go-ethereum/cmd/devp2p/internal/v5test/discv5tests.go
Felix Lange a251bca67c
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.
2023-01-03 12:36:38 +01:00

378 lines
11 KiB
Go

// Copyright 2020 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
package v5test
import (
"bytes"
"net"
"sync"
"time"
"github.com/ethereum/go-ethereum/internal/utesting"
"github.com/ethereum/go-ethereum/p2p/discover/v5wire"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/p2p/netutil"
)
// Suite is the discv5 test suite.
type Suite struct {
Dest *enode.Node
Listen1, Listen2 string // listening addresses
}
func (s *Suite) listen1(log logger) (*conn, net.PacketConn) {
c := newConn(s.Dest, log)
l := c.listen(s.Listen1)
return c, l
}
func (s *Suite) listen2(log logger) (*conn, net.PacketConn, net.PacketConn) {
c := newConn(s.Dest, log)
l1, l2 := c.listen(s.Listen1), c.listen(s.Listen2)
return c, l1, l2
}
func (s *Suite) AllTests() []utesting.Test {
return []utesting.Test{
{Name: "Ping", Fn: s.TestPing},
{Name: "PingLargeRequestID", Fn: s.TestPingLargeRequestID},
{Name: "PingMultiIP", Fn: s.TestPingMultiIP},
{Name: "PingHandshakeInterrupted", Fn: s.TestPingHandshakeInterrupted},
{Name: "TalkRequest", Fn: s.TestTalkRequest},
{Name: "FindnodeZeroDistance", Fn: s.TestFindnodeZeroDistance},
{Name: "FindnodeResults", Fn: s.TestFindnodeResults},
}
}
// TestPing sends PING and expects a PONG response.
func (s *Suite) TestPing(t *utesting.T) {
conn, l1 := s.listen1(t)
defer conn.close()
ping := &v5wire.Ping{ReqID: conn.nextReqID()}
switch resp := conn.reqresp(l1, ping).(type) {
case *v5wire.Pong:
checkPong(t, resp, ping, l1)
default:
t.Fatal("expected PONG, got", resp.Name())
}
}
func checkPong(t *utesting.T, pong *v5wire.Pong, ping *v5wire.Ping, c net.PacketConn) {
if !bytes.Equal(pong.ReqID, ping.ReqID) {
t.Fatalf("wrong request ID %x in PONG, want %x", pong.ReqID, ping.ReqID)
}
if !pong.ToIP.Equal(laddr(c).IP) {
t.Fatalf("wrong destination IP %v in PONG, want %v", pong.ToIP, laddr(c).IP)
}
if int(pong.ToPort) != laddr(c).Port {
t.Fatalf("wrong destination port %v in PONG, want %v", pong.ToPort, laddr(c).Port)
}
}
// TestPingLargeRequestID sends PING with a 9-byte request ID, which isn't allowed by the spec.
// The remote node should not respond.
func (s *Suite) TestPingLargeRequestID(t *utesting.T) {
conn, l1 := s.listen1(t)
defer conn.close()
ping := &v5wire.Ping{ReqID: make([]byte, 9)}
switch resp := conn.reqresp(l1, ping).(type) {
case *v5wire.Pong:
t.Errorf("PONG response with unknown request ID %x", resp.ReqID)
case *readError:
if resp.err == v5wire.ErrInvalidReqID {
t.Error("response with oversized request ID")
} else if !netutil.IsTimeout(resp.err) {
t.Error(resp)
}
}
}
// TestPingMultiIP establishes a session from one IP as usual. The session is then reused
// on another IP, which shouldn't work. The remote node should respond with WHOAREYOU for
// the attempt from a different IP.
func (s *Suite) TestPingMultiIP(t *utesting.T) {
conn, l1, l2 := s.listen2(t)
defer conn.close()
// Create the session on l1.
ping := &v5wire.Ping{ReqID: conn.nextReqID()}
resp := conn.reqresp(l1, ping)
if resp.Kind() != v5wire.PongMsg {
t.Fatal("expected PONG, got", resp)
}
checkPong(t, resp.(*v5wire.Pong), ping, l1)
// Send on l2. This reuses the session because there is only one codec.
ping2 := &v5wire.Ping{ReqID: conn.nextReqID()}
conn.write(l2, ping2, nil)
switch resp := conn.read(l2).(type) {
case *v5wire.Pong:
t.Fatalf("remote responded to PING from %v for session on IP %v", laddr(l2).IP, laddr(l1).IP)
case *v5wire.Whoareyou:
t.Logf("got WHOAREYOU for new session as expected")
resp.Node = s.Dest
conn.write(l2, ping2, resp)
default:
t.Fatal("expected WHOAREYOU, got", resp)
}
// Catch the PONG on l2.
switch resp := conn.read(l2).(type) {
case *v5wire.Pong:
checkPong(t, resp, ping2, l2)
default:
t.Fatal("expected PONG, got", resp)
}
// Try on l1 again.
ping3 := &v5wire.Ping{ReqID: conn.nextReqID()}
conn.write(l1, ping3, nil)
switch resp := conn.read(l1).(type) {
case *v5wire.Pong:
t.Fatalf("remote responded to PING from %v for session on IP %v", laddr(l1).IP, laddr(l2).IP)
case *v5wire.Whoareyou:
t.Logf("got WHOAREYOU for new session as expected")
default:
t.Fatal("expected WHOAREYOU, got", resp)
}
}
// TestPingHandshakeInterrupted starts a handshake, but doesn't finish it and sends a second ordinary message
// packet instead of a handshake message packet. The remote node should respond with
// another WHOAREYOU challenge for the second packet.
func (s *Suite) TestPingHandshakeInterrupted(t *utesting.T) {
conn, l1 := s.listen1(t)
defer conn.close()
// First PING triggers challenge.
ping := &v5wire.Ping{ReqID: conn.nextReqID()}
conn.write(l1, ping, nil)
switch resp := conn.read(l1).(type) {
case *v5wire.Whoareyou:
t.Logf("got WHOAREYOU for PING")
default:
t.Fatal("expected WHOAREYOU, got", resp)
}
// Send second PING.
ping2 := &v5wire.Ping{ReqID: conn.nextReqID()}
switch resp := conn.reqresp(l1, ping2).(type) {
case *v5wire.Pong:
checkPong(t, resp, ping2, l1)
default:
t.Fatal("expected WHOAREYOU, got", resp)
}
}
// TestTalkRequest sends TALKREQ and expects an empty TALKRESP response.
func (s *Suite) TestTalkRequest(t *utesting.T) {
conn, l1 := s.listen1(t)
defer conn.close()
// Non-empty request ID.
id := conn.nextReqID()
resp := conn.reqresp(l1, &v5wire.TalkRequest{ReqID: id, Protocol: "test-protocol"})
switch resp := resp.(type) {
case *v5wire.TalkResponse:
if !bytes.Equal(resp.ReqID, id) {
t.Fatalf("wrong request ID %x in TALKRESP, want %x", resp.ReqID, id)
}
if len(resp.Message) > 0 {
t.Fatalf("non-empty message %x in TALKRESP", resp.Message)
}
default:
t.Fatal("expected TALKRESP, got", resp.Name())
}
// Empty request ID.
resp = conn.reqresp(l1, &v5wire.TalkRequest{Protocol: "test-protocol"})
switch resp := resp.(type) {
case *v5wire.TalkResponse:
if len(resp.ReqID) > 0 {
t.Fatalf("wrong request ID %x in TALKRESP, want empty byte array", resp.ReqID)
}
if len(resp.Message) > 0 {
t.Fatalf("non-empty message %x in TALKRESP", resp.Message)
}
default:
t.Fatal("expected TALKRESP, got", resp.Name())
}
}
// TestFindnodeZeroDistance checks that the remote node returns itself for FINDNODE with distance zero.
func (s *Suite) TestFindnodeZeroDistance(t *utesting.T) {
conn, l1 := s.listen1(t)
defer conn.close()
nodes, err := conn.findnode(l1, []uint{0})
if err != nil {
t.Fatal(err)
}
if len(nodes) != 1 {
t.Fatalf("remote returned more than one node for FINDNODE [0]")
}
if nodes[0].ID() != conn.remote.ID() {
t.Errorf("ID of response node is %v, want %v", nodes[0].ID(), conn.remote.ID())
}
}
// TestFindnodeResults pings the node under test from multiple nodes. After waiting for them to be
// accepted into the remote table, the test checks that they are returned by FINDNODE.
func (s *Suite) TestFindnodeResults(t *utesting.T) {
// Create bystanders.
nodes := make([]*bystander, 5)
added := make(chan enode.ID, len(nodes))
for i := range nodes {
nodes[i] = newBystander(t, s, added)
defer nodes[i].close()
}
// Get them added to the remote table.
timeout := 60 * time.Second
timeoutCh := time.After(timeout)
for count := 0; count < len(nodes); {
select {
case id := <-added:
t.Logf("bystander node %v added to remote table", id)
count++
case <-timeoutCh:
t.Errorf("remote added %d bystander nodes in %v, need %d to continue", count, timeout, len(nodes))
t.Logf("this can happen if the node has a non-empty table from previous runs")
return
}
}
t.Logf("all %d bystander nodes were added", len(nodes))
// Collect our nodes by distance.
var dists []uint
expect := make(map[enode.ID]*enode.Node)
for _, bn := range nodes {
n := bn.conn.localNode.Node()
expect[n.ID()] = n
d := uint(enode.LogDist(n.ID(), s.Dest.ID()))
if !containsUint(dists, d) {
dists = append(dists, d)
}
}
// Send FINDNODE for all distances.
conn, l1 := s.listen1(t)
defer conn.close()
foundNodes, err := conn.findnode(l1, dists)
if err != nil {
t.Fatal(err)
}
t.Logf("remote returned %d nodes for distance list %v", len(foundNodes), dists)
for _, n := range foundNodes {
delete(expect, n.ID())
}
if len(expect) > 0 {
t.Errorf("missing %d nodes in FINDNODE result", len(expect))
t.Logf("this can happen if the test is run multiple times in quick succession")
t.Logf("and the remote node hasn't removed dead nodes from previous runs yet")
} else {
t.Logf("all %d expected nodes were returned", len(nodes))
}
}
// A bystander is a node whose only purpose is filling a spot in the remote table.
type bystander struct {
dest *enode.Node
conn *conn
l net.PacketConn
addedCh chan enode.ID
done sync.WaitGroup
}
func newBystander(t *utesting.T, s *Suite, added chan enode.ID) *bystander {
conn, l := s.listen1(t)
conn.setEndpoint(l) // bystander nodes need IP/port to get pinged
bn := &bystander{
conn: conn,
l: l,
dest: s.Dest,
addedCh: added,
}
bn.done.Add(1)
go bn.loop()
return bn
}
// id returns the node ID of the bystander.
func (bn *bystander) id() enode.ID {
return bn.conn.localNode.ID()
}
// close shuts down loop.
func (bn *bystander) close() {
bn.conn.close()
bn.done.Wait()
}
// loop answers packets from the remote node until quit.
func (bn *bystander) loop() {
defer bn.done.Done()
var (
lastPing time.Time
wasAdded bool
)
for {
// Ping the remote node.
if !wasAdded && time.Since(lastPing) > 10*time.Second {
bn.conn.reqresp(bn.l, &v5wire.Ping{
ReqID: bn.conn.nextReqID(),
ENRSeq: bn.dest.Seq(),
})
lastPing = time.Now()
}
// Answer packets.
switch p := bn.conn.read(bn.l).(type) {
case *v5wire.Ping:
bn.conn.write(bn.l, &v5wire.Pong{
ReqID: p.ReqID,
ENRSeq: bn.conn.localNode.Seq(),
ToIP: bn.dest.IP(),
ToPort: uint16(bn.dest.UDP()),
}, nil)
wasAdded = true
bn.notifyAdded()
case *v5wire.Findnode:
bn.conn.write(bn.l, &v5wire.Nodes{ReqID: p.ReqID, RespCount: 1}, nil)
wasAdded = true
bn.notifyAdded()
case *v5wire.TalkRequest:
bn.conn.write(bn.l, &v5wire.TalkResponse{ReqID: p.ReqID}, nil)
case *readError:
if !netutil.IsTemporaryError(p.err) {
bn.conn.logf("shutting down: %v", p.err)
return
}
}
}
}
func (bn *bystander) notifyAdded() {
if bn.addedCh != nil {
bn.addedCh <- bn.id()
bn.addedCh = nil
}
}