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Merged
WyriHaximus merged 1 commit into from
Jan 30, 2019
Merged

Support parsing authority and additional records from DNS response #123

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34 changes: 34 additions & 0 deletions src/Model/Message.php
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Original file line number Diff line number Diff line change
Expand Up @@ -100,10 +100,44 @@ private static function generateId()
return mt_rand(0, 0xffff);
}

/**
* @var HeaderBag
*/
public $header;

/**
* This should be an array of Query objects. For BC reasons, this currently
* references a nested array with a structure that results from casting the
* Query objects to an array:
*
* ```php
* $questions = array(
* array(
* 'name' => 'reactphp.org',
* 'type' => Message::TYPE_A,
* 'class' => Message::CLASS_IN
* )
* );
* ```
*
* @var array
* @see Query
*/
public $questions = array();

/**
* @var Record[]
*/
public $answers = array();

/**
* @var Record[]
*/
public $authority = array();

/**
* @var Record[]
*/
public $additional = array();

/**
Expand Down
7 changes: 7 additions & 0 deletions src/Model/Record.php
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Original file line number Diff line number Diff line change
Expand Up @@ -87,6 +87,13 @@ class Record
*/
public $data;

/**
* @param string $name
* @param int $type
* @param int $class
* @param int $ttl
* @param string|string[]|array $data
*/
public function __construct($name, $type, $class, $ttl = 0, $data = null)
{
$this->name = $name;
Expand Down
73 changes: 58 additions & 15 deletions src/Protocol/Parser.php
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Original file line number Diff line number Diff line change
Expand Up @@ -55,9 +55,33 @@ private function parse($data, Message $message)
}
}

if ($message->header->get('anCount') != count($message->answers)) {
if (!$this->parseAnswer($message)) {
// parse all answer records
for ($i = $message->header->get('anCount'); $i > 0; --$i) {
$record = $this->parseRecord($message);
if ($record === null) {
return;
} else {
$message->answers[] = $record;
}
}

// parse all authority records
for ($i = $message->header->get('nsCount'); $i > 0; --$i) {
$record = $this->parseRecord($message);
if ($record === null) {
return;
} else {
$message->authority[] = $record;
}
}

// parse all additional records
for ($i = $message->header->get('arCount'); $i > 0; --$i) {
$record = $this->parseRecord($message);
if ($record === null) {
return;
} else {
$message->additional[] = $record;
}
}

Expand Down Expand Up @@ -87,7 +111,6 @@ public function parseHeader(Message $message)
$vars = compact('id', 'qdCount', 'anCount', 'nsCount', 'arCount',
'qr', 'opcode', 'aa', 'tc', 'rd', 'ra', 'z', 'rcode');


foreach ($vars as $name => $value) {
$message->header->set($name, $value);
}
Expand Down Expand Up @@ -123,14 +146,42 @@ public function parseQuestion(Message $message)
return $message;
}

/**
* recursively parse all answers from the message data into message answer records
*
* @param Message $message
* @return ?Message returns the updated message on success or null if the data is invalid/incomplete
* @deprecated unused, exists for BC only
* @codeCoverageIgnore
*/
public function parseAnswer(Message $message)
{
$record = $this->parseRecord($message);
if ($record === null) {
return null;
}

$message->answers[] = $record;

if ($message->header->get('anCount') != count($message->answers)) {
return $this->parseAnswer($message);
}

return $message;
}

/**
* @param Message $message
* @return ?Record returns parsed Record on success or null if data is invalid/incomplete
*/
private function parseRecord(Message $message)
{
$consumed = $message->consumed;

list($name, $consumed) = $this->readDomain($message->data, $consumed);

if ($name === null || !isset($message->data[$consumed + 10 - 1])) {
return;
return null;
}

list($type, $class) = array_values(unpack('n*', substr($message->data, $consumed, 4)));
Expand All @@ -148,7 +199,7 @@ public function parseAnswer(Message $message)
$consumed += 2;

if (!isset($message->data[$consumed + $rdLength - 1])) {
return;
return null;
}

$rdata = null;
Expand Down Expand Up @@ -221,20 +272,12 @@ public function parseAnswer(Message $message)

// ensure parsing record data consumes expact number of bytes indicated in record length
if ($consumed !== $expected || $rdata === null) {
return;
return null;
}

$message->consumed = $consumed;

$record = new Record($name, $type, $class, $ttl, $rdata);

$message->answers[] = $record;

if ($message->header->get('anCount') != count($message->answers)) {
return $this->parseAnswer($message);
}

return $message;
return new Record($name, $type, $class, $ttl, $rdata);
}

private function readDomain($data, $consumed)
Expand Down
123 changes: 122 additions & 1 deletion tests/Protocol/ParserTest.php
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Original file line number Diff line number Diff line change
Expand Up @@ -439,7 +439,7 @@ public function testParseSRVResponse()
);
}

public function testParseResponseWithTwoAnswers()
public function testParseMessageResponseWithTwoAnswers()
{
$data = "";
$data .= "bc 73 81 80 00 01 00 02 00 00 00 00"; // header
Expand Down Expand Up @@ -481,6 +481,95 @@ public function testParseResponseWithTwoAnswers()
$this->assertSame('193.223.78.152', $response->answers[1]->data);
}

public function testParseMessageResponseWithTwoAuthorityRecords()
{
$data = "";
$data .= "bc 73 81 80 00 01 00 00 00 02 00 00"; // header
$data .= "02 69 6f 0d 77 68 6f 69 73 2d 73 65 72 76 65 72 73 03 6e 65 74 00";
// question: io.whois-servers.net
$data .= "00 01 00 01"; // question: type A, class IN
$data .= "c0 0c"; // authority: offset pointer to io.whois-servers.net
$data .= "00 05 00 01"; // authority: type CNAME, class IN
$data .= "00 00 00 29"; // authority: ttl 41
$data .= "00 0e"; // authority: rdlength 14
$data .= "05 77 68 6f 69 73 03 6e 69 63 02 69 6f 00"; // authority: rdata whois.nic.io
$data .= "c0 32"; // authority: offset pointer to whois.nic.io
$data .= "00 01 00 01"; // authority: type CNAME, class IN
$data .= "00 00 0d f7"; // authority: ttl 3575
$data .= "00 04"; // authority: rdlength 4
$data .= "c1 df 4e 98"; // authority: rdata 193.223.78.152

$data = $this->convertTcpDumpToBinary($data);

$response = $this->parser->parseMessage($data);

$this->assertCount(1, $response->questions);
$this->assertSame('io.whois-servers.net', $response->questions[0]['name']);
$this->assertSame(Message::TYPE_A, $response->questions[0]['type']);
$this->assertSame(Message::CLASS_IN, $response->questions[0]['class']);

$this->assertCount(0, $response->answers);

$this->assertCount(2, $response->authority);

$this->assertSame('io.whois-servers.net', $response->authority[0]->name);
$this->assertSame(Message::TYPE_CNAME, $response->authority[0]->type);
$this->assertSame(Message::CLASS_IN, $response->authority[0]->class);
$this->assertSame(41, $response->authority[0]->ttl);
$this->assertSame('whois.nic.io', $response->authority[0]->data);

$this->assertSame('whois.nic.io', $response->authority[1]->name);
$this->assertSame(Message::TYPE_A, $response->authority[1]->type);
$this->assertSame(Message::CLASS_IN, $response->authority[1]->class);
$this->assertSame(3575, $response->authority[1]->ttl);
$this->assertSame('193.223.78.152', $response->authority[1]->data);
}

public function testParseMessageResponseWithAnswerAndAdditionalRecord()
{
$data = "";
$data .= "bc 73 81 80 00 01 00 01 00 00 00 01"; // header
$data .= "02 69 6f 0d 77 68 6f 69 73 2d 73 65 72 76 65 72 73 03 6e 65 74 00";
// question: io.whois-servers.net
$data .= "00 01 00 01"; // question: type A, class IN
$data .= "c0 0c"; // answer: offset pointer to io.whois-servers.net
$data .= "00 05 00 01"; // answer: type CNAME, class IN
$data .= "00 00 00 29"; // answer: ttl 41
$data .= "00 0e"; // answer: rdlength 14
$data .= "05 77 68 6f 69 73 03 6e 69 63 02 69 6f 00"; // answer: rdata whois.nic.io
$data .= "c0 32"; // additional: offset pointer to whois.nic.io
$data .= "00 01 00 01"; // additional: type CNAME, class IN
$data .= "00 00 0d f7"; // additional: ttl 3575
$data .= "00 04"; // additional: rdlength 4
$data .= "c1 df 4e 98"; // additional: rdata 193.223.78.152

$data = $this->convertTcpDumpToBinary($data);

$response = $this->parser->parseMessage($data);

$this->assertCount(1, $response->questions);
$this->assertSame('io.whois-servers.net', $response->questions[0]['name']);
$this->assertSame(Message::TYPE_A, $response->questions[0]['type']);
$this->assertSame(Message::CLASS_IN, $response->questions[0]['class']);

$this->assertCount(1, $response->answers);

$this->assertSame('io.whois-servers.net', $response->answers[0]->name);
$this->assertSame(Message::TYPE_CNAME, $response->answers[0]->type);
$this->assertSame(Message::CLASS_IN, $response->answers[0]->class);
$this->assertSame(41, $response->answers[0]->ttl);
$this->assertSame('whois.nic.io', $response->answers[0]->data);

$this->assertCount(0, $response->authority);
$this->assertCount(1, $response->additional);

$this->assertSame('whois.nic.io', $response->additional[0]->name);
$this->assertSame(Message::TYPE_A, $response->additional[0]->type);
$this->assertSame(Message::CLASS_IN, $response->additional[0]->class);
$this->assertSame(3575, $response->additional[0]->ttl);
$this->assertSame('193.223.78.152', $response->additional[0]->data);
}

public function testParseNSResponse()
{
$data = "";
Expand Down Expand Up @@ -706,6 +795,38 @@ public function testParseIncompleteAnswerFieldsThrows()
$this->parser->parseMessage($data);
}

/**
* @expectedException InvalidArgumentException
*/
public function testParseMessageResponseWithIncompleteAuthorityRecordThrows()
{
$data = "";
$data .= "72 62 81 80 00 01 00 00 00 01 00 00"; // header
$data .= "04 69 67 6f 72 02 69 6f 00"; // question: igor.io
$data .= "00 01 00 01"; // question: type A, class IN
$data .= "c0 0c"; // authority: offset pointer to igor.io

$data = $this->convertTcpDumpToBinary($data);

$this->parser->parseMessage($data);
}

/**
* @expectedException InvalidArgumentException
*/
public function testParseMessageResponseWithIncompleteAdditionalRecordThrows()
{
$data = "";
$data .= "72 62 81 80 00 01 00 00 00 00 00 01"; // header
$data .= "04 69 67 6f 72 02 69 6f 00"; // question: igor.io
$data .= "00 01 00 01"; // question: type A, class IN
$data .= "c0 0c"; // additional: offset pointer to igor.io

$data = $this->convertTcpDumpToBinary($data);

$this->parser->parseMessage($data);
}

/**
* @expectedException InvalidArgumentException
*/
Expand Down