加密解密,3des加密解密类程序代码

3DES(或称为Triple DES)是三重数据加密算法(TDEA,Triple Data Encryption
Algorithm)块密码的通称。它相当于是对每个数据块应用三次DES加密算法。由于计算机运算能力的增强,原版DES密码的密钥长度变得容易被暴力破解;3DES即是设计用来提供一种相对简单的方法,即通过增加DES的密钥长度来避免类似的攻击,而不是设计一种全新的块密码算法。

1、DES加密实例

//DES加密

public static function encrypt($input, $key) {

    $size = mcrypt_get_block_size(‘des’, ‘cbc’);//使用CBC加密模式

    $input = Banktest::pkcs5_pad($input, $size);

    $td = mcrypt_module_open(‘des’, ”, ‘cbc’, ”);

    $iv = ‘LTtlK61d’;//偏移量(根据实际情况赋值)

    mcrypt_generic_init($td, $key, $iv);

    $data = mcrypt_generic($td, $input);

    mcrypt_generic_deinit($td);

    mcrypt_module_close($td);

    $data = base64_encode($data);

    return $data;

}

//填充模式

private static function pkcs5_pad ($text, $blocksize){

    $pad = $blocksize – (strlen($text) % $blocksize);

    return $text . str_repeat(chr($pad), $pad);

}

class Security{
public static $_key = ‘1234567890123456’;
public static $_skey = ‘1234567890exampl’;

public static function encrypt($input) {
$key = hex2bin(self::$_skey);
$input = hex2bin($input);
$size = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128,
MCRYPT_MODE_ECB);
//$input = Security::pkcs5_pad($input, $size);
$td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, ”,
MCRYPT_MODE_ECB, ”);
$iv = mcrypt_create_iv(mcrypt_enc_get_iv_size($td),
MCRYPT_RAND);
mcrypt_generic_init($td, $key, $iv);
$data = mcrypt_generic($td, $input);
mcrypt_generic_deinit($td);
mcrypt_module_close($td);
$data = base64_encode($data);
return $data;
}
private static function pkcs5_pad($text, $blocksize) {
$pad = $blocksize – (strlen($text) % $blocksize);
return $text . str_repeat(‘0d’, $pad);
}
public static function decrypt($sStr) {
//echo “until_data:–“;
$sStr = hex2bin($sStr);
//var_dump($sStr);
$sKey = hex2bin(self::$_skey);
$decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $sKey,
base64_decode($sStr), MCRYPT_MODE_ECB);
$decrypted_hex = bin2hex($decrypted);
$complement = substr($decrypted_hex, strlen($decrypted_hex) – 2,
2);
return str_replace($complement, ”, $decrypted_hex);
}
}

 代码如下

2、AES加密实例

public function encrypt($input, $key) {

    $size = mcrypt_get_block_size(MCRYPT_RIJNDAEL_128,
MCRYPT_MODE_ECB);

    $input =$this->pkcs5_pad($input, $size);

    $td = mcrypt_module_open(MCRYPT_RIJNDAEL_128, ”,
MCRYPT_MODE_ECB, ”);

    $iv = mcrypt_create_iv (mcrypt_enc_get_iv_size($td),
MCRYPT_RAND);

    mcrypt_generic_init($td, $key, $iv);

    $data = mcrypt_generic($td, $input);

    mcrypt_generic_deinit($td);

    mcrypt_module_close($td);

    $data = base64_encode($data);

    return $data;

}

public function pkcs5_pad ($text, $blocksize){

    $pad = $blocksize – (strlen($text) % $blocksize);

    return $text . str_repeat(chr($pad), $pad);

}

public function decrypt($dStr, $dKey) {

    $decrypted=
mcrypt_decrypt(MCRYPT_RIJNDAEL_128,$dKey,base64_decode($dStr),MCRYPT_MODE_ECB);

    $dec_s = strlen($decrypted);

    $padding = ord($decrypted[$dec_s-1]);

    $decrypted = substr($decrypted, 0, -$padding);

    return $decrypted;

}

<?php
class Crypt3Des {
var $key;
function Crypt3Des($key){
$this->key = $key;
}

function encrypt($input){
$size = mcrypt_get_block_size(MCRYPT_3DES,’ecb’);
$input = $this->pkcs5_pad($input, $size);
$key = str_pad($this->key,24,’0′);
$td = mcrypt_module_open(MCRYPT_3DES, ”, ‘ecb’, ”);
$iv = @mcrypt_create_iv (mcrypt_enc_get_iv_size($td),
MCRYPT_RAND);
@mcrypt_generic_init($td, $key, $iv);
$data = mcrypt_generic($td, $input);
mcrypt_generic_deinit($td);
mcrypt_module_close($td);
//$data = base64_encode($this->PaddingPKCS7($data));
$data = base64_encode($data);
return $data;
}

function decrypt($encrypted){
$encrypted = base64_decode($encrypted);
$key = str_pad($this->key,24,’0′);
$td = mcrypt_module_open(MCRYPT_3DES,”,’ecb’,”);
$iv =
@mcrypt_create_iv(mcrypt_enc_get_iv_size($td),MCRYPT_RAND);
$ks = mcrypt_enc_get_key_size($td);
@mcrypt_generic_init($td, $key, $iv);
$decrypted = mdecrypt_generic($td, $encrypted);
mcrypt_generic_deinit($td);
mcrypt_module_close($td);
$y=$this->pkcs5_unpad($decrypted);
return $y;
}

function pkcs5_pad ($text, $blocksize) {
$pad = $blocksize – (strlen($text) % $blocksize);
return $text . str_repeat(chr($pad), $pad);
}

function pkcs5_unpad($text){
$pad = ord($text{strlen($text)-1});
if ($pad > strlen($text)) {
   return false;
}
if (strspn($text, chr($pad), strlen($text) – $pad) != $pad){
   return false;
}
return substr($text, 0, -1 *
$pad);
}

function PaddingPKCS7($data) {
$block_size = mcrypt_get_block_size(MCRYPT_3DES,
MCRYPT_MODE_CBC);
$padding_char = $block_size – (strlen($data) % $block_size);
$data .= str_repeat(chr($padding_char),$padding_char);
return $data;
}
}

用法:

$crypt = new Crypt3Des(‘密钥’);
$a = ‘待加密字符串’;
$code = $crypt->encrypt($a);//加密
echo $crypt->decrypt($code);//解密