path: root/p2p/peer_test.go

// Copyright 2014 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 Lesser 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with go-ethereum.  If not, see <http://www.gnu.org/licenses/>.

package p2p

import (
    "errors"
    "fmt"
    "math/rand"
    "net"
    "reflect"
    "testing"
    "time"
)

var discard = Protocol{
    Name:   "discard",
    Length: 1,
    Run: func(p *Peer, rw MsgReadWriter) error {
        for {
            msg, err := rw.ReadMsg()
            if err != nil {
                return err
            }
            fmt.Printf("discarding %d\n", msg.Code)
            if err = msg.Discard(); err != nil {
                return err
            }
        }
    },
}

func testPeer(protos []Protocol) (func(), *conn, *Peer, <-chan DiscReason) {
    fd1, fd2 := net.Pipe()
    c1 := &conn{fd: fd1, transport: newTestTransport(randomID(), fd1)}
    c2 := &conn{fd: fd2, transport: newTestTransport(randomID(), fd2)}
    for _, p := range protos {
        c1.caps = append(c1.caps, p.cap())
        c2.caps = append(c2.caps, p.cap())
    }

    peer := newPeer(c1, protos)
    errc := make(chan DiscReason, 1)
    go func() { errc <- peer.run() }()

    closer := func() { c2.close(errors.New("close func called")) }
    return closer, c2, peer, errc
}

func TestPeerProtoReadMsg(t *testing.T) {
    done := make(chan struct{})
    proto := Protocol{
        Name:   "a",
        Length: 5,
        Run: func(peer *Peer, rw MsgReadWriter) error {
            if err := ExpectMsg(rw, 2, []uint{1}); err != nil {
                t.Error(err)
            }
            if err := ExpectMsg(rw, 3, []uint{2}); err != nil {
                t.Error(err)
            }
            if err := ExpectMsg(rw, 4, []uint{3}); err != nil {
                t.Error(err)
            }
            close(done)
            return nil
        },
    }

    closer, rw, _, errc := testPeer([]Protocol{proto})
    defer closer()

    Send(rw, baseProtocolLength+2, []uint{1})
    Send(rw, baseProtocolLength+3, []uint{2})
    Send(rw, baseProtocolLength+4, []uint{3})

    select {
    case <-done:
    case err := <-errc:
        t.Errorf("peer returned: %v", err)
    case <-time.After(2 * time.Second):
        t.Errorf("receive timeout")
    }
}

func TestPeerProtoEncodeMsg(t *testing.T) {
    proto := Protocol{
        Name:   "a",
        Length: 2,
        Run: func(peer *Peer, rw MsgReadWriter) error {
            if err := SendItems(rw, 2); err == nil {
                t.Error("expected error for out-of-range msg code, got nil")
            }
            if err := SendItems(rw, 1, "foo", "bar"); err != nil {
                t.Errorf("write error: %v", err)
            }
            return nil
        },
    }
    closer, rw, _, _ := testPeer([]Protocol{proto})
    defer closer()

    if err := ExpectMsg(rw, 17, []string{"foo", "bar"}); err != nil {
        t.Error(err)
    }
}

func TestPeerPing(t *testing.T) {
    closer, rw, _, _ := testPeer(nil)
    defer closer()
    if err := SendItems(rw, pingMsg); err != nil {
        t.Fatal(err)
    }
    if err := ExpectMsg(rw, pongMsg, nil); err != nil {
        t.Error(err)
    }
}

func TestPeerDisconnect(t *testing.T) {
    closer, rw, _, disc := testPeer(nil)
    defer closer()
    if err := SendItems(rw, discMsg, DiscQuitting); err != nil {
        t.Fatal(err)
    }
    select {
    case reason := <-disc:
        if reason != DiscRequested {
            t.Errorf("run returned wrong reason: got %v, want %v", reason, DiscRequested)
        }
    case <-time.After(500 * time.Millisecond):
        t.Error("peer did not return")
    }
}

// This test is supposed to verify that Peer can reliably handle
// multiple causes of disconnection occurring at the same time.
func TestPeerDisconnectRace(t *testing.T) {
    maybe := func() bool { return rand.Intn(1) == 1 }

    for i := 0; i < 1000; i++ {
        protoclose := make(chan error)
        protodisc := make(chan DiscReason)
        closer, rw, p, disc := testPeer([]Protocol{
            {
                Name:   "closereq",
                Run:    func(p *Peer, rw MsgReadWriter) error { return <-protoclose },
                Length: 1,
            },
            {
                Name:   "disconnect",
                Run:    func(p *Peer, rw MsgReadWriter) error { p.Disconnect(<-protodisc); return nil },
                Length: 1,
            },
        })

        // Simulate incoming messages.
        go SendItems(rw, baseProtocolLength+1)
        go SendItems(rw, baseProtocolLength+2)
        // Close the network connection.
        go closer()
        // Make protocol "closereq" return.
        protoclose <- errors.New("protocol closed")
        // Make protocol "disconnect" call peer.Disconnect
        protodisc <- DiscAlreadyConnected
        // In some cases, simulate something else calling peer.Disconnect.
        if maybe() {
            go p.Disconnect(DiscInvalidIdentity)
        }
        // In some cases, simulate remote requesting a disconnect.
        if maybe() {
            go SendItems(rw, discMsg, DiscQuitting)
        }

        select {
        case <-disc:
        case <-time.After(2 * time.Second):
            // Peer.run should return quickly. If it doesn't the Peer
            // goroutines are probably deadlocked. Call panic in order to
            // show the stacks.
            panic("Peer.run took to long to return.")
        }
    }
}

func TestNewPeer(t *testing.T) {
    name := "nodename"
    caps := []Cap{{"foo", 2}, {"bar", 3}}
    id := randomID()
    p := NewPeer(id, name, caps)
    if p.ID() != id {
        t.Errorf("ID mismatch: got %v, expected %v", p.ID(), id)
    }
    if p.Name() != name {
        t.Errorf("Name mismatch: got %v, expected %v", p.Name(), name)
    }
    if !reflect.DeepEqual(p.Caps(), caps) {
        t.Errorf("Caps mismatch: got %v, expected %v", p.Caps(), caps)
    }

    p.Disconnect(DiscAlreadyConnected) // Should not hang
}

func TestMatchProtocols(t *testing.T) {
    tests := []struct {
        Remote []Cap
        Local  []Protocol
        Match  map[string]protoRW
    }{
        {
            // No remote capabilities
            Local: []Protocol{{Name: "a"}},
        },
        {
            // No local protocols
            Remote: []Cap{{Name: "a"}},
        },
        {
            // No mutual protocols
            Remote: []Cap{{Name: "a"}},
            Local:  []Protocol{{Name: "b"}},
        },
        {
            // Some matches, some differences
            Remote: []Cap{{Name: "local"}, {Name: "match1"}, {Name: "match2"}},
            Local:  []Protocol{{Name: "match1"}, {Name: "match2"}, {Name: "remote"}},
            Match:  map[string]protoRW{"match1": {Protocol: Protocol{Name: "match1"}}, "match2": {Protocol: Protocol{Name: "match2"}}},
        },
        {
            // Various alphabetical ordering
            Remote: []Cap{{Name: "aa"}, {Name: "ab"}, {Name: "bb"}, {Name: "ba"}},
            Local:  []Protocol{{Name: "ba"}, {Name: "bb"}, {Name: "ab"}, {Name: "aa"}},
            Match:  map[string]protoRW{"aa": {Protocol: Protocol{Name: "aa"}}, "ab": {Protocol: Protocol{Name: "ab"}}, "ba": {Protocol: Protocol{Name: "ba"}}, "bb": {Protocol: Protocol{Name: "bb"}}},
        },
        {
            // No mutual versions
            Remote: []Cap{{Version: 1}},
            Local:  []Protocol{{Version: 2}},
        },
        {
            // Multiple versions, single common
            Remote: []Cap{{Version: 1}, {Version: 2}},
            Local:  []Protocol{{Version: 2}, {Version: 3}},
            Match:  map[string]protoRW{"": {Protocol: Protocol{Version: 2}}},
        },
        {
            // Multiple versions, multiple common
            Remote: []Cap{{Version: 1}, {Version: 2}, {Version: 3}, {Version: 4}},
            Local:  []Protocol{{Version: 2}, {Version: 3}},
            Match:  map[string]protoRW{"": {Protocol: Protocol{Version: 3}}},
        },
        {
            // Various version orderings
            Remote: []Cap{{Version: 4}, {Version: 1}, {Version: 3}, {Version: 2}},
            Local:  []Protocol{{Version: 2}, {Version: 3}, {Version: 1}},
            Match:  map[string]protoRW{"": {Protocol: Protocol{Version: 3}}},
        },
        {
            // Versions overriding sub-protocol lengths
            Remote: []Cap{{Version: 1}, {Version: 2}, {Version: 3}, {Name: "a"}},
            Local:  []Protocol{{Version: 1, Length: 1}, {Version: 2, Length: 2}, {Version: 3, Length: 3}, {Name: "a"}},
            Match:  map[string]protoRW{"": {Protocol: Protocol{Version: 3}}, "a": {Protocol: Protocol{Name: "a"}, offset: 3}},
        },
    }

    for i, tt := range tests {
        result := matchProtocols(tt.Local, tt.Remote, nil)
        if len(result) != len(tt.Match) {
            t.Errorf("test %d: negotiation mismatch: have %v, want %v", i, len(result), len(tt.Match))
            continue
        }
        // Make sure all negotiated protocols are needed and correct
        for name, proto := range result {
            match, ok := tt.Match[name]
            if !ok {
                t.Errorf("test %d, proto '%s': negotiated but shouldn't have", i, name)
                continue
            }
            if proto.Name != match.Name {
                t.Errorf("test %d, proto '%s': name mismatch: have %v, want %v", i, name, proto.Name, match.Name)
            }
            if proto.Version != match.Version {
                t.Errorf("test %d, proto '%s': version mismatch: have %v, want %v", i, name, proto.Version, match.Version)
            }
            if proto.offset-baseProtocolLength != match.offset {
                t.Errorf("test %d, proto '%s': offset mismatch: have %v, want %v", i, name, proto.offset-baseProtocolLength, match.offset)
            }
        }
        // Make sure no protocols missed negotiation
        for name, _ := range tt.Match {
            if _, ok := result[name]; !ok {
                t.Errorf("test %d, proto '%s': not negotiated, should have", i, name)
                continue
            }
        }
    }
}