Merge pull request #4 from Learath2/zcatchspoof

Antispoof

1 files changed, 28 insertions, 8 deletions

diff --git a/src/engine/shared/network.cpp b/src/engine/shared/network.cpp
index ada4b18a..eb1a51dc 100644
--- a/src/engine/shared/network.cpp
+++ b/src/engine/shared/network.cpp
@@ -58,10 +58,13 @@ int CNetRecvUnpacker::FetchChunk(CNetChunk *pChunk)
 		// handle sequence stuff
 		if(m_pConnection && (Header.m_Flags&NET_CHUNKFLAG_VITAL))
 		{
-			if(Header.m_Sequence == (m_pConnection->m_Ack+1)%NET_MAX_SEQUENCE)
+			// anti spoof: ignore unknown sequence
+			if(Header.m_Sequence == (m_pConnection->m_Ack+1)%NET_MAX_SEQUENCE || m_pConnection->m_UnknownSeq)
 			{
+				m_pConnection->m_UnknownSeq = false;
+
 				// in sequence
-				m_pConnection->m_Ack = (m_pConnection->m_Ack+1)%NET_MAX_SEQUENCE;
+				m_pConnection->m_Ack = Header.m_Sequence;
 			}
 			else
 			{
@@ -80,7 +83,7 @@ int CNetRecvUnpacker::FetchChunk(CNetChunk *pChunk)
 		// fill in the info
 		pChunk->m_ClientID = m_ClientID;
 		pChunk->m_Address = m_Addr;
-		pChunk->m_Flags = 0;
+		pChunk->m_Flags = Header.m_Flags;
 		pChunk->m_DataSize = Header.m_Size;
 		pChunk->m_pData = pData;
 		return 1;
@@ -101,7 +104,7 @@ void CNetBase::SendPacketConnless(NETSOCKET Socket, NETADDR *pAddr, const void *
 	net_udp_send(Socket, pAddr, aBuffer, 6+DataSize);
 }
 
-void CNetBase::SendPacket(NETSOCKET Socket, NETADDR *pAddr, CNetPacketConstruct *pPacket)
+void CNetBase::SendPacket(NETSOCKET Socket, NETADDR *pAddr, CNetPacketConstruct *pPacket, SECURITY_TOKEN SecurityToken)
 {
 	unsigned char aBuffer[NET_MAX_PACKETSIZE];
 	int CompressedSize = -1;
@@ -117,6 +120,14 @@ void CNetBase::SendPacket(NETSOCKET Socket, NETADDR *pAddr, CNetPacketConstruct
 		io_flush(ms_DataLogSent);
 	}
 
+	if (SecurityToken != NET_SECURITY_TOKEN_UNSUPPORTED)
+	{
+		// append security token
+		// if SecurityToken is NET_SECURITY_TOKEN_UNKNOWN we will still append it hoping to negotiate it
+		mem_copy(&pPacket->m_aChunkData[pPacket->m_DataSize], &SecurityToken, sizeof(SecurityToken));
+		pPacket->m_DataSize += sizeof(SecurityToken);
+	}
+
 	// compress
 	CompressedSize = ms_Huffman.Compress(pPacket->m_aChunkData, pPacket->m_DataSize, &aBuffer[3], NET_MAX_PACKETSIZE-4);
 
@@ -161,7 +172,8 @@ int CNetBase::UnpackPacket(unsigned char *pBuffer, int Size, CNetPacketConstruct
 	// check the size
 	if(Size < NET_PACKETHEADERSIZE || Size > NET_MAX_PACKETSIZE)
 	{
-		dbg_msg("", "packet too small, %d", Size);
+		if(g_Config.m_Debug)
+			dbg_msg("", "packet too small, %d", Size);
 		return -1;
 	}
 
@@ -185,7 +197,8 @@ int CNetBase::UnpackPacket(unsigned char *pBuffer, int Size, CNetPacketConstruct
 	{
 		if(Size < 6)
 		{
-			dbg_msg("", "connection less packet too small, %d", Size);
+			if(g_Config.m_Debug)
+				dbg_msg("", "connection less packet too small, %d", Size);
 			return -1;
 		}
 
@@ -198,7 +211,14 @@ int CNetBase::UnpackPacket(unsigned char *pBuffer, int Size, CNetPacketConstruct
 	else
 	{
 		if(pPacket->m_Flags&NET_PACKETFLAG_COMPRESSION)
+		{
+			// Don't allow compressed control packets.
+			if(pPacket->m_Flags&NET_PACKETFLAG_CONTROL)
+			{
+				return -1;
+			}
 			pPacket->m_DataSize = ms_Huffman.Decompress(&pBuffer[3], pPacket->m_DataSize, pPacket->m_aChunkData, sizeof(pPacket->m_aChunkData));
+		}
 		else
 			mem_copy(pPacket->m_aChunkData, &pBuffer[3], pPacket->m_DataSize);
 	}
@@ -226,7 +246,7 @@ int CNetBase::UnpackPacket(unsigned char *pBuffer, int Size, CNetPacketConstruct
 }
 
 
-void CNetBase::SendControlMsg(NETSOCKET Socket, NETADDR *pAddr, int Ack, int ControlMsg, const void *pExtra, int ExtraSize)
+void CNetBase::SendControlMsg(NETSOCKET Socket, NETADDR *pAddr, int Ack, int ControlMsg, const void *pExtra, int ExtraSize, SECURITY_TOKEN SecurityToken)
 {
 	CNetPacketConstruct Construct;
 	Construct.m_Flags = NET_PACKETFLAG_CONTROL;
@@ -237,7 +257,7 @@ void CNetBase::SendControlMsg(NETSOCKET Socket, NETADDR *pAddr, int Ack, int Con
 	mem_copy(&Construct.m_aChunkData[1], pExtra, ExtraSize);
 
 	// send the control message
-	CNetBase::SendPacket(Socket, pAddr, &Construct);
+	CNetBase::SendPacket(Socket, pAddr, &Construct, SecurityToken);
 }