Guido van Rossum | 13ecc7a | 1993-11-01 16:19:05 +0000 | [diff] [blame] | 1 | /* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm |
| 2 | */ |
| 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 | |
Guido van Rossum | b6775db | 1994-08-01 11:34:53 +0000 | [diff] [blame^] | 26 | #ifdef HAVE_CONFIG_H |
| 27 | #include "config.h" |
| 28 | #endif |
Guido van Rossum | 13ecc7a | 1993-11-01 16:19:05 +0000 | [diff] [blame] | 29 | #include "md5.h" |
| 30 | |
| 31 | /* Constants for MD5Transform routine. |
| 32 | */ |
| 33 | |
| 34 | #define S11 7 |
| 35 | #define S12 12 |
| 36 | #define S13 17 |
| 37 | #define S14 22 |
| 38 | #define S21 5 |
| 39 | #define S22 9 |
| 40 | #define S23 14 |
| 41 | #define S24 20 |
| 42 | #define S31 4 |
| 43 | #define S32 11 |
| 44 | #define S33 16 |
| 45 | #define S34 23 |
| 46 | #define S41 6 |
| 47 | #define S42 10 |
| 48 | #define S43 15 |
| 49 | #define S44 21 |
| 50 | |
| 51 | static void MD5Transform PROTO_LIST ((UINT4 [4], unsigned char [64])); |
| 52 | static void Encode PROTO_LIST |
| 53 | ((unsigned char *, UINT4 *, unsigned int)); |
| 54 | static void Decode PROTO_LIST |
| 55 | ((UINT4 *, unsigned char *, unsigned int)); |
| 56 | static void MD5_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int)); |
| 57 | static void MD5_memset PROTO_LIST ((POINTER, int, unsigned int)); |
| 58 | |
| 59 | static unsigned char PADDING[64] = { |
| 60 | 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 61 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, |
| 62 | 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 |
| 63 | }; |
| 64 | |
| 65 | /* F, G, H and I are basic MD5 functions. |
| 66 | */ |
| 67 | #define F(x, y, z) (((x) & (y)) | ((~x) & (z))) |
| 68 | #define G(x, y, z) (((x) & (z)) | ((y) & (~z))) |
| 69 | #define H(x, y, z) ((x) ^ (y) ^ (z)) |
| 70 | #define I(x, y, z) ((y) ^ ((x) | (~z))) |
| 71 | |
| 72 | /* ROTATE_LEFT rotates x left n bits. |
| 73 | */ |
| 74 | #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n)))) |
| 75 | |
| 76 | /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4. |
| 77 | Rotation is separate from addition to prevent recomputation. |
| 78 | */ |
| 79 | #define FF(a, b, c, d, x, s, ac) { \ |
| 80 | (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \ |
| 81 | (a) = ROTATE_LEFT ((a), (s)); \ |
| 82 | (a) += (b); \ |
| 83 | } |
| 84 | #define GG(a, b, c, d, x, s, ac) { \ |
| 85 | (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \ |
| 86 | (a) = ROTATE_LEFT ((a), (s)); \ |
| 87 | (a) += (b); \ |
| 88 | } |
| 89 | #define HH(a, b, c, d, x, s, ac) { \ |
| 90 | (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \ |
| 91 | (a) = ROTATE_LEFT ((a), (s)); \ |
| 92 | (a) += (b); \ |
| 93 | } |
| 94 | #define II(a, b, c, d, x, s, ac) { \ |
| 95 | (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \ |
| 96 | (a) = ROTATE_LEFT ((a), (s)); \ |
| 97 | (a) += (b); \ |
| 98 | } |
| 99 | |
| 100 | /* MD5 initialization. Begins an MD5 operation, writing a new context. |
| 101 | */ |
| 102 | void MD5Init (context) |
| 103 | MD5_CTX *context; /* context */ |
| 104 | { |
| 105 | context->count[0] = context->count[1] = 0; |
| 106 | /* Load magic initialization constants. |
| 107 | */ |
| 108 | context->state[0] = 0x67452301; |
| 109 | context->state[1] = 0xefcdab89; |
| 110 | context->state[2] = 0x98badcfe; |
| 111 | context->state[3] = 0x10325476; |
| 112 | } |
| 113 | |
| 114 | /* MD5 block update operation. Continues an MD5 message-digest |
| 115 | operation, processing another message block, and updating the |
| 116 | context. |
| 117 | */ |
| 118 | void MD5Update (context, input, inputLen) |
| 119 | MD5_CTX *context; /* context */ |
| 120 | unsigned char *input; /* input block */ |
| 121 | unsigned int inputLen; /* length of input block */ |
| 122 | { |
| 123 | unsigned int i, index, partLen; |
| 124 | |
| 125 | /* Compute number of bytes mod 64 */ |
| 126 | index = (unsigned int)((context->count[0] >> 3) & 0x3F); |
| 127 | |
| 128 | /* Update number of bits */ |
| 129 | if ((context->count[0] += ((UINT4)inputLen << 3)) |
| 130 | < ((UINT4)inputLen << 3)) |
| 131 | context->count[1]++; |
| 132 | context->count[1] += ((UINT4)inputLen >> 29); |
| 133 | |
| 134 | partLen = 64 - index; |
| 135 | |
| 136 | /* Transform as many times as possible. |
| 137 | */ |
| 138 | if (inputLen >= partLen) { |
| 139 | MD5_memcpy |
| 140 | ((POINTER)&context->buffer[index], (POINTER)input, partLen); |
| 141 | MD5Transform (context->state, context->buffer); |
| 142 | |
| 143 | for (i = partLen; i + 63 < inputLen; i += 64) |
| 144 | MD5Transform (context->state, &input[i]); |
| 145 | |
| 146 | index = 0; |
| 147 | } |
| 148 | else |
| 149 | i = 0; |
| 150 | |
| 151 | /* Buffer remaining input */ |
| 152 | MD5_memcpy |
| 153 | ((POINTER)&context->buffer[index], (POINTER)&input[i], |
| 154 | inputLen-i); |
| 155 | } |
| 156 | |
| 157 | /* MD5 finalization. Ends an MD5 message-digest operation, writing the |
| 158 | the message digest and zeroizing the context. |
| 159 | */ |
| 160 | void MD5Final (digest, context) |
| 161 | unsigned char digest[16]; /* message digest */ |
| 162 | MD5_CTX *context; /* context */ |
| 163 | { |
| 164 | unsigned char bits[8]; |
| 165 | unsigned int index, padLen; |
| 166 | |
| 167 | /* Save number of bits */ |
| 168 | Encode (bits, context->count, 8); |
| 169 | |
| 170 | /* Pad out to 56 mod 64. |
| 171 | */ |
| 172 | index = (unsigned int)((context->count[0] >> 3) & 0x3f); |
| 173 | padLen = (index < 56) ? (56 - index) : (120 - index); |
| 174 | MD5Update (context, PADDING, padLen); |
| 175 | |
| 176 | /* Append length (before padding) */ |
| 177 | MD5Update (context, bits, 8); |
| 178 | |
| 179 | /* Store state in digest */ |
| 180 | Encode (digest, context->state, 16); |
| 181 | |
| 182 | /* Zeroize sensitive information. |
| 183 | */ |
| 184 | MD5_memset ((POINTER)context, 0, sizeof (*context)); |
| 185 | } |
| 186 | |
| 187 | /* MD5 basic transformation. Transforms state based on block. |
| 188 | */ |
| 189 | static void MD5Transform (state, block) |
| 190 | UINT4 state[4]; |
| 191 | unsigned char block[64]; |
| 192 | { |
| 193 | UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16]; |
| 194 | |
| 195 | Decode (x, block, 64); |
| 196 | |
| 197 | /* Round 1 */ |
| 198 | FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */ |
| 199 | FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */ |
| 200 | FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */ |
| 201 | FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */ |
| 202 | FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */ |
| 203 | FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */ |
| 204 | FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */ |
| 205 | FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */ |
| 206 | FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */ |
| 207 | FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */ |
| 208 | FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */ |
| 209 | FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */ |
| 210 | FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */ |
| 211 | FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */ |
| 212 | FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */ |
| 213 | FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */ |
| 214 | |
| 215 | /* Round 2 */ |
| 216 | GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */ |
| 217 | GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */ |
| 218 | GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */ |
| 219 | GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */ |
| 220 | GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */ |
| 221 | GG (d, a, b, c, x[10], S22, 0x2441453); /* 22 */ |
| 222 | GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */ |
| 223 | GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */ |
| 224 | GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */ |
| 225 | GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */ |
| 226 | GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */ |
| 227 | GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */ |
| 228 | GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */ |
| 229 | GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */ |
| 230 | GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */ |
| 231 | GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */ |
| 232 | |
| 233 | /* Round 3 */ |
| 234 | HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */ |
| 235 | HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */ |
| 236 | HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */ |
| 237 | HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */ |
| 238 | HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */ |
| 239 | HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */ |
| 240 | HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */ |
| 241 | HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */ |
| 242 | HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */ |
| 243 | HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */ |
| 244 | HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */ |
| 245 | HH (b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */ |
| 246 | HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */ |
| 247 | HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */ |
| 248 | HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */ |
| 249 | HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */ |
| 250 | |
| 251 | /* Round 4 */ |
| 252 | II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */ |
| 253 | II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */ |
| 254 | II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */ |
| 255 | II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */ |
| 256 | II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */ |
| 257 | II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */ |
| 258 | II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */ |
| 259 | II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */ |
| 260 | II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */ |
| 261 | II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */ |
| 262 | II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */ |
| 263 | II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */ |
| 264 | II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */ |
| 265 | II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */ |
| 266 | II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */ |
| 267 | II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */ |
| 268 | |
| 269 | state[0] += a; |
| 270 | state[1] += b; |
| 271 | state[2] += c; |
| 272 | state[3] += d; |
| 273 | |
| 274 | /* Zeroize sensitive information. |
| 275 | */ |
| 276 | MD5_memset ((POINTER)x, 0, sizeof (x)); |
| 277 | } |
| 278 | |
| 279 | /* Encodes input (UINT4) into output (unsigned char). Assumes len is |
| 280 | a multiple of 4. |
| 281 | */ |
| 282 | static void Encode (output, input, len) |
| 283 | unsigned char *output; |
| 284 | UINT4 *input; |
| 285 | unsigned int len; |
| 286 | { |
| 287 | unsigned int i, j; |
| 288 | |
| 289 | for (i = 0, j = 0; j < len; i++, j += 4) { |
| 290 | output[j] = (unsigned char)(input[i] & 0xff); |
| 291 | output[j+1] = (unsigned char)((input[i] >> 8) & 0xff); |
| 292 | output[j+2] = (unsigned char)((input[i] >> 16) & 0xff); |
| 293 | output[j+3] = (unsigned char)((input[i] >> 24) & 0xff); |
| 294 | } |
| 295 | } |
| 296 | |
| 297 | /* Decodes input (unsigned char) into output (UINT4). Assumes len is |
| 298 | a multiple of 4. |
| 299 | */ |
| 300 | static void Decode (output, input, len) |
| 301 | UINT4 *output; |
| 302 | unsigned char *input; |
| 303 | unsigned int len; |
| 304 | { |
| 305 | unsigned int i, j; |
| 306 | |
| 307 | for (i = 0, j = 0; j < len; i++, j += 4) |
| 308 | output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) | |
| 309 | (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24); |
| 310 | } |
| 311 | |
| 312 | /* Note: Replace "for loop" with standard memcpy if possible. |
| 313 | */ |
| 314 | |
| 315 | static void MD5_memcpy (output, input, len) |
| 316 | POINTER output; |
| 317 | POINTER input; |
| 318 | unsigned int len; |
| 319 | { |
| 320 | unsigned int i; |
| 321 | |
| 322 | for (i = 0; i < len; i++) |
| 323 | output[i] = input[i]; |
| 324 | } |
| 325 | |
| 326 | /* Note: Replace "for loop" with standard memset if possible. |
| 327 | */ |
| 328 | static void MD5_memset (output, value, len) |
| 329 | POINTER output; |
| 330 | int value; |
| 331 | unsigned int len; |
| 332 | { |
| 333 | unsigned int i; |
| 334 | |
| 335 | for (i = 0; i < len; i++) |
| 336 | ((char *)output)[i] = (char)value; |
| 337 | } |