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bird 1.6.3

    1: /*
    2:  *	BIRD Library -- MD5 Hash Function and HMAC-MD5 Function
    3:  *
    4:  *	(c) 2015 CZ.NIC z.s.p.o.
    5:  *
    6:  *	The code was written by Colin Plumb in 1993, no copyright is claimed.
    7:  *
    8:  *	Adapted for BIRD by Martin Mares <mj@ucw.cz>
    9:  *
   10:  *	Can be freely distributed and used under the terms of the GNU GPL.
   11:  */
   12: 
   13: #include "lib/md5.h"
   14: 
   15: #ifdef CPU_LITTLE_ENDIAN
   16: #define byteReverse(buf, len)	/* Nothing */
   17: #else
   18: void byteReverse(byte *buf, uint longs);
   19: 
   20: /*
   21:  * Note: this code is harmless on little-endian machines.
   22:  */
   23: void byteReverse(byte *buf, uint longs)
   24: {
   25:   u32 t;
   26:   do {
   27:     t = (u32) ((uint) buf[3] << 8 | buf[2]) << 16 |
   28: 	((uint) buf[1] << 8 | buf[0]);
   29:     *(u32 *) buf = t;
   30:     buf += 4;
   31:   } while (--longs);
   32: }
   33: #endif
   34: 
   35: static void md5_transform(u32 buf[4], u32 const in[16]);
   36: 
   37: /*
   38:  * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
   39:  * initialization constants.
   40:  */
   41: void
   42: md5_init(struct hash_context *CTX)
   43: {
   44:   struct md5_context *ctx = (void *) CTX;
   45: 
   46:   ctx->buf[0] = 0x67452301;
   47:   ctx->buf[1] = 0xefcdab89;
   48:   ctx->buf[2] = 0x98badcfe;
   49:   ctx->buf[3] = 0x10325476;
   50: 
   51:   ctx->bits[0] = 0;
   52:   ctx->bits[1] = 0;
   53: }
   54: 
   55: /*
   56:  * Update context to reflect the concatenation of another buffer full
   57:  * of bytes.
   58:  */
   59: void
   60: md5_update(struct hash_context *CTX, const byte *buf, uint len)
   61: {
   62:   struct md5_context *ctx = (void *) CTX;
   63:   u32 t;
   64: 
   65:   /* Update bitcount */
   66: 
   67:   t = ctx->bits[0];
   68:   if ((ctx->bits[0] = t + ((u32) len << 3)) < t)
   69:     ctx->bits[1]++;		/* Carry from low to high */
   70:   ctx->bits[1] += len >> 29;
   71: 
   72:   t = (t >> 3) & 0x3f;	/* Bytes already in shsInfo->data */
   73: 
   74:   /* Handle any leading odd-sized chunks */
   75:   if (t)
   76:   {
   77:     byte *p = (byte *) ctx->in + t;
   78: 
   79:     t = 64 - t;
   80:     if (len < t)
   81:     {
   82:       memcpy(p, buf, len);
   83:       return;
   84:     }
   85:     memcpy(p, buf, t);
   86:     byteReverse(ctx->in, 16);
   87:     md5_transform(ctx->buf, (u32 *) ctx->in);
   88:     buf += t;
   89:     len -= t;
   90:   }
   91: 
   92:   /* Process data in 64-byte chunks */
   93:   while (len >= 64)
   94:   {
   95:     memcpy(ctx->in, buf, 64);
   96:     byteReverse(ctx->in, 16);
   97:     md5_transform(ctx->buf, (u32 *) ctx->in);
   98:     buf += 64;
   99:     len -= 64;
  100:   }
  101: 
  102:   /* Handle any remaining bytes of data. */
  103:   memcpy(ctx->in, buf, len);
  104: }
  105: 
  106: /*
  107:  * Final wrapup - pad to 64-byte boundary with the bit pattern
  108:  * 1 0* (64-bit count of bits processed, MSB-first)
  109:  */
  110: byte *
  111: md5_final(struct hash_context *CTX)
  112: {
  113:   struct md5_context *ctx = (void *) CTX;
  114:   uint count;
  115:   byte *p;
  116: 
  117:   /* Compute number of bytes mod 64 */
  118:   count = (ctx->bits[0] >> 3) & 0x3F;
  119: 
  120:   /* Set the first char of padding to 0x80.  This is safe since there is
  121:        always at least one byte free */
  122:   p = ctx->in + count;
  123:   *p++ = 0x80;
  124: 
  125:   /* Bytes of padding needed to make 64 bytes */
  126:   count = 64 - 1 - count;
  127: 
  128:   /* Pad out to 56 mod 64 */
  129:   if (count < 8)
  130:   {
  131:     /* Two lots of padding:  Pad the first block to 64 bytes */
  132:     memset(p, 0, count);
  133:     byteReverse(ctx->in, 16);
  134:     md5_transform(ctx->buf, (u32 *) ctx->in);
  135: 
  136:     /* Now fill the next block with 56 bytes */
  137:     memset(ctx->in, 0, 56);
  138:   }
  139:   else
  140:   {
  141:     /* Pad block to 56 bytes */
  142:     memset(p, 0, count - 8);
  143:   }
  144:   byteReverse(ctx->in, 14);
  145: 
  146:   /* Append length in bits and transform */
  147:   ((u32 *) ctx->in)[14] = ctx->bits[0];
  148:   ((u32 *) ctx->in)[15] = ctx->bits[1];
  149: 
  150:   md5_transform(ctx->buf, (u32 *) ctx->in);
  151:   byteReverse((byte *) ctx->buf, 4);
  152: 
  153:   return (byte*) ctx->buf;
  154: }
  155: 
  156: /* The four core functions - F1 is optimized somewhat */
  157: 
  158: /* #define F1(x, y, z) (x & y | ~x & z) */
  159: #define F1(x, y, z) (z ^ (x & (y ^ z)))
  160: #define F2(x, y, z) F1(z, x, y)
  161: #define F3(x, y, z) (x ^ y ^ z)
  162: #define F4(x, y, z) (y ^ (x | ~z))
  163: 
  164: /* This is the central step in the MD5 algorithm. */
  165: #define MD5STEP(f, w, x, y, z, data, s) \
  166:     ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
  167: 
  168: /*
  169:  * The core of the MD5 algorithm, this alters an existing MD5 hash to
  170:  * reflect the addition of 16 longwords of new data.  MD5Update blocks
  171:  * the data and converts bytes into longwords for this routine.
  172:  */
  173: void
  174: md5_transform(u32 buf[4], u32 const in[16])
  175: {
  176:   register u32 a, b, c, d;
  177: 
  178:   a = buf[0];
  179:   b = buf[1];
  180:   c = buf[2];
  181:   d = buf[3];
  182: 
  183:   MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
  184:   MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
  185:   MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
  186:   MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
  187:   MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
  188:   MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
  189:   MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
  190:   MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
  191:   MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
  192:   MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
  193:   MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
  194:   MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
  195:   MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
  196:   MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
  197:   MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
  198:   MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
  199: 
  200:   MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
  201:   MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
  202:   MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
  203:   MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
  204:   MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
  205:   MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
  206:   MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
  207:   MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
  208:   MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
  209:   MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
  210:   MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
  211:   MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
  212:   MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
  213:   MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
  214:   MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
  215:   MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
  216: 
  217:   MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
  218:   MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
  219:   MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
  220:   MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
  221:   MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
  222:   MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
  223:   MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
  224:   MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
  225:   MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
  226:   MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
  227:   MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
  228:   MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
  229:   MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
  230:   MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
  231:   MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
  232:   MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
  233: 
  234:   MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
  235:   MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
  236:   MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
  237:   MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
  238:   MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
  239:   MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
  240:   MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
  241:   MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
  242:   MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
  243:   MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
  244:   MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
  245:   MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
  246:   MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
  247:   MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
  248:   MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
  249:   MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
  250: 
  251:   buf[0] += a;
  252:   buf[1] += b;
  253:   buf[2] += c;
  254:   buf[3] += d;
  255: }