Limit the avatar requests by the server - clients may only upload one avatar within a certain time. This is checked by IP address, so two players within the same NAT system might have to wait for a few seconds.

src/net/common/connectdata.cpp

@@ -20,7 +20,7 @@
 #include <net/connectdata.h>
 
 ConnectData::ConnectData()
-: m_sockfd(INVALID_SOCKET)
+: m_sockfd(INVALID_SOCKET), m_peerAddrSize(sizeof(m_peerAddr))
 {
 }
 

src/net/common/serveracceptthread.cpp

@@ -182,17 +182,31 @@ ServerAcceptThread::AcceptLoop()
 		{
 			throw ServerException(__FILE__, __LINE__, ERR_SOCK_CREATION_FAILED, SOCKET_ERRNO());
 		}
-		// Optional calls - don't check return value.
-		// Enable keepalive - won't be of much use but better than nothing.
-		int keepalive = 1;
-		setsockopt(tmpData->GetSocket(), SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive, sizeof(keepalive));
 
-#ifdef SO_NOSIGPIPE
-		int nosigpipe = 1;
-		setsockopt(tmpData->GetSocket(), SOL_SOCKET, SO_NOSIGPIPE, (char *)&nosigpipe, sizeof(nosigpipe));
-#endif
+		// Retrieve peer address.
+		int addrLen = tmpData->GetPeerAddrSize();
+		if (getpeername(tmpData->GetSocket(), tmpData->GetPeerAddr(), &addrLen) != 0)
+		{
+			// Something went wrong with the connection, just continue (socket will be closed).
+			LOG_ERROR("getpeername() failed: " << SOCKET_ERRNO());
+		}
+		else
+		{
+			// Set the size of the peer address.
+			tmpData->SetPeerAddrSize(addrLen);
 
-		GetLobbyThread().AddConnection(tmpData);
+			// Optional calls - don't check return value.
+			// Enable keepalive - won't be of much use but better than nothing.
+			int keepalive = 1;
+			setsockopt(tmpData->GetSocket(), SOL_SOCKET, SO_KEEPALIVE, (char *)&keepalive, sizeof(keepalive));
+
+	#ifdef SO_NOSIGPIPE
+			int nosigpipe = 1;
+			setsockopt(tmpData->GetSocket(), SOL_SOCKET, SO_NOSIGPIPE, (char *)&nosigpipe, sizeof(nosigpipe));
+	#endif
+
+			GetLobbyThread().AddConnection(tmpData);
+		}
 	}
 }
 

src/net/common/serverlobbythread.cpp

@@ -38,6 +38,7 @@
 #define SERVER_CACHE_CLEANUP_INTERVAL_SEC	86400	// 1 day
 #define SERVER_SAVE_STATISTICS_INTERVAL_SEC	60
 #define SERVER_INIT_SESSION_TIMEOUT_SEC		20
+#define SERVER_INIT_AVATAR_CLIENT_LOCK_SEC	30      // Forbid a client to send an additional avatar.
 
 #define SERVER_STATISTICS_FILE_NAME				"server_statistics.log"
 #define SERVER_STATISTICS_STR_TOTAL_PLAYERS		"TotalNumPlayersLoggedIn"
@@ -313,6 +314,8 @@ ServerLobbyThread::Main()
 			RemoveGameLoop();
 			// Kick players.
 			KickPlayerLoop();
+			// Update avatar limitation lock.
+			UpdateAvatarClientTimerLoop();
 			// Cleanup cache.
 			CleanupAvatarCache();
 			// Save statistics if needed.
@@ -442,10 +445,25 @@ ServerLobbyThread::HandleNetPacketInit(SessionWrapper session, const NetPacketIn
 	m_sessionManager.SetSessionPlayerData(session.sessionData->GetId(), tmpPlayerData);
 	session.playerData = tmpPlayerData;
 
-	if (initData.showAvatar && !initData.avatar.IsZero() && !GetAvatarManager().HasAvatar(initData.avatar))
-		RequestPlayerAvatar(session);
+	if (initData.showAvatar
+		&& !initData.avatar.IsZero()
+		&& !GetAvatarManager().HasAvatar(initData.avatar))
+	{
+		bool avatarRecentlyRequested = false;
+		{
+			boost::mutex::scoped_lock lock(m_timerAvatarClientAddressMapMutex);
+			if (m_timerAvatarClientAddressMap.find(session.sessionData->GetClientAddr()) != m_timerAvatarClientAddressMap.end())
+				avatarRecentlyRequested = true;
+		}
+		if (avatarRecentlyRequested)
+			SessionError(session, ERR_NET_INVALID_AVATAR_FILE);
+		else
+			RequestPlayerAvatar(session);
+	}
 	else
+	{
 		EstablishSession(session);
+	}
 }
 
 void
@@ -698,6 +716,11 @@ ServerLobbyThread::RequestPlayerAvatar(SessionWrapper session)
 {
 	if (!session.playerData.get())
 		throw ServerException(__FILE__, __LINE__, ERR_NET_INVALID_SESSION, 0);
+	// Accept no more new avatars from that client for a certain time.
+	{
+		boost::mutex::scoped_lock lock(m_timerAvatarClientAddressMapMutex);
+		m_timerAvatarClientAddressMap[session.sessionData->GetClientAddr()] = boost::timers::portable::microsec_timer();
+	}
 	// Ask the client to send its avatar.
 	boost::shared_ptr<NetPacket> retrieveAvatar(new NetPacketRetrieveAvatar);
 	NetPacketRetrieveAvatar::Data retrieveAvatarData;
@@ -745,13 +768,13 @@ void
 ServerLobbyThread::CloseSessionLoop()
 {
 	boost::mutex::scoped_lock lock(m_initTimerSessionMapMutex);
-	InitTimerSessionMap::iterator i = m_initTimerSessionMap.begin();
-	InitTimerSessionMap::iterator end = m_initTimerSessionMap.end();
+	TimerSessionMap::iterator i = m_initTimerSessionMap.begin();
+	TimerSessionMap::iterator end = m_initTimerSessionMap.end();
 
 	// Remove sessions if they do not initialize within a certain period.
 	while (i != end)
 	{
-		InitTimerSessionMap::iterator next = i;
+		TimerSessionMap::iterator next = i;
 		++next;
 		if (i->second.elapsed().total_seconds() > SERVER_INIT_SESSION_TIMEOUT_SEC)
 		{
@@ -803,6 +826,24 @@ ServerLobbyThread::KickPlayerLoop()
 	m_kickPlayerList.clear();
 }
 
+void
+ServerLobbyThread::UpdateAvatarClientTimerLoop()
+{
+	boost::mutex::scoped_lock lock(m_timerAvatarClientAddressMapMutex);
+
+	TimerClientAddressMap::iterator i = m_timerAvatarClientAddressMap.begin();
+	TimerClientAddressMap::iterator end = m_timerAvatarClientAddressMap.end();
+
+	while (i != end)
+	{
+		TimerClientAddressMap::iterator next = i;
+		++next;
+		if (i->second.elapsed().total_seconds() > SERVER_INIT_AVATAR_CLIENT_LOCK_SEC)
+			m_timerAvatarClientAddressMap.erase(i);
+		i = next;
+	}
+}
+
 void
 ServerLobbyThread::CleanupAvatarCache()
 {
@@ -907,6 +948,14 @@ ServerLobbyThread::HandleNewConnection(boost::shared_ptr<ConnectData> connData)
 
 	if (m_sessionManager.GetRawSessionCount() <= SERVER_MAX_NUM_SESSIONS)
 	{
+		char tmpAddress[MAX_ADDR_STRING_LEN];
+		// Only consider address, set port to zero.
+		if (socket_set_port(0, connData->GetPeerAddr()->sa_family, connData->GetPeerAddr(), connData->GetPeerAddrSize())
+			&& socket_addr_to_string(connData->GetPeerAddr(), connData->GetPeerAddrSize(), connData->GetPeerAddr()->sa_family, tmpAddress, sizeof(tmpAddress)))
+		{
+			tmpAddress[sizeof(tmpAddress) - 1] = 0; // paranoia
+			sessionData->SetClientAddr(tmpAddress);
+		}
 		boost::mutex::scoped_lock lock(m_initTimerSessionMapMutex);
 		m_initTimerSessionMap[sessionData->GetId()] = boost::timers::portable::microsec_timer();
 	}

src/net/connectdata.h

@@ -36,8 +36,16 @@ public:
 
 	SOCKET ReleaseSocket();
 
+	struct sockaddr *GetPeerAddr() {return (sockaddr *)&m_peerAddr;}
+	int GetPeerAddrSize() const {return m_peerAddrSize;}
+
+	void SetPeerAddrSize(int addrSize) {m_peerAddrSize = addrSize;}
+
 private:
-	SOCKET				m_sockfd;
+	SOCKET					m_sockfd;
+
+	struct sockaddr_storage	m_peerAddr;
+	int						m_peerAddrSize;
 };
 
 #endif

src/net/linux/socket_helper.cpp

@@ -34,6 +34,12 @@ socket_string_to_addr(const char *str, int addrFamily, struct sockaddr *addr, in
 		return false;
 }
 
+bool
+socket_addr_to_string(struct sockaddr *addr, int /*addrLen*/, int addrFamily, char *str, int strLen)
+{
+	return (inet_ntop(addrFamily, addr, str, strLen) != NULL);
+}
+
 bool
 socket_resolve(const char *str, const char *port, int addrFamily, int sockType, int protocol, struct sockaddr *addr, int addrLen)
 {

src/net/serverlobbythread.h

@@ -90,8 +90,9 @@ protected:
 	typedef std::deque<boost::shared_ptr<ConnectData> > ConnectQueue;
 	typedef std::deque<SessionWrapper> SessionQueue;
 	typedef std::list<SessionWrapper> SessionList;
-	typedef std::map<SessionId, boost::timers::portable::microsec_timer> InitTimerSessionMap;
+	typedef std::map<SessionId, boost::timers::portable::microsec_timer> TimerSessionMap;
 	typedef std::map<unsigned, boost::shared_ptr<ServerGameThread> > GameMap;
+	typedef std::map<std::string, boost::timers::portable::microsec_timer> TimerClientAddressMap;
 	typedef std::list<unsigned> RemoveGameList;
 	typedef std::list<boost::shared_ptr<SenderThread> > SenderThreadList;
 
@@ -115,6 +116,7 @@ protected:
 	void CloseSessionLoop();
 	void RemoveGameLoop();
 	void KickPlayerLoop();
+	void UpdateAvatarClientTimerLoop();
 	void CleanupAvatarCache();
 
 	void InternalAddGame(boost::shared_ptr<ServerGameThread> game);
@@ -164,9 +166,12 @@ private:
 	SessionManager m_sessionManager;
 	SessionManager m_gameSessionManager;
 
-	InitTimerSessionMap m_initTimerSessionMap;
+	TimerSessionMap m_initTimerSessionMap;
 	mutable boost::mutex m_initTimerSessionMapMutex;
 
+	TimerClientAddressMap m_timerAvatarClientAddressMap;
+	mutable boost::mutex m_timerAvatarClientAddressMapMutex;
+
 	RemoveGameList m_removeGameList;
 	mutable boost::mutex m_removeGameListMutex;
 
@@ -176,6 +181,7 @@ private:
 	PlayerDataMap m_computerPlayers;
 	mutable boost::mutex m_computerPlayersMutex;
 
+
 	GameMap m_gameMap;
 
 	boost::shared_ptr<ReceiverHelper> m_receiver;

src/net/socket_helper.h

@@ -88,6 +88,8 @@ typedef unsigned char					u_char;
 	#define SOCKET_IPPROTO_SCTP			0
 #endif
 
+#define MAX_ADDR_STRING_LEN 256
+
 // All char *s are assumed to be UTF-8.
 
 /**
@@ -96,6 +98,11 @@ typedef unsigned char					u_char;
  */
 bool socket_string_to_addr(const char *str, int addrFamily, struct sockaddr *addr, int addrLen);
 
+/**
+ * Convert a numeric address to an address string.
+ */
+bool socket_addr_to_string(struct sockaddr *addr, int addrLen, int addrFamily, char *str, int strLen);
+
 /**
  * Resolve a name to a numeric address.
  * str is assumed to be UTF-8 encoded.

src/net/win32/socket_helper.cpp

@@ -73,6 +73,15 @@ socket_string_to_addr(const char *str, int addrFamily, struct sockaddr * addr, i
 	return retVal;
 }
 
+bool
+socket_addr_to_string(struct sockaddr *addr, int addrLen, int addrFamily, char *str, int strLen)
+{
+	bool retVal = false;
+	retVal = (WSAAddressToStringA(addr, addrLen, NULL, str, (DWORD *)&strLen) != SOCKET_ERROR);
+
+	return retVal;
+}
+
 bool
 socket_resolve(const char *str, const char *port, int addrFamily, int sockType, int protocol, struct sockaddr *addr, int addrLen)
 {