mono/utils/mono-md5.c

   1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
   2 /*
   3  * This code implements the MD5 message-digest algorithm.
   4  * The algorithm is due to Ron Rivest.  This code was
   5  * written by Colin Plumb in 1993, no copyright is claimed.
   6  * This code is in the public domain; do with it what you wish.
   7  *
   8  * Equivalent code is available from RSA Data Security, Inc.
   9  * This code has been tested against that, and is equivalent,
  10  * except that you don't need to include two pages of legalese
  11  * with every copy.
  12  *
  13  * To compute the message digest of a chunk of bytes, declare an
  14  * MonoMD5Context structure, pass it to mono_md5_init, call mono_md5_update as
  15  * needed on buffers full of bytes, and then call md5_Final, which
  16  * will fill a supplied 16-byte array with the digest.
  17  */
  18
  19 /* parts of this file are :
  20  * Written March 1993 by Branko Lankester
  21  * Modified June 1993 by Colin Plumb for altered md5.c.
  22  * Modified October 1995 by Erik Troan for RPM
  23  */
  24
  25
  26 #include <stdio.h>
  27 #include <string.h>
  28 #include "mono-digest.h"
  29
  30 static void md5_transform (guint32 buf[4], const guint32 in[16]);
  31
  32 static gint _ie = 0x44332211;
  33 static union _endian { gint i; gchar b[4]; } *_endian = (union _endian *)&_ie;
  34 #define IS_BIG_ENDIAN()         (_endian->b[0] == '\x44')
  35 #define IS_LITTLE_ENDIAN()      (_endian->b[0] == '\x11')
  36
  37
  38 /*
  39  * Note: this code is harmless on little-endian machines.
  40  */
  41 static void
  42 _byte_reverse (guchar *buf, guint32 longs)
  43 {
  44         guint32 t;
  45         do {
  46                 t = (guint32) ((guint32) buf[3] << 8 | buf[2]) << 16 |
  47                         ((guint32) buf[1] << 8 | buf[0]);
  48                 *(guint32 *) buf = t;
  49                 buf += 4;
  50         } while (--longs);
  51 }
  52
  53 /**
  54  * mono_md5_init: Initialise an md5 context object
  55  * @ctx: md5 context
  56  *
  57  * Initialise an md5 buffer.
  58  *
  59  **/
  60 void
  61 mono_md5_init (MonoMD5Context *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         if (IS_BIG_ENDIAN())
  72                 ctx->doByteReverse = 1;
  73         else
  74                 ctx->doByteReverse = 0;
  75 }
  76
  77
  78
  79 /**
  80  * mono_md5_update: add a buffer to md5 hash computation
  81  * @ctx: conetxt object used for md5 computaion
  82  * @buf: buffer to add
  83  * @len: buffer length
  84  *
  85  * Update context to reflect the concatenation of another buffer full
  86  * of bytes. Use this to progressively construct an md5 hash.
  87  **/
  88 void
  89 mono_md5_update (MonoMD5Context *ctx, const guchar *buf, guint32 len)
  90 {
  91         guint32 t;
  92
  93         /* Update bitcount */
  94
  95         t = ctx->bits[0];
  96         if ((ctx->bits[0] = t + ((guint32) len << 3)) < t)
  97                 ctx->bits[1]++;         /* Carry from low to high */
  98         ctx->bits[1] += len >> 29;
  99
 100         t = (t >> 3) & 0x3f;    /* Bytes already in shsInfo->data */
 101
 102         /* Handle any leading odd-sized chunks */
 103
 104         if (t) {
 105                 guchar *p = (guchar *) ctx->in + t;
 106
 107                 t = 64 - t;
 108                 if (len < t) {
 109                         memcpy (p, buf, len);
 110                         return;
 111                 }
 112                 memcpy (p, buf, t);
 113                 if (ctx->doByteReverse)
 114                         _byte_reverse (ctx->in, 16);
 115                 md5_transform (ctx->buf, (guint32 *) ctx->in);
 116                 buf += t;
 117                 len -= t;
 118         }
 119         /* Process data in 64-byte chunks */
 120
 121         while (len >= 64) {
 122                 memcpy (ctx->in, buf, 64);
 123                 if (ctx->doByteReverse)
 124                         _byte_reverse (ctx->in, 16);
 125                 md5_transform (ctx->buf, (guint32 *) ctx->in);
 126                 buf += 64;
 127                 len -= 64;
 128         }
 129
 130         /* Handle any remaining bytes of data. */
 131
 132         memcpy (ctx->in, buf, len);
 133 }
 134
 135
 136
 137
 138
 139 /*
 140  * Final wrapup - pad to 64-byte boundary with the bit pattern
 141  * 1 0* (64-bit count of bits processed, MSB-first)
 142  */
 143 /**
 144  * mono_md5_final: copy the final md5 hash to a bufer
 145  * @digest: 16 bytes buffer
 146  * @ctx: context containing the calculated md5
 147  *
 148  * copy the final md5 hash to a bufer
 149  **/
 150 void
 151 mono_md5_final (MonoMD5Context *ctx, guchar digest[16])
 152 {
 153         guint32 count;
 154         guchar *p;
 155
 156         /* Compute number of bytes mod 64 */
 157         count = (ctx->bits[0] >> 3) & 0x3F;
 158
 159         /* Set the first char of padding to 0x80.  This is safe since there is
 160            always at least one byte free */
 161         p = ctx->in + count;
 162         *p++ = 0x80;
 163
 164         /* Bytes of padding needed to make 64 bytes */
 165         count = 64 - 1 - count;
 166
 167         /* Pad out to 56 mod 64 */
 168         if (count < 8) {
 169                 /* Two lots of padding:  Pad the first block to 64 bytes */
 170                 memset (p, 0, count);
 171                 if (ctx->doByteReverse)
 172                         _byte_reverse (ctx->in, 16);
 173                 md5_transform (ctx->buf, (guint32 *) ctx->in);
 174
 175                 /* Now fill the next block with 56 bytes */
 176                 memset (ctx->in, 0, 56);
 177         } else {
 178                 /* Pad block to 56 bytes */
 179                 memset (p, 0, count - 8);
 180         }
 181         if (ctx->doByteReverse)
 182                 _byte_reverse (ctx->in, 14);
 183
 184         /* Append length in bits and transform */
 185         ((guint32 *) ctx->in)[14] = ctx->bits[0];
 186         ((guint32 *) ctx->in)[15] = ctx->bits[1];
 187
 188         md5_transform (ctx->buf, (guint32 *) ctx->in);
 189         if (ctx->doByteReverse)
 190                 _byte_reverse ((guchar *) ctx->buf, 4);
 191         memcpy (digest, ctx->buf, 16);
 192 }
 193
 194
 195
 196
 197 /* The four core functions - F1 is optimized somewhat */
 198
 199 /* #define F1(x, y, z) (x & y | ~x & z) */
 200 #define F1(x, y, z) (z ^ (x & (y ^ z)))
 201 #define F2(x, y, z) F1(z, x, y)
 202 #define F3(x, y, z) (x ^ y ^ z)
 203 #define F4(x, y, z) (y ^ (x | ~z))
 204
 205 /* This is the central step in the MD5 algorithm. */
 206 #define MD5STEP(f, w, x, y, z, data, s) \
 207         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
 208
 209 /*
 210  * The core of the MD5 algorithm, this alters an existing MD5 hash to
 211  * reflect the addition of 16 longwords of new data.  md5_Update blocks
 212  * the data and converts bytes into longwords for this routine.
 213  */
 214 static void
 215 md5_transform (guint32 buf[4], const guint32 in[16])
 216 {
 217         register guint32 a, b, c, d;
 218
 219         a = buf[0];
 220         b = buf[1];
 221         c = buf[2];
 222         d = buf[3];
 223
 224         MD5STEP (F1, a, b, c, d, in[0] + 0xd76aa478, 7);
 225         MD5STEP (F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
 226         MD5STEP (F1, c, d, a, b, in[2] + 0x242070db, 17);
 227         MD5STEP (F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
 228         MD5STEP (F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
 229         MD5STEP (F1, d, a, b, c, in[5] + 0x4787c62a, 12);
 230         MD5STEP (F1, c, d, a, b, in[6] + 0xa8304613, 17);
 231         MD5STEP (F1, b, c, d, a, in[7] + 0xfd469501, 22);
 232         MD5STEP (F1, a, b, c, d, in[8] + 0x698098d8, 7);
 233         MD5STEP (F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
 234         MD5STEP (F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
 235         MD5STEP (F1, b, c, d, a, in[11] + 0x895cd7be, 22);
 236         MD5STEP (F1, a, b, c, d, in[12] + 0x6b901122, 7);
 237         MD5STEP (F1, d, a, b, c, in[13] + 0xfd987193, 12);
 238         MD5STEP (F1, c, d, a, b, in[14] + 0xa679438e, 17);
 239         MD5STEP (F1, b, c, d, a, in[15] + 0x49b40821, 22);
 240
 241         MD5STEP (F2, a, b, c, d, in[1] + 0xf61e2562, 5);
 242         MD5STEP (F2, d, a, b, c, in[6] + 0xc040b340, 9);
 243         MD5STEP (F2, c, d, a, b, in[11] + 0x265e5a51, 14);
 244         MD5STEP (F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
 245         MD5STEP (F2, a, b, c, d, in[5] + 0xd62f105d, 5);
 246         MD5STEP (F2, d, a, b, c, in[10] + 0x02441453, 9);
 247         MD5STEP (F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
 248         MD5STEP (F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
 249         MD5STEP (F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
 250         MD5STEP (F2, d, a, b, c, in[14] + 0xc33707d6, 9);
 251         MD5STEP (F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
 252         MD5STEP (F2, b, c, d, a, in[8] + 0x455a14ed, 20);
 253         MD5STEP (F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
 254         MD5STEP (F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
 255         MD5STEP (F2, c, d, a, b, in[7] + 0x676f02d9, 14);
 256         MD5STEP (F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
 257
 258         MD5STEP (F3, a, b, c, d, in[5] + 0xfffa3942, 4);
 259         MD5STEP (F3, d, a, b, c, in[8] + 0x8771f681, 11);
 260         MD5STEP (F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
 261         MD5STEP (F3, b, c, d, a, in[14] + 0xfde5380c, 23);
 262         MD5STEP (F3, a, b, c, d, in[1] + 0xa4beea44, 4);
 263         MD5STEP (F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
 264         MD5STEP (F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
 265         MD5STEP (F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
 266         MD5STEP (F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
 267         MD5STEP (F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
 268         MD5STEP (F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
 269         MD5STEP (F3, b, c, d, a, in[6] + 0x04881d05, 23);
 270         MD5STEP (F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
 271         MD5STEP (F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
 272         MD5STEP (F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
 273         MD5STEP (F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
 274
 275         MD5STEP (F4, a, b, c, d, in[0] + 0xf4292244, 6);
 276         MD5STEP (F4, d, a, b, c, in[7] + 0x432aff97, 10);
 277         MD5STEP (F4, c, d, a, b, in[14] + 0xab9423a7, 15);
 278         MD5STEP (F4, b, c, d, a, in[5] + 0xfc93a039, 21);
 279         MD5STEP (F4, a, b, c, d, in[12] + 0x655b59c3, 6);
 280         MD5STEP (F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
 281         MD5STEP (F4, c, d, a, b, in[10] + 0xffeff47d, 15);
 282         MD5STEP (F4, b, c, d, a, in[1] + 0x85845dd1, 21);
 283         MD5STEP (F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
 284         MD5STEP (F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
 285         MD5STEP (F4, c, d, a, b, in[6] + 0xa3014314, 15);
 286         MD5STEP (F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
 287         MD5STEP (F4, a, b, c, d, in[4] + 0xf7537e82, 6);
 288         MD5STEP (F4, d, a, b, c, in[11] + 0xbd3af235, 10);
 289         MD5STEP (F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
 290         MD5STEP (F4, b, c, d, a, in[9] + 0xeb86d391, 21);
 291
 292         buf[0] += a;
 293         buf[1] += b;
 294         buf[2] += c;
 295         buf[3] += d;
 296 }
 297
 298
 299
 300
 301 /**
 302  * mono_md5_get_digest: get the md5 hash of a buffer
 303  * @buffer: byte buffer
 304  * @buffer_size: buffer size (in bytes)
 305  * @digest: 16 bytes buffer receiving the hash code.
 306  *
 307  * Get the md5 hash of a buffer. The result is put in
 308  * the 16 bytes buffer @digest .
 309  **/
 310 void
 311 mono_md5_get_digest (const guchar *buffer, gint buffer_size, guchar digest[16])
 312 {
 313         MonoMD5Context ctx;
 314
 315         mono_md5_init (&ctx);
 316         mono_md5_update (&ctx, buffer, buffer_size);
 317         mono_md5_final (&ctx, digest);
 318
 319 }
 320
 321
 322 /**
 323  * mono_md5_get_digest_from_file: get the md5 hash of a file
 324  * @filename: file name
 325  * @digest: 16 bytes buffer receiving the hash code.
 326  *
 327  * Get the md5 hash of a file. The result is put in
 328  * the 16 bytes buffer @digest .
 329  *
 330  * If an IO error happens the value in @digest is not updated.
 331  **/
 332 void
 333 mono_md5_get_digest_from_file (const gchar *filename, guchar digest[16])
 334 {
 335         MonoMD5Context ctx;
 336         guchar tmp_buf[1024];
 337         gint nb_bytes_read;
 338         FILE *fp;
 339
 340         mono_md5_init (&ctx);
 341         fp = fopen(filename, "r");
 342         if (!fp) {
 343                 return;
 344         }
 345
 346         while ((nb_bytes_read = fread (tmp_buf, sizeof (guchar), 1024, fp)) > 0)
 347                 mono_md5_update (&ctx, tmp_buf, nb_bytes_read);
 348
 349         if (ferror(fp)) {
 350                 fclose(fp);
 351                 return;
 352         } else {
 353                 fclose(fp);
 354         }
 355
 356         mono_md5_final (&ctx, digest);
 357 }
 358
 359
 360
 361