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

Reviewed-on: https://git.hush.is/hush/librustzcash/pulls/4
add fee to builder
2024-01-23 14:53:09 +00:00 · 2024-01-22 17:14:06 +01:00 · 2020-03-14 07:00:15 -07:00 · 2019-10-24 01:22:04 +02:00 · 2019-10-24 00:43:57 +02:00 · 2019-10-20 16:03:23 +02:00
36 changed files with 4055 additions and 149 deletions
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,5 +8,6 @@ before_script:
  - rustup component add rustfmt
 script:
  - cargo build --verbose --release --all
  - cargo fmt --all -- --check
  - cargo test --verbose --release --all
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -44,7 +44,7 @@ dependencies = [
 [[package]]
 name = "autocfg"
-version = "0.1.5"
+version = "0.1.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
@@ -57,18 +57,18 @@ name = "bellman"
 version = "0.1.0"
 dependencies = [
 "bit-vec 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "blake2s_simd 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "blake2s_simd 0.5.8 (registry+https://github.com/rust-lang/crates.io-index)",
 "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "crossbeam 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "ff 0.4.0",
- "futures 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "futures 0.1.29 (registry+https://github.com/rust-lang/crates.io-index)",
 "futures-cpupool 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
 "group 0.1.0",
 "hex-literal 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
 "num_cpus 1.10.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "pairing 0.14.2",
 "rand 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_xorshift 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "sha2 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -78,24 +78,29 @@ name = "bit-vec"
 version = "0.4.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "bitflags"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "blake2b_simd"
-version = "0.5.6"
+version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "arrayref 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
 "arrayvec 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
- "constant_time_eq 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "constant_time_eq 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "blake2s_simd"
-version = "0.5.6"
+version = "0.5.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "arrayref 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
 "arrayvec 0.4.11 (registry+https://github.com/rust-lang/crates.io-index)",
- "constant_time_eq 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "constant_time_eq 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -125,6 +130,14 @@ dependencies = [
 "byte-tools 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "bs58"
 version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "sha2 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "byte-tools"
 version = "0.3.1"
@@ -140,10 +153,15 @@ name = "c2-chacha"
 version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "ppv-lite86 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "cc"
 version = "1.0.42"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "cfg-if"
 version = "0.1.9"
@@ -151,7 +169,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "constant_time_eq"
-version = "0.1.3"
+version = "0.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
@@ -185,8 +203,8 @@ name = "directories"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
- "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -194,20 +212,30 @@ name = "fake-simd"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "fallible-iterator"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "fallible-streaming-iterator"
 version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "ff"
 version = "0.4.0"
 dependencies = [
 "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "ff_derive 0.3.0",
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "ff_derive"
 version = "0.3.0"
 dependencies = [
- "num-bigint 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-bigint 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-integer 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 "proc-macro2 0.4.30 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -222,14 +250,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "aes 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "num-bigint 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-bigint 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-integer 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "futures"
-version = "0.1.28"
+version = "0.1.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
@@ -237,7 +265,7 @@ name = "futures-cpupool"
 version = "0.1.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "futures 0.1.28 (registry+https://github.com/rust-lang/crates.io-index)",
+ "futures 0.1.29 (registry+https://github.com/rust-lang/crates.io-index)",
 "num_cpus 1.10.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -246,16 +274,17 @@ name = "generic-array"
 version = "0.12.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "typenum 1.10.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "typenum 1.11.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "getrandom"
-version = "0.1.8"
+version = "0.1.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
 "wasi 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -291,12 +320,12 @@ dependencies = [
 [[package]]
 name = "lazy_static"
-version = "1.3.0"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "libc"
-version = "0.2.61"
+version = "0.2.62"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
@@ -304,19 +333,47 @@ name = "librustzcash"
 version = "0.1.0"
 dependencies = [
 "bellman 0.1.0",
- "blake2b_simd 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "blake2b_simd 0.5.8 (registry+https://github.com/rust-lang/crates.io-index)",
- "blake2s_simd 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "blake2s_simd 0.5.8 (registry+https://github.com/rust-lang/crates.io-index)",
 "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "ff 0.4.0",
- "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
 "pairing 0.14.2",
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_os 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_os 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "zcash_primitives 0.0.0",
 "zcash_proofs 0.0.0",
 ]
 [[package]]
 name = "libsqlite3-sys"
 version = "0.16.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "cc 1.0.42 (registry+https://github.com/rust-lang/crates.io-index)",
 "pkg-config 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)",
 "vcpkg 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "linked-hash-map"
 version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "lru-cache"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "linked-hash-map 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "memchr"
 version = "2.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "nodrop"
 version = "0.1.13"
@@ -324,9 +381,10 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "num-bigint"
-version = "0.2.2"
+version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "autocfg 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-integer 0.1.41 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -336,7 +394,7 @@ name = "num-integer"
 version = "0.1.41"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "autocfg 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "autocfg 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 "num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -345,7 +403,7 @@ name = "num-traits"
 version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "autocfg 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "autocfg 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -353,7 +411,7 @@ name = "num_cpus"
 version = "1.10.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -368,10 +426,15 @@ dependencies = [
 "byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "ff 0.4.0",
 "group 0.1.0",
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_xorshift 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "pkg-config"
 version = "0.3.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "ppv-lite86"
 version = "0.2.5"
@@ -398,6 +461,28 @@ dependencies = [
 "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "protobuf"
 version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "protobuf-codegen"
 version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "protobuf 2.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "protobuf-codegen-pure"
 version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "protobuf 2.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "protobuf-codegen 2.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "quote"
 version = "0.6.13"
@@ -411,10 +496,10 @@ name = "rand"
 version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "getrandom 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "getrandom 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.61 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_chacha 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand_hc 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -424,15 +509,15 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "c2-chacha 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "rand_core"
-version = "0.5.0"
+version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "getrandom 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "getrandom 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -440,16 +525,16 @@ name = "rand_hc"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "rand_os"
-version = "0.2.1"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "getrandom 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "getrandom 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -457,7 +542,52 @@ name = "rand_xorshift"
 version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "rand_core 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "redox_syscall"
 version = "0.1.56"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "remove_dir_all"
 version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "ripemd160"
 version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "block-buffer 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
 "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "opaque-debug 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "rusqlite"
 version = "0.20.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "fallible-iterator 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "fallible-streaming-iterator 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
 "libsqlite3-sys 0.16.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "lru-cache 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "memchr 2.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
 "time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "secp256k1"
 version = "0.15.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "cc 1.0.42 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
@@ -471,6 +601,11 @@ dependencies = [
 "opaque-debug 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "subtle"
 version = "2.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "syn"
 version = "0.14.9"
@@ -481,9 +616,32 @@ dependencies = [
 "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "tempfile"
 version = "3.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "cfg-if 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
 "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
 "rand 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
 "redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)",
 "remove_dir_all 0.5.2 (registry+https://github.com/rust-lang/crates.io-index)",
 "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "time"
 version = "0.1.42"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
 "libc 0.2.62 (registry+https://github.com/rust-lang/crates.io-index)",
 "redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)",
 "winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 [[package]]
 name = "typenum"
-version = "1.10.0"
+version = "1.11.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
@@ -491,9 +649,19 @@ name = "unicode-xid"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "vcpkg"
 version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "wasi"
 version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 [[package]]
 name = "winapi"
-version = "0.3.7"
+version = "0.3.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
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--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,6 +6,7 @@ members = [
    "librustzcash",
    "pairing",
    "zcash_client_backend",
    "zcash_client_sqlite",
    "zcash_primitives",
    "zcash_proofs",
 ]
--- a/zcash_client_backend/.gitignore
+++ b/zcash_client_backend/.gitignore
@@ -0,0 +1,2 @@
 # Protobufs
 src/proto/
--- a/zcash_client_backend/Cargo.toml
+++ b/zcash_client_backend/Cargo.toml
@@ -8,9 +8,18 @@ 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"
--- a/zcash_client_backend/build.rs
+++ b/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");
 }
--- a/zcash_client_backend/proto/compact_formats.proto
+++ b/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;
 }
--- a/zcash_client_backend/src/constants.rs
+++ b/zcash_client_backend/src/constants.rs
@@ -2,3 +2,8 @@
 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;
--- a/zcash_client_backend/src/constants/mainnet.rs
+++ b/zcash_client_backend/src/constants/mainnet.rs
@@ -1,7 +1,7 @@
 /// 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 = 133;
+pub const COIN_TYPE: u32 = 141;
 /// The HRP for a Bech32-encoded mainnet [`ExtendedSpendingKey`].
 ///
@@ -26,3 +26,13 @@ pub const HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY: &str = "zxviews";
 /// [`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];
--- a/zcash_client_backend/src/constants/regtest.rs
+++ b/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];
--- a/zcash_client_backend/src/constants/testnet.rs
+++ b/zcash_client_backend/src/constants/testnet.rs
@@ -26,3 +26,13 @@ pub const HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY: &str = "zxviewtestsapling";
 /// [`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];
--- a/zcash_client_backend/src/encoding.rs
+++ b/zcash_client_backend/src/encoding.rs
@@ -4,6 +4,7 @@
 //! 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::{
@@ -11,6 +12,7 @@ use zcash_primitives::{
    primitives::{Diversifier, PaymentAddress},
 };
 use zcash_primitives::{
    legacy::TransparentAddress,
    zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
    JUBJUB,
 };
@@ -182,6 +184,113 @@ pub fn decode_payment_address(hrp: &str, s: &str) -> Result<Option<PaymentAddres
    })
 }
 /// 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;
--- a/zcash_client_backend/src/lib.rs
+++ b/zcash_client_backend/src/lib.rs
@@ -6,3 +6,6 @@
 pub mod constants;
 pub mod encoding;
 pub mod keys;
 pub mod proto;
 pub mod wallet;
 pub mod welding_rig;
--- a/zcash_client_backend/src/proto/mod.rs
+++ b/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(())
    }
 }
--- a/zcash_client_backend/src/wallet.rs
+++ b/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>,
 }
--- a/zcash_client_backend/src/welding_rig.rs
+++ b/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);
    }
 }
--- a/zcash_client_sqlite/Cargo.toml
+++ b/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 = []
--- a/zcash_client_sqlite/README.md
+++ b/zcash_client_sqlite/README.md
@@ -0,0 +1,60 @@
 # Security Disclaimer
 #### :warning:  WARNING: This is an *early preview*
 ----
 In the spirit of transparency, we provide this as a window into what we are actively
 developing. This is an alpha build, not yet intended for 3rd party use. Please be advised
 of the following:
 * 🛑 This code currently is not audited. 🛑
 * ❌ This is a public, active branch with **no support**.
 * ❌ The code **does not have** documentation that is reviewed and approved by our Documentation team.
 * ❌ The code **does not have** adequate unit tests, acceptance tests and stress tests.
 * ❌ The code **does not have** automated tests that use the officially supported CI system.
 * ❌ The code **has not been subjected to thorough review** by engineers at the Electric Coin Company.
 * :warning: This library **is** compatible with the latest version of zcashd, but there **is no** automated testing of this.
 * :heavy_check_mark: The library **is not** majorly broken in some way.
 * :heavy_check_mark: The library **does run** on mainnet and testnet.
 * ❌ We **are actively rebasing** this branch and adding features where/when needed.
 * ❌ We **do not** undertake appropriate security coverage (threat models, review, response, etc.).
 * :heavy_check_mark: There is a product manager for this library.
 * :heavy_check_mark: Electric Coin Company maintains the library as we discover bugs and do network upgrades/minor releases.
 * :heavy_check_mark: Users can expect to get a response within a few weeks after submitting an issue.
 * ❌ The User Support team **has not yet been briefed** on the features provided to users and the functionality of the associated test-framework.
 * ❌ The code is **not fully-documented**.
 ### 🛑 Use of this code may lead to a loss of funds 🛑
 Use of this code in its current form or with modifications may lead to loss of funds, loss
 of "expected" privacy, or denial of service for a large portion of users, or a bug which
 could leverage any of those kinds of attacks (especially a "0 day" where we suspect few
 people know about the vulnerability).
 ### :eyes: At this time, this is for preview purposes only. :eyes:
 ----
 # zcash_client_sqlite
 This library contains APIs that collectively implement a Zcash light client in
 an SQLite database.
 ## 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.
--- a/zcash_client_sqlite/src/address.rs
+++ b/zcash_client_sqlite/src/address.rs
@@ -0,0 +1,63 @@
 //! Structs for handling supported address types.
 use pairing::bls12_381::Bls12;
 use zcash_client_backend::encoding::{
    decode_payment_address, decode_transparent_address, encode_payment_address,
    encode_transparent_address,
 };
 use zcash_primitives::{legacy::TransparentAddress, primitives::PaymentAddress};
 #[cfg(feature = "mainnet")]
 use zcash_client_backend::constants::mainnet::{
    B58_PUBKEY_ADDRESS_PREFIX, B58_SCRIPT_ADDRESS_PREFIX, HRP_SAPLING_PAYMENT_ADDRESS,
 };
 #[cfg(not(feature = "mainnet"))]
 use zcash_client_backend::constants::testnet::{
    B58_PUBKEY_ADDRESS_PREFIX, B58_SCRIPT_ADDRESS_PREFIX, HRP_SAPLING_PAYMENT_ADDRESS,
 };
 /// An address that funds can be sent to.
 pub enum RecipientAddress {
    Shielded(PaymentAddress<Bls12>),
    Transparent(TransparentAddress),
 }
 impl From<PaymentAddress<Bls12>> for RecipientAddress {
    fn from(addr: PaymentAddress<Bls12>) -> Self {
        RecipientAddress::Shielded(addr)
    }
 }
 impl From<TransparentAddress> for RecipientAddress {
    fn from(addr: TransparentAddress) -> Self {
        RecipientAddress::Transparent(addr)
    }
 }
 impl RecipientAddress {
    pub fn from_str(s: &str) -> Option<Self> {
        if let Ok(Some(pa)) = decode_payment_address(HRP_SAPLING_PAYMENT_ADDRESS, s) {
            Some(pa.into())
        } else if let Ok(Some(addr)) =
            decode_transparent_address(&B58_PUBKEY_ADDRESS_PREFIX, &B58_SCRIPT_ADDRESS_PREFIX, s)
        {
            Some(addr.into())
        } else {
            None
        }
    }
    pub fn to_string(&self) -> String {
        match self {
            RecipientAddress::Shielded(pa) => {
                encode_payment_address(HRP_SAPLING_PAYMENT_ADDRESS, pa)
            }
            RecipientAddress::Transparent(addr) => encode_transparent_address(
                &B58_PUBKEY_ADDRESS_PREFIX,
                &B58_SCRIPT_ADDRESS_PREFIX,
                addr,
            ),
        }
    }
 }
--- a/zcash_client_sqlite/src/chain.rs
+++ b/zcash_client_sqlite/src/chain.rs
@@ -0,0 +1,469 @@
 //! Functions for enforcing chain validity and handling chain reorgs.
 //!
 //! # Examples
 //!
 //! ```
 //! use zcash_client_sqlite::{
 //!     chain::{rewind_to_height, validate_combined_chain},
 //!     error::ErrorKind,
 //!     scan::scan_cached_blocks,
 //! };
 //!
 //! let db_cache = "/path/to/cache.db";
 //! let db_data = "/path/to/data.db";
 //!
 //! // 1) Download new CompactBlocks into db_cache.
 //!
 //! // 2) Run the chain validator on the received blocks.
 //! //
 //! // Given that we assume the server always gives us correct-at-the-time blocks, any
 //! // errors are in the blocks we have previously cached or scanned.
 //! if let Err(e) = validate_combined_chain(&db_cache, &db_data) {
 //!     match e.kind() {
 //!         ErrorKind::InvalidChain(upper_bound, _) => {
 //!             // a) Pick a height to rewind to.
 //!             //
 //!             // This might be informed by some external chain reorg information, or
 //!             // heuristics such as the platform, available bandwidth, size of recent
 //!             // CompactBlocks, etc.
 //!             let rewind_height = upper_bound - 10;
 //!
 //!             // b) Rewind scanned block information.
 //!             rewind_to_height(&db_data, rewind_height);
 //!
 //!             // c) Delete cached blocks from rewind_height onwards.
 //!             //
 //!             // This does imply that assumed-valid blocks will be re-downloaded, but it
 //!             // is also possible that in the intervening time, a chain reorg has
 //!             // occurred that orphaned some of those blocks.
 //!
 //!             // d) If there is some separate thread or service downloading
 //!             // CompactBlocks, tell it to go back and download from rewind_height
 //!             // onwards.
 //!         }
 //!         _ => {
 //!             // Handle other errors.
 //!         }
 //!     }
 //! }
 //!
 //! // 3) Scan (any remaining) cached blocks.
 //! //
 //! // At this point, the cache and scanned data are locally consistent (though not
 //! // necessarily consistent with the latest chain tip - this would be discovered the
 //! // next time this codepath is executed after new blocks are received).
 //! scan_cached_blocks(&db_cache, &db_data);
 //! ```
 use protobuf::parse_from_bytes;
 use rusqlite::{Connection, NO_PARAMS};
 use std::path::Path;
 use zcash_client_backend::proto::compact_formats::CompactBlock;
 use crate::{
    error::{Error, ErrorKind},
    SAPLING_ACTIVATION_HEIGHT,
 };
 #[derive(Debug)]
 pub enum ChainInvalidCause {
    PrevHashMismatch,
 }
 struct CompactBlockRow {
    height: i32,
    data: Vec<u8>,
 }
 /// Checks that the scanned blocks in the data database, when combined with the recent
 /// `CompactBlock`s in the cache database, form a valid chain.
 ///
 /// This function is built on the core assumption that the information provided in the
 /// cache database is more likely to be accurate than the previously-scanned information.
 /// This follows from the design (and trust) assumption that the `lightwalletd` server
 /// provides accurate block information as of the time it was requested.
 ///
 /// Returns:
 /// - `Ok(())` if the combined chain is valid.
 /// - `Err(ErrorKind::InvalidChain(upper_bound, cause))` if the combined chain is invalid.
 ///   `upper_bound` is the height of the highest invalid block (on the assumption that the
 ///   highest block in the cache database is correct).
 /// - `Err(e)` if there was an error during validation unrelated to chain validity.
 ///
 /// This function does not mutate either of the databases.
 pub fn validate_combined_chain<P: AsRef<Path>, Q: AsRef<Path>>(
    db_cache: P,
    db_data: Q,
 ) -> Result<(), Error> {
    let cache = Connection::open(db_cache)?;
    let data = Connection::open(db_data)?;
    // Recall where we synced up to previously.
    // If we have never synced, use Sapling activation height to select all cached CompactBlocks.
    let (have_scanned, last_scanned_height) =
        data.query_row("SELECT MAX(height) FROM blocks", NO_PARAMS, |row| {
            row.get(0)
                .map(|h| (true, h))
                .or(Ok((false, SAPLING_ACTIVATION_HEIGHT - 1)))
        })?;
    // Fetch the CompactBlocks we need to validate
    let mut stmt_blocks = cache
        .prepare("SELECT height, data FROM compactblocks WHERE height > ? ORDER BY height DESC")?;
    let mut rows = stmt_blocks.query_map(&[last_scanned_height], |row| {
        Ok(CompactBlockRow {
            height: row.get(0)?,
            data: row.get(1)?,
        })
    })?;
    // Take the highest cached block as accurate.
    let (mut last_height, mut last_prev_hash) = {
        let assumed_correct = match rows.next() {
            Some(row) => row?,
            None => {
                // No cached blocks, and we've already validated the blocks we've scanned,
                // so there's nothing to validate.
                // TODO: Maybe we still want to check if there are cached blocks that are
                // at heights we previously scanned? Check scanning flow again.
                return Ok(());
            }
        };
        let block: CompactBlock = parse_from_bytes(&assumed_correct.data)?;
        (block.height as i32, block.prev_hash())
    };
    for row in rows {
        let row = row?;
        // Scanned blocks MUST be height-sequential.
        if row.height != (last_height - 1) {
            return Err(Error(ErrorKind::InvalidHeight(last_height - 1, row.height)));
        }
        last_height = row.height;
        let block: CompactBlock = parse_from_bytes(&row.data)?;
        // Cached blocks MUST be hash-chained.
        if block.hash() != last_prev_hash {
            return Err(Error(ErrorKind::InvalidChain(
                last_height,
                ChainInvalidCause::PrevHashMismatch,
            )));
        }
        last_prev_hash = block.prev_hash();
    }
    if have_scanned {
        // Cached blocks MUST hash-chain to the last scanned block.
        let last_scanned_hash = data.query_row(
            "SELECT hash FROM blocks WHERE height = ?",
            &[last_scanned_height],
            |row| row.get::<_, Vec<_>>(0),
        )?;
        if &last_scanned_hash[..] != &last_prev_hash.0[..] {
            return Err(Error(ErrorKind::InvalidChain(
                last_scanned_height,
                ChainInvalidCause::PrevHashMismatch,
            )));
        }
    }
    // All good!
    Ok(())
 }
 /// Rewinds the data database to the given height.
 ///
 /// If the requested height is greater than or equal to the height of the last scanned
 /// block, this function does nothing.
 pub fn rewind_to_height<P: AsRef<Path>>(db_data: P, height: i32) -> Result<(), Error> {
    let data = Connection::open(db_data)?;
    // Recall where we synced up to previously.
    // If we have never synced, use Sapling activation height.
    let last_scanned_height =
        data.query_row("SELECT MAX(height) FROM blocks", NO_PARAMS, |row| {
            row.get(0).or(Ok(SAPLING_ACTIVATION_HEIGHT - 1))
        })?;
    if height >= last_scanned_height {
        // Nothing to do.
        return Ok(());
    }
    // Start an SQL transaction for rewinding.
    data.execute("BEGIN IMMEDIATE", NO_PARAMS)?;
    // Decrement witnesses.
    data.execute("DELETE FROM sapling_witnesses WHERE block > ?", &[height])?;
    // Un-mine transactions.
    data.execute(
        "UPDATE transactions SET block = NULL, tx_index = NULL WHERE block > ?",
        &[height],
    )?;
    // Now that they aren't depended on, delete scanned blocks.
    data.execute("DELETE FROM blocks WHERE height > ?", &[height])?;
    // Commit the SQL transaction, rewinding atomically.
    data.execute("COMMIT", NO_PARAMS)?;
    Ok(())
 }
 #[cfg(test)]
 mod tests {
    use tempfile::NamedTempFile;
    use zcash_primitives::{
        block::BlockHash,
        transaction::components::Amount,
        zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
    };
    use super::{rewind_to_height, validate_combined_chain};
    use crate::{
        error::ErrorKind,
        init::{init_accounts_table, init_cache_database, init_data_database},
        query::get_balance,
        scan::scan_cached_blocks,
        tests::{fake_compact_block, insert_into_cache},
        SAPLING_ACTIVATION_HEIGHT,
    };
    #[test]
    fn valid_chain_states() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Empty chain should be valid
        validate_combined_chain(db_cache, db_data).unwrap();
        // Create a fake CompactBlock sending value to the address
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            Amount::from_u64(5).unwrap(),
        );
        insert_into_cache(db_cache, &cb);
        // Cache-only chain should be valid
        validate_combined_chain(db_cache, db_data).unwrap();
        // Scan the cache
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Data-only chain should be valid
        validate_combined_chain(db_cache, db_data).unwrap();
        // Create a second fake CompactBlock sending more value to the address
        let (cb2, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 1,
            cb.hash(),
            extfvk,
            Amount::from_u64(7).unwrap(),
        );
        insert_into_cache(db_cache, &cb2);
        // Data+cache chain should be valid
        validate_combined_chain(db_cache, db_data).unwrap();
        // Scan the cache again
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Data-only chain should be valid
        validate_combined_chain(db_cache, db_data).unwrap();
    }
    #[test]
    fn invalid_chain_cache_disconnected() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Create some fake CompactBlocks
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            Amount::from_u64(5).unwrap(),
        );
        let (cb2, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 1,
            cb.hash(),
            extfvk.clone(),
            Amount::from_u64(7).unwrap(),
        );
        insert_into_cache(db_cache, &cb);
        insert_into_cache(db_cache, &cb2);
        // Scan the cache
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Data-only chain should be valid
        validate_combined_chain(db_cache, db_data).unwrap();
        // Create more fake CompactBlocks that don't connect to the scanned ones
        let (cb3, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 2,
            BlockHash([1; 32]),
            extfvk.clone(),
            Amount::from_u64(8).unwrap(),
        );
        let (cb4, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 3,
            cb3.hash(),
            extfvk.clone(),
            Amount::from_u64(3).unwrap(),
        );
        insert_into_cache(db_cache, &cb3);
        insert_into_cache(db_cache, &cb4);
        // Data+cache chain should be invalid at the data/cache boundary
        match validate_combined_chain(db_cache, db_data) {
            Err(e) => match e.kind() {
                ErrorKind::InvalidChain(upper_bound, _) => {
                    assert_eq!(*upper_bound, SAPLING_ACTIVATION_HEIGHT + 1)
                }
                _ => panic!(),
            },
            _ => panic!(),
        }
    }
    #[test]
    fn invalid_chain_cache_reorg() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Create some fake CompactBlocks
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            Amount::from_u64(5).unwrap(),
        );
        let (cb2, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 1,
            cb.hash(),
            extfvk.clone(),
            Amount::from_u64(7).unwrap(),
        );
        insert_into_cache(db_cache, &cb);
        insert_into_cache(db_cache, &cb2);
        // Scan the cache
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Data-only chain should be valid
        validate_combined_chain(db_cache, db_data).unwrap();
        // Create more fake CompactBlocks that contain a reorg
        let (cb3, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 2,
            cb2.hash(),
            extfvk.clone(),
            Amount::from_u64(8).unwrap(),
        );
        let (cb4, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 3,
            BlockHash([1; 32]),
            extfvk.clone(),
            Amount::from_u64(3).unwrap(),
        );
        insert_into_cache(db_cache, &cb3);
        insert_into_cache(db_cache, &cb4);
        // Data+cache chain should be invalid inside the cache
        match validate_combined_chain(db_cache, db_data) {
            Err(e) => match e.kind() {
                ErrorKind::InvalidChain(upper_bound, _) => {
                    assert_eq!(*upper_bound, SAPLING_ACTIVATION_HEIGHT + 2)
                }
                _ => panic!(),
            },
            _ => panic!(),
        }
    }
    #[test]
    fn data_db_rewinding() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Account balance should be zero
        assert_eq!(get_balance(db_data, 0).unwrap(), Amount::zero());
        // Create fake CompactBlocks sending value to the address
        let value = Amount::from_u64(5).unwrap();
        let value2 = Amount::from_u64(7).unwrap();
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            value,
        );
        let (cb2, _) = fake_compact_block(SAPLING_ACTIVATION_HEIGHT + 1, cb.hash(), extfvk, value2);
        insert_into_cache(db_cache, &cb);
        insert_into_cache(db_cache, &cb2);
        // Scan the cache
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Account balance should reflect both received notes
        assert_eq!(get_balance(db_data, 0).unwrap(), value + value2);
        // "Rewind" to height of last scanned block
        rewind_to_height(db_data, SAPLING_ACTIVATION_HEIGHT + 1).unwrap();
        // Account balance should be unaltered
        assert_eq!(get_balance(db_data, 0).unwrap(), value + value2);
        // Rewind so that one block is dropped
        rewind_to_height(db_data, SAPLING_ACTIVATION_HEIGHT).unwrap();
        // Account balance should only contain the first received note
        assert_eq!(get_balance(db_data, 0).unwrap(), value);
    }
 }
--- a/zcash_client_sqlite/src/error.rs
+++ b/zcash_client_sqlite/src/error.rs
@@ -0,0 +1,132 @@
 use std::error;
 use std::fmt;
 use zcash_primitives::{
    sapling::Node,
    transaction::{builder, TxId},
 };
 #[derive(Debug)]
 pub enum ErrorKind {
    CorruptedData(&'static str),
    IncorrectHRPExtFVK,
    InsufficientBalance(u64, u64),
    InvalidChain(i32, crate::chain::ChainInvalidCause),
    InvalidExtSK(u32),
    InvalidHeight(i32, i32),
    InvalidMemo(std::str::Utf8Error),
    InvalidNewWitnessAnchor(usize, TxId, i32, Node),
    InvalidNote,
    InvalidWitnessAnchor(i64, i32),
    ScanRequired,
    TableNotEmpty,
    Bech32(bech32::Error),
    Base58(bs58::decode::DecodeError),
    Builder(builder::Error),
    Database(rusqlite::Error),
    Io(std::io::Error),
    Protobuf(protobuf::ProtobufError),
 }
 #[derive(Debug)]
 pub struct Error(pub(crate) ErrorKind);
 impl fmt::Display for Error {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match &self.0 {
            ErrorKind::CorruptedData(reason) => write!(f, "Data DB is corrupted: {}", reason),
            ErrorKind::IncorrectHRPExtFVK => write!(f, "Incorrect HRP for extfvk"),
            ErrorKind::InsufficientBalance(have, need) => write!(
                f,
                "Insufficient balance (have {}, need {} including fee)",
                have, need
            ),
            ErrorKind::InvalidChain(upper_bound, cause) => {
                write!(f, "Invalid chain (upper bound: {}): {:?}", upper_bound, cause)
            }
            ErrorKind::InvalidExtSK(account) => {
                write!(f, "Incorrect ExtendedSpendingKey for account {}", account)
            }
            ErrorKind::InvalidHeight(expected, actual) => write!(
                f,
                "Expected height of next CompactBlock to be {}, but was {}",
                expected, actual
            ),
            ErrorKind::InvalidMemo(e) => write!(f, "{}", e),
            ErrorKind::InvalidNewWitnessAnchor(output, txid, last_height, anchor) => write!(
                f,
                "New witness for output {} in tx {} has incorrect anchor after scanning block {}: {:?}",
                output, txid, last_height, anchor,
            ),
            ErrorKind::InvalidNote => write!(f, "Invalid note"),
            ErrorKind::InvalidWitnessAnchor(id_note, last_height) => write!(
                f,
                "Witness for note {} has incorrect anchor after scanning block {}",
                id_note, last_height
            ),
            ErrorKind::ScanRequired => write!(f, "Must scan blocks first"),
            ErrorKind::TableNotEmpty => write!(f, "Table is not empty"),
            ErrorKind::Bech32(e) => write!(f, "{}", e),
            ErrorKind::Base58(e) => write!(f, "{}", e),
            ErrorKind::Builder(e) => write!(f, "{:?}", e),
            ErrorKind::Database(e) => write!(f, "{}", e),
            ErrorKind::Io(e) => write!(f, "{}", e),
            ErrorKind::Protobuf(e) => write!(f, "{}", e),
        }
    }
 }
 impl error::Error for Error {
    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
        match &self.0 {
            ErrorKind::InvalidMemo(e) => Some(e),
            ErrorKind::Bech32(e) => Some(e),
            ErrorKind::Builder(e) => Some(e),
            ErrorKind::Database(e) => Some(e),
            ErrorKind::Io(e) => Some(e),
            ErrorKind::Protobuf(e) => Some(e),
            _ => None,
        }
    }
 }
 impl From<bech32::Error> for Error {
    fn from(e: bech32::Error) -> Self {
        Error(ErrorKind::Bech32(e))
    }
 }
 impl From<bs58::decode::DecodeError> for Error {
    fn from(e: bs58::decode::DecodeError) -> Self {
        Error(ErrorKind::Base58(e))
    }
 }
 impl From<builder::Error> for Error {
    fn from(e: builder::Error) -> Self {
        Error(ErrorKind::Builder(e))
    }
 }
 impl From<rusqlite::Error> for Error {
    fn from(e: rusqlite::Error) -> Self {
        Error(ErrorKind::Database(e))
    }
 }
 impl From<std::io::Error> for Error {
    fn from(e: std::io::Error) -> Self {
        Error(ErrorKind::Io(e))
    }
 }
 impl From<protobuf::ProtobufError> for Error {
    fn from(e: protobuf::ProtobufError) -> Self {
        Error(ErrorKind::Protobuf(e))
    }
 }
 impl Error {
    pub fn kind(&self) -> &ErrorKind {
        &self.0
    }
 }
--- a/zcash_client_sqlite/src/init.rs
+++ b/zcash_client_sqlite/src/init.rs
@@ -0,0 +1,303 @@
 //! Functions for initializing the various databases.
 use rusqlite::{types::ToSql, Connection, NO_PARAMS};
 use std::path::Path;
 use zcash_client_backend::encoding::encode_extended_full_viewing_key;
 use zcash_primitives::{block::BlockHash, zip32::ExtendedFullViewingKey};
 use crate::{
    address_from_extfvk,
    error::{Error, ErrorKind},
    HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY,
 };
 /// Sets up the internal structure of the cache database.
 ///
 /// # Examples
 ///
 /// ```
 /// use tempfile::NamedTempFile;
 /// use zcash_client_sqlite::init::init_cache_database;
 ///
 /// let data_file = NamedTempFile::new().unwrap();
 /// let db_cache = data_file.path();
 /// init_cache_database(&db_cache).unwrap();
 /// ```
 pub fn init_cache_database<P: AsRef<Path>>(db_cache: P) -> Result<(), Error> {
    let cache = Connection::open(db_cache)?;
    cache.execute(
        "CREATE TABLE IF NOT EXISTS compactblocks (
            height INTEGER PRIMARY KEY,
            data BLOB NOT NULL
        )",
        NO_PARAMS,
    )?;
    Ok(())
 }
 /// Sets up the internal structure of the data database.
 ///
 /// # Examples
 ///
 /// ```
 /// use tempfile::NamedTempFile;
 /// use zcash_client_sqlite::init::init_data_database;
 ///
 /// let data_file = NamedTempFile::new().unwrap();
 /// let db_data = data_file.path();
 /// init_data_database(&db_data).unwrap();
 /// ```
 pub fn init_data_database<P: AsRef<Path>>(db_data: P) -> Result<(), Error> {
    let data = Connection::open(db_data)?;
    data.execute(
        "CREATE TABLE IF NOT EXISTS accounts (
            account INTEGER PRIMARY KEY,
            extfvk TEXT NOT NULL,
            address TEXT NOT NULL
        )",
        NO_PARAMS,
    )?;
    data.execute(
        "CREATE TABLE IF NOT EXISTS blocks (
            height INTEGER PRIMARY KEY,
            hash BLOB NOT NULL,
            time INTEGER NOT NULL,
            sapling_tree BLOB NOT NULL
        )",
        NO_PARAMS,
    )?;
    data.execute(
        "CREATE TABLE IF NOT EXISTS transactions (
            id_tx INTEGER PRIMARY KEY,
            txid BLOB NOT NULL UNIQUE,
            created TEXT,
            block INTEGER,
            tx_index INTEGER,
            expiry_height INTEGER,
            raw BLOB,
            FOREIGN KEY (block) REFERENCES blocks(height)
        )",
        NO_PARAMS,
    )?;
    data.execute(
        "CREATE TABLE IF NOT EXISTS received_notes (
            id_note INTEGER PRIMARY KEY,
            tx INTEGER NOT NULL,
            output_index INTEGER NOT NULL,
            account INTEGER NOT NULL,
            diversifier BLOB NOT NULL,
            value INTEGER NOT NULL,
            rcm BLOB NOT NULL,
            nf BLOB NOT NULL UNIQUE,
            is_change BOOLEAN NOT NULL,
            memo BLOB,
            spent INTEGER,
            FOREIGN KEY (tx) REFERENCES transactions(id_tx),
            FOREIGN KEY (account) REFERENCES accounts(account),
            FOREIGN KEY (spent) REFERENCES transactions(id_tx),
            CONSTRAINT tx_output UNIQUE (tx, output_index)
        )",
        NO_PARAMS,
    )?;
    data.execute(
        "CREATE TABLE IF NOT EXISTS sapling_witnesses (
            id_witness INTEGER PRIMARY KEY,
            note INTEGER NOT NULL,
            block INTEGER NOT NULL,
            witness BLOB NOT NULL,
            FOREIGN KEY (note) REFERENCES received_notes(id_note),
            FOREIGN KEY (block) REFERENCES blocks(height),
            CONSTRAINT witness_height UNIQUE (note, block)
        )",
        NO_PARAMS,
    )?;
    data.execute(
        "CREATE TABLE IF NOT EXISTS sent_notes (
            id_note INTEGER PRIMARY KEY,
            tx INTEGER NOT NULL,
            output_index INTEGER NOT NULL,
            from_account INTEGER NOT NULL,
            address TEXT NOT NULL,
            value INTEGER NOT NULL,
            memo BLOB,
            FOREIGN KEY (tx) REFERENCES transactions(id_tx),
            FOREIGN KEY (from_account) REFERENCES accounts(account),
            CONSTRAINT tx_output UNIQUE (tx, output_index)
        )",
        NO_PARAMS,
    )?;
    Ok(())
 }
 /// Initialises the data database with the given [`ExtendedFullViewingKey`]s.
 ///
 /// The [`ExtendedFullViewingKey`]s are stored internally and used by other APIs such as
 /// [`get_address`], [`scan_cached_blocks`], and [`create_to_address`]. `extfvks` **MUST**
 /// be arranged in account-order; that is, the [`ExtendedFullViewingKey`] for ZIP 32
 /// account `i` **MUST** be at `extfvks[i]`.
 ///
 /// # Examples
 ///
 /// ```
 /// use tempfile::NamedTempFile;
 /// use zcash_client_sqlite::init::{init_accounts_table, init_data_database};
 /// use zcash_primitives::zip32::{ExtendedFullViewingKey, ExtendedSpendingKey};
 ///
 /// let data_file = NamedTempFile::new().unwrap();
 /// let db_data = data_file.path();
 /// init_data_database(&db_data).unwrap();
 ///
 /// let extsk = ExtendedSpendingKey::master(&[]);
 /// let extfvks = [ExtendedFullViewingKey::from(&extsk)];
 /// init_accounts_table(&db_data, &extfvks).unwrap();
 /// ```
 ///
 /// [`get_address`]: crate::query::get_address
 /// [`scan_cached_blocks`]: crate::scan::scan_cached_blocks
 /// [`create_to_address`]: crate::transact::create_to_address
 pub fn init_accounts_table<P: AsRef<Path>>(
    db_data: P,
    extfvks: &[ExtendedFullViewingKey],
 ) -> Result<(), Error> {
    let data = Connection::open(db_data)?;
    let mut empty_check = data.prepare("SELECT * FROM accounts LIMIT 1")?;
    if empty_check.exists(NO_PARAMS)? {
        return Err(Error(ErrorKind::TableNotEmpty));
    }
    // Insert accounts atomically
    data.execute("BEGIN IMMEDIATE", NO_PARAMS)?;
    for (account, extfvk) in extfvks.iter().enumerate() {
        let address = address_from_extfvk(extfvk);
        let extfvk =
            encode_extended_full_viewing_key(HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY, extfvk);
        data.execute(
            "INSERT INTO accounts (account, extfvk, address)
            VALUES (?, ?, ?)",
            &[
                (account as u32).to_sql()?,
                extfvk.to_sql()?,
                address.to_sql()?,
            ],
        )?;
    }
    data.execute("COMMIT", NO_PARAMS)?;
    Ok(())
 }
 /// Initialises the data database with the given block.
 ///
 /// This enables a newly-created database to be immediately-usable, without needing to
 /// synchronise historic blocks.
 ///
 /// # Examples
 ///
 /// ```
 /// use zcash_client_sqlite::init::init_blocks_table;
 /// use zcash_primitives::block::BlockHash;
 ///
 /// // The block height.
 /// let height = 500_000;
 /// // The hash of the block header.
 /// let hash = BlockHash([0; 32]);
 /// // The nTime field from the block header.
 /// let time = 12_3456_7890;
 /// // The serialized Sapling commitment tree as of this block.
 /// // Pre-compute and hard-code, or obtain from a service.
 /// let sapling_tree = &[];
 ///
 /// init_blocks_table("/path/to/data.db", height, hash, time, sapling_tree);
 /// ```
 pub fn init_blocks_table<P: AsRef<Path>>(
    db_data: P,
    height: i32,
    hash: BlockHash,
    time: u32,
    sapling_tree: &[u8],
 ) -> Result<(), Error> {
    let data = Connection::open(db_data)?;
    let mut empty_check = data.prepare("SELECT * FROM blocks LIMIT 1")?;
    if empty_check.exists(NO_PARAMS)? {
        return Err(Error(ErrorKind::TableNotEmpty));
    }
    data.execute(
        "INSERT INTO blocks (height, hash, time, sapling_tree)
        VALUES (?, ?, ?, ?)",
        &[
            height.to_sql()?,
            hash.0.to_sql()?,
            time.to_sql()?,
            sapling_tree.to_sql()?,
        ],
    )?;
    Ok(())
 }
 #[cfg(test)]
 mod tests {
    use tempfile::NamedTempFile;
    use zcash_client_backend::encoding::decode_payment_address;
    use zcash_primitives::{
        block::BlockHash,
        zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
    };
    use super::{init_accounts_table, init_blocks_table, init_data_database};
    use crate::{query::get_address, HRP_SAPLING_PAYMENT_ADDRESS};
    #[test]
    fn init_accounts_table_only_works_once() {
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // We can call the function as many times as we want with no data
        init_accounts_table(&db_data, &[]).unwrap();
        init_accounts_table(&db_data, &[]).unwrap();
        // First call with data should initialise the accounts table
        let extfvks = [ExtendedFullViewingKey::from(&ExtendedSpendingKey::master(
            &[],
        ))];
        init_accounts_table(&db_data, &extfvks).unwrap();
        // Subsequent calls should return an error
        init_accounts_table(&db_data, &[]).unwrap_err();
        init_accounts_table(&db_data, &extfvks).unwrap_err();
    }
    #[test]
    fn init_blocks_table_only_works_once() {
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // First call with data should initialise the blocks table
        init_blocks_table(&db_data, 1, BlockHash([1; 32]), 1, &[]).unwrap();
        // Subsequent calls should return an error
        init_blocks_table(&db_data, 2, BlockHash([2; 32]), 2, &[]).unwrap_err();
    }
    #[test]
    fn init_accounts_table_stores_correct_address() {
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvks = [ExtendedFullViewingKey::from(&extsk)];
        init_accounts_table(&db_data, &extfvks).unwrap();
        // The account's address should be in the data DB
        let addr = get_address(&db_data, 0).unwrap();
        let pa = decode_payment_address(HRP_SAPLING_PAYMENT_ADDRESS, &addr).unwrap();
        assert_eq!(pa.unwrap(), extsk.default_address().unwrap().1);
    }
 }
--- a/zcash_client_sqlite/src/lib.rs
+++ b/zcash_client_sqlite/src/lib.rs
@@ -0,0 +1,262 @@
 //! *An SQLite-based Zcash light client.*
 //!
 //! `zcash_client_backend` contains a set of APIs that collectively implement an
 //! SQLite-based light client for the Zcash network.
 //!
 //! # Design
 //!
 //! The light client is built around two SQLite databases:
 //!
 //! - A cache database, used to inform the light client about new [`CompactBlock`]s. It is
 //!   read-only within all light client APIs *except* for [`init_cache_database`] which
 //!   can be used to initialize the database.
 //!
 //! - A data database, where the light client's state is stored. It is read-write within
 //!   the light client APIs, and **assumed to be read-only outside these APIs**. Callers
 //!   **MUST NOT** write to the database without using these APIs. Callers **MAY** read
 //!   the database directly in order to extract information for display to users.
 //!
 //! # Features
 //!
 //! The `mainnet` feature configures the light client for use with the Zcash mainnet. By
 //! default, the light client is configured for use with the Zcash testnet.
 //!
 //! [`CompactBlock`]: zcash_client_backend::proto::compact_formats::CompactBlock
 //! [`init_cache_database`]: crate::init::init_cache_database
 use rusqlite::{Connection, NO_PARAMS};
 use std::cmp;
 use zcash_client_backend::encoding::encode_payment_address;
 use zcash_primitives::zip32::ExtendedFullViewingKey;
 #[cfg(feature = "mainnet")]
 use zcash_client_backend::constants::mainnet::{
    HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY, HRP_SAPLING_PAYMENT_ADDRESS,
 };
 #[cfg(not(feature = "mainnet"))]
 use zcash_client_backend::constants::testnet::{
    HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY, HRP_SAPLING_PAYMENT_ADDRESS,
 };
 pub mod address;
 pub mod chain;
 pub mod error;
 pub mod init;
 pub mod query;
 pub mod scan;
 pub mod transact;
 const ANCHOR_OFFSET: u32 = 10;
 #[cfg(feature = "mainnet")]
 const SAPLING_ACTIVATION_HEIGHT: i32 = 227_520;
 #[cfg(not(feature = "mainnet"))]
 const SAPLING_ACTIVATION_HEIGHT: i32 = 280_000;
 fn address_from_extfvk(extfvk: &ExtendedFullViewingKey) -> String {
    let addr = extfvk.default_address().unwrap().1;
    encode_payment_address(HRP_SAPLING_PAYMENT_ADDRESS, &addr)
 }
 /// Determines the target height for a transaction, and the height from which to
 /// select anchors, based on the current synchronised block chain.
 fn get_target_and_anchor_heights(data: &Connection) -> Result<(u32, u32), error::Error> {
    data.query_row_and_then(
        "SELECT MIN(height), MAX(height) FROM blocks",
        NO_PARAMS,
        |row| match (row.get::<_, u32>(0), row.get::<_, u32>(1)) {
            // If there are no blocks, the query returns NULL.
            (Err(rusqlite::Error::InvalidColumnType(_, _, _)), _)
            | (_, Err(rusqlite::Error::InvalidColumnType(_, _, _))) => {
                Err(error::Error(error::ErrorKind::ScanRequired))
            }
            (Err(e), _) | (_, Err(e)) => Err(e.into()),
            (Ok(min_height), Ok(max_height)) => {
                let target_height = max_height + 1;
                // Select an anchor ANCHOR_OFFSET back from the target block,
                // unless that would be before the earliest block we have.
                let anchor_height =
                    cmp::max(target_height.saturating_sub(ANCHOR_OFFSET), min_height);
                Ok((target_height, anchor_height))
            }
        },
    )
 }
 #[cfg(test)]
 mod tests {
    use ff::{Field, PrimeField, PrimeFieldRepr};
    use pairing::bls12_381::Bls12;
    use protobuf::Message;
    use rand_core::RngCore;
    use rand_os::OsRng;
    use rusqlite::{types::ToSql, Connection};
    use std::path::Path;
    use zcash_client_backend::proto::compact_formats::{
        CompactBlock, CompactOutput, CompactSpend, CompactTx,
    };
    use zcash_primitives::{
        block::BlockHash,
        jubjub::fs::Fs,
        note_encryption::{Memo, SaplingNoteEncryption},
        primitives::{Note, PaymentAddress},
        transaction::components::Amount,
        zip32::ExtendedFullViewingKey,
        JUBJUB,
    };
    /// Create a fake CompactBlock at the given height, containing a single output paying
    /// the given address. Returns the CompactBlock and the nullifier for the new note.
    pub(crate) fn fake_compact_block(
        height: i32,
        prev_hash: BlockHash,
        extfvk: ExtendedFullViewingKey,
        value: Amount,
    ) -> (CompactBlock, Vec<u8>) {
        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 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.outputs.push(cout);
        let mut cb = CompactBlock::new();
        cb.set_height(height as u64);
        cb.hash.resize(32, 0);
        rng.fill_bytes(&mut cb.hash);
        cb.prevHash.extend_from_slice(&prev_hash.0);
        cb.vtx.push(ctx);
        (cb, note.nf(&extfvk.fvk.vk, 0, &JUBJUB))
    }
    /// Create a fake CompactBlock at the given height, spending a single note from the
    /// given address.
    pub(crate) fn fake_compact_block_spending(
        height: i32,
        prev_hash: BlockHash,
        (nf, in_value): (Vec<u8>, Amount),
        extfvk: ExtendedFullViewingKey,
        to: PaymentAddress<Bls12>,
        value: Amount,
    ) -> CompactBlock {
        let mut rng = OsRng;
        // Create a fake CompactBlock containing the note
        let mut cspend = CompactSpend::new();
        cspend.set_nf(nf);
        let mut ctx = CompactTx::new();
        let mut txid = vec![0; 32];
        rng.fill_bytes(&mut txid);
        ctx.set_hash(txid);
        ctx.spends.push(cspend);
        // Create a fake Note for the payment
        ctx.outputs.push({
            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,
                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();
            let mut cout = CompactOutput::new();
            cout.set_cmu(cmu);
            cout.set_epk(epk);
            cout.set_ciphertext(enc_ciphertext[..52].to_vec());
            cout
        });
        // Create a fake Note for the change
        ctx.outputs.push({
            let change_addr = extfvk.default_address().unwrap().1;
            let note = Note {
                g_d: change_addr.diversifier.g_d::<Bls12>(&JUBJUB).unwrap(),
                pk_d: change_addr.pk_d.clone(),
                value: (in_value - value).into(),
                r: Fs::random(&mut rng),
            };
            let encryptor = SaplingNoteEncryption::new(
                extfvk.fvk.ovk,
                note.clone(),
                change_addr,
                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();
            let mut cout = CompactOutput::new();
            cout.set_cmu(cmu);
            cout.set_epk(epk);
            cout.set_ciphertext(enc_ciphertext[..52].to_vec());
            cout
        });
        let mut cb = CompactBlock::new();
        cb.set_height(height as u64);
        cb.hash.resize(32, 0);
        rng.fill_bytes(&mut cb.hash);
        cb.prevHash.extend_from_slice(&prev_hash.0);
        cb.vtx.push(ctx);
        cb
    }
    /// Insert a fake CompactBlock into the cache DB.
    pub(crate) fn insert_into_cache<P: AsRef<Path>>(db_cache: P, cb: &CompactBlock) {
        let cb_bytes = cb.write_to_bytes().unwrap();
        let cache = Connection::open(&db_cache).unwrap();
        cache
            .prepare("INSERT INTO compactblocks (height, data) VALUES (?, ?)")
            .unwrap()
            .execute(&[
                (cb.height as i32).to_sql().unwrap(),
                cb_bytes.to_sql().unwrap(),
            ])
            .unwrap();
    }
 }
--- a/zcash_client_sqlite/src/query.rs
+++ b/zcash_client_sqlite/src/query.rs
@@ -0,0 +1,201 @@
 //! Functions for querying information in the data database.
 use rusqlite::Connection;
 use std::path::Path;
 use zcash_primitives::{note_encryption::Memo, transaction::components::Amount};
 use crate::{
    error::{Error, ErrorKind},
    get_target_and_anchor_heights,
 };
 /// Returns the address for the account.
 ///
 /// # Examples
 ///
 /// ```
 /// use zcash_client_sqlite::query::get_address;
 ///
 /// let addr = get_address("/path/to/data.db", 0);
 /// ```
 pub fn get_address<P: AsRef<Path>>(db_data: P, account: u32) -> Result<String, Error> {
    let data = Connection::open(db_data)?;
    let addr = data.query_row(
        "SELECT address FROM accounts
        WHERE account = ?",
        &[account],
        |row| row.get(0),
    )?;
    Ok(addr)
 }
 /// Returns the balance for the account, including all mined unspent notes that we know
 /// about.
 ///
 /// # Examples
 ///
 /// ```
 /// use zcash_client_sqlite::query::get_balance;
 ///
 /// let addr = get_balance("/path/to/data.db", 0);
 /// ```
 pub fn get_balance<P: AsRef<Path>>(db_data: P, account: u32) -> Result<Amount, Error> {
    let data = Connection::open(db_data)?;
    let balance = data.query_row(
        "SELECT SUM(value) FROM received_notes
        INNER JOIN transactions ON transactions.id_tx = received_notes.tx
        WHERE account = ? AND spent IS NULL AND transactions.block IS NOT NULL",
        &[account],
        |row| row.get(0).or(Ok(0)),
    )?;
    match Amount::from_i64(balance) {
        Ok(amount) if !amount.is_negative() => Ok(amount),
        _ => Err(Error(ErrorKind::CorruptedData(
            "Sum of values in received_notes is out of range",
        ))),
    }
 }
 /// Returns the verified balance for the account, which ignores notes that have been
 /// received too recently and are not yet deemed spendable.
 ///
 /// # Examples
 ///
 /// ```
 /// use zcash_client_sqlite::query::get_verified_balance;
 ///
 /// let addr = get_verified_balance("/path/to/data.db", 0);
 /// ```
 pub fn get_verified_balance<P: AsRef<Path>>(db_data: P, account: u32) -> Result<Amount, Error> {
    let data = Connection::open(db_data)?;
    let (_, anchor_height) = get_target_and_anchor_heights(&data)?;
    let balance = data.query_row(
        "SELECT SUM(value) FROM received_notes
        INNER JOIN transactions ON transactions.id_tx = received_notes.tx
        WHERE account = ? AND spent IS NULL AND transactions.block <= ?",
        &[account, anchor_height],
        |row| row.get(0).or(Ok(0)),
    )?;
    match Amount::from_i64(balance) {
        Ok(amount) if !amount.is_negative() => Ok(amount),
        _ => Err(Error(ErrorKind::CorruptedData(
            "Sum of values in received_notes is out of range",
        ))),
    }
 }
 /// Returns the memo for a received note, if it is known and a valid UTF-8 string.
 ///
 /// The note is identified by its row index in the `received_notes` table within the data
 /// database.
 ///
 /// # Examples
 ///
 /// ```
 /// use zcash_client_sqlite::query::get_received_memo_as_utf8;
 ///
 /// let memo = get_received_memo_as_utf8("/path/to/data.db", 27);
 pub fn get_received_memo_as_utf8<P: AsRef<Path>>(
    db_data: P,
    id_note: i64,
 ) -> Result<Option<String>, Error> {
    let data = Connection::open(db_data)?;
    let memo: Vec<_> = data.query_row(
        "SELECT memo FROM received_notes
        WHERE id_note = ?",
        &[id_note],
        |row| row.get(0),
    )?;
    match Memo::from_bytes(&memo) {
        Some(memo) => match memo.to_utf8() {
            Some(Ok(res)) => Ok(Some(res)),
            Some(Err(e)) => Err(Error(ErrorKind::InvalidMemo(e))),
            None => Ok(None),
        },
        None => Ok(None),
    }
 }
 /// Returns the memo for a sent note, if it is known and a valid UTF-8 string.
 ///
 /// The note is identified by its row index in the `sent_notes` table within the data
 /// database.
 ///
 /// # Examples
 ///
 /// ```
 /// use zcash_client_sqlite::query::get_sent_memo_as_utf8;
 ///
 /// let memo = get_sent_memo_as_utf8("/path/to/data.db", 12);
 pub fn get_sent_memo_as_utf8<P: AsRef<Path>>(
    db_data: P,
    id_note: i64,
 ) -> Result<Option<String>, Error> {
    let data = Connection::open(db_data)?;
    let memo: Vec<_> = data.query_row(
        "SELECT memo FROM sent_notes
        WHERE id_note = ?",
        &[id_note],
        |row| row.get(0),
    )?;
    match Memo::from_bytes(&memo) {
        Some(memo) => match memo.to_utf8() {
            Some(Ok(res)) => Ok(Some(res)),
            Some(Err(e)) => Err(Error(ErrorKind::InvalidMemo(e))),
            None => Ok(None),
        },
        None => Ok(None),
    }
 }
 #[cfg(test)]
 mod tests {
    use tempfile::NamedTempFile;
    use zcash_primitives::{
        transaction::components::Amount,
        zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
    };
    use super::{get_address, get_balance, get_verified_balance};
    use crate::{
        error::ErrorKind,
        init::{init_accounts_table, init_data_database},
    };
    #[test]
    fn empty_database_has_no_balance() {
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvks = [ExtendedFullViewingKey::from(&extsk)];
        init_accounts_table(&db_data, &extfvks).unwrap();
        // The account should be empty
        assert_eq!(get_balance(db_data, 0).unwrap(), Amount::zero());
        // The account should have no verified balance, as we haven't scanned any blocks
        let e = get_verified_balance(db_data, 0).unwrap_err();
        match e.kind() {
            ErrorKind::ScanRequired => (),
            _ => panic!("Unexpected error: {:?}", e),
        }
        // An invalid account has zero balance
        assert!(get_address(db_data, 1).is_err());
        assert_eq!(get_balance(db_data, 1).unwrap(), Amount::zero());
    }
 }
--- a/zcash_client_sqlite/src/scan.rs
+++ b/zcash_client_sqlite/src/scan.rs
@@ -0,0 +1,500 @@
 //! Functions for scanning the chain and extracting relevant information.
 use ff::{PrimeField, PrimeFieldRepr};
 use protobuf::parse_from_bytes;
 use rusqlite::{types::ToSql, Connection, NO_PARAMS};
 use std::path::Path;
 use zcash_client_backend::{
    encoding::decode_extended_full_viewing_key, proto::compact_formats::CompactBlock,
    welding_rig::scan_block,
 };
 use zcash_primitives::{
    merkle_tree::{CommitmentTree, IncrementalWitness},
    sapling::Node,
    JUBJUB,
 };
 use crate::{
    error::{Error, ErrorKind},
    HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY, SAPLING_ACTIVATION_HEIGHT,
 };
 struct CompactBlockRow {
    height: i32,
    data: Vec<u8>,
 }
 #[derive(Clone)]
 struct WitnessRow {
    id_note: i64,
    witness: IncrementalWitness<Node>,
 }
 /// Scans new blocks added to the cache for any transactions received by the tracked
 /// accounts.
 ///
 /// This function pays attention only to cached blocks with heights greater than the
 /// highest scanned block in `db_data`. Cached blocks with lower heights are not verified
 /// against previously-scanned blocks. In particular, this function **assumes** that the
 /// caller is handling rollbacks.
 ///
 /// For brand-new light client databases, this function starts scanning from the Sapling
 /// activation height. This height can be fast-forwarded to a more recent block by calling
 /// [`init_blocks_table`] before this function.
 ///
 /// Scanned blocks are required to be height-sequential. If a block is missing from the
 /// cache, an error will be returned with kind [`ErrorKind::InvalidHeight`].
 ///
 /// # Examples
 ///
 /// ```
 /// use zcash_client_sqlite::scan::scan_cached_blocks;
 ///
 /// scan_cached_blocks("/path/to/cache.db", "/path/to/data.db");
 /// ```
 ///
 /// [`init_blocks_table`]: crate::init::init_blocks_table
 pub fn scan_cached_blocks<P: AsRef<Path>, Q: AsRef<Path>>(
    db_cache: P,
    db_data: Q,
 ) -> Result<(), Error> {
    let cache = Connection::open(db_cache)?;
    let data = Connection::open(db_data)?;
    // Recall where we synced up to previously.
    // If we have never synced, use sapling activation height to select all cached CompactBlocks.
    let mut last_height = data.query_row("SELECT MAX(height) FROM blocks", NO_PARAMS, |row| {
        row.get(0).or(Ok(SAPLING_ACTIVATION_HEIGHT - 1))
    })?;
    // Fetch the CompactBlocks we need to scan
    let mut stmt_blocks = cache
        .prepare("SELECT height, data FROM compactblocks WHERE height > ? ORDER BY height ASC")?;
    let rows = stmt_blocks.query_map(&[last_height], |row| {
        Ok(CompactBlockRow {
            height: row.get(0)?,
            data: row.get(1)?,
        })
    })?;
    // Fetch the ExtendedFullViewingKeys we are tracking
    let mut stmt_fetch_accounts =
        data.prepare("SELECT extfvk FROM accounts ORDER BY account ASC")?;
    let extfvks = stmt_fetch_accounts.query_map(NO_PARAMS, |row| {
        row.get(0).map(|extfvk: String| {
            decode_extended_full_viewing_key(HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY, &extfvk)
        })
    })?;
    // Raise SQL errors from the query, IO errors from parsing, and incorrect HRP errors.
    let extfvks: Vec<_> = extfvks
        .collect::<Result<Result<Option<_>, _>, _>>()??
        .ok_or(Error(ErrorKind::IncorrectHRPExtFVK))?;
    // Get the most recent CommitmentTree
    let mut stmt_fetch_tree = data.prepare("SELECT sapling_tree FROM blocks WHERE height = ?")?;
    let mut tree = stmt_fetch_tree
        .query_row(&[last_height], |row| {
            row.get(0).map(|data: Vec<_>| {
                CommitmentTree::read(&data[..]).unwrap_or_else(|_| CommitmentTree::new())
            })
        })
        .unwrap_or_else(|_| CommitmentTree::new());
    // Get most recent incremental witnesses for the notes we are tracking
    let mut stmt_fetch_witnesses =
        data.prepare("SELECT note, witness FROM sapling_witnesses WHERE block = ?")?;
    let witnesses = stmt_fetch_witnesses.query_map(&[last_height], |row| {
        let id_note = row.get(0)?;
        let data: Vec<_> = row.get(1)?;
        Ok(IncrementalWitness::read(&data[..]).map(|witness| WitnessRow { id_note, witness }))
    })?;
    let mut witnesses: Vec<_> = witnesses.collect::<Result<Result<_, _>, _>>()??;
    // Get the nullifiers for the notes we are tracking
    let mut stmt_fetch_nullifiers =
        data.prepare("SELECT id_note, nf, account FROM received_notes WHERE spent IS NULL")?;
    let nullifiers = stmt_fetch_nullifiers.query_map(NO_PARAMS, |row| {
        let nf: Vec<_> = row.get(1)?;
        let account: i64 = row.get(2)?;
        Ok((nf, account as usize))
    })?;
    let mut nullifiers: Vec<_> = nullifiers.collect::<Result<_, _>>()?;
    // Prepare per-block SQL statements
    let mut stmt_insert_block = data.prepare(
        "INSERT INTO blocks (height, hash, time, sapling_tree)
        VALUES (?, ?, ?, ?)",
    )?;
    let mut stmt_update_tx = data.prepare(
        "UPDATE transactions
        SET block = ?, tx_index = ? WHERE txid = ?",
    )?;
    let mut stmt_insert_tx = data.prepare(
        "INSERT INTO transactions (txid, block, tx_index)
        VALUES (?, ?, ?)",
    )?;
    let mut stmt_select_tx = data.prepare("SELECT id_tx FROM transactions WHERE txid = ?")?;
    let mut stmt_mark_spent_note =
        data.prepare("UPDATE received_notes SET spent = ? WHERE nf = ?")?;
    let mut stmt_insert_note = data.prepare(
        "INSERT INTO received_notes (tx, output_index, account, diversifier, value, rcm, nf, is_change)
        VALUES (?, ?, ?, ?, ?, ?, ?, ?)",
    )?;
    let mut stmt_insert_witness = data.prepare(
        "INSERT INTO sapling_witnesses (note, block, witness)
        VALUES (?, ?, ?)",
    )?;
    let mut stmt_prune_witnesses = data.prepare("DELETE FROM sapling_witnesses WHERE block < ?")?;
    let mut stmt_update_expired = data.prepare(
        "UPDATE received_notes SET spent = NULL WHERE EXISTS (
            SELECT id_tx FROM transactions
            WHERE id_tx = received_notes.spent AND block IS NULL AND expiry_height < ?
        )",
    )?;
    for row in rows {
        let row = row?;
        // Start an SQL transaction for this block.
        data.execute("BEGIN IMMEDIATE", NO_PARAMS)?;
        // Scanned blocks MUST be height-sequential.
        if row.height != (last_height + 1) {
            return Err(Error(ErrorKind::InvalidHeight(last_height + 1, row.height)));
        }
        last_height = row.height;
        let block: CompactBlock = parse_from_bytes(&row.data)?;
        let block_hash = block.hash.clone();
        let block_time = block.time;
        let txs = {
            let nf_refs: Vec<_> = nullifiers.iter().map(|(nf, acc)| (&nf[..], *acc)).collect();
            let mut witness_refs: Vec<_> = witnesses.iter_mut().map(|w| &mut w.witness).collect();
            scan_block(
                block,
                &extfvks[..],
                &nf_refs,
                &mut tree,
                &mut witness_refs[..],
            )
        };
        // Enforce that all roots match. This is slow, so only include in debug builds.
        #[cfg(debug_assertions)]
        {
            let cur_root = tree.root();
            for row in &witnesses {
                if row.witness.root() != cur_root {
                    return Err(Error(ErrorKind::InvalidWitnessAnchor(
                        row.id_note,
                        last_height,
                    )));
                }
            }
            for tx in &txs {
                for output in tx.shielded_outputs.iter() {
                    if output.witness.root() != cur_root {
                        return Err(Error(ErrorKind::InvalidNewWitnessAnchor(
                            output.index,
                            tx.txid,
                            last_height,
                            output.witness.root(),
                        )));
                    }
                }
            }
        }
        // Insert the block into the database.
        let mut encoded_tree = Vec::new();
        tree.write(&mut encoded_tree)
            .expect("Should be able to write to a Vec");
        stmt_insert_block.execute(&[
            row.height.to_sql()?,
            block_hash.to_sql()?,
            block_time.to_sql()?,
            encoded_tree.to_sql()?,
        ])?;
        for tx in txs {
            // First try update an existing transaction in the database.
            let txid = tx.txid.0.to_vec();
            let tx_row = if stmt_update_tx.execute(&[
                row.height.to_sql()?,
                (tx.index as i64).to_sql()?,
                txid.to_sql()?,
            ])? == 0
            {
                // It isn't there, so insert our transaction into the database.
                stmt_insert_tx.execute(&[
                    txid.to_sql()?,
                    row.height.to_sql()?,
                    (tx.index as i64).to_sql()?,
                ])?;
                data.last_insert_rowid()
            } else {
                // It was there, so grab its row number.
                stmt_select_tx.query_row(&[txid], |row| row.get(0))?
            };
            // Mark notes as spent and remove them from the scanning cache
            for spend in &tx.shielded_spends {
                stmt_mark_spent_note.execute(&[tx_row.to_sql()?, spend.nf.to_sql()?])?;
            }
            nullifiers = nullifiers
                .into_iter()
                .filter(|(nf, _acc)| {
                    tx.shielded_spends
                        .iter()
                        .find(|spend| &spend.nf == nf)
                        .is_none()
                })
                .collect();
            for output in tx.shielded_outputs {
                let mut rcm = [0; 32];
                output.note.r.into_repr().write_le(&mut rcm[..])?;
                let nf = output.note.nf(
                    &extfvks[output.account].fvk.vk,
                    output.witness.position() as u64,
                    &JUBJUB,
                );
                // Insert received note into the database.
                // Assumptions:
                // - A transaction will not contain more than 2^63 shielded outputs.
                // - A note value will never exceed 2^63 zatoshis.
                stmt_insert_note.execute(&[
                    tx_row.to_sql()?,
                    (output.index as i64).to_sql()?,
                    (output.account as i64).to_sql()?,
                    output.to.diversifier.0.to_sql()?,
                    (output.note.value as i64).to_sql()?,
                    rcm.to_sql()?,
                    nf.to_sql()?,
                    output.is_change.to_sql()?,
                ])?;
                let note_row = data.last_insert_rowid();
                // Save witness for note.
                witnesses.push(WitnessRow {
                    id_note: note_row,
                    witness: output.witness,
                });
                // Cache nullifier for note (to detect subsequent spends in this scan).
                nullifiers.push((nf, output.account));
            }
        }
        // Insert current witnesses into the database.
        let mut encoded = Vec::new();
        for witness_row in witnesses.iter() {
            encoded.clear();
            witness_row
                .witness
                .write(&mut encoded)
                .expect("Should be able to write to a Vec");
            stmt_insert_witness.execute(&[
                witness_row.id_note.to_sql()?,
                last_height.to_sql()?,
                encoded.to_sql()?,
            ])?;
        }
        // Prune the stored witnesses (we only expect rollbacks of at most 100 blocks).
        stmt_prune_witnesses.execute(&[last_height - 100])?;
        // Update now-expired transactions that didn't get mined.
        stmt_update_expired.execute(&[last_height])?;
        // Commit the SQL transaction, writing this block's data atomically.
        data.execute("COMMIT", NO_PARAMS)?;
    }
    Ok(())
 }
 #[cfg(test)]
 mod tests {
    use tempfile::NamedTempFile;
    use zcash_primitives::{
        block::BlockHash,
        transaction::components::Amount,
        zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
    };
    use super::scan_cached_blocks;
    use crate::{
        init::{init_accounts_table, init_cache_database, init_data_database},
        query::get_balance,
        tests::{fake_compact_block, fake_compact_block_spending, insert_into_cache},
        SAPLING_ACTIVATION_HEIGHT,
    };
    #[test]
    fn scan_cached_blocks_requires_sequential_blocks() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Create a block with height SAPLING_ACTIVATION_HEIGHT
        let value = Amount::from_u64(50000).unwrap();
        let (cb1, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            value,
        );
        insert_into_cache(db_cache, &cb1);
        scan_cached_blocks(db_cache, db_data).unwrap();
        assert_eq!(get_balance(db_data, 0).unwrap(), value);
        // We cannot scan a block of height SAPLING_ACTIVATION_HEIGHT + 2 next
        let (cb2, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 1,
            cb1.hash(),
            extfvk.clone(),
            value,
        );
        let (cb3, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 2,
            cb2.hash(),
            extfvk.clone(),
            value,
        );
        insert_into_cache(db_cache, &cb3);
        match scan_cached_blocks(db_cache, db_data) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(
                e.to_string(),
                format!(
                    "Expected height of next CompactBlock to be {}, but was {}",
                    SAPLING_ACTIVATION_HEIGHT + 1,
                    SAPLING_ACTIVATION_HEIGHT + 2
                )
            ),
        }
        // If we add a block of height SAPLING_ACTIVATION_HEIGHT + 1, we can now scan both
        insert_into_cache(db_cache, &cb2);
        scan_cached_blocks(db_cache, db_data).unwrap();
        assert_eq!(
            get_balance(db_data, 0).unwrap(),
            Amount::from_u64(150_000).unwrap()
        );
    }
    #[test]
    fn scan_cached_blocks_finds_received_notes() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Account balance should be zero
        assert_eq!(get_balance(db_data, 0).unwrap(), Amount::zero());
        // Create a fake CompactBlock sending value to the address
        let value = Amount::from_u64(5).unwrap();
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            value,
        );
        insert_into_cache(db_cache, &cb);
        // Scan the cache
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Account balance should reflect the received note
        assert_eq!(get_balance(db_data, 0).unwrap(), value);
        // Create a second fake CompactBlock sending more value to the address
        let value2 = Amount::from_u64(7).unwrap();
        let (cb2, _) = fake_compact_block(SAPLING_ACTIVATION_HEIGHT + 1, cb.hash(), extfvk, value2);
        insert_into_cache(db_cache, &cb2);
        // Scan the cache again
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Account balance should reflect both received notes
        assert_eq!(get_balance(db_data, 0).unwrap(), value + value2);
    }
    #[test]
    fn scan_cached_blocks_finds_change_notes() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Account balance should be zero
        assert_eq!(get_balance(db_data, 0).unwrap(), Amount::zero());
        // Create a fake CompactBlock sending value to the address
        let value = Amount::from_u64(5).unwrap();
        let (cb, nf) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            value,
        );
        insert_into_cache(db_cache, &cb);
        // Scan the cache
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Account balance should reflect the received note
        assert_eq!(get_balance(db_data, 0).unwrap(), value);
        // Create a second fake CompactBlock spending value from the address
        let extsk2 = ExtendedSpendingKey::master(&[0]);
        let to2 = extsk2.default_address().unwrap().1;
        let value2 = Amount::from_u64(2).unwrap();
        insert_into_cache(
            db_cache,
            &fake_compact_block_spending(
                SAPLING_ACTIVATION_HEIGHT + 1,
                cb.hash(),
                (nf, value),
                extfvk,
                to2,
                value2,
            ),
        );
        // Scan the cache again
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Account balance should equal the change
        assert_eq!(get_balance(db_data, 0).unwrap(), value - value2);
    }
 }
--- a/zcash_client_sqlite/src/transact.rs
+++ b/zcash_client_sqlite/src/transact.rs
@@ -0,0 +1,665 @@
 //! Functions for creating transactions.
 use ff::{PrimeField, PrimeFieldRepr};
 use pairing::bls12_381::Bls12;
 use rusqlite::{types::ToSql, Connection, NO_PARAMS};
 use std::path::Path;
 use zcash_client_backend::encoding::encode_extended_full_viewing_key;
 use zcash_primitives::{
    jubjub::fs::{Fs, FsRepr},
    merkle_tree::IncrementalWitness,
    note_encryption::Memo,
    primitives::{Diversifier, Note},
    prover::TxProver,
    sapling::Node,
    transaction::{
        builder::Builder,
        components::{amount::DEFAULT_FEE, Amount},
    },
    zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
    JUBJUB,
 };
 use crate::{
    address::RecipientAddress,
    error::{Error, ErrorKind},
    get_target_and_anchor_heights, HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY,
 };
 struct SelectedNoteRow {
    diversifier: Diversifier,
    note: Note<Bls12>,
    witness: IncrementalWitness<Node>,
 }
 /// Creates a transaction paying the specified address from the given account.
 ///
 /// Returns the row index of the newly-created transaction in the `transactions` table
 /// within the data database. The caller can read the raw transaction bytes from the `raw`
 /// column in order to broadcast the transaction to the network.
 ///
 /// Do not call this multiple times in parallel, or you will generate transactions that
 /// double-spend the same notes.
 ///
 /// # Examples
 ///
 /// ```
 /// use zcash_client_backend::{
 ///     constants::{testnet::COIN_TYPE, SAPLING_CONSENSUS_BRANCH_ID},
 ///     keys::spending_key,
 /// };
 /// use zcash_client_sqlite::transact::create_to_address;
 /// use zcash_primitives::transaction::components::Amount;
 /// use zcash_proofs::prover::LocalTxProver;
 ///
 /// let tx_prover = match LocalTxProver::with_default_location() {
 ///     Some(tx_prover) => tx_prover,
 ///     None => {
 ///         panic!("Cannot locate the Zcash parameters. Please run zcash-fetch-params or fetch-params.sh to download the parameters, and then re-run the tests.");
 ///     }
 /// };
 ///
 /// let account = 0;
 /// let extsk = spending_key(&[0; 32][..], COIN_TYPE, account);
 /// let to = extsk.default_address().unwrap().1.into();
 /// match create_to_address(
 ///     "/path/to/data.db",
 ///     SAPLING_CONSENSUS_BRANCH_ID,
 ///     tx_prover,
 ///     (account, &extsk),
 ///     &to,
 ///     Amount::from_u64(1).unwrap(),
 ///     None,
 /// ) {
 ///     Ok(tx_row) => (),
 ///     Err(e) => (),
 /// }
 /// ```
 pub fn create_to_address<P: AsRef<Path>>(
    db_data: P,
    consensus_branch_id: u32,
    prover: impl TxProver,
    (account, extsk): (u32, &ExtendedSpendingKey),
    to: &RecipientAddress,
    value: Amount,
    memo: Option<Memo>,
 ) -> Result<i64, Error> {
    let data = Connection::open(db_data)?;
    // Check that the ExtendedSpendingKey we have been given corresponds to the
    // ExtendedFullViewingKey for the account we are spending from.
    let extfvk = ExtendedFullViewingKey::from(extsk);
    if !data
        .prepare("SELECT * FROM accounts WHERE account = ? AND extfvk = ?")?
        .exists(&[
            account.to_sql()?,
            encode_extended_full_viewing_key(HRP_SAPLING_EXTENDED_FULL_VIEWING_KEY, &extfvk)
                .to_sql()?,
        ])?
    {
        return Err(Error(ErrorKind::InvalidExtSK(account)));
    }
    let ovk = extfvk.fvk.ovk;
    // Target the next block, assuming we are up-to-date.
    let (height, anchor_height) = {
        let (target_height, anchor_height) = get_target_and_anchor_heights(&data)?;
        (target_height, i64::from(anchor_height))
    };
    // The goal of this SQL statement is to select the oldest notes until the required
    // value has been reached, and then fetch the witnesses at the desired height for the
    // selected notes. This is achieved in several steps:
    //
    // 1) Use a window function to create a view of all notes, ordered from oldest to
    //    newest, with an additional column containing a running sum:
    //    - Unspent notes accumulate the values of all unspent notes in that note's
    //      account, up to itself.
    //    - Spent notes accumulate the values of all notes in the transaction they were
    //      spent in, up to itself.
    //
    // 2) Select all unspent notes in the desired account, along with their running sum.
    //
    // 3) Select all notes for which the running sum was less than the required value, as
    //    well as a single note for which the sum was greater than or equal to the
    //    required value, bringing the sum of all selected notes across the threshold.
    //
    // 4) Match the selected notes against the witnesses at the desired height.
    let target_value = i64::from(value + DEFAULT_FEE);
    let mut stmt_select_notes = data.prepare(
        "WITH selected AS (
            WITH eligible AS (
                SELECT id_note, diversifier, value, rcm,
                    SUM(value) OVER
                        (PARTITION BY account, spent ORDER BY id_note) AS so_far
                FROM received_notes
                INNER JOIN transactions ON transactions.id_tx = received_notes.tx
                WHERE account = ? AND spent IS NULL AND transactions.block <= ?
            )
            SELECT * FROM eligible WHERE so_far < ?
            UNION
            SELECT * FROM (SELECT * FROM eligible WHERE so_far >= ? LIMIT 1)
        ), witnesses AS (
            SELECT note, witness FROM sapling_witnesses
            WHERE block = ?
        )
        SELECT selected.diversifier, selected.value, selected.rcm, witnesses.witness
        FROM selected
        INNER JOIN witnesses ON selected.id_note = witnesses.note",
    )?;
    // Select notes
    let notes = stmt_select_notes.query_and_then::<_, Error, _, _>(
        &[
            i64::from(account),
            anchor_height,
            target_value,
            target_value,
            anchor_height,
        ],
        |row| {
            let diversifier = {
                let d: Vec<_> = row.get(0)?;
                if d.len() != 11 {
                    return Err(Error(ErrorKind::CorruptedData(
                        "Invalid diversifier length",
                    )));
                }
                let mut tmp = [0; 11];
                tmp.copy_from_slice(&d);
                Diversifier(tmp)
            };
            let note_value: i64 = row.get(1)?;
            let rcm = {
                let d: Vec<_> = row.get(2)?;
                let mut tmp = FsRepr::default();
                tmp.read_le(&d[..])?;
                Fs::from_repr(tmp).map_err(|_| Error(ErrorKind::InvalidNote))?
            };
            let from = extfvk
                .fvk
                .vk
                .into_payment_address(diversifier, &JUBJUB)
                .unwrap();
            let note = from.create_note(note_value as u64, rcm, &JUBJUB).unwrap();
            let witness = {
                let d: Vec<_> = row.get(3)?;
                IncrementalWitness::read(&d[..])?
            };
            Ok(SelectedNoteRow {
                diversifier,
                note,
                witness,
            })
        },
    )?;
    let notes: Vec<SelectedNoteRow> = notes.collect::<Result<_, _>>()?;
    // Confirm we were able to select sufficient value
    let selected_value = notes
        .iter()
        .fold(0, |acc, selected| acc + selected.note.value);
    if selected_value < target_value as u64 {
        return Err(Error(ErrorKind::InsufficientBalance(
            selected_value,
            target_value as u64,
        )));
    }
    // Create the transaction
    let mut builder = Builder::new(height);
    for selected in notes {
        builder.add_sapling_spend(
            extsk.clone(),
            selected.diversifier,
            selected.note,
            selected.witness,
        )?;
    }
    match to {
        RecipientAddress::Shielded(to) => {
            builder.add_sapling_output(ovk, to.clone(), value, memo.clone())
        }
        RecipientAddress::Transparent(to) => builder.add_transparent_output(&to, value),
    }?;
    let (tx, tx_metadata) = builder.build(consensus_branch_id, prover)?;
    // We only called add_sapling_output() once.
    let output_index = match tx_metadata.output_index(0) {
        Some(idx) => idx as i64,
        None => panic!("Output 0 should exist in the transaction"),
    };
    let created = time::get_time();
    // Update the database atomically, to ensure the result is internally consistent.
    data.execute("BEGIN IMMEDIATE", NO_PARAMS)?;
    // Save the transaction in the database.
    let mut raw_tx = vec![];
    tx.write(&mut raw_tx)?;
    let mut stmt_insert_tx = data.prepare(
        "INSERT INTO transactions (txid, created, expiry_height, raw)
        VALUES (?, ?, ?, ?)",
    )?;
    stmt_insert_tx.execute(&[
        tx.txid().0.to_sql()?,
        created.to_sql()?,
        tx.expiry_height.to_sql()?,
        raw_tx.to_sql()?,
    ])?;
    let id_tx = data.last_insert_rowid();
    // Mark notes as spent.
    //
    // This locks the notes so they aren't selected again by a subsequent call to
    // create_to_address() before this transaction has been mined (at which point the notes
    // get re-marked as spent).
    //
    // Assumes that create_to_address() will never be called in parallel, which is a
    // reasonable assumption for a light client such as a mobile phone.
    let mut stmt_mark_spent_note =
        data.prepare("UPDATE received_notes SET spent = ? WHERE nf = ?")?;
    for spend in &tx.shielded_spends {
        stmt_mark_spent_note.execute(&[id_tx.to_sql()?, spend.nullifier.to_sql()?])?;
    }
    // Save the sent note in the database.
    // TODO: Decide how to save transparent output information.
    let to_str = to.to_string();
    if let Some(memo) = memo {
        let mut stmt_insert_sent_note = data.prepare(
            "INSERT INTO sent_notes (tx, output_index, from_account, address, value, memo)
            VALUES (?, ?, ?, ?, ?, ?)",
        )?;
        stmt_insert_sent_note.execute(&[
            id_tx.to_sql()?,
            output_index.to_sql()?,
            account.to_sql()?,
            to_str.to_sql()?,
            i64::from(value).to_sql()?,
            memo.as_bytes().to_sql()?,
        ])?;
    } else {
        let mut stmt_insert_sent_note = data.prepare(
            "INSERT INTO sent_notes (tx, output_index, from_account, address, value)
            VALUES (?, ?, ?, ?, ?)",
        )?;
        stmt_insert_sent_note.execute(&[
            id_tx.to_sql()?,
            output_index.to_sql()?,
            account.to_sql()?,
            to_str.to_sql()?,
            i64::from(value).to_sql()?,
        ])?;
    }
    data.execute("COMMIT", NO_PARAMS)?;
    // Return the row number of the transaction, so the caller can fetch it for sending.
    Ok(id_tx)
 }
 #[cfg(test)]
 mod tests {
    use tempfile::NamedTempFile;
    use zcash_primitives::{
        block::BlockHash,
        prover::TxProver,
        transaction::components::Amount,
        zip32::{ExtendedFullViewingKey, ExtendedSpendingKey},
    };
    use zcash_proofs::prover::LocalTxProver;
    use super::create_to_address;
    use crate::{
        init::{init_accounts_table, init_blocks_table, init_cache_database, init_data_database},
        query::{get_balance, get_verified_balance},
        scan::scan_cached_blocks,
        tests::{fake_compact_block, insert_into_cache},
        SAPLING_ACTIVATION_HEIGHT,
    };
    fn test_prover() -> impl TxProver {
        match LocalTxProver::with_default_location() {
            Some(tx_prover) => tx_prover,
            None => {
                panic!("Cannot locate the Zcash parameters. Please run zcash-fetch-params or fetch-params.sh to download the parameters, and then re-run the tests.");
            }
        }
    }
    #[test]
    fn create_to_address_fails_on_incorrect_extsk() {
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add two accounts to the wallet
        let extsk0 = ExtendedSpendingKey::master(&[]);
        let extsk1 = ExtendedSpendingKey::master(&[0]);
        let extfvks = [
            ExtendedFullViewingKey::from(&extsk0),
            ExtendedFullViewingKey::from(&extsk1),
        ];
        init_accounts_table(&db_data, &extfvks).unwrap();
        let to = extsk0.default_address().unwrap().1.into();
        // Invalid extsk for the given account should cause an error
        match create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk1),
            &to,
            Amount::from_u64(1).unwrap(),
            None,
        ) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(e.to_string(), "Incorrect ExtendedSpendingKey for account 0"),
        }
        match create_to_address(
            db_data,
            1,
            test_prover(),
            (1, &extsk0),
            &to,
            Amount::from_u64(1).unwrap(),
            None,
        ) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(e.to_string(), "Incorrect ExtendedSpendingKey for account 1"),
        }
    }
    #[test]
    fn create_to_address_fails_with_no_blocks() {
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvks = [ExtendedFullViewingKey::from(&extsk)];
        init_accounts_table(&db_data, &extfvks).unwrap();
        let to = extsk.default_address().unwrap().1.into();
        // We cannot do anything if we aren't synchronised
        match create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(1).unwrap(),
            None,
        ) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(e.to_string(), "Must scan blocks first"),
        }
    }
    #[test]
    fn create_to_address_fails_on_insufficient_balance() {
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        init_blocks_table(&db_data, 1, BlockHash([1; 32]), 1, &[]).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvks = [ExtendedFullViewingKey::from(&extsk)];
        init_accounts_table(&db_data, &extfvks).unwrap();
        let to = extsk.default_address().unwrap().1.into();
        // Account balance should be zero
        assert_eq!(get_balance(db_data, 0).unwrap(), Amount::zero());
        // We cannot spend anything
        match create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(1).unwrap(),
            None,
        ) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(
                e.to_string(),
                "Insufficient balance (have 0, need 10001 including fee)"
            ),
        }
    }
    #[test]
    fn create_to_address_fails_on_unverified_notes() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Add funds to the wallet in a single note
        let value = Amount::from_u64(50000).unwrap();
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            value,
        );
        insert_into_cache(db_cache, &cb);
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Verified balance matches total balance
        assert_eq!(get_balance(db_data, 0).unwrap(), value);
        assert_eq!(get_verified_balance(db_data, 0).unwrap(), value);
        // Add more funds to the wallet in a second note
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 1,
            cb.hash(),
            extfvk.clone(),
            value,
        );
        insert_into_cache(db_cache, &cb);
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Verified balance does not include the second note
        assert_eq!(get_balance(db_data, 0).unwrap(), value + value);
        assert_eq!(get_verified_balance(db_data, 0).unwrap(), value);
        // Spend fails because there are insufficient verified notes
        let extsk2 = ExtendedSpendingKey::master(&[]);
        let to = extsk2.default_address().unwrap().1.into();
        match create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(70000).unwrap(),
            None,
        ) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(
                e.to_string(),
                "Insufficient balance (have 50000, need 80000 including fee)"
            ),
        }
        // Mine blocks SAPLING_ACTIVATION_HEIGHT + 2 to 9 until just before the second
        // note is verified
        for i in 2..10 {
            let (cb, _) = fake_compact_block(
                SAPLING_ACTIVATION_HEIGHT + i,
                cb.hash(),
                extfvk.clone(),
                value,
            );
            insert_into_cache(db_cache, &cb);
        }
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Second spend still fails
        match create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(70000).unwrap(),
            None,
        ) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(
                e.to_string(),
                "Insufficient balance (have 50000, need 80000 including fee)"
            ),
        }
        // Mine block 11 so that the second note becomes verified
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 10,
            cb.hash(),
            extfvk.clone(),
            value,
        );
        insert_into_cache(db_cache, &cb);
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Second spend should now succeed
        create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(70000).unwrap(),
            None,
        )
        .unwrap();
    }
    #[test]
    fn create_to_address_fails_on_locked_notes() {
        let cache_file = NamedTempFile::new().unwrap();
        let db_cache = cache_file.path();
        init_cache_database(&db_cache).unwrap();
        let data_file = NamedTempFile::new().unwrap();
        let db_data = data_file.path();
        init_data_database(&db_data).unwrap();
        // Add an account to the wallet
        let extsk = ExtendedSpendingKey::master(&[]);
        let extfvk = ExtendedFullViewingKey::from(&extsk);
        init_accounts_table(&db_data, &[extfvk.clone()]).unwrap();
        // Add funds to the wallet in a single note
        let value = Amount::from_u64(50000).unwrap();
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT,
            BlockHash([0; 32]),
            extfvk.clone(),
            value,
        );
        insert_into_cache(db_cache, &cb);
        scan_cached_blocks(db_cache, db_data).unwrap();
        assert_eq!(get_balance(db_data, 0).unwrap(), value);
        // Send some of the funds to another address
        let extsk2 = ExtendedSpendingKey::master(&[]);
        let to = extsk2.default_address().unwrap().1.into();
        create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(15000).unwrap(),
            None,
        )
        .unwrap();
        // A second spend fails because there are no usable notes
        match create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(2000).unwrap(),
            None,
        ) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(
                e.to_string(),
                "Insufficient balance (have 0, need 12000 including fee)"
            ),
        }
        // Mine blocks SAPLING_ACTIVATION_HEIGHT + 1 to 21 (that don't send us funds)
        // until just before the first transaction expires
        for i in 1..22 {
            let (cb, _) = fake_compact_block(
                SAPLING_ACTIVATION_HEIGHT + i,
                cb.hash(),
                ExtendedFullViewingKey::from(&ExtendedSpendingKey::master(&[i as u8])),
                value,
            );
            insert_into_cache(db_cache, &cb);
        }
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Second spend still fails
        match create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(2000).unwrap(),
            None,
        ) {
            Ok(_) => panic!("Should have failed"),
            Err(e) => assert_eq!(
                e.to_string(),
                "Insufficient balance (have 0, need 12000 including fee)"
            ),
        }
        // Mine block SAPLING_ACTIVATION_HEIGHT + 22 so that the first transaction expires
        let (cb, _) = fake_compact_block(
            SAPLING_ACTIVATION_HEIGHT + 22,
            cb.hash(),
            ExtendedFullViewingKey::from(&ExtendedSpendingKey::master(&[22])),
            value,
        );
        insert_into_cache(db_cache, &cb);
        scan_cached_blocks(db_cache, db_data).unwrap();
        // Second spend should now succeed
        create_to_address(
            db_data,
            1,
            test_prover(),
            (0, &extsk),
            &to,
            Amount::from_u64(2000).unwrap(),
            None,
        )
        .unwrap();
    }
 }
--- a/zcash_primitives/Cargo.toml
+++ b/zcash_primitives/Cargo.toml
@@ -19,8 +19,13 @@ pairing = { path = "../pairing" }
 rand = "0.7"
 rand_core = "0.5"
 rand_os = "0.2"
 ripemd160 = { version = "0.8", optional = true }
 secp256k1 = { version = "=0.15.0", optional = true }
 sha2 = "0.8"
 [dev-dependencies]
 hex-literal = "0.1"
 rand_xorshift = "0.2"
 [features]
 transparent-inputs = ["ripemd160", "secp256k1"]
--- a/zcash_primitives/src/block.rs
+++ b/zcash_primitives/src/block.rs
@@ -1,5 +1,6 @@
 use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
 use hex;
 use sha2::{Digest, Sha256};
 use std::fmt;
 use std::io::{self, Read, Write};
 use std::ops::Deref;
@@ -17,14 +18,31 @@ impl fmt::Display for BlockHash {
    }
 }
 impl BlockHash {
    /// Constructs a [`BlockHash`] from the given slice.
    ///
    /// # Panics
    ///
    /// This function will panic if the slice is not exactly 32 bytes.
    pub fn from_slice(bytes: &[u8]) -> Self {
        assert_eq!(bytes.len(), 32);
        let mut hash = [0; 32];
        hash.copy_from_slice(&bytes);
        BlockHash(hash)
    }
 }
 /// A Zcash block header.
-pub struct BlockHeader(BlockHeaderData);
+pub struct BlockHeader {
    hash: BlockHash,
    data: BlockHeaderData,
 }
 impl Deref for BlockHeader {
    type Target = BlockHeaderData;
    fn deref(&self) -> &BlockHeaderData {
-        &self.0
+        &self.data
    }
 }
@@ -40,12 +58,31 @@ pub struct BlockHeaderData {
 }
 impl BlockHeaderData {
-    pub fn freeze(self) -> BlockHeader {
+    pub fn freeze(self) -> io::Result<BlockHeader> {
-        BlockHeader(self)
+        BlockHeader::from_data(self)
    }
 }
 impl BlockHeader {
    fn from_data(data: BlockHeaderData) -> io::Result<Self> {
        let mut header = BlockHeader {
            hash: BlockHash([0; 32]),
            data,
        };
        let mut raw = vec![];
        header.write(&mut raw)?;
        header
            .hash
            .0
            .copy_from_slice(&Sha256::digest(&Sha256::digest(&raw)));
        Ok(header)
    }
    /// Returns the hash of this header.
    pub fn hash(&self) -> BlockHash {
        self.hash
    }
    pub fn read<R: Read>(mut reader: R) -> io::Result<Self> {
        let version = reader.read_i32::<LittleEndian>()?;
@@ -66,7 +103,7 @@ impl BlockHeader {
        let solution = Vector::read(&mut reader, |r| r.read_u8())?;
-        Ok(BlockHeader(BlockHeaderData {
+        BlockHeader::from_data(BlockHeaderData {
            version,
            prev_block,
            merkle_root,
@@ -75,7 +112,7 @@ impl BlockHeader {
            bits,
            nonce,
            solution,
-        }))
+        })
    }
    pub fn write<W: Write>(&self, mut writer: W) -> io::Result<()> {
@@ -202,6 +239,10 @@ mod tests {
    #[test]
    fn header_read_write() {
        let header = BlockHeader::read(&HEADER_MAINNET_415000[..]).unwrap();
        assert_eq!(
            format!("{}", header.hash()),
            "0000000001ab37793ce771262b2ffa082519aa3fe891250a1adb43baaf856168"
        );
        let mut encoded = Vec::with_capacity(HEADER_MAINNET_415000.len());
        header.write(&mut encoded).unwrap();
        assert_eq!(&HEADER_MAINNET_415000[..], &encoded[..]);
--- a/zcash_primitives/src/legacy.rs
+++ b/zcash_primitives/src/legacy.rs
@@ -26,7 +26,7 @@ enum OpCode {
 }
 /// A serialized script, used inside transparent inputs and outputs of a transaction.
-#[derive(Debug, Default)]
+#[derive(Clone, Debug, Default)]
 pub struct Script(pub Vec<u8>);
 impl Script {
@@ -38,6 +38,31 @@ impl Script {
    pub fn write<W: Write>(&self, mut writer: W) -> io::Result<()> {
        Vector::write(&mut writer, &self.0, |w, e| w.write_u8(*e))
    }
    /// Returns the address that this Script contains, if any.
    pub fn address(&self) -> Option<TransparentAddress> {
        if self.0.len() == 25
            && self.0[0] == OpCode::Dup as u8
            && self.0[1] == OpCode::Hash160 as u8
            && self.0[2] == 0x14
            && self.0[23] == OpCode::EqualVerify as u8
            && self.0[24] == OpCode::CheckSig as u8
        {
            let mut hash = [0; 20];
            hash.copy_from_slice(&self.0[3..23]);
            Some(TransparentAddress::PublicKey(hash))
        } else if self.0.len() == 23
            && self.0[0] == OpCode::Hash160 as u8
            && self.0[1] == 0x14
            && self.0[22] == OpCode::Equal as u8
        {
            let mut hash = [0; 20];
            hash.copy_from_slice(&self.0[2..22]);
            Some(TransparentAddress::Script(hash))
        } else {
            None
        }
    }
 }
 impl Shl<OpCode> for Script {
@@ -144,25 +169,27 @@ mod tests {
    #[test]
    fn p2pkh() {
-        let addr = TransparentAddress::PublicKey([4; 20]);
+        let addr = TransparentAddress::PublicKey([4; 21]);
        assert_eq!(
            &addr.script().0,
            &[
                0x76, 0xa9, 0x14, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04,
                0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x88, 0xac,
            ]
-        )
+        );
        assert_eq!(addr.script().address(), Some(addr));
    }
    #[test]
    fn p2sh() {
-        let addr = TransparentAddress::Script([7; 20]);
+        let addr = TransparentAddress::Script([7; 21]);
        assert_eq!(
            &addr.script().0,
            &[
                0xa9, 0x14, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07,
                0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x07, 0x87,
            ]
-        )
+        );
        assert_eq!(addr.script().address(), Some(addr));
    }
 }
--- a/zcash_primitives/src/lib.rs
+++ b/zcash_primitives/src/lib.rs
@@ -15,6 +15,12 @@ extern crate rand_core;
 extern crate rand_os;
 extern crate sha2;
 #[cfg(feature = "transparent-inputs")]
 extern crate ripemd160;
 #[cfg(feature = "transparent-inputs")]
 extern crate secp256k1;
 #[cfg(test)]
 #[macro_use]
 extern crate hex_literal;
@@ -35,7 +41,7 @@ pub mod primitives;
 pub mod prover;
 pub mod redjubjub;
 pub mod sapling;
-mod serialize;
+pub mod serialize;
 pub mod transaction;
 mod util;
 pub mod zip32;
--- a/zcash_primitives/src/serialize.rs
+++ b/zcash_primitives/src/serialize.rs
@@ -1,7 +1,7 @@
 use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
 use std::io::{self, Read, Write};
-const MAX_SIZE: usize = 0x02000000;
+const MAX_SIZE: usize = 0x02100000;
 struct CompactSize;
--- a/zcash_primitives/src/transaction/builder.rs
+++ b/zcash_primitives/src/transaction/builder.rs
@@ -7,6 +7,8 @@ use crate::{
 use ff::Field;
 use pairing::bls12_381::{Bls12, Fr};
 use rand::{rngs::OsRng, seq::SliceRandom, CryptoRng, RngCore};
 use std::error;
 use std::fmt;
 use zip32::ExtendedSpendingKey;
 use crate::{
@@ -24,6 +26,12 @@ use crate::{
    JUBJUB,
 };
 #[cfg(feature = "transparent-inputs")]
 use crate::{
    legacy::Script,
    transaction::components::{OutPoint, TxIn},
 };
 const DEFAULT_TX_EXPIRY_DELTA: u32 = 20;
 /// If there are any shielded inputs, always have at least two shielded outputs, padding
@@ -42,6 +50,27 @@ pub enum Error {
    SpendProof,
 }
 impl fmt::Display for Error {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        match self {
            Error::AnchorMismatch => {
                write!(f, "Anchor mismatch (anchors for all spends must be equal)")
            }
            Error::BindingSig => write!(f, "Failed to create bindingSig"),
            Error::ChangeIsNegative(amount) => {
                write!(f, "Change is negative ({:?} zatoshis)", amount)
            }
            Error::InvalidAddress => write!(f, "Invalid address"),
            Error::InvalidAmount => write!(f, "Invalid amount"),
            Error::InvalidWitness => write!(f, "Invalid note witness"),
            Error::NoChangeAddress => write!(f, "No change address specified or discoverable"),
            Error::SpendProof => write!(f, "Failed to create Sapling spend proof"),
        }
    }
 }
 impl error::Error for Error {}
 struct SpendDescriptionInfo {
    extsk: ExtendedSpendingKey,
    diversifier: Diversifier,
@@ -130,6 +159,50 @@ impl SaplingOutput {
    }
 }
 #[cfg(feature = "transparent-inputs")]
 struct TransparentInputInfo {
    sk: secp256k1::SecretKey,
    pubkey: [u8; secp256k1::constants::PUBLIC_KEY_SIZE],
    coin: TxOut,
 }
 #[cfg(feature = "transparent-inputs")]
 struct TransparentInputs {
    secp: secp256k1::Secp256k1<secp256k1::SignOnly>,
    inputs: Vec<TransparentInputInfo>,
 }
 #[cfg(feature = "transparent-inputs")]
 impl Default for TransparentInputs {
    fn default() -> Self {
        TransparentInputs {
            secp: secp256k1::Secp256k1::gen_new(),
            inputs: Default::default(),
        }
    }
 }
 #[cfg(not(feature = "transparent-inputs"))]
 #[derive(Default)]
 struct TransparentInputs;
 impl TransparentInputs {
    fn input_sum(&self) -> Amount {
        #[cfg(feature = "transparent-inputs")]
        {
            self.inputs
                .iter()
                .map(|input| input.coin.value)
                .sum::<Amount>()
        }
        #[cfg(not(feature = "transparent-inputs"))]
        {
            Amount::zero()
        }
    }
 }
 /// Metadata about a transaction created by a [`Builder`].
 #[derive(Debug, PartialEq)]
 pub struct TransactionMetadata {
@@ -176,6 +249,7 @@ pub struct Builder<R: RngCore + CryptoRng> {
    anchor: Option<Fr>,
    spends: Vec<SpendDescriptionInfo>,
    outputs: Vec<SaplingOutput>,
    legacy: TransparentInputs,
    change_address: Option<(OutgoingViewingKey, PaymentAddress<Bls12>)>,
 }
@@ -215,10 +289,15 @@ impl<R: RngCore + CryptoRng> Builder<R> {
            anchor: None,
            spends: vec![],
            outputs: vec![],
            legacy: TransparentInputs::default(),
            change_address: None,
        }
    }
    pub fn set_fee(&mut self, fee: Amount) {
        self.fee = fee;
    }
    /// Adds a Sapling note to be spent in this transaction.
    ///
    /// Returns an error if the given witness does not have the same anchor as previous
@@ -273,6 +352,39 @@ impl<R: RngCore + CryptoRng> Builder<R> {
        Ok(())
    }
    /// Adds a transparent coin to be spent in this transaction.
    #[cfg(feature = "transparent-inputs")]
    pub fn add_transparent_input(
        &mut self,
        sk: secp256k1::SecretKey,
        utxo: OutPoint,
        coin: TxOut,
    ) -> Result<(), Error> {
        if coin.value.is_negative() {
            return Err(Error::InvalidAmount);
        }
        let pubkey = secp256k1::PublicKey::from_secret_key(&self.legacy.secp, &sk).serialize();
        match coin.script_pubkey.address() {
            Some(TransparentAddress::PublicKey(hash)) => {
                use ripemd160::Ripemd160;
                use sha2::{Digest, Sha256};
                if &hash[..] != &Ripemd160::digest(&Sha256::digest(&pubkey))[..] {
                    return Err(Error::InvalidAddress);
                }
            }
            _ => return Err(Error::InvalidAddress),
        }
        self.mtx.vin.push(TxIn::new(utxo));
        self.legacy
            .inputs
            .push(TransparentInputInfo { sk, pubkey, coin });
        Ok(())
    }
    /// Adds a transparent address to send funds to.
    pub fn add_transparent_output(
        &mut self,
@@ -320,8 +432,7 @@ impl<R: RngCore + CryptoRng> Builder<R> {
        //
        // Valid change
-        let change = self.mtx.value_balance
+        let change = self.mtx.value_balance - self.fee + self.legacy.input_sum()
            - self.fee
            - self
                .mtx
                .vout
@@ -372,7 +483,6 @@ impl<R: RngCore + CryptoRng> Builder<R> {
        //
        let mut ctx = prover.new_sapling_proving_context();
        let anchor = self.anchor.expect("anchor was set if spends were added");
        // Pad Sapling outputs
        let orig_outputs_len = outputs.len();
@@ -389,40 +499,44 @@ impl<R: RngCore + CryptoRng> Builder<R> {
        tx_metadata.output_indices.resize(orig_outputs_len, 0);
        // Create Sapling SpendDescriptions
-        for (i, (pos, spend)) in spends.iter().enumerate() {
+        if spends.len() > 0 {
-            let proof_generation_key = spend.extsk.expsk.proof_generation_key(&JUBJUB);
+            let anchor = self.anchor.expect("anchor was set if spends were added");
-            let mut nullifier = [0u8; 32];
+            for (i, (pos, spend)) in spends.iter().enumerate() {
-            nullifier.copy_from_slice(&spend.note.nf(
+                let proof_generation_key = spend.extsk.expsk.proof_generation_key(&JUBJUB);
                &proof_generation_key.into_viewing_key(&JUBJUB),
                spend.witness.position,
                &JUBJUB,
            ));
-            let (zkproof, cv, rk) = prover
+                let mut nullifier = [0u8; 32];
-                .spend_proof(
+                nullifier.copy_from_slice(&spend.note.nf(
-                    &mut ctx,
+                    &proof_generation_key.into_viewing_key(&JUBJUB),
-                    proof_generation_key,
+                    spend.witness.position,
-                    spend.diversifier,
+                    &JUBJUB,
-                    spend.note.r,
+                ));
                    spend.alpha,
                    spend.note.value,
                    anchor,
                    spend.witness.clone(),
                )
                .map_err(|()| Error::SpendProof)?;
-            self.mtx.shielded_spends.push(SpendDescription {
+                let (zkproof, cv, rk) = prover
-                cv,
+                    .spend_proof(
-                anchor: anchor,
+                        &mut ctx,
-                nullifier,
+                        proof_generation_key,
-                rk,
+                        spend.diversifier,
-                zkproof,
+                        spend.note.r,
-                spend_auth_sig: None,
+                        spend.alpha,
-            });
+                        spend.note.value,
                        anchor,
                        spend.witness.clone(),
                    )
                    .map_err(|()| Error::SpendProof)?;
-            // Record the post-randomized spend location
+                self.mtx.shielded_spends.push(SpendDescription {
-            tx_metadata.spend_indices[*pos] = i;
+                    cv,
                    anchor: anchor,
                    nullifier,
                    rk,
                    zkproof,
                    spend_auth_sig: None,
                });
                // Record the post-randomized spend location
                tx_metadata.spend_indices[*pos] = i;
            }
        }
        // Create Sapling OutputDescriptions
@@ -523,6 +637,30 @@ impl<R: RngCore + CryptoRng> Builder<R> {
                .map_err(|()| Error::BindingSig)?,
        );
        // Transparent signatures
        #[cfg(feature = "transparent-inputs")]
        {
            for (i, info) in self.legacy.inputs.iter().enumerate() {
                sighash.copy_from_slice(&signature_hash_data(
                    &self.mtx,
                    consensus_branch_id,
                    SIGHASH_ALL,
                    Some((i, &info.coin.script_pubkey, info.coin.value)),
                ));
                let msg = secp256k1::Message::from_slice(&sighash).expect("32 bytes");
                let sig = self.legacy.secp.sign(&msg, &info.sk);
                // Signature has to have "SIGHASH_ALL" appended to it
                let mut sig_bytes: Vec<u8> = sig.serialize_der()[..].to_vec();
                sig_bytes.extend(&[SIGHASH_ALL as u8]);
                // P2PKH scriptSig
                self.mtx.vin[i].script_sig =
                    Script::default() << &sig_bytes[..] << &info.pubkey[..];
            }
        }
        Ok((
            self.mtx.freeze().expect("Transaction should be complete"),
            tx_metadata,
--- a/zcash_primitives/src/transaction/components.rs
+++ b/zcash_primitives/src/transaction/components.rs
@@ -19,13 +19,17 @@ const PHGR_PROOF_SIZE: usize = (33 + 33 + 65 + 33 + 33 + 33 + 33 + 33);
 const ZC_NUM_JS_INPUTS: usize = 2;
 const ZC_NUM_JS_OUTPUTS: usize = 2;
-#[derive(Debug)]
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub struct OutPoint {
-    hash: [u8; 32],
+    pub hash: [u8; 32],
-    n: u32,
+    pub n: u32,
 }
 impl OutPoint {
    pub fn new(hash: [u8; 32], n: u32) -> Self {
        OutPoint {hash, n}
    }
    pub fn read<R: Read>(mut reader: R) -> io::Result<Self> {
        let mut hash = [0; 32];
        reader.read_exact(&mut hash)?;
@@ -42,11 +46,20 @@ impl OutPoint {
 #[derive(Debug)]
 pub struct TxIn {
    pub prevout: OutPoint,
-    script_sig: Script,
+    pub script_sig: Script,
    pub sequence: u32,
 }
 impl TxIn {
    #[cfg(feature = "transparent-inputs")]
    pub fn new(prevout: OutPoint) -> Self {
        TxIn {
            prevout,
            script_sig: Script::default(),
            sequence: std::u32::MAX,
        }
    }
    pub fn read<R: Read>(mut reader: &mut R) -> io::Result<Self> {
        let prevout = OutPoint::read(&mut reader)?;
        let script_sig = Script::read(&mut reader)?;
@@ -66,7 +79,7 @@ impl TxIn {
    }
 }
-#[derive(Debug)]
+#[derive(Clone, Debug)]
 pub struct TxOut {
    pub value: Amount,
    pub script_pubkey: Script,
--- a/zcash_primitives/src/transaction/mod.rs
+++ b/zcash_primitives/src/transaction/mod.rs
@@ -24,7 +24,7 @@ const OVERWINTER_TX_VERSION: u32 = 3;
 const SAPLING_VERSION_GROUP_ID: u32 = 0x892F2085;
 const SAPLING_TX_VERSION: u32 = 4;
-#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+#[derive(Clone, Copy, Debug, PartialOrd, Ord, PartialEq, Eq, Hash)]
 pub struct TxId(pub [u8; 32]);
 impl fmt::Display for TxId {
@@ -38,8 +38,8 @@ impl fmt::Display for TxId {
 /// A Zcash transaction.
 #[derive(Debug)]
 pub struct Transaction {
-    txid: TxId,
+    pub txid: TxId,
-    data: TransactionData,
+    pub data: TransactionData,
 }
 impl Deref for Transaction {
--- a/zcash_primitives/src/transaction/sighash.rs
+++ b/zcash_primitives/src/transaction/sighash.rs
@@ -154,7 +154,7 @@ pub fn signature_hash_data(
    tx: &TransactionData,
    consensus_branch_id: u32,
    hash_type: u32,
-    transparent_input: Option<(usize, Script, Amount)>,
+    transparent_input: Option<(usize, &Script, Amount)>,
 ) -> Vec<u8> {
    let sigversion = SigHashVersion::from_tx(tx);
    match sigversion {
@@ -232,7 +232,7 @@ pub fn signature_hash(
    tx: &Transaction,
    consensus_branch_id: u32,
    hash_type: u32,
-    transparent_input: Option<(usize, Script, Amount)>,
+    transparent_input: Option<(usize, &Script, Amount)>,
 ) -> Vec<u8> {
    signature_hash_data(tx, consensus_branch_id, hash_type, transparent_input)
 }
--- a/zcash_primitives/src/transaction/tests.rs
+++ b/zcash_primitives/src/transaction/tests.rs
@@ -212,7 +212,7 @@ fn tx_write_rejects_unexpected_binding_sig() {
 fn zip_0143() {
    struct TestVector {
        tx: Vec<u8>,
-        script_code: Vec<u8>,
+        script_code: Script,
        transparent_input: Option<u32>,
        hash_type: u32,
        amount: i64,
@@ -229,7 +229,7 @@ fn zip_0143() {
                0xb2, 0x83, 0x5a, 0x08, 0x05, 0x75, 0x02, 0x00, 0x02, 0x51, 0x51, 0x48, 0x1c, 0xdd,
                0x86, 0xb3, 0xcc, 0x43, 0x18, 0x00,
            ],
-            script_code: vec![0x6a, 0x00, 0x00, 0x00, 0x63, 0xac, 0x53],
+            script_code: Script(vec![0x6a, 0x00, 0x00, 0x00, 0x63, 0xac, 0x53]),
            transparent_input: None,
            hash_type: 1,
            amount: 1672704339313879,
@@ -518,7 +518,7 @@ fn zip_0143() {
                0xb1, 0xfa, 0x45, 0xad, 0x61, 0xce, 0x9a, 0x1c, 0x47, 0x27, 0xb7, 0xaa, 0xa5, 0x35,
                0x62, 0xf5, 0x23, 0xe7, 0x39, 0x52,
            ],
-            script_code: vec![0x53],
+            script_code: Script(vec![0x53]),
            transparent_input: Some(1),
            hash_type: 3,
            amount: 365293780364847,
@@ -678,7 +678,7 @@ fn zip_0143() {
                0x62, 0x91, 0x85, 0x00, 0x2c, 0x72, 0xc0, 0x12, 0xc4, 0x14, 0xd2, 0x38, 0x2a, 0x6d,
                0x47, 0xc7, 0xb3, 0xde, 0xab, 0xa7,
            ],
-            script_code: vec![0xac, 0x00],
+            script_code: Script(vec![0xac, 0x00]),
            transparent_input: Some(0),
            hash_type: 3,
            amount: 711752082734717,
@@ -960,7 +960,7 @@ fn zip_0143() {
                0xce, 0x1f, 0xca, 0x2c, 0x63, 0xfe, 0x06, 0xb7, 0x98, 0x9d, 0x58, 0x4f, 0xa7, 0xd7,
                0x82, 0xa8, 0x8c, 0x1e, 0x7d, 0x64, 0xb6, 0xfb, 0xf5, 0x5e, 0x35,
            ],
-            script_code: vec![0x6a, 0x53, 0x53, 0x63],
+            script_code: Script(vec![0x6a, 0x53, 0x53, 0x63]),
            transparent_input: None,
            hash_type: 1,
            amount: 379068098637835,
@@ -1119,7 +1119,7 @@ fn zip_0143() {
                0xc1, 0xc4, 0xf2, 0xca, 0xcd, 0xa3, 0x0b, 0xdb, 0x69, 0x30, 0x65, 0x3c, 0x0c, 0xc4,
                0x48, 0x6e, 0x60, 0xe8, 0x9f, 0xa8, 0x49, 0xb3,
            ],
-            script_code: vec![0x53, 0x52],
+            script_code: Script(vec![0x53, 0x52]),
            transparent_input: Some(0),
            hash_type: 3,
            amount: 1437866676382615,
@@ -1139,7 +1139,7 @@ fn zip_0143() {
                0x08, 0xf0, 0x83, 0x05, 0x00, 0x09, 0x63, 0x6a, 0x52, 0x63, 0x51, 0x63, 0x00, 0x6a,
                0xac, 0x9a, 0xbc, 0xef, 0x2a, 0x99, 0x08, 0x73, 0x19, 0x00,
            ],
-            script_code: vec![0x63],
+            script_code: Script(vec![0x63]),
            transparent_input: None,
            hash_type: 1,
            amount: 1993227025071196,
@@ -1162,7 +1162,7 @@ fn zip_0143() {
                0x87, 0x01, 0xff, 0x01, 0x86, 0xd2, 0x6f, 0xee, 0x28, 0xca, 0x06, 0x00, 0x01, 0xac,
                0x5a, 0xa7, 0x27, 0xab, 0x79, 0x85, 0xda, 0x0e, 0x00,
            ],
-            script_code: vec![0x65, 0x53, 0x51],
+            script_code: Script(vec![0x65, 0x53, 0x51]),
            transparent_input: Some(1),
            hash_type: 130,
            amount: 449567650863240,
@@ -1444,7 +1444,7 @@ fn zip_0143() {
                0xba, 0xfe, 0xc8, 0x84, 0x0c, 0x2d, 0x25, 0x5b, 0xf5, 0xad, 0x61, 0xc4, 0x60, 0xf9,
                0x8f, 0xeb, 0x82, 0xa1, 0x0f, 0xa1, 0xc0,
            ],
-            script_code: vec![0x65, 0x6a, 0x65, 0x51, 0x52, 0x65, 0x63],
+            script_code: Script(vec![0x65, 0x6a, 0x65, 0x51, 0x52, 0x65, 0x63]),
            transparent_input: None,
            hash_type: 1,
            amount: 1712463999734827,
@@ -1602,7 +1602,7 @@ fn zip_0143() {
                0xd9, 0xa9, 0xd9, 0xf5, 0x4f, 0xb2, 0xfe, 0x8f, 0x9f, 0x05, 0xcd, 0x11, 0x1e, 0xe4,
                0x6c, 0x47, 0x10, 0xf6, 0xf6, 0x3a, 0x62, 0x69, 0x45, 0x57,
            ],
-            script_code: vec![0x53, 0x52, 0x00],
+            script_code: Script(vec![0x53, 0x52, 0x00]),
            transparent_input: Some(1),
            hash_type: 1,
            amount: 1564816348934332,
@@ -1885,7 +1885,7 @@ fn zip_0143() {
                0x54, 0xa7, 0x89, 0x73, 0x5b, 0x03, 0x49, 0xc4, 0xd5, 0x1c, 0x88, 0x9d, 0x08, 0x95,
                0x2d, 0xdd, 0x54, 0x88, 0xbe, 0x95, 0x56, 0x05, 0x94, 0xe6,
            ],
-            script_code: vec![0x52, 0x63, 0x53, 0x51, 0x65],
+            script_code: Script(vec![0x52, 0x63, 0x53, 0x51, 0x65]),
            transparent_input: Some(0),
            hash_type: 2,
            amount: 483959951916902,
@@ -1903,7 +1903,7 @@ fn zip_0143() {
        let transparent_input = if let Some(n) = tv.transparent_input {
            Some((
                n as usize,
-                Script(tv.script_code),
+                &tv.script_code,
                Amount::from_nonnegative_i64(tv.amount).unwrap(),
            ))
        } else {
@@ -1921,7 +1921,7 @@ fn zip_0143() {
 fn zip_0243() {
    struct TestVector {
        tx: Vec<u8>,
-        script_code: Vec<u8>,
+        script_code: Script,
        transparent_input: Option<u32>,
        hash_type: u32,
        amount: i64,
@@ -2229,7 +2229,7 @@ fn zip_0243() {
                0xe4, 0x62, 0xef, 0xf9, 0xba, 0x8b, 0x3f, 0x4b, 0xfa, 0xa1, 0x30, 0x0c, 0x26, 0x92,
                0x5a, 0x87,
            ],
-            script_code: vec![0x63],
+            script_code: Script(vec![0x63]),
            transparent_input: None,
            hash_type: 1,
            amount: 1969273897303781,
@@ -2462,7 +2462,7 @@ fn zip_0243() {
                0xed, 0x6a, 0x9f, 0x08, 0x46, 0x4d, 0x56, 0x55, 0x93, 0xe1, 0xa6, 0x3b, 0x93, 0x85,
                0x36, 0xb4, 0x92, 0x44, 0xe9, 0x7d,
            ],
-            script_code: vec![],
+            script_code: Script(vec![]),
            transparent_input: Some(1),
            hash_type: 2,
            amount: 652655344020909,
@@ -3048,7 +3048,7 @@ fn zip_0243() {
                0x76, 0xc5, 0x3b, 0x4d, 0xf7, 0x95, 0x39, 0x81, 0xd5, 0x5a, 0x96, 0xa6, 0xdc, 0xff,
                0x99, 0x04, 0xa9, 0x08, 0x42, 0xe5, 0xba, 0xfe, 0xc8, 0x84, 0x0c, 0x2d,
            ],
-            script_code: vec![0x53, 0x63, 0x63, 0x51, 0xac, 0x00, 0x51],
+            script_code: Script(vec![0x53, 0x63, 0x63, 0x51, 0xac, 0x00, 0x51]),
            transparent_input: None,
            hash_type: 1,
            amount: 1345602751504862,
@@ -3369,7 +3369,7 @@ fn zip_0243() {
                0xde, 0x7f, 0x8e, 0x6a, 0x5c, 0x62, 0xa7, 0x77, 0xd1, 0x75, 0x00, 0x2a, 0x13, 0x7d,
                0xe8, 0x5b, 0x88,
            ],
-            script_code: vec![],
+            script_code: Script(vec![]),
            transparent_input: None,
            hash_type: 1,
            amount: 1039204199089370,
@@ -3519,7 +3519,7 @@ fn zip_0243() {
                0xb5, 0x58, 0x02, 0x9a, 0x36, 0x02, 0x4d, 0x2e, 0x79, 0x0f, 0xc6, 0xfd, 0x66, 0x7f,
                0x17, 0x6e, 0x0a, 0xa9, 0x9d, 0xd1, 0xd7, 0x2b, 0x57,
            ],
-            script_code: vec![0x6a, 0x51, 0x65, 0xac],
+            script_code: Script(vec![0x6a, 0x51, 0x65, 0xac]),
            transparent_input: None,
            hash_type: 1,
            amount: 691732482992802,
@@ -3919,7 +3919,7 @@ fn zip_0243() {
                0x30, 0x3a, 0x3a, 0xb9, 0xbb, 0x2e, 0xe3, 0x79, 0xb9, 0xaf, 0xcd, 0x1f, 0x6a, 0x3c,
                0xb9, 0x00, 0x0b, 0xb1, 0x4e,
            ],
-            script_code: vec![0x53, 0x63, 0x63, 0xac, 0x63, 0x52],
+            script_code: Script(vec![0x53, 0x63, 0x63, 0xac, 0x63, 0x52]),
            transparent_input: None,
            hash_type: 1,
            amount: 1152393991505765,
@@ -4083,7 +4083,7 @@ fn zip_0243() {
                0x53, 0xf1, 0xd0, 0xc8, 0x65, 0xa9, 0x4a, 0xa4, 0x56, 0xdc, 0xd1, 0x8a, 0x39, 0xe2,
                0xf5, 0x85, 0xd9, 0xbe, 0xa8,
            ],
-            script_code: vec![0x63, 0x00, 0x6a, 0x53, 0x63, 0x6a, 0xac, 0x00],
+            script_code: Script(vec![0x63, 0x00, 0x6a, 0x53, 0x63, 0x6a, 0xac, 0x00]),
            transparent_input: None,
            hash_type: 1,
            amount: 1788797765223798,
@@ -4681,7 +4681,7 @@ fn zip_0243() {
                0x31, 0xbd, 0x7c, 0x52, 0x22, 0xb6, 0x70, 0x61, 0x6e, 0x4b, 0x6c, 0xa8, 0xa2, 0x35,
                0x50, 0xca, 0xd8, 0xac, 0x0d, 0xdb, 0x76, 0x45, 0xe2, 0xb9, 0x71, 0x3b, 0xe7,
            ],
-            script_code: vec![0x6a, 0x00, 0x00, 0x65, 0x53, 0xac, 0x63, 0x53, 0x63],
+            script_code: Script(vec![0x6a, 0x00, 0x00, 0x65, 0x53, 0xac, 0x63, 0x53, 0x63]),
            transparent_input: None,
            hash_type: 1,
            amount: 1871432121379810,
@@ -5190,7 +5190,7 @@ fn zip_0243() {
                0x1b, 0x48, 0x09, 0x8e, 0xba, 0x2c, 0x2e, 0xc2, 0x0a, 0x0a, 0xc0, 0x44, 0x3b, 0xa8,
                0xe9, 0x48, 0x7b, 0xcf, 0x7d,
            ],
-            script_code: vec![0xac, 0x53, 0x63, 0x52, 0x6a, 0x51, 0xac],
+            script_code: Script(vec![0xac, 0x53, 0x63, 0x52, 0x6a, 0x51, 0xac]),
            transparent_input: None,
            hash_type: 1,
            amount: 1501997449504444,
@@ -5380,7 +5380,7 @@ fn zip_0243() {
                0xfb, 0x34, 0x1e, 0xf5, 0xff, 0xb4, 0x2b, 0xc2, 0xab, 0xc5, 0x08, 0xff, 0x23, 0x12,
                0x48, 0xf2, 0xc2, 0xdc, 0x15, 0x77, 0x0d, 0x33, 0x72, 0x2b, 0x9c, 0x9d, 0xae,
            ],
-            script_code: vec![0xac, 0x65],
+            script_code: Script(vec![0xac, 0x65]),
            transparent_input: Some(0),
            hash_type: 3,
            amount: 391892287957268,
@@ -5398,7 +5398,7 @@ fn zip_0243() {
        let transparent_input = if let Some(n) = tv.transparent_input {
            Some((
                n as usize,
-                Script(tv.script_code),
+                &tv.script_code,
                Amount::from_nonnegative_i64(tv.amount).unwrap(),
            ))
        } else {
Author	SHA1	Message	Date
duke	acff1444ec	Merge pull request 'add fee to builder' (#4 ) from lucretius/librustzcash:sdl into sdl Reviewed-on: https://git.hush.is/hush/librustzcash/pulls/4	2024-01-23 14:53:09 +00:00
lucretius	368b59f937	add fee to builder	2024-01-22 17:14:06 +01:00
Duke Leto	1a0204113d	Merge pull request #2 from DenioD/master sdl librustzcash sync	2020-03-14 07:00:15 -07:00
DenioD	caaee693c4	fix	2019-10-24 01:22:04 +02:00
DenioD	b51e7c055b	fix	2019-10-24 00:43:57 +02:00
DenioD	44a1c3981d	port to hush	2019-10-20 16:03:23 +02:00
DenioD	7510890cf3	proting for Hush	2019-10-20 11:39:27 +02:00
Aditya Kulkarni	188537ea02	Implememt sorting for TxIDs	2019-10-09 11:50:48 -07:00
Aditya Kulkarni	24691f2d50	Revert "Encode expanded spending keys" This reverts commit `0743dadcd0`.	2019-10-02 12:56:02 -07:00
Aditya Kulkarni	0743dadcd0	Encode expanded spending keys	2019-09-24 11:14:13 -07:00
Aditya Kulkarni	37e47981b1	Make Transaction public so we can test it with fake transactions	2019-09-22 20:56:13 -07:00
Aditya Kulkarni	2e22139130	Merge branch 'master' of github.com:adityapk00/librustzcash	2019-09-19 11:17:08 -07:00
Aditya Kulkarni	90b38d0eb1	Add regtest constants	2019-09-19 11:17:03 -07:00
Aditya Kulkarni	3c9b29e47b	Revert "public address from script_sig" This reverts commit `5f274e70d0`.	2019-09-14 10:14:09 -07:00
Aditya Kulkarni	5f274e70d0	public address from script_sig	2019-09-13 18:29:50 -07:00
Aditya Kulkarni	323182c4a5	Implement clone for some structs	2019-09-12 14:26:43 -07:00
Aditya Kulkarni	3ceefdf81c	Create OutPoint from hash and n	2019-09-10 10:34:08 -07:00
Aditya Kulkarni	f8d01215a0	merge serialize fix	2019-09-10 10:18:58 -07:00
adityapk00	5e233620bd	Merge pull request #3 from adityapk00/lightclient-work Lightclient work	2019-09-10 10:01:52 -07:00
Aditya Kulkarni	3ee778de59	transparent inputs should use serialize_der()	2019-09-10 10:01:13 -07:00
Aditya Kulkarni	1056db3bea	Make OutPoint fields pub	2019-09-10 10:00:24 -07:00
Aditya Kulkarni	99d0f78636	Make mod serialize public	2019-09-06 13:37:42 -07:00
Aditya Kulkarni	be84cd8e05	Fix cargo.lock	2019-09-05 13:40:26 -07:00
Aditya Kulkarni	7948bd1bf7	Merge branch 'str4d-transaction-builder-transparent-inputs' into lightclient-work	2019-09-05 13:37:27 -07:00
Aditya Kulkarni	f60d7d331b	Merge branch 'transaction-builder-transparent-inputs' of git://github.com/str4d/librustzcash into str4d-transaction-builder-transparent-inputs	2019-09-05 13:37:08 -07:00
Jack Grigg	1cbeac9d59	zcash_client_sqlite: Support sending to t-addrs	2019-08-29 17:54:26 +01:00
Jack Grigg	1c60a79ec1	Implement TransparentAddress encoding and decoding	2019-08-29 17:53:51 +01:00
Jack Grigg	601e88c633	Chain validity and reorg handling	2019-08-29 17:53:50 +01:00
Jack Grigg	98db781931	Add mainnet support to zcash_client_sqlite via a feature flag	2019-08-29 17:53:49 +01:00
Jack Grigg	2419c6648c	Add security disclaimer to README	2019-08-29 17:53:48 +01:00
Jack Grigg	cfaa0cf067	zcash_client_sqlite::query::get_*_memo_as_utf8()	2019-08-29 17:53:47 +01:00
Jack Grigg	4c1237fa50	zcash_client_sqlite::transact::create_to_address()	2019-08-29 17:53:40 +01:00
Jack Grigg	9a742d25ea	zcash_client_sqlite::scan::scan_cached_blocks()	2019-08-29 17:52:42 +01:00
Jack Grigg	68291090c6	zcash_client_sqlite::query::{get_balance, get_verified_balance}	2019-08-29 17:52:41 +01:00
Jack Grigg	0bf1fad0ed	zcash_client_sqlite::query::get_address()	2019-08-29 17:52:40 +01:00
Jack Grigg	bee4d6a92b	SQLite database structure and initialisation	2019-08-29 17:52:32 +01:00
Jack Grigg	99aef05318	Store witness inside WalletShieldedOutput	2019-08-26 12:41:44 +01:00
Jack Grigg	8cd6666e56	Move cmu and epk parsing onto CompactOutput struct	2019-08-26 12:41:43 +01:00
Jack Grigg	789e2ff216	Travis CI: Build before formatting check cargo fmt does not build the code, and running it in a fresh clone of the codebase will fail because the protobuf code has not been generated.	2019-08-22 15:18:50 +01:00
Jack Grigg	2bafc688ff	Test nullifiers in constant time Checking for spent notes in a block is still not completely constant time, due to filtering out negative results of the constant-time comparison. Part of #84.	2019-08-22 12:52:01 +01:00
Jack Grigg	2774d2730f	Add prevHash field to CompactBlock This enables basic verification of chain validity when CompactBlocks are received without the full header.	2019-08-22 12:50:08 +01:00
Jack Grigg	fd87121244	Compute and store BlockHash inside BlockHeader	2019-08-22 12:50:07 +01:00
Jack Grigg	2e038207f0	Update new witnesses with subsequent transactions in the same block	2019-08-22 12:50:06 +01:00
Jack Grigg	36f1ef62de	Add tx index within block to WalletTx struct	2019-08-22 12:50:05 +01:00
Jack Grigg	c1e6b1844c	Detect change notes while scanning blocks	2019-08-22 12:50:04 +01:00
Jack Grigg	9c51f3426b	Check for spent notes while scanning blocks	2019-08-22 12:50:02 +01:00
Jack Grigg	8b353b3d55	Return the entire note and recipient address when scanning an output	2019-08-22 12:49:28 +01:00
Jack Grigg	c3a30b9597	Increment the commitment tree and witnesses while scanning blocks	2019-08-22 12:49:27 +01:00
Jack Grigg	5ec94b5db5	Parse compact blocks to find wallet transactions	2019-08-22 12:49:22 +01:00
Jack Grigg	2dd2fc620e	Build protobufs for compact formats	2019-08-21 11:04:16 +01:00
Jack Grigg	388a585515	transaction::Builder::add_transparent_input()	2019-08-16 17:13:24 +01:00
Jack Grigg	2a8748582b	Pass Script to signature_hash by reference	2019-08-16 16:22:47 +01:00
Jack Grigg	ff5775418b	legacy::Script::address This is the counterpart to legacy::TransparentAddress::script.	2019-08-16 16:21:59 +01:00
adityapk00	3b7f4faa1b	Merge pull request #1 from zcash/master Pull master	2019-07-10 10:53:05 -07:00