这与 mysql aes 完全配合使用,即使是长密钥。
<?php 
function mysql_aes_decrypt($val,$ky) 
{ 
 $key="\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"; 
 for($a=0;$a<strlen($ky);$a++) 
 $key[$a%16]=chr(ord($key[$a%16]) ^ ord($ky[$a])); 
 $mode = MCRYPT_MODE_ECB; 
 $enc = MCRYPT_RIJNDAEL_128; 
 $dec = @mcrypt_decrypt($enc, $key, $val, $mode, @mcrypt_create_iv( @mcrypt_get_iv_size($enc, $mode), MCRYPT_DEV_URANDOM ) ); 
 return rtrim($dec,(( ord(substr($dec,strlen($dec)-1,1))>=0 and ord(substr($dec, strlen($dec)-1,1))<=16)? chr(ord( substr($dec,strlen($dec)-1,1))):null)); 
} 
 
function mysql_aes_encrypt($val,$ky) 
{ 
 $key="\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"; 
 for($a=0;$a<strlen($ky);$a++) 
 $key[$a%16]=chr(ord($key[$a%16]) ^ ord($ky[$a])); 
 $mode=MCRYPT_MODE_ECB; 
 $enc=MCRYPT_RIJNDAEL_128; 
 $val=str_pad($val, (16*(floor(strlen($val) / 16)+(strlen($val) % 16==0?2:1))), chr(16-(strlen($val) % 16))); 
 return mcrypt_encrypt($enc, $key, $val, $mode, mcrypt_create_iv( mcrypt_get_iv_size($enc, $mode), MCRYPT_DEV_URANDOM)); 
} 
?>