openssl AES加密例子

openssl

OpenSSL 是一个安全套接字层密码库，囊括主要的密码算法、常用的密钥和证书封装管理功能及SSL协议，并提供丰富的应用程序供测试或其它目的使用。

首先，要安装 openssl:

centos命令:

sudo yum install openssl-devel

ubuntu命令：

sudo apt-get install libssl-dev

//========================================================================

//========================================================================
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <openssl/aes.h>
#include <openssl/evp.h>
#include <openssl/rsa.h>

void HexCode(unsigned char* data, int len)
{
    int i = 0;
    for(; i < len; i++)
        printf("%02x", (unsigned int)data[i]);
    printf("\n");
}

int main(void)
{
    const int len = 3;
    //AES 块到长度,是16个字节;
    printf("AES_BLOCK_SIZE = %d\n", AES_BLOCK_SIZE);

    char userkey[AES_BLOCK_SIZE] = {0};
    unsigned char *data = malloc(AES_BLOCK_SIZE*len);
    unsigned char *cipher = malloc(AES_BLOCK_SIZE*len);
    unsigned char *plain = malloc(AES_BLOCK_SIZE*len);

    int i;
    AES_KEY key = {0};

    memset((void*)userkey, 0, AES_BLOCK_SIZE);
    memset((void*)data, 0, AES_BLOCK_SIZE*len);
    memset((void*)cipher, 0, AES_BLOCK_SIZE*len);
    memset((void*)plain, 0, AES_BLOCK_SIZE*len);

    strcpy(userkey, "0123456789abcde");
    strcpy(data, "##@@!!!ABC123");

    printf("原始数据:\n");

    HexCode(data, AES_BLOCK_SIZE*len);

    //set key;
    printf("set aes key = %s\n", userkey);
    AES_set_encrypt_key(userkey, 128, &key);    //设置加密的秘钥;
    //执行加密;
    for(i = 0; i < len; i++)
    {
        AES_ecb_encrypt(data+i*AES_BLOCK_SIZE, cipher+i*AES_BLOCK_SIZE, &key, AES_ENCRYPT);
    }

    printf("加密数据:\n");
    HexCode(cipher, AES_BLOCK_SIZE*len);

    //set key to uncode
    AES_set_decrypt_key(userkey, 128, &key);    //设置解密的秘钥
    //执行解密;
    for(i = 0; i < len; i++)
    {
        AES_ecb_encrypt(cipher+i*AES_BLOCK_SIZE, plain+i*AES_BLOCK_SIZE, &key, AES_DECRYPT);
    }
    printf("揭密数据:\n");

    HexCode(plain, AES_BLOCK_SIZE*len);

    printf("uncode aes = %s\n", plain);

    free(data);
    free(cipher);
    free(plain);

    return 0;

}

编译：

#! /bin/sh

out=exe

rm $out

gcc test.c -o $out -lcrypto

运行：

[hill@Ubunut10 aes]$./make.sh 
[hill@Ubunut10 aes]$./exe 
AES_BLOCK_SIZE = 16
原始数据:
232340402121214142433132330000000000000000000000000000000000000000000000000000000000000000000000
set aes key = 0123456789abcde
加密数据:
1f84ced9ca24eafed2cf4709b2324578b7a085b9b36333a3a667929584c40c1bb7a085b9b36333a3a667929584c40c1b
揭密数据:
232340402121214142433132330000000000000000000000000000000000000000000000000000000000000000000000
uncode aes = ##@@!!!ABC123
[hill@Ubunut10 aes]$

//========================================================================

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