md5.c (9550B)
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; now uses stuff from dpkg's config.h. 19 * - Ian Jackson <ijackson@nyx.cs.du.edu>. 20 * Still in the public domain. 21 * 22 * Josh Coalson: made some changes to integrate with libFLAC. 23 * Still in the public domain. 24 */ 25 26 #include <stdlib.h> /* for malloc() */ 27 #include <string.h> /* for memcpy() */ 28 29 #include "private/md5.h" 30 31 #ifdef HAVE_CONFIG_H 32 #include <config.h> 33 #endif 34 35 #ifndef FLaC__INLINE 36 #define FLaC__INLINE 37 #endif 38 39 static FLAC__bool is_big_endian_host_; 40 41 #ifndef ASM_MD5 42 43 /* The four core functions - F1 is optimized somewhat */ 44 45 /* #define F1(x, y, z) (x & y | ~x & z) */ 46 #define F1(x, y, z) (z ^ (x & (y ^ z))) 47 #define F2(x, y, z) F1(z, x, y) 48 #define F3(x, y, z) (x ^ y ^ z) 49 #define F4(x, y, z) (y ^ (x | ~z)) 50 51 /* This is the central step in the MD5 algorithm. */ 52 #define MD5STEP(f,w,x,y,z,in,s) \ 53 (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x) 54 55 /* 56 * The core of the MD5 algorithm, this alters an existing MD5 hash to 57 * reflect the addition of 16 longwords of new data. MD5Update blocks 58 * the data and converts bytes into longwords for this routine. 59 */ 60 FLaC__INLINE 61 void 62 FLAC__MD5Transform(FLAC__uint32 buf[4], FLAC__uint32 const in[16]) 63 { 64 register FLAC__uint32 a, b, c, d; 65 66 a = buf[0]; 67 b = buf[1]; 68 c = buf[2]; 69 d = buf[3]; 70 71 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); 72 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); 73 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); 74 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); 75 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); 76 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); 77 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); 78 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); 79 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); 80 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); 81 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); 82 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); 83 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); 84 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); 85 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); 86 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); 87 88 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); 89 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); 90 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); 91 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); 92 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); 93 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); 94 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); 95 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); 96 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); 97 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); 98 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); 99 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); 100 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); 101 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); 102 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); 103 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); 104 105 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); 106 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); 107 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); 108 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); 109 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); 110 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); 111 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); 112 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); 113 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); 114 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); 115 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); 116 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); 117 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); 118 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); 119 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); 120 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); 121 122 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); 123 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); 124 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); 125 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); 126 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); 127 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); 128 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); 129 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); 130 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); 131 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); 132 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); 133 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); 134 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); 135 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); 136 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); 137 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); 138 139 buf[0] += a; 140 buf[1] += b; 141 buf[2] += c; 142 buf[3] += d; 143 } 144 145 #endif 146 147 FLaC__INLINE 148 void 149 byteSwap(FLAC__uint32 *buf, unsigned words) 150 { 151 md5byte *p = (md5byte *)buf; 152 153 if(!is_big_endian_host_) 154 return; 155 do { 156 *buf++ = (FLAC__uint32)((unsigned)p[3] << 8 | p[2]) << 16 | ((unsigned)p[1] << 8 | p[0]); 157 p += 4; 158 } while (--words); 159 } 160 161 /* 162 * Start MD5 accumulation. Set bit count to 0 and buffer to mysterious 163 * initialization constants. 164 */ 165 void 166 FLAC__MD5Init(struct FLAC__MD5Context *ctx) 167 { 168 FLAC__uint32 test = 1; 169 170 is_big_endian_host_ = (*((FLAC__byte*)(&test)))? false : true; 171 172 ctx->buf[0] = 0x67452301; 173 ctx->buf[1] = 0xefcdab89; 174 ctx->buf[2] = 0x98badcfe; 175 ctx->buf[3] = 0x10325476; 176 177 ctx->bytes[0] = 0; 178 ctx->bytes[1] = 0; 179 180 ctx->internal_buf = 0; 181 ctx->capacity = 0; 182 } 183 184 /* 185 * Update context to reflect the concatenation of another buffer full 186 * of bytes. 187 */ 188 void 189 FLAC__MD5Update(struct FLAC__MD5Context *ctx, md5byte const *buf, unsigned len) 190 { 191 FLAC__uint32 t; 192 193 /* Update byte count */ 194 195 t = ctx->bytes[0]; 196 if ((ctx->bytes[0] = t + len) < t) 197 ctx->bytes[1]++; /* Carry from low to high */ 198 199 t = 64 - (t & 0x3f); /* Space available in ctx->in (at least 1) */ 200 if (t > len) { 201 memcpy((md5byte *)ctx->in + 64 - t, buf, len); 202 return; 203 } 204 /* First chunk is an odd size */ 205 memcpy((md5byte *)ctx->in + 64 - t, buf, t); 206 byteSwap(ctx->in, 16); 207 FLAC__MD5Transform(ctx->buf, ctx->in); 208 buf += t; 209 len -= t; 210 211 /* Process data in 64-byte chunks */ 212 while (len >= 64) { 213 memcpy(ctx->in, buf, 64); 214 byteSwap(ctx->in, 16); 215 FLAC__MD5Transform(ctx->buf, ctx->in); 216 buf += 64; 217 len -= 64; 218 } 219 220 /* Handle any remaining bytes of data. */ 221 memcpy(ctx->in, buf, len); 222 } 223 224 /* 225 * Convert the incoming audio signal to a byte stream and FLAC__MD5Update it. 226 */ 227 FLAC__bool 228 FLAC__MD5Accumulate(struct FLAC__MD5Context *ctx, const FLAC__int32 * const signal[], unsigned channels, unsigned samples, unsigned bytes_per_sample) 229 { 230 unsigned channel, sample, a_byte; 231 FLAC__int32 a_word; 232 FLAC__byte *buf_; 233 const unsigned bytes_needed = channels * samples * bytes_per_sample; 234 235 if(ctx->capacity < bytes_needed) { 236 FLAC__byte *tmp = (FLAC__byte*)realloc(ctx->internal_buf, bytes_needed); 237 if(0 == tmp) { 238 free(ctx->internal_buf); 239 if(0 == (ctx->internal_buf = (FLAC__byte*)malloc(bytes_needed))) 240 return false; 241 } 242 ctx->internal_buf = tmp; 243 ctx->capacity = bytes_needed; 244 } 245 246 buf_ = ctx->internal_buf; 247 248 #ifdef FLAC__CPU_IA32 249 if(channels == 2 && bytes_per_sample == 2) { 250 memcpy(buf_, signal[0], sizeof(FLAC__int32) * samples); 251 buf_ += sizeof(FLAC__int16); 252 for(sample = 0; sample < samples; sample++) 253 ((FLAC__int16 *)buf_)[2 * sample] = (FLAC__int16)signal[1][sample]; 254 } 255 else if(channels == 1 && bytes_per_sample == 2) { 256 for(sample = 0; sample < samples; sample++) 257 ((FLAC__int16 *)buf_)[sample] = (FLAC__int16)signal[0][sample]; 258 } 259 else 260 #endif 261 for(sample = 0; sample < samples; sample++) { 262 for(channel = 0; channel < channels; channel++) { 263 a_word = signal[channel][sample]; 264 for(a_byte = 0; a_byte < bytes_per_sample; a_byte++) { 265 *buf_++ = (FLAC__byte)(a_word & 0xff); 266 a_word >>= 8; 267 } 268 } 269 } 270 271 FLAC__MD5Update(ctx, ctx->internal_buf, bytes_needed); 272 273 return true; 274 } 275 276 /* 277 * Final wrapup - pad to 64-byte boundary with the bit pattern 278 * 1 0* (64-bit count of bits processed, MSB-first) 279 */ 280 void 281 FLAC__MD5Final(md5byte digest[16], struct FLAC__MD5Context *ctx) 282 { 283 int count = ctx->bytes[0] & 0x3f; /* Number of bytes in ctx->in */ 284 md5byte *p = (md5byte *)ctx->in + count; 285 286 /* Set the first char of padding to 0x80. There is always room. */ 287 *p++ = 0x80; 288 289 /* Bytes of padding needed to make 56 bytes (-8..55) */ 290 count = 56 - 1 - count; 291 292 if (count < 0) { /* Padding forces an extra block */ 293 memset(p, 0, count + 8); 294 byteSwap(ctx->in, 16); 295 FLAC__MD5Transform(ctx->buf, ctx->in); 296 p = (md5byte *)ctx->in; 297 count = 56; 298 } 299 memset(p, 0, count); 300 byteSwap(ctx->in, 14); 301 302 /* Append length in bits and transform */ 303 ctx->in[14] = ctx->bytes[0] << 3; 304 ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29; 305 FLAC__MD5Transform(ctx->buf, ctx->in); 306 307 byteSwap(ctx->buf, 4); 308 memcpy(digest, ctx->buf, 16); 309 memset(ctx, 0, sizeof(ctx)); /* In case it's sensitive */ 310 if(0 != ctx->internal_buf) { 311 free(ctx->internal_buf); 312 ctx->internal_buf = 0; 313 ctx->capacity = 0; 314 } 315 }