vendor/libsodium/src/libsodium/crypto_scalarmult/curve25519/ref10/x25519_ref10.c in rbnacl-libsodium-1.0.11 vs vendor/libsodium/src/libsodium/crypto_scalarmult/curve25519/ref10/x25519_ref10.c in rbnacl-libsodium-1.0.13

- old
+ new

@@ -2,86 +2,87 @@ #include <stddef.h> #include <stdint.h> #ifndef HAVE_TI_MODE -#include "utils.h" -#include "x25519_ref10.h" #include "../scalarmult_curve25519.h" #include "private/curve25519_ref10.h" +#include "utils.h" +#include "x25519_ref10.h" /* Replace (f,g) with (g,f) if b == 1; replace (f,g) with (f,g) if b == 0. Preconditions: b in {0,1}. */ static void -fe_cswap(fe f,fe g,unsigned int b) +fe_cswap(fe f, fe g, unsigned int b) { - int32_t f0 = f[0]; - int32_t f1 = f[1]; - int32_t f2 = f[2]; - int32_t f3 = f[3]; - int32_t f4 = f[4]; - int32_t f5 = f[5]; - int32_t f6 = f[6]; - int32_t f7 = f[7]; - int32_t f8 = f[8]; - int32_t f9 = f[9]; - int32_t g0 = g[0]; - int32_t g1 = g[1]; - int32_t g2 = g[2]; - int32_t g3 = g[3]; - int32_t g4 = g[4]; - int32_t g5 = g[5]; - int32_t g6 = g[6]; - int32_t g7 = g[7]; - int32_t g8 = g[8]; - int32_t g9 = g[9]; - int32_t x0 = f0 ^ g0; - int32_t x1 = f1 ^ g1; - int32_t x2 = f2 ^ g2; - int32_t x3 = f3 ^ g3; - int32_t x4 = f4 ^ g4; - int32_t x5 = f5 ^ g5; - int32_t x6 = f6 ^ g6; - int32_t x7 = f7 ^ g7; - int32_t x8 = f8 ^ g8; - int32_t x9 = f9 ^ g9; - b = (unsigned int) (- (int) 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; - g[0] = g0 ^ x0; - g[1] = g1 ^ x1; - g[2] = g2 ^ x2; - g[3] = g3 ^ x3; - g[4] = g4 ^ x4; - g[5] = g5 ^ x5; - g[6] = g6 ^ x6; - g[7] = g7 ^ x7; - g[8] = g8 ^ x8; - g[9] = g9 ^ x9; + int32_t f0 = f[0]; + int32_t f1 = f[1]; + int32_t f2 = f[2]; + int32_t f3 = f[3]; + int32_t f4 = f[4]; + int32_t f5 = f[5]; + int32_t f6 = f[6]; + int32_t f7 = f[7]; + int32_t f8 = f[8]; + int32_t f9 = f[9]; + int32_t g0 = g[0]; + int32_t g1 = g[1]; + int32_t g2 = g[2]; + int32_t g3 = g[3]; + int32_t g4 = g[4]; + int32_t g5 = g[5]; + int32_t g6 = g[6]; + int32_t g7 = g[7]; + int32_t g8 = g[8]; + int32_t g9 = g[9]; + int32_t x0 = f0 ^ g0; + int32_t x1 = f1 ^ g1; + int32_t x2 = f2 ^ g2; + int32_t x3 = f3 ^ g3; + int32_t x4 = f4 ^ g4; + int32_t x5 = f5 ^ g5; + int32_t x6 = f6 ^ g6; + int32_t x7 = f7 ^ g7; + int32_t x8 = f8 ^ g8; + int32_t x9 = f9 ^ g9; + + b = (unsigned int)(-(int)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; + g[0] = g0 ^ x0; + g[1] = g1 ^ x1; + g[2] = g2 ^ x2; + g[3] = g3 ^ x3; + g[4] = g4 ^ x4; + g[5] = g5 ^ x5; + g[6] = g6 ^ x6; + g[7] = g7 ^ x7; + g[8] = g8 ^ x8; + g[9] = g9 ^ x9; } /* h = f * 121666 Can overlap h with f. @@ -92,164 +93,190 @@ Postconditions: |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc. */ static void -fe_mul121666(fe h,const fe f) +fe_mul121666(fe h, const fe f) { - int32_t f0 = f[0]; - int32_t f1 = f[1]; - int32_t f2 = f[2]; - int32_t f3 = f[3]; - int32_t f4 = f[4]; - int32_t f5 = f[5]; - int32_t f6 = f[6]; - int32_t f7 = f[7]; - int32_t f8 = f[8]; - int32_t f9 = f[9]; - int64_t h0 = f0 * (int64_t) 121666; - int64_t h1 = f1 * (int64_t) 121666; - int64_t h2 = f2 * (int64_t) 121666; - int64_t h3 = f3 * (int64_t) 121666; - int64_t h4 = f4 * (int64_t) 121666; - int64_t h5 = f5 * (int64_t) 121666; - int64_t h6 = f6 * (int64_t) 121666; - int64_t h7 = f7 * (int64_t) 121666; - int64_t h8 = f8 * (int64_t) 121666; - int64_t h9 = f9 * (int64_t) 121666; - int64_t carry0; - int64_t carry1; - int64_t carry2; - int64_t carry3; - int64_t carry4; - int64_t carry5; - int64_t carry6; - int64_t carry7; - int64_t carry8; - int64_t carry9; + int32_t f0 = f[0]; + int32_t f1 = f[1]; + int32_t f2 = f[2]; + int32_t f3 = f[3]; + int32_t f4 = f[4]; + int32_t f5 = f[5]; + int32_t f6 = f[6]; + int32_t f7 = f[7]; + int32_t f8 = f[8]; + int32_t f9 = f[9]; + int64_t h0 = f0 * (int64_t)121666; + int64_t h1 = f1 * (int64_t)121666; + int64_t h2 = f2 * (int64_t)121666; + int64_t h3 = f3 * (int64_t)121666; + int64_t h4 = f4 * (int64_t)121666; + int64_t h5 = f5 * (int64_t)121666; + int64_t h6 = f6 * (int64_t)121666; + int64_t h7 = f7 * (int64_t)121666; + int64_t h8 = f8 * (int64_t)121666; + int64_t h9 = f9 * (int64_t)121666; + int64_t carry0; + int64_t carry1; + int64_t carry2; + int64_t carry3; + int64_t carry4; + int64_t carry5; + int64_t carry6; + int64_t carry7; + int64_t carry8; + int64_t carry9; - carry9 = (h9 + ((int64_t) 1 << 24)) >> 25; h0 += carry9 * 19; h9 -= carry9 * ((int64_t) 1 << 25); - carry1 = (h1 + ((int64_t) 1 << 24)) >> 25; h2 += carry1; h1 -= carry1 * ((int64_t) 1 << 25); - carry3 = (h3 + ((int64_t) 1 << 24)) >> 25; h4 += carry3; h3 -= carry3 * ((int64_t) 1 << 25); - carry5 = (h5 + ((int64_t) 1 << 24)) >> 25; h6 += carry5; h5 -= carry5 * ((int64_t) 1 << 25); - carry7 = (h7 + ((int64_t) 1 << 24)) >> 25; h8 += carry7; h7 -= carry7 * ((int64_t) 1 << 25); + carry9 = (h9 + ((int64_t)1 << 24)) >> 25; + h0 += carry9 * 19; + h9 -= carry9 * ((int64_t)1 << 25); + carry1 = (h1 + ((int64_t)1 << 24)) >> 25; + h2 += carry1; + h1 -= carry1 * ((int64_t)1 << 25); + carry3 = (h3 + ((int64_t)1 << 24)) >> 25; + h4 += carry3; + h3 -= carry3 * ((int64_t)1 << 25); + carry5 = (h5 + ((int64_t)1 << 24)) >> 25; + h6 += carry5; + h5 -= carry5 * ((int64_t)1 << 25); + carry7 = (h7 + ((int64_t)1 << 24)) >> 25; + h8 += carry7; + h7 -= carry7 * ((int64_t)1 << 25); - carry0 = (h0 + ((int64_t) 1 << 25)) >> 26; h1 += carry0; h0 -= carry0 * ((int64_t) 1 << 26); - carry2 = (h2 + ((int64_t) 1 << 25)) >> 26; h3 += carry2; h2 -= carry2 * ((int64_t) 1 << 26); - carry4 = (h4 + ((int64_t) 1 << 25)) >> 26; h5 += carry4; h4 -= carry4 * ((int64_t) 1 << 26); - carry6 = (h6 + ((int64_t) 1 << 25)) >> 26; h7 += carry6; h6 -= carry6 * ((int64_t) 1 << 26); - carry8 = (h8 + ((int64_t) 1 << 25)) >> 26; h9 += carry8; h8 -= carry8 * ((int64_t) 1 << 26); + carry0 = (h0 + ((int64_t)1 << 25)) >> 26; + h1 += carry0; + h0 -= carry0 * ((int64_t)1 << 26); + carry2 = (h2 + ((int64_t)1 << 25)) >> 26; + h3 += carry2; + h2 -= carry2 * ((int64_t)1 << 26); + carry4 = (h4 + ((int64_t)1 << 25)) >> 26; + h5 += carry4; + h4 -= carry4 * ((int64_t)1 << 26); + carry6 = (h6 + ((int64_t)1 << 25)) >> 26; + h7 += carry6; + h6 -= carry6 * ((int64_t)1 << 26); + carry8 = (h8 + ((int64_t)1 << 25)) >> 26; + h9 += carry8; + h8 -= carry8 * ((int64_t)1 << 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[0] = (int32_t) h0; + h[1] = (int32_t) h1; + h[2] = (int32_t) h2; + h[3] = (int32_t) h3; + h[4] = (int32_t) h4; + h[5] = (int32_t) h5; + h[6] = (int32_t) h6; + h[7] = (int32_t) h7; + h[8] = (int32_t) h8; + h[9] = (int32_t) h9; } static int crypto_scalarmult_curve25519_ref10(unsigned char *q, const unsigned char *n, const unsigned char *p) { - unsigned char e[32]; - unsigned int i; - fe x1; - fe x2; - fe z2; - fe x3; - fe z3; - fe tmp0; - fe tmp1; - int pos; - unsigned int swap; - unsigned int b; + unsigned char e[32]; + unsigned int i; + fe x1; + fe x2; + fe z2; + fe x3; + fe z3; + fe tmp0; + fe tmp1; + int pos; + unsigned int swap; + unsigned int b; - for (i = 0;i < 32;++i) e[i] = n[i]; - e[0] &= 248; - e[31] &= 127; - e[31] |= 64; - fe_frombytes(x1,p); - fe_1(x2); - fe_0(z2); - fe_copy(x3,x1); - fe_1(z3); + for (i = 0; i < 32; ++i) { + e[i] = n[i]; + } + e[0] &= 248; + e[31] &= 127; + e[31] |= 64; + fe_frombytes(x1, p); + fe_1(x2); + fe_0(z2); + fe_copy(x3, x1); + fe_1(z3); - swap = 0; - for (pos = 254;pos >= 0;--pos) { - b = e[pos / 8] >> (pos & 7); - b &= 1; - swap ^= b; - fe_cswap(x2,x3,swap); - fe_cswap(z2,z3,swap); - swap = b; - fe_sub(tmp0,x3,z3); - fe_sub(tmp1,x2,z2); - fe_add(x2,x2,z2); - fe_add(z2,x3,z3); - fe_mul(z3,tmp0,x2); - fe_mul(z2,z2,tmp1); - fe_sq(tmp0,tmp1); - fe_sq(tmp1,x2); - fe_add(x3,z3,z2); - fe_sub(z2,z3,z2); - fe_mul(x2,tmp1,tmp0); - fe_sub(tmp1,tmp1,tmp0); - fe_sq(z2,z2); - fe_mul121666(z3,tmp1); - fe_sq(x3,x3); - fe_add(tmp0,tmp0,z3); - fe_mul(z3,x1,z2); - fe_mul(z2,tmp1,tmp0); - } - fe_cswap(x2,x3,swap); - fe_cswap(z2,z3,swap); + swap = 0; + for (pos = 254; pos >= 0; --pos) { + b = e[pos / 8] >> (pos & 7); + b &= 1; + swap ^= b; + fe_cswap(x2, x3, swap); + fe_cswap(z2, z3, swap); + swap = b; + fe_sub(tmp0, x3, z3); + fe_sub(tmp1, x2, z2); + fe_add(x2, x2, z2); + fe_add(z2, x3, z3); + fe_mul(z3, tmp0, x2); + fe_mul(z2, z2, tmp1); + fe_sq(tmp0, tmp1); + fe_sq(tmp1, x2); + fe_add(x3, z3, z2); + fe_sub(z2, z3, z2); + fe_mul(x2, tmp1, tmp0); + fe_sub(tmp1, tmp1, tmp0); + fe_sq(z2, z2); + fe_mul121666(z3, tmp1); + fe_sq(x3, x3); + fe_add(tmp0, tmp0, z3); + fe_mul(z3, x1, z2); + fe_mul(z2, tmp1, tmp0); + } + fe_cswap(x2, x3, swap); + fe_cswap(z2, z3, swap); - fe_invert(z2,z2); - fe_mul(x2,x2,z2); - fe_tobytes(q,x2); - return 0; + fe_invert(z2, z2); + fe_mul(x2, x2, z2); + fe_tobytes(q, x2); + + return 0; } static void edwards_to_montgomery(fe montgomeryX, const fe edwardsY, const fe edwardsZ) { - fe tempX; - fe tempZ; + fe tempX; + fe tempZ; - fe_add(tempX, edwardsZ, edwardsY); - fe_sub(tempZ, edwardsZ, edwardsY); - fe_invert(tempZ, tempZ); - fe_mul(montgomeryX, tempX, tempZ); + fe_add(tempX, edwardsZ, edwardsY); + fe_sub(tempZ, edwardsZ, edwardsY); + fe_invert(tempZ, tempZ); + fe_mul(montgomeryX, tempX, tempZ); } static int crypto_scalarmult_curve25519_ref10_base(unsigned char *q, const unsigned char *n) { - unsigned char e[32]; - ge_p3 A; - fe pk; - unsigned int i; + unsigned char e[32]; + ge_p3 A; + fe pk; + unsigned int i; - for (i = 0;i < 32;++i) e[i] = n[i]; - e[0] &= 248; - e[31] &= 127; - e[31] |= 64; - ge_scalarmult_base(&A, e); - edwards_to_montgomery(pk, A.Y, A.Z); - fe_tobytes(q, pk); - return 0; + for (i = 0; i < 32; ++i) { + e[i] = n[i]; + } + e[0] &= 248; + e[31] &= 127; + e[31] |= 64; + ge_scalarmult_base(&A, e); + edwards_to_montgomery(pk, A.Y, A.Z); + fe_tobytes(q, pk); + + return 0; } struct crypto_scalarmult_curve25519_implementation -crypto_scalarmult_curve25519_ref10_implementation = { - SODIUM_C99(.mult = ) crypto_scalarmult_curve25519_ref10, - SODIUM_C99(.mult_base = ) crypto_scalarmult_curve25519_ref10_base -}; + crypto_scalarmult_curve25519_ref10_implementation = { + SODIUM_C99(.mult =) crypto_scalarmult_curve25519_ref10, + SODIUM_C99(.mult_base =) crypto_scalarmult_curve25519_ref10_base + }; #endif