* Added ECN support

bwmd/autoclass.c

@@ -161,11 +161,13 @@ static unsigned char autoClassify_tos(struct ip_packet_t *ip_packet, unsigned ch
 {
 	unsigned char prio = 0;
 	// Get type of  service
-	unsigned char tos = IPTOS_TOS(ip_packet->tos);
+//	unsigned char ecn = AUTOCLASS_TOS_ECN_MASK(ip_packet->tos);
+	unsigned char tos = AUTOCLASS_TOS_MASK(ip_packet->tos);
+//	unsigned char prec = AUTOCLASS_TOS_PREC_MASK(ip_packet->tos);
 
 
 	// Decide what we doing...
-	if (tos == IPTOS_LOWDELAY)	
+	if (tos == AUTOCLASS_TOS_LOWDELAY)	
 	{
 /*
  * 1. LOW DELAY
@@ -174,7 +176,7 @@ static unsigned char autoClassify_tos(struct ip_packet_t *ip_packet, unsigned ch
  */
 		prio = 10;
 	}
-	else if (tos == IPTOS_THROUGHPUT)
+	else if (tos == AUTOCLASS_TOS_THROUGHPUT)
 	{
 /*
  * 2. THROUGHPUT
@@ -182,22 +184,13 @@ static unsigned char autoClassify_tos(struct ip_packet_t *ip_packet, unsigned ch
  *  - low drop probability
  */
 	}
-	else if (tos == IPTOS_RELIABILITY)
+	else if (tos == AUTOCLASS_TOS_RELIABILITY)
 	{
 /*
  * 3. RELIABILITY
  *  - low drop probability
  */
 	}
-	else if (tos == IPTOS_MINCOST)
-	{
-/*
- * 4. MIN COST
- *  - PRIO 90
- *  - high drop probability
- */
-		prio = 90;
-	}
 
 	return prio;
 }

bwmd/flow.c

@@ -365,7 +365,18 @@ static unsigned int processPktQueue(struct runnerData_t *runnerData, struct pktQ
 		{
 			// Re-inject packet for processing, check if it was ok...
 			g_mutex_lock(runnerData->IPQLock);
-			status = ipq_set_verdict(runnerData->IPQHandle, PKT_ID(packet), NF_ACCEPT, 0, NULL);
+			
+			// Check if our packet was changed
+			if (packet->changed)
+			{
+				struct ip_packet_t *ip_packet = (struct ip_packet_t *) packet->payload->payload;
+
+				// Send packet back modified
+				status = ipq_set_verdict(runnerData->IPQHandle, PKT_ID(packet), NF_ACCEPT, ip_packet->tot_len, (unsigned char *) ip_packet);
+			}
+			else
+				status = ipq_set_verdict(runnerData->IPQHandle, PKT_ID(packet), NF_ACCEPT, 0, NULL);
+
 			g_mutex_unlock(runnerData->IPQLock);
 			if (status < 0)
 			{

bwmd/ipq.c

@@ -92,6 +92,7 @@ static int queuePacket(struct runnerData_t *runnerData, unsigned long int nfmark
 	int status;
 	int result;
 	int drop = 0;
+	struct ip_packet_t *ip_packet = (struct ip_packet_t *) packet->payload->payload;
 
 
 	// Our find functions
@@ -138,15 +139,8 @@ static int queuePacket(struct runnerData_t *runnerData, unsigned long int nfmark
 	// Now lets see if we don't have a queue... this means AUTO!
 	if (!foundQueue)
 	{
-		struct ip_packet_t *ip_packet = (struct ip_packet_t *) packet->payload->payload;
 		unsigned char prio = 0;
 
-/*		
-		fprintf(stderr,"auto packet queue -> protocol = %i, src = %i.%i.%i.%i, dest = %i.%i.%i.%i, tos = 0x%x\n", ip_packet->protocol, 
-				ip_packet->u_saddr.addr.a, ip_packet->u_saddr.addr.b, ip_packet->u_saddr.addr.c, ip_packet->u_saddr.addr.d, 
-				ip_packet->u_daddr.addr.a, ip_packet->u_daddr.addr.b, ip_packet->u_daddr.addr.c, ip_packet->u_daddr.addr.d, 
-				IPTOS_PREC(ip_packet->tos));
-*/
 		
 		prio = autoClassify(ip_packet,foundFlow->prioClassifier);
 			
@@ -191,8 +185,24 @@ static int queuePacket(struct runnerData_t *runnerData, unsigned long int nfmark
 			prob = avgProb + curProb;
 			// Check if we should drop packet
 			drop = drand < prob;
-		}
+		
+			// If queue is 10% full, set CE bit if we ECN capable
+			if (!drop && (avgQueueSize / curQueueSize) > 0.10)
+			{
+				unsigned char ecn = AUTOCLASS_TOS_ECN_MASK(ip_packet->tos);
+
 
+				// We are ECN capable
+				if (ecn < 3)
+				{
+					// Set CE codepoint to communicate congestion
+					ip_packet->tos |= AUTOCLASS_TOS_ECN_CE;
+					// Tell flowRunner we modified the packet
+					packet->changed = 1;
+				}
+			}
+		}
+		
 	}
 	
 	// Check if we must pass the packet
@@ -327,6 +337,9 @@ void *IPQRunner(void *data)
 				// Copy packet
 				memcpy(packet->payload,m,pkt_len);
 
+				// Set packet as not changed
+				packet->changed = 0;
+				
 				// Queue the packet...
 				status = queuePacket(runnerData,packet->payload->mark,packet);
 				if (status < 0)

include/autoclass.h

@@ -35,6 +35,28 @@
 #define AUTOCLASS_TOS	2
 
 
+// Type of Service / DSCP / ECN ... etc
+#define AUTOCLASS_TOS_ECN_MASK(tos)		((tos) & 0x03)  // Mask of all ECN bits
+#define AUTOCLASS_TOS_ECN_ECT0			0x01
+#define AUTOCLASS_TOS_ECN_ECT1			0x02
+#define AUTOCLASS_TOS_ECN_CE			0x03
+
+#define AUTOCLASS_TOS_MASK(tos)			((tos) & 0x1c)  // Mask of all TOS bits
+#define AUTOCLASS_TOS_RELIABILITY		0x04  // High Reliability
+#define AUTOCLASS_TOS_THROUGHPUT		0x08  // High Throughput
+#define AUTOCLASS_TOS_LOWDELAY			0x10  // Low Delay
+
+#define AUTOCLASS_TOS_PREC_MASK(tos)	((tos) & 0xe0)  // Mask of all PREC bits
+#define AUTOCLASS_TOS_PREC_ROUTINE		0x00  // Routine
+#define AUTOCLASS_TOS_PREC_PRIORITY		0x20  // Priority
+#define AUTOCLASS_TOS_PREC_IMMEDIATE	0x40  // Immediate
+#define AUTOCLASS_TOS_PREC_FLASH		0x60  // Flash
+#define AUTOCLASS_TOS_PREC_FLASH_OVERRIDE 0x80  // Flash Override
+#define AUTOCLASS_TOS_PREC_CRITIC_ECP	0xa0  // Critic/ECP
+#define AUTOCLASS_TOS_PREC_INTERNETWORK_CONTROL 0xc0  // Internetwork control
+#define AUTOCLASS_TOS_PREC_NETWORK_CONTROL 0xe0  // Network control
+
+
 // Auto classify packet and return priority (1 - best, 100 - worst)
 unsigned char autoClassify(struct ip_packet_t *ip_packet, unsigned char prioClassifier);
 

include/common.h

@@ -81,9 +81,11 @@ struct flowData_t
 };
 
 
+// This is used in the queueing and is the item used in the queue
 struct packet_t
 {
 	ipq_packet_msg_t *payload;
+	unsigned char changed;
 };
 
 

include/flow.h

@@ -176,10 +176,12 @@ void updateGroups(
 		int pktBursted);
 
 
-// Flow runner thread
-void *flowRunner(void *data);
+// Message log facility
+void logMessage(int priority, const char *fmt, ...);
 
 
+// Flow runner thread
+void *flowRunner(void *data);
 
 
 // Check if we will exceed flow queuing limits
@@ -189,7 +191,5 @@ static inline int will_exceed_flow_queue(struct flow_t *flow, unsigned int pktSi
 			(flow->curQueueSize + pktSize >= flow->maxQueueSize && flow->maxQueueSize != 0));
 }
 
-extern void logMessage(int priority, const char *fmt, ...);
-
 #endif