md5.cpp

网络传输方面的范例程序,其中有MD5加密和解密的子程序,可以参考

// MD5.cpp: implementation of the CMD5 class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "MD5.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif

#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

//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 nbits.
#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);}

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CMD5::CMD5()
{
	int i;

	PADDING [0] = 0x80;
	for (i=1;i<64;i++)
		PADDING [i] = 0;
}

CMD5::~CMD5()
{

}

void CMD5::MD5Init (MD5_CTX *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.
 */
void CMD5::MD5Update (MD5_CTX *context, unsigned char *input, ULONG inputLen)
{
  register ULONG i;
  unsigned int index, partLen;

  /* Compute number of bytes mod 64 */
  index = (unsigned int)((context->count[0] >> 3) & 0x3F);

  /* Update number of bits */
  if ((context->count[0] += (inputLen << 3)) < (inputLen << 3))
	context->count[1]++;
  context->count[1] += (inputLen >> 29);

  partLen = 64 - index;

  /* Transform as many times as possible. lbl has changed inputLen>=partLen
and use i replace it*/
  if (inputLen>=partLen) {
	MD5_memcpy((PUCHAR)&context->buffer[index], (PUCHAR)input, partLen);
	MD5Transform (context->state, context->buffer);

	for (i = partLen; i + 63 < inputLen; i += 64)
	    MD5Transform (context->state, &input[i]);

	index = 0;
  }
  else
	i = 0;

  /* Buffer remaining input */
  MD5_memcpy((PUCHAR)(&context->buffer[index]), (PUCHAR)(&input[i]), inputLen-i);
}

/* MD5 finalization. Ends an MD5 message-digest operation, writing the
  the message digest and zeroizing the context.
 */
void CMD5::MD5Final (unsigned char digest[16], MD5_CTX *context)
{
  unsigned char bits[8];
  unsigned int index, padLen;

  /* Save number of bits */
  MD5_memcpy((PUCHAR)bits, (PUCHAR)context->count, 8);

  /* Pad out to 56 mod 64.
*/
  index = (unsigned int)((context->count[0] >> 3) & 0x3f);
  padLen = (index < 56) ? (56 - index) : (120 - index);
  MD5Update (context, PADDING, padLen);

  /* Append length (before padding) */
  MD5Update (context, bits, 8);

  if (digest != NULL)			/* Bill Simpson's padding */
  {
	  /* store state in digest */
	  MD5_memcpy((PUCHAR)digest, (PUCHAR)context->state, 16);

	  /* Zeroize sensitive information.
	   */
	  MD5_memset((PUCHAR)(context),0,sizeof(MD5_CTX));
  }
}

/* MD5 basic transformation. Transforms state based on block.
 */
void CMD5::MD5Transform (ULONG state[4], unsigned char block[64])
{
  ULONG a = state[0], b = state[1], c = state[2], d = state[3], x[16];

  MD5_memcpy ((PUCHAR)x, (PUCHAR)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;
  MD5_memset((PUCHAR)x,0,sizeof(x));
}
void CMD5::MD5_memcpy(POINTER output, POINTER input, unsigned int len)
{

	//register unsigned int i;
	//POINTER pout=output;
	//POINTER pin=input;
	//for (i = 0; i < len; i++)
	//	*pout++ = *pin++;
	memcpy(output,input,len);

}

void CMD5::MD5_memset(POINTER output, unsigned char value, unsigned int len)
{
	register unsigned int i;
	POINTER pout=output;
	for (i = 0; i < len; i++)
		*pout++ = value;
}

void CMD5::Digest_data(unsigned char *input,int inputlen,unsigned char digest[16])
{
	MD5_CTX context;
    MD5Init(&context);
    MD5Update(&context,input,inputlen);
    MD5Final(digest,&context);
	return ;
}

void CMD5::Digest_file(CString fn,unsigned char digest[16])
{
	FILE *file;
	MD5_CTX context;
	int len;
	unsigned char *buffer;
	
	if ((file =fopen (fn, "rb")) == NULL)
	{
		MessageBox (NULL,"无法打开文件或文件不存在","错误",MB_OK);
		return ;
	}
	buffer=new unsigned char[50*1024];
	MD5Init (&context);
	while (len = fread (buffer, 1, 50*1024, file))
	{
		MD5Update (&context, buffer, len);
		MD5Final (digest, &context);
	}
	fclose (file);
	return ;

}