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 * Changed so as no longer to depend on Colin Plumb's `usual.h' header 18 * definitions 19 * - Ian Jackson <ian (at) chiark.greenend.org.uk>. 20 * Still in the public domain. 21 */ 22 23 #include <string.h> /* for memcpy() */ 24 25 #include "md5_utils.h" 26 27 void 28 byteSwap(UWORD32 *buf, unsigned words) { 29 md5byte *p; 30 31 /* Only swap bytes for big endian machines */ 32 int i = 1; 33 34 if (*(char *)&i == 1) 35 return; 36 37 p = (md5byte *)buf; 38 39 do { 40 *buf++ = (UWORD32)((unsigned)p[3] << 8 | p[2]) << 16 | 41 ((unsigned)p[1] << 8 | p[0]); 42 p += 4; 43 } while (--words); 44 } 45 46 /* 47 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious 48 * initialization constants. 49 */ 50 void 51 MD5Init(struct MD5Context *ctx) { 52 ctx->buf[0] = 0x67452301; 53 ctx->buf[1] = 0xefcdab89; 54 ctx->buf[2] = 0x98badcfe; 55 ctx->buf[3] = 0x10325476; 56 57 ctx->bytes[0] = 0; 58 ctx->bytes[1] = 0; 59 } 60 61 /* 62 * Update context to reflect the concatenation of another buffer full 63 * of bytes. 64 */ 65 void 66 MD5Update(struct MD5Context *ctx, md5byte const *buf, unsigned len) { 67 UWORD32 t; 68 69 /* Update byte count */ 70 71 t = ctx->bytes[0]; 72 73 if ((ctx->bytes[0] = t + len) < t) 74 ctx->bytes[1]++; /* Carry from low to high */ 75 76 t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */ 77 78 if (t > len) { 79 memcpy((md5byte *)ctx->in + 64 - t, buf, len); 80 return; 81 } 82 83 /* First chunk is an odd size */ 84 memcpy((md5byte *)ctx->in + 64 - t, buf, t); 85 byteSwap(ctx->in, 16); 86 MD5Transform(ctx->buf, ctx->in); 87 buf += t; 88 len -= t; 89 90 /* Process data in 64-byte chunks */ 91 while (len >= 64) { 92 memcpy(ctx->in, buf, 64); 93 byteSwap(ctx->in, 16); 94 MD5Transform(ctx->buf, ctx->in); 95 buf += 64; 96 len -= 64; 97 } 98 99 /* Handle any remaining bytes of data. */ 100 memcpy(ctx->in, buf, len); 101 } 102 103 /* 104 * Final wrapup - pad to 64-byte boundary with the bit pattern 105 * 1 0* (64-bit count of bits processed, MSB-first) 106 */ 107 void 108 MD5Final(md5byte digest[16], struct MD5Context *ctx) { 109 int count = ctx->bytes[0] & 0x3f; /* Number of bytes in ctx->in */ 110 md5byte *p = (md5byte *)ctx->in + count; 111 112 /* Set the first char of padding to 0x80. There is always room. */ 113 *p++ = 0x80; 114 115 /* Bytes of padding needed to make 56 bytes (-8..55) */ 116 count = 56 - 1 - count; 117 118 if (count < 0) { /* Padding forces an extra block */ 119 memset(p, 0, count + 8); 120 byteSwap(ctx->in, 16); 121 MD5Transform(ctx->buf, ctx->in); 122 p = (md5byte *)ctx->in; 123 count = 56; 124 } 125 126 memset(p, 0, count); 127 byteSwap(ctx->in, 14); 128 129 /* Append length in bits and transform */ 130 ctx->in[14] = ctx->bytes[0] << 3; 131 ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29; 132 MD5Transform(ctx->buf, ctx->in); 133 134 byteSwap(ctx->buf, 4); 135 memcpy(digest, ctx->buf, 16); 136 memset(ctx, 0, sizeof(*ctx)); /* In case it's sensitive */ 137 } 138 139 #ifndef ASM_MD5 140 141 /* The four core functions - F1 is optimized somewhat */ 142 143 /* #define F1(x, y, z) (x & y | ~x & z) */ 144 #define F1(x, y, z) (z ^ (x & (y ^ z))) 145 #define F2(x, y, z) F1(z, x, y) 146 #define F3(x, y, z) (x ^ y ^ z) 147 #define F4(x, y, z) (y ^ (x | ~z)) 148 149 /* This is the central step in the MD5 algorithm. */ 150 #define MD5STEP(f,w,x,y,z,in,s) \ 151 (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x) 152 153 /* 154 * The core of the MD5 algorithm, this alters an existing MD5 hash to 155 * reflect the addition of 16 longwords of new data. MD5Update blocks 156 * the data and converts bytes into longwords for this routine. 157 */ 158 void 159 MD5Transform(UWORD32 buf[4], UWORD32 const in[16]) { 160 register UWORD32 a, b, c, d; 161 162 a = buf[0]; 163 b = buf[1]; 164 c = buf[2]; 165 d = buf[3]; 166 167 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); 168 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); 169 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); 170 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); 171 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); 172 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); 173 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); 174 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); 175 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); 176 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); 177 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); 178 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); 179 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); 180 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); 181 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); 182 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); 183 184 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); 185 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); 186 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); 187 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); 188 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); 189 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); 190 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); 191 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); 192 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); 193 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); 194 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); 195 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); 196 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); 197 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); 198 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); 199 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); 200 201 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); 202 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); 203 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); 204 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); 205 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); 206 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); 207 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); 208 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); 209 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); 210 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); 211 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); 212 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); 213 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); 214 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); 215 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); 216 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); 217 218 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); 219 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); 220 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); 221 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); 222 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); 223 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); 224 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); 225 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); 226 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); 227 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); 228 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); 229 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); 230 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); 231 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); 232 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); 233 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); 234 235 buf[0] += a; 236 buf[1] += b; 237 buf[2] += c; 238 buf[3] += d; 239 } 240 241 #endif 242
