Implement RakNet protocol version handling

src/generic/Session.php

@@ -53,6 +53,8 @@ abstract class Session{
 
 	private int $id;
 
+	private int $protocol;
+
 	private float $lastUpdate;
 	private float $disconnectionTime = 0;
 
@@ -75,6 +77,7 @@ public function __construct(
 		InternetAddress $address,
 		int $clientId,
 		int $mtuSize,
+		int $protocol,
 		int $recvMaxSplitParts = PHP_INT_MAX,
 		int $recvMaxConcurrentSplits = PHP_INT_MAX
 	){
@@ -84,6 +87,7 @@ public function __construct(
 		$this->logger = new \PrefixedLogger($logger, "Session: " . $address->toString());
 		$this->address = $address;
 		$this->id = $clientId;
+		$this->protocol = $protocol;
 
 		$this->lastUpdate = microtime(true);
 
@@ -167,6 +171,10 @@ public function getID() : int{
 		return $this->id;
 	}
 
+	public function getProtocol() : int{
+		return $this->protocol;
+	}
+
 	public function getState() : int{
 		return $this->state;
 	}

src/server/PendingConnection.php

@@ -0,0 +1,36 @@
+<?php
+
+/*
+ * This file is part of RakLib.
+ * Copyright (C) 2014-2022 PocketMine Team <https://github.com/pmmp/RakLib>
+ *
+ * RakLib is not affiliated with Jenkins Software LLC nor RakNet.
+ *
+ * RakLib is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ */
+
+declare(strict_types=1);
+
+namespace raklib\server;
+
+class PendingConnection{
+
+	private float $createdAt;
+
+	public function __construct(
+		private int $protocol
+	){
+		$this->createdAt = microtime(true);
+	}
+
+	public function getProtocol() : int{
+		return $this->protocol;
+	}
+
+	public function getCreatedAt() : float{
+		return $this->createdAt;
+	}
+}

src/server/Server.php

@@ -182,6 +182,7 @@ private function tick() : void{
 				$this->removeSessionInternal($session);
 			}
 		}
+		$this->unconnectedMessageHandler->update($time);
 
 		$this->ipSec = [];
 
@@ -410,7 +411,7 @@ public function sessionExists(InternetAddress $address) : bool{
 		return isset($this->sessionsByAddress[$address->toString()]);
 	}
 
-	public function createSession(InternetAddress $address, int $clientId, int $mtuSize) : ServerSession{
+	public function createSession(InternetAddress $address, int $clientId, int $mtuSize, int $protocol) : ServerSession{
 		$existingSession = $this->sessionsByAddress[$address->toString()] ?? null;
 		if($existingSession !== null){
 			$existingSession->forciblyDisconnect(DisconnectReason::CLIENT_RECONNECT);
@@ -424,7 +425,7 @@ public function createSession(InternetAddress $address, int $clientId, int $mtuS
 			$this->nextSessionId &= 0x7fffffff; //we don't expect more than 2 billion simultaneous connections, and this fits in 4 bytes
 		}
 
-		$session = new ServerSession($this, $this->logger, clone $address, $clientId, $mtuSize, $this->nextSessionId, $this->recvMaxSplitParts, $this->recvMaxConcurrentSplits);
+		$session = new ServerSession($this, $this->logger, clone $address, $clientId, $mtuSize, $protocol, $this->nextSessionId, $this->recvMaxSplitParts, $this->recvMaxConcurrentSplits);
 		$this->sessionsByAddress[$address->toString()] = $session;
 		$this->sessions[$this->nextSessionId] = $session;
 		$this->logger->debug("Created session for $address with MTU size $mtuSize");
@@ -438,7 +439,7 @@ private function removeSessionInternal(ServerSession $session) : void{
 
 	public function openSession(ServerSession $session) : void{
 		$address = $session->getAddress();
-		$this->eventListener->onClientConnect($session->getInternalId(), $address->getIp(), $address->getPort(), $session->getID());
+		$this->eventListener->onClientConnect($session->getInternalId(), $address->getIp(), $address->getPort(), $session->getID(), $session->getProtocol());
 	}
 
 	private function checkSessions() : void{

src/server/ServerEventListener.php

@@ -20,7 +20,7 @@
 
 interface ServerEventListener{
 
-	public function onClientConnect(int $sessionId, string $address, int $port, int $clientID) : void;
+	public function onClientConnect(int $sessionId, string $address, int $port, int $clientID, int $protocol) : void;
 
 	/**
 	 * @param int $reason one of the DisconnectReason constants

src/server/ServerSession.php

@@ -40,13 +40,14 @@ public function __construct(
 		InternetAddress $address,
 		int $clientId,
 		int $mtuSize,
+		int $protocol,
 		int $internalId,
 		int $recvMaxSplitParts = self::DEFAULT_MAX_SPLIT_PART_COUNT,
 		int $recvMaxConcurrentSplits = self::DEFAULT_MAX_CONCURRENT_SPLIT_COUNT
 	){
 		$this->server = $server;
 		$this->internalId = $internalId;
-		parent::__construct($logger, $address, $clientId, $mtuSize, $recvMaxSplitParts, $recvMaxConcurrentSplits);
+		parent::__construct($logger, $address, $clientId, $mtuSize, $protocol, $recvMaxSplitParts, $recvMaxConcurrentSplits);
 	}
 
 	/**

src/server/UnconnectedMessageHandler.php

@@ -42,6 +42,8 @@ class UnconnectedMessageHandler{
 	 * @phpstan-var \SplFixedArray<OfflineMessage>
 	 */
 	private \SplFixedArray $packetPool;
+	/** @var PendingConnection[] */
+	private array $pendingConnections = [];
 
 	public function __construct(
 		private Server $server,
@@ -81,6 +83,8 @@ private function handle(OfflineMessage $packet, InternetAddress $address) : bool
 				$this->server->sendPacket(IncompatibleProtocolVersion::create($this->protocolAcceptor->getPrimaryVersion(), $this->server->getID()), $address);
 				$this->server->getLogger()->notice("Refused connection from $address due to incompatible RakNet protocol version (version $packet->protocol)");
 			}else{
+				$this->pendingConnections[$address->toString()] = new PendingConnection($packet->protocol);
+
 				//IP header size (20 bytes) + UDP header size (8 bytes)
 				$this->server->sendPacket(OpenConnectionReply1::create($this->server->getID(), false, $packet->mtuSize + 28), $address);
 			}
@@ -97,9 +101,17 @@ private function handle(OfflineMessage $packet, InternetAddress $address) : bool
 					$this->server->getLogger()->debug("Not creating session for $address due to session already opened");
 					return true;
 				}
+				if(!isset($this->pendingConnections[$address->toString()])){
+					// we should always except OpenConnectionRequest1 before OpenConnectionRequeqst2
+					$this->server->getLogger()->debug("Not creating session for $address due to no pending connection");;
+					return true;
+				}
+				$pendingConnection = $this->pendingConnections[$address->toString()];
+				unset($this->pendingConnections[$address->toString()]);
+
 				$mtuSize = min($packet->mtuSize, $this->server->getMaxMtuSize()); //Max size, do not allow creating large buffers to fill server memory
 				$this->server->sendPacket(OpenConnectionReply2::create($this->server->getID(), $address, $mtuSize, false), $address);
-				$this->server->createSession($address, $packet->clientID, $mtuSize);
+				$this->server->createSession($address, $packet->clientID, $mtuSize, $pendingConnection->getProtocol());
 			}else{
 				$this->server->getLogger()->debug("Not creating session for $address due to mismatched port, expected " . $this->server->getPort() . ", got " . $packet->serverAddress->getPort());
 			}
@@ -110,6 +122,15 @@ private function handle(OfflineMessage $packet, InternetAddress $address) : bool
 		return true;
 	}
 
+	public function update(float $time) : void{
+		foreach($this->pendingConnections as $address => $pendingConnection){
+			if($pendingConnection->getCreatedAt() + 10 < $time){
+				$this->server->getLogger()->debug("Timed out pending connection from $address");
+				unset($this->pendingConnections[$address]);
+			}
+		}
+	}
+
 	/**
 	 * @phpstan-param class-string<OfflineMessage> $class
 	 */