diff options
Diffstat (limited to 'third_party/bearssl/src/ghash_ctmul64.c')
| -rw-r--r-- | third_party/bearssl/src/ghash_ctmul64.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/third_party/bearssl/src/ghash_ctmul64.c b/third_party/bearssl/src/ghash_ctmul64.c new file mode 100644 index 0000000..a46f16f --- /dev/null +++ b/third_party/bearssl/src/ghash_ctmul64.c @@ -0,0 +1,154 @@ +/* + * Copyright (c) 2016 Thomas Pornin <[email protected]> + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "inner.h" + +/* + * This is the 64-bit variant of br_ghash_ctmul32(), with 64-bit operands + * and bit reversal of 64-bit words. + */ + +static inline uint64_t +bmul64(uint64_t x, uint64_t y) +{ + uint64_t x0, x1, x2, x3; + uint64_t y0, y1, y2, y3; + uint64_t z0, z1, z2, z3; + + x0 = x & (uint64_t)0x1111111111111111; + x1 = x & (uint64_t)0x2222222222222222; + x2 = x & (uint64_t)0x4444444444444444; + x3 = x & (uint64_t)0x8888888888888888; + y0 = y & (uint64_t)0x1111111111111111; + y1 = y & (uint64_t)0x2222222222222222; + y2 = y & (uint64_t)0x4444444444444444; + y3 = y & (uint64_t)0x8888888888888888; + z0 = (x0 * y0) ^ (x1 * y3) ^ (x2 * y2) ^ (x3 * y1); + z1 = (x0 * y1) ^ (x1 * y0) ^ (x2 * y3) ^ (x3 * y2); + z2 = (x0 * y2) ^ (x1 * y1) ^ (x2 * y0) ^ (x3 * y3); + z3 = (x0 * y3) ^ (x1 * y2) ^ (x2 * y1) ^ (x3 * y0); + z0 &= (uint64_t)0x1111111111111111; + z1 &= (uint64_t)0x2222222222222222; + z2 &= (uint64_t)0x4444444444444444; + z3 &= (uint64_t)0x8888888888888888; + return z0 | z1 | z2 | z3; +} + +static uint64_t +rev64(uint64_t x) +{ +#define RMS(m, s) do { \ + x = ((x & (uint64_t)(m)) << (s)) \ + | ((x >> (s)) & (uint64_t)(m)); \ + } while (0) + + RMS(0x5555555555555555, 1); + RMS(0x3333333333333333, 2); + RMS(0x0F0F0F0F0F0F0F0F, 4); + RMS(0x00FF00FF00FF00FF, 8); + RMS(0x0000FFFF0000FFFF, 16); + return (x << 32) | (x >> 32); + +#undef RMS +} + +/* see bearssl_ghash.h */ +void +br_ghash_ctmul64(void *y, const void *h, const void *data, size_t len) +{ + const unsigned char *buf, *hb; + unsigned char *yb; + uint64_t y0, y1; + uint64_t h0, h1, h2, h0r, h1r, h2r; + + buf = data; + yb = y; + hb = h; + y1 = br_dec64be(yb); + y0 = br_dec64be(yb + 8); + h1 = br_dec64be(hb); + h0 = br_dec64be(hb + 8); + h0r = rev64(h0); + h1r = rev64(h1); + h2 = h0 ^ h1; + h2r = h0r ^ h1r; + while (len > 0) { + const unsigned char *src; + unsigned char tmp[16]; + uint64_t y0r, y1r, y2, y2r; + uint64_t z0, z1, z2, z0h, z1h, z2h; + uint64_t v0, v1, v2, v3; + + if (len >= 16) { + src = buf; + buf += 16; + len -= 16; + } else { + memcpy(tmp, buf, len); + memset(tmp + len, 0, (sizeof tmp) - len); + src = tmp; + len = 0; + } + y1 ^= br_dec64be(src); + y0 ^= br_dec64be(src + 8); + + y0r = rev64(y0); + y1r = rev64(y1); + y2 = y0 ^ y1; + y2r = y0r ^ y1r; + + z0 = bmul64(y0, h0); + z1 = bmul64(y1, h1); + z2 = bmul64(y2, h2); + z0h = bmul64(y0r, h0r); + z1h = bmul64(y1r, h1r); + z2h = bmul64(y2r, h2r); + z2 ^= z0 ^ z1; + z2h ^= z0h ^ z1h; + z0h = rev64(z0h) >> 1; + z1h = rev64(z1h) >> 1; + z2h = rev64(z2h) >> 1; + + v0 = z0; + v1 = z0h ^ z2; + v2 = z1 ^ z2h; + v3 = z1h; + + v3 = (v3 << 1) | (v2 >> 63); + v2 = (v2 << 1) | (v1 >> 63); + v1 = (v1 << 1) | (v0 >> 63); + v0 = (v0 << 1); + + v2 ^= v0 ^ (v0 >> 1) ^ (v0 >> 2) ^ (v0 >> 7); + v1 ^= (v0 << 63) ^ (v0 << 62) ^ (v0 << 57); + v3 ^= v1 ^ (v1 >> 1) ^ (v1 >> 2) ^ (v1 >> 7); + v2 ^= (v1 << 63) ^ (v1 << 62) ^ (v1 << 57); + + y0 = v2; + y1 = v3; + } + + br_enc64be(yb, y1); + br_enc64be(yb + 8, y0); +} |