root/crypto/md5.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. MD5Init
  2. MD5Update
  3. MD5Final
  4. MD5Transform

    1 /*      $OpenBSD: md5.c,v 1.1 2004/05/07 14:42:26 millert Exp $ */
    2 
    3 /*
    4  * This code implements the MD5 message-digest algorithm.
    5  * The algorithm is due to Ron Rivest.  This code was
    6  * written by Colin Plumb in 1993, no copyright is claimed.
    7  * This code is in the public domain; do with it what you wish.
    8  *
    9  * Equivalent code is available from RSA Data Security, Inc.
   10  * This code has been tested against that, and is equivalent,
   11  * except that you don't need to include two pages of legalese
   12  * with every copy.
   13  *
   14  * To compute the message digest of a chunk of bytes, declare an
   15  * MD5Context structure, pass it to MD5Init, call MD5Update as
   16  * needed on buffers full of bytes, and then call MD5Final, which
   17  * will fill a supplied 16-byte array with the digest.
   18  */
   19 
   20 #include <sys/param.h>
   21 #include <sys/systm.h>
   22 #include <crypto/md5.h>
   23 
   24 #define PUT_64BIT_LE(cp, value) do {                                    \
   25         (cp)[7] = (value) >> 56;                                        \
   26         (cp)[6] = (value) >> 48;                                        \
   27         (cp)[5] = (value) >> 40;                                        \
   28         (cp)[4] = (value) >> 32;                                        \
   29         (cp)[3] = (value) >> 24;                                        \
   30         (cp)[2] = (value) >> 16;                                        \
   31         (cp)[1] = (value) >> 8;                                         \
   32         (cp)[0] = (value); } while (0)
   33 
   34 #define PUT_32BIT_LE(cp, value) do {                                    \
   35         (cp)[3] = (value) >> 24;                                        \
   36         (cp)[2] = (value) >> 16;                                        \
   37         (cp)[1] = (value) >> 8;                                         \
   38         (cp)[0] = (value); } while (0)
   39 
   40 static u_int8_t PADDING[MD5_BLOCK_LENGTH] = {
   41         0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
   42         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
   43         0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
   44 };
   45 
   46 /*
   47  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
   48  * initialization constants.
   49  */
   50 void
   51 MD5Init(MD5_CTX *ctx)
   52 {
   53         ctx->count = 0;
   54         ctx->state[0] = 0x67452301;
   55         ctx->state[1] = 0xefcdab89;
   56         ctx->state[2] = 0x98badcfe;
   57         ctx->state[3] = 0x10325476;
   58 }
   59 
   60 /*
   61  * Update context to reflect the concatenation of another buffer full
   62  * of bytes.
   63  */
   64 void
   65 MD5Update(MD5_CTX *ctx, const unsigned char *input, size_t len)
   66 {
   67         size_t have, need;
   68 
   69         /* Check how many bytes we already have and how many more we need. */
   70         have = (size_t)((ctx->count >> 3) & (MD5_BLOCK_LENGTH - 1));
   71         need = MD5_BLOCK_LENGTH - have;
   72 
   73         /* Update bitcount */
   74         ctx->count += (u_int64_t)len << 3;
   75 
   76         if (len >= need) {
   77                 if (have != 0) {
   78                         bcopy(input, ctx->buffer + have, need);
   79                         MD5Transform(ctx->state, ctx->buffer);
   80                         input += need;
   81                         len -= need;
   82                         have = 0;
   83                 }
   84 
   85                 /* Process data in MD5_BLOCK_LENGTH-byte chunks. */
   86                 while (len >= MD5_BLOCK_LENGTH) {
   87                         MD5Transform(ctx->state, input);
   88                         input += MD5_BLOCK_LENGTH;
   89                         len -= MD5_BLOCK_LENGTH;
   90                 }
   91         }
   92 
   93         /* Handle any remaining bytes of data. */
   94         if (len != 0)
   95                 bcopy(input, ctx->buffer + have, len);
   96 }
   97 
   98 /*
   99  * Final wrapup - pad to 64-byte boundary with the bit pattern
  100  * 1 0* (64-bit count of bits processed, MSB-first)
  101  */
  102 void
  103 MD5Final(unsigned char digest[MD5_DIGEST_LENGTH], MD5_CTX *ctx)
  104 {
  105         u_int8_t count[8];
  106         size_t padlen;
  107         int i;
  108 
  109         /* Convert count to 8 bytes in little endian order. */
  110         PUT_64BIT_LE(count, ctx->count);
  111 
  112         /* Pad out to 56 mod 64. */
  113         padlen = MD5_BLOCK_LENGTH -
  114             ((ctx->count >> 3) & (MD5_BLOCK_LENGTH - 1));
  115         if (padlen < 1 + 8)
  116                 padlen += MD5_BLOCK_LENGTH;
  117         MD5Update(ctx, PADDING, padlen - 8);            /* padlen - 8 <= 64 */
  118         MD5Update(ctx, count, 8);
  119 
  120         if (digest != NULL) {
  121                 for (i = 0; i < 4; i++)
  122                         PUT_32BIT_LE(digest + i * 4, ctx->state[i]);
  123         }
  124         bzero(ctx, sizeof(*ctx));       /* in case it's sensitive */
  125 }
  126 
  127 
  128 /* The four core functions - F1 is optimized somewhat */
  129 
  130 /* #define F1(x, y, z) (x & y | ~x & z) */
  131 #define F1(x, y, z) (z ^ (x & (y ^ z)))
  132 #define F2(x, y, z) F1(z, x, y)
  133 #define F3(x, y, z) (x ^ y ^ z)
  134 #define F4(x, y, z) (y ^ (x | ~z))
  135 
  136 /* This is the central step in the MD5 algorithm. */
  137 #define MD5STEP(f, w, x, y, z, data, s) \
  138         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
  139 
  140 /*
  141  * The core of the MD5 algorithm, this alters an existing MD5 hash to
  142  * reflect the addition of 16 longwords of new data.  MD5Update blocks
  143  * the data and converts bytes into longwords for this routine.
  144  */
  145 void
  146 MD5Transform(u_int32_t state[4], const u_int8_t block[MD5_BLOCK_LENGTH])
  147 {
  148         u_int32_t a, b, c, d, in[MD5_BLOCK_LENGTH / 4];
  149 
  150 #if BYTE_ORDER == LITTLE_ENDIAN
  151         bcopy(block, in, sizeof(in));
  152 #else
  153         for (a = 0; a < MD5_BLOCK_LENGTH / 4; a++) {
  154                 in[a] = (u_int32_t)(
  155                     (u_int32_t)(block[a * 4 + 0]) |
  156                     (u_int32_t)(block[a * 4 + 1]) <<  8 |
  157                     (u_int32_t)(block[a * 4 + 2]) << 16 |
  158                     (u_int32_t)(block[a * 4 + 3]) << 24);
  159         }
  160 #endif
  161 
  162         a = state[0];
  163         b = state[1];
  164         c = state[2];
  165         d = state[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         state[0] += a;
  236         state[1] += b;
  237         state[2] += c;
  238         state[3] += d;
  239 }

/* [<][>][^][v][top][bottom][index][help] */