rpc: Add admin_addTrustedPeer and admin_removeTrustedPeer.

These RPC calls are analogous to Parity's parity_addReservedPeer and
parity_removeReservedPeer.

They are useful for adjusting the trusted peer set during runtime,
without requiring restarting the server.

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) {