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Diffstat (limited to '')
| -rw-r--r-- | libmincrypt/sha.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/libmincrypt/sha.c b/libmincrypt/sha.c new file mode 100644 index 000000000..5bef32e42 --- /dev/null +++ b/libmincrypt/sha.c @@ -0,0 +1,155 @@ +/* sha.c +** +** Copyright 2013, The Android Open Source Project +** +** Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions are met: +** * Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** * Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in the +** documentation and/or other materials provided with the distribution. +** * Neither the name of Google Inc. nor the names of its contributors may +** be used to endorse or promote products derived from this software +** without specific prior written permission. +** +** THIS SOFTWARE IS PROVIDED BY Google Inc. ``AS IS'' AND ANY EXPRESS OR +** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF +** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO +** EVENT SHALL Google Inc. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, +** PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; +** OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, +** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR +** OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF +** ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + +// Optimized for minimal code size. + +#include "mincrypt/sha.h" + +#include <stdio.h> +#include <string.h> +#include <stdint.h> + +#define rol(bits, value) (((value) << (bits)) | ((value) >> (32 - (bits)))) + +static void SHA1_Transform(SHA_CTX* ctx) { + uint32_t W[80]; + uint32_t A, B, C, D, E; + uint8_t* p = ctx->buf; + int t; + + for(t = 0; t < 16; ++t) { + uint32_t tmp = *p++ << 24; + tmp |= *p++ << 16; + tmp |= *p++ << 8; + tmp |= *p++; + W[t] = tmp; + } + + for(; t < 80; t++) { + W[t] = rol(1,W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16]); + } + + A = ctx->state[0]; + B = ctx->state[1]; + C = ctx->state[2]; + D = ctx->state[3]; + E = ctx->state[4]; + + for(t = 0; t < 80; t++) { + uint32_t tmp = rol(5,A) + E + W[t]; + + if (t < 20) + tmp += (D^(B&(C^D))) + 0x5A827999; + else if ( t < 40) + tmp += (B^C^D) + 0x6ED9EBA1; + else if ( t < 60) + tmp += ((B&C)|(D&(B|C))) + 0x8F1BBCDC; + else + tmp += (B^C^D) + 0xCA62C1D6; + + E = D; + D = C; + C = rol(30,B); + B = A; + A = tmp; + } + + ctx->state[0] += A; + ctx->state[1] += B; + ctx->state[2] += C; + ctx->state[3] += D; + ctx->state[4] += E; +} + +static const HASH_VTAB SHA_VTAB = { + SHA_init, + SHA_update, + SHA_final, + SHA_hash, + SHA_DIGEST_SIZE +}; + +void SHA_init(SHA_CTX* ctx) { + ctx->f = &SHA_VTAB; + ctx->state[0] = 0x67452301; + ctx->state[1] = 0xEFCDAB89; + ctx->state[2] = 0x98BADCFE; + ctx->state[3] = 0x10325476; + ctx->state[4] = 0xC3D2E1F0; + ctx->count = 0; +} + + +void SHA_update(SHA_CTX* ctx, const void* data, int len) { + int i = (int) (ctx->count & 63); + const uint8_t* p = (const uint8_t*)data; + + ctx->count += len; + + while (len--) { + ctx->buf[i++] = *p++; + if (i == 64) { + SHA1_Transform(ctx); + i = 0; + } + } +} + + +const uint8_t* SHA_final(SHA_CTX* ctx) { + uint8_t *p = ctx->buf; + uint64_t cnt = ctx->count * 8; + int i; + + SHA_update(ctx, (uint8_t*)"\x80", 1); + while ((ctx->count & 63) != 56) { + SHA_update(ctx, (uint8_t*)"\0", 1); + } + for (i = 0; i < 8; ++i) { + uint8_t tmp = (uint8_t) (cnt >> ((7 - i) * 8)); + SHA_update(ctx, &tmp, 1); + } + + for (i = 0; i < 5; i++) { + uint32_t tmp = ctx->state[i]; + *p++ = tmp >> 24; + *p++ = tmp >> 16; + *p++ = tmp >> 8; + *p++ = tmp >> 0; + } + + return ctx->buf; +} + +/* Convenience function */ +const uint8_t* SHA_hash(const void* data, int len, uint8_t* digest) { + SHA_CTX ctx; + SHA_init(&ctx); + SHA_update(&ctx, data, len); + memcpy(digest, SHA_final(&ctx), SHA_DIGEST_SIZE); + return digest; +} |