/**
* url_crypt加密算法的解密函数
*
* @param string $tpl 产品线的tpl标识
* @param string $key 加密所用的key
* @param string $hash 16进制密文字符串
* @return 加密的原文或者false
*/
public static function url_decrypt($tpl, $key, $hash)
{
if (empty($hash) || strlen($hash) <= 4) {
return false;
}
// first checek crc16
$hash = strtolower($hash);
$fcrypt_hstr = substr($hash, 0, -4);
$fcrypt_crc16 = intval(base_convert(substr($hash, -4), 16, 10));
// check crc16
if ($fcrypt_crc16 !== self::_crc16($fcrypt_hstr)) {
return false;
}
// decode hstr to binary str
// same use pack not hex2bin, nibble is not defined clearly
$fcrypt_hash = pack('H*', $fcrypt_hstr);
// decode hash to original stoken
return fcrypt_decode_hmac(self::_buildFcryptKey($tpl, $key), $fcrypt_hash);
}
/**
* @brief 解密图片id
* @param 加密前的字符串
* @return 正确返回pic_id,错误返回false
* @author wenweidong
* @date 2012/03/21 11:31:37
* @note
*/
public function decode_pic_url_crypt($strCrypt)
{
$data = pack('H*', $strCrypt);
$data = fcrypt_decode_hmac($this->crypt_key, $data);
if (strlen($data) == 8) {
$result = $this->unpackUInt32(substr($data, 0, 4));
$intID1 = $result;
$result = $this->unpackUInt32(substr($data, 4, 4));
$intID2 = $result;
return $intID2;
} else {
if (strlen($data) == 16) {
$intID1 = $this->unpackUInt64(substr($data, 0, 8));
$intID2 = $this->unpackUInt64(substr($data, 8, 8));
return $intID2;
} else {
return false;
}
}
}
protected function _readResponse($handler)
{
//读取nshead
$headbuf = $handler->read(36);
if (!$headbuf) {
$this->_log("read nshead failed\n");
$this->_last_errno = ZCACHE_CLIENT_ERR_READ;
$this->_last_errmsg = "net read err";
return NULL;
}
//解析nshead
$head = zcache_split_nshead($headbuf);
if (!isset($head['body_len'])) {
$this->_log("no body_len in nshead\n");
$this->_last_errno = ZCACHE_CLIENT_ERR_NSHEAD;
$this->_last_errmsg = "nshead err";
return NULL;
}
//读取数据包内容
$retbuffer = $handler->read($head['body_len']);
if (!$retbuffer) {
$this->_log("read nsbody " . $head['body_len'] . " failed\n");
$this->_last_errno = ZCACHE_CLIENT_ERR_READ;
$this->_last_errmsg = "net read err";
return NULL;
}
if ($head['reserverd']) {
$decrypt_data = fcrypt_decode_hmac('key', $retbuffer);
//$this->_log("fcrypt_decode_hmac: " . strlen($retbuffer) . " " . strlen($decrypt_data) );
return $decrypt_data;
} else {
return $retbuffer;
}
}
