Annotation of embedaddon/ntp/lib/isc/md5.c, revision 1.1.1.1

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

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