Merge pull request #16333 from shazow/addremovetrustedpeer

rpc: Add admin_addTrustedPeer and admin_removeTrustedPeer.

1 files changed, 57 insertions, 5 deletions

diff --git a/p2p/server.go b/p2p/server.go
index 8f860d8f1..669ef740d 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)