text: /* Parts Copyright 2004 David Hammerton <crazney@crazney.net>
   * Parts found in the public domain with no copyright claim.
   *
   * see rfc1321
   *
   * Permission is hereby granted, free of charge, to any person
   * obtaining a copy of this software and associated documentation
   * files (the "Software"), to deal in the Software without
   * restriction, including without limitation the rights to use,
   * copy, modify, merge, publish, distribute, sublicense, and/or
   * sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be
   * included in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
   * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
   * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
   * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   * OTHER DEALINGS IN THE SOFTWARE.
   *
   */
  
  #include <string.h>
  #include "md5.h"
  
  /*
  * This code implements the MD5 message-digest algorithm.
  * The algorithm is due to Ron Rivest.  This code was
  * written by Colin Plumb in 1993, no copyright is claimed.
  * This code is in the public domain; do with it what you wish.
  *
  * Equivalent code is available from RSA Data Security, Inc.
  * This code has been tested against that, and is equivalent,
  * except that you don't need to include two pages of legalese
  * with every copy.
  *
  * To compute the message digest of a chunk of bytes, declare an MD5Context
  * structure, pass it to OpenDaap_MD5Init, call OpenDaap_MD5Update as needed
  * on buffers full of bytes, and then call OpenDaap_MD5Final, which will fill
  * a supplied 16-byte array with the digest.
  */
  static void MD5Transform(u_int32_t buf[4], u_int32_t const in[16], int apple_ver);
  /* for some reason we still have to reverse bytes on bigendian machines
   * I don't really know why... but otherwise it fails..
   * Any MD5 gurus out there know why???
   */
  #if 0 //ndef WORDS_BIGENDIAN /* was: HIGHFIRST */
  #define byteReverse(buf, len)     /* Nothing */
  #else
  static void byteReverse(unsigned char *buf, unsigned longs);
  
  #ifndef ASM_MD5
  /*
  * Note: this code is harmless on little-endian machines.
  */
  static void byteReverse(unsigned char *buf, unsigned longs)
  {
       u_int32_t t;
       do {
            t = (u_int32_t) ((unsigned) buf[3] << 8 | buf[2]) << 16 |
                 ((unsigned) buf[1] << 8 | buf[0]);
            *(u_int32_t *) buf = t;
            buf += 4;
       } while (--longs);
  }
  #endif
  #endif
  
  
  void OpenDaap_MD5Init(MD5_CTX *ctx, int apple_ver)
  {
      memset(ctx, 0, sizeof(MD5_CTX));
      ctx->buf[0] = 0x67452301;
      ctx->buf[1] = 0xefcdab89;
      ctx->buf[2] = 0x98badcfe;
      ctx->buf[3] = 0x10325476;
  
      ctx->bits[0] = 0;
      ctx->bits[1] = 0;
  
      ctx->apple_ver = apple_ver;
  }
  
  void OpenDaap_MD5Update(MD5_CTX *ctx, unsigned char const *buf, unsigned int len)
  {
      u_int32_t t;
  
      /* Update bitcount */
  
      t = ctx->bits[0];
      if ((ctx->bits[0] = t + ((u_int32_t) len << 3)) < t)
          ctx->bits[1]++;          /* Carry from low to high */
      ctx->bits[1] += len >> 29;
  
      t = (t >> 3) & 0x3f;     /* Bytes already in shsInfo->data */
  
      /* Handle any leading odd-sized chunks */
  
      if (t) {
          unsigned char *p = (unsigned char *) ctx->in + t;
  
          t = 64 - t;
          if (len < t) {
              memcpy(p, buf, len);
              return;
          }
          memcpy(p, buf, t);
          byteReverse(ctx->in, 16);
          MD5Transform(ctx->buf, (u_int32_t *) ctx->in, ctx->apple_ver);
          buf += t;
          len -= t;
      }
      /* Process data in 64-byte chunks */
  
      while (len >= 64) {
          memcpy(ctx->in, buf, 64);
          byteReverse(ctx->in, 16);
          MD5Transform(ctx->buf, (u_int32_t *) ctx->in, ctx->apple_ver);
          buf += 64;
          len -= 64;
      }
  
      /* Handle any remaining bytes of data. */
  
      memcpy(ctx->in, buf, len);
  
  }
  
  void OpenDaap_MD5Final(MD5_CTX *ctx, unsigned char digest[16])
  {
      unsigned count;
      unsigned char *p;
  
      /* Compute number of bytes mod 64 */
      count = (ctx->bits[0] >> 3) & 0x3F;
  
      /* Set the first char of padding to 0x80.  This is safe since there is
      always at least one byte free */
      p = ctx->in + count;
      *p++ = 0x80;
  
      /* Bytes of padding needed to make 64 bytes */
      count = 64 - 1 - count;
  
      /* Pad out to 56 mod 64 */
      if (count < 8) {
          /* Two lots of padding:  Pad the first block to 64 bytes */
          memset(p, 0, count);
          byteReverse(ctx->in, 16);
          MD5Transform(ctx->buf, (u_int32_t *) ctx->in, ctx->apple_ver);
  
          /* Now fill the next block with 56 bytes */
          memset(ctx->in, 0, 56);
      } else {
          /* Pad block to 56 bytes */
          memset(p, 0, count - 8);
      }
      byteReverse(ctx->in, 14);
  
      /* Append length in bits and transform */
      ((u_int32_t *) ctx->in)[14] = ctx->bits[0];
      ((u_int32_t *) ctx->in)[15] = ctx->bits[1];
  
      MD5Transform(ctx->buf, (u_int32_t *) ctx->in, ctx->apple_ver);
      byteReverse((unsigned char *) ctx->buf, 4);
      memcpy(digest, ctx->buf, 16);
      memset(ctx, 0, sizeof(ctx));     /* In case it's sensitive */
  }
  
  #ifndef ASM_MD5
  
  /* The four core functions - F1 is optimized somewhat */
  
  /* #define F1(x, y, z) (x & y | ~x & z) */
  #define F1(x, y, z) (z ^ (x & (y ^ z)))
  #define F2(x, y, z) F1(z, x, y)
  #define F3(x, y, z) (x ^ y ^ z)
  #define F4(x, y, z) (y ^ (x | ~z))
  
  /* This is the central step in the MD5 algorithm. */
  #define MD5STEP(f, w, x, y, z, data, s) \
  ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
  
  /*
  * The core of the MD5 algorithm, this alters an existing MD5 hash to reflect
  * the addition of 16 longwords of new data.  OpenDaap_MD5Update blocks the
  * data and converts bytes into longwords for this routine.
  */
  static void MD5Transform(u_int32_t buf[4], u_int32_t const in[16], int apple_ver)
  {
      u_int32_t a, b, c, d;
  
      a = buf[0];
      b = buf[1];
      c = buf[2];
      d = buf[3];
  
      MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
      MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
      MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
      MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
      MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
      MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
      MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
      MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
      MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
      MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
      MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
      MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
      MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
      MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
      MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
      MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
  
      MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
      MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
      MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
      MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
      MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
      MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
      MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
      MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
      MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
      MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
      MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
  
      if (apple_ver == 1)
      {
          MD5STEP(F2, b, c, d, a, in[8] + 0x445a14ed, 20);
      }
      else
      {
          MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
      }
      MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
      MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
      MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
      MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
  
      MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
      MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
      MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
      MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
      MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
      MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
      MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
      MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
      MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
      MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
      MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
      MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
      MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
      MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
      MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
      MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
  
      MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
      MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
      MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
      MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
      MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
      MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
      MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
      MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
      MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
      MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
      MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
      MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
      MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
      MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
      MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
      MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
  
      buf[0] += a;
      buf[1] += b;
      buf[2] += c;
      buf[3] += d;
  }
  
  #endif
  
  
  
  