// Copyright 2017 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 protocols
import (
"bytes"
"context"
"errors"
"fmt"
"testing"
"time"
"github.com/dexon-foundation/dexon/rlp"
"github.com/dexon-foundation/dexon/p2p"
"github.com/dexon-foundation/dexon/p2p/enode"
"github.com/dexon-foundation/dexon/p2p/simulations/adapters"
p2ptest "github.com/dexon-foundation/dexon/p2p/testing"
)
// handshake message type
type hs0 struct {
C uint
}
// message to kill/drop the peer with nodeID
type kill struct {
C enode.ID
}
// message to drop connection
type drop struct {
}
/// protoHandshake represents module-independent aspects of the protocol and is
// the first message peers send and receive as part the initial exchange
type protoHandshake struct {
Version uint // local and remote peer should have identical version
NetworkID string // local and remote peer should have identical network id
}
// checkProtoHandshake verifies local and remote protoHandshakes match
func checkProtoHandshake(testVersion uint, testNetworkID string) func(interface{}) error {
return func(rhs interface{}) error {
remote := rhs.(*protoHandshake)
if remote.NetworkID != testNetworkID {
return fmt.Errorf("%s (!= %s)", remote.NetworkID, testNetworkID)
}
if remote.Version != testVersion {
return fmt.Errorf("%d (!= %d)", remote.Version, testVersion)
}
return nil
}
}
// newProtocol sets up a protocol
// the run function here demonstrates a typical protocol using peerPool, handshake
// and messages registered to handlers
func newProtocol(pp *p2ptest.TestPeerPool) func(*p2p.Peer, p2p.MsgReadWriter) error {
spec := &Spec{
Name: "test",
Version: 42,
MaxMsgSize: 10 * 1024,
Messages: []interface{}{
protoHandshake{},
hs0{},
kill{},
drop{},
},
}
return func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
peer := NewPeer(p, rw, spec)
// initiate one-off protohandshake and check validity
ctx, cancel := context.WithTimeout(context.Background(), time.Second)
defer cancel()
phs := &protoHandshake{42, "420"}
hsCheck := checkProtoHandshake(phs.Version, phs.NetworkID)
_, err := peer.Handshake(ctx, phs, hsCheck)
if err != nil {
return err
}
lhs := &hs0{42}
// module handshake demonstrating a simple repeatable exchange of same-type message
hs, err := peer.Handshake(ctx, lhs, nil)
if err != nil {
return err
}
if rmhs := hs.(*hs0); rmhs.C > lhs.C {
return fmt.Errorf("handshake mismatch remote %v > local %v", rmhs.C, lhs.C)
}
handle := func(ctx context.Context, msg interface{}) error {
switch msg := msg.(type) {
case *protoHandshake:
return errors.New("duplicate handshake")
case *hs0:
rhs := msg
if rhs.C > lhs.C {
return fmt.Errorf("handshake mismatch remote %v > local %v", rhs.C, lhs.C)
}
lhs.C += rhs.C
return peer.Send(ctx, lhs)
case *kill:
// demonstrates use of peerPool, killing another peer connection as a response to a message
id := msg.C
pp.Get(id).Drop(errors.New("killed"))
return nil
case *drop:
// for testing we can trigger self induced disconnect upon receiving drop message
return errors.New("dropped")
default:
return fmt.Errorf("unknown message type: %T", msg)
}
}
pp.Add(peer)
defer pp.Remove(peer)
return peer.Run(handle)
}
}
func protocolTester(pp *p2ptest.TestPeerPool) *p2ptest.ProtocolTester {
conf := adapters.RandomNodeConfig()
return p2ptest.NewProtocolTester(conf.ID, 2, newProtocol(pp))
}
func protoHandshakeExchange(id enode.ID, proto *protoHandshake) []p2ptest.Exchange {
return []p2ptest.Exchange{
{
Expects: []p2ptest.Expect{
{
Code: 0,
Msg: &protoHandshake{42, "420"},
Peer: id,
},
},
},
{
Triggers: []p2ptest.Trigger{
{
Code: 0,
Msg: proto,
Peer: id,
},
},
},
}
}
func runProtoHandshake(t *testing.T, proto *protoHandshake, errs ...error) {
pp := p2ptest.NewTestPeerPool()
s := protocolTester(pp)
// TODO: make this more than one handshake
node := s.Nodes[0]
if err := s.TestExchanges(protoHandshakeExchange(node.ID(), proto)...); err != nil {
t.Fatal(err)
}
var disconnects []*p2ptest.Disconnect
for i, err := range errs {
disconnects = append(disconnects, &p2ptest.Disconnect{Peer: s.Nodes[i].ID(), Error: err})
}
if err := s.TestDisconnected(disconnects...); err != nil {
t.Fatal(err)
}
}
type dummyHook struct {
peer *Peer
size uint32
msg interface{}
send bool
err error
waitC chan struct{}
}
type dummyMsg struct {
Content string
}
func (d *dummyHook) Send(peer *Peer, size uint32, msg interface{}) error {
d.peer = peer
d.size = size
d.msg = msg
d.send = true
return d.err
}
func (d *dummyHook) Receive(peer *Peer, size uint32, msg interface{}) error {
d.peer = peer
d.size = size
d.msg = msg
d.send = false
d.waitC <- struct{}{}
return d.err
}
func TestProtocolHook(t *testing.T) {
testHook := &dummyHook{
waitC: make(chan struct{}, 1),
}
spec := &Spec{
Name: "test",
Version: 42,
MaxMsgSize: 10 * 1024,
Messages: []interface{}{
dummyMsg{},
},
Hook: testHook,
}
runFunc := func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
peer := NewPeer(p, rw, spec)
ctx := context.TODO()
err := peer.Send(ctx, &dummyMsg{
Content: "handshake"})
if err != nil {
t.Fatal(err)
}
handle := func(ctx context.Context, msg interface{}) error {
return nil
}
return peer.Run(handle)
}
conf := adapters.RandomNodeConfig()
tester := p2ptest.NewProtocolTester(conf.ID, 2, runFunc)
err := tester.TestExchanges(p2ptest.Exchange{
Expects: []p2ptest.Expect{
{
Code: 0,
Msg: &dummyMsg{Content: "handshake"},
Peer: tester.Nodes[0].ID(),
},
},
})
if err != nil {
t.Fatal(err)
}
if testHook.msg == nil || testHook.msg.(*dummyMsg).Content != "handshake" {
t.Fatal("Expected msg to be set, but it is not")
}
if !testHook.send {
t.Fatal("Expected a send message, but it is not")
}
if testHook.peer == nil || testHook.peer.ID() != tester.Nodes[0].ID() {
t.Fatal("Expected peer ID to be set correctly, but it is not")
}
if testHook.size != 11 { //11 is the length of the encoded message
t.Fatalf("Expected size to be %d, but it is %d ", 1, testHook.size)
}
err = tester.TestExchanges(p2ptest.Exchange{
Triggers: []p2ptest.Trigger{
{
Code: 0,
Msg: &dummyMsg{Content: "response"},
Peer: tester.Nodes[1].ID(),
},
},
})
<-testHook.waitC
if err != nil {
t.Fatal(err)
}
if testHook.msg == nil || testHook.msg.(*dummyMsg).Content != "response" {
t.Fatal("Expected msg to be set, but it is not")
}
if testHook.send {
t.Fatal("Expected a send message, but it is not")
}
if testHook.peer == nil || testHook.peer.ID() != tester.Nodes[1].ID() {
t.Fatal("Expected peer ID to be set correctly, but it is not")
}
if testHook.size != 10 { //11 is the length of the encoded message
t.Fatalf("Expected size to be %d, but it is %d ", 1, testHook.size)
}
testHook.err = fmt.Errorf("dummy error")
err = tester.TestExchanges(p2ptest.Exchange{
Triggers: []p2ptest.Trigger{
{
Code: 0,
Msg: &dummyMsg{Content: "response"},
Peer: tester.Nodes[1].ID(),
},
},
})
<-testHook.waitC
time.Sleep(100 * time.Millisecond)
err = tester.TestDisconnected(&p2ptest.Disconnect{Peer: tester.Nodes[1].ID(), Error: testHook.err})
if err != nil {
t.Fatalf("Expected a specific disconnect error, but got different one: %v", err)
}
}
//We need to test that if the hook is not defined, then message infrastructure
//(send,receive) still works
func TestNoHook(t *testing.T) {
//create a test spec
spec := createTestSpec()
//a random node
id := adapters.RandomNodeConfig().ID
//a peer
p := p2p.NewPeer(id, "testPeer", nil)
rw := &dummyRW{}
peer := NewPeer(p, rw, spec)
ctx := context.TODO()
msg := &perBytesMsgSenderPays{Content: "testBalance"}
//send a message
err := peer.Send(ctx, msg)
if err != nil {
t.Fatal(err)
}
//simulate receiving a message
rw.msg = msg
peer.handleIncoming(func(ctx context.Context, msg interface{}) error {
return nil
})
//all should just work and not result in any error
}
func TestProtoHandshakeVersionMismatch(t *testing.T) {
runProtoHandshake(t, &protoHandshake{41, "420"}, errorf(ErrHandshake, errorf(ErrHandler, "(msg code 0): 41 (!= 42)").Error()))
}
func TestProtoHandshakeNetworkIDMismatch(t *testing.T) {
runProtoHandshake(t, &protoHandshake{42, "421"}, errorf(ErrHandshake, errorf(ErrHandler, "(msg code 0): 421 (!= 420)").Error()))
}
func TestProtoHandshakeSuccess(t *testing.T) {
runProtoHandshake(t, &protoHandshake{42, "420"})
}
func moduleHandshakeExchange(id enode.ID, resp uint) []p2ptest.Exchange {
return []p2ptest.Exchange{
{
Expects: []p2ptest.Expect{
{
Code: 1,
Msg: &hs0{42},
Peer: id,
},
},
},
{
Triggers: []p2ptest.Trigger{
{
Code: 1,
Msg: &hs0{resp},
Peer: id,
},
},
},
}
}
func runModuleHandshake(t *testing.T, resp uint, errs ...error) {
pp := p2ptest.NewTestPeerPool()
s := protocolTester(pp)
node := s.Nodes[0]
if err := s.TestExchanges(protoHandshakeExchange(node.ID(), &protoHandshake{42, "420"})...); err != nil {
t.Fatal(err)
}
if err := s.TestExchanges(moduleHandshakeExchange(node.ID(), resp)...); err != nil {
t.Fatal(err)
}
var disconnects []*p2ptest.Disconnect
for i, err := range errs {
disconnects = append(disconnects, &p2ptest.Disconnect{Peer: s.Nodes[i].ID(), Error: err})
}
if err := s.TestDisconnected(disconnects...); err != nil {
t.Fatal(err)
}
}
func TestModuleHandshakeError(t *testing.T) {
runModuleHandshake(t, 43, fmt.Errorf("handshake mismatch remote 43 > local 42"))
}
func TestModuleHandshakeSuccess(t *testing.T) {
runModuleHandshake(t, 42)
}
// testing complex interactions over multiple peers, relaying, dropping
func testMultiPeerSetup(a, b enode.ID) []p2ptest.Exchange {
return []p2ptest.Exchange{
{
Label: "primary handshake",
Expects: []p2ptest.Expect{
{
Code: 0,
Msg: &protoHandshake{42, "420"},
Peer: a,
},
{
Code: 0,
Msg: &protoHandshake{42, "420"},
Peer: b,
},
},
},
{
Label: "module handshake",
Triggers: []p2ptest.Trigger{
{
Code: 0,
Msg: &protoHandshake{42, "420"},
Peer: a,
},
{
Code: 0,
Msg: &protoHandshake{42, "420"},
Peer: b,
},
},
Expects: []p2ptest.Expect{
{
Code: 1,
Msg: &hs0{42},
Peer: a,
},
{
Code: 1,
Msg: &hs0{42},
Peer: b,
},
},
},
{Label: "alternative module handshake", Triggers: []p2ptest.Trigger{{Code: 1, Msg: &hs0{41}, Peer: a},
{Code: 1, Msg: &hs0{41}, Peer: b}}},
{Label: "repeated module handshake", Triggers: []p2ptest.Trigger{{Code: 1, Msg: &hs0{1}, Peer: a}}},
{Label: "receiving repeated module handshake", Expects: []p2ptest.Expect{{Code: 1, Msg: &hs0{43}, Peer: a}}}}
}
func runMultiplePeers(t *testing.T, peer int, errs ...error) {
pp := p2ptest.NewTestPeerPool()
s := protocolTester(pp)
if err := s.TestExchanges(testMultiPeerSetup(s.Nodes[0].ID(), s.Nodes[1].ID())...); err != nil {
t.Fatal(err)
}
// after some exchanges of messages, we can test state changes
// here this is simply demonstrated by the peerPool
// after the handshake negotiations peers must be added to the pool
// time.Sleep(1)
tick := time.NewTicker(10 * time.Millisecond)
timeout := time.NewTimer(1 * time.Second)
WAIT:
for {
select {
case <-tick.C:
if pp.Has(s.Nodes[0].ID()) {
break WAIT
}
case <-timeout.C:
t.Fatal("timeout")
}
}
if !pp.Has(s.Nodes[1].ID()) {
t.Fatalf("missing peer test-1: %v (%v)", pp, s.Nodes)
}
// peer 0 sends kill request for peer with index <peer>
err := s.TestExchanges(p2ptest.Exchange{
Triggers: []p2ptest.Trigger{
{
Code: 2,
Msg: &kill{s.Nodes[peer].ID()},
Peer: s.Nodes[0].ID(),
},
},
})
if err != nil {
t.Fatal(err)
}
// the peer not killed sends a drop request
err = s.TestExchanges(p2ptest.Exchange{
Triggers: []p2ptest.Trigger{
{
Code: 3,
Msg: &drop{},
Peer: s.Nodes[(peer+1)%2].ID(),
},
},
})
if err != nil {
t.Fatal(err)
}
// check the actual discconnect errors on the individual peers
var disconnects []*p2ptest.Disconnect
for i, err := range errs {
disconnects = append(disconnects, &p2ptest.Disconnect{Peer: s.Nodes[i].ID(), Error: err})
}
if err := s.TestDisconnected(disconnects...); err != nil {
t.Fatal(err)
}
// test if disconnected peers have been removed from peerPool
if pp.Has(s.Nodes[peer].ID()) {
t.Fatalf("peer test-%v not dropped: %v (%v)", peer, pp, s.Nodes)
}
}
func XTestMultiplePeersDropSelf(t *testing.T) {
runMultiplePeers(t, 0,
fmt.Errorf("subprotocol error"),
fmt.Errorf("Message handler error: (msg code 3): dropped"),
)
}
func XTestMultiplePeersDropOther(t *testing.T) {
runMultiplePeers(t, 1,
fmt.Errorf("Message handler error: (msg code 3): dropped"),
fmt.Errorf("subprotocol error"),
)
}
//dummy implementation of a MsgReadWriter
//this allows for quick and easy unit tests without
//having to build up the complete protocol
type dummyRW struct {
msg interface{}
size uint32
code uint64
}
func (d *dummyRW) WriteMsg(msg p2p.Msg) error {
return nil
}
func (d *dummyRW) ReadMsg() (p2p.Msg, error) {
enc := bytes.NewReader(d.getDummyMsg())
return p2p.Msg{
Code: d.code,
Size: d.size,
Payload: enc,
ReceivedAt: time.Now(),
}, nil
}
func (d *dummyRW) getDummyMsg() []byte {
r, _ := rlp.EncodeToBytes(d.msg)
var b bytes.Buffer
wmsg := WrappedMsg{
Context: b.Bytes(),
Size: uint32(len(r)),
Payload: r,
}
rr, _ := rlp.EncodeToBytes(wmsg)
d.size = uint32(len(rr))
return rr
}