path: root/p2p/peer_test.go

package p2p

import (
    "bytes"
    "fmt"
    "io/ioutil"
    "net"
    "reflect"
    "sort"
    "testing"
    "time"

    "github.com/ethereum/go-ethereum/p2p/discover"
    "github.com/ethereum/go-ethereum/rlp"
)

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

func testPeer(handshake bool, protos []Protocol) (*frameRW, *Peer, <-chan DiscReason) {
    conn1, conn2 := net.Pipe()
    peer := newPeer(conn1, protos, "name", &discover.NodeID{}, &discover.NodeID{})
    peer.protocolHandshakeEnabled = handshake
    errc := make(chan DiscReason, 1)
    go func() { errc <- peer.run() }()
    return newFrameRW(conn2, msgWriteTimeout), peer, errc
}

func TestPeerProtoReadMsg(t *testing.T) {
    defer testlog(t).detach()

    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
        },
    }

    rw, peer, errc := testPeer(false, []Protocol{proto})
    defer rw.Close()
    peer.startSubprotocols([]Cap{proto.cap()})

    EncodeMsg(rw, baseProtocolLength+2, 1)
    EncodeMsg(rw, baseProtocolLength+3, 2)
    EncodeMsg(rw, baseProtocolLength+4, 3)

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

func TestPeerProtoReadLargeMsg(t *testing.T) {
    defer testlog(t).detach()

    msgsize := uint32(10 * 1024 * 1024)
    done := make(chan struct{})
    proto := Protocol{
        Name:   "a",
        Length: 5,
        Run: func(peer *Peer, rw MsgReadWriter) error {
            msg, err := rw.ReadMsg()
            if err != nil {
                t.Errorf("read error: %v", err)
            }
            if msg.Size != msgsize+4 {
                t.Errorf("incorrect msg.Size, got %d, expected %d", msg.Size, msgsize)
            }
            msg.Discard()
            close(done)
            return nil
        },
    }

    rw, peer, errc := testPeer(false, []Protocol{proto})
    defer rw.Close()
    peer.startSubprotocols([]Cap{proto.cap()})

    EncodeMsg(rw, 18, make([]byte, msgsize))
    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) {
    defer testlog(t).detach()

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

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

func TestPeerWriteForBroadcast(t *testing.T) {
    defer testlog(t).detach()

    rw, peer, peerErr := testPeer(false, []Protocol{discard})
    defer rw.Close()
    peer.startSubprotocols([]Cap{discard.cap()})

    // test write errors
    if err := peer.writeProtoMsg("b", NewMsg(3)); err == nil {
        t.Errorf("expected error for unknown protocol, got nil")
    }
    if err := peer.writeProtoMsg("discard", NewMsg(8)); err == nil {
        t.Errorf("expected error for out-of-range msg code, got nil")
    } else if perr, ok := err.(*peerError); !ok || perr.Code != errInvalidMsgCode {
        t.Errorf("wrong error for out-of-range msg code, got %#v", err)
    }

    // setup for reading the message on the other end
    read := make(chan struct{})
    go func() {
        if err := expectMsg(rw, 16, nil); err != nil {
            t.Error()
        }
        close(read)
    }()

    // test successful write
    if err := peer.writeProtoMsg("discard", NewMsg(0)); err != nil {
        t.Errorf("expect no error for known protocol: %v", err)
    }
    select {
    case <-read:
    case err := <-peerErr:
        t.Fatalf("peer stopped: %v", err)
    }
}

func TestPeerPing(t *testing.T) {
    defer testlog(t).detach()

    rw, _, _ := testPeer(false, nil)
    defer rw.Close()
    if err := EncodeMsg(rw, pingMsg); err != nil {
        t.Fatal(err)
    }
    if err := expectMsg(rw, pongMsg, nil); err != nil {
        t.Error(err)
    }
}

func TestPeerDisconnect(t *testing.T) {
    defer testlog(t).detach()

    rw, _, disc := testPeer(false, nil)
    defer rw.Close()
    if err := EncodeMsg(rw, discMsg, DiscQuitting); err != nil {
        t.Fatal(err)
    }
    if err := expectMsg(rw, discMsg, []interface{}{DiscRequested}); err != nil {
        t.Error(err)
    }
    rw.Close() // make test end faster
    if reason := <-disc; reason != DiscRequested {
        t.Errorf("run returned wrong reason: got %v, want %v", reason, DiscRequested)
    }
}

func TestPeerHandshake(t *testing.T) {
    defer testlog(t).detach()

    // remote has two matching protocols: a and c
    remote := NewPeer(randomID(), "", []Cap{{"a", 1}, {"b", 999}, {"c", 3}})
    remoteID := randomID()
    remote.ourID = &remoteID
    remote.ourName = "remote peer"

    start := make(chan string)
    stop := make(chan struct{})
    run := func(p *Peer, rw MsgReadWriter) error {
        name := rw.(*proto).name
        if name != "a" && name != "c" {
            t.Errorf("protocol %q should not be started", name)
        } else {
            start <- name
        }
        <-stop
        return nil
    }
    protocols := []Protocol{
        {Name: "a", Version: 1, Length: 1, Run: run},
        {Name: "b", Version: 2, Length: 1, Run: run},
        {Name: "c", Version: 3, Length: 1, Run: run},
        {Name: "d", Version: 4, Length: 1, Run: run},
    }
    rw, p, disc := testPeer(true, protocols)
    p.remoteID = remote.ourID
    defer rw.Close()

    // run the handshake
    remoteProtocols := []Protocol{protocols[0], protocols[2]}
    if err := writeProtocolHandshake(rw, "remote peer", remoteID, remoteProtocols); err != nil {
        t.Fatalf("handshake write error: %v", err)
    }
    if err := readProtocolHandshake(remote, rw); err != nil {
        t.Fatalf("handshake read error: %v", err)
    }

    // check that all protocols have been started
    var started []string
    for i := 0; i < 2; i++ {
        select {
        case name := <-start:
            started = append(started, name)
        case <-time.After(100 * time.Millisecond):
        }
    }
    sort.Strings(started)
    if !reflect.DeepEqual(started, []string{"a", "c"}) {
        t.Errorf("wrong protocols started: %v", started)
    }

    // check that metadata has been set
    if p.ID() != remoteID {
        t.Errorf("peer has wrong node ID: got %v, want %v", p.ID(), remoteID)
    }
    if p.Name() != remote.ourName {
        t.Errorf("peer has wrong node name: got %q, want %q", p.Name(), remote.ourName)
    }

    close(stop)
    t.Logf("disc reason: %v", <-disc)
}

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
}

// expectMsg reads a message from r and verifies that its
// code and encoded RLP content match the provided values.
// If content is nil, the payload is discarded and not verified.
func expectMsg(r MsgReader, code uint64, content interface{}) error {
    msg, err := r.ReadMsg()
    if err != nil {
        return err
    }
    if msg.Code != code {
        return fmt.Errorf("message code mismatch: got %d, expected %d", msg.Code, code)
    }
    if content == nil {
        return msg.Discard()
    } else {
        contentEnc, err := rlp.EncodeToBytes(content)
        if err != nil {
            panic("content encode error: " + err.Error())
        }
        // skip over list header in encoded value. this is temporary.
        contentEncR := bytes.NewReader(contentEnc)
        if k, _, err := rlp.NewStream(contentEncR).Kind(); k != rlp.List || err != nil {
            panic("content must encode as RLP list")
        }
        contentEnc = contentEnc[len(contentEnc)-contentEncR.Len():]

        actualContent, err := ioutil.ReadAll(msg.Payload)
        if err != nil {
            return err
        }
        if !bytes.Equal(actualContent, contentEnc) {
            return fmt.Errorf("message payload mismatch:\ngot:  %x\nwant: %x", actualContent, contentEnc)
        }
    }
    return nil
}