md5.c

MD5加解密算法

/* This program is C)opyright by LinXiaoDong */
#include <windows.h>
#include "global.h"
#include "md5.h"

#include <stdio.h>
#include <malloc.h>
#include <string.h>
#include <stdlib.h>

/* 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

#define SIZE 64
#define TRUE 1

void MD5Init(MD5_CTX *);
void MD5Update(MD5_CTX *, unsigned char *, unsigned int);
void MD5Final (unsigned char [16], MD5_CTX *);
void MD5Update(MD5_CTX *, unsigned char *, unsigned int);
void MD5Final (unsigned char [16], MD5_CTX *);
static void MD5Transform(UINT4 [4], unsigned char [64]);
static void Encode(unsigned char *, UINT4 *, unsigned int);
static void Decode(UINT4 *, unsigned char *, unsigned int);
static void MD5_memcpy(POINTER, POINTER, unsigned int);
static void MD5_memset(POINTER, int, unsigned int);
static void MD5_memchange(POINTER,UINT4 *);
int WINAPI DLLEntryPoint (HINSTANCE hDLL, DWORD dwReason, LPVOID Reserved);

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); \
  }

// MD5 initialization. Begins an MD5 operation, writing a new context.
 
void 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.
 */

//MD5_CTX *context;         // context
//unsigned char *input;     // input block 
//unsigned int inputLen;    // length of input block 


void MD5Update(MD5_CTX *context,unsigned char *input,unsigned int inputLen)
{
  unsigned int i,index,partLen;

  // Compute number of bytes mod 64 
  index = (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 - index;

  // Transform as many times as possible.

  if (inputLen >= partLen)
    {
     MD5_memcpy((POINTER)&context->buffer[index], (POINTER)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((POINTER)&context->buffer[index], (POINTER)&input[i],inputLen-i);
}

void MD5Final(unsigned char digest[16],MD5_CTX *context)
{
  unsigned char bits[8];
  unsigned int index, padLen;

  // Save number of bits 
  Encode (bits, 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);
  // Store state in digest 
  Encode (digest, context->state, 16);

  // Zeroize sensitive information.
  MD5_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.
  MD5_memset((POINTER)x,0,sizeof(x));
}

// Encodes input (UINT4) into output (unsigned char). Assumes len is
//  a multiple of 4.

//unsigned char *output;
//UINT4 *input;
//unsigned int len;

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)
{