X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=KernelLand%2FModules%2FIPStack%2Ftcp.c;fp=KernelLand%2FModules%2FIPStack%2Ftcp.c;h=ac58ec3721c185f485a832040315d7e8e2dd6a6a;hb=3bd7834dc2892fae3a24782a4f150629140574d2;hp=8f16da849410c441773276b07ade4c564080ea45;hpb=2b339e917d778c76b249457bcb66c4fb0007c495;p=tpg%2Facess2.git

diff --git a/KernelLand/Modules/IPStack/tcp.c b/KernelLand/Modules/IPStack/tcp.c
index 8f16da84..ac58ec37 100644
--- a/KernelLand/Modules/IPStack/tcp.c
+++ b/KernelLand/Modules/IPStack/tcp.c
@@ -2,7 +2,7 @@
  * Acess2 IP Stack
  * - TCP Handling
  */
-#define DEBUG	0
+#define DEBUG	1
 #include "ipstack.h"
 #include "ipv4.h"
 #include "ipv6.h"
@@ -52,6 +52,7 @@ size_t	TCP_Client_Write(tVFS_Node *Node, off_t Offset, size_t Length, const void
 void	TCP_Client_Close(tVFS_Node *Node);
 // --- Helpers
  int	WrapBetween(Uint32 Lower, Uint32 Value, Uint32 Higher, Uint32 MaxValue);
+Uint32	GetRelative(Uint32 Base, Uint32 Value);
 
 // === TEMPLATES ===
 tSocketFile	gTCP_ServerFile = {NULL, "tcps", TCP_Server_Init};
@@ -119,7 +120,7 @@ void TCP_int_SendPacket(tInterface *Interface, const void *Dest, tTCPHeader *Hea
 
 	LOG("Sending %i+%i to %s:%i", sizeof(*Header), Length,
 		IPStack_PrintAddress(Interface->Type, Dest),
-		ntohs(Header->RemotePort)
+		ntohs(Header->DestPort)
 		);
 
 	Header->Checksum = 0;
@@ -289,6 +290,7 @@ void TCP_GetPacket(tInterface *Interface, void *Address, int Length, void *Buffe
 		conn->NextSequenceRcv = ntohl( hdr->SequenceNumber ) + 1;
 		conn->HighestSequenceRcvd = conn->NextSequenceRcv;
 		conn->NextSequenceSend = rand();
+		conn->LastACKSequence = ntohl( hdr->SequenceNumber );
 		
 		conn->Node.ImplInt = srv->NextID ++;
 		
@@ -516,7 +518,9 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
 
 			#if 1
 			// - Only send an ACK if we've had a burst
-			if( Connection->NextSequenceRcv > (Uint32)(TCP_DACK_THRESHOLD + Connection->LastACKSequence) )
+			Uint32	bytes_since_last_ack = Connection->NextSequenceRcv - Connection->LastACKSequence;
+			LOG("bytes_since_last_ack = 0x%x", bytes_since_last_ack);
+			if( bytes_since_last_ack > TCP_DACK_THRESHOLD )
 			{
 				TCP_INT_SendACK(Connection, "DACK Burst");
 				// - Extend TCP deferred ACK timer
@@ -529,14 +533,13 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
 			#endif
 		}
 		// Check if the packet is in window
-		else if( WrapBetween(Connection->NextSequenceRcv, sequence_num,
-				Connection->NextSequenceRcv+TCP_WINDOW_SIZE, 0xFFFFFFFF) )
+		else if( sequence_num - Connection->NextSequenceRcv < TCP_WINDOW_SIZE )
 		{
 			Uint8	*dataptr = (Uint8*)Header + (Header->DataOffset>>4)*4;
-			#if CACHE_FUTURE_PACKETS_IN_BYTES
-			Uint32	index;
-			
-			index = sequence_num % TCP_WINDOW_SIZE;
+			Uint32	index = sequence_num % TCP_WINDOW_SIZE;
+			Uint32	max = Connection->NextSequenceRcv % TCP_WINDOW_SIZE;
+			if( !(Connection->FuturePacketValidBytes[index/8] & (1 << (index%8))) )
+				TCP_INT_SendACK(Connection, "Lost packet");
 			for( int i = 0; i < dataLen; i ++ )
 			{
 				Connection->FuturePacketValidBytes[index/8] |= 1 << (index%8);
@@ -544,52 +547,15 @@ void TCP_INT_HandleConnectionPacket(tTCPConnection *Connection, tTCPHeader *Head
 				// Do a wrap increment
 				index ++;
 				if(index == TCP_WINDOW_SIZE)	index = 0;
+				if(index == max)	break;
 			}
-			#else
-			tTCPStoredPacket	*pkt, *tmp, *prev = NULL;
-			
-			// Allocate and fill cached packet
-			pkt = malloc( sizeof(tTCPStoredPacket) + dataLen );
-			pkt->Next = NULL;
-			pkt->Sequence = ntohl(Header->SequenceNumber);
-			pkt->Length = dataLen;
-			memcpy(pkt->Data, dataptr, dataLen);
-			
-			Log_Log("TCP", "We missed a packet, caching",
-				pkt->Sequence, Connection->NextSequenceRcv);
-			
-			// No? Well, let's cache it and look at it later
-			SHORTLOCK( &Connection->lFuturePackets );
-			for(tmp = Connection->FuturePackets;
-				tmp;
-				prev = tmp, tmp = tmp->Next)
-			{
-				if(tmp->Sequence >= pkt->Sequence)	break;
-			}
-			
-			// Add if before first, or sequences don't match 
-			if( !tmp || tmp->Sequence != pkt->Sequence )
-			{
-				if(prev)
-					prev->Next = pkt;
-				else
-					Connection->FuturePackets = pkt;
-				pkt->Next = tmp;
-			}
-			// Replace if larger
-			else if(pkt->Length > tmp->Length)
-			{
-				if(prev)
-					prev->Next = pkt;
-				pkt->Next = tmp->Next;
-				free(tmp);
-			}
-			else
+			Uint32	rel_highest = Connection->HighestSequenceRcvd - Connection->NextSequenceRcv;
+			Uint32	rel_this = index - Connection->NextSequenceRcv;
+			LOG("Updating highest this(0x%x) > highest(%x)", rel_this, rel_highest);
+			if( rel_this > rel_highest )
 			{
-				free(pkt);	// TODO: Find some way to remove this
+				Connection->HighestSequenceRcvd = index;
 			}
-			SHORTREL( &Connection->lFuturePackets );
-			#endif
 		}
 		// Badly out of sequence packet
 		else
@@ -716,17 +682,18 @@ int TCP_INT_AppendRecieved(tTCPConnection *Connection, const void *Data, size_t
  */
 void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 {
-	#if CACHE_FUTURE_PACKETS_IN_BYTES
 	// Calculate length of contiguous bytes
-	 int	length = Connection->HighestSequenceRcvd - Connection->NextSequenceRcv;
+	const int	length = Connection->HighestSequenceRcvd - Connection->NextSequenceRcv;
 	Uint32	index = Connection->NextSequenceRcv % TCP_WINDOW_SIZE;
-	LOG("length=%i, index=%i", length, index);
+	size_t	runlength = length;
+	LOG("length=%i, index=0x%x", length, index);
 	for( int i = 0; i < length; i ++ )
 	{
 		 int	bit = index % 8;
 		Uint8	bitfield_byte = Connection->FuturePacketValidBytes[index / 8];
 		if( (bitfield_byte & (1 << bit)) == 0 ) {
-			length = i;
+			runlength = i;
+			LOG("Hit missing, break");
 			break;
 		}
 
@@ -743,90 +710,51 @@ void TCP_INT_UpdateRecievedFromFuture(tTCPConnection *Connection)
 	}
 	
 	index = Connection->NextSequenceRcv % TCP_WINDOW_SIZE;
+	Connection->NextSequenceRcv += runlength;
 	
 	// Write data to to the ring buffer
-	if( TCP_WINDOW_SIZE - index > length )
+	if( TCP_WINDOW_SIZE - index > runlength )
 	{
 		// Simple case
-		RingBuffer_Write( Connection->RecievedBuffer, Connection->FuturePacketData + index, length );
+		RingBuffer_Write( Connection->RecievedBuffer, Connection->FuturePacketData + index, runlength );
 	}
 	else
 	{
 		 int	endLen = TCP_WINDOW_SIZE - index;
 		// 2-part case
 		RingBuffer_Write( Connection->RecievedBuffer, Connection->FuturePacketData + index, endLen );
-		RingBuffer_Write( Connection->RecievedBuffer, Connection->FuturePacketData, endLen - length );
+		RingBuffer_Write( Connection->RecievedBuffer, Connection->FuturePacketData, endLen - runlength );
 	}
 	
 	// Mark (now saved) bytes as invalid
 	// - Align index
-	while(index % 8 && length > 0)
+	while(index % 8 && runlength > 0)
 	{
 		Connection->FuturePacketData[index] = 0;
 		Connection->FuturePacketValidBytes[index/8] &= ~(1 << (index%8));
 		index ++;
 		if(index > TCP_WINDOW_SIZE)
 			index -= TCP_WINDOW_SIZE;
-		length --;
+		runlength --;
 	}
-	while( length > 7 )
+	while( runlength > 7 )
 	{
 		Connection->FuturePacketData[index] = 0;
 		Connection->FuturePacketValidBytes[index/8] = 0;
-		length -= 8;
+		runlength -= 8;
 		index += 8;
 		if(index > TCP_WINDOW_SIZE)
 			index -= TCP_WINDOW_SIZE;
 	}
-	while(length)
+	while( runlength > 0)
 	{
 		Connection->FuturePacketData[index] = 0;
 		Connection->FuturePacketData[index/8] &= ~(1 << (index%8));
 		index ++;
 		if(index > TCP_WINDOW_SIZE)
 			index -= TCP_WINDOW_SIZE;
-		length --;
-	}
-	
-	#else
-	tTCPStoredPacket	*pkt;
-	for(;;)
-	{
-		SHORTLOCK( &Connection->lFuturePackets );
-		
-		// Clear out duplicates from cache
-		// - If a packet has just been recieved, and it is expected, then
-		//   (since NextSequenceRcv = rcvd->Sequence + rcvd->Length) all
-		//   packets in cache that are smaller than the next expected
-		//   are now defunct.
-		pkt = Connection->FuturePackets;
-		while(pkt && pkt->Sequence < Connection->NextSequenceRcv)
-		{
-			tTCPStoredPacket	*next = pkt->Next;
-			free(pkt);
-			pkt = next;
-		}
-		
-		// If there's no packets left in cache, stop looking
-		if(!pkt || pkt->Sequence > Connection->NextSequenceRcv) {
-			SHORTREL( &Connection->lFuturePackets );
-			return;
-		}
-		
-		// Delete packet from future list
-		Connection->FuturePackets = pkt->Next;
-		
-		// Release list
-		SHORTREL( &Connection->lFuturePackets );
-		
-		// Looks like we found one
-		TCP_INT_AppendRecieved(Connection, pkt->Data, pkt->Length);
-		if( Connection->HighestSequenceRcvd == Connection->NextSequenceRcv )
-			Connection->HighestSequenceRcvd += pkt->Length;
-		Connection->NextSequenceRcv += pkt->Length;
-		free(pkt);
+		runlength --;
 	}
-	#endif
 }
 
 void TCP_int_SendDelayedACK(void *ConnPtr)
@@ -1259,6 +1187,8 @@ void TCP_INT_SendDataPacket(tTCPConnection *Connection, size_t Length, const voi
 
 	// - Stop Delayed ACK timer (as this data packet ACKs)
 	Time_RemoveTimer(Connection->DeferredACKTimer);
+
+	// TODO: Don't exceed window size
 	
 	packet->SourcePort = htons(Connection->LocalPort);
 	packet->DestPort = htons(Connection->RemotePort);
@@ -1534,3 +1464,10 @@ int WrapBetween(Uint32 Lower, Uint32 Value, Uint32 Higher, Uint32 MaxValue)
 	
 	return 0;
 }
+Uint32 GetRelative(Uint32 Base, Uint32 Value)
+{
+	if( Value < Base )
+		return Value - Base + 0xFFFFFFFF;
+	else
+		return Value - Base;
+}