21 "github.com/RoaringBitmap/roaring"
22 "github.com/anacrolix/chansync"
23 "github.com/anacrolix/chansync/events"
24 "github.com/anacrolix/dht/v2"
25 . "github.com/anacrolix/generics"
26 g "github.com/anacrolix/generics"
27 "github.com/anacrolix/log"
28 "github.com/anacrolix/missinggo/slices"
29 "github.com/anacrolix/missinggo/v2"
30 "github.com/anacrolix/missinggo/v2/bitmap"
31 "github.com/anacrolix/missinggo/v2/pubsub"
32 "github.com/anacrolix/multiless"
33 "github.com/anacrolix/sync"
34 "github.com/pion/datachannel"
35 "golang.org/x/exp/maps"
36 "golang.org/x/sync/errgroup"
38 "github.com/anacrolix/torrent/bencode"
39 "github.com/anacrolix/torrent/internal/check"
40 "github.com/anacrolix/torrent/internal/nestedmaps"
41 "github.com/anacrolix/torrent/merkle"
42 "github.com/anacrolix/torrent/metainfo"
43 pp "github.com/anacrolix/torrent/peer_protocol"
44 utHolepunch "github.com/anacrolix/torrent/peer_protocol/ut-holepunch"
45 request_strategy "github.com/anacrolix/torrent/request-strategy"
46 "github.com/anacrolix/torrent/storage"
47 "github.com/anacrolix/torrent/tracker"
48 typedRoaring "github.com/anacrolix/torrent/typed-roaring"
49 "github.com/anacrolix/torrent/types/infohash"
50 infohash_v2 "github.com/anacrolix/torrent/types/infohash-v2"
51 "github.com/anacrolix/torrent/webseed"
52 "github.com/anacrolix/torrent/webtorrent"
55 // Maintains state of torrent within a Client. Many methods should not be called before the info is
56 // available, see .Info and .GotInfo.
58 // Torrent-level aggregate statistics. First in struct to ensure 64-bit
59 // alignment. See #262.
64 networkingEnabled chansync.Flag
65 dataDownloadDisallowed chansync.Flag
66 dataUploadDisallowed bool
67 userOnWriteChunkErr func(error)
69 closed chansync.SetOnce
72 infoHash g.Option[metainfo.Hash]
73 infoHashV2 g.Option[infohash_v2.T]
77 // The order pieces are requested if there's no stronger reason like availability or priority.
78 pieceRequestOrder []int
79 // Values are the piece indices that changed.
80 pieceStateChanges pubsub.PubSub[PieceStateChange]
81 // The size of chunks to request from peers over the wire. This is
82 // normally 16KiB by convention these days.
85 // Total length of the torrent in bytes. Stored because it's not O(1) to
86 // get this from the info dict.
89 // The storage to open when the info dict becomes available.
90 storageOpener *storage.Client
91 // Storage for torrent data.
92 storage *storage.Torrent
93 // Read-locked for using storage, and write-locked for Closing.
94 storageLock sync.RWMutex
96 // TODO: Only announce stuff is used?
97 metainfo metainfo.MetaInfo
99 // The info dict. nil if we don't have it (yet).
103 _chunksPerRegularPiece chunkIndexType
105 webSeeds map[string]*Peer
106 // Active peer connections, running message stream loops. TODO: Make this
107 // open (not-closed) connections only.
108 conns map[*PeerConn]struct{}
109 maxEstablishedConns int
110 // Set of addrs to which we're attempting to connect. Connections are
111 // half-open until all handshakes are completed.
112 halfOpen map[string]map[outgoingConnAttemptKey]*PeerInfo
114 // Reserve of peers to connect to. A peer can be both here and in the
115 // active connections if were told about the peer after connecting with
116 // them. That encourages us to reconnect to peers that are well known in
118 peers prioritizedPeers
119 // Whether we want to know more peers.
120 wantPeersEvent missinggo.Event
121 // An announcer for each tracker URL.
122 trackerAnnouncers map[torrentTrackerAnnouncerKey]torrentTrackerAnnouncer
123 // How many times we've initiated a DHT announce. TODO: Move into stats.
126 // Name used if the info name isn't available. Should be cleared when the
127 // Info does become available.
131 // The bencoded bytes of the info dict. This is actively manipulated if
132 // the info bytes aren't initially available, and we try to fetch them
135 // Each element corresponds to the 16KiB metadata pieces. If true, we have
136 // received that piece.
137 metadataCompletedChunks []bool
138 metadataChanged sync.Cond
140 // Closed when .Info is obtained.
141 gotMetainfoC chan struct{}
143 readers map[*reader]struct{}
144 _readerNowPieces bitmap.Bitmap
145 _readerReadaheadPieces bitmap.Bitmap
147 // A cache of pieces we need to get. Calculated from various piece and file priorities and
148 // completion states elsewhere. Includes piece data and piece v2 hashes.
149 _pendingPieces roaring.Bitmap
150 // A cache of completed piece indices.
151 _completedPieces roaring.Bitmap
152 // Pieces that need to be hashed.
153 piecesQueuedForHash bitmap.Bitmap
154 activePieceHashes int
155 initialPieceCheckDisabled bool
157 connsWithAllPieces map[*Peer]struct{}
159 requestState map[RequestIndex]requestState
160 // Chunks we've written to since the corresponding piece was last checked.
161 dirtyChunks typedRoaring.Bitmap[RequestIndex]
165 // Is On when all pieces are complete.
166 Complete chansync.Flag
168 // Torrent sources in use keyed by the source string.
169 activeSources sync.Map
170 sourcesLogger log.Logger
172 smartBanCache smartBanCache
174 // Large allocations reused between request state updates.
175 requestPieceStates []request_strategy.PieceRequestOrderState
176 requestIndexes []RequestIndex
181 type torrentTrackerAnnouncerKey struct {
182 shortInfohash [20]byte
186 type outgoingConnAttemptKey = *PeerInfo
188 func (t *Torrent) length() int64 {
189 return t._length.Value
192 func (t *Torrent) selectivePieceAvailabilityFromPeers(i pieceIndex) (count int) {
193 // This could be done with roaring.BitSliceIndexing.
194 t.iterPeers(func(peer *Peer) {
195 if _, ok := t.connsWithAllPieces[peer]; ok {
198 if peer.peerHasPiece(i) {
205 func (t *Torrent) decPieceAvailability(i pieceIndex) {
210 if p.relativeAvailability <= 0 {
211 panic(p.relativeAvailability)
213 p.relativeAvailability--
214 t.updatePieceRequestOrderPiece(i)
217 func (t *Torrent) incPieceAvailability(i pieceIndex) {
218 // If we don't the info, this should be reconciled when we do.
221 p.relativeAvailability++
222 t.updatePieceRequestOrderPiece(i)
226 func (t *Torrent) readerNowPieces() bitmap.Bitmap {
227 return t._readerNowPieces
230 func (t *Torrent) readerReadaheadPieces() bitmap.Bitmap {
231 return t._readerReadaheadPieces
234 func (t *Torrent) ignorePieceForRequests(i pieceIndex) bool {
235 return t.piece(i).ignoreForRequests()
238 // Returns a channel that is closed when the Torrent is closed.
239 func (t *Torrent) Closed() events.Done {
240 return t.closed.Done()
243 // KnownSwarm returns the known subset of the peers in the Torrent's swarm, including active,
244 // pending, and half-open peers.
245 func (t *Torrent) KnownSwarm() (ks []PeerInfo) {
246 // Add pending peers to the list
247 t.peers.Each(func(peer PeerInfo) {
248 ks = append(ks, peer)
251 // Add half-open peers to the list
252 for _, attempts := range t.halfOpen {
253 for _, peer := range attempts {
254 ks = append(ks, *peer)
258 // Add active peers to the list
261 for conn := range t.conns {
262 ks = append(ks, PeerInfo{
264 Addr: conn.RemoteAddr,
265 Source: conn.Discovery,
266 // > If the connection is encrypted, that's certainly enough to set SupportsEncryption.
267 // > But if we're not connected to them with an encrypted connection, I couldn't say
268 // > what's appropriate. We can carry forward the SupportsEncryption value as we
269 // > received it from trackers/DHT/PEX, or just use the encryption state for the
270 // > connection. It's probably easiest to do the latter for now.
271 // https://github.com/anacrolix/torrent/pull/188
272 SupportsEncryption: conn.headerEncrypted,
279 func (t *Torrent) setChunkSize(size pp.Integer) {
281 t.chunkPool = sync.Pool{
282 New: func() interface{} {
283 b := make([]byte, size)
289 func (t *Torrent) pieceComplete(piece pieceIndex) bool {
290 return t._completedPieces.Contains(bitmap.BitIndex(piece))
293 func (t *Torrent) pieceCompleteUncached(piece pieceIndex) storage.Completion {
294 if t.storage == nil {
295 return storage.Completion{Complete: false, Ok: true}
297 return t.pieces[piece].Storage().Completion()
300 // There's a connection to that address already.
301 func (t *Torrent) addrActive(addr string) bool {
302 if _, ok := t.halfOpen[addr]; ok {
305 for c := range t.conns {
307 if ra.String() == addr {
314 func (t *Torrent) appendUnclosedConns(ret []*PeerConn) []*PeerConn {
315 return t.appendConns(ret, func(conn *PeerConn) bool {
316 return !conn.closed.IsSet()
320 func (t *Torrent) appendConns(ret []*PeerConn, f func(*PeerConn) bool) []*PeerConn {
321 for c := range t.conns {
329 func (t *Torrent) addPeer(p PeerInfo) (added bool) {
331 torrent.Add(fmt.Sprintf("peers added by source %q", p.Source), 1)
332 if t.closed.IsSet() {
335 if ipAddr, ok := tryIpPortFromNetAddr(p.Addr); ok {
336 if cl.badPeerIPPort(ipAddr.IP, ipAddr.Port) {
337 torrent.Add("peers not added because of bad addr", 1)
338 // cl.logger.Printf("peers not added because of bad addr: %v", p)
342 if replaced, ok := t.peers.AddReturningReplacedPeer(p); ok {
343 torrent.Add("peers replaced", 1)
344 if !replaced.equal(p) {
345 t.logger.WithDefaultLevel(log.Debug).Printf("added %v replacing %v", p, replaced)
352 for t.peers.Len() > cl.config.TorrentPeersHighWater {
353 _, ok := t.peers.DeleteMin()
355 torrent.Add("excess reserve peers discarded", 1)
361 func (t *Torrent) invalidateMetadata() {
362 for i := 0; i < len(t.metadataCompletedChunks); i++ {
363 t.metadataCompletedChunks[i] = false
370 func (t *Torrent) saveMetadataPiece(index int, data []byte) {
374 if index >= len(t.metadataCompletedChunks) {
375 t.logger.Printf("%s: ignoring metadata piece %d", t, index)
378 copy(t.metadataBytes[(1<<14)*index:], data)
379 t.metadataCompletedChunks[index] = true
382 func (t *Torrent) metadataPieceCount() int {
383 return (len(t.metadataBytes) + (1 << 14) - 1) / (1 << 14)
386 func (t *Torrent) haveMetadataPiece(piece int) bool {
388 return (1<<14)*piece < len(t.metadataBytes)
390 return piece < len(t.metadataCompletedChunks) && t.metadataCompletedChunks[piece]
394 func (t *Torrent) metadataSize() int {
395 return len(t.metadataBytes)
398 func (t *Torrent) makePieces() {
399 t.pieces = make([]Piece, t.info.NumPieces())
400 for i := range t.pieces {
401 piece := &t.pieces[i]
404 piece.noPendingWrites.L = &piece.pendingWritesMutex
406 piece.hash = (*metainfo.Hash)(unsafe.Pointer(
407 unsafe.SliceData(t.info.Pieces[i*sha1.Size : (i+1)*sha1.Size])))
410 beginFile := pieceFirstFileIndex(piece.torrentBeginOffset(), files)
411 endFile := pieceEndFileIndex(piece.torrentEndOffset(), files)
412 piece.files = files[beginFile:endFile]
413 if t.info.FilesArePieceAligned() {
414 numFiles := len(piece.files)
416 panic(fmt.Sprintf("%v:%v", beginFile, endFile))
419 file := piece.mustGetOnlyFile()
420 if file.numPieces() == 1 {
421 piece.hashV2.Set(file.piecesRoot.Unwrap())
428 func (t *Torrent) addPieceLayersLocked(layers map[string]string) (errs []error) {
433 for _, f := range *t.files {
434 if !f.piecesRoot.Ok {
435 err := fmt.Errorf("no piece root set for file %v", f)
436 errs = append(errs, err)
439 compactLayer, ok := layers[string(f.piecesRoot.Value[:])]
440 var hashes [][32]byte
443 hashes, err = merkle.CompactLayerToSliceHashes(compactLayer)
445 err = fmt.Errorf("bad piece layers for file %q: %w", f, err)
446 errs = append(errs, err)
449 } else if f.length > t.info.PieceLength {
450 // BEP 52 is pretty strongly worded about this, even though we should be able to
451 // recover: If a v2 torrent is added by magnet link or infohash, we need to fetch piece
452 // layers ourselves anyway, and that's how we can recover from this.
453 t.logger.Levelf(log.Warning, "no piece layers for file %q", f)
456 hashes = [][32]byte{f.piecesRoot.Value}
458 if len(hashes) != f.numPieces() {
461 fmt.Errorf("file %q: got %v hashes expected %v", f, len(hashes), f.numPieces()),
465 root := merkle.RootWithPadHash(hashes, metainfo.HashForPiecePad(t.info.PieceLength))
466 if root != f.piecesRoot.Value {
467 errs = append(errs, fmt.Errorf("%v: expected hash %x got %x", f, f.piecesRoot.Value, root))
470 for i := range f.numPieces() {
471 pi := f.BeginPieceIndex() + i
473 p.setV2Hash(hashes[i])
479 func (t *Torrent) AddPieceLayers(layers map[string]string) (errs []error) {
482 return t.addPieceLayersLocked(layers)
485 // Returns the index of the first file containing the piece. files must be
486 // ordered by offset.
487 func pieceFirstFileIndex(pieceOffset int64, files []*File) int {
488 for i, f := range files {
489 if f.offset+f.length > pieceOffset {
496 // Returns the index after the last file containing the piece. files must be
497 // ordered by offset.
498 func pieceEndFileIndex(pieceEndOffset int64, files []*File) int {
499 for i, f := range files {
500 if f.offset >= pieceEndOffset {
507 func (t *Torrent) cacheLength() {
509 for _, f := range t.info.UpvertedFiles() {
515 // TODO: This shouldn't fail for storage reasons. Instead we should handle storage failure
517 func (t *Torrent) setInfo(info *metainfo.Info) error {
518 if err := validateInfo(info); err != nil {
519 return fmt.Errorf("bad info: %s", err)
521 if t.storageOpener != nil {
523 t.storage, err = t.storageOpener.OpenTorrent(info, *t.canonicalShortInfohash())
525 return fmt.Errorf("error opening torrent storage: %s", err)
531 t._chunksPerRegularPiece = chunkIndexType((pp.Integer(t.usualPieceSize()) + t.chunkSize - 1) / t.chunkSize)
533 t.displayName = "" // Save a few bytes lol.
540 func (t *Torrent) pieceRequestOrderKey(i int) request_strategy.PieceRequestOrderKey {
541 return request_strategy.PieceRequestOrderKey{
542 InfoHash: *t.canonicalShortInfohash(),
547 // This seems to be all the follow-up tasks after info is set, that can't fail.
548 func (t *Torrent) onSetInfo() {
549 t.pieceRequestOrder = rand.Perm(t.numPieces())
550 t.initPieceRequestOrder()
551 MakeSliceWithLength(&t.requestPieceStates, t.numPieces())
552 for i := range t.pieces {
554 // Need to add relativeAvailability before updating piece completion, as that may result in conns
556 if p.relativeAvailability != 0 {
557 panic(p.relativeAvailability)
559 p.relativeAvailability = t.selectivePieceAvailabilityFromPeers(i)
560 t.addRequestOrderPiece(i)
561 t.updatePieceCompletion(i)
562 t.queueInitialPieceCheck(i)
564 t.cl.event.Broadcast()
565 close(t.gotMetainfoC)
566 t.updateWantPeersEvent()
567 t.requestState = make(map[RequestIndex]requestState)
568 t.tryCreateMorePieceHashers()
569 t.iterPeers(func(p *Peer) {
571 p.updateRequests("onSetInfo")
575 // Checks the info bytes hash to expected values. Fills in any missing infohashes.
576 func (t *Torrent) hashInfoBytes(b []byte, info *metainfo.Info) error {
577 v1Hash := infohash.HashBytes(b)
578 v2Hash := infohash_v2.HashBytes(b)
580 if t.infoHash.Ok && !t.infoHashV2.Ok {
581 if v1Hash == t.infoHash.Value {
583 t.infoHashV2.Set(v2Hash)
584 cl.torrentsByShortHash[*v2Hash.ToShort()] = t
586 } else if *v2Hash.ToShort() == t.infoHash.Value {
588 return errors.New("invalid v2 info")
590 t.infoHashV2.Set(v2Hash)
593 cl.torrentsByShortHash[v1Hash] = t
594 t.infoHash.Set(v1Hash)
597 } else if t.infoHash.Ok && t.infoHashV2.Ok {
598 if v1Hash != t.infoHash.Value {
599 return errors.New("incorrect v1 infohash")
601 if v2Hash != t.infoHashV2.Value {
602 return errors.New("incorrect v2 infohash")
604 } else if !t.infoHash.Ok && t.infoHashV2.Ok {
605 if v2Hash != t.infoHashV2.Value {
606 return errors.New("incorrect v2 infohash")
609 t.infoHash.Set(v1Hash)
610 cl.torrentsByShortHash[v1Hash] = t
613 panic("no expected infohashes")
618 // Called when metadata for a torrent becomes available.
619 func (t *Torrent) setInfoBytesLocked(b []byte) (err error) {
620 var info metainfo.Info
621 err = bencode.Unmarshal(b, &info)
623 err = fmt.Errorf("unmarshalling info bytes: %w", err)
626 err = t.hashInfoBytes(b, &info)
631 t.metadataCompletedChunks = nil
635 if err := t.setInfo(&info); err != nil {
642 func (t *Torrent) haveAllMetadataPieces() bool {
646 if t.metadataCompletedChunks == nil {
649 for _, have := range t.metadataCompletedChunks {
657 // TODO: Propagate errors to disconnect peer.
658 func (t *Torrent) setMetadataSize(size int) (err error) {
660 // We already know the correct metadata size.
663 if uint32(size) > maxMetadataSize {
664 return log.WithLevel(log.Warning, errors.New("bad size"))
666 if len(t.metadataBytes) == size {
669 t.metadataBytes = make([]byte, size)
670 t.metadataCompletedChunks = make([]bool, (size+(1<<14)-1)/(1<<14))
671 t.metadataChanged.Broadcast()
672 for c := range t.conns {
673 c.requestPendingMetadata()
678 // The current working name for the torrent. Either the name in the info dict,
679 // or a display name given such as by the dn value in a magnet link, or "".
680 func (t *Torrent) name() string {
682 defer t.nameMu.RUnlock()
684 return t.info.BestName()
686 if t.displayName != "" {
689 return "infohash:" + t.canonicalShortInfohash().HexString()
692 func (t *Torrent) pieceState(index pieceIndex) (ret PieceState) {
693 p := &t.pieces[index]
694 ret.Priority = p.effectivePriority()
695 ret.Completion = p.completion()
696 ret.QueuedForHash = p.queuedForHash()
697 ret.Hashing = p.hashing
698 ret.Checking = ret.QueuedForHash || ret.Hashing
699 ret.Marking = p.marking
700 if !ret.Complete && t.piecePartiallyDownloaded(index) {
703 if t.info.HasV2() && !p.hashV2.Ok {
704 ret.MissingPieceLayerHash = true
709 func (t *Torrent) metadataPieceSize(piece int) int {
710 return metadataPieceSize(len(t.metadataBytes), piece)
713 func (t *Torrent) newMetadataExtensionMessage(c *PeerConn, msgType pp.ExtendedMetadataRequestMsgType, piece int, data []byte) pp.Message {
716 ExtendedID: c.PeerExtensionIDs[pp.ExtensionNameMetadata],
717 ExtendedPayload: append(bencode.MustMarshal(pp.ExtendedMetadataRequestMsg{
719 TotalSize: len(t.metadataBytes),
725 type pieceAvailabilityRun struct {
730 func (me pieceAvailabilityRun) String() string {
731 return fmt.Sprintf("%v(%v)", me.Count, me.Availability)
734 func (t *Torrent) pieceAvailabilityRuns() (ret []pieceAvailabilityRun) {
735 rle := missinggo.NewRunLengthEncoder(func(el interface{}, count uint64) {
736 ret = append(ret, pieceAvailabilityRun{Availability: el.(int), Count: int(count)})
738 for i := range t.pieces {
739 rle.Append(t.pieces[i].availability(), 1)
745 func (t *Torrent) pieceAvailabilityFrequencies() (freqs []int) {
746 freqs = make([]int, t.numActivePeers()+1)
747 for i := range t.pieces {
748 freqs[t.piece(i).availability()]++
753 func (t *Torrent) pieceStateRuns() (ret PieceStateRuns) {
754 rle := missinggo.NewRunLengthEncoder(func(el interface{}, count uint64) {
755 ret = append(ret, PieceStateRun{
756 PieceState: el.(PieceState),
760 for index := range t.pieces {
761 rle.Append(t.pieceState(index), 1)
767 // Produces a small string representing a PieceStateRun.
768 func (psr PieceStateRun) String() (ret string) {
769 ret = fmt.Sprintf("%d", psr.Length)
770 ret += func() string {
771 switch psr.Priority {
772 case PiecePriorityNext:
774 case PiecePriorityNormal:
776 case PiecePriorityReadahead:
778 case PiecePriorityNow:
780 case PiecePriorityHigh:
789 if psr.QueuedForHash {
804 if psr.MissingPieceLayerHash {
810 func (t *Torrent) writeStatus(w io.Writer) {
812 fmt.Fprintf(w, "Infohash: %s\n", t.infoHash.Value.HexString())
815 fmt.Fprintf(w, "Infohash v2: %s\n", t.infoHashV2.Value.HexString())
817 fmt.Fprintf(w, "Metadata length: %d\n", t.metadataSize())
819 fmt.Fprintf(w, "Metadata have: ")
820 for _, h := range t.metadataCompletedChunks {
821 fmt.Fprintf(w, "%c", func() rune {
831 fmt.Fprintf(w, "Piece length: %s\n",
834 return fmt.Sprintf("%v (%v chunks)",
836 float64(t.usualPieceSize())/float64(t.chunkSize))
843 fmt.Fprintf(w, "Num Pieces: %d (%d completed)\n", t.numPieces(), t.numPiecesCompleted())
844 fmt.Fprintf(w, "Piece States: %s\n", t.pieceStateRuns())
845 // Generates a huge, unhelpful listing when piece availability is very scattered. Prefer
846 // availability frequencies instead.
848 fmt.Fprintf(w, "Piece availability: %v\n", strings.Join(func() (ret []string) {
849 for _, run := range t.pieceAvailabilityRuns() {
850 ret = append(ret, run.String())
855 fmt.Fprintf(w, "Piece availability frequency: %v\n", strings.Join(
856 func() (ret []string) {
857 for avail, freq := range t.pieceAvailabilityFrequencies() {
861 ret = append(ret, fmt.Sprintf("%v: %v", avail, freq))
867 fmt.Fprintf(w, "Reader Pieces:")
868 t.forReaderOffsetPieces(func(begin, end pieceIndex) (again bool) {
869 fmt.Fprintf(w, " %d:%d", begin, end)
874 fmt.Fprintf(w, "Enabled trackers:\n")
876 tw := tabwriter.NewWriter(w, 0, 0, 2, ' ', 0)
877 fmt.Fprintf(tw, " URL\tExtra\n")
878 for _, ta := range slices.Sort(slices.FromMapElems(t.trackerAnnouncers), func(l, r torrentTrackerAnnouncer) bool {
881 var luns, runs url.URL = *lu, *ru
884 var ml missinggo.MultiLess
885 ml.StrictNext(luns.String() == runs.String(), luns.String() < runs.String())
886 ml.StrictNext(lu.String() == ru.String(), lu.String() < ru.String())
888 }).([]torrentTrackerAnnouncer) {
889 fmt.Fprintf(tw, " %q\t%v\n", ta.URL(), ta.statusLine())
894 fmt.Fprintf(w, "DHT Announces: %d\n", t.numDHTAnnounces)
896 dumpStats(w, t.statsLocked())
898 fmt.Fprintf(w, "webseeds:\n")
899 t.writePeerStatuses(w, maps.Values(t.webSeeds))
901 peerConns := maps.Keys(t.conns)
902 // Peers without priorities first, then those with. I'm undecided about how to order peers
903 // without priorities.
904 sort.Slice(peerConns, func(li, ri int) bool {
907 ml := multiless.New()
908 lpp := g.ResultFromTuple(l.peerPriority()).ToOption()
909 rpp := g.ResultFromTuple(r.peerPriority()).ToOption()
910 ml = ml.Bool(lpp.Ok, rpp.Ok)
911 ml = ml.Uint32(rpp.Value, lpp.Value)
915 fmt.Fprintf(w, "%v peer conns:\n", len(peerConns))
916 t.writePeerStatuses(w, g.SliceMap(peerConns, func(pc *PeerConn) *Peer {
921 func (t *Torrent) writePeerStatuses(w io.Writer, peers []*Peer) {
923 for _, c := range peers {
927 w.Write(bytes.TrimRight(
928 bytes.ReplaceAll(buf.Bytes(), []byte("\n"), []byte("\n ")),
933 func (t *Torrent) haveInfo() bool {
937 // Returns a run-time generated MetaInfo that includes the info bytes and
938 // announce-list as currently known to the client.
939 func (t *Torrent) newMetaInfo() metainfo.MetaInfo {
940 return metainfo.MetaInfo{
941 CreationDate: time.Now().Unix(),
942 Comment: "dynamic metainfo from client",
943 CreatedBy: "https://github.com/anacrolix/torrent",
944 AnnounceList: t.metainfo.UpvertedAnnounceList().Clone(),
945 InfoBytes: func() []byte {
947 return t.metadataBytes
952 UrlList: func() []string {
953 ret := make([]string, 0, len(t.webSeeds))
954 for url := range t.webSeeds {
955 ret = append(ret, url)
959 PieceLayers: t.pieceLayers(),
963 // Returns a count of bytes that are not complete in storage, and not pending being written to
964 // storage. This value is from the perspective of the download manager, and may not agree with the
965 // actual state in storage. If you want read data synchronously you should use a Reader. See
966 // https://github.com/anacrolix/torrent/issues/828.
967 func (t *Torrent) BytesMissing() (n int64) {
969 n = t.bytesMissingLocked()
974 func (t *Torrent) bytesMissingLocked() int64 {
978 func iterFlipped(b *roaring.Bitmap, end uint64, cb func(uint32) bool) {
979 roaring.Flip(b, 0, end).Iterate(cb)
982 func (t *Torrent) bytesLeft() (left int64) {
983 iterFlipped(&t._completedPieces, uint64(t.numPieces()), func(x uint32) bool {
984 p := t.piece(pieceIndex(x))
985 left += int64(p.length() - p.numDirtyBytes())
991 // Bytes left to give in tracker announces.
992 func (t *Torrent) bytesLeftAnnounce() int64 {
1000 func (t *Torrent) piecePartiallyDownloaded(piece pieceIndex) bool {
1001 if t.pieceComplete(piece) {
1004 if t.pieceAllDirty(piece) {
1007 return t.pieces[piece].hasDirtyChunks()
1010 func (t *Torrent) usualPieceSize() int {
1011 return int(t.info.PieceLength)
1014 func (t *Torrent) numPieces() pieceIndex {
1015 return t.info.NumPieces()
1018 func (t *Torrent) numPiecesCompleted() (num pieceIndex) {
1019 return pieceIndex(t._completedPieces.GetCardinality())
1022 func (t *Torrent) close(wg *sync.WaitGroup) (err error) {
1023 if !t.closed.Set() {
1024 err = errors.New("already closed")
1027 for _, f := range t.onClose {
1030 if t.storage != nil {
1034 t.storageLock.Lock()
1035 defer t.storageLock.Unlock()
1036 if f := t.storage.Close; f != nil {
1039 t.logger.WithDefaultLevel(log.Warning).Printf("error closing storage: %v", err1)
1044 t.iterPeers(func(p *Peer) {
1047 if t.storage != nil {
1048 t.deletePieceRequestOrder()
1050 t.assertAllPiecesRelativeAvailabilityZero()
1052 t.cl.event.Broadcast()
1053 t.pieceStateChanges.Close()
1054 t.updateWantPeersEvent()
1058 func (t *Torrent) assertAllPiecesRelativeAvailabilityZero() {
1059 for i := range t.pieces {
1061 if p.relativeAvailability != 0 {
1062 panic(fmt.Sprintf("piece %v has relative availability %v", i, p.relativeAvailability))
1067 func (t *Torrent) requestOffset(r Request) int64 {
1068 return torrentRequestOffset(t.length(), int64(t.usualPieceSize()), r)
1071 // Return the request that would include the given offset into the torrent data. Returns !ok if
1072 // there is no such request.
1073 func (t *Torrent) offsetRequest(off int64) (req Request, ok bool) {
1074 return torrentOffsetRequest(t.length(), t.info.PieceLength, int64(t.chunkSize), off)
1077 func (t *Torrent) writeChunk(piece int, begin int64, data []byte) (err error) {
1078 //defer perf.ScopeTimerErr(&err)()
1079 n, err := t.pieces[piece].Storage().WriteAt(data, begin)
1080 if err == nil && n != len(data) {
1081 err = io.ErrShortWrite
1086 func (t *Torrent) bitfield() (bf []bool) {
1087 bf = make([]bool, t.numPieces())
1088 t._completedPieces.Iterate(func(piece uint32) (again bool) {
1095 func (t *Torrent) pieceNumChunks(piece pieceIndex) chunkIndexType {
1096 return chunkIndexType((t.pieceLength(piece) + t.chunkSize - 1) / t.chunkSize)
1099 func (t *Torrent) chunksPerRegularPiece() chunkIndexType {
1100 return t._chunksPerRegularPiece
1103 func (t *Torrent) numChunks() RequestIndex {
1104 if t.numPieces() == 0 {
1107 return RequestIndex(t.numPieces()-1)*t.chunksPerRegularPiece() + t.pieceNumChunks(t.numPieces()-1)
1110 func (t *Torrent) pendAllChunkSpecs(pieceIndex pieceIndex) {
1111 t.dirtyChunks.RemoveRange(
1112 uint64(t.pieceRequestIndexOffset(pieceIndex)),
1113 uint64(t.pieceRequestIndexOffset(pieceIndex+1)))
1116 func (t *Torrent) pieceLength(piece pieceIndex) pp.Integer {
1117 if t.info.PieceLength == 0 {
1118 // There will be no variance amongst pieces. Only pain.
1121 if t.info.FilesArePieceAligned() {
1123 file := p.mustGetOnlyFile()
1124 if piece == file.EndPieceIndex()-1 {
1125 return pp.Integer(file.length - (p.torrentBeginOffset() - file.offset))
1127 return pp.Integer(t.usualPieceSize())
1129 if piece == t.numPieces()-1 {
1130 ret := pp.Integer(t.length() % t.info.PieceLength)
1135 return pp.Integer(t.info.PieceLength)
1138 func (t *Torrent) smartBanBlockCheckingWriter(piece pieceIndex) *blockCheckingWriter {
1139 return &blockCheckingWriter{
1140 cache: &t.smartBanCache,
1141 requestIndex: t.pieceRequestIndexOffset(piece),
1142 chunkSize: t.chunkSize.Int(),
1146 func (t *Torrent) hashPiece(piece pieceIndex) (
1148 // These are peers that sent us blocks that differ from what we hash here.
1149 differingPeers map[bannableAddr]struct{},
1153 p.waitNoPendingWrites()
1154 storagePiece := p.Storage()
1157 // Does the backend want to do its own hashing?
1158 if i, ok := storagePiece.PieceImpl.(storage.SelfHashing); ok {
1159 var sum metainfo.Hash
1160 // log.Printf("A piece decided to self-hash: %d", piece)
1161 sum, err = i.SelfHash()
1162 correct = sum == *p.hash
1163 // Can't do smart banning without reading the piece. The smartBanCache is still cleared
1164 // in pieceHasher regardless.
1167 h := pieceHash.New()
1168 differingPeers, err = t.hashPieceWithSpecificHash(piece, h, t.info.FilesArePieceAligned())
1170 n := len(h.Sum(sum[:0]))
1174 correct = sum == *p.hash
1175 } else if p.hashV2.Ok {
1176 h := merkle.NewHash()
1177 differingPeers, err = t.hashPieceWithSpecificHash(piece, h, false)
1179 n := len(h.Sum(sum[:0]))
1183 correct = sum == p.hashV2.Value
1190 func (t *Torrent) hashPieceWithSpecificHash(piece pieceIndex, h hash.Hash, padV1 bool) (
1191 // These are peers that sent us blocks that differ from what we hash here.
1192 differingPeers map[bannableAddr]struct{},
1196 p.waitNoPendingWrites()
1197 storagePiece := p.Storage()
1199 const logPieceContents = false
1200 smartBanWriter := t.smartBanBlockCheckingWriter(piece)
1201 writers := []io.Writer{h, smartBanWriter}
1202 var examineBuf bytes.Buffer
1203 if logPieceContents {
1204 writers = append(writers, &examineBuf)
1206 multiWriter := io.MultiWriter(writers...)
1209 written, err = storagePiece.WriteTo(multiWriter)
1210 if err == nil && written != int64(p.length()) {
1211 err = fmt.Errorf("wrote %v bytes from storage, piece has length %v", written, p.length())
1212 // Skip smart banning since we can't blame them for storage issues. A short write would
1213 // ban peers for all recorded blocks that weren't just written.
1217 // Flush before writing padding, since we would not have recorded the padding blocks.
1218 smartBanWriter.Flush()
1219 differingPeers = smartBanWriter.badPeers
1220 // For a hybrid torrent, we work with the v2 files, but if we use a v1 hash, we can assume that
1221 // the pieces are padded with zeroes.
1223 paddingLen := p.Info().V1Length() - p.Info().Length()
1224 written, err := io.CopyN(multiWriter, zeroReader, paddingLen)
1225 if written != paddingLen {
1227 "piece %v: wrote %v bytes of padding, expected %v, error: %v",
1235 if logPieceContents {
1236 t.logger.WithNames("hashing").Levelf(log.Debug, "hashed %q with copy err %v", examineBuf.Bytes(), err)
1241 func (t *Torrent) haveAnyPieces() bool {
1242 return !t._completedPieces.IsEmpty()
1245 func (t *Torrent) haveAllPieces() bool {
1249 return t._completedPieces.GetCardinality() == bitmap.BitRange(t.numPieces())
1252 func (t *Torrent) havePiece(index pieceIndex) bool {
1253 return t.haveInfo() && t.pieceComplete(index)
1256 func (t *Torrent) maybeDropMutuallyCompletePeer(
1257 // I'm not sure about taking peer here, not all peer implementations actually drop. Maybe that's
1261 if !t.cl.config.DropMutuallyCompletePeers {
1264 if !t.haveAllPieces() {
1267 if all, known := p.peerHasAllPieces(); !(known && all) {
1273 p.logger.Levelf(log.Debug, "is mutually complete; dropping")
1277 func (t *Torrent) haveChunk(r Request) (ret bool) {
1279 // log.Println("have chunk", r, ret)
1284 if t.pieceComplete(pieceIndex(r.Index)) {
1287 p := &t.pieces[r.Index]
1288 return !p.pendingChunk(r.ChunkSpec, t.chunkSize)
1291 func chunkIndexFromChunkSpec(cs ChunkSpec, chunkSize pp.Integer) chunkIndexType {
1292 return chunkIndexType(cs.Begin / chunkSize)
1295 func (t *Torrent) wantPieceIndex(index pieceIndex) bool {
1296 return !t._pendingPieces.IsEmpty() && t._pendingPieces.Contains(uint32(index))
1299 // A pool of []*PeerConn, to reduce allocations in functions that need to index or sort Torrent
1300 // conns (which is a map).
1301 var peerConnSlices sync.Pool
1303 func getPeerConnSlice(cap int) []*PeerConn {
1304 getInterface := peerConnSlices.Get()
1305 if getInterface == nil {
1306 return make([]*PeerConn, 0, cap)
1308 return getInterface.([]*PeerConn)[:0]
1312 // Calls the given function with a slice of unclosed conns. It uses a pool to reduce allocations as
1313 // this is a frequent occurrence.
1314 func (t *Torrent) withUnclosedConns(f func([]*PeerConn)) {
1315 sl := t.appendUnclosedConns(getPeerConnSlice(len(t.conns)))
1317 peerConnSlices.Put(sl)
1320 func (t *Torrent) worstBadConnFromSlice(opts worseConnLensOpts, sl []*PeerConn) *PeerConn {
1321 wcs := worseConnSlice{conns: sl}
1324 for wcs.Len() != 0 {
1325 c := heap.Pop(&wcs).(*PeerConn)
1326 if opts.incomingIsBad && !c.outgoing {
1329 if opts.outgoingIsBad && c.outgoing {
1332 if c._stats.ChunksReadWasted.Int64() >= 6 && c._stats.ChunksReadWasted.Int64() > c._stats.ChunksReadUseful.Int64() {
1335 // If the connection is in the worst half of the established
1336 // connection quota and is older than a minute.
1337 if wcs.Len() >= (t.maxEstablishedConns+1)/2 {
1338 // Give connections 1 minute to prove themselves.
1339 if time.Since(c.completedHandshake) > time.Minute {
1347 // The worst connection is one that hasn't been sent, or sent anything useful for the longest. A bad
1348 // connection is one that usually sends us unwanted pieces, or has been in the worse half of the
1349 // established connections for more than a minute. This is O(n log n). If there was a way to not
1350 // consider the position of a conn relative to the total number, it could be reduced to O(n).
1351 func (t *Torrent) worstBadConn(opts worseConnLensOpts) (ret *PeerConn) {
1352 t.withUnclosedConns(func(ucs []*PeerConn) {
1353 ret = t.worstBadConnFromSlice(opts, ucs)
1358 type PieceStateChange struct {
1363 func (t *Torrent) publishPieceStateChange(piece pieceIndex) {
1364 t.cl._mu.Defer(func() {
1365 cur := t.pieceState(piece)
1366 p := &t.pieces[piece]
1367 if cur != p.publicPieceState {
1368 p.publicPieceState = cur
1369 t.pieceStateChanges.Publish(PieceStateChange{
1377 func (t *Torrent) pieceNumPendingChunks(piece pieceIndex) pp.Integer {
1378 if t.pieceComplete(piece) {
1381 return pp.Integer(t.pieceNumChunks(piece) - t.pieces[piece].numDirtyChunks())
1384 func (t *Torrent) pieceAllDirty(piece pieceIndex) bool {
1385 return t.pieces[piece].allChunksDirty()
1388 func (t *Torrent) readersChanged() {
1389 t.updateReaderPieces()
1390 t.updateAllPiecePriorities("Torrent.readersChanged")
1393 func (t *Torrent) updateReaderPieces() {
1394 t._readerNowPieces, t._readerReadaheadPieces = t.readerPiecePriorities()
1397 func (t *Torrent) readerPosChanged(from, to pieceRange) {
1401 t.updateReaderPieces()
1402 // Order the ranges, high and low.
1404 if l.begin > h.begin {
1407 if l.end < h.begin {
1408 // Two distinct ranges.
1409 t.updatePiecePriorities(l.begin, l.end, "Torrent.readerPosChanged")
1410 t.updatePiecePriorities(h.begin, h.end, "Torrent.readerPosChanged")
1417 t.updatePiecePriorities(l.begin, end, "Torrent.readerPosChanged")
1421 func (t *Torrent) maybeNewConns() {
1422 // Tickle the accept routine.
1423 t.cl.event.Broadcast()
1427 func (t *Torrent) onPiecePendingTriggers(piece pieceIndex, reason string) {
1428 if t._pendingPieces.Contains(uint32(piece)) {
1429 t.iterPeers(func(c *Peer) {
1430 // if c.requestState.Interested {
1433 if !c.isLowOnRequests() {
1436 if !c.peerHasPiece(piece) {
1439 if c.requestState.Interested && c.peerChoking && !c.peerAllowedFast.Contains(piece) {
1442 c.updateRequests(reason)
1446 t.publishPieceStateChange(piece)
1449 func (t *Torrent) updatePiecePriorityNoTriggers(piece pieceIndex) (pendingChanged bool) {
1450 if !t.closed.IsSet() {
1451 // It would be possible to filter on pure-priority changes here to avoid churning the piece
1453 t.updatePieceRequestOrderPiece(piece)
1456 newPrio := p.effectivePriority()
1457 // t.logger.Printf("torrent %p: piece %d: uncached priority: %v", t, piece, newPrio)
1458 if newPrio == PiecePriorityNone && p.haveHash() {
1459 return t._pendingPieces.CheckedRemove(uint32(piece))
1461 return t._pendingPieces.CheckedAdd(uint32(piece))
1465 func (t *Torrent) updatePiecePriority(piece pieceIndex, reason string) {
1466 if t.updatePiecePriorityNoTriggers(piece) && !t.disableTriggers {
1467 t.onPiecePendingTriggers(piece, reason)
1469 t.updatePieceRequestOrderPiece(piece)
1472 func (t *Torrent) updateAllPiecePriorities(reason string) {
1473 t.updatePiecePriorities(0, t.numPieces(), reason)
1476 // Update all piece priorities in one hit. This function should have the same
1477 // output as updatePiecePriority, but across all pieces.
1478 func (t *Torrent) updatePiecePriorities(begin, end pieceIndex, reason string) {
1479 for i := begin; i < end; i++ {
1480 t.updatePiecePriority(i, reason)
1484 // Returns the range of pieces [begin, end) that contains the extent of bytes.
1485 func (t *Torrent) byteRegionPieces(off, size int64) (begin, end pieceIndex) {
1486 if off >= t.length() {
1496 begin = pieceIndex(off / t.info.PieceLength)
1497 end = pieceIndex((off + size + t.info.PieceLength - 1) / t.info.PieceLength)
1498 if end > pieceIndex(t.info.NumPieces()) {
1499 end = pieceIndex(t.info.NumPieces())
1504 // Returns true if all iterations complete without breaking. Returns the read regions for all
1505 // readers. The reader regions should not be merged as some callers depend on this method to
1506 // enumerate readers.
1507 func (t *Torrent) forReaderOffsetPieces(f func(begin, end pieceIndex) (more bool)) (all bool) {
1508 for r := range t.readers {
1510 if p.begin >= p.end {
1513 if !f(p.begin, p.end) {
1520 func (t *Torrent) pendRequest(req RequestIndex) {
1521 t.piece(t.pieceIndexOfRequestIndex(req)).pendChunkIndex(req % t.chunksPerRegularPiece())
1524 func (t *Torrent) pieceCompletionChanged(piece pieceIndex, reason string) {
1525 t.cl.event.Broadcast()
1526 if t.pieceComplete(piece) {
1527 t.onPieceCompleted(piece)
1529 t.onIncompletePiece(piece)
1531 t.updatePiecePriority(piece, reason)
1534 func (t *Torrent) numReceivedConns() (ret int) {
1535 for c := range t.conns {
1536 if c.Discovery == PeerSourceIncoming {
1543 func (t *Torrent) numOutgoingConns() (ret int) {
1544 for c := range t.conns {
1552 func (t *Torrent) maxHalfOpen() int {
1553 // Note that if we somehow exceed the maximum established conns, we want
1554 // the negative value to have an effect.
1555 establishedHeadroom := int64(t.maxEstablishedConns - len(t.conns))
1556 extraIncoming := int64(t.numReceivedConns() - t.maxEstablishedConns/2)
1557 // We want to allow some experimentation with new peers, and to try to
1558 // upset an oversupply of received connections.
1560 max(5, extraIncoming)+establishedHeadroom,
1561 int64(t.cl.config.HalfOpenConnsPerTorrent),
1565 func (t *Torrent) openNewConns() (initiated int) {
1566 defer t.updateWantPeersEvent()
1567 for t.peers.Len() != 0 {
1568 if !t.wantOutgoingConns() {
1571 if len(t.halfOpen) >= t.maxHalfOpen() {
1574 if len(t.cl.dialers) == 0 {
1577 if t.cl.numHalfOpen >= t.cl.config.TotalHalfOpenConns {
1580 p := t.peers.PopMax()
1581 opts := outgoingConnOpts{
1584 requireRendezvous: false,
1585 skipHolepunchRendezvous: false,
1586 receivedHolepunchConnect: false,
1587 HeaderObfuscationPolicy: t.cl.config.HeaderObfuscationPolicy,
1589 initiateConn(opts, false)
1595 func (t *Torrent) updatePieceCompletion(piece pieceIndex) bool {
1597 uncached := t.pieceCompleteUncached(piece)
1598 cached := p.completion()
1599 changed := cached != uncached
1600 complete := uncached.Complete
1601 p.storageCompletionOk = uncached.Ok
1604 t._completedPieces.Add(x)
1607 t._completedPieces.Remove(x)
1609 p.t.updatePieceRequestOrderPiece(piece)
1611 if complete && len(p.dirtiers) != 0 {
1612 t.logger.Printf("marked piece %v complete but still has dirtiers", piece)
1616 // "piece completion changed",
1617 // slog.Int("piece", piece),
1618 // slog.Any("from", cached),
1619 // slog.Any("to", uncached))
1620 t.pieceCompletionChanged(piece, "Torrent.updatePieceCompletion")
1625 // Non-blocking read. Client lock is not required.
1626 func (t *Torrent) readAt(b []byte, off int64) (n int, err error) {
1628 p := &t.pieces[off/t.info.PieceLength]
1629 p.waitNoPendingWrites()
1631 n1, err = p.Storage().ReadAt(b, off-p.Info().Offset())
1642 // Returns an error if the metadata was completed, but couldn't be set for some reason. Blame it on
1643 // the last peer to contribute. TODO: Actually we shouldn't blame peers for failure to open storage
1644 // etc. Also we should probably cached metadata pieces per-Peer, to isolate failure appropriately.
1645 func (t *Torrent) maybeCompleteMetadata() error {
1650 if !t.haveAllMetadataPieces() {
1651 // Don't have enough metadata pieces.
1654 err := t.setInfoBytesLocked(t.metadataBytes)
1656 t.invalidateMetadata()
1657 return fmt.Errorf("error setting info bytes: %s", err)
1659 if t.cl.config.Debug {
1660 t.logger.Printf("%s: got metadata from peers", t)
1665 func (t *Torrent) readerPiecePriorities() (now, readahead bitmap.Bitmap) {
1666 t.forReaderOffsetPieces(func(begin, end pieceIndex) bool {
1668 now.Add(bitmap.BitIndex(begin))
1669 readahead.AddRange(bitmap.BitRange(begin)+1, bitmap.BitRange(end))
1676 func (t *Torrent) needData() bool {
1677 if t.closed.IsSet() {
1683 return !t._pendingPieces.IsEmpty()
1686 func appendMissingStrings(old, new []string) (ret []string) {
1689 for _, n := range new {
1690 for _, o := range old {
1695 ret = append(ret, n)
1700 func appendMissingTrackerTiers(existing [][]string, minNumTiers int) (ret [][]string) {
1702 for minNumTiers > len(ret) {
1703 ret = append(ret, nil)
1708 func (t *Torrent) addTrackers(announceList [][]string) {
1709 fullAnnounceList := &t.metainfo.AnnounceList
1710 t.metainfo.AnnounceList = appendMissingTrackerTiers(*fullAnnounceList, len(announceList))
1711 for tierIndex, trackerURLs := range announceList {
1712 (*fullAnnounceList)[tierIndex] = appendMissingStrings((*fullAnnounceList)[tierIndex], trackerURLs)
1714 t.startMissingTrackerScrapers()
1715 t.updateWantPeersEvent()
1718 // Don't call this before the info is available.
1719 func (t *Torrent) bytesCompleted() int64 {
1723 return t.length() - t.bytesLeft()
1726 func (t *Torrent) SetInfoBytes(b []byte) (err error) {
1729 return t.setInfoBytesLocked(b)
1732 // Returns true if connection is removed from torrent.Conns.
1733 func (t *Torrent) deletePeerConn(c *PeerConn) (ret bool) {
1734 if !c.closed.IsSet() {
1735 panic("connection is not closed")
1736 // There are behaviours prevented by the closed state that will fail
1737 // if the connection has been deleted.
1741 // Avoid adding a drop event more than once. Probably we should track whether we've generated
1742 // the drop event against the PexConnState instead.
1744 if !t.cl.config.DisablePEX {
1748 torrent.Add("deleted connections", 1)
1749 c.deleteAllRequests("Torrent.deletePeerConn")
1750 t.assertPendingRequests()
1751 if t.numActivePeers() == 0 && len(t.connsWithAllPieces) != 0 {
1752 panic(t.connsWithAllPieces)
1757 func (t *Torrent) decPeerPieceAvailability(p *Peer) {
1758 if t.deleteConnWithAllPieces(p) {
1764 p.peerPieces().Iterate(func(i uint32) bool {
1765 p.t.decPieceAvailability(pieceIndex(i))
1770 func (t *Torrent) assertPendingRequests() {
1774 // var actual pendingRequests
1775 // if t.haveInfo() {
1776 // actual.m = make([]int, t.numChunks())
1778 // t.iterPeers(func(p *Peer) {
1779 // p.requestState.Requests.Iterate(func(x uint32) bool {
1784 // diff := cmp.Diff(actual.m, t.pendingRequests.m)
1790 func (t *Torrent) dropConnection(c *PeerConn) {
1791 t.cl.event.Broadcast()
1793 if t.deletePeerConn(c) {
1798 // Peers as in contact information for dialing out.
1799 func (t *Torrent) wantPeers() bool {
1800 if t.closed.IsSet() {
1803 if t.peers.Len() > t.cl.config.TorrentPeersLowWater {
1806 return t.wantOutgoingConns()
1809 func (t *Torrent) updateWantPeersEvent() {
1811 t.wantPeersEvent.Set()
1813 t.wantPeersEvent.Clear()
1817 // Returns whether the client should make effort to seed the torrent.
1818 func (t *Torrent) seeding() bool {
1820 if t.closed.IsSet() {
1823 if t.dataUploadDisallowed {
1826 if cl.config.NoUpload {
1829 if !cl.config.Seed {
1832 if cl.config.DisableAggressiveUpload && t.needData() {
1838 func (t *Torrent) onWebRtcConn(
1839 c datachannel.ReadWriteCloser,
1840 dcc webtorrent.DataChannelContext,
1843 netConn := webrtcNetConn{
1845 DataChannelContext: dcc,
1847 peerRemoteAddr := netConn.RemoteAddr()
1848 //t.logger.Levelf(log.Critical, "onWebRtcConn remote addr: %v", peerRemoteAddr)
1849 if t.cl.badPeerAddr(peerRemoteAddr) {
1852 localAddrIpPort := missinggo.IpPortFromNetAddr(netConn.LocalAddr())
1853 pc, err := t.cl.initiateProtocolHandshakes(
1854 context.Background(),
1859 outgoing: dcc.LocalOffered,
1860 remoteAddr: peerRemoteAddr,
1861 localPublicAddr: localAddrIpPort,
1862 network: webrtcNetwork,
1863 connString: fmt.Sprintf("webrtc offer_id %x: %v", dcc.OfferId, regularNetConnPeerConnConnString(netConn)),
1867 t.logger.WithDefaultLevel(log.Error).Printf("error in handshaking webrtc connection: %v", err)
1870 if dcc.LocalOffered {
1871 pc.Discovery = PeerSourceTracker
1873 pc.Discovery = PeerSourceIncoming
1875 pc.conn.SetWriteDeadline(time.Time{})
1878 err = t.runHandshookConn(pc)
1880 t.logger.WithDefaultLevel(log.Debug).Printf("error running handshook webrtc conn: %v", err)
1884 func (t *Torrent) logRunHandshookConn(pc *PeerConn, logAll bool, level log.Level) {
1885 err := t.runHandshookConn(pc)
1886 if err != nil || logAll {
1887 t.logger.WithDefaultLevel(level).Levelf(log.ErrorLevel(err), "error running handshook conn: %v", err)
1891 func (t *Torrent) runHandshookConnLoggingErr(pc *PeerConn) {
1892 t.logRunHandshookConn(pc, false, log.Debug)
1895 func (t *Torrent) startWebsocketAnnouncer(u url.URL, shortInfohash [20]byte) torrentTrackerAnnouncer {
1896 wtc, release := t.cl.websocketTrackers.Get(u.String(), shortInfohash)
1897 // This needs to run before the Torrent is dropped from the Client, to prevent a new
1898 // webtorrent.TrackerClient for the same info hash before the old one is cleaned up.
1899 t.onClose = append(t.onClose, release)
1900 wst := websocketTrackerStatus{u, wtc}
1902 err := wtc.Announce(tracker.Started, shortInfohash)
1904 t.logger.WithDefaultLevel(log.Warning).Printf(
1905 "error in initial announce to %q: %v",
1913 func (t *Torrent) startScrapingTracker(_url string) {
1917 u, err := url.Parse(_url)
1919 // URLs with a leading '*' appear to be a uTorrent convention to disable trackers.
1921 t.logger.Levelf(log.Warning, "error parsing tracker url: %v", err)
1925 if u.Scheme == "udp" {
1927 t.startScrapingTracker(u.String())
1929 t.startScrapingTracker(u.String())
1933 t.startScrapingTrackerWithInfohash(u, _url, t.infoHash.Value)
1935 if t.infoHashV2.Ok {
1936 t.startScrapingTrackerWithInfohash(u, _url, *t.infoHashV2.Value.ToShort())
1940 func (t *Torrent) startScrapingTrackerWithInfohash(u *url.URL, urlStr string, shortInfohash [20]byte) {
1941 announcerKey := torrentTrackerAnnouncerKey{
1942 shortInfohash: shortInfohash,
1945 if _, ok := t.trackerAnnouncers[announcerKey]; ok {
1948 sl := func() torrentTrackerAnnouncer {
1951 if t.cl.config.DisableWebtorrent {
1954 return t.startWebsocketAnnouncer(*u, shortInfohash)
1956 if t.cl.config.DisableIPv4Peers || t.cl.config.DisableIPv4 {
1960 if t.cl.config.DisableIPv6 {
1964 newAnnouncer := &trackerScraper{
1965 shortInfohash: shortInfohash,
1968 lookupTrackerIp: t.cl.config.LookupTrackerIp,
1970 go newAnnouncer.Run()
1976 g.MakeMapIfNil(&t.trackerAnnouncers)
1977 if g.MapInsert(t.trackerAnnouncers, announcerKey, sl).Ok {
1978 panic("tracker announcer already exists")
1982 // Adds and starts tracker scrapers for tracker URLs that aren't already
1984 func (t *Torrent) startMissingTrackerScrapers() {
1985 if t.cl.config.DisableTrackers {
1988 t.startScrapingTracker(t.metainfo.Announce)
1989 for _, tier := range t.metainfo.AnnounceList {
1990 for _, url := range tier {
1991 t.startScrapingTracker(url)
1996 // Returns an AnnounceRequest with fields filled out to defaults and current
1998 func (t *Torrent) announceRequest(
1999 event tracker.AnnounceEvent,
2000 shortInfohash [20]byte,
2001 ) tracker.AnnounceRequest {
2002 // Note that IPAddress is not set. It's set for UDP inside the tracker code, since it's
2003 // dependent on the network in use.
2004 return tracker.AnnounceRequest{
2006 NumWant: func() int32 {
2007 if t.wantPeers() && len(t.cl.dialers) > 0 {
2008 // Windozer has UDP packet limit. See:
2009 // https://github.com/anacrolix/torrent/issues/764
2015 Port: uint16(t.cl.incomingPeerPort()),
2016 PeerId: t.cl.peerID,
2017 InfoHash: shortInfohash,
2018 Key: t.cl.announceKey(),
2020 // The following are vaguely described in BEP 3.
2022 Left: t.bytesLeftAnnounce(),
2023 Uploaded: t.stats.BytesWrittenData.Int64(),
2024 // There's no mention of wasted or unwanted download in the BEP.
2025 Downloaded: t.stats.BytesReadUsefulData.Int64(),
2029 // Adds peers revealed in an announce until the announce ends, or we have
2031 func (t *Torrent) consumeDhtAnnouncePeers(pvs <-chan dht.PeersValues) {
2033 for v := range pvs {
2036 for _, cp := range v.Peers {
2038 // Can't do anything with this.
2041 if t.addPeer(PeerInfo{
2042 Addr: ipPortAddr{cp.IP, cp.Port},
2043 Source: PeerSourceDhtGetPeers,
2050 // log.Printf("added %v peers from dht for %v", added, t.InfoHash().HexString())
2055 // Announce using the provided DHT server. Peers are consumed automatically. done is closed when the
2056 // announce ends. stop will force the announce to end. This interface is really old-school, and
2057 // calls a private one that is much more modern. Both v1 and v2 info hashes are announced if they
2059 func (t *Torrent) AnnounceToDht(s DhtServer) (done <-chan struct{}, stop func(), err error) {
2062 t.eachShortInfohash(func(short [20]byte) {
2063 ihs = append(ihs, short)
2066 ctx, stop := context.WithCancel(context.Background())
2067 eg, ctx := errgroup.WithContext(ctx)
2068 for _, ih := range ihs {
2070 ann, err = s.Announce(ih, t.cl.incomingPeerPort(), true)
2075 eg.Go(func() error {
2076 return t.dhtAnnounceConsumer(ctx, ann)
2079 _done := make(chan struct{})
2089 // Announce using the provided DHT server. Peers are consumed automatically. done is closed when the
2090 // announce ends. stop will force the announce to end.
2091 func (t *Torrent) dhtAnnounceConsumer(
2092 ctx context.Context,
2098 done := make(chan struct{})
2101 t.consumeDhtAnnouncePeers(ps.Peers())
2105 return context.Cause(ctx)
2111 func (t *Torrent) timeboxedAnnounceToDht(s DhtServer) error {
2112 _, stop, err := t.AnnounceToDht(s)
2117 case <-t.closed.Done():
2118 case <-time.After(5 * time.Minute):
2124 func (t *Torrent) dhtAnnouncer(s DhtServer) {
2130 if t.closed.IsSet() {
2133 // We're also announcing ourselves as a listener, so we don't just want peer addresses.
2134 // TODO: We can include the announce_peer step depending on whether we can receive
2135 // inbound connections. We should probably only announce once every 15 mins too.
2136 if !t.wantAnyConns() {
2139 // TODO: Determine if there's a listener on the port we're announcing.
2140 if len(cl.dialers) == 0 && len(cl.listeners) == 0 {
2151 err := t.timeboxedAnnounceToDht(s)
2153 t.logger.WithDefaultLevel(log.Warning).Printf("error announcing %q to DHT: %s", t, err)
2159 func (t *Torrent) addPeers(peers []PeerInfo) (added int) {
2160 for _, p := range peers {
2168 // The returned TorrentStats may require alignment in memory. See
2169 // https://github.com/anacrolix/torrent/issues/383.
2170 func (t *Torrent) Stats() TorrentStats {
2172 defer t.cl.rUnlock()
2173 return t.statsLocked()
2176 func (t *Torrent) statsLocked() (ret TorrentStats) {
2177 ret.ActivePeers = len(t.conns)
2178 ret.HalfOpenPeers = len(t.halfOpen)
2179 ret.PendingPeers = t.peers.Len()
2180 ret.TotalPeers = t.numTotalPeers()
2181 ret.ConnectedSeeders = 0
2182 for c := range t.conns {
2183 if all, ok := c.peerHasAllPieces(); all && ok {
2184 ret.ConnectedSeeders++
2187 ret.ConnStats = t.stats.Copy()
2188 ret.PiecesComplete = t.numPiecesCompleted()
2192 // The total number of peers in the torrent.
2193 func (t *Torrent) numTotalPeers() int {
2194 peers := make(map[string]struct{})
2195 for conn := range t.conns {
2196 ra := conn.conn.RemoteAddr()
2198 // It's been closed and doesn't support RemoteAddr.
2201 peers[ra.String()] = struct{}{}
2203 for addr := range t.halfOpen {
2204 peers[addr] = struct{}{}
2206 t.peers.Each(func(peer PeerInfo) {
2207 peers[peer.Addr.String()] = struct{}{}
2212 // Reconcile bytes transferred before connection was associated with a
2214 func (t *Torrent) reconcileHandshakeStats(c *Peer) {
2215 if c._stats != (ConnStats{
2216 // Handshakes should only increment these fields:
2217 BytesWritten: c._stats.BytesWritten,
2218 BytesRead: c._stats.BytesRead,
2222 c.postHandshakeStats(func(cs *ConnStats) {
2223 cs.BytesRead.Add(c._stats.BytesRead.Int64())
2224 cs.BytesWritten.Add(c._stats.BytesWritten.Int64())
2226 c.reconciledHandshakeStats = true
2229 // Returns true if the connection is added.
2230 func (t *Torrent) addPeerConn(c *PeerConn) (err error) {
2233 torrent.Add("added connections", 1)
2236 if t.closed.IsSet() {
2237 return errors.New("torrent closed")
2239 for c0 := range t.conns {
2240 if c.PeerID != c0.PeerID {
2243 if !t.cl.config.DropDuplicatePeerIds {
2246 if c.hasPreferredNetworkOver(c0) {
2248 t.deletePeerConn(c0)
2250 return errors.New("existing connection preferred")
2253 if len(t.conns) >= t.maxEstablishedConns {
2254 numOutgoing := t.numOutgoingConns()
2255 numIncoming := len(t.conns) - numOutgoing
2256 c := t.worstBadConn(worseConnLensOpts{
2257 // We've already established that we have too many connections at this point, so we just
2258 // need to match what kind we have too many of vs. what we're trying to add now.
2259 incomingIsBad: (numIncoming-numOutgoing > 1) && c.outgoing,
2260 outgoingIsBad: (numOutgoing-numIncoming > 1) && !c.outgoing,
2263 return errors.New("don't want conn")
2268 if len(t.conns) >= t.maxEstablishedConns {
2271 t.conns[c] = struct{}{}
2272 t.cl.event.Broadcast()
2273 // We'll never receive the "p" extended handshake parameter.
2274 if !t.cl.config.DisablePEX && !c.PeerExtensionBytes.SupportsExtended() {
2280 func (t *Torrent) newConnsAllowed() bool {
2281 if !t.networkingEnabled.Bool() {
2284 if t.closed.IsSet() {
2287 if !t.needData() && (!t.seeding() || !t.haveAnyPieces()) {
2293 func (t *Torrent) wantAnyConns() bool {
2294 if !t.networkingEnabled.Bool() {
2297 if t.closed.IsSet() {
2300 if !t.needData() && (!t.seeding() || !t.haveAnyPieces()) {
2303 return len(t.conns) < t.maxEstablishedConns
2306 func (t *Torrent) wantOutgoingConns() bool {
2307 if !t.newConnsAllowed() {
2310 if len(t.conns) < t.maxEstablishedConns {
2313 numIncomingConns := len(t.conns) - t.numOutgoingConns()
2314 return t.worstBadConn(worseConnLensOpts{
2315 incomingIsBad: numIncomingConns-t.numOutgoingConns() > 1,
2316 outgoingIsBad: false,
2320 func (t *Torrent) wantIncomingConns() bool {
2321 if !t.newConnsAllowed() {
2324 if len(t.conns) < t.maxEstablishedConns {
2327 numIncomingConns := len(t.conns) - t.numOutgoingConns()
2328 return t.worstBadConn(worseConnLensOpts{
2329 incomingIsBad: false,
2330 outgoingIsBad: t.numOutgoingConns()-numIncomingConns > 1,
2334 func (t *Torrent) SetMaxEstablishedConns(max int) (oldMax int) {
2337 oldMax = t.maxEstablishedConns
2338 t.maxEstablishedConns = max
2339 wcs := worseConnSlice{
2340 conns: t.appendConns(nil, func(*PeerConn) bool {
2344 wcs.initKeys(worseConnLensOpts{})
2346 for len(t.conns) > t.maxEstablishedConns && wcs.Len() > 0 {
2347 t.dropConnection(heap.Pop(&wcs).(*PeerConn))
2353 func (t *Torrent) pieceHashed(piece pieceIndex, passed bool, hashIoErr error) {
2354 t.logger.LazyLog(log.Debug, func() log.Msg {
2355 return log.Fstr("hashed piece %d (passed=%t)", piece, passed)
2359 t.cl.event.Broadcast()
2360 if t.closed.IsSet() {
2364 // Don't score the first time a piece is hashed, it could be an initial check.
2365 if p.storageCompletionOk {
2367 pieceHashedCorrect.Add(1)
2370 "piece %d failed hash: %d connections contributed", piece, len(p.dirtiers),
2371 ).AddValues(t, p).LogLevel(log.Info, t.logger)
2372 pieceHashedNotCorrect.Add(1)
2377 t.publishPieceStateChange(piece)
2380 t.publishPieceStateChange(piece)
2384 if len(p.dirtiers) != 0 {
2385 // Don't increment stats above connection-level for every involved connection.
2386 t.allStats((*ConnStats).incrementPiecesDirtiedGood)
2388 for c := range p.dirtiers {
2389 c._stats.incrementPiecesDirtiedGood()
2391 t.clearPieceTouchers(piece)
2392 hasDirty := p.hasDirtyChunks()
2395 p.Flush() // You can be synchronous here!
2397 err := p.Storage().MarkComplete()
2399 t.logger.Levelf(log.Warning, "%T: error marking piece complete %d: %s", t.storage, piece, err)
2403 if t.closed.IsSet() {
2406 t.pendAllChunkSpecs(piece)
2408 if len(p.dirtiers) != 0 && p.allChunksDirty() && hashIoErr == nil {
2409 // Peers contributed to all the data for this piece hash failure, and the failure was
2410 // not due to errors in the storage (such as data being dropped in a cache).
2412 // Increment Torrent and above stats, and then specific connections.
2413 t.allStats((*ConnStats).incrementPiecesDirtiedBad)
2414 for c := range p.dirtiers {
2415 // Y u do dis peer?!
2416 c.stats().incrementPiecesDirtiedBad()
2419 bannableTouchers := make([]*Peer, 0, len(p.dirtiers))
2420 for c := range p.dirtiers {
2422 bannableTouchers = append(bannableTouchers, c)
2425 t.clearPieceTouchers(piece)
2426 slices.Sort(bannableTouchers, connLessTrusted)
2428 if t.cl.config.Debug {
2430 "bannable conns by trust for piece %d: %v",
2432 func() (ret []connectionTrust) {
2433 for _, c := range bannableTouchers {
2434 ret = append(ret, c.trust())
2441 if len(bannableTouchers) >= 1 {
2442 c := bannableTouchers[0]
2443 if len(bannableTouchers) != 1 {
2444 t.logger.Levelf(log.Debug, "would have banned %v for touching piece %v after failed piece check", c.remoteIp(), piece)
2446 // Turns out it's still useful to ban peers like this because if there's only a
2447 // single peer for a piece, and we never progress that piece to completion, we
2448 // will never smart-ban them. Discovered in
2449 // https://github.com/anacrolix/torrent/issues/715.
2452 "banning %v for being sole dirtier of piece %v after failed piece check",
2460 t.onIncompletePiece(piece)
2461 p.Storage().MarkNotComplete()
2463 t.updatePieceCompletion(piece)
2466 func (t *Torrent) cancelRequestsForPiece(piece pieceIndex) {
2467 start := t.pieceRequestIndexOffset(piece)
2468 end := start + t.pieceNumChunks(piece)
2469 for ri := start; ri < end; ri++ {
2474 func (t *Torrent) onPieceCompleted(piece pieceIndex) {
2475 t.pendAllChunkSpecs(piece)
2476 t.cancelRequestsForPiece(piece)
2477 t.piece(piece).readerCond.Broadcast()
2478 for conn := range t.conns {
2480 t.maybeDropMutuallyCompletePeer(conn)
2484 // Called when a piece is found to be not complete.
2485 func (t *Torrent) onIncompletePiece(piece pieceIndex) {
2486 if t.pieceAllDirty(piece) {
2487 t.pendAllChunkSpecs(piece)
2489 if !t.wantPieceIndex(piece) {
2490 // t.logger.Printf("piece %d incomplete and unwanted", piece)
2493 // We could drop any connections that we told we have a piece that we
2494 // don't here. But there's a test failure, and it seems clients don't care
2495 // if you request pieces that you already claim to have. Pruning bad
2496 // connections might just remove any connections that aren't treating us
2497 // favourably anyway.
2499 // for c := range t.conns {
2500 // if c.sentHave(piece) {
2504 t.iterPeers(func(conn *Peer) {
2505 if conn.peerHasPiece(piece) {
2506 conn.updateRequests("piece incomplete")
2511 func (t *Torrent) tryCreateMorePieceHashers() {
2512 for !t.closed.IsSet() && t.activePieceHashes < t.cl.config.PieceHashersPerTorrent && t.tryCreatePieceHasher() {
2516 func (t *Torrent) tryCreatePieceHasher() bool {
2517 if t.storage == nil {
2520 pi, ok := t.getPieceToHash()
2525 t.piecesQueuedForHash.Remove(bitmap.BitIndex(pi))
2527 t.publishPieceStateChange(pi)
2528 t.updatePiecePriority(pi, "Torrent.tryCreatePieceHasher")
2529 t.storageLock.RLock()
2530 t.activePieceHashes++
2531 go t.pieceHasher(pi)
2535 func (t *Torrent) getPieceToHash() (ret pieceIndex, ok bool) {
2536 t.piecesQueuedForHash.IterTyped(func(i pieceIndex) bool {
2537 if t.piece(i).hashing {
2547 func (t *Torrent) dropBannedPeers() {
2548 t.iterPeers(func(p *Peer) {
2549 remoteIp := p.remoteIp()
2550 if remoteIp == nil {
2551 if p.bannableAddr.Ok {
2552 t.logger.WithDefaultLevel(log.Debug).Printf("can't get remote ip for peer %v", p)
2556 netipAddr := netip.MustParseAddr(remoteIp.String())
2557 if Some(netipAddr) != p.bannableAddr {
2558 t.logger.WithDefaultLevel(log.Debug).Printf(
2559 "peer remote ip does not match its bannable addr [peer=%v, remote ip=%v, bannable addr=%v]",
2560 p, remoteIp, p.bannableAddr)
2562 if _, ok := t.cl.badPeerIPs[netipAddr]; ok {
2563 // Should this be a close?
2565 t.logger.WithDefaultLevel(log.Debug).Printf("dropped %v for banned remote IP %v", p, netipAddr)
2570 func (t *Torrent) pieceHasher(index pieceIndex) {
2572 // Do we really need to spell out that it's a copy error? If it's a failure to hash the hash
2573 // will just be wrong.
2574 correct, failedPeers, copyErr := t.hashPiece(index)
2578 t.logger.WithNames("hashing").Levelf(
2580 "error hashing piece %v: %v", index, copyErr)
2582 t.storageLock.RUnlock()
2586 for peer := range failedPeers {
2587 t.cl.banPeerIP(peer.AsSlice())
2588 t.logger.WithDefaultLevel(log.Debug).Printf("smart banned %v for piece %v", peer, index)
2591 for ri := t.pieceRequestIndexOffset(index); ri < t.pieceRequestIndexOffset(index+1); ri++ {
2592 t.smartBanCache.ForgetBlock(ri)
2596 t.pieceHashed(index, correct, copyErr)
2597 t.updatePiecePriority(index, "Torrent.pieceHasher")
2598 t.activePieceHashes--
2599 t.tryCreateMorePieceHashers()
2602 // Return the connections that touched a piece, and clear the entries while doing it.
2603 func (t *Torrent) clearPieceTouchers(pi pieceIndex) {
2605 for c := range p.dirtiers {
2606 delete(c.peerTouchedPieces, pi)
2607 delete(p.dirtiers, c)
2611 func (t *Torrent) peersAsSlice() (ret []*Peer) {
2612 t.iterPeers(func(p *Peer) {
2613 ret = append(ret, p)
2618 func (t *Torrent) queueInitialPieceCheck(i pieceIndex) {
2619 if !t.initialPieceCheckDisabled && !t.piece(i).storageCompletionOk {
2620 t.queuePieceCheck(i)
2624 func (t *Torrent) queuePieceCheck(pieceIndex pieceIndex) {
2625 piece := t.piece(pieceIndex)
2626 if piece.hash == nil && !piece.hashV2.Ok {
2629 if piece.queuedForHash() {
2632 t.piecesQueuedForHash.Add(bitmap.BitIndex(pieceIndex))
2633 t.publishPieceStateChange(pieceIndex)
2634 t.updatePiecePriority(pieceIndex, "Torrent.queuePieceCheck")
2635 t.tryCreateMorePieceHashers()
2638 // Forces all the pieces to be re-hashed. See also Piece.VerifyData. This should not be called
2639 // before the Info is available.
2640 func (t *Torrent) VerifyData() {
2641 for i := pieceIndex(0); i < t.NumPieces(); i++ {
2642 t.Piece(i).VerifyData()
2646 func (t *Torrent) connectingToPeerAddr(addrStr string) bool {
2647 return len(t.halfOpen[addrStr]) != 0
2650 func (t *Torrent) hasPeerConnForAddr(x PeerRemoteAddr) bool {
2651 addrStr := x.String()
2652 for c := range t.conns {
2654 if ra.String() == addrStr {
2661 func (t *Torrent) getHalfOpenPath(
2663 attemptKey outgoingConnAttemptKey,
2664 ) nestedmaps.Path[*PeerInfo] {
2665 return nestedmaps.Next(nestedmaps.Next(nestedmaps.Begin(&t.halfOpen), addrStr), attemptKey)
2668 func (t *Torrent) addHalfOpen(addrStr string, attemptKey *PeerInfo) {
2669 path := t.getHalfOpenPath(addrStr, attemptKey)
2671 panic("should be unique")
2673 path.Set(attemptKey)
2677 // Start the process of connecting to the given peer for the given torrent if appropriate. I'm not
2678 // sure all the PeerInfo fields are being used.
2680 opts outgoingConnOpts,
2684 peer := opts.peerInfo
2685 if peer.Id == t.cl.peerID {
2688 if t.cl.badPeerAddr(peer.Addr) && !peer.Trusted {
2692 addrStr := addr.String()
2694 if t.connectingToPeerAddr(addrStr) {
2698 if t.hasPeerConnForAddr(addr) {
2702 t.addHalfOpen(addrStr, attemptKey)
2703 go t.cl.outgoingConnection(
2709 // Adds a trusted, pending peer for each of the given Client's addresses. Typically used in tests to
2710 // quickly make one Client visible to the Torrent of another Client.
2711 func (t *Torrent) AddClientPeer(cl *Client) int {
2712 return t.AddPeers(func() (ps []PeerInfo) {
2713 for _, la := range cl.ListenAddrs() {
2714 ps = append(ps, PeerInfo{
2723 // All stats that include this Torrent. Useful when we want to increment ConnStats but not for every
2725 func (t *Torrent) allStats(f func(*ConnStats)) {
2730 func (t *Torrent) hashingPiece(i pieceIndex) bool {
2731 return t.pieces[i].hashing
2734 func (t *Torrent) pieceQueuedForHash(i pieceIndex) bool {
2735 return t.piecesQueuedForHash.Get(bitmap.BitIndex(i))
2738 func (t *Torrent) dialTimeout() time.Duration {
2739 return reducedDialTimeout(t.cl.config.MinDialTimeout, t.cl.config.NominalDialTimeout, t.cl.config.HalfOpenConnsPerTorrent, t.peers.Len())
2742 func (t *Torrent) piece(i int) *Piece {
2746 func (t *Torrent) onWriteChunkErr(err error) {
2747 if t.userOnWriteChunkErr != nil {
2748 go t.userOnWriteChunkErr(err)
2751 t.logger.WithDefaultLevel(log.Critical).Printf("default chunk write error handler: disabling data download")
2752 t.disallowDataDownloadLocked()
2755 func (t *Torrent) DisallowDataDownload() {
2758 t.disallowDataDownloadLocked()
2761 func (t *Torrent) disallowDataDownloadLocked() {
2762 t.dataDownloadDisallowed.Set()
2763 t.iterPeers(func(p *Peer) {
2764 // Could check if peer request state is empty/not interested?
2765 p.updateRequests("disallow data download")
2766 p.cancelAllRequests()
2770 func (t *Torrent) AllowDataDownload() {
2773 t.dataDownloadDisallowed.Clear()
2774 t.iterPeers(func(p *Peer) {
2775 p.updateRequests("allow data download")
2779 // Enables uploading data, if it was disabled.
2780 func (t *Torrent) AllowDataUpload() {
2783 t.dataUploadDisallowed = false
2784 t.iterPeers(func(p *Peer) {
2785 p.updateRequests("allow data upload")
2789 // Disables uploading data, if it was enabled.
2790 func (t *Torrent) DisallowDataUpload() {
2793 t.dataUploadDisallowed = true
2794 for c := range t.conns {
2795 // TODO: This doesn't look right. Shouldn't we tickle writers to choke peers or something instead?
2796 c.updateRequests("disallow data upload")
2800 // Sets a handler that is called if there's an error writing a chunk to local storage. By default,
2801 // or if nil, a critical message is logged, and data download is disabled.
2802 func (t *Torrent) SetOnWriteChunkError(f func(error)) {
2805 t.userOnWriteChunkErr = f
2808 func (t *Torrent) iterPeers(f func(p *Peer)) {
2809 for pc := range t.conns {
2812 for _, ws := range t.webSeeds {
2817 func (t *Torrent) callbacks() *Callbacks {
2818 return &t.cl.config.Callbacks
2821 type AddWebSeedsOpt func(*webseed.Client)
2823 // Sets the WebSeed trailing path escaper for a webseed.Client.
2824 func WebSeedPathEscaper(custom webseed.PathEscaper) AddWebSeedsOpt {
2825 return func(c *webseed.Client) {
2826 c.PathEscaper = custom
2830 func (t *Torrent) AddWebSeeds(urls []string, opts ...AddWebSeedsOpt) {
2833 for _, u := range urls {
2834 t.addWebSeed(u, opts...)
2838 func (t *Torrent) addWebSeed(url string, opts ...AddWebSeedsOpt) {
2839 if t.cl.config.DisableWebseeds {
2842 if _, ok := t.webSeeds[url]; ok {
2845 // I don't think Go http supports pipelining requests. However, we can have more ready to go
2846 // right away. This value should be some multiple of the number of connections to a host. I
2847 // would expect that double maxRequests plus a bit would be appropriate. This value is based on
2848 // downloading Sintel (08ada5a7a6183aae1e09d831df6748d566095a10) from
2849 // "https://webtorrent.io/torrents/".
2850 const maxRequests = 16
2856 reconciledHandshakeStats: true,
2857 // This should affect how often we have to recompute requests for this peer. Note that
2858 // because we can request more than 1 thing at a time over HTTP, we will hit the low
2859 // requests mark more often, so recomputation is probably sooner than with regular peer
2860 // conns. ~4x maxRequests would be about right.
2861 PeerMaxRequests: 128,
2862 // TODO: Set ban prefix?
2863 RemoteAddr: remoteAddrFromUrl(url),
2864 callbacks: t.callbacks(),
2866 client: webseed.Client{
2867 HttpClient: t.cl.httpClient,
2869 ResponseBodyWrapper: func(r io.Reader) io.Reader {
2870 return &rateLimitedReader{
2871 l: t.cl.config.DownloadRateLimiter,
2876 activeRequests: make(map[Request]webseed.Request, maxRequests),
2878 ws.peer.initRequestState()
2879 for _, opt := range opts {
2882 ws.peer.initUpdateRequestsTimer()
2883 ws.requesterCond.L = t.cl.locker()
2884 for i := 0; i < maxRequests; i += 1 {
2887 for _, f := range t.callbacks().NewPeer {
2890 ws.peer.logger = t.logger.WithContextValue(&ws)
2891 ws.peer.peerImpl = &ws
2893 ws.onGotInfo(t.info)
2895 t.webSeeds[url] = &ws.peer
2898 func (t *Torrent) peerIsActive(p *Peer) (active bool) {
2899 t.iterPeers(func(p1 *Peer) {
2907 func (t *Torrent) requestIndexToRequest(ri RequestIndex) Request {
2908 index := t.pieceIndexOfRequestIndex(ri)
2911 t.piece(index).chunkIndexSpec(ri % t.chunksPerRegularPiece()),
2915 func (t *Torrent) requestIndexFromRequest(r Request) RequestIndex {
2916 return t.pieceRequestIndexOffset(pieceIndex(r.Index)) + RequestIndex(r.Begin/t.chunkSize)
2919 func (t *Torrent) pieceRequestIndexOffset(piece pieceIndex) RequestIndex {
2920 return RequestIndex(piece) * t.chunksPerRegularPiece()
2923 func (t *Torrent) updateComplete() {
2924 t.Complete.SetBool(t.haveAllPieces())
2927 func (t *Torrent) cancelRequest(r RequestIndex) *Peer {
2928 p := t.requestingPeer(r)
2932 // TODO: This is a check that an old invariant holds. It can be removed after some testing.
2933 //delete(t.pendingRequests, r)
2934 if _, ok := t.requestState[r]; ok {
2935 panic("expected request state to be gone")
2940 func (t *Torrent) requestingPeer(r RequestIndex) *Peer {
2941 return t.requestState[r].peer
2944 func (t *Torrent) addConnWithAllPieces(p *Peer) {
2945 if t.connsWithAllPieces == nil {
2946 t.connsWithAllPieces = make(map[*Peer]struct{}, t.maxEstablishedConns)
2948 t.connsWithAllPieces[p] = struct{}{}
2951 func (t *Torrent) deleteConnWithAllPieces(p *Peer) bool {
2952 _, ok := t.connsWithAllPieces[p]
2953 delete(t.connsWithAllPieces, p)
2957 func (t *Torrent) numActivePeers() int {
2958 return len(t.conns) + len(t.webSeeds)
2961 func (t *Torrent) hasStorageCap() bool {
2962 f := t.storage.Capacity
2970 func (t *Torrent) pieceIndexOfRequestIndex(ri RequestIndex) pieceIndex {
2971 return pieceIndex(ri / t.chunksPerRegularPiece())
2974 func (t *Torrent) iterUndirtiedRequestIndexesInPiece(
2975 reuseIter *typedRoaring.Iterator[RequestIndex],
2977 f func(RequestIndex),
2979 reuseIter.Initialize(&t.dirtyChunks)
2980 pieceRequestIndexOffset := t.pieceRequestIndexOffset(piece)
2981 iterBitmapUnsetInRange(
2983 pieceRequestIndexOffset, pieceRequestIndexOffset+t.pieceNumChunks(piece),
2988 type requestState struct {
2993 // Returns an error if a received chunk is out of bounds in someway.
2994 func (t *Torrent) checkValidReceiveChunk(r Request) error {
2996 return errors.New("torrent missing info")
2998 if int(r.Index) >= t.numPieces() {
2999 return fmt.Errorf("chunk index %v, torrent num pieces %v", r.Index, t.numPieces())
3001 pieceLength := t.pieceLength(pieceIndex(r.Index))
3002 if r.Begin >= pieceLength {
3003 return fmt.Errorf("chunk begins beyond end of piece (%v >= %v)", r.Begin, pieceLength)
3005 // We could check chunk lengths here, but chunk request size is not changed often, and tricky
3006 // for peers to manipulate as they need to send potentially large buffers to begin with. There
3007 // should be considerable checks elsewhere for this case due to the network overhead. We should
3008 // catch most of the overflow manipulation stuff by checking index and begin above.
3012 func (t *Torrent) peerConnsWithDialAddrPort(target netip.AddrPort) (ret []*PeerConn) {
3013 for pc := range t.conns {
3014 dialAddr, err := pc.remoteDialAddrPort()
3018 if dialAddr != target {
3021 ret = append(ret, pc)
3026 func wrapUtHolepunchMsgForPeerConn(
3027 recipient *PeerConn,
3028 msg utHolepunch.Msg,
3030 extendedPayload, err := msg.MarshalBinary()
3036 ExtendedID: MapMustGet(recipient.PeerExtensionIDs, utHolepunch.ExtensionName),
3037 ExtendedPayload: extendedPayload,
3041 func sendUtHolepunchMsg(
3043 msgType utHolepunch.MsgType,
3044 addrPort netip.AddrPort,
3045 errCode utHolepunch.ErrCode,
3047 holepunchMsg := utHolepunch.Msg{
3052 incHolepunchMessagesSent(holepunchMsg)
3053 ppMsg := wrapUtHolepunchMsgForPeerConn(pc, holepunchMsg)
3057 func incHolepunchMessages(msg utHolepunch.Msg, verb string) {
3060 "holepunch %v %v messages %v",
3062 addrPortProtocolStr(msg.AddrPort),
3069 func incHolepunchMessagesReceived(msg utHolepunch.Msg) {
3070 incHolepunchMessages(msg, "received")
3073 func incHolepunchMessagesSent(msg utHolepunch.Msg) {
3074 incHolepunchMessages(msg, "sent")
3077 func (t *Torrent) handleReceivedUtHolepunchMsg(msg utHolepunch.Msg, sender *PeerConn) error {
3078 incHolepunchMessagesReceived(msg)
3079 switch msg.MsgType {
3080 case utHolepunch.Rendezvous:
3081 t.logger.Printf("got holepunch rendezvous request for %v from %p", msg.AddrPort, sender)
3082 sendMsg := sendUtHolepunchMsg
3083 senderAddrPort, err := sender.remoteDialAddrPort()
3085 sender.logger.Levelf(
3087 "error getting ut_holepunch rendezvous sender's dial address: %v",
3090 // There's no better error code. The sender's address itself is invalid. I don't see
3091 // this error message being appropriate anywhere else anyway.
3092 sendMsg(sender, utHolepunch.Error, msg.AddrPort, utHolepunch.NoSuchPeer)
3094 targets := t.peerConnsWithDialAddrPort(msg.AddrPort)
3095 if len(targets) == 0 {
3096 sendMsg(sender, utHolepunch.Error, msg.AddrPort, utHolepunch.NotConnected)
3099 for _, pc := range targets {
3100 if !pc.supportsExtension(utHolepunch.ExtensionName) {
3101 sendMsg(sender, utHolepunch.Error, msg.AddrPort, utHolepunch.NoSupport)
3104 sendMsg(sender, utHolepunch.Connect, msg.AddrPort, 0)
3105 sendMsg(pc, utHolepunch.Connect, senderAddrPort, 0)
3108 case utHolepunch.Connect:
3109 holepunchAddr := msg.AddrPort
3110 t.logger.Printf("got holepunch connect request for %v from %p", holepunchAddr, sender)
3111 if g.MapContains(t.cl.undialableWithoutHolepunch, holepunchAddr) {
3112 setAdd(&t.cl.undialableWithoutHolepunchDialedAfterHolepunchConnect, holepunchAddr)
3113 if g.MapContains(t.cl.accepted, holepunchAddr) {
3114 setAdd(&t.cl.probablyOnlyConnectedDueToHolepunch, holepunchAddr)
3117 opts := outgoingConnOpts{
3120 Source: PeerSourceUtHolepunch,
3121 PexPeerFlags: sender.pex.remoteLiveConns[msg.AddrPort].UnwrapOrZeroValue(),
3124 // Don't attempt to start our own rendezvous if we fail to connect.
3125 skipHolepunchRendezvous: true,
3126 receivedHolepunchConnect: true,
3127 // Assume that the other end initiated the rendezvous, and will use our preferred
3128 // encryption. So we will act normally.
3129 HeaderObfuscationPolicy: t.cl.config.HeaderObfuscationPolicy,
3131 initiateConn(opts, true)
3133 case utHolepunch.Error:
3134 torrent.Add("holepunch error messages received", 1)
3135 t.logger.Levelf(log.Debug, "received ut_holepunch error message from %v: %v", sender, msg.ErrCode)
3138 return fmt.Errorf("unhandled msg type %v", msg.MsgType)
3142 func addrPortProtocolStr(addrPort netip.AddrPort) string {
3143 addr := addrPort.Addr()
3154 func (t *Torrent) trySendHolepunchRendezvous(addrPort netip.AddrPort) error {
3156 for pc := range t.conns {
3157 if !pc.supportsExtension(utHolepunch.ExtensionName) {
3160 if pc.supportsExtension(pp.ExtensionNamePex) {
3161 if !g.MapContains(pc.pex.remoteLiveConns, addrPort) {
3165 t.logger.Levelf(log.Debug, "sent ut_holepunch rendezvous message to %v for %v", pc, addrPort)
3166 sendUtHolepunchMsg(pc, utHolepunch.Rendezvous, addrPort, 0)
3170 return errors.New("no eligible relays")
3175 func (t *Torrent) numHalfOpenAttempts() (num int) {
3176 for _, attempts := range t.halfOpen {
3177 num += len(attempts)
3182 func (t *Torrent) getDialTimeoutUnlocked() time.Duration {
3186 return t.dialTimeout()
3189 func (t *Torrent) canonicalShortInfohash() *infohash.T {
3191 return &t.infoHash.Value
3193 return t.infoHashV2.UnwrapPtr().ToShort()
3196 func (t *Torrent) eachShortInfohash(each func(short [20]byte)) {
3197 if t.infoHash.Value == *t.infoHashV2.Value.ToShort() {
3198 // This includes zero values, since they both should not be zero. Plus Option should not
3199 // allow non-zero values for None.
3200 panic("v1 and v2 info hashes should not be the same")
3203 each(t.infoHash.Value)
3205 if t.infoHashV2.Ok {
3206 v2Short := *t.infoHashV2.Value.ToShort()
3211 func (t *Torrent) getFileByPiecesRoot(hash [32]byte) *File {
3212 for _, f := range *t.files {
3213 if f.piecesRoot.Unwrap() == hash {
3220 func (t *Torrent) pieceLayers() (pieceLayers map[string]string) {
3225 g.MakeMapWithCap(&pieceLayers, len(files))
3227 for _, f := range files {
3228 if !f.piecesRoot.Ok {
3231 key := f.piecesRoot.Value
3232 var value strings.Builder
3233 for i := f.BeginPieceIndex(); i < f.EndPieceIndex(); i++ {
3234 hashOpt := t.piece(i).hashV2
3236 // All hashes must be present. This implementation should handle missing files, so move on to the next file.
3239 value.Write(hashOpt.Value[:])
3241 if value.Len() == 0 {
3242 // Non-empty files are not recorded in piece layers.
3245 // If multiple files have the same root that shouldn't matter.
3246 pieceLayers[string(key[:])] = value.String()