masqmail-0.2

annotate src/md5/md5.c @ 184:b3835b6b834b

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Security fix! Correct handling of seteuid() return value See Debian bug #638002, reported by John Lightsey. When possible the (already available) set_euidgid() function is used. Additionally, it is unnecessary to change the identity when writing into an already open file descriptor. This should fix the problem.
author markus schnalke <meillo@marmaro.de>
date Sat, 27 Aug 2011 18:00:40 +0200
parents
children
rev   line source
meillo@162 1 /*
meillo@162 2 * This is an OpenSSL-compatible implementation of the RSA Data Security,
meillo@162 3 * Inc. MD5 Message-Digest Algorithm (RFC 1321).
meillo@162 4 *
meillo@162 5 * Written by Solar Designer <solar at openwall.com> in 2001, and placed
meillo@162 6 * in the public domain. There's absolutely no warranty.
meillo@162 7 *
meillo@162 8 * This differs from Colin Plumb's older public domain implementation in
meillo@162 9 * that no 32-bit integer data type is required, there's no compile-time
meillo@162 10 * endianness configuration, and the function prototypes match OpenSSL's.
meillo@162 11 * The primary goals are portability and ease of use.
meillo@162 12 *
meillo@162 13 * This implementation is meant to be fast, but not as fast as possible.
meillo@162 14 * Some known optimizations are not included to reduce source code size
meillo@162 15 * and avoid compile-time configuration.
meillo@162 16 */
meillo@162 17
meillo@162 18 #ifndef HAVE_OPENSSL
meillo@162 19
meillo@162 20 #include <string.h>
meillo@162 21
meillo@162 22 #include "md5.h"
meillo@162 23
meillo@162 24 /*
meillo@162 25 * The basic MD5 functions.
meillo@162 26 *
meillo@162 27 * F and G are optimized compared to their RFC 1321 definitions for
meillo@162 28 * architectures that lack an AND-NOT instruction, just like in Colin Plumb's
meillo@162 29 * implementation.
meillo@162 30 */
meillo@162 31 #define F(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
meillo@162 32 #define G(x, y, z) ((y) ^ ((z) & ((x) ^ (y))))
meillo@162 33 #define H(x, y, z) ((x) ^ (y) ^ (z))
meillo@162 34 #define I(x, y, z) ((y) ^ ((x) | ~(z)))
meillo@162 35
meillo@162 36 /*
meillo@162 37 * The MD5 transformation for all four rounds.
meillo@162 38 */
meillo@162 39 #define STEP(f, a, b, c, d, x, t, s) \
meillo@162 40 (a) += f((b), (c), (d)) + (x) + (t); \
meillo@162 41 (a) = (((a) << (s)) | (((a) & 0xffffffff) >> (32 - (s)))); \
meillo@162 42 (a) += (b);
meillo@162 43
meillo@162 44 /*
meillo@162 45 * SET reads 4 input bytes in little-endian byte order and stores them
meillo@162 46 * in a properly aligned word in host byte order.
meillo@162 47 *
meillo@162 48 * The check for little-endian architectures that tolerate unaligned
meillo@162 49 * memory accesses is just an optimization. Nothing will break if it
meillo@162 50 * doesn't work.
meillo@162 51 */
meillo@162 52 #if defined(__i386__) || defined(__x86_64__) || defined(__vax__)
meillo@162 53 #define SET(n) \
meillo@162 54 (*(MD5_u32plus *)&ptr[(n) * 4])
meillo@162 55 #define GET(n) \
meillo@162 56 SET(n)
meillo@162 57 #else
meillo@162 58 #define SET(n) \
meillo@162 59 (ctx->block[(n)] = \
meillo@162 60 (MD5_u32plus)ptr[(n) * 4] | \
meillo@162 61 ((MD5_u32plus)ptr[(n) * 4 + 1] << 8) | \
meillo@162 62 ((MD5_u32plus)ptr[(n) * 4 + 2] << 16) | \
meillo@162 63 ((MD5_u32plus)ptr[(n) * 4 + 3] << 24))
meillo@162 64 #define GET(n) \
meillo@162 65 (ctx->block[(n)])
meillo@162 66 #endif
meillo@162 67
meillo@162 68 /*
meillo@162 69 * This processes one or more 64-byte data blocks, but does NOT update
meillo@162 70 * the bit counters. There are no alignment requirements.
meillo@162 71 */
meillo@162 72 static void *body(MD5_CTX *ctx, void *data, unsigned long size)
meillo@162 73 {
meillo@162 74 unsigned char *ptr;
meillo@162 75 MD5_u32plus a, b, c, d;
meillo@162 76 MD5_u32plus saved_a, saved_b, saved_c, saved_d;
meillo@162 77
meillo@162 78 ptr = data;
meillo@162 79
meillo@162 80 a = ctx->a;
meillo@162 81 b = ctx->b;
meillo@162 82 c = ctx->c;
meillo@162 83 d = ctx->d;
meillo@162 84
meillo@162 85 do {
meillo@162 86 saved_a = a;
meillo@162 87 saved_b = b;
meillo@162 88 saved_c = c;
meillo@162 89 saved_d = d;
meillo@162 90
meillo@162 91 /* Round 1 */
meillo@162 92 STEP(F, a, b, c, d, SET(0), 0xd76aa478, 7)
meillo@162 93 STEP(F, d, a, b, c, SET(1), 0xe8c7b756, 12)
meillo@162 94 STEP(F, c, d, a, b, SET(2), 0x242070db, 17)
meillo@162 95 STEP(F, b, c, d, a, SET(3), 0xc1bdceee, 22)
meillo@162 96 STEP(F, a, b, c, d, SET(4), 0xf57c0faf, 7)
meillo@162 97 STEP(F, d, a, b, c, SET(5), 0x4787c62a, 12)
meillo@162 98 STEP(F, c, d, a, b, SET(6), 0xa8304613, 17)
meillo@162 99 STEP(F, b, c, d, a, SET(7), 0xfd469501, 22)
meillo@162 100 STEP(F, a, b, c, d, SET(8), 0x698098d8, 7)
meillo@162 101 STEP(F, d, a, b, c, SET(9), 0x8b44f7af, 12)
meillo@162 102 STEP(F, c, d, a, b, SET(10), 0xffff5bb1, 17)
meillo@162 103 STEP(F, b, c, d, a, SET(11), 0x895cd7be, 22)
meillo@162 104 STEP(F, a, b, c, d, SET(12), 0x6b901122, 7)
meillo@162 105 STEP(F, d, a, b, c, SET(13), 0xfd987193, 12)
meillo@162 106 STEP(F, c, d, a, b, SET(14), 0xa679438e, 17)
meillo@162 107 STEP(F, b, c, d, a, SET(15), 0x49b40821, 22)
meillo@162 108
meillo@162 109 /* Round 2 */
meillo@162 110 STEP(G, a, b, c, d, GET(1), 0xf61e2562, 5)
meillo@162 111 STEP(G, d, a, b, c, GET(6), 0xc040b340, 9)
meillo@162 112 STEP(G, c, d, a, b, GET(11), 0x265e5a51, 14)
meillo@162 113 STEP(G, b, c, d, a, GET(0), 0xe9b6c7aa, 20)
meillo@162 114 STEP(G, a, b, c, d, GET(5), 0xd62f105d, 5)
meillo@162 115 STEP(G, d, a, b, c, GET(10), 0x02441453, 9)
meillo@162 116 STEP(G, c, d, a, b, GET(15), 0xd8a1e681, 14)
meillo@162 117 STEP(G, b, c, d, a, GET(4), 0xe7d3fbc8, 20)
meillo@162 118 STEP(G, a, b, c, d, GET(9), 0x21e1cde6, 5)
meillo@162 119 STEP(G, d, a, b, c, GET(14), 0xc33707d6, 9)
meillo@162 120 STEP(G, c, d, a, b, GET(3), 0xf4d50d87, 14)
meillo@162 121 STEP(G, b, c, d, a, GET(8), 0x455a14ed, 20)
meillo@162 122 STEP(G, a, b, c, d, GET(13), 0xa9e3e905, 5)
meillo@162 123 STEP(G, d, a, b, c, GET(2), 0xfcefa3f8, 9)
meillo@162 124 STEP(G, c, d, a, b, GET(7), 0x676f02d9, 14)
meillo@162 125 STEP(G, b, c, d, a, GET(12), 0x8d2a4c8a, 20)
meillo@162 126
meillo@162 127 /* Round 3 */
meillo@162 128 STEP(H, a, b, c, d, GET(5), 0xfffa3942, 4)
meillo@162 129 STEP(H, d, a, b, c, GET(8), 0x8771f681, 11)
meillo@162 130 STEP(H, c, d, a, b, GET(11), 0x6d9d6122, 16)
meillo@162 131 STEP(H, b, c, d, a, GET(14), 0xfde5380c, 23)
meillo@162 132 STEP(H, a, b, c, d, GET(1), 0xa4beea44, 4)
meillo@162 133 STEP(H, d, a, b, c, GET(4), 0x4bdecfa9, 11)
meillo@162 134 STEP(H, c, d, a, b, GET(7), 0xf6bb4b60, 16)
meillo@162 135 STEP(H, b, c, d, a, GET(10), 0xbebfbc70, 23)
meillo@162 136 STEP(H, a, b, c, d, GET(13), 0x289b7ec6, 4)
meillo@162 137 STEP(H, d, a, b, c, GET(0), 0xeaa127fa, 11)
meillo@162 138 STEP(H, c, d, a, b, GET(3), 0xd4ef3085, 16)
meillo@162 139 STEP(H, b, c, d, a, GET(6), 0x04881d05, 23)
meillo@162 140 STEP(H, a, b, c, d, GET(9), 0xd9d4d039, 4)
meillo@162 141 STEP(H, d, a, b, c, GET(12), 0xe6db99e5, 11)
meillo@162 142 STEP(H, c, d, a, b, GET(15), 0x1fa27cf8, 16)
meillo@162 143 STEP(H, b, c, d, a, GET(2), 0xc4ac5665, 23)
meillo@162 144
meillo@162 145 /* Round 4 */
meillo@162 146 STEP(I, a, b, c, d, GET(0), 0xf4292244, 6)
meillo@162 147 STEP(I, d, a, b, c, GET(7), 0x432aff97, 10)
meillo@162 148 STEP(I, c, d, a, b, GET(14), 0xab9423a7, 15)
meillo@162 149 STEP(I, b, c, d, a, GET(5), 0xfc93a039, 21)
meillo@162 150 STEP(I, a, b, c, d, GET(12), 0x655b59c3, 6)
meillo@162 151 STEP(I, d, a, b, c, GET(3), 0x8f0ccc92, 10)
meillo@162 152 STEP(I, c, d, a, b, GET(10), 0xffeff47d, 15)
meillo@162 153 STEP(I, b, c, d, a, GET(1), 0x85845dd1, 21)
meillo@162 154 STEP(I, a, b, c, d, GET(8), 0x6fa87e4f, 6)
meillo@162 155 STEP(I, d, a, b, c, GET(15), 0xfe2ce6e0, 10)
meillo@162 156 STEP(I, c, d, a, b, GET(6), 0xa3014314, 15)
meillo@162 157 STEP(I, b, c, d, a, GET(13), 0x4e0811a1, 21)
meillo@162 158 STEP(I, a, b, c, d, GET(4), 0xf7537e82, 6)
meillo@162 159 STEP(I, d, a, b, c, GET(11), 0xbd3af235, 10)
meillo@162 160 STEP(I, c, d, a, b, GET(2), 0x2ad7d2bb, 15)
meillo@162 161 STEP(I, b, c, d, a, GET(9), 0xeb86d391, 21)
meillo@162 162
meillo@162 163 a += saved_a;
meillo@162 164 b += saved_b;
meillo@162 165 c += saved_c;
meillo@162 166 d += saved_d;
meillo@162 167
meillo@162 168 ptr += 64;
meillo@162 169 } while (size -= 64);
meillo@162 170
meillo@162 171 ctx->a = a;
meillo@162 172 ctx->b = b;
meillo@162 173 ctx->c = c;
meillo@162 174 ctx->d = d;
meillo@162 175
meillo@162 176 return ptr;
meillo@162 177 }
meillo@162 178
meillo@162 179 void MD5_Init(MD5_CTX *ctx)
meillo@162 180 {
meillo@162 181 ctx->a = 0x67452301;
meillo@162 182 ctx->b = 0xefcdab89;
meillo@162 183 ctx->c = 0x98badcfe;
meillo@162 184 ctx->d = 0x10325476;
meillo@162 185
meillo@162 186 ctx->lo = 0;
meillo@162 187 ctx->hi = 0;
meillo@162 188 }
meillo@162 189
meillo@162 190 void MD5_Update(MD5_CTX *ctx, void *data, unsigned long size)
meillo@162 191 {
meillo@162 192 MD5_u32plus saved_lo;
meillo@162 193 unsigned long used, free;
meillo@162 194
meillo@162 195 saved_lo = ctx->lo;
meillo@162 196 if ((ctx->lo = (saved_lo + size) & 0x1fffffff) < saved_lo)
meillo@162 197 ctx->hi++;
meillo@162 198 ctx->hi += size >> 29;
meillo@162 199
meillo@162 200 used = saved_lo & 0x3f;
meillo@162 201
meillo@162 202 if (used) {
meillo@162 203 free = 64 - used;
meillo@162 204
meillo@162 205 if (size < free) {
meillo@162 206 memcpy(&ctx->buffer[used], data, size);
meillo@162 207 return;
meillo@162 208 }
meillo@162 209
meillo@162 210 memcpy(&ctx->buffer[used], data, free);
meillo@162 211 data = (unsigned char *)data + free;
meillo@162 212 size -= free;
meillo@162 213 body(ctx, ctx->buffer, 64);
meillo@162 214 }
meillo@162 215
meillo@162 216 if (size >= 64) {
meillo@162 217 data = body(ctx, data, size & ~(unsigned long)0x3f);
meillo@162 218 size &= 0x3f;
meillo@162 219 }
meillo@162 220
meillo@162 221 memcpy(ctx->buffer, data, size);
meillo@162 222 }
meillo@162 223
meillo@162 224 void MD5_Final(unsigned char *result, MD5_CTX *ctx)
meillo@162 225 {
meillo@162 226 unsigned long used, free;
meillo@162 227
meillo@162 228 used = ctx->lo & 0x3f;
meillo@162 229
meillo@162 230 ctx->buffer[used++] = 0x80;
meillo@162 231
meillo@162 232 free = 64 - used;
meillo@162 233
meillo@162 234 if (free < 8) {
meillo@162 235 memset(&ctx->buffer[used], 0, free);
meillo@162 236 body(ctx, ctx->buffer, 64);
meillo@162 237 used = 0;
meillo@162 238 free = 64;
meillo@162 239 }
meillo@162 240
meillo@162 241 memset(&ctx->buffer[used], 0, free - 8);
meillo@162 242
meillo@162 243 ctx->lo <<= 3;
meillo@162 244 ctx->buffer[56] = ctx->lo;
meillo@162 245 ctx->buffer[57] = ctx->lo >> 8;
meillo@162 246 ctx->buffer[58] = ctx->lo >> 16;
meillo@162 247 ctx->buffer[59] = ctx->lo >> 24;
meillo@162 248 ctx->buffer[60] = ctx->hi;
meillo@162 249 ctx->buffer[61] = ctx->hi >> 8;
meillo@162 250 ctx->buffer[62] = ctx->hi >> 16;
meillo@162 251 ctx->buffer[63] = ctx->hi >> 24;
meillo@162 252
meillo@162 253 body(ctx, ctx->buffer, 64);
meillo@162 254
meillo@162 255 result[0] = ctx->a;
meillo@162 256 result[1] = ctx->a >> 8;
meillo@162 257 result[2] = ctx->a >> 16;
meillo@162 258 result[3] = ctx->a >> 24;
meillo@162 259 result[4] = ctx->b;
meillo@162 260 result[5] = ctx->b >> 8;
meillo@162 261 result[6] = ctx->b >> 16;
meillo@162 262 result[7] = ctx->b >> 24;
meillo@162 263 result[8] = ctx->c;
meillo@162 264 result[9] = ctx->c >> 8;
meillo@162 265 result[10] = ctx->c >> 16;
meillo@162 266 result[11] = ctx->c >> 24;
meillo@162 267 result[12] = ctx->d;
meillo@162 268 result[13] = ctx->d >> 8;
meillo@162 269 result[14] = ctx->d >> 16;
meillo@162 270 result[15] = ctx->d >> 24;
meillo@162 271
meillo@162 272 memset(ctx, 0, sizeof(*ctx));
meillo@162 273 }
meillo@162 274
meillo@162 275 #endif