md5.c (8439B)
1 /* 2 * This is an OpenSSL-compatible implementation of the RSA Data Security, Inc. 3 * MD5 Message-Digest Algorithm (RFC 1321). 4 * 5 * Homepage: 6 * http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5 7 * 8 * Author: 9 * Alexander Peslyak, better known as Solar Designer <solar at openwall.com> 10 * 11 * This software was written by Alexander Peslyak in 2001. No copyright is 12 * claimed, and the software is hereby placed in the public domain. 13 * In case this attempt to disclaim copyright and place the software in the 14 * public domain is deemed null and void, then the software is 15 * Copyright (c) 2001 Alexander Peslyak and it is hereby released to the 16 * general public under the following terms: 17 * 18 * Redistribution and use in source and binary forms, with or without 19 * modification, are permitted. 20 * 21 * There's ABSOLUTELY NO WARRANTY, express or implied. 22 * 23 * (This is a heavily cut-down "BSD license".) 24 * 25 * This differs from Colin Plumb's older public domain implementation in that 26 * no exactly 32-bit integer data type is required (any 32-bit or wider 27 * unsigned integer data type will do), there's no compile-time endianness 28 * configuration, and the function prototypes match OpenSSL's. No code from 29 * Colin Plumb's implementation has been reused; this comment merely compares 30 * the properties of the two independent implementations. 31 * 32 * The primary goals of this implementation are portability and ease of use. 33 * It is meant to be fast, but not as fast as possible. Some known 34 * optimizations are not included to reduce source code size and avoid 35 * compile-time configuration. 36 */ 37 38 #ifndef HAVE_OPENSSL 39 40 #include <string.h> 41 42 #include "md5.h" 43 44 /* 45 * The basic MD5 functions. 46 * 47 * F and G are optimized compared to their RFC 1321 definitions for 48 * architectures that lack an AND-NOT instruction, just like in Colin Plumb's 49 * implementation. 50 */ 51 #define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z)))) 52 #define G(x, y, z) ((y) ^ ((z) & ((x) ^ (y)))) 53 #define H(x, y, z) ((x) ^ (y) ^ (z)) 54 #define I(x, y, z) ((y) ^ ((x) | ~(z))) 55 56 /* 57 * The MD5 transformation for all four rounds. 58 */ 59 #define STEP(f, a, b, c, d, x, t, s) \ 60 (a) += f((b), (c), (d)) + (x) + (t); \ 61 (a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \ 62 (a) += (b); 63 64 /* 65 * SET reads 4 input bytes in little-endian byte order and stores them 66 * in a properly aligned word in host byte order. 67 * 68 * The check for little-endian architectures that tolerate unaligned 69 * memory accesses is just an optimization. Nothing will break if it 70 * doesn't work. 71 */ 72 #if defined(__i386__) || defined(__x86_64__) || defined(__vax__) 73 #define SET(n) \ 74 (*(MD5_u32plus *)&ptr[(n) * 4]) 75 #define GET(n) \ 76 SET(n) 77 #else 78 #define SET(n) \ 79 (ctx->block[(n)] = \ 80 (MD5_u32plus)ptr[(n) * 4] | \ 81 ((MD5_u32plus)ptr[(n) * 4 + 1] << 8) | \ 82 ((MD5_u32plus)ptr[(n) * 4 + 2] << 16) | \ 83 ((MD5_u32plus)ptr[(n) * 4 + 3] << 24)) 84 #define GET(n) \ 85 (ctx->block[(n)]) 86 #endif 87 88 /* 89 * This processes one or more 64-byte data blocks, but does NOT update 90 * the bit counters. There are no alignment requirements. 91 */ 92 static void *body(MD5_CTX *ctx, void *data, unsigned long size) 93 { 94 unsigned char *ptr; 95 MD5_u32plus a, b, c, d; 96 MD5_u32plus saved_a, saved_b, saved_c, saved_d; 97 98 ptr = (unsigned char *)data; 99 100 a = ctx->a; 101 b = ctx->b; 102 c = ctx->c; 103 d = ctx->d; 104 105 do { 106 saved_a = a; 107 saved_b = b; 108 saved_c = c; 109 saved_d = d; 110 111 /* Round 1 */ 112 STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7) 113 STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12) 114 STEP(F, c, d, a, b, SET(2), 0x242070db, 17) 115 STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22) 116 STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7) 117 STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12) 118 STEP(F, c, d, a, b, SET(6), 0xa8304613, 17) 119 STEP(F, b, c, d, a, SET(7), 0xfd469501, 22) 120 STEP(F, a, b, c, d, SET(8), 0x698098d8, 7) 121 STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12) 122 STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17) 123 STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22) 124 STEP(F, a, b, c, d, SET(12), 0x6b901122, 7) 125 STEP(F, d, a, b, c, SET(13), 0xfd987193, 12) 126 STEP(F, c, d, a, b, SET(14), 0xa679438e, 17) 127 STEP(F, b, c, d, a, SET(15), 0x49b40821, 22) 128 129 /* Round 2 */ 130 STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5) 131 STEP(G, d, a, b, c, GET(6), 0xc040b340, 9) 132 STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14) 133 STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20) 134 STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5) 135 STEP(G, d, a, b, c, GET(10), 0x02441453, 9) 136 STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14) 137 STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20) 138 STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5) 139 STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9) 140 STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14) 141 STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20) 142 STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5) 143 STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9) 144 STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14) 145 STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20) 146 147 /* Round 3 */ 148 STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4) 149 STEP(H, d, a, b, c, GET(8), 0x8771f681, 11) 150 STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16) 151 STEP(H, b, c, d, a, GET(14), 0xfde5380c, 23) 152 STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4) 153 STEP(H, d, a, b, c, GET(4), 0x4bdecfa9, 11) 154 STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16) 155 STEP(H, b, c, d, a, GET(10), 0xbebfbc70, 23) 156 STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4) 157 STEP(H, d, a, b, c, GET(0), 0xeaa127fa, 11) 158 STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16) 159 STEP(H, b, c, d, a, GET(6), 0x04881d05, 23) 160 STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4) 161 STEP(H, d, a, b, c, GET(12), 0xe6db99e5, 11) 162 STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16) 163 STEP(H, b, c, d, a, GET(2), 0xc4ac5665, 23) 164 165 /* Round 4 */ 166 STEP(I, a, b, c, d, GET(0), 0xf4292244, 6) 167 STEP(I, d, a, b, c, GET(7), 0x432aff97, 10) 168 STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15) 169 STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21) 170 STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6) 171 STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10) 172 STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15) 173 STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21) 174 STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6) 175 STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10) 176 STEP(I, c, d, a, b, GET(6), 0xa3014314, 15) 177 STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21) 178 STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6) 179 STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10) 180 STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15) 181 STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21) 182 183 a += saved_a; 184 b += saved_b; 185 c += saved_c; 186 d += saved_d; 187 188 ptr += 64; 189 } while (size -= 64); 190 191 ctx->a = a; 192 ctx->b = b; 193 ctx->c = c; 194 ctx->d = d; 195 196 return ptr; 197 } 198 199 void MD5_Init(MD5_CTX *ctx) 200 { 201 ctx->a = 0x67452301; 202 ctx->b = 0xefcdab89; 203 ctx->c = 0x98badcfe; 204 ctx->d = 0x10325476; 205 206 ctx->lo = 0; 207 ctx->hi = 0; 208 } 209 210 void MD5_Update(MD5_CTX *ctx, void *data, unsigned long size) 211 { 212 MD5_u32plus saved_lo; 213 unsigned long used, free; 214 215 saved_lo = ctx->lo; 216 if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo) 217 ctx->hi++; 218 ctx->hi += size >> 29; 219 220 used = saved_lo & 0x3f; 221 222 if (used) { 223 free = 64 - used; 224 225 if (size < free) { 226 memcpy(&ctx->buffer[used], data, size); 227 return; 228 } 229 230 memcpy(&ctx->buffer[used], data, free); 231 data = (unsigned char *)data + free; 232 size -= free; 233 body(ctx, ctx->buffer, 64); 234 } 235 236 if (size >= 64) { 237 data = body(ctx, data, size & ~(unsigned long)0x3f); 238 size &= 0x3f; 239 } 240 241 memcpy(ctx->buffer, data, size); 242 } 243 244 void MD5_Final(unsigned char *result, MD5_CTX *ctx) 245 { 246 unsigned long used, free; 247 248 used = ctx->lo & 0x3f; 249 250 ctx->buffer[used++] = 0x80; 251 252 free = 64 - used; 253 254 if (free < 8) { 255 memset(&ctx->buffer[used], 0, free); 256 body(ctx, ctx->buffer, 64); 257 used = 0; 258 free = 64; 259 } 260 261 memset(&ctx->buffer[used], 0, free - 8); 262 263 ctx->lo <<= 3; 264 ctx->buffer[56] = ctx->lo; 265 ctx->buffer[57] = ctx->lo >> 8; 266 ctx->buffer[58] = ctx->lo >> 16; 267 ctx->buffer[59] = ctx->lo >> 24; 268 ctx->buffer[60] = ctx->hi; 269 ctx->buffer[61] = ctx->hi >> 8; 270 ctx->buffer[62] = ctx->hi >> 16; 271 ctx->buffer[63] = ctx->hi >> 24; 272 273 body(ctx, ctx->buffer, 64); 274 275 result[0] = ctx->a; 276 result[1] = ctx->a >> 8; 277 result[2] = ctx->a >> 16; 278 result[3] = ctx->a >> 24; 279 result[4] = ctx->b; 280 result[5] = ctx->b >> 8; 281 result[6] = ctx->b >> 16; 282 result[7] = ctx->b >> 24; 283 result[8] = ctx->c; 284 result[9] = ctx->c >> 8; 285 result[10] = ctx->c >> 16; 286 result[11] = ctx->c >> 24; 287 result[12] = ctx->d; 288 result[13] = ctx->d >> 8; 289 result[14] = ctx->d >> 16; 290 result[15] = ctx->d >> 24; 291 292 memset(ctx, 0, sizeof(*ctx)); 293 } 294 295 #endif