lib_generic/md5.c

   1 /*
   2  * This file was transplanted with slight modifications from Linux sources
   3  * (fs/cifs/md5.c) into U-Boot by Bartlomiej Sieka <tur@semihalf.com>.
   4  */
   5
   6 /*
   7  * This code implements the MD5 message-digest algorithm.
   8  * The algorithm is due to Ron Rivest.  This code was
   9  * written by Colin Plumb in 1993, no copyright is claimed.
  10  * This code is in the public domain; do with it what you wish.
  11  *
  12  * Equivalent code is available from RSA Data Security, Inc.
  13  * This code has been tested against that, and is equivalent,
  14  * except that you don't need to include two pages of legalese
  15  * with every copy.
  16  *
  17  * To compute the message digest of a chunk of bytes, declare an
  18  * MD5Context structure, pass it to MD5Init, call MD5Update as
  19  * needed on buffers full of bytes, and then call MD5Final, which
  20  * will fill a supplied 16-byte array with the digest.
  21  */
  22
  23 /* This code slightly modified to fit into Samba by
  24    abartlet@samba.org Jun 2001
  25    and to fit the cifs vfs by
  26    Steve French sfrench@us.ibm.com */
  27
  28 #include <linux/types.h>
  29 #include <linux/string.h>
  30 #include <md5.h>
  31
  32 static void
  33 MD5Transform(__u32 buf[4], __u32 const in[16]);
  34
  35 /*
  36  * Note: this code is harmless on little-endian machines.
  37  */
  38 static void
  39 byteReverse(unsigned char *buf, unsigned longs)
  40 {
  41         __u32 t;
  42         do {
  43                 t = (__u32) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
  44                     ((unsigned) buf[1] << 8 | buf[0]);
  45                 *(__u32 *) buf = t;
  46                 buf += 4;
  47         } while (--longs);
  48 }
  49
  50 /*
  51  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
  52  * initialization constants.
  53  */
  54 static void
  55 MD5Init(struct MD5Context *ctx)
  56 {
  57         ctx->buf[0] = 0x67452301;
  58         ctx->buf[1] = 0xefcdab89;
  59         ctx->buf[2] = 0x98badcfe;
  60         ctx->buf[3] = 0x10325476;
  61
  62         ctx->bits[0] = 0;
  63         ctx->bits[1] = 0;
  64 }
  65
  66 /*
  67  * Update context to reflect the concatenation of another buffer full
  68  * of bytes.
  69  */
  70 static void
  71 MD5Update(struct MD5Context *ctx, unsigned char const *buf, unsigned len)
  72 {
  73         register __u32 t;
  74
  75         /* Update bitcount */
  76
  77         t = ctx->bits[0];
  78         if ((ctx->bits[0] = t + ((__u32) len << 3)) < t)
  79                 ctx->bits[1]++; /* Carry from low to high */
  80         ctx->bits[1] += len >> 29;
  81
  82         t = (t >> 3) & 0x3f;    /* Bytes already in shsInfo->data */
  83
  84         /* Handle any leading odd-sized chunks */
  85
  86         if (t) {
  87                 unsigned char *p = (unsigned char *) ctx->in + t;
  88
  89                 t = 64 - t;
  90                 if (len < t) {
  91                         memmove(p, buf, len);
  92                         return;
  93                 }
  94                 memmove(p, buf, t);
  95                 byteReverse(ctx->in, 16);
  96                 MD5Transform(ctx->buf, (__u32 *) ctx->in);
  97                 buf += t;
  98                 len -= t;
  99         }
 100         /* Process data in 64-byte chunks */
 101
 102         while (len >= 64) {
 103                 memmove(ctx->in, buf, 64);
 104                 byteReverse(ctx->in, 16);
 105                 MD5Transform(ctx->buf, (__u32 *) ctx->in);
 106                 buf += 64;
 107                 len -= 64;
 108         }
 109
 110         /* Handle any remaining bytes of data. */
 111
 112         memmove(ctx->in, buf, len);
 113 }
 114
 115 /*
 116  * Final wrapup - pad to 64-byte boundary with the bit pattern
 117  * 1 0* (64-bit count of bits processed, MSB-first)
 118  */
 119 static void
 120 MD5Final(unsigned char digest[16], struct MD5Context *ctx)
 121 {
 122         unsigned int count;
 123         unsigned char *p;
 124
 125         /* Compute number of bytes mod 64 */
 126         count = (ctx->bits[0] >> 3) & 0x3F;
 127
 128         /* Set the first char of padding to 0x80.  This is safe since there is
 129            always at least one byte free */
 130         p = ctx->in + count;
 131         *p++ = 0x80;
 132
 133         /* Bytes of padding needed to make 64 bytes */
 134         count = 64 - 1 - count;
 135
 136         /* Pad out to 56 mod 64 */
 137         if (count < 8) {
 138                 /* Two lots of padding:  Pad the first block to 64 bytes */
 139                 memset(p, 0, count);
 140                 byteReverse(ctx->in, 16);
 141                 MD5Transform(ctx->buf, (__u32 *) ctx->in);
 142
 143                 /* Now fill the next block with 56 bytes */
 144                 memset(ctx->in, 0, 56);
 145         } else {
 146                 /* Pad block to 56 bytes */
 147                 memset(p, 0, count - 8);
 148         }
 149         byteReverse(ctx->in, 14);
 150
 151         /* Append length in bits and transform */
 152         ((__u32 *) ctx->in)[14] = ctx->bits[0];
 153         ((__u32 *) ctx->in)[15] = ctx->bits[1];
 154
 155         MD5Transform(ctx->buf, (__u32 *) ctx->in);
 156         byteReverse((unsigned char *) ctx->buf, 4);
 157         memmove(digest, ctx->buf, 16);
 158         memset(ctx, 0, sizeof(*ctx));   /* In case it's sensitive */
 159 }
 160
 161 /* The four core functions - F1 is optimized somewhat */
 162
 163 /* #define F1(x, y, z) (x & y | ~x & z) */
 164 #define F1(x, y, z) (z ^ (x & (y ^ z)))
 165 #define F2(x, y, z) F1(z, x, y)
 166 #define F3(x, y, z) (x ^ y ^ z)
 167 #define F4(x, y, z) (y ^ (x | ~z))
 168
 169 /* This is the central step in the MD5 algorithm. */
 170 #define MD5STEP(f, w, x, y, z, data, s) \
 171         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
 172
 173 /*
 174  * The core of the MD5 algorithm, this alters an existing MD5 hash to
 175  * reflect the addition of 16 longwords of new data.  MD5Update blocks
 176  * the data and converts bytes into longwords for this routine.
 177  */
 178 static void
 179 MD5Transform(__u32 buf[4], __u32 const in[16])
 180 {
 181         register __u32 a, b, c, d;
 182
 183         a = buf[0];
 184         b = buf[1];
 185         c = buf[2];
 186         d = buf[3];
 187
 188         MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
 189         MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
 190         MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
 191         MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
 192         MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
 193         MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
 194         MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
 195         MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
 196         MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
 197         MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
 198         MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
 199         MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
 200         MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
 201         MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
 202         MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
 203         MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
 204
 205         MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
 206         MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
 207         MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
 208         MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
 209         MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
 210         MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
 211         MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
 212         MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
 213         MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
 214         MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
 215         MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
 216         MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
 217         MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
 218         MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
 219         MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
 220         MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
 221
 222         MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
 223         MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
 224         MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
 225         MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
 226         MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
 227         MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
 228         MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
 229         MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
 230         MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
 231         MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
 232         MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
 233         MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
 234         MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
 235         MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
 236         MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
 237         MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
 238
 239         MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
 240         MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
 241         MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
 242         MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
 243         MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
 244         MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
 245         MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
 246         MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
 247         MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
 248         MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
 249         MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
 250         MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
 251         MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
 252         MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
 253         MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
 254         MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
 255
 256         buf[0] += a;
 257         buf[1] += b;
 258         buf[2] += c;
 259         buf[3] += d;
 260 }
 261
 262 /*
 263  * Calculate and store in 'output' the MD5 digest of 'len' bytes at
 264  * 'input'. 'output' must have enough space to hold 16 bytes.
 265  */
 266 void
 267 md5 (unsigned char *input, int len, unsigned char output[16])
 268 {
 269         struct MD5Context context;
 270
 271         MD5Init(&context);
 272         MD5Update(&context, input, len);
 273         MD5Final(output, &context);
 274 }