proxy: Fix handling of in drdynvc DATA_FIRST_PDU in proxy

During tests I sometimes received DATA_FIRST_PDUs that were not part of a fragmented message but contained a complete PDU. The documentation is not quite clear about if this is a possible scenario or a protocol violation. However in the description of the Data field it says: If the sum of the DVC header size and the value specified by the Length field is less than 1600 bytes, then the actual data length equals the value specified by the Length field. This hints that DATA_FIRST_PDU might also contain complete Data and does not necessarily mean to be the first part of a fragmented PDU.
gcracker · Sep 29, 2022 · e4f476f · e4f476f
1 parent b448104
commit e4f476f
Showing 1 changed file with 7 additions and 7 deletions.
diff --git a/server/proxy/channels/pf_channel_drdynvc.c b/server/proxy/channels/pf_channel_drdynvc.c
@@ -406,13 +406,6 @@ static PfChannelResult DynvcTrackerPeekFn(ChannelStateTracker* tracker, BOOL fir
 				    trackerState->CurrentDataReceived, trackerState->currentDataLength);
 				return PF_CHANNEL_RESULT_ERROR;
 			}
-
-			if (trackerState->CurrentDataReceived == trackerState->currentDataLength)
-			{
-				trackerState->currentDataLength = 0;
-				trackerState->CurrentDataFragments = 0;
-				trackerState->CurrentDataReceived = 0;
-			}
 		}
 		else
 		{
@@ -421,6 +414,13 @@ static PfChannelResult DynvcTrackerPeekFn(ChannelStateTracker* tracker, BOOL fir
 		}
 	}
 
+	if (trackerState->CurrentDataReceived == trackerState->currentDataLength)
+	{
+		trackerState->currentDataLength = 0;
+		trackerState->CurrentDataFragments = 0;
+		trackerState->CurrentDataReceived = 0;
+	}
+
 	switch (dynChannel->channelMode)
 	{
 		case PF_UTILS_CHANNEL_PASSTHROUGH: