/* md5.c - an implementation of the MD5 algorithm, based on RFC 1321. * * Copyright: 2007-2012 Aleksey Kravchenko * * 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. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. Use this program at your own risk! */ #include #include "byte_order.h" #include "md5.h" /** * Initialize context before calculaing hash. * * @param ctx context to initialize */ void rhash_md5_init(md5_ctx *ctx) { ctx->length = 0; /* initialize state */ ctx->hash[0] = 0x67452301; ctx->hash[1] = 0xefcdab89; ctx->hash[2] = 0x98badcfe; ctx->hash[3] = 0x10325476; } /* First, define four auxiliary functions that each take as input * three 32-bit words and returns a 32-bit word.*/ /* F(x,y,z) = ((y XOR z) AND x) XOR z - is faster then original version */ #define MD5_F(x, y, z) ((((y) ^ (z)) & (x)) ^ (z)) #define MD5_G(x, y, z) (((x) & (z)) | ((y) & (~z))) #define MD5_H(x, y, z) ((x) ^ (y) ^ (z)) #define MD5_I(x, y, z) ((y) ^ ((x) | (~z))) /* transformations for rounds 1, 2, 3, and 4. */ #define MD5_ROUND1(a, b, c, d, x, s, ac) { \ (a) += MD5_F((b), (c), (d)) + (x) + (ac); \ (a) = ROTL32((a), (s)); \ (a) += (b); \ } #define MD5_ROUND2(a, b, c, d, x, s, ac) { \ (a) += MD5_G((b), (c), (d)) + (x) + (ac); \ (a) = ROTL32((a), (s)); \ (a) += (b); \ } #define MD5_ROUND3(a, b, c, d, x, s, ac) { \ (a) += MD5_H((b), (c), (d)) + (x) + (ac); \ (a) = ROTL32((a), (s)); \ (a) += (b); \ } #define MD5_ROUND4(a, b, c, d, x, s, ac) { \ (a) += MD5_I((b), (c), (d)) + (x) + (ac); \ (a) = ROTL32((a), (s)); \ (a) += (b); \ } /** * The core transformation. Process a 512-bit block. * The function has been taken from RFC 1321 with little changes. * * @param state algorithm state * @param x the message block to process */ static void rhash_md5_process_block(unsigned state[4], const unsigned* x) { register unsigned a, b, c, d; a = state[0]; b = state[1]; c = state[2]; d = state[3]; MD5_ROUND1(a, b, c, d, x[ 0], 7, 0xd76aa478); MD5_ROUND1(d, a, b, c, x[ 1], 12, 0xe8c7b756); MD5_ROUND1(c, d, a, b, x[ 2], 17, 0x242070db); MD5_ROUND1(b, c, d, a, x[ 3], 22, 0xc1bdceee); MD5_ROUND1(a, b, c, d, x[ 4], 7, 0xf57c0faf); MD5_ROUND1(d, a, b, c, x[ 5], 12, 0x4787c62a); MD5_ROUND1(c, d, a, b, x[ 6], 17, 0xa8304613); MD5_ROUND1(b, c, d, a, x[ 7], 22, 0xfd469501); MD5_ROUND1(a, b, c, d, x[ 8], 7, 0x698098d8); MD5_ROUND1(d, a, b, c, x[ 9], 12, 0x8b44f7af); MD5_ROUND1(c, d, a, b, x[10], 17, 0xffff5bb1); MD5_ROUND1(b, c, d, a, x[11], 22, 0x895cd7be); MD5_ROUND1(a, b, c, d, x[12], 7, 0x6b901122); MD5_ROUND1(d, a, b, c, x[13], 12, 0xfd987193); MD5_ROUND1(c, d, a, b, x[14], 17, 0xa679438e); MD5_ROUND1(b, c, d, a, x[15], 22, 0x49b40821); MD5_ROUND2(a, b, c, d, x[ 1], 5, 0xf61e2562); MD5_ROUND2(d, a, b, c, x[ 6], 9, 0xc040b340); MD5_ROUND2(c, d, a, b, x[11], 14, 0x265e5a51); MD5_ROUND2(b, c, d, a, x[ 0], 20, 0xe9b6c7aa); MD5_ROUND2(a, b, c, d, x[ 5], 5, 0xd62f105d); MD5_ROUND2(d, a, b, c, x[10], 9, 0x2441453); MD5_ROUND2(c, d, a, b, x[15], 14, 0xd8a1e681); MD5_ROUND2(b, c, d, a, x[ 4], 20, 0xe7d3fbc8); MD5_ROUND2(a, b, c, d, x[ 9], 5, 0x21e1cde6); MD5_ROUND2(d, a, b, c, x[14], 9, 0xc33707d6); MD5_ROUND2(c, d, a, b, x[ 3], 14, 0xf4d50d87); MD5_ROUND2(b, c, d, a, x[ 8], 20, 0x455a14ed); MD5_ROUND2(a, b, c, d, x[13], 5, 0xa9e3e905); MD5_ROUND2(d, a, b, c, x[ 2], 9, 0xfcefa3f8); MD5_ROUND2(c, d, a, b, x[ 7], 14, 0x676f02d9); MD5_ROUND2(b, c, d, a, x[12], 20, 0x8d2a4c8a); MD5_ROUND3(a, b, c, d, x[ 5], 4, 0xfffa3942); MD5_ROUND3(d, a, b, c, x[ 8], 11, 0x8771f681); MD5_ROUND3(c, d, a, b, x[11], 16, 0x6d9d6122); MD5_ROUND3(b, c, d, a, x[14], 23, 0xfde5380c); MD5_ROUND3(a, b, c, d, x[ 1], 4, 0xa4beea44); MD5_ROUND3(d, a, b, c, x[ 4], 11, 0x4bdecfa9); MD5_ROUND3(c, d, a, b, x[ 7], 16, 0xf6bb4b60); MD5_ROUND3(b, c, d, a, x[10], 23, 0xbebfbc70); MD5_ROUND3(a, b, c, d, x[13], 4, 0x289b7ec6); MD5_ROUND3(d, a, b, c, x[ 0], 11, 0xeaa127fa); MD5_ROUND3(c, d, a, b, x[ 3], 16, 0xd4ef3085); MD5_ROUND3(b, c, d, a, x[ 6], 23, 0x4881d05); MD5_ROUND3(a, b, c, d, x[ 9], 4, 0xd9d4d039); MD5_ROUND3(d, a, b, c, x[12], 11, 0xe6db99e5); MD5_ROUND3(c, d, a, b, x[15], 16, 0x1fa27cf8); MD5_ROUND3(b, c, d, a, x[ 2], 23, 0xc4ac5665); MD5_ROUND4(a, b, c, d, x[ 0], 6, 0xf4292244); MD5_ROUND4(d, a, b, c, x[ 7], 10, 0x432aff97); MD5_ROUND4(c, d, a, b, x[14], 15, 0xab9423a7); MD5_ROUND4(b, c, d, a, x[ 5], 21, 0xfc93a039); MD5_ROUND4(a, b, c, d, x[12], 6, 0x655b59c3); MD5_ROUND4(d, a, b, c, x[ 3], 10, 0x8f0ccc92); MD5_ROUND4(c, d, a, b, x[10], 15, 0xffeff47d); MD5_ROUND4(b, c, d, a, x[ 1], 21, 0x85845dd1); MD5_ROUND4(a, b, c, d, x[ 8], 6, 0x6fa87e4f); MD5_ROUND4(d, a, b, c, x[15], 10, 0xfe2ce6e0); MD5_ROUND4(c, d, a, b, x[ 6], 15, 0xa3014314); MD5_ROUND4(b, c, d, a, x[13], 21, 0x4e0811a1); MD5_ROUND4(a, b, c, d, x[ 4], 6, 0xf7537e82); MD5_ROUND4(d, a, b, c, x[11], 10, 0xbd3af235); MD5_ROUND4(c, d, a, b, x[ 2], 15, 0x2ad7d2bb); MD5_ROUND4(b, c, d, a, x[ 9], 21, 0xeb86d391); state[0] += a; state[1] += b; state[2] += c; state[3] += d; } /** * Calculate message hash. * Can be called repeatedly with chunks of the message to be hashed. * * @param ctx the algorithm context containing current hashing state * @param msg message chunk * @param size length of the message chunk */ void rhash_md5_update(md5_ctx *ctx, const unsigned char* msg, size_t size) { unsigned index = (unsigned)ctx->length & 63; ctx->length += size; /* fill partial block */ if (index) { unsigned left = md5_block_size - index; le32_copy((char*)ctx->message, index, msg, (size < left ? size : left)); if (size < left) return; /* process partial block */ rhash_md5_process_block(ctx->hash, ctx->message); msg += left; size -= left; } while (size >= md5_block_size) { unsigned* aligned_message_block; if (IS_LITTLE_ENDIAN && IS_ALIGNED_32(msg)) { /* the most common case is processing a 32-bit aligned message on a little-endian CPU without copying it */ aligned_message_block = (unsigned*)msg; } else { le32_copy(ctx->message, 0, msg, md5_block_size); aligned_message_block = ctx->message; } rhash_md5_process_block(ctx->hash, aligned_message_block); msg += md5_block_size; size -= md5_block_size; } if (size) { /* save leftovers */ le32_copy(ctx->message, 0, msg, size); } } /** * Store calculated hash into the given array. * * @param ctx the algorithm context containing current hashing state * @param result calculated hash in binary form */ void rhash_md5_final(md5_ctx *ctx, unsigned char* result) { unsigned index = ((unsigned)ctx->length & 63) >> 2; unsigned shift = ((unsigned)ctx->length & 3) * 8; /* pad message and run for last block */ /* append the byte 0x80 to the message */ ctx->message[index] &= ~(0xFFFFFFFFu << shift); ctx->message[index++] ^= 0x80u << shift; /* if no room left in the message to store 64-bit message length */ if (index > 14) { /* then fill the rest with zeros and process it */ while (index < 16) { ctx->message[index++] = 0; } rhash_md5_process_block(ctx->hash, ctx->message); index = 0; } while (index < 14) { ctx->message[index++] = 0; } ctx->message[14] = (unsigned)(ctx->length << 3); ctx->message[15] = (unsigned)(ctx->length >> 29); rhash_md5_process_block(ctx->hash, ctx->message); if (result) le32_copy(result, 0, &ctx->hash, 16); }