21 "github.com/anacrolix/chansync"
22 "github.com/anacrolix/chansync/events"
23 "github.com/anacrolix/dht/v2"
24 "github.com/anacrolix/dht/v2/krpc"
25 . "github.com/anacrolix/generics"
26 g "github.com/anacrolix/generics"
27 "github.com/anacrolix/log"
28 "github.com/anacrolix/missinggo/perf"
29 "github.com/anacrolix/missinggo/v2"
30 "github.com/anacrolix/missinggo/v2/bitmap"
31 "github.com/anacrolix/missinggo/v2/pproffd"
32 "github.com/anacrolix/sync"
33 "github.com/cespare/xxhash"
34 "github.com/davecgh/go-spew/spew"
35 "github.com/dustin/go-humanize"
36 gbtree "github.com/google/btree"
37 "github.com/pion/datachannel"
38 "github.com/pion/webrtc/v3"
40 "github.com/anacrolix/torrent/bencode"
41 "github.com/anacrolix/torrent/internal/check"
42 "github.com/anacrolix/torrent/internal/limiter"
43 "github.com/anacrolix/torrent/iplist"
44 "github.com/anacrolix/torrent/metainfo"
45 "github.com/anacrolix/torrent/mse"
46 pp "github.com/anacrolix/torrent/peer_protocol"
47 request_strategy "github.com/anacrolix/torrent/request-strategy"
48 "github.com/anacrolix/torrent/storage"
49 "github.com/anacrolix/torrent/tracker"
50 "github.com/anacrolix/torrent/types/infohash"
51 infohash_v2 "github.com/anacrolix/torrent/types/infohash-v2"
52 "github.com/anacrolix/torrent/webtorrent"
55 // Clients contain zero or more Torrents. A Client manages a blocklist, the
56 // TCP/UDP protocol ports, and DHT as desired.
58 // An aggregate of stats over all connections. First in struct to ensure 64-bit alignment of
64 closed chansync.SetOnce
70 defaultStorage *storage.Client
74 dhtServers []DhtServer
75 ipBlockList iplist.Ranger
77 // Set of addresses that have our client ID. This intentionally will
78 // include ourselves if we end up trying to connect to our own address
79 // through legitimate channels.
80 dopplegangerAddrs map[string]struct{}
81 badPeerIPs map[netip.Addr]struct{}
83 torrents map[*Torrent]struct{}
84 // All Torrents by their short infohashes (v1 if valid, and truncated v2 if valid). Unless the
85 // info has been obtained, there's no knowing if an infohash belongs to v1 or v2.
86 torrentsByShortHash map[InfoHash]*Torrent
88 pieceRequestOrder map[interface{}]*request_strategy.PieceRequestOrder
90 acceptLimiter map[ipStr]int
93 websocketTrackers websocketTrackers
95 activeAnnounceLimiter limiter.Instance
96 httpClient *http.Client
98 clientHolepunchAddrSets
100 defaultLocalLtepProtocolMap LocalLtepProtocolMap
105 func (cl *Client) BadPeerIPs() (ips []string) {
107 ips = cl.badPeerIPsLocked()
112 func (cl *Client) badPeerIPsLocked() (ips []string) {
113 ips = make([]string, len(cl.badPeerIPs))
115 for k := range cl.badPeerIPs {
122 func (cl *Client) PeerID() PeerID {
126 // Returns the port number for the first listener that has one. No longer assumes that all port
127 // numbers are the same, due to support for custom listeners. Returns zero if no port number is
129 func (cl *Client) LocalPort() (port int) {
130 for i := 0; i < len(cl.listeners); i += 1 {
131 if port = addrPortOrZero(cl.listeners[i].Addr()); port != 0 {
138 func writeDhtServerStatus(w io.Writer, s DhtServer) {
139 dhtStats := s.Stats()
140 fmt.Fprintf(w, " ID: %x\n", s.ID())
141 spew.Fdump(w, dhtStats)
144 // Writes out a human readable status of the client, such as for writing to a
146 func (cl *Client) WriteStatus(_w io.Writer) {
149 w := bufio.NewWriter(_w)
151 fmt.Fprintf(w, "Listen port: %d\n", cl.LocalPort())
152 fmt.Fprintf(w, "Peer ID: %+q\n", cl.PeerID())
153 fmt.Fprintf(w, "Extension bits: %v\n", cl.config.Extensions)
154 fmt.Fprintf(w, "Announce key: %x\n", cl.announceKey())
155 fmt.Fprintf(w, "Banned IPs: %d\n", len(cl.badPeerIPsLocked()))
156 cl.eachDhtServer(func(s DhtServer) {
157 fmt.Fprintf(w, "%s DHT server at %s:\n", s.Addr().Network(), s.Addr().String())
158 writeDhtServerStatus(w, s)
160 dumpStats(w, cl.statsLocked())
161 torrentsSlice := cl.torrentsAsSlice()
162 fmt.Fprintf(w, "# Torrents: %d\n", len(torrentsSlice))
164 sort.Slice(torrentsSlice, func(l, r int) bool {
165 return torrentsSlice[l].canonicalShortInfohash().AsString() < torrentsSlice[r].canonicalShortInfohash().AsString()
167 for _, t := range torrentsSlice {
169 fmt.Fprint(w, "<unknown name>")
171 fmt.Fprint(w, t.name())
177 "%f%% of %d bytes (%s)",
178 100*(1-float64(t.bytesMissingLocked())/float64(t.info.TotalLength())),
180 humanize.Bytes(uint64(t.length())))
182 w.WriteString("<missing metainfo>")
190 func (cl *Client) initLogger() {
191 logger := cl.config.Logger
196 logger = logger.WithFilterLevel(log.Debug)
198 cl.logger = logger.WithValues(cl)
201 func (cl *Client) announceKey() int32 {
202 return int32(binary.BigEndian.Uint32(cl.peerID[16:20]))
205 // Initializes a bare minimum Client. *Client and *ClientConfig must not be nil.
206 func (cl *Client) init(cfg *ClientConfig) {
208 g.MakeMap(&cl.dopplegangerAddrs)
209 g.MakeMap(&cl.torrentsByShortHash)
210 g.MakeMap(&cl.torrents)
211 cl.torrentsByShortHash = make(map[metainfo.Hash]*Torrent)
212 cl.activeAnnounceLimiter.SlotsPerKey = 2
213 cl.event.L = cl.locker()
214 cl.ipBlockList = cfg.IPBlocklist
215 cl.httpClient = &http.Client{
216 Transport: cfg.WebTransport,
218 if cl.httpClient.Transport == nil {
219 cl.httpClient.Transport = &http.Transport{
220 Proxy: cfg.HTTPProxy,
221 DialContext: cfg.HTTPDialContext,
222 // I think this value was observed from some webseeds. It seems reasonable to extend it
223 // to other uses of HTTP from the client.
227 cl.defaultLocalLtepProtocolMap = makeBuiltinLtepProtocols(!cfg.DisablePEX)
230 func NewClient(cfg *ClientConfig) (cl *Client, err error) {
232 cfg = NewDefaultClientConfig()
237 go cl.acceptLimitClearer()
246 storageImpl := cfg.DefaultStorage
247 if storageImpl == nil {
248 // We'd use mmap by default but HFS+ doesn't support sparse files.
249 storageImplCloser := storage.NewFile(cfg.DataDir)
250 cl.onClose = append(cl.onClose, func() {
251 if err := storageImplCloser.Close(); err != nil {
252 cl.logger.Printf("error closing default storage: %s", err)
255 storageImpl = storageImplCloser
257 cl.defaultStorage = storage.NewClient(storageImpl)
259 if cfg.PeerID != "" {
260 missinggo.CopyExact(&cl.peerID, cfg.PeerID)
262 o := copy(cl.peerID[:], cfg.Bep20)
263 _, err = rand.Read(cl.peerID[o:])
265 panic("error generating peer id")
269 builtinListenNetworks := cl.listenNetworks()
270 sockets, err := listenAll(
271 builtinListenNetworks,
272 cl.config.ListenHost,
273 cl.config.ListenPort,
280 if len(sockets) == 0 && len(builtinListenNetworks) != 0 {
281 err = fmt.Errorf("no sockets created for networks %v", builtinListenNetworks)
288 for _, _s := range sockets {
289 s := _s // Go is fucking retarded.
290 cl.onClose = append(cl.onClose, func() { go s.Close() })
291 if peerNetworkEnabled(parseNetworkString(s.Addr().Network()), cl.config) {
292 cl.dialers = append(cl.dialers, s)
293 cl.listeners = append(cl.listeners, s)
294 if cl.config.AcceptPeerConnections {
295 go cl.acceptConnections(s)
302 for _, s := range sockets {
303 if pc, ok := s.(net.PacketConn); ok {
304 ds, err := cl.NewAnacrolixDhtServer(pc)
308 cl.dhtServers = append(cl.dhtServers, AnacrolixDhtServerWrapper{ds})
309 cl.onClose = append(cl.onClose, func() { ds.Close() })
314 var ICEServers []webrtc.ICEServer
315 if cl.config.ICEServerList != nil {
316 ICEServers = cl.config.ICEServerList
317 } else if cl.config.ICEServers != nil {
318 ICEServers = []webrtc.ICEServer{{URLs: cl.config.ICEServers}}
321 cl.websocketTrackers = websocketTrackers{
324 GetAnnounceRequest: func(
325 event tracker.AnnounceEvent, infoHash [20]byte,
327 tracker.AnnounceRequest, error,
331 t, ok := cl.torrentsByShortHash[infoHash]
333 return tracker.AnnounceRequest{}, errors.New("torrent not tracked by client")
335 return t.announceRequest(event, infoHash), nil
337 Proxy: cl.config.HTTPProxy,
338 WebsocketTrackerHttpHeader: cl.config.WebsocketTrackerHttpHeader,
339 ICEServers: ICEServers,
340 DialContext: cl.config.TrackerDialContext,
341 OnConn: func(dc datachannel.ReadWriteCloser, dcc webtorrent.DataChannelContext) {
344 t, ok := cl.torrentsByShortHash[dcc.InfoHash]
346 cl.logger.WithDefaultLevel(log.Warning).Printf(
347 "got webrtc conn for unloaded torrent with infohash %x",
353 go t.onWebRtcConn(dc, dcc)
360 func (cl *Client) AddDhtServer(d DhtServer) {
361 cl.dhtServers = append(cl.dhtServers, d)
364 // Adds a Dialer for outgoing connections. All Dialers are used when attempting to connect to a
365 // given address for any Torrent.
366 func (cl *Client) AddDialer(d Dialer) {
369 cl.dialers = append(cl.dialers, d)
370 for t := range cl.torrents {
375 func (cl *Client) Listeners() []Listener {
379 // Registers a Listener, and starts Accepting on it. You must Close Listeners provided this way
381 func (cl *Client) AddListener(l Listener) {
382 cl.listeners = append(cl.listeners, l)
383 if cl.config.AcceptPeerConnections {
384 go cl.acceptConnections(l)
388 func (cl *Client) firewallCallback(net.Addr) bool {
390 block := !cl.wantConns() || !cl.config.AcceptPeerConnections
393 torrent.Add("connections firewalled", 1)
395 torrent.Add("connections not firewalled", 1)
400 func (cl *Client) listenOnNetwork(n network) bool {
401 if n.Ipv4 && cl.config.DisableIPv4 {
404 if n.Ipv6 && cl.config.DisableIPv6 {
407 if n.Tcp && cl.config.DisableTCP {
410 if n.Udp && cl.config.DisableUTP && cl.config.NoDHT {
416 func (cl *Client) listenNetworks() (ns []network) {
417 for _, n := range allPeerNetworks {
418 if cl.listenOnNetwork(n) {
425 // Creates an anacrolix/dht Server, as would be done internally in NewClient, for the given conn.
426 func (cl *Client) NewAnacrolixDhtServer(conn net.PacketConn) (s *dht.Server, err error) {
427 logger := cl.logger.WithNames("dht", conn.LocalAddr().String())
428 cfg := dht.ServerConfig{
429 IPBlocklist: cl.ipBlockList,
431 OnAnnouncePeer: cl.onDHTAnnouncePeer,
432 PublicIP: func() net.IP {
433 if connIsIpv6(conn) && cl.config.PublicIp6 != nil {
434 return cl.config.PublicIp6
436 return cl.config.PublicIp4
438 StartingNodes: cl.config.DhtStartingNodes(conn.LocalAddr().Network()),
439 OnQuery: cl.config.DHTOnQuery,
442 if f := cl.config.ConfigureAnacrolixDhtServer; f != nil {
445 s, err = dht.NewServer(&cfg)
447 go s.TableMaintainer()
452 func (cl *Client) Closed() events.Done {
453 return cl.closed.Done()
456 func (cl *Client) eachDhtServer(f func(DhtServer)) {
457 for _, ds := range cl.dhtServers {
462 // Stops the client. All connections to peers are closed and all activity will come to a halt.
463 func (cl *Client) Close() (errs []error) {
464 var closeGroup sync.WaitGroup // For concurrent cleanup to complete before returning
466 for t := range cl.torrents {
467 err := t.close(&closeGroup)
469 errs = append(errs, err)
472 for i := range cl.onClose {
473 cl.onClose[len(cl.onClose)-1-i]()
478 closeGroup.Wait() // defer is LIFO. We want to Wait() after cl.unlock()
482 func (cl *Client) ipBlockRange(ip net.IP) (r iplist.Range, blocked bool) {
483 if cl.ipBlockList == nil {
486 return cl.ipBlockList.Lookup(ip)
489 func (cl *Client) ipIsBlocked(ip net.IP) bool {
490 _, blocked := cl.ipBlockRange(ip)
494 func (cl *Client) wantConns() bool {
495 if cl.config.AlwaysWantConns {
498 for t := range cl.torrents {
499 if t.wantIncomingConns() {
506 // TODO: Apply filters for non-standard networks, particularly rate-limiting.
507 func (cl *Client) rejectAccepted(conn net.Conn) error {
509 return errors.New("don't want conns right now")
511 ra := conn.RemoteAddr()
512 if rip := addrIpOrNil(ra); rip != nil {
513 if cl.config.DisableIPv4Peers && rip.To4() != nil {
514 return errors.New("ipv4 peers disabled")
516 if cl.config.DisableIPv4 && len(rip) == net.IPv4len {
517 return errors.New("ipv4 disabled")
519 if cl.config.DisableIPv6 && len(rip) == net.IPv6len && rip.To4() == nil {
520 return errors.New("ipv6 disabled")
522 if cl.rateLimitAccept(rip) {
523 return errors.New("source IP accepted rate limited")
525 if cl.badPeerIPPort(rip, missinggo.AddrPort(ra)) {
526 return errors.New("bad source addr")
532 func (cl *Client) acceptConnections(l Listener) {
534 conn, err := l.Accept()
535 torrent.Add("client listener accepts", 1)
537 holepunchAddr, holepunchErr := addrPortFromPeerRemoteAddr(conn.RemoteAddr())
538 if holepunchErr == nil {
540 if g.MapContains(cl.undialableWithoutHolepunch, holepunchAddr) {
541 setAdd(&cl.accepted, holepunchAddr)
544 cl.undialableWithoutHolepunchDialedAfterHolepunchConnect,
547 setAdd(&cl.probablyOnlyConnectedDueToHolepunch, holepunchAddr)
552 conn = pproffd.WrapNetConn(conn)
554 closed := cl.closed.IsSet()
556 if !closed && conn != nil {
557 reject = cl.rejectAccepted(conn)
567 log.Fmsg("error accepting connection: %s", err).LogLevel(log.Debug, cl.logger)
572 torrent.Add("rejected accepted connections", 1)
573 cl.logger.LazyLog(log.Debug, func() log.Msg {
574 return log.Fmsg("rejecting accepted conn: %v", reject)
578 go cl.incomingConnection(conn)
580 cl.logger.LazyLog(log.Debug, func() log.Msg {
581 return log.Fmsg("accepted %q connection at %q from %q",
587 torrent.Add(fmt.Sprintf("accepted conn remote IP len=%d", len(addrIpOrNil(conn.RemoteAddr()))), 1)
588 torrent.Add(fmt.Sprintf("accepted conn network=%s", conn.RemoteAddr().Network()), 1)
589 torrent.Add(fmt.Sprintf("accepted on %s listener", l.Addr().Network()), 1)
594 // Creates the PeerConn.connString for a regular net.Conn PeerConn.
595 func regularNetConnPeerConnConnString(nc net.Conn) string {
596 return fmt.Sprintf("%s-%s", nc.LocalAddr(), nc.RemoteAddr())
599 func (cl *Client) incomingConnection(nc net.Conn) {
601 if tc, ok := nc.(*net.TCPConn); ok {
604 remoteAddr, _ := tryIpPortFromNetAddr(nc.RemoteAddr())
605 c := cl.newConnection(
609 remoteAddr: nc.RemoteAddr(),
610 localPublicAddr: cl.publicAddr(remoteAddr.IP),
611 network: nc.RemoteAddr().Network(),
612 connString: regularNetConnPeerConnConnString(nc),
614 c.Discovery = PeerSourceIncoming
615 cl.runReceivedConn(c)
622 // Returns a handle to the given torrent, if it's present in the client.
623 func (cl *Client) Torrent(ih metainfo.Hash) (t *Torrent, ok bool) {
626 t, ok = cl.torrentsByShortHash[ih]
630 type DialResult struct {
635 func countDialResult(err error) {
637 torrent.Add("successful dials", 1)
639 torrent.Add("unsuccessful dials", 1)
643 func reducedDialTimeout(minDialTimeout, max time.Duration, halfOpenLimit, pendingPeers int) (ret time.Duration) {
644 ret = max / time.Duration((pendingPeers+halfOpenLimit)/halfOpenLimit)
645 if ret < minDialTimeout {
651 // Returns whether an address is known to connect to a client with our own ID.
652 func (cl *Client) dopplegangerAddr(addr string) bool {
653 _, ok := cl.dopplegangerAddrs[addr]
657 // Returns a connection over UTP or TCP, whichever is first to connect.
658 func (cl *Client) dialFirst(ctx context.Context, addr string) (res DialResult) {
659 return DialFirst(ctx, addr, cl.dialers)
662 // Returns a connection over UTP or TCP, whichever is first to connect.
663 func DialFirst(ctx context.Context, addr string, dialers []Dialer) (res DialResult) {
667 defer pool.startDrainer()
668 for _, _s := range dialers {
671 return pool.getFirst()
674 func dialFromSocket(ctx context.Context, s Dialer, addr string) net.Conn {
675 c, err := s.Dial(ctx, addr)
677 log.ContextLogger(ctx).Levelf(log.Debug, "error dialing %q: %v", addr, err)
679 // This is a bit optimistic, but it looks non-trivial to thread this through the proxy code. Set
680 // it now in case we close the connection forthwith. Note this is also done in the TCP dialer
681 // code to increase the chance it's done.
682 if tc, ok := c.(*net.TCPConn); ok {
689 func (cl *Client) noLongerHalfOpen(t *Torrent, addr string, attemptKey outgoingConnAttemptKey) {
690 path := t.getHalfOpenPath(addr, attemptKey)
692 panic("should exist")
696 if cl.numHalfOpen < 0 {
697 panic("should not be possible")
699 for t := range cl.torrents {
704 func (cl *Client) countHalfOpenFromTorrents() (count int) {
705 for t := range cl.torrents {
706 count += t.numHalfOpenAttempts()
711 // Performs initiator handshakes and returns a connection. Returns nil *PeerConn if no connection
712 // for valid reasons.
713 func (cl *Client) initiateProtocolHandshakes(
718 newConnOpts newConnectionOpts,
720 c *PeerConn, err error,
722 c = cl.newConnection(nc, newConnOpts)
723 c.headerEncrypted = encryptHeader
724 ctx, cancel := context.WithTimeout(ctx, cl.config.HandshakesTimeout)
726 dl, ok := ctx.Deadline()
730 err = nc.SetDeadline(dl)
734 err = cl.initiateHandshakes(c, t)
738 func doProtocolHandshakeOnDialResult(
740 obfuscatedHeader bool,
744 c *PeerConn, err error,
748 addrIpPort, _ := tryIpPortFromNetAddr(addr)
749 c, err = cl.initiateProtocolHandshakes(
750 context.Background(), nc, t, obfuscatedHeader,
754 // It would be possible to retrieve a public IP from the dialer used here?
755 localPublicAddr: cl.publicAddr(addrIpPort.IP),
756 network: dr.Dialer.DialerNetwork(),
757 connString: regularNetConnPeerConnConnString(nc),
765 // Returns nil connection and nil error if no connection could be established for valid reasons.
766 func (cl *Client) dialAndCompleteHandshake(opts outgoingConnOpts) (c *PeerConn, err error) {
767 // It would be better if dial rate limiting could be tested when considering to open connections
768 // instead. Doing it here means if the limit is low, and the half-open limit is high, we could
769 // end up with lots of outgoing connection attempts pending that were initiated on stale data.
771 dialReservation := cl.config.DialRateLimiter.Reserve()
772 if !opts.receivedHolepunchConnect {
773 if !dialReservation.OK() {
774 err = errors.New("can't make dial limit reservation")
777 time.Sleep(dialReservation.Delay())
780 torrent.Add("establish outgoing connection", 1)
781 addr := opts.peerInfo.Addr
782 dialPool := dialPool{
783 resCh: make(chan DialResult),
786 defer dialPool.startDrainer()
787 dialTimeout := opts.t.getDialTimeoutUnlocked()
789 ctx, cancel := context.WithTimeout(context.Background(), dialTimeout)
791 for _, d := range cl.dialers {
795 holepunchAddr, holepunchAddrErr := addrPortFromPeerRemoteAddr(addr)
796 headerObfuscationPolicy := opts.HeaderObfuscationPolicy
797 obfuscatedHeaderFirst := headerObfuscationPolicy.Preferred
798 firstDialResult := dialPool.getFirst()
799 if firstDialResult.Conn == nil {
800 // No dialers worked. Try to initiate a holepunching rendezvous.
801 if holepunchAddrErr == nil {
803 if !opts.receivedHolepunchConnect {
804 g.MakeMapIfNilAndSet(&cl.undialableWithoutHolepunch, holepunchAddr, struct{}{})
806 if !opts.skipHolepunchRendezvous {
807 opts.t.trySendHolepunchRendezvous(holepunchAddr)
811 err = fmt.Errorf("all initial dials failed")
814 if opts.receivedHolepunchConnect && holepunchAddrErr == nil {
816 if g.MapContains(cl.undialableWithoutHolepunch, holepunchAddr) {
817 g.MakeMapIfNilAndSet(&cl.dialableOnlyAfterHolepunch, holepunchAddr, struct{}{})
819 g.MakeMapIfNil(&cl.dialedSuccessfullyAfterHolepunchConnect)
820 g.MapInsert(cl.dialedSuccessfullyAfterHolepunchConnect, holepunchAddr, struct{}{})
823 c, err = doProtocolHandshakeOnDialResult(
825 obfuscatedHeaderFirst,
830 torrent.Add("initiated conn with preferred header obfuscation", 1)
835 "error doing protocol handshake with header obfuscation %v",
836 obfuscatedHeaderFirst,
838 firstDialResult.Conn.Close()
839 // We should have just tried with the preferred header obfuscation. If it was required, there's nothing else to try.
840 if headerObfuscationPolicy.RequirePreferred {
843 // Reuse the dialer that returned already but failed to handshake.
845 ctx, cancel := context.WithTimeout(context.Background(), dialTimeout)
847 dialPool.add(ctx, firstDialResult.Dialer)
849 secondDialResult := dialPool.getFirst()
850 if secondDialResult.Conn == nil {
853 c, err = doProtocolHandshakeOnDialResult(
855 !obfuscatedHeaderFirst,
860 torrent.Add("initiated conn with fallback header obfuscation", 1)
865 "error doing protocol handshake with header obfuscation %v",
866 !obfuscatedHeaderFirst,
868 secondDialResult.Conn.Close()
872 type outgoingConnOpts struct {
875 // Don't attempt to connect unless a connect message is received after initiating a rendezvous.
876 requireRendezvous bool
877 // Don't send rendezvous requests to eligible relays.
878 skipHolepunchRendezvous bool
879 // Outgoing connection attempt is in response to holepunch connect message.
880 receivedHolepunchConnect bool
881 HeaderObfuscationPolicy HeaderObfuscationPolicy
884 // Called to dial out and run a connection. The addr we're given is already
885 // considered half-open.
886 func (cl *Client) outgoingConnection(
887 opts outgoingConnOpts,
888 attemptKey outgoingConnAttemptKey,
890 c, err := cl.dialAndCompleteHandshake(opts)
892 c.conn.SetWriteDeadline(time.Time{})
896 // Don't release lock between here and addPeerConn, unless it's for failure.
897 cl.noLongerHalfOpen(opts.t, opts.peerInfo.Addr.String(), attemptKey)
902 "error establishing outgoing connection to %v: %v",
910 c.Discovery = opts.peerInfo.Source
911 c.trusted = opts.peerInfo.Trusted
912 opts.t.runHandshookConnLoggingErr(c)
915 // The port number for incoming peer connections. 0 if the client isn't listening.
916 func (cl *Client) incomingPeerPort() int {
917 return cl.LocalPort()
920 func (cl *Client) initiateHandshakes(c *PeerConn, t *Torrent) (err error) {
921 if c.headerEncrypted {
923 rw, c.cryptoMethod, err = mse.InitiateHandshake(
928 t.canonicalShortInfohash().Bytes(),
930 cl.config.CryptoProvides,
934 return fmt.Errorf("header obfuscation handshake: %w", err)
937 localReservedBits := cl.config.Extensions
938 handshakeIh := *t.canonicalShortInfohash()
939 // If we're sending the v1 infohash, and we know the v2 infohash, set the v2 upgrade bit. This
940 // means the peer can send the v2 infohash in the handshake to upgrade the connection.
941 localReservedBits.SetBit(pp.ExtensionBitV2Upgrade, g.Some(handshakeIh) == t.infoHash && t.infoHashV2.Ok)
942 ih, err := cl.connBtHandshake(c, &handshakeIh, localReservedBits)
944 return fmt.Errorf("bittorrent protocol handshake: %w", err)
946 if g.Some(ih) == t.infoHash {
949 if t.infoHashV2.Ok && *t.infoHashV2.Value.ToShort() == ih {
950 torrent.Add("initiated handshakes upgraded to v2", 1)
954 err = errors.New("bittorrent protocol handshake: peer infohash didn't match")
958 // Calls f with any secret keys. Note that it takes the Client lock, and so must be used from code
959 // that won't also try to take the lock. This saves us copying all the infohashes everytime.
960 func (cl *Client) forSkeys(f func([]byte) bool) {
963 if false { // Emulate the bug from #114
965 for ih := range cl.torrentsByShortHash {
969 for range cl.torrentsByShortHash {
976 for ih := range cl.torrentsByShortHash {
983 func (cl *Client) handshakeReceiverSecretKeys() mse.SecretKeyIter {
984 if ret := cl.config.Callbacks.ReceiveEncryptedHandshakeSkeys; ret != nil {
990 // Do encryption and bittorrent handshakes as receiver.
991 func (cl *Client) receiveHandshakes(c *PeerConn) (t *Torrent, err error) {
992 defer perf.ScopeTimerErr(&err)()
994 rw, c.headerEncrypted, c.cryptoMethod, err = handleEncryption(
996 cl.handshakeReceiverSecretKeys(),
997 cl.config.HeaderObfuscationPolicy,
998 cl.config.CryptoSelector,
1001 if err == nil || err == mse.ErrNoSecretKeyMatch {
1002 if c.headerEncrypted {
1003 torrent.Add("handshakes received encrypted", 1)
1005 torrent.Add("handshakes received unencrypted", 1)
1008 torrent.Add("handshakes received with error while handling encryption", 1)
1011 if err == mse.ErrNoSecretKeyMatch {
1016 if cl.config.HeaderObfuscationPolicy.RequirePreferred && c.headerEncrypted != cl.config.HeaderObfuscationPolicy.Preferred {
1017 err = errors.New("connection does not have required header obfuscation")
1020 ih, err := cl.connBtHandshake(c, nil, cl.config.Extensions)
1022 return nil, fmt.Errorf("during bt handshake: %w", err)
1026 t = cl.torrentsByShortHash[ih]
1027 if t != nil && t.infoHashV2.Ok && *t.infoHashV2.Value.ToShort() == ih {
1028 torrent.Add("v2 handshakes received", 1)
1036 var successfulPeerWireProtocolHandshakePeerReservedBytes expvar.Map
1040 "successful_peer_wire_protocol_handshake_peer_reserved_bytes",
1041 &successfulPeerWireProtocolHandshakePeerReservedBytes)
1044 func (cl *Client) connBtHandshake(c *PeerConn, ih *metainfo.Hash, reservedBits PeerExtensionBits) (ret metainfo.Hash, err error) {
1045 res, err := pp.Handshake(c.rw(), ih, cl.peerID, reservedBits)
1049 successfulPeerWireProtocolHandshakePeerReservedBytes.Add(
1050 hex.EncodeToString(res.PeerExtensionBits[:]), 1)
1052 c.PeerExtensionBytes = res.PeerExtensionBits
1053 c.PeerID = res.PeerID
1054 c.completedHandshake = time.Now()
1055 if cb := cl.config.Callbacks.CompletedHandshake; cb != nil {
1061 func (cl *Client) runReceivedConn(c *PeerConn) {
1062 err := c.conn.SetDeadline(time.Now().Add(cl.config.HandshakesTimeout))
1066 t, err := cl.receiveHandshakes(c)
1068 cl.logger.LazyLog(log.Debug, func() log.Msg {
1070 "error receiving handshakes on %v: %s", c, err,
1072 "network", c.Network,
1075 torrent.Add("error receiving handshake", 1)
1077 cl.onBadAccept(c.RemoteAddr)
1082 torrent.Add("received handshake for unloaded torrent", 1)
1083 cl.logger.LazyLog(log.Debug, func() log.Msg {
1084 return log.Fmsg("received handshake for unloaded torrent")
1087 cl.onBadAccept(c.RemoteAddr)
1091 torrent.Add("received handshake for loaded torrent", 1)
1092 c.conn.SetWriteDeadline(time.Time{})
1095 t.runHandshookConnLoggingErr(c)
1098 // Client lock must be held before entering this.
1099 func (t *Torrent) runHandshookConn(pc *PeerConn) error {
1102 for i, b := range cl.config.MinPeerExtensions {
1103 if pc.PeerExtensionBytes[i]&b != b {
1104 return fmt.Errorf("peer did not meet minimum peer extensions: %x", pc.PeerExtensionBytes[:])
1107 if pc.PeerID == cl.peerID {
1110 addr := pc.RemoteAddr.String()
1111 cl.dopplegangerAddrs[addr] = struct{}{}
1113 // Because the remote address is not necessarily the same as its client's torrent listen
1114 // address, we won't record the remote address as a doppleganger. Instead, the initiator
1115 // can record *us* as the doppleganger.
1117 t.logger.Levelf(log.Debug, "local and remote peer ids are the same")
1120 pc.r = deadlineReader{pc.conn, pc.r}
1121 completedHandshakeConnectionFlags.Add(pc.connectionFlags(), 1)
1122 if connIsIpv6(pc.conn) {
1123 torrent.Add("completed handshake over ipv6", 1)
1125 if err := t.addPeerConn(pc); err != nil {
1126 return fmt.Errorf("adding connection: %w", err)
1128 defer t.dropConnection(pc)
1129 pc.addBuiltinLtepProtocols(!cl.config.DisablePEX)
1130 for _, cb := range pc.callbacks.PeerConnAdded {
1133 pc.startMessageWriter()
1134 pc.sendInitialMessages()
1135 pc.initUpdateRequestsTimer()
1136 err := pc.mainReadLoop()
1138 return fmt.Errorf("main read loop: %w", err)
1143 func (p *Peer) initUpdateRequestsTimer() {
1145 if p.updateRequestsTimer != nil {
1146 panic(p.updateRequestsTimer)
1149 if enableUpdateRequestsTimer {
1150 p.updateRequestsTimer = time.AfterFunc(math.MaxInt64, p.updateRequestsTimerFunc)
1154 const peerUpdateRequestsTimerReason = "updateRequestsTimer"
1156 func (c *Peer) updateRequestsTimerFunc() {
1158 defer c.locker().Unlock()
1159 if c.closed.IsSet() {
1162 if c.isLowOnRequests() {
1163 // If there are no outstanding requests, then a request update should have already run.
1166 if d := time.Since(c.lastRequestUpdate); d < updateRequestsTimerDuration {
1167 // These should be benign, Timer.Stop doesn't guarantee that its function won't run if it's
1168 // already been fired.
1169 torrent.Add("spurious timer requests updates", 1)
1172 c.updateRequests(peerUpdateRequestsTimerReason)
1175 // Maximum pending requests we allow peers to send us. If peer requests are buffered on read, this
1176 // instructs the amount of memory that might be used to cache pending writes. Assuming 512KiB
1177 // (1<<19) cached for sending, for 16KiB (1<<14) chunks.
1178 const localClientReqq = 1024
1180 // See the order given in Transmission's tr_peerMsgsNew.
1181 func (pc *PeerConn) sendInitialMessages() {
1184 if pc.PeerExtensionBytes.SupportsExtended() && cl.config.Extensions.SupportsExtended() {
1185 pc.write(pp.Message{
1187 ExtendedID: pp.HandshakeExtendedID,
1188 ExtendedPayload: func() []byte {
1189 msg := pp.ExtendedHandshakeMessage{
1190 V: cl.config.ExtendedHandshakeClientVersion,
1191 Reqq: localClientReqq,
1192 YourIp: pp.CompactIp(pc.remoteIp()),
1193 Encryption: cl.config.HeaderObfuscationPolicy.Preferred || !cl.config.HeaderObfuscationPolicy.RequirePreferred,
1194 Port: cl.incomingPeerPort(),
1195 MetadataSize: t.metadataSize(),
1196 // TODO: We can figure these out specific to the socket used.
1197 Ipv4: pp.CompactIp(cl.config.PublicIp4.To4()),
1198 Ipv6: cl.config.PublicIp6.To16(),
1200 msg.M = pc.LocalLtepProtocolMap.toSupportedExtensionDict()
1201 return bencode.MustMarshal(msg)
1206 if pc.fastEnabled() {
1207 if t.haveAllPieces() {
1208 pc.write(pp.Message{Type: pp.HaveAll})
1209 pc.sentHaves.AddRange(0, bitmap.BitRange(pc.t.NumPieces()))
1211 } else if !t.haveAnyPieces() {
1212 pc.write(pp.Message{Type: pp.HaveNone})
1213 pc.sentHaves.Clear()
1219 if pc.PeerExtensionBytes.SupportsDHT() && cl.config.Extensions.SupportsDHT() && cl.haveDhtServer() {
1220 pc.write(pp.Message{
1227 func (cl *Client) dhtPort() (ret uint16) {
1228 if len(cl.dhtServers) == 0 {
1231 return uint16(missinggo.AddrPort(cl.dhtServers[len(cl.dhtServers)-1].Addr()))
1234 func (cl *Client) haveDhtServer() bool {
1235 return len(cl.dhtServers) > 0
1238 // Process incoming ut_metadata message.
1239 func (cl *Client) gotMetadataExtensionMsg(payload []byte, t *Torrent, c *PeerConn) error {
1240 var d pp.ExtendedMetadataRequestMsg
1241 err := bencode.Unmarshal(payload, &d)
1242 if _, ok := err.(bencode.ErrUnusedTrailingBytes); ok {
1243 } else if err != nil {
1244 return fmt.Errorf("error unmarshalling bencode: %s", err)
1248 case pp.DataMetadataExtensionMsgType:
1249 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.MetadataChunksRead }))
1250 if !c.requestedMetadataPiece(piece) {
1251 return fmt.Errorf("got unexpected piece %d", piece)
1253 c.metadataRequests[piece] = false
1254 begin := len(payload) - d.PieceSize()
1255 if begin < 0 || begin >= len(payload) {
1256 return fmt.Errorf("data has bad offset in payload: %d", begin)
1258 t.saveMetadataPiece(piece, payload[begin:])
1259 c.lastUsefulChunkReceived = time.Now()
1260 err = t.maybeCompleteMetadata()
1262 // Log this at the Torrent-level, as we don't partition metadata by Peer yet, so we
1263 // don't know who to blame. TODO: Also errors can be returned here that aren't related
1264 // to verifying metadata, which should be fixed. This should be tagged with metadata, so
1265 // log consumers can filter for this message.
1266 t.logger.WithDefaultLevel(log.Warning).Printf("error completing metadata: %v", err)
1269 case pp.RequestMetadataExtensionMsgType:
1270 if !t.haveMetadataPiece(piece) {
1271 c.write(t.newMetadataExtensionMessage(c, pp.RejectMetadataExtensionMsgType, d.Piece, nil))
1274 start := (1 << 14) * piece
1275 c.protocolLogger.WithDefaultLevel(log.Debug).Printf("sending metadata piece %d", piece)
1276 c.write(t.newMetadataExtensionMessage(c, pp.DataMetadataExtensionMsgType, piece, t.metadataBytes[start:start+t.metadataPieceSize(piece)]))
1278 case pp.RejectMetadataExtensionMsgType:
1281 return errors.New("unknown msg_type value")
1285 func (cl *Client) badPeerAddr(addr PeerRemoteAddr) bool {
1286 if ipa, ok := tryIpPortFromNetAddr(addr); ok {
1287 return cl.badPeerIPPort(ipa.IP, ipa.Port)
1292 // Returns whether the IP address and port are considered "bad".
1293 func (cl *Client) badPeerIPPort(ip net.IP, port int) bool {
1294 if port == 0 || ip == nil {
1297 if cl.dopplegangerAddr(net.JoinHostPort(ip.String(), strconv.FormatInt(int64(port), 10))) {
1300 if _, ok := cl.ipBlockRange(ip); ok {
1303 ipAddr, ok := netip.AddrFromSlice(ip)
1307 if _, ok := cl.badPeerIPs[ipAddr]; ok {
1313 // Return a Torrent ready for insertion into a Client.
1314 func (cl *Client) newTorrent(ih metainfo.Hash, specStorage storage.ClientImpl) (t *Torrent) {
1315 return cl.newTorrentOpt(AddTorrentOpts{
1317 Storage: specStorage,
1321 // Return a Torrent ready for insertion into a Client.
1322 func (cl *Client) newTorrentOpt(opts AddTorrentOpts) (t *Torrent) {
1323 var v1InfoHash g.Option[infohash.T]
1324 if !opts.InfoHash.IsZero() {
1325 v1InfoHash.Set(opts.InfoHash)
1327 if !v1InfoHash.Ok && !opts.InfoHashV2.Ok {
1328 panic("v1 infohash must be nonzero or v2 infohash must be set")
1330 // use provided storage, if provided
1331 storageClient := cl.defaultStorage
1332 if opts.Storage != nil {
1333 storageClient = storage.NewClient(opts.Storage)
1338 infoHash: v1InfoHash,
1339 infoHashV2: opts.InfoHashV2,
1340 peers: prioritizedPeers{
1342 getPrio: func(p PeerInfo) peerPriority {
1344 return bep40PriorityIgnoreError(cl.publicAddr(ipPort.IP), ipPort)
1347 conns: make(map[*PeerConn]struct{}, 2*cl.config.EstablishedConnsPerTorrent),
1349 storageOpener: storageClient,
1350 maxEstablishedConns: cl.config.EstablishedConnsPerTorrent,
1352 metadataChanged: sync.Cond{
1355 webSeeds: make(map[string]*Peer),
1356 gotMetainfoC: make(chan struct{}),
1360 t.smartBanCache.Hash = func(b []byte) uint64 {
1366 t.smartBanCache.Init()
1367 t.networkingEnabled.Set()
1368 t.logger = cl.logger.WithDefaultLevel(log.Debug)
1369 t.sourcesLogger = t.logger.WithNames("sources")
1370 if opts.ChunkSize == 0 {
1371 opts.ChunkSize = defaultChunkSize
1373 t.setChunkSize(opts.ChunkSize)
1377 // A file-like handle to some torrent data resource.
1378 type Handle interface {
1385 func (cl *Client) AddTorrentInfoHash(infoHash metainfo.Hash) (t *Torrent, new bool) {
1386 return cl.AddTorrentInfoHashWithStorage(infoHash, nil)
1389 // Deprecated. Adds a torrent by InfoHash with a custom Storage implementation.
1390 // If the torrent already exists then this Storage is ignored and the
1391 // existing torrent returned with `new` set to `false`
1392 func (cl *Client) AddTorrentInfoHashWithStorage(
1393 infoHash metainfo.Hash,
1394 specStorage storage.ClientImpl,
1395 ) (t *Torrent, new bool) {
1398 t, ok := cl.torrentsByShortHash[infoHash]
1404 t = cl.newTorrent(infoHash, specStorage)
1405 cl.eachDhtServer(func(s DhtServer) {
1406 if cl.config.PeriodicallyAnnounceTorrentsToDht {
1407 go t.dhtAnnouncer(s)
1410 cl.torrentsByShortHash[infoHash] = t
1411 cl.torrents[t] = struct{}{}
1412 cl.clearAcceptLimits()
1413 t.updateWantPeersEvent()
1414 // Tickle Client.waitAccept, new torrent may want conns.
1415 cl.event.Broadcast()
1419 // Adds a torrent by InfoHash with a custom Storage implementation. If the torrent already exists
1420 // then this Storage is ignored and the existing torrent returned with `new` set to `false`.
1421 func (cl *Client) AddTorrentOpt(opts AddTorrentOpts) (t *Torrent, new bool) {
1422 infoHash := opts.InfoHash
1425 t, ok := cl.torrentsByShortHash[infoHash]
1429 if opts.InfoHashV2.Ok {
1430 t, ok = cl.torrentsByShortHash[*opts.InfoHashV2.Value.ToShort()]
1437 t = cl.newTorrentOpt(opts)
1438 cl.eachDhtServer(func(s DhtServer) {
1439 if cl.config.PeriodicallyAnnounceTorrentsToDht {
1440 go t.dhtAnnouncer(s)
1443 cl.torrentsByShortHash[infoHash] = t
1444 cl.torrents[t] = struct{}{}
1445 t.setInfoBytesLocked(opts.InfoBytes)
1446 cl.clearAcceptLimits()
1447 t.updateWantPeersEvent()
1448 // Tickle Client.waitAccept, new torrent may want conns.
1449 cl.event.Broadcast()
1453 type AddTorrentOpts struct {
1455 InfoHashV2 g.Option[infohash_v2.T]
1456 Storage storage.ClientImpl
1457 ChunkSize pp.Integer
1461 // Add or merge a torrent spec. Returns new if the torrent wasn't already in the client. See also
1462 // Torrent.MergeSpec.
1463 func (cl *Client) AddTorrentSpec(spec *TorrentSpec) (t *Torrent, new bool, err error) {
1464 t, new = cl.AddTorrentOpt(AddTorrentOpts{
1465 InfoHash: spec.InfoHash,
1466 InfoHashV2: spec.InfoHashV2,
1467 Storage: spec.Storage,
1468 ChunkSize: spec.ChunkSize,
1472 // ChunkSize was already applied by adding a new Torrent, and MergeSpec disallows changing
1474 modSpec.ChunkSize = 0
1476 err = t.MergeSpec(&modSpec)
1477 if err != nil && new {
1483 // The trackers will be merged with the existing ones. If the Info isn't yet known, it will be set.
1484 // spec.DisallowDataDownload/Upload will be read and applied
1485 // The display name is replaced if the new spec provides one. Note that any `Storage` is ignored.
1486 func (t *Torrent) MergeSpec(spec *TorrentSpec) error {
1487 if spec.DisplayName != "" {
1488 t.SetDisplayName(spec.DisplayName)
1490 if spec.InfoBytes != nil {
1491 err := t.SetInfoBytes(spec.InfoBytes)
1497 cl.AddDhtNodes(spec.DhtNodes)
1498 t.UseSources(spec.Sources)
1501 t.initialPieceCheckDisabled = spec.DisableInitialPieceCheck
1502 for _, url := range spec.Webseeds {
1505 for _, peerAddr := range spec.PeerAddrs {
1507 Addr: StringAddr(peerAddr),
1508 Source: PeerSourceDirect,
1512 if spec.ChunkSize != 0 {
1513 panic("chunk size cannot be changed for existing Torrent")
1515 t.addTrackers(spec.Trackers)
1517 t.dataDownloadDisallowed.SetBool(spec.DisallowDataDownload)
1518 t.dataUploadDisallowed = spec.DisallowDataUpload
1519 return errors.Join(t.addPieceLayersLocked(spec.PieceLayers)...)
1522 func (cl *Client) dropTorrent(t *Torrent, wg *sync.WaitGroup) (err error) {
1523 t.eachShortInfohash(func(short [20]byte) {
1524 delete(cl.torrentsByShortHash, short)
1527 delete(cl.torrents, t)
1531 func (cl *Client) allTorrentsCompleted() bool {
1532 for t := range cl.torrents {
1536 if !t.haveAllPieces() {
1543 // Returns true when all torrents are completely downloaded and false if the
1544 // client is stopped before that.
1545 func (cl *Client) WaitAll() bool {
1548 for !cl.allTorrentsCompleted() {
1549 if cl.closed.IsSet() {
1557 // Returns handles to all the torrents loaded in the Client.
1558 func (cl *Client) Torrents() []*Torrent {
1561 return cl.torrentsAsSlice()
1564 func (cl *Client) torrentsAsSlice() (ret []*Torrent) {
1565 for t := range cl.torrents {
1566 ret = append(ret, t)
1571 func (cl *Client) AddMagnet(uri string) (T *Torrent, err error) {
1572 spec, err := TorrentSpecFromMagnetUri(uri)
1576 T, _, err = cl.AddTorrentSpec(spec)
1580 func (cl *Client) AddTorrent(mi *metainfo.MetaInfo) (T *Torrent, err error) {
1581 ts, err := TorrentSpecFromMetaInfoErr(mi)
1585 T, _, err = cl.AddTorrentSpec(ts)
1589 func (cl *Client) AddTorrentFromFile(filename string) (T *Torrent, err error) {
1590 mi, err := metainfo.LoadFromFile(filename)
1594 return cl.AddTorrent(mi)
1597 func (cl *Client) DhtServers() []DhtServer {
1598 return cl.dhtServers
1601 func (cl *Client) AddDhtNodes(nodes []string) {
1602 for _, n := range nodes {
1603 hmp := missinggo.SplitHostMaybePort(n)
1604 ip := net.ParseIP(hmp.Host)
1606 cl.logger.Printf("won't add DHT node with bad IP: %q", hmp.Host)
1609 ni := krpc.NodeInfo{
1610 Addr: krpc.NodeAddr{
1615 cl.eachDhtServer(func(s DhtServer) {
1621 func (cl *Client) banPeerIP(ip net.IP) {
1622 // We can't take this from string, because it will lose netip's v4on6. net.ParseIP parses v4
1623 // addresses directly to v4on6, which doesn't compare equal with v4.
1624 ipAddr, ok := netip.AddrFromSlice(ip)
1628 g.MakeMapIfNilAndSet(&cl.badPeerIPs, ipAddr, struct{}{})
1629 for t := range cl.torrents {
1630 t.iterPeers(func(p *Peer) {
1631 if p.remoteIp().Equal(ip) {
1632 t.logger.Levelf(log.Warning, "dropping peer %v with banned ip %v", p, ip)
1633 // Should this be a close?
1640 type newConnectionOpts struct {
1642 remoteAddr PeerRemoteAddr
1643 localPublicAddr peerLocalPublicAddr
1648 func (cl *Client) newConnection(nc net.Conn, opts newConnectionOpts) (c *PeerConn) {
1649 if opts.network == "" {
1650 panic(opts.remoteAddr)
1654 outgoing: opts.outgoing,
1657 PeerMaxRequests: 250,
1659 RemoteAddr: opts.remoteAddr,
1660 localPublicAddr: opts.localPublicAddr,
1661 Network: opts.network,
1662 callbacks: &cl.config.Callbacks,
1664 connString: opts.connString,
1667 c.peerRequestDataAllocLimiter.Max = cl.config.MaxAllocPeerRequestDataPerConn
1668 c.initRequestState()
1669 // TODO: Need to be much more explicit about this, including allowing non-IP bannable addresses.
1670 if opts.remoteAddr != nil {
1671 netipAddrPort, err := netip.ParseAddrPort(opts.remoteAddr.String())
1673 c.bannableAddr = Some(netipAddrPort.Addr())
1677 c.logger = cl.logger.WithDefaultLevel(log.Warning).WithContextText(fmt.Sprintf("%T %p", c, c))
1678 c.protocolLogger = c.logger.WithNames(protocolLoggingName)
1679 c.setRW(connStatsReadWriter{nc, c})
1680 c.r = &rateLimitedReader{
1681 l: cl.config.DownloadRateLimiter,
1686 "inited with remoteAddr %v network %v outgoing %t",
1687 opts.remoteAddr, opts.network, opts.outgoing,
1689 for _, f := range cl.config.Callbacks.NewPeer {
1695 func (cl *Client) onDHTAnnouncePeer(ih metainfo.Hash, ip net.IP, port int, portOk bool) {
1698 t := cl.torrentsByShortHash[ih]
1702 t.addPeers([]PeerInfo{{
1703 Addr: ipPortAddr{ip, port},
1704 Source: PeerSourceDhtAnnouncePeer,
1708 func firstNotNil(ips ...net.IP) net.IP {
1709 for _, ip := range ips {
1717 func (cl *Client) eachListener(f func(Listener) bool) {
1718 for _, s := range cl.listeners {
1725 func (cl *Client) findListener(f func(Listener) bool) (ret Listener) {
1726 for i := 0; i < len(cl.listeners); i += 1 {
1727 if ret = cl.listeners[i]; f(ret) {
1734 func (cl *Client) publicIp(peer net.IP) net.IP {
1735 // TODO: Use BEP 10 to determine how peers are seeing us.
1736 if peer.To4() != nil {
1738 cl.config.PublicIp4,
1739 cl.findListenerIp(func(ip net.IP) bool { return ip.To4() != nil }),
1744 cl.config.PublicIp6,
1745 cl.findListenerIp(func(ip net.IP) bool { return ip.To4() == nil }),
1749 func (cl *Client) findListenerIp(f func(net.IP) bool) net.IP {
1750 l := cl.findListener(
1751 func(l Listener) bool {
1752 return f(addrIpOrNil(l.Addr()))
1758 return addrIpOrNil(l.Addr())
1761 // Our IP as a peer should see it.
1762 func (cl *Client) publicAddr(peer net.IP) IpPort {
1763 return IpPort{IP: cl.publicIp(peer), Port: uint16(cl.incomingPeerPort())}
1766 // ListenAddrs addresses currently being listened to.
1767 func (cl *Client) ListenAddrs() (ret []net.Addr) {
1769 ret = make([]net.Addr, len(cl.listeners))
1770 for i := 0; i < len(cl.listeners); i += 1 {
1771 ret[i] = cl.listeners[i].Addr()
1777 func (cl *Client) PublicIPs() (ips []net.IP) {
1778 if ip := cl.config.PublicIp4; ip != nil {
1779 ips = append(ips, ip)
1781 if ip := cl.config.PublicIp6; ip != nil {
1782 ips = append(ips, ip)
1787 func (cl *Client) onBadAccept(addr PeerRemoteAddr) {
1788 ipa, ok := tryIpPortFromNetAddr(addr)
1792 ip := maskIpForAcceptLimiting(ipa.IP)
1793 if cl.acceptLimiter == nil {
1794 cl.acceptLimiter = make(map[ipStr]int)
1796 cl.acceptLimiter[ipStr(ip.String())]++
1799 func maskIpForAcceptLimiting(ip net.IP) net.IP {
1800 if ip4 := ip.To4(); ip4 != nil {
1801 return ip4.Mask(net.CIDRMask(24, 32))
1806 func (cl *Client) clearAcceptLimits() {
1807 cl.acceptLimiter = nil
1810 func (cl *Client) acceptLimitClearer() {
1813 case <-cl.closed.Done():
1815 case <-time.After(15 * time.Minute):
1817 cl.clearAcceptLimits()
1823 func (cl *Client) rateLimitAccept(ip net.IP) bool {
1824 if cl.config.DisableAcceptRateLimiting {
1827 return cl.acceptLimiter[ipStr(maskIpForAcceptLimiting(ip).String())] > 0
1830 func (cl *Client) rLock() {
1834 func (cl *Client) rUnlock() {
1838 func (cl *Client) lock() {
1842 func (cl *Client) unlock() {
1846 func (cl *Client) locker() *lockWithDeferreds {
1850 func (cl *Client) String() string {
1851 return fmt.Sprintf("<%[1]T %[1]p>", cl)
1854 func (cl *Client) ICEServers() []webrtc.ICEServer {
1855 var ICEServers []webrtc.ICEServer
1856 if cl.config.ICEServerList != nil {
1857 ICEServers = cl.config.ICEServerList
1858 } else if cl.config.ICEServers != nil {
1859 ICEServers = []webrtc.ICEServer{{URLs: cl.config.ICEServers}}
1864 // Returns connection-level aggregate connStats at the Client level. See the comment on
1865 // TorrentStats.ConnStats.
1866 func (cl *Client) ConnStats() ConnStats {
1867 return cl.connStats.Copy()
1870 func (cl *Client) Stats() ClientStats {
1873 return cl.statsLocked()