text: /*
    This Library has been modified from its original form by 
    Brian Aker (brian@tangent.org)
  
    See below for original Copyright.
  */
  /* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
   */
  
  /* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
  rights reserved.
  
  License to copy and use this software is granted provided that it
  is identified as the "RSA Data Security, Inc. MD5 Message-Digest
  Algorithm" in all material mentioning or referencing this software
  or this function.
  
  License is also granted to make and use derivative works provided
  that such works are identified as "derived from the RSA Data
  Security, Inc. MD5 Message-Digest Algorithm" in all material
  mentioning or referencing the derived work.
  
  RSA Data Security, Inc. makes no representations concerning either
  the merchantability of this software or the suitability of this
  software for any particular purpose. It is provided "as is"
  without express or implied warranty of any kind.
  
  These notices must be retained in any copies of any part of this
  documentation and/or software.
  */
  
  #include "common.h"
  
  #include <string.h>
  #include <sys/types.h>
  
  /* POINTER defines a generic pointer type */
  typedef unsigned char *POINTER;
  
  
  /* UINT4 defines a four byte word */
  typedef unsigned int UINT4;
  
  
  /* MD5 context. */
  typedef struct {
    UINT4 state[4];                                   /* state (ABCD) */
    UINT4 count[2];        /* number of bits, modulo 2^64 (lsb first) */
    unsigned char buffer[64];                         /* input buffer */
  } MD5_CTX;
  
  static void MD5Init (MD5_CTX *context);      /* context */
  static void MD5Update ( MD5_CTX *context,                                        /* context */
                          const unsigned char *input,                              /* input block */
                          unsigned int inputLen);                     /* length of input block */
  static void MD5Final ( unsigned char digest[16],                         /* message digest */
                         MD5_CTX *context);                              /* context */
  
  /* Constants for MD5Transform routine. */
  
  #define S11 7
  #define S12 12
  #define S13 17
  #define S14 22
  #define S21 5
  #define S22 9
  #define S23 14
  #define S24 20
  #define S31 4
  #define S32 11
  #define S33 16
  #define S34 23
  #define S41 6
  #define S42 10
  #define S43 15
  #define S44 21
  
  
  static void MD5Transform (UINT4 state[4],
                            unsigned char block[64]);
  static void Encode (unsigned char *output,
                      UINT4 *input,
                      unsigned int len);
  static void Decode(UINT4 *output, unsigned char *input, unsigned int len);
  
  static unsigned char PADDING[64] = {
    0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  };
  
  /* F, G, H and I are basic MD5 functions.
   */
  #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
  #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
  #define H(x, y, z) ((x) ^ (y) ^ (z))
  #define I(x, y, z) ((y) ^ ((x) | (~z)))
  
  /* ROTATE_LEFT rotates x left n bits.
   */
  #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
  
  /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
  Rotation is separate from addition to prevent recomputation.
   */
  #define FF(a, b, c, d, x, s, ac) { \
   (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
    }
  #define GG(a, b, c, d, x, s, ac) { \
   (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
    }
  #define HH(a, b, c, d, x, s, ac) { \
   (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
    }
  #define II(a, b, c, d, x, s, ac) { \
   (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
    }
  
  
  /* 
    Just a simple method for getting the signature
    result must be == 16
  */
  void md5_signature(const unsigned char *key, unsigned int length, unsigned char *result)
  {
      MD5_CTX my_md5;
  
      MD5Init(&my_md5);
      (void)MD5Update(&my_md5, key, length);
      MD5Final(result, &my_md5);
  }
  
  /* MD5 initialization. Begins an MD5 operation, writing a new context.
   */
  static void MD5Init (MD5_CTX *context)      /* context */
  {
    context->count[0] = context->count[1] = 0;
    /* Load magic initialization constants.
  */
    context->state[0] = 0x67452301;
    context->state[1] = 0xefcdab89;
    context->state[2] = 0x98badcfe;
    context->state[3] = 0x10325476;
  }
  
  /* MD5 block update operation. Continues an MD5 message-digest
    operation, processing another message block, and updating the
    context.
   */
  
  static void MD5Update (
                         MD5_CTX *context,                                        /* context */
                         const unsigned char *input,                              /* input block */
                         unsigned int inputLen)                     /* length of input block */
  {
    unsigned int i, idx, partLen;
  
    /* Compute number of bytes mod 64 */
    idx = (unsigned int)((context->count[0] >> 3) & 0x3F);
  
  
    /* Update number of bits */
    if ((context->count[0] += ((UINT4)inputLen << 3))
        < ((UINT4)inputLen << 3))
      context->count[1]++;
    context->count[1] += ((UINT4)inputLen >> 29);
  
    partLen = 64 - idx;
  
    /* Transform as many times as possible.
  */
    if (inputLen >= partLen) {
   memcpy((POINTER)&context->buffer[idx], (POINTER)input, partLen);
   MD5Transform(context->state, context->buffer);
  
   for (i = partLen; i + 63 < inputLen; i += 64)
     MD5Transform (context->state, (unsigned char *)&input[i]);
  
   idx = 0;
    }
    else
   i = 0;
  
    /* Buffer remaining input */
    memcpy((POINTER)&context->buffer[idx], (POINTER)&input[i],
  	     inputLen-i);
  }
  
  /* MD5 finalization. Ends an MD5 message-digest operation, writing the
    the message digest and zeroizing the context.
   */
  
  static void MD5Final (
                        unsigned char digest[16],                         /* message digest */
                        MD5_CTX *context)                              /* context */
  {
    unsigned char bits[8];
    unsigned int idx, padLen;
  
    /* Save number of bits */
    Encode (bits, context->count, 8);
  
    /* Pad out to 56 mod 64.
  */
    idx = (unsigned int)((context->count[0] >> 3) & 0x3f);
    padLen = (idx < 56) ? (56 - idx) : (120 - idx);
    MD5Update (context, PADDING, padLen);
  
    /* Append length (before padding) */
    MD5Update (context, bits, 8);
  
    /* Store state in digest */
    Encode (digest, context->state, 16);
  
    /* Zeroize sensitive information.
  */
    memset((POINTER)context, 0, sizeof (*context));
  }
  
  /* MD5 basic transformation. Transforms state based on block.
   */
  static void MD5Transform (
                            UINT4 state[4],
                            unsigned char block[64])
  {
    UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
  
    Decode (x, block, 64);
  
    /* Round 1 */
    FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
    FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
    FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
    FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
    FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
    FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
    FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
    FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
    FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
    FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
    FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
    FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
    FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
    FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
    FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
    FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
  
   /* Round 2 */
    GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
    GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
    GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
    GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
    GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
    GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
    GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
    GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
    GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
    GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
    GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
    GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
    GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
    GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
    GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
    GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
  
    /* Round 3 */
    HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
    HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
    HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
    HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
    HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
    HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
    HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
    HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
    HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
    HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
    HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
    HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
    HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
    HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
    HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
    HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
  
    /* Round 4 */
    II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
    II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
    II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
    II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
    II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
    II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
    II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
    II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
    II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
    II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
    II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
    II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
    II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
    II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
    II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
    II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
  
  
    state[0] += a;
    state[1] += b;
    state[2] += c;
    state[3] += d;
  
    /* Zeroize sensitive information.
  */
    memset((POINTER)x, 0, sizeof (x));
  }
  
  /* Encodes input (UINT4) into output (unsigned char). Assumes len is
    a multiple of 4.
   */
  static void Encode (
  unsigned char *output,
  UINT4 *input,
  unsigned int len)
  {
    unsigned int i, j;
  
    for (i = 0, j = 0; j < len; i++, j += 4) {
   output[j] = (unsigned char)(input[i] & 0xff);
   output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
   output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
   output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
    }
  }
  
  
  /* Decodes input (unsigned char) into output (UINT4). Assumes len is
    a multiple of 4.
   */
  static void Decode (
  UINT4 *output,
  unsigned char *input,
  unsigned int len)
  {
    unsigned int i, j;
  
    for (i = 0, j = 0; j < len; i++, j += 4)
   output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
     (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
  }
  
  uint32_t hashkit_md5(const char *key, size_t key_length, void *context __attribute__((unused)))
  {
    unsigned char results[16];
  
    md5_signature((unsigned char*)key, (unsigned int)key_length, results);
  
    return ((uint32_t) (results[3] & 0xFF) << 24)
      | ((uint32_t) (results[2] & 0xFF) << 16)
      | ((uint32_t) (results[1] & 0xFF) << 8)
      | (results[0] & 0xFF);
  }
  