PHP中加密解密函数与DES加密解密实例

/*
*功能：对字符串进行加密处理
*参数一：需要加密的内容
*参数二：密钥
*/
function passport_encrypt($str,$key){ //加密函数
?srand((double)microtime() * 1000000);
?$encrypt_key=md5(rand(0,32000));
?$ctr=0;
?$tmp='';
?for($i=0;$i<strlen($str);$i++){
? $ctr=$ctr==strlen($encrypt_key)?0:$ctr;
? $tmp.=$encrypt_key[$ctr].($str[$i] ^ $encrypt_key[$ctr++]);
?}
?return base64_encode(passport_key($tmp,$key));
}

/*
*功能：对字符串进行解密处理
*参数一：需要解密的密文
*参数二：密钥
*/
function passport_decrypt($str,$key){ //解密函数
?$str=passport_key(base64_decode($str),$key);
?$tmp='';
?for($i=0;$i<strlen($str);$i++){
? $md5=$str[$i];
? $tmp.=$str[++$i] ^ $md5;
?}
?return $tmp;
}

/*
*辅助函数
*/
function passport_key($str,$encrypt_key){
?$encrypt_key=md5($encrypt_key);
?$ctr=0;
?$tmp='';
?for($i=0;$i<strlen($str);$i++){
? $ctr=$ctr==strlen($encrypt_key)?0:$ctr;
? $tmp.=$str[$i] ^ $encrypt_key[$ctr++];
?}
?return $tmp;
}

$str='作者：www.aspzz.cn';
$key='123456';
$encrypt=passport_encrypt($str,$key);
$decrypt=passport_decrypt($encrypt,$key);
echo '原文：',$str."<br><hr>";
echo '密文：',$encrypt."<br><hr>";
echo '译文：',$decrypt."<br><hr>";

<?php
class DES
{
?var $key;
?var $iv; //偏移量
?
?function DES( $key,$iv=0 ) {
?//key长度8例如:1234abcd
? $this->key = $key;
? if( $iv == 0 ) {
?? $this->iv = $key;
? } else {
?? $this->iv = $iv; //mcrypt_create_iv ( mcrypt_get_block_size (MCRYPT_DES,MCRYPT_MODE_CBC),MCRYPT_DEV_RANDOM );
? }
?}
?
?function encrypt($str) {
?//加密,返回大写十六进制字符串
? $size = mcrypt_get_block_size ( MCRYPT_DES,MCRYPT_MODE_CBC );
? $str = $this->pkcs5Pad ( $str,$size );
? return strtoupper( bin2hex( mcrypt_cbc(MCRYPT_DES,$this->key,$str,MCRYPT_ENCRYPT,$this->iv ) ) );
?}
?
?function decrypt($str) {
?//解密
? $strBin = $this->hex2bin( strtolower( $str ) );
? $str = mcrypt_cbc( MCRYPT_DES,$strBin,MCRYPT_DECRYPT,$this->iv );
? $str = $this->pkcs5Unpad( $str );
? return $str;
?}
?
?function hex2bin($hexData) {
? $binData = "";
? for($i = 0; $i < strlen ( $hexData ); $i += 2) {
?? $binData .= chr ( hexdec ( substr ( $hexData,$i,2 ) ) );
? }
? return $binData;
?}
?
?function pkcs5Pad($text,$blocksize) {
? $pad = $blocksize - (strlen ( $text ) % $blocksize);
? return $text . str_repeat ( chr ( $pad ),$pad );
?}
?
?function pkcs5Unpad($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,- 1 * $pad );
?}
}
?>

$str = '12345678';
$key = '1234abcd';
$crypt = new DES($key);
$mstr = $crypt->encrypt($str);
$str = $crypt->decrypt($mstr);
echo? $str.' <=> '.$mstr;

/**
*加密需通过get方式在url中传递的参数
*/
function args_encode($data) {
if(is_array($data)) {
$string = http_build_query($data);
return base64_encode($string);
} else {
return false;
}
}

/**
*获取url中get方式传递的参数
*/
function getargs() {
$string = base64_decode($_GET['args']);
parse_str($string,$g);
return $g;
}PHP实战