1 /* 2 * This code implements the MD5 message-digest algorithm. 3 * The algorithm is due to Ron Rivest. This code was 4 * written by Colin Plumb in 1993, no copyright is claimed. 5 * This code is in the public domain; do with it what you wish. 6 * 7 * Equivalent code is available from RSA Data Security, Inc. 8 * This code has been tested against that, and is equivalent, 9 * except that you don't need to include two pages of legalese 10 * with every copy. 11 * 12 * To compute the message digest of a chunk of bytes, declare an 13 * MD5Context structure, pass it to MD5Init, call MD5Update as 14 * needed on buffers full of bytes, and then call MD5Final, which 15 * will fill a supplied 16-byte array with the digest. 16 */ 17 #include <string.h> /* for memcpy() */ 18 #include "md5.h" 19 20 #ifndef HIGHFIRST 21 #define byteReverse(buf, len) /* Nothing */ 22 #else 23 void byteReverse(unsigned char *buf, unsigned longs); 24 25 #ifndef ASM_MD5 26 /* 27 * Note: this code is harmless on little-endian machines. 28 */ 29 void byteReverse(unsigned char *buf, unsigned longs) 30 { 31 uint32 t; 32 do { 33 t = (uint32)((unsigned)buf[3]<<8 | buf[2]) << 16 | 34 ((unsigned)buf[1]<<8 | buf[0]); 35 *(uint32 *)buf = t; 36 buf += 4; 37 } while (--longs); 38 } 39 #endif 40 #endif 41 42 /* 43 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious 44 * initialization constants. 45 */ 46 void 47 MD5Init(struct MD5Context *ctx) 48 { 49 ctx->buf[0] = 0x67452301; 50 ctx->buf[1] = 0xefcdab89; 51 ctx->buf[2] = 0x98badcfe; 52 ctx->buf[3] = 0x10325476; 53 54 ctx->bits[0] = 0; 55 ctx->bits[1] = 0; 56 } 57 58 /* 59 * Update context to reflect the concatenation of another buffer full 60 * of bytes. 61 */ 62 void 63 MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len) 64 { 65 uint32 t; 66 67 /* Update bitcount */ 68 69 t = ctx->bits[0]; 70 if ((ctx->bits[0] = t + ((uint32)len << 3)) < t) 71 ctx->bits[1]++; /* Carry from low to high */ 72 ctx->bits[1] += len >> 29; 73 74 t = (t >> 3) & 0x3f; /* Bytes already in shsInfo->data */ 75 76 /* Handle any leading odd-sized chunks */ 77 78 if ( t ) { 79 unsigned char *p = (unsigned char *)ctx->in + t; 80 81 t = 64-t; 82 if (len < t) { 83 memcpy(p, buf, len); 84 return; 85 } 86 memcpy(p, buf, t); 87 byteReverse(ctx->in, 16); 88 MD5Transform(ctx->buf, (uint32 *)ctx->in); 89 buf += t; 90 len -= t; 91 } 92 93 /* Process data in 64-byte chunks */ 94 95 while (len >= 64) { 96 memcpy(ctx->in, buf, 64); 97 byteReverse(ctx->in, 16); 98 MD5Transform(ctx->buf, (uint32 *)ctx->in); 99 buf += 64; 100 len -= 64; 101 } 102 103 /* Handle any remaining bytes of data. */ 104 105 memcpy(ctx->in, buf, len); 106 } 107 108 /* 109 * Final wrapup - pad to 64-byte boundary with the bit pattern 110 * 1 0* (64-bit count of bits processed, MSB-first) 111 */ 112 void 113 MD5Final(unsigned char digest[16], struct MD5Context *ctx) 114 { 115 unsigned count; 116 unsigned char *p; 117 118 /* Compute number of bytes mod 64 */ 119 count = (ctx->bits[0] >> 3) & 0x3F; 120 121 /* Set the first char of padding to 0x80. This is safe since there is 122 always at least one byte free */ 123 p = (unsigned char*)(ctx->in) + count; 124 *p++ = 0x80; 125 126 /* Bytes of padding needed to make 64 bytes */ 127 count = 64 - 1 - count; 128 129 /* Pad out to 56 mod 64 */ 130 if (count < 8) { 131 /* Two lots of padding: Pad the first block to 64 bytes */ 132 memset(p, 0, count); 133 byteReverse(ctx->in, 16); 134 MD5Transform(ctx->buf, (uint32 *)ctx->in); 135 136 /* Now fill the next block with 56 bytes */ 137 memset(ctx->in, 0, 56); 138 } else { 139 /* Pad block to 56 bytes */ 140 memset(p, 0, count-8); 141 } 142 byteReverse(ctx->in, 14); 143 144 /* Append length in bits and transform */ 145 ((uint32 *)ctx->in)[ 14 ] = ctx->bits[0]; 146 ((uint32 *)ctx->in)[ 15 ] = ctx->bits[1]; 147 148 MD5Transform(ctx->buf, (uint32 *)ctx->in); 149 byteReverse((unsigned char *)ctx->buf, 4); 150 memcpy(digest, ctx->buf, 16); 151 memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */ 152 } 153 154 #ifndef ASM_MD5 155 156 /* The four core functions - F1 is optimized somewhat */ 157 158 /* #define F1(x, y, z) (x & y | ~x & z) */ 159 #define F1(x, y, z) (z ^ (x & (y ^ z))) 160 #define F2(x, y, z) F1(z, x, y) 161 #define F3(x, y, z) (x ^ y ^ z) 162 #define F4(x, y, z) (y ^ (x | ~z)) 163 164 /* This is the central step in the MD5 algorithm. */ 165 #define MD5STEP(f, w, x, y, z, data, s) \ 166 ( w += f(x, y, z) + data, w = w<<s | w>>(32-s), w += x ) 167 168 /* 169 * The core of the MD5 algorithm, this alters an existing MD5 hash to 170 * reflect the addition of 16 longwords of new data. MD5Update blocks 171 * the data and converts bytes into longwords for this routine. 172 */ 173 void 174 MD5Transform(uint32 buf[4], uint32 const in[16]) 175 { 176 register uint32 a, b, c, d; 177 178 a = buf[0]; 179 b = buf[1]; 180 c = buf[2]; 181 d = buf[3]; 182 183 MD5STEP(F1, a, b, c, d, in[ 0]+0xd76aa478, 7); 184 MD5STEP(F1, d, a, b, c, in[ 1]+0xe8c7b756, 12); 185 MD5STEP(F1, c, d, a, b, in[ 2]+0x242070db, 17); 186 MD5STEP(F1, b, c, d, a, in[ 3]+0xc1bdceee, 22); 187 MD5STEP(F1, a, b, c, d, in[ 4]+0xf57c0faf, 7); 188 MD5STEP(F1, d, a, b, c, in[ 5]+0x4787c62a, 12); 189 MD5STEP(F1, c, d, a, b, in[ 6]+0xa8304613, 17); 190 MD5STEP(F1, b, c, d, a, in[ 7]+0xfd469501, 22); 191 MD5STEP(F1, a, b, c, d, in[ 8]+0x698098d8, 7); 192 MD5STEP(F1, d, a, b, c, in[ 9]+0x8b44f7af, 12); 193 MD5STEP(F1, c, d, a, b, in[10]+0xffff5bb1, 17); 194 MD5STEP(F1, b, c, d, a, in[11]+0x895cd7be, 22); 195 MD5STEP(F1, a, b, c, d, in[12]+0x6b901122, 7); 196 MD5STEP(F1, d, a, b, c, in[13]+0xfd987193, 12); 197 MD5STEP(F1, c, d, a, b, in[14]+0xa679438e, 17); 198 MD5STEP(F1, b, c, d, a, in[15]+0x49b40821, 22); 199 200 MD5STEP(F2, a, b, c, d, in[ 1]+0xf61e2562, 5); 201 MD5STEP(F2, d, a, b, c, in[ 6]+0xc040b340, 9); 202 MD5STEP(F2, c, d, a, b, in[11]+0x265e5a51, 14); 203 MD5STEP(F2, b, c, d, a, in[ 0]+0xe9b6c7aa, 20); 204 MD5STEP(F2, a, b, c, d, in[ 5]+0xd62f105d, 5); 205 MD5STEP(F2, d, a, b, c, in[10]+0x02441453, 9); 206 MD5STEP(F2, c, d, a, b, in[15]+0xd8a1e681, 14); 207 MD5STEP(F2, b, c, d, a, in[ 4]+0xe7d3fbc8, 20); 208 MD5STEP(F2, a, b, c, d, in[ 9]+0x21e1cde6, 5); 209 MD5STEP(F2, d, a, b, c, in[14]+0xc33707d6, 9); 210 MD5STEP(F2, c, d, a, b, in[ 3]+0xf4d50d87, 14); 211 MD5STEP(F2, b, c, d, a, in[ 8]+0x455a14ed, 20); 212 MD5STEP(F2, a, b, c, d, in[13]+0xa9e3e905, 5); 213 MD5STEP(F2, d, a, b, c, in[ 2]+0xfcefa3f8, 9); 214 MD5STEP(F2, c, d, a, b, in[ 7]+0x676f02d9, 14); 215 MD5STEP(F2, b, c, d, a, in[12]+0x8d2a4c8a, 20); 216 217 MD5STEP(F3, a, b, c, d, in[ 5]+0xfffa3942, 4); 218 MD5STEP(F3, d, a, b, c, in[ 8]+0x8771f681, 11); 219 MD5STEP(F3, c, d, a, b, in[11]+0x6d9d6122, 16); 220 MD5STEP(F3, b, c, d, a, in[14]+0xfde5380c, 23); 221 MD5STEP(F3, a, b, c, d, in[ 1]+0xa4beea44, 4); 222 MD5STEP(F3, d, a, b, c, in[ 4]+0x4bdecfa9, 11); 223 MD5STEP(F3, c, d, a, b, in[ 7]+0xf6bb4b60, 16); 224 MD5STEP(F3, b, c, d, a, in[10]+0xbebfbc70, 23); 225 MD5STEP(F3, a, b, c, d, in[13]+0x289b7ec6, 4); 226 MD5STEP(F3, d, a, b, c, in[ 0]+0xeaa127fa, 11); 227 MD5STEP(F3, c, d, a, b, in[ 3]+0xd4ef3085, 16); 228 MD5STEP(F3, b, c, d, a, in[ 6]+0x04881d05, 23); 229 MD5STEP(F3, a, b, c, d, in[ 9]+0xd9d4d039, 4); 230 MD5STEP(F3, d, a, b, c, in[12]+0xe6db99e5, 11); 231 MD5STEP(F3, c, d, a, b, in[15]+0x1fa27cf8, 16); 232 MD5STEP(F3, b, c, d, a, in[ 2]+0xc4ac5665, 23); 233 234 MD5STEP(F4, a, b, c, d, in[ 0]+0xf4292244, 6); 235 MD5STEP(F4, d, a, b, c, in[ 7]+0x432aff97, 10); 236 MD5STEP(F4, c, d, a, b, in[14]+0xab9423a7, 15); 237 MD5STEP(F4, b, c, d, a, in[ 5]+0xfc93a039, 21); 238 MD5STEP(F4, a, b, c, d, in[12]+0x655b59c3, 6); 239 MD5STEP(F4, d, a, b, c, in[ 3]+0x8f0ccc92, 10); 240 MD5STEP(F4, c, d, a, b, in[10]+0xffeff47d, 15); 241 MD5STEP(F4, b, c, d, a, in[ 1]+0x85845dd1, 21); 242 MD5STEP(F4, a, b, c, d, in[ 8]+0x6fa87e4f, 6); 243 MD5STEP(F4, d, a, b, c, in[15]+0xfe2ce6e0, 10); 244 MD5STEP(F4, c, d, a, b, in[ 6]+0xa3014314, 15); 245 MD5STEP(F4, b, c, d, a, in[13]+0x4e0811a1, 21); 246 MD5STEP(F4, a, b, c, d, in[ 4]+0xf7537e82, 6); 247 MD5STEP(F4, d, a, b, c, in[11]+0xbd3af235, 10); 248 MD5STEP(F4, c, d, a, b, in[ 2]+0x2ad7d2bb, 15); 249 MD5STEP(F4, b, c, d, a, in[ 9]+0xeb86d391, 21); 250 251 buf[0] += a; 252 buf[1] += b; 253 buf[2] += c; 254 buf[3] += d; 255 } 256 #endif 257
