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

@@ -91,8 +91,9 @@ SECP256K1_INLINE static int secp256k1_scalar_check_overflow(const secp256k1_scal
}
SECP256K1_INLINE static int secp256k1_scalar_reduce(secp256k1_scalar_t *r, uint32_t overflow) {
uint64_t t;
VERIFY_CHECK(overflow <= 1);
uint64_t t = (uint64_t)r->d[0] + overflow * SECP256K1_N_C_0;
t = (uint64_t)r->d[0] + overflow * SECP256K1_N_C_0;
r->d[0] = t & 0xFFFFFFFFUL; t >>= 32;
t += (uint64_t)r->d[1] + overflow * SECP256K1_N_C_1;
r->d[1] = t & 0xFFFFFFFFUL; t >>= 32;
@@ -112,6 +113,7 @@ SECP256K1_INLINE static int secp256k1_scalar_reduce(secp256k1_scalar_t *r, uint3
}
static int secp256k1_scalar_add(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
int overflow;
uint64_t t = (uint64_t)a->d[0] + b->d[0];
r->d[0] = t & 0xFFFFFFFFULL; t >>= 32;
t += (uint64_t)a->d[1] + b->d[1];
@@ -128,15 +130,16 @@ static int secp256k1_scalar_add(secp256k1_scalar_t *r, const secp256k1_scalar_t
r->d[6] = t & 0xFFFFFFFFULL; t >>= 32;
t += (uint64_t)a->d[7] + b->d[7];
r->d[7] = t & 0xFFFFFFFFULL; t >>= 32;
int overflow = t + secp256k1_scalar_check_overflow(r);
overflow = t + secp256k1_scalar_check_overflow(r);
VERIFY_CHECK(overflow == 0 || overflow == 1);
secp256k1_scalar_reduce(r, overflow);
return overflow;
}
static void secp256k1_scalar_add_bit(secp256k1_scalar_t *r, unsigned int bit) {
uint64_t t;
VERIFY_CHECK(bit < 256);
uint64_t t = (uint64_t)r->d[0] + (((uint32_t)((bit >> 5) == 0)) << (bit & 0x1F));
t = (uint64_t)r->d[0] + (((uint32_t)((bit >> 5) == 0)) << (bit & 0x1F));
r->d[0] = t & 0xFFFFFFFFULL; t >>= 32;
t += (uint64_t)r->d[1] + (((uint32_t)((bit >> 5) == 1)) << (bit & 0x1F));
r->d[1] = t & 0xFFFFFFFFULL; t >>= 32;
@@ -159,6 +162,7 @@ static void secp256k1_scalar_add_bit(secp256k1_scalar_t *r, unsigned int bit) {
}
static void secp256k1_scalar_set_b32(secp256k1_scalar_t *r, const unsigned char *b32, int *overflow) {
int over;
r->d[0] = (uint32_t)b32[31] | (uint32_t)b32[30] << 8 | (uint32_t)b32[29] << 16 | (uint32_t)b32[28] << 24;
r->d[1] = (uint32_t)b32[27] | (uint32_t)b32[26] << 8 | (uint32_t)b32[25] << 16 | (uint32_t)b32[24] << 24;
r->d[2] = (uint32_t)b32[23] | (uint32_t)b32[22] << 8 | (uint32_t)b32[21] << 16 | (uint32_t)b32[20] << 24;
@@ -167,7 +171,7 @@ static void secp256k1_scalar_set_b32(secp256k1_scalar_t *r, const unsigned char
r->d[5] = (uint32_t)b32[11] | (uint32_t)b32[10] << 8 | (uint32_t)b32[9] << 16 | (uint32_t)b32[8] << 24;
r->d[6] = (uint32_t)b32[7] | (uint32_t)b32[6] << 8 | (uint32_t)b32[5] << 16 | (uint32_t)b32[4] << 24;
r->d[7] = (uint32_t)b32[3] | (uint32_t)b32[2] << 8 | (uint32_t)b32[1] << 16 | (uint32_t)b32[0] << 24;
int over = secp256k1_scalar_reduce(r, secp256k1_scalar_check_overflow(r));
over = secp256k1_scalar_reduce(r, secp256k1_scalar_check_overflow(r));
if (overflow) {
*overflow = over;
}
@@ -263,16 +267,16 @@ static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
/** Add 2*a*b to the number defined by (c0,c1,c2). c2 must never overflow. */
#define muladd2(a,b) { \
uint32_t tl, th; \
uint32_t tl, th, th2, tl2; \
{ \
uint64_t t = (uint64_t)a * b; \
th = t >> 32; /* at most 0xFFFFFFFE */ \
tl = t; \
} \
uint32_t th2 = th + th; /* at most 0xFFFFFFFE (in case th was 0x7FFFFFFF) */ \
th2 = th + th; /* at most 0xFFFFFFFE (in case th was 0x7FFFFFFF) */ \
c2 += (th2 < th) ? 1 : 0; /* never overflows by contract (verified the next line) */ \
VERIFY_CHECK((th2 >= th) || (c2 != 0)); \
uint32_t tl2 = tl + tl; /* at most 0xFFFFFFFE (in case the lowest 63 bits of tl were 0x7FFFFFFF) */ \
tl2 = tl + tl; /* at most 0xFFFFFFFE (in case the lowest 63 bits of tl were 0x7FFFFFFF) */ \
th2 += (tl2 < tl) ? 1 : 0; /* at most 0xFFFFFFFF */ \
c0 += tl2; /* overflow is handled on the next line */ \
th2 += (c0 < tl2) ? 1 : 0; /* second overflow is handled on the next line */ \
@@ -285,8 +289,9 @@ static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
/** Add a to the number defined by (c0,c1,c2). c2 must never overflow. */
#define sumadd(a) { \
unsigned int over; \
c0 += (a); /* overflow is handled on the next line */ \
unsigned int over = (c0 < (a)) ? 1 : 0; \
over = (c0 < (a)) ? 1 : 0; \
c1 += over; /* overflow is handled on the next line */ \
c2 += (c1 < over) ? 1 : 0; /* never overflows by contract */ \
}
@@ -316,7 +321,10 @@ static int secp256k1_scalar_is_high(const secp256k1_scalar_t *a) {
}
static void secp256k1_scalar_reduce_512(secp256k1_scalar_t *r, const uint32_t *l) {
uint64_t c;
uint32_t n0 = l[8], n1 = l[9], n2 = l[10], n3 = l[11], n4 = l[12], n5 = l[13], n6 = l[14], n7 = l[15];
uint32_t m0, m1, m2, m3, m4, m5, m6, m7, m8, m9, m10, m11, m12;
uint32_t p0, p1, p2, p3, p4, p5, p6, p7, p8;
/* 96 bit accumulator. */
uint32_t c0, c1, c2;
@@ -325,115 +333,115 @@ static void secp256k1_scalar_reduce_512(secp256k1_scalar_t *r, const uint32_t *l
/* m[0..12] = l[0..7] + n[0..7] * SECP256K1_N_C. */
c0 = l[0]; c1 = 0; c2 = 0;
muladd_fast(n0, SECP256K1_N_C_0);
uint32_t m0; extract_fast(m0);
extract_fast(m0);
sumadd_fast(l[1]);
muladd(n1, SECP256K1_N_C_0);
muladd(n0, SECP256K1_N_C_1);
uint32_t m1; extract(m1);
extract(m1);
sumadd(l[2]);
muladd(n2, SECP256K1_N_C_0);
muladd(n1, SECP256K1_N_C_1);
muladd(n0, SECP256K1_N_C_2);
uint32_t m2; extract(m2);
extract(m2);
sumadd(l[3]);
muladd(n3, SECP256K1_N_C_0);
muladd(n2, SECP256K1_N_C_1);
muladd(n1, SECP256K1_N_C_2);
muladd(n0, SECP256K1_N_C_3);
uint32_t m3; extract(m3);
extract(m3);
sumadd(l[4]);
muladd(n4, SECP256K1_N_C_0);
muladd(n3, SECP256K1_N_C_1);
muladd(n2, SECP256K1_N_C_2);
muladd(n1, SECP256K1_N_C_3);
sumadd(n0);
uint32_t m4; extract(m4);
extract(m4);
sumadd(l[5]);
muladd(n5, SECP256K1_N_C_0);
muladd(n4, SECP256K1_N_C_1);
muladd(n3, SECP256K1_N_C_2);
muladd(n2, SECP256K1_N_C_3);
sumadd(n1);
uint32_t m5; extract(m5);
extract(m5);
sumadd(l[6]);
muladd(n6, SECP256K1_N_C_0);
muladd(n5, SECP256K1_N_C_1);
muladd(n4, SECP256K1_N_C_2);
muladd(n3, SECP256K1_N_C_3);
sumadd(n2);
uint32_t m6; extract(m6);
extract(m6);
sumadd(l[7]);
muladd(n7, SECP256K1_N_C_0);
muladd(n6, SECP256K1_N_C_1);
muladd(n5, SECP256K1_N_C_2);
muladd(n4, SECP256K1_N_C_3);
sumadd(n3);
uint32_t m7; extract(m7);
extract(m7);
muladd(n7, SECP256K1_N_C_1);
muladd(n6, SECP256K1_N_C_2);
muladd(n5, SECP256K1_N_C_3);
sumadd(n4);
uint32_t m8; extract(m8);
extract(m8);
muladd(n7, SECP256K1_N_C_2);
muladd(n6, SECP256K1_N_C_3);
sumadd(n5);
uint32_t m9; extract(m9);
extract(m9);
muladd(n7, SECP256K1_N_C_3);
sumadd(n6);
uint32_t m10; extract(m10);
extract(m10);
sumadd_fast(n7);
uint32_t m11; extract_fast(m11);
extract_fast(m11);
VERIFY_CHECK(c0 <= 1);
uint32_t m12 = c0;
m12 = c0;
/* Reduce 385 bits into 258. */
/* p[0..8] = m[0..7] + m[8..12] * SECP256K1_N_C. */
c0 = m0; c1 = 0; c2 = 0;
muladd_fast(m8, SECP256K1_N_C_0);
uint32_t p0; extract_fast(p0);
extract_fast(p0);
sumadd_fast(m1);
muladd(m9, SECP256K1_N_C_0);
muladd(m8, SECP256K1_N_C_1);
uint32_t p1; extract(p1);
extract(p1);
sumadd(m2);
muladd(m10, SECP256K1_N_C_0);
muladd(m9, SECP256K1_N_C_1);
muladd(m8, SECP256K1_N_C_2);
uint32_t p2; extract(p2);
extract(p2);
sumadd(m3);
muladd(m11, SECP256K1_N_C_0);
muladd(m10, SECP256K1_N_C_1);
muladd(m9, SECP256K1_N_C_2);
muladd(m8, SECP256K1_N_C_3);
uint32_t p3; extract(p3);
extract(p3);
sumadd(m4);
muladd(m12, SECP256K1_N_C_0);
muladd(m11, SECP256K1_N_C_1);
muladd(m10, SECP256K1_N_C_2);
muladd(m9, SECP256K1_N_C_3);
sumadd(m8);
uint32_t p4; extract(p4);
extract(p4);
sumadd(m5);
muladd(m12, SECP256K1_N_C_1);
muladd(m11, SECP256K1_N_C_2);
muladd(m10, SECP256K1_N_C_3);
sumadd(m9);
uint32_t p5; extract(p5);
extract(p5);
sumadd(m6);
muladd(m12, SECP256K1_N_C_2);
muladd(m11, SECP256K1_N_C_3);
sumadd(m10);
uint32_t p6; extract(p6);
extract(p6);
sumadd_fast(m7);
muladd_fast(m12, SECP256K1_N_C_3);
sumadd_fast(m11);
uint32_t p7; extract_fast(p7);
uint32_t p8 = c0 + m12;
extract_fast(p7);
p8 = c0 + m12;
VERIFY_CHECK(p8 <= 2);
/* Reduce 258 bits into 256. */
/* r[0..7] = p[0..7] + p[8] * SECP256K1_N_C. */
uint64_t c = p0 + (uint64_t)SECP256K1_N_C_0 * p8;
c = p0 + (uint64_t)SECP256K1_N_C_0 * p8;
r->d[0] = c & 0xFFFFFFFFUL; c >>= 32;
c += p1 + (uint64_t)SECP256K1_N_C_1 * p8;
r->d[1] = c & 0xFFFFFFFFUL; c >>= 32;
@@ -454,7 +462,7 @@ static void secp256k1_scalar_reduce_512(secp256k1_scalar_t *r, const uint32_t *l
secp256k1_scalar_reduce(r, c + secp256k1_scalar_check_overflow(r));
}
static void secp256k1_scalar_mul_512(uint32_t l[16], const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
static void secp256k1_scalar_mul_512(uint32_t *l, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
/* 96 bit accumulator. */
uint32_t c0 = 0, c1 = 0, c2 = 0;
@@ -542,7 +550,7 @@ static void secp256k1_scalar_mul_512(uint32_t l[16], const secp256k1_scalar_t *a
l[15] = c0;
}
static void secp256k1_scalar_sqr_512(uint32_t l[16], const secp256k1_scalar_t *a) {
static void secp256k1_scalar_sqr_512(uint32_t *l, const secp256k1_scalar_t *a) {
/* 96 bit accumulator. */
uint32_t c0 = 0, c1 = 0, c2 = 0;
@@ -622,6 +630,7 @@ static void secp256k1_scalar_sqr(secp256k1_scalar_t *r, const secp256k1_scalar_t
secp256k1_scalar_reduce_512(r, l);
}
#ifdef USE_ENDOMORPHISM
static void secp256k1_scalar_split_128(secp256k1_scalar_t *r1, secp256k1_scalar_t *r2, const secp256k1_scalar_t *a) {
r1->d[0] = a->d[0];
r1->d[1] = a->d[1];
@@ -640,18 +649,22 @@ static void secp256k1_scalar_split_128(secp256k1_scalar_t *r1, secp256k1_scalar_
r2->d[6] = 0;
r2->d[7] = 0;
}
#endif
SECP256K1_INLINE static int secp256k1_scalar_eq(const secp256k1_scalar_t *a, const secp256k1_scalar_t *b) {
return ((a->d[0] ^ b->d[0]) | (a->d[1] ^ b->d[1]) | (a->d[2] ^ b->d[2]) | (a->d[3] ^ b->d[3]) | (a->d[4] ^ b->d[4]) | (a->d[5] ^ b->d[5]) | (a->d[6] ^ b->d[6]) | (a->d[7] ^ b->d[7])) == 0;
}
SECP256K1_INLINE static void secp256k1_scalar_mul_shift_var(secp256k1_scalar_t *r, const secp256k1_scalar_t *a, const secp256k1_scalar_t *b, unsigned int shift) {
VERIFY_CHECK(shift >= 256);
uint32_t l[16];
unsigned int shiftlimbs;
unsigned int shiftlow;
unsigned int shifthigh;
VERIFY_CHECK(shift >= 256);
secp256k1_scalar_mul_512(l, a, b);
unsigned int shiftlimbs = shift >> 5;
unsigned int shiftlow = shift & 0x1F;
unsigned int shifthigh = 32 - shiftlow;
shiftlimbs = shift >> 5;
shiftlow = shift & 0x1F;
shifthigh = 32 - shiftlow;
r->d[0] = shift < 512 ? (l[0 + shiftlimbs] >> shiftlow | (shift < 480 && shiftlow ? (l[1 + shiftlimbs] << shifthigh) : 0)) : 0;
r->d[1] = shift < 480 ? (l[1 + shiftlimbs] >> shiftlow | (shift < 448 && shiftlow ? (l[2 + shiftlimbs] << shifthigh) : 0)) : 0;
r->d[2] = shift < 448 ? (l[2 + shiftlimbs] >> shiftlow | (shift < 416 && shiftlow ? (l[3 + shiftlimbs] << shifthigh) : 0)) : 0;