external/bsd/ntp/dist/lib/isc/md5.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (C) 2004, 2005, 2007  Internet Systems Consortium, Inc. ("ISC")
   5  * Copyright (C) 2000, 2001  Internet Software Consortium.
   6  *
   7  * Permission to use, copy, modify, and/or distribute this software for any
   8  * purpose with or without fee is hereby granted, provided that the above
   9  * copyright notice and this permission notice appear in all copies.
  10  *
  11  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  12  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  13  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  14  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  15  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  16  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  17  * PERFORMANCE OF THIS SOFTWARE.
  18  */
  19
  20 /* Id: md5.c,v 1.14 2007/06/19 23:47:17 tbox Exp */
  21
  22 /*! \file
  23  * This code implements the MD5 message-digest algorithm.
  24  * The algorithm is due to Ron Rivest.  This code was
  25  * written by Colin Plumb in 1993, no copyright is claimed.
  26  * This code is in the public domain; do with it what you wish.
  27  *
  28  * Equivalent code is available from RSA Data Security, Inc.
  29  * This code has been tested against that, and is equivalent,
  30  * except that you don't need to include two pages of legalese
  31  * with every copy.
  32  *
  33  * To compute the message digest of a chunk of bytes, declare an
  34  * MD5Context structure, pass it to MD5Init, call MD5Update as
  35  * needed on buffers full of bytes, and then call MD5Final, which
  36  * will fill a supplied 16-byte array with the digest.
  37  */
  38
  39 #include "config.h"
  40
  41 #include <isc/assertions.h>
  42 #include <isc/md5.h>
  43 #include <isc/string.h>
  44 #include <isc/types.h>
  45 #include <isc/util.h>
  46
  47 static void
  48 byteSwap(isc_uint32_t *buf, unsigned words)
  49 {
  50         unsigned char *p = (unsigned char *)buf;
  51
  52         do {
  53                 *buf++ = (isc_uint32_t)((unsigned)p[3] << 8 | p[2]) << 16 |
  54                         ((unsigned)p[1] << 8 | p[0]);
  55                 p += 4;
  56         } while (--words);
  57 }
  58
  59 /*!
  60  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
  61  * initialization constants.
  62  */
  63 void
  64 isc_md5_init(isc_md5_t *ctx) {
  65         ctx->buf[0] = 0x67452301;
  66         ctx->buf[1] = 0xefcdab89;
  67         ctx->buf[2] = 0x98badcfe;
  68         ctx->buf[3] = 0x10325476;
  69
  70         ctx->bytes[0] = 0;
  71         ctx->bytes[1] = 0;
  72 }
  73
  74 void
  75 isc_md5_invalidate(isc_md5_t *ctx) {
  76         memset(ctx, 0, sizeof(isc_md5_t));
  77 }
  78
  79 /*@{*/
  80 /*! The four core functions - F1 is optimized somewhat */
  81
  82 /* #define F1(x, y, z) (x & y | ~x & z) */
  83 #define F1(x, y, z) (z ^ (x & (y ^ z)))
  84 #define F2(x, y, z) F1(z, x, y)
  85 #define F3(x, y, z) (x ^ y ^ z)
  86 #define F4(x, y, z) (y ^ (x | ~z))
  87 /*@}*/
  88
  89 /*! This is the central step in the MD5 algorithm. */
  90 #define MD5STEP(f,w,x,y,z,in,s) \
  91          (w += f(x,y,z) + in, w = (w<<s | w>>(32-s)) + x)
  92
  93 /*!
  94  * The core of the MD5 algorithm, this alters an existing MD5 hash to
  95  * reflect the addition of 16 longwords of new data.  MD5Update blocks
  96  * the data and converts bytes into longwords for this routine.
  97  */
  98 static void
  99 transform(isc_uint32_t buf[4], isc_uint32_t const in[16]) {
 100         register isc_uint32_t a, b, c, d;
 101
 102         a = buf[0];
 103         b = buf[1];
 104         c = buf[2];
 105         d = buf[3];
 106
 107         MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
 108         MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
 109         MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
 110         MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
 111         MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
 112         MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
 113         MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
 114         MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
 115         MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
 116         MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
 117         MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
 118         MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
 119         MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
 120         MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
 121         MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
 122         MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
 123
 124         MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
 125         MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
 126         MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
 127         MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
 128         MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
 129         MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
 130         MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
 131         MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
 132         MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
 133         MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
 134         MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
 135         MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
 136         MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
 137         MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
 138         MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
 139         MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
 140
 141         MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
 142         MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
 143         MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
 144         MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
 145         MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
 146         MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
 147         MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
 148         MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
 149         MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
 150         MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
 151         MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
 152         MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
 153         MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
 154         MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
 155         MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
 156         MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
 157
 158         MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
 159         MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
 160         MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
 161         MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
 162         MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
 163         MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
 164         MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
 165         MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
 166         MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
 167         MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
 168         MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
 169         MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
 170         MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
 171         MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
 172         MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
 173         MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
 174
 175         buf[0] += a;
 176         buf[1] += b;
 177         buf[2] += c;
 178         buf[3] += d;
 179 }
 180
 181 /*!
 182  * Update context to reflect the concatenation of another buffer full
 183  * of bytes.
 184  */
 185 void
 186 isc_md5_update(isc_md5_t *ctx, const unsigned char *buf, unsigned int len) {
 187         isc_uint32_t t;
 188
 189         /* Update byte count */
 190
 191         t = ctx->bytes[0];
 192         if ((ctx->bytes[0] = t + len) < t)
 193                 ctx->bytes[1]++;        /* Carry from low to high */
 194
 195         t = 64 - (t & 0x3f);    /* Space available in ctx->in (at least 1) */
 196         if (t > len) {
 197                 memcpy((unsigned char *)ctx->in + 64 - t, buf, len);
 198                 return;
 199         }
 200         /* First chunk is an odd size */
 201         memcpy((unsigned char *)ctx->in + 64 - t, buf, t);
 202         byteSwap(ctx->in, 16);
 203         transform(ctx->buf, ctx->in);
 204         buf += t;
 205         len -= t;
 206
 207         /* Process data in 64-byte chunks */
 208         while (len >= 64) {
 209                 memcpy(ctx->in, buf, 64);
 210                 byteSwap(ctx->in, 16);
 211                 transform(ctx->buf, ctx->in);
 212                 buf += 64;
 213                 len -= 64;
 214         }
 215
 216         /* Handle any remaining bytes of data. */
 217         memcpy(ctx->in, buf, len);
 218 }
 219
 220 /*!
 221  * Final wrapup - pad to 64-byte boundary with the bit pattern
 222  * 1 0* (64-bit count of bits processed, MSB-first)
 223  */
 224 void
 225 isc_md5_final(isc_md5_t *ctx, unsigned char *digest) {
 226         int count = ctx->bytes[0] & 0x3f;    /* Number of bytes in ctx->in */
 227         unsigned char *p = (unsigned char *)ctx->in + count;
 228
 229         /* Set the first char of padding to 0x80.  There is always room. */
 230         *p++ = 0x80;
 231
 232         /* Bytes of padding needed to make 56 bytes (-8..55) */
 233         count = 56 - 1 - count;
 234
 235         if (count < 0) {        /* Padding forces an extra block */
 236                 memset(p, 0, count + 8);
 237                 byteSwap(ctx->in, 16);
 238                 transform(ctx->buf, ctx->in);
 239                 p = (unsigned char *)ctx->in;
 240                 count = 56;
 241         }
 242         memset(p, 0, count);
 243         byteSwap(ctx->in, 14);
 244
 245         /* Append length in bits and transform */
 246         ctx->in[14] = ctx->bytes[0] << 3;
 247         ctx->in[15] = ctx->bytes[1] << 3 | ctx->bytes[0] >> 29;
 248         transform(ctx->buf, ctx->in);
 249
 250         byteSwap(ctx->buf, 4);
 251         memcpy(digest, ctx->buf, 16);
 252         memset(ctx, 0, sizeof(isc_md5_t));      /* In case it's sensitive */
 253 }