dlls/advapi32/crypt_md5.c

   1 /*
   2  * Copyright (C) 2001 Nikos Mavroyanopoulos
   3  * Copyright (C) 2004 Hans Leidekker
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  18  */
  19
  20 /*
  21  * This code implements the MD5 message-digest algorithm.
  22  * It is based on code in the public domain written by Colin
  23  * Plumb in 1993. The algorithm is due to Ron Rivest.
  24  *
  25  * Equivalent code is available from RSA Data Security, Inc.
  26  * This code has been tested against that, and is equivalent,
  27  * except that you don't need to include two pages of legalese
  28  * with every copy.
  29  *
  30  * To compute the message digest of a chunk of bytes, declare an
  31  * MD5_CTX structure, pass it to MD5Init, call MD5Update as
  32  * needed on buffers full of bytes, and then call MD5Final, which
  33  * will fill a supplied 16-byte array with the digest.
  34  */
  35
  36 #include <stdarg.h>
  37
  38 #include "windef.h"
  39
  40 typedef struct
  41 {
  42     unsigned int i[2];
  43     unsigned int buf[4];
  44     unsigned char in[64];
  45     unsigned char digest[16];
  46 } MD5_CTX;
  47
  48 static void MD5Transform( unsigned int buf[4], const unsigned int in[16] );
  49
  50 /*
  51  * Note: this code is harmless on little-endian machines.
  52  */
  53 static void byteReverse( unsigned char *buf, unsigned longs )
  54 {
  55     unsigned int t;
  56
  57     do {
  58         t = ((unsigned)buf[3] << 8 | buf[2]) << 16 |
  59             ((unsigned)buf[1] << 8 | buf[0]);
  60         *(unsigned int *)buf = t;
  61         buf += 4;
  62     } while (--longs);
  63 }
  64
  65 /*
  66  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
  67  * initialization constants.
  68  */
  69 VOID WINAPI MD5Init( MD5_CTX *ctx )
  70 {
  71     ctx->buf[0] = 0x67452301;
  72     ctx->buf[1] = 0xefcdab89;
  73     ctx->buf[2] = 0x98badcfe;
  74     ctx->buf[3] = 0x10325476;
  75
  76     ctx->i[0] = ctx->i[1] = 0;
  77 }
  78
  79 /*
  80  * Update context to reflect the concatenation of another buffer full
  81  * of bytes.
  82  */
  83 VOID WINAPI MD5Update( MD5_CTX *ctx, const unsigned char *buf, unsigned int len )
  84 {
  85     register unsigned int t;
  86
  87     /* Update bitcount */
  88     t = ctx->i[0];
  89
  90     if ((ctx->i[0] = t + (len << 3)) < t)
  91         ctx->i[1]++;        /* Carry from low to high */
  92
  93     ctx->i[1] += len >> 29;
  94     t = (t >> 3) & 0x3f;
  95
  96     /* Handle any leading odd-sized chunks */
  97     if (t)
  98     {
  99         unsigned char *p = (unsigned char *)ctx->in + t;
 100         t = 64 - t;
 101
 102         if (len < t)
 103         {
 104             memcpy( p, buf, len );
 105             return;
 106         }
 107
 108         memcpy( p, buf, t );
 109         byteReverse( ctx->in, 16 );
 110
 111         MD5Transform( ctx->buf, (unsigned int *)ctx->in );
 112
 113         buf += t;
 114         len -= t;
 115     }
 116
 117     /* Process data in 64-byte chunks */
 118     while (len >= 64)
 119     {
 120         memcpy( ctx->in, buf, 64 );
 121         byteReverse( ctx->in, 16 );
 122
 123         MD5Transform( ctx->buf, (unsigned int *)ctx->in );
 124
 125         buf += 64;
 126         len -= 64;
 127     }
 128
 129     /* Handle any remaining bytes of data. */
 130     memcpy( ctx->in, buf, len );
 131 }
 132
 133 /*
 134  * Final wrapup - pad to 64-byte boundary with the bit pattern
 135  * 1 0* (64-bit count of bits processed, MSB-first)
 136  */
 137 VOID WINAPI MD5Final( MD5_CTX *ctx )
 138 {
 139     unsigned int count;
 140     unsigned char *p;
 141
 142     /* Compute number of bytes mod 64 */
 143     count = (ctx->i[0] >> 3) & 0x3F;
 144
 145     /* Set the first char of padding to 0x80.  This is safe since there is
 146        always at least one byte free */
 147     p = ctx->in + count;
 148     *p++ = 0x80;
 149
 150     /* Bytes of padding needed to make 64 bytes */
 151     count = 64 - 1 - count;
 152
 153     /* Pad out to 56 mod 64 */
 154     if (count < 8)
 155     {
 156         /* Two lots of padding:  Pad the first block to 64 bytes */
 157         memset( p, 0, count );
 158         byteReverse( ctx->in, 16 );
 159         MD5Transform( ctx->buf, (unsigned int *)ctx->in );
 160
 161         /* Now fill the next block with 56 bytes */
 162         memset( ctx->in, 0, 56 );
 163     }
 164     else
 165     {
 166         /* Pad block to 56 bytes */
 167         memset( p, 0, count - 8 );
 168     }
 169
 170     byteReverse( ctx->in, 14 );
 171
 172     /* Append length in bits and transform */
 173     ((unsigned int *)ctx->in)[14] = ctx->i[0];
 174     ((unsigned int *)ctx->in)[15] = ctx->i[1];
 175
 176     MD5Transform( ctx->buf, (unsigned int *)ctx->in );
 177     byteReverse( (unsigned char *)ctx->buf, 4 );
 178     memcpy( ctx->digest, ctx->buf, 16 );
 179 }
 180
 181 /* The four core functions - F1 is optimized somewhat */
 182
 183 /* #define F1( x, y, z ) (x & y | ~x & z) */
 184 #define F1( x, y, z ) (z ^ (x & (y ^ z)))
 185 #define F2( x, y, z ) F1( z, x, y )
 186 #define F3( x, y, z ) (x ^ y ^ z)
 187 #define F4( x, y, z ) (y ^ (x | ~z))
 188
 189 /* This is the central step in the MD5 algorithm. */
 190 #define MD5STEP( f, w, x, y, z, data, s ) \
 191         ( w += f( x, y, z ) + data,  w = w << s | w >> (32 - s),  w += x )
 192
 193 /*
 194  * The core of the MD5 algorithm, this alters an existing MD5 hash to
 195  * reflect the addition of 16 longwords of new data.  MD5Update blocks
 196  * the data and converts bytes into longwords for this routine.
 197  */
 198 static void MD5Transform( unsigned int buf[4], const unsigned int in[16] )
 199 {
 200     register unsigned int a, b, c, d;
 201
 202     a = buf[0];
 203     b = buf[1];
 204     c = buf[2];
 205     d = buf[3];
 206
 207     MD5STEP( F1, a, b, c, d, in[0] + 0xd76aa478, 7 );
 208     MD5STEP( F1, d, a, b, c, in[1] + 0xe8c7b756, 12 );
 209     MD5STEP( F1, c, d, a, b, in[2] + 0x242070db, 17 );
 210     MD5STEP( F1, b, c, d, a, in[3] + 0xc1bdceee, 22 );
 211     MD5STEP( F1, a, b, c, d, in[4] + 0xf57c0faf, 7 );
 212     MD5STEP( F1, d, a, b, c, in[5] + 0x4787c62a, 12 );
 213     MD5STEP( F1, c, d, a, b, in[6] + 0xa8304613, 17 );
 214     MD5STEP( F1, b, c, d, a, in[7] + 0xfd469501, 22 );
 215     MD5STEP( F1, a, b, c, d, in[8] + 0x698098d8, 7 );
 216     MD5STEP( F1, d, a, b, c, in[9] + 0x8b44f7af, 12 );
 217     MD5STEP( F1, c, d, a, b, in[10] + 0xffff5bb1, 17 );
 218     MD5STEP( F1, b, c, d, a, in[11] + 0x895cd7be, 22 );
 219     MD5STEP( F1, a, b, c, d, in[12] + 0x6b901122, 7 );
 220     MD5STEP( F1, d, a, b, c, in[13] + 0xfd987193, 12 );
 221     MD5STEP( F1, c, d, a, b, in[14] + 0xa679438e, 17 );
 222     MD5STEP( F1, b, c, d, a, in[15] + 0x49b40821, 22 );
 223
 224     MD5STEP( F2, a, b, c, d, in[1] + 0xf61e2562, 5 );
 225     MD5STEP( F2, d, a, b, c, in[6] + 0xc040b340, 9 );
 226     MD5STEP( F2, c, d, a, b, in[11] + 0x265e5a51, 14 );
 227     MD5STEP( F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20 );
 228     MD5STEP( F2, a, b, c, d, in[5] + 0xd62f105d, 5 );
 229     MD5STEP( F2, d, a, b, c, in[10] + 0x02441453, 9 );
 230     MD5STEP( F2, c, d, a, b, in[15] + 0xd8a1e681, 14 );
 231     MD5STEP( F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20 );
 232     MD5STEP( F2, a, b, c, d, in[9] + 0x21e1cde6, 5 );
 233     MD5STEP( F2, d, a, b, c, in[14] + 0xc33707d6, 9 );
 234     MD5STEP( F2, c, d, a, b, in[3] + 0xf4d50d87, 14 );
 235     MD5STEP( F2, b, c, d, a, in[8] + 0x455a14ed, 20 );
 236     MD5STEP( F2, a, b, c, d, in[13] + 0xa9e3e905, 5 );
 237     MD5STEP( F2, d, a, b, c, in[2] + 0xfcefa3f8, 9 );
 238     MD5STEP( F2, c, d, a, b, in[7] + 0x676f02d9, 14 );
 239     MD5STEP( F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20 );
 240
 241     MD5STEP( F3, a, b, c, d, in[5] + 0xfffa3942, 4 );
 242     MD5STEP( F3, d, a, b, c, in[8] + 0x8771f681, 11 );
 243     MD5STEP( F3, c, d, a, b, in[11] + 0x6d9d6122, 16 );
 244     MD5STEP( F3, b, c, d, a, in[14] + 0xfde5380c, 23 );
 245     MD5STEP( F3, a, b, c, d, in[1] + 0xa4beea44, 4 );
 246     MD5STEP( F3, d, a, b, c, in[4] + 0x4bdecfa9, 11 );
 247     MD5STEP( F3, c, d, a, b, in[7] + 0xf6bb4b60, 16 );
 248     MD5STEP( F3, b, c, d, a, in[10] + 0xbebfbc70, 23 );
 249     MD5STEP( F3, a, b, c, d, in[13] + 0x289b7ec6, 4 );
 250     MD5STEP( F3, d, a, b, c, in[0] + 0xeaa127fa, 11 );
 251     MD5STEP( F3, c, d, a, b, in[3] + 0xd4ef3085, 16 );
 252     MD5STEP( F3, b, c, d, a, in[6] + 0x04881d05, 23 );
 253     MD5STEP( F3, a, b, c, d, in[9] + 0xd9d4d039, 4 );
 254     MD5STEP( F3, d, a, b, c, in[12] + 0xe6db99e5, 11 );
 255     MD5STEP( F3, c, d, a, b, in[15] + 0x1fa27cf8, 16 );
 256     MD5STEP( F3, b, c, d, a, in[2] + 0xc4ac5665, 23 );
 257
 258     MD5STEP( F4, a, b, c, d, in[0] + 0xf4292244, 6 );
 259     MD5STEP( F4, d, a, b, c, in[7] + 0x432aff97, 10 );
 260     MD5STEP( F4, c, d, a, b, in[14] + 0xab9423a7, 15 );
 261     MD5STEP( F4, b, c, d, a, in[5] + 0xfc93a039, 21 );
 262     MD5STEP( F4, a, b, c, d, in[12] + 0x655b59c3, 6 );
 263     MD5STEP( F4, d, a, b, c, in[3] + 0x8f0ccc92, 10 );
 264     MD5STEP( F4, c, d, a, b, in[10] + 0xffeff47d, 15 );
 265     MD5STEP( F4, b, c, d, a, in[1] + 0x85845dd1, 21 );
 266     MD5STEP( F4, a, b, c, d, in[8] + 0x6fa87e4f, 6 );
 267     MD5STEP( F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10 );
 268     MD5STEP( F4, c, d, a, b, in[6] + 0xa3014314, 15 );
 269     MD5STEP( F4, b, c, d, a, in[13] + 0x4e0811a1, 21 );
 270     MD5STEP( F4, a, b, c, d, in[4] + 0xf7537e82, 6 );
 271     MD5STEP( F4, d, a, b, c, in[11] + 0xbd3af235, 10 );
 272     MD5STEP( F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15 );
 273     MD5STEP( F4, b, c, d, a, in[9] + 0xeb86d391, 21 );
 274
 275     buf[0] += a;
 276     buf[1] += b;
 277     buf[2] += c;
 278     buf[3] += d;
 279 }