ircd/ircd_md5.c

   1 /*
   2  * IRC - Internet Relay Chat, ircd/ircd_md5.h
   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  * ircuified 2002 by hikari
  20  */
  21 /** @file
  22  * @brief MD5 implementation for ircu.
  23  * @version $Id: ircd_md5.c,v 1.4 2004/10/05 22:51:47 entrope Exp $
  24  */
  25
  26 #include <string.h>
  27 #include "ircd_md5.h"
  28
  29 #ifndef HIGHFIRST
  30 /** Bit-reverse bytes in a buffer. */
  31 #define byteReverse(buf, len)   /* Nothing */
  32 #else
  33 static void byteReverse(unsigned char *buf, unsigned longs);
  34
  35 #ifndef ASM_MD5
  36 /*
  37  * Note: this code is harmless on little-endian machines.
  38  */
  39 static void byteReverse(unsigned char *buf, unsigned longs)
  40 {
  41         uint32 t;
  42         do {
  43                 t = (uint32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
  44                     ((unsigned) buf[1] << 8 | buf[0]);
  45                 *(uint32 *) buf = t;
  46                 buf += 4;
  47         } while (--longs);
  48 }
  49 #endif
  50 #endif
  51
  52 /** Iniitalize MD5 context.
  53  * @param[out] ctx MD5 context to initialize.
  54  */
  55 void MD5Init(struct MD5Context *ctx)
  56 {
  57         ctx->buf[0] = 0x67452301U;
  58         ctx->buf[1] = 0xefcdab89U;
  59         ctx->buf[2] = 0x98badcfeU;
  60         ctx->buf[3] = 0x10325476U;
  61
  62         ctx->bits[0] = 0;
  63         ctx->bits[1] = 0;
  64 }
  65
  66 /** Update MD5 context with data from a buffer.
  67  * @param[in,out] ctx MD5 context to operate on.
  68  * @param[in] buf Input buffer.
  69  * @param[in] len Number of bytes in input buffer.
  70  */
  71 void MD5Update(struct MD5Context *ctx, unsigned const char *buf, unsigned len)
  72 {
  73         uint32 t;
  74
  75         /* Update bitcount */
  76
  77         t = ctx->bits[0];
  78         if ((ctx->bits[0] = t + ((uint32) len << 3)) < t)
  79                 ctx->bits[1]++; /* Carry from low to high */
  80         ctx->bits[1] += len >> 29;
  81
  82         t = (t >> 3) & 0x3f;    /* Bytes already in shsInfo->data */
  83
  84         /* Handle any leading odd-sized chunks */
  85
  86         if (t) {
  87                 unsigned char *p = (unsigned char *) ctx->in + t;
  88
  89                 t = 64 - t;
  90                 if (len < t) {
  91                         memcpy(p, buf, len);
  92                         return;
  93                 }
  94                 memcpy(p, buf, t);
  95                 byteReverse(ctx->in, 16);
  96                 MD5Transform(ctx->buf, (uint32 *) ctx->in);
  97                 buf += t;
  98                 len -= t;
  99         }
 100         /* Process data in 64-byte chunks */
 101
 102         while (len >= 64) {
 103                 memcpy(ctx->in, buf, 64);
 104                 byteReverse(ctx->in, 16);
 105                 MD5Transform(ctx->buf, (uint32 *) ctx->in);
 106                 buf += 64;
 107                 len -= 64;
 108         }
 109
 110         /* Handle any remaining bytes of data. */
 111
 112         memcpy(ctx->in, buf, len);
 113 }
 114
 115 /** Perform final steps of MD5 hash.
 116  * @param[out] digest Receives output hash value.
 117  * @param[in,out] ctx MD5 context to finalize.
 118  */
 119 void MD5Final(unsigned char digest[16], struct MD5Context *ctx)
 120 {
 121         unsigned count;
 122         unsigned char *p;
 123
 124         /* Compute number of bytes mod 64 */
 125         count = (ctx->bits[0] >> 3) & 0x3F;
 126
 127         /* Set the first char of padding to 0x80.  This is safe since there is
 128            always at least one byte free */
 129         p = ctx->in + count;
 130         *p++ = 0x80;
 131
 132         /* Bytes of padding needed to make 64 bytes */
 133         count = 64 - 1 - count;
 134
 135         /* Pad out to 56 mod 64 */
 136         if (count < 8) {
 137                 /* Two lots of padding:  Pad the first block to 64 bytes */
 138                 memset(p, 0, count);
 139                 byteReverse(ctx->in, 16);
 140                 MD5Transform(ctx->buf, (uint32 *) ctx->in);
 141
 142                 /* Now fill the next block with 56 bytes */
 143                 memset(ctx->in, 0, 56);
 144         } else {
 145                 /* Pad block to 56 bytes */
 146                 memset(p, 0, count - 8);
 147         }
 148         byteReverse(ctx->in, 14);
 149
 150         /* Append length in bits and transform */
 151         ((uint32 *) ctx->in)[14] = ctx->bits[0];
 152         ((uint32 *) ctx->in)[15] = ctx->bits[1];
 153
 154         MD5Transform(ctx->buf, (uint32 *) ctx->in);
 155         byteReverse((unsigned char *) ctx->buf, 4);
 156         memcpy(digest, ctx->buf, 16);
 157         memset(ctx, 0, sizeof(ctx));    /* In case it's sensitive */
 158 }
 159
 160 #ifndef ASM_MD5
 161
 162 /* The four core functions - F1 is optimized somewhat */
 163
 164 /* #define F1(x, y, z) (x & y | ~x & z) */
 165 /** Helper function for first round of MD5. */
 166 #define F1(x, y, z) (z ^ (x & (y ^ z)))
 167 /** Helper function for second round of MD5. */
 168 #define F2(x, y, z) F1(z, x, y)
 169 /** Helper function for third round of MD5. */
 170 #define F3(x, y, z) (x ^ y ^ z)
 171 /** Helper function for fourth round of MD5. */
 172 #define F4(x, y, z) (y ^ (x | ~z))
 173
 174 /** Step function for each round of MD5 */
 175 #define MD5STEP(f, w, x, y, z, data, s) \
 176         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
 177
 178 /** Perform the core MD5 update steps to update a 128-bit hash value
 179  * with 512 bits of input data.
 180  * @param[in,out] buf Hash value.
 181  * @param[in] in Input buffer.
 182  */
 183 void MD5Transform(uint32 buf[4], uint32 const in[16])
 184 {
 185         register uint32 a, b, c, d;
 186
 187         a = buf[0];
 188         b = buf[1];
 189         c = buf[2];
 190         d = buf[3];
 191
 192         MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478U, 7);
 193         MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756U, 12);
 194         MD5STEP(F1, c, d, a, b, in[2] + 0x242070dbU, 17);
 195         MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceeeU, 22);
 196         MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0fafU, 7);
 197         MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62aU, 12);
 198         MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613U, 17);
 199         MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501U, 22);
 200         MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8U, 7);
 201         MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7afU, 12);
 202         MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1U, 17);
 203         MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7beU, 22);
 204         MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122U, 7);
 205         MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193U, 12);
 206         MD5STEP(F1, c, d, a, b, in[14] + 0xa679438eU, 17);
 207         MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821U, 22);
 208
 209         MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562U, 5);
 210         MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340U, 9);
 211         MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51U, 14);
 212         MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aaU, 20);
 213         MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105dU, 5);
 214         MD5STEP(F2, d, a, b, c, in[10] + 0x02441453U, 9);
 215         MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681U, 14);
 216         MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8U, 20);
 217         MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6U, 5);
 218         MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6U, 9);
 219         MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87U, 14);
 220         MD5STEP(F2, b, c, d, a, in[8] + 0x455a14edU, 20);
 221         MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905U, 5);
 222         MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8U, 9);
 223         MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9U, 14);
 224         MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8aU, 20);
 225
 226         MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942U, 4);
 227         MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681U, 11);
 228         MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122U, 16);
 229         MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380cU, 23);
 230         MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44U, 4);
 231         MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9U, 11);
 232         MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60U, 16);
 233         MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70U, 23);
 234         MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6U, 4);
 235         MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127faU, 11);
 236         MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085U, 16);
 237         MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05U, 23);
 238         MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039U, 4);
 239         MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5U, 11);
 240         MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8U, 16);
 241         MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665U, 23);
 242
 243         MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244U, 6);
 244         MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97U, 10);
 245         MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7U, 15);
 246         MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039U, 21);
 247         MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3U, 6);
 248         MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92U, 10);
 249         MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47dU, 15);
 250         MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1U, 21);
 251         MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4fU, 6);
 252         MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0U, 10);
 253         MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314U, 15);
 254         MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1U, 21);
 255         MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82U, 6);
 256         MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235U, 10);
 257         MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bbU, 15);
 258         MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391U, 21);
 259
 260         buf[0] += a;
 261         buf[1] += b;
 262         buf[2] += c;
 263         buf[3] += d;
 264 }
 265
 266 #endif