diff options
| -rw-r--r-- | libbb/hash_md5_sha.c | 256 |
1 files changed, 242 insertions, 14 deletions
diff --git a/libbb/hash_md5_sha.c b/libbb/hash_md5_sha.c index 3f743ac75..dff583ad1 100644 --- a/libbb/hash_md5_sha.c +++ b/libbb/hash_md5_sha.c @@ -926,10 +926,81 @@ void FAST_FUNC sha512_end(sha512_ctx_t *ctx, void *resbuf) # define SHA3_SMALL CONFIG_SHA3_SMALL #endif +#define OPTIMIZE_SHA3_FOR_32 0 +/* + * SHA3 can be optimized for 32-bit CPUs with bit-slicing: + * every 64-bit word of state[] can be split into two 32-bit words + * by even/odd bits. In this form, all rotations of sha3 round + * are 32-bit - and there are lots of them. + * However, it requires either splitting/combining state words + * before/after sha3 round (code does this now) + * or shuffling bits before xor'ing them into state and in sha3_end. + * Without shuffling, bit-slicing results in -130 bytes of code + * and marginal speedup (but of course it gives wrong result). + * With shuffling it works, but +260 code bytes, and slower. + * Disabled for now: + */ +#if 0 /* LONG_MAX == 0x7fffffff */ +# undef OPTIMIZE_SHA3_FOR_32 +# define OPTIMIZE_SHA3_FOR_32 1 +#endif + enum { SHA3_IBLK_BYTES = 72, /* 576 bits / 8 */ }; +#if OPTIMIZE_SHA3_FOR_32 +/* This splits every 64-bit word into a pair of 32-bit words, + * even bits go into first word, odd bits go to second one. + * The conversion is done in-place. + */ +static void split_halves(uint64_t *state) +{ + /* Credit: Henry S. Warren, Hacker's Delight, Addison-Wesley, 2002 */ + uint32_t *s32 = (uint32_t*)state; + uint32_t t, x0, x1; + int i; + for (i = 24; i >= 0; --i) { + x0 = s32[0]; + t = (x0 ^ (x0 >> 1)) & 0x22222222; x0 = x0 ^ t ^ (t << 1); + t = (x0 ^ (x0 >> 2)) & 0x0C0C0C0C; x0 = x0 ^ t ^ (t << 2); + t = (x0 ^ (x0 >> 4)) & 0x00F000F0; x0 = x0 ^ t ^ (t << 4); + t = (x0 ^ (x0 >> 8)) & 0x0000FF00; x0 = x0 ^ t ^ (t << 8); + x1 = s32[1]; + t = (x1 ^ (x1 >> 1)) & 0x22222222; x1 = x1 ^ t ^ (t << 1); + t = (x1 ^ (x1 >> 2)) & 0x0C0C0C0C; x1 = x1 ^ t ^ (t << 2); + t = (x1 ^ (x1 >> 4)) & 0x00F000F0; x1 = x1 ^ t ^ (t << 4); + t = (x1 ^ (x1 >> 8)) & 0x0000FF00; x1 = x1 ^ t ^ (t << 8); + *s32++ = (x0 & 0x0000FFFF) | (x1 << 16); + *s32++ = (x0 >> 16) | (x1 & 0xFFFF0000); + } +} +/* The reverse operation */ +static void combine_halves(uint64_t *state) +{ + uint32_t *s32 = (uint32_t*)state; + uint32_t t, x0, x1; + int i; + for (i = 24; i >= 0; --i) { + x0 = s32[0]; + x1 = s32[1]; + t = (x0 & 0x0000FFFF) | (x1 << 16); + x1 = (x0 >> 16) | (x1 & 0xFFFF0000); + x0 = t; + t = (x0 ^ (x0 >> 8)) & 0x0000FF00; x0 = x0 ^ t ^ (t << 8); + t = (x0 ^ (x0 >> 4)) & 0x00F000F0; x0 = x0 ^ t ^ (t << 4); + t = (x0 ^ (x0 >> 2)) & 0x0C0C0C0C; x0 = x0 ^ t ^ (t << 2); + t = (x0 ^ (x0 >> 1)) & 0x22222222; x0 = x0 ^ t ^ (t << 1); + *s32++ = x0; + t = (x1 ^ (x1 >> 8)) & 0x0000FF00; x1 = x1 ^ t ^ (t << 8); + t = (x1 ^ (x1 >> 4)) & 0x00F000F0; x1 = x1 ^ t ^ (t << 4); + t = (x1 ^ (x1 >> 2)) & 0x0C0C0C0C; x1 = x1 ^ t ^ (t << 2); + t = (x1 ^ (x1 >> 1)) & 0x22222222; x1 = x1 ^ t ^ (t << 1); + *s32++ = x1; + } +} +#endif + /* * In the crypto literature this function is usually called Keccak-f(). */ @@ -937,6 +1008,164 @@ static void sha3_process_block72(uint64_t *state) { enum { NROUNDS = 24 }; +#if OPTIMIZE_SHA3_FOR_32 + /* + static const uint32_t IOTA_CONST_0[NROUNDS] = { + 0x00000001UL, + 0x00000000UL, + 0x00000000UL, + 0x00000000UL, + 0x00000001UL, + 0x00000001UL, + 0x00000001UL, + 0x00000001UL, + 0x00000000UL, + 0x00000000UL, + 0x00000001UL, + 0x00000000UL, + 0x00000001UL, + 0x00000001UL, + 0x00000001UL, + 0x00000001UL, + 0x00000000UL, + 0x00000000UL, + 0x00000000UL, + 0x00000000UL, + 0x00000001UL, + 0x00000000UL, + 0x00000001UL, + 0x00000000UL, + }; + ** bits are in lsb: 0101 0000 1111 0100 1111 0001 + */ + uint32_t IOTA_CONST_0bits = (uint32_t)(0x0050f4f1); + static const uint32_t IOTA_CONST_1[NROUNDS] = { + 0x00000000UL, + 0x00000089UL, + 0x8000008bUL, + 0x80008080UL, + 0x0000008bUL, + 0x00008000UL, + 0x80008088UL, + 0x80000082UL, + 0x0000000bUL, + 0x0000000aUL, + 0x00008082UL, + 0x00008003UL, + 0x0000808bUL, + 0x8000000bUL, + 0x8000008aUL, + 0x80000081UL, + 0x80000081UL, + 0x80000008UL, + 0x00000083UL, + 0x80008003UL, + 0x80008088UL, + 0x80000088UL, + 0x00008000UL, + 0x80008082UL, + }; + + uint32_t *const s32 = (uint32_t*)state; + unsigned round; + + split_halves(state); + + for (round = 0; round < NROUNDS; round++) { + unsigned x; + + /* Theta */ + { + uint32_t BC[20]; + for (x = 0; x < 10; ++x) { + BC[x+10] = BC[x] = s32[x]^s32[x+10]^s32[x+20]^s32[x+30]^s32[x+40]; + } + for (x = 0; x < 10; x += 2) { + uint32_t ta, tb; + ta = BC[x+8] ^ rotl32(BC[x+3], 1); + tb = BC[x+9] ^ BC[x+2]; + s32[x+0] ^= ta; + s32[x+1] ^= tb; + s32[x+10] ^= ta; + s32[x+11] ^= tb; + s32[x+20] ^= ta; + s32[x+21] ^= tb; + s32[x+30] ^= ta; + s32[x+31] ^= tb; + s32[x+40] ^= ta; + s32[x+41] ^= tb; + } + } + /* RhoPi */ + { + uint32_t t0a,t0b, t1a,t1b; + t1a = s32[1*2+0]; + t1b = s32[1*2+1]; + +#define RhoPi(PI_LANE, ROT_CONST) \ + t0a = s32[PI_LANE*2+0];\ + t0b = s32[PI_LANE*2+1];\ + if (ROT_CONST & 1) {\ + s32[PI_LANE*2+0] = rotl32(t1b, ROT_CONST/2+1);\ + s32[PI_LANE*2+1] = ROT_CONST == 1 ? t1a : rotl32(t1a, ROT_CONST/2+0);\ + } else {\ + s32[PI_LANE*2+0] = rotl32(t1a, ROT_CONST/2);\ + s32[PI_LANE*2+1] = rotl32(t1b, ROT_CONST/2);\ + }\ + t1a = t0a; t1b = t0b; + + RhoPi(10, 1) + RhoPi( 7, 3) + RhoPi(11, 6) + RhoPi(17,10) + RhoPi(18,15) + RhoPi( 3,21) + RhoPi( 5,28) + RhoPi(16,36) + RhoPi( 8,45) + RhoPi(21,55) + RhoPi(24, 2) + RhoPi( 4,14) + RhoPi(15,27) + RhoPi(23,41) + RhoPi(19,56) + RhoPi(13, 8) + RhoPi(12,25) + RhoPi( 2,43) + RhoPi(20,62) + RhoPi(14,18) + RhoPi(22,39) + RhoPi( 9,61) + RhoPi( 6,20) + RhoPi( 1,44) +#undef RhoPi + } + /* Chi */ + for (x = 0; x <= 20; x += 5) { + /* + * Can write this in terms of uint32 too, + * but why? compiler does it automatically. + */ + uint64_t BC0, BC1, BC2, BC3, BC4; + BC0 = state[x + 0]; + BC1 = state[x + 1]; + BC2 = state[x + 2]; + state[x + 0] = BC0 ^ ((~BC1) & BC2); + BC3 = state[x + 3]; + state[x + 1] = BC1 ^ ((~BC2) & BC3); + BC4 = state[x + 4]; + state[x + 2] = BC2 ^ ((~BC3) & BC4); + state[x + 3] = BC3 ^ ((~BC4) & BC0); + state[x + 4] = BC4 ^ ((~BC0) & BC1); + } + /* Iota */ + s32[0] ^= IOTA_CONST_0bits & 1; + IOTA_CONST_0bits >>= 1; + s32[1] ^= IOTA_CONST_1[round]; + } + + combine_halves(state); +#else /* Elements should be 64-bit, but top half is always zero or 0x80000000. * We encode 63rd bits in a separate word below. * Same is true for 31th bits, which lets us use 16-bit table instead of 64-bit. @@ -983,7 +1212,7 @@ static void sha3_process_block72(uint64_t *state) }; /*static const uint8_t MOD5[10] = { 0, 1, 2, 3, 4, 0, 1, 2, 3, 4, };*/ - unsigned x, y; + unsigned x; unsigned round; if (BB_BIG_ENDIAN) { @@ -1045,22 +1274,20 @@ static void sha3_process_block72(uint64_t *state) RhoPi_twice(20); RhoPi_twice(22); #undef RhoPi_twice } - /* Chi */ - for (y = 0; y <= 20; y += 5) { + for (x = 0; x <= 20; x += 5) { uint64_t BC0, BC1, BC2, BC3, BC4; - BC0 = state[y + 0]; - BC1 = state[y + 1]; - BC2 = state[y + 2]; - state[y + 0] = BC0 ^ ((~BC1) & BC2); - BC3 = state[y + 3]; - state[y + 1] = BC1 ^ ((~BC2) & BC3); - BC4 = state[y + 4]; - state[y + 2] = BC2 ^ ((~BC3) & BC4); - state[y + 3] = BC3 ^ ((~BC4) & BC0); - state[y + 4] = BC4 ^ ((~BC0) & BC1); + BC0 = state[x + 0]; + BC1 = state[x + 1]; + BC2 = state[x + 2]; + state[x + 0] = BC0 ^ ((~BC1) & BC2); + BC3 = state[x + 3]; + state[x + 1] = BC1 ^ ((~BC2) & BC3); + BC4 = state[x + 4]; + state[x + 2] = BC2 ^ ((~BC3) & BC4); + state[x + 3] = BC3 ^ ((~BC4) & BC0); + state[x + 4] = BC4 ^ ((~BC0) & BC1); } - /* Iota */ state[0] ^= IOTA_CONST[round] | (uint32_t)((IOTA_CONST_bit31 << round) & 0x80000000) @@ -1072,6 +1299,7 @@ static void sha3_process_block72(uint64_t *state) state[x] = SWAP_LE64(state[x]); } } +#endif } void FAST_FUNC sha3_begin(sha3_ctx_t *ctx) |