// cryptoDemo.cpp : Defines the entry point for the console application.

// Windows: cl cryptoDemo.cpp

// Linux: gcc -o cryptoDemo cryptoDemo.cpp -lcrypto

#include <memory.h>

#include <stdio.h>

#include <string.h>

#include <stdlib.h>

#include "openssl/aes.h"

#pragma comment(lib,"libeay32.lib")

void testAes(char inString[], int inLen, char passwd[], int pwdLen)

{

int i,j, len, nLoop, nRes;

char enString[1024];

char deString[1024];

unsigned char buf[16];

unsigned char buf2[16];

unsigned char aes_keybuf[32];

AES_KEY aeskey;

// 准备32字节(256位)的AES密码字节

memset(aes_keybuf,0x90,32);

if(pwdLen<32){ len=pwdLen; } else { len=32;}

for(i=0;i<len;i++) aes_keybuf[i]=passwd[i];

// 输入字节串分组成16字节的块

nLoop=inLen/16; nRes = inLen%16;

// 加密输入的字节串

AES_set_encrypt_key(aes_keybuf,256,&aeskey);

for(i=0;i<nLoop;i++){

memset(buf,0,16);

for(j=0;j<16;j++) buf[j]=inString[i*16+j];

AES_encrypt(buf,buf2,&aeskey);

for(j=0;j<16;j++) enString[i*16+j]=buf2[j];

}

if(nRes>0){

memset(buf,0,16);

for(j=0;j<nRes;j++) buf[j]=inString[i*16+j];

AES_encrypt(buf,buf2,&aeskey);

for(j=0;j<16;j++) enString[i*16+j]=buf2[j];

//puts("encrypt");

}

enString[i*16+j]=0;

// 密文串的解密

AES_set_decrypt_key(aes_keybuf,256,&aeskey);

for(i=0;i<nLoop;i++){

memset(buf,0,16);

for(j=0;j<16;j++) buf[j]=enString[i*16+j];

AES_decrypt(buf,buf2,&aeskey);

for(j=0;j<16;j++) deString[i*16+j]=buf2[j];

}

if(nRes>0){

memset(buf,0,16);

for(j=0;j<16;j++) buf[j]=enString[i*16+j];

AES_decrypt(buf,buf2,&aeskey);

for(j=0;j<16;j++) deString[i*16+j]=buf2[j];

//puts("decrypt");

}

deString[i*16+nRes]=0;

//比较解密后的串是否与输入的原始串相同

if(memcmp(inString,deString,strlen(inString))==0)

{ printf("test success\r\n");} else { printf("test fail\r\n");}

printf("The original string is:\n %s ", inString);

printf("The encrypted string is:\n %s ", enString);

printf("The decrypted string is:\n %s ", deString);

}

int main(int argc, char* argv[])

{

char inString[] = "This is a sample. I am a programer.\n";

char passwd[] = "0123456789ABCDEFGHIJK";

testAes(inString, strlen(inString), passwd, strlen(passwd));

return 0;

}