/**
* Decode the header section of the message
*
* @param \LibDNS\Decoder\DecodingContext $decodingContext
* @param \LibDNS\Messages\Message $message
* @throws \UnexpectedValueException When the header section is invalid
*/
private function decodeHeader(DecodingContext $decodingContext, Message $message)
{
$header = unpack('nid/nmeta/nqd/nan/nns/nar', $this->readDataFromPacket($decodingContext->getPacket(), 12));
if (!$header) {
throw new \UnexpectedValueException('Decode error: Header unpack failed');
}
$message->setID($header['id']);
$message->setType(($header['meta'] & 0b1000000000000000) >> 15);
$message->setOpCode(($header['meta'] & 0b111100000000000) >> 11);
$message->isAuthoritative(($header['meta'] & 0b10000000000) >> 10);
$message->isTruncated(($header['meta'] & 0b1000000000) >> 9);
$message->isRecursionDesired(($header['meta'] & 0b100000000) >> 8);
$message->isRecursionAvailable(($header['meta'] & 0b10000000) >> 7);
$message->setResponseCode($header['meta'] & 0b1111);
$decodingContext->setExpectedQuestionRecords($header['qd']);
$decodingContext->setExpectedAnswerRecords($header['an']);
$decodingContext->setExpectedAuthorityRecords($header['ns']);
$decodingContext->setExpectedAdditionalRecords($header['ar']);
}
/**
* Encode a Message to raw network data
*
* @param \LibDNS\Messages\Message $message The Message to encode
* @param bool $compress Enable message compression
* @return string
*/
public function encode(Message $message, $compress = true)
{
$packet = $this->packetFactory->create();
$encodingContext = $this->encodingContextFactory->create($packet, $compress);
foreach ($message->getQuestionRecords() as $record) {
/** @var \LibDNS\Records\Question $record */
$this->encodeQuestionRecord($encodingContext, $record);
}
foreach ($message->getAnswerRecords() as $record) {
/** @var \LibDNS\Records\Resource $record */
$this->encodeResourceRecord($encodingContext, $record);
}
foreach ($message->getAuthorityRecords() as $record) {
/** @var \LibDNS\Records\Resource $record */
$this->encodeResourceRecord($encodingContext, $record);
}
foreach ($message->getAdditionalRecords() as $record) {
/** @var \LibDNS\Records\Resource $record */
$this->encodeResourceRecord($encodingContext, $record);
}
return $this->encodeHeader($encodingContext, $message) . $packet->read($packet->getLength());
}
