md5.c (8743B)
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 H2(x, y, z) ((x) ^ ((y) ^ (z))) 55 #define I(x, y, z) ((y) ^ ((x) | ~(z))) 56 57 /* 58 * The MD5 transformation for all four rounds. 59 */ 60 #define STEP(f, a, b, c, d, x, t, s) \ 61 (a) += f((b), (c), (d)) + (x) + (t); \ 62 (a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \ 63 (a) += (b); 64 65 /* 66 * SET reads 4 input bytes in little-endian byte order and stores them in a 67 * properly aligned word in host byte order. 68 * 69 * The check for little-endian architectures that tolerate unaligned memory 70 * accesses is just an optimization. Nothing will break if it fails to detect 71 * a suitable architecture. 72 * 73 * Unfortunately, this optimization may be a C strict aliasing rules violation 74 * if the caller's data buffer has effective type that cannot be aliased by 75 * MD5_u32plus. In practice, this problem may occur if these MD5 routines are 76 * inlined into a calling function, or with future and dangerously advanced 77 * link-time optimizations. For the time being, keeping these MD5 routines in 78 * their own translation unit avoids the problem. 79 */ 80 #if defined(__i386__) || defined(__x86_64__) || defined(__vax__) 81 #define SET(n) \ 82 (*(MD5_u32plus *)&ptr[(n) * 4]) 83 #define GET(n) \ 84 SET(n) 85 #else 86 #define SET(n) \ 87 (ctx->block[(n)] = \ 88 (MD5_u32plus)ptr[(n) * 4] | \ 89 ((MD5_u32plus)ptr[(n) * 4 + 1] << 8) | \ 90 ((MD5_u32plus)ptr[(n) * 4 + 2] << 16) | \ 91 ((MD5_u32plus)ptr[(n) * 4 + 3] << 24)) 92 #define GET(n) \ 93 (ctx->block[(n)]) 94 #endif 95 96 /* 97 * This processes one or more 64-byte data blocks, but does NOT update the bit 98 * counters. There are no alignment requirements. 99 */ 100 static const void *body(MD5_CTX *ctx, const void *data, unsigned long size) 101 { 102 const unsigned char *ptr; 103 MD5_u32plus a, b, c, d; 104 MD5_u32plus saved_a, saved_b, saved_c, saved_d; 105 106 ptr = (const unsigned char *)data; 107 108 a = ctx->a; 109 b = ctx->b; 110 c = ctx->c; 111 d = ctx->d; 112 113 do { 114 saved_a = a; 115 saved_b = b; 116 saved_c = c; 117 saved_d = d; 118 119 /* Round 1 */ 120 STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7) 121 STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12) 122 STEP(F, c, d, a, b, SET(2), 0x242070db, 17) 123 STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22) 124 STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7) 125 STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12) 126 STEP(F, c, d, a, b, SET(6), 0xa8304613, 17) 127 STEP(F, b, c, d, a, SET(7), 0xfd469501, 22) 128 STEP(F, a, b, c, d, SET(8), 0x698098d8, 7) 129 STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12) 130 STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17) 131 STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22) 132 STEP(F, a, b, c, d, SET(12), 0x6b901122, 7) 133 STEP(F, d, a, b, c, SET(13), 0xfd987193, 12) 134 STEP(F, c, d, a, b, SET(14), 0xa679438e, 17) 135 STEP(F, b, c, d, a, SET(15), 0x49b40821, 22) 136 137 /* Round 2 */ 138 STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5) 139 STEP(G, d, a, b, c, GET(6), 0xc040b340, 9) 140 STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14) 141 STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20) 142 STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5) 143 STEP(G, d, a, b, c, GET(10), 0x02441453, 9) 144 STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14) 145 STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20) 146 STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5) 147 STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9) 148 STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14) 149 STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20) 150 STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5) 151 STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9) 152 STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14) 153 STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20) 154 155 /* Round 3 */ 156 STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4) 157 STEP(H2, d, a, b, c, GET(8), 0x8771f681, 11) 158 STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16) 159 STEP(H2, b, c, d, a, GET(14), 0xfde5380c, 23) 160 STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4) 161 STEP(H2, d, a, b, c, GET(4), 0x4bdecfa9, 11) 162 STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16) 163 STEP(H2, b, c, d, a, GET(10), 0xbebfbc70, 23) 164 STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4) 165 STEP(H2, d, a, b, c, GET(0), 0xeaa127fa, 11) 166 STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16) 167 STEP(H2, b, c, d, a, GET(6), 0x04881d05, 23) 168 STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4) 169 STEP(H2, d, a, b, c, GET(12), 0xe6db99e5, 11) 170 STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16) 171 STEP(H2, b, c, d, a, GET(2), 0xc4ac5665, 23) 172 173 /* Round 4 */ 174 STEP(I, a, b, c, d, GET(0), 0xf4292244, 6) 175 STEP(I, d, a, b, c, GET(7), 0x432aff97, 10) 176 STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15) 177 STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21) 178 STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6) 179 STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10) 180 STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15) 181 STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21) 182 STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6) 183 STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10) 184 STEP(I, c, d, a, b, GET(6), 0xa3014314, 15) 185 STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21) 186 STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6) 187 STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10) 188 STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15) 189 STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21) 190 191 a += saved_a; 192 b += saved_b; 193 c += saved_c; 194 d += saved_d; 195 196 ptr += 64; 197 } while (size -= 64); 198 199 ctx->a = a; 200 ctx->b = b; 201 ctx->c = c; 202 ctx->d = d; 203 204 return ptr; 205 } 206 207 void MD5_Init(MD5_CTX *ctx) 208 { 209 ctx->a = 0x67452301; 210 ctx->b = 0xefcdab89; 211 ctx->c = 0x98badcfe; 212 ctx->d = 0x10325476; 213 214 ctx->lo = 0; 215 ctx->hi = 0; 216 } 217 218 void MD5_Update(MD5_CTX *ctx, const void *data, unsigned long size) 219 { 220 MD5_u32plus saved_lo; 221 unsigned long used, available; 222 223 saved_lo = ctx->lo; 224 if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo) 225 ctx->hi++; 226 ctx->hi += size >> 29; 227 228 used = saved_lo & 0x3f; 229 230 if (used) { 231 available = 64 - used; 232 233 if (size < available) { 234 memcpy(&ctx->buffer[used], data, size); 235 return; 236 } 237 238 memcpy(&ctx->buffer[used], data, available); 239 data = (const unsigned char *)data + available; 240 size -= available; 241 body(ctx, ctx->buffer, 64); 242 } 243 244 if (size >= 64) { 245 data = body(ctx, data, size & ~(unsigned long)0x3f); 246 size &= 0x3f; 247 } 248 249 memcpy(ctx->buffer, data, size); 250 } 251 252 #define OUT(dst, src) \ 253 (dst)[0] = (unsigned char)(src); \ 254 (dst)[1] = (unsigned char)((src) >> 8); \ 255 (dst)[2] = (unsigned char)((src) >> 16); \ 256 (dst)[3] = (unsigned char)((src) >> 24); 257 258 void MD5_Final(unsigned char *result, MD5_CTX *ctx) 259 { 260 unsigned long used, available; 261 262 used = ctx->lo & 0x3f; 263 264 ctx->buffer[used++] = 0x80; 265 266 available = 64 - used; 267 268 if (available < 8) { 269 memset(&ctx->buffer[used], 0, available); 270 body(ctx, ctx->buffer, 64); 271 used = 0; 272 available = 64; 273 } 274 275 memset(&ctx->buffer[used], 0, available - 8); 276 277 ctx->lo <<= 3; 278 OUT(&ctx->buffer[56], ctx->lo) 279 OUT(&ctx->buffer[60], ctx->hi) 280 281 body(ctx, ctx->buffer, 64); 282 283 OUT(&result[0], ctx->a) 284 OUT(&result[4], ctx->b) 285 OUT(&result[8], ctx->c) 286 OUT(&result[12], ctx->d) 287 288 memset(ctx, 0, sizeof(*ctx)); 289 } 290 291 #endif