lib/libmd/md5c.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  * $FreeBSD: src/lib/libmd/md5c.c,v 1.17 2006/01/17 15:35:56 phk Exp $
  26  *
  27  * This code is the same as the code published by RSA Inc.  It has been
  28  * edited for clarity and style only.
  29  */
  30
  31 #include <sys/types.h>
  32
  33 #ifdef _KERNEL
  34 #include <sys/systm.h>
  35 #else
  36 #include <string.h>
  37 #endif
  38
  39 #include <machine/endian.h>
  40 #include <sys/endian.h>
  41 #include <sys/md5.h>
  42
  43 #ifdef _KERNEL
  44 #define memset(x,y,z)   bzero(x,z);
  45 #define memcpy(x,y,z)   bcopy(y, x, z)
  46 #endif
  47
  48 #if (BYTE_ORDER == LITTLE_ENDIAN)
  49 #define Encode memcpy
  50 #define Decode memcpy
  51 #else
  52
  53 /*
  54  * Encodes input (u_int32_t) into output (unsigned char). Assumes len is
  55  * a multiple of 4.
  56  */
  57
  58 static void
  59 Encode (unsigned char *output, u_int32_t *input, unsigned int len)
  60 {
  61         unsigned int i;
  62         u_int32_t *op = (u_int32_t *)output;
  63
  64         for (i = 0; i < len / 4; i++)
  65                 op[i] = htole32(input[i]);
  66 }
  67
  68 /*
  69  * Decodes input (unsigned char) into output (u_int32_t). Assumes len is
  70  * a multiple of 4.
  71  */
  72
  73 static void
  74 Decode (u_int32_t *output, const unsigned char *input, unsigned int len)
  75 {
  76         unsigned int i;
  77         const u_int32_t *ip = (const u_int32_t *)input;
  78
  79         for (i = 0; i < len / 4; i++)
  80                 output[i] = le32toh(ip[i]);
  81 }
  82 #endif
  83
  84 static unsigned char PADDING[64] = {
  85   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  86   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  87   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  88 };
  89
  90 /* F, G, H and I are basic MD5 functions. */
  91 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  92 #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
  93 #define H(x, y, z) ((x) ^ (y) ^ (z))
  94 #define I(x, y, z) ((y) ^ ((x) | (~z)))
  95
  96 /* ROTATE_LEFT rotates x left n bits. */
  97 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  98
  99 /*
 100  * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
 101  * Rotation is separate from addition to prevent recomputation.
 102  */
 103 #define FF(a, b, c, d, x, s, ac) { \
 104         (a) += F ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 105         (a) = ROTATE_LEFT ((a), (s)); \
 106         (a) += (b); \
 107         }
 108 #define GG(a, b, c, d, x, s, ac) { \
 109         (a) += G ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 110         (a) = ROTATE_LEFT ((a), (s)); \
 111         (a) += (b); \
 112         }
 113 #define HH(a, b, c, d, x, s, ac) { \
 114         (a) += H ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 115         (a) = ROTATE_LEFT ((a), (s)); \
 116         (a) += (b); \
 117         }
 118 #define II(a, b, c, d, x, s, ac) { \
 119         (a) += I ((b), (c), (d)) + (x) + (u_int32_t)(ac); \
 120         (a) = ROTATE_LEFT ((a), (s)); \
 121         (a) += (b); \
 122         }
 123
 124 /* MD5 initialization. Begins an MD5 operation, writing a new context. */
 125
 126 int
 127 MD5Init (MD5_CTX *context)
 128 {
 129
 130         context->Nl = context->Nh = 0;
 131
 132         /* Load magic initialization constants.  */
 133         context->A = 0x67452301;
 134         context->B = 0xefcdab89;
 135         context->C = 0x98badcfe;
 136         context->D = 0x10325476;
 137         return 1;
 138 }
 139
 140 /*
 141  * MD5 block update operation. Continues an MD5 message-digest
 142  * operation, processing another message block, and updating the
 143  * context.
 144  */
 145
 146 void
 147 MD5Update (MD5_CTX *context, const void *in, unsigned int inputLen)
 148 {
 149         unsigned int i, idx, partLen;
 150         const unsigned char *input = in;
 151
 152         /* Compute number of bytes mod 64 */
 153         idx = (unsigned int)((context->Nl >> 3) & 0x3F);
 154
 155         /* Update number of bits */
 156         if ((context->Nl += ((u_int32_t)inputLen << 3))
 157             < ((u_int32_t)inputLen << 3))
 158                 context->Nh++;
 159         context->Nh += ((u_int32_t)inputLen >> 29);
 160
 161         partLen = 64 - idx;
 162
 163         /* Transform as many times as possible. */
 164         if (inputLen >= partLen) {
 165                 memcpy(&((char *)context->data)[idx], (const void *)input,
 166                     partLen);
 167                 MD5Transform (&context->A, (char *)context->data);
 168
 169                 for (i = partLen; i + 63 < inputLen; i += 64)
 170                         MD5Transform (&context->A, &input[i]);
 171
 172                 idx = 0;
 173         }
 174         else
 175                 i = 0;
 176
 177         /* Buffer remaining input */
 178         memcpy (&((char *)context->data)[idx], (const void *)&input[i],
 179             inputLen-i);
 180 }
 181
 182 /*
 183  * MD5 padding. Adds padding followed by original length.
 184  */
 185
 186 void
 187 MD5Pad (MD5_CTX *context)
 188 {
 189         unsigned char bits[8];
 190         unsigned int idx, padLen;
 191
 192         /* Save number of bits */
 193         Encode (bits, &context->Nl, 8);
 194
 195         /* Pad out to 56 mod 64. */
 196         idx = (unsigned int)((context->Nl >> 3) & 0x3f);
 197         padLen = (idx < 56) ? (56 - idx) : (120 - idx);
 198         MD5Update (context, PADDING, padLen);
 199
 200         /* Append length (before padding) */
 201         MD5Update (context, bits, 8);
 202 }
 203
 204 /*
 205  * MD5 finalization. Ends an MD5 message-digest operation, writing the
 206  * the message digest and zeroizing the context.
 207  */
 208
 209 void
 210 MD5Final (unsigned char digest[16], MD5_CTX *context)
 211 {
 212         /* Do padding. */
 213         MD5Pad (context);
 214
 215         /* Store state in digest */
 216         Encode (digest, &context->A, 16);
 217
 218         /* Zeroize sensitive information. */
 219         memset ((void *)context, 0, sizeof (*context));
 220 }
 221
 222 /* MD5 basic transformation. Transforms state based on block. */
 223
 224 void
 225 MD5Transform (u_int32_t *state, const unsigned char *block)
 226 {
 227         u_int32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
 228
 229         Decode (x, block, 64);
 230
 231         /* Round 1 */
 232 #define S11 7
 233 #define S12 12
 234 #define S13 17
 235 #define S14 22
 236         FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
 237         FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
 238         FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
 239         FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
 240         FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
 241         FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
 242         FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
 243         FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
 244         FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
 245         FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
 246         FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
 247         FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
 248         FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
 249         FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
 250         FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
 251         FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
 252
 253         /* Round 2 */
 254 #define S21 5
 255 #define S22 9
 256 #define S23 14
 257 #define S24 20
 258         GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
 259         GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
 260         GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
 261         GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
 262         GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
 263         GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
 264         GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
 265         GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
 266         GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
 267         GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
 268         GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
 269         GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
 270         GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
 271         GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
 272         GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
 273         GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
 274
 275         /* Round 3 */
 276 #define S31 4
 277 #define S32 11
 278 #define S33 16
 279 #define S34 23
 280         HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
 281         HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
 282         HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
 283         HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
 284         HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
 285         HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
 286         HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
 287         HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
 288         HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
 289         HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
 290         HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
 291         HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
 292         HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
 293         HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
 294         HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
 295         HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
 296
 297         /* Round 4 */
 298 #define S41 6
 299 #define S42 10
 300 #define S43 15
 301 #define S44 21
 302         II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
 303         II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
 304         II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
 305         II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
 306         II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
 307         II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
 308         II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
 309         II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
 310         II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
 311         II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
 312         II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
 313         II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
 314         II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
 315         II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
 316         II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
 317         II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
 318
 319         state[0] += a;
 320         state[1] += b;
 321         state[2] += c;
 322         state[3] += d;
 323
 324         /* Zeroize sensitive information. */
 325         memset ((void *)x, 0, sizeof (x));
 326 }