// Copyright (C) 2016 The Syncthing Authors. // // This Source Code Form is subject to the terms of the Mozilla Public // License, v. 2.0. If a copy of the MPL was not distributed with this file, // You can obtain one at https://mozilla.org/MPL/2.0/. package connections import ( "crypto/tls" "fmt" "io" "net" "net/url" "time" "github.com/syncthing/syncthing/lib/config" "github.com/syncthing/syncthing/lib/nat" "github.com/syncthing/syncthing/lib/protocol" ) // Connection is what we expose to the outside. It is a protocol.Connection // that can be closed and has some metadata. type Connection interface { protocol.Connection io.Closer Type() string RemoteAddr() net.Addr } // completeConn is the aggregation of an internalConn and the // protocol.Connection running on top of it. It implements the Connection // interface. type completeConn struct { internalConn protocol.Connection } // internalConn is the raw TLS connection plus some metadata on where it // came from (type, priority). type internalConn struct { *tls.Conn connType connType priority int } type connType int const ( connTypeRelayClient connType = iota connTypeRelayServer connTypeTCPClient connTypeTCPServer connTypeKCPClient connTypeKCPServer ) func (t connType) String() string { switch t { case connTypeRelayClient: return "relay-client" case connTypeRelayServer: return "relay-server" case connTypeTCPClient: return "tcp-client" case connTypeTCPServer: return "tcp-server" case connTypeKCPClient: return "kcp-client" case connTypeKCPServer: return "kcp-server" default: return "unknown-type" } } func (c internalConn) Type() string { return c.connType.String() } func (c internalConn) String() string { return fmt.Sprintf("%s-%s/%s", c.LocalAddr(), c.RemoteAddr(), c.connType.String()) } type dialerFactory interface { New(*config.Wrapper, *tls.Config) genericDialer Priority() int Enabled(config.Configuration) bool String() string } type genericDialer interface { Dial(protocol.DeviceID, *url.URL) (internalConn, error) RedialFrequency() time.Duration } type listenerFactory interface { New(*url.URL, *config.Wrapper, *tls.Config, chan internalConn, *nat.Service) genericListener Enabled(config.Configuration) bool } type genericListener interface { Serve() Stop() URI() *url.URL // A given address can potentially be mutated by the listener. // For example we bind to tcp://0.0.0.0, but that for example might return // tcp://gateway1.ip and tcp://gateway2.ip as WAN addresses due to there // being multiple gateways, and us managing to get a UPnP mapping on both // and tcp://192.168.0.1 and tcp://10.0.0.1 due to there being multiple // network interfaces. (The later case for LAN addresses is made up just // to provide an example) WANAddresses() []*url.URL LANAddresses() []*url.URL Error() error OnAddressesChanged(func(genericListener)) String() string Factory() listenerFactory } type Model interface { protocol.Model AddConnection(conn Connection, hello protocol.HelloResult) ConnectedTo(remoteID protocol.DeviceID) bool OnHello(protocol.DeviceID, net.Addr, protocol.HelloResult) error GetHello(protocol.DeviceID) protocol.HelloIntf } // serviceFunc wraps a function to create a suture.Service without stop // functionality. type serviceFunc func() func (f serviceFunc) Serve() { f() } func (f serviceFunc) Stop() {} type onAddressesChangedNotifier struct { callbacks []func(genericListener) } func (o *onAddressesChangedNotifier) OnAddressesChanged(callback func(genericListener)) { o.callbacks = append(o.callbacks, callback) } func (o *onAddressesChangedNotifier) notifyAddressesChanged(l genericListener) { for _, callback := range o.callbacks { callback(l) } }