main/md5.c

   1
   2 /*!\file
   3 \brief     MD5 checksum routines used for authentication.  Not covered by GPL, but
   4    in the public domain as per the copyright below */
   5
   6 /*
   7  * This code implements the MD5 message-digest algorithm.
   8  * The algorithm is due to Ron Rivest.  This code was
   9  * written by Colin Plumb in 1993, no copyright is claimed.
  10  * This code is in the public domain; do with it what you wish.
  11  *
  12  * Equivalent code is available from RSA Data Security, Inc.
  13  * This code has been tested against that, and is equivalent,
  14  * except that you don't need to include two pages of legalese
  15  * with every copy.
  16  *
  17  * To compute the message digest of a chunk of bytes, declare an
  18  * MD5Context structure, pass it to MD5Init, call MD5Update as
  19  * needed on buffers full of bytes, and then call MD5Final, which
  20  * will fill a supplied 16-byte array with the digest.
  21  */
  22
  23 #include "asterisk.h"
  24
  25 ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
  26
  27 #include <string.h>             /* for memcpy() */
  28
  29 #include "asterisk/endian.h"
  30 #include "asterisk/md5.h"
  31
  32 # if __BYTE_ORDER == __BIG_ENDIAN
  33 #  define HIGHFIRST 1
  34 # endif
  35 #ifndef HIGHFIRST
  36 #define byteReverse(buf, len)   /* Nothing */
  37 #else
  38 void byteReverse(unsigned char *buf, unsigned longs);
  39
  40 #ifndef ASM_MD5
  41 /*
  42  * Note: this code is harmless on little-endian machines.
  43  */
  44 void byteReverse(unsigned char *buf, unsigned longs)
  45 {
  46         uint32_t t;
  47         do {
  48                 t = (uint32_t) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
  49                         ((unsigned) buf[1] << 8 | buf[0]);
  50                 *(uint32_t *) buf = t;
  51                 buf += 4;
  52         } while (--longs);
  53 }
  54 #endif
  55 #endif
  56
  57 /*
  58  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
  59  * initialization constants.
  60  */
  61 void MD5Init(struct MD5Context *ctx)
  62 {
  63         ctx->buf[0] = 0x67452301;
  64         ctx->buf[1] = 0xefcdab89;
  65         ctx->buf[2] = 0x98badcfe;
  66         ctx->buf[3] = 0x10325476;
  67
  68         ctx->bits[0] = 0;
  69         ctx->bits[1] = 0;
  70 }
  71
  72 /*
  73  * Update context to reflect the concatenation of another buffer full
  74  * of bytes.
  75  */
  76 void MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len)
  77 {
  78         uint32_t t;
  79
  80         /* Update bitcount */
  81
  82         t = ctx->bits[0];
  83         if ((ctx->bits[0] = t + ((uint32_t) len << 3)) < t)
  84                 ctx->bits[1]++;         /* Carry from low to high */
  85         ctx->bits[1] += len >> 29;
  86
  87         t = (t >> 3) & 0x3f;    /* Bytes already in shsInfo->data */
  88
  89         /* Handle any leading odd-sized chunks */
  90
  91         if (t) {
  92                 unsigned char *p = (unsigned char *) ctx->in + t;
  93
  94                 t = 64 - t;
  95                 if (len < t) {
  96                         memcpy(p, buf, len);
  97                         return;
  98                 }
  99                 memcpy(p, buf, t);
 100                 byteReverse(ctx->in, 16);
 101                 MD5Transform(ctx->buf, (uint32_t *) ctx->in);
 102                 buf += t;
 103                 len -= t;
 104         }
 105         /* Process data in 64-byte chunks */
 106
 107         while (len >= 64) {
 108                 memcpy(ctx->in, buf, 64);
 109                 byteReverse(ctx->in, 16);
 110                 MD5Transform(ctx->buf, (uint32_t *) ctx->in);
 111                 buf += 64;
 112                 len -= 64;
 113         }
 114
 115         /* Handle any remaining bytes of data. */
 116
 117         memcpy(ctx->in, buf, len);
 118 }
 119
 120 /*
 121  * Final wrapup - pad to 64-byte boundary with the bit pattern
 122  * 1 0* (64-bit count of bits processed, MSB-first)
 123  */
 124 void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
 125 {
 126         unsigned count;
 127         unsigned char *p;
 128
 129         /* Compute number of bytes mod 64 */
 130         count = (ctx->bits[0] >> 3) & 0x3F;
 131
 132         /* Set the first char of padding to 0x80.  This is safe since there is
 133            always at least one byte free */
 134         p = ctx->in + count;
 135         *p++ = 0x80;
 136
 137         /* Bytes of padding needed to make 64 bytes */
 138         count = 64 - 1 - count;
 139
 140         /* Pad out to 56 mod 64 */
 141         if (count < 8) {
 142                 /* Two lots of padding:  Pad the first block to 64 bytes */
 143                 memset(p, 0, count);
 144                 byteReverse(ctx->in, 16);
 145                 MD5Transform(ctx->buf, (uint32_t *) ctx->in);
 146
 147                 /* Now fill the next block with 56 bytes */
 148                 memset(ctx->in, 0, 56);
 149         } else {
 150                 /* Pad block to 56 bytes */
 151                 memset(p, 0, count - 8);
 152         }
 153         byteReverse(ctx->in, 14);
 154
 155         /* Append length in bits and transform */
 156         ((uint32_t *) ctx->in)[14] = ctx->bits[0];
 157         ((uint32_t *) ctx->in)[15] = ctx->bits[1];
 158
 159         MD5Transform(ctx->buf, (uint32_t *) ctx->in);
 160         byteReverse((unsigned char *) ctx->buf, 4);
 161         memcpy(digest, ctx->buf, 16);
 162         memset(ctx, 0, sizeof(ctx));    /* In case it's sensitive */
 163 }
 164
 165 #ifndef ASM_MD5
 166
 167 /* The four core functions - F1 is optimized somewhat */
 168
 169 /* #define F1(x, y, z) (x & y | ~x & z) */
 170 #define F1(x, y, z) (z ^ (x & (y ^ z)))
 171 #define F2(x, y, z) F1(z, x, y)
 172 #define F3(x, y, z) (x ^ y ^ z)
 173 #define F4(x, y, z) (y ^ (x | ~z))
 174
 175 /* This is the central step in the MD5 algorithm. */
 176 #define MD5STEP(f, w, x, y, z, data, s) \
 177         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
 178
 179 /*
 180  * The core of the MD5 algorithm, this alters an existing MD5 hash to
 181  * reflect the addition of 16 longwords of new data.  MD5Update blocks
 182  * the data and converts bytes into longwords for this routine.
 183  */
 184 void MD5Transform(uint32_t buf[4], uint32_t const in[16])
 185 {
 186         register uint32_t a, b, c, d;
 187
 188         a = buf[0];
 189         b = buf[1];
 190         c = buf[2];
 191         d = buf[3];
 192
 193         MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
 194         MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
 195         MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
 196         MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
 197         MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
 198         MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
 199         MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
 200         MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
 201         MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
 202         MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
 203         MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
 204         MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
 205         MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
 206         MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
 207         MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
 208         MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
 209
 210         MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
 211         MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
 212         MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
 213         MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
 214         MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
 215         MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
 216         MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
 217         MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
 218         MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
 219         MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
 220         MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
 221         MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
 222         MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
 223         MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
 224         MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
 225         MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
 226
 227         MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
 228         MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
 229         MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
 230         MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
 231         MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
 232         MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
 233         MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
 234         MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
 235         MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
 236         MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
 237         MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
 238         MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
 239         MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
 240         MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
 241         MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
 242         MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
 243
 244         MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
 245         MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
 246         MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
 247         MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
 248         MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
 249         MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
 250         MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
 251         MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
 252         MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
 253         MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
 254         MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
 255         MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
 256         MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
 257         MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
 258         MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
 259         MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
 260
 261         buf[0] += a;
 262         buf[1] += b;
 263         buf[2] += c;
 264         buf[3] += d;
 265 }
 266
 267 #endif