diff --git a/internal/web3ext/web3ext.go b/internal/web3ext/web3ext.go index c2e0cd3f5d..000e3728de 100644 --- a/internal/web3ext/web3ext.go +++ b/internal/web3ext/web3ext.go @@ -152,6 +152,16 @@ web3._extend({ call: 'admin_removePeer', params: 1 }), + new web3._extend.Method({ + name: 'addTrustedPeer', + call: 'admin_addTrustedPeer', + params: 1 + }), + new web3._extend.Method({ + name: 'removeTrustedPeer', + call: 'admin_removeTrustedPeer', + params: 1 + }), new web3._extend.Method({ name: 'exportChain', call: 'admin_exportChain', diff --git a/node/api.go b/node/api.go index f44c991539..2656c21203 100644 --- a/node/api.go +++ b/node/api.go @@ -59,7 +59,7 @@ func (api *PrivateAdminAPI) AddPeer(url string) (bool, error) { return true, nil } -// RemovePeer disconnects from a a remote node if the connection exists +// RemovePeer disconnects from a remote node if the connection exists func (api *PrivateAdminAPI) RemovePeer(url string) (bool, error) { // Make sure the server is running, fail otherwise server := api.node.Server() @@ -75,6 +75,37 @@ func (api *PrivateAdminAPI) RemovePeer(url string) (bool, error) { return true, nil } +// AddTrustedPeer allows a remote node to always connect, even if slots are full +func (api *PrivateAdminAPI) AddTrustedPeer(url string) (bool, error) { + // Make sure the server is running, fail otherwise + server := api.node.Server() + if server == nil { + return false, ErrNodeStopped + } + node, err := discover.ParseNode(url) + if err != nil { + return false, fmt.Errorf("invalid enode: %v", err) + } + server.AddTrustedPeer(node) + return true, nil +} + +// RemoveTrustedPeer removes a remote node from the trusted peer set, but it +// does not disconnect it automatically. +func (api *PrivateAdminAPI) RemoveTrustedPeer(url string) (bool, error) { + // Make sure the server is running, fail otherwise + server := api.node.Server() + if server == nil { + return false, ErrNodeStopped + } + node, err := discover.ParseNode(url) + if err != nil { + return false, fmt.Errorf("invalid enode: %v", err) + } + server.RemoveTrustedPeer(node) + return true, nil +} + // PeerEvents creates an RPC subscription which receives peer events from the // node's p2p.Server func (api *PrivateAdminAPI) PeerEvents(ctx context.Context) (*rpc.Subscription, error) { diff --git a/p2p/peer.go b/p2p/peer.go index e8d1f25404..482e3d5064 100644 --- a/p2p/peer.go +++ b/p2p/peer.go @@ -165,7 +165,7 @@ func (p *Peer) String() string { // Inbound returns true if the peer is an inbound connection func (p *Peer) Inbound() bool { - return p.rw.flags&inboundConn != 0 + return p.rw.is(inboundConn) } func newPeer(conn *conn, protocols []Protocol) *Peer { diff --git a/p2p/server.go b/p2p/server.go index 8f860d8f10..669ef740db 100644 --- a/p2p/server.go +++ b/p2p/server.go @@ -23,6 +23,7 @@ import ( "fmt" "net" "sync" + "sync/atomic" "time" "github.com/ethereum/go-ethereum/common" @@ -169,6 +170,8 @@ type Server struct { quit chan struct{} addstatic chan *discover.Node removestatic chan *discover.Node + addtrusted chan *discover.Node + removetrusted chan *discover.Node posthandshake chan *conn addpeer chan *conn delpeer chan peerDrop @@ -185,7 +188,7 @@ type peerDrop struct { requested bool // true if signaled by the peer } -type connFlag int +type connFlag int32 const ( dynDialedConn connFlag = 1 << iota @@ -250,7 +253,18 @@ func (f connFlag) String() string { } func (c *conn) is(f connFlag) bool { - return c.flags&f != 0 + flags := connFlag(atomic.LoadInt32((*int32)(&c.flags))) + return flags&f != 0 +} + +func (c *conn) set(f connFlag, val bool) { + flags := connFlag(atomic.LoadInt32((*int32)(&c.flags))) + if val { + flags |= f + } else { + flags &= ^f + } + atomic.StoreInt32((*int32)(&c.flags), int32(flags)) } // Peers returns all connected peers. @@ -300,6 +314,23 @@ func (srv *Server) RemovePeer(node *discover.Node) { } } +// AddTrustedPeer adds the given node to a reserved whitelist which allows the +// node to always connect, even if the slot are full. +func (srv *Server) AddTrustedPeer(node *discover.Node) { + select { + case srv.addtrusted <- node: + case <-srv.quit: + } +} + +// RemoveTrustedPeer removes the given node from the trusted peer set. +func (srv *Server) RemoveTrustedPeer(node *discover.Node) { + select { + case srv.removetrusted <- node: + case <-srv.quit: + } +} + // SubscribePeers subscribes the given channel to peer events func (srv *Server) SubscribeEvents(ch chan *PeerEvent) event.Subscription { return srv.peerFeed.Subscribe(ch) @@ -411,6 +442,8 @@ func (srv *Server) Start() (err error) { srv.posthandshake = make(chan *conn) srv.addstatic = make(chan *discover.Node) srv.removestatic = make(chan *discover.Node) + srv.addtrusted = make(chan *discover.Node) + srv.removetrusted = make(chan *discover.Node) srv.peerOp = make(chan peerOpFunc) srv.peerOpDone = make(chan struct{}) @@ -547,8 +580,7 @@ func (srv *Server) run(dialstate dialer) { queuedTasks []task // tasks that can't run yet ) // Put trusted nodes into a map to speed up checks. - // Trusted peers are loaded on startup and cannot be - // modified while the server is running. + // Trusted peers are loaded on startup or added via AddTrustedPeer RPC. for _, n := range srv.TrustedNodes { trusted[n.ID] = true } @@ -600,12 +632,32 @@ running: case n := <-srv.removestatic: // This channel is used by RemovePeer to send a // disconnect request to a peer and begin the - // stop keeping the node connected + // stop keeping the node connected. srv.log.Trace("Removing static node", "node", n) dialstate.removeStatic(n) if p, ok := peers[n.ID]; ok { p.Disconnect(DiscRequested) } + case n := <-srv.addtrusted: + // This channel is used by AddTrustedPeer to add an enode + // to the trusted node set. + srv.log.Trace("Adding trusted node", "node", n) + trusted[n.ID] = true + // Mark any already-connected peer as trusted + if p, ok := peers[n.ID]; ok { + p.rw.set(trustedConn, true) + } + case n := <-srv.removetrusted: + // This channel is used by RemoveTrustedPeer to remove an enode + // from the trusted node set. + srv.log.Trace("Removing trusted node", "node", n) + if _, ok := trusted[n.ID]; ok { + delete(trusted, n.ID) + } + // Unmark any already-connected peer as trusted + if p, ok := peers[n.ID]; ok { + p.rw.set(trustedConn, false) + } case op := <-srv.peerOp: // This channel is used by Peers and PeerCount. op(peers) diff --git a/p2p/server_test.go b/p2p/server_test.go index 10c36528eb..3f24a79bae 100644 --- a/p2p/server_test.go +++ b/p2p/server_test.go @@ -148,7 +148,8 @@ func TestServerDial(t *testing.T) { // tell the server to connect tcpAddr := listener.Addr().(*net.TCPAddr) - srv.AddPeer(&discover.Node{ID: remid, IP: tcpAddr.IP, TCP: uint16(tcpAddr.Port)}) + node := &discover.Node{ID: remid, IP: tcpAddr.IP, TCP: uint16(tcpAddr.Port)} + srv.AddPeer(node) select { case conn := <-accepted: @@ -170,6 +171,29 @@ func TestServerDial(t *testing.T) { if !reflect.DeepEqual(peers, []*Peer{peer}) { t.Errorf("Peers mismatch: got %v, want %v", peers, []*Peer{peer}) } + + // Test AddTrustedPeer/RemoveTrustedPeer and changing Trusted flags + // Particularly for race conditions on changing the flag state. + if peer := srv.Peers()[0]; peer.Info().Network.Trusted { + t.Errorf("peer is trusted prematurely: %v", peer) + } + done := make(chan bool) + go func() { + srv.AddTrustedPeer(node) + if peer := srv.Peers()[0]; !peer.Info().Network.Trusted { + t.Errorf("peer is not trusted after AddTrustedPeer: %v", peer) + } + srv.RemoveTrustedPeer(node) + if peer := srv.Peers()[0]; peer.Info().Network.Trusted { + t.Errorf("peer is trusted after RemoveTrustedPeer: %v", peer) + } + done <- true + }() + // Trigger potential race conditions + peer = srv.Peers()[0] + _ = peer.Inbound() + _ = peer.Info() + <-done case <-time.After(1 * time.Second): t.Error("server did not launch peer within one second") } @@ -351,7 +375,8 @@ func TestServerAtCap(t *testing.T) { } } // Try inserting a non-trusted connection. - c := newconn(randomID()) + anotherID := randomID() + c := newconn(anotherID) if err := srv.checkpoint(c, srv.posthandshake); err != DiscTooManyPeers { t.Error("wrong error for insert:", err) } @@ -364,6 +389,87 @@ func TestServerAtCap(t *testing.T) { t.Error("Server did not set trusted flag") } + // Remove from trusted set and try again + srv.RemoveTrustedPeer(&discover.Node{ID: trustedID}) + c = newconn(trustedID) + if err := srv.checkpoint(c, srv.posthandshake); err != DiscTooManyPeers { + t.Error("wrong error for insert:", err) + } + + // Add anotherID to trusted set and try again + srv.AddTrustedPeer(&discover.Node{ID: anotherID}) + c = newconn(anotherID) + if err := srv.checkpoint(c, srv.posthandshake); err != nil { + t.Error("unexpected error for trusted conn @posthandshake:", err) + } + if !c.is(trustedConn) { + t.Error("Server did not set trusted flag") + } +} + +func TestServerPeerLimits(t *testing.T) { + srvkey := newkey() + + clientid := randomID() + clientnode := &discover.Node{ID: clientid} + + var tp *setupTransport = &setupTransport{ + id: clientid, + phs: &protoHandshake{ + ID: clientid, + // Force "DiscUselessPeer" due to unmatching caps + // Caps: []Cap{discard.cap()}, + }, + } + var flags connFlag = dynDialedConn + var dialDest *discover.Node = &discover.Node{ID: clientid} + + srv := &Server{ + Config: Config{ + PrivateKey: srvkey, + MaxPeers: 0, + NoDial: true, + Protocols: []Protocol{discard}, + }, + newTransport: func(fd net.Conn) transport { return tp }, + log: log.New(), + } + if err := srv.Start(); err != nil { + t.Fatalf("couldn't start server: %v", err) + } + defer srv.Stop() + + // Check that server is full (MaxPeers=0) + conn, _ := net.Pipe() + srv.SetupConn(conn, flags, dialDest) + if tp.closeErr != DiscTooManyPeers { + t.Errorf("unexpected close error: %q", tp.closeErr) + } + conn.Close() + + srv.AddTrustedPeer(clientnode) + + // Check that server allows a trusted peer despite being full. + conn, _ = net.Pipe() + srv.SetupConn(conn, flags, dialDest) + if tp.closeErr == DiscTooManyPeers { + t.Errorf("failed to bypass MaxPeers with trusted node: %q", tp.closeErr) + } + + if tp.closeErr != DiscUselessPeer { + t.Errorf("unexpected close error: %q", tp.closeErr) + } + conn.Close() + + srv.RemoveTrustedPeer(clientnode) + + // Check that server is full again. + conn, _ = net.Pipe() + srv.SetupConn(conn, flags, dialDest) + if tp.closeErr != DiscTooManyPeers { + t.Errorf("unexpected close error: %q", tp.closeErr) + } + conn.Close() } func TestServerSetupConn(t *testing.T) {