C语言求文件MD5的函数用法

Posted 2023-05-08

byte[] data = new byte[DATA_SIZE];
MD5 md5 = new MD5CryptoServiceProvider();
byte[] result = md5.ComputeHash(data);
这个函数怎么用？。。

#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); /* 1 */
FF(d, a, b, c, x[ 1], 12, 0xe8c7b756); /* 2 */
FF(c, d, a, b, x[ 2], 17, 0x242070db); /* 3 */
FF(b, c, d, a, x[ 3], 22, 0xc1bdceee); /* 4 */
FF(a, b, c, d, x[ 4], 7, 0xf57c0faf); /* 5 */
FF(d, a, b, c, x[ 5], 12, 0x4787c62a); /* 6 */
FF(c, d, a, b, x[ 6], 17, 0xa8304613); /* 7 */
FF(b, c, d, a, x[ 7], 22, 0xfd469501); /* 8 */
FF(a, b, c, d, x[ 8], 7, 0x698098d8); /* 9 */
FF(d, a, b, c, x[ 9], 12, 0x8b44f7af); /* 10 */
FF(c, d, a, b, x[10], 17, 0xffff5bb1); /* 11 */
FF(b, c, d, a, x[11], 22, 0x895cd7be); /* 12 */
FF(a, b, c, d, x[12], 7, 0x6b901122); /* 13 */
FF(d, a, b, c, x[13], 12, 0xfd987193); /* 14 */
FF(c, d, a, b, x[14], 17, 0xa679438e); /* 15 */
FF(b, c, d, a, x[15], 22, 0x49b40821); /* 16 */ 参考技术A C语言没有内置的MD5函数，可以在以下页面找到C语言实现程序和MD5的算法介绍：

http://tools.ietf.org/html/rfc1321本回答被提问者采纳

c语言编程题 利用指针编写函数用选择法对整数数组排序(降序)。 求大神帮忙啊！！！谢谢

#include<stdio.h>

void Sort(int *a,int n) 
int *p,*q,*v,t;
for(p = a;p < a + n - 1;++p) 
v = p;
for(q = p + 1; q < a + n; ++q)
if(*v > *q) v = q;
if(*p != *v) 
t = *p;
*p = *v;
*v = t;





void Show(int *a,int n) 
int i;
for(i = 0; i < n; ++i)
printf("%d ",*(a + i));
printf("\\n");


int main() 
int a[] = 23,12,54,89,66,59,57,48,91,20,31;
int n = sizeof(a)/sizeof(a[0]);
printf("排序前:\\n");
Show(a,n);
printf("排序后:\\n");
Sort(a,n);
Show(a,n);
return 0;

参考技术A #include <iostream>
using namespace std;
int sort(int *a, int num)

int temp;
for(int i = 0; i < (num-1); i++)

if(a[i]>a[i+1])

temp = a[i];
a[i] = a[i+1];
a[i+1] = temp;


return 0;

int main()

int num;
printf("请输入数组中整数个数：\n")；
scanf("%d",&num);
int a[num];
sort(a,num);
return 0;

本回答被提问者采纳