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Diffstat (limited to 'lib/libmd/sha256c.c')
| -rw-r--r-- | lib/libmd/sha256c.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/lib/libmd/sha256c.c b/lib/libmd/sha256c.c new file mode 100644 index 0000000..d94e871 --- /dev/null +++ b/lib/libmd/sha256c.c @@ -0,0 +1,299 @@ +/*- + * Copyright 2005 Colin Percival + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 THE AUTHOR OR CONTRIBUTORS 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/endian.h> +#include <sys/types.h> + +#include <string.h> + +#include "sha256.h" + +#if BYTE_ORDER == BIG_ENDIAN + +/* Copy a vector of big-endian uint32_t into a vector of bytes */ +#define be32enc_vect(dst, src, len) \ + memcpy((void *)dst, (const void *)src, (size_t)len) + +/* Copy a vector of bytes into a vector of big-endian uint32_t */ +#define be32dec_vect(dst, src, len) \ + memcpy((void *)dst, (const void *)src, (size_t)len) + +#else /* BYTE_ORDER != BIG_ENDIAN */ + +/* + * Encode a length len/4 vector of (uint32_t) into a length len vector of + * (unsigned char) in big-endian form. Assumes len is a multiple of 4. + */ +static void +be32enc_vect(unsigned char *dst, const uint32_t *src, size_t len) +{ + size_t i; + + for (i = 0; i < len / 4; i++) + be32enc(dst + i * 4, src[i]); +} + +/* + * Decode a big-endian length len vector of (unsigned char) into a length + * len/4 vector of (uint32_t). Assumes len is a multiple of 4. + */ +static void +be32dec_vect(uint32_t *dst, const unsigned char *src, size_t len) +{ + size_t i; + + for (i = 0; i < len / 4; i++) + dst[i] = be32dec(src + i * 4); +} + +#endif /* BYTE_ORDER != BIG_ENDIAN */ + +/* Elementary functions used by SHA256 */ +#define Ch(x, y, z) ((x & (y ^ z)) ^ z) +#define Maj(x, y, z) ((x & (y | z)) | (y & z)) +#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)) +#define S1(x) (ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25)) +#define s0(x) (ROTR(x, 7) ^ ROTR(x, 18) ^ SHR(x, 3)) +#define s1(x) (ROTR(x, 17) ^ ROTR(x, 19) ^ SHR(x, 10)) + +/* SHA256 round function */ +#define RND(a, b, c, d, e, f, g, h, k) \ + t0 = h + S1(e) + Ch(e, f, g) + k; \ + t1 = S0(a) + Maj(a, b, c); \ + d += t0; \ + h = t0 + t1; + +/* Adjusted round function for rotating state */ +#define RNDr(S, W, i, k) \ + RND(S[(64 - i) % 8], S[(65 - i) % 8], \ + S[(66 - i) % 8], S[(67 - i) % 8], \ + S[(68 - i) % 8], S[(69 - i) % 8], \ + S[(70 - i) % 8], S[(71 - i) % 8], \ + W[i] + k) + +/* + * SHA256 block compression function. The 256-bit state is transformed via + * the 512-bit input block to produce a new state. + */ +static void +SHA256_Transform(uint32_t * state, const unsigned char block[64]) +{ + uint32_t W[64]; + uint32_t S[8]; + uint32_t t0, t1; + int i; + + /* 1. Prepare message schedule W. */ + be32dec_vect(W, block, 64); + for (i = 16; i < 64; i++) + W[i] = s1(W[i - 2]) + W[i - 7] + s0(W[i - 15]) + W[i - 16]; + + /* 2. Initialize working variables. */ + memcpy(S, state, 32); + + /* 3. Mix. */ + RNDr(S, W, 0, 0x428a2f98); + RNDr(S, W, 1, 0x71374491); + RNDr(S, W, 2, 0xb5c0fbcf); + RNDr(S, W, 3, 0xe9b5dba5); + RNDr(S, W, 4, 0x3956c25b); + RNDr(S, W, 5, 0x59f111f1); + RNDr(S, W, 6, 0x923f82a4); + RNDr(S, W, 7, 0xab1c5ed5); + RNDr(S, W, 8, 0xd807aa98); + RNDr(S, W, 9, 0x12835b01); + RNDr(S, W, 10, 0x243185be); + RNDr(S, W, 11, 0x550c7dc3); + RNDr(S, W, 12, 0x72be5d74); + RNDr(S, W, 13, 0x80deb1fe); + RNDr(S, W, 14, 0x9bdc06a7); + RNDr(S, W, 15, 0xc19bf174); + RNDr(S, W, 16, 0xe49b69c1); + RNDr(S, W, 17, 0xefbe4786); + RNDr(S, W, 18, 0x0fc19dc6); + RNDr(S, W, 19, 0x240ca1cc); + RNDr(S, W, 20, 0x2de92c6f); + RNDr(S, W, 21, 0x4a7484aa); + RNDr(S, W, 22, 0x5cb0a9dc); + RNDr(S, W, 23, 0x76f988da); + RNDr(S, W, 24, 0x983e5152); + RNDr(S, W, 25, 0xa831c66d); + RNDr(S, W, 26, 0xb00327c8); + RNDr(S, W, 27, 0xbf597fc7); + RNDr(S, W, 28, 0xc6e00bf3); + RNDr(S, W, 29, 0xd5a79147); + RNDr(S, W, 30, 0x06ca6351); + RNDr(S, W, 31, 0x14292967); + RNDr(S, W, 32, 0x27b70a85); + RNDr(S, W, 33, 0x2e1b2138); + RNDr(S, W, 34, 0x4d2c6dfc); + RNDr(S, W, 35, 0x53380d13); + RNDr(S, W, 36, 0x650a7354); + RNDr(S, W, 37, 0x766a0abb); + RNDr(S, W, 38, 0x81c2c92e); + RNDr(S, W, 39, 0x92722c85); + RNDr(S, W, 40, 0xa2bfe8a1); + RNDr(S, W, 41, 0xa81a664b); + RNDr(S, W, 42, 0xc24b8b70); + RNDr(S, W, 43, 0xc76c51a3); + RNDr(S, W, 44, 0xd192e819); + RNDr(S, W, 45, 0xd6990624); + RNDr(S, W, 46, 0xf40e3585); + RNDr(S, W, 47, 0x106aa070); + RNDr(S, W, 48, 0x19a4c116); + RNDr(S, W, 49, 0x1e376c08); + RNDr(S, W, 50, 0x2748774c); + RNDr(S, W, 51, 0x34b0bcb5); + RNDr(S, W, 52, 0x391c0cb3); + RNDr(S, W, 53, 0x4ed8aa4a); + RNDr(S, W, 54, 0x5b9cca4f); + RNDr(S, W, 55, 0x682e6ff3); + RNDr(S, W, 56, 0x748f82ee); + RNDr(S, W, 57, 0x78a5636f); + RNDr(S, W, 58, 0x84c87814); + RNDr(S, W, 59, 0x8cc70208); + RNDr(S, W, 60, 0x90befffa); + RNDr(S, W, 61, 0xa4506ceb); + RNDr(S, W, 62, 0xbef9a3f7); + RNDr(S, W, 63, 0xc67178f2); + + /* 4. Mix local working variables into global state */ + for (i = 0; i < 8; i++) + state[i] += S[i]; +} + +static unsigned char PAD[64] = { + 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 +}; + +/* Add padding and terminating bit-count. */ +static void +SHA256_Pad(SHA256_CTX * ctx) +{ + unsigned char len[8]; + uint32_t r, plen; + + /* + * Convert length to a vector of bytes -- we do this now rather + * than later because the length will change after we pad. + */ + be32enc_vect(len, ctx->count, 8); + + /* Add 1--64 bytes so that the resulting length is 56 mod 64 */ + r = (ctx->count[1] >> 3) & 0x3f; + plen = (r < 56) ? (56 - r) : (120 - r); + SHA256_Update(ctx, PAD, (size_t)plen); + + /* Add the terminating bit-count */ + SHA256_Update(ctx, len, 8); +} + +/* SHA-256 initialization. Begins a SHA-256 operation. */ +void +SHA256_Init(SHA256_CTX * ctx) +{ + + /* Zero bits processed so far */ + ctx->count[0] = ctx->count[1] = 0; + + /* Magic initialization constants */ + ctx->state[0] = 0x6A09E667; + ctx->state[1] = 0xBB67AE85; + ctx->state[2] = 0x3C6EF372; + ctx->state[3] = 0xA54FF53A; + ctx->state[4] = 0x510E527F; + ctx->state[5] = 0x9B05688C; + ctx->state[6] = 0x1F83D9AB; + ctx->state[7] = 0x5BE0CD19; +} + +/* Add bytes into the hash */ +void +SHA256_Update(SHA256_CTX * ctx, const unsigned char *src, size_t len) +{ + uint32_t bitlen[2]; + uint32_t r; + + /* Number of bytes left in the buffer from previous updates */ + r = (ctx->count[1] >> 3) & 0x3f; + + /* Convert the length into a number of bits */ + bitlen[1] = ((uint32_t)len) << 3; + bitlen[0] = (uint32_t)(len >> 29); + + /* Update number of bits */ + if ((ctx->count[1] += bitlen[1]) < bitlen[1]) + ctx->count[0]++; + ctx->count[0] += bitlen[0]; + + /* Handle the case where we don't need to perform any transforms */ + if (len < 64 - r) { + memcpy(&ctx->buf[r], src, len); + return; + } + + /* Finish the current block */ + memcpy(&ctx->buf[r], src, 64 - r); + SHA256_Transform(ctx->state, ctx->buf); + src += 64 - r; + len -= 64 - r; + + /* Perform complete blocks */ + while (len >= 64) { + SHA256_Transform(ctx->state, src); + src += 64; + len -= 64; + } + + /* Copy left over data into buffer */ + memcpy(ctx->buf, src, len); +} + +/* + * SHA-256 finalization. Pads the input data, exports the hash value, + * and clears the context state. + */ +void +SHA256_Final(unsigned char digest[32], SHA256_CTX * ctx) +{ + + /* Add padding */ + SHA256_Pad(ctx); + + /* Write the hash */ + be32enc_vect(digest, ctx->state, 32); + + /* Clear the context state */ + memset((void *)ctx, 0, sizeof(*ctx)); +} |
