des加密

function des_encrypt($str, $key) {
    $block = mcrypt_get_block_size('des', 'ecb');
    $pad = $block - (strlen($str) % $block);
    $str .= str_repeat(chr($pad), $pad);
    return mcrypt_encrypt(MCRYPT_DES, $key, $str, MCRYPT_MODE_ECB);
}

des解密

function des_decrypt($str, $key) {
    $str = mcrypt_decrypt(MCRYPT_DES, $key, $str, MCRYPT_MODE_ECB);
    $len = strlen($str);
    $block = mcrypt_get_block_size('des', 'ecb');
    $pad = ord($str[$len - 1]);
    return substr($str, 0, $len - $pad);
}