from: http://blog.sina.com.cn/s/blog_693de6100101kcu6.html
注：以下是md5加密算法c语言版(16/32位)
---------------------------------------------------
网上找到的md5函数的实现，包括三个文件，依次如下：
头文件 TL_MD5.h
[cpp]
#ifndef MD5_H
#define MD5_H typedef struct
{
unsigned int count[];
unsigned int state[];
unsigned char buffer[];
}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[]);
void MD5Transform(unsigned int state[],unsigned char block[]);
void MD5Encode(unsigned char *output,unsigned int *input,unsigned int len);
void MD5Decode(unsigned int *output,unsigned char *input,unsigned int len); #endif
C/C++语言实现文件 TL_MD5.c 或者 TL_MD5.cpp
[cpp]
#include <string.h>
#include "md5.h" unsigned char PADDING[]={0x80,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,}; void MD5Init(MD5_CTX *context)
{
context->count[] = ;
context->count[] = ;
context->state[] = 0x67452301;
context->state[] = 0xEFCDAB89;
context->state[] = 0x98BADCFE;
context->state[] = 0x10325476;
}
void MD5Update(MD5_CTX *context,unsigned char *input,unsigned int inputlen)
{
unsigned int i = ,index = ,partlen = ;
index = (context->count[] >> ) & 0x3F;
partlen = - index;
context->count[] += inputlen << ;
if(context->count[] < (inputlen << ))
context->count[]++;
context->count[] += inputlen >> ; if(inputlen >= partlen)
{
memcpy(&context->buffer[index],input,partlen);
MD5Transform(context->state,context->buffer);
for(i = partlen;i+ <= inputlen;i+=)
MD5Transform(context->state,&input[i]);
index = ;
}
else
{
i = ;
}
memcpy(&context->buffer[index],&input[i],inputlen-i);
}
void MD5Final(MD5_CTX *context,unsigned char digest[])
{
unsigned int index = ,padlen = ;
unsigned char bits[];
index = (context->count[] >> ) & 0x3F;
padlen = (index < )?(-index):(-index);
MD5Encode(bits,context->count,);
MD5Update(context,PADDING,padlen);
MD5Update(context,bits,);
MD5Encode(digest,context->state,);
}
void MD5Encode(unsigned char *output,unsigned int *input,unsigned int len)
{
unsigned int i = ,j = ;
while(j < len)
{
output[j] = input[i] & 0xFF;
output[j+] = (input[i] >> ) & 0xFF;
output[j+] = (input[i] >> ) & 0xFF;
output[j+] = (input[i] >> ) & 0xFF;
i++;
j+=;
}
}
void MD5Decode(unsigned int *output,unsigned char *input,unsigned int len)
{
unsigned int i = ,j = ;
while(j < len)
{
output[i] = (input[j]) |
(input[j+] << ) |
(input[j+] << ) |
(input[j+] << );
i++;
j+=;
}
}
void MD5Transform(unsigned int state[],unsigned char block[])
{
unsigned int a = state[];
unsigned int b = state[];
unsigned int c = state[];
unsigned int d = state[];
unsigned int x[];
MD5Decode(x,block,);
FF(a, b, c, d, x[ ], , 0xd76aa478);
FF(d, a, b, c, x[ ], , 0xe8c7b756);
FF(c, d, a, b, x[ ], , 0x242070db);
FF(b, c, d, a, x[ ], , 0xc1bdceee);
FF(a, b, c, d, x[ ], , 0xf57c0faf);
FF(d, a, b, c, x[ ], , 0x4787c62a);
FF(c, d, a, b, x[ ], , 0xa8304613);
FF(b, c, d, a, x[ ], , 0xfd469501);
FF(a, b, c, d, x[ ], , 0x698098d8);
FF(d, a, b, c, x[ ], , 0x8b44f7af);
FF(c, d, a, b, x[], , 0xffff5bb1);
FF(b, c, d, a, x[], , 0x895cd7be);
FF(a, b, c, d, x[], , 0x6b901122);
FF(d, a, b, c, x[], , 0xfd987193);
FF(c, d, a, b, x[], , 0xa679438e);
FF(b, c, d, a, x[], , 0x49b40821); GG(a, b, c, d, x[ ], , 0xf61e2562);
GG(d, a, b, c, x[ ], , 0xc040b340);
GG(c, d, a, b, x[], , 0x265e5a51);
GG(b, c, d, a, x[ ], , 0xe9b6c7aa);
GG(a, b, c, d, x[ ], , 0xd62f105d);
GG(d, a, b, c, x[], , 0x2441453);
GG(c, d, a, b, x[], , 0xd8a1e681);
GG(b, c, d, a, x[ ], , 0xe7d3fbc8);
GG(a, b, c, d, x[ ], , 0x21e1cde6);
GG(d, a, b, c, x[], , 0xc33707d6);
GG(c, d, a, b, x[ ], , 0xf4d50d87);
GG(b, c, d, a, x[ ], , 0x455a14ed);
GG(a, b, c, d, x[], , 0xa9e3e905);
GG(d, a, b, c, x[ ], , 0xfcefa3f8);
GG(c, d, a, b, x[ ], , 0x676f02d9);
GG(b, c, d, a, x[], , 0x8d2a4c8a); HH(a, b, c, d, x[ ], , 0xfffa3942);
HH(d, a, b, c, x[ ], , 0x8771f681);
HH(c, d, a, b, x[], , 0x6d9d6122);
HH(b, c, d, a, x[], , 0xfde5380c);
HH(a, b, c, d, x[ ], , 0xa4beea44);
HH(d, a, b, c, x[ ], , 0x4bdecfa9);
HH(c, d, a, b, x[ ], , 0xf6bb4b60);
HH(b, c, d, a, x[], , 0xbebfbc70);
HH(a, b, c, d, x[], , 0x289b7ec6);
HH(d, a, b, c, x[ ], , 0xeaa127fa);
HH(c, d, a, b, x[ ], , 0xd4ef3085);
HH(b, c, d, a, x[ ], , 0x4881d05);
HH(a, b, c, d, x[ ], , 0xd9d4d039);
HH(d, a, b, c, x[], , 0xe6db99e5);
HH(c, d, a, b, x[], , 0x1fa27cf8);
HH(b, c, d, a, x[ ], , 0xc4ac5665); II(a, b, c, d, x[ ], , 0xf4292244);
II(d, a, b, c, x[ ], , 0x432aff97);
II(c, d, a, b, x[], , 0xab9423a7);
II(b, c, d, a, x[ ], , 0xfc93a039);
II(a, b, c, d, x[], , 0x655b59c3);
II(d, a, b, c, x[ ], , 0x8f0ccc92);
II(c, d, a, b, x[], , 0xffeff47d);
II(b, c, d, a, x[ ], , 0x85845dd1);
II(a, b, c, d, x[ ], , 0x6fa87e4f);
II(d, a, b, c, x[], , 0xfe2ce6e0);
II(c, d, a, b, x[ ], , 0xa3014314);
II(b, c, d, a, x[], , 0x4e0811a1);
II(a, b, c, d, x[ ], , 0xf7537e82);
II(d, a, b, c, x[], , 0xbd3af235);
II(c, d, a, b, x[ ], , 0x2ad7d2bb);
II(b, c, d, a, x[ ], , 0xeb86d391);
state[] += a;
state[] += b;
state[] += c;
state[] += d;
}
md5函数测试代码文件
[cpp]
#include
#include
#include
#include "md5.h" int main(int argc, char *argv[])
{
MD5_CTX md5;
MD5Init(&md5);
int i;
unsigned char encrypt[] ="admin";//21232f297a57a5a743894a0e4a801fc3
unsigned char decrypt[];
MD5Update(&md5,encrypt,strlen((char *)encrypt));
MD5Final(&md5,decrypt);
printf("加密前:%s\n加密后16位:",encrypt);
for(i=;i<;i++)
{
printf("02x",decrypt[i]); //02x前需要加上 %
} printf("\n加密前:%s\n加密后32位:",encrypt);
for(i=;i<;i++)
{
printf("02x",decrypt[i]); //02x前需要加上 %
} getchar(); return ;
}
7a57a5a743894a0e admin(16位MD5小写加密)
972130B75066C825 ADMIN(16位MD5大写加密)
21232f297a57a5a743894a0e4a801fc3 admin(32位MD5小写加密)
73ACD9A5972130B75066C82595A1FAE3 ADMIN(32位MD5大写加密)
49ba59abbe56e057 123456(16位MD5小写加密)
e10adc3949ba59abbe56e057f20f883e 123456(32位MD5小写加密)
469e80d32c0559f8 admin888(16位MD5小写加密)
2299413865C28A35 ADMIN888(16位MD5大写加密)
7fef6171469e80d32c0559f88b377245 admin888(32位MD5小写加密)
A1F63A962299413865C28A3593D359B0 ADMIN888(32位MD5大写加密)
md5知识扫盲
MD5：是一个散列算法，但非加密算法（因为没有密钥）
MD5是一种单向散列函数，单向散列函数的作用是将任何长度的一段数据散列成固定长度。常用于生成消息认证码等等，可以与非对称算法一起用于数字签名。
标准见http://www.ietf.org/rfc/rfc1321.txt
在线MD5计算 http://www.cmd5.com/