PHP中DES加密解密实例代码

DES加解密类文件：

<?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, $this->key, $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, 0, - 1 * $pad );

 }

}

?>

$str = "12345678";

$key = "1234abcd";

$crypt = new DES($key);

$mstr = $crypt->encrypt($str); //加密

$str = $crypt->decrypt($mstr); //解密

echo  $str." <=> ".$mstr;