网上找到的实现md5函数代码,包括一个头文件md5.h和一个源文件md5.c,用下面的测试代码test.c测试通过,各文件依次如下:
头文件md5.h
- #ifndef MD5_H
- #define MD5_H
-
- typedef struct
- {
- unsigned int count[2];
- unsigned int state[4];
- unsigned char buffer[64];
- }MD5_CTX;
-
-
- #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))
- #define ROTATE_LEFT(x,n) ((x << n) | (x >> (32-n)))
- #define FF(a,b,c,d,x,s,ac) \
- { \
- a += F(b,c,d) + x + ac; \
- a = ROTATE_LEFT(a,s); \
- a += b; \
- }
- #define GG(a,b,c,d,x,s,ac) \
- { \
- a += G(b,c,d) + x + ac; \
- a = ROTATE_LEFT(a,s); \
- a += b; \
- }
- #define HH(a,b,c,d,x,s,ac) \
- { \
- a += H(b,c,d) + x + ac; \
- a = ROTATE_LEFT(a,s); \
- a += b; \
- }
- #define II(a,b,c,d,x,s,ac) \
- { \
- a += I(b,c,d) + x + ac; \
- a = ROTATE_LEFT(a,s); \
- a += b; \
- }
- void MD5Init(MD5_CTX *context);
- void MD5Update(MD5_CTX *context,unsigned char *input,unsigned int inputlen);
- void MD5Final(MD5_CTX *context,unsigned char digest[16]);
- void MD5Transform(unsigned int state[4],unsigned char block[64]);
- void MD5Encode(unsigned char *output,unsigned int *input,unsigned int len);
- void MD5Decode(unsigned int *output,unsigned char *input,unsigned int len);
-
- #endif
源文件md5.c
- #include <memory.h>
- #include "md5.h"
-
- unsigned char PADDING[]={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};
-
- void MD5Init(MD5_CTX *context)
- {
- context->count[0] = 0;
- context->count[1] = 0;
- context->state[0] = 0x67452301;
- context->state[1] = 0xEFCDAB89;
- context->state[2] = 0x98BADCFE;
- context->state[3] = 0x10325476;
- }
- void MD5Update(MD5_CTX *context,unsigned char *input,unsigned int inputlen)
- {
- unsigned int i = 0,index = 0,partlen = 0;
- index = (context->count[0] >> 3) & 0x3F;
- partlen = 64 - index;
- context->count[0] += inputlen << 3;
- if(context->count[0] < (inputlen << 3))
- context->count[1]++;
- context->count[1] += inputlen >> 29;
-
- if(inputlen >= partlen)
- {
- memcpy(&context->buffer[index],input,partlen);
- MD5Transform(context->state,context->buffer);
- for(i = partlen;i+64 <= inputlen;i+=64)
- MD5Transform(context->state,&input[i]);
- index = 0;
- }
- else
- {
- i = 0;
- }
- memcpy(&context->buffer[index],&input[i],inputlen-i);
- }
- void MD5Final(MD5_CTX *context,unsigned char digest[16])
- {
- unsigned int index = 0,padlen = 0;
- unsigned char bits[8];
- index = (context->count[0] >> 3) & 0x3F;
- padlen = (index < 56)?(56-index):(120-index);
- MD5Encode(bits,context->count,8);
- MD5Update(context,PADDING,padlen);
- MD5Update(context,bits,8);
- MD5Encode(digest,context->state,16);
- }
- void MD5Encode(unsigned char *output,unsigned int *input,unsigned int len)
- {
- unsigned int i = 0,j = 0;
- while(j < len)
- {
- output[j] = input[i] & 0xFF;
- output[j+1] = (input[i] >> 8) & 0xFF;
- output[j+2] = (input[i] >> 16) & 0xFF;
- output[j+3] = (input[i] >> 24) & 0xFF;
- i++;
- j+=4;
- }
- }
- void MD5Decode(unsigned int *output,unsigned char *input,unsigned int len)
- {
- unsigned int i = 0,j = 0;
- while(j < len)
- {
- output[i] = (input[j]) |
- (input[j+1] << 8) |
- (input[j+2] << 16) |
- (input[j+3] << 24);
- i++;
- j+=4;
- }
- }
- void MD5Transform(unsigned int state[4],unsigned char block[64])
- {
- unsigned int a = state[0];
- unsigned int b = state[1];
- unsigned int c = state[2];
- unsigned int d = state[3];
- unsigned int x[64];
- MD5Decode(x,block,64);
- FF(a, b, c, d, x[ 0], 7, 0xd76aa478);
- FF(d, a, b, c, x[ 1], 12, 0xe8c7b756);
- FF(c, d, a, b, x[ 2], 17, 0x242070db);
- FF(b, c, d, a, x[ 3], 22, 0xc1bdceee);
- FF(a, b, c, d, x[ 4], 7, 0xf57c0faf);
- FF(d, a, b, c, x[ 5], 12, 0x4787c62a);
- FF(c, d, a, b, x[ 6], 17, 0xa8304613);
- FF(b, c, d, a, x[ 7], 22, 0xfd469501);
- FF(a, b, c, d, x[ 8], 7, 0x698098d8);
- FF(d, a, b, c, x[ 9], 12, 0x8b44f7af);
- FF(c, d, a, b, x[10], 17, 0xffff5bb1);
- FF(b, c, d, a, x[11], 22, 0x895cd7be);
- FF(a, b, c, d, x[12], 7, 0x6b901122);
- FF(d, a, b, c, x[13], 12, 0xfd987193);
- FF(c, d, a, b, x[14], 17, 0xa679438e);
- FF(b, c, d, a, x[15], 22, 0x49b40821);
-
-
- GG(a, b, c, d, x[ 1], 5, 0xf61e2562);
- GG(d, a, b, c, x[ 6], 9, 0xc040b340);
- GG(c, d, a, b, x[11], 14, 0x265e5a51);
- GG(b, c, d, a, x[ 0], 20, 0xe9b6c7aa);
- GG(a, b, c, d, x[ 5], 5, 0xd62f105d);
- GG(d, a, b, c, x[10], 9, 0x2441453);
- GG(c, d, a, b, x[15], 14, 0xd8a1e681);
- GG(b, c, d, a, x[ 4], 20, 0xe7d3fbc8);
- GG(a, b, c, d, x[ 9], 5, 0x21e1cde6);
- GG(d, a, b, c, x[14], 9, 0xc33707d6);
- GG(c, d, a, b, x[ 3], 14, 0xf4d50d87);
- GG(b, c, d, a, x[ 8], 20, 0x455a14ed);
- GG(a, b, c, d, x[13], 5, 0xa9e3e905);
- GG(d, a, b, c, x[ 2], 9, 0xfcefa3f8);
- GG(c, d, a, b, x[ 7], 14, 0x676f02d9);
- GG(b, c, d, a, x[12], 20, 0x8d2a4c8a);
-
-
- HH(a, b, c, d, x[ 5], 4, 0xfffa3942);
- HH(d, a, b, c, x[ 8], 11, 0x8771f681);
- HH(c, d, a, b, x[11], 16, 0x6d9d6122);
- HH(b, c, d, a, x[14], 23, 0xfde5380c);
- HH(a, b, c, d, x[ 1], 4, 0xa4beea44);
- HH(d, a, b, c, x[ 4], 11, 0x4bdecfa9);
- HH(c, d, a, b, x[ 7], 16, 0xf6bb4b60);
- HH(b, c, d, a, x[10], 23, 0xbebfbc70);
- HH(a, b, c, d, x[13], 4, 0x289b7ec6);
- HH(d, a, b, c, x[ 0], 11, 0xeaa127fa);
- HH(c, d, a, b, x[ 3], 16, 0xd4ef3085);
- HH(b, c, d, a, x[ 6], 23, 0x4881d05);
- HH(a, b, c, d, x[ 9], 4, 0xd9d4d039);
- HH(d, a, b, c, x[12], 11, 0xe6db99e5);
- HH(c, d, a, b, x[15], 16, 0x1fa27cf8);
- HH(b, c, d, a, x[ 2], 23, 0xc4ac5665);
-
-
- II(a, b, c, d, x[ 0], 6, 0xf4292244);
- II(d, a, b, c, x[ 7], 10, 0x432aff97);
- II(c, d, a, b, x[14], 15, 0xab9423a7);
- II(b, c, d, a, x[ 5], 21, 0xfc93a039);
- II(a, b, c, d, x[12], 6, 0x655b59c3);
- II(d, a, b, c, x[ 3], 10, 0x8f0ccc92);
- II(c, d, a, b, x[10], 15, 0xffeff47d);
- II(b, c, d, a, x[ 1], 21, 0x85845dd1);
- II(a, b, c, d, x[ 8], 6, 0x6fa87e4f);
- II(d, a, b, c, x[15], 10, 0xfe2ce6e0);
- II(c, d, a, b, x[ 6], 15, 0xa3014314);
- II(b, c, d, a, x[13], 21, 0x4e0811a1);
- II(a, b, c, d, x[ 4], 6, 0xf7537e82);
- II(d, a, b, c, x[11], 10, 0xbd3af235);
- II(c, d, a, b, x[ 2], 15, 0x2ad7d2bb);
- II(b, c, d, a, x[ 9], 21, 0xeb86d391);
- state[0] += a;
- state[1] += b;
- state[2] += c;
- state[3] += d;
- }
测试代码test.c
- #include <stdio.h>
- #include <stdlib.h>
- #include "md5.h"
-
- int main(int argc, char *argv[])
- {
- int i;
- unsigned char encrypt[] ="admin";
- unsigned char decrypt[16];
- MD5_CTX md5;
- MD5Init(&md5);
- MD5Update(&md5,encrypt,strlen((char *)encrypt));
- MD5Final(&md5,decrypt);
- printf("加密前:%s\n加密后:",encrypt);
- for(i=0;i<16;i++)
- {
- printf("%02x",decrypt[i]);
- }
-
- getchar();
-
- return 0;
- }
C语言实现md5函数代码,布布扣,bubuko.com
C语言实现md5函数代码
原文:http://www.cnblogs.com/xunbu7/p/3890412.html