peer error introduces more differentiation and verify func is called on peer

- keep missing, mismatch and invalid pubkey errors to errPubkeyInvalid -> DiscInvalidIdentity
- introduce errBlacklistedPeer, errSelfConnection, errConnectedPeer, errRejectedPeer -> DiscUselessPeer
- peer.pubkeyHook -> peer.verifyPeerHook
- peer.verifyPeerHook called on peer by protocol after handshake info set
- peer.Pubkey looks into identity.Pubkey  too (redundant though)

p2p/peer.go

@@ -93,7 +93,7 @@ type Peer struct {
 	ourListenAddr  *peerAddr                   // listen addr of Server, nil if not listening
 	addPeer        func(*peerAddr) error       // tell server about received peers
 	getPeers       func(...[]byte) []*peerAddr // should return the list of all peers
-	pubkeyHook    func(*peerAddr) error       // called at end of handshake to validate pubkey
+	verifyPeerHook func(*Peer) error           // called at end of handshake to validate peer
 }
 
 // NewPeer returns a peer for testing purposes.
@@ -152,13 +152,14 @@ func (self *Peer) Hash() []byte {
 func (self *Peer) Pubkey() (pubkey []byte) {
 	self.infolock.Lock()
 	defer self.infolock.Unlock()
-	if self.dialAddr != nil {
+	switch {
+	case self.identity != nil:
+		pubkey = self.identity.Pubkey()
+	case self.dialAddr != nil:
 		pubkey = self.dialAddr.Pubkey
-	} else {
-		if self.listenAddr != nil {
+	case self.listenAddr != nil:
 		pubkey = self.listenAddr.Pubkey
 	}
-	}
 	return
 }
 

p2p/peer_error.go

@@ -14,7 +14,11 @@ const (
 	errP2PVersionMismatch
 	errPubkeyMissing
 	errPubkeyInvalid
-	errPubkeyForbidden
+	errPubkeyMismatch
+	errBlacklistedPeer
+	errSelfConnection
+	errConnectedPeer
+	errRejectedPeer
 	errProtocolBreach
 	errPingTimeout
 	errInvalidNetworkId
@@ -31,7 +35,11 @@ var errorToString = map[int]string{
 	errP2PVersionMismatch:     "P2P Version Mismatch",
 	errPubkeyMissing:          "Public key missing",
 	errPubkeyInvalid:          "Public key invalid",
-	errPubkeyForbidden:        "Public key forbidden",
+	errPubkeyMismatch:         "Public key mismatch",
+	errBlacklistedPeer:        "Blacklisted peer",
+	errSelfConnection:         "Self connection",
+	errConnectedPeer:          "Connected peer",
+	errRejectedPeer:           "Rejected peer",
 	errProtocolBreach:         "Protocol Breach",
 	errPingTimeout:            "Ping timeout",
 	errInvalidNetworkId:       "Invalid network id",
@@ -117,9 +125,9 @@ func discReasonForError(err error) DiscReason {
 	switch peerError.Code {
 	case errP2PVersionMismatch:
 		return DiscIncompatibleVersion
-	case errPubkeyMissing, errPubkeyInvalid:
+	case errPubkeyMissing, errPubkeyMismatch, errPubkeyInvalid:
 		return DiscInvalidIdentity
-	case errPubkeyForbidden:
+	case errBlacklistedPeer, errSelfConnection, errConnectedPeer, errRejectedPeer:
 		return DiscUselessPeer
 	case errInvalidMsgCode, errMagicTokenMismatch, errProtocolBreach:
 		return DiscProtocolError

p2p/peer_test.go

@@ -34,7 +34,7 @@ func testPeer(protos []Protocol) (net.Conn, *Peer, <-chan error) {
 	peer.init(conn1)
 	peer.protocols = protos
 	peer.ourID = &peerId{}
-	peer.pubkeyHook = func(*peerAddr) error { return nil }
+	peer.verifyPeerHook = func(*Peer) error { return nil }
 	errc := make(chan error, 1)
 	go func() {
 		_, err := peer.loop()

p2p/protocol.go

@@ -249,13 +249,9 @@ func (bp *baseProtocol) readHandshake() error {
 		// verify that the peer we wanted to connect to
 		// actually holds the target public key.
 		if da.Pubkey != nil && !bytes.Equal(da.Pubkey, hs.NodeID) {
-			return newPeerError(errPubkeyForbidden, "dial address pubkey mismatch")
+			return newPeerError(errPubkeyMismatch, "dial address pubkey mismatch: %x vs %x", da.Pubkey, hs.NodeID)
 		}
 	}
-	pa := newPeerAddr(bp.peer.conn.RemoteAddr(), hs.NodeID)
-	if err := bp.peer.pubkeyHook(pa); err != nil {
-		return newPeerError(errPubkeyForbidden, "%v", err)
-	}
 	// TODO: remove Caps with empty name
 	var addr *peerAddr
 	if hs.ListenPort != 0 {
@@ -263,6 +259,9 @@ func (bp *baseProtocol) readHandshake() error {
 		addr.Port = hs.ListenPort
 	}
 	bp.peer.setHandshakeInfo(&hs, addr, hs.Caps)
+	if err := bp.peer.verifyPeerHook(bp.peer); err != nil {
+		return err
+	}
 	bp.peer.startSubprotocols(hs.Caps)
 	return nil
 }

p2p/protocol_test.go

@@ -29,7 +29,7 @@ func (self *peerId) Pubkey() (pubkey []byte) {
 
 func newTestPeer() (peer *Peer) {
 	peer = NewPeer(&peerId{}, []Cap{})
-	peer.pubkeyHook = func(*peerAddr) error { return nil }
+	peer.verifyPeerHook = func(*Peer) error { return nil }
 	peer.ourID = &peerId{}
 	peer.listenAddr = &peerAddr{}
 	peer.getPeers = func(...[]byte) []*peerAddr { return nil }
@@ -110,7 +110,7 @@ func TestBaseProtocolPeers(t *testing.T) {
 func TestBaseProtocolDisconnect(t *testing.T) {
 	peer := NewPeer(&peerId{}, nil)
 	peer.ourID = &peerId{}
-	peer.pubkeyHook = func(*peerAddr) error { return nil }
+	peer.verifyPeerHook = func(*Peer) error { return nil }
 
 	rw1, rw2 := MsgPipe()
 	done := make(chan struct{})

p2p/server.go

@@ -189,7 +189,7 @@ func (srv *Server) connect(p *Peer, conn net.Conn) {
 	p.ourID = srv.Identity
 	p.addPeer = srv.AddPeer
 	p.getPeers = srv.GetPeers
-	p.pubkeyHook = srv.verifyPeer
+	p.verifyPeerHook = srv.verifyPeer
 	p.runBaseProtocol = true
 	p.protocols = srv.Protocols
 
@@ -427,20 +427,21 @@ func (srv *Server) removePeer(peer *Peer) {
 	srv.peerSlots <- peer.slot
 }
 
-func (srv *Server) verifyPeer(addr *peerAddr) error {
-	if srv.Blacklist.Exists(addr.Pubkey) {
-		return errors.New("blacklisted")
+func (srv *Server) verifyPeer(peer *Peer) error {
+	pubkey := peer.Pubkey()
+	if srv.Blacklist.Exists(pubkey) {
+		return newPeerError(errBlacklistedPeer, "")
 	}
-	if bytes.Equal(srv.Identity.Pubkey()[1:], addr.Pubkey) {
-		return newPeerError(errPubkeyForbidden, "not allowed to connect to srv")
+	if bytes.Equal(srv.Identity.Pubkey()[1:], pubkey) {
+		return newPeerError(errSelfConnection, "")
 	}
 	srv.lock.RLock()
 	defer srv.lock.RUnlock()
 	for _, peer := range srv.peers {
 		if peer != nil {
 			id := peer.Identity()
-			if id != nil && bytes.Equal(id.Pubkey(), addr.Pubkey) {
-				return errors.New("already connected")
+			if id != nil && bytes.Equal(id.Pubkey(), pubkey) {
+				return newPeerError(errConnectedPeer, "")
 			}
 		}
 	}