使用openssl中的EVP通用加密算法接口的之－－hash散列运算测试例子

/*********************************************************************
 * Author  : Samson
 * Date    : 01/22/2014
 * Test platform:
 *               3.6.10-4.fc18.i686.PAE
 *               GNU bash, version 4.2.39
 * *******************************************************************/

#include <stdio.h>

#include <string.h>
#include <errno.h>
#include <resolv.h>
#include <stdlib.h>
#include <unistd.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/x509.h>

#define EVP_MAX_MD_SIZE 64
#define MD5_RESULT_LEN 16
#define DATA_LEN 8

char msg[]="\x61\x62\x63\x64\x65\x66\x67\x68";
int main()
{
        unsigned char md_value[EVP_MAX_MD_SIZE];
        unsigned int md_len,i;
        EVP_MD_CTX mdctx;
        OpenSSL_add_all_algorithms();
        EVP_MD_CTX_init(&mdctx);

        EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL);
        EVP_DigestUpdate(&mdctx, msg, DATA_LEN);
        EVP_DigestFinal_ex(&mdctx, md_value, &md_len);
        EVP_MD_CTX_cleanup(&mdctx);

        printf("MD5:");
        for(i = 0; i < md_len; i++)
        {
                printf("%02x ", md_value[i]);
        }
        printf("\r\n");
    return 0;

}

编译：

[ufo@localhost fuck]$ gcc testhash.c -Wall -g -lssl -lcrypto -o hash

运行结果：
[ufo@localhost fuck]$ ./hash
MD5:e8 dc 40 81 b1 34 34 b4 51 89 a7 20 b7 7b 68 18