com32/libutil/md5.c

   1 /*
   2  * MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
   3  *
   4  * Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
   5  * rights reserved.
   6  *
   7  * License to copy and use this software is granted provided that it
   8  * is identified as the "RSA Data Security, Inc. MD5 Message-Digest
   9  * Algorithm" in all material mentioning or referencing this software
  10  * or this function.
  11  *
  12  * License is also granted to make and use derivative works provided
  13  * that such works are identified as "derived from the RSA Data
  14  * Security, Inc. MD5 Message-Digest Algorithm" in all material
  15  * mentioning or referencing the derived work.
  16  *
  17  * RSA Data Security, Inc. makes no representations concerning either
  18  * the merchantability of this software or the suitability of this
  19  * software for any particular purpose. It is provided "as is"
  20  * without express or implied warranty of any kind.
  21  *
  22  * These notices must be retained in any copies of any part of this
  23  * documentation and/or software.
  24  *
  25  * This code is the same as the code published by RSA Inc.  It has been
  26  * edited for clarity and style only.
  27  */
  28
  29 #include <string.h>
  30 #include <endian.h>
  31 #include <md5.h>
  32
  33 static void MD5Transform(uint32_t[4], const unsigned char[64]);
  34
  35 #define Encode memcpy
  36 #define Decode memcpy
  37
  38 static unsigned char PADDING[64] = {
  39     0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  40     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  41     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  42 };
  43
  44 /* F, G, H and I are basic MD5 functions. */
  45 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  46 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
  47 #define H(x, y, z) ((x) ^ (y) ^ (z))
  48 #define I(x, y, z) ((y) ^ ((x) | (~z)))
  49
  50 /* ROTATE_LEFT rotates x left n bits. */
  51 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  52
  53 /*
  54  * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
  55  * Rotation is separate from addition to prevent recomputation.
  56  */
  57 #define FF(a, b, c, d, x, s, ac) { \
  58         (a) += F ((b), (c), (d)) + (x) + (uint32_t)(ac); \
  59         (a) = ROTATE_LEFT ((a), (s)); \
  60         (a) += (b); \
  61         }
  62 #define GG(a, b, c, d, x, s, ac) { \
  63         (a) += G ((b), (c), (d)) + (x) + (uint32_t)(ac); \
  64         (a) = ROTATE_LEFT ((a), (s)); \
  65         (a) += (b); \
  66         }
  67 #define HH(a, b, c, d, x, s, ac) { \
  68         (a) += H ((b), (c), (d)) + (x) + (uint32_t)(ac); \
  69         (a) = ROTATE_LEFT ((a), (s)); \
  70         (a) += (b); \
  71         }
  72 #define II(a, b, c, d, x, s, ac) { \
  73         (a) += I ((b), (c), (d)) + (x) + (uint32_t)(ac); \
  74         (a) = ROTATE_LEFT ((a), (s)); \
  75         (a) += (b); \
  76         }
  77
  78 /* MD5 initialization. Begins an MD5 operation, writing a new context. */
  79
  80 void MD5Init(MD5_CTX * context)
  81 {
  82     context->count[0] = context->count[1] = 0;
  83
  84     /* Load magic initialization constants.  */
  85     context->state[0] = 0x67452301;
  86     context->state[1] = 0xefcdab89;
  87     context->state[2] = 0x98badcfe;
  88     context->state[3] = 0x10325476;
  89 }
  90
  91 /*
  92  * MD5 block update operation. Continues an MD5 message-digest
  93  * operation, processing another message block, and updating the
  94  * context.
  95  */
  96
  97 void MD5Update(MD5_CTX * context, const void *in, size_t inputLen)
  98 {
  99     unsigned int i, idx, partLen;
 100     const unsigned char *input = in;
 101
 102     /* Compute number of bytes mod 64 */
 103     idx = (unsigned int)((context->count[0] >> 3) & 0x3F);
 104
 105     /* Update number of bits */
 106     if ((context->count[0] += ((uint32_t) inputLen << 3))
 107         < ((uint32_t) inputLen << 3))
 108         context->count[1]++;
 109     context->count[1] += ((uint32_t) inputLen >> 29);
 110
 111     partLen = 64 - idx;
 112
 113     /* Transform as many times as possible. */
 114     if (inputLen >= partLen) {
 115         memcpy((void *)&context->buffer[idx], (const void *)input, partLen);
 116         MD5Transform(context->state, context->buffer);
 117
 118         for (i = partLen; i + 63 < inputLen; i += 64)
 119             MD5Transform(context->state, &input[i]);
 120
 121         idx = 0;
 122     } else
 123         i = 0;
 124
 125     /* Buffer remaining input */
 126     memcpy((void *)&context->buffer[idx], (const void *)&input[i],
 127            inputLen - i);
 128 }
 129
 130 /*
 131  * MD5 padding. Adds padding followed by original length.
 132  */
 133
 134 static void MD5Pad(MD5_CTX * context)
 135 {
 136     unsigned char bits[8];
 137     unsigned int idx, padLen;
 138
 139     /* Save number of bits */
 140     Encode(bits, context->count, 8);
 141
 142     /* Pad out to 56 mod 64. */
 143     idx = (unsigned int)((context->count[0] >> 3) & 0x3f);
 144     padLen = (idx < 56) ? (56 - idx) : (120 - idx);
 145     MD5Update(context, PADDING, padLen);
 146
 147     /* Append length (before padding) */
 148     MD5Update(context, bits, 8);
 149 }
 150
 151 /*
 152  * MD5 finalization. Ends an MD5 message-digest operation, writing the
 153  * the message digest and zeroizing the context.
 154  */
 155
 156 void MD5Final(unsigned char digest[16], MD5_CTX * context)
 157 {
 158     /* Do padding. */
 159     MD5Pad(context);
 160
 161     /* Store state in digest */
 162     Encode(digest, context->state, 16);
 163
 164     /* Zeroize sensitive information. */
 165     memset((void *)context, 0, sizeof(*context));
 166 }
 167
 168 /* MD5 basic transformation. Transforms state based on block. */
 169
 170 static void MD5Transform(state, block)
 171 uint32_t state[4];
 172 const unsigned char block[64];
 173 {
 174     uint32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 175
 176     Decode(x, block, 64);
 177
 178     /* Round 1 */
 179 #define S11 7
 180 #define S12 12
 181 #define S13 17
 182 #define S14 22
 183     FF(a, b, c, d, x[0], S11, 0xd76aa478);      /* 1 */
 184     FF(d, a, b, c, x[1], S12, 0xe8c7b756);      /* 2 */
 185     FF(c, d, a, b, x[2], S13, 0x242070db);      /* 3 */
 186     FF(b, c, d, a, x[3], S14, 0xc1bdceee);      /* 4 */
 187     FF(a, b, c, d, x[4], S11, 0xf57c0faf);      /* 5 */
 188     FF(d, a, b, c, x[5], S12, 0x4787c62a);      /* 6 */
 189     FF(c, d, a, b, x[6], S13, 0xa8304613);      /* 7 */
 190     FF(b, c, d, a, x[7], S14, 0xfd469501);      /* 8 */
 191     FF(a, b, c, d, x[8], S11, 0x698098d8);      /* 9 */
 192     FF(d, a, b, c, x[9], S12, 0x8b44f7af);      /* 10 */
 193     FF(c, d, a, b, x[10], S13, 0xffff5bb1);     /* 11 */
 194     FF(b, c, d, a, x[11], S14, 0x895cd7be);     /* 12 */
 195     FF(a, b, c, d, x[12], S11, 0x6b901122);     /* 13 */
 196     FF(d, a, b, c, x[13], S12, 0xfd987193);     /* 14 */
 197     FF(c, d, a, b, x[14], S13, 0xa679438e);     /* 15 */
 198     FF(b, c, d, a, x[15], S14, 0x49b40821);     /* 16 */
 199
 200     /* Round 2 */
 201 #define S21 5
 202 #define S22 9
 203 #define S23 14
 204 #define S24 20
 205     GG(a, b, c, d, x[1], S21, 0xf61e2562);      /* 17 */
 206     GG(d, a, b, c, x[6], S22, 0xc040b340);      /* 18 */
 207     GG(c, d, a, b, x[11], S23, 0x265e5a51);     /* 19 */
 208     GG(b, c, d, a, x[0], S24, 0xe9b6c7aa);      /* 20 */
 209     GG(a, b, c, d, x[5], S21, 0xd62f105d);      /* 21 */
 210     GG(d, a, b, c, x[10], S22, 0x2441453);      /* 22 */
 211     GG(c, d, a, b, x[15], S23, 0xd8a1e681);     /* 23 */
 212     GG(b, c, d, a, x[4], S24, 0xe7d3fbc8);      /* 24 */
 213     GG(a, b, c, d, x[9], S21, 0x21e1cde6);      /* 25 */
 214     GG(d, a, b, c, x[14], S22, 0xc33707d6);     /* 26 */
 215     GG(c, d, a, b, x[3], S23, 0xf4d50d87);      /* 27 */
 216     GG(b, c, d, a, x[8], S24, 0x455a14ed);      /* 28 */
 217     GG(a, b, c, d, x[13], S21, 0xa9e3e905);     /* 29 */
 218     GG(d, a, b, c, x[2], S22, 0xfcefa3f8);      /* 30 */
 219     GG(c, d, a, b, x[7], S23, 0x676f02d9);      /* 31 */
 220     GG(b, c, d, a, x[12], S24, 0x8d2a4c8a);     /* 32 */
 221
 222     /* Round 3 */
 223 #define S31 4
 224 #define S32 11
 225 #define S33 16
 226 #define S34 23
 227     HH(a, b, c, d, x[5], S31, 0xfffa3942);      /* 33 */
 228     HH(d, a, b, c, x[8], S32, 0x8771f681);      /* 34 */
 229     HH(c, d, a, b, x[11], S33, 0x6d9d6122);     /* 35 */
 230     HH(b, c, d, a, x[14], S34, 0xfde5380c);     /* 36 */
 231     HH(a, b, c, d, x[1], S31, 0xa4beea44);      /* 37 */
 232     HH(d, a, b, c, x[4], S32, 0x4bdecfa9);      /* 38 */
 233     HH(c, d, a, b, x[7], S33, 0xf6bb4b60);      /* 39 */
 234     HH(b, c, d, a, x[10], S34, 0xbebfbc70);     /* 40 */
 235     HH(a, b, c, d, x[13], S31, 0x289b7ec6);     /* 41 */
 236     HH(d, a, b, c, x[0], S32, 0xeaa127fa);      /* 42 */
 237     HH(c, d, a, b, x[3], S33, 0xd4ef3085);      /* 43 */
 238     HH(b, c, d, a, x[6], S34, 0x4881d05);       /* 44 */
 239     HH(a, b, c, d, x[9], S31, 0xd9d4d039);      /* 45 */
 240     HH(d, a, b, c, x[12], S32, 0xe6db99e5);     /* 46 */
 241     HH(c, d, a, b, x[15], S33, 0x1fa27cf8);     /* 47 */
 242     HH(b, c, d, a, x[2], S34, 0xc4ac5665);      /* 48 */
 243
 244     /* Round 4 */
 245 #define S41 6
 246 #define S42 10
 247 #define S43 15
 248 #define S44 21
 249     II(a, b, c, d, x[0], S41, 0xf4292244);      /* 49 */
 250     II(d, a, b, c, x[7], S42, 0x432aff97);      /* 50 */
 251     II(c, d, a, b, x[14], S43, 0xab9423a7);     /* 51 */
 252     II(b, c, d, a, x[5], S44, 0xfc93a039);      /* 52 */
 253     II(a, b, c, d, x[12], S41, 0x655b59c3);     /* 53 */
 254     II(d, a, b, c, x[3], S42, 0x8f0ccc92);      /* 54 */
 255     II(c, d, a, b, x[10], S43, 0xffeff47d);     /* 55 */
 256     II(b, c, d, a, x[1], S44, 0x85845dd1);      /* 56 */
 257     II(a, b, c, d, x[8], S41, 0x6fa87e4f);      /* 57 */
 258     II(d, a, b, c, x[15], S42, 0xfe2ce6e0);     /* 58 */
 259     II(c, d, a, b, x[6], S43, 0xa3014314);      /* 59 */
 260     II(b, c, d, a, x[13], S44, 0x4e0811a1);     /* 60 */
 261     II(a, b, c, d, x[4], S41, 0xf7537e82);      /* 61 */
 262     II(d, a, b, c, x[11], S42, 0xbd3af235);     /* 62 */
 263     II(c, d, a, b, x[2], S43, 0x2ad7d2bb);      /* 63 */
 264     II(b, c, d, a, x[9], S44, 0xeb86d391);      /* 64 */
 265
 266     state[0] += a;
 267     state[1] += b;
 268     state[2] += c;
 269     state[3] += d;
 270
 271     /* Zeroize sensitive information. */
 272     memset((void *)x, 0, sizeof(x));
 273 }