使用tomcrypt库来进行加密

上一篇文章是使用RSA加密的.

因为对于随机数算法的不信任.所以就自己抄了个随机数算法.以后改起来也能改.说不定还能改成真随机数算法.并且使用tomcrypt里面自带的高级RSA功能加密时我把官方文档里的代码放进去用的时候发现运行有问题.我懒得改他的代码.就自己写了一个.这次是使用官方的方法来进行对称算法的加密解密.

/*
 * twofish.c
 *
 * Created on: 2012-7-31
 * Author: zzl
 */
#include <tomcrypt.h>
/*
 * 支持多种加密函数和加密方式。具体情况请参考tomcrypt_cipher.h
 */
int main(void)
{
unsigned char pt[8]={'c','h','i','n','a'}, ct[8]={0,0,0,0,0,0,0,0}, key[8]={'c','h','i','n','a'};
symmetric_key skey;
int err;
/* ... key is loaded appropriately in key ... */
/* ... load a block of plaintext in pt ... */
/* schedule the key */
if ((err = blowfish_setup(key, /* the key we will use */
8, /* key is 8 bytes (64-bits) long */
0, /* 0 == use default # of rounds */
&skey) /* where to put the scheduled key */
) != CRYPT_OK) {
printf("Setup error: %s\n", error_to_string(err));
return -1;
}

printf("Setup key: %s\n", key);
//printf("Setup skey: %s\n", skey);
/* encrypt the block */
blowfish_ecb_encrypt(pt, /* encrypt this 8-byte array */
ct, /* store encrypted data here */
&skey); /* our previously scheduled key */
int i;
//如果不清空key则也会打印key的值
for(i=0;i<8;i++)
    key[i]=0;
printf("blowfish_ecb_encrypt ct: %s\n", ct);
/* now ct holds the encrypted version of pt */
/* decrypt the block */
blowfish_ecb_decrypt(ct, /* decrypt this 8-byte array */
pt, /* store decrypted data here */
&skey); /* our previously scheduled key */
/* now we have decrypted ct to the original plaintext in pt */
/* Terminate the cipher context */
printf("blowfish_ecb_encrypt pt: %s\n", pt);
blowfish_done(&skey);
return 0;
}

对称算法包括

blowfish_ecb_encrypt

rc5_ecb_encrypt

rc6_ecb_encrypt

rc2_ecb_encrypt

saferp_ecb_encrypt

safer_ecb_encrypt 包括safer_k64 safer_sk64 safer_k128 safer_sk128

rijndael_ecb_encrypt 也就是aes_ecb_encrypt

xtea_ecb_encrypt

twofish_ecb_encrypt

des_ecb_encrypt

des3_ecb_encrypt

cast5_ecb_encrypt

noekeon_ecb_encrypt

skipjack_ecb_encrypt

khazad_ecb_encrypt

anubis_ecb_encrypt

kseed_ecb_encrypt

kasumi_ecb_encrypt

multi2_ecb_encrypt

等方法.

后面还有ecb cfb cbc等加密方式.

使用加密方法的时候把demo里面的XXX_setup XXX_ecb_encrypt XXX_ecb_decrypt XXX_done换成上面的内容就行了.

到目前为止使用tommath库和tomcrypt库可以完成对称和非对称的加密解密算法了.