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| #include "md5.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#define READ_DATA_SIZE 1024
#define MD5_SIZE 16
#define MD5_STR_LEN (MD5_SIZE * 2)
// function declare
int Compute_string_md5(unsigned char *dest_str, unsigned int dest_len, char *md5_str);
int Compute_file_md5(const char *file_path, char *md5_str);
/************** main test **************/
int main(int argc, char *argv[])
{
int ret;
const char *file_path = "md5.c";
char md5_str[MD5_STR_LEN + 1];
const char *test_str = "gchinaran@gmail.com";
// test file md5
ret = Compute_file_md5(file_path, md5_str);
if (0 == ret)
{
printf("[file - %s] md5 value:\n", file_path);
printf("%s\n", md5_str);
}
// test string md5
Compute_string_md5((unsigned char *)test_str, strlen(test_str), md5_str);
printf("[string - %s] md5 value:\n", test_str);
printf("%s\n", md5_str);
return 0;
}
/**
* compute the value of a string
* @param dest_str
* @param dest_len
* @param md5_str
*/
int Compute_string_md5(unsigned char *dest_str, unsigned int dest_len, char *md5_str)
{
int i;
unsigned char md5_value[MD5_SIZE];
MD5_CTX md5;
// init md5
MD5Init(&md5);
MD5Update(&md5, dest_str, dest_len);
MD5Final(&md5, md5_value);
// convert md5 value to md5 string
for(i = 0; i < MD5_SIZE; i++)
{
snprintf(md5_str + i*2, 2+1, "%02x", md5_value[i]);
}
return 0;
}
/**
* compute the value of a file
* @param file_path
* @param md5_str
* @return 0: ok, -1: fail
*/
int Compute_file_md5(const char *file_path, char *md5_str)
{
int i;
int fd;
int ret;
unsigned char data[READ_DATA_SIZE];
unsigned char md5_value[MD5_SIZE];
MD5_CTX md5;
fd = open(file_path, O_RDONLY);
if (-1 == fd)
{
perror("open");
return -1;
}
// init md5
MD5Init(&md5);
while (1)
{
ret = read(fd, data, READ_DATA_SIZE);
if (-1 == ret)
{
perror("read");
close(fd);
return -1;
}
MD5Update(&md5, data, ret);
if (0 == ret || ret < READ_DATA_SIZE)
{
break;
}
}
close(fd);
MD5Final(&md5, md5_value);
// convert md5 value to md5 string
for(i = 0; i < MD5_SIZE; i++)
{
snprintf(md5_str + i*2, 2+1, "%02x", md5_value[i]);
}
return 0;
}
|
