1 /* 2 * MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm 3 * 4 * Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All 5 * rights reserved. 6 * 7 * License to copy and use this software is granted provided that it 8 * is identified as the "RSA Data Security, Inc. MD5 Message-Digest 9 * Algorithm" in all material mentioning or referencing this software 10 * or this function. 11 * 12 * License is also granted to make and use derivative works provided 13 * that such works are identified as "derived from the RSA Data 14 * Security, Inc. MD5 Message-Digest Algorithm" in all material 15 * mentioning or referencing the derived work. 16 * 17 * RSA Data Security, Inc. makes no representations concerning either 18 * the merchantability of this software or the suitability of this 19 * software for any particular purpose. It is provided "as is" 20 * without express or implied warranty of any kind. 21 * 22 * These notices must be retained in any copies of any part of this 23 * documentation and/or software. 24 * 25 * This code is the same as the code published by RSA Inc. It has been 26 * edited for clarity and style only. 27 */ 28 29 #include <sys/types.h> 30 #include <string.h> 31 32 #include "./md5.h" 33 34 static void MD5Transform(unsigned int [4], const unsigned char [64]); 35 36 #if (BYTE_ORDER == LITTLE_ENDIAN) 37 #define Encode memcpy 38 #define Decode memcpy 39 #else 40 41 /* 42 * OS X doesn't have le32toh() or htole32() 43 */ 44 #ifdef __APPLE__ 45 #include <libkern/OSByteOrder.h> 46 #define le32toh(x) OSSwapLittleToHostInt32(x) 47 #define htole32(x) OSSwapHostToLittleInt32(x) 48 #endif 49 50 /* 51 * Encodes input (unsigned int) into output (unsigned char). Assumes len is 52 * a multiple of 4. 53 */ 54 55 static void 56 Encode (unsigned char *output, unsigned int *input, unsigned int len) 57 { 58 unsigned int i; 59 unsigned int *op = (unsigned int *)output; 60 61 for (i = 0; i < len / 4; i++) 62 op[i] = htole32(input[i]); 63 } 64 65 /* 66 * Decodes input (unsigned char) into output (unsigned int). Assumes len is 67 * a multiple of 4. 68 */ 69 70 static void 71 Decode (unsigned int *output, const unsigned char *input, unsigned int len) 72 { 73 unsigned int i; 74 const unsigned int *ip = (const unsigned int *)input; 75 76 for (i = 0; i < len / 4; i++) 77 output[i] = le32toh(ip[i]); 78 } 79 #endif 80 81 static unsigned char PADDING[64] = { 82 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 83 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 84 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 85 }; 86 87 /* F, G, H and I are basic MD5 functions. */ 88 #define F(x, y, z) (((x) & (y)) | ((~x) & (z))) 89 #define G(x, y, z) (((x) & (z)) | ((y) & (~z))) 90 #define H(x, y, z) ((x) ^ (y) ^ (z)) 91 #define I(x, y, z) ((y) ^ ((x) | (~z))) 92 93 /* ROTATE_LEFT rotates x left n bits. */ 94 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n)))) 95 96 /* 97 * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4. 98 * Rotation is separate from addition to prevent recomputation. 99 */ 100 #define FF(a, b, c, d, x, s, ac) { \ 101 (a) += F ((b), (c), (d)) + (x) + (unsigned int)(ac); \ 102 (a) = ROTATE_LEFT ((a), (s)); \ 103 (a) += (b); \ 104 } 105 #define GG(a, b, c, d, x, s, ac) { \ 106 (a) += G ((b), (c), (d)) + (x) + (unsigned int)(ac); \ 107 (a) = ROTATE_LEFT ((a), (s)); \ 108 (a) += (b); \ 109 } 110 #define HH(a, b, c, d, x, s, ac) { \ 111 (a) += H ((b), (c), (d)) + (x) + (unsigned int)(ac); \ 112 (a) = ROTATE_LEFT ((a), (s)); \ 113 (a) += (b); \ 114 } 115 #define II(a, b, c, d, x, s, ac) { \ 116 (a) += I ((b), (c), (d)) + (x) + (unsigned int)(ac); \ 117 (a) = ROTATE_LEFT ((a), (s)); \ 118 (a) += (b); \ 119 } 120 121 /* MD5 initialization. Begins an MD5 operation, writing a new context. */ 122 123 void 124 MD5Init (context) 125 MD5_CTX *context; 126 { 127 128 context->count[0] = context->count[1] = 0; 129 130 /* Load magic initialization constants. */ 131 context->state[0] = 0x67452301; 132 context->state[1] = 0xefcdab89; 133 context->state[2] = 0x98badcfe; 134 context->state[3] = 0x10325476; 135 } 136 137 /* 138 * MD5 block update operation. Continues an MD5 message-digest 139 * operation, processing another message block, and updating the 140 * context. 141 */ 142 143 void 144 MD5Update (context, in, inputLen) 145 MD5_CTX *context; 146 const void *in; 147 unsigned int inputLen; 148 { 149 unsigned int i, idx, partLen; 150 const unsigned char *input = in; 151 152 /* Compute number of bytes mod 64 */ 153 idx = (unsigned int)((context->count[0] >> 3) & 0x3F); 154 155 /* Update number of bits */ 156 if ((context->count[0] += ((unsigned int)inputLen << 3)) 157 < ((unsigned int)inputLen << 3)) 158 context->count[1]++; 159 context->count[1] += ((unsigned int)inputLen >> 29); 160 161 partLen = 64 - idx; 162 163 /* Transform as many times as possible. */ 164 if (inputLen >= partLen) { 165 memcpy((void *)&context->buffer[idx], (const void *)input, 166 partLen); 167 MD5Transform (context->state, context->buffer); 168 169 for (i = partLen; i + 63 < inputLen; i += 64) 170 MD5Transform (context->state, &input[i]); 171 172 idx = 0; 173 } 174 else 175 i = 0; 176 177 /* Buffer remaining input */ 178 memcpy ((void *)&context->buffer[idx], (const void *)&input[i], 179 inputLen-i); 180 } 181 182 /* 183 * MD5 padding. Adds padding followed by original length. 184 */ 185 186 void 187 MD5Pad (context) 188 MD5_CTX *context; 189 { 190 unsigned char bits[8]; 191 unsigned int idx, padLen; 192 193 /* Save number of bits */ 194 Encode (bits, context->count, 8); 195 196 /* Pad out to 56 mod 64. */ 197 idx = (unsigned int)((context->count[0] >> 3) & 0x3f); 198 padLen = (idx < 56) ? (56 - idx) : (120 - idx); 199 MD5Update (context, PADDING, padLen); 200 201 /* Append length (before padding) */ 202 MD5Update (context, bits, 8); 203 } 204 205 /* 206 * MD5 finalization. Ends an MD5 message-digest operation, writing the 207 * the message digest and zeroizing the context. 208 */ 209 210 void 211 MD5Final (digest, context) 212 unsigned char digest[16]; 213 MD5_CTX *context; 214 { 215 /* Do padding. */ 216 MD5Pad (context); 217 218 /* Store state in digest */ 219 Encode (digest, context->state, 16); 220 221 /* Zeroize sensitive information. */ 222 memset ((void *)context, 0, sizeof (*context)); 223 } 224 225 /* MD5 basic transformation. Transforms state based on block. */ 226 227 static void 228 MD5Transform (state, block) 229 unsigned int state[4]; 230 const unsigned char block[64]; 231 { 232 unsigned int a = state[0], b = state[1], c = state[2], d = state[3], x[16]; 233 234 Decode (x, block, 64); 235 236 /* Round 1 */ 237 #define S11 7 238 #define S12 12 239 #define S13 17 240 #define S14 22 241 FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */ 242 FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */ 243 FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */ 244 FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */ 245 FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */ 246 FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */ 247 FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */ 248 FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */ 249 FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */ 250 FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */ 251 FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */ 252 FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */ 253 FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */ 254 FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */ 255 FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */ 256 FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */ 257 258 /* Round 2 */ 259 #define S21 5 260 #define S22 9 261 #define S23 14 262 #define S24 20 263 GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */ 264 GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */ 265 GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */ 266 GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */ 267 GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */ 268 GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */ 269 GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */ 270 GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */ 271 GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */ 272 GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */ 273 GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */ 274 GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */ 275 GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */ 276 GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */ 277 GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */ 278 GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */ 279 280 /* Round 3 */ 281 #define S31 4 282 #define S32 11 283 #define S33 16 284 #define S34 23 285 HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */ 286 HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */ 287 HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */ 288 HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */ 289 HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */ 290 HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */ 291 HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */ 292 HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */ 293 HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */ 294 HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */ 295 HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */ 296 HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */ 297 HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */ 298 HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */ 299 HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */ 300 HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */ 301 302 /* Round 4 */ 303 #define S41 6 304 #define S42 10 305 #define S43 15 306 #define S44 21 307 II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */ 308 II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */ 309 II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */ 310 II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */ 311 II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */ 312 II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */ 313 II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */ 314 II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */ 315 II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */ 316 II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */ 317 II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */ 318 II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */ 319 II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */ 320 II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */ 321 II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */ 322 II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */ 323 324 state[0] += a; 325 state[1] += b; 326 state[2] += c; 327 state[3] += d; 328 329 /* Zeroize sensitive information. */ 330 memset ((void *)x, 0, sizeof (x)); 331 } 332
