Squashed 'src/secp256k1/' changes from 50cc6ab..1897b8e

1897b8e Merge pull request #229
efc571c Add simple testcases for signing with rfc6979 extra entropy.
1573a10 Add ability to pass extra entropy to rfc6979
3087bc4 Merge pull request #228
d9b9f11 Merge pull request #218
0065a8f Eliminate multiple-returns from secp256k1.c.
354ffa3 Make secp256k1_ec_pubkey_create reject oversized secrets.
27bc131 Silence some warnings from pedantic static analysis tools, improve compatibility with C++.
3b7ea63 Merge pull request #221
f789c5b Merge pull request #215
4bc273b Merge pull request #222
137a8ec Merge pull request #216
7c3771d Disable overlength-strings warnings.
8956111 use 128-bit hex seed
02efd06 Use RFC6979 for test PRNGs
ae55e85 Use faster byteswapping and avoid alignment-increasing casts.
443cd4b Get rid of hex format and some binary conversions
0bada0e Merge #214: Improve signing API documentation & specification
8030d7c Improve signing API documentation & specification
7b2fc1c Merge #213: Removed gotos, which are hard to trace and maintain.
11690d3 Removed gotos, which are hard to trace and maintain.
122a1ec Merge pull request #205
035406d Merge pull request #206
2d4cd53 Merge pull request #161
34b898d Additional comments for the testing PRNG and a seeding fix.
6efd6e7 Some comments explaining some of the constants in the code.
ffccfd2 x86_64 assembly optimization for scalar_4x64
67cbdf0 Merge pull request #207
039723d Benchmarks for all internal operations
6cc8425 Include a comment on secp256k1_ecdsa_sign explaining low-s.
f88343f Merge pull request #203
d61e899 Add group operation counts
2473f17 Merge pull request #202
b5bbce6 Some readme updates, e.g. removal of the GMP field.
f0d851e Merge pull request #201
a0ea884 Merge pull request #200
f735446 Convert the rest of the codebase to C89.
bf2e1ac Convert tests to C89. (also fixes a use of bare "inline" in field)
fc8285f Merge pull request #199
fff412e Merge pull request #197
4be8d6f Centralize the definition of uint128_t and use it uniformly.
d9543c9 Switch scalar code to C89.
fcc48c4 Remove the non-storage cmov
55422b6 Switch ecmult_gen to use storage types
41f8455 Use group element storage type in EC multiplications
e68d720 Add group element storage type
ff889f7 Field storage type
7137be8 Merge pull request #196
0768bd5 Get rid of variable-length hex string conversions
e84e761 Merge pull request #195
792bcdb Covert several more files to C89.
45cdf44 Merge pull request #193
17db09e Merge pull request #194
402878a fix ifdef/ifndef
25b35c7 Convert field code to strict C89 (+ long long, +__int128)
3627437 C89 nits and dead code removal.
a9f350d Merge pull request #191
4732d26 Convert the field/group/ecdsa constant initialization to static consts
19f3e76 Remove unused secp256k1_fe_inner_{start, stop} functions
f1ebfe3 Convert the scalar constant initialization to static consts

git-subtree-dir: src/secp256k1
git-subtree-split: 1897b8e90bbbdcd919427c9a8ae35b420e919d8f
This commit is contained in:
Pieter Wuille
2015-03-27 14:03:36 -07:00
parent 7873633b57
commit 9d09322b41
38 changed files with 2529 additions and 1469 deletions

View File

@@ -13,9 +13,6 @@
#include "num.h"
#include "field.h"
static void secp256k1_fe_inner_start(void) {}
static void secp256k1_fe_inner_stop(void) {}
#ifdef VERIFY
static void secp256k1_fe_verify(const secp256k1_fe_t *a) {
const uint32_t *d = a->n;
@@ -54,8 +51,8 @@ static void secp256k1_fe_normalize(secp256k1_fe_t *r) {
t5 = r->n[5], t6 = r->n[6], t7 = r->n[7], t8 = r->n[8], t9 = r->n[9];
/* Reduce t9 at the start so there will be at most a single carry from the first pass */
uint32_t x = t9 >> 22; t9 &= 0x03FFFFFUL;
uint32_t m;
uint32_t x = t9 >> 22; t9 &= 0x03FFFFFUL;
/* The first pass ensures the magnitude is 1, ... */
t0 += x * 0x3D1UL; t1 += (x << 6);
@@ -140,8 +137,8 @@ static void secp256k1_fe_normalize_var(secp256k1_fe_t *r) {
t5 = r->n[5], t6 = r->n[6], t7 = r->n[7], t8 = r->n[8], t9 = r->n[9];
/* Reduce t9 at the start so there will be at most a single carry from the first pass */
uint32_t x = t9 >> 22; t9 &= 0x03FFFFFUL;
uint32_t m;
uint32_t x = t9 >> 22; t9 &= 0x03FFFFFUL;
/* The first pass ensures the magnitude is 1, ... */
t0 += x * 0x3D1UL; t1 += (x << 6);
@@ -195,12 +192,12 @@ static int secp256k1_fe_normalizes_to_zero(secp256k1_fe_t *r) {
uint32_t t0 = r->n[0], t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4],
t5 = r->n[5], t6 = r->n[6], t7 = r->n[7], t8 = r->n[8], t9 = r->n[9];
/* Reduce t9 at the start so there will be at most a single carry from the first pass */
uint32_t x = t9 >> 22; t9 &= 0x03FFFFFUL;
/* z0 tracks a possible raw value of 0, z1 tracks a possible raw value of P */
uint32_t z0, z1;
/* Reduce t9 at the start so there will be at most a single carry from the first pass */
uint32_t x = t9 >> 22; t9 &= 0x03FFFFFUL;
/* The first pass ensures the magnitude is 1, ... */
t0 += x * 0x3D1UL; t1 += (x << 6);
t1 += (t0 >> 26); t0 &= 0x3FFFFFFUL; z0 = t0; z1 = t0 ^ 0x3D0UL;
@@ -221,23 +218,36 @@ static int secp256k1_fe_normalizes_to_zero(secp256k1_fe_t *r) {
}
static int secp256k1_fe_normalizes_to_zero_var(secp256k1_fe_t *r) {
uint32_t t0 = r->n[0], t9 = r->n[9];
uint32_t t0, t1, t2, t3, t4, t5, t6, t7, t8, t9;
uint32_t z0, z1;
uint32_t x;
t0 = r->n[0];
t9 = r->n[9];
/* Reduce t9 at the start so there will be at most a single carry from the first pass */
uint32_t x = t9 >> 22;
x = t9 >> 22;
/* The first pass ensures the magnitude is 1, ... */
t0 += x * 0x3D1UL;
/* z0 tracks a possible raw value of 0, z1 tracks a possible raw value of P */
uint32_t z0 = t0 & 0x3FFFFFFUL, z1 = z0 ^ 0x3D0UL;
z0 = t0 & 0x3FFFFFFUL;
z1 = z0 ^ 0x3D0UL;
/* Fast return path should catch the majority of cases */
if ((z0 != 0UL) & (z1 != 0x3FFFFFFUL))
return 0;
uint32_t t1 = r->n[1], t2 = r->n[2], t3 = r->n[3], t4 = r->n[4],
t5 = r->n[5], t6 = r->n[6], t7 = r->n[7], t8 = r->n[8];
t1 = r->n[1];
t2 = r->n[2];
t3 = r->n[3];
t4 = r->n[4];
t5 = r->n[5];
t6 = r->n[6];
t7 = r->n[7];
t8 = r->n[8];
t9 &= 0x03FFFFFUL;
t1 += (x << 6);
@@ -269,11 +279,11 @@ SECP256K1_INLINE static void secp256k1_fe_set_int(secp256k1_fe_t *r, int a) {
}
SECP256K1_INLINE static int secp256k1_fe_is_zero(const secp256k1_fe_t *a) {
const uint32_t *t = a->n;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
secp256k1_fe_verify(a);
#endif
const uint32_t *t = a->n;
return (t[0] | t[1] | t[2] | t[3] | t[4] | t[5] | t[6] | t[7] | t[8] | t[9]) == 0;
}
@@ -286,23 +296,25 @@ SECP256K1_INLINE static int secp256k1_fe_is_odd(const secp256k1_fe_t *a) {
}
SECP256K1_INLINE static void secp256k1_fe_clear(secp256k1_fe_t *a) {
int i;
#ifdef VERIFY
a->magnitude = 0;
a->normalized = 1;
#endif
for (int i=0; i<10; i++) {
for (i=0; i<10; i++) {
a->n[i] = 0;
}
}
static int secp256k1_fe_cmp_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b) {
int i;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
VERIFY_CHECK(b->normalized);
secp256k1_fe_verify(a);
secp256k1_fe_verify(b);
#endif
for (int i = 9; i >= 0; i--) {
for (i = 9; i >= 0; i--) {
if (a->n[i] > b->n[i]) return 1;
if (a->n[i] < b->n[i]) return -1;
}
@@ -310,10 +322,12 @@ static int secp256k1_fe_cmp_var(const secp256k1_fe_t *a, const secp256k1_fe_t *b
}
static int secp256k1_fe_set_b32(secp256k1_fe_t *r, const unsigned char *a) {
int i;
r->n[0] = r->n[1] = r->n[2] = r->n[3] = r->n[4] = 0;
r->n[5] = r->n[6] = r->n[7] = r->n[8] = r->n[9] = 0;
for (int i=0; i<32; i++) {
for (int j=0; j<4; j++) {
for (i=0; i<32; i++) {
int j;
for (j=0; j<4; j++) {
int limb = (8*i+2*j)/26;
int shift = (8*i+2*j)%26;
r->n[limb] |= (uint32_t)((a[31-i] >> (2*j)) & 0x3) << shift;
@@ -332,13 +346,15 @@ static int secp256k1_fe_set_b32(secp256k1_fe_t *r, const unsigned char *a) {
/** Convert a field element to a 32-byte big endian value. Requires the input to be normalized */
static void secp256k1_fe_get_b32(unsigned char *r, const secp256k1_fe_t *a) {
int i;
#ifdef VERIFY
VERIFY_CHECK(a->normalized);
secp256k1_fe_verify(a);
#endif
for (int i=0; i<32; i++) {
for (i=0; i<32; i++) {
int j;
int c = 0;
for (int j=0; j<4; j++) {
for (j=0; j<4; j++) {
int limb = (8*i+2*j)/26;
int shift = (8*i+2*j)%26;
c |= ((a->n[limb] >> shift) & 0x3) << (2 * j);
@@ -415,6 +431,11 @@ SECP256K1_INLINE static void secp256k1_fe_add(secp256k1_fe_t *r, const secp256k1
#endif
SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t *a, const uint32_t * SECP256K1_RESTRICT b) {
uint64_t c, d;
uint64_t u0, u1, u2, u3, u4, u5, u6, u7, u8;
uint32_t t9, t1, t0, t2, t3, t4, t5, t6, t7;
const uint32_t M = 0x3FFFFFFUL, R0 = 0x3D10UL, R1 = 0x400UL;
VERIFY_BITS(a[0], 30);
VERIFY_BITS(a[1], 30);
VERIFY_BITS(a[2], 30);
@@ -436,14 +457,11 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
VERIFY_BITS(b[8], 30);
VERIFY_BITS(b[9], 26);
const uint32_t M = 0x3FFFFFFUL, R0 = 0x3D10UL, R1 = 0x400UL;
/** [... a b c] is a shorthand for ... + a<<52 + b<<26 + c<<0 mod n.
* px is a shorthand for sum(a[i]*b[x-i], i=0..x).
* Note that [x 0 0 0 0 0 0 0 0 0 0] = [x*R1 x*R0].
*/
uint64_t c, d;
d = (uint64_t)a[0] * b[9]
+ (uint64_t)a[1] * b[8]
+ (uint64_t)a[2] * b[7]
@@ -456,7 +474,7 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[0];
/* VERIFY_BITS(d, 64); */
/* [d 0 0 0 0 0 0 0 0 0] = [p9 0 0 0 0 0 0 0 0 0] */
uint32_t t9 = d & M; d >>= 26;
t9 = d & M; d >>= 26;
VERIFY_BITS(t9, 26);
VERIFY_BITS(d, 38);
/* [d t9 0 0 0 0 0 0 0 0 0] = [p9 0 0 0 0 0 0 0 0 0] */
@@ -475,12 +493,12 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[1];
VERIFY_BITS(d, 63);
/* [d t9 0 0 0 0 0 0 0 0 c] = [p10 p9 0 0 0 0 0 0 0 0 p0] */
uint64_t u0 = d & M; d >>= 26; c += u0 * R0;
u0 = d & M; d >>= 26; c += u0 * R0;
VERIFY_BITS(u0, 26);
VERIFY_BITS(d, 37);
VERIFY_BITS(c, 61);
/* [d u0 t9 0 0 0 0 0 0 0 0 c-u0*R0] = [p10 p9 0 0 0 0 0 0 0 0 p0] */
uint32_t t0 = c & M; c >>= 26; c += u0 * R1;
t0 = c & M; c >>= 26; c += u0 * R1;
VERIFY_BITS(t0, 26);
VERIFY_BITS(c, 37);
/* [d u0 t9 0 0 0 0 0 0 0 c-u0*R1 t0-u0*R0] = [p10 p9 0 0 0 0 0 0 0 0 p0] */
@@ -500,12 +518,12 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[2];
VERIFY_BITS(d, 63);
/* [d 0 t9 0 0 0 0 0 0 0 c t0] = [p11 p10 p9 0 0 0 0 0 0 0 p1 p0] */
uint64_t u1 = d & M; d >>= 26; c += u1 * R0;
u1 = d & M; d >>= 26; c += u1 * R0;
VERIFY_BITS(u1, 26);
VERIFY_BITS(d, 37);
VERIFY_BITS(c, 63);
/* [d u1 0 t9 0 0 0 0 0 0 0 c-u1*R0 t0] = [p11 p10 p9 0 0 0 0 0 0 0 p1 p0] */
uint32_t t1 = c & M; c >>= 26; c += u1 * R1;
t1 = c & M; c >>= 26; c += u1 * R1;
VERIFY_BITS(t1, 26);
VERIFY_BITS(c, 38);
/* [d u1 0 t9 0 0 0 0 0 0 c-u1*R1 t1-u1*R0 t0] = [p11 p10 p9 0 0 0 0 0 0 0 p1 p0] */
@@ -525,12 +543,12 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[3];
VERIFY_BITS(d, 63);
/* [d 0 0 t9 0 0 0 0 0 0 c t1 t0] = [p12 p11 p10 p9 0 0 0 0 0 0 p2 p1 p0] */
uint64_t u2 = d & M; d >>= 26; c += u2 * R0;
u2 = d & M; d >>= 26; c += u2 * R0;
VERIFY_BITS(u2, 26);
VERIFY_BITS(d, 37);
VERIFY_BITS(c, 63);
/* [d u2 0 0 t9 0 0 0 0 0 0 c-u2*R0 t1 t0] = [p12 p11 p10 p9 0 0 0 0 0 0 p2 p1 p0] */
uint32_t t2 = c & M; c >>= 26; c += u2 * R1;
t2 = c & M; c >>= 26; c += u2 * R1;
VERIFY_BITS(t2, 26);
VERIFY_BITS(c, 38);
/* [d u2 0 0 t9 0 0 0 0 0 c-u2*R1 t2-u2*R0 t1 t0] = [p12 p11 p10 p9 0 0 0 0 0 0 p2 p1 p0] */
@@ -550,12 +568,12 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[4];
VERIFY_BITS(d, 63);
/* [d 0 0 0 t9 0 0 0 0 0 c t2 t1 t0] = [p13 p12 p11 p10 p9 0 0 0 0 0 p3 p2 p1 p0] */
uint64_t u3 = d & M; d >>= 26; c += u3 * R0;
u3 = d & M; d >>= 26; c += u3 * R0;
VERIFY_BITS(u3, 26);
VERIFY_BITS(d, 37);
/* VERIFY_BITS(c, 64); */
/* [d u3 0 0 0 t9 0 0 0 0 0 c-u3*R0 t2 t1 t0] = [p13 p12 p11 p10 p9 0 0 0 0 0 p3 p2 p1 p0] */
uint32_t t3 = c & M; c >>= 26; c += u3 * R1;
t3 = c & M; c >>= 26; c += u3 * R1;
VERIFY_BITS(t3, 26);
VERIFY_BITS(c, 39);
/* [d u3 0 0 0 t9 0 0 0 0 c-u3*R1 t3-u3*R0 t2 t1 t0] = [p13 p12 p11 p10 p9 0 0 0 0 0 p3 p2 p1 p0] */
@@ -575,12 +593,12 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[5];
VERIFY_BITS(d, 62);
/* [d 0 0 0 0 t9 0 0 0 0 c t3 t2 t1 t0] = [p14 p13 p12 p11 p10 p9 0 0 0 0 p4 p3 p2 p1 p0] */
uint64_t u4 = d & M; d >>= 26; c += u4 * R0;
u4 = d & M; d >>= 26; c += u4 * R0;
VERIFY_BITS(u4, 26);
VERIFY_BITS(d, 36);
/* VERIFY_BITS(c, 64); */
/* [d u4 0 0 0 0 t9 0 0 0 0 c-u4*R0 t3 t2 t1 t0] = [p14 p13 p12 p11 p10 p9 0 0 0 0 p4 p3 p2 p1 p0] */
uint32_t t4 = c & M; c >>= 26; c += u4 * R1;
t4 = c & M; c >>= 26; c += u4 * R1;
VERIFY_BITS(t4, 26);
VERIFY_BITS(c, 39);
/* [d u4 0 0 0 0 t9 0 0 0 c-u4*R1 t4-u4*R0 t3 t2 t1 t0] = [p14 p13 p12 p11 p10 p9 0 0 0 0 p4 p3 p2 p1 p0] */
@@ -600,12 +618,12 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[6];
VERIFY_BITS(d, 62);
/* [d 0 0 0 0 0 t9 0 0 0 c t4 t3 t2 t1 t0] = [p15 p14 p13 p12 p11 p10 p9 0 0 0 p5 p4 p3 p2 p1 p0] */
uint64_t u5 = d & M; d >>= 26; c += u5 * R0;
u5 = d & M; d >>= 26; c += u5 * R0;
VERIFY_BITS(u5, 26);
VERIFY_BITS(d, 36);
/* VERIFY_BITS(c, 64); */
/* [d u5 0 0 0 0 0 t9 0 0 0 c-u5*R0 t4 t3 t2 t1 t0] = [p15 p14 p13 p12 p11 p10 p9 0 0 0 p5 p4 p3 p2 p1 p0] */
uint32_t t5 = c & M; c >>= 26; c += u5 * R1;
t5 = c & M; c >>= 26; c += u5 * R1;
VERIFY_BITS(t5, 26);
VERIFY_BITS(c, 39);
/* [d u5 0 0 0 0 0 t9 0 0 c-u5*R1 t5-u5*R0 t4 t3 t2 t1 t0] = [p15 p14 p13 p12 p11 p10 p9 0 0 0 p5 p4 p3 p2 p1 p0] */
@@ -625,12 +643,12 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[7];
VERIFY_BITS(d, 61);
/* [d 0 0 0 0 0 0 t9 0 0 c t5 t4 t3 t2 t1 t0] = [p16 p15 p14 p13 p12 p11 p10 p9 0 0 p6 p5 p4 p3 p2 p1 p0] */
uint64_t u6 = d & M; d >>= 26; c += u6 * R0;
u6 = d & M; d >>= 26; c += u6 * R0;
VERIFY_BITS(u6, 26);
VERIFY_BITS(d, 35);
/* VERIFY_BITS(c, 64); */
/* [d u6 0 0 0 0 0 0 t9 0 0 c-u6*R0 t5 t4 t3 t2 t1 t0] = [p16 p15 p14 p13 p12 p11 p10 p9 0 0 p6 p5 p4 p3 p2 p1 p0] */
uint32_t t6 = c & M; c >>= 26; c += u6 * R1;
t6 = c & M; c >>= 26; c += u6 * R1;
VERIFY_BITS(t6, 26);
VERIFY_BITS(c, 39);
/* [d u6 0 0 0 0 0 0 t9 0 c-u6*R1 t6-u6*R0 t5 t4 t3 t2 t1 t0] = [p16 p15 p14 p13 p12 p11 p10 p9 0 0 p6 p5 p4 p3 p2 p1 p0] */
@@ -651,13 +669,13 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[9] * b[8];
VERIFY_BITS(d, 58);
/* [d 0 0 0 0 0 0 0 t9 0 c t6 t5 t4 t3 t2 t1 t0] = [p17 p16 p15 p14 p13 p12 p11 p10 p9 0 p7 p6 p5 p4 p3 p2 p1 p0] */
uint64_t u7 = d & M; d >>= 26; c += u7 * R0;
u7 = d & M; d >>= 26; c += u7 * R0;
VERIFY_BITS(u7, 26);
VERIFY_BITS(d, 32);
/* VERIFY_BITS(c, 64); */
VERIFY_CHECK(c <= 0x800001703FFFC2F7ULL);
/* [d u7 0 0 0 0 0 0 0 t9 0 c-u7*R0 t6 t5 t4 t3 t2 t1 t0] = [p17 p16 p15 p14 p13 p12 p11 p10 p9 0 p7 p6 p5 p4 p3 p2 p1 p0] */
uint32_t t7 = c & M; c >>= 26; c += u7 * R1;
t7 = c & M; c >>= 26; c += u7 * R1;
VERIFY_BITS(t7, 26);
VERIFY_BITS(c, 38);
/* [d u7 0 0 0 0 0 0 0 t9 c-u7*R1 t7-u7*R0 t6 t5 t4 t3 t2 t1 t0] = [p17 p16 p15 p14 p13 p12 p11 p10 p9 0 p7 p6 p5 p4 p3 p2 p1 p0] */
@@ -678,7 +696,7 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
d += (uint64_t)a[9] * b[9];
VERIFY_BITS(d, 57);
/* [d 0 0 0 0 0 0 0 0 t9 c t7 t6 t5 t4 t3 t2 t1 t0] = [p18 p17 p16 p15 p14 p13 p12 p11 p10 p9 p8 p7 p6 p5 p4 p3 p2 p1 p0] */
uint64_t u8 = d & M; d >>= 26; c += u8 * R0;
u8 = d & M; d >>= 26; c += u8 * R0;
VERIFY_BITS(u8, 26);
VERIFY_BITS(d, 31);
/* VERIFY_BITS(c, 64); */
@@ -742,6 +760,11 @@ SECP256K1_INLINE static void secp256k1_fe_mul_inner(uint32_t *r, const uint32_t
}
SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t *a) {
uint64_t c, d;
uint64_t u0, u1, u2, u3, u4, u5, u6, u7, u8;
uint32_t t9, t0, t1, t2, t3, t4, t5, t6, t7;
const uint32_t M = 0x3FFFFFFUL, R0 = 0x3D10UL, R1 = 0x400UL;
VERIFY_BITS(a[0], 30);
VERIFY_BITS(a[1], 30);
VERIFY_BITS(a[2], 30);
@@ -753,14 +776,11 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
VERIFY_BITS(a[8], 30);
VERIFY_BITS(a[9], 26);
const uint32_t M = 0x3FFFFFFUL, R0 = 0x3D10UL, R1 = 0x400UL;
/** [... a b c] is a shorthand for ... + a<<52 + b<<26 + c<<0 mod n.
* px is a shorthand for sum(a[i]*a[x-i], i=0..x).
* Note that [x 0 0 0 0 0 0 0 0 0 0] = [x*R1 x*R0].
*/
uint64_t c, d;
d = (uint64_t)(a[0]*2) * a[9]
+ (uint64_t)(a[1]*2) * a[8]
+ (uint64_t)(a[2]*2) * a[7]
@@ -768,7 +788,7 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
+ (uint64_t)(a[4]*2) * a[5];
/* VERIFY_BITS(d, 64); */
/* [d 0 0 0 0 0 0 0 0 0] = [p9 0 0 0 0 0 0 0 0 0] */
uint32_t t9 = d & M; d >>= 26;
t9 = d & M; d >>= 26;
VERIFY_BITS(t9, 26);
VERIFY_BITS(d, 38);
/* [d t9 0 0 0 0 0 0 0 0 0] = [p9 0 0 0 0 0 0 0 0 0] */
@@ -783,12 +803,12 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[5] * a[5];
VERIFY_BITS(d, 63);
/* [d t9 0 0 0 0 0 0 0 0 c] = [p10 p9 0 0 0 0 0 0 0 0 p0] */
uint64_t u0 = d & M; d >>= 26; c += u0 * R0;
u0 = d & M; d >>= 26; c += u0 * R0;
VERIFY_BITS(u0, 26);
VERIFY_BITS(d, 37);
VERIFY_BITS(c, 61);
/* [d u0 t9 0 0 0 0 0 0 0 0 c-u0*R0] = [p10 p9 0 0 0 0 0 0 0 0 p0] */
uint32_t t0 = c & M; c >>= 26; c += u0 * R1;
t0 = c & M; c >>= 26; c += u0 * R1;
VERIFY_BITS(t0, 26);
VERIFY_BITS(c, 37);
/* [d u0 t9 0 0 0 0 0 0 0 c-u0*R1 t0-u0*R0] = [p10 p9 0 0 0 0 0 0 0 0 p0] */
@@ -803,12 +823,12 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
+ (uint64_t)(a[5]*2) * a[6];
VERIFY_BITS(d, 63);
/* [d 0 t9 0 0 0 0 0 0 0 c t0] = [p11 p10 p9 0 0 0 0 0 0 0 p1 p0] */
uint64_t u1 = d & M; d >>= 26; c += u1 * R0;
u1 = d & M; d >>= 26; c += u1 * R0;
VERIFY_BITS(u1, 26);
VERIFY_BITS(d, 37);
VERIFY_BITS(c, 63);
/* [d u1 0 t9 0 0 0 0 0 0 0 c-u1*R0 t0] = [p11 p10 p9 0 0 0 0 0 0 0 p1 p0] */
uint32_t t1 = c & M; c >>= 26; c += u1 * R1;
t1 = c & M; c >>= 26; c += u1 * R1;
VERIFY_BITS(t1, 26);
VERIFY_BITS(c, 38);
/* [d u1 0 t9 0 0 0 0 0 0 c-u1*R1 t1-u1*R0 t0] = [p11 p10 p9 0 0 0 0 0 0 0 p1 p0] */
@@ -824,12 +844,12 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[6] * a[6];
VERIFY_BITS(d, 63);
/* [d 0 0 t9 0 0 0 0 0 0 c t1 t0] = [p12 p11 p10 p9 0 0 0 0 0 0 p2 p1 p0] */
uint64_t u2 = d & M; d >>= 26; c += u2 * R0;
u2 = d & M; d >>= 26; c += u2 * R0;
VERIFY_BITS(u2, 26);
VERIFY_BITS(d, 37);
VERIFY_BITS(c, 63);
/* [d u2 0 0 t9 0 0 0 0 0 0 c-u2*R0 t1 t0] = [p12 p11 p10 p9 0 0 0 0 0 0 p2 p1 p0] */
uint32_t t2 = c & M; c >>= 26; c += u2 * R1;
t2 = c & M; c >>= 26; c += u2 * R1;
VERIFY_BITS(t2, 26);
VERIFY_BITS(c, 38);
/* [d u2 0 0 t9 0 0 0 0 0 c-u2*R1 t2-u2*R0 t1 t0] = [p12 p11 p10 p9 0 0 0 0 0 0 p2 p1 p0] */
@@ -844,12 +864,12 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
+ (uint64_t)(a[6]*2) * a[7];
VERIFY_BITS(d, 63);
/* [d 0 0 0 t9 0 0 0 0 0 c t2 t1 t0] = [p13 p12 p11 p10 p9 0 0 0 0 0 p3 p2 p1 p0] */
uint64_t u3 = d & M; d >>= 26; c += u3 * R0;
u3 = d & M; d >>= 26; c += u3 * R0;
VERIFY_BITS(u3, 26);
VERIFY_BITS(d, 37);
/* VERIFY_BITS(c, 64); */
/* [d u3 0 0 0 t9 0 0 0 0 0 c-u3*R0 t2 t1 t0] = [p13 p12 p11 p10 p9 0 0 0 0 0 p3 p2 p1 p0] */
uint32_t t3 = c & M; c >>= 26; c += u3 * R1;
t3 = c & M; c >>= 26; c += u3 * R1;
VERIFY_BITS(t3, 26);
VERIFY_BITS(c, 39);
/* [d u3 0 0 0 t9 0 0 0 0 c-u3*R1 t3-u3*R0 t2 t1 t0] = [p13 p12 p11 p10 p9 0 0 0 0 0 p3 p2 p1 p0] */
@@ -865,12 +885,12 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[7] * a[7];
VERIFY_BITS(d, 62);
/* [d 0 0 0 0 t9 0 0 0 0 c t3 t2 t1 t0] = [p14 p13 p12 p11 p10 p9 0 0 0 0 p4 p3 p2 p1 p0] */
uint64_t u4 = d & M; d >>= 26; c += u4 * R0;
u4 = d & M; d >>= 26; c += u4 * R0;
VERIFY_BITS(u4, 26);
VERIFY_BITS(d, 36);
/* VERIFY_BITS(c, 64); */
/* [d u4 0 0 0 0 t9 0 0 0 0 c-u4*R0 t3 t2 t1 t0] = [p14 p13 p12 p11 p10 p9 0 0 0 0 p4 p3 p2 p1 p0] */
uint32_t t4 = c & M; c >>= 26; c += u4 * R1;
t4 = c & M; c >>= 26; c += u4 * R1;
VERIFY_BITS(t4, 26);
VERIFY_BITS(c, 39);
/* [d u4 0 0 0 0 t9 0 0 0 c-u4*R1 t4-u4*R0 t3 t2 t1 t0] = [p14 p13 p12 p11 p10 p9 0 0 0 0 p4 p3 p2 p1 p0] */
@@ -885,12 +905,12 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
+ (uint64_t)(a[7]*2) * a[8];
VERIFY_BITS(d, 62);
/* [d 0 0 0 0 0 t9 0 0 0 c t4 t3 t2 t1 t0] = [p15 p14 p13 p12 p11 p10 p9 0 0 0 p5 p4 p3 p2 p1 p0] */
uint64_t u5 = d & M; d >>= 26; c += u5 * R0;
u5 = d & M; d >>= 26; c += u5 * R0;
VERIFY_BITS(u5, 26);
VERIFY_BITS(d, 36);
/* VERIFY_BITS(c, 64); */
/* [d u5 0 0 0 0 0 t9 0 0 0 c-u5*R0 t4 t3 t2 t1 t0] = [p15 p14 p13 p12 p11 p10 p9 0 0 0 p5 p4 p3 p2 p1 p0] */
uint32_t t5 = c & M; c >>= 26; c += u5 * R1;
t5 = c & M; c >>= 26; c += u5 * R1;
VERIFY_BITS(t5, 26);
VERIFY_BITS(c, 39);
/* [d u5 0 0 0 0 0 t9 0 0 c-u5*R1 t5-u5*R0 t4 t3 t2 t1 t0] = [p15 p14 p13 p12 p11 p10 p9 0 0 0 p5 p4 p3 p2 p1 p0] */
@@ -906,12 +926,12 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
+ (uint64_t)a[8] * a[8];
VERIFY_BITS(d, 61);
/* [d 0 0 0 0 0 0 t9 0 0 c t5 t4 t3 t2 t1 t0] = [p16 p15 p14 p13 p12 p11 p10 p9 0 0 p6 p5 p4 p3 p2 p1 p0] */
uint64_t u6 = d & M; d >>= 26; c += u6 * R0;
u6 = d & M; d >>= 26; c += u6 * R0;
VERIFY_BITS(u6, 26);
VERIFY_BITS(d, 35);
/* VERIFY_BITS(c, 64); */
/* [d u6 0 0 0 0 0 0 t9 0 0 c-u6*R0 t5 t4 t3 t2 t1 t0] = [p16 p15 p14 p13 p12 p11 p10 p9 0 0 p6 p5 p4 p3 p2 p1 p0] */
uint32_t t6 = c & M; c >>= 26; c += u6 * R1;
t6 = c & M; c >>= 26; c += u6 * R1;
VERIFY_BITS(t6, 26);
VERIFY_BITS(c, 39);
/* [d u6 0 0 0 0 0 0 t9 0 c-u6*R1 t6-u6*R0 t5 t4 t3 t2 t1 t0] = [p16 p15 p14 p13 p12 p11 p10 p9 0 0 p6 p5 p4 p3 p2 p1 p0] */
@@ -927,13 +947,13 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
d += (uint64_t)(a[8]*2) * a[9];
VERIFY_BITS(d, 58);
/* [d 0 0 0 0 0 0 0 t9 0 c t6 t5 t4 t3 t2 t1 t0] = [p17 p16 p15 p14 p13 p12 p11 p10 p9 0 p7 p6 p5 p4 p3 p2 p1 p0] */
uint64_t u7 = d & M; d >>= 26; c += u7 * R0;
u7 = d & M; d >>= 26; c += u7 * R0;
VERIFY_BITS(u7, 26);
VERIFY_BITS(d, 32);
/* VERIFY_BITS(c, 64); */
VERIFY_CHECK(c <= 0x800001703FFFC2F7ULL);
/* [d u7 0 0 0 0 0 0 0 t9 0 c-u7*R0 t6 t5 t4 t3 t2 t1 t0] = [p17 p16 p15 p14 p13 p12 p11 p10 p9 0 p7 p6 p5 p4 p3 p2 p1 p0] */
uint32_t t7 = c & M; c >>= 26; c += u7 * R1;
t7 = c & M; c >>= 26; c += u7 * R1;
VERIFY_BITS(t7, 26);
VERIFY_BITS(c, 38);
/* [d u7 0 0 0 0 0 0 0 t9 c-u7*R1 t7-u7*R0 t6 t5 t4 t3 t2 t1 t0] = [p17 p16 p15 p14 p13 p12 p11 p10 p9 0 p7 p6 p5 p4 p3 p2 p1 p0] */
@@ -950,7 +970,7 @@ SECP256K1_INLINE static void secp256k1_fe_sqr_inner(uint32_t *r, const uint32_t
d += (uint64_t)a[9] * a[9];
VERIFY_BITS(d, 57);
/* [d 0 0 0 0 0 0 0 0 t9 c t7 t6 t5 t4 t3 t2 t1 t0] = [p18 p17 p16 p15 p14 p13 p12 p11 p10 p9 p8 p7 p6 p5 p4 p3 p2 p1 p0] */
uint64_t u8 = d & M; d >>= 26; c += u8 * R0;
u8 = d & M; d >>= 26; c += u8 * R0;
VERIFY_BITS(u8, 26);
VERIFY_BITS(d, 31);
/* VERIFY_BITS(c, 64); */
@@ -1043,8 +1063,10 @@ static void secp256k1_fe_sqr(secp256k1_fe_t *r, const secp256k1_fe_t *a) {
#endif
}
static void secp256k1_fe_cmov(secp256k1_fe_t *r, const secp256k1_fe_t *a, int flag) {
uint32_t mask0 = flag + ~((uint32_t)0), mask1 = ~mask0;
static SECP256K1_INLINE void secp256k1_fe_storage_cmov(secp256k1_fe_storage_t *r, const secp256k1_fe_storage_t *a, int flag) {
uint32_t mask0, mask1;
mask0 = flag + ~((uint32_t)0);
mask1 = ~mask0;
r->n[0] = (r->n[0] & mask0) | (a->n[0] & mask1);
r->n[1] = (r->n[1] & mask0) | (a->n[1] & mask1);
r->n[2] = (r->n[2] & mask0) | (a->n[2] & mask1);
@@ -1053,13 +1075,36 @@ static void secp256k1_fe_cmov(secp256k1_fe_t *r, const secp256k1_fe_t *a, int fl
r->n[5] = (r->n[5] & mask0) | (a->n[5] & mask1);
r->n[6] = (r->n[6] & mask0) | (a->n[6] & mask1);
r->n[7] = (r->n[7] & mask0) | (a->n[7] & mask1);
r->n[8] = (r->n[8] & mask0) | (a->n[8] & mask1);
r->n[9] = (r->n[9] & mask0) | (a->n[9] & mask1);
}
static void secp256k1_fe_to_storage(secp256k1_fe_storage_t *r, const secp256k1_fe_t *a) {
#ifdef VERIFY
if (flag) {
r->magnitude = a->magnitude;
r->normalized = a->normalized;
}
VERIFY_CHECK(a->normalized);
#endif
r->n[0] = a->n[0] | a->n[1] << 26;
r->n[1] = a->n[1] >> 6 | a->n[2] << 20;
r->n[2] = a->n[2] >> 12 | a->n[3] << 14;
r->n[3] = a->n[3] >> 18 | a->n[4] << 8;
r->n[4] = a->n[4] >> 24 | a->n[5] << 2 | a->n[6] << 28;
r->n[5] = a->n[6] >> 4 | a->n[7] << 22;
r->n[6] = a->n[7] >> 10 | a->n[8] << 16;
r->n[7] = a->n[8] >> 16 | a->n[9] << 10;
}
static SECP256K1_INLINE void secp256k1_fe_from_storage(secp256k1_fe_t *r, const secp256k1_fe_storage_t *a) {
r->n[0] = a->n[0] & 0x3FFFFFFUL;
r->n[1] = a->n[0] >> 26 | ((a->n[1] << 6) & 0x3FFFFFFUL);
r->n[2] = a->n[1] >> 20 | ((a->n[2] << 12) & 0x3FFFFFFUL);
r->n[3] = a->n[2] >> 14 | ((a->n[3] << 18) & 0x3FFFFFFUL);
r->n[4] = a->n[3] >> 8 | ((a->n[4] << 24) & 0x3FFFFFFUL);
r->n[5] = (a->n[4] >> 2) & 0x3FFFFFFUL;
r->n[6] = a->n[4] >> 28 | ((a->n[5] << 4) & 0x3FFFFFFUL);
r->n[7] = a->n[5] >> 22 | ((a->n[6] << 10) & 0x3FFFFFFUL);
r->n[8] = a->n[6] >> 16 | ((a->n[7] << 16) & 0x3FFFFFFUL);
r->n[9] = a->n[7] >> 10;
#ifdef VERIFY
r->magnitude = 1;
r->normalized = 1;
#endif
}