From b6455c7d48719eceb1252c80fc16d18438728c82 Mon Sep 17 00:00:00 2001
From: Simon Rettberg
Date: Tue, 7 Mar 2023 12:17:27 +0100
Subject: Add more debug output to discovery part

---
 src/client/net/serverdiscovery.cpp   | 10 ++++++++--
 src/server/net/discoverylistener.cpp | 14 ++++++++++----
 src/server/serverapp/serverapp.cpp   |  2 +-
 3 files changed, 19 insertions(+), 7 deletions(-)

diff --git a/src/client/net/serverdiscovery.cpp b/src/client/net/serverdiscovery.cpp
index efae165..5076a8b 100644
--- a/src/client/net/serverdiscovery.cpp
+++ b/src/client/net/serverdiscovery.cpp
@@ -106,7 +106,7 @@ void ServerDiscovery::doDiscovery()
 
 	// Check if specifig manager IP is given. If not broadcast in whole network.
 	if (_mgrIP != QHostAddress::Null) {
-		qDebug() << "Broadcasting to " << _mgrIP.toString();
+		qDebug() << "Sending discovery to " << _mgrIP.toString();
 		if (!_packet.writeMessage(&_discoverySocket, _mgrIP, SERVICE_DISCOVERY_PORT))
 			qDebug("Failed");
 	} else {
@@ -151,8 +151,10 @@ void ServerDiscovery::onUdpReadyRead()
 			continue;
 
 		_packet.reset();
-		if (_packet.readMessage(data, quint32(size)) != NM_READ_OK)
+		if (_packet.readMessage(data, quint32(size)) != NM_READ_OK) {
+			qDebug() << "Corrupt discovery reply from" << addr.toString();
 			continue;
+		}
 
 		// Valid packet, process it:
 		const QByteArray hash(_packet.getFieldBytes(_HASH));
@@ -162,6 +164,7 @@ void ServerDiscovery::onUdpReadyRead()
 
 		// Check if the source IP of the packet matches any of the addresses given in the IP list
 		if (!Network::isAddressInList(QString::fromUtf8(iplist), addr.toString())) {
+			qDebug() << "Received bogus discovery reply from" << addr.toString() << "... Not in" << iplist;
 			++_ipErrorCount;
 			emit error(ErrorType::InvalidIpList, _hashErrorCount);
 			continue;
@@ -170,6 +173,7 @@ void ServerDiscovery::onUdpReadyRead()
 		// If so, check if the submitted hash seems valid
 		if (genSha1(&_nameBytes, &_salt2, &iplist, &port, &cert) != hash && _mgrIP != addr) {
 			// did not match local session name, or other data was spoofed
+			qDebug() << "Received bogus session name in discovery reply from" << addr.toString();
 			++_hashErrorCount;
 			emit error(ErrorType::InvalidHash, _ipErrorCount);
 			continue;
@@ -184,6 +188,8 @@ void ServerDiscovery::onUdpReadyRead()
 		const ushort iport = QString::fromUtf8(port).toUShort(&ok);
 		if (ok) {
 			emit serverDetected(addr.toString(), quint16(iport), _nameBytes, cert, (_mgrIP == addr));
+		} else {
+			qDebug() << "... but server advertises unparsable port" << port;
 		}
 
 		// Stop the discovery
diff --git a/src/server/net/discoverylistener.cpp b/src/server/net/discoverylistener.cpp
index d644259..9586a71 100644
--- a/src/server/net/discoverylistener.cpp
+++ b/src/server/net/discoverylistener.cpp
@@ -30,7 +30,7 @@
  * @brief DiscoveryListener::DiscoveryListener
  */
 DiscoveryListener::DiscoveryListener(QObject *parent)
-		: _socket(this)
+        : QObject(parent), _socket(this)
 {
 	if (!_socket.bind(QHostAddress::AnyIPv4, SERVICE_DISCOVERY_PORT)) {
 		qFatal("Could not bind to service discovery port %d", int(SERVICE_DISCOVERY_PORT));
@@ -128,15 +128,17 @@ void DiscoveryListener::onReadyRead()
 			continue;
 		const quint16 bucket = hash(addr) % SD_PACKET_TABLE_SIZE;
 		if (_packetCounter[bucket] > SPAM_CUTOFF) {
-			qDebug() << "SD: Potential (D)DoS from " << _socket.peerAddress().toString();
+			qDebug() << "SD: Potential (D)DoS from " << addr.toString();
 			// emit some signal and pop up a big warning that someone is flooding/ddosing the PVS SD
 			// ... on the other hand, will the user understand? ;)
 			continue;
 		}
 		++_packetCounter[bucket];
 		_packet.reset();
-		if (_packet.readMessage(data, quint32(size)) != NM_READ_OK)
+		if (_packet.readMessage(data, quint32(size)) != NM_READ_OK) {
+			qDebug() << "Corrupted service discovery message from" << addr.toString();
 			continue;
+		}
 		// Valid packet, process it:
 		const QByteArray iplist(_packet.getFieldBytes(_IPLIST));
 		const QByteArray hash(_packet.getFieldBytes(_HASH));
@@ -146,12 +148,16 @@ void DiscoveryListener::onReadyRead()
 		if (salt1.size() < 16 || salt2.size() < 16)
 			continue; // To make this more secure, you could remember the last X salts used, and ignore new packets using the same
 		// Check if the source IP of the packet matches any of the addresses given in the IP list
-		if (!Network::isAddressInList(QString::fromUtf8(iplist), addr.toString()))
+		if (!Network::isAddressInList(QString::fromUtf8(iplist), addr.toString())) {
+			qDebug() << "SD: Client" << addr.toString() << "did not supply IP in list:" << iplist;
 			continue;
+		}
 		// If so, check if the submitted hash seems valid
 		if (genSha1(&serverApp->sessionNameArray(), &salt1, &iplist) != hash &&
 		        !(serverApp->getCurrentRoom()->clientPositions.contains(addr.toString()))) {
 			// did not match local session name and client is not in same room.
+			qDebug() << "SD: Mismatch, neither session name match, nor client for current room" << serverApp->getCurrentRoom()->tutorIP;
+			qDebug() << "SD: Allowed clients from room:" << serverApp->getCurrentRoom()->clientPositions.keys();
 			continue;
 		}
 
diff --git a/src/server/serverapp/serverapp.cpp b/src/server/serverapp/serverapp.cpp
index 900d3a4..c91ed15 100644
--- a/src/server/serverapp/serverapp.cpp
+++ b/src/server/serverapp/serverapp.cpp
@@ -145,7 +145,7 @@ const Room* ServerApp::getCurrentRoom() const
 	static Room* defaultRoom = nullptr;
 	if (defaultRoom == nullptr) {
 		defaultRoom = new Room(QMap<QString,
-							   QPoint>(), QSize(8, 6), QSize(1, 1), "", "");
+							   QPoint>(), QSize(8, 6), QSize(1, 1), "", "<none>");
 	}
 	return defaultRoom;
 }
-- 
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