go-ethereum/p2p/discover/v5_udp_test.go
Nishant Das 7a63faf734
p2p/discover: add helper methods to UDPv5 (#20918)
This adds two new methods to UDPv5, AllNodes and LocalNode.

AllNodes returns all the nodes stored in the local table; this is
useful for the purposes of metrics collection and also debugging any
potential issues with other discovery v5 implementations.

LocalNode returns the local node object. The reason for exposing this
is so that users can modify and set/delete new key-value entries in
the local record.
2020-04-16 15:58:37 +02:00

645 lines
18 KiB
Go

// Copyright 2019 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package discover
import (
"bytes"
"crypto/ecdsa"
"encoding/binary"
"fmt"
"math/rand"
"net"
"reflect"
"testing"
"time"
"github.com/ethereum/go-ethereum/internal/testlog"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p/enode"
"github.com/ethereum/go-ethereum/p2p/enr"
"github.com/ethereum/go-ethereum/rlp"
)
// Real sockets, real crypto: this test checks end-to-end connectivity for UDPv5.
func TestEndToEndV5(t *testing.T) {
t.Parallel()
var nodes []*UDPv5
for i := 0; i < 5; i++ {
var cfg Config
if len(nodes) > 0 {
bn := nodes[0].Self()
cfg.Bootnodes = []*enode.Node{bn}
}
node := startLocalhostV5(t, cfg)
nodes = append(nodes, node)
defer node.Close()
}
last := nodes[len(nodes)-1]
target := nodes[rand.Intn(len(nodes)-2)].Self()
results := last.Lookup(target.ID())
if len(results) == 0 || results[0].ID() != target.ID() {
t.Fatalf("lookup returned wrong results: %v", results)
}
}
func startLocalhostV5(t *testing.T, cfg Config) *UDPv5 {
cfg.PrivateKey = newkey()
db, _ := enode.OpenDB("")
ln := enode.NewLocalNode(db, cfg.PrivateKey)
// Prefix logs with node ID.
lprefix := fmt.Sprintf("(%s)", ln.ID().TerminalString())
lfmt := log.TerminalFormat(false)
cfg.Log = testlog.Logger(t, log.LvlTrace)
cfg.Log.SetHandler(log.FuncHandler(func(r *log.Record) error {
t.Logf("%s %s", lprefix, lfmt.Format(r))
return nil
}))
// Listen.
socket, err := net.ListenUDP("udp4", &net.UDPAddr{IP: net.IP{127, 0, 0, 1}})
if err != nil {
t.Fatal(err)
}
realaddr := socket.LocalAddr().(*net.UDPAddr)
ln.SetStaticIP(realaddr.IP)
ln.Set(enr.UDP(realaddr.Port))
udp, err := ListenV5(socket, ln, cfg)
if err != nil {
t.Fatal(err)
}
return udp
}
// This test checks that incoming PING calls are handled correctly.
func TestUDPv5_pingHandling(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
defer test.close()
test.packetIn(&pingV5{ReqID: []byte("foo")})
test.waitPacketOut(func(p *pongV5, addr *net.UDPAddr, authTag []byte) {
if !bytes.Equal(p.ReqID, []byte("foo")) {
t.Error("wrong request ID in response:", p.ReqID)
}
if p.ENRSeq != test.table.self().Seq() {
t.Error("wrong ENR sequence number in response:", p.ENRSeq)
}
})
}
// This test checks that incoming 'unknown' packets trigger the handshake.
func TestUDPv5_unknownPacket(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
defer test.close()
authTag := [12]byte{1, 2, 3}
check := func(p *whoareyouV5, wantSeq uint64) {
t.Helper()
if !bytes.Equal(p.AuthTag, authTag[:]) {
t.Error("wrong token in WHOAREYOU:", p.AuthTag, authTag[:])
}
if p.IDNonce == ([32]byte{}) {
t.Error("all zero ID nonce")
}
if p.RecordSeq != wantSeq {
t.Errorf("wrong record seq %d in WHOAREYOU, want %d", p.RecordSeq, wantSeq)
}
}
// Unknown packet from unknown node.
test.packetIn(&unknownV5{AuthTag: authTag[:]})
test.waitPacketOut(func(p *whoareyouV5, addr *net.UDPAddr, _ []byte) {
check(p, 0)
})
// Make node known.
n := test.getNode(test.remotekey, test.remoteaddr).Node()
test.table.addSeenNode(wrapNode(n))
test.packetIn(&unknownV5{AuthTag: authTag[:]})
test.waitPacketOut(func(p *whoareyouV5, addr *net.UDPAddr, _ []byte) {
check(p, n.Seq())
})
}
// This test checks that incoming FINDNODE calls are handled correctly.
func TestUDPv5_findnodeHandling(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
defer test.close()
// Create test nodes and insert them into the table.
nodes := nodesAtDistance(test.table.self().ID(), 253, 10)
fillTable(test.table, wrapNodes(nodes))
// Requesting with distance zero should return the node's own record.
test.packetIn(&findnodeV5{ReqID: []byte{0}, Distance: 0})
test.expectNodes([]byte{0}, 1, []*enode.Node{test.udp.Self()})
// Requesting with distance > 256 caps it at 256.
test.packetIn(&findnodeV5{ReqID: []byte{1}, Distance: 4234098})
test.expectNodes([]byte{1}, 1, nil)
// This request gets no nodes because the corresponding bucket is empty.
test.packetIn(&findnodeV5{ReqID: []byte{2}, Distance: 254})
test.expectNodes([]byte{2}, 1, nil)
// This request gets all test nodes.
test.packetIn(&findnodeV5{ReqID: []byte{3}, Distance: 253})
test.expectNodes([]byte{3}, 4, nodes)
}
func (test *udpV5Test) expectNodes(wantReqID []byte, wantTotal uint8, wantNodes []*enode.Node) {
nodeSet := make(map[enode.ID]*enr.Record)
for _, n := range wantNodes {
nodeSet[n.ID()] = n.Record()
}
for {
test.waitPacketOut(func(p *nodesV5, addr *net.UDPAddr, authTag []byte) {
if len(p.Nodes) > 3 {
test.t.Fatalf("too many nodes in response")
}
if p.Total != wantTotal {
test.t.Fatalf("wrong total response count %d", p.Total)
}
if !bytes.Equal(p.ReqID, wantReqID) {
test.t.Fatalf("wrong request ID in response: %v", p.ReqID)
}
for _, record := range p.Nodes {
n, _ := enode.New(enode.ValidSchemesForTesting, record)
want := nodeSet[n.ID()]
if want == nil {
test.t.Fatalf("unexpected node in response: %v", n)
}
if !reflect.DeepEqual(record, want) {
test.t.Fatalf("wrong record in response: %v", n)
}
delete(nodeSet, n.ID())
}
})
if len(nodeSet) == 0 {
return
}
}
}
// This test checks that outgoing PING calls work.
func TestUDPv5_pingCall(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
defer test.close()
remote := test.getNode(test.remotekey, test.remoteaddr).Node()
done := make(chan error, 1)
// This ping times out.
go func() {
_, err := test.udp.ping(remote)
done <- err
}()
test.waitPacketOut(func(p *pingV5, addr *net.UDPAddr, authTag []byte) {})
if err := <-done; err != errTimeout {
t.Fatalf("want errTimeout, got %q", err)
}
// This ping works.
go func() {
_, err := test.udp.ping(remote)
done <- err
}()
test.waitPacketOut(func(p *pingV5, addr *net.UDPAddr, authTag []byte) {
test.packetInFrom(test.remotekey, test.remoteaddr, &pongV5{ReqID: p.ReqID})
})
if err := <-done; err != nil {
t.Fatal(err)
}
// This ping gets a reply from the wrong endpoint.
go func() {
_, err := test.udp.ping(remote)
done <- err
}()
test.waitPacketOut(func(p *pingV5, addr *net.UDPAddr, authTag []byte) {
wrongAddr := &net.UDPAddr{IP: net.IP{33, 44, 55, 22}, Port: 10101}
test.packetInFrom(test.remotekey, wrongAddr, &pongV5{ReqID: p.ReqID})
})
if err := <-done; err != errTimeout {
t.Fatalf("want errTimeout for reply from wrong IP, got %q", err)
}
}
// This test checks that outgoing FINDNODE calls work and multiple NODES
// replies are aggregated.
func TestUDPv5_findnodeCall(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
defer test.close()
// Launch the request:
var (
distance = 230
remote = test.getNode(test.remotekey, test.remoteaddr).Node()
nodes = nodesAtDistance(remote.ID(), distance, 8)
done = make(chan error, 1)
response []*enode.Node
)
go func() {
var err error
response, err = test.udp.findnode(remote, distance)
done <- err
}()
// Serve the responses:
test.waitPacketOut(func(p *findnodeV5, addr *net.UDPAddr, authTag []byte) {
if p.Distance != uint(distance) {
t.Fatalf("wrong bucket: %d", p.Distance)
}
test.packetIn(&nodesV5{
ReqID: p.ReqID,
Total: 2,
Nodes: nodesToRecords(nodes[:4]),
})
test.packetIn(&nodesV5{
ReqID: p.ReqID,
Total: 2,
Nodes: nodesToRecords(nodes[4:]),
})
})
// Check results:
if err := <-done; err != nil {
t.Fatalf("unexpected error: %v", err)
}
if !reflect.DeepEqual(response, nodes) {
t.Fatalf("wrong nodes in response")
}
// TODO: check invalid IPs
// TODO: check invalid/unsigned record
}
// This test checks that pending calls are re-sent when a handshake happens.
func TestUDPv5_callResend(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
defer test.close()
remote := test.getNode(test.remotekey, test.remoteaddr).Node()
done := make(chan error, 2)
go func() {
_, err := test.udp.ping(remote)
done <- err
}()
go func() {
_, err := test.udp.ping(remote)
done <- err
}()
// Ping answered by WHOAREYOU.
test.waitPacketOut(func(p *pingV5, addr *net.UDPAddr, authTag []byte) {
test.packetIn(&whoareyouV5{AuthTag: authTag})
})
// Ping should be re-sent.
test.waitPacketOut(func(p *pingV5, addr *net.UDPAddr, authTag []byte) {
test.packetIn(&pongV5{ReqID: p.ReqID})
})
// Answer the other ping.
test.waitPacketOut(func(p *pingV5, addr *net.UDPAddr, authTag []byte) {
test.packetIn(&pongV5{ReqID: p.ReqID})
})
if err := <-done; err != nil {
t.Fatalf("unexpected ping error: %v", err)
}
if err := <-done; err != nil {
t.Fatalf("unexpected ping error: %v", err)
}
}
// This test ensures we don't allow multiple rounds of WHOAREYOU for a single call.
func TestUDPv5_multipleHandshakeRounds(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
defer test.close()
remote := test.getNode(test.remotekey, test.remoteaddr).Node()
done := make(chan error, 1)
go func() {
_, err := test.udp.ping(remote)
done <- err
}()
// Ping answered by WHOAREYOU.
test.waitPacketOut(func(p *pingV5, addr *net.UDPAddr, authTag []byte) {
test.packetIn(&whoareyouV5{AuthTag: authTag})
})
// Ping answered by WHOAREYOU again.
test.waitPacketOut(func(p *pingV5, addr *net.UDPAddr, authTag []byte) {
test.packetIn(&whoareyouV5{AuthTag: authTag})
})
if err := <-done; err != errTimeout {
t.Fatalf("unexpected ping error: %q", err)
}
}
// This test checks that calls with n replies may take up to n * respTimeout.
func TestUDPv5_callTimeoutReset(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
defer test.close()
// Launch the request:
var (
distance = 230
remote = test.getNode(test.remotekey, test.remoteaddr).Node()
nodes = nodesAtDistance(remote.ID(), distance, 8)
done = make(chan error, 1)
)
go func() {
_, err := test.udp.findnode(remote, distance)
done <- err
}()
// Serve two responses, slowly.
test.waitPacketOut(func(p *findnodeV5, addr *net.UDPAddr, authTag []byte) {
time.Sleep(respTimeout - 50*time.Millisecond)
test.packetIn(&nodesV5{
ReqID: p.ReqID,
Total: 2,
Nodes: nodesToRecords(nodes[:4]),
})
time.Sleep(respTimeout - 50*time.Millisecond)
test.packetIn(&nodesV5{
ReqID: p.ReqID,
Total: 2,
Nodes: nodesToRecords(nodes[4:]),
})
})
if err := <-done; err != nil {
t.Fatalf("unexpected error: %q", err)
}
}
// This test checks that lookup works.
func TestUDPv5_lookup(t *testing.T) {
t.Parallel()
test := newUDPV5Test(t)
// Lookup on empty table returns no nodes.
if results := test.udp.Lookup(lookupTestnet.target.id()); len(results) > 0 {
t.Fatalf("lookup on empty table returned %d results: %#v", len(results), results)
}
// Ensure the tester knows all nodes in lookupTestnet by IP.
for d, nn := range lookupTestnet.dists {
for i, key := range nn {
n := lookupTestnet.node(d, i)
test.getNode(key, &net.UDPAddr{IP: n.IP(), Port: n.UDP()})
}
}
// Seed table with initial node.
fillTable(test.table, []*node{wrapNode(lookupTestnet.node(256, 0))})
// Start the lookup.
resultC := make(chan []*enode.Node, 1)
go func() {
resultC <- test.udp.Lookup(lookupTestnet.target.id())
test.close()
}()
// Answer lookup packets.
for done := false; !done; {
done = test.waitPacketOut(func(p packetV5, to *net.UDPAddr, authTag []byte) {
recipient, key := lookupTestnet.nodeByAddr(to)
switch p := p.(type) {
case *pingV5:
test.packetInFrom(key, to, &pongV5{ReqID: p.ReqID})
case *findnodeV5:
nodes := lookupTestnet.neighborsAtDistance(recipient, p.Distance, 3)
response := &nodesV5{ReqID: p.ReqID, Total: 1, Nodes: nodesToRecords(nodes)}
test.packetInFrom(key, to, response)
}
})
}
// Verify result nodes.
checkLookupResults(t, lookupTestnet, <-resultC)
}
// This test checks the local node can be utilised to set key-values.
func TestUDPv5_LocalNode(t *testing.T) {
t.Parallel()
var cfg Config
node := startLocalhostV5(t, cfg)
defer node.Close()
localNd := node.LocalNode()
// set value in node's local record
testVal := [4]byte{'A', 'B', 'C', 'D'}
localNd.Set(enr.WithEntry("testing", &testVal))
// retrieve the value from self to make sure it matches.
outputVal := [4]byte{}
if err := node.Self().Load(enr.WithEntry("testing", &outputVal)); err != nil {
t.Errorf("Could not load value from record: %v", err)
}
if testVal != outputVal {
t.Errorf("Wanted %#x to be retrieved from the record but instead got %#x", testVal, outputVal)
}
}
// udpV5Test is the framework for all tests above.
// It runs the UDPv5 transport on a virtual socket and allows testing outgoing packets.
type udpV5Test struct {
t *testing.T
pipe *dgramPipe
table *Table
db *enode.DB
udp *UDPv5
localkey, remotekey *ecdsa.PrivateKey
remoteaddr *net.UDPAddr
nodesByID map[enode.ID]*enode.LocalNode
nodesByIP map[string]*enode.LocalNode
}
type testCodec struct {
test *udpV5Test
id enode.ID
ctr uint64
}
type testCodecFrame struct {
NodeID enode.ID
AuthTag []byte
Ptype byte
Packet rlp.RawValue
}
func (c *testCodec) encode(toID enode.ID, addr string, p packetV5, _ *whoareyouV5) ([]byte, []byte, error) {
c.ctr++
authTag := make([]byte, 8)
binary.BigEndian.PutUint64(authTag, c.ctr)
penc, _ := rlp.EncodeToBytes(p)
frame, err := rlp.EncodeToBytes(testCodecFrame{c.id, authTag, p.kind(), penc})
return frame, authTag, err
}
func (c *testCodec) decode(input []byte, addr string) (enode.ID, *enode.Node, packetV5, error) {
frame, p, err := c.decodeFrame(input)
if err != nil {
return enode.ID{}, nil, nil, err
}
if p.kind() == p_whoareyouV5 {
frame.NodeID = enode.ID{} // match wireCodec behavior
}
return frame.NodeID, nil, p, nil
}
func (c *testCodec) decodeFrame(input []byte) (frame testCodecFrame, p packetV5, err error) {
if err = rlp.DecodeBytes(input, &frame); err != nil {
return frame, nil, fmt.Errorf("invalid frame: %v", err)
}
switch frame.Ptype {
case p_unknownV5:
dec := new(unknownV5)
err = rlp.DecodeBytes(frame.Packet, &dec)
p = dec
case p_whoareyouV5:
dec := new(whoareyouV5)
err = rlp.DecodeBytes(frame.Packet, &dec)
p = dec
default:
p, err = decodePacketBodyV5(frame.Ptype, frame.Packet)
}
return frame, p, err
}
func newUDPV5Test(t *testing.T) *udpV5Test {
test := &udpV5Test{
t: t,
pipe: newpipe(),
localkey: newkey(),
remotekey: newkey(),
remoteaddr: &net.UDPAddr{IP: net.IP{10, 0, 1, 99}, Port: 30303},
nodesByID: make(map[enode.ID]*enode.LocalNode),
nodesByIP: make(map[string]*enode.LocalNode),
}
test.db, _ = enode.OpenDB("")
ln := enode.NewLocalNode(test.db, test.localkey)
ln.SetStaticIP(net.IP{10, 0, 0, 1})
ln.Set(enr.UDP(30303))
test.udp, _ = ListenV5(test.pipe, ln, Config{
PrivateKey: test.localkey,
Log: testlog.Logger(t, log.LvlTrace),
ValidSchemes: enode.ValidSchemesForTesting,
})
test.udp.codec = &testCodec{test: test, id: ln.ID()}
test.table = test.udp.tab
test.nodesByID[ln.ID()] = ln
// Wait for initial refresh so the table doesn't send unexpected findnode.
<-test.table.initDone
return test
}
// handles a packet as if it had been sent to the transport.
func (test *udpV5Test) packetIn(packet packetV5) {
test.t.Helper()
test.packetInFrom(test.remotekey, test.remoteaddr, packet)
}
// handles a packet as if it had been sent to the transport by the key/endpoint.
func (test *udpV5Test) packetInFrom(key *ecdsa.PrivateKey, addr *net.UDPAddr, packet packetV5) {
test.t.Helper()
ln := test.getNode(key, addr)
codec := &testCodec{test: test, id: ln.ID()}
enc, _, err := codec.encode(test.udp.Self().ID(), addr.String(), packet, nil)
if err != nil {
test.t.Errorf("%s encode error: %v", packet.name(), err)
}
if test.udp.dispatchReadPacket(addr, enc) {
<-test.udp.readNextCh // unblock UDPv5.dispatch
}
}
// getNode ensures the test knows about a node at the given endpoint.
func (test *udpV5Test) getNode(key *ecdsa.PrivateKey, addr *net.UDPAddr) *enode.LocalNode {
id := encodePubkey(&key.PublicKey).id()
ln := test.nodesByID[id]
if ln == nil {
db, _ := enode.OpenDB("")
ln = enode.NewLocalNode(db, key)
ln.SetStaticIP(addr.IP)
ln.Set(enr.UDP(addr.Port))
test.nodesByID[id] = ln
}
test.nodesByIP[string(addr.IP)] = ln
return ln
}
func (test *udpV5Test) waitPacketOut(validate interface{}) (closed bool) {
test.t.Helper()
fn := reflect.ValueOf(validate)
exptype := fn.Type().In(0)
dgram, err := test.pipe.receive()
if err == errClosed {
return true
}
if err == errTimeout {
test.t.Fatalf("timed out waiting for %v", exptype)
return false
}
ln := test.nodesByIP[string(dgram.to.IP)]
if ln == nil {
test.t.Fatalf("attempt to send to non-existing node %v", &dgram.to)
return false
}
codec := &testCodec{test: test, id: ln.ID()}
frame, p, err := codec.decodeFrame(dgram.data)
if err != nil {
test.t.Errorf("sent packet decode error: %v", err)
return false
}
if !reflect.TypeOf(p).AssignableTo(exptype) {
test.t.Errorf("sent packet type mismatch, got: %v, want: %v", reflect.TypeOf(p), exptype)
return false
}
fn.Call([]reflect.Value{reflect.ValueOf(p), reflect.ValueOf(&dgram.to), reflect.ValueOf(frame.AuthTag)})
return false
}
func (test *udpV5Test) close() {
test.t.Helper()
test.udp.Close()
test.db.Close()
for id, n := range test.nodesByID {
if id != test.udp.Self().ID() {
n.Database().Close()
}
}
if len(test.pipe.queue) != 0 {
test.t.Fatalf("%d unmatched UDP packets in queue", len(test.pipe.queue))
}
}