p2p: fix disconnect at capacity

With the introduction of static/trusted nodes, the peer count
can go above MaxPeers. Update the capacity check to handle this.
While here, decouple the trusted nodes check from the handshake
by passing a function instead.
This commit is contained in:
Felix Lange 2015-05-08 15:54:35 +02:00
parent 23454dcfcb
commit 914e57e49b
4 changed files with 46 additions and 33 deletions

View File

@ -65,26 +65,26 @@ type protoHandshake struct {
ID discover.NodeID ID discover.NodeID
} }
// setupConn starts a protocol session on the given connection. // setupConn starts a protocol session on the given connection. It
// It runs the encryption handshake and the protocol handshake. // runs the encryption handshake and the protocol handshake. If dial
// If dial is non-nil, the connection the local node is the initiator. // is non-nil, the connection the local node is the initiator. If
// If atcap is true, the connection will be disconnected with DiscTooManyPeers // keepconn returns false, the connection will be disconnected with
// after the key exchange. // DiscTooManyPeers after the key exchange.
func setupConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node, atcap bool, trusted map[discover.NodeID]bool) (*conn, error) { func setupConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node, keepconn func(discover.NodeID) bool) (*conn, error) {
if dial == nil { if dial == nil {
return setupInboundConn(fd, prv, our, atcap, trusted) return setupInboundConn(fd, prv, our, keepconn)
} else { } else {
return setupOutboundConn(fd, prv, our, dial, atcap, trusted) return setupOutboundConn(fd, prv, our, dial, keepconn)
} }
} }
func setupInboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, atcap bool, trusted map[discover.NodeID]bool) (*conn, error) { func setupInboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, keepconn func(discover.NodeID) bool) (*conn, error) {
secrets, err := receiverEncHandshake(fd, prv, nil) secrets, err := receiverEncHandshake(fd, prv, nil)
if err != nil { if err != nil {
return nil, fmt.Errorf("encryption handshake failed: %v", err) return nil, fmt.Errorf("encryption handshake failed: %v", err)
} }
rw := newRlpxFrameRW(fd, secrets) rw := newRlpxFrameRW(fd, secrets)
if atcap && !trusted[secrets.RemoteID] { if !keepconn(secrets.RemoteID) {
SendItems(rw, discMsg, DiscTooManyPeers) SendItems(rw, discMsg, DiscTooManyPeers)
return nil, errors.New("we have too many peers") return nil, errors.New("we have too many peers")
} }
@ -99,13 +99,13 @@ func setupInboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, a
return &conn{rw, rhs}, nil return &conn{rw, rhs}, nil
} }
func setupOutboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node, atcap bool, trusted map[discover.NodeID]bool) (*conn, error) { func setupOutboundConn(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node, keepconn func(discover.NodeID) bool) (*conn, error) {
secrets, err := initiatorEncHandshake(fd, prv, dial.ID, nil) secrets, err := initiatorEncHandshake(fd, prv, dial.ID, nil)
if err != nil { if err != nil {
return nil, fmt.Errorf("encryption handshake failed: %v", err) return nil, fmt.Errorf("encryption handshake failed: %v", err)
} }
rw := newRlpxFrameRW(fd, secrets) rw := newRlpxFrameRW(fd, secrets)
if atcap && !trusted[secrets.RemoteID] { if !keepconn(secrets.RemoteID) {
SendItems(rw, discMsg, DiscTooManyPeers) SendItems(rw, discMsg, DiscTooManyPeers)
return nil, errors.New("we have too many peers") return nil, errors.New("we have too many peers")
} }

View File

@ -141,9 +141,10 @@ func TestSetupConn(t *testing.T) {
fd0, fd1 := net.Pipe() fd0, fd1 := net.Pipe()
done := make(chan struct{}) done := make(chan struct{})
keepalways := func(discover.NodeID) bool { return true }
go func() { go func() {
defer close(done) defer close(done)
conn0, err := setupConn(fd0, prv0, hs0, node1, false, nil) conn0, err := setupConn(fd0, prv0, hs0, node1, keepalways)
if err != nil { if err != nil {
t.Errorf("outbound side error: %v", err) t.Errorf("outbound side error: %v", err)
return return
@ -156,7 +157,7 @@ func TestSetupConn(t *testing.T) {
} }
}() }()
conn1, err := setupConn(fd1, prv1, hs1, nil, false, nil) conn1, err := setupConn(fd1, prv1, hs1, nil, keepalways)
if err != nil { if err != nil {
t.Fatalf("inbound side error: %v", err) t.Fatalf("inbound side error: %v", err)
} }

View File

@ -126,7 +126,7 @@ type Server struct {
peerWG sync.WaitGroup // active peer goroutines peerWG sync.WaitGroup // active peer goroutines
} }
type setupFunc func(net.Conn, *ecdsa.PrivateKey, *protoHandshake, *discover.Node, bool, map[discover.NodeID]bool) (*conn, error) type setupFunc func(net.Conn, *ecdsa.PrivateKey, *protoHandshake, *discover.Node, func(discover.NodeID) bool) (*conn, error)
type newPeerHook func(*Peer) type newPeerHook func(*Peer)
// Peers returns all connected peers. // Peers returns all connected peers.
@ -506,17 +506,7 @@ func (srv *Server) startPeer(fd net.Conn, dest *discover.Node) {
// the callers of startPeer added the peer to the wait group already. // the callers of startPeer added the peer to the wait group already.
fd.SetDeadline(time.Now().Add(handshakeTimeout)) fd.SetDeadline(time.Now().Add(handshakeTimeout))
// Check capacity, but override for static nodes conn, err := srv.setupFunc(fd, srv.PrivateKey, srv.ourHandshake, dest, srv.keepconn)
srv.lock.RLock()
atcap := len(srv.peers) == srv.MaxPeers
if dest != nil {
if _, ok := srv.staticNodes[dest.ID]; ok {
atcap = false
}
}
srv.lock.RUnlock()
conn, err := srv.setupFunc(fd, srv.PrivateKey, srv.ourHandshake, dest, atcap, srv.trustedNodes)
if err != nil { if err != nil {
fd.Close() fd.Close()
glog.V(logger.Debug).Infof("Handshake with %v failed: %v", fd.RemoteAddr(), err) glog.V(logger.Debug).Infof("Handshake with %v failed: %v", fd.RemoteAddr(), err)
@ -539,6 +529,21 @@ func (srv *Server) startPeer(fd net.Conn, dest *discover.Node) {
go srv.runPeer(p) go srv.runPeer(p)
} }
// preflight checks whether a connection should be kept. it runs
// after the encryption handshake, as soon as the remote identity is
// known.
func (srv *Server) keepconn(id discover.NodeID) bool {
srv.lock.RLock()
defer srv.lock.RUnlock()
if _, ok := srv.staticNodes[id]; ok {
return true // static nodes are always allowed
}
if _, ok := srv.trustedNodes[id]; ok {
return true // trusted nodes are always allowed
}
return len(srv.peers) < srv.MaxPeers
}
func (srv *Server) runPeer(p *Peer) { func (srv *Server) runPeer(p *Peer) {
glog.V(logger.Debug).Infof("Added %v\n", p) glog.V(logger.Debug).Infof("Added %v\n", p)
srvjslog.LogJson(&logger.P2PConnected{ srvjslog.LogJson(&logger.P2PConnected{

View File

@ -22,8 +22,11 @@ func startTestServer(t *testing.T, pf newPeerHook) *Server {
ListenAddr: "127.0.0.1:0", ListenAddr: "127.0.0.1:0",
PrivateKey: newkey(), PrivateKey: newkey(),
newPeerHook: pf, newPeerHook: pf,
setupFunc: func(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node, atcap bool, trusted map[discover.NodeID]bool) (*conn, error) { setupFunc: func(fd net.Conn, prv *ecdsa.PrivateKey, our *protoHandshake, dial *discover.Node, keepconn func(discover.NodeID) bool) (*conn, error) {
id := randomID() id := randomID()
if !keepconn(id) {
return nil, DiscAlreadyConnected
}
rw := newRlpxFrameRW(fd, secrets{ rw := newRlpxFrameRW(fd, secrets{
MAC: zero16, MAC: zero16,
AES: zero16, AES: zero16,
@ -200,7 +203,7 @@ func TestServerDisconnectAtCap(t *testing.T) {
// Run the handshakes just like a real peer would. // Run the handshakes just like a real peer would.
key := newkey() key := newkey()
hs := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)} hs := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)}
_, err = setupConn(conn, key, hs, srv.Self(), false, srv.trustedNodes) _, err = setupConn(conn, key, hs, srv.Self(), keepalways)
if i == nconns-1 { if i == nconns-1 {
// When handling the last connection, the server should // When handling the last connection, the server should
// disconnect immediately instead of running the protocol // disconnect immediately instead of running the protocol
@ -250,7 +253,7 @@ func TestServerStaticPeers(t *testing.T) {
// Run the handshakes just like a real peer would, and wait for completion // Run the handshakes just like a real peer would, and wait for completion
key := newkey() key := newkey()
shake := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)} shake := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)}
if _, err = setupConn(conn, key, shake, server.Self(), false, server.trustedNodes); err != nil { if _, err = setupConn(conn, key, shake, server.Self(), keepalways); err != nil {
t.Fatalf("conn %d: unexpected error: %v", i, err) t.Fatalf("conn %d: unexpected error: %v", i, err)
} }
<-started <-started
@ -344,7 +347,7 @@ func TestServerTrustedPeers(t *testing.T) {
// Run the handshakes just like a real peer would, and wait for completion // Run the handshakes just like a real peer would, and wait for completion
key := newkey() key := newkey()
shake := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)} shake := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)}
if _, err = setupConn(conn, key, shake, server.Self(), false, server.trustedNodes); err != nil { if _, err = setupConn(conn, key, shake, server.Self(), keepalways); err != nil {
t.Fatalf("conn %d: unexpected error: %v", i, err) t.Fatalf("conn %d: unexpected error: %v", i, err)
} }
<-started <-started
@ -357,7 +360,7 @@ func TestServerTrustedPeers(t *testing.T) {
defer conn.Close() defer conn.Close()
shake := &protoHandshake{Version: baseProtocolVersion, ID: trusted.ID} shake := &protoHandshake{Version: baseProtocolVersion, ID: trusted.ID}
if _, err = setupConn(conn, key, shake, server.Self(), false, server.trustedNodes); err != nil { if _, err = setupConn(conn, key, shake, server.Self(), keepalways); err != nil {
t.Fatalf("trusted node: unexpected error: %v", err) t.Fatalf("trusted node: unexpected error: %v", err)
} }
select { select {
@ -472,7 +475,7 @@ func TestServerMaxPendingAccepts(t *testing.T) {
go func() { go func() {
key := newkey() key := newkey()
shake := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)} shake := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)}
if _, err := setupConn(conns[1], key, shake, server.Self(), false, server.trustedNodes); err != nil { if _, err := setupConn(conns[1], key, shake, server.Self(), keepalways); err != nil {
t.Fatalf("failed to run handshake: %v", err) t.Fatalf("failed to run handshake: %v", err)
} }
}() }()
@ -486,7 +489,7 @@ func TestServerMaxPendingAccepts(t *testing.T) {
go func() { go func() {
key := newkey() key := newkey()
shake := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)} shake := &protoHandshake{Version: baseProtocolVersion, ID: discover.PubkeyID(&key.PublicKey)}
if _, err := setupConn(conns[0], key, shake, server.Self(), false, server.trustedNodes); err != nil { if _, err := setupConn(conns[0], key, shake, server.Self(), keepalways); err != nil {
t.Fatalf("failed to run handshake: %v", err) t.Fatalf("failed to run handshake: %v", err)
} }
}() }()
@ -513,3 +516,7 @@ func randomID() (id discover.NodeID) {
} }
return id return id
} }
func keepalways(id discover.NodeID) bool {
return true
}