEq;
+    use rand_core::{RngCore, SeedableRng};
+    use rand_xorshift::XorShiftRng;
 
     #[test]
     fn test_uint32_from_bits_be() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0653]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..1000 {
-            let mut v = (0..32).map(|_| Boolean::constant(rng.gen())).collect::<Vec<_>>();
+            let mut v = (0..32)
+                .map(|_| Boolean::constant(rng.next_u32() % 2 != 0))
+                .collect::<Vec<_>>();
 
             let b = UInt32::from_bits_be(&v);
 
@@ -434,19 +411,18 @@ mod test {
                 match bit {
                     &Boolean::Constant(bit) => {
                         assert!(bit == ((b.value.unwrap() >> i) & 1 == 1));
-                    },
+                    }
-                    _ => unreachable!()
+                    _ => unreachable!(),
                 }
             }
 
             let expected_to_be_same = b.into_bits_be();
 
-            for x in v.iter().zip(expected_to_be_same.iter())
+            for x in v.iter().zip(expected_to_be_same.iter()) {
-            {
                 match x {
-                    (&Boolean::Constant(true), &Boolean::Constant(true)) => {},
+                    (&Boolean::Constant(true), &Boolean::Constant(true)) => {}
-                    (&Boolean::Constant(false), &Boolean::Constant(false)) => {},
+                    (&Boolean::Constant(false), &Boolean::Constant(false)) => {}
-                    _ => unreachable!()
+                    _ => unreachable!(),
                 }
             }
         }
@@ -454,10 +430,15 @@ mod test {
 
     #[test]
     fn test_uint32_from_bits() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0653]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..1000 {
-            let mut v = (0..32).map(|_| Boolean::constant(rng.gen())).collect::<Vec<_>>();
+            let mut v = (0..32)
+                .map(|_| Boolean::constant(rng.next_u32() % 2 != 0))
+                .collect::<Vec<_>>();
 
             let b = UInt32::from_bits(&v);
 
@@ -465,19 +446,18 @@ mod test {
                 match bit {
                     &Boolean::Constant(bit) => {
                         assert!(bit == ((b.value.unwrap() >> i) & 1 == 1));
-                    },
+                    }
-                    _ => unreachable!()
+                    _ => unreachable!(),
                 }
             }
 
             let expected_to_be_same = b.into_bits();
 
-            for x in v.iter().zip(expected_to_be_same.iter())
+            for x in v.iter().zip(expected_to_be_same.iter()) {
-            {
                 match x {
-                    (&Boolean::Constant(true), &Boolean::Constant(true)) => {},
+                    (&Boolean::Constant(true), &Boolean::Constant(true)) => {}
-                    (&Boolean::Constant(false), &Boolean::Constant(false)) => {},
+                    (&Boolean::Constant(false), &Boolean::Constant(false)) => {}
-                    _ => unreachable!()
+                    _ => unreachable!(),
                 }
             }
         }
@@ -485,14 +465,17 @@ mod test {
 
     #[test]
     fn test_uint32_xor() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0653]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..1000 {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a: u32 = rng.gen();
+            let a = rng.next_u32();
-            let b: u32 = rng.gen();
+            let b = rng.next_u32();
-            let c: u32 = rng.gen();
+            let c = rng.next_u32();
 
             let mut expected = a ^ b ^ c;
 
@@ -511,10 +494,10 @@ mod test {
                 match b {
                     &Boolean::Is(ref b) => {
                         assert!(b.get_value().unwrap() == (expected & 1 == 1));
-                    },
+                    }
                     &Boolean::Not(ref b) => {
                         assert!(!b.get_value().unwrap() == (expected & 1 == 1));
-                    },
+                    }
                     &Boolean::Constant(b) => {
                         assert!(b == (expected & 1 == 1));
                     }
@@ -527,14 +510,17 @@ mod test {
 
     #[test]
     fn test_uint32_addmany_constants() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..1000 {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a: u32 = rng.gen();
+            let a = rng.next_u32();
-            let b: u32 = rng.gen();
+            let b = rng.next_u32();
-            let c: u32 = rng.gen();
+            let c = rng.next_u32();
 
             let a_bit = UInt32::constant(a);
             let b_bit = UInt32::constant(b);
@@ -544,7 +530,8 @@ mod test {
 
             let r = {
                 let mut cs = MultiEq::new(&mut cs);
-                let r = UInt32::addmany(cs.namespace(|| "addition"), &[a_bit, b_bit, c_bit]).unwrap();
+                let r =
+                    UInt32::addmany(cs.namespace(|| "addition"), &[a_bit, b_bit, c_bit]).unwrap();
                 r
             };
 
@@ -566,15 +553,18 @@ mod test {
 
     #[test]
     fn test_uint32_addmany() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..1000 {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a: u32 = rng.gen();
+            let a = rng.next_u32();
-            let b: u32 = rng.gen();
+            let b = rng.next_u32();
-            let c: u32 = rng.gen();
+            let c = rng.next_u32();
-            let d: u32 = rng.gen();
+            let d = rng.next_u32();
 
             let mut expected = (a ^ b).wrapping_add(c).wrapping_add(d);
 
@@ -598,13 +588,11 @@ mod test {
                 match b {
                     &Boolean::Is(ref b) => {
                         assert!(b.get_value().unwrap() == (expected & 1 == 1));
-                    },
+                    }
                     &Boolean::Not(ref b) => {
                         assert!(!b.get_value().unwrap() == (expected & 1 == 1));
-                    },
-                    &Boolean::Constant(_) => {
-                        unreachable!()
                     }
+                    &Boolean::Constant(_) => unreachable!(),
                 }
 
                 expected >>= 1;
@@ -623,9 +611,12 @@ mod test {
 
     #[test]
     fn test_uint32_rotr() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
-        let mut num = rng.gen();
+        let mut num = rng.next_u32();
 
         let a = UInt32::constant(num);
 
@@ -640,8 +631,8 @@ mod test {
                 match b {
                     &Boolean::Constant(b) => {
                         assert_eq!(b, tmp & 1 == 1);
-                    },
+                    }
-                    _ => unreachable!()
+                    _ => unreachable!(),
                 }
 
                 tmp >>= 1;
@@ -653,15 +644,18 @@ mod test {
 
     #[test]
     fn test_uint32_shr() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..50 {
             for i in 0..60 {
-                let num = rng.gen();
+                let num = rng.next_u32();
                 let a = UInt32::constant(num).shr(i);
-                let b = UInt32::constant(num >> i);
+                let b = UInt32::constant(num.wrapping_shr(i as u32));
 
-                assert_eq!(a.value.unwrap(), num >> i);
+                assert_eq!(a.value.unwrap(), num.wrapping_shr(i as u32));
 
                 assert_eq!(a.bits.len(), b.bits.len());
                 for (a, b) in a.bits.iter().zip(b.bits.iter()) {
@@ -673,14 +667,17 @@ mod test {
 
     #[test]
     fn test_uint32_sha256_maj() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0653]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..1000 {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a: u32 = rng.gen();
+            let a = rng.next_u32();
-            let b: u32 = rng.gen();
+            let b = rng.next_u32();
-            let c: u32 = rng.gen();
+            let c = rng.next_u32();
 
             let mut expected = (a & b) ^ (a & c) ^ (b & c);
 
@@ -698,10 +695,10 @@ mod test {
                 match b {
                     &Boolean::Is(ref b) => {
                         assert!(b.get_value().unwrap() == (expected & 1 == 1));
-                    },
+                    }
                     &Boolean::Not(ref b) => {
                         assert!(!b.get_value().unwrap() == (expected & 1 == 1));
-                    },
+                    }
                     &Boolean::Constant(b) => {
                         assert!(b == (expected & 1 == 1));
                     }
@@ -714,14 +711,17 @@ mod test {
 
     #[test]
     fn test_uint32_sha256_ch() {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0653]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..1000 {
             let mut cs = TestConstraintSystem::<Bls12>::new();
 
-            let a: u32 = rng.gen();
+            let a = rng.next_u32();
-            let b: u32 = rng.gen();
+            let b = rng.next_u32();
-            let c: u32 = rng.gen();
+            let c = rng.next_u32();
 
             let mut expected = (a & b) ^ ((!a) & c);
 
@@ -739,10 +739,10 @@ mod test {
                 match b {
                     &Boolean::Is(ref b) => {
                         assert!(b.get_value().unwrap() == (expected & 1 == 1));
-                    },
+                    }
                     &Boolean::Not(ref b) => {
                         assert!(!b.get_value().unwrap() == (expected & 1 == 1));
-                    },
+                    }
                     &Boolean::Constant(b) => {
                         assert!(b == (expected & 1 == 1));
                     }

bellman/src/groth16/generator.rs

@@ -1,65 +1,39 @@
-use rand::Rng;
+use rand_core::RngCore;
 
 use std::sync::Arc;
 
-use pairing::{
+use ff::{Field, PrimeField};
-    Engine,
+use group::{CurveAffine, CurveProjective, Wnaf};
-    PrimeField,
+use pairing::Engine;
-    Field,
-    Wnaf,
-    CurveProjective,
-    CurveAffine
-};
 
-use super::{
+use super::{Parameters, VerifyingKey};
-    Parameters,
-    VerifyingKey
-};
 
-use ::{
+use {Circuit, ConstraintSystem, Index, LinearCombination, SynthesisError, Variable};
-    SynthesisError,
-    Circuit,
-    ConstraintSystem,
-    LinearCombination,
-    Variable,
-    Index
-};
 
-use ::domain::{
+use domain::{EvaluationDomain, Scalar};
-    EvaluationDomain,
-    Scalar
-};
 
-use ::multicore::{
+use multicore::Worker;
-    Worker
-};
 
 /// Generates a random common reference string for
 /// a circuit.
 pub fn generate_random_parameters<E, C, R>(
     circuit: C,
-    rng: &mut R
+    rng: &mut R,
 ) -> Result<Parameters<E>, SynthesisError>
-    where E: Engine, C: Circuit<E>, R: Rng
+where
+    E: Engine,
+    C: Circuit<E>,
+    R: RngCore,
 {
-    let g1 = rng.gen();
+    let g1 = E::G1::random(rng);
-    let g2 = rng.gen();
+    let g2 = E::G2::random(rng);
-    let alpha = rng.gen();
+    let alpha = E::Fr::random(rng);
-    let beta = rng.gen();
+    let beta = E::Fr::random(rng);
-    let gamma = rng.gen();
+    let gamma = E::Fr::random(rng);
-    let delta = rng.gen();
+    let delta = E::Fr::random(rng);
-    let tau = rng.gen();
+    let tau = E::Fr::random(rng);
 
-    generate_parameters::<E, C>(
+    generate_parameters::<E, C>(circuit, g1, g2, alpha, beta, gamma, delta, tau)
-        circuit,
-        g1,
-        g2,
-        alpha,
-        beta,
-        gamma,
-        delta,
-        tau
-    )
 }
 
 /// This is our assembly structure that we'll use to synthesize the
@@ -73,18 +47,17 @@ struct KeypairAssembly<E: Engine> {
     ct_inputs: Vec<Vec<(E::Fr, usize)>>,
     at_aux: Vec<Vec<(E::Fr, usize)>>,
     bt_aux: Vec<Vec<(E::Fr, usize)>>,
-    ct_aux: Vec<Vec<(E::Fr, usize)>>
+    ct_aux: Vec<Vec<(E::Fr, usize)>>,
 }
 
 impl<E: Engine> ConstraintSystem<E> for KeypairAssembly<E> {
     type Root = Self;
 
-    fn alloc<F, A, AR>(
+    fn alloc<F, A, AR>(&mut self, _: A, _: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        _: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        _: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         // There is no assignment, so we don't even invoke the
         // function for obtaining one.
@@ -99,12 +72,11 @@ impl<E: Engine> ConstraintSystem<E> for KeypairAssembly<E> {
         Ok(Variable(Index::Aux(index)))
     }
 
-    fn alloc_input<F, A, AR>(
+    fn alloc_input<F, A, AR>(&mut self, _: A, _: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        _: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        _: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         // There is no assignment, so we don't even invoke the
         // function for obtaining one.
@@ -119,48 +91,59 @@ impl<E: Engine> ConstraintSystem<E> for KeypairAssembly<E> {
         Ok(Variable(Index::Input(index)))
     }
 
-    fn enforce<A, AR, LA, LB, LC>(
+    fn enforce<A, AR, LA, LB, LC>(&mut self, _: A, a: LA, b: LB, c: LC)
-        &mut self,
+    where
-        _: A,
+        A: FnOnce() -> AR,
-        a: LA,
+        AR: Into<String>,
-        b: LB,
+        LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        c: LC
+        LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-    )
+        LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        where A: FnOnce() -> AR, AR: Into<String>,
-              LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>
     {
         fn eval<E: Engine>(
             l: LinearCombination<E>,
             inputs: &mut [Vec<(E::Fr, usize)>],
             aux: &mut [Vec<(E::Fr, usize)>],
-            this_constraint: usize
+            this_constraint: usize,
-        )
+        ) {
-        {
             for (index, coeff) in l.0 {
                 match index {
                     Variable(Index::Input(id)) => inputs[id].push((coeff, this_constraint)),
-                    Variable(Index::Aux(id)) => aux[id].push((coeff, this_constraint))
+                    Variable(Index::Aux(id)) => aux[id].push((coeff, this_constraint)),
                 }
             }
         }
 
-        eval(a(LinearCombination::zero()), &mut self.at_inputs, &mut self.at_aux, self.num_constraints);
+        eval(
-        eval(b(LinearCombination::zero()), &mut self.bt_inputs, &mut self.bt_aux, self.num_constraints);
+            a(LinearCombination::zero()),
-        eval(c(LinearCombination::zero()), &mut self.ct_inputs, &mut self.ct_aux, self.num_constraints);
+            &mut self.at_inputs,
+            &mut self.at_aux,
+            self.num_constraints,
+        );
+        eval(
+            b(LinearCombination::zero()),
+            &mut self.bt_inputs,
+            &mut self.bt_aux,
+            self.num_constraints,
+        );
+        eval(
+            c(LinearCombination::zero()),
+            &mut self.ct_inputs,
+            &mut self.ct_aux,
+            self.num_constraints,
+        );
 
         self.num_constraints += 1;
     }
 
     fn push_namespace<NR, N>(&mut self, _: N)
-        where NR: Into<String>, N: FnOnce() -> NR
+    where
+        NR: Into<String>,
+        N: FnOnce() -> NR,
     {
         // Do nothing; we don't care about namespaces in this context.
     }
 
-    fn pop_namespace(&mut self)
+    fn pop_namespace(&mut self) {
-    {
         // Do nothing; we don't care about namespaces in this context.
     }
 
@@ -178,9 +161,11 @@ pub fn generate_parameters<E, C>(
     beta: E::Fr,
     gamma: E::Fr,
     delta: E::Fr,
-    tau: E::Fr
+    tau: E::Fr,
 ) -> Result<Parameters<E>, SynthesisError>
-    where E: Engine, C: Circuit<E>
+where
+    E: Engine,
+    C: Circuit<E>,
 {
     let mut assembly = KeypairAssembly {
         num_inputs: 0,
@@ -191,7 +176,7 @@ pub fn generate_parameters<E, C>(
         ct_inputs: vec![],
         at_aux: vec![],
         bt_aux: vec![],
-        ct_aux: vec![]
+        ct_aux: vec![],
     };
 
     // Allocate the "one" input variable
@@ -203,11 +188,7 @@ pub fn generate_parameters<E, C>(
     // Input constraints to ensure full density of IC query
     // x * 0 = 0
     for i in 0..assembly.num_inputs {
-        assembly.enforce(|| "",
+        assembly.enforce(|| "", |lc| lc + Variable(Index::Input(i)), |lc| lc, |lc| lc);
-            |lc| lc + Variable(Index::Input(i)),
-            |lc| lc,
-            |lc| lc,
-        );
     }
 
     // Create bases for blind evaluation of polynomials at tau
@@ -245,10 +226,9 @@ pub fn generate_parameters<E, C>(
         {
             let powers_of_tau = powers_of_tau.as_mut();
             worker.scope(powers_of_tau.len(), |scope, chunk| {
-                for (i, powers_of_tau) in powers_of_tau.chunks_mut(chunk).enumerate()
+                for (i, powers_of_tau) in powers_of_tau.chunks_mut(chunk).enumerate() {
-                {
                     scope.spawn(move || {
-                        let mut current_tau_power = tau.pow(&[(i*chunk) as u64]);
+                        let mut current_tau_power = tau.pow(&[(i * chunk) as u64]);
 
                         for p in powers_of_tau {
                             p.0 = current_tau_power;
@@ -265,14 +245,15 @@ pub fn generate_parameters<E, C>(
 
         // Compute the H query with multiple threads
         worker.scope(h.len(), |scope, chunk| {
-            for (h, p) in h.chunks_mut(chunk).zip(powers_of_tau.as_ref().chunks(chunk))
+            for (h, p) in h
+                .chunks_mut(chunk)
+                .zip(powers_of_tau.as_ref().chunks(chunk))
             {
                 let mut g1_wnaf = g1_wnaf.shared();
 
                 scope.spawn(move || {
                     // Set values of the H query to g1^{(tau^i * t(tau)) / delta}
-                    for (h, p) in h.iter_mut().zip(p.iter())
+                    for (h, p) in h.iter_mut().zip(p.iter()) {
-                    {
                         // Compute final exponent
                         let mut exp = p.0;
                         exp.mul_assign(&coeff);
@@ -325,9 +306,8 @@ pub fn generate_parameters<E, C>(
         beta: &E::Fr,
 
         // Worker
-        worker: &Worker
+        worker: &Worker,
-    )
+    ) {
-    {
         // Sanity check
         assert_eq!(a.len(), at.len());
         assert_eq!(a.len(), bt.len());
@@ -338,31 +318,32 @@ pub fn generate_parameters<E, C>(
 
         // Evaluate polynomials in multiple threads
         worker.scope(a.len(), |scope, chunk| {
-            for ((((((a, b_g1), b_g2), ext), at), bt), ct) in a.chunks_mut(chunk)
+            for ((((((a, b_g1), b_g2), ext), at), bt), ct) in a
-                                                               .zip(b_g1.chunks_mut(chunk))
+                .chunks_mut(chunk)
-                                                               .zip(b_g2.chunks_mut(chunk))
+                .zip(b_g1.chunks_mut(chunk))
-                                                               .zip(ext.chunks_mut(chunk))
+                .zip(b_g2.chunks_mut(chunk))
-                                                               .zip(at.chunks(chunk))
+                .zip(ext.chunks_mut(chunk))
-                                                               .zip(bt.chunks(chunk))
+                .zip(at.chunks(chunk))
-                                                               .zip(ct.chunks(chunk))
+                .zip(bt.chunks(chunk))
+                .zip(ct.chunks(chunk))
             {
                 let mut g1_wnaf = g1_wnaf.shared();
                 let mut g2_wnaf = g2_wnaf.shared();
 
                 scope.spawn(move || {
-                    for ((((((a, b_g1), b_g2), ext), at), bt), ct) in a.iter_mut()
+                    for ((((((a, b_g1), b_g2), ext), at), bt), ct) in a
-                                                                       .zip(b_g1.iter_mut())
+                        .iter_mut()
-                                                                       .zip(b_g2.iter_mut())
+                        .zip(b_g1.iter_mut())
-                                                                       .zip(ext.iter_mut())
+                        .zip(b_g2.iter_mut())
-                                                                       .zip(at.iter())
+                        .zip(ext.iter_mut())
-                                                                       .zip(bt.iter())
+                        .zip(at.iter())
-                                                                       .zip(ct.iter())
+                        .zip(bt.iter())
+                        .zip(ct.iter())
                     {
                         fn eval_at_tau<E: Engine>(
                             powers_of_tau: &[Scalar<E>],
-                            p: &[(E::Fr, usize)]
+                            p: &[(E::Fr, usize)],
-                        ) -> E::Fr
+                        ) -> E::Fr {
-                        {
                             let mut acc = E::Fr::zero();
 
                             for &(ref coeff, index) in p {
@@ -427,10 +408,10 @@ pub fn generate_parameters<E, C>(
         &gamma_inverse,
         &alpha,
         &beta,
-        &worker
+        &worker,
     );
 
-    // Evaluate for auxillary variables.
+    // Evaluate for auxiliary variables.
     eval(
         &g1_wnaf,
         &g2_wnaf,
@@ -445,7 +426,7 @@ pub fn generate_parameters<E, C>(
         &delta_inverse,
         &alpha,
         &beta,
-        &worker
+        &worker,
     );
 
     // Don't allow any elements be unconstrained, so that
@@ -466,7 +447,7 @@ pub fn generate_parameters<E, C>(
         gamma_g2: g2.mul(gamma).into_affine(),
         delta_g1: g1.mul(delta).into_affine(),
         delta_g2: g2.mul(delta).into_affine(),
-        ic: ic.into_iter().map(|e| e.into_affine()).collect()
+        ic: ic.into_iter().map(|e| e.into_affine()).collect(),
     };
 
     Ok(Parameters {
@@ -475,8 +456,23 @@ pub fn generate_parameters<E, C>(
         l: Arc::new(l.into_iter().map(|e| e.into_affine()).collect()),
 
         // Filter points at infinity away from A/B queries
-        a: Arc::new(a.into_iter().filter(|e| !e.is_zero()).map(|e| e.into_affine()).collect()),
+        a: Arc::new(
-        b_g1: Arc::new(b_g1.into_iter().filter(|e| !e.is_zero()).map(|e| e.into_affine()).collect()),
+            a.into_iter()
-        b_g2: Arc::new(b_g2.into_iter().filter(|e| !e.is_zero()).map(|e| e.into_affine()).collect())
+                .filter(|e| !e.is_zero())
+                .map(|e| e.into_affine())
+                .collect(),
+        ),
+        b_g1: Arc::new(
+            b_g1.into_iter()
+                .filter(|e| !e.is_zero())
+                .map(|e| e.into_affine())
+                .collect(),
+        ),
+        b_g2: Arc::new(
+            b_g2.into_iter()
+                .filter(|e| !e.is_zero())
+                .map(|e| e.into_affine())
+                .collect(),
+        ),
     })
 }

bellman/src/groth16/mod.rs

@@ -1,17 +1,12 @@
-use pairing::{
+use group::{CurveAffine, EncodedPoint};
-    Engine,
+use pairing::{Engine, PairingCurveAffine};
-    CurveAffine,
-    EncodedPoint
-};
 
-use ::{
+use SynthesisError;
-    SynthesisError
-};
 
+use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
 use multiexp::SourceBuilder;
 use std::io::{self, Read, Write};
 use std::sync::Arc;
-use byteorder::{BigEndian, WriteBytesExt, ReadBytesExt};
 
 #[cfg(test)]
 mod tests;
@@ -28,23 +23,17 @@ pub use self::verifier::*;
 pub struct Proof<E: Engine> {
     pub a: E::G1Affine,
     pub b: E::G2Affine,
-    pub c: E::G1Affine
+    pub c: E::G1Affine,
 }
 
 impl<E: Engine> PartialEq for Proof<E> {
     fn eq(&self, other: &Self) -> bool {
-        self.a == other.a &&
+        self.a == other.a && self.b == other.b && self.c == other.c
-        self.b == other.b &&
-        self.c == other.c
     }
 }
 
 impl<E: Engine> Proof<E> {
-    pub fn write<W: Write>(
+    pub fn write<W: Write>(&self, mut writer: W) -> io::Result<()> {
-        &self,
-        mut writer: W
-    ) -> io::Result<()>
-    {
         writer.write_all(self.a.into_compressed().as_ref())?;
         writer.write_all(self.b.into_compressed().as_ref())?;
         writer.write_all(self.c.into_compressed().as_ref())?;
@@ -52,48 +41,56 @@ impl<E: Engine> Proof<E> {
         Ok(())
     }
 
-    pub fn read<R: Read>(
+    pub fn read<R: Read>(mut reader: R) -> io::Result<Self> {
-        mut reader: R
-    ) -> io::Result<Self>
-    {
         let mut g1_repr = <E::G1Affine as CurveAffine>::Compressed::empty();
         let mut g2_repr = <E::G2Affine as CurveAffine>::Compressed::empty();
 
         reader.read_exact(g1_repr.as_mut())?;
         let a = g1_repr
-                .into_affine()
+            .into_affine()
-                .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
-                .and_then(|e| if e.is_zero() {
+            .and_then(|e| {
-                    Err(io::Error::new(io::ErrorKind::InvalidData, "point at infinity"))
+                if e.is_zero() {
+                    Err(io::Error::new(
+                        io::ErrorKind::InvalidData,
+                        "point at infinity",
+                    ))
                 } else {
                     Ok(e)
-                })?;
+                }
+            })?;
 
         reader.read_exact(g2_repr.as_mut())?;
         let b = g2_repr
-                .into_affine()
+            .into_affine()
-                .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
-                .and_then(|e| if e.is_zero() {
+            .and_then(|e| {
-                    Err(io::Error::new(io::ErrorKind::InvalidData, "point at infinity"))
+                if e.is_zero() {
+                    Err(io::Error::new(
+                        io::ErrorKind::InvalidData,
+                        "point at infinity",
+                    ))
                 } else {
                     Ok(e)
-                })?;
+                }
+            })?;
 
         reader.read_exact(g1_repr.as_mut())?;
         let c = g1_repr
-                .into_affine()
+            .into_affine()
-                .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
-                .and_then(|e| if e.is_zero() {
+            .and_then(|e| {
-                    Err(io::Error::new(io::ErrorKind::InvalidData, "point at infinity"))
+                if e.is_zero() {
+                    Err(io::Error::new(
+                        io::ErrorKind::InvalidData,
+                        "point at infinity",
+                    ))
                 } else {
                     Ok(e)
-                })?;
+                }
+            })?;
 
-        Ok(Proof {
+        Ok(Proof { a: a, b: b, c: c })
-            a: a,
-            b: b,
-            c: c
-        })
     }
 }
 
@@ -122,27 +119,23 @@ pub struct VerifyingKey<E: Engine> {
     // for all public inputs. Because all public inputs have a dummy constraint,
     // this is the same size as the number of inputs, and never contains points
     // at infinity.
-    pub ic: Vec<E::G1Affine>
+    pub ic: Vec<E::G1Affine>,
 }
 
 impl<E: Engine> PartialEq for VerifyingKey<E> {
     fn eq(&self, other: &Self) -> bool {
-        self.alpha_g1 == other.alpha_g1 &&
+        self.alpha_g1 == other.alpha_g1
-        self.beta_g1 == other.beta_g1 &&
+            && self.beta_g1 == other.beta_g1
-        self.beta_g2 == other.beta_g2 &&
+            && self.beta_g2 == other.beta_g2
-        self.gamma_g2 == other.gamma_g2 &&
+            && self.gamma_g2 == other.gamma_g2
-        self.delta_g1 == other.delta_g1 &&
+            && self.delta_g1 == other.delta_g1
-        self.delta_g2 == other.delta_g2 &&
+            && self.delta_g2 == other.delta_g2
-        self.ic == other.ic
+            && self.ic == other.ic
     }
 }
 
 impl<E: Engine> VerifyingKey<E> {
-    pub fn write<W: Write>(
+    pub fn write<W: Write>(&self, mut writer: W) -> io::Result<()> {
-        &self,
-        mut writer: W
-    ) -> io::Result<()>
-    {
         writer.write_all(self.alpha_g1.into_uncompressed().as_ref())?;
         writer.write_all(self.beta_g1.into_uncompressed().as_ref())?;
         writer.write_all(self.beta_g2.into_uncompressed().as_ref())?;
@@ -157,30 +150,39 @@ impl<E: Engine> VerifyingKey<E> {
         Ok(())
     }
 
-    pub fn read<R: Read>(
+    pub fn read<R: Read>(mut reader: R) -> io::Result<Self> {
-        mut reader: R
-    ) -> io::Result<Self>
-    {
         let mut g1_repr = <E::G1Affine as CurveAffine>::Uncompressed::empty();
         let mut g2_repr = <E::G2Affine as CurveAffine>::Uncompressed::empty();
 
         reader.read_exact(g1_repr.as_mut())?;
-        let alpha_g1 = g1_repr.into_affine().map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
+        let alpha_g1 = g1_repr
+            .into_affine()
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
 
         reader.read_exact(g1_repr.as_mut())?;
-        let beta_g1 = g1_repr.into_affine().map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
+        let beta_g1 = g1_repr
+            .into_affine()
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
 
         reader.read_exact(g2_repr.as_mut())?;
-        let beta_g2 = g2_repr.into_affine().map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
+        let beta_g2 = g2_repr
+            .into_affine()
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
 
         reader.read_exact(g2_repr.as_mut())?;
-        let gamma_g2 = g2_repr.into_affine().map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
+        let gamma_g2 = g2_repr
+            .into_affine()
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
 
         reader.read_exact(g1_repr.as_mut())?;
-        let delta_g1 = g1_repr.into_affine().map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
+        let delta_g1 = g1_repr
+            .into_affine()
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
 
         reader.read_exact(g2_repr.as_mut())?;
-        let delta_g2 = g2_repr.into_affine().map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
+        let delta_g2 = g2_repr
+            .into_affine()
+            .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))?;
 
         let ic_len = reader.read_u32::<BigEndian>()? as usize;
 
@@ -189,13 +191,18 @@ impl<E: Engine> VerifyingKey<E> {
         for _ in 0..ic_len {
             reader.read_exact(g1_repr.as_mut())?;
             let g1 = g1_repr
-                     .into_affine()
+                .into_affine()
-                     .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
+                .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
-                     .and_then(|e| if e.is_zero() {
+                .and_then(|e| {
-                         Err(io::Error::new(io::ErrorKind::InvalidData, "point at infinity"))
+                    if e.is_zero() {
-                     } else {
+                        Err(io::Error::new(
-                         Ok(e)
+                            io::ErrorKind::InvalidData,
-                     })?;
+                            "point at infinity",
+                        ))
+                    } else {
+                        Ok(e)
+                    }
+                })?;
 
             ic.push(g1);
         }
@@ -207,7 +214,7 @@ impl<E: Engine> VerifyingKey<E> {
             gamma_g2: gamma_g2,
             delta_g1: delta_g1,
             delta_g2: delta_g2,
-            ic: ic
+            ic: ic,
         })
     }
 }
@@ -216,12 +223,12 @@ impl<E: Engine> VerifyingKey<E> {
 pub struct Parameters<E: Engine> {
     pub vk: VerifyingKey<E>,
 
-    // Elements of the form ((tau^i * t(tau)) / delta) for i between 0 and 
+    // Elements of the form ((tau^i * t(tau)) / delta) for i between 0 and
     // m-2 inclusive. Never contains points at infinity.
     pub h: Arc<Vec<E::G1Affine>>,
 
     // Elements of the form (beta * u_i(tau) + alpha v_i(tau) + w_i(tau)) / delta
-    // for all auxillary inputs. Variables can never be unconstrained, so this
+    // for all auxiliary inputs. Variables can never be unconstrained, so this
     // never contains points at infinity.
     pub l: Arc<Vec<E::G1Affine>>,
 
@@ -234,26 +241,22 @@ pub struct Parameters<E: Engine> {
     // G1 and G2 for C/B queries, respectively. Never contains points at
     // infinity for the same reason as the "A" polynomials.
     pub b_g1: Arc<Vec<E::G1Affine>>,
-    pub b_g2: Arc<Vec<E::G2Affine>>
+    pub b_g2: Arc<Vec<E::G2Affine>>,
 }
 
 impl<E: Engine> PartialEq for Parameters<E> {
     fn eq(&self, other: &Self) -> bool {
-        self.vk == other.vk &&
+        self.vk == other.vk
-        self.h == other.h &&
+            && self.h == other.h
-        self.l == other.l &&
+            && self.l == other.l
-        self.a == other.a &&
+            && self.a == other.a
-        self.b_g1 == other.b_g1 &&
+            && self.b_g1 == other.b_g1
-        self.b_g2 == other.b_g2
+            && self.b_g2 == other.b_g2
     }
 }
 
 impl<E: Engine> Parameters<E> {
-    pub fn write<W: Write>(
+    pub fn write<W: Write>(&self, mut writer: W) -> io::Result<()> {
-        &self,
-        mut writer: W
-    ) -> io::Result<()>
-    {
         self.vk.write(&mut writer)?;
 
         writer.write_u32::<BigEndian>(self.h.len() as u32)?;
@@ -284,27 +287,26 @@ impl<E: Engine> Parameters<E> {
         Ok(())
     }
 
-    pub fn read<R: Read>(
+    pub fn read<R: Read>(mut reader: R, checked: bool) -> io::Result<Self> {
-        mut reader: R,
-        checked: bool
-    ) -> io::Result<Self>
-    {
         let read_g1 = |reader: &mut R| -> io::Result<E::G1Affine> {
             let mut repr = <E::G1Affine as CurveAffine>::Uncompressed::empty();
             reader.read_exact(repr.as_mut())?;
 
             if checked {
-                repr
+                repr.into_affine()
-                .into_affine()
             } else {
-                repr
+                repr.into_affine_unchecked()
-                .into_affine_unchecked()
             }
             .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
-            .and_then(|e| if e.is_zero() {
+            .and_then(|e| {
-                Err(io::Error::new(io::ErrorKind::InvalidData, "point at infinity"))
+                if e.is_zero() {
-            } else {
+                    Err(io::Error::new(
-                Ok(e)
+                        io::ErrorKind::InvalidData,
+                        "point at infinity",
+                    ))
+                } else {
+                    Ok(e)
+                }
             })
         };
 
@@ -313,17 +315,20 @@ impl<E: Engine> Parameters<E> {
             reader.read_exact(repr.as_mut())?;
 
             if checked {
-                repr
+                repr.into_affine()
-                .into_affine()
             } else {
-                repr
+                repr.into_affine_unchecked()
-                .into_affine_unchecked()
             }
             .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e))
-            .and_then(|e| if e.is_zero() {
+            .and_then(|e| {
-                Err(io::Error::new(io::ErrorKind::InvalidData, "point at infinity"))
+                if e.is_zero() {
-            } else {
+                    Err(io::Error::new(
-                Ok(e)
+                        io::ErrorKind::InvalidData,
+                        "point at infinity",
+                    ))
+                } else {
+                    Ok(e)
+                }
             })
         };
 
@@ -376,7 +381,7 @@ impl<E: Engine> Parameters<E> {
             l: Arc::new(l),
             a: Arc::new(a),
             b_g1: Arc::new(b_g1),
-            b_g2: Arc::new(b_g2)
+            b_g2: Arc::new(b_g2),
         })
     }
 }
@@ -385,43 +390,34 @@ pub struct PreparedVerifyingKey<E: Engine> {
     /// Pairing result of alpha*beta
     alpha_g1_beta_g2: E::Fqk,
     /// -gamma in G2
-    neg_gamma_g2: <E::G2Affine as CurveAffine>::Prepared,
+    neg_gamma_g2: <E::G2Affine as PairingCurveAffine>::Prepared,
     /// -delta in G2
-    neg_delta_g2: <E::G2Affine as CurveAffine>::Prepared,
+    neg_delta_g2: <E::G2Affine as PairingCurveAffine>::Prepared,
     /// Copy of IC from `VerifiyingKey`.
-    ic: Vec<E::G1Affine>
+    ic: Vec<E::G1Affine>,
 }
 
 pub trait ParameterSource<E: Engine> {
     type G1Builder: SourceBuilder<E::G1Affine>;
     type G2Builder: SourceBuilder<E::G2Affine>;
 
-    fn get_vk(
+    fn get_vk(&mut self, num_ic: usize) -> Result<VerifyingKey<E>, SynthesisError>;
-        &mut self,
+    fn get_h(&mut self, num_h: usize) -> Result<Self::G1Builder, SynthesisError>;
-        num_ic: usize
+    fn get_l(&mut self, num_l: usize) -> Result<Self::G1Builder, SynthesisError>;
-    ) -> Result<VerifyingKey<E>, SynthesisError>;
-    fn get_h(
-        &mut self,
-        num_h: usize
-    ) -> Result<Self::G1Builder, SynthesisError>;
-    fn get_l(
-        &mut self,
-        num_l: usize
-    ) -> Result<Self::G1Builder, SynthesisError>;
     fn get_a(
         &mut self,
         num_inputs: usize,
-        num_aux: usize
+        num_aux: usize,
     ) -> Result<(Self::G1Builder, Self::G1Builder), SynthesisError>;
     fn get_b_g1(
         &mut self,
         num_inputs: usize,
-        num_aux: usize
+        num_aux: usize,
     ) -> Result<(Self::G1Builder, Self::G1Builder), SynthesisError>;
     fn get_b_g2(
         &mut self,
         num_inputs: usize,
-        num_aux: usize
+        num_aux: usize,
     ) -> Result<(Self::G2Builder, Self::G2Builder), SynthesisError>;
 }
 
@@ -429,54 +425,39 @@ impl<'a, E: Engine> ParameterSource<E> for &'a Parameters<E> {
     type G1Builder = (Arc<Vec<E::G1Affine>>, usize);
     type G2Builder = (Arc<Vec<E::G2Affine>>, usize);
 
-    fn get_vk(
+    fn get_vk(&mut self, _: usize) -> Result<VerifyingKey<E>, SynthesisError> {
-        &mut self,
-        _: usize
-    ) -> Result<VerifyingKey<E>, SynthesisError>
-    {
         Ok(self.vk.clone())
     }
 
-    fn get_h(
+    fn get_h(&mut self, _: usize) -> Result<Self::G1Builder, SynthesisError> {
-        &mut self,
-        _: usize
-    ) -> Result<Self::G1Builder, SynthesisError>
-    {
         Ok((self.h.clone(), 0))
     }
 
-    fn get_l(
+    fn get_l(&mut self, _: usize) -> Result<Self::G1Builder, SynthesisError> {
-        &mut self,
-        _: usize
-    ) -> Result<Self::G1Builder, SynthesisError>
-    {
         Ok((self.l.clone(), 0))
     }
 
     fn get_a(
         &mut self,
         num_inputs: usize,
-        _: usize
+        _: usize,
-    ) -> Result<(Self::G1Builder, Self::G1Builder), SynthesisError>
+    ) -> Result<(Self::G1Builder, Self::G1Builder), SynthesisError> {
-    {
         Ok(((self.a.clone(), 0), (self.a.clone(), num_inputs)))
     }
 
     fn get_b_g1(
         &mut self,
         num_inputs: usize,
-        _: usize
+        _: usize,
-    ) -> Result<(Self::G1Builder, Self::G1Builder), SynthesisError>
+    ) -> Result<(Self::G1Builder, Self::G1Builder), SynthesisError> {
-    {
         Ok(((self.b_g1.clone(), 0), (self.b_g1.clone(), num_inputs)))
     }
 
     fn get_b_g2(
         &mut self,
         num_inputs: usize,
-        _: usize
+        _: usize,
-    ) -> Result<(Self::G2Builder, Self::G2Builder), SynthesisError>
+    ) -> Result<(Self::G2Builder, Self::G2Builder), SynthesisError> {
-    {
         Ok(((self.b_g2.clone(), 0), (self.b_g2.clone(), num_inputs)))
     }
 }
@@ -484,41 +465,38 @@ impl<'a, E: Engine> ParameterSource<E> for &'a Parameters<E> {
 #[cfg(test)]
 mod test_with_bls12_381 {
     use super::*;
-    use {Circuit, SynthesisError, ConstraintSystem};
+    use {Circuit, ConstraintSystem, SynthesisError};
 
-    use rand::{Rand, thread_rng};
+    use ff::Field;
-    use pairing::{Field};
     use pairing::bls12_381::{Bls12, Fr};
+    use rand::thread_rng;
 
     #[test]
     fn serialization() {
         struct MySillyCircuit<E: Engine> {
             a: Option<E::Fr>,
-            b: Option<E::Fr>
+            b: Option<E::Fr>,
         }
 
         impl<E: Engine> Circuit<E> for MySillyCircuit<E> {
             fn synthesize<CS: ConstraintSystem<E>>(
                 self,
-                cs: &mut CS
+                cs: &mut CS,
-            ) -> Result<(), SynthesisError>
+            ) -> Result<(), SynthesisError> {
-            {
                 let a = cs.alloc(|| "a", || self.a.ok_or(SynthesisError::AssignmentMissing))?;
                 let b = cs.alloc(|| "b", || self.b.ok_or(SynthesisError::AssignmentMissing))?;
-                let c = cs.alloc_input(|| "c", || {
+                let c = cs.alloc_input(
-                    let mut a = self.a.ok_or(SynthesisError::AssignmentMissing)?;
+                    || "c",
-                    let b = self.b.ok_or(SynthesisError::AssignmentMissing)?;
+                    || {
+                        let mut a = self.a.ok_or(SynthesisError::AssignmentMissing)?;
+                        let b = self.b.ok_or(SynthesisError::AssignmentMissing)?;
 
-                    a.mul_assign(&b);
+                        a.mul_assign(&b);
-                    Ok(a)
+                        Ok(a)
-                })?;
+                    },
+                )?;
 
-                cs.enforce(
+                cs.enforce(|| "a*b=c", |lc| lc + a, |lc| lc + b, |lc| lc + c);
-                    || "a*b=c",
-                    |lc| lc + a,
-                    |lc| lc + b,
-                    |lc| lc + c
-                );
 
                 Ok(())
             }
@@ -526,10 +504,9 @@ mod test_with_bls12_381 {
 
         let rng = &mut thread_rng();
 
-        let params = generate_random_parameters::<Bls12, _, _>(
+        let params =
-            MySillyCircuit { a: None, b: None },
+            generate_random_parameters::<Bls12, _, _>(MySillyCircuit { a: None, b: None }, rng)
-            rng
+                .unwrap();
-        ).unwrap();
 
         {
             let mut v = vec![];
@@ -547,19 +524,20 @@ mod test_with_bls12_381 {
         let pvk = prepare_verifying_key::<Bls12>(&params.vk);
 
         for _ in 0..100 {
-            let a = Fr::rand(rng);
+            let a = Fr::random(rng);
-            let b = Fr::rand(rng);
+            let b = Fr::random(rng);
             let mut c = a;
             c.mul_assign(&b);
 
             let proof = create_random_proof(
                 MySillyCircuit {
                     a: Some(a),
-                    b: Some(b)
+                    b: Some(b),
                 },
                 &params,
-                rng
+                rng,
-            ).unwrap();
+            )
+            .unwrap();
 
             let mut v = vec![];
             proof.write(&mut v).unwrap();

bellman/src/groth16/prover.rs

@@ -1,54 +1,30 @@
-use rand::Rng;
+use rand_core::RngCore;
 
 use std::sync::Arc;
 
 use futures::Future;
 
-use pairing::{
+use ff::{Field, PrimeField};
-    Engine,
+use group::{CurveAffine, CurveProjective};
-    PrimeField,
+use pairing::Engine;
-    Field,
-    CurveProjective,
-    CurveAffine
-};
 
-use super::{
+use super::{ParameterSource, Proof};
-    ParameterSource,
-    Proof
-};
 
-use ::{
+use {Circuit, ConstraintSystem, Index, LinearCombination, SynthesisError, Variable};
-    SynthesisError,
-    Circuit,
-    ConstraintSystem,
-    LinearCombination,
-    Variable,
-    Index
-};
 
-use ::domain::{
+use domain::{EvaluationDomain, Scalar};
-    EvaluationDomain,
-    Scalar
-};
 
-use ::multiexp::{
+use multiexp::{multiexp, DensityTracker, FullDensity};
-    DensityTracker,
-    FullDensity,
-    multiexp
-};
 
-use ::multicore::{
+use multicore::Worker;
-    Worker
-};
 
 fn eval<E: Engine>(
     lc: &LinearCombination<E>,
     mut input_density: Option<&mut DensityTracker>,
     mut aux_density: Option<&mut DensityTracker>,
     input_assignment: &[E::Fr],
-    aux_assignment: &[E::Fr]
+    aux_assignment: &[E::Fr],
-) -> E::Fr
+) -> E::Fr {
-{
     let mut acc = E::Fr::zero();
 
     for &(index, coeff) in lc.0.iter() {
@@ -60,7 +36,7 @@ fn eval<E: Engine>(
                 if let Some(ref mut v) = input_density {
                     v.inc(i);
                 }
-            },
+            }
             Variable(Index::Aux(i)) => {
                 tmp = aux_assignment[i];
                 if let Some(ref mut v) = aux_density {
@@ -70,10 +46,10 @@ fn eval<E: Engine>(
         }
 
         if coeff == E::Fr::one() {
-           acc.add_assign(&tmp);
+            acc.add_assign(&tmp);
         } else {
-           tmp.mul_assign(&coeff);
+            tmp.mul_assign(&coeff);
-           acc.add_assign(&tmp);
+            acc.add_assign(&tmp);
         }
     }
 
@@ -93,18 +69,17 @@ struct ProvingAssignment<E: Engine> {
 
     // Assignments of variables
     input_assignment: Vec<E::Fr>,
-    aux_assignment: Vec<E::Fr>
+    aux_assignment: Vec<E::Fr>,
 }
 
 impl<E: Engine> ConstraintSystem<E> for ProvingAssignment<E> {
     type Root = Self;
 
-    fn alloc<F, A, AR>(
+    fn alloc<F, A, AR>(&mut self, _: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        _: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         self.aux_assignment.push(f()?);
         self.a_aux_density.add_element();
@@ -113,12 +88,11 @@ impl<E: Engine> ConstraintSystem<E> for ProvingAssignment<E> {
         Ok(Variable(Index::Aux(self.aux_assignment.len() - 1)))
     }
 
-    fn alloc_input<F, A, AR>(
+    fn alloc_input<F, A, AR>(&mut self, _: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        _: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         self.input_assignment.push(f()?);
         self.b_input_density.add_element();
@@ -126,17 +100,13 @@ impl<E: Engine> ConstraintSystem<E> for ProvingAssignment<E> {
         Ok(Variable(Index::Input(self.input_assignment.len() - 1)))
     }
 
-    fn enforce<A, AR, LA, LB, LC>(
+    fn enforce<A, AR, LA, LB, LC>(&mut self, _: A, a: LA, b: LB, c: LC)
-        &mut self,
+    where
-        _: A,
+        A: FnOnce() -> AR,
-        a: LA,
+        AR: Into<String>,
-        b: LB,
+        LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        c: LC
+        LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-    )
+        LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        where A: FnOnce() -> AR, AR: Into<String>,
-              LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>
     {
         let a = a(LinearCombination::zero());
         let b = b(LinearCombination::zero());
@@ -150,14 +120,14 @@ impl<E: Engine> ConstraintSystem<E> for ProvingAssignment<E> {
             None,
             Some(&mut self.a_aux_density),
             &self.input_assignment,
-            &self.aux_assignment
+            &self.aux_assignment,
         )));
         self.b.push(Scalar(eval(
             &b,
             Some(&mut self.b_input_density),
             Some(&mut self.b_aux_density),
             &self.input_assignment,
-            &self.aux_assignment
+            &self.aux_assignment,
         )));
         self.c.push(Scalar(eval(
             &c,
@@ -168,18 +138,19 @@ impl<E: Engine> ConstraintSystem<E> for ProvingAssignment<E> {
             None,
             None,
             &self.input_assignment,
-            &self.aux_assignment
+            &self.aux_assignment,
         )));
     }
 
     fn push_namespace<NR, N>(&mut self, _: N)
-        where NR: Into<String>, N: FnOnce() -> NR
+    where
+        NR: Into<String>,
+        N: FnOnce() -> NR,
     {
         // Do nothing; we don't care about namespaces in this context.
     }
 
-    fn pop_namespace(&mut self)
+    fn pop_namespace(&mut self) {
-    {
         // Do nothing; we don't care about namespaces in this context.
     }
 
@@ -191,12 +162,15 @@ impl<E: Engine> ConstraintSystem<E> for ProvingAssignment<E> {
 pub fn create_random_proof<E, C, R, P: ParameterSource<E>>(
     circuit: C,
     params: P,
-    rng: &mut R
+    rng: &mut R,
 ) -> Result<Proof<E>, SynthesisError>
-    where E: Engine, C: Circuit<E>, R: Rng
+where
+    E: Engine,
+    C: Circuit<E>,
+    R: RngCore,
 {
-    let r = rng.gen();
+    let r = E::Fr::random(rng);
-    let s = rng.gen();
+    let s = E::Fr::random(rng);
 
     create_proof::<E, C, P>(circuit, params, r, s)
 }
@@ -205,9 +179,11 @@ pub fn create_proof<E, C, P: ParameterSource<E>>(
     circuit: C,
     mut params: P,
     r: E::Fr,
-    s: E::Fr
+    s: E::Fr,
 ) -> Result<Proof<E>, SynthesisError>
-    where E: Engine, C: Circuit<E>
+where
+    E: Engine,
+    C: Circuit<E>,
 {
     let mut prover = ProvingAssignment {
         a_aux_density: DensityTracker::new(),
@@ -217,7 +193,7 @@ pub fn create_proof<E, C, P: ParameterSource<E>>(
         b: vec![],
         c: vec![],
         input_assignment: vec![],
-        aux_assignment: vec![]
+        aux_assignment: vec![],
     };
 
     prover.alloc_input(|| "", || Ok(E::Fr::one()))?;
@@ -225,11 +201,7 @@ pub fn create_proof<E, C, P: ParameterSource<E>>(
     circuit.synthesize(&mut prover)?;
 
     for i in 0..prover.input_assignment.len() {
-        prover.enforce(|| "",
+        prover.enforce(|| "", |lc| lc + Variable(Index::Input(i)), |lc| lc, |lc| lc);
-            |lc| lc + Variable(Index::Input(i)),
-            |lc| lc,
-            |lc| lc,
-        );
     }
 
     let worker = Worker::new();
@@ -263,31 +235,76 @@ pub fn create_proof<E, C, P: ParameterSource<E>>(
     };
 
     // TODO: parallelize if it's even helpful
-    let input_assignment = Arc::new(prover.input_assignment.into_iter().map(|s| s.into_repr()).collect::<Vec<_>>());
+    let input_assignment = Arc::new(
-    let aux_assignment = Arc::new(prover.aux_assignment.into_iter().map(|s| s.into_repr()).collect::<Vec<_>>());
+        prover
+            .input_assignment
+            .into_iter()
+            .map(|s| s.into_repr())
+            .collect::<Vec<_>>(),
+    );
+    let aux_assignment = Arc::new(
+        prover
+            .aux_assignment
+            .into_iter()
+            .map(|s| s.into_repr())
+            .collect::<Vec<_>>(),
+    );
 
-    let l = multiexp(&worker, params.get_l(aux_assignment.len())?, FullDensity, aux_assignment.clone());
+    let l = multiexp(
+        &worker,
+        params.get_l(aux_assignment.len())?,
+        FullDensity,
+        aux_assignment.clone(),
+    );
 
     let a_aux_density_total = prover.a_aux_density.get_total_density();
 
-    let (a_inputs_source, a_aux_source) = params.get_a(input_assignment.len(), a_aux_density_total)?;
+    let (a_inputs_source, a_aux_source) =
+        params.get_a(input_assignment.len(), a_aux_density_total)?;
 
-    let a_inputs = multiexp(&worker, a_inputs_source, FullDensity, input_assignment.clone());
+    let a_inputs = multiexp(
-    let a_aux = multiexp(&worker, a_aux_source, Arc::new(prover.a_aux_density), aux_assignment.clone());
+        &worker,
+        a_inputs_source,
+        FullDensity,
+        input_assignment.clone(),
+    );
+    let a_aux = multiexp(
+        &worker,
+        a_aux_source,
+        Arc::new(prover.a_aux_density),
+        aux_assignment.clone(),
+    );
 
     let b_input_density = Arc::new(prover.b_input_density);
     let b_input_density_total = b_input_density.get_total_density();
     let b_aux_density = Arc::new(prover.b_aux_density);
     let b_aux_density_total = b_aux_density.get_total_density();
 
-    let (b_g1_inputs_source, b_g1_aux_source) = params.get_b_g1(b_input_density_total, b_aux_density_total)?;
+    let (b_g1_inputs_source, b_g1_aux_source) =
+        params.get_b_g1(b_input_density_total, b_aux_density_total)?;
 
-    let b_g1_inputs = multiexp(&worker, b_g1_inputs_source, b_input_density.clone(), input_assignment.clone());
+    let b_g1_inputs = multiexp(
-    let b_g1_aux = multiexp(&worker, b_g1_aux_source, b_aux_density.clone(), aux_assignment.clone());
+        &worker,
+        b_g1_inputs_source,
+        b_input_density.clone(),
+        input_assignment.clone(),
+    );
+    let b_g1_aux = multiexp(
+        &worker,
+        b_g1_aux_source,
+        b_aux_density.clone(),
+        aux_assignment.clone(),
+    );
 
-    let (b_g2_inputs_source, b_g2_aux_source) = params.get_b_g2(b_input_density_total, b_aux_density_total)?;
+    let (b_g2_inputs_source, b_g2_aux_source) =
-    
+        params.get_b_g2(b_input_density_total, b_aux_density_total)?;
-    let b_g2_inputs = multiexp(&worker, b_g2_inputs_source, b_input_density, input_assignment);
+
+    let b_g2_inputs = multiexp(
+        &worker,
+        b_g2_inputs_source,
+        b_input_density,
+        input_assignment,
+    );
     let b_g2_aux = multiexp(&worker, b_g2_aux_source, b_aux_density, aux_assignment);
 
     if vk.delta_g1.is_zero() || vk.delta_g2.is_zero() {
@@ -329,6 +346,6 @@ pub fn create_proof<E, C, P: ParameterSource<E>>(
     Ok(Proof {
         a: g_a.into_affine(),
         b: g_b.into_affine(),
-        c: g_c.into_affine()
+        c: g_c.into_affine(),
     })
 }

bellman/src/groth16/tests/dummy_engine.rs

@@ -1,20 +1,13 @@
-use pairing::{
+use ff::{
-    Engine,
+    Field, LegendreSymbol, PrimeField, PrimeFieldDecodingError, PrimeFieldRepr, ScalarEngine,
-    PrimeField,
-    PrimeFieldRepr,
-    Field,
     SqrtField,
-    LegendreSymbol,
-    CurveProjective,
-    CurveAffine,
-    PrimeFieldDecodingError,
-    GroupDecodingError,
-    EncodedPoint
 };
+use group::{CurveAffine, CurveProjective, EncodedPoint, GroupDecodingError};
+use pairing::{Engine, PairingCurveAffine};
 
+use rand_core::RngCore;
 use std::cmp::Ordering;
 use std::fmt;
-use rand::{Rand, Rng};
 use std::num::Wrapping;
 
 const MODULUS_R: Wrapping<u32> = Wrapping(64513);
@@ -28,13 +21,11 @@ impl fmt::Display for Fr {
     }
 }
 
-impl Rand for Fr {
-    fn rand<R: Rng>(rng: &mut R) -> Self {
-        Fr(Wrapping(rng.gen()) % MODULUS_R)
-    }
-}
-
 impl Field for Fr {
+    fn random<R: RngCore>(rng: &mut R) -> Self {
+        Fr(Wrapping(rng.next_u32()) % MODULUS_R)
+    }
+
     fn zero() -> Self {
         Fr(Wrapping(0))
     }
@@ -90,9 +81,13 @@ impl SqrtField for Fr {
     fn legendre(&self) -> LegendreSymbol {
         // s = self^((r - 1) // 2)
         let s = self.pow([32256]);
-        if s == <Fr as Field>::zero() { LegendreSymbol::Zero }
+        if s == <Fr as Field>::zero() {
-        else if s == <Fr as Field>::one() { LegendreSymbol::QuadraticResidue }
+            LegendreSymbol::Zero
-        else { LegendreSymbol::QuadraticNonResidue }
+        } else if s == <Fr as Field>::one() {
+            LegendreSymbol::QuadraticResidue
+        } else {
+            LegendreSymbol::QuadraticNonResidue
+        }
     }
 
     fn sqrt(&self) -> Option<Self> {
@@ -110,7 +105,7 @@ impl SqrtField for Fr {
                 let mut m = Fr::S;
 
                 while t != <Fr as Field>::one() {
-                let mut i = 1;
+                    let mut i = 1;
                     {
                         let mut t2i = t;
                         t2i.square();
@@ -153,12 +148,6 @@ impl PartialOrd for FrRepr {
     }
 }
 
-impl Rand for FrRepr {
-    fn rand<R: Rng>(rng: &mut R) -> Self {
-        FrRepr([rng.gen()])
-    }
-}
-
 impl fmt::Display for FrRepr {
     fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
         write!(f, "{}", (self.0)[0])
@@ -263,23 +252,29 @@ impl PrimeField for Fr {
 #[derive(Clone)]
 pub struct DummyEngine;
 
-impl Engine for DummyEngine {
+impl ScalarEngine for DummyEngine {
     type Fr = Fr;
+}
+
+impl Engine for DummyEngine {
     type G1 = Fr;
     type G1Affine = Fr;
     type G2 = Fr;
     type G2Affine = Fr;
     type Fq = Fr;
     type Fqe = Fr;
-    
+
     // TODO: This should be F_645131 or something. Doesn't matter for now.
     type Fqk = Fr;
 
     fn miller_loop<'a, I>(i: I) -> Self::Fqk
-        where I: IntoIterator<Item=&'a (
+    where
-                                    &'a <Self::G1Affine as CurveAffine>::Prepared,
+        I: IntoIterator<
-                                    &'a <Self::G2Affine as CurveAffine>::Prepared
+            Item = &'a (
-                               )>
+                &'a <Self::G1Affine as PairingCurveAffine>::Prepared,
+                &'a <Self::G2Affine as PairingCurveAffine>::Prepared,
+            ),
+        >,
     {
         let mut acc = <Fr as Field>::zero();
 
@@ -293,8 +288,7 @@ impl Engine for DummyEngine {
     }
 
     /// Perform final exponentiation of the result of a miller loop.
-    fn final_exponentiation(this: &Self::Fqk) -> Option<Self::Fqk>
+    fn final_exponentiation(this: &Self::Fqk) -> Option<Self::Fqk> {
-    {
         Some(*this)
     }
 }
@@ -305,6 +299,10 @@ impl CurveProjective for Fr {
     type Scalar = Fr;
     type Engine = DummyEngine;
 
+    fn random<R: RngCore>(rng: &mut R) -> Self {
+        <Fr as Field>::random(rng)
+    }
+
     fn zero() -> Self {
         <Fr as Field>::zero()
     }
@@ -317,9 +315,7 @@ impl CurveProjective for Fr {
         <Fr as Field>::is_zero(self)
     }
 
-    fn batch_normalization(_: &mut [Self]) {
+    fn batch_normalization(_: &mut [Self]) {}
-        
-    }
 
     fn is_normalized(&self) -> bool {
         true
@@ -341,8 +337,7 @@ impl CurveProjective for Fr {
         <Fr as Field>::negate(self);
     }
 
-    fn mul_assign<S: Into<<Self::Scalar as PrimeField>::Repr>>(&mut self, other: S)
+    fn mul_assign<S: Into<<Self::Scalar as PrimeField>::Repr>>(&mut self, other: S) {
-    {
         let tmp = Fr::from_repr(other.into()).unwrap();
 
         <Fr as Field>::mul_assign(self, &tmp);
@@ -401,11 +396,8 @@ impl EncodedPoint for FakePoint {
 }
 
 impl CurveAffine for Fr {
-    type Pair = Fr;
-    type PairingResult = Fr;
     type Compressed = FakePoint;
     type Uncompressed = FakePoint;
-    type Prepared = Fr;
     type Projective = Fr;
     type Base = Fr;
     type Scalar = Fr;
@@ -427,8 +419,7 @@ impl CurveAffine for Fr {
         <Fr as Field>::negate(self);
     }
 
-    fn mul<S: Into<<Self::Scalar as PrimeField>::Repr>>(&self, other: S) -> Self::Projective
+    fn mul<S: Into<<Self::Scalar as PrimeField>::Repr>>(&self, other: S) -> Self::Projective {
-    {
         let mut res = *self;
         let tmp = Fr::from_repr(other.into()).unwrap();
 
@@ -437,6 +428,16 @@ impl CurveAffine for Fr {
         res
     }
 
+    fn into_projective(&self) -> Self::Projective {
+        *self
+    }
+}
+
+impl PairingCurveAffine for Fr {
+    type Prepared = Fr;
+    type Pair = Fr;
+    type PairingResult = Fr;
+
     fn prepare(&self) -> Self::Prepared {
         *self
     }
@@ -444,8 +445,4 @@ impl CurveAffine for Fr {
     fn pairing_with(&self, other: &Self::Pair) -> Self::PairingResult {
         self.mul(*other)
     }
-
-    fn into_projective(&self) -> Self::Projective {
-        *self
-    }
 }

bellman/src/groth16/tests/mod.rs

@@ -1,94 +1,87 @@
-use pairing::{
+use ff::{Field, PrimeField};
-    Engine,
+use pairing::Engine;
-    Field,
-    PrimeField
-};
 
 mod dummy_engine;
 use self::dummy_engine::*;
 
 use std::marker::PhantomData;
 
-use ::{
+use {Circuit, ConstraintSystem, SynthesisError};
-    Circuit,
-    ConstraintSystem,
-    SynthesisError
-};
 
-use super::{
+use super::{create_proof, generate_parameters, prepare_verifying_key, verify_proof};
-    generate_parameters,
-    prepare_verifying_key,
-    create_proof,
-    verify_proof
-};
 
 struct XORDemo<E: Engine> {
     a: Option<bool>,
     b: Option<bool>,
-    _marker: PhantomData<E>
+    _marker: PhantomData<E>,
 }
 
 impl<E: Engine> Circuit<E> for XORDemo<E> {
-    fn synthesize<CS: ConstraintSystem<E>>(
+    fn synthesize<CS: ConstraintSystem<E>>(self, cs: &mut CS) -> Result<(), SynthesisError> {
-        self,
+        let a_var = cs.alloc(
-        cs: &mut CS
+            || "a",
-    ) -> Result<(), SynthesisError>
+            || {
-    {
+                if self.a.is_some() {
-        let a_var = cs.alloc(|| "a", || {
+                    if self.a.unwrap() {
-            if self.a.is_some() {
+                        Ok(E::Fr::one())
-                if self.a.unwrap() {
+                    } else {
-                    Ok(E::Fr::one())
+                        Ok(E::Fr::zero())
+                    }
                 } else {
-                    Ok(E::Fr::zero())
+                    Err(SynthesisError::AssignmentMissing)
                 }
-            } else {
+            },
-                Err(SynthesisError::AssignmentMissing)
+        )?;
-            }
-        })?;
 
         cs.enforce(
             || "a_boolean_constraint",
             |lc| lc + CS::one() - a_var,
             |lc| lc + a_var,
-            |lc| lc
+            |lc| lc,
         );
 
-        let b_var = cs.alloc(|| "b", || {
+        let b_var = cs.alloc(
-            if self.b.is_some() {
+            || "b",
-                if self.b.unwrap() {
+            || {
-                    Ok(E::Fr::one())
+                if self.b.is_some() {
+                    if self.b.unwrap() {
+                        Ok(E::Fr::one())
+                    } else {
+                        Ok(E::Fr::zero())
+                    }
                 } else {
-                    Ok(E::Fr::zero())
+                    Err(SynthesisError::AssignmentMissing)
                 }
-            } else {
+            },
-                Err(SynthesisError::AssignmentMissing)
+        )?;
-            }
-        })?;
 
         cs.enforce(
             || "b_boolean_constraint",
             |lc| lc + CS::one() - b_var,
             |lc| lc + b_var,
-            |lc| lc
+            |lc| lc,
         );
 
-        let c_var = cs.alloc_input(|| "c", || {
+        let c_var = cs.alloc_input(
-            if self.a.is_some() && self.b.is_some() {
+            || "c",
-                if self.a.unwrap() ^ self.b.unwrap() {
+            || {
-                    Ok(E::Fr::one())
+                if self.a.is_some() && self.b.is_some() {
+                    if self.a.unwrap() ^ self.b.unwrap() {
+                        Ok(E::Fr::one())
+                    } else {
+                        Ok(E::Fr::zero())
+                    }
                 } else {
-                    Ok(E::Fr::zero())
+                    Err(SynthesisError::AssignmentMissing)
                 }
-            } else {
+            },
-                Err(SynthesisError::AssignmentMissing)
+        )?;
-            }
-        })?;
 
         cs.enforce(
             || "c_xor_constraint",
             |lc| lc + a_var + a_var,
             |lc| lc + b_var,
-            |lc| lc + a_var + b_var - c_var
+            |lc| lc + a_var + b_var - c_var,
         );
 
         Ok(())
@@ -109,19 +102,10 @@ fn test_xordemo() {
         let c = XORDemo::<DummyEngine> {
             a: None,
             b: None,
-            _marker: PhantomData
+            _marker: PhantomData,
         };
 
-        generate_parameters(
+        generate_parameters(c, g1, g2, alpha, beta, gamma, delta, tau).unwrap()
-            c,
-            g1,
-            g2,
-            alpha,
-            beta,
-            gamma,
-            delta,
-            tau
-        ).unwrap()
     };
 
     // This will synthesize the constraint system:
@@ -229,32 +213,35 @@ fn test_xordemo() {
     59158
     */
 
-    let u_i = [59158, 48317, 21767, 10402].iter().map(|e| {
+    let u_i = [59158, 48317, 21767, 10402]
-        Fr::from_str(&format!("{}", e)).unwrap()
+        .iter()
-    }).collect::<Vec<Fr>>();
+        .map(|e| Fr::from_str(&format!("{}", e)).unwrap())
-    let v_i = [0, 0, 60619, 30791].iter().map(|e| {
+        .collect::<Vec<Fr>>();
-        Fr::from_str(&format!("{}", e)).unwrap()
+    let v_i = [0, 0, 60619, 30791]
-    }).collect::<Vec<Fr>>();
+        .iter()
-    let w_i = [0, 23320, 41193, 41193].iter().map(|e| {
+        .map(|e| Fr::from_str(&format!("{}", e)).unwrap())
-        Fr::from_str(&format!("{}", e)).unwrap()
+        .collect::<Vec<Fr>>();
-    }).collect::<Vec<Fr>>();
+    let w_i = [0, 23320, 41193, 41193]
+        .iter()
+        .map(|e| Fr::from_str(&format!("{}", e)).unwrap())
+        .collect::<Vec<Fr>>();
 
-    for (u, a) in u_i.iter()
+    for (u, a) in u_i.iter().zip(&params.a[..]) {
-                     .zip(&params.a[..])
-    {
         assert_eq!(u, a);
     }
 
-    for (v, b) in v_i.iter()
+    for (v, b) in v_i
-                     .filter(|&&e| e != Fr::zero())
+        .iter()
-                     .zip(&params.b_g1[..])
+        .filter(|&&e| e != Fr::zero())
+        .zip(&params.b_g1[..])
     {
         assert_eq!(v, b);
     }
 
-    for (v, b) in v_i.iter()
+    for (v, b) in v_i
-                     .filter(|&&e| e != Fr::zero())
+        .iter()
-                     .zip(&params.b_g2[..])
+        .filter(|&&e| e != Fr::zero())
+        .zip(&params.b_g2[..])
     {
         assert_eq!(v, b);
     }
@@ -299,15 +286,10 @@ fn test_xordemo() {
         let c = XORDemo {
             a: Some(true),
             b: Some(false),
-            _marker: PhantomData
+            _marker: PhantomData,
         };
 
-        create_proof(
+        create_proof(c, &params, r, s).unwrap()
-            c,
-            &params,
-            r,
-            s
-        ).unwrap()
     };
 
     // A(x) =
@@ -323,7 +305,7 @@ fn test_xordemo() {
         expected_a.add_assign(&u_i[0]); // a_0 = 1
         expected_a.add_assign(&u_i[1]); // a_1 = 1
         expected_a.add_assign(&u_i[2]); // a_2 = 1
-        // a_3 = 0
+                                        // a_3 = 0
         assert_eq!(proof.a, expected_a);
     }
 
@@ -340,7 +322,7 @@ fn test_xordemo() {
         expected_b.add_assign(&v_i[0]); // a_0 = 1
         expected_b.add_assign(&v_i[1]); // a_1 = 1
         expected_b.add_assign(&v_i[2]); // a_2 = 1
-        // a_3 = 0
+                                        // a_3 = 0
         assert_eq!(proof.b, expected_b);
     }
 
@@ -381,7 +363,10 @@ fn test_xordemo() {
         expected_c.add_assign(&params.l[0]);
 
         // H query answer
-        for (i, coeff) in [5040, 11763, 10755, 63633, 128, 9747, 8739].iter().enumerate() {
+        for (i, coeff) in [5040, 11763, 10755, 63633, 128, 9747, 8739]
+            .iter()
+            .enumerate()
+        {
             let coeff = Fr::from_str(&format!("{}", coeff)).unwrap();
 
             let mut tmp = params.h[i];
@@ -392,9 +377,5 @@ fn test_xordemo() {
         assert_eq!(expected_c, proof.c);
     }
 
-    assert!(verify_proof(
+    assert!(verify_proof(&pvk, &proof, &[Fr::one()]).unwrap());
-        &pvk,
-        &proof,
-        &[Fr::one()]
-    ).unwrap());
 }

bellman/src/groth16/verifier.rs

@@ -1,24 +1,12 @@
-use pairing::{
+use ff::PrimeField;
-    Engine,
+use group::{CurveAffine, CurveProjective};
-    CurveProjective,
+use pairing::{Engine, PairingCurveAffine};
-    CurveAffine,
-    PrimeField
-};
 
-use super::{
+use super::{PreparedVerifyingKey, Proof, VerifyingKey};
-    Proof,
-    VerifyingKey,
-    PreparedVerifyingKey
-};
 
-use ::{
+use SynthesisError;
-    SynthesisError
-};
 
-pub fn prepare_verifying_key<E: Engine>(
+pub fn prepare_verifying_key<E: Engine>(vk: &VerifyingKey<E>) -> PreparedVerifyingKey<E> {
-    vk: &VerifyingKey<E>
-) -> PreparedVerifyingKey<E>
-{
     let mut gamma = vk.gamma_g2;
     gamma.negate();
     let mut delta = vk.delta_g2;
@@ -28,16 +16,15 @@ pub fn prepare_verifying_key<E: Engine>(
         alpha_g1_beta_g2: E::pairing(vk.alpha_g1, vk.beta_g2),
         neg_gamma_g2: gamma.prepare(),
         neg_delta_g2: delta.prepare(),
-        ic: vk.ic.clone()
+        ic: vk.ic.clone(),
     }
 }
 
 pub fn verify_proof<'a, E: Engine>(
     pvk: &'a PreparedVerifyingKey<E>,
     proof: &Proof<E>,
-    public_inputs: &[E::Fr]
+    public_inputs: &[E::Fr],
-) -> Result<bool, SynthesisError>
+) -> Result<bool, SynthesisError> {
-{
     if (public_inputs.len() + 1) != pvk.ic.len() {
         return Err(SynthesisError::MalformedVerifyingKey);
     }
@@ -56,11 +43,14 @@ pub fn verify_proof<'a, E: Engine>(
     // A * B + inputs * (-gamma) + C * (-delta) = alpha * beta
     // which allows us to do a single final exponentiation.
 
-    Ok(E::final_exponentiation(
+    Ok(E::final_exponentiation(&E::miller_loop(
-        &E::miller_loop([
+        [
             (&proof.a.prepare(), &proof.b.prepare()),
             (&acc.into_affine().prepare(), &pvk.neg_gamma_g2),
-            (&proof.c.prepare(), &pvk.neg_delta_g2)
+            (&proof.c.prepare(), &pvk.neg_delta_g2),
-        ].into_iter())
+        ]
-    ).unwrap() == pvk.alpha_g1_beta_g2)
+        .into_iter(),
+    ))
+    .unwrap()
+        == pvk.alpha_g1_beta_g2)
 }

bellman/src/lib.rs

@@ -1,35 +1,56 @@
+extern crate ff;
+extern crate group;
+#[cfg(feature = "pairing")]
 extern crate pairing;
-extern crate rand;
+extern crate rand_core;
-extern crate num_cpus;
-extern crate futures;
-extern crate futures_cpupool;
-extern crate bit_vec;
-extern crate crossbeam;
-extern crate byteorder;
 
+extern crate bit_vec;
+extern crate blake2s_simd;
+extern crate byteorder;
+extern crate futures;
+
+#[cfg(feature = "multicore")]
+extern crate crossbeam;
+#[cfg(feature = "multicore")]
+extern crate futures_cpupool;
+#[cfg(feature = "multicore")]
+extern crate num_cpus;
+
+#[cfg(test)]
+#[macro_use]
+extern crate hex_literal;
+
+#[cfg(test)]
+extern crate rand;
+
+#[cfg(test)]
+extern crate rand_xorshift;
+
+#[cfg(test)]
+extern crate sha2;
+
+pub mod domain;
+pub mod gadgets;
+#[cfg(feature = "groth16")]
+pub mod groth16;
 pub mod multicore;
 mod multiexp;
-pub mod domain;
-pub mod groth16;
 
-use pairing::{Engine, Field};
+use ff::{Field, ScalarEngine};
 
-use std::ops::{Add, Sub};
-use std::fmt;
 use std::error::Error;
+use std::fmt;
 use std::io;
 use std::marker::PhantomData;
+use std::ops::{Add, Sub};
 
 /// Computations are expressed in terms of arithmetic circuits, in particular
 /// rank-1 quadratic constraint systems. The `Circuit` trait represents a
 /// circuit that can be synthesized. The `synthesize` method is called during
 /// CRS generation and during proving.
-pub trait Circuit<E: Engine> {
+pub trait Circuit<E: ScalarEngine> {
     /// Synthesize the circuit into a rank-1 quadratic constraint system
-    fn synthesize<CS: ConstraintSystem<E>>(
+    fn synthesize<CS: ConstraintSystem<E>>(self, cs: &mut CS) -> Result<(), SynthesisError>;
-        self,
-        cs: &mut CS
-    ) -> Result<(), SynthesisError>;
 }
 
 /// Represents a variable in our constraint system.
@@ -51,31 +72,31 @@ impl Variable {
 }
 
 /// Represents the index of either an input variable or
-/// auxillary variable.
+/// auxiliary variable.
 #[derive(Copy, Clone, PartialEq, Debug)]
 pub enum Index {
     Input(usize),
-    Aux(usize)
+    Aux(usize),
 }
 
 /// This represents a linear combination of some variables, with coefficients
 /// in the scalar field of a pairing-friendly elliptic curve group.
 #[derive(Clone)]
-pub struct LinearCombination<E: Engine>(Vec<(Variable, E::Fr)>);
+pub struct LinearCombination<E: ScalarEngine>(Vec<(Variable, E::Fr)>);
 
-impl<E: Engine> AsRef<[(Variable, E::Fr)]> for LinearCombination<E> {
+impl<E: ScalarEngine> AsRef<[(Variable, E::Fr)]> for LinearCombination<E> {
     fn as_ref(&self) -> &[(Variable, E::Fr)] {
         &self.0
     }
 }
 
-impl<E: Engine> LinearCombination<E> {
+impl<E: ScalarEngine> LinearCombination<E> {
     pub fn zero() -> LinearCombination<E> {
         LinearCombination(vec![])
     }
 }
 
-impl<E: Engine> Add<(E::Fr, Variable)> for LinearCombination<E> {
+impl<E: ScalarEngine> Add<(E::Fr, Variable)> for LinearCombination<E> {
     type Output = LinearCombination<E>;
 
     fn add(mut self, (coeff, var): (E::Fr, Variable)) -> LinearCombination<E> {
@@ -85,7 +106,7 @@ impl<E: Engine> Add<(E::Fr, Variable)> for LinearCombination<E> {
     }
 }
 
-impl<E: Engine> Sub<(E::Fr, Variable)> for LinearCombination<E> {
+impl<E: ScalarEngine> Sub<(E::Fr, Variable)> for LinearCombination<E> {
     type Output = LinearCombination<E>;
 
     fn sub(self, (mut coeff, var): (E::Fr, Variable)) -> LinearCombination<E> {
@@ -95,7 +116,7 @@ impl<E: Engine> Sub<(E::Fr, Variable)> for LinearCombination<E> {
     }
 }
 
-impl<E: Engine> Add<Variable> for LinearCombination<E> {
+impl<E: ScalarEngine> Add<Variable> for LinearCombination<E> {
     type Output = LinearCombination<E>;
 
     fn add(self, other: Variable) -> LinearCombination<E> {
@@ -103,7 +124,7 @@ impl<E: Engine> Add<Variable> for LinearCombination<E> {
     }
 }
 
-impl<E: Engine> Sub<Variable> for LinearCombination<E> {
+impl<E: ScalarEngine> Sub<Variable> for LinearCombination<E> {
     type Output = LinearCombination<E>;
 
     fn sub(self, other: Variable) -> LinearCombination<E> {
@@ -111,7 +132,7 @@ impl<E: Engine> Sub<Variable> for LinearCombination<E> {
     }
 }
 
-impl<'a, E: Engine> Add<&'a LinearCombination<E>> for LinearCombination<E> {
+impl<'a, E: ScalarEngine> Add<&'a LinearCombination<E>> for LinearCombination<E> {
     type Output = LinearCombination<E>;
 
     fn add(mut self, other: &'a LinearCombination<E>) -> LinearCombination<E> {
@@ -123,7 +144,7 @@ impl<'a, E: Engine> Add<&'a LinearCombination<E>> for LinearCombination<E> {
     }
 }
 
-impl<'a, E: Engine> Sub<&'a LinearCombination<E>> for LinearCombination<E> {
+impl<'a, E: ScalarEngine> Sub<&'a LinearCombination<E>> for LinearCombination<E> {
     type Output = LinearCombination<E>;
 
     fn sub(mut self, other: &'a LinearCombination<E>) -> LinearCombination<E> {
@@ -135,7 +156,7 @@ impl<'a, E: Engine> Sub<&'a LinearCombination<E>> for LinearCombination<E> {
     }
 }
 
-impl<'a, E: Engine> Add<(E::Fr, &'a LinearCombination<E>)> for LinearCombination<E> {
+impl<'a, E: ScalarEngine> Add<(E::Fr, &'a LinearCombination<E>)> for LinearCombination<E> {
     type Output = LinearCombination<E>;
 
     fn add(mut self, (coeff, other): (E::Fr, &'a LinearCombination<E>)) -> LinearCombination<E> {
@@ -149,7 +170,7 @@ impl<'a, E: Engine> Add<(E::Fr, &'a LinearCombination<E>)> for LinearCombination
     }
 }
 
-impl<'a, E: Engine> Sub<(E::Fr, &'a LinearCombination<E>)> for LinearCombination<E> {
+impl<'a, E: ScalarEngine> Sub<(E::Fr, &'a LinearCombination<E>)> for LinearCombination<E> {
     type Output = LinearCombination<E>;
 
     fn sub(mut self, (coeff, other): (E::Fr, &'a LinearCombination<E>)) -> LinearCombination<E> {
@@ -181,8 +202,8 @@ pub enum SynthesisError {
     IoError(io::Error),
     /// During verification, our verifying key was malformed.
     MalformedVerifyingKey,
-    /// During CRS generation, we observed an unconstrained auxillary variable
+    /// During CRS generation, we observed an unconstrained auxiliary variable
-    UnconstrainedVariable
+    UnconstrainedVariable,
 }
 
 impl From<io::Error> for SynthesisError {
@@ -194,14 +215,16 @@ impl From<io::Error> for SynthesisError {
 impl Error for SynthesisError {
     fn description(&self) -> &str {
         match *self {
-            SynthesisError::AssignmentMissing => "an assignment for a variable could not be computed",
+            SynthesisError::AssignmentMissing => {
+                "an assignment for a variable could not be computed"
+            }
             SynthesisError::DivisionByZero => "division by zero",
             SynthesisError::Unsatisfiable => "unsatisfiable constraint system",
             SynthesisError::PolynomialDegreeTooLarge => "polynomial degree is too large",
             SynthesisError::UnexpectedIdentity => "encountered an identity element in the CRS",
             SynthesisError::IoError(_) => "encountered an I/O error",
             SynthesisError::MalformedVerifyingKey => "malformed verifying key",
-            SynthesisError::UnconstrainedVariable => "auxillary variable was unconstrained"
+            SynthesisError::UnconstrainedVariable => "auxiliary variable was unconstrained",
         }
     }
 }
@@ -219,7 +242,7 @@ impl fmt::Display for SynthesisError {
 
 /// Represents a constraint system which can have new variables
 /// allocated and constrains between them formed.
-pub trait ConstraintSystem<E: Engine>: Sized {
+pub trait ConstraintSystem<E: ScalarEngine>: Sized {
     /// Represents the type of the "root" of this constraint system
     /// so that nested namespaces can minimize indirection.
     type Root: ConstraintSystem<E>;
@@ -233,40 +256,36 @@ pub trait ConstraintSystem<E: Engine>: Sized {
     /// determine the assignment of the variable. The given `annotation` function is invoked
     /// in testing contexts in order to derive a unique name for this variable in the current
     /// namespace.
-    fn alloc<F, A, AR>(
+    fn alloc<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>;
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>;
 
     /// Allocate a public variable in the constraint system. The provided function is used to
     /// determine the assignment of the variable.
-    fn alloc_input<F, A, AR>(
+    fn alloc_input<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>;
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>;
 
     /// Enforce that `A` * `B` = `C`. The `annotation` function is invoked in testing contexts
     /// in order to derive a unique name for the constraint in the current namespace.
-    fn enforce<A, AR, LA, LB, LC>(
+    fn enforce<A, AR, LA, LB, LC>(&mut self, annotation: A, a: LA, b: LB, c: LC)
-        &mut self,
+    where
-        annotation: A,
+        A: FnOnce() -> AR,
-        a: LA,
+        AR: Into<String>,
-        b: LB,
+        LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        c: LC
+        LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-    )
+        LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>;
-        where A: FnOnce() -> AR, AR: Into<String>,
-              LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>;
 
     /// Create a new (sub)namespace and enter into it. Not intended
     /// for downstream use; use `namespace` instead.
     fn push_namespace<NR, N>(&mut self, name_fn: N)
-        where NR: Into<String>, N: FnOnce() -> NR;
+    where
+        NR: Into<String>,
+        N: FnOnce() -> NR;
 
     /// Exit out of the existing namespace. Not intended for
     /// downstream use; use `namespace` instead.
@@ -277,11 +296,10 @@ pub trait ConstraintSystem<E: Engine>: Sized {
     fn get_root(&mut self) -> &mut Self::Root;
 
     /// Begin a namespace for this constraint system.
-    fn namespace<'a, NR, N>(
+    fn namespace<'a, NR, N>(&'a mut self, name_fn: N) -> Namespace<'a, E, Self::Root>
-        &'a mut self,
+    where
-        name_fn: N
+        NR: Into<String>,
-    ) -> Namespace<'a, E, Self::Root>
+        N: FnOnce() -> NR,
-        where NR: Into<String>, N: FnOnce() -> NR
     {
         self.get_root().push_namespace(name_fn);
 
@@ -291,46 +309,40 @@ pub trait ConstraintSystem<E: Engine>: Sized {
 
 /// This is a "namespaced" constraint system which borrows a constraint system (pushing
 /// a namespace context) and, when dropped, pops out of the namespace context.
-pub struct Namespace<'a, E: Engine, CS: ConstraintSystem<E> + 'a>(&'a mut CS, PhantomData<E>);
+pub struct Namespace<'a, E: ScalarEngine, CS: ConstraintSystem<E> + 'a>(&'a mut CS, PhantomData<E>);
 
-impl<'cs, E: Engine, CS: ConstraintSystem<E>> ConstraintSystem<E> for Namespace<'cs, E, CS> {
+impl<'cs, E: ScalarEngine, CS: ConstraintSystem<E>> ConstraintSystem<E> for Namespace<'cs, E, CS> {
     type Root = CS::Root;
 
     fn one() -> Variable {
         CS::one()
     }
 
-    fn alloc<F, A, AR>(
+    fn alloc<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         self.0.alloc(annotation, f)
     }
 
-    fn alloc_input<F, A, AR>(
+    fn alloc_input<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         self.0.alloc_input(annotation, f)
     }
 
-    fn enforce<A, AR, LA, LB, LC>(
+    fn enforce<A, AR, LA, LB, LC>(&mut self, annotation: A, a: LA, b: LB, c: LC)
-        &mut self,
+    where
-        annotation: A,
+        A: FnOnce() -> AR,
-        a: LA,
+        AR: Into<String>,
-        b: LB,
+        LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        c: LC
+        LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-    )
+        LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        where A: FnOnce() -> AR, AR: Into<String>,
-              LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>
     {
         self.0.enforce(annotation, a, b, c)
     }
@@ -340,23 +352,23 @@ impl<'cs, E: Engine, CS: ConstraintSystem<E>> ConstraintSystem<E> for Namespace<
     // never a root constraint system.
 
     fn push_namespace<NR, N>(&mut self, _: N)
-        where NR: Into<String>, N: FnOnce() -> NR
+    where
+        NR: Into<String>,
+        N: FnOnce() -> NR,
     {
         panic!("only the root's push_namespace should be called");
     }
 
-    fn pop_namespace(&mut self)
+    fn pop_namespace(&mut self) {
-    {
         panic!("only the root's pop_namespace should be called");
     }
 
-    fn get_root(&mut self) -> &mut Self::Root
+    fn get_root(&mut self) -> &mut Self::Root {
-    {
         self.0.get_root()
     }
 }
 
-impl<'a, E: Engine, CS: ConstraintSystem<E>> Drop for Namespace<'a, E, CS> {
+impl<'a, E: ScalarEngine, CS: ConstraintSystem<E>> Drop for Namespace<'a, E, CS> {
     fn drop(&mut self) {
         self.get_root().pop_namespace()
     }
@@ -364,61 +376,55 @@ impl<'a, E: Engine, CS: ConstraintSystem<E>> Drop for Namespace<'a, E, CS> {
 
 /// Convenience implementation of ConstraintSystem<E> for mutable references to
 /// constraint systems.
-impl<'cs, E: Engine, CS: ConstraintSystem<E>> ConstraintSystem<E> for &'cs mut CS {
+impl<'cs, E: ScalarEngine, CS: ConstraintSystem<E>> ConstraintSystem<E> for &'cs mut CS {
     type Root = CS::Root;
 
     fn one() -> Variable {
         CS::one()
     }
 
-    fn alloc<F, A, AR>(
+    fn alloc<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         (**self).alloc(annotation, f)
     }
 
-    fn alloc_input<F, A, AR>(
+    fn alloc_input<F, A, AR>(&mut self, annotation: A, f: F) -> Result<Variable, SynthesisError>
-        &mut self,
+    where
-        annotation: A,
+        F: FnOnce() -> Result<E::Fr, SynthesisError>,
-        f: F
+        A: FnOnce() -> AR,
-    ) -> Result<Variable, SynthesisError>
+        AR: Into<String>,
-        where F: FnOnce() -> Result<E::Fr, SynthesisError>, A: FnOnce() -> AR, AR: Into<String>
     {
         (**self).alloc_input(annotation, f)
     }
 
-    fn enforce<A, AR, LA, LB, LC>(
+    fn enforce<A, AR, LA, LB, LC>(&mut self, annotation: A, a: LA, b: LB, c: LC)
-        &mut self,
+    where
-        annotation: A,
+        A: FnOnce() -> AR,
-        a: LA,
+        AR: Into<String>,
-        b: LB,
+        LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        c: LC
+        LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-    )
+        LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-        where A: FnOnce() -> AR, AR: Into<String>,
-              LA: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LB: FnOnce(LinearCombination<E>) -> LinearCombination<E>,
-              LC: FnOnce(LinearCombination<E>) -> LinearCombination<E>
     {
         (**self).enforce(annotation, a, b, c)
     }
 
     fn push_namespace<NR, N>(&mut self, name_fn: N)
-        where NR: Into<String>, N: FnOnce() -> NR
+    where
+        NR: Into<String>,
+        N: FnOnce() -> NR,
     {
         (**self).push_namespace(name_fn)
     }
 
-    fn pop_namespace(&mut self)
+    fn pop_namespace(&mut self) {
-    {
         (**self).pop_namespace()
     }
 
-    fn get_root(&mut self) -> &mut Self::Root
+    fn get_root(&mut self) -> &mut Self::Root {
-    {
         (**self).get_root()
     }
 }

bellman/src/multicore.rs

@@ -4,103 +4,158 @@
 //! crossbeam but may be extended in the future to
 //! allow for various parallelism strategies.
 
-use num_cpus;
+#[cfg(feature = "multicore")]
-use futures::{Future, IntoFuture, Poll};
+mod implementation {
-use futures_cpupool::{CpuPool, CpuFuture};
+    use crossbeam::{self, Scope};
-use crossbeam::{self, Scope};
+    use futures::{Future, IntoFuture, Poll};
+    use futures_cpupool::{CpuFuture, CpuPool};
+    use num_cpus;
 
-#[derive(Clone)]
+    #[derive(Clone)]
-pub struct Worker {
+    pub struct Worker {
-    cpus: usize,
+        cpus: usize,
-    pool: CpuPool
+        pool: CpuPool,
-}
+    }
 
-impl Worker {
+    impl Worker {
-    // We don't expose this outside the library so that
+        // We don't expose this outside the library so that
-    // all `Worker` instances have the same number of
+        // all `Worker` instances have the same number of
-    // CPUs configured.
+        // CPUs configured.
-    pub(crate) fn new_with_cpus(cpus: usize) -> Worker {
+        pub(crate) fn new_with_cpus(cpus: usize) -> Worker {
-        Worker {
+            Worker {
-            cpus: cpus,
+                cpus: cpus,
-            pool: CpuPool::new(cpus)
+                pool: CpuPool::new(cpus),
+            }
+        }
+
+        pub fn new() -> Worker {
+            Self::new_with_cpus(num_cpus::get())
+        }
+
+        pub fn log_num_cpus(&self) -> u32 {
+            log2_floor(self.cpus)
+        }
+
+        pub fn compute<F, R>(&self, f: F) -> WorkerFuture<R::Item, R::Error>
+        where
+            F: FnOnce() -> R + Send + 'static,
+            R: IntoFuture + 'static,
+            R::Future: Send + 'static,
+            R::Item: Send + 'static,
+            R::Error: Send + 'static,
+        {
+            WorkerFuture {
+                future: self.pool.spawn_fn(f),
+            }
+        }
+
+        pub fn scope<'a, F, R>(&self, elements: usize, f: F) -> R
+        where
+            F: FnOnce(&Scope<'a>, usize) -> R,
+        {
+            let chunk_size = if elements < self.cpus {
+                1
+            } else {
+                elements / self.cpus
+            };
+
+            crossbeam::scope(|scope| f(scope, chunk_size))
         }
     }
 
-    pub fn new() -> Worker {
+    pub struct WorkerFuture<T, E> {
-        Self::new_with_cpus(num_cpus::get())
+        future: CpuFuture<T, E>,
     }
 
-    pub fn log_num_cpus(&self) -> u32 {
+    impl<T: Send + 'static, E: Send + 'static> Future for WorkerFuture<T, E> {
-        log2_floor(self.cpus)
+        type Item = T;
-    }
+        type Error = E;
 
-    pub fn compute<F, R>(
+        fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
-        &self, f: F
+            self.future.poll()
-    ) -> WorkerFuture<R::Item, R::Error>
-        where F: FnOnce() -> R + Send + 'static,
-              R: IntoFuture + 'static,
-              R::Future: Send + 'static,
-              R::Item: Send + 'static,
-              R::Error: Send + 'static
-    {
-        WorkerFuture {
-            future: self.pool.spawn_fn(f)
         }
     }
 
-    pub fn scope<'a, F, R>(
+    fn log2_floor(num: usize) -> u32 {
-        &self,
+        assert!(num > 0);
-        elements: usize,
-        f: F
-    ) -> R
-        where F: FnOnce(&Scope<'a>, usize) -> R
-    {
-        let chunk_size = if elements < self.cpus {
-            1
-        } else {
-            elements / self.cpus
-        };
 
-        crossbeam::scope(|scope| {
+        let mut pow = 0;
-            f(scope, chunk_size)
+
-        })
+        while (1 << (pow + 1)) <= num {
+            pow += 1;
+        }
+
+        pow
+    }
+
+    #[test]
+    fn test_log2_floor() {
+        assert_eq!(log2_floor(1), 0);
+        assert_eq!(log2_floor(2), 1);
+        assert_eq!(log2_floor(3), 1);
+        assert_eq!(log2_floor(4), 2);
+        assert_eq!(log2_floor(5), 2);
+        assert_eq!(log2_floor(6), 2);
+        assert_eq!(log2_floor(7), 2);
+        assert_eq!(log2_floor(8), 3);
     }
 }
 
-pub struct WorkerFuture<T, E> {
+#[cfg(not(feature = "multicore"))]
-    future: CpuFuture<T, E>
+mod implementation {
-}
+    use futures::{future, Future, IntoFuture, Poll};
 
-impl<T: Send + 'static, E: Send + 'static> Future for WorkerFuture<T, E> {
+    #[derive(Clone)]
-    type Item = T;
+    pub struct Worker;
-    type Error = E;
 
-    fn poll(&mut self) -> Poll<Self::Item, Self::Error>
+    impl Worker {
-    {
+        pub fn new() -> Worker {
-        self.future.poll()
+            Worker
+        }
+
+        pub fn log_num_cpus(&self) -> u32 {
+            0
+        }
+
+        pub fn compute<F, R>(&self, f: F) -> R::Future
+        where
+            F: FnOnce() -> R + Send + 'static,
+            R: IntoFuture + 'static,
+            R::Future: Send + 'static,
+            R::Item: Send + 'static,
+            R::Error: Send + 'static,
+        {
+            f().into_future()
+        }
+
+        pub fn scope<F, R>(&self, elements: usize, f: F) -> R
+        where
+            F: FnOnce(&DummyScope, usize) -> R,
+        {
+            f(&DummyScope, elements)
+        }
+    }
+
+    pub struct WorkerFuture<T, E> {
+        future: future::FutureResult<T, E>,
+    }
+
+    impl<T: Send + 'static, E: Send + 'static> Future for WorkerFuture<T, E> {
+        type Item = T;
+        type Error = E;
+
+        fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+            self.future.poll()
+        }
+    }
+
+    pub struct DummyScope;
+
+    impl DummyScope {
+        pub fn spawn<F: FnOnce()>(&self, f: F) {
+            f();
+        }
     }
 }
 
-fn log2_floor(num: usize) -> u32 {
+pub use self::implementation::*;
-    assert!(num > 0);
-
-    let mut pow = 0;
-
-    while (1 << (pow+1)) <= num {
-        pow += 1;
-    }
-
-    pow
-}
-
-#[test]
-fn test_log2_floor() {
-    assert_eq!(log2_floor(1), 0);
-    assert_eq!(log2_floor(2), 1);
-    assert_eq!(log2_floor(3), 1);
-    assert_eq!(log2_floor(4), 2);
-    assert_eq!(log2_floor(5), 2);
-    assert_eq!(log2_floor(6), 2);
-    assert_eq!(log2_floor(7), 2);
-    assert_eq!(log2_floor(8), 3);
-}

bellman/src/multiexp.rs

@@ -1,17 +1,11 @@
-use pairing::{
-    CurveAffine,
-    CurveProjective,
-    Engine,
-    PrimeField,
-    Field,
-    PrimeFieldRepr
-};
-use std::sync::Arc;
-use std::io;
-use bit_vec::{self, BitVec};
-use std::iter;
-use futures::{Future};
 use super::multicore::Worker;
+use bit_vec::{self, BitVec};
+use ff::{Field, PrimeField, PrimeFieldRepr, ScalarEngine};
+use futures::Future;
+use group::{CurveAffine, CurveProjective};
+use std::io;
+use std::iter;
+use std::sync::Arc;
 
 use super::SynthesisError;
 
@@ -25,7 +19,10 @@ pub trait SourceBuilder<G: CurveAffine>: Send + Sync + 'static + Clone {
 /// A source of bases, like an iterator.
 pub trait Source<G: CurveAffine> {
     /// Parses the element from the source. Fails if the point is at infinity.
-    fn add_assign_mixed(&mut self, to: &mut <G as CurveAffine>::Projective) -> Result<(), SynthesisError>;
+    fn add_assign_mixed(
+        &mut self,
+        to: &mut <G as CurveAffine>::Projective,
+    ) -> Result<(), SynthesisError>;
 
     /// Skips `amt` elements from the source, avoiding deserialization.
     fn skip(&mut self, amt: usize) -> Result<(), SynthesisError>;
@@ -40,13 +37,20 @@ impl<G: CurveAffine> SourceBuilder<G> for (Arc<Vec<G>>, usize) {
 }
 
 impl<G: CurveAffine> Source<G> for (Arc<Vec<G>>, usize) {
-    fn add_assign_mixed(&mut self, to: &mut <G as CurveAffine>::Projective) -> Result<(), SynthesisError> {
+    fn add_assign_mixed(
+        &mut self,
+        to: &mut <G as CurveAffine>::Projective,
+    ) -> Result<(), SynthesisError> {
         if self.0.len() <= self.1 {
-            return Err(io::Error::new(io::ErrorKind::UnexpectedEof, "expected more bases from source").into());
+            return Err(io::Error::new(
+                io::ErrorKind::UnexpectedEof,
+                "expected more bases from source",
+            )
+            .into());
         }
 
         if self.0[self.1].is_zero() {
-            return Err(SynthesisError::UnexpectedIdentity)
+            return Err(SynthesisError::UnexpectedIdentity);
         }
 
         to.add_assign_mixed(&self.0[self.1]);
@@ -58,7 +62,11 @@ impl<G: CurveAffine> Source<G> for (Arc<Vec<G>>, usize) {
 
     fn skip(&mut self, amt: usize) -> Result<(), SynthesisError> {
         if self.0.len() <= self.1 {
-            return Err(io::Error::new(io::ErrorKind::UnexpectedEof, "expected more bases from source").into());
+            return Err(io::Error::new(
+                io::ErrorKind::UnexpectedEof,
+                "expected more bases from source",
+            )
+            .into());
         }
 
         self.1 += amt;
@@ -69,7 +77,7 @@ impl<G: CurveAffine> Source<G> for (Arc<Vec<G>>, usize) {
 
 pub trait QueryDensity {
     /// Returns whether the base exists.
-    type Iter: Iterator<Item=bool>;
+    type Iter: Iterator<Item = bool>;
 
     fn iter(self) -> Self::Iter;
     fn get_query_size(self) -> Option<usize>;
@@ -98,7 +106,7 @@ impl<'a> QueryDensity for &'a FullDensity {
 
 pub struct DensityTracker {
     bv: BitVec,
-    total_density: usize
+    total_density: usize,
 }
 
 impl<'a> QueryDensity for &'a DensityTracker {
@@ -117,7 +125,7 @@ impl DensityTracker {
     pub fn new() -> DensityTracker {
         DensityTracker {
             bv: BitVec::new(),
-            total_density: 0
+            total_density: 0,
         }
     }
 
@@ -141,15 +149,16 @@ fn multiexp_inner<Q, D, G, S>(
     pool: &Worker,
     bases: S,
     density_map: D,
-    exponents: Arc<Vec<<<G::Engine as Engine>::Fr as PrimeField>::Repr>>,
+    exponents: Arc<Vec<<<G::Engine as ScalarEngine>::Fr as PrimeField>::Repr>>,
     mut skip: u32,
     c: u32,
-    handle_trivial: bool
+    handle_trivial: bool,
-) -> Box<Future<Item=<G as CurveAffine>::Projective, Error=SynthesisError>>
+) -> Box<Future<Item = <G as CurveAffine>::Projective, Error = SynthesisError>>
-    where for<'a> &'a Q: QueryDensity,
+where
-          D: Send + Sync + 'static + Clone + AsRef<Q>,
+    for<'a> &'a Q: QueryDensity,
-          G: CurveAffine,
+    D: Send + Sync + 'static + Clone + AsRef<Q>,
-          S: SourceBuilder<G>
+    G: CurveAffine,
+    S: SourceBuilder<G>,
 {
     // Perform this region of the multiexp
     let this = {
@@ -167,8 +176,8 @@ fn multiexp_inner<Q, D, G, S>(
             // Create space for the buckets
             let mut buckets = vec![<G as CurveAffine>::Projective::zero(); (1 << c) - 1];
 
-            let zero = <G::Engine as Engine>::Fr::zero().into_repr();
+            let zero = <G::Engine as ScalarEngine>::Fr::zero().into_repr();
-            let one = <G::Engine as Engine>::Fr::one().into_repr();
+            let one = <G::Engine as ScalarEngine>::Fr::one().into_repr();
 
             // Sort the bases into buckets
             for (&exp, density) in exponents.iter().zip(density_map.as_ref().iter()) {
@@ -211,23 +220,31 @@ fn multiexp_inner<Q, D, G, S>(
 
     skip += c;
 
-    if skip >= <G::Engine as Engine>::Fr::NUM_BITS {
+    if skip >= <G::Engine as ScalarEngine>::Fr::NUM_BITS {
         // There isn't another region.
         Box::new(this)
     } else {
         // There's another region more significant. Calculate and join it with
         // this region recursively.
         Box::new(
-            this.join(multiexp_inner(pool, bases, density_map, exponents, skip, c, false))
+            this.join(multiexp_inner(
-                .map(move |(this, mut higher)| {
+                pool,
-                    for _ in 0..c {
+                bases,
-                        higher.double();
+                density_map,
-                    }
+                exponents,
+                skip,
+                c,
+                false,
+            ))
+            .map(move |(this, mut higher)| {
+                for _ in 0..c {
+                    higher.double();
+                }
 
-                    higher.add_assign(&this);
+                higher.add_assign(&this);
 
-                    higher
+                higher
-                })
+            }),
         )
     }
 }
@@ -238,12 +255,13 @@ pub fn multiexp<Q, D, G, S>(
     pool: &Worker,
     bases: S,
     density_map: D,
-    exponents: Arc<Vec<<<G::Engine as Engine>::Fr as PrimeField>::Repr>>
+    exponents: Arc<Vec<<<G::Engine as ScalarEngine>::Fr as PrimeField>::Repr>>,
-) -> Box<Future<Item=<G as CurveAffine>::Projective, Error=SynthesisError>>
+) -> Box<Future<Item = <G as CurveAffine>::Projective, Error = SynthesisError>>
-    where for<'a> &'a Q: QueryDensity,
+where
-          D: Send + Sync + 'static + Clone + AsRef<Q>,
+    for<'a> &'a Q: QueryDensity,
-          G: CurveAffine,
+    D: Send + Sync + 'static + Clone + AsRef<Q>,
-          S: SourceBuilder<G>
+    G: CurveAffine,
+    S: SourceBuilder<G>,
 {
     let c = if exponents.len() < 32 {
         3u32
@@ -261,13 +279,13 @@ pub fn multiexp<Q, D, G, S>(
     multiexp_inner(pool, bases, density_map, exponents, 0, c, true)
 }
 
+#[cfg(feature = "pairing")]
 #[test]
 fn test_with_bls12() {
     fn naive_multiexp<G: CurveAffine>(
         bases: Arc<Vec<G>>,
-        exponents: Arc<Vec<<G::Scalar as PrimeField>::Repr>>
+        exponents: Arc<Vec<<G::Scalar as PrimeField>::Repr>>,
-    ) -> G::Projective
+    ) -> G::Projective {
-    {
         assert_eq!(bases.len(), exponents.len());
 
         let mut acc = G::Projective::zero();
@@ -279,25 +297,28 @@ fn test_with_bls12() {
         acc
     }
 
-    use rand::{self, Rand};
+    use pairing::{bls12_381::Bls12, Engine};
-    use pairing::bls12_381::Bls12;
+    use rand;
 
     const SAMPLES: usize = 1 << 14;
 
     let rng = &mut rand::thread_rng();
-    let v = Arc::new((0..SAMPLES).map(|_| <Bls12 as Engine>::Fr::rand(rng).into_repr()).collect::<Vec<_>>());
+    let v = Arc::new(
-    let g = Arc::new((0..SAMPLES).map(|_| <Bls12 as Engine>::G1::rand(rng).into_affine()).collect::<Vec<_>>());
+        (0..SAMPLES)
+            .map(|_| <Bls12 as ScalarEngine>::Fr::random(rng).into_repr())
+            .collect::<Vec<_>>(),
+    );
+    let g = Arc::new(
+        (0..SAMPLES)
+            .map(|_| <Bls12 as Engine>::G1::random(rng).into_affine())
+            .collect::<Vec<_>>(),
+    );
 
     let naive = naive_multiexp(g.clone(), v.clone());
 
     let pool = Worker::new();
 
-    let fast = multiexp(
+    let fast = multiexp(&pool, (g, 0), FullDensity, v).wait().unwrap();
-        &pool,
-        (g, 0),
-        FullDensity,
-        v
-    ).wait().unwrap();
 
     assert_eq!(naive, fast);
 }

bellman/tests/mimc.rs

@@ -1,45 +1,34 @@
 extern crate bellman;
+extern crate ff;
 extern crate pairing;
 extern crate rand;
 
 // For randomness (during paramgen and proof generation)
-use rand::{thread_rng, Rng};
+use rand::thread_rng;
 
 // For benchmarking
 use std::time::{Duration, Instant};
 
 // Bring in some tools for using pairing-friendly curves
-use pairing::{
+use ff::{Field, ScalarEngine};
-    Engine,
+use pairing::Engine;
-    Field
-};
 
 // We're going to use the BLS12-381 pairing-friendly elliptic curve.
-use pairing::bls12_381::{
+use pairing::bls12_381::Bls12;
-    Bls12
-};
 
 // We'll use these interfaces to construct our circuit.
-use bellman::{
+use bellman::{Circuit, ConstraintSystem, SynthesisError};
-    Circuit,
-    ConstraintSystem,
-    SynthesisError
-};
 
 // We're going to use the Groth16 proving system.
 use bellman::groth16::{
-    Proof,
+    create_random_proof, generate_random_parameters, prepare_verifying_key, verify_proof, Proof,
-    generate_random_parameters,
-    prepare_verifying_key,
-    create_random_proof,
-    verify_proof,
 };
 
 const MIMC_ROUNDS: usize = 322;
 
 /// This is an implementation of MiMC, specifically a
 /// variant named `LongsightF322p3` for BLS12-381.
-/// See http://eprint.iacr.org/2016/492 for more 
+/// See http://eprint.iacr.org/2016/492 for more
 /// information about this construction.
 ///
 /// ```
@@ -50,12 +39,7 @@ const MIMC_ROUNDS: usize = 322;
 ///     return xL
 /// }
 /// ```
-fn mimc<E: Engine>(
+fn mimc<E: Engine>(mut xl: E::Fr, mut xr: E::Fr, constants: &[E::Fr]) -> E::Fr {
-    mut xl: E::Fr,
-    mut xr: E::Fr,
-    constants: &[E::Fr]
-) -> E::Fr
-{
     assert_eq!(constants.len(), MIMC_ROUNDS);
 
     for i in 0..MIMC_ROUNDS {
@@ -77,31 +61,29 @@ fn mimc<E: Engine>(
 struct MiMCDemo<'a, E: Engine> {
     xl: Option<E::Fr>,
     xr: Option<E::Fr>,
-    constants: &'a [E::Fr]
+    constants: &'a [E::Fr],
 }
 
 /// Our demo circuit implements this `Circuit` trait which
 /// is used during paramgen and proving in order to
 /// synthesize the constraint system.
 impl<'a, E: Engine> Circuit<E> for MiMCDemo<'a, E> {
-    fn synthesize<CS: ConstraintSystem<E>>(
+    fn synthesize<CS: ConstraintSystem<E>>(self, cs: &mut CS) -> Result<(), SynthesisError> {
-        self,
-        cs: &mut CS
-    ) -> Result<(), SynthesisError>
-    {
         assert_eq!(self.constants.len(), MIMC_ROUNDS);
 
         // Allocate the first component of the preimage.
         let mut xl_value = self.xl;
-        let mut xl = cs.alloc(|| "preimage xl", || {
+        let mut xl = cs.alloc(
-            xl_value.ok_or(SynthesisError::AssignmentMissing)
+            || "preimage xl",
-        })?;
+            || xl_value.ok_or(SynthesisError::AssignmentMissing),
+        )?;
 
         // Allocate the second component of the preimage.
         let mut xr_value = self.xr;
-        let mut xr = cs.alloc(|| "preimage xr", || {
+        let mut xr = cs.alloc(
-            xr_value.ok_or(SynthesisError::AssignmentMissing)
+            || "preimage xr",
-        })?;
+            || xr_value.ok_or(SynthesisError::AssignmentMissing),
+        )?;
 
         for i in 0..MIMC_ROUNDS {
             // xL, xR := xR + (xL + Ci)^3, xL
@@ -113,15 +95,16 @@ impl<'a, E: Engine> Circuit<E> for MiMCDemo<'a, E> {
                 e.square();
                 e
             });
-            let mut tmp = cs.alloc(|| "tmp", || {
+            let mut tmp = cs.alloc(
-                tmp_value.ok_or(SynthesisError::AssignmentMissing)
+                || "tmp",
-            })?;
+                || tmp_value.ok_or(SynthesisError::AssignmentMissing),
+            )?;
 
             cs.enforce(
                 || "tmp = (xL + Ci)^2",
                 |lc| lc + xl + (self.constants[i], CS::one()),
                 |lc| lc + xl + (self.constants[i], CS::one()),
-                |lc| lc + tmp
+                |lc| lc + tmp,
             );
 
             // new_xL = xR + (xL + Ci)^3
@@ -134,23 +117,25 @@ impl<'a, E: Engine> Circuit<E> for MiMCDemo<'a, E> {
                 e
             });
 
-            let mut new_xl = if i == (MIMC_ROUNDS-1) {
+            let mut new_xl = if i == (MIMC_ROUNDS - 1) {
                 // This is the last round, xL is our image and so
                 // we allocate a public input.
-                cs.alloc_input(|| "image", || {
+                cs.alloc_input(
-                    new_xl_value.ok_or(SynthesisError::AssignmentMissing)
+                    || "image",
-                })?
+                    || new_xl_value.ok_or(SynthesisError::AssignmentMissing),
+                )?
             } else {
-                cs.alloc(|| "new_xl", || {
+                cs.alloc(
-                    new_xl_value.ok_or(SynthesisError::AssignmentMissing)
+                    || "new_xl",
-                })?
+                    || new_xl_value.ok_or(SynthesisError::AssignmentMissing),
+                )?
             };
 
             cs.enforce(
                 || "new_xL = xR + (xL + Ci)^3",
                 |lc| lc + tmp,
                 |lc| lc + xl + (self.constants[i], CS::one()),
-                |lc| lc + new_xl - xr
+                |lc| lc + new_xl - xr,
             );
 
             // xR = xL
@@ -173,7 +158,9 @@ fn test_mimc() {
     let rng = &mut thread_rng();
 
     // Generate the MiMC round constants
-    let constants = (0..MIMC_ROUNDS).map(|_| rng.gen()).collect::<Vec<_>>();
+    let constants = (0..MIMC_ROUNDS)
+        .map(|_| <Bls12 as ScalarEngine>::Fr::random(rng))
+        .collect::<Vec<_>>();
 
     println!("Creating parameters...");
 
@@ -182,7 +169,7 @@ fn test_mimc() {
         let c = MiMCDemo::<Bls12> {
             xl: None,
             xr: None,
-            constants: &constants
+            constants: &constants,
         };
 
         generate_random_parameters(c, rng).unwrap()
@@ -204,8 +191,8 @@ fn test_mimc() {
 
     for _ in 0..SAMPLES {
         // Generate a random preimage and compute the image
-        let xl = rng.gen();
+        let xl = <Bls12 as ScalarEngine>::Fr::random(rng);
-        let xr = rng.gen();
+        let xr = <Bls12 as ScalarEngine>::Fr::random(rng);
         let image = mimc::<Bls12>(xl, xr, &constants);
 
         proof_vec.truncate(0);
@@ -217,7 +204,7 @@ fn test_mimc() {
             let c = MiMCDemo {
                 xl: Some(xl),
                 xr: Some(xr),
-                constants: &constants
+                constants: &constants,
             };
 
             // Create a groth16 proof with our parameters.
@@ -231,20 +218,16 @@ fn test_mimc() {
         let start = Instant::now();
         let proof = Proof::read(&proof_vec[..]).unwrap();
         // Check the proof
-        assert!(verify_proof(
+        assert!(verify_proof(&pvk, &proof, &[image]).unwrap());
-            &pvk,
-            &proof,
-            &[image]
-        ).unwrap());
         total_verifying += start.elapsed();
     }
     let proving_avg = total_proving / SAMPLES;
-    let proving_avg = proving_avg.subsec_nanos() as f64 / 1_000_000_000f64
+    let proving_avg =
-                      + (proving_avg.as_secs() as f64);
+        proving_avg.subsec_nanos() as f64 / 1_000_000_000f64 + (proving_avg.as_secs() as f64);
 
     let verifying_avg = total_verifying / SAMPLES;
-    let verifying_avg = verifying_avg.subsec_nanos() as f64 / 1_000_000_000f64
+    let verifying_avg =
-                      + (verifying_avg.as_secs() as f64);
+        verifying_avg.subsec_nanos() as f64 / 1_000_000_000f64 + (verifying_avg.as_secs() as f64);
 
     println!("Average proving time: {:?} seconds", proving_avg);
     println!("Average verifying time: {:?} seconds", verifying_avg);

ff/.gitignore

@@ -1,3 +1,3 @@
-/target/
+target/
 **/*.rs.bk
 Cargo.lock

ff/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "ff"
+version = "0.4.0"
+authors = ["Sean Bowe <ewillbefull@gmail.com>"]
+description = "Library for building and interfacing with finite fields"
+documentation = "https://docs.rs/ff/"
+homepage = "https://github.com/ebfull/ff"
+license = "MIT/Apache-2.0"
+repository = "https://github.com/ebfull/ff"
+
+[dependencies]
+byteorder = "1"
+ff_derive = { version = "0.3.0", path = "ff_derive", optional = true }
+rand_core = "0.5"
+
+[features]
+default = []
+derive = ["ff_derive"]

ff/LICENSE-MIT

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2017 Zcash Company
+Copyright (c) 2017 Sean Bowe
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

ff/README.md

@@ -0,0 +1,60 @@
+# ff
+
+`ff` is a finite field library written in pure Rust, with no `unsafe{}` code.
+
+## Disclaimers
+
+* This library does not provide constant-time guarantees.
+
+## Usage
+
+Add the `ff` crate to your `Cargo.toml`:
+
+```toml
+[dependencies]
+ff = "0.4"
+```
+
+The `ff` crate contains `Field`, `PrimeField`, `PrimeFieldRepr` and `SqrtField` traits. See the **[documentation](https://docs.rs/ff/0.4.0/ff/)** for more.
+
+### #![derive(PrimeField)]
+
+If you need an implementation of a prime field, this library also provides a procedural macro that will expand into an efficient implementation of a prime field when supplied with the modulus. `PrimeFieldGenerator` must be an element of Fp of p-1 order, that is also quadratic nonresidue.
+
+First, enable the `derive` crate feature:
+
+```toml
+[dependencies]
+ff = { version = "0.4", features = ["derive"] }
+```
+
+And then use the macro like so:
+
+```rust
+extern crate rand;
+#[macro_use]
+extern crate ff;
+
+#[derive(PrimeField)]
+#[PrimeFieldModulus = "52435875175126190479447740508185965837690552500527637822603658699938581184513"]
+#[PrimeFieldGenerator = "7"]
+struct Fp(FpRepr);
+```
+
+And that's it! `Fp` now implements `Field` and `PrimeField`. `Fp` will also implement `SqrtField` if supported. The library implements `FpRepr` itself and derives `PrimeFieldRepr` for it.
+
+## License
+
+Licensed under either of
+
+ * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
+ * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally
+submitted for inclusion in the work by you, as defined in the Apache-2.0
+license, shall be dual licensed as above, without any additional terms or
+conditions.

ff/ff_derive/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "ff_derive"
+version = "0.3.0"
+authors = ["Sean Bowe <ewillbefull@gmail.com>"]
+description = "Procedural macro library used to build custom prime field implementations"
+documentation = "https://docs.rs/ff/"
+homepage = "https://github.com/ebfull/ff"
+license = "MIT/Apache-2.0"
+repository = "https://github.com/ebfull/ff"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+num-bigint = "0.2"
+num-traits = "0.2"
+num-integer = "0.1"
+proc-macro2 = "0.4"
+quote = "0.6"
+syn = "0.14"

ff/src/lib.rs

@@ -0,0 +1,396 @@
+#![allow(unused_imports)]
+
+extern crate byteorder;
+extern crate rand_core;
+
+#[cfg(feature = "derive")]
+#[macro_use]
+extern crate ff_derive;
+
+#[cfg(feature = "derive")]
+pub use ff_derive::*;
+
+use rand_core::RngCore;
+use std::error::Error;
+use std::fmt;
+use std::io::{self, Read, Write};
+
+/// This trait represents an element of a field.
+pub trait Field:
+    Sized + Eq + Copy + Clone + Send + Sync + fmt::Debug + fmt::Display + 'static
+{
+    /// Returns an element chosen uniformly at random using a user-provided RNG.
+    fn random<R: RngCore>(rng: &mut R) -> Self;
+
+    /// Returns the zero element of the field, the additive identity.
+    fn zero() -> Self;
+
+    /// Returns the one element of the field, the multiplicative identity.
+    fn one() -> Self;
+
+    /// Returns true iff this element is zero.
+    fn is_zero(&self) -> bool;
+
+    /// Squares this element.
+    fn square(&mut self);
+
+    /// Doubles this element.
+    fn double(&mut self);
+
+    /// Negates this element.
+    fn negate(&mut self);
+
+    /// Adds another element to this element.
+    fn add_assign(&mut self, other: &Self);
+
+    /// Subtracts another element from this element.
+    fn sub_assign(&mut self, other: &Self);
+
+    /// Multiplies another element by this element.
+    fn mul_assign(&mut self, other: &Self);
+
+    /// Computes the multiplicative inverse of this element, if nonzero.
+    fn inverse(&self) -> Option<Self>;
+
+    /// Exponentiates this element by a power of the base prime modulus via
+    /// the Frobenius automorphism.
+    fn frobenius_map(&mut self, power: usize);
+
+    /// Exponentiates this element by a number represented with `u64` limbs,
+    /// least significant digit first.
+    fn pow<S: AsRef<[u64]>>(&self, exp: S) -> Self {
+        let mut res = Self::one();
+
+        let mut found_one = false;
+
+        for i in BitIterator::new(exp) {
+            if found_one {
+                res.square();
+            } else {
+                found_one = i;
+            }
+
+            if i {
+                res.mul_assign(self);
+            }
+        }
+
+        res
+    }
+}
+
+/// This trait represents an element of a field that has a square root operation described for it.
+pub trait SqrtField: Field {
+    /// Returns the Legendre symbol of the field element.
+    fn legendre(&self) -> LegendreSymbol;
+
+    /// Returns the square root of the field element, if it is
+    /// quadratic residue.
+    fn sqrt(&self) -> Option<Self>;
+}
+
+/// This trait represents a wrapper around a biginteger which can encode any element of a particular
+/// prime field. It is a smart wrapper around a sequence of `u64` limbs, least-significant digit
+/// first.
+pub trait PrimeFieldRepr:
+    Sized
+    + Copy
+    + Clone
+    + Eq
+    + Ord
+    + Send
+    + Sync
+    + Default
+    + fmt::Debug
+    + fmt::Display
+    + 'static
+    + AsRef<[u64]>
+    + AsMut<[u64]>
+    + From<u64>
+{
+    /// Subtract another represetation from this one.
+    fn sub_noborrow(&mut self, other: &Self);
+
+    /// Add another representation to this one.
+    fn add_nocarry(&mut self, other: &Self);
+
+    /// Compute the number of bits needed to encode this number. Always a
+    /// multiple of 64.
+    fn num_bits(&self) -> u32;
+
+    /// Returns true iff this number is zero.
+    fn is_zero(&self) -> bool;
+
+    /// Returns true iff this number is odd.
+    fn is_odd(&self) -> bool;
+
+    /// Returns true iff this number is even.
+    fn is_even(&self) -> bool;
+
+    /// Performs a rightwise bitshift of this number, effectively dividing
+    /// it by 2.
+    fn div2(&mut self);
+
+    /// Performs a rightwise bitshift of this number by some amount.
+    fn shr(&mut self, amt: u32);
+
+    /// Performs a leftwise bitshift of this number, effectively multiplying
+    /// it by 2. Overflow is ignored.
+    fn mul2(&mut self);
+
+    /// Performs a leftwise bitshift of this number by some amount.
+    fn shl(&mut self, amt: u32);
+
+    /// Writes this `PrimeFieldRepr` as a big endian integer.
+    fn write_be<W: Write>(&self, mut writer: W) -> io::Result<()> {
+        use byteorder::{BigEndian, WriteBytesExt};
+
+        for digit in self.as_ref().iter().rev() {
+            writer.write_u64::<BigEndian>(*digit)?;
+        }
+
+        Ok(())
+    }
+
+    /// Reads a big endian integer into this representation.
+    fn read_be<R: Read>(&mut self, mut reader: R) -> io::Result<()> {
+        use byteorder::{BigEndian, ReadBytesExt};
+
+        for digit in self.as_mut().iter_mut().rev() {
+            *digit = reader.read_u64::<BigEndian>()?;
+        }
+
+        Ok(())
+    }
+
+    /// Writes this `PrimeFieldRepr` as a little endian integer.
+    fn write_le<W: Write>(&self, mut writer: W) -> io::Result<()> {
+        use byteorder::{LittleEndian, WriteBytesExt};
+
+        for digit in self.as_ref().iter() {
+            writer.write_u64::<LittleEndian>(*digit)?;
+        }
+
+        Ok(())
+    }
+
+    /// Reads a little endian integer into this representation.
+    fn read_le<R: Read>(&mut self, mut reader: R) -> io::Result<()> {
+        use byteorder::{LittleEndian, ReadBytesExt};
+
+        for digit in self.as_mut().iter_mut() {
+            *digit = reader.read_u64::<LittleEndian>()?;
+        }
+
+        Ok(())
+    }
+}
+
+#[derive(Debug, PartialEq)]
+pub enum LegendreSymbol {
+    Zero = 0,
+    QuadraticResidue = 1,
+    QuadraticNonResidue = -1,
+}
+
+/// An error that may occur when trying to interpret a `PrimeFieldRepr` as a
+/// `PrimeField` element.
+#[derive(Debug)]
+pub enum PrimeFieldDecodingError {
+    /// The encoded value is not in the field
+    NotInField(String),
+}
+
+impl Error for PrimeFieldDecodingError {
+    fn description(&self) -> &str {
+        match *self {
+            PrimeFieldDecodingError::NotInField(..) => "not an element of the field",
+        }
+    }
+}
+
+impl fmt::Display for PrimeFieldDecodingError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        match *self {
+            PrimeFieldDecodingError::NotInField(ref repr) => {
+                write!(f, "{} is not an element of the field", repr)
+            }
+        }
+    }
+}
+
+/// This represents an element of a prime field.
+pub trait PrimeField: Field {
+    /// The prime field can be converted back and forth into this biginteger
+    /// representation.
+    type Repr: PrimeFieldRepr + From<Self>;
+
+    /// Interpret a string of numbers as a (congruent) prime field element.
+    /// Does not accept unnecessary leading zeroes or a blank string.
+    fn from_str(s: &str) -> Option<Self> {
+        if s.is_empty() {
+            return None;
+        }
+
+        if s == "0" {
+            return Some(Self::zero());
+        }
+
+        let mut res = Self::zero();
+
+        let ten = Self::from_repr(Self::Repr::from(10)).unwrap();
+
+        let mut first_digit = true;
+
+        for c in s.chars() {
+            match c.to_digit(10) {
+                Some(c) => {
+                    if first_digit {
+                        if c == 0 {
+                            return None;
+                        }
+
+                        first_digit = false;
+                    }
+
+                    res.mul_assign(&ten);
+                    res.add_assign(&Self::from_repr(Self::Repr::from(u64::from(c))).unwrap());
+                }
+                None => {
+                    return None;
+                }
+            }
+        }
+
+        Some(res)
+    }
+
+    /// Convert this prime field element into a biginteger representation.
+    fn from_repr(Self::Repr) -> Result<Self, PrimeFieldDecodingError>;
+
+    /// Convert a biginteger representation into a prime field element, if
+    /// the number is an element of the field.
+    fn into_repr(&self) -> Self::Repr;
+
+    /// Returns the field characteristic; the modulus.
+    fn char() -> Self::Repr;
+
+    /// How many bits are needed to represent an element of this field.
+    const NUM_BITS: u32;
+
+    /// How many bits of information can be reliably stored in the field element.
+    const CAPACITY: u32;
+
+    /// Returns the multiplicative generator of `char()` - 1 order. This element
+    /// must also be quadratic nonresidue.
+    fn multiplicative_generator() -> Self;
+
+    /// 2^s * t = `char()` - 1 with t odd.
+    const S: u32;
+
+    /// Returns the 2^s root of unity computed by exponentiating the `multiplicative_generator()`
+    /// by t.
+    fn root_of_unity() -> Self;
+}
+
+/// An "engine" is a collection of types (fields, elliptic curve groups, etc.)
+/// with well-defined relationships. Specific relationships (for example, a
+/// pairing-friendly curve) can be defined in a subtrait.
+pub trait ScalarEngine: Sized + 'static + Clone {
+    /// This is the scalar field of the engine's groups.
+    type Fr: PrimeField + SqrtField;
+}
+
+#[derive(Debug)]
+pub struct BitIterator<E> {
+    t: E,
+    n: usize,
+}
+
+impl<E: AsRef<[u64]>> BitIterator<E> {
+    pub fn new(t: E) -> Self {
+        let n = t.as_ref().len() * 64;
+
+        BitIterator { t, n }
+    }
+}
+
+impl<E: AsRef<[u64]>> Iterator for BitIterator<E> {
+    type Item = bool;
+
+    fn next(&mut self) -> Option<bool> {
+        if self.n == 0 {
+            None
+        } else {
+            self.n -= 1;
+            let part = self.n / 64;
+            let bit = self.n - (64 * part);
+
+            Some(self.t.as_ref()[part] & (1 << bit) > 0)
+        }
+    }
+}
+
+#[test]
+fn test_bit_iterator() {
+    let mut a = BitIterator::new([0xa953d79b83f6ab59, 0x6dea2059e200bd39]);
+    let expected = "01101101111010100010000001011001111000100000000010111101001110011010100101010011110101111001101110000011111101101010101101011001";
+
+    for e in expected.chars() {
+        assert!(a.next().unwrap() == (e == '1'));
+    }
+
+    assert!(a.next().is_none());
+
+    let expected = "1010010101111110101010000101101011101000011101110101001000011001100100100011011010001011011011010001011011101100110100111011010010110001000011110100110001100110011101101000101100011100100100100100001010011101010111110011101011000011101000111011011101011001";
+
+    let mut a = BitIterator::new([
+        0x429d5f3ac3a3b759,
+        0xb10f4c66768b1c92,
+        0x92368b6d16ecd3b4,
+        0xa57ea85ae8775219,
+    ]);
+
+    for e in expected.chars() {
+        assert!(a.next().unwrap() == (e == '1'));
+    }
+
+    assert!(a.next().is_none());
+}
+
+pub use self::arith_impl::*;
+
+mod arith_impl {
+    /// Calculate a - b - borrow, returning the result and modifying
+    /// the borrow value.
+    #[inline(always)]
+    pub fn sbb(a: u64, b: u64, borrow: &mut u64) -> u64 {
+        let tmp = (1u128 << 64) + u128::from(a) - u128::from(b) - u128::from(*borrow);
+
+        *borrow = if tmp >> 64 == 0 { 1 } else { 0 };
+
+        tmp as u64
+    }
+
+    /// Calculate a + b + carry, returning the sum and modifying the
+    /// carry value.
+    #[inline(always)]
+    pub fn adc(a: u64, b: u64, carry: &mut u64) -> u64 {
+        let tmp = u128::from(a) + u128::from(b) + u128::from(*carry);
+
+        *carry = (tmp >> 64) as u64;
+
+        tmp as u64
+    }
+
+    /// Calculate a + (b * c) + carry, returning the least significant digit
+    /// and setting carry to the most significant digit.
+    #[inline(always)]
+    pub fn mac_with_carry(a: u64, b: u64, c: u64, carry: &mut u64) -> u64 {
+        let tmp = (u128::from(a)) + u128::from(b) * u128::from(c) + u128::from(*carry);
+
+        *carry = (tmp >> 64) as u64;
+
+        tmp as u64
+    }
+}

group/COPYRIGHT

@@ -1,7 +1,7 @@
-Copyrights in the "zip32" library are retained by their contributors. No
+Copyrights in the "group" library are retained by their contributors. No
-copyright assignment is required to contribute to the "zip32" library.
+copyright assignment is required to contribute to the "group" library.
 
-The "zip32" library is licensed under either of
+The "group" library is licensed under either of
 
  * Apache License, Version 2.0, (see ./LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
  * MIT license (see ./LICENSE-MIT or http://opensource.org/licenses/MIT)

group/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "group"
+version = "0.1.0"
+authors = [
+    "Sean Bowe <ewillbefull@gmail.com>",
+    "Jack Grigg <jack@z.cash>",
+]
+license = "MIT/Apache-2.0"
+
+description = "Elliptic curve group traits and utilities"
+documentation = "https://docs.rs/group/"
+homepage = "https://github.com/ebfull/group"
+repository = "https://github.com/ebfull/group"
+
+[dependencies]
+ff = { path = "../ff" }
+rand = "0.7"
+rand_xorshift = "0.2"

group/README.md

@@ -1,4 +1,4 @@
-# zip32 [![Crates.io](https://img.shields.io/crates/v/zip32.svg)](https://crates.io/crates/zip32) #
+# group [![Crates.io](https://img.shields.io/crates/v/group.svg)](https://crates.io/crates/group) #
 
 ## License
 

group/src/lib.rs

@@ -0,0 +1,191 @@
+extern crate ff;
+extern crate rand;
+extern crate rand_xorshift;
+
+use ff::{PrimeField, PrimeFieldDecodingError, ScalarEngine, SqrtField};
+use rand::RngCore;
+use std::error::Error;
+use std::fmt;
+
+pub mod tests;
+
+mod wnaf;
+pub use self::wnaf::Wnaf;
+
+/// Projective representation of an elliptic curve point guaranteed to be
+/// in the correct prime order subgroup.
+pub trait CurveProjective:
+    PartialEq + Eq + Sized + Copy + Clone + Send + Sync + fmt::Debug + fmt::Display + 'static
+{
+    type Engine: ScalarEngine<Fr = Self::Scalar>;
+    type Scalar: PrimeField + SqrtField;
+    type Base: SqrtField;
+    type Affine: CurveAffine<Projective = Self, Scalar = Self::Scalar>;
+
+    /// Returns an element chosen uniformly at random using a user-provided RNG.
+    fn random<R: RngCore>(rng: &mut R) -> Self;
+
+    /// Returns the additive identity.
+    fn zero() -> Self;
+
+    /// Returns a fixed generator of unknown exponent.
+    fn one() -> Self;
+
+    /// Determines if this point is the point at infinity.
+    fn is_zero(&self) -> bool;
+
+    /// Normalizes a slice of projective elements so that
+    /// conversion to affine is cheap.
+    fn batch_normalization(v: &mut [Self]);
+
+    /// Checks if the point is already "normalized" so that
+    /// cheap affine conversion is possible.
+    fn is_normalized(&self) -> bool;
+
+    /// Doubles this element.
+    fn double(&mut self);
+
+    /// Adds another element to this element.
+    fn add_assign(&mut self, other: &Self);
+
+    /// Subtracts another element from this element.
+    fn sub_assign(&mut self, other: &Self) {
+        let mut tmp = *other;
+        tmp.negate();
+        self.add_assign(&tmp);
+    }
+
+    /// Adds an affine element to this element.
+    fn add_assign_mixed(&mut self, other: &Self::Affine);
+
+    /// Negates this element.
+    fn negate(&mut self);
+
+    /// Performs scalar multiplication of this element.
+    fn mul_assign<S: Into<<Self::Scalar as PrimeField>::Repr>>(&mut self, other: S);
+
+    /// Converts this element into its affine representation.
+    fn into_affine(&self) -> Self::Affine;
+
+    /// Recommends a wNAF window table size given a scalar. Always returns a number
+    /// between 2 and 22, inclusive.
+    fn recommended_wnaf_for_scalar(scalar: <Self::Scalar as PrimeField>::Repr) -> usize;
+
+    /// Recommends a wNAF window size given the number of scalars you intend to multiply
+    /// a base by. Always returns a number between 2 and 22, inclusive.
+    fn recommended_wnaf_for_num_scalars(num_scalars: usize) -> usize;
+}
+
+/// Affine representation of an elliptic curve point guaranteed to be
+/// in the correct prime order subgroup.
+pub trait CurveAffine:
+    Copy + Clone + Sized + Send + Sync + fmt::Debug + fmt::Display + PartialEq + Eq + 'static
+{
+    type Engine: ScalarEngine<Fr = Self::Scalar>;
+    type Scalar: PrimeField + SqrtField;
+    type Base: SqrtField;
+    type Projective: CurveProjective<Affine = Self, Scalar = Self::Scalar>;
+    type Uncompressed: EncodedPoint<Affine = Self>;
+    type Compressed: EncodedPoint<Affine = Self>;
+
+    /// Returns the additive identity.
+    fn zero() -> Self;
+
+    /// Returns a fixed generator of unknown exponent.
+    fn one() -> Self;
+
+    /// Determines if this point represents the point at infinity; the
+    /// additive identity.
+    fn is_zero(&self) -> bool;
+
+    /// Negates this element.
+    fn negate(&mut self);
+
+    /// Performs scalar multiplication of this element with mixed addition.
+    fn mul<S: Into<<Self::Scalar as PrimeField>::Repr>>(&self, other: S) -> Self::Projective;
+
+    /// Converts this element into its affine representation.
+    fn into_projective(&self) -> Self::Projective;
+
+    /// Converts this element into its compressed encoding, so long as it's not
+    /// the point at infinity.
+    fn into_compressed(&self) -> Self::Compressed {
+        <Self::Compressed as EncodedPoint>::from_affine(*self)
+    }
+
+    /// Converts this element into its uncompressed encoding, so long as it's not
+    /// the point at infinity.
+    fn into_uncompressed(&self) -> Self::Uncompressed {
+        <Self::Uncompressed as EncodedPoint>::from_affine(*self)
+    }
+}
+
+/// An encoded elliptic curve point, which should essentially wrap a `[u8; N]`.
+pub trait EncodedPoint:
+    Sized + Send + Sync + AsRef<[u8]> + AsMut<[u8]> + Clone + Copy + 'static
+{
+    type Affine: CurveAffine;
+
+    /// Creates an empty representation.
+    fn empty() -> Self;
+
+    /// Returns the number of bytes consumed by this representation.
+    fn size() -> usize;
+
+    /// Converts an `EncodedPoint` into a `CurveAffine` element,
+    /// if the encoding represents a valid element.
+    fn into_affine(&self) -> Result<Self::Affine, GroupDecodingError>;
+
+    /// Converts an `EncodedPoint` into a `CurveAffine` element,
+    /// without guaranteeing that the encoding represents a valid
+    /// element. This is useful when the caller knows the encoding is
+    /// valid already.
+    ///
+    /// If the encoding is invalid, this can break API invariants,
+    /// so caution is strongly encouraged.
+    fn into_affine_unchecked(&self) -> Result<Self::Affine, GroupDecodingError>;
+
+    /// Creates an `EncodedPoint` from an affine point, as long as the
+    /// point is not the point at infinity.
+    fn from_affine(affine: Self::Affine) -> Self;
+}
+
+/// An error that may occur when trying to decode an `EncodedPoint`.
+#[derive(Debug)]
+pub enum GroupDecodingError {
+    /// The coordinate(s) do not lie on the curve.
+    NotOnCurve,
+    /// The element is not part of the r-order subgroup.
+    NotInSubgroup,
+    /// One of the coordinates could not be decoded
+    CoordinateDecodingError(&'static str, PrimeFieldDecodingError),
+    /// The compression mode of the encoded element was not as expected
+    UnexpectedCompressionMode,
+    /// The encoding contained bits that should not have been set
+    UnexpectedInformation,
+}
+
+impl Error for GroupDecodingError {
+    fn description(&self) -> &str {
+        match *self {
+            GroupDecodingError::NotOnCurve => "coordinate(s) do not lie on the curve",
+            GroupDecodingError::NotInSubgroup => "the element is not part of an r-order subgroup",
+            GroupDecodingError::CoordinateDecodingError(..) => "coordinate(s) could not be decoded",
+            GroupDecodingError::UnexpectedCompressionMode => {
+                "encoding has unexpected compression mode"
+            }
+            GroupDecodingError::UnexpectedInformation => "encoding has unexpected information",
+        }
+    }
+}
+
+impl fmt::Display for GroupDecodingError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
+        match *self {
+            GroupDecodingError::CoordinateDecodingError(description, ref err) => {
+                write!(f, "{} decoding error: {}", description, err)
+            }
+            _ => write!(f, "{}", self.description()),
+        }
+    }
+}

group/src/tests/mod.rs

@@ -1,9 +1,14 @@
-use rand::{Rand, Rng, SeedableRng, XorShiftRng};
+use ff::{Field, PrimeField};
+use rand::SeedableRng;
+use rand_xorshift::XorShiftRng;
 
-use {CurveAffine, CurveProjective, EncodedPoint, Field};
+use {CurveAffine, CurveProjective, EncodedPoint};
 
 pub fn curve_tests<G: CurveProjective>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     // Negation edge case with zero.
     {
@@ -21,7 +26,7 @@ pub fn curve_tests<G: CurveProjective>() {
 
     // Addition edge cases with zero
     {
-        let mut r = G::rand(&mut rng);
+        let mut r = G::random(&mut rng);
         let rcopy = r;
         r.add_assign(&G::zero());
         assert_eq!(r, rcopy);
@@ -45,7 +50,7 @@ pub fn curve_tests<G: CurveProjective>() {
 
     // Transformations
     {
-        let a = G::rand(&mut rng);
+        let a = G::random(&mut rng);
         let b = a.into_affine().into_projective();
         let c = a
             .into_affine()
@@ -67,9 +72,11 @@ pub fn curve_tests<G: CurveProjective>() {
 
 fn random_wnaf_tests<G: CurveProjective>() {
     use wnaf::*;
-    use PrimeField;
 
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     {
         let mut table = vec![];
@@ -77,8 +84,8 @@ fn random_wnaf_tests<G: CurveProjective>() {
 
         for w in 2..14 {
             for _ in 0..100 {
-                let g = G::rand(&mut rng);
+                let g = G::random(&mut rng);
-                let s = G::Scalar::rand(&mut rng).into_repr();
+                let s = G::Scalar::random(&mut rng).into_repr();
                 let mut g1 = g;
                 g1.mul_assign(s);
 
@@ -95,8 +102,8 @@ fn random_wnaf_tests<G: CurveProjective>() {
         fn only_compiles_if_send<S: Send>(_: &S) {}
 
         for _ in 0..100 {
-            let g = G::rand(&mut rng);
+            let g = G::random(&mut rng);
-            let s = G::Scalar::rand(&mut rng).into_repr();
+            let s = G::Scalar::random(&mut rng).into_repr();
             let mut g1 = g;
             g1.mul_assign(s);
 
@@ -129,7 +136,8 @@ fn random_wnaf_tests<G: CurveProjective>() {
                 let mut wnaf = Wnaf::new();
                 {
                     // Populate the vectors.
-                    wnaf.base(rng.gen(), 1).scalar(rng.gen());
+                    wnaf.base(G::random(&mut rng), 1)
+                        .scalar(G::Scalar::random(&mut rng).into_repr());
                 }
                 wnaf.base(g, 1).scalar(s)
             };
@@ -137,7 +145,8 @@ fn random_wnaf_tests<G: CurveProjective>() {
                 let mut wnaf = Wnaf::new();
                 {
                     // Populate the vectors.
-                    wnaf.base(rng.gen(), 1).scalar(rng.gen());
+                    wnaf.base(G::random(&mut rng), 1)
+                        .scalar(G::Scalar::random(&mut rng).into_repr());
                 }
                 wnaf.scalar(s).base(g)
             };
@@ -145,7 +154,8 @@ fn random_wnaf_tests<G: CurveProjective>() {
                 let mut wnaf = Wnaf::new();
                 {
                     // Populate the vectors.
-                    wnaf.base(rng.gen(), 1).scalar(rng.gen());
+                    wnaf.base(G::random(&mut rng), 1)
+                        .scalar(G::Scalar::random(&mut rng).into_repr());
                 }
                 let mut shared = wnaf.base(g, 1).shared();
 
@@ -157,7 +167,8 @@ fn random_wnaf_tests<G: CurveProjective>() {
                 let mut wnaf = Wnaf::new();
                 {
                     // Populate the vectors.
-                    wnaf.base(rng.gen(), 1).scalar(rng.gen());
+                    wnaf.base(G::random(&mut rng), 1)
+                        .scalar(G::Scalar::random(&mut rng).into_repr());
                 }
                 let mut shared = wnaf.scalar(s).shared();
 
@@ -179,12 +190,15 @@ fn random_wnaf_tests<G: CurveProjective>() {
 }
 
 fn random_negation_tests<G: CurveProjective>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let r = G::rand(&mut rng);
+        let r = G::random(&mut rng);
 
-        let s = G::Scalar::rand(&mut rng);
+        let s = G::Scalar::random(&mut rng);
         let mut sneg = s;
         sneg.negate();
 
@@ -208,11 +222,14 @@ fn random_negation_tests<G: CurveProjective>() {
 }
 
 fn random_doubling_tests<G: CurveProjective>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let mut a = G::rand(&mut rng);
+        let mut a = G::random(&mut rng);
-        let mut b = G::rand(&mut rng);
+        let mut b = G::random(&mut rng);
 
         // 2(a + b)
         let mut tmp1 = a;
@@ -235,15 +252,18 @@ fn random_doubling_tests<G: CurveProjective>() {
 }
 
 fn random_multiplication_tests<G: CurveProjective>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let mut a = G::rand(&mut rng);
+        let mut a = G::random(&mut rng);
-        let mut b = G::rand(&mut rng);
+        let mut b = G::random(&mut rng);
         let a_affine = a.into_affine();
         let b_affine = b.into_affine();
 
-        let s = G::Scalar::rand(&mut rng);
+        let s = G::Scalar::random(&mut rng);
 
         // s ( a + b )
         let mut tmp1 = a;
@@ -267,12 +287,15 @@ fn random_multiplication_tests<G: CurveProjective>() {
 }
 
 fn random_addition_tests<G: CurveProjective>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let a = G::rand(&mut rng);
+        let a = G::random(&mut rng);
-        let b = G::rand(&mut rng);
+        let b = G::random(&mut rng);
-        let c = G::rand(&mut rng);
+        let c = G::random(&mut rng);
         let a_affine = a.into_affine();
         let b_affine = b.into_affine();
         let c_affine = c.into_affine();
@@ -345,10 +368,13 @@ fn random_addition_tests<G: CurveProjective>() {
 }
 
 fn random_transformation_tests<G: CurveProjective>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let g = G::rand(&mut rng);
+        let g = G::random(&mut rng);
         let g_affine = g.into_affine();
         let g_projective = g_affine.into_projective();
         assert_eq!(g, g_projective);
@@ -356,20 +382,20 @@ fn random_transformation_tests<G: CurveProjective>() {
 
     // Batch normalization
     for _ in 0..10 {
-        let mut v = (0..1000).map(|_| G::rand(&mut rng)).collect::<Vec<_>>();
+        let mut v = (0..1000).map(|_| G::random(&mut rng)).collect::<Vec<_>>();
 
         for i in &v {
             assert!(!i.is_normalized());
         }
 
-        use rand::distributions::{IndependentSample, Range};
+        use rand::distributions::{Distribution, Uniform};
-        let between = Range::new(0, 1000);
+        let between = Uniform::new(0, 1000);
         // Sprinkle in some normalized points
         for _ in 0..5 {
-            v[between.ind_sample(&mut rng)] = G::zero();
+            v[between.sample(&mut rng)] = G::zero();
         }
         for _ in 0..5 {
-            let s = between.ind_sample(&mut rng);
+            let s = between.sample(&mut rng);
             v[s] = v[s].into_affine().into_projective();
         }
 
@@ -388,7 +414,10 @@ fn random_transformation_tests<G: CurveProjective>() {
 }
 
 fn random_encoding_tests<G: CurveAffine>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     assert_eq!(
         G::zero().into_uncompressed().into_affine().unwrap(),
@@ -401,7 +430,7 @@ fn random_encoding_tests<G: CurveAffine>() {
     );
 
     for _ in 0..1000 {
-        let mut r = G::Projective::rand(&mut rng).into_affine();
+        let mut r = G::Projective::random(&mut rng).into_affine();
 
         let uncompressed = r.into_uncompressed();
         let de_uncompressed = uncompressed.into_affine().unwrap();

group/src/wnaf.rs

@@ -1,4 +1,6 @@
-use super::{CurveProjective, PrimeField, PrimeFieldRepr};
+use ff::{PrimeField, PrimeFieldRepr};
+
+use super::CurveProjective;
 
 /// Replaces the contents of `table` with a w-NAF window table for the given window size.
 pub(crate) fn wnaf_table<G: CurveProjective>(table: &mut Vec<G>, mut base: G, window: usize) {

librustzcash/Cargo.toml

@@ -15,13 +15,14 @@ crate-type = ["staticlib"]
 
 [dependencies]
 bellman = { path = "../bellman" }
+blake2b_simd = "0.5"
+blake2s_simd = "0.5"
+ff = { path = "../ff" }
 libc = "0.2"
 pairing = { path = "../pairing" }
 lazy_static = "1"
 byteorder = "1"
-rand = "0.4"
+rand_core = "0.5"
-sapling-crypto = { path = "../sapling-crypto" }
+rand_os = "0.2"
-
+zcash_primitives = { path = "../zcash_primitives" }
-[dependencies.blake2-rfc]
+zcash_proofs = { path = "../zcash_proofs" }
-git = "https://github.com/gtank/blake2-rfc"
-rev = "7a5b5fc99ae483a0043db7547fb79a6fa44b88a9"

librustzcash/include/librustzcash.h

@@ -4,6 +4,12 @@
 #include <stdint.h>
 
 extern "C" {
+#ifdef WIN32
+    typedef uint16_t codeunit;
+#else
+    typedef uint8_t codeunit;
+#endif
+
     void librustzcash_to_scalar(const unsigned char *input, unsigned char *result);
 
     void librustzcash_ask_to_ak(const unsigned char *ask, unsigned char *result);
@@ -19,11 +25,14 @@ extern "C" {
     /// Loads the zk-SNARK parameters into memory and saves
     /// paths as necessary. Only called once.
     void librustzcash_init_zksnark_params(
-        const char* spend_path,
+        const codeunit* spend_path,
+        size_t spend_path_len,
         const char* spend_hash,
-        const char* output_path,
+        const codeunit* output_path,
+        size_t output_path_len,
         const char* output_hash,
-        const char* sprout_path,
+        const codeunit* sprout_path,
+        size_t sprout_path_len,
         const char* sprout_hash
     );
 
@@ -270,6 +279,35 @@ extern "C" {
         uint64_t vpub_old,
         uint64_t vpub_new
     );
+
+    /// Derive the master ExtendedSpendingKey from a seed.
+    void librustzcash_zip32_xsk_master(
+        const unsigned char *seed,
+        size_t seedlen,
+        unsigned char *xsk_master
+    );
+
+    /// Derive a child ExtendedSpendingKey from a parent.
+    void librustzcash_zip32_xsk_derive(
+        const unsigned char *xsk_parent,
+        uint32_t i,
+        unsigned char *xsk_i
+    );
+
+    /// Derive a child ExtendedFullViewingKey from a parent.
+    bool librustzcash_zip32_xfvk_derive(
+        const unsigned char *xfvk_parent,
+        uint32_t i,
+        unsigned char *xfvk_i
+    );
+
+    /// Derive a PaymentAddress from an ExtendedFullViewingKey.
+    bool librustzcash_zip32_xfvk_address(
+        const unsigned char *xfvk,
+        const unsigned char *j,
+        unsigned char *j_ret,
+        unsigned char *addr_ret
+    );
 }
 
 #endif // LIBRUSTZCASH_INCLUDE_H_

librustzcash/src/equihash.rs

@@ -1,4 +1,4 @@
-use blake2_rfc::blake2b::{Blake2b, Blake2bResult};
+use blake2b_simd::{Hash as Blake2bHash, Params as Blake2bParams, State as Blake2bState};
 use byteorder::{BigEndian, LittleEndian, ReadBytesExt, WriteBytesExt};
 use std::io::Cursor;
 use std::mem::size_of;
@@ -33,7 +33,7 @@ impl Params {
 }
 
 impl Node {
-    fn new(p: &Params, state: &Blake2b, i: u32) -> Self {
+    fn new(p: &Params, state: &Blake2bState, i: u32) -> Self {
         let hash = generate_hash(state, i / p.indices_per_hash_output());
         let start = ((i % p.indices_per_hash_output()) * p.n / 8) as usize;
         let end = start + (p.n as usize) / 8;
@@ -99,15 +99,18 @@ impl Node {
     }
 }
 
-fn initialise_state(n: u32, k: u32, digest_len: u8) -> Blake2b {
+fn initialise_state(n: u32, k: u32, digest_len: u8) -> Blake2bState {
     let mut personalization: Vec<u8> = Vec::from("ZcashPoW");
     personalization.write_u32::<LittleEndian>(n).unwrap();
     personalization.write_u32::<LittleEndian>(k).unwrap();
 
-    Blake2b::with_params(digest_len as usize, &[], &[], &personalization)
+    Blake2bParams::new()
+        .hash_length(digest_len as usize)
+        .personal(&personalization)
+        .to_state()
 }
 
-fn generate_hash(base_state: &Blake2b, i: u32) -> Blake2bResult {
+fn generate_hash(base_state: &Blake2bState, i: u32) -> Blake2bHash {
     let mut lei = [0u8; 4];
     (&mut lei[..]).write_u32::<LittleEndian>(i).unwrap();
 
@@ -149,8 +152,7 @@ fn expand_array(vin: &[u8], bit_len: usize, byte_pad: usize) -> Vec<u8> {
                 vout[j + x] = ((
                     // Big-endian
                     acc_value >> (acc_bits + (8 * (out_width - x - 1)))
-                )
+                ) & (
-                    & (
                     // Apply bit_len_mask across byte boundaries
                     (bit_len_mask >> (8 * (out_width - x - 1))) & 0xFF
                 )) as u8;
@@ -250,7 +252,7 @@ pub fn is_valid_solution_iterative(
     return rows[0].is_zero(hash_len);
 }
 
-fn tree_validator(p: &Params, state: &Blake2b, indices: &[u32]) -> Option<Node> {
+fn tree_validator(p: &Params, state: &Blake2bState, indices: &[u32]) -> Option<Node> {
     if indices.len() > 1 {
         let end = indices.len();
         let mid = end / 2;

librustzcash/src/tests/key_agreement.rs

@@ -1,8 +1,9 @@
+use ff::{PrimeField, PrimeFieldRepr};
 use pairing::bls12_381::Bls12;
-use pairing::{PrimeField, PrimeFieldRepr};
+use rand_core::RngCore;
-use rand::{OsRng, Rng};
+use rand_os::OsRng;
-use sapling_crypto::jubjub::{edwards, JubjubBls12};
+use zcash_primitives::jubjub::{edwards, JubjubBls12};
-use sapling_crypto::primitives::{Diversifier, ViewingKey};
+use zcash_primitives::primitives::{Diversifier, ViewingKey};
 
 use {
     librustzcash_sapling_generate_r, librustzcash_sapling_ka_agree,
@@ -12,7 +13,7 @@ use {
 #[test]
 fn test_key_agreement() {
     let params = JubjubBls12::new();
-    let mut rng = OsRng::new().unwrap();
+    let mut rng = OsRng;
 
     // Create random viewing key
     let vk = ViewingKey::<Bls12> {
@@ -22,7 +23,9 @@ fn test_key_agreement() {
 
     // Create a random address with the viewing key
     let addr = loop {
-        match vk.into_payment_address(Diversifier(rng.gen()), &params) {
+        let mut d = [0; 11];
+        rng.fill_bytes(&mut d);
+        match vk.into_payment_address(Diversifier(d), &params) {
             Some(a) => break a,
             None => {}
         }

librustzcash/src/tests/key_components.rs

@@ -1,5 +1,6 @@
-use pairing::{bls12_381::Bls12, PrimeField, PrimeFieldRepr};
+use ff::{PrimeField, PrimeFieldRepr};
-use sapling_crypto::{
+use pairing::bls12_381::Bls12;
+use zcash_primitives::{
     jubjub::{fs::FsRepr, FixedGenerators, JubjubEngine, JubjubParams},
     primitives::{Diversifier, ProofGenerationKey},
 };
@@ -27,6 +28,8 @@ fn key_components() {
         note_v: u64,
         note_r: [u8; 32],
         note_cm: [u8; 32],
+        note_pos: u64,
+        note_nf: [u8; 32],
     };
 
     // From https://github.com/zcash-hackworks/zcash-test-vectors/blob/master/sapling_key_components.py
@@ -86,6 +89,12 @@ fn key_components() {
                 0x18, 0x50, 0xc9, 0xfe, 0xd4, 0x4f, 0xce, 0x08, 0x06, 0x27, 0x8f, 0x08, 0x3e, 0xf2,
                 0xdd, 0x07, 0x64, 0x39,
             ],
+            note_pos: 0,
+            note_nf: [
+                0x44, 0xfa, 0xd6, 0x56, 0x4f, 0xfd, 0xec, 0x9f, 0xa1, 0x9c, 0x43, 0xa2, 0x8f, 0x86,
+                0x1d, 0x5e, 0xbf, 0x60, 0x23, 0x46, 0x00, 0x7d, 0xe7, 0x62, 0x67, 0xd9, 0x75, 0x27,
+                0x47, 0xab, 0x40, 0x63,
+            ],
         },
         TestVector {
             sk: [
@@ -142,6 +151,12 @@ fn key_components() {
                 0x89, 0xe1, 0x0e, 0x26, 0x6b, 0xcf, 0xa3, 0x1c, 0x31, 0xb2, 0x9a, 0x53, 0xae, 0x72,
                 0xca, 0xd4, 0x69, 0x50,
             ],
+            note_pos: 763714296,
+            note_nf: [
+                0x67, 0x9e, 0xb0, 0xc3, 0xa7, 0x57, 0xe2, 0xae, 0x83, 0xcd, 0xb4, 0x2a, 0x1a, 0xb2,
+                0x59, 0xd7, 0x83, 0x88, 0x31, 0x54, 0x19, 0xad, 0xc7, 0x1d, 0x2e, 0x37, 0x63, 0x17,
+                0x4c, 0x2e, 0x9d, 0x93,
+            ],
         },
         TestVector {
             sk: [
@@ -198,6 +213,12 @@ fn key_components() {
                 0xb7, 0x40, 0x82, 0x96, 0x66, 0x17, 0x70, 0xb1, 0x01, 0xb0, 0xaa, 0x87, 0x83, 0x9f,
                 0x4e, 0x55, 0xf1, 0x51,
             ],
+            note_pos: 1527428592,
+            note_nf: [
+                0xe9, 0x8f, 0x6a, 0x8f, 0x34, 0xff, 0x49, 0x80, 0x59, 0xb3, 0xc7, 0x31, 0xb9, 0x1f,
+                0x45, 0x11, 0x08, 0xc4, 0x95, 0x4d, 0x91, 0x94, 0x84, 0x36, 0x1c, 0xf9, 0xb4, 0x8f,
+                0x59, 0xae, 0x1d, 0x14,
+            ],
         },
         TestVector {
             sk: [
@@ -254,6 +275,12 @@ fn key_components() {
                 0xbd, 0x10, 0x5d, 0x88, 0x39, 0x21, 0x2e, 0x0d, 0x16, 0x44, 0xb9, 0xd5, 0x5c, 0xaa,
                 0x60, 0xd1, 0x9b, 0x6c,
             ],
+            note_pos: 2291142888,
+            note_nf: [
+                0x55, 0x47, 0xaa, 0x12, 0xff, 0x80, 0xa6, 0xb3, 0x30, 0x4e, 0x3b, 0x05, 0x86, 0x56,
+                0x47, 0x2a, 0xbd, 0x2c, 0x81, 0x83, 0xb5, 0x9d, 0x07, 0x37, 0xb9, 0x3c, 0xee, 0x75,
+                0x8b, 0xec, 0x47, 0xa1,
+            ],
         },
         TestVector {
             sk: [
@@ -310,6 +337,12 @@ fn key_components() {
                 0xcf, 0x1e, 0x67, 0x15, 0xbf, 0xe7, 0x0b, 0x63, 0x2d, 0x04, 0x4b, 0x26, 0xfb, 0x2b,
                 0xc7, 0x1b, 0x7f, 0x36,
             ],
+            note_pos: 3054857184,
+            note_nf: [
+                0x8a, 0x9a, 0xbd, 0xa3, 0xd4, 0xef, 0x85, 0xca, 0xf2, 0x2b, 0xfa, 0xf2, 0xc4, 0x8f,
+                0x62, 0x38, 0x2a, 0x73, 0xa1, 0x62, 0x4e, 0xb8, 0xeb, 0x2b, 0xd0, 0x0d, 0x27, 0x03,
+                0x01, 0xbf, 0x3d, 0x13,
+            ],
         },
         TestVector {
             sk: [
@@ -366,6 +399,12 @@ fn key_components() {
                 0x1d, 0x74, 0xc5, 0xbc, 0xf2, 0xe1, 0xef, 0x95, 0x66, 0x90, 0x44, 0x73, 0x01, 0x69,
                 0xde, 0x1a, 0x5b, 0x4c,
             ],
+            note_pos: 3818571480,
+            note_nf: [
+                0x33, 0x2a, 0xd9, 0x9e, 0xb9, 0xe9, 0x77, 0xeb, 0x62, 0x7a, 0x12, 0x2d, 0xbf, 0xb2,
+                0xf2, 0x5f, 0xe5, 0x88, 0xe5, 0x97, 0x75, 0x3e, 0xc5, 0x58, 0x0f, 0xf2, 0xbe, 0x20,
+                0xb6, 0xc9, 0xa7, 0xe1,
+            ],
         },
         TestVector {
             sk: [
@@ -422,6 +461,12 @@ fn key_components() {
                 0x90, 0xb6, 0xe0, 0xf2, 0xf4, 0xbf, 0x4e, 0xc4, 0xa0, 0xdb, 0x5b, 0xbc, 0xcb, 0x5b,
                 0x78, 0x3a, 0x1e, 0x55,
             ],
+            note_pos: 287318480,
+            note_nf: [
+                0xfc, 0x74, 0xcd, 0x0e, 0x4b, 0xe0, 0x49, 0x57, 0xb1, 0x96, 0xcf, 0x87, 0x34, 0xae,
+                0x99, 0x23, 0x96, 0xaf, 0x4c, 0xfa, 0x8f, 0xec, 0xbb, 0x86, 0xf9, 0x61, 0xe6, 0xb4,
+                0x07, 0xd5, 0x1e, 0x11,
+            ],
         },
         TestVector {
             sk: [
@@ -478,6 +523,12 @@ fn key_components() {
                 0x60, 0xa0, 0x06, 0xf8, 0x2b, 0xb7, 0xad, 0xcd, 0x75, 0x22, 0x3f, 0xa8, 0x59, 0x36,
                 0xf7, 0x8c, 0x2b, 0x23,
             ],
+            note_pos: 1051032776,
+            note_nf: [
+                0xd2, 0xe8, 0x87, 0xbd, 0x85, 0x4a, 0x80, 0x2b, 0xce, 0x85, 0x70, 0x53, 0x02, 0x0f,
+                0x5d, 0x3e, 0x7c, 0x8a, 0xe5, 0x26, 0x7c, 0x5b, 0x65, 0x83, 0xb3, 0xd2, 0x12, 0xcc,
+                0x8b, 0xb6, 0x98, 0x90,
+            ],
         },
         TestVector {
             sk: [
@@ -534,6 +585,12 @@ fn key_components() {
                 0x23, 0x36, 0xc2, 0xa0, 0x5a, 0x08, 0x03, 0x23, 0x9b, 0x5b, 0x88, 0xfd, 0x92, 0x07,
                 0x8f, 0xea, 0x4d, 0x04,
             ],
+            note_pos: 1814747072,
+            note_nf: [
+                0xa8, 0x2f, 0x17, 0x50, 0xcc, 0x5b, 0x2b, 0xee, 0x64, 0x9a, 0x36, 0x5c, 0x04, 0x20,
+                0xed, 0x87, 0x07, 0x5b, 0x88, 0x71, 0xfd, 0xa4, 0xa7, 0xf5, 0x84, 0x0d, 0x6b, 0xbe,
+                0xb1, 0x7c, 0xd6, 0x20,
+            ],
         },
         TestVector {
             sk: [
@@ -590,6 +647,12 @@ fn key_components() {
                 0x64, 0x41, 0x9b, 0x0e, 0x55, 0x0a, 0xbb, 0xcb, 0x8e, 0x2b, 0xcb, 0xda, 0x8b, 0x63,
                 0xe4, 0x1d, 0xeb, 0x37,
             ],
+            note_pos: 2578461368,
+            note_nf: [
+                0x65, 0x36, 0x74, 0x87, 0x3b, 0x3c, 0x67, 0x0c, 0x58, 0x85, 0x84, 0x73, 0xe7, 0xfe,
+                0x72, 0x19, 0x72, 0xfb, 0x96, 0xe2, 0x15, 0xb8, 0x73, 0x77, 0xa1, 0x7c, 0xa3, 0x71,
+                0x0d, 0x93, 0xc9, 0xe9,
+            ],
         },
     ];
 
@@ -662,5 +725,7 @@ fn key_components() {
             note.cm(&JUBJUB).into_repr().write_le(&mut vec).unwrap();
             assert_eq!(&vec, &tv.note_cm);
         }
+
+        assert_eq!(note.nf(&fvk, tv.note_pos, &JUBJUB), tv.note_nf);
     }
 }

librustzcash/src/tests/mod.rs

@@ -1,4 +1,4 @@
-use sapling_crypto::jubjub::{FixedGenerators, JubjubParams};
+use zcash_primitives::jubjub::{FixedGenerators, JubjubParams};
 
 use super::JUBJUB;
 

librustzcash/src/tests/signatures.rs

@@ -1,7 +1,7 @@
-use pairing::{bls12_381::Bls12, PrimeField, PrimeFieldRepr};
+use ff::{PrimeField, PrimeFieldRepr};
-use sapling_crypto::{
+use pairing::bls12_381::Bls12;
-    jubjub::{FixedGenerators, JubjubEngine}, redjubjub::{PrivateKey, PublicKey, Signature},
+use zcash_primitives::jubjub::{FixedGenerators, JubjubEngine};
-};
+use zcash_primitives::redjubjub::{PrivateKey, PublicKey, Signature};
 
 use super::JUBJUB;
 

pairing/Cargo.toml

@@ -3,7 +3,10 @@ name = "pairing"
 
 # Remember to change version string in README.md.
 version = "0.14.2"
-authors = ["Sean Bowe <ewillbefull@gmail.com>"]
+authors = [
+    "Sean Bowe <ewillbefull@gmail.com>",
+    "Jack Grigg <jack@z.cash>",
+]
 license = "MIT/Apache-2.0"
 
 description = "Pairing-friendly elliptic curve library"
@@ -12,12 +15,15 @@ homepage = "https://github.com/ebfull/pairing"
 repository = "https://github.com/ebfull/pairing"
 
 [dependencies]
-rand = "0.4"
 byteorder = "1"
-clippy = { version = "0.0.200", optional = true }
+ff = { path = "../ff", features = ["derive"] }
+group = { path = "../group" }
+rand_core = "0.5"
+
+[dev-dependencies]
+rand_xorshift = "0.2"
 
 [features]
 unstable-features = ["expose-arith"]
 expose-arith = []
-u128-support = []
 default = []

pairing/README.md

@@ -6,14 +6,6 @@ This is a Rust crate for using pairing-friendly elliptic curves. Currently, only
 
 Bring the `pairing` crate into your project just as you normally would.
 
-If you're using a supported platform and the nightly Rust compiler, you can enable the `u128-support` feature for faster arithmetic.
-
-```toml
-[dependencies.pairing]
-version = "0.14"
-features = ["u128-support"]
-```
-
 ## Security Warnings
 
 This library does not make any guarantees about constant-time operations, memory access patterns, or resistance to side-channel attacks.

pairing/benches/bls12_381/ec.rs

@@ -1,8 +1,8 @@
 mod g1 {
     use rand::{Rand, SeedableRng, XorShiftRng};
 
+    use group::CurveProjective;
     use pairing::bls12_381::*;
-    use pairing::CurveProjective;
 
     #[bench]
     fn bench_g1_mul_assign(b: &mut ::test::Bencher) {
@@ -65,8 +65,8 @@ mod g1 {
 mod g2 {
     use rand::{Rand, SeedableRng, XorShiftRng};
 
+    use group::CurveProjective;
     use pairing::bls12_381::*;
-    use pairing::CurveProjective;
 
     #[bench]
     fn bench_g2_mul_assign(b: &mut ::test::Bencher) {

pairing/benches/bls12_381/fq.rs

@@ -1,7 +1,7 @@
 use rand::{Rand, SeedableRng, XorShiftRng};
 
+use ff::{Field, PrimeField, PrimeFieldRepr, SqrtField};
 use pairing::bls12_381::*;
-use pairing::{Field, PrimeField, PrimeFieldRepr, SqrtField};
 
 #[bench]
 fn bench_fq_repr_add_nocarry(b: &mut ::test::Bencher) {

pairing/benches/bls12_381/fq12.rs

@@ -1,7 +1,7 @@
 use rand::{Rand, SeedableRng, XorShiftRng};
 
+use ff::Field;
 use pairing::bls12_381::*;
-use pairing::Field;
 
 #[bench]
 fn bench_fq12_add_assign(b: &mut ::test::Bencher) {

pairing/benches/bls12_381/fq2.rs

@@ -1,7 +1,7 @@
 use rand::{Rand, SeedableRng, XorShiftRng};
 
+use ff::{Field, SqrtField};
 use pairing::bls12_381::*;
-use pairing::{Field, SqrtField};
 
 #[bench]
 fn bench_fq2_add_assign(b: &mut ::test::Bencher) {

pairing/benches/bls12_381/fr.rs

@@ -1,7 +1,7 @@
 use rand::{Rand, SeedableRng, XorShiftRng};
 
+use ff::{Field, PrimeField, PrimeFieldRepr, SqrtField};
 use pairing::bls12_381::*;
-use pairing::{Field, PrimeField, PrimeFieldRepr, SqrtField};
 
 #[bench]
 fn bench_fr_repr_add_nocarry(b: &mut ::test::Bencher) {

pairing/benches/bls12_381/mod.rs

@@ -7,7 +7,7 @@ mod fr;
 use rand::{Rand, SeedableRng, XorShiftRng};
 
 use pairing::bls12_381::*;
-use pairing::{CurveAffine, Engine};
+use pairing::{Engine, PairingCurveAffine};
 
 #[bench]
 fn bench_pairing_g1_preparation(b: &mut ::test::Bencher) {

pairing/benches/pairing_benches.rs

@@ -1,5 +1,7 @@
 #![feature(test)]
 
+extern crate ff;
+extern crate group;
 extern crate pairing;
 extern crate rand;
 extern crate test;

pairing/src/bls12_381/ec.rs

@@ -14,11 +14,10 @@ macro_rules! curve_impl {
         pub struct $affine {
             pub(crate) x: $basefield,
             pub(crate) y: $basefield,
-            pub(crate) infinity: bool
+            pub(crate) infinity: bool,
         }
 
-        impl ::std::fmt::Display for $affine
+        impl ::std::fmt::Display for $affine {
-        {
             fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
                 if self.infinity {
                     write!(f, "{}(Infinity)", $name)
@@ -30,13 +29,12 @@ macro_rules! curve_impl {
 
         #[derive(Copy, Clone, Debug, Eq)]
         pub struct $projective {
-           pub(crate) x: $basefield,
+            pub(crate) x: $basefield,
-           pub(crate) y: $basefield,
+            pub(crate) y: $basefield,
-           pub(crate) z: $basefield
+            pub(crate) z: $basefield,
         }
 
-        impl ::std::fmt::Display for $projective
+        impl ::std::fmt::Display for $projective {
-        {
             fn fmt(&self, f: &mut ::std::fmt::Formatter) -> ::std::fmt::Result {
                 write!(f, "{}", self.into_affine())
             }
@@ -89,7 +87,9 @@ macro_rules! curve_impl {
                 let mut res = $projective::zero();
                 for i in bits {
                     res.double();
-                    if i { res.add_assign_mixed(self) }
+                    if i {
+                        res.add_assign_mixed(self)
+                    }
                 }
                 res
             }
@@ -112,12 +112,8 @@ macro_rules! curve_impl {
 
                     $affine {
                         x: x,
-                        y: if (y < negy) ^ greatest {
+                        y: if (y < negy) ^ greatest { y } else { negy },
-                            y
+                        infinity: false,
-                        } else {
-                            negy
-                        },
-                        infinity: false
                     }
                 })
             }
@@ -148,18 +144,15 @@ macro_rules! curve_impl {
             type Engine = Bls12;
             type Scalar = $scalarfield;
             type Base = $basefield;
-            type Prepared = $prepared;
             type Projective = $projective;
             type Uncompressed = $uncompressed;
             type Compressed = $compressed;
-            type Pair = $pairing;
-            type PairingResult = Fq12;
 
             fn zero() -> Self {
                 $affine {
                     x: $basefield::zero(),
                     y: $basefield::one(),
-                    infinity: true
+                    infinity: true,
                 }
             }
 
@@ -182,6 +175,16 @@ macro_rules! curve_impl {
                 }
             }
 
+            fn into_projective(&self) -> $projective {
+                (*self).into()
+            }
+        }
+
+        impl PairingCurveAffine for $affine {
+            type Prepared = $prepared;
+            type Pair = $pairing;
+            type PairingResult = Fq12;
+
             fn prepare(&self) -> Self::Prepared {
                 $prepared::from_affine(*self)
             }
@@ -189,18 +192,18 @@ macro_rules! curve_impl {
             fn pairing_with(&self, other: &Self::Pair) -> Self::PairingResult {
                 self.perform_pairing(other)
             }
-
-            fn into_projective(&self) -> $projective {
-                (*self).into()
-            }
-
         }
 
-        impl Rand for $projective {
+        impl CurveProjective for $projective {
-            fn rand<R: Rng>(rng: &mut R) -> Self {
+            type Engine = Bls12;
+            type Scalar = $scalarfield;
+            type Base = $basefield;
+            type Affine = $affine;
+
+            fn random<R: RngCore>(rng: &mut R) -> Self {
                 loop {
-                    let x = rng.gen();
+                    let x = $basefield::random(rng);
-                    let greatest = rng.gen();
+                    let greatest = rng.next_u32() % 2 != 0;
 
                     if let Some(p) = $affine::get_point_from_x(x, greatest) {
                         let p = p.scale_by_cofactor();
@@ -211,13 +214,6 @@ macro_rules! curve_impl {
                     }
                 }
             }
-        }
-
-        impl CurveProjective for $projective {
-            type Engine = Bls12;
-            type Scalar = $scalarfield;
-            type Base = $basefield;
-            type Affine = $affine;
 
             // The point at infinity is always represented by
             // Z = 0.
@@ -225,7 +221,7 @@ macro_rules! curve_impl {
                 $projective {
                     x: $basefield::zero(),
                     y: $basefield::one(),
-                    z: $basefield::zero()
+                    z: $basefield::zero(),
                 }
             }
 
@@ -243,8 +239,7 @@ macro_rules! curve_impl {
                 self.is_zero() || self.z == $basefield::one()
             }
 
-            fn batch_normalization(v: &mut [Self])
+            fn batch_normalization(v: &mut [Self]) {
-            {
                 // Montgomery’s Trick and Fast Implementation of Masked AES
                 // Genelle, Prouff and Quisquater
                 // Section 3.2
@@ -252,9 +247,10 @@ macro_rules! curve_impl {
                 // First pass: compute [a, ab, abc, ...]
                 let mut prod = Vec::with_capacity(v.len());
                 let mut tmp = $basefield::one();
-                for g in v.iter_mut()
+                for g in v
-                          // Ignore normalized elements
+                    .iter_mut()
-                          .filter(|g| !g.is_normalized())
+                    // Ignore normalized elements
+                    .filter(|g| !g.is_normalized())
                 {
                     tmp.mul_assign(&g.z);
                     prod.push(tmp);
@@ -264,13 +260,19 @@ macro_rules! curve_impl {
                 tmp = tmp.inverse().unwrap(); // Guaranteed to be nonzero.
 
                 // Second pass: iterate backwards to compute inverses
-                for (g, s) in v.iter_mut()
+                for (g, s) in v
-                               // Backwards
+                    .iter_mut()
-                               .rev()
+                    // Backwards
-                               // Ignore normalized elements
+                    .rev()
-                               .filter(|g| !g.is_normalized())
+                    // Ignore normalized elements
-                               // Backwards, skip last element, fill in one for last term.
+                    .filter(|g| !g.is_normalized())
-                               .zip(prod.into_iter().rev().skip(1).chain(Some($basefield::one())))
+                    // Backwards, skip last element, fill in one for last term.
+                    .zip(
+                        prod.into_iter()
+                            .rev()
+                            .skip(1)
+                            .chain(Some($basefield::one())),
+                    )
                 {
                     // tmp := tmp * g.z; g.z := tmp * s = 1/z
                     let mut newtmp = tmp;
@@ -281,9 +283,7 @@ macro_rules! curve_impl {
                 }
 
                 // Perform affine transformations
-                for g in v.iter_mut()
+                for g in v.iter_mut().filter(|g| !g.is_normalized()) {
-                          .filter(|g| !g.is_normalized())
-                {
                     let mut z = g.z; // 1/z
                     z.square(); // 1/z^2
                     g.x.mul_assign(&z); // x/z^2
@@ -536,8 +536,7 @@ macro_rules! curve_impl {
 
                 let mut found_one = false;
 
-                for i in BitIterator::new(other.into())
+                for i in BitIterator::new(other.into()) {
-                {
                     if found_one {
                         res.double();
                     } else {
@@ -575,7 +574,7 @@ macro_rules! curve_impl {
                     $projective {
                         x: p.x,
                         y: p.y,
-                        z: $basefield::one()
+                        z: $basefield::one(),
                     }
                 }
             }
@@ -592,7 +591,7 @@ macro_rules! curve_impl {
                     $affine {
                         x: p.x,
                         y: p.y,
-                        infinity: false
+                        infinity: false,
                     }
                 } else {
                     // Z is nonzero, so it must have an inverse in a field.
@@ -612,23 +611,22 @@ macro_rules! curve_impl {
                     $affine {
                         x: x,
                         y: y,
-                        infinity: false
+                        infinity: false,
                     }
                 }
             }
         }
-    }
+    };
 }
 
 pub mod g1 {
     use super::super::{Bls12, Fq, Fq12, FqRepr, Fr, FrRepr};
     use super::g2::G2Affine;
-    use rand::{Rand, Rng};
+    use ff::{BitIterator, Field, PrimeField, PrimeFieldRepr, SqrtField};
+    use group::{CurveAffine, CurveProjective, EncodedPoint, GroupDecodingError};
+    use rand_core::RngCore;
     use std::fmt;
-    use {
+    use {Engine, PairingCurveAffine};
-        BitIterator, CurveAffine, CurveProjective, EncodedPoint, Engine, Field, GroupDecodingError,
-        PrimeField, PrimeFieldRepr, SqrtField,
-    };
 
     curve_impl!(
         "G1",
@@ -954,7 +952,7 @@ pub mod g1 {
                 let negyrepr = negy.into_repr();
 
                 let p = G1Affine {
-                    x: x,
+                    x,
                     y: if yrepr < negyrepr { y } else { negy },
                     infinity: false,
                 };
@@ -989,7 +987,8 @@ pub mod g1 {
                     0x9fe83b1b4a5d648d,
                     0xf583cc5a508f6a40,
                     0xc3ad2aefde0bb13,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 y: Fq::from_repr(FqRepr([
                     0x60aa6f9552f03aae,
                     0xecd01d5181300d35,
@@ -997,7 +996,8 @@ pub mod g1 {
                     0xe760f57922998c9d,
                     0x953703f5795a39e5,
                     0xfe3ae0922df702c,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 infinity: false,
             };
             assert!(!p.is_on_curve());
@@ -1014,7 +1014,8 @@ pub mod g1 {
                     0xea034ee2928b30a8,
                     0xbd8833dc7c79a7f7,
                     0xe45c9f0c0438675,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 y: Fq::from_repr(FqRepr([
                     0x3b450eb1ab7b5dad,
                     0xa65cb81e975e8675,
@@ -1022,7 +1023,8 @@ pub mod g1 {
                     0x753ddf21a2601d20,
                     0x532d0b640bd3ff8b,
                     0x118d2c543f031102,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 infinity: false,
             };
             assert!(!p.is_on_curve());
@@ -1040,7 +1042,8 @@ pub mod g1 {
                     0xf35de9ce0d6b4e84,
                     0x265bddd23d1dec54,
                     0x12a8778088458308,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 y: Fq::from_repr(FqRepr([
                     0x8a22defa0d526256,
                     0xc57ca55456fcb9ae,
@@ -1048,7 +1051,8 @@ pub mod g1 {
                     0x921beef89d4f29df,
                     0x5b6fda44ad85fa78,
                     0xed74ab9f302cbe0,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 infinity: false,
             };
             assert!(p.is_on_curve());
@@ -1066,7 +1070,8 @@ pub mod g1 {
                 0x485e77d50a5df10d,
                 0x4c6fcac4b55fd479,
                 0x86ed4d9906fb064,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             y: Fq::from_repr(FqRepr([
                 0xd25ee6461538c65,
                 0x9f3bbb2ecd3719b9,
@@ -1074,7 +1079,8 @@ pub mod g1 {
                 0xcefca68333c35288,
                 0x570c8005f8573fa6,
                 0x152ca696fe034442,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             z: Fq::one(),
         };
 
@@ -1086,7 +1092,8 @@ pub mod g1 {
                 0x5f44314ec5e3fb03,
                 0x24e8538737c6e675,
                 0x8abd623a594fba8,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             y: Fq::from_repr(FqRepr([
                 0x6b0528f088bb7044,
                 0x2fdeb5c82917ff9e,
@@ -1094,7 +1101,8 @@ pub mod g1 {
                 0xd65104c6f95a872a,
                 0x1f2998a5a9c61253,
                 0xe74846154a9e44,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             z: Fq::one(),
         });
 
@@ -1110,7 +1118,8 @@ pub mod g1 {
                     0xc4f9a52a428e23bb,
                     0xd178b28dd4f407ef,
                     0x17fb8905e9183c69
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 y: Fq::from_repr(FqRepr([
                     0xd0de9d65292b7710,
                     0xf6a05f2bcf1d9ca7,
@@ -1118,7 +1127,8 @@ pub mod g1 {
                     0xeec8d1a5b7466c58,
                     0x4bc362649dce6376,
                     0x430cbdc5455b00a
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 infinity: false,
             }
         );
@@ -1134,7 +1144,8 @@ pub mod g1 {
                 0x485e77d50a5df10d,
                 0x4c6fcac4b55fd479,
                 0x86ed4d9906fb064,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             y: Fq::from_repr(FqRepr([
                 0xd25ee6461538c65,
                 0x9f3bbb2ecd3719b9,
@@ -1142,7 +1153,8 @@ pub mod g1 {
                 0xcefca68333c35288,
                 0x570c8005f8573fa6,
                 0x152ca696fe034442,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             z: Fq::one(),
         };
 
@@ -1160,7 +1172,8 @@ pub mod g1 {
                     0x4b914c16687dcde0,
                     0x66c8baf177d20533,
                     0xaf960cff3d83833
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 y: Fq::from_repr(FqRepr([
                     0x3f0675695f5177a8,
                     0x2b6d82ae178a1ba0,
@@ -1168,7 +1181,8 @@ pub mod g1 {
                     0x1771a65b60572f4e,
                     0x8b547c1313b27555,
                     0x135075589a687b1e
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 infinity: false,
             }
         );
@@ -1191,7 +1205,8 @@ pub mod g1 {
                 0x71ffa8021531705,
                 0x7418d484386d267,
                 0xd5108d8ff1fbd6,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             y: Fq::from_repr(FqRepr([
                 0xa776ccbfe9981766,
                 0x255632964ff40f4a,
@@ -1199,7 +1214,8 @@ pub mod g1 {
                 0x520f74773e74c8c3,
                 0x484c8fc982008f0,
                 0xee2c3d922008cc6,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             infinity: false,
         };
 
@@ -1211,7 +1227,8 @@ pub mod g1 {
                 0xc6e05201e5f83991,
                 0xf7c75910816f207c,
                 0x18d4043e78103106,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             y: Fq::from_repr(FqRepr([
                 0xa776ccbfe9981766,
                 0x255632964ff40f4a,
@@ -1219,7 +1236,8 @@ pub mod g1 {
                 0x520f74773e74c8c3,
                 0x484c8fc982008f0,
                 0xee2c3d922008cc6,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             infinity: false,
         };
 
@@ -1234,7 +1252,8 @@ pub mod g1 {
                 0x9676ff02ec39c227,
                 0x4c12c15d7e55b9f3,
                 0x57fd1e317db9bd,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             y: Fq::from_repr(FqRepr([
                 0x1288334016679345,
                 0xf955cd68615ff0b5,
@@ -1242,7 +1261,8 @@ pub mod g1 {
                 0x1267d70db51049fb,
                 0x4696deb9ab2ba3e7,
                 0xb1e4e11177f59d4,
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             infinity: false,
         };
 
@@ -1263,19 +1283,19 @@ pub mod g1 {
 
     #[test]
     fn g1_curve_tests() {
-        ::tests::curve::curve_tests::<G1>();
+        use group::tests::curve_tests;
+        curve_tests::<G1>();
     }
 }
 
 pub mod g2 {
     use super::super::{Bls12, Fq, Fq12, Fq2, FqRepr, Fr, FrRepr};
     use super::g1::G1Affine;
-    use rand::{Rand, Rng};
+    use ff::{BitIterator, Field, PrimeField, PrimeFieldRepr, SqrtField};
+    use group::{CurveAffine, CurveProjective, EncodedPoint, GroupDecodingError};
+    use rand_core::RngCore;
     use std::fmt;
-    use {
+    use {Engine, PairingCurveAffine};
-        BitIterator, CurveAffine, CurveProjective, EncodedPoint, Engine, Field, GroupDecodingError,
-        PrimeField, PrimeFieldRepr, SqrtField,
-    };
 
     curve_impl!(
         "G2",
@@ -1636,7 +1656,7 @@ pub mod g2 {
                 negy.negate();
 
                 let p = G2Affine {
-                    x: x,
+                    x,
                     y: if y < negy { y } else { negy },
                     infinity: false,
                 };
@@ -1672,7 +1692,8 @@ pub mod g2 {
                         0x7a17a004747e3dbe,
                         0xcc65406a7c2e5a73,
                         0x10b8c03d64db4d0c,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0xd30e70fe2f029778,
                         0xda30772df0f5212e,
@@ -1680,7 +1701,8 @@ pub mod g2 {
                         0xfb777e5b9b568608,
                         0x789bac1fec71a2b9,
                         0x1342f02e2da54405,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 y: Fq2 {
                     c0: Fq::from_repr(FqRepr([
@@ -1690,7 +1712,8 @@ pub mod g2 {
                         0x663015d9410eb608,
                         0x78e82a79d829a544,
                         0x40a00545bb3c1e,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0x4709802348e79377,
                         0xb5ac4dc9204bcfbd,
@@ -1698,7 +1721,8 @@ pub mod g2 {
                         0x15008b1dc399e8df,
                         0x68128fd0548a3829,
                         0x16a613db5c873aaa,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 infinity: false,
             };
@@ -1717,7 +1741,8 @@ pub mod g2 {
                         0x41abba710d6c692c,
                         0xffcc4b2b62ce8484,
                         0x6993ec01b8934ed,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0xb94e92d5f874e26,
                         0x44516408bc115d95,
@@ -1725,7 +1750,8 @@ pub mod g2 {
                         0xa5a0c2b7131f3555,
                         0x83800965822367e7,
                         0x10cf1d3ad8d90bfa,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 y: Fq2 {
                     c0: Fq::from_repr(FqRepr([
@@ -1735,7 +1761,8 @@ pub mod g2 {
                         0x5a9171720e73eb51,
                         0x38eb4fd8d658adb7,
                         0xb649051bbc1164d,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0x9225814253d7df75,
                         0xc196c2513477f887,
@@ -1743,7 +1770,8 @@ pub mod g2 {
                         0x55f2b8efad953e04,
                         0x7379345eda55265e,
                         0x377f2e6208fd4cb,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 infinity: false,
             };
@@ -1763,7 +1791,8 @@ pub mod g2 {
                         0x2199bc19c48c393d,
                         0x4a151b732a6075bf,
                         0x17762a3b9108c4a7,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0x26f461e944bbd3d1,
                         0x298f3189a9cf6ed6,
@@ -1771,7 +1800,8 @@ pub mod g2 {
                         0x7e147f3f9e6e241,
                         0x72a9b63583963fff,
                         0x158b0083c000462,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 y: Fq2 {
                     c0: Fq::from_repr(FqRepr([
@@ -1781,7 +1811,8 @@ pub mod g2 {
                         0x68cad19430706b4d,
                         0x3ccfb97b924dcea8,
                         0x1660f93434588f8d,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0xaaed3985b6dcb9c7,
                         0xc1e985d6d898d9f4,
@@ -1789,7 +1820,8 @@ pub mod g2 {
                         0x3940a2dbb914b529,
                         0xbeb88137cf34f3e7,
                         0x1699ee577c61b694,
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 infinity: false,
             };
@@ -1809,7 +1841,8 @@ pub mod g2 {
                     0x72556c999f3707ac,
                     0x4617f2e6774e9711,
                     0x100b2fe5bffe030b,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 c1: Fq::from_repr(FqRepr([
                     0x7a33555977ec608,
                     0xe23039d1fe9c0881,
@@ -1817,7 +1850,8 @@ pub mod g2 {
                     0x4637c4f417667e2e,
                     0x93ebe7c3e41f6acc,
                     0xde884f89a9a371b,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
             },
             y: Fq2 {
                 c0: Fq::from_repr(FqRepr([
@@ -1827,7 +1861,8 @@ pub mod g2 {
                     0x25fd427b4122f231,
                     0xd83112aace35cae,
                     0x191b2432407cbb7f,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 c1: Fq::from_repr(FqRepr([
                     0xf68ae82fe97662f5,
                     0xe986057068b50b7d,
@@ -1835,7 +1870,8 @@ pub mod g2 {
                     0x9eaa6d19de569196,
                     0xf6a03d31e2ec2183,
                     0x3bdafaf7ca9b39b,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
             },
             z: Fq2::one(),
         };
@@ -1849,7 +1885,8 @@ pub mod g2 {
                     0x8e73a96b329ad190,
                     0x27c546f75ee1f3ab,
                     0xa33d27add5e7e82,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 c1: Fq::from_repr(FqRepr([
                     0x93b1ebcd54870dfe,
                     0xf1578300e1342e11,
@@ -1857,7 +1894,8 @@ pub mod g2 {
                     0x2089faf462438296,
                     0x828e5848cd48ea66,
                     0x141ecbac1deb038b,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
             },
             y: Fq2 {
                 c0: Fq::from_repr(FqRepr([
@@ -1867,7 +1905,8 @@ pub mod g2 {
                     0x2767032fc37cc31d,
                     0xd5ee2aba84fd10fe,
                     0x16576ccd3dd0a4e8,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 c1: Fq::from_repr(FqRepr([
                     0x4da9b6f6a96d1dd2,
                     0x9657f7da77f1650e,
@@ -1875,7 +1914,8 @@ pub mod g2 {
                     0x31898db63f87363a,
                     0xabab040ddbd097cc,
                     0x11ad236b9ba02990,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
             },
             z: Fq2::one(),
         });
@@ -1893,7 +1933,8 @@ pub mod g2 {
                         0xf1273e6406eef9cc,
                         0xababd760ff05cb92,
                         0xd7c20456617e89
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0xd1a50b8572cbd2b8,
                         0x238f0ac6119d07df,
@@ -1901,7 +1942,8 @@ pub mod g2 {
                         0x8b203284c51edf6b,
                         0xc8a0b730bbb21f5e,
                         0x1a3b59d29a31274
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 y: Fq2 {
                     c0: Fq::from_repr(FqRepr([
@@ -1911,7 +1953,8 @@ pub mod g2 {
                         0x64528ab3863633dc,
                         0x159384333d7cba97,
                         0x4cb84741f3cafe8
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0x242af0dc3640e1a4,
                         0xe90a73ad65c66919,
@@ -1919,7 +1962,8 @@ pub mod g2 {
                         0x38528f92b689644d,
                         0xb6884deec59fb21f,
                         0x3c075d3ec52ba90
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 infinity: false,
             }
@@ -1937,7 +1981,8 @@ pub mod g2 {
                     0x72556c999f3707ac,
                     0x4617f2e6774e9711,
                     0x100b2fe5bffe030b,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 c1: Fq::from_repr(FqRepr([
                     0x7a33555977ec608,
                     0xe23039d1fe9c0881,
@@ -1945,7 +1990,8 @@ pub mod g2 {
                     0x4637c4f417667e2e,
                     0x93ebe7c3e41f6acc,
                     0xde884f89a9a371b,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
             },
             y: Fq2 {
                 c0: Fq::from_repr(FqRepr([
@@ -1955,7 +2001,8 @@ pub mod g2 {
                     0x25fd427b4122f231,
                     0xd83112aace35cae,
                     0x191b2432407cbb7f,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
                 c1: Fq::from_repr(FqRepr([
                     0xf68ae82fe97662f5,
                     0xe986057068b50b7d,
@@ -1963,7 +2010,8 @@ pub mod g2 {
                     0x9eaa6d19de569196,
                     0xf6a03d31e2ec2183,
                     0x3bdafaf7ca9b39b,
-                ])).unwrap(),
+                ]))
+                .unwrap(),
             },
             z: Fq2::one(),
         };
@@ -1983,7 +2031,8 @@ pub mod g2 {
                         0xbcedcfce1e52d986,
                         0x9755d4a3926e9862,
                         0x18bab73760fd8024
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0x4e7c5e0a2ae5b99e,
                         0x96e582a27f028961,
@@ -1991,7 +2040,8 @@ pub mod g2 {
                         0xeb0cf5e610ef4fe7,
                         0x7b4c2bae8db6e70b,
                         0xf136e43909fca0
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 y: Fq2 {
                     c0: Fq::from_repr(FqRepr([
@@ -2001,7 +2051,8 @@ pub mod g2 {
                         0xa5a2a51f7fde787b,
                         0x8b92866bc6384188,
                         0x81a53fe531d64ef
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                     c1: Fq::from_repr(FqRepr([
                         0x4c5d607666239b34,
                         0xeddb5f48304d14b3,
@@ -2009,7 +2060,8 @@ pub mod g2 {
                         0xb271f52f12ead742,
                         0x244e6c2015c83348,
                         0x19e2deae6eb9b441
-                    ])).unwrap(),
+                    ]))
+                    .unwrap(),
                 },
                 infinity: false,
             }
@@ -2018,7 +2070,8 @@ pub mod g2 {
 
     #[test]
     fn g2_curve_tests() {
-        ::tests::curve::curve_tests::<G2>();
+        use group::tests::curve_tests;
+        curve_tests::<G2>();
     }
 }
 

pairing/src/bls12_381/fq12.rs

@@ -1,8 +1,8 @@
 use super::fq::FROBENIUS_COEFF_FQ12_C1;
 use super::fq2::Fq2;
 use super::fq6::Fq6;
-use rand::{Rand, Rng};
+use ff::Field;
-use Field;
+use rand_core::RngCore;
 
 /// An element of Fq12, represented by c0 + c1 * w.
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
@@ -17,15 +17,6 @@ impl ::std::fmt::Display for Fq12 {
     }
 }
 
-impl Rand for Fq12 {
-    fn rand<R: Rng>(rng: &mut R) -> Self {
-        Fq12 {
-            c0: rng.gen(),
-            c1: rng.gen(),
-        }
-    }
-}
-
 impl Fq12 {
     pub fn conjugate(&mut self) {
         self.c1.negate();
@@ -49,6 +40,13 @@ impl Fq12 {
 }
 
 impl Field for Fq12 {
+    fn random<R: RngCore>(rng: &mut R) -> Self {
+        Fq12 {
+            c0: Fq6::random(rng),
+            c1: Fq6::random(rng),
+        }
+    }
+
     fn zero() -> Self {
         Fq12 {
             c0: Fq6::zero(),
@@ -149,24 +147,29 @@ impl Field for Fq12 {
 }
 
 #[cfg(test)]
-use rand::{SeedableRng, XorShiftRng};
+use rand_core::SeedableRng;
+#[cfg(test)]
+use rand_xorshift::XorShiftRng;
 
 #[test]
 fn test_fq12_mul_by_014() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let c0 = Fq2::rand(&mut rng);
+        let c0 = Fq2::random(&mut rng);
-        let c1 = Fq2::rand(&mut rng);
+        let c1 = Fq2::random(&mut rng);
-        let c5 = Fq2::rand(&mut rng);
+        let c5 = Fq2::random(&mut rng);
-        let mut a = Fq12::rand(&mut rng);
+        let mut a = Fq12::random(&mut rng);
         let mut b = a;
 
         a.mul_by_014(&c0, &c1, &c5);
         b.mul_assign(&Fq12 {
             c0: Fq6 {
-                c0: c0,
+                c0,
-                c1: c1,
+                c1,
                 c2: Fq2::zero(),
             },
             c1: Fq6 {
@@ -182,7 +185,7 @@ fn test_fq12_mul_by_014() {
 
 #[test]
 fn fq12_field_tests() {
-    use PrimeField;
+    use ff::PrimeField;
 
     ::tests::field::random_field_tests::<Fq12>();
     ::tests::field::random_frobenius_tests::<Fq12, _>(super::fq::Fq::char(), 13);

pairing/src/bls12_381/fq2.rs

@@ -1,6 +1,6 @@
-use super::fq::{FROBENIUS_COEFF_FQ2_C1, Fq, NEGATIVE_ONE};
+use super::fq::{Fq, FROBENIUS_COEFF_FQ2_C1, NEGATIVE_ONE};
-use rand::{Rand, Rng};
+use ff::{Field, SqrtField};
-use {Field, SqrtField};
+use rand_core::RngCore;
 
 use std::cmp::Ordering;
 
@@ -56,16 +56,14 @@ impl Fq2 {
     }
 }
 
-impl Rand for Fq2 {
+impl Field for Fq2 {
-    fn rand<R: Rng>(rng: &mut R) -> Self {
+    fn random<R: RngCore>(rng: &mut R) -> Self {
         Fq2 {
-            c0: rng.gen(),
+            c0: Fq::random(rng),
-            c1: rng.gen(),
+            c1: Fq::random(rng),
         }
     }
-}
 
-impl Field for Fq2 {
     fn zero() -> Self {
         Fq2 {
             c0: Fq::zero(),
@@ -160,7 +158,7 @@ impl Field for Fq2 {
 }
 
 impl SqrtField for Fq2 {
-    fn legendre(&self) -> ::LegendreSymbol {
+    fn legendre(&self) -> ::ff::LegendreSymbol {
         self.norm().legendre()
     }
 
@@ -266,13 +264,14 @@ fn test_fq2_basics() {
     assert!(!Fq2 {
         c0: Fq::zero(),
         c1: Fq::one(),
-    }.is_zero());
+    }
+    .is_zero());
 }
 
 #[test]
 fn test_fq2_squaring() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     let mut a = Fq2 {
         c0: Fq::one(),
@@ -309,7 +308,8 @@ fn test_fq2_squaring() {
             0xf7f295a94e58ae7c,
             0x41b76dcc1c3fbe5e,
             0x7080c5fa1d8e042,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x38f473b3c870a4ab,
             0x6ad3291177c8c7e5,
@@ -317,7 +317,8 @@ fn test_fq2_squaring() {
             0xbfb99020604137a0,
             0xfc58a7b7be815407,
             0x10d1615e75250a21,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     };
     a.square();
     assert_eq!(
@@ -330,7 +331,8 @@ fn test_fq2_squaring() {
                 0xcb674157618da176,
                 0x4cf17b5893c3d327,
                 0x7eac81369c43361
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0xc1579cf58e980cf8,
                 0xa23eb7e12dd54d98,
@@ -338,7 +340,8 @@ fn test_fq2_squaring() {
                 0x38d0d7275a9689e1,
                 0x739c983042779a65,
                 0x1542a61c8a8db994
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
@@ -346,7 +349,7 @@ fn test_fq2_squaring() {
 #[test]
 fn test_fq2_mul() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     let mut a = Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -356,7 +359,8 @@ fn test_fq2_mul() {
             0x9ee53e7e84d7532e,
             0x1c202d8ed97afb45,
             0x51d3f9253e2516f,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0xa7348a8b511aedcf,
             0x143c215d8176b319,
@@ -364,7 +368,8 @@ fn test_fq2_mul() {
             0x9533e4a9a5158be,
             0x7a5e1ecb676d65f9,
             0x180c3ee46656b008,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     };
     a.mul_assign(&Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -374,7 +379,8 @@ fn test_fq2_mul() {
             0xcd460f9f0c23e430,
             0x6c9110292bfa409,
             0x2c93a72eb8af83e,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x4b1c3f936d8992d4,
             0x1d2a72916dba4c8a,
@@ -382,7 +388,8 @@ fn test_fq2_mul() {
             0x57a06d3135a752ae,
             0x634cd3c6c565096d,
             0x19e17334d4e93558,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     });
     assert_eq!(
         a,
@@ -394,7 +401,8 @@ fn test_fq2_mul() {
                 0x5511fe4d84ee5f78,
                 0x5310a202d92f9963,
                 0x1751afbe166e5399
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0x84af0e1bd630117a,
                 0x6c63cd4da2c2aa7,
@@ -402,7 +410,8 @@ fn test_fq2_mul() {
                 0xc975106579c275ee,
                 0x33a9ac82ce4c5083,
                 0x1ef1a36c201589d
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
@@ -410,7 +419,7 @@ fn test_fq2_mul() {
 #[test]
 fn test_fq2_inverse() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     assert!(Fq2::zero().inverse().is_none());
 
@@ -422,7 +431,8 @@ fn test_fq2_inverse() {
             0x9ee53e7e84d7532e,
             0x1c202d8ed97afb45,
             0x51d3f9253e2516f,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0xa7348a8b511aedcf,
             0x143c215d8176b319,
@@ -430,7 +440,8 @@ fn test_fq2_inverse() {
             0x9533e4a9a5158be,
             0x7a5e1ecb676d65f9,
             0x180c3ee46656b008,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     };
     let a = a.inverse().unwrap();
     assert_eq!(
@@ -443,7 +454,8 @@ fn test_fq2_inverse() {
                 0xdfba703293941c30,
                 0xa6c3d8f9586f2636,
                 0x1351ef01941b70c4
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0x8c39fd76a8312cb4,
                 0x15d7b6b95defbff0,
@@ -451,7 +463,8 @@ fn test_fq2_inverse() {
                 0xcbf651a0f367afb2,
                 0xdf4e54f0d3ef15a6,
                 0x103bdf241afb0019
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
@@ -459,7 +472,7 @@ fn test_fq2_inverse() {
 #[test]
 fn test_fq2_addition() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     let mut a = Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -469,7 +482,8 @@ fn test_fq2_addition() {
             0xb966ce3bc2108b13,
             0xccc649c4b9532bf3,
             0xf8d295b2ded9dc,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x977df6efcdaee0db,
             0x946ae52d684fa7ed,
@@ -477,7 +491,8 @@ fn test_fq2_addition() {
             0xb3f8afc0ee248cad,
             0x4e464dea5bcfd41e,
             0x12d1137b8a6a837,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     };
     a.add_assign(&Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -487,7 +502,8 @@ fn test_fq2_addition() {
             0x3b88899a42a6318f,
             0x986a4a62fa82a49d,
             0x13ce433fa26027f5,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x66323bf80b58b9b9,
             0xa1379b6facf6e596,
@@ -495,7 +511,8 @@ fn test_fq2_addition() {
             0x2236f55246d0d44d,
             0x4c8c1800eb104566,
             0x11d6e20e986c2085,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     });
     assert_eq!(
         a,
@@ -507,7 +524,8 @@ fn test_fq2_addition() {
                 0xf4ef57d604b6bca2,
                 0x65309427b3d5d090,
                 0x14c715d5553f01d2
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0xfdb032e7d9079a94,
                 0x35a2809d15468d83,
@@ -515,7 +533,8 @@ fn test_fq2_addition() {
                 0xd62fa51334f560fa,
                 0x9ad265eb46e01984,
                 0x1303f3465112c8bc
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
@@ -523,7 +542,7 @@ fn test_fq2_addition() {
 #[test]
 fn test_fq2_subtraction() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     let mut a = Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -533,7 +552,8 @@ fn test_fq2_subtraction() {
             0xb966ce3bc2108b13,
             0xccc649c4b9532bf3,
             0xf8d295b2ded9dc,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x977df6efcdaee0db,
             0x946ae52d684fa7ed,
@@ -541,7 +561,8 @@ fn test_fq2_subtraction() {
             0xb3f8afc0ee248cad,
             0x4e464dea5bcfd41e,
             0x12d1137b8a6a837,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     };
     a.sub_assign(&Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -551,7 +572,8 @@ fn test_fq2_subtraction() {
             0x3b88899a42a6318f,
             0x986a4a62fa82a49d,
             0x13ce433fa26027f5,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x66323bf80b58b9b9,
             0xa1379b6facf6e596,
@@ -559,7 +581,8 @@ fn test_fq2_subtraction() {
             0x2236f55246d0d44d,
             0x4c8c1800eb104566,
             0x11d6e20e986c2085,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     });
     assert_eq!(
         a,
@@ -571,7 +594,8 @@ fn test_fq2_subtraction() {
                 0xe255902672ef6c43,
                 0x7f77a718021c342d,
                 0x72ba14049fe9881
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0xeb4abaf7c255d1cd,
                 0x11df49bc6cacc256,
@@ -579,7 +603,8 @@ fn test_fq2_subtraction() {
                 0xf63905f39ad8cb1f,
                 0x4cd5dd9fb40b3b8f,
                 0x957411359ba6e4c
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
@@ -587,7 +612,7 @@ fn test_fq2_subtraction() {
 #[test]
 fn test_fq2_negation() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     let mut a = Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -597,7 +622,8 @@ fn test_fq2_negation() {
             0xb966ce3bc2108b13,
             0xccc649c4b9532bf3,
             0xf8d295b2ded9dc,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x977df6efcdaee0db,
             0x946ae52d684fa7ed,
@@ -605,7 +631,8 @@ fn test_fq2_negation() {
             0xb3f8afc0ee248cad,
             0x4e464dea5bcfd41e,
             0x12d1137b8a6a837,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     };
     a.negate();
     assert_eq!(
@@ -618,7 +645,8 @@ fn test_fq2_negation() {
                 0xab107d49317487ab,
                 0x7e555df189f880e3,
                 0x19083f5486a10cbd
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0x228109103250c9d0,
                 0x8a411ad149045812,
@@ -626,7 +654,8 @@ fn test_fq2_negation() {
                 0xb07e9bc405608611,
                 0xfcd559cbe77bd8b8,
                 0x18d400b280d93e62
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
@@ -634,7 +663,7 @@ fn test_fq2_negation() {
 #[test]
 fn test_fq2_doubling() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     let mut a = Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -644,7 +673,8 @@ fn test_fq2_doubling() {
             0xb966ce3bc2108b13,
             0xccc649c4b9532bf3,
             0xf8d295b2ded9dc,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x977df6efcdaee0db,
             0x946ae52d684fa7ed,
@@ -652,7 +682,8 @@ fn test_fq2_doubling() {
             0xb3f8afc0ee248cad,
             0x4e464dea5bcfd41e,
             0x12d1137b8a6a837,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     };
     a.double();
     assert_eq!(
@@ -665,7 +696,8 @@ fn test_fq2_doubling() {
                 0x72cd9c7784211627,
                 0x998c938972a657e7,
                 0x1f1a52b65bdb3b9
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0x2efbeddf9b5dc1b6,
                 0x28d5ca5ad09f4fdb,
@@ -673,7 +705,8 @@ fn test_fq2_doubling() {
                 0x67f15f81dc49195b,
                 0x9c8c9bd4b79fa83d,
                 0x25a226f714d506e
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
@@ -681,7 +714,7 @@ fn test_fq2_doubling() {
 #[test]
 fn test_fq2_frobenius_map() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     let mut a = Fq2 {
         c0: Fq::from_repr(FqRepr([
@@ -691,7 +724,8 @@ fn test_fq2_frobenius_map() {
             0xb966ce3bc2108b13,
             0xccc649c4b9532bf3,
             0xf8d295b2ded9dc,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
         c1: Fq::from_repr(FqRepr([
             0x977df6efcdaee0db,
             0x946ae52d684fa7ed,
@@ -699,7 +733,8 @@ fn test_fq2_frobenius_map() {
             0xb3f8afc0ee248cad,
             0x4e464dea5bcfd41e,
             0x12d1137b8a6a837,
-        ])).unwrap(),
+        ]))
+        .unwrap(),
     };
     a.frobenius_map(0);
     assert_eq!(
@@ -712,7 +747,8 @@ fn test_fq2_frobenius_map() {
                 0xb966ce3bc2108b13,
                 0xccc649c4b9532bf3,
                 0xf8d295b2ded9dc
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0x977df6efcdaee0db,
                 0x946ae52d684fa7ed,
@@ -720,7 +756,8 @@ fn test_fq2_frobenius_map() {
                 0xb3f8afc0ee248cad,
                 0x4e464dea5bcfd41e,
                 0x12d1137b8a6a837
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
     a.frobenius_map(1);
@@ -734,7 +771,8 @@ fn test_fq2_frobenius_map() {
                 0xb966ce3bc2108b13,
                 0xccc649c4b9532bf3,
                 0xf8d295b2ded9dc
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0x228109103250c9d0,
                 0x8a411ad149045812,
@@ -742,7 +780,8 @@ fn test_fq2_frobenius_map() {
                 0xb07e9bc405608611,
                 0xfcd559cbe77bd8b8,
                 0x18d400b280d93e62
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
     a.frobenius_map(1);
@@ -756,7 +795,8 @@ fn test_fq2_frobenius_map() {
                 0xb966ce3bc2108b13,
                 0xccc649c4b9532bf3,
                 0xf8d295b2ded9dc
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0x977df6efcdaee0db,
                 0x946ae52d684fa7ed,
@@ -764,7 +804,8 @@ fn test_fq2_frobenius_map() {
                 0xb3f8afc0ee248cad,
                 0x4e464dea5bcfd41e,
                 0x12d1137b8a6a837
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
     a.frobenius_map(2);
@@ -778,7 +819,8 @@ fn test_fq2_frobenius_map() {
                 0xb966ce3bc2108b13,
                 0xccc649c4b9532bf3,
                 0xf8d295b2ded9dc
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0x977df6efcdaee0db,
                 0x946ae52d684fa7ed,
@@ -786,7 +828,8 @@ fn test_fq2_frobenius_map() {
                 0xb3f8afc0ee248cad,
                 0x4e464dea5bcfd41e,
                 0x12d1137b8a6a837
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
@@ -794,7 +837,7 @@ fn test_fq2_frobenius_map() {
 #[test]
 fn test_fq2_sqrt() {
     use super::fq::FqRepr;
-    use PrimeField;
+    use ff::PrimeField;
 
     assert_eq!(
         Fq2 {
@@ -805,7 +848,8 @@ fn test_fq2_sqrt() {
                 0xdb4a116b5bf74aa1,
                 0x1e58b2159dfe10e2,
                 0x7ca7da1f13606ac
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0xfa8de88b7516d2c3,
                 0x371a75ed14f41629,
@@ -813,9 +857,11 @@ fn test_fq2_sqrt() {
                 0x212611bca4e99121,
                 0x8ee5394d77afb3d,
                 0xec92336650e49d5
-            ])).unwrap(),
+            ]))
-        }.sqrt()
             .unwrap(),
+        }
+        .sqrt()
+        .unwrap(),
         Fq2 {
             c0: Fq::from_repr(FqRepr([
                 0x40b299b2704258c5,
@@ -824,7 +870,8 @@ fn test_fq2_sqrt() {
                 0x8d7f1f723d02c1d3,
                 0x881b3e01b611c070,
                 0x10f6963bbad2ebc5
-            ])).unwrap(),
+            ]))
+            .unwrap(),
             c1: Fq::from_repr(FqRepr([
                 0xc099534fc209e752,
                 0x7670594665676447,
@@ -832,7 +879,8 @@ fn test_fq2_sqrt() {
                 0x6b852aeaf2afcb1b,
                 0xa4c93b08105d71a9,
                 0x8d7cfff94216330
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 
@@ -845,10 +893,12 @@ fn test_fq2_sqrt() {
                 0x64774b84f38512bf,
                 0x4b1ba7b6434bacd7,
                 0x1a0111ea397fe69a
-            ])).unwrap(),
+            ]))
-            c1: Fq::zero(),
-        }.sqrt()
             .unwrap(),
+            c1: Fq::zero(),
+        }
+        .sqrt()
+        .unwrap(),
         Fq2 {
             c0: Fq::zero(),
             c1: Fq::from_repr(FqRepr([
@@ -858,14 +908,15 @@ fn test_fq2_sqrt() {
                 0x64774b84f38512bf,
                 0x4b1ba7b6434bacd7,
                 0x1a0111ea397fe69a
-            ])).unwrap(),
+            ]))
+            .unwrap(),
         }
     );
 }
 
 #[test]
 fn test_fq2_legendre() {
-    use LegendreSymbol::*;
+    use ff::LegendreSymbol::*;
 
     assert_eq!(Zero, Fq2::zero().legendre());
     // i^2 = -1
@@ -877,11 +928,16 @@ fn test_fq2_legendre() {
 }
 
 #[cfg(test)]
-use rand::{SeedableRng, XorShiftRng};
+use rand_core::SeedableRng;
+#[cfg(test)]
+use rand_xorshift::XorShiftRng;
 
 #[test]
 fn test_fq2_mul_nonresidue() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     let nqr = Fq2 {
         c0: Fq::one(),
@@ -889,7 +945,7 @@ fn test_fq2_mul_nonresidue() {
     };
 
     for _ in 0..1000 {
-        let mut a = Fq2::rand(&mut rng);
+        let mut a = Fq2::random(&mut rng);
         let mut b = a;
         a.mul_by_nonresidue();
         b.mul_assign(&nqr);
@@ -900,7 +956,7 @@ fn test_fq2_mul_nonresidue() {
 
 #[test]
 fn fq2_field_tests() {
-    use PrimeField;
+    use ff::PrimeField;
 
     ::tests::field::random_field_tests::<Fq2>();
     ::tests::field::random_sqrt_tests::<Fq2>();

pairing/src/bls12_381/fq6.rs

@@ -1,7 +1,7 @@
 use super::fq::{FROBENIUS_COEFF_FQ6_C1, FROBENIUS_COEFF_FQ6_C2};
 use super::fq2::Fq2;
-use rand::{Rand, Rng};
+use ff::Field;
-use Field;
+use rand_core::RngCore;
 
 /// An element of Fq6, represented by c0 + c1 * v + c2 * v^(2).
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
@@ -17,16 +17,6 @@ impl ::std::fmt::Display for Fq6 {
     }
 }
 
-impl Rand for Fq6 {
-    fn rand<R: Rng>(rng: &mut R) -> Self {
-        Fq6 {
-            c0: rng.gen(),
-            c1: rng.gen(),
-            c2: rng.gen(),
-        }
-    }
-}
-
 impl Fq6 {
     /// Multiply by quadratic nonresidue v.
     pub fn mul_by_nonresidue(&mut self) {
@@ -110,6 +100,14 @@ impl Fq6 {
 }
 
 impl Field for Fq6 {
+    fn random<R: RngCore>(rng: &mut R) -> Self {
+        Fq6 {
+            c0: Fq2::random(rng),
+            c1: Fq2::random(rng),
+            c2: Fq2::random(rng),
+        }
+    }
+
     fn zero() -> Self {
         Fq6 {
             c0: Fq2::zero(),
@@ -302,11 +300,16 @@ impl Field for Fq6 {
 }
 
 #[cfg(test)]
-use rand::{SeedableRng, XorShiftRng};
+use rand_core::SeedableRng;
+#[cfg(test)]
+use rand_xorshift::XorShiftRng;
 
 #[test]
 fn test_fq6_mul_nonresidue() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     let nqr = Fq6 {
         c0: Fq2::zero(),
@@ -315,7 +318,7 @@ fn test_fq6_mul_nonresidue() {
     };
 
     for _ in 0..1000 {
-        let mut a = Fq6::rand(&mut rng);
+        let mut a = Fq6::random(&mut rng);
         let mut b = a;
         a.mul_by_nonresidue();
         b.mul_assign(&nqr);
@@ -326,17 +329,20 @@ fn test_fq6_mul_nonresidue() {
 
 #[test]
 fn test_fq6_mul_by_1() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let c1 = Fq2::rand(&mut rng);
+        let c1 = Fq2::random(&mut rng);
-        let mut a = Fq6::rand(&mut rng);
+        let mut a = Fq6::random(&mut rng);
         let mut b = a;
 
         a.mul_by_1(&c1);
         b.mul_assign(&Fq6 {
             c0: Fq2::zero(),
-            c1: c1,
+            c1,
             c2: Fq2::zero(),
         });
 
@@ -346,18 +352,21 @@ fn test_fq6_mul_by_1() {
 
 #[test]
 fn test_fq6_mul_by_01() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let c0 = Fq2::rand(&mut rng);
+        let c0 = Fq2::random(&mut rng);
-        let c1 = Fq2::rand(&mut rng);
+        let c1 = Fq2::random(&mut rng);
-        let mut a = Fq6::rand(&mut rng);
+        let mut a = Fq6::random(&mut rng);
         let mut b = a;
 
         a.mul_by_01(&c0, &c1);
         b.mul_assign(&Fq6 {
-            c0: c0,
+            c0,
-            c1: c1,
+            c1,
             c2: Fq2::zero(),
         });
 
@@ -367,7 +376,7 @@ fn test_fq6_mul_by_01() {
 
 #[test]
 fn fq6_field_tests() {
-    use PrimeField;
+    use ff::PrimeField;
 
     ::tests::field::random_field_tests::<Fq6>();
     ::tests::field::random_frobenius_tests::<Fq6, _>(super::fq::Fq::char(), 13);

pairing/src/bls12_381/mod.rs

@@ -9,8 +9,8 @@ mod fr;
 mod tests;
 
 pub use self::ec::{
-    G1, G1Affine, G1Compressed, G1Prepared, G1Uncompressed, G2, G2Affine, G2Compressed, G2Prepared,
+    G1Affine, G1Compressed, G1Prepared, G1Uncompressed, G2Affine, G2Compressed, G2Prepared,
-    G2Uncompressed,
+    G2Uncompressed, G1, G2,
 };
 pub use self::fq::{Fq, FqRepr};
 pub use self::fq12::Fq12;
@@ -18,7 +18,10 @@ pub use self::fq2::Fq2;
 pub use self::fq6::Fq6;
 pub use self::fr::{Fr, FrRepr};
 
-use super::{BitIterator, CurveAffine, Engine, Field};
+use super::{Engine, PairingCurveAffine};
+
+use ff::{BitIterator, Field, ScalarEngine};
+use group::CurveAffine;
 
 // The BLS parameter x for BLS12-381 is -0xd201000000010000
 const BLS_X: u64 = 0xd201000000010000;
@@ -27,8 +30,11 @@ const BLS_X_IS_NEGATIVE: bool = true;
 #[derive(Clone, Debug)]
 pub struct Bls12;
 
-impl Engine for Bls12 {
+impl ScalarEngine for Bls12 {
     type Fr = Fr;
+}
+
+impl Engine for Bls12 {
     type G1 = G1;
     type G1Affine = G1Affine;
     type G2 = G2;
@@ -41,8 +47,8 @@ impl Engine for Bls12 {
     where
         I: IntoIterator<
             Item = &'a (
-                &'a <Self::G1Affine as CurveAffine>::Prepared,
+                &'a <Self::G1Affine as PairingCurveAffine>::Prepared,
-                &'a <Self::G2Affine as CurveAffine>::Prepared,
+                &'a <Self::G2Affine as PairingCurveAffine>::Prepared,
             ),
         >,
     {

pairing/src/bls12_381/tests/mod.rs

@@ -1,3 +1,6 @@
+use ff::PrimeFieldRepr;
+use group::{CurveAffine, CurveProjective, EncodedPoint, GroupDecodingError};
+
 use super::*;
 use *;
 

pairing/src/lib.rs

@@ -1,59 +1,53 @@
 // `clippy` is a code linting tool for improving code quality by catching
-// common mistakes or strange code patterns. If the `clippy` feature is
+// common mistakes or strange code patterns. If the `cargo-clippy` feature
-// provided, it is enabled and all compiler warnings are prohibited.
+// is provided, all compiler warnings are prohibited.
-#![cfg_attr(feature = "clippy", deny(warnings))]
+#![cfg_attr(feature = "cargo-clippy", deny(warnings))]
-#![cfg_attr(feature = "clippy", feature(plugin))]
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::inline_always))]
-#![cfg_attr(feature = "clippy", plugin(clippy))]
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::too_many_arguments))]
-#![cfg_attr(feature = "clippy", allow(inline_always))]
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::unreadable_literal))]
-#![cfg_attr(feature = "clippy", allow(too_many_arguments))]
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::many_single_char_names))]
-#![cfg_attr(feature = "clippy", allow(unreadable_literal))]
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::new_without_default))]
-#![cfg_attr(feature = "clippy", allow(many_single_char_names))]
+#![cfg_attr(feature = "cargo-clippy", allow(clippy::write_literal))]
-#![cfg_attr(feature = "clippy", allow(new_without_default_derive))]
-#![cfg_attr(feature = "clippy", allow(write_literal))]
 // Force public structures to implement Debug
 #![deny(missing_debug_implementations)]
 
 extern crate byteorder;
-extern crate rand;
+extern crate ff;
+extern crate group;
+extern crate rand_core;
+
+#[cfg(test)]
+extern crate rand_xorshift;
 
 #[cfg(test)]
 pub mod tests;
 
 pub mod bls12_381;
 
-mod wnaf;
+use ff::{Field, PrimeField, ScalarEngine, SqrtField};
-pub use self::wnaf::Wnaf;
+use group::{CurveAffine, CurveProjective};
-
-use std::error::Error;
-use std::fmt;
-use std::io::{self, Read, Write};
 
 /// An "engine" is a collection of types (fields, elliptic curve groups, etc.)
 /// with well-defined relationships. In particular, the G1/G2 curve groups are
 /// of prime order `r`, and are equipped with a bilinear pairing function.
-pub trait Engine: Sized + 'static + Clone {
+pub trait Engine: ScalarEngine {
-    /// This is the scalar field of the G1/G2 groups.
-    type Fr: PrimeField + SqrtField;
-
     /// The projective representation of an element in G1.
     type G1: CurveProjective<
             Engine = Self,
             Base = Self::Fq,
             Scalar = Self::Fr,
             Affine = Self::G1Affine,
-        >
+        > + From<Self::G1Affine>;
-        + From<Self::G1Affine>;
 
     /// The affine representation of an element in G1.
-    type G1Affine: CurveAffine<
+    type G1Affine: PairingCurveAffine<
             Engine = Self,
             Base = Self::Fq,
             Scalar = Self::Fr,
             Projective = Self::G1,
             Pair = Self::G2Affine,
             PairingResult = Self::Fqk,
-        >
+        > + From<Self::G1>;
-        + From<Self::G1>;
 
     /// The projective representation of an element in G2.
     type G2: CurveProjective<
@@ -61,19 +55,17 @@ pub trait Engine: Sized + 'static + Clone {
             Base = Self::Fqe,
             Scalar = Self::Fr,
             Affine = Self::G2Affine,
-        >
+        > + From<Self::G2Affine>;
-        + From<Self::G2Affine>;
 
     /// The affine representation of an element in G2.
-    type G2Affine: CurveAffine<
+    type G2Affine: PairingCurveAffine<
             Engine = Self,
             Base = Self::Fqe,
             Scalar = Self::Fr,
             Projective = Self::G2,
             Pair = Self::G1Affine,
             PairingResult = Self::Fqk,
-        >
+        > + From<Self::G2>;
-        + From<Self::G2>;
 
     /// The base field that hosts G1.
     type Fq: PrimeField + SqrtField;
@@ -89,8 +81,8 @@ pub trait Engine: Sized + 'static + Clone {
     where
         I: IntoIterator<
             Item = &'a (
-                &'a <Self::G1Affine as CurveAffine>::Prepared,
+                &'a <Self::G1Affine as PairingCurveAffine>::Prepared,
-                &'a <Self::G2Affine as CurveAffine>::Prepared,
+                &'a <Self::G2Affine as PairingCurveAffine>::Prepared,
             ),
         >;
 
@@ -104,655 +96,22 @@ pub trait Engine: Sized + 'static + Clone {
         G2: Into<Self::G2Affine>,
     {
         Self::final_exponentiation(&Self::miller_loop(
-            [(&(p.into().prepare()), &(q.into().prepare()))].into_iter(),
+            [(&(p.into().prepare()), &(q.into().prepare()))].iter(),
-        )).unwrap()
+        ))
+        .unwrap()
     }
 }
 
-/// Projective representation of an elliptic curve point guaranteed to be
+/// Affine representation of an elliptic curve point that can be used
-/// in the correct prime order subgroup.
+/// to perform pairings.
-pub trait CurveProjective:
+pub trait PairingCurveAffine: CurveAffine {
-    PartialEq
-    + Eq
-    + Sized
-    + Copy
-    + Clone
-    + Send
-    + Sync
-    + fmt::Debug
-    + fmt::Display
-    + rand::Rand
-    + 'static
-{
-    type Engine: Engine<Fr = Self::Scalar>;
-    type Scalar: PrimeField + SqrtField;
-    type Base: SqrtField;
-    type Affine: CurveAffine<Projective = Self, Scalar = Self::Scalar>;
-
-    /// Returns the additive identity.
-    fn zero() -> Self;
-
-    /// Returns a fixed generator of unknown exponent.
-    fn one() -> Self;
-
-    /// Determines if this point is the point at infinity.
-    fn is_zero(&self) -> bool;
-
-    /// Normalizes a slice of projective elements so that
-    /// conversion to affine is cheap.
-    fn batch_normalization(v: &mut [Self]);
-
-    /// Checks if the point is already "normalized" so that
-    /// cheap affine conversion is possible.
-    fn is_normalized(&self) -> bool;
-
-    /// Doubles this element.
-    fn double(&mut self);
-
-    /// Adds another element to this element.
-    fn add_assign(&mut self, other: &Self);
-
-    /// Subtracts another element from this element.
-    fn sub_assign(&mut self, other: &Self) {
-        let mut tmp = *other;
-        tmp.negate();
-        self.add_assign(&tmp);
-    }
-
-    /// Adds an affine element to this element.
-    fn add_assign_mixed(&mut self, other: &Self::Affine);
-
-    /// Negates this element.
-    fn negate(&mut self);
-
-    /// Performs scalar multiplication of this element.
-    fn mul_assign<S: Into<<Self::Scalar as PrimeField>::Repr>>(&mut self, other: S);
-
-    /// Converts this element into its affine representation.
-    fn into_affine(&self) -> Self::Affine;
-
-    /// Recommends a wNAF window table size given a scalar. Always returns a number
-    /// between 2 and 22, inclusive.
-    fn recommended_wnaf_for_scalar(scalar: <Self::Scalar as PrimeField>::Repr) -> usize;
-
-    /// Recommends a wNAF window size given the number of scalars you intend to multiply
-    /// a base by. Always returns a number between 2 and 22, inclusive.
-    fn recommended_wnaf_for_num_scalars(num_scalars: usize) -> usize;
-}
-
-/// Affine representation of an elliptic curve point guaranteed to be
-/// in the correct prime order subgroup.
-pub trait CurveAffine:
-    Copy + Clone + Sized + Send + Sync + fmt::Debug + fmt::Display + PartialEq + Eq + 'static
-{
-    type Engine: Engine<Fr = Self::Scalar>;
-    type Scalar: PrimeField + SqrtField;
-    type Base: SqrtField;
-    type Projective: CurveProjective<Affine = Self, Scalar = Self::Scalar>;
     type Prepared: Clone + Send + Sync + 'static;
-    type Uncompressed: EncodedPoint<Affine = Self>;
+    type Pair: PairingCurveAffine<Pair = Self>;
-    type Compressed: EncodedPoint<Affine = Self>;
-    type Pair: CurveAffine<Pair = Self>;
     type PairingResult: Field;
 
-    /// Returns the additive identity.
-    fn zero() -> Self;
-
-    /// Returns a fixed generator of unknown exponent.
-    fn one() -> Self;
-
-    /// Determines if this point represents the point at infinity; the
-    /// additive identity.
-    fn is_zero(&self) -> bool;
-
-    /// Negates this element.
-    fn negate(&mut self);
-
-    /// Performs scalar multiplication of this element with mixed addition.
-    fn mul<S: Into<<Self::Scalar as PrimeField>::Repr>>(&self, other: S) -> Self::Projective;
-
     /// Prepares this element for pairing purposes.
     fn prepare(&self) -> Self::Prepared;
 
     /// Perform a pairing
     fn pairing_with(&self, other: &Self::Pair) -> Self::PairingResult;
-
-    /// Converts this element into its affine representation.
-    fn into_projective(&self) -> Self::Projective;
-
-    /// Converts this element into its compressed encoding, so long as it's not
-    /// the point at infinity.
-    fn into_compressed(&self) -> Self::Compressed {
-        <Self::Compressed as EncodedPoint>::from_affine(*self)
-    }
-
-    /// Converts this element into its uncompressed encoding, so long as it's not
-    /// the point at infinity.
-    fn into_uncompressed(&self) -> Self::Uncompressed {
-        <Self::Uncompressed as EncodedPoint>::from_affine(*self)
-    }
-}
-
-/// An encoded elliptic curve point, which should essentially wrap a `[u8; N]`.
-pub trait EncodedPoint:
-    Sized + Send + Sync + AsRef<[u8]> + AsMut<[u8]> + Clone + Copy + 'static
-{
-    type Affine: CurveAffine;
-
-    /// Creates an empty representation.
-    fn empty() -> Self;
-
-    /// Returns the number of bytes consumed by this representation.
-    fn size() -> usize;
-
-    /// Converts an `EncodedPoint` into a `CurveAffine` element,
-    /// if the encoding represents a valid element.
-    fn into_affine(&self) -> Result<Self::Affine, GroupDecodingError>;
-
-    /// Converts an `EncodedPoint` into a `CurveAffine` element,
-    /// without guaranteeing that the encoding represents a valid
-    /// element. This is useful when the caller knows the encoding is
-    /// valid already.
-    ///
-    /// If the encoding is invalid, this can break API invariants,
-    /// so caution is strongly encouraged.
-    fn into_affine_unchecked(&self) -> Result<Self::Affine, GroupDecodingError>;
-
-    /// Creates an `EncodedPoint` from an affine point, as long as the
-    /// point is not the point at infinity.
-    fn from_affine(affine: Self::Affine) -> Self;
-}
-
-/// This trait represents an element of a field.
-pub trait Field:
-    Sized + Eq + Copy + Clone + Send + Sync + fmt::Debug + fmt::Display + 'static + rand::Rand
-{
-    /// Returns the zero element of the field, the additive identity.
-    fn zero() -> Self;
-
-    /// Returns the one element of the field, the multiplicative identity.
-    fn one() -> Self;
-
-    /// Returns true iff this element is zero.
-    fn is_zero(&self) -> bool;
-
-    /// Squares this element.
-    fn square(&mut self);
-
-    /// Doubles this element.
-    fn double(&mut self);
-
-    /// Negates this element.
-    fn negate(&mut self);
-
-    /// Adds another element to this element.
-    fn add_assign(&mut self, other: &Self);
-
-    /// Subtracts another element from this element.
-    fn sub_assign(&mut self, other: &Self);
-
-    /// Multiplies another element by this element.
-    fn mul_assign(&mut self, other: &Self);
-
-    /// Computes the multiplicative inverse of this element, if nonzero.
-    fn inverse(&self) -> Option<Self>;
-
-    /// Exponentiates this element by a power of the base prime modulus via
-    /// the Frobenius automorphism.
-    fn frobenius_map(&mut self, power: usize);
-
-    /// Exponentiates this element by a number represented with `u64` limbs,
-    /// least significant digit first.
-    fn pow<S: AsRef<[u64]>>(&self, exp: S) -> Self {
-        let mut res = Self::one();
-
-        let mut found_one = false;
-
-        for i in BitIterator::new(exp) {
-            if found_one {
-                res.square();
-            } else {
-                found_one = i;
-            }
-
-            if i {
-                res.mul_assign(self);
-            }
-        }
-
-        res
-    }
-}
-
-/// This trait represents an element of a field that has a square root operation described for it.
-pub trait SqrtField: Field {
-    /// Returns the Legendre symbol of the field element.
-    fn legendre(&self) -> LegendreSymbol;
-
-    /// Returns the square root of the field element, if it is
-    /// quadratic residue.
-    fn sqrt(&self) -> Option<Self>;
-}
-
-/// This trait represents a wrapper around a biginteger which can encode any element of a particular
-/// prime field. It is a smart wrapper around a sequence of `u64` limbs, least-significant digit
-/// first.
-pub trait PrimeFieldRepr:
-    Sized
-    + Copy
-    + Clone
-    + Eq
-    + Ord
-    + Send
-    + Sync
-    + Default
-    + fmt::Debug
-    + fmt::Display
-    + 'static
-    + rand::Rand
-    + AsRef<[u64]>
-    + AsMut<[u64]>
-    + From<u64>
-{
-    /// Subtract another represetation from this one.
-    fn sub_noborrow(&mut self, other: &Self);
-
-    /// Add another representation to this one.
-    fn add_nocarry(&mut self, other: &Self);
-
-    /// Compute the number of bits needed to encode this number. Always a
-    /// multiple of 64.
-    fn num_bits(&self) -> u32;
-
-    /// Returns true iff this number is zero.
-    fn is_zero(&self) -> bool;
-
-    /// Returns true iff this number is odd.
-    fn is_odd(&self) -> bool;
-
-    /// Returns true iff this number is even.
-    fn is_even(&self) -> bool;
-
-    /// Performs a rightwise bitshift of this number, effectively dividing
-    /// it by 2.
-    fn div2(&mut self);
-
-    /// Performs a rightwise bitshift of this number by some amount.
-    fn shr(&mut self, amt: u32);
-
-    /// Performs a leftwise bitshift of this number, effectively multiplying
-    /// it by 2. Overflow is ignored.
-    fn mul2(&mut self);
-
-    /// Performs a leftwise bitshift of this number by some amount.
-    fn shl(&mut self, amt: u32);
-
-    /// Writes this `PrimeFieldRepr` as a big endian integer.
-    fn write_be<W: Write>(&self, mut writer: W) -> io::Result<()> {
-        use byteorder::{BigEndian, WriteBytesExt};
-
-        for digit in self.as_ref().iter().rev() {
-            writer.write_u64::<BigEndian>(*digit)?;
-        }
-
-        Ok(())
-    }
-
-    /// Reads a big endian integer into this representation.
-    fn read_be<R: Read>(&mut self, mut reader: R) -> io::Result<()> {
-        use byteorder::{BigEndian, ReadBytesExt};
-
-        for digit in self.as_mut().iter_mut().rev() {
-            *digit = reader.read_u64::<BigEndian>()?;
-        }
-
-        Ok(())
-    }
-
-    /// Writes this `PrimeFieldRepr` as a little endian integer.
-    fn write_le<W: Write>(&self, mut writer: W) -> io::Result<()> {
-        use byteorder::{LittleEndian, WriteBytesExt};
-
-        for digit in self.as_ref().iter() {
-            writer.write_u64::<LittleEndian>(*digit)?;
-        }
-
-        Ok(())
-    }
-
-    /// Reads a little endian integer into this representation.
-    fn read_le<R: Read>(&mut self, mut reader: R) -> io::Result<()> {
-        use byteorder::{LittleEndian, ReadBytesExt};
-
-        for digit in self.as_mut().iter_mut() {
-            *digit = reader.read_u64::<LittleEndian>()?;
-        }
-
-        Ok(())
-    }
-}
-
-#[derive(Debug, PartialEq)]
-pub enum LegendreSymbol {
-    Zero = 0,
-    QuadraticResidue = 1,
-    QuadraticNonResidue = -1,
-}
-
-/// An error that may occur when trying to interpret a `PrimeFieldRepr` as a
-/// `PrimeField` element.
-#[derive(Debug)]
-pub enum PrimeFieldDecodingError {
-    /// The encoded value is not in the field
-    NotInField(String),
-}
-
-impl Error for PrimeFieldDecodingError {
-    fn description(&self) -> &str {
-        match *self {
-            PrimeFieldDecodingError::NotInField(..) => "not an element of the field",
-        }
-    }
-}
-
-impl fmt::Display for PrimeFieldDecodingError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-        match *self {
-            PrimeFieldDecodingError::NotInField(ref repr) => {
-                write!(f, "{} is not an element of the field", repr)
-            }
-        }
-    }
-}
-
-/// An error that may occur when trying to decode an `EncodedPoint`.
-#[derive(Debug)]
-pub enum GroupDecodingError {
-    /// The coordinate(s) do not lie on the curve.
-    NotOnCurve,
-    /// The element is not part of the r-order subgroup.
-    NotInSubgroup,
-    /// One of the coordinates could not be decoded
-    CoordinateDecodingError(&'static str, PrimeFieldDecodingError),
-    /// The compression mode of the encoded element was not as expected
-    UnexpectedCompressionMode,
-    /// The encoding contained bits that should not have been set
-    UnexpectedInformation,
-}
-
-impl Error for GroupDecodingError {
-    fn description(&self) -> &str {
-        match *self {
-            GroupDecodingError::NotOnCurve => "coordinate(s) do not lie on the curve",
-            GroupDecodingError::NotInSubgroup => "the element is not part of an r-order subgroup",
-            GroupDecodingError::CoordinateDecodingError(..) => "coordinate(s) could not be decoded",
-            GroupDecodingError::UnexpectedCompressionMode => {
-                "encoding has unexpected compression mode"
-            }
-            GroupDecodingError::UnexpectedInformation => "encoding has unexpected information",
-        }
-    }
-}
-
-impl fmt::Display for GroupDecodingError {
-    fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
-        match *self {
-            GroupDecodingError::CoordinateDecodingError(description, ref err) => {
-                write!(f, "{} decoding error: {}", description, err)
-            }
-            _ => write!(f, "{}", self.description()),
-        }
-    }
-}
-
-/// This represents an element of a prime field.
-pub trait PrimeField: Field {
-    /// The prime field can be converted back and forth into this biginteger
-    /// representation.
-    type Repr: PrimeFieldRepr + From<Self>;
-
-    /// Interpret a string of numbers as a (congruent) prime field element.
-    /// Does not accept unnecessary leading zeroes or a blank string.
-    fn from_str(s: &str) -> Option<Self> {
-        if s.is_empty() {
-            return None;
-        }
-
-        if s == "0" {
-            return Some(Self::zero());
-        }
-
-        let mut res = Self::zero();
-
-        let ten = Self::from_repr(Self::Repr::from(10)).unwrap();
-
-        let mut first_digit = true;
-
-        for c in s.chars() {
-            match c.to_digit(10) {
-                Some(c) => {
-                    if first_digit {
-                        if c == 0 {
-                            return None;
-                        }
-
-                        first_digit = false;
-                    }
-
-                    res.mul_assign(&ten);
-                    res.add_assign(&Self::from_repr(Self::Repr::from(u64::from(c))).unwrap());
-                }
-                None => {
-                    return None;
-                }
-            }
-        }
-
-        Some(res)
-    }
-
-    /// Convert this prime field element into a biginteger representation.
-    fn from_repr(Self::Repr) -> Result<Self, PrimeFieldDecodingError>;
-
-    /// Convert a biginteger representation into a prime field element, if
-    /// the number is an element of the field.
-    fn into_repr(&self) -> Self::Repr;
-
-    /// Returns the field characteristic; the modulus.
-    fn char() -> Self::Repr;
-
-    /// How many bits are needed to represent an element of this field.
-    const NUM_BITS: u32;
-
-    /// How many bits of information can be reliably stored in the field element.
-    const CAPACITY: u32;
-
-    /// Returns the multiplicative generator of `char()` - 1 order. This element
-    /// must also be quadratic nonresidue.
-    fn multiplicative_generator() -> Self;
-
-    /// 2^s * t = `char()` - 1 with t odd.
-    const S: u32;
-
-    /// Returns the 2^s root of unity computed by exponentiating the `multiplicative_generator()`
-    /// by t.
-    fn root_of_unity() -> Self;
-}
-
-#[derive(Debug)]
-pub struct BitIterator<E> {
-    t: E,
-    n: usize,
-}
-
-impl<E: AsRef<[u64]>> BitIterator<E> {
-    pub fn new(t: E) -> Self {
-        let n = t.as_ref().len() * 64;
-
-        BitIterator { t, n }
-    }
-}
-
-impl<E: AsRef<[u64]>> Iterator for BitIterator<E> {
-    type Item = bool;
-
-    fn next(&mut self) -> Option<bool> {
-        if self.n == 0 {
-            None
-        } else {
-            self.n -= 1;
-            let part = self.n / 64;
-            let bit = self.n - (64 * part);
-
-            Some(self.t.as_ref()[part] & (1 << bit) > 0)
-        }
-    }
-}
-
-#[test]
-fn test_bit_iterator() {
-    let mut a = BitIterator::new([0xa953d79b83f6ab59, 0x6dea2059e200bd39]);
-    let expected = "01101101111010100010000001011001111000100000000010111101001110011010100101010011110101111001101110000011111101101010101101011001";
-
-    for e in expected.chars() {
-        assert!(a.next().unwrap() == (e == '1'));
-    }
-
-    assert!(a.next().is_none());
-
-    let expected = "1010010101111110101010000101101011101000011101110101001000011001100100100011011010001011011011010001011011101100110100111011010010110001000011110100110001100110011101101000101100011100100100100100001010011101010111110011101011000011101000111011011101011001";
-
-    let mut a = BitIterator::new([
-        0x429d5f3ac3a3b759,
-        0xb10f4c66768b1c92,
-        0x92368b6d16ecd3b4,
-        0xa57ea85ae8775219,
-    ]);
-
-    for e in expected.chars() {
-        assert!(a.next().unwrap() == (e == '1'));
-    }
-
-    assert!(a.next().is_none());
-}
-
-#[cfg(not(feature = "expose-arith"))]
-use self::arith_impl::*;
-
-#[cfg(feature = "expose-arith")]
-pub use self::arith_impl::*;
-
-#[cfg(feature = "u128-support")]
-mod arith_impl {
-    /// Calculate a - b - borrow, returning the result and modifying
-    /// the borrow value.
-    #[inline(always)]
-    pub fn sbb(a: u64, b: u64, borrow: &mut u64) -> u64 {
-        let tmp = (1u128 << 64) + u128::from(a) - u128::from(b) - u128::from(*borrow);
-
-        *borrow = if tmp >> 64 == 0 { 1 } else { 0 };
-
-        tmp as u64
-    }
-
-    /// Calculate a + b + carry, returning the sum and modifying the
-    /// carry value.
-    #[inline(always)]
-    pub fn adc(a: u64, b: u64, carry: &mut u64) -> u64 {
-        let tmp = u128::from(a) + u128::from(b) + u128::from(*carry);
-
-        *carry = (tmp >> 64) as u64;
-
-        tmp as u64
-    }
-
-    /// Calculate a + (b * c) + carry, returning the least significant digit
-    /// and setting carry to the most significant digit.
-    #[inline(always)]
-    pub fn mac_with_carry(a: u64, b: u64, c: u64, carry: &mut u64) -> u64 {
-        let tmp = (u128::from(a)) + u128::from(b) * u128::from(c) + u128::from(*carry);
-
-        *carry = (tmp >> 64) as u64;
-
-        tmp as u64
-    }
-}
-
-#[cfg(not(feature = "u128-support"))]
-mod arith_impl {
-    #[inline(always)]
-    fn split_u64(i: u64) -> (u64, u64) {
-        (i >> 32, i & 0xFFFFFFFF)
-    }
-
-    #[inline(always)]
-    fn combine_u64(hi: u64, lo: u64) -> u64 {
-        (hi << 32) | lo
-    }
-
-    /// Calculate a - b - borrow, returning the result and modifying
-    /// the borrow value.
-    #[inline(always)]
-    pub fn sbb(a: u64, b: u64, borrow: &mut u64) -> u64 {
-        let (a_hi, a_lo) = split_u64(a);
-        let (b_hi, b_lo) = split_u64(b);
-        let (b, r0) = split_u64((1 << 32) + a_lo - b_lo - *borrow);
-        let (b, r1) = split_u64((1 << 32) + a_hi - b_hi - ((b == 0) as u64));
-
-        *borrow = (b == 0) as u64;
-
-        combine_u64(r1, r0)
-    }
-
-    /// Calculate a + b + carry, returning the sum and modifying the
-    /// carry value.
-    #[inline(always)]
-    pub fn adc(a: u64, b: u64, carry: &mut u64) -> u64 {
-        let (a_hi, a_lo) = split_u64(a);
-        let (b_hi, b_lo) = split_u64(b);
-        let (carry_hi, carry_lo) = split_u64(*carry);
-
-        let (t, r0) = split_u64(a_lo + b_lo + carry_lo);
-        let (t, r1) = split_u64(t + a_hi + b_hi + carry_hi);
-
-        *carry = t;
-
-        combine_u64(r1, r0)
-    }
-
-    /// Calculate a + (b * c) + carry, returning the least significant digit
-    /// and setting carry to the most significant digit.
-    #[inline(always)]
-    pub fn mac_with_carry(a: u64, b: u64, c: u64, carry: &mut u64) -> u64 {
-        /*
-                                [  b_hi  |  b_lo  ]
-                                [  c_hi  |  c_lo  ] *
-        -------------------------------------------
-                                [  b_lo  *  c_lo  ] <-- w
-                       [  b_hi  *  c_lo  ]          <-- x
-                       [  b_lo  *  c_hi  ]          <-- y
-             [   b_hi  *  c_lo  ]                   <-- z
-                                [  a_hi  |  a_lo  ]
-                                [  C_hi  |  C_lo  ]
-        */
-
-        let (a_hi, a_lo) = split_u64(a);
-        let (b_hi, b_lo) = split_u64(b);
-        let (c_hi, c_lo) = split_u64(c);
-        let (carry_hi, carry_lo) = split_u64(*carry);
-
-        let (w_hi, w_lo) = split_u64(b_lo * c_lo);
-        let (x_hi, x_lo) = split_u64(b_hi * c_lo);
-        let (y_hi, y_lo) = split_u64(b_lo * c_hi);
-        let (z_hi, z_lo) = split_u64(b_hi * c_hi);
-
-        let (t, r0) = split_u64(w_lo + a_lo + carry_lo);
-        let (t, r1) = split_u64(t + w_hi + x_lo + y_lo + a_hi + carry_hi);
-        let (t, r2) = split_u64(t + x_hi + y_hi + z_lo);
-        let (_, r3) = split_u64(t + z_hi);
-
-        *carry = combine_u64(r3, r2);
-
-        combine_u64(r1, r0)
-    }
 }

pairing/src/tests/engine.rs

@@ -1,13 +1,18 @@
-use rand::{Rand, SeedableRng, XorShiftRng};
+use group::{CurveAffine, CurveProjective};
+use rand_core::SeedableRng;
+use rand_xorshift::XorShiftRng;
 
-use {CurveAffine, CurveProjective, Engine, Field, PrimeField};
+use {Engine, Field, PairingCurveAffine, PrimeField};
 
 pub fn engine_tests<E: Engine>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..10 {
-        let a = E::G1::rand(&mut rng).into_affine();
+        let a = E::G1::random(&mut rng).into_affine();
-        let b = E::G2::rand(&mut rng).into_affine();
+        let b = E::G2::random(&mut rng).into_affine();
 
         assert!(a.pairing_with(&b) == b.pairing_with(&a));
         assert!(a.pairing_with(&b) == E::pairing(a, b));
@@ -17,10 +22,10 @@ pub fn engine_tests<E: Engine>() {
         let z1 = E::G1Affine::zero().prepare();
         let z2 = E::G2Affine::zero().prepare();
 
-        let a = E::G1::rand(&mut rng).into_affine().prepare();
+        let a = E::G1::random(&mut rng).into_affine().prepare();
-        let b = E::G2::rand(&mut rng).into_affine().prepare();
+        let b = E::G2::random(&mut rng).into_affine().prepare();
-        let c = E::G1::rand(&mut rng).into_affine().prepare();
+        let c = E::G1::random(&mut rng).into_affine().prepare();
-        let d = E::G2::rand(&mut rng).into_affine().prepare();
+        let d = E::G2::random(&mut rng).into_affine().prepare();
 
         assert_eq!(
             E::Fqk::one(),
@@ -48,12 +53,15 @@ pub fn engine_tests<E: Engine>() {
 }
 
 fn random_miller_loop_tests<E: Engine>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     // Exercise the miller loop for a reduced pairing
     for _ in 0..1000 {
-        let a = E::G1::rand(&mut rng);
+        let a = E::G1::random(&mut rng);
-        let b = E::G2::rand(&mut rng);
+        let b = E::G2::random(&mut rng);
 
         let p2 = E::pairing(a, b);
 
@@ -67,10 +75,10 @@ fn random_miller_loop_tests<E: Engine>() {
 
     // Exercise a double miller loop
     for _ in 0..1000 {
-        let a = E::G1::rand(&mut rng);
+        let a = E::G1::random(&mut rng);
-        let b = E::G2::rand(&mut rng);
+        let b = E::G2::random(&mut rng);
-        let c = E::G1::rand(&mut rng);
+        let c = E::G1::random(&mut rng);
-        let d = E::G2::rand(&mut rng);
+        let d = E::G2::random(&mut rng);
 
         let ab = E::pairing(a, b);
         let cd = E::pairing(c, d);
@@ -91,14 +99,17 @@ fn random_miller_loop_tests<E: Engine>() {
 }
 
 fn random_bilinearity_tests<E: Engine>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let a = E::G1::rand(&mut rng);
+        let a = E::G1::random(&mut rng);
-        let b = E::G2::rand(&mut rng);
+        let b = E::G2::random(&mut rng);
 
-        let c = E::Fr::rand(&mut rng);
+        let c = E::Fr::random(&mut rng);
-        let d = E::Fr::rand(&mut rng);
+        let d = E::Fr::random(&mut rng);
 
         let mut ac = a;
         ac.mul_assign(c);

pairing/src/tests/field.rs

@@ -1,12 +1,16 @@
-use rand::{Rng, SeedableRng, XorShiftRng};
+use ff::{Field, LegendreSymbol, PrimeField, SqrtField};
-use {Field, LegendreSymbol, PrimeField, SqrtField};
+use rand_core::{RngCore, SeedableRng};
+use rand_xorshift::XorShiftRng;
 
 pub fn random_frobenius_tests<F: Field, C: AsRef<[u64]>>(characteristic: C, maxpower: usize) {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..100 {
         for i in 0..(maxpower + 1) {
-            let mut a = F::rand(&mut rng);
+            let mut a = F::random(&mut rng);
             let mut b = a;
 
             for _ in 0..i {
@@ -20,10 +24,13 @@ pub fn random_frobenius_tests<F: Field, C: AsRef<[u64]>>(characteristic: C, maxp
 }
 
 pub fn random_sqrt_tests<F: SqrtField>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..10000 {
-        let a = F::rand(&mut rng);
+        let a = F::random(&mut rng);
         let mut b = a;
         b.square();
         assert_eq!(b.legendre(), LegendreSymbol::QuadraticResidue);
@@ -54,7 +61,10 @@ pub fn random_sqrt_tests<F: SqrtField>() {
 }
 
 pub fn random_field_tests<F: Field>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     random_multiplication_tests::<F, _>(&mut rng);
     random_addition_tests::<F, _>(&mut rng);
@@ -76,14 +86,14 @@ pub fn random_field_tests<F: Field>() {
 
     // Multiplication by zero
     {
-        let mut a = F::rand(&mut rng);
+        let mut a = F::random(&mut rng);
         a.mul_assign(&F::zero());
         assert!(a.is_zero());
     }
 
     // Addition by zero
     {
-        let mut a = F::rand(&mut rng);
+        let mut a = F::random(&mut rng);
         let copy = a;
         a.add_assign(&F::zero());
         assert_eq!(a, copy);
@@ -106,10 +116,13 @@ pub fn from_str_tests<F: PrimeField>() {
     }
 
     {
-        let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+        let mut rng = XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
 
         for _ in 0..1000 {
-            let n: u64 = rng.gen();
+            let n = rng.next_u64();
 
             let a = F::from_str(&format!("{}", n)).unwrap();
             let b = F::from_repr(n.into()).unwrap();
@@ -124,11 +137,11 @@ pub fn from_str_tests<F: PrimeField>() {
     assert!(F::from_str("00000000000").is_none());
 }
 
-fn random_multiplication_tests<F: Field, R: Rng>(rng: &mut R) {
+fn random_multiplication_tests<F: Field, R: RngCore>(rng: &mut R) {
     for _ in 0..10000 {
-        let a = F::rand(rng);
+        let a = F::random(rng);
-        let b = F::rand(rng);
+        let b = F::random(rng);
-        let c = F::rand(rng);
+        let c = F::random(rng);
 
         let mut t0 = a; // (a * b) * c
         t0.mul_assign(&b);
@@ -147,11 +160,11 @@ fn random_multiplication_tests<F: Field, R: Rng>(rng: &mut R) {
     }
 }
 
-fn random_addition_tests<F: Field, R: Rng>(rng: &mut R) {
+fn random_addition_tests<F: Field, R: RngCore>(rng: &mut R) {
     for _ in 0..10000 {
-        let a = F::rand(rng);
+        let a = F::random(rng);
-        let b = F::rand(rng);
+        let b = F::random(rng);
-        let c = F::rand(rng);
+        let c = F::random(rng);
 
         let mut t0 = a; // (a + b) + c
         t0.add_assign(&b);
@@ -170,10 +183,10 @@ fn random_addition_tests<F: Field, R: Rng>(rng: &mut R) {
     }
 }
 
-fn random_subtraction_tests<F: Field, R: Rng>(rng: &mut R) {
+fn random_subtraction_tests<F: Field, R: RngCore>(rng: &mut R) {
     for _ in 0..10000 {
-        let a = F::rand(rng);
+        let b = F::random(rng);
-        let b = F::rand(rng);
+        let a = F::random(rng);
 
         let mut t0 = a; // (a - b)
         t0.sub_assign(&b);
@@ -188,9 +201,9 @@ fn random_subtraction_tests<F: Field, R: Rng>(rng: &mut R) {
     }
 }
 
-fn random_negation_tests<F: Field, R: Rng>(rng: &mut R) {
+fn random_negation_tests<F: Field, R: RngCore>(rng: &mut R) {
     for _ in 0..10000 {
-        let a = F::rand(rng);
+        let a = F::random(rng);
         let mut b = a;
         b.negate();
         b.add_assign(&a);
@@ -199,9 +212,9 @@ fn random_negation_tests<F: Field, R: Rng>(rng: &mut R) {
     }
 }
 
-fn random_doubling_tests<F: Field, R: Rng>(rng: &mut R) {
+fn random_doubling_tests<F: Field, R: RngCore>(rng: &mut R) {
     for _ in 0..10000 {
-        let mut a = F::rand(rng);
+        let mut a = F::random(rng);
         let mut b = a;
         a.add_assign(&b);
         b.double();
@@ -210,9 +223,9 @@ fn random_doubling_tests<F: Field, R: Rng>(rng: &mut R) {
     }
 }
 
-fn random_squaring_tests<F: Field, R: Rng>(rng: &mut R) {
+fn random_squaring_tests<F: Field, R: RngCore>(rng: &mut R) {
     for _ in 0..10000 {
-        let mut a = F::rand(rng);
+        let mut a = F::random(rng);
         let mut b = a;
         a.mul_assign(&b);
         b.square();
@@ -221,11 +234,11 @@ fn random_squaring_tests<F: Field, R: Rng>(rng: &mut R) {
     }
 }
 
-fn random_inversion_tests<F: Field, R: Rng>(rng: &mut R) {
+fn random_inversion_tests<F: Field, R: RngCore>(rng: &mut R) {
     assert!(F::zero().inverse().is_none());
 
     for _ in 0..10000 {
-        let mut a = F::rand(rng);
+        let mut a = F::random(rng);
         let b = a.inverse().unwrap(); // probablistically nonzero
         a.mul_assign(&b);
 
@@ -233,14 +246,14 @@ fn random_inversion_tests<F: Field, R: Rng>(rng: &mut R) {
     }
 }
 
-fn random_expansion_tests<F: Field, R: Rng>(rng: &mut R) {
+fn random_expansion_tests<F: Field, R: RngCore>(rng: &mut R) {
     for _ in 0..10000 {
         // Compare (a + b)(c + d) and (a*c + b*c + a*d + b*d)
 
-        let a = F::rand(rng);
+        let a = F::random(rng);
-        let b = F::rand(rng);
+        let b = F::random(rng);
-        let c = F::rand(rng);
+        let c = F::random(rng);
-        let d = F::rand(rng);
+        let d = F::random(rng);
 
         let mut t0 = a;
         t0.add_assign(&b);

pairing/src/tests/mod.rs

@@ -1,4 +1,3 @@
-pub mod curve;
 pub mod engine;
 pub mod field;
 pub mod repr;

pairing/src/tests/repr.rs

@@ -1,21 +1,25 @@
-use rand::{SeedableRng, XorShiftRng};
+use ff::{PrimeField, PrimeFieldRepr};
-use PrimeFieldRepr;
+use rand_core::SeedableRng;
+use rand_xorshift::XorShiftRng;
 
-pub fn random_repr_tests<R: PrimeFieldRepr>() {
+pub fn random_repr_tests<P: PrimeField>() {
-    random_encoding_tests::<R>();
+    random_encoding_tests::<P>();
-    random_shl_tests::<R>();
+    random_shl_tests::<P>();
-    random_shr_tests::<R>();
+    random_shr_tests::<P>();
 }
 
-fn random_encoding_tests<R: PrimeFieldRepr>() {
+fn random_encoding_tests<P: PrimeField>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..1000 {
-        let r = R::rand(&mut rng);
+        let r = P::random(&mut rng).into_repr();
 
         // Big endian
         {
-            let mut rdecoded = R::default();
+            let mut rdecoded = <P as PrimeField>::Repr::default();
 
             let mut v: Vec<u8> = vec![];
             r.write_be(&mut v).unwrap();
@@ -26,7 +30,7 @@ fn random_encoding_tests<R: PrimeFieldRepr>() {
 
         // Little endian
         {
-            let mut rdecoded = R::default();
+            let mut rdecoded = <P as PrimeField>::Repr::default();
 
             let mut v: Vec<u8> = vec![];
             r.write_le(&mut v).unwrap();
@@ -36,8 +40,8 @@ fn random_encoding_tests<R: PrimeFieldRepr>() {
         }
 
         {
-            let mut rdecoded_le = R::default();
+            let mut rdecoded_le = <P as PrimeField>::Repr::default();
-            let mut rdecoded_be_flip = R::default();
+            let mut rdecoded_be_flip = <P as PrimeField>::Repr::default();
 
             let mut v: Vec<u8> = vec![];
             r.write_le(&mut v).unwrap();
@@ -55,11 +59,14 @@ fn random_encoding_tests<R: PrimeFieldRepr>() {
     }
 }
 
-fn random_shl_tests<R: PrimeFieldRepr>() {
+fn random_shl_tests<P: PrimeField>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..100 {
-        let r = R::rand(&mut rng);
+        let r = P::random(&mut rng).into_repr();
 
         for shift in 0..(r.num_bits() + 1) {
             let mut r1 = r;
@@ -76,11 +83,14 @@ fn random_shl_tests<R: PrimeFieldRepr>() {
     }
 }
 
-fn random_shr_tests<R: PrimeFieldRepr>() {
+fn random_shr_tests<P: PrimeField>() {
-    let mut rng = XorShiftRng::from_seed([0x5dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
+    let mut rng = XorShiftRng::from_seed([
+        0x59, 0x62, 0xbe, 0x5d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06, 0xbc,
+        0xe5,
+    ]);
 
     for _ in 0..100 {
-        let r = R::rand(&mut rng);
+        let r = P::random(&mut rng).into_repr();
 
         for shift in 0..(r.num_bits() + 1) {
             let mut r1 = r;

sapling-crypto/COPYRIGHT

@@ -1,14 +0,0 @@
-Copyrights in the "sapling-crypto" library are retained by their contributors. No
-copyright assignment is required to contribute to the "sapling-crypto" library.
-
-The "sapling-crypto" library is licensed under either of
-
- * Apache License, Version 2.0, (see ./LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- * MIT license (see ./LICENSE-MIT or http://opensource.org/licenses/MIT)
-
-at your option.
-
-Unless you explicitly state otherwise, any contribution intentionally
-submitted for inclusion in the work by you, as defined in the Apache-2.0
-license, shall be dual licensed as above, without any additional terms or
-conditions.

sapling-crypto/Cargo.toml

@@ -1,31 +0,0 @@
-[package]
-authors = ["Sean Bowe <sean@z.cash>"]
-description = "Cryptographic library for Zcash Sapling"
-documentation = "https://github.com/zcash-hackworks/sapling"
-homepage = "https://github.com/zcash-hackworks/sapling"
-license = "MIT/Apache-2.0"
-name = "sapling-crypto"
-repository = "https://github.com/zcash-hackworks/sapling"
-version = "0.0.1"
-
-[dependencies.pairing]
-path = "../pairing"
-features = ["expose-arith"]
-
-[dependencies]
-bellman = { path = "../bellman" }
-rand = "0.4"
-digest = "0.7"
-byteorder = "1"
-
-[dependencies.blake2-rfc]
-git = "https://github.com/gtank/blake2-rfc"
-rev = "7a5b5fc99ae483a0043db7547fb79a6fa44b88a9"
-
-[dev-dependencies]
-hex-literal = "0.1"
-rust-crypto = "0.2"
-
-[features]
-default = ["u128-support"]
-u128-support = ["pairing/u128-support"]

sapling-crypto/README.md

@@ -1,23 +0,0 @@
-# sapling-crypto
-
-This repository contains a (work-in-progress) implementation of Zcash's "Sapling" cryptography.
-
-## Security Warnings
-
-This library is currently under development and has not been reviewed.
-
-## License
-
-Licensed under either of
-
- * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
- * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
-
-at your option.
-
-### Contribution
-
-Unless you explicitly state otherwise, any contribution intentionally
-submitted for inclusion in the work by you, as defined in the Apache-2.0
-license, shall be dual licensed as above, without any additional terms or
-conditions.

sapling-crypto/benches/pedersen_hash.rs

@@ -1,23 +0,0 @@
-#![feature(test)]
-
-extern crate rand;
-extern crate test;
-extern crate pairing;
-extern crate sapling_crypto;
-
-use rand::{Rand, thread_rng};
-use pairing::bls12_381::Bls12;
-use sapling_crypto::jubjub::JubjubBls12;
-use sapling_crypto::pedersen_hash::{pedersen_hash, Personalization};
-
-#[bench]
-fn bench_pedersen_hash(b: &mut test::Bencher) {
-    let params = JubjubBls12::new();
-    let rng = &mut thread_rng();
-    let bits = (0..510).map(|_| bool::rand(rng)).collect::<Vec<_>>();
-    let personalization = Personalization::MerkleTree(31);
-
-    b.iter(|| {
-        pedersen_hash::<Bls12, _>(personalization, bits.clone(), &params)
-    });
-}

sapling-crypto/examples/bench.rs

@@ -1,102 +0,0 @@
-extern crate sapling_crypto;
-extern crate bellman;
-extern crate rand;
-extern crate pairing;
-
-use std::time::{Duration, Instant};
-use sapling_crypto::jubjub::{
-    JubjubBls12,
-    edwards,
-    fs,
-};
-use sapling_crypto::circuit::sapling::{
-    Spend
-};
-use sapling_crypto::primitives::{
-    Diversifier,
-    ProofGenerationKey,
-    ValueCommitment
-};
-use bellman::groth16::*;
-use rand::{XorShiftRng, SeedableRng, Rng};
-use pairing::bls12_381::{Bls12, Fr};
-
-const TREE_DEPTH: usize = 32;
-
-fn main() {
-    let jubjub_params = &JubjubBls12::new();
-    let rng = &mut XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
-
-    println!("Creating sample parameters...");
-    let groth_params = generate_random_parameters::<Bls12, _, _>(
-        Spend {
-            params: jubjub_params,
-            value_commitment: None,
-            proof_generation_key: None,
-            payment_address: None,
-            commitment_randomness: None,
-            ar: None,
-            auth_path: vec![None; TREE_DEPTH],
-            anchor: None
-        },
-        rng
-    ).unwrap();
-
-    const SAMPLES: u32 = 50;
-
-    let mut total_time = Duration::new(0, 0);
-    for _ in 0..SAMPLES {
-        let value_commitment = ValueCommitment {
-            value: 1,
-            randomness: rng.gen()
-        };
-
-        let nsk: fs::Fs = rng.gen();
-        let ak = edwards::Point::rand(rng, jubjub_params).mul_by_cofactor(jubjub_params);
-
-        let proof_generation_key = ProofGenerationKey {
-            ak: ak.clone(),
-            nsk: nsk.clone()
-        };
-
-        let viewing_key = proof_generation_key.into_viewing_key(jubjub_params);
-
-        let payment_address;
-
-        loop {
-            let diversifier = Diversifier(rng.gen());
-
-            if let Some(p) = viewing_key.into_payment_address(
-                diversifier,
-                jubjub_params
-            )
-            {
-                payment_address = p;
-                break;
-            }
-        }
-
-        let commitment_randomness: fs::Fs = rng.gen();
-        let auth_path = vec![Some((rng.gen(), rng.gen())); TREE_DEPTH];
-        let ar: fs::Fs = rng.gen();
-        let anchor: Fr = rng.gen();
-
-        let start = Instant::now();
-        let _ = create_random_proof(Spend {
-            params: jubjub_params,
-            value_commitment: Some(value_commitment),
-            proof_generation_key: Some(proof_generation_key),
-            payment_address: Some(payment_address),
-            commitment_randomness: Some(commitment_randomness),
-            ar: Some(ar),
-            auth_path: auth_path,
-            anchor: Some(anchor)
-        }, &groth_params, rng).unwrap();
-        total_time += start.elapsed();
-    }
-    let avg = total_time / SAMPLES;
-    let avg = avg.subsec_nanos() as f64 / 1_000_000_000f64
-              + (avg.as_secs() as f64);
-
-    println!("Average proving time (in seconds): {}", avg);
-}

sapling-crypto/src/circuit/multipack.rs

@@ -1,113 +0,0 @@
-use pairing::{Engine, Field, PrimeField};
-use bellman::{ConstraintSystem, SynthesisError};
-use super::boolean::{Boolean};
-use super::num::Num;
-use super::Assignment;
-
-/// Takes a sequence of booleans and exposes them as compact
-/// public inputs
-pub fn pack_into_inputs<E, CS>(
-    mut cs: CS,
-    bits: &[Boolean]
-) -> Result<(), SynthesisError>
-    where E: Engine, CS: ConstraintSystem<E>
-{
-    for (i, bits) in bits.chunks(E::Fr::CAPACITY as usize).enumerate()
-    {
-        let mut num = Num::<E>::zero();
-        let mut coeff = E::Fr::one();
-        for bit in bits {
-            num = num.add_bool_with_coeff(CS::one(), bit, coeff);
-
-            coeff.double();
-        }
-
-        let input = cs.alloc_input(|| format!("input {}", i), || {
-            Ok(*num.get_value().get()?)
-        })?;
-
-        // num * 1 = input
-        cs.enforce(
-            || format!("packing constraint {}", i),
-            |_| num.lc(E::Fr::one()),
-            |lc| lc + CS::one(),
-            |lc| lc + input
-        );
-    }
-
-    Ok(())
-}
-
-pub fn bytes_to_bits(bytes: &[u8]) -> Vec<bool>
-{
-    bytes.iter()
-         .flat_map(|&v| (0..8).rev().map(move |i| (v >> i) & 1 == 1))
-         .collect()
-}
-
-pub fn bytes_to_bits_le(bytes: &[u8]) -> Vec<bool>
-{
-    bytes.iter()
-         .flat_map(|&v| (0..8).map(move |i| (v >> i) & 1 == 1))
-         .collect()
-}
-
-pub fn compute_multipacking<E: Engine>(
-    bits: &[bool]
-) -> Vec<E::Fr>
-{
-    let mut result = vec![];
-
-    for bits in bits.chunks(E::Fr::CAPACITY as usize)
-    {
-        let mut cur = E::Fr::zero();
-        let mut coeff = E::Fr::one();
-
-        for bit in bits {
-            if *bit {
-                cur.add_assign(&coeff);
-            }
-
-            coeff.double();
-        }
-
-        result.push(cur);
-    }
-
-    result
-}
-
-#[test]
-fn test_multipacking() {
-    use rand::{SeedableRng, Rng, XorShiftRng};
-    use bellman::{ConstraintSystem};
-    use pairing::bls12_381::{Bls12};
-    use ::circuit::test::*;
-    use super::boolean::{AllocatedBit, Boolean};
-
-    let mut rng = XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
-
-    for num_bits in 0..1500 {
-        let mut cs = TestConstraintSystem::<Bls12>::new();
-
-        let bits: Vec<bool> = (0..num_bits).map(|_| rng.gen()).collect();
-
-        let circuit_bits = bits.iter().enumerate()
-                               .map(|(i, &b)| {
-                                   Boolean::from(
-                                     AllocatedBit::alloc(
-                                        cs.namespace(|| format!("bit {}", i)),
-                                        Some(b)
-                                     ).unwrap()
-                                   )
-                               })
-                               .collect::<Vec<_>>();
-
-        let expected_inputs = compute_multipacking::<Bls12>(&bits);
-
-        pack_into_inputs(cs.namespace(|| "pack"), &circuit_bits).unwrap();
-
-        assert!(cs.is_satisfied());
-        assert!(cs.verify(&expected_inputs));
-    }
-}

sapling-crypto/src/circuit/pedersen_hash.rs

@@ -1,194 +0,0 @@
-use super::*;
-use super::ecc::{
-    MontgomeryPoint,
-    EdwardsPoint
-};
-use super::boolean::Boolean;
-use ::jubjub::*;
-use bellman::{
-    ConstraintSystem
-};
-use super::lookup::*;
-pub use pedersen_hash::Personalization;
-
-impl Personalization {
-    fn get_constant_bools(&self) -> Vec<Boolean> {
-        self.get_bits()
-        .into_iter()
-        .map(|e| Boolean::constant(e))
-        .collect()
-    }
-}
-
-pub fn pedersen_hash<E: JubjubEngine, CS>(
-    mut cs: CS,
-    personalization: Personalization,
-    bits: &[Boolean],
-    params: &E::Params
-) -> Result<EdwardsPoint<E>, SynthesisError>
-    where CS: ConstraintSystem<E>
-{
-    let personalization = personalization.get_constant_bools();
-    assert_eq!(personalization.len(), 6);
-
-    let mut edwards_result = None;
-    let mut bits = personalization.iter().chain(bits.iter());
-    let mut segment_generators = params.pedersen_circuit_generators().iter();
-    let boolean_false = Boolean::constant(false);
-
-    let mut segment_i = 0;
-    loop {
-        let mut segment_result = None;
-        let mut segment_windows = &segment_generators.next()
-                                                     .expect("enough segments")[..];
-
-        let mut window_i = 0;
-        while let Some(a) = bits.next() {
-            let b = bits.next().unwrap_or(&boolean_false);
-            let c = bits.next().unwrap_or(&boolean_false);
-
-            let tmp = lookup3_xy_with_conditional_negation(
-                cs.namespace(|| format!("segment {}, window {}", segment_i, window_i)),
-                &[a.clone(), b.clone(), c.clone()],
-                &segment_windows[0]
-            )?;
-
-            let tmp = MontgomeryPoint::interpret_unchecked(tmp.0, tmp.1);
-
-            match segment_result {
-                None => {
-                    segment_result = Some(tmp);
-                },
-                Some(ref mut segment_result) => {
-                    *segment_result = tmp.add(
-                        cs.namespace(|| format!("addition of segment {}, window {}", segment_i, window_i)),
-                        segment_result,
-                        params
-                    )?;
-                }
-            }
-
-            segment_windows = &segment_windows[1..];
-
-            if segment_windows.len() == 0 {
-                break;
-            }
-
-            window_i += 1;
-        }
-
-        match segment_result {
-            Some(segment_result) => {
-                // Convert this segment into twisted Edwards form.
-                let segment_result = segment_result.into_edwards(
-                    cs.namespace(|| format!("conversion of segment {} into edwards", segment_i)),
-                    params
-                )?;
-
-                match edwards_result {
-                    Some(ref mut edwards_result) => {
-                        *edwards_result = segment_result.add(
-                            cs.namespace(|| format!("addition of segment {} to accumulator", segment_i)),
-                            edwards_result,
-                            params
-                        )?;
-                    },
-                    None => {
-                        edwards_result = Some(segment_result);
-                    }
-                }
-            },
-            None => {
-                // We didn't process any new bits.
-                break;
-            }
-        }
-
-        segment_i += 1;
-    }
-
-    Ok(edwards_result.unwrap())
-}
-
-#[cfg(test)]
-mod test {
-    use rand::{SeedableRng, Rng, XorShiftRng};
-    use super::*;
-    use ::circuit::test::*;
-    use ::circuit::boolean::{Boolean, AllocatedBit};
-    use pairing::bls12_381::{Bls12, Fr};
-    use pairing::PrimeField;
-
-    #[test]
-    fn test_pedersen_hash_constraints() {
-        let mut rng = XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
-        let params = &JubjubBls12::new();
-        let mut cs = TestConstraintSystem::<Bls12>::new();
-
-        let input: Vec<bool> = (0..(Fr::NUM_BITS * 2)).map(|_| rng.gen()).collect();
-
-        let input_bools: Vec<Boolean> = input.iter().enumerate().map(|(i, b)| {
-            Boolean::from(
-                AllocatedBit::alloc(cs.namespace(|| format!("input {}", i)), Some(*b)).unwrap()
-            )
-        }).collect();
-
-        pedersen_hash(
-            cs.namespace(|| "pedersen hash"),
-            Personalization::NoteCommitment,
-            &input_bools,
-            params
-        ).unwrap();
-
-        assert!(cs.is_satisfied());
-        assert_eq!(cs.num_constraints(), 1377);
-    }
-
-    #[test]
-    fn test_pedersen_hash() {
-        let mut rng = XorShiftRng::from_seed([0x3dbe6259, 0x8d313d76, 0x3237db17, 0xe5bc0654]);
-        let params = &JubjubBls12::new();
-
-        for length in 0..751 {
-            for _ in 0..5 {
-                let mut input: Vec<bool> = (0..length).map(|_| rng.gen()).collect();
-
-                let mut cs = TestConstraintSystem::<Bls12>::new();
-
-                let input_bools: Vec<Boolean> = input.iter().enumerate().map(|(i, b)| {
-                    Boolean::from(
-                        AllocatedBit::alloc(cs.namespace(|| format!("input {}", i)), Some(*b)).unwrap()
-                    )
-                }).collect();
-
-                let res = pedersen_hash(
-                    cs.namespace(|| "pedersen hash"),
-                    Personalization::MerkleTree(1),
-                    &input_bools,
-                    params
-                ).unwrap();
-
-                assert!(cs.is_satisfied());
-
-                let expected = ::pedersen_hash::pedersen_hash::<Bls12, _>(
-                    Personalization::MerkleTree(1),
-                    input.clone().into_iter(),
-                    params
-                ).into_xy();
-
-                assert_eq!(res.get_x().get_value().unwrap(), expected.0);
-                assert_eq!(res.get_y().get_value().unwrap(), expected.1);
-
-                // Test against the output of a different personalization
-                let unexpected = ::pedersen_hash::pedersen_hash::<Bls12, _>(
-                    Personalization::MerkleTree(0),
-                    input.into_iter(),
-                    params
-                ).into_xy();
-
-                assert!(res.get_x().get_value().unwrap() != unexpected.0);
-                assert!(res.get_y().get_value().unwrap() != unexpected.1);
-            }
-        }
-    }
-}

sapling-crypto/src/lib.rs

@@ -1,22 +0,0 @@
-extern crate pairing;
-extern crate bellman;
-extern crate blake2_rfc;
-extern crate digest;
-extern crate rand;
-extern crate byteorder;
-
-#[cfg(test)]
-#[macro_use]
-extern crate hex_literal;
-
-#[cfg(test)]
-extern crate crypto;
-
-pub mod jubjub;
-pub mod group_hash;
-pub mod circuit;
-pub mod pedersen_hash;
-pub mod primitives;
-pub mod constants;
-pub mod redjubjub;
-pub mod util;

zcash_client_backend/.gitignore

@@ -0,0 +1,2 @@
+# Protobufs
+src/proto/

zcash_client_backend/Cargo.toml

@@ -0,0 +1,25 @@
+[package]
+name = "zcash_client_backend"
+version = "0.0.0"
+authors = [
+    "Jack Grigg <jack@z.cash>",
+]
+edition = "2018"
+
+[dependencies]
+bech32 = "0.7"
+bs58 = { version = "0.2", features = ["check"] }
+ff = { path = "../ff" }
+hex = "0.3"
+pairing = { path = "../pairing" }
+protobuf = "2"
+subtle = "2"
+zcash_primitives = { path = "../zcash_primitives" }
+
+[build-dependencies]
+protobuf-codegen-pure = "2"
+
+[dev-dependencies]
+rand_core = "0.5"
+rand_os = "0.2"
+rand_xorshift = "0.2"

zcash_client_backend/LICENSE-APACHE

@@ -199,3 +199,4 @@ distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
+

zcash_client_backend/LICENSE-MIT

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2017-2019 Electric Coin Company
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

zcash_client_backend/README.md

@@ -1,6 +1,6 @@
-# zcash_wallet
+# zcash_client_backend
 
-This library contains Rust structs and traits for creating shielded Zcash wallets.
+This library contains Rust structs and traits for creating shielded Zcash light clients.
 
 ## License
 

zcash_client_backend/build.rs

@@ -0,0 +1,11 @@
+use protobuf_codegen_pure;
+
+fn main() {
+    protobuf_codegen_pure::run(protobuf_codegen_pure::Args {
+        out_dir: "src/proto",
+        input: &["proto/compact_formats.proto"],
+        includes: &["proto"],
+        customize: Default::default(),
+    })
+    .expect("protoc");
+}

zcash_client_backend/proto/compact_formats.proto

@@ -0,0 +1,48 @@
+syntax = "proto3";
+package cash.z.wallet.sdk.rpc;
+option go_package = "walletrpc";
+
+// Remember that proto3 fields are all optional. A field that is not present will be set to its zero value.
+// bytes fields of hashes are in canonical little-endian format.
+
+// CompactBlock is a packaging of ONLY the data from a block that's needed to:
+//   1. Detect a payment to your shielded Sapling address
+//   2. Detect a spend of your shielded Sapling notes
+//   3. Update your witnesses to generate new Sapling spend proofs.
+message CompactBlock {
+    uint32 protoVersion = 1; // the version of this wire format, for storage
+    uint64 height = 2; // the height of this block
+    bytes hash = 3;
+    bytes prevHash = 4;
+    uint32 time = 5;
+    bytes header = 6; // (hash, prevHash, and time) OR (full header)
+    repeated CompactTx vtx = 7; // compact transactions from this block
+}
+
+message CompactTx {
+    // Index and hash will allow the receiver to call out to chain
+    // explorers or other data structures to retrieve more information
+    // about this transaction.
+    uint64 index = 1;
+    bytes hash = 2;
+
+    // The transaction fee: present if server can provide. In the case of a
+    // stateless server and a transaction with transparent inputs, this will be
+    // unset because the calculation requires reference to prior transactions.
+    // in a pure-Sapling context, the fee will be calculable as:
+    //    valueBalance + (sum(vPubNew) - sum(vPubOld) - sum(tOut))
+    uint32 fee = 3;
+
+    repeated CompactSpend spends = 4;
+    repeated CompactOutput outputs = 5;
+}
+
+message CompactSpend {
+    bytes nf = 1;
+}
+
+message CompactOutput {
+    bytes cmu = 1;
+    bytes epk = 2;
+    bytes ciphertext = 3;
+}

zcash_client_backend/src/constants.rs

@@ -0,0 +1,9 @@
+//! Zcash global and per-network constants.
+
+pub mod mainnet;
+pub mod testnet;
+pub mod regtest;
+
+pub const SPROUT_CONSENSUS_BRANCH_ID: u32 = 0;
+pub const OVERWINTER_CONSENSUS_BRANCH_ID: u32 = 0x5ba8_1b19;
+pub const SAPLING_CONSENSUS_BRANCH_ID: u32 = 0x76b8_09bb;

zcash_client_backend/src/constants/mainnet.rs

@@ -0,0 +1,38 @@
+/// The mainnet coin type for ZEC, as defined by [SLIP 44].
+///
+/// [SLIP 44]: https://github.com/satoshilabs/slips/blob/master/slip-0044.md
+pub const COIN_TYPE: u32 = 141;
+
+/// The HRP for a Bech32-encoded mainnet [`ExtendedSpendingKey`].
+///
+/// Defined in [ZIP 32].
+///
+/// [`ExtendedSpendingKey`]: zcash_primitives::zip32::ExtendedSpendingKey
+/// [ZIP 32]: https://github.com/zcash/zips/blob/master/zip-0032.rst
+pub const HRP_SAPLING_EXTENDED_SPENDING_KEY: &str = "secret-extended-key-main";
+
+/// The HRP for a Bech32-encoded mainnet [`ExtendedFullViewingKey`].
+///
+/// Defined in [ZIP 32].
+///
+/// [`ExtendedFullViewingKey`]: zcash_primitives::zip32::ExtendedFullViewingKey
+/// [ZIP 32]: https://github.com/zcash/zips/blob/master/zip-0032.rst
+pub const HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY: &str = "zxviews";
+
+/// The HRP for a Bech32-encoded mainnet [`PaymentAddress`].
+///
+/// Defined in section 5.6.4 of the [Zcash Protocol Specification].
+///
+/// [`PaymentAddress`]: sapling_crypto::primitives::PaymentAddress
+/// [Zcash Protocol Specification]: https://github.com/zcash/zips/blob/master/protocol/protocol.pdf
+pub const HRP_SAPLING_PAYMENT_ADDRESS: &str = "zs";
+
+/// The prefix for a Base58Check-encoded mainnet [`TransparentAddress::PublicKey`].
+///
+/// [`TransparentAddress::PublicKey`]: zcash_primitives::legacy::TransparentAddress::PublicKey
+pub const B58_PUBKEY_ADDRESS_PREFIX: [u8; 1] = [0x3c];
+
+/// The prefix for a Base58Check-encoded mainnet [`TransparentAddress::Script`].
+///
+/// [`TransparentAddress::Script`]: zcash_primitives::legacy::TransparentAddress::Script
+pub const B58_SCRIPT_ADDRESS_PREFIX: [u8; 1] = [0x55];

zcash_client_backend/src/constants/regtest.rs

@@ -0,0 +1,38 @@
+/// The testnet coin type for ZEC, as defined by [SLIP 44].
+///
+/// [SLIP 44]: https://github.com/satoshilabs/slips/blob/master/slip-0044.md
+pub const COIN_TYPE: u32 = 1;
+
+/// The HRP for a Bech32-encoded testnet [`ExtendedSpendingKey`].
+///
+/// Defined in [ZIP 32].
+///
+/// [`ExtendedSpendingKey`]: zcash_primitives::zip32::ExtendedSpendingKey
+/// [ZIP 32]: https://github.com/zcash/zips/blob/master/zip-0032.rst
+pub const HRP_SAPLING_EXTENDED_SPENDING_KEY: &str = "secret-extended-key-regtest";
+
+/// The HRP for a Bech32-encoded testnet [`ExtendedFullViewingKey`].
+///
+/// Defined in [ZIP 32].
+///
+/// [`ExtendedFullViewingKey`]: zcash_primitives::zip32::ExtendedFullViewingKey
+/// [ZIP 32]: https://github.com/zcash/zips/blob/master/zip-0032.rst
+pub const HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY: &str = "zxviewregtestsapling";
+
+/// The HRP for a Bech32-encoded testnet [`PaymentAddress`].
+///
+/// Defined in section 5.6.4 of the [Zcash Protocol Specification].
+///
+/// [`PaymentAddress`]: sapling_crypto::primitives::PaymentAddress
+/// [Zcash Protocol Specification]: https://github.com/zcash/zips/blob/master/protocol/protocol.pdf
+pub const HRP_SAPLING_PAYMENT_ADDRESS: &str = "zregtestsapling";
+
+/// The prefix for a Base58Check-encoded testnet [`TransparentAddress::PublicKey`].
+///
+/// [`TransparentAddress::PublicKey`]: zcash_primitives::legacy::TransparentAddress::PublicKey
+pub const B58_PUBKEY_ADDRESS_PREFIX: [u8; 2] = [0x1d, 0x25];
+
+/// The prefix for a Base58Check-encoded testnet [`TransparentAddress::Script`].
+///
+/// [`TransparentAddress::Script`]: zcash_primitives::legacy::TransparentAddress::Script
+pub const B58_SCRIPT_ADDRESS_PREFIX: [u8; 2] = [0x1c, 0xba];

zcash_client_backend/src/constants/testnet.rs

@@ -0,0 +1,38 @@
+/// The testnet coin type for ZEC, as defined by [SLIP 44].
+///
+/// [SLIP 44]: https://github.com/satoshilabs/slips/blob/master/slip-0044.md
+pub const COIN_TYPE: u32 = 1;
+
+/// The HRP for a Bech32-encoded testnet [`ExtendedSpendingKey`].
+///
+/// Defined in [ZIP 32].
+///
+/// [`ExtendedSpendingKey`]: zcash_primitives::zip32::ExtendedSpendingKey
+/// [ZIP 32]: https://github.com/zcash/zips/blob/master/zip-0032.rst
+pub const HRP_SAPLING_EXTENDED_SPENDING_KEY: &str = "secret-extended-key-test";
+
+/// The HRP for a Bech32-encoded testnet [`ExtendedFullViewingKey`].
+///
+/// Defined in [ZIP 32].
+///
+/// [`ExtendedFullViewingKey`]: zcash_primitives::zip32::ExtendedFullViewingKey
+/// [ZIP 32]: https://github.com/zcash/zips/blob/master/zip-0032.rst
+pub const HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY: &str = "zxviewtestsapling";
+
+/// The HRP for a Bech32-encoded testnet [`PaymentAddress`].
+///
+/// Defined in section 5.6.4 of the [Zcash Protocol Specification].
+///
+/// [`PaymentAddress`]: sapling_crypto::primitives::PaymentAddress
+/// [Zcash Protocol Specification]: https://github.com/zcash/zips/blob/master/protocol/protocol.pdf
+pub const HRP_SAPLING_PAYMENT_ADDRESS: &str = "ztestsapling";
+
+/// The prefix for a Base58Check-encoded testnet [`TransparentAddress::PublicKey`].
+///
+/// [`TransparentAddress::PublicKey`]: zcash_primitives::legacy::TransparentAddress::PublicKey
+pub const B58_PUBKEY_ADDRESS_PREFIX: [u8; 2] = [0x1d, 0x25];
+
+/// The prefix for a Base58Check-encoded testnet [`TransparentAddress::Script`].
+///
+/// [`TransparentAddress::Script`]: zcash_primitives::legacy::TransparentAddress::Script
+pub const B58_SCRIPT_ADDRESS_PREFIX: [u8; 2] = [0x1c, 0xba];

zcash_client_backend/src/encoding.rs

@@ -0,0 +1,376 @@
+//! Encoding and decoding functions for Zcash key and address structs.
+//!
+//! Human-Readable Prefixes (HRPs) for Bech32 encodings are located in the [`constants`]
+//! module.
+
+use bech32::{self, Error, FromBase32, ToBase32};
+use bs58::{self, decode::DecodeError};
+use pairing::bls12_381::Bls12;
+use std::io::{self, Write};
+use zcash_primitives::{
+    jubjub::edwards,
+    primitives::{Diversifier, PaymentAddress},
+};
+use zcash_primitives::{
+    legacy::TransparentAddress,
+    zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
+    JUBJUB,
+};
+
+fn bech32_encode<F>(hrp: &str, write: F) -> String
+where
+    F: Fn(&mut dyn Write) -> io::Result<()>,
+{
+    let mut data: Vec<u8> = vec![];
+    write(&mut data).expect("Should be able to write to a Vec");
+    bech32::encode(hrp, data.to_base32()).expect("hrp is invalid")
+}
+
+fn bech32_decode<T, F>(hrp: &str, s: &str, read: F) -> Result<Option<T>, Error>
+where
+    F: Fn(Vec<u8>) -> Option<T>,
+{
+    let (decoded_hrp, data) = bech32::decode(s)?;
+    if decoded_hrp == hrp {
+        Vec::<u8>::from_base32(&data).map(|data| read(data))
+    } else {
+        Ok(None)
+    }
+}
+
+/// Writes an [`ExtendedSpendingKey`] as a Bech32-encoded string.
+///
+/// # Examples
+///
+/// ```
+/// use zcash_client_backend::{
+///     constants::testnet::{COIN_TYPE, HRP_SAPLING_EXTENDED_SPENDING_KEY},
+///     encoding::encode_extended_spending_key,
+///     keys::spending_key,
+/// };
+///
+/// let extsk = spending_key(&[0; 32][..], COIN_TYPE, 0);
+/// let encoded = encode_extended_spending_key(HRP_SAPLING_EXTENDED_SPENDING_KEY, &extsk);
+/// ```
+pub fn encode_extended_spending_key(hrp: &str, extsk: &ExtendedSpendingKey) -> String {
+    bech32_encode(hrp, |w| extsk.write(w))
+}
+
+/// Decodes an [`ExtendedSpendingKey`] from a Bech32-encoded string.
+pub fn decode_extended_spending_key(
+    hrp: &str,
+    s: &str,
+) -> Result<Option<ExtendedSpendingKey>, Error> {
+    bech32_decode(hrp, s, |data| ExtendedSpendingKey::read(&data[..]).ok())
+}
+
+/// Writes an [`ExtendedFullViewingKey`] as a Bech32-encoded string.
+///
+/// # Examples
+///
+/// ```
+/// use zcash_client_backend::{
+///     constants::testnet::{COIN_TYPE, HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY},
+///     encoding::encode_extended_full_viewing_key,
+///     keys::spending_key,
+/// };
+/// use zcash_primitives::zip32::ExtendedFullViewingKey;
+///
+/// let extsk = spending_key(&[0; 32][..], COIN_TYPE, 0);
+/// let extfvk = ExtendedFullViewingKey::from(&extsk);
+/// let encoded = encode_extended_full_viewing_key(HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY, &extfvk);
+/// ```
+pub fn encode_extended_full_viewing_key(hrp: &str, extfvk: &ExtendedFullViewingKey) -> String {
+    bech32_encode(hrp, |w| extfvk.write(w))
+}
+
+/// Decodes an [`ExtendedFullViewingKey`] from a Bech32-encoded string.
+pub fn decode_extended_full_viewing_key(
+    hrp: &str,
+    s: &str,
+) -> Result<Option<ExtendedFullViewingKey>, Error> {
+    bech32_decode(hrp, s, |data| ExtendedFullViewingKey::read(&data[..]).ok())
+}
+
+/// Writes a [`PaymentAddress`] as a Bech32-encoded string.
+///
+/// # Examples
+///
+/// ```
+/// use pairing::bls12_381::Bls12;
+/// use rand_core::SeedableRng;
+/// use rand_xorshift::XorShiftRng;
+/// use zcash_client_backend::{
+///     constants::testnet::HRP_SAPLING_PAYMENT_ADDRESS,
+///     encoding::encode_payment_address,
+/// };
+/// use zcash_primitives::{
+///     jubjub::edwards,
+///     primitives::{Diversifier, PaymentAddress},
+///     JUBJUB,
+/// };
+///
+/// let rng = &mut XorShiftRng::from_seed([
+///     0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+///     0xbc, 0xe5,
+/// ]);
+///
+/// let pa = PaymentAddress {
+///     diversifier: Diversifier([0u8; 11]),
+///     pk_d: edwards::Point::<Bls12, _>::rand(rng, &JUBJUB).mul_by_cofactor(&JUBJUB),
+/// };
+///
+/// assert_eq!(
+///     encode_payment_address(HRP_SAPLING_PAYMENT_ADDRESS, &pa),
+///     "ztestsapling1qqqqqqqqqqqqqqqqqrjq05nyfku05msvu49mawhg6kr0wwljahypwyk2h88z6975u563j0ym7pe",
+/// );
+/// ```
+pub fn encode_payment_address(hrp: &str, addr: &PaymentAddress<Bls12>) -> String {
+    bech32_encode(hrp, |w| {
+        w.write_all(&addr.diversifier.0)?;
+        addr.pk_d.write(w)
+    })
+}
+
+/// Decodes a [`PaymentAddress`] from a Bech32-encoded string.
+///
+/// # Examples
+///
+/// ```
+/// use pairing::bls12_381::Bls12;
+/// use rand_core::SeedableRng;
+/// use rand_xorshift::XorShiftRng;
+/// use zcash_client_backend::{
+///     constants::testnet::HRP_SAPLING_PAYMENT_ADDRESS,
+///     encoding::decode_payment_address,
+/// };
+/// use zcash_primitives::{
+///     jubjub::edwards,
+///     primitives::{Diversifier, PaymentAddress},
+///     JUBJUB,
+/// };
+///
+/// let rng = &mut XorShiftRng::from_seed([
+///     0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+///     0xbc, 0xe5,
+/// ]);
+///
+/// let pa = PaymentAddress {
+///     diversifier: Diversifier([0u8; 11]),
+///     pk_d: edwards::Point::<Bls12, _>::rand(rng, &JUBJUB).mul_by_cofactor(&JUBJUB),
+/// };
+///
+/// assert_eq!(
+///     decode_payment_address(
+///         HRP_SAPLING_PAYMENT_ADDRESS,
+///         "ztestsapling1qqqqqqqqqqqqqqqqqrjq05nyfku05msvu49mawhg6kr0wwljahypwyk2h88z6975u563j0ym7pe",
+///     ),
+///     Ok(Some(pa)),
+/// );
+/// ```
+pub fn decode_payment_address(hrp: &str, s: &str) -> Result<Option<PaymentAddress<Bls12>>, Error> {
+    bech32_decode(hrp, s, |data| {
+        let mut diversifier = Diversifier([0; 11]);
+        diversifier.0.copy_from_slice(&data[0..11]);
+        // Check that the diversifier is valid
+        if diversifier.g_d::<Bls12>(&JUBJUB).is_none() {
+            return None;
+        }
+
+        edwards::Point::<Bls12, _>::read(&data[11..], &JUBJUB)
+            .ok()?
+            .as_prime_order(&JUBJUB)
+            .map(|pk_d| PaymentAddress { pk_d, diversifier })
+    })
+}
+
+/// Writes a [`TransparentAddress`] as a Base58Check-encoded string.
+///
+/// # Examples
+///
+/// ```
+/// use zcash_client_backend::{
+///     constants::testnet::{B58_PUBKEY_ADDRESS_PREFIX, B58_SCRIPT_ADDRESS_PREFIX},
+///     encoding::encode_transparent_address,
+/// };
+/// use zcash_primitives::legacy::TransparentAddress;
+///
+/// assert_eq!(
+///     encode_transparent_address(
+///         &B58_PUBKEY_ADDRESS_PREFIX,
+///         &B58_SCRIPT_ADDRESS_PREFIX,
+///         &TransparentAddress::PublicKey([0; 20]),
+///     ),
+///     "tm9iMLAuYMzJ6jtFLcA7rzUmfreGuKvr7Ma",
+/// );
+///
+/// assert_eq!(
+///     encode_transparent_address(
+///         &B58_PUBKEY_ADDRESS_PREFIX,
+///         &B58_SCRIPT_ADDRESS_PREFIX,
+///         &TransparentAddress::Script([0; 20]),
+///     ),
+///     "t26YoyZ1iPgiMEWL4zGUm74eVWfhyDMXzY2",
+/// );
+/// ```
+pub fn encode_transparent_address(
+    pubkey_version: &[u8],
+    script_version: &[u8],
+    addr: &TransparentAddress,
+) -> String {
+    let decoded = match addr {
+        TransparentAddress::PublicKey(key_id) => {
+            let mut decoded = vec![0; pubkey_version.len() + 20];
+            decoded[..pubkey_version.len()].copy_from_slice(pubkey_version);
+            decoded[pubkey_version.len()..].copy_from_slice(key_id);
+            decoded
+        }
+        TransparentAddress::Script(script_id) => {
+            let mut decoded = vec![0; script_version.len() + 20];
+            decoded[..script_version.len()].copy_from_slice(script_version);
+            decoded[script_version.len()..].copy_from_slice(script_id);
+            decoded
+        }
+    };
+    bs58::encode(decoded).with_check().into_string()
+}
+
+/// Decodes a [`TransparentAddress`] from a Base58Check-encoded string.
+///
+/// # Examples
+///
+/// ```
+/// use zcash_client_backend::{
+///     constants::testnet::{B58_PUBKEY_ADDRESS_PREFIX, B58_SCRIPT_ADDRESS_PREFIX},
+///     encoding::decode_transparent_address,
+/// };
+/// use zcash_primitives::legacy::TransparentAddress;
+///
+/// assert_eq!(
+///     decode_transparent_address(
+///         &B58_PUBKEY_ADDRESS_PREFIX,
+///         &B58_SCRIPT_ADDRESS_PREFIX,
+///         "tm9iMLAuYMzJ6jtFLcA7rzUmfreGuKvr7Ma",
+///     ),
+///     Ok(Some(TransparentAddress::PublicKey([0; 20]))),
+/// );
+///
+/// assert_eq!(
+///     decode_transparent_address(
+///         &B58_PUBKEY_ADDRESS_PREFIX,
+///         &B58_SCRIPT_ADDRESS_PREFIX,
+///         "t26YoyZ1iPgiMEWL4zGUm74eVWfhyDMXzY2",
+///     ),
+///     Ok(Some(TransparentAddress::Script([0; 20]))),
+/// );
+/// ```
+pub fn decode_transparent_address(
+    pubkey_version: &[u8],
+    script_version: &[u8],
+    s: &str,
+) -> Result<Option<TransparentAddress>, DecodeError> {
+    let decoded = bs58::decode(s).with_check(None).into_vec()?;
+    if &decoded[..pubkey_version.len()] == pubkey_version {
+        if decoded.len() == pubkey_version.len() + 20 {
+            let mut data = [0; 20];
+            data.copy_from_slice(&decoded[pubkey_version.len()..]);
+            Ok(Some(TransparentAddress::PublicKey(data)))
+        } else {
+            Ok(None)
+        }
+    } else if &decoded[..script_version.len()] == script_version {
+        if decoded.len() == script_version.len() + 20 {
+            let mut data = [0; 20];
+            data.copy_from_slice(&decoded[script_version.len()..]);
+            Ok(Some(TransparentAddress::Script(data)))
+        } else {
+            Ok(None)
+        }
+    } else {
+        Ok(None)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use pairing::bls12_381::Bls12;
+    use rand_core::SeedableRng;
+    use rand_xorshift::XorShiftRng;
+    use zcash_primitives::JUBJUB;
+    use zcash_primitives::{
+        jubjub::edwards,
+        primitives::{Diversifier, PaymentAddress},
+    };
+
+    use super::{decode_payment_address, encode_payment_address};
+    use crate::constants;
+
+    #[test]
+    fn payment_address() {
+        let rng = &mut XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
+
+        let addr = PaymentAddress {
+            diversifier: Diversifier([0u8; 11]),
+            pk_d: edwards::Point::<Bls12, _>::rand(rng, &JUBJUB).mul_by_cofactor(&JUBJUB),
+        };
+
+        let encoded_main =
+            "zs1qqqqqqqqqqqqqqqqqrjq05nyfku05msvu49mawhg6kr0wwljahypwyk2h88z6975u563j8nfaxd";
+        let encoded_test =
+            "ztestsapling1qqqqqqqqqqqqqqqqqrjq05nyfku05msvu49mawhg6kr0wwljahypwyk2h88z6975u563j0ym7pe";
+
+        assert_eq!(
+            encode_payment_address(constants::mainnet::HRP_SAPLING_PAYMENT_ADDRESS, &addr),
+            encoded_main
+        );
+        assert_eq!(
+            decode_payment_address(
+                constants::mainnet::HRP_SAPLING_PAYMENT_ADDRESS,
+                encoded_main
+            )
+            .unwrap(),
+            Some(addr.clone())
+        );
+
+        assert_eq!(
+            encode_payment_address(constants::testnet::HRP_SAPLING_PAYMENT_ADDRESS, &addr),
+            encoded_test
+        );
+        assert_eq!(
+            decode_payment_address(
+                constants::testnet::HRP_SAPLING_PAYMENT_ADDRESS,
+                encoded_test
+            )
+            .unwrap(),
+            Some(addr)
+        );
+    }
+
+    #[test]
+    fn invalid_diversifier() {
+        let rng = &mut XorShiftRng::from_seed([
+            0x59, 0x62, 0xbe, 0x3d, 0x76, 0x3d, 0x31, 0x8d, 0x17, 0xdb, 0x37, 0x32, 0x54, 0x06,
+            0xbc, 0xe5,
+        ]);
+
+        let addr = PaymentAddress {
+            diversifier: Diversifier([1u8; 11]),
+            pk_d: edwards::Point::<Bls12, _>::rand(rng, &JUBJUB).mul_by_cofactor(&JUBJUB),
+        };
+
+        let encoded_main =
+            encode_payment_address(constants::mainnet::HRP_SAPLING_PAYMENT_ADDRESS, &addr);
+
+        assert_eq!(
+            decode_payment_address(
+                constants::mainnet::HRP_SAPLING_PAYMENT_ADDRESS,
+                &encoded_main
+            )
+            .unwrap(),
+            None
+        );
+    }
+}

zcash_client_backend/src/keys.rs

@@ -0,0 +1,24 @@
+//! Helper functions for managing light client key material.
+
+use zcash_primitives::zip32::{ChildIndex, ExtendedSpendingKey};
+
+/// Derives the ZIP 32 [`ExtendedSpendingKey`] for a given coin type and account from the
+/// given seed.
+///
+/// # Examples
+///
+/// ```
+/// use zcash_client_backend::{constants::testnet::COIN_TYPE, keys::spending_key};
+///
+/// let extsk = spending_key(&[0; 32][..], COIN_TYPE, 0);
+/// ```
+pub fn spending_key(seed: &[u8], coin_type: u32, account: u32) -> ExtendedSpendingKey {
+    ExtendedSpendingKey::from_path(
+        &ExtendedSpendingKey::master(&seed),
+        &[
+            ChildIndex::Hardened(32),
+            ChildIndex::Hardened(coin_type),
+            ChildIndex::Hardened(account),
+        ],
+    )
+}

zcash_client_backend/src/lib.rs

@@ -0,0 +1,11 @@
+//! *A crate for implementing Zcash light clients.*
+//!
+//! `zcash_client_backend` contains Rust structs and traits for creating shielded Zcash
+//! light clients.
+
+pub mod constants;
+pub mod encoding;
+pub mod keys;
+pub mod proto;
+pub mod wallet;
+pub mod welding_rig;

zcash_client_backend/src/proto/mod.rs

@@ -0,0 +1,83 @@
+//! Generated code for handling light client protobuf structs.
+
+use ff::{PrimeField, PrimeFieldRepr};
+use pairing::bls12_381::{Bls12, Fr, FrRepr};
+use zcash_primitives::{
+    block::{BlockHash, BlockHeader},
+    jubjub::{edwards, PrimeOrder},
+    JUBJUB,
+};
+
+pub mod compact_formats;
+
+impl compact_formats::CompactBlock {
+    /// Returns the [`BlockHash`] for this block.
+    ///
+    /// # Panics
+    ///
+    /// This function will panic if [`CompactBlock.header`] is not set and
+    /// [`CompactBlock.hash`] is not exactly 32 bytes.
+    ///
+    /// [`CompactBlock.header`]: #structfield.header
+    /// [`CompactBlock.hash`]: #structfield.hash
+    pub fn hash(&self) -> BlockHash {
+        if let Some(header) = self.header() {
+            header.hash()
+        } else {
+            BlockHash::from_slice(&self.hash)
+        }
+    }
+
+    /// Returns the [`BlockHash`] for this block's parent.
+    ///
+    /// # Panics
+    ///
+    /// This function will panic if [`CompactBlock.header`] is not set and
+    /// [`CompactBlock.prevHash`] is not exactly 32 bytes.
+    ///
+    /// [`CompactBlock.header`]: #structfield.header
+    /// [`CompactBlock.prevHash`]: #structfield.prevHash
+    pub fn prev_hash(&self) -> BlockHash {
+        if let Some(header) = self.header() {
+            header.prev_block
+        } else {
+            BlockHash::from_slice(&self.prevHash)
+        }
+    }
+
+    /// Returns the [`BlockHeader`] for this block if present.
+    ///
+    /// A convenience method that parses [`CompactBlock.header`] if present.
+    ///
+    /// [`CompactBlock.header`]: #structfield.header
+    pub fn header(&self) -> Option<BlockHeader> {
+        if self.header.is_empty() {
+            None
+        } else {
+            BlockHeader::read(&self.header[..]).ok()
+        }
+    }
+}
+
+impl compact_formats::CompactOutput {
+    /// Returns the note commitment for this output.
+    ///
+    /// A convenience method that parses [`CompactOutput.cmu`].
+    ///
+    /// [`CompactOutput.cmu`]: #structfield.cmu
+    pub fn cmu(&self) -> Result<Fr, ()> {
+        let mut repr = FrRepr::default();
+        repr.read_le(&self.cmu[..]).map_err(|_| ())?;
+        Fr::from_repr(repr).map_err(|_| ())
+    }
+
+    /// Returns the ephemeral public key for this output.
+    ///
+    /// A convenience method that parses [`CompactOutput.epk`].
+    ///
+    /// [`CompactOutput.epk`]: #structfield.epk
+    pub fn epk(&self) -> Result<edwards::Point<Bls12, PrimeOrder>, ()> {
+        let p = edwards::Point::<Bls12, _>::read(&self.epk[..], &JUBJUB).map_err(|_| ())?;
+        p.as_prime_order(&JUBJUB).ok_or(())
+    }
+}

zcash_client_backend/src/wallet.rs

@@ -0,0 +1,46 @@
+//! Structs representing transaction data scanned from the block chain by a wallet or
+//! light client.
+
+use pairing::bls12_381::{Bls12, Fr};
+use zcash_primitives::{
+    jubjub::{edwards, PrimeOrder},
+    merkle_tree::IncrementalWitness,
+    primitives::{Note, PaymentAddress},
+    sapling::Node,
+    transaction::TxId,
+};
+
+/// A subset of a [`Transaction`] relevant to wallets and light clients.
+///
+/// [`Transaction`]: zcash_primitives::transaction::Transaction
+pub struct WalletTx {
+    pub txid: TxId,
+    pub index: usize,
+    pub num_spends: usize,
+    pub num_outputs: usize,
+    pub shielded_spends: Vec<WalletShieldedSpend>,
+    pub shielded_outputs: Vec<WalletShieldedOutput>,
+}
+
+/// A subset of a [`SpendDescription`] relevant to wallets and light clients.
+///
+/// [`SpendDescription`]: zcash_primitives::transaction::components::SpendDescription
+pub struct WalletShieldedSpend {
+    pub index: usize,
+    pub nf: Vec<u8>,
+    pub account: usize,
+}
+
+/// A subset of an [`OutputDescription`] relevant to wallets and light clients.
+///
+/// [`OutputDescription`]: zcash_primitives::transaction::components::OutputDescription
+pub struct WalletShieldedOutput {
+    pub index: usize,
+    pub cmu: Fr,
+    pub epk: edwards::Point<Bls12, PrimeOrder>,
+    pub account: usize,
+    pub note: Note<Bls12>,
+    pub to: PaymentAddress<Bls12>,
+    pub is_change: bool,
+    pub witness: IncrementalWitness<Node>,
+}

zcash_client_backend/src/welding_rig.rs

@@ -0,0 +1,399 @@
+//! Tools for scanning a compact representation of the Zcash block chain.
+
+use ff::PrimeField;
+use std::collections::HashSet;
+use subtle::{ConditionallySelectable, ConstantTimeEq, CtOption};
+use zcash_primitives::{
+    jubjub::fs::Fs,
+    merkle_tree::{CommitmentTree, IncrementalWitness},
+    note_encryption::try_sapling_compact_note_decryption,
+    sapling::Node,
+    transaction::TxId,
+    zip32::ExtendedFullViewingKey,
+};
+
+use crate::proto::compact_formats::{CompactBlock, CompactOutput};
+use crate::wallet::{WalletShieldedOutput, WalletShieldedSpend, WalletTx};
+
+/// Scans a [`CompactOutput`] with a set of [`ExtendedFullViewingKey`]s.
+///
+/// Returns a [`WalletShieldedOutput`] and corresponding [`IncrementalWitness`] if this
+/// output belongs to any of the given [`ExtendedFullViewingKey`]s.
+///
+/// The given [`CommitmentTree`] and existing [`IncrementalWitness`]es are incremented
+/// with this output's commitment.
+fn scan_output(
+    (index, output): (usize, CompactOutput),
+    ivks: &[Fs],
+    spent_from_accounts: &HashSet<usize>,
+    tree: &mut CommitmentTree<Node>,
+    existing_witnesses: &mut [&mut IncrementalWitness<Node>],
+    block_witnesses: &mut [&mut IncrementalWitness<Node>],
+    new_witnesses: &mut [&mut IncrementalWitness<Node>],
+) -> Option<WalletShieldedOutput> {
+    let cmu = output.cmu().ok()?;
+    let epk = output.epk().ok()?;
+    let ct = output.ciphertext;
+
+    // Increment tree and witnesses
+    let node = Node::new(cmu.into_repr());
+    for witness in existing_witnesses {
+        witness.append(node).unwrap();
+    }
+    for witness in block_witnesses {
+        witness.append(node).unwrap();
+    }
+    for witness in new_witnesses {
+        witness.append(node).unwrap();
+    }
+    tree.append(node).unwrap();
+
+    for (account, ivk) in ivks.iter().enumerate() {
+        let (note, to) = match try_sapling_compact_note_decryption(ivk, &epk, &cmu, &ct) {
+            Some(ret) => ret,
+            None => continue,
+        };
+
+        // A note is marked as "change" if the account that received it
+        // also spent notes in the same transaction. This will catch,
+        // for instance:
+        // - Change created by spending fractions of notes.
+        // - Notes created by consolidation transactions.
+        // - Notes sent from one account to itself.
+        let is_change = spent_from_accounts.contains(&account);
+
+        return Some(WalletShieldedOutput {
+            index,
+            cmu,
+            epk,
+            account,
+            note,
+            to,
+            is_change,
+            witness: IncrementalWitness::from_tree(tree),
+        });
+    }
+    None
+}
+
+/// Scans a [`CompactBlock`] with a set of [`ExtendedFullViewingKey`]s.
+///
+/// Returns a vector of [`WalletTx`]s belonging to any of the given
+/// [`ExtendedFullViewingKey`]s, and the corresponding new [`IncrementalWitness`]es.
+///
+/// The given [`CommitmentTree`] and existing [`IncrementalWitness`]es are
+/// incremented appropriately.
+pub fn scan_block(
+    block: CompactBlock,
+    extfvks: &[ExtendedFullViewingKey],
+    nullifiers: &[(&[u8], usize)],
+    tree: &mut CommitmentTree<Node>,
+    existing_witnesses: &mut [&mut IncrementalWitness<Node>],
+) -> Vec<WalletTx> {
+    let mut wtxs: Vec<WalletTx> = vec![];
+    let ivks: Vec<_> = extfvks.iter().map(|extfvk| extfvk.fvk.vk.ivk()).collect();
+
+    for tx in block.vtx.into_iter() {
+        let num_spends = tx.spends.len();
+        let num_outputs = tx.outputs.len();
+
+        // Check for spent notes
+        // The only step that is not constant-time is the filter() at the end.
+        let shielded_spends: Vec<_> = tx
+            .spends
+            .into_iter()
+            .enumerate()
+            .map(|(index, spend)| {
+                // Find the first tracked nullifier that matches this spend, and produce
+                // a WalletShieldedSpend if there is a match, in constant time.
+                nullifiers
+                    .iter()
+                    .map(|&(nf, account)| CtOption::new(account as u64, nf.ct_eq(&spend.nf[..])))
+                    .fold(CtOption::new(0, 0.into()), |first, next| {
+                        CtOption::conditional_select(&next, &first, first.is_some())
+                    })
+                    .map(|account| WalletShieldedSpend {
+                        index,
+                        nf: spend.nf,
+                        account: account as usize,
+                    })
+            })
+            .filter(|spend| spend.is_some().into())
+            .map(|spend| spend.unwrap())
+            .collect();
+
+        // Collect the set of accounts that were spent from in this transaction
+        let spent_from_accounts: HashSet<_> =
+            shielded_spends.iter().map(|spend| spend.account).collect();
+
+        // Check for incoming notes while incrementing tree and witnesses
+        let mut shielded_outputs: Vec<WalletShieldedOutput> = vec![];
+        {
+            // Grab mutable references to new witnesses from previous transactions
+            // in this block so that we can update them. Scoped so we don't hold
+            // mutable references to wtxs for too long.
+            let mut block_witnesses: Vec<_> = wtxs
+                .iter_mut()
+                .map(|tx| {
+                    tx.shielded_outputs
+                        .iter_mut()
+                        .map(|output| &mut output.witness)
+                })
+                .flatten()
+                .collect();
+
+            for to_scan in tx.outputs.into_iter().enumerate() {
+                // Grab mutable references to new witnesses from previous outputs
+                // in this transaction so that we can update them. Scoped so we
+                // don't hold mutable references to shielded_outputs for too long.
+                let mut new_witnesses: Vec<_> = shielded_outputs
+                    .iter_mut()
+                    .map(|output| &mut output.witness)
+                    .collect();
+
+                if let Some(output) = scan_output(
+                    to_scan,
+                    &ivks,
+                    &spent_from_accounts,
+                    tree,
+                    existing_witnesses,
+                    &mut block_witnesses,
+                    &mut new_witnesses,
+                ) {
+                    shielded_outputs.push(output);
+                }
+            }
+        }
+
+        if !(shielded_spends.is_empty() && shielded_outputs.is_empty()) {
+            let mut txid = TxId([0u8; 32]);
+            txid.0.copy_from_slice(&tx.hash);
+            wtxs.push(WalletTx {
+                txid,
+                index: tx.index as usize,
+                num_spends,
+                num_outputs,
+                shielded_spends,
+                shielded_outputs,
+            });
+        }
+    }
+
+    wtxs
+}
+
+#[cfg(test)]
+mod tests {
+    use ff::{Field, PrimeField, PrimeFieldRepr};
+    use pairing::bls12_381::{Bls12, Fr};
+    use rand_core::RngCore;
+    use rand_os::OsRng;
+    use zcash_primitives::{
+        jubjub::{fs::Fs, FixedGenerators, JubjubParams, ToUniform},
+        merkle_tree::CommitmentTree,
+        note_encryption::{Memo, SaplingNoteEncryption},
+        primitives::Note,
+        transaction::components::Amount,
+        zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
+        JUBJUB,
+    };
+
+    use super::scan_block;
+    use crate::proto::compact_formats::{CompactBlock, CompactOutput, CompactSpend, CompactTx};
+
+    fn random_compact_tx<R: RngCore>(rng: &mut R) -> CompactTx {
+        let fake_nf = {
+            let mut nf = vec![0; 32];
+            rng.fill_bytes(&mut nf);
+            nf
+        };
+        let fake_cmu = {
+            let fake_cmu = Fr::random(rng);
+            let mut bytes = vec![];
+            fake_cmu.into_repr().write_le(&mut bytes).unwrap();
+            bytes
+        };
+        let fake_epk = {
+            let mut buffer = vec![0; 64];
+            rng.fill_bytes(&mut buffer);
+            let fake_esk = Fs::to_uniform(&buffer[..]);
+            let fake_epk = JUBJUB
+                .generator(FixedGenerators::SpendingKeyGenerator)
+                .mul(fake_esk, &JUBJUB);
+            let mut bytes = vec![];
+            fake_epk.write(&mut bytes).unwrap();
+            bytes
+        };
+        let mut cspend = CompactSpend::new();
+        cspend.set_nf(fake_nf);
+        let mut cout = CompactOutput::new();
+        cout.set_cmu(fake_cmu);
+        cout.set_epk(fake_epk);
+        cout.set_ciphertext(vec![0; 52]);
+        let mut ctx = CompactTx::new();
+        let mut txid = vec![0; 32];
+        rng.fill_bytes(&mut txid);
+        ctx.set_hash(txid);
+        ctx.spends.push(cspend);
+        ctx.outputs.push(cout);
+        ctx
+    }
+
+    /// Create a fake CompactBlock at the given height, with a transaction containing a
+    /// single spend of the given nullifier and a single output paying the given address.
+    /// Returns the CompactBlock.
+    fn fake_compact_block(
+        height: i32,
+        nf: [u8; 32],
+        extfvk: ExtendedFullViewingKey,
+        value: Amount,
+        tx_after: bool,
+    ) -> CompactBlock {
+        let to = extfvk.default_address().unwrap().1;
+
+        // Create a fake Note for the account
+        let mut rng = OsRng;
+        let note = Note {
+            g_d: to.diversifier.g_d::<Bls12>(&JUBJUB).unwrap(),
+            pk_d: to.pk_d.clone(),
+            value: value.into(),
+            r: Fs::random(&mut rng),
+        };
+        let encryptor = SaplingNoteEncryption::new(
+            extfvk.fvk.ovk,
+            note.clone(),
+            to.clone(),
+            Memo::default(),
+            &mut rng,
+        );
+        let mut cmu = vec![];
+        note.cm(&JUBJUB).into_repr().write_le(&mut cmu).unwrap();
+        let mut epk = vec![];
+        encryptor.epk().write(&mut epk).unwrap();
+        let enc_ciphertext = encryptor.encrypt_note_plaintext();
+
+        // Create a fake CompactBlock containing the note
+        let mut cb = CompactBlock::new();
+        cb.set_height(height as u64);
+
+        // Add a random Sapling tx before ours
+        {
+            let mut tx = random_compact_tx(&mut rng);
+            tx.index = cb.vtx.len() as u64;
+            cb.vtx.push(tx);
+        }
+
+        let mut cspend = CompactSpend::new();
+        cspend.set_nf(nf.to_vec());
+        let mut cout = CompactOutput::new();
+        cout.set_cmu(cmu);
+        cout.set_epk(epk);
+        cout.set_ciphertext(enc_ciphertext[..52].to_vec());
+        let mut ctx = CompactTx::new();
+        let mut txid = vec![0; 32];
+        rng.fill_bytes(&mut txid);
+        ctx.set_hash(txid);
+        ctx.spends.push(cspend);
+        ctx.outputs.push(cout);
+        ctx.index = cb.vtx.len() as u64;
+        cb.vtx.push(ctx);
+
+        // Optionally add another random Sapling tx after ours
+        if tx_after {
+            let mut tx = random_compact_tx(&mut rng);
+            tx.index = cb.vtx.len() as u64;
+            cb.vtx.push(tx);
+        }
+
+        cb
+    }
+
+    #[test]
+    fn scan_block_with_my_tx() {
+        let extsk = ExtendedSpendingKey::master(&[]);
+        let extfvk = ExtendedFullViewingKey::from(&extsk);
+
+        let cb = fake_compact_block(
+            1,
+            [0; 32],
+            extfvk.clone(),
+            Amount::from_u64(5).unwrap(),
+            false,
+        );
+        assert_eq!(cb.vtx.len(), 2);
+
+        let mut tree = CommitmentTree::new();
+        let txs = scan_block(cb, &[extfvk], &[], &mut tree, &mut []);
+        assert_eq!(txs.len(), 1);
+
+        let tx = &txs[0];
+        assert_eq!(tx.index, 1);
+        assert_eq!(tx.num_spends, 1);
+        assert_eq!(tx.num_outputs, 1);
+        assert_eq!(tx.shielded_spends.len(), 0);
+        assert_eq!(tx.shielded_outputs.len(), 1);
+        assert_eq!(tx.shielded_outputs[0].index, 0);
+        assert_eq!(tx.shielded_outputs[0].account, 0);
+        assert_eq!(tx.shielded_outputs[0].note.value, 5);
+
+        // Check that the witness root matches
+        assert_eq!(tx.shielded_outputs[0].witness.root(), tree.root());
+    }
+
+    #[test]
+    fn scan_block_with_txs_after_my_tx() {
+        let extsk = ExtendedSpendingKey::master(&[]);
+        let extfvk = ExtendedFullViewingKey::from(&extsk);
+
+        let cb = fake_compact_block(
+            1,
+            [0; 32],
+            extfvk.clone(),
+            Amount::from_u64(5).unwrap(),
+            true,
+        );
+        assert_eq!(cb.vtx.len(), 3);
+
+        let mut tree = CommitmentTree::new();
+        let txs = scan_block(cb, &[extfvk], &[], &mut tree, &mut []);
+        assert_eq!(txs.len(), 1);
+
+        let tx = &txs[0];
+        assert_eq!(tx.index, 1);
+        assert_eq!(tx.num_spends, 1);
+        assert_eq!(tx.num_outputs, 1);
+        assert_eq!(tx.shielded_spends.len(), 0);
+        assert_eq!(tx.shielded_outputs.len(), 1);
+        assert_eq!(tx.shielded_outputs[0].index, 0);
+        assert_eq!(tx.shielded_outputs[0].account, 0);
+        assert_eq!(tx.shielded_outputs[0].note.value, 5);
+
+        // Check that the witness root matches
+        assert_eq!(tx.shielded_outputs[0].witness.root(), tree.root());
+    }
+
+    #[test]
+    fn scan_block_with_my_spend() {
+        let extsk = ExtendedSpendingKey::master(&[]);
+        let extfvk = ExtendedFullViewingKey::from(&extsk);
+        let nf = [7; 32];
+        let account = 12;
+
+        let cb = fake_compact_block(1, nf, extfvk, Amount::from_u64(5).unwrap(), false);
+        assert_eq!(cb.vtx.len(), 2);
+
+        let mut tree = CommitmentTree::new();
+        let txs = scan_block(cb, &[], &[(&nf, account)], &mut tree, &mut []);
+        assert_eq!(txs.len(), 1);
+
+        let tx = &txs[0];
+        assert_eq!(tx.index, 1);
+        assert_eq!(tx.num_spends, 1);
+        assert_eq!(tx.num_outputs, 1);
+        assert_eq!(tx.shielded_spends.len(), 1);
+        assert_eq!(tx.shielded_outputs.len(), 0);
+        assert_eq!(tx.shielded_spends[0].index, 0);
+        assert_eq!(tx.shielded_spends[0].nf, nf);
+        assert_eq!(tx.shielded_spends[0].account, account);
+    }
+}

zcash_client_sqlite/Cargo.toml

@@ -0,0 +1,27 @@
+[package]
+name = "zcash_client_sqlite"
+version = "0.0.0"
+authors = [
+    "Jack Grigg <jack@z.cash>",
+]
+edition = "2018"
+
+[dependencies]
+bech32 = "0.7"
+bs58 = { version = "0.2", features = ["check"] }
+ff = { path = "../ff" }
+pairing = { path = "../pairing" }
+protobuf = "2"
+rusqlite = { version = "0.20", features = ["bundled"] }
+time = "0.1"
+zcash_client_backend = { path = "../zcash_client_backend" }
+zcash_primitives = { path = "../zcash_primitives" }
+
+[dev-dependencies]
+rand_core = "0.5"
+rand_os = "0.2"
+tempfile = "3"
+zcash_proofs = { path = "../zcash_proofs" }
+
+[features]
+mainnet = []