Record counts of packets with unknown L3/L4 numbers

Previously, we recorded a single aggregated count. These per-protocol counts
can help us debug field issues when frames are dropped for this reason.

PiperOrigin-RevId: 405913911

3 files changed, 57 insertions, 15 deletions

diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go
index e251e3b24..b9b5c35c8 100644
--- a/pkg/tcpip/stack/nic.go
+++ b/pkg/tcpip/stack/nic.go
@@ -727,7 +727,7 @@ func (n *nic) DeliverNetworkPacket(remote, local tcpip.LinkAddress, protocol tcp
 
 	networkEndpoint, ok := n.networkEndpoints[protocol]
 	if !ok {
-		n.stats.unknownL3ProtocolRcvdPackets.Increment()
+		n.stats.unknownL3ProtocolRcvdPacketCounts.Increment(uint64(protocol))
 		return
 	}
 
@@ -827,7 +827,7 @@ func (n *nic) deliverOutboundPacket(remote tcpip.LinkAddress, pkt *PacketBuffer)
 func (n *nic) DeliverTransportPacket(protocol tcpip.TransportProtocolNumber, pkt *PacketBuffer) TransportPacketDisposition {
 	state, ok := n.stack.transportProtocols[protocol]
 	if !ok {
-		n.stats.unknownL4ProtocolRcvdPackets.Increment()
+		n.stats.unknownL4ProtocolRcvdPacketCounts.Increment(uint64(protocol))
 		return TransportPacketProtocolUnreachable
 	}
 
diff --git a/pkg/tcpip/stack/nic_stats.go b/pkg/tcpip/stack/nic_stats.go
index 1773d5e8d..89aa95131 100644
--- a/pkg/tcpip/stack/nic_stats.go
+++ b/pkg/tcpip/stack/nic_stats.go
@@ -35,7 +35,7 @@ func (m *multiCounterNICPacketStats) init(a, b *tcpip.NICPacketStats) {
 	m.bytes.Init(a.Bytes, b.Bytes)
 }
 
-// LINT.ThenChange(../../tcpip.go:NICPacketStats)
+// LINT.ThenChange(../tcpip.go:NICPacketStats)
 
 // LINT.IfChange(multiCounterNICNeighborStats)
 
@@ -47,23 +47,23 @@ func (m *multiCounterNICNeighborStats) init(a, b *tcpip.NICNeighborStats) {
 	m.unreachableEntryLookups.Init(a.UnreachableEntryLookups, b.UnreachableEntryLookups)
 }
 
-// LINT.ThenChange(../../tcpip.go:NICNeighborStats)
+// LINT.ThenChange(../tcpip.go:NICNeighborStats)
 
 // LINT.IfChange(multiCounterNICStats)
 
 type multiCounterNICStats struct {
-	unknownL3ProtocolRcvdPackets tcpip.MultiCounterStat
-	unknownL4ProtocolRcvdPackets tcpip.MultiCounterStat
-	malformedL4RcvdPackets       tcpip.MultiCounterStat
-	tx                           multiCounterNICPacketStats
-	rx                           multiCounterNICPacketStats
-	disabledRx                   multiCounterNICPacketStats
-	neighbor                     multiCounterNICNeighborStats
+	unknownL3ProtocolRcvdPacketCounts tcpip.MultiIntegralStatCounterMap
+	unknownL4ProtocolRcvdPacketCounts tcpip.MultiIntegralStatCounterMap
+	malformedL4RcvdPackets            tcpip.MultiCounterStat
+	tx                                multiCounterNICPacketStats
+	rx                                multiCounterNICPacketStats
+	disabledRx                        multiCounterNICPacketStats
+	neighbor                          multiCounterNICNeighborStats
 }
 
 func (m *multiCounterNICStats) init(a, b *tcpip.NICStats) {
-	m.unknownL3ProtocolRcvdPackets.Init(a.UnknownL3ProtocolRcvdPackets, b.UnknownL3ProtocolRcvdPackets)
-	m.unknownL4ProtocolRcvdPackets.Init(a.UnknownL4ProtocolRcvdPackets, b.UnknownL4ProtocolRcvdPackets)
+	m.unknownL3ProtocolRcvdPacketCounts.Init(a.UnknownL3ProtocolRcvdPacketCounts, b.UnknownL3ProtocolRcvdPacketCounts)
+	m.unknownL4ProtocolRcvdPacketCounts.Init(a.UnknownL4ProtocolRcvdPacketCounts, b.UnknownL4ProtocolRcvdPacketCounts)
 	m.malformedL4RcvdPackets.Init(a.MalformedL4RcvdPackets, b.MalformedL4RcvdPackets)
 	m.tx.init(&a.Tx, &b.Tx)
 	m.rx.init(&a.Rx, &b.Rx)
@@ -71,4 +71,4 @@ func (m *multiCounterNICStats) init(a, b *tcpip.NICStats) {
 	m.neighbor.init(&a.Neighbor, &b.Neighbor)
 }
 
-// LINT.ThenChange(../../tcpip.go:NICStats)
+// LINT.ThenChange(../tcpip.go:NICStats)
diff --git a/pkg/tcpip/stack/nic_test.go b/pkg/tcpip/stack/nic_test.go
index c8ad93f29..88ca9b076 100644
--- a/pkg/tcpip/stack/nic_test.go
+++ b/pkg/tcpip/stack/nic_test.go
@@ -206,6 +206,45 @@ func TestDisabledRxStatsWhenNICDisabled(t *testing.T) {
 	}
 }
 
+func TestPacketWithUnknownNetworkProtocolNumber(t *testing.T) {
+	nic := nic{
+		stats:   makeNICStats(tcpip.NICStats{}.FillIn()),
+		enabled: 1,
+	}
+	// IPv4 isn't recognized since we haven't initialized the NIC with an IPv4
+	// endpoint.
+	nic.DeliverNetworkPacket("", "", header.IPv4ProtocolNumber, NewPacketBuffer(PacketBufferOptions{
+		Data: buffer.View([]byte{1, 2, 3, 4}).ToVectorisedView(),
+	}))
+	var count uint64
+	if got, ok := nic.stats.local.UnknownL3ProtocolRcvdPacketCounts.Get(uint64(header.IPv4ProtocolNumber)); ok {
+		count = got.Value()
+	}
+	if count != 1 {
+		t.Errorf("got UnknownL3ProtocolRcvdPacketCounts[header.IPv4ProtocolNumber] = %d, want = 1", count)
+	}
+}
+
+func TestPacketWithUnknownTransportProtocolNumber(t *testing.T) {
+	nic := nic{
+		stack:   &Stack{},
+		stats:   makeNICStats(tcpip.NICStats{}.FillIn()),
+		enabled: 1,
+	}
+	// UDP isn't recognized since we haven't initialized the NIC with a UDP
+	// protocol.
+	nic.DeliverTransportPacket(header.UDPProtocolNumber, NewPacketBuffer(PacketBufferOptions{
+		Data: buffer.View([]byte{1, 2, 3, 4}).ToVectorisedView(),
+	}))
+	var count uint64
+	if got, ok := nic.stats.local.UnknownL4ProtocolRcvdPacketCounts.Get(uint64(header.UDPProtocolNumber)); ok {
+		count = got.Value()
+	}
+	if count != 1 {
+		t.Errorf("got UnknownL4ProtocolRcvdPacketCounts[header.UDPProtocolNumber] = %d, want = 1", count)
+	}
+}
+
 func TestMultiCounterStatsInitialization(t *testing.T) {
 	global := tcpip.NICStats{}.FillIn()
 	nic := nic{
@@ -213,7 +252,10 @@ func TestMultiCounterStatsInitialization(t *testing.T) {
 	}
 	multi := nic.stats.multiCounterNICStats
 	local := nic.stats.local
-	if err := testutil.ValidateMultiCounterStats(reflect.ValueOf(&multi).Elem(), []reflect.Value{reflect.ValueOf(&local).Elem(), reflect.ValueOf(&global).Elem()}); err != nil {
+	if err := testutil.ValidateMultiCounterStats(reflect.ValueOf(&multi).Elem(), []reflect.Value{reflect.ValueOf(&local).Elem(), reflect.ValueOf(&global).Elem()}, testutil.ValidateMultiCounterStatsOptions{
+		ExpectMultiCounterStat:            true,
+		ExpectMultiIntegralStatCounterMap: true,
+	}); err != nil {
 		t.Error(err)
 	}
 }