p2p/discover: add more packet information in logs (#26307)

* p2p/discover: add more packet information in logs

This adds more fields to discv5 packet logs. These can be useful when
debugging multi-packet interactions.

The FINDNODE message also gets an additional field, OpID for debugging
purposes. This field is not encoded onto the wire.

I'm also removing topic system related message types in this change.
These will come back in the future, where support for them will be
guarded by a config flag.

* p2p/discover/v5wire: rename 'Total' to 'RespCount'

The new name captures the meaning of this field better.

Author: fjl

cmd/devp2p/internal/v5test/discv5tests.go

@@ -355,7 +355,7 @@ func (bn *bystander) loop() {
 			wasAdded = true
 			bn.notifyAdded()
 		case *v5wire.Findnode:
-			bn.conn.write(bn.l, &v5wire.Nodes{ReqID: p.ReqID, Total: 1}, nil)
+			bn.conn.write(bn.l, &v5wire.Nodes{ReqID: p.ReqID, RespCount: 1}, nil)
 			wasAdded = true
 			bn.notifyAdded()
 		case *v5wire.TalkRequest:

cmd/devp2p/internal/v5test/framework.go

@@ -44,6 +44,8 @@ func (p *readError) Unwrap() error       { return p.err }
 func (p *readError) RequestID() []byte   { return nil }
 func (p *readError) SetRequestID([]byte) {}
 
+func (p *readError) AppendLogInfo(ctx []interface{}) []interface{} { return ctx }
+
 // readErrorf creates a readError with the given text.
 func readErrorf(format string, args ...interface{}) *readError {
 	return &readError{fmt.Errorf(format, args...)}
@@ -171,16 +173,16 @@ func (tc *conn) findnode(c net.PacketConn, dists []uint) ([]*enode.Node, error)
 			// Check total count. It should be greater than one
 			// and needs to be the same across all responses.
 			if first {
-				if resp.Total == 0 || resp.Total > 6 {
-					return nil, fmt.Errorf("invalid NODES response 'total' %d (not in (0,7))", resp.Total)
+				if resp.RespCount == 0 || resp.RespCount > 6 {
+					return nil, fmt.Errorf("invalid NODES response count %d (not in (0,7))", resp.RespCount)
 				}
-				total = resp.Total
+				total = resp.RespCount
 				n = int(total) - 1
 				first = false
 			} else {
 				n--
-				if resp.Total != total {
-					return nil, fmt.Errorf("invalid NODES response 'total' %d (!= %d)", resp.Total, total)
+				if resp.RespCount != total {
+					return nil, fmt.Errorf("invalid NODES response count %d (!= %d)", resp.RespCount, total)
 				}
 			}
 			// Check nodes.

p2p/discover/v5_udp.go

@@ -70,6 +70,9 @@ type UDPv5 struct {
 	clock        mclock.Clock
 	validSchemes enr.IdentityScheme
 
+	// misc buffers used during message handling
+	logcontext []interface{}
+
 	// talkreq handler registry
 	trlock     sync.Mutex
 	trhandlers map[string]TalkRequestHandler
@@ -158,6 +161,7 @@ func newUDPv5(conn UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv5, error) {
 		activeCallByNode: make(map[enode.ID]*callV5),
 		activeCallByAuth: make(map[v5wire.Nonce]*callV5),
 		callQueue:        make(map[enode.ID][]*callV5),
+
 		// shutdown
 		closeCtx:       closeCtx,
 		cancelCloseCtx: cancelCloseCtx,
@@ -385,7 +389,7 @@ func (t *UDPv5) waitForNodes(c *callV5, distances []uint) ([]*enode.Node, error)
 				nodes = append(nodes, node)
 			}
 			if total == -1 {
-				total = min(int(response.Total), totalNodesResponseLimit)
+				total = min(int(response.RespCount), totalNodesResponseLimit)
 			}
 			if received++; received == total {
 				return nodes, nil
@@ -601,13 +605,18 @@ func (t *UDPv5) sendResponse(toID enode.ID, toAddr *net.UDPAddr, packet v5wire.P
 // send sends a packet to the given node.
 func (t *UDPv5) send(toID enode.ID, toAddr *net.UDPAddr, packet v5wire.Packet, c *v5wire.Whoareyou) (v5wire.Nonce, error) {
 	addr := toAddr.String()
+	t.logcontext = append(t.logcontext[:0], "id", toID, "addr", addr)
+	t.logcontext = packet.AppendLogInfo(t.logcontext)
+
 	enc, nonce, err := t.codec.Encode(toID, addr, packet, c)
 	if err != nil {
-		t.log.Warn(">> "+packet.Name(), "id", toID, "addr", addr, "err", err)
+		t.logcontext = append(t.logcontext, "err", err)
+		t.log.Warn(">> "+packet.Name(), t.logcontext...)
 		return nonce, err
 	}
+
 	_, err = t.conn.WriteToUDP(enc, toAddr)
-	t.log.Trace(">> "+packet.Name(), "id", toID, "addr", addr)
+	t.log.Trace(">> "+packet.Name(), t.logcontext...)
 	return nonce, err
 }
 
@@ -657,7 +666,9 @@ func (t *UDPv5) handlePacket(rawpacket []byte, fromAddr *net.UDPAddr) error {
 	}
 	if packet.Kind() != v5wire.WhoareyouPacket {
 		// WHOAREYOU logged separately to report errors.
-		t.log.Trace("<< "+packet.Name(), "id", fromID, "addr", addr)
+		t.logcontext = append(t.logcontext[:0], "id", fromID, "addr", addr)
+		t.logcontext = packet.AppendLogInfo(t.logcontext)
+		t.log.Trace("<< "+packet.Name(), t.logcontext...)
 	}
 	t.handle(packet, fromID, fromAddr)
 	return nil
@@ -712,7 +723,7 @@ func (t *UDPv5) handle(p v5wire.Packet, fromID enode.ID, fromAddr *net.UDPAddr)
 	case *v5wire.Nodes:
 		t.handleCallResponse(fromID, fromAddr, p)
 	case *v5wire.TalkRequest:
-		t.handleTalkRequest(p, fromID, fromAddr)
+		t.handleTalkRequest(fromID, fromAddr, p)
 	case *v5wire.TalkResponse:
 		t.handleCallResponse(fromID, fromAddr, p)
 	}
@@ -827,7 +838,7 @@ func (t *UDPv5) collectTableNodes(rip net.IP, distances []uint, limit int) []*en
 // packNodes creates NODES response packets for the given node list.
 func packNodes(reqid []byte, nodes []*enode.Node) []*v5wire.Nodes {
 	if len(nodes) == 0 {
-		return []*v5wire.Nodes{{ReqID: reqid, Total: 1}}
+		return []*v5wire.Nodes{{ReqID: reqid, RespCount: 1}}
 	}
 
 	// This limit represents the available space for nodes in output packets. Maximum
@@ -851,13 +862,13 @@ func packNodes(reqid []byte, nodes []*enode.Node) []*v5wire.Nodes {
 		resp = append(resp, p)
 	}
 	for _, msg := range resp {
-		msg.Total = uint8(len(resp))
+		msg.RespCount = uint8(len(resp))
 	}
 	return resp
 }
 
 // handleTalkRequest runs the talk request handler of the requested protocol.
-func (t *UDPv5) handleTalkRequest(p *v5wire.TalkRequest, fromID enode.ID, fromAddr *net.UDPAddr) {
+func (t *UDPv5) handleTalkRequest(fromID enode.ID, fromAddr *net.UDPAddr, p *v5wire.TalkRequest) {
 	t.trlock.Lock()
 	handler := t.trhandlers[p.Protocol]
 	t.trlock.Unlock()

p2p/discover/v5_udp_test.go

@@ -208,8 +208,8 @@ func (test *udpV5Test) expectNodes(wantReqID []byte, wantTotal uint8, wantNodes
 			if !bytes.Equal(p.ReqID, wantReqID) {
 				test.t.Fatalf("wrong request ID %v in response, want %v", p.ReqID, wantReqID)
 			}
-			if p.Total != wantTotal {
-				test.t.Fatalf("wrong total response count %d, want %d", p.Total, wantTotal)
+			if p.RespCount != wantTotal {
+				test.t.Fatalf("wrong total response count %d, want %d", p.RespCount, wantTotal)
 			}
 			for _, record := range p.Nodes {
 				n, _ := enode.New(enode.ValidSchemesForTesting, record)
@@ -301,14 +301,14 @@ func TestUDPv5_findnodeCall(t *testing.T) {
 			t.Fatalf("wrong distances in request: %v", p.Distances)
 		}
 		test.packetIn(&v5wire.Nodes{
-			ReqID: p.ReqID,
-			Total: 2,
-			Nodes: nodesToRecords(nodes[:4]),
+			ReqID:     p.ReqID,
+			RespCount: 2,
+			Nodes:     nodesToRecords(nodes[:4]),
 		})
 		test.packetIn(&v5wire.Nodes{
-			ReqID: p.ReqID,
-			Total: 2,
-			Nodes: nodesToRecords(nodes[4:]),
+			ReqID:     p.ReqID,
+			RespCount: 2,
+			Nodes:     nodesToRecords(nodes[4:]),
 		})
 	})
 
@@ -409,16 +409,16 @@ func TestUDPv5_callTimeoutReset(t *testing.T) {
 	test.waitPacketOut(func(p *v5wire.Findnode, addr *net.UDPAddr, _ v5wire.Nonce) {
 		time.Sleep(respTimeout - 50*time.Millisecond)
 		test.packetIn(&v5wire.Nodes{
-			ReqID: p.ReqID,
-			Total: 2,
-			Nodes: nodesToRecords(nodes[:4]),
+			ReqID:     p.ReqID,
+			RespCount: 2,
+			Nodes:     nodesToRecords(nodes[:4]),
 		})
 
 		time.Sleep(respTimeout - 50*time.Millisecond)
 		test.packetIn(&v5wire.Nodes{
-			ReqID: p.ReqID,
-			Total: 2,
-			Nodes: nodesToRecords(nodes[4:]),
+			ReqID:     p.ReqID,
+			RespCount: 2,
+			Nodes:     nodesToRecords(nodes[4:]),
 		})
 	})
 	if err := <-done; err != nil {

p2p/discover/v5wire/encoding_test.go

@@ -92,7 +92,7 @@ func TestHandshake(t *testing.T) {
 	}
 
 	// A <- B   NODES
-	nodes, _ := net.nodeB.encode(t, net.nodeA, &Nodes{Total: 1})
+	nodes, _ := net.nodeB.encode(t, net.nodeA, &Nodes{RespCount: 1})
 	net.nodeA.expectDecode(t, NodesMsg, nodes)
 }
 
@@ -150,7 +150,7 @@ func TestHandshake_norecord(t *testing.T) {
 	net.nodeB.expectDecode(t, FindnodeMsg, findnode)
 
 	// A <- B   NODES
-	nodes, _ := net.nodeB.encode(t, net.nodeA, &Nodes{Total: 1})
+	nodes, _ := net.nodeB.encode(t, net.nodeA, &Nodes{RespCount: 1})
 	net.nodeA.expectDecode(t, NodesMsg, nodes)
 }
 
@@ -190,7 +190,7 @@ func TestHandshake_rekey(t *testing.T) {
 	net.nodeB.expectDecode(t, FindnodeMsg, findnode)
 
 	// A <- B   NODES
-	nodes, _ := net.nodeB.encode(t, net.nodeA, &Nodes{Total: 1})
+	nodes, _ := net.nodeB.encode(t, net.nodeA, &Nodes{RespCount: 1})
 	net.nodeA.expectDecode(t, NodesMsg, nodes)
 }
 
@@ -225,7 +225,7 @@ func TestHandshake_rekey2(t *testing.T) {
 	net.nodeB.expectDecode(t, FindnodeMsg, findnode)
 
 	// A <- B   NODES
-	nodes, _ := net.nodeB.encode(t, net.nodeA, &Nodes{Total: 1})
+	nodes, _ := net.nodeB.encode(t, net.nodeA, &Nodes{RespCount: 1})
 	net.nodeA.expectDecode(t, NodesMsg, nodes)
 }