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ed25519-ref10.c
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ed25519-ref10.c
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#include <stdint.h>
#include <stddef.h>
#include <string.h>
static int crypto_verify_32(const unsigned char *x,const unsigned char *y)
{
unsigned int differentbits = 0;
#define F(i) differentbits |= x[i] ^ y[i];
F(0)
F(1)
F(2)
F(3)
F(4)
F(5)
F(6)
F(7)
F(8)
F(9)
F(10)
F(11)
F(12)
F(13)
F(14)
F(15)
F(16)
F(17)
F(18)
F(19)
F(20)
F(21)
F(22)
F(23)
F(24)
F(25)
F(26)
F(27)
F(28)
F(29)
F(30)
F(31)
return (1 & ((differentbits - 1) >> 8)) - 1;
}
#if defined(ED25519_REFHASH)
/* reference/slow SHA-512. really, do not use this */
#define HASH_BLOCK_SIZE 128
#define HASH_DIGEST_SIZE 64
typedef struct sha512_state_t {
uint64_t H[8];
uint64_t T[2];
uint32_t leftover;
uint8_t buffer[HASH_BLOCK_SIZE];
} sha512_state;
typedef sha512_state ed25519_hash_context;
static const uint64_t sha512_constants[80] = {
0x428a2f98d728ae22ull, 0x7137449123ef65cdull, 0xb5c0fbcfec4d3b2full, 0xe9b5dba58189dbbcull,
0x3956c25bf348b538ull, 0x59f111f1b605d019ull, 0x923f82a4af194f9bull, 0xab1c5ed5da6d8118ull,
0xd807aa98a3030242ull, 0x12835b0145706fbeull, 0x243185be4ee4b28cull, 0x550c7dc3d5ffb4e2ull,
0x72be5d74f27b896full, 0x80deb1fe3b1696b1ull, 0x9bdc06a725c71235ull, 0xc19bf174cf692694ull,
0xe49b69c19ef14ad2ull, 0xefbe4786384f25e3ull, 0x0fc19dc68b8cd5b5ull, 0x240ca1cc77ac9c65ull,
0x2de92c6f592b0275ull, 0x4a7484aa6ea6e483ull, 0x5cb0a9dcbd41fbd4ull, 0x76f988da831153b5ull,
0x983e5152ee66dfabull, 0xa831c66d2db43210ull, 0xb00327c898fb213full, 0xbf597fc7beef0ee4ull,
0xc6e00bf33da88fc2ull, 0xd5a79147930aa725ull, 0x06ca6351e003826full, 0x142929670a0e6e70ull,
0x27b70a8546d22ffcull, 0x2e1b21385c26c926ull, 0x4d2c6dfc5ac42aedull, 0x53380d139d95b3dfull,
0x650a73548baf63deull, 0x766a0abb3c77b2a8ull, 0x81c2c92e47edaee6ull, 0x92722c851482353bull,
0xa2bfe8a14cf10364ull, 0xa81a664bbc423001ull, 0xc24b8b70d0f89791ull, 0xc76c51a30654be30ull,
0xd192e819d6ef5218ull, 0xd69906245565a910ull, 0xf40e35855771202aull, 0x106aa07032bbd1b8ull,
0x19a4c116b8d2d0c8ull, 0x1e376c085141ab53ull, 0x2748774cdf8eeb99ull, 0x34b0bcb5e19b48a8ull,
0x391c0cb3c5c95a63ull, 0x4ed8aa4ae3418acbull, 0x5b9cca4f7763e373ull, 0x682e6ff3d6b2b8a3ull,
0x748f82ee5defb2fcull, 0x78a5636f43172f60ull, 0x84c87814a1f0ab72ull, 0x8cc702081a6439ecull,
0x90befffa23631e28ull, 0xa4506cebde82bde9ull, 0xbef9a3f7b2c67915ull, 0xc67178f2e372532bull,
0xca273eceea26619cull, 0xd186b8c721c0c207ull, 0xeada7dd6cde0eb1eull, 0xf57d4f7fee6ed178ull,
0x06f067aa72176fbaull, 0x0a637dc5a2c898a6ull, 0x113f9804bef90daeull, 0x1b710b35131c471bull,
0x28db77f523047d84ull, 0x32caab7b40c72493ull, 0x3c9ebe0a15c9bebcull, 0x431d67c49c100d4cull,
0x4cc5d4becb3e42b6ull, 0x597f299cfc657e2aull, 0x5fcb6fab3ad6faecull, 0x6c44198c4a475817ull
};
static uint64_t
sha512_ROTR64(uint64_t x, int k) {
return (x >> k) | (x << (64 - k));
}
static uint64_t
sha512_LOAD64_BE(const uint8_t *p) {
return
((uint64_t)p[0] << 56) |
((uint64_t)p[1] << 48) |
((uint64_t)p[2] << 40) |
((uint64_t)p[3] << 32) |
((uint64_t)p[4] << 24) |
((uint64_t)p[5] << 16) |
((uint64_t)p[6] << 8) |
((uint64_t)p[7] );
}
static void
sha512_STORE64_BE(uint8_t *p, uint64_t v) {
p[0] = (uint8_t)(v >> 56);
p[1] = (uint8_t)(v >> 48);
p[2] = (uint8_t)(v >> 40);
p[3] = (uint8_t)(v >> 32);
p[4] = (uint8_t)(v >> 24);
p[5] = (uint8_t)(v >> 16);
p[6] = (uint8_t)(v >> 8);
p[7] = (uint8_t)(v );
}
#define Ch(x,y,z) (z ^ (x & (y ^ z)))
#define Maj(x,y,z) (((x | y) & z) | (x & y))
#define S0(x) (sha512_ROTR64(x, 28) ^ sha512_ROTR64(x, 34) ^ sha512_ROTR64(x, 39))
#define S1(x) (sha512_ROTR64(x, 14) ^ sha512_ROTR64(x, 18) ^ sha512_ROTR64(x, 41))
#define G0(x) (sha512_ROTR64(x, 1) ^ sha512_ROTR64(x, 8) ^ (x >> 7))
#define G1(x) (sha512_ROTR64(x, 19) ^ sha512_ROTR64(x, 61) ^ (x >> 6))
#define W0(in,i) (sha512_LOAD64_BE(&in[i * 8]))
#define W1(i) (G1(w[i - 2]) + w[i - 7] + G0(w[i - 15]) + w[i - 16])
#define STEP(i) \
t1 = S0(r[0]) + Maj(r[0], r[1], r[2]); \
t0 = r[7] + S1(r[4]) + Ch(r[4], r[5], r[6]) + sha512_constants[i] + w[i]; \
r[7] = r[6]; \
r[6] = r[5]; \
r[5] = r[4]; \
r[4] = r[3] + t0; \
r[3] = r[2]; \
r[2] = r[1]; \
r[1] = r[0]; \
r[0] = t0 + t1;
static void
sha512_blocks(sha512_state *S, const uint8_t *in, size_t blocks) {
uint64_t r[8], w[80], t0, t1;
size_t i;
for (i = 0; i < 8; i++) r[i] = S->H[i];
while (blocks--) {
for (i = 0; i < 16; i++) { w[i] = W0(in, i); }
for (i = 16; i < 80; i++) { w[i] = W1(i); }
for (i = 0; i < 80; i++) { STEP(i); }
for (i = 0; i < 8; i++) { r[i] += S->H[i]; S->H[i] = r[i]; }
S->T[0] += HASH_BLOCK_SIZE * 8;
S->T[1] += (!S->T[0]) ? 1 : 0;
in += HASH_BLOCK_SIZE;
}
}
static void
ed25519_hash_init(sha512_state *S) {
S->H[0] = 0x6a09e667f3bcc908ull;
S->H[1] = 0xbb67ae8584caa73bull;
S->H[2] = 0x3c6ef372fe94f82bull;
S->H[3] = 0xa54ff53a5f1d36f1ull;
S->H[4] = 0x510e527fade682d1ull;
S->H[5] = 0x9b05688c2b3e6c1full;
S->H[6] = 0x1f83d9abfb41bd6bull;
S->H[7] = 0x5be0cd19137e2179ull;
S->T[0] = 0;
S->T[1] = 0;
S->leftover = 0;
}
static void
ed25519_hash_update(sha512_state *S, const uint8_t *in, size_t inlen) {
size_t blocks, want;
/* handle the previous data */
if (S->leftover) {
want = (HASH_BLOCK_SIZE - S->leftover);
want = (want < inlen) ? want : inlen;
memcpy(S->buffer + S->leftover, in, want);
S->leftover += (uint32_t)want;
if (S->leftover < HASH_BLOCK_SIZE)
return;
in += want;
inlen -= want;
sha512_blocks(S, S->buffer, 1);
}
/* handle the current data */
blocks = (inlen & ~(HASH_BLOCK_SIZE - 1));
S->leftover = (uint32_t)(inlen - blocks);
if (blocks) {
sha512_blocks(S, in, blocks / HASH_BLOCK_SIZE);
in += blocks;
}
/* handle leftover data */
if (S->leftover)
memcpy(S->buffer, in, S->leftover);
}
static void
ed25519_hash_final(sha512_state *S, uint8_t *hash) {
uint64_t t0 = S->T[0] + (S->leftover * 8), t1 = S->T[1];
S->buffer[S->leftover] = 0x80;
if (S->leftover <= 111) {
memset(S->buffer + S->leftover + 1, 0, 111 - S->leftover);
} else {
memset(S->buffer + S->leftover + 1, 0, 127 - S->leftover);
sha512_blocks(S, S->buffer, 1);
memset(S->buffer, 0, 112);
}
sha512_STORE64_BE(S->buffer + 112, t1);
sha512_STORE64_BE(S->buffer + 120, t0);
sha512_blocks(S, S->buffer, 1);
sha512_STORE64_BE(&hash[ 0], S->H[0]);
sha512_STORE64_BE(&hash[ 8], S->H[1]);
sha512_STORE64_BE(&hash[16], S->H[2]);
sha512_STORE64_BE(&hash[24], S->H[3]);
sha512_STORE64_BE(&hash[32], S->H[4]);
sha512_STORE64_BE(&hash[40], S->H[5]);
sha512_STORE64_BE(&hash[48], S->H[6]);
sha512_STORE64_BE(&hash[56], S->H[7]);
}
static void
crypto_hash_sha512(unsigned char *hash, const unsigned char *in, size_t inlen) {
ed25519_hash_context ctx;
ed25519_hash_init(&ctx);
ed25519_hash_update(&ctx, in, inlen);
ed25519_hash_final(&ctx, hash);
}
#else
#include <openssl/sha.h>
static void
crypto_hash_sha512(unsigned char *hash, const unsigned char *in, size_t inlen) {
SHA512(in, inlen, hash);
}
#endif
typedef int32_t crypto_int32;
typedef uint32_t crypto_uint32;
typedef int64_t crypto_int64;
typedef uint64_t crypto_uint64;
typedef crypto_int32 fe[10];
/*
h = 0
*/
static void fe_0(fe h)
{
h[0] = 0;
h[1] = 0;
h[2] = 0;
h[3] = 0;
h[4] = 0;
h[5] = 0;
h[6] = 0;
h[7] = 0;
h[8] = 0;
h[9] = 0;
}
/*
h = 1
*/
static void fe_1(fe h)
{
h[0] = 1;
h[1] = 0;
h[2] = 0;
h[3] = 0;
h[4] = 0;
h[5] = 0;
h[6] = 0;
h[7] = 0;
h[8] = 0;
h[9] = 0;
}
/*
h = f + g
Can overlap h with f or g.
Preconditions:
|f| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
|g| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
Postconditions:
|h| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
*/
static void fe_add(fe h,const fe f,const fe g)
{
crypto_int32 f0 = f[0];
crypto_int32 f1 = f[1];
crypto_int32 f2 = f[2];
crypto_int32 f3 = f[3];
crypto_int32 f4 = f[4];
crypto_int32 f5 = f[5];
crypto_int32 f6 = f[6];
crypto_int32 f7 = f[7];
crypto_int32 f8 = f[8];
crypto_int32 f9 = f[9];
crypto_int32 g0 = g[0];
crypto_int32 g1 = g[1];
crypto_int32 g2 = g[2];
crypto_int32 g3 = g[3];
crypto_int32 g4 = g[4];
crypto_int32 g5 = g[5];
crypto_int32 g6 = g[6];
crypto_int32 g7 = g[7];
crypto_int32 g8 = g[8];
crypto_int32 g9 = g[9];
crypto_int32 h0 = f0 + g0;
crypto_int32 h1 = f1 + g1;
crypto_int32 h2 = f2 + g2;
crypto_int32 h3 = f3 + g3;
crypto_int32 h4 = f4 + g4;
crypto_int32 h5 = f5 + g5;
crypto_int32 h6 = f6 + g6;
crypto_int32 h7 = f7 + g7;
crypto_int32 h8 = f8 + g8;
crypto_int32 h9 = f9 + g9;
h[0] = h0;
h[1] = h1;
h[2] = h2;
h[3] = h3;
h[4] = h4;
h[5] = h5;
h[6] = h6;
h[7] = h7;
h[8] = h8;
h[9] = h9;
}
/*
Replace (f,g) with (g,g) if b == 1;
replace (f,g) with (f,g) if b == 0.
Preconditions: b in {0,1}.
*/
static void fe_cmov(fe f,const fe g,unsigned int b)
{
crypto_int32 f0 = f[0];
crypto_int32 f1 = f[1];
crypto_int32 f2 = f[2];
crypto_int32 f3 = f[3];
crypto_int32 f4 = f[4];
crypto_int32 f5 = f[5];
crypto_int32 f6 = f[6];
crypto_int32 f7 = f[7];
crypto_int32 f8 = f[8];
crypto_int32 f9 = f[9];
crypto_int32 g0 = g[0];
crypto_int32 g1 = g[1];
crypto_int32 g2 = g[2];
crypto_int32 g3 = g[3];
crypto_int32 g4 = g[4];
crypto_int32 g5 = g[5];
crypto_int32 g6 = g[6];
crypto_int32 g7 = g[7];
crypto_int32 g8 = g[8];
crypto_int32 g9 = g[9];
crypto_int32 x0 = f0 ^ g0;
crypto_int32 x1 = f1 ^ g1;
crypto_int32 x2 = f2 ^ g2;
crypto_int32 x3 = f3 ^ g3;
crypto_int32 x4 = f4 ^ g4;
crypto_int32 x5 = f5 ^ g5;
crypto_int32 x6 = f6 ^ g6;
crypto_int32 x7 = f7 ^ g7;
crypto_int32 x8 = f8 ^ g8;
crypto_int32 x9 = f9 ^ g9;
b = -b;
x0 &= b;
x1 &= b;
x2 &= b;
x3 &= b;
x4 &= b;
x5 &= b;
x6 &= b;
x7 &= b;
x8 &= b;
x9 &= b;
f[0] = f0 ^ x0;
f[1] = f1 ^ x1;
f[2] = f2 ^ x2;
f[3] = f3 ^ x3;
f[4] = f4 ^ x4;
f[5] = f5 ^ x5;
f[6] = f6 ^ x6;
f[7] = f7 ^ x7;
f[8] = f8 ^ x8;
f[9] = f9 ^ x9;
}
/*
h = f
*/
static void fe_copy(fe h,const fe f)
{
crypto_int32 f0 = f[0];
crypto_int32 f1 = f[1];
crypto_int32 f2 = f[2];
crypto_int32 f3 = f[3];
crypto_int32 f4 = f[4];
crypto_int32 f5 = f[5];
crypto_int32 f6 = f[6];
crypto_int32 f7 = f[7];
crypto_int32 f8 = f[8];
crypto_int32 f9 = f[9];
h[0] = f0;
h[1] = f1;
h[2] = f2;
h[3] = f3;
h[4] = f4;
h[5] = f5;
h[6] = f6;
h[7] = f7;
h[8] = f8;
h[9] = f9;
}
static crypto_uint64 load_3(const unsigned char *in)
{
crypto_uint64 result;
result = (crypto_uint64) in[0];
result |= ((crypto_uint64) in[1]) << 8;
result |= ((crypto_uint64) in[2]) << 16;
return result;
}
static crypto_uint64 load_4(const unsigned char *in)
{
crypto_uint64 result;
result = (crypto_uint64) in[0];
result |= ((crypto_uint64) in[1]) << 8;
result |= ((crypto_uint64) in[2]) << 16;
result |= ((crypto_uint64) in[3]) << 24;
return result;
}
/*
Ignores top bit of h.
*/
static void fe_frombytes(fe h,const unsigned char *s)
{
crypto_int64 h0 = load_4(s);
crypto_int64 h1 = load_3(s + 4) << 6;
crypto_int64 h2 = load_3(s + 7) << 5;
crypto_int64 h3 = load_3(s + 10) << 3;
crypto_int64 h4 = load_3(s + 13) << 2;
crypto_int64 h5 = load_4(s + 16);
crypto_int64 h6 = load_3(s + 20) << 7;
crypto_int64 h7 = load_3(s + 23) << 5;
crypto_int64 h8 = load_3(s + 26) << 4;
crypto_int64 h9 = (load_3(s + 29) & 8388607) << 2;
crypto_int64 carry0;
crypto_int64 carry1;
crypto_int64 carry2;
crypto_int64 carry3;
crypto_int64 carry4;
crypto_int64 carry5;
crypto_int64 carry6;
crypto_int64 carry7;
crypto_int64 carry8;
crypto_int64 carry9;
carry9 = (h9 + (crypto_int64) (1<<24)) >> 25; h0 += carry9 * 19; h9 -= carry9 << 25;
carry1 = (h1 + (crypto_int64) (1<<24)) >> 25; h2 += carry1; h1 -= carry1 << 25;
carry3 = (h3 + (crypto_int64) (1<<24)) >> 25; h4 += carry3; h3 -= carry3 << 25;
carry5 = (h5 + (crypto_int64) (1<<24)) >> 25; h6 += carry5; h5 -= carry5 << 25;
carry7 = (h7 + (crypto_int64) (1<<24)) >> 25; h8 += carry7; h7 -= carry7 << 25;
carry0 = (h0 + (crypto_int64) (1<<25)) >> 26; h1 += carry0; h0 -= carry0 << 26;
carry2 = (h2 + (crypto_int64) (1<<25)) >> 26; h3 += carry2; h2 -= carry2 << 26;
carry4 = (h4 + (crypto_int64) (1<<25)) >> 26; h5 += carry4; h4 -= carry4 << 26;
carry6 = (h6 + (crypto_int64) (1<<25)) >> 26; h7 += carry6; h6 -= carry6 << 26;
carry8 = (h8 + (crypto_int64) (1<<25)) >> 26; h9 += carry8; h8 -= carry8 << 26;
h[0] = h0;
h[1] = h1;
h[2] = h2;
h[3] = h3;
h[4] = h4;
h[5] = h5;
h[6] = h6;
h[7] = h7;
h[8] = h8;
h[9] = h9;
}
/*
Preconditions:
|h| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
Write p=2^255-19; q=floor(h/p).
Basic claim: q = floor(2^(-255)(h + 19 2^(-25)h9 + 2^(-1))).
Proof:
Have |h|<=p so |q|<=1 so |19^2 2^(-255) q|<1/4.
Also have |h-2^230 h9|<2^231 so |19 2^(-255)(h-2^230 h9)|<1/4.
Write y=2^(-1)-19^2 2^(-255)q-19 2^(-255)(h-2^230 h9).
Then 0<y<1.
Write r=h-pq.
Have 0<=r<=p-1=2^255-20.
Thus 0<=r+19(2^-255)r<r+19(2^-255)2^255<=2^255-1.
Write x=r+19(2^-255)r+y.
Then 0<x<2^255 so floor(2^(-255)x) = 0 so floor(q+2^(-255)x) = q.
Have q+2^(-255)x = 2^(-255)(h + 19 2^(-25) h9 + 2^(-1))
so floor(2^(-255)(h + 19 2^(-25) h9 + 2^(-1))) = q.
*/
static void fe_tobytes(unsigned char *s,const fe h)
{
crypto_int32 h0 = h[0];
crypto_int32 h1 = h[1];
crypto_int32 h2 = h[2];
crypto_int32 h3 = h[3];
crypto_int32 h4 = h[4];
crypto_int32 h5 = h[5];
crypto_int32 h6 = h[6];
crypto_int32 h7 = h[7];
crypto_int32 h8 = h[8];
crypto_int32 h9 = h[9];
crypto_int32 q;
crypto_int32 carry0;
crypto_int32 carry1;
crypto_int32 carry2;
crypto_int32 carry3;
crypto_int32 carry4;
crypto_int32 carry5;
crypto_int32 carry6;
crypto_int32 carry7;
crypto_int32 carry8;
crypto_int32 carry9;
q = (19 * h9 + (((crypto_int32) 1) << 24)) >> 25;
q = (h0 + q) >> 26;
q = (h1 + q) >> 25;
q = (h2 + q) >> 26;
q = (h3 + q) >> 25;
q = (h4 + q) >> 26;
q = (h5 + q) >> 25;
q = (h6 + q) >> 26;
q = (h7 + q) >> 25;
q = (h8 + q) >> 26;
q = (h9 + q) >> 25;
/* Goal: Output h-(2^255-19)q, which is between 0 and 2^255-20. */
h0 += 19 * q;
/* Goal: Output h-2^255 q, which is between 0 and 2^255-20. */
carry0 = h0 >> 26; h1 += carry0; h0 -= carry0 << 26;
carry1 = h1 >> 25; h2 += carry1; h1 -= carry1 << 25;
carry2 = h2 >> 26; h3 += carry2; h2 -= carry2 << 26;
carry3 = h3 >> 25; h4 += carry3; h3 -= carry3 << 25;
carry4 = h4 >> 26; h5 += carry4; h4 -= carry4 << 26;
carry5 = h5 >> 25; h6 += carry5; h5 -= carry5 << 25;
carry6 = h6 >> 26; h7 += carry6; h6 -= carry6 << 26;
carry7 = h7 >> 25; h8 += carry7; h7 -= carry7 << 25;
carry8 = h8 >> 26; h9 += carry8; h8 -= carry8 << 26;
carry9 = h9 >> 25; h9 -= carry9 << 25;
/* h10 = carry9 */
/*
Goal: Output h0+...+2^255 h10-2^255 q, which is between 0 and 2^255-20.
Have h0+...+2^230 h9 between 0 and 2^255-1;
evidently 2^255 h10-2^255 q = 0.
Goal: Output h0+...+2^230 h9.
*/
s[0] = h0 >> 0;
s[1] = h0 >> 8;
s[2] = h0 >> 16;
s[3] = (h0 >> 24) | (h1 << 2);
s[4] = h1 >> 6;
s[5] = h1 >> 14;
s[6] = (h1 >> 22) | (h2 << 3);
s[7] = h2 >> 5;
s[8] = h2 >> 13;
s[9] = (h2 >> 21) | (h3 << 5);
s[10] = h3 >> 3;
s[11] = h3 >> 11;
s[12] = (h3 >> 19) | (h4 << 6);
s[13] = h4 >> 2;
s[14] = h4 >> 10;
s[15] = h4 >> 18;
s[16] = h5 >> 0;
s[17] = h5 >> 8;
s[18] = h5 >> 16;
s[19] = (h5 >> 24) | (h6 << 1);
s[20] = h6 >> 7;
s[21] = h6 >> 15;
s[22] = (h6 >> 23) | (h7 << 3);
s[23] = h7 >> 5;
s[24] = h7 >> 13;
s[25] = (h7 >> 21) | (h8 << 4);
s[26] = h8 >> 4;
s[27] = h8 >> 12;
s[28] = (h8 >> 20) | (h9 << 6);
s[29] = h9 >> 2;
s[30] = h9 >> 10;
s[31] = h9 >> 18;
}
/*
h = f - g
Can overlap h with f or g.
Preconditions:
|f| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
|g| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
Postconditions:
|h| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
*/
static void fe_sub(fe h,const fe f,const fe g)
{
crypto_int32 f0 = f[0];
crypto_int32 f1 = f[1];
crypto_int32 f2 = f[2];
crypto_int32 f3 = f[3];
crypto_int32 f4 = f[4];
crypto_int32 f5 = f[5];
crypto_int32 f6 = f[6];
crypto_int32 f7 = f[7];
crypto_int32 f8 = f[8];
crypto_int32 f9 = f[9];
crypto_int32 g0 = g[0];
crypto_int32 g1 = g[1];
crypto_int32 g2 = g[2];
crypto_int32 g3 = g[3];
crypto_int32 g4 = g[4];
crypto_int32 g5 = g[5];
crypto_int32 g6 = g[6];
crypto_int32 g7 = g[7];
crypto_int32 g8 = g[8];
crypto_int32 g9 = g[9];
crypto_int32 h0 = f0 - g0;
crypto_int32 h1 = f1 - g1;
crypto_int32 h2 = f2 - g2;
crypto_int32 h3 = f3 - g3;
crypto_int32 h4 = f4 - g4;
crypto_int32 h5 = f5 - g5;
crypto_int32 h6 = f6 - g6;
crypto_int32 h7 = f7 - g7;
crypto_int32 h8 = f8 - g8;
crypto_int32 h9 = f9 - g9;
h[0] = h0;
h[1] = h1;
h[2] = h2;
h[3] = h3;
h[4] = h4;
h[5] = h5;
h[6] = h6;
h[7] = h7;
h[8] = h8;
h[9] = h9;
}
/*
h = f * f
Can overlap h with f.
Preconditions:
|f| bounded by 1.65*2^26,1.65*2^25,1.65*2^26,1.65*2^25,etc.
Postconditions:
|h| bounded by 1.01*2^25,1.01*2^24,1.01*2^25,1.01*2^24,etc.
*/
/*
See fe_mul.c for discussion of implementation strategy.
*/
static void fe_sq(fe h,const fe f)
{
crypto_int32 f0 = f[0];
crypto_int32 f1 = f[1];
crypto_int32 f2 = f[2];
crypto_int32 f3 = f[3];
crypto_int32 f4 = f[4];
crypto_int32 f5 = f[5];
crypto_int32 f6 = f[6];
crypto_int32 f7 = f[7];
crypto_int32 f8 = f[8];
crypto_int32 f9 = f[9];
crypto_int32 f0_2 = 2 * f0;
crypto_int32 f1_2 = 2 * f1;
crypto_int32 f2_2 = 2 * f2;
crypto_int32 f3_2 = 2 * f3;
crypto_int32 f4_2 = 2 * f4;
crypto_int32 f5_2 = 2 * f5;
crypto_int32 f6_2 = 2 * f6;
crypto_int32 f7_2 = 2 * f7;
crypto_int32 f5_38 = 38 * f5; /* 1.959375*2^30 */
crypto_int32 f6_19 = 19 * f6; /* 1.959375*2^30 */
crypto_int32 f7_38 = 38 * f7; /* 1.959375*2^30 */
crypto_int32 f8_19 = 19 * f8; /* 1.959375*2^30 */
crypto_int32 f9_38 = 38 * f9; /* 1.959375*2^30 */
crypto_int64 f0f0 = f0 * (crypto_int64) f0;
crypto_int64 f0f1_2 = f0_2 * (crypto_int64) f1;
crypto_int64 f0f2_2 = f0_2 * (crypto_int64) f2;
crypto_int64 f0f3_2 = f0_2 * (crypto_int64) f3;
crypto_int64 f0f4_2 = f0_2 * (crypto_int64) f4;
crypto_int64 f0f5_2 = f0_2 * (crypto_int64) f5;
crypto_int64 f0f6_2 = f0_2 * (crypto_int64) f6;
crypto_int64 f0f7_2 = f0_2 * (crypto_int64) f7;
crypto_int64 f0f8_2 = f0_2 * (crypto_int64) f8;
crypto_int64 f0f9_2 = f0_2 * (crypto_int64) f9;
crypto_int64 f1f1_2 = f1_2 * (crypto_int64) f1;
crypto_int64 f1f2_2 = f1_2 * (crypto_int64) f2;
crypto_int64 f1f3_4 = f1_2 * (crypto_int64) f3_2;
crypto_int64 f1f4_2 = f1_2 * (crypto_int64) f4;
crypto_int64 f1f5_4 = f1_2 * (crypto_int64) f5_2;
crypto_int64 f1f6_2 = f1_2 * (crypto_int64) f6;
crypto_int64 f1f7_4 = f1_2 * (crypto_int64) f7_2;
crypto_int64 f1f8_2 = f1_2 * (crypto_int64) f8;
crypto_int64 f1f9_76 = f1_2 * (crypto_int64) f9_38;
crypto_int64 f2f2 = f2 * (crypto_int64) f2;
crypto_int64 f2f3_2 = f2_2 * (crypto_int64) f3;
crypto_int64 f2f4_2 = f2_2 * (crypto_int64) f4;
crypto_int64 f2f5_2 = f2_2 * (crypto_int64) f5;
crypto_int64 f2f6_2 = f2_2 * (crypto_int64) f6;
crypto_int64 f2f7_2 = f2_2 * (crypto_int64) f7;
crypto_int64 f2f8_38 = f2_2 * (crypto_int64) f8_19;
crypto_int64 f2f9_38 = f2 * (crypto_int64) f9_38;
crypto_int64 f3f3_2 = f3_2 * (crypto_int64) f3;
crypto_int64 f3f4_2 = f3_2 * (crypto_int64) f4;
crypto_int64 f3f5_4 = f3_2 * (crypto_int64) f5_2;
crypto_int64 f3f6_2 = f3_2 * (crypto_int64) f6;
crypto_int64 f3f7_76 = f3_2 * (crypto_int64) f7_38;
crypto_int64 f3f8_38 = f3_2 * (crypto_int64) f8_19;
crypto_int64 f3f9_76 = f3_2 * (crypto_int64) f9_38;
crypto_int64 f4f4 = f4 * (crypto_int64) f4;
crypto_int64 f4f5_2 = f4_2 * (crypto_int64) f5;
crypto_int64 f4f6_38 = f4_2 * (crypto_int64) f6_19;
crypto_int64 f4f7_38 = f4 * (crypto_int64) f7_38;
crypto_int64 f4f8_38 = f4_2 * (crypto_int64) f8_19;
crypto_int64 f4f9_38 = f4 * (crypto_int64) f9_38;
crypto_int64 f5f5_38 = f5 * (crypto_int64) f5_38;
crypto_int64 f5f6_38 = f5_2 * (crypto_int64) f6_19;
crypto_int64 f5f7_76 = f5_2 * (crypto_int64) f7_38;
crypto_int64 f5f8_38 = f5_2 * (crypto_int64) f8_19;
crypto_int64 f5f9_76 = f5_2 * (crypto_int64) f9_38;
crypto_int64 f6f6_19 = f6 * (crypto_int64) f6_19;
crypto_int64 f6f7_38 = f6 * (crypto_int64) f7_38;
crypto_int64 f6f8_38 = f6_2 * (crypto_int64) f8_19;
crypto_int64 f6f9_38 = f6 * (crypto_int64) f9_38;
crypto_int64 f7f7_38 = f7 * (crypto_int64) f7_38;
crypto_int64 f7f8_38 = f7_2 * (crypto_int64) f8_19;
crypto_int64 f7f9_76 = f7_2 * (crypto_int64) f9_38;
crypto_int64 f8f8_19 = f8 * (crypto_int64) f8_19;
crypto_int64 f8f9_38 = f8 * (crypto_int64) f9_38;
crypto_int64 f9f9_38 = f9 * (crypto_int64) f9_38;
crypto_int64 h0 = f0f0 +f1f9_76+f2f8_38+f3f7_76+f4f6_38+f5f5_38;
crypto_int64 h1 = f0f1_2+f2f9_38+f3f8_38+f4f7_38+f5f6_38;
crypto_int64 h2 = f0f2_2+f1f1_2 +f3f9_76+f4f8_38+f5f7_76+f6f6_19;
crypto_int64 h3 = f0f3_2+f1f2_2 +f4f9_38+f5f8_38+f6f7_38;
crypto_int64 h4 = f0f4_2+f1f3_4 +f2f2 +f5f9_76+f6f8_38+f7f7_38;
crypto_int64 h5 = f0f5_2+f1f4_2 +f2f3_2 +f6f9_38+f7f8_38;
crypto_int64 h6 = f0f6_2+f1f5_4 +f2f4_2 +f3f3_2 +f7f9_76+f8f8_19;
crypto_int64 h7 = f0f7_2+f1f6_2 +f2f5_2 +f3f4_2 +f8f9_38;
crypto_int64 h8 = f0f8_2+f1f7_4 +f2f6_2 +f3f5_4 +f4f4 +f9f9_38;
crypto_int64 h9 = f0f9_2+f1f8_2 +f2f7_2 +f3f6_2 +f4f5_2;
crypto_int64 carry0;
crypto_int64 carry1;
crypto_int64 carry2;
crypto_int64 carry3;
crypto_int64 carry4;
crypto_int64 carry5;
crypto_int64 carry6;
crypto_int64 carry7;
crypto_int64 carry8;
crypto_int64 carry9;
carry0 = (h0 + (crypto_int64) (1<<25)) >> 26; h1 += carry0; h0 -= carry0 << 26;
carry4 = (h4 + (crypto_int64) (1<<25)) >> 26; h5 += carry4; h4 -= carry4 << 26;
carry1 = (h1 + (crypto_int64) (1<<24)) >> 25; h2 += carry1; h1 -= carry1 << 25;
carry5 = (h5 + (crypto_int64) (1<<24)) >> 25; h6 += carry5; h5 -= carry5 << 25;
carry2 = (h2 + (crypto_int64) (1<<25)) >> 26; h3 += carry2; h2 -= carry2 << 26;
carry6 = (h6 + (crypto_int64) (1<<25)) >> 26; h7 += carry6; h6 -= carry6 << 26;
carry3 = (h3 + (crypto_int64) (1<<24)) >> 25; h4 += carry3; h3 -= carry3 << 25;
carry7 = (h7 + (crypto_int64) (1<<24)) >> 25; h8 += carry7; h7 -= carry7 << 25;
carry4 = (h4 + (crypto_int64) (1<<25)) >> 26; h5 += carry4; h4 -= carry4 << 26;
carry8 = (h8 + (crypto_int64) (1<<25)) >> 26; h9 += carry8; h8 -= carry8 << 26;
carry9 = (h9 + (crypto_int64) (1<<24)) >> 25; h0 += carry9 * 19; h9 -= carry9 << 25;
carry0 = (h0 + (crypto_int64) (1<<25)) >> 26; h1 += carry0; h0 -= carry0 << 26;
h[0] = h0;
h[1] = h1;
h[2] = h2;
h[3] = h3;
h[4] = h4;
h[5] = h5;
h[6] = h6;
h[7] = h7;
h[8] = h8;
h[9] = h9;
}
/*
h = 2 * f * f
Can overlap h with f.
Preconditions:
|f| bounded by 1.65*2^26,1.65*2^25,1.65*2^26,1.65*2^25,etc.
Postconditions:
|h| bounded by 1.01*2^25,1.01*2^24,1.01*2^25,1.01*2^24,etc.
*/
/*
See fe_mul.c for discussion of implementation strategy.
*/
static void fe_sq2(fe h,const fe f)
{
crypto_int32 f0 = f[0];
crypto_int32 f1 = f[1];
crypto_int32 f2 = f[2];
crypto_int32 f3 = f[3];
crypto_int32 f4 = f[4];
crypto_int32 f5 = f[5];
crypto_int32 f6 = f[6];
crypto_int32 f7 = f[7];
crypto_int32 f8 = f[8];
crypto_int32 f9 = f[9];
crypto_int32 f0_2 = 2 * f0;
crypto_int32 f1_2 = 2 * f1;
crypto_int32 f2_2 = 2 * f2;
crypto_int32 f3_2 = 2 * f3;
crypto_int32 f4_2 = 2 * f4;
crypto_int32 f5_2 = 2 * f5;
crypto_int32 f6_2 = 2 * f6;
crypto_int32 f7_2 = 2 * f7;
crypto_int32 f5_38 = 38 * f5; /* 1.959375*2^30 */
crypto_int32 f6_19 = 19 * f6; /* 1.959375*2^30 */
crypto_int32 f7_38 = 38 * f7; /* 1.959375*2^30 */
crypto_int32 f8_19 = 19 * f8; /* 1.959375*2^30 */
crypto_int32 f9_38 = 38 * f9; /* 1.959375*2^30 */
crypto_int64 f0f0 = f0 * (crypto_int64) f0;
crypto_int64 f0f1_2 = f0_2 * (crypto_int64) f1;
crypto_int64 f0f2_2 = f0_2 * (crypto_int64) f2;
crypto_int64 f0f3_2 = f0_2 * (crypto_int64) f3;
crypto_int64 f0f4_2 = f0_2 * (crypto_int64) f4;
crypto_int64 f0f5_2 = f0_2 * (crypto_int64) f5;
crypto_int64 f0f6_2 = f0_2 * (crypto_int64) f6;
crypto_int64 f0f7_2 = f0_2 * (crypto_int64) f7;
crypto_int64 f0f8_2 = f0_2 * (crypto_int64) f8;
crypto_int64 f0f9_2 = f0_2 * (crypto_int64) f9;
crypto_int64 f1f1_2 = f1_2 * (crypto_int64) f1;
crypto_int64 f1f2_2 = f1_2 * (crypto_int64) f2;
crypto_int64 f1f3_4 = f1_2 * (crypto_int64) f3_2;
crypto_int64 f1f4_2 = f1_2 * (crypto_int64) f4;
crypto_int64 f1f5_4 = f1_2 * (crypto_int64) f5_2;
crypto_int64 f1f6_2 = f1_2 * (crypto_int64) f6;
crypto_int64 f1f7_4 = f1_2 * (crypto_int64) f7_2;
crypto_int64 f1f8_2 = f1_2 * (crypto_int64) f8;
crypto_int64 f1f9_76 = f1_2 * (crypto_int64) f9_38;
crypto_int64 f2f2 = f2 * (crypto_int64) f2;
crypto_int64 f2f3_2 = f2_2 * (crypto_int64) f3;
crypto_int64 f2f4_2 = f2_2 * (crypto_int64) f4;
crypto_int64 f2f5_2 = f2_2 * (crypto_int64) f5;
crypto_int64 f2f6_2 = f2_2 * (crypto_int64) f6;
crypto_int64 f2f7_2 = f2_2 * (crypto_int64) f7;
crypto_int64 f2f8_38 = f2_2 * (crypto_int64) f8_19;
crypto_int64 f2f9_38 = f2 * (crypto_int64) f9_38;
crypto_int64 f3f3_2 = f3_2 * (crypto_int64) f3;
crypto_int64 f3f4_2 = f3_2 * (crypto_int64) f4;
crypto_int64 f3f5_4 = f3_2 * (crypto_int64) f5_2;
crypto_int64 f3f6_2 = f3_2 * (crypto_int64) f6;
crypto_int64 f3f7_76 = f3_2 * (crypto_int64) f7_38;
crypto_int64 f3f8_38 = f3_2 * (crypto_int64) f8_19;
crypto_int64 f3f9_76 = f3_2 * (crypto_int64) f9_38;
crypto_int64 f4f4 = f4 * (crypto_int64) f4;
crypto_int64 f4f5_2 = f4_2 * (crypto_int64) f5;
crypto_int64 f4f6_38 = f4_2 * (crypto_int64) f6_19;
crypto_int64 f4f7_38 = f4 * (crypto_int64) f7_38;
crypto_int64 f4f8_38 = f4_2 * (crypto_int64) f8_19;
crypto_int64 f4f9_38 = f4 * (crypto_int64) f9_38;
crypto_int64 f5f5_38 = f5 * (crypto_int64) f5_38;
crypto_int64 f5f6_38 = f5_2 * (crypto_int64) f6_19;
crypto_int64 f5f7_76 = f5_2 * (crypto_int64) f7_38;
crypto_int64 f5f8_38 = f5_2 * (crypto_int64) f8_19;
crypto_int64 f5f9_76 = f5_2 * (crypto_int64) f9_38;
crypto_int64 f6f6_19 = f6 * (crypto_int64) f6_19;
crypto_int64 f6f7_38 = f6 * (crypto_int64) f7_38;
crypto_int64 f6f8_38 = f6_2 * (crypto_int64) f8_19;
crypto_int64 f6f9_38 = f6 * (crypto_int64) f9_38;
crypto_int64 f7f7_38 = f7 * (crypto_int64) f7_38;
crypto_int64 f7f8_38 = f7_2 * (crypto_int64) f8_19;
crypto_int64 f7f9_76 = f7_2 * (crypto_int64) f9_38;
crypto_int64 f8f8_19 = f8 * (crypto_int64) f8_19;
crypto_int64 f8f9_38 = f8 * (crypto_int64) f9_38;
crypto_int64 f9f9_38 = f9 * (crypto_int64) f9_38;
crypto_int64 h0 = f0f0 +f1f9_76+f2f8_38+f3f7_76+f4f6_38+f5f5_38;
crypto_int64 h1 = f0f1_2+f2f9_38+f3f8_38+f4f7_38+f5f6_38;
crypto_int64 h2 = f0f2_2+f1f1_2 +f3f9_76+f4f8_38+f5f7_76+f6f6_19;
crypto_int64 h3 = f0f3_2+f1f2_2 +f4f9_38+f5f8_38+f6f7_38;
crypto_int64 h4 = f0f4_2+f1f3_4 +f2f2 +f5f9_76+f6f8_38+f7f7_38;
crypto_int64 h5 = f0f5_2+f1f4_2 +f2f3_2 +f6f9_38+f7f8_38;
crypto_int64 h6 = f0f6_2+f1f5_4 +f2f4_2 +f3f3_2 +f7f9_76+f8f8_19;
crypto_int64 h7 = f0f7_2+f1f6_2 +f2f5_2 +f3f4_2 +f8f9_38;
crypto_int64 h8 = f0f8_2+f1f7_4 +f2f6_2 +f3f5_4 +f4f4 +f9f9_38;
crypto_int64 h9 = f0f9_2+f1f8_2 +f2f7_2 +f3f6_2 +f4f5_2;
crypto_int64 carry0;
crypto_int64 carry1;
crypto_int64 carry2;
crypto_int64 carry3;
crypto_int64 carry4;
crypto_int64 carry5;
crypto_int64 carry6;
crypto_int64 carry7;
crypto_int64 carry8;
crypto_int64 carry9;
h0 += h0;
h1 += h1;
h2 += h2;
h3 += h3;
h4 += h4;
h5 += h5;
h6 += h6;
h7 += h7;
h8 += h8;
h9 += h9;
carry0 = (h0 + (crypto_int64) (1<<25)) >> 26; h1 += carry0; h0 -= carry0 << 26;
carry4 = (h4 + (crypto_int64) (1<<25)) >> 26; h5 += carry4; h4 -= carry4 << 26;
carry1 = (h1 + (crypto_int64) (1<<24)) >> 25; h2 += carry1; h1 -= carry1 << 25;
carry5 = (h5 + (crypto_int64) (1<<24)) >> 25; h6 += carry5; h5 -= carry5 << 25;
carry2 = (h2 + (crypto_int64) (1<<25)) >> 26; h3 += carry2; h2 -= carry2 << 26;
carry6 = (h6 + (crypto_int64) (1<<25)) >> 26; h7 += carry6; h6 -= carry6 << 26;
carry3 = (h3 + (crypto_int64) (1<<24)) >> 25; h4 += carry3; h3 -= carry3 << 25;
carry7 = (h7 + (crypto_int64) (1<<24)) >> 25; h8 += carry7; h7 -= carry7 << 25;
carry4 = (h4 + (crypto_int64) (1<<25)) >> 26; h5 += carry4; h4 -= carry4 << 26;
carry8 = (h8 + (crypto_int64) (1<<25)) >> 26; h9 += carry8; h8 -= carry8 << 26;
carry9 = (h9 + (crypto_int64) (1<<24)) >> 25; h0 += carry9 * 19; h9 -= carry9 << 25;
carry0 = (h0 + (crypto_int64) (1<<25)) >> 26; h1 += carry0; h0 -= carry0 << 26;
h[0] = h0;
h[1] = h1;
h[2] = h2;
h[3] = h3;
h[4] = h4;
h[5] = h5;
h[6] = h6;
h[7] = h7;
h[8] = h8;
h[9] = h9;
}
/*
h = f * g
Can overlap h with f or g.
Preconditions:
|f| bounded by 1.65*2^26,1.65*2^25,1.65*2^26,1.65*2^25,etc.
|g| bounded by 1.65*2^26,1.65*2^25,1.65*2^26,1.65*2^25,etc.
Postconditions:
|h| bounded by 1.01*2^25,1.01*2^24,1.01*2^25,1.01*2^24,etc.
*/
/*