openwrt/target/linux/package/bcm43xx-standalone/fwcutter/md5.c

   1 /*
   2  * This code implements the MD5 message-digest algorithm.
   3  * The algorithm is due to Ron Rivest.  This code was
   4  * written by Colin Plumb in 1993, no copyright is claimed.
   5  * This code is in the public domain; do with it what you wish.
   6  *
   7  * Equivalent code is available from RSA Data Security, Inc.
   8  * This code has been tested against that, and is equivalent,
   9  * except that you don't need to include two pages of legalese
  10  * with every copy.
  11  *
  12  * To compute the message digest of a chunk of bytes, declare an
  13  * MD5Context structure, pass it to MD5Init, call MD5Update as
  14  * needed on buffers full of bytes, and then call MD5Final, which
  15  * will fill a supplied 16-byte array with the digest.
  16  */
  17
  18 /* Brutally hacked by John Walker back from ANSI C to K&R (no
  19    prototypes) to maintain the tradition that Netfone will compile
  20    with Sun's original "cc". */
  21 /* Ripped out ugly K&R again ;) --mbuesch */
  22
  23 #include <memory.h>              /* for memcpy() */
  24 #include "md5.h"
  25
  26 extern int big_endian_cpu;
  27
  28 /*
  29  * Note: this code is harmless on little-endian machines,
  30  *       but we return early nevertheless.
  31  */
  32 static void byteReverse(unsigned char *buf, unsigned longs)
  33 {
  34     uint32_t t;
  35
  36     if (!big_endian_cpu)
  37         return;
  38
  39     do {
  40         t = (uint32_t) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
  41             ((unsigned) buf[1] << 8 | buf[0]);
  42         *(uint32_t *) buf = t;
  43         buf += 4;
  44     } while (--longs);
  45 }
  46
  47 /* The four core functions - F1 is optimized somewhat */
  48
  49 /* #define F1(x, y, z) (x & y | ~x & z) */
  50 #define F1(x, y, z) (z ^ (x & (y ^ z)))
  51 #define F2(x, y, z) F1(z, x, y)
  52 #define F3(x, y, z) (x ^ y ^ z)
  53 #define F4(x, y, z) (y ^ (x | ~z))
  54
  55 /* This is the central step in the MD5 algorithm. */
  56 #define MD5STEP(f, w, x, y, z, data, s) \
  57         ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
  58
  59 /*
  60  * The core of the MD5 algorithm, this alters an existing MD5 hash to
  61  * reflect the addition of 16 longwords of new data.  MD5Update blocks
  62  * the data and converts bytes into longwords for this routine.
  63  */
  64 static void MD5Transform(uint32_t *buf, uint32_t *in)
  65 {
  66     register uint32_t a, b, c, d;
  67
  68     a = buf[0];
  69     b = buf[1];
  70     c = buf[2];
  71     d = buf[3];
  72
  73     MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
  74     MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
  75     MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
  76     MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
  77     MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
  78     MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
  79     MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
  80     MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
  81     MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
  82     MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
  83     MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
  84     MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
  85     MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
  86     MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
  87     MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
  88     MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
  89
  90     MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
  91     MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
  92     MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
  93     MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
  94     MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
  95     MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
  96     MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
  97     MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
  98     MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
  99     MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
 100     MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
 101     MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
 102     MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
 103     MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
 104     MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
 105     MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
 106
 107     MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
 108     MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
 109     MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
 110     MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
 111     MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
 112     MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
 113     MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
 114     MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
 115     MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
 116     MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
 117     MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
 118     MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
 119     MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
 120     MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
 121     MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
 122     MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
 123
 124     MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
 125     MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
 126     MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
 127     MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
 128     MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
 129     MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
 130     MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
 131     MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
 132     MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
 133     MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
 134     MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
 135     MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
 136     MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
 137     MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
 138     MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
 139     MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
 140
 141     buf[0] += a;
 142     buf[1] += b;
 143     buf[2] += c;
 144     buf[3] += d;
 145 }
 146
 147 /*
 148  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
 149  * initialization constants.
 150  */
 151 void MD5Init(struct MD5Context *ctx)
 152 {
 153     ctx->buf[0] = 0x67452301;
 154     ctx->buf[1] = 0xefcdab89;
 155     ctx->buf[2] = 0x98badcfe;
 156     ctx->buf[3] = 0x10325476;
 157
 158     ctx->bits[0] = 0;
 159     ctx->bits[1] = 0;
 160 }
 161
 162 /*
 163  * Update context to reflect the concatenation of another buffer full
 164  * of bytes.
 165  */
 166 void MD5Update(struct MD5Context *ctx, unsigned char *buf, unsigned len)
 167 {
 168     uint32_t t;
 169
 170     /* Update bitcount */
 171
 172     t = ctx->bits[0];
 173     if ((ctx->bits[0] = t + ((uint32_t) len << 3)) < t)
 174         ctx->bits[1]++;         /* Carry from low to high */
 175     ctx->bits[1] += len >> 29;
 176
 177     t = (t >> 3) & 0x3f;        /* Bytes already in shsInfo->data */
 178
 179     /* Handle any leading odd-sized chunks */
 180
 181     if (t) {
 182         unsigned char *p = (unsigned char *) ctx->in + t;
 183
 184         t = 64 - t;
 185         if (len < t) {
 186             memcpy(p, buf, len);
 187             return;
 188         }
 189         memcpy(p, buf, t);
 190         byteReverse(ctx->in, 16);
 191         MD5Transform(ctx->buf, (uint32_t *) ctx->in);
 192         buf += t;
 193         len -= t;
 194     }
 195     /* Process data in 64-byte chunks */
 196
 197     while (len >= 64) {
 198         memcpy(ctx->in, buf, 64);
 199         byteReverse(ctx->in, 16);
 200         MD5Transform(ctx->buf, (uint32_t *) ctx->in);
 201         buf += 64;
 202         len -= 64;
 203     }
 204
 205     /* Handle any remaining bytes of data. */
 206
 207     memcpy(ctx->in, buf, len);
 208 }
 209
 210 /*
 211  * Final wrapup - pad to 64-byte boundary with the bit pattern
 212  * 1 0* (64-bit count of bits processed, MSB-first)
 213  */
 214 void MD5Final(unsigned char *digest, struct MD5Context *ctx)
 215 {
 216     unsigned count;
 217     unsigned char *p;
 218
 219     /* Compute number of bytes mod 64 */
 220     count = (ctx->bits[0] >> 3) & 0x3F;
 221
 222     /* Set the first char of padding to 0x80.  This is safe since there is
 223        always at least one byte free */
 224     p = ctx->in + count;
 225     *p++ = 0x80;
 226
 227     /* Bytes of padding needed to make 64 bytes */
 228     count = 64 - 1 - count;
 229
 230     /* Pad out to 56 mod 64 */
 231     if (count < 8) {
 232         /* Two lots of padding:  Pad the first block to 64 bytes */
 233         memset(p, 0, count);
 234         byteReverse(ctx->in, 16);
 235         MD5Transform(ctx->buf, (uint32_t *) ctx->in);
 236
 237         /* Now fill the next block with 56 bytes */
 238         memset(ctx->in, 0, 56);
 239     } else {
 240         /* Pad block to 56 bytes */
 241         memset(p, 0, count - 8);
 242     }
 243     byteReverse(ctx->in, 14);
 244
 245     /* Append length in bits and transform */
 246     ((uint32_t *) ctx->in)[14] = ctx->bits[0];
 247     ((uint32_t *) ctx->in)[15] = ctx->bits[1];
 248
 249     MD5Transform(ctx->buf, (uint32_t *) ctx->in);
 250     byteReverse((unsigned char *) ctx->buf, 4);
 251     memcpy(digest, ctx->buf, 16);
 252     memset(ctx, 0, sizeof(ctx));        /* In case it's sensitive */
 253 }