diff options
| -rw-r--r-- | lib/alg-sha256.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/lib/alg-sha256.c b/lib/alg-sha256.c index f448e4f..f83a4e1 100644 --- a/lib/alg-sha256.c +++ b/lib/alg-sha256.c @@ -1,6 +1,6 @@ /*- * Copyright 2005-2016 Colin Percival - * Copyright 2016-2018 Alexander Peslyak + * Copyright 2016-2018,2021 Alexander Peslyak * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -65,7 +65,11 @@ static const uint32_t Krnd[64] = { /* Elementary functions used by SHA256 */ #define Ch(x, y, z) ((x & (y ^ z)) ^ z) -#define Maj(x, y, z) ((x & (y | z)) | (y & z)) +#if 1 /* Explicit caching/reuse of common subexpression between rounds */ +#define Maj(x, y, z) (y ^ ((x_xor_y = x ^ y) & y_xor_z)) +#else /* Let the compiler cache/reuse or not */ +#define Maj(x, y, z) (y ^ ((x ^ y) & (y ^ z))) +#endif #define SHR(x, n) (x >> n) #define ROTR(x, n) ((x >> n) | (x << (32 - n))) #define S0(x) (ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22)) @@ -77,7 +81,8 @@ static const uint32_t Krnd[64] = { #define RND(a, b, c, d, e, f, g, h, k) \ h += S1(e) + Ch(e, f, g) + k; \ d += h; \ - h += S0(a) + Maj(a, b, c); + h += S0(a) + Maj(a, b, c); \ + y_xor_z = x_xor_y; /* Adjusted round function for rotating state */ #define RNDr(S, W, i, ii) \ @@ -110,6 +115,7 @@ SHA256_Transform(uint32_t state[static restrict 8], /* 3. Mix. */ for (i = 0; i <= 48; i += 16) { + uint32_t x_xor_y, y_xor_z = S[(65 - i) % 8] ^ S[(66 - i) % 8]; RNDr(S, W, 0, i); RNDr(S, W, 1, i); RNDr(S, W, 2, i); |