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-rw-r--r--p2p/peer.go476
1 files changed, 432 insertions, 44 deletions
diff --git a/p2p/peer.go b/p2p/peer.go
index 34b6152a3..238d3d9c9 100644
--- a/p2p/peer.go
+++ b/p2p/peer.go
@@ -1,66 +1,454 @@
package p2p
import (
+ "bufio"
+ "bytes"
"fmt"
+ "io"
+ "io/ioutil"
"net"
- "strconv"
+ "sort"
+ "sync"
+ "time"
+
+ "github.com/ethereum/go-ethereum/event"
+ "github.com/ethereum/go-ethereum/logger"
)
+// peerAddr is the structure of a peer list element.
+// It is also a valid net.Addr.
+type peerAddr struct {
+ IP net.IP
+ Port uint64
+ Pubkey []byte // optional
+}
+
+func newPeerAddr(addr net.Addr, pubkey []byte) *peerAddr {
+ n := addr.Network()
+ if n != "tcp" && n != "tcp4" && n != "tcp6" {
+ // for testing with non-TCP
+ return &peerAddr{net.ParseIP("127.0.0.1"), 30303, pubkey}
+ }
+ ta := addr.(*net.TCPAddr)
+ return &peerAddr{ta.IP, uint64(ta.Port), pubkey}
+}
+
+func (d peerAddr) Network() string {
+ if d.IP.To4() != nil {
+ return "tcp4"
+ } else {
+ return "tcp6"
+ }
+}
+
+func (d peerAddr) String() string {
+ return fmt.Sprintf("%v:%d", d.IP, d.Port)
+}
+
+func (d peerAddr) RlpData() interface{} {
+ return []interface{}{d.IP, d.Port, d.Pubkey}
+}
+
+// Peer represents a remote peer.
type Peer struct {
- Inbound bool // inbound (via listener) or outbound (via dialout)
- Address net.Addr
- Host []byte
- Port uint16
- Pubkey []byte
- Id string
- Caps []string
- peerErrorChan chan error
- messenger *messenger
- peerErrorHandler *PeerErrorHandler
- server *Server
-}
-
-func NewPeer(conn net.Conn, address net.Addr, inbound bool, server *Server) *Peer {
- peerErrorChan := NewPeerErrorChannel()
- host, port, _ := net.SplitHostPort(address.String())
- intport, _ := strconv.Atoi(port)
- peer := &Peer{
- Inbound: inbound,
- Address: address,
- Port: uint16(intport),
- Host: net.ParseIP(host),
- peerErrorChan: peerErrorChan,
- server: server,
- }
- peer.messenger = newMessenger(peer, conn, peerErrorChan, server.Handlers())
- peer.peerErrorHandler = NewPeerErrorHandler(address, server.PeerDisconnect(), peerErrorChan)
+ // Peers have all the log methods.
+ // Use them to display messages related to the peer.
+ *logger.Logger
+
+ infolock sync.Mutex
+ identity ClientIdentity
+ caps []Cap
+ listenAddr *peerAddr // what remote peer is listening on
+ dialAddr *peerAddr // non-nil if dialing
+
+ // The mutex protects the connection
+ // so only one protocol can write at a time.
+ writeMu sync.Mutex
+ conn net.Conn
+ bufconn *bufio.ReadWriter
+
+ // These fields maintain the running protocols.
+ protocols []Protocol
+ runBaseProtocol bool // for testing
+
+ runlock sync.RWMutex // protects running
+ running map[string]*proto
+
+ protoWG sync.WaitGroup
+ protoErr chan error
+ closed chan struct{}
+ disc chan DiscReason
+
+ activity event.TypeMux // for activity events
+
+ slot int // index into Server peer list
+
+ // These fields are kept so base protocol can access them.
+ // TODO: this should be one or more interfaces
+ ourID ClientIdentity // client id of the Server
+ ourListenAddr *peerAddr // listen addr of Server, nil if not listening
+ newPeerAddr chan<- *peerAddr // tell server about received peers
+ otherPeers func() []*Peer // should return the list of all peers
+ pubkeyHook func(*peerAddr) error // called at end of handshake to validate pubkey
+}
+
+// NewPeer returns a peer for testing purposes.
+func NewPeer(id ClientIdentity, caps []Cap) *Peer {
+ conn, _ := net.Pipe()
+ peer := newPeer(conn, nil, nil)
+ peer.setHandshakeInfo(id, nil, caps)
return peer
}
-func (self *Peer) String() string {
- var kind string
- if self.Inbound {
- kind = "inbound"
- } else {
+func newServerPeer(server *Server, conn net.Conn, dialAddr *peerAddr) *Peer {
+ p := newPeer(conn, server.Protocols, dialAddr)
+ p.ourID = server.Identity
+ p.newPeerAddr = server.peerConnect
+ p.otherPeers = server.Peers
+ p.pubkeyHook = server.verifyPeer
+ p.runBaseProtocol = true
+
+ // laddr can be updated concurrently by NAT traversal.
+ // newServerPeer must be called with the server lock held.
+ if server.laddr != nil {
+ p.ourListenAddr = newPeerAddr(server.laddr, server.Identity.Pubkey())
+ }
+ return p
+}
+
+func newPeer(conn net.Conn, protocols []Protocol, dialAddr *peerAddr) *Peer {
+ p := &Peer{
+ Logger: logger.NewLogger("P2P " + conn.RemoteAddr().String()),
+ conn: conn,
+ dialAddr: dialAddr,
+ bufconn: bufio.NewReadWriter(bufio.NewReader(conn), bufio.NewWriter(conn)),
+ protocols: protocols,
+ running: make(map[string]*proto),
+ disc: make(chan DiscReason),
+ protoErr: make(chan error),
+ closed: make(chan struct{}),
+ }
+ return p
+}
+
+// Identity returns the client identity of the remote peer. The
+// identity can be nil if the peer has not yet completed the
+// handshake.
+func (p *Peer) Identity() ClientIdentity {
+ p.infolock.Lock()
+ defer p.infolock.Unlock()
+ return p.identity
+}
+
+// Caps returns the capabilities (supported subprotocols) of the remote peer.
+func (p *Peer) Caps() []Cap {
+ p.infolock.Lock()
+ defer p.infolock.Unlock()
+ return p.caps
+}
+
+func (p *Peer) setHandshakeInfo(id ClientIdentity, laddr *peerAddr, caps []Cap) {
+ p.infolock.Lock()
+ p.identity = id
+ p.listenAddr = laddr
+ p.caps = caps
+ p.infolock.Unlock()
+}
+
+// RemoteAddr returns the remote address of the network connection.
+func (p *Peer) RemoteAddr() net.Addr {
+ return p.conn.RemoteAddr()
+}
+
+// LocalAddr returns the local address of the network connection.
+func (p *Peer) LocalAddr() net.Addr {
+ return p.conn.LocalAddr()
+}
+
+// Disconnect terminates the peer connection with the given reason.
+// It returns immediately and does not wait until the connection is closed.
+func (p *Peer) Disconnect(reason DiscReason) {
+ select {
+ case p.disc <- reason:
+ case <-p.closed:
+ }
+}
+
+// String implements fmt.Stringer.
+func (p *Peer) String() string {
+ kind := "inbound"
+ p.infolock.Lock()
+ if p.dialAddr != nil {
kind = "outbound"
}
- return fmt.Sprintf("%v:%v (%s) v%v %v", self.Host, self.Port, kind, self.Id, self.Caps)
+ p.infolock.Unlock()
+ return fmt.Sprintf("Peer(%p %v %s)", p, p.conn.RemoteAddr(), kind)
+}
+
+const (
+ // maximum amount of time allowed for reading a message
+ msgReadTimeout = 5 * time.Second
+ // maximum amount of time allowed for writing a message
+ msgWriteTimeout = 5 * time.Second
+ // messages smaller than this many bytes will be read at
+ // once before passing them to a protocol.
+ wholePayloadSize = 64 * 1024
+)
+
+var (
+ inactivityTimeout = 2 * time.Second
+ disconnectGracePeriod = 2 * time.Second
+)
+
+func (p *Peer) loop() (reason DiscReason, err error) {
+ defer p.activity.Stop()
+ defer p.closeProtocols()
+ defer close(p.closed)
+ defer p.conn.Close()
+
+ // read loop
+ readMsg := make(chan Msg)
+ readErr := make(chan error)
+ readNext := make(chan bool, 1)
+ protoDone := make(chan struct{}, 1)
+ go p.readLoop(readMsg, readErr, readNext)
+ readNext <- true
+
+ if p.runBaseProtocol {
+ p.startBaseProtocol()
+ }
+
+loop:
+ for {
+ select {
+ case msg := <-readMsg:
+ // a new message has arrived.
+ var wait bool
+ if wait, err = p.dispatch(msg, protoDone); err != nil {
+ p.Errorf("msg dispatch error: %v\n", err)
+ reason = discReasonForError(err)
+ break loop
+ }
+ if !wait {
+ // Msg has already been read completely, continue with next message.
+ readNext <- true
+ }
+ p.activity.Post(time.Now())
+ case <-protoDone:
+ // protocol has consumed the message payload,
+ // we can continue reading from the socket.
+ readNext <- true
+
+ case err := <-readErr:
+ // read failed. there is no need to run the
+ // polite disconnect sequence because the connection
+ // is probably dead anyway.
+ // TODO: handle write errors as well
+ return DiscNetworkError, err
+ case err = <-p.protoErr:
+ reason = discReasonForError(err)
+ break loop
+ case reason = <-p.disc:
+ break loop
+ }
+ }
+
+ // wait for read loop to return.
+ close(readNext)
+ <-readErr
+ // tell the remote end to disconnect
+ done := make(chan struct{})
+ go func() {
+ p.conn.SetDeadline(time.Now().Add(disconnectGracePeriod))
+ p.writeMsg(NewMsg(discMsg, reason), disconnectGracePeriod)
+ io.Copy(ioutil.Discard, p.conn)
+ close(done)
+ }()
+ select {
+ case <-done:
+ case <-time.After(disconnectGracePeriod):
+ }
+ return reason, err
+}
+
+func (p *Peer) readLoop(msgc chan<- Msg, errc chan<- error, unblock <-chan bool) {
+ for _ = range unblock {
+ p.conn.SetReadDeadline(time.Now().Add(msgReadTimeout))
+ if msg, err := readMsg(p.bufconn); err != nil {
+ errc <- err
+ } else {
+ msgc <- msg
+ }
+ }
+ close(errc)
+}
+
+func (p *Peer) dispatch(msg Msg, protoDone chan struct{}) (wait bool, err error) {
+ proto, err := p.getProto(msg.Code)
+ if err != nil {
+ return false, err
+ }
+ if msg.Size <= wholePayloadSize {
+ // optimization: msg is small enough, read all
+ // of it and move on to the next message
+ buf, err := ioutil.ReadAll(msg.Payload)
+ if err != nil {
+ return false, err
+ }
+ msg.Payload = bytes.NewReader(buf)
+ proto.in <- msg
+ } else {
+ wait = true
+ pr := &eofSignal{msg.Payload, protoDone}
+ msg.Payload = pr
+ proto.in <- msg
+ }
+ return wait, nil
+}
+
+func (p *Peer) startBaseProtocol() {
+ p.runlock.Lock()
+ defer p.runlock.Unlock()
+ p.running[""] = p.startProto(0, Protocol{
+ Length: baseProtocolLength,
+ Run: runBaseProtocol,
+ })
+}
+
+// startProtocols starts matching named subprotocols.
+func (p *Peer) startSubprotocols(caps []Cap) {
+ sort.Sort(capsByName(caps))
+
+ p.runlock.Lock()
+ defer p.runlock.Unlock()
+ offset := baseProtocolLength
+outer:
+ for _, cap := range caps {
+ for _, proto := range p.protocols {
+ if proto.Name == cap.Name &&
+ proto.Version == cap.Version &&
+ p.running[cap.Name] == nil {
+ p.running[cap.Name] = p.startProto(offset, proto)
+ offset += proto.Length
+ continue outer
+ }
+ }
+ }
+}
+
+func (p *Peer) startProto(offset uint64, impl Protocol) *proto {
+ rw := &proto{
+ in: make(chan Msg),
+ offset: offset,
+ maxcode: impl.Length,
+ peer: p,
+ }
+ p.protoWG.Add(1)
+ go func() {
+ err := impl.Run(p, rw)
+ if err == nil {
+ p.Infof("protocol %q returned", impl.Name)
+ err = newPeerError(errMisc, "protocol returned")
+ } else {
+ p.Errorf("protocol %q error: %v\n", impl.Name, err)
+ }
+ select {
+ case p.protoErr <- err:
+ case <-p.closed:
+ }
+ p.protoWG.Done()
+ }()
+ return rw
+}
+
+// getProto finds the protocol responsible for handling
+// the given message code.
+func (p *Peer) getProto(code uint64) (*proto, error) {
+ p.runlock.RLock()
+ defer p.runlock.RUnlock()
+ for _, proto := range p.running {
+ if code >= proto.offset && code < proto.offset+proto.maxcode {
+ return proto, nil
+ }
+ }
+ return nil, newPeerError(errInvalidMsgCode, "%d", code)
+}
+
+func (p *Peer) closeProtocols() {
+ p.runlock.RLock()
+ for _, p := range p.running {
+ close(p.in)
+ }
+ p.runlock.RUnlock()
+ p.protoWG.Wait()
+}
+
+// writeProtoMsg sends the given message on behalf of the given named protocol.
+func (p *Peer) writeProtoMsg(protoName string, msg Msg) error {
+ p.runlock.RLock()
+ proto, ok := p.running[protoName]
+ p.runlock.RUnlock()
+ if !ok {
+ return fmt.Errorf("protocol %s not handled by peer", protoName)
+ }
+ if msg.Code >= proto.maxcode {
+ return newPeerError(errInvalidMsgCode, "code %x is out of range for protocol %q", msg.Code, protoName)
+ }
+ msg.Code += proto.offset
+ return p.writeMsg(msg, msgWriteTimeout)
+}
+
+// writeMsg writes a message to the connection.
+func (p *Peer) writeMsg(msg Msg, timeout time.Duration) error {
+ p.writeMu.Lock()
+ defer p.writeMu.Unlock()
+ p.conn.SetWriteDeadline(time.Now().Add(timeout))
+ if err := writeMsg(p.bufconn, msg); err != nil {
+ return newPeerError(errWrite, "%v", err)
+ }
+ return p.bufconn.Flush()
+}
+
+type proto struct {
+ name string
+ in chan Msg
+ maxcode, offset uint64
+ peer *Peer
+}
+
+func (rw *proto) WriteMsg(msg Msg) error {
+ if msg.Code >= rw.maxcode {
+ return newPeerError(errInvalidMsgCode, "not handled")
+ }
+ msg.Code += rw.offset
+ return rw.peer.writeMsg(msg, msgWriteTimeout)
}
-func (self *Peer) Write(protocol string, msg Msg) error {
- return self.messenger.writeProtoMsg(protocol, msg)
+func (rw *proto) EncodeMsg(code uint64, data ...interface{}) error {
+ return rw.WriteMsg(NewMsg(code, data))
}
-func (self *Peer) Start() {
- self.peerErrorHandler.Start()
- self.messenger.Start()
+func (rw *proto) ReadMsg() (Msg, error) {
+ msg, ok := <-rw.in
+ if !ok {
+ return msg, io.EOF
+ }
+ msg.Code -= rw.offset
+ return msg, nil
}
-func (self *Peer) Stop() {
- self.peerErrorHandler.Stop()
- self.messenger.Stop()
+// eofSignal wraps a reader with eof signaling.
+// the eof channel is closed when the wrapped reader
+// reaches EOF.
+type eofSignal struct {
+ wrapped io.Reader
+ eof chan<- struct{}
}
-func (p *Peer) Encode() []interface{} {
- return []interface{}{p.Host, p.Port, p.Pubkey}
+func (r *eofSignal) Read(buf []byte) (int, error) {
+ n, err := r.wrapped.Read(buf)
+ if err != nil {
+ r.eof <- struct{}{} // tell Peer that msg has been consumed
+ }
+ return n, err
}