rob@76: /* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
rob@76:  */
rob@76: 
rob@76: /* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
rob@76: rights reserved.
rob@76: 
rob@76: License to copy and use this software is granted provided that it
rob@76: is identified as the "RSA Data Security, Inc. MD5 Message-Digest
rob@76: Algorithm" in all material mentioning or referencing this software
rob@76: or this function.
rob@76: 
rob@76: License is also granted to make and use derivative works provided
rob@76: that such works are identified as "derived from the RSA Data
rob@76: Security, Inc. MD5 Message-Digest Algorithm" in all material
rob@76: mentioning or referencing the derived work.
rob@76: 
rob@76: RSA Data Security, Inc. makes no representations concerning either
rob@76: the merchantability of this software or the suitability of this
rob@76: software for any particular purpose. It is provided "as is"
rob@76: without express or implied warranty of any kind.
rob@76: 
rob@76: These notices must be retained in any copies of any part of this
rob@76: documentation and/or software.
rob@76:  */
rob@76: 
rob@76: #include "md5.h"
rob@76: 
rob@76: /* Constants for MD5Transform routine.
rob@76:  */
rob@76: 
rob@76: #define S11 7
rob@76: #define S12 12
rob@76: #define S13 17
rob@76: #define S14 22
rob@76: #define S21 5
rob@76: #define S22 9
rob@76: #define S23 14
rob@76: #define S24 20
rob@76: #define S31 4
rob@76: #define S32 11
rob@76: #define S33 16
rob@76: #define S34 23
rob@76: #define S41 6
rob@76: #define S42 10
rob@76: #define S43 15
rob@76: #define S44 21
rob@76: 
rob@76: static void MD5Transform(UINT4 [4], unsigned char [64]);
rob@76: static void Encode(unsigned char *, UINT4 *, unsigned int);
rob@76: static void Decode(UINT4 *, unsigned char *, unsigned int);
rob@76: static void MD5_memcpy(POINTER, POINTER, unsigned int);
rob@76: static void MD5_memset(POINTER, int, unsigned int);
rob@76: 
rob@76: static unsigned char PADDING[64] = {
rob@76:   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
rob@76:   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
rob@76:   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
rob@76: };
rob@76: 
rob@76: /* F, G, H and I are basic MD5 functions.
rob@76:  */
rob@76: #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
rob@76: #define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
rob@76: #define H(x, y, z) ((x) ^ (y) ^ (z))
rob@76: #define I(x, y, z) ((y) ^ ((x) | (~z)))
rob@76: 
rob@76: /* ROTATE_LEFT rotates x left n bits.
rob@76:  */
rob@76: #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
rob@76: 
rob@76: /* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
rob@76: Rotation is separate from addition to prevent recomputation.
rob@76:  */
rob@76: #define FF(a, b, c, d, x, s, ac) { \
rob@76:  (a) += F ((b), (c), (d)) + (x) + (UINT4)(ac); \
rob@76:  (a) = ROTATE_LEFT ((a), (s)); \
rob@76:  (a) += (b); \
rob@76:   }
rob@76: #define GG(a, b, c, d, x, s, ac) { \
rob@76:  (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
rob@76:  (a) = ROTATE_LEFT ((a), (s)); \
rob@76:  (a) += (b); \
rob@76:   }
rob@76: #define HH(a, b, c, d, x, s, ac) { \
rob@76:  (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
rob@76:  (a) = ROTATE_LEFT ((a), (s)); \
rob@76:  (a) += (b); \
rob@76:   }
rob@76: #define II(a, b, c, d, x, s, ac) { \
rob@76:  (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
rob@76:  (a) = ROTATE_LEFT ((a), (s)); \
rob@76:  (a) += (b); \
rob@76:   }
rob@76: 
rob@76: /* MD5 initialization. Begins an MD5 operation, writing a new context.
rob@76:  */
rob@76: void MD5Init( MD5_CTX *context )
rob@76: {
rob@76:   context->count[0] = context->count[1] = 0;
rob@76:   /* Load magic initialization constants.
rob@76: */
rob@76:   context->state[0] = 0x67452301;
rob@76:   context->state[1] = 0xefcdab89;
rob@76:   context->state[2] = 0x98badcfe;
rob@76:   context->state[3] = 0x10325476;
rob@76: }
rob@76: 
rob@76: /* MD5 block update operation. Continues an MD5 message-digest
rob@76:   operation, processing another message block, and updating the
rob@76:   context.
rob@76:  */
rob@76: void MD5Update( MD5_CTX *context, unsigned char *input, unsigned int inputLen )
rob@76: {
rob@76:   unsigned int i, index, partLen;
rob@76: 
rob@76:   /* Compute number of bytes mod 64 */
rob@76:   index = (unsigned int)((context->count[0] >> 3) & 0x3F);
rob@76: 
rob@76:   /* Update number of bits */
rob@76:   if ((context->count[0] += ((UINT4)inputLen << 3))
rob@76: 
rob@76:    < ((UINT4)inputLen << 3))
rob@76:  context->count[1]++;
rob@76:   context->count[1] += ((UINT4)inputLen >> 29);
rob@76: 
rob@76:   partLen = 64 - index;
rob@76: 
rob@76:   /* Transform as many times as possible.
rob@76: */
rob@76:   if (inputLen >= partLen) {
rob@76:  MD5_memcpy
rob@76:    ((POINTER)&context->buffer[index], (POINTER)input, partLen);
rob@76:  MD5Transform (context->state, context->buffer);
rob@76: 
rob@76:  for (i = partLen; i + 63 < inputLen; i += 64)
rob@76:    MD5Transform (context->state, &input[i]);
rob@76: 
rob@76:  index = 0;
rob@76:   }
rob@76:   else
rob@76:  i = 0;
rob@76: 
rob@76:   /* Buffer remaining input */
rob@76:   MD5_memcpy
rob@76:  ((POINTER)&context->buffer[index], (POINTER)&input[i],
rob@76:   inputLen-i);
rob@76: }
rob@76: 
rob@76: /* MD5 finalization. Ends an MD5 message-digest operation, writing the
rob@76:   the message digest and zeroizing the context.
rob@76:  */
rob@76: void MD5Final( unsigned char digest[16], MD5_CTX *context )
rob@76: {
rob@76:   unsigned char bits[8];
rob@76:   unsigned int index, padLen;
rob@76: 
rob@76:   /* Save number of bits */
rob@76:   Encode (bits, context->count, 8);
rob@76: 
rob@76:   /* Pad out to 56 mod 64.
rob@76: */
rob@76:   index = (unsigned int)((context->count[0] >> 3) & 0x3f);
rob@76:   padLen = (index < 56) ? (56 - index) : (120 - index);
rob@76:   MD5Update (context, PADDING, padLen);
rob@76: 
rob@76:   /* Append length (before padding) */
rob@76:   MD5Update (context, bits, 8);
rob@76: 
rob@76:   /* Store state in digest */
rob@76:   Encode (digest, context->state, 16);
rob@76: 
rob@76:   /* Zeroize sensitive information.
rob@76: */
rob@76:   MD5_memset ((POINTER)context, 0, sizeof (*context));
rob@76: }
rob@76: 
rob@76: /* MD5 basic transformation. Transforms state based on block.
rob@76:  */
rob@76: static void MD5Transform( UINT4 state[4], unsigned char block[64] )
rob@76: {
rob@76:   UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
rob@76: 
rob@76:   Decode (x, block, 64);
rob@76: 
rob@76:   /* Round 1 */
rob@76:   FF (a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
rob@76:   FF (d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
rob@76:   FF (c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
rob@76:   FF (b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
rob@76:   FF (a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
rob@76:   FF (d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
rob@76:   FF (c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
rob@76:   FF (b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
rob@76:   FF (a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
rob@76:   FF (d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
rob@76:   FF (c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
rob@76:   FF (b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
rob@76:   FF (a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
rob@76:   FF (d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
rob@76:   FF (c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
rob@76:   FF (b, c, d, a, x[15], S14, 0x49b40821); /* 16 */
rob@76: 
rob@76:  /* Round 2 */
rob@76:   GG (a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
rob@76:   GG (d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
rob@76:   GG (c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
rob@76:   GG (b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
rob@76:   GG (a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
rob@76:   GG (d, a, b, c, x[10], S22,  0x2441453); /* 22 */
rob@76:   GG (c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
rob@76:   GG (b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
rob@76:   GG (a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
rob@76:   GG (d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
rob@76:   GG (c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
rob@76: 
rob@76:   GG (b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
rob@76:   GG (a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
rob@76:   GG (d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
rob@76:   GG (c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
rob@76:   GG (b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */
rob@76: 
rob@76:   /* Round 3 */
rob@76:   HH (a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
rob@76:   HH (d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
rob@76:   HH (c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
rob@76:   HH (b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
rob@76:   HH (a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
rob@76:   HH (d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
rob@76:   HH (c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
rob@76:   HH (b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
rob@76:   HH (a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
rob@76:   HH (d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
rob@76:   HH (c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
rob@76:   HH (b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
rob@76:   HH (a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
rob@76:   HH (d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
rob@76:   HH (c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
rob@76:   HH (b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */
rob@76: 
rob@76:   /* Round 4 */
rob@76:   II (a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
rob@76:   II (d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
rob@76:   II (c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
rob@76:   II (b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
rob@76:   II (a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
rob@76:   II (d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
rob@76:   II (c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
rob@76:   II (b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
rob@76:   II (a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
rob@76:   II (d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
rob@76:   II (c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
rob@76:   II (b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
rob@76:   II (a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
rob@76:   II (d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
rob@76:   II (c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
rob@76:   II (b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
rob@76: 
rob@76:   state[0] += a;
rob@76:   state[1] += b;
rob@76:   state[2] += c;
rob@76:   state[3] += d;
rob@76: 
rob@76:   /* Zeroize sensitive information.
rob@76: 
rob@76: */
rob@76:   MD5_memset ((POINTER)x, 0, sizeof (x));
rob@76: }
rob@76: 
rob@76: /* Encodes input (UINT4) into output (unsigned char). Assumes len is
rob@76:   a multiple of 4.
rob@76:  */
rob@76: static void Encode( unsigned char *output, UINT4 *input, unsigned int len )
rob@76: {
rob@76:   unsigned int i, j;
rob@76: 
rob@76:   for (i = 0, j = 0; j < len; i++, j += 4) {
rob@76:  output[j] = (unsigned char)(input[i] & 0xff);
rob@76:  output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
rob@76:  output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
rob@76:  output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
rob@76:   }
rob@76: }
rob@76: 
rob@76: /* Decodes input (unsigned char) into output (UINT4). Assumes len is
rob@76:   a multiple of 4.
rob@76:  */
rob@76: static void Decode( UINT4 *output, unsigned char *input, unsigned int len )
rob@76: {
rob@76:   unsigned int i, j;
rob@76: 
rob@76:   for (i = 0, j = 0; j < len; i++, j += 4)
rob@76:  output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) |
rob@76:    (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
rob@76: }
rob@76: 
rob@76: /* Note: Replace "for loop" with standard memcpy if possible.
rob@76:  */
rob@76: 
rob@76: static void MD5_memcpy( POINTER output, POINTER input, unsigned int len )
rob@76: {
rob@76:   unsigned int i;
rob@76: 
rob@76:   for (i = 0; i < len; i++)
rob@76: 
rob@76:  output[i] = input[i];
rob@76: }
rob@76: 
rob@76: /* Note: Replace "for loop" with standard memset if possible.
rob@76:  */
rob@76: static void MD5_memset( POINTER output, int value, unsigned int len )
rob@76: {
rob@76:   unsigned int i;
rob@76: 
rob@76:   for (i = 0; i < len; i++)
rob@76:  ((char *)output)[i] = (char)value;
rob@76: }
rob@76: