rcon.funcs.php

<?php

function EncodeHeader($isFromServer, $isResponse, $sequence)
{
	$header = $sequence & 0x3fffffff;
	
	if ($isFromServer) {
		$header += 0x80000000;
	}
	
	if ($isResponse) {
		$header += 0x40000000;
	}
	
	return pack('I', $header);
}

function DecodeHeader($data)
{
	$header = unpack('I', mb_substr($data, 0, 4));
	
	return array($header & 0x80000000, $header & 0x40000000, $header & 0x3fffffff);
}

function EncodeInt32($size)
{
	return pack('I', $size);
}

function DecodeInt32($data)
{
	$decode = unpack('I', mb_substr($data, 0, 4));
	
	return $decode[1];
}

function EncodeWords($words)
{
	$size = 0;
	$encodedWords = '';
	
	foreach ($words as $word) {
		$encodedWords .= EncodeInt32(strlen($word));
		$encodedWords .= $word;
		$encodedWords .= "\x00";
		$size += strlen($word) + 5;
	}
	
	return array($size, $encodedWords);
}

function DecodeWords($size, $data)
{
	$numWords = DecodeInt32($data);
	$words = array();
	$offset = 0;
	while ($offset < $size) {
		$wordLen = DecodeInt32(mb_substr($data, $offset, 4));
		$word = mb_substr($data, $offset + 4, $wordLen);
		array_push($words, $word);
		$offset += $wordLen + 5;
	}
	
	return $words;
}

function EncodePacket($isFromServer, $isResponse, $sequence, $words)
{
	$encodedHeader = EncodeHeader($isFromServer, $isResponse, $sequence);
	$encodedNumWords = EncodeInt32(count($words));
	list($wordsSize, $encodedWords) = EncodeWords($words);
	$encodedSize = EncodeInt32($wordsSize + 12);
	
	return $encodedHeader . $encodedSize . $encodedNumWords . $encodedWords;
}

function DecodePacket($data)
{
	list($isFromServer, $isResponse, $sequence) = DecodeHeader($data);
	$wordsSize = DecodeInt32(mb_substr($data, 4, 4)) - 12;
	$words = DecodeWords($wordsSize, mb_substr($data, 12));
	
	return array($isFromServer, $isResponse, $sequence, $words);
}

function EncodeClientRequest($string)
{
	global $clientSequenceNr;
	
	// string splitting
	if ((strpos($string, '"') !== FALSE) or (strpos($string, '\'') !== FALSE)) {
		$words = preg_split('/["\']/', $string);

		for ($i=0; $i < count($words); $i++) { 
			$words[$i] = trim($words[$i]);
		}
	} else {
		$words = preg_split('/\s+/', $string);
	}
	
	$packet = EncodePacket(False, False, $clientSequenceNr, $words);
	$clientSequenceNr = ($clientSequenceNr + 1) & 0x3fffffff;
	
	return $packet;
}

function EncodeClientResponse($sequence, $words)
{
	return EncodePacket(True, True, $sequence, $words);
}

function containsCompletePacket($data)
{
	if (mb_strlen($data) < 8) {
		return False;
	}
	
	if (mb_strlen($data) < DecodeInt32(mb_substr($data, 4, 4))) {
		return False;
	}
	
	return True;
}

function receivePacket(&$socket)
{
	$receiveBuffer = '';	
	while (!containsCompletePacket($receiveBuffer)) {
		global $receiveBuffer;
		
		if (($receiveBuffer .= socket_read($socket, 4096)) === FALSE) {
			echo "Socket error: " . socket_strerror(socket_last_error($socket)) . "\n";
			socket_close($socket);
			exit;
		}
	}
	
	$packetSize = DecodeInt32(mb_substr($receiveBuffer, 4, 4));
	$packet = mb_substr($receiveBuffer, 0, $packetSize);
	$receiveBuffer = mb_substr($receiveBuffer, $packetSize);
	
	return array($packet, $receiveBuffer);
}

function printPacket($packet)
{
	if ($packet[0]) {
		echo "IsFromServer, $packet[0] ";
	} else {
		echo "IsFromClient, ";
	}
	
	if ($packet[1]) {
		echo "Response, $packet[1] ";
	} else {
		echo "Request, ";
	}
	
	echo "Sequence: $packet[2]";
	
	if ($packet[3]) {
		echo " Words:";
		foreach ($packet[3] as $word) {
			echo " \"$word\"";
		}
	}
}

// Hashed password helper functions
function hexstr($hexstr)
{
	$hexstr = str_replace(' ', '', $hexstr);
	$hexstr = str_replace('\x', '', $hexstr);
	$retstr = pack('H*', $hexstr);
	return $retstr;
}

function strhex($string)
{
	$hexstr = unpack('H*', $string);
	return array_shift($hexstr);
}

function generatePasswordHash($salt, $password)
{
	$salt = hexstr($salt);
	$hashedPassword = md5($salt . $password, TRUE);
	
	return strtoupper(strhex($hashedPassword));
}

/**
 * Main RCON Command. Call this to send a command to the server.
 * Arguments: socket, command to send
 *
 * @return array of words; server's response
 **/
function rconCommand(&$socket, $string)
{
	if ((socket_write($socket, EncodeClientRequest($string))) === FALSE) {
		echo "Socket error: " . socket_strerror(socket_last_error($socket)) . "\n";
		socket_close($socket);
		exit;
	}
	
	list($packet, $receiveBuffer) = receivePacket($socket);
	list($isFromServer, $isResponse, $sequence, $words) = DecodePacket($packet);
	
	return $words;
}

// same as rconCommand, but prints packet for debugging
function rconCommandPrintPacket(&$socket, $string)
{
	if ((socket_write($socket, EncodeClientRequest($string))) === FALSE) {
		echo "Socket error: " . socket_strerror(socket_last_error($socket)) . "\n";
		socket_close($socket);
		exit;
	}
	
	list($packet, $receiveBuffer) = receivePacket($socket);
	printPacket(DecodePacket($packet));
	list($isFromServer, $isResponse, $sequence, $words) = DecodePacket($packet);
	
	return $words;
}

?>