8 "golang.org/x/time/rate"
17 "github.com/RoaringBitmap/roaring"
18 "github.com/anacrolix/chansync"
19 . "github.com/anacrolix/generics"
20 "github.com/anacrolix/log"
21 "github.com/anacrolix/missinggo/iter"
22 "github.com/anacrolix/missinggo/v2/bitmap"
23 "github.com/anacrolix/multiless"
24 "github.com/anacrolix/torrent/bencode"
25 "github.com/anacrolix/torrent/metainfo"
26 "github.com/anacrolix/torrent/mse"
27 pp "github.com/anacrolix/torrent/peer_protocol"
28 request_strategy "github.com/anacrolix/torrent/request-strategy"
29 "github.com/anacrolix/torrent/typed-roaring"
32 type PeerSource string
35 PeerSourceTracker = "Tr"
36 PeerSourceIncoming = "I"
37 PeerSourceDhtGetPeers = "Hg" // Peers we found by searching a DHT.
38 PeerSourceDhtAnnouncePeer = "Ha" // Peers that were announced to us by a DHT.
40 // The peer was given directly, such as through a magnet link.
41 PeerSourceDirect = "M"
44 type peerRequestState struct {
48 type PeerRemoteAddr interface {
53 // Since we have to store all the requests in memory, we can't reasonably exceed what could be
54 // indexed with the memory space available.
59 // First to ensure 64-bit alignment for atomics. See #262.
69 RemoteAddr PeerRemoteAddr
70 bannableAddr Option[bannableAddr]
71 // True if the connection is operating over MSE obfuscation.
73 cryptoMethod mse.CryptoMethod
76 closed chansync.SetOnce
77 // Set true after we've added our ConnStats generated during handshake to
78 // other ConnStat instances as determined when the *Torrent became known.
79 reconciledHandshakeStats bool
81 lastMessageReceived time.Time
82 completedHandshake time.Time
83 lastUsefulChunkReceived time.Time
84 lastChunkSent time.Time
86 // Stuff controlled by the local peer.
87 needRequestUpdate string
88 requestState request_strategy.PeerRequestState
89 updateRequestsTimer *time.Timer
90 lastRequestUpdate time.Time
91 peakRequests maxRequests
92 lastBecameInterested time.Time
93 priorInterest time.Duration
95 lastStartedExpectingToReceiveChunks time.Time
96 cumulativeExpectedToReceiveChunks time.Duration
97 _chunksReceivedWhileExpecting int64
100 piecesReceivedSinceLastRequestUpdate maxRequests
101 maxPiecesReceivedBetweenRequestUpdates maxRequests
102 // Chunks that we might reasonably expect to receive from the peer. Due to latency, buffering,
103 // and implementation differences, we may receive chunks that are no longer in the set of
104 // requests actually want. This could use a roaring.BSI if the memory use becomes noticeable.
105 validReceiveChunks map[RequestIndex]int
106 // Indexed by metadata piece, set to true if posted and pending a
108 metadataRequests []bool
109 sentHaves bitmap.Bitmap
111 // Stuff controlled by the remote peer.
114 peerRequests map[Request]*peerRequestState
115 PeerPrefersEncryption bool // as indicated by 'e' field in extension handshake
117 // The highest possible number of pieces the torrent could have based on
118 // communication with the peer. Generally only useful until we have the
120 peerMinPieces pieceIndex
121 // Pieces we've accepted chunks for from the peer.
122 peerTouchedPieces map[pieceIndex]struct{}
123 peerAllowedFast typedRoaring.Bitmap[pieceIndex]
125 PeerMaxRequests maxRequests // Maximum pending requests the peer allows.
126 PeerExtensionIDs map[pp.ExtensionName]pp.ExtensionNumber
127 PeerClientName atomic.Value
132 type peerRequests = orderedBitmap[RequestIndex]
134 func (p *Peer) initRequestState() {
135 p.requestState.Requests = &peerRequests{}
138 // Maintains the state of a BitTorrent-protocol based connection with a peer.
139 type PeerConn struct {
142 // A string that should identify the PeerConn's net.Conn endpoints. The net.Conn could
143 // be wrapping WebRTC, uTP, or TCP etc. Used in writing the conn status for peers.
148 PeerExtensionBytes pp.PeerExtensionBits
150 // The actual Conn, used for closing, and setting socket options. Do not use methods on this
151 // while holding any mutexes.
153 // The Reader and Writer for this Conn, with hooks installed for stats,
154 // limiting, deadlines etc.
158 messageWriter peerConnMsgWriter
160 uploadTimer *time.Timer
163 // The pieces the peer has claimed to have.
164 _peerPieces roaring.Bitmap
165 // The peer has everything. This can occur due to a special message, when
166 // we may not even know the number of pieces in the torrent yet.
170 func (cn *PeerConn) connStatusString() string {
171 return fmt.Sprintf("%+-55q %s %s", cn.PeerID, cn.PeerExtensionBytes, cn.connString)
174 func (cn *Peer) updateExpectingChunks() {
175 if cn.expectingChunks() {
176 if cn.lastStartedExpectingToReceiveChunks.IsZero() {
177 cn.lastStartedExpectingToReceiveChunks = time.Now()
180 if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
181 cn.cumulativeExpectedToReceiveChunks += time.Since(cn.lastStartedExpectingToReceiveChunks)
182 cn.lastStartedExpectingToReceiveChunks = time.Time{}
187 func (cn *Peer) expectingChunks() bool {
188 if cn.requestState.Requests.IsEmpty() {
191 if !cn.requestState.Interested {
197 haveAllowedFastRequests := false
198 cn.peerAllowedFast.Iterate(func(i pieceIndex) bool {
199 haveAllowedFastRequests = roaringBitmapRangeCardinality[RequestIndex](
200 cn.requestState.Requests,
201 cn.t.pieceRequestIndexOffset(i),
202 cn.t.pieceRequestIndexOffset(i+1),
204 return !haveAllowedFastRequests
206 return haveAllowedFastRequests
209 func (cn *Peer) remoteChokingPiece(piece pieceIndex) bool {
210 return cn.peerChoking && !cn.peerAllowedFast.Contains(piece)
213 // Returns true if the connection is over IPv6.
214 func (cn *PeerConn) ipv6() bool {
219 return len(ip) == net.IPv6len
222 // Returns true the if the dialer/initiator has the lower client peer ID. TODO: Find the
223 // specification for this.
224 func (cn *PeerConn) isPreferredDirection() bool {
225 return bytes.Compare(cn.t.cl.peerID[:], cn.PeerID[:]) < 0 == cn.outgoing
228 // Returns whether the left connection should be preferred over the right one,
229 // considering only their networking properties. If ok is false, we can't
231 func (l *PeerConn) hasPreferredNetworkOver(r *PeerConn) bool {
232 var ml multiless.Computation
233 ml = ml.Bool(r.isPreferredDirection(), l.isPreferredDirection())
234 ml = ml.Bool(l.utp(), r.utp())
235 ml = ml.Bool(r.ipv6(), l.ipv6())
239 func (cn *Peer) cumInterest() time.Duration {
240 ret := cn.priorInterest
241 if cn.requestState.Interested {
242 ret += time.Since(cn.lastBecameInterested)
247 func (cn *PeerConn) peerHasAllPieces() (all, known bool) {
248 if cn.peerSentHaveAll {
251 if !cn.t.haveInfo() {
254 return cn._peerPieces.GetCardinality() == uint64(cn.t.numPieces()), true
257 func (cn *Peer) locker() *lockWithDeferreds {
258 return cn.t.cl.locker()
261 func (cn *Peer) supportsExtension(ext pp.ExtensionName) bool {
262 _, ok := cn.PeerExtensionIDs[ext]
266 // The best guess at number of pieces in the torrent for this peer.
267 func (cn *Peer) bestPeerNumPieces() pieceIndex {
269 return cn.t.numPieces()
271 return cn.peerMinPieces
274 func (cn *Peer) completedString() string {
275 have := pieceIndex(cn.peerPieces().GetCardinality())
276 if all, _ := cn.peerHasAllPieces(); all {
277 have = cn.bestPeerNumPieces()
279 return fmt.Sprintf("%d/%d", have, cn.bestPeerNumPieces())
282 func (cn *PeerConn) onGotInfo(info *metainfo.Info) {
283 cn.setNumPieces(info.NumPieces())
286 // Correct the PeerPieces slice length. Return false if the existing slice is invalid, such as by
287 // receiving badly sized BITFIELD, or invalid HAVE messages.
288 func (cn *PeerConn) setNumPieces(num pieceIndex) {
289 cn._peerPieces.RemoveRange(bitmap.BitRange(num), bitmap.ToEnd)
290 cn.peerPiecesChanged()
293 func (cn *PeerConn) peerPieces() *roaring.Bitmap {
294 return &cn._peerPieces
297 func eventAgeString(t time.Time) string {
301 return fmt.Sprintf("%.2fs ago", time.Since(t).Seconds())
304 func (cn *PeerConn) connectionFlags() (ret string) {
306 ret += string([]byte{b})
308 if cn.cryptoMethod == mse.CryptoMethodRC4 {
310 } else if cn.headerEncrypted {
313 ret += string(cn.Discovery)
320 func (cn *PeerConn) utp() bool {
321 return parseNetworkString(cn.Network).Udp
324 // Inspired by https://github.com/transmission/transmission/wiki/Peer-Status-Text.
325 func (cn *Peer) statusFlags() (ret string) {
327 ret += string([]byte{b})
329 if cn.requestState.Interested {
336 ret += cn.connectionFlags()
338 if cn.peerInterested {
347 func (cn *Peer) downloadRate() float64 {
348 num := cn._stats.BytesReadUsefulData.Int64()
352 return float64(num) / cn.totalExpectingTime().Seconds()
355 func (cn *Peer) DownloadRate() float64 {
357 defer cn.locker().Unlock()
359 return cn.downloadRate()
362 func (cn *Peer) iterContiguousPieceRequests(f func(piece pieceIndex, count int)) {
363 var last Option[pieceIndex]
365 next := func(item Option[pieceIndex]) {
376 cn.requestState.Requests.Iterate(func(requestIndex request_strategy.RequestIndex) bool {
377 next(Some(cn.t.pieceIndexOfRequestIndex(requestIndex)))
380 next(None[pieceIndex]())
383 func (cn *Peer) writeStatus(w io.Writer, t *Torrent) {
384 // \t isn't preserved in <pre> blocks?
385 if cn.closed.IsSet() {
386 fmt.Fprint(w, "CLOSED: ")
388 fmt.Fprintln(w, cn.connStatusString())
389 prio, err := cn.peerPriority()
390 prioStr := fmt.Sprintf("%08x", prio)
392 prioStr += ": " + err.Error()
394 fmt.Fprintf(w, " bep40-prio: %v\n", prioStr)
395 fmt.Fprintf(w, " last msg: %s, connected: %s, last helpful: %s, itime: %s, etime: %s\n",
396 eventAgeString(cn.lastMessageReceived),
397 eventAgeString(cn.completedHandshake),
398 eventAgeString(cn.lastHelpful()),
400 cn.totalExpectingTime(),
403 " %s completed, %d pieces touched, good chunks: %v/%v:%v reqq: %d+%v/(%d/%d):%d/%d, flags: %s, dr: %.1f KiB/s\n",
404 cn.completedString(),
405 len(cn.peerTouchedPieces),
406 &cn._stats.ChunksReadUseful,
407 &cn._stats.ChunksRead,
408 &cn._stats.ChunksWritten,
409 cn.requestState.Requests.GetCardinality(),
410 cn.requestState.Cancelled.GetCardinality(),
411 cn.nominalMaxRequests(),
413 len(cn.peerRequests),
416 cn.downloadRate()/(1<<10),
418 fmt.Fprintf(w, " requested pieces:")
419 cn.iterContiguousPieceRequests(func(piece pieceIndex, count int) {
420 fmt.Fprintf(w, " %v(%v)", piece, count)
425 func (p *Peer) close() {
429 if p.updateRequestsTimer != nil {
430 p.updateRequestsTimer.Stop()
434 p.t.decPeerPieceAvailability(p)
436 for _, f := range p.callbacks.PeerClosed {
441 func (cn *PeerConn) onClose() {
442 if cn.pex.IsEnabled() {
449 if cb := cn.callbacks.PeerConnClosed; cb != nil {
454 // Peer definitely has a piece, for purposes of requesting. So it's not sufficient that we think
455 // they do (known=true).
456 func (cn *Peer) peerHasPiece(piece pieceIndex) bool {
457 if all, known := cn.peerHasAllPieces(); all && known {
460 return cn.peerPieces().ContainsInt(piece)
463 // 64KiB, but temporarily less to work around an issue with WebRTC. TODO: Update when
464 // https://github.com/pion/datachannel/issues/59 is fixed.
466 writeBufferHighWaterLen = 1 << 15
467 writeBufferLowWaterLen = writeBufferHighWaterLen / 2
470 // Writes a message into the write buffer. Returns whether it's okay to keep writing. Writing is
471 // done asynchronously, so it may be that we're not able to honour backpressure from this method.
472 func (cn *PeerConn) write(msg pp.Message) bool {
473 torrent.Add(fmt.Sprintf("messages written of type %s", msg.Type.String()), 1)
474 // We don't need to track bytes here because the connection's Writer has that behaviour injected
475 // (although there's some delay between us buffering the message, and the connection writer
476 // flushing it out.).
477 notFull := cn.messageWriter.write(msg)
478 // Last I checked only Piece messages affect stats, and we don't write those.
484 func (cn *PeerConn) requestMetadataPiece(index int) {
485 eID := cn.PeerExtensionIDs[pp.ExtensionNameMetadata]
486 if eID == pp.ExtensionDeleteNumber {
489 if index < len(cn.metadataRequests) && cn.metadataRequests[index] {
492 cn.logger.WithDefaultLevel(log.Debug).Printf("requesting metadata piece %d", index)
493 cn.write(pp.MetadataExtensionRequestMsg(eID, index))
494 for index >= len(cn.metadataRequests) {
495 cn.metadataRequests = append(cn.metadataRequests, false)
497 cn.metadataRequests[index] = true
500 func (cn *PeerConn) requestedMetadataPiece(index int) bool {
501 return index < len(cn.metadataRequests) && cn.metadataRequests[index]
505 interestedMsgLen = len(pp.Message{Type: pp.Interested}.MustMarshalBinary())
506 requestMsgLen = len(pp.Message{Type: pp.Request}.MustMarshalBinary())
507 // This is the maximum request count that could fit in the write buffer if it's at or below the
508 // low water mark when we run maybeUpdateActualRequestState.
509 maxLocalToRemoteRequests = (writeBufferHighWaterLen - writeBufferLowWaterLen - interestedMsgLen) / requestMsgLen
512 // The actual value to use as the maximum outbound requests.
513 func (cn *Peer) nominalMaxRequests() maxRequests {
514 return maxInt(1, minInt(cn.PeerMaxRequests, cn.peakRequests*2, maxLocalToRemoteRequests))
517 func (cn *Peer) totalExpectingTime() (ret time.Duration) {
518 ret = cn.cumulativeExpectedToReceiveChunks
519 if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
520 ret += time.Since(cn.lastStartedExpectingToReceiveChunks)
525 func (cn *PeerConn) onPeerSentCancel(r Request) {
526 if _, ok := cn.peerRequests[r]; !ok {
527 torrent.Add("unexpected cancels received", 1)
530 if cn.fastEnabled() {
533 delete(cn.peerRequests, r)
537 func (cn *PeerConn) choke(msg messageWriter) (more bool) {
542 more = msg(pp.Message{
545 if !cn.fastEnabled() {
546 cn.peerRequests = nil
551 func (cn *PeerConn) unchoke(msg func(pp.Message) bool) bool {
556 return msg(pp.Message{
561 func (cn *Peer) setInterested(interested bool) bool {
562 if cn.requestState.Interested == interested {
565 cn.requestState.Interested = interested
567 cn.lastBecameInterested = time.Now()
568 } else if !cn.lastBecameInterested.IsZero() {
569 cn.priorInterest += time.Since(cn.lastBecameInterested)
571 cn.updateExpectingChunks()
572 // log.Printf("%p: setting interest: %v", cn, interested)
573 return cn.writeInterested(interested)
576 func (pc *PeerConn) writeInterested(interested bool) bool {
577 return pc.write(pp.Message{
578 Type: func() pp.MessageType {
582 return pp.NotInterested
588 // The function takes a message to be sent, and returns true if more messages
590 type messageWriter func(pp.Message) bool
592 // This function seems to only used by Peer.request. It's all logic checks, so maybe we can no-op it
593 // when we want to go fast.
594 func (cn *Peer) shouldRequest(r RequestIndex) error {
595 pi := cn.t.pieceIndexOfRequestIndex(r)
596 if cn.requestState.Cancelled.Contains(r) {
597 return errors.New("request is cancelled and waiting acknowledgement")
599 if !cn.peerHasPiece(pi) {
600 return errors.New("requesting piece peer doesn't have")
602 if !cn.t.peerIsActive(cn) {
603 panic("requesting but not in active conns")
605 if cn.closed.IsSet() {
606 panic("requesting when connection is closed")
608 if cn.t.hashingPiece(pi) {
609 panic("piece is being hashed")
611 if cn.t.pieceQueuedForHash(pi) {
612 panic("piece is queued for hash")
614 if cn.peerChoking && !cn.peerAllowedFast.Contains(pi) {
615 // This could occur if we made a request with the fast extension, and then got choked and
616 // haven't had the request rejected yet.
617 if !cn.requestState.Requests.Contains(r) {
618 panic("peer choking and piece not allowed fast")
624 func (cn *Peer) mustRequest(r RequestIndex) bool {
625 more, err := cn.request(r)
632 func (cn *Peer) request(r RequestIndex) (more bool, err error) {
633 if err := cn.shouldRequest(r); err != nil {
636 if cn.requestState.Requests.Contains(r) {
639 if maxRequests(cn.requestState.Requests.GetCardinality()) >= cn.nominalMaxRequests() {
640 return true, errors.New("too many outstanding requests")
642 cn.requestState.Requests.Add(r)
643 if cn.validReceiveChunks == nil {
644 cn.validReceiveChunks = make(map[RequestIndex]int)
646 cn.validReceiveChunks[r]++
647 cn.t.requestState[r] = requestState{
651 cn.updateExpectingChunks()
652 ppReq := cn.t.requestIndexToRequest(r)
653 for _, f := range cn.callbacks.SentRequest {
654 f(PeerRequestEvent{cn, ppReq})
656 return cn.peerImpl._request(ppReq), nil
659 func (me *PeerConn) _request(r Request) bool {
660 return me.write(pp.Message{
668 func (me *Peer) cancel(r RequestIndex) {
669 if !me.deleteRequest(r) {
670 panic("request not existing should have been guarded")
673 if !me.requestState.Cancelled.CheckedAdd(r) {
674 panic("request already cancelled")
678 if me.isLowOnRequests() {
679 me.updateRequests("Peer.cancel")
683 func (me *PeerConn) _cancel(r RequestIndex) bool {
684 me.write(makeCancelMessage(me.t.requestIndexToRequest(r)))
685 // Transmission does not send rejects for received cancels. See
686 // https://github.com/transmission/transmission/pull/2275.
687 return me.fastEnabled() && !me.remoteIsTransmission()
690 func (cn *PeerConn) fillWriteBuffer() {
691 if cn.messageWriter.writeBuffer.Len() > writeBufferLowWaterLen {
692 // Fully committing to our max requests requires sufficient space (see
693 // maxLocalToRemoteRequests). Flush what we have instead. We also prefer always to make
694 // requests than to do PEX or upload, so we short-circuit before handling those. Any update
695 // request reason will not be cleared, so we'll come right back here when there's space. We
696 // can't do this in maybeUpdateActualRequestState because it's a method on Peer and has no
697 // knowledge of write buffers.
699 cn.maybeUpdateActualRequestState()
700 if cn.pex.IsEnabled() {
701 if flow := cn.pex.Share(cn.write); !flow {
708 func (cn *PeerConn) have(piece pieceIndex) {
709 if cn.sentHaves.Get(bitmap.BitIndex(piece)) {
714 Index: pp.Integer(piece),
716 cn.sentHaves.Add(bitmap.BitIndex(piece))
719 func (cn *PeerConn) postBitfield() {
720 if cn.sentHaves.Len() != 0 {
721 panic("bitfield must be first have-related message sent")
723 if !cn.t.haveAnyPieces() {
728 Bitfield: cn.t.bitfield(),
730 cn.sentHaves = bitmap.Bitmap{cn.t._completedPieces.Clone()}
733 // Sets a reason to update requests, and if there wasn't already one, handle it.
734 func (cn *Peer) updateRequests(reason string) {
735 if cn.needRequestUpdate != "" {
738 if reason != peerUpdateRequestsTimerReason && !cn.isLowOnRequests() {
741 cn.needRequestUpdate = reason
742 cn.handleUpdateRequests()
745 func (cn *PeerConn) handleUpdateRequests() {
746 // The writer determines the request state as needed when it can write.
750 // Emits the indices in the Bitmaps bms in order, never repeating any index.
751 // skip is mutated during execution, and its initial values will never be
753 func iterBitmapsDistinct(skip *bitmap.Bitmap, bms ...bitmap.Bitmap) iter.Func {
754 return func(cb iter.Callback) {
755 for _, bm := range bms {
757 func(_i interface{}) bool {
759 if skip.Contains(bitmap.BitIndex(i)) {
762 skip.Add(bitmap.BitIndex(i))
773 func (cn *Peer) peerPiecesChanged() {
774 cn.t.maybeDropMutuallyCompletePeer(cn)
777 func (cn *PeerConn) raisePeerMinPieces(newMin pieceIndex) {
778 if newMin > cn.peerMinPieces {
779 cn.peerMinPieces = newMin
783 func (cn *PeerConn) peerSentHave(piece pieceIndex) error {
784 if cn.t.haveInfo() && piece >= cn.t.numPieces() || piece < 0 {
785 return errors.New("invalid piece")
787 if cn.peerHasPiece(piece) {
790 cn.raisePeerMinPieces(piece + 1)
791 if !cn.peerHasPiece(piece) {
792 cn.t.incPieceAvailability(piece)
794 cn._peerPieces.Add(uint32(piece))
795 if cn.t.wantPieceIndex(piece) {
796 cn.updateRequests("have")
798 cn.peerPiecesChanged()
802 func (cn *PeerConn) peerSentBitfield(bf []bool) error {
804 panic("expected bitfield length divisible by 8")
806 // We know that the last byte means that at most the last 7 bits are wasted.
807 cn.raisePeerMinPieces(pieceIndex(len(bf) - 7))
808 if cn.t.haveInfo() && len(bf) > int(cn.t.numPieces()) {
809 // Ignore known excess pieces.
810 bf = bf[:cn.t.numPieces()]
812 bm := boolSliceToBitmap(bf)
813 if cn.t.haveInfo() && pieceIndex(bm.GetCardinality()) == cn.t.numPieces() {
814 cn.onPeerHasAllPieces()
818 cn.raisePeerMinPieces(pieceIndex(bm.Maximum()) + 1)
820 shouldUpdateRequests := false
821 if cn.peerSentHaveAll {
822 if !cn.t.deleteConnWithAllPieces(&cn.Peer) {
825 cn.peerSentHaveAll = false
826 if !cn._peerPieces.IsEmpty() {
827 panic("if peer has all, we expect no individual peer pieces to be set")
830 bm.Xor(&cn._peerPieces)
832 cn.peerSentHaveAll = false
833 // bm is now 'on' for pieces that are changing
834 bm.Iterate(func(x uint32) bool {
836 if cn._peerPieces.Contains(x) {
837 // Then we must be losing this piece
838 cn.t.decPieceAvailability(pi)
840 if !shouldUpdateRequests && cn.t.wantPieceIndex(pieceIndex(x)) {
841 shouldUpdateRequests = true
843 // We must be gaining this piece
844 cn.t.incPieceAvailability(pieceIndex(x))
848 // Apply the changes. If we had everything previously, this should be empty, so xor is the same
850 cn._peerPieces.Xor(&bm)
851 if shouldUpdateRequests {
852 cn.updateRequests("bitfield")
854 // We didn't guard this before, I see no reason to do it now.
855 cn.peerPiecesChanged()
859 func (cn *PeerConn) onPeerHasAllPieces() {
862 cn._peerPieces.Iterate(func(x uint32) bool {
863 t.decPieceAvailability(pieceIndex(x))
867 t.addConnWithAllPieces(&cn.Peer)
868 cn.peerSentHaveAll = true
869 cn._peerPieces.Clear()
870 if !cn.t._pendingPieces.IsEmpty() {
871 cn.updateRequests("Peer.onPeerHasAllPieces")
873 cn.peerPiecesChanged()
876 func (cn *PeerConn) onPeerSentHaveAll() error {
877 cn.onPeerHasAllPieces()
881 func (cn *PeerConn) peerSentHaveNone() error {
882 if cn.peerSentHaveAll {
883 cn.t.decPeerPieceAvailability(&cn.Peer)
885 cn._peerPieces.Clear()
886 cn.peerSentHaveAll = false
887 cn.peerPiecesChanged()
891 func (c *PeerConn) requestPendingMetadata() {
895 if c.PeerExtensionIDs[pp.ExtensionNameMetadata] == 0 {
896 // Peer doesn't support this.
899 // Request metadata pieces that we don't have in a random order.
901 for index := 0; index < c.t.metadataPieceCount(); index++ {
902 if !c.t.haveMetadataPiece(index) && !c.requestedMetadataPiece(index) {
903 pending = append(pending, index)
906 rand.Shuffle(len(pending), func(i, j int) { pending[i], pending[j] = pending[j], pending[i] })
907 for _, i := range pending {
908 c.requestMetadataPiece(i)
912 func (cn *PeerConn) wroteMsg(msg *pp.Message) {
913 torrent.Add(fmt.Sprintf("messages written of type %s", msg.Type.String()), 1)
914 if msg.Type == pp.Extended {
915 for name, id := range cn.PeerExtensionIDs {
916 if id != msg.ExtendedID {
919 torrent.Add(fmt.Sprintf("Extended messages written for protocol %q", name), 1)
922 cn.allStats(func(cs *ConnStats) { cs.wroteMsg(msg) })
925 // After handshake, we know what Torrent and Client stats to include for a
927 func (cn *Peer) postHandshakeStats(f func(*ConnStats)) {
933 // All ConnStats that include this connection. Some objects are not known
934 // until the handshake is complete, after which it's expected to reconcile the
936 func (cn *Peer) allStats(f func(*ConnStats)) {
938 if cn.reconciledHandshakeStats {
939 cn.postHandshakeStats(f)
943 func (cn *PeerConn) wroteBytes(n int64) {
944 cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesWritten }))
947 func (cn *Peer) readBytes(n int64) {
948 cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesRead }))
951 // Returns whether the connection could be useful to us. We're seeding and
952 // they want data, we don't have metainfo and they can provide it, etc.
953 func (c *Peer) useful() bool {
955 if c.closed.IsSet() {
959 return c.supportsExtension("ut_metadata")
961 if t.seeding() && c.peerInterested {
964 if c.peerHasWantedPieces() {
970 func (c *Peer) lastHelpful() (ret time.Time) {
971 ret = c.lastUsefulChunkReceived
972 if c.t.seeding() && c.lastChunkSent.After(ret) {
973 ret = c.lastChunkSent
978 func (c *PeerConn) fastEnabled() bool {
979 return c.PeerExtensionBytes.SupportsFast() && c.t.cl.config.Extensions.SupportsFast()
982 func (c *PeerConn) reject(r Request) {
983 if !c.fastEnabled() {
984 panic("fast not enabled")
986 c.write(r.ToMsg(pp.Reject))
987 delete(c.peerRequests, r)
990 func (c *PeerConn) maximumPeerRequestChunkLength() (_ Option[int]) {
991 uploadRateLimiter := c.t.cl.config.UploadRateLimiter
992 if uploadRateLimiter.Limit() == rate.Inf {
995 return Some(uploadRateLimiter.Burst())
998 // startFetch is for testing purposes currently.
999 func (c *PeerConn) onReadRequest(r Request, startFetch bool) error {
1000 requestedChunkLengths.Add(strconv.FormatUint(r.Length.Uint64(), 10), 1)
1001 if _, ok := c.peerRequests[r]; ok {
1002 torrent.Add("duplicate requests received", 1)
1003 if c.fastEnabled() {
1004 return errors.New("received duplicate request with fast enabled")
1009 torrent.Add("requests received while choking", 1)
1010 if c.fastEnabled() {
1011 torrent.Add("requests rejected while choking", 1)
1016 // TODO: What if they've already requested this?
1017 if len(c.peerRequests) >= localClientReqq {
1018 torrent.Add("requests received while queue full", 1)
1019 if c.fastEnabled() {
1022 // BEP 6 says we may close here if we choose.
1025 if opt := c.maximumPeerRequestChunkLength(); opt.Ok && int(r.Length) > opt.Value {
1026 err := fmt.Errorf("peer requested chunk too long (%v)", r.Length)
1027 c.logger.Levelf(log.Warning, err.Error())
1028 if c.fastEnabled() {
1035 if !c.t.havePiece(pieceIndex(r.Index)) {
1036 // TODO: Tell the peer we don't have the piece, and reject this request.
1037 requestsReceivedForMissingPieces.Add(1)
1038 return fmt.Errorf("peer requested piece we don't have: %v", r.Index.Int())
1040 // Check this after we know we have the piece, so that the piece length will be known.
1041 if r.Begin+r.Length > c.t.pieceLength(pieceIndex(r.Index)) {
1042 torrent.Add("bad requests received", 1)
1043 return errors.New("bad Request")
1045 if c.peerRequests == nil {
1046 c.peerRequests = make(map[Request]*peerRequestState, localClientReqq)
1048 value := &peerRequestState{}
1049 c.peerRequests[r] = value
1051 // TODO: Limit peer request data read concurrency.
1052 go c.peerRequestDataReader(r, value)
1057 func (c *PeerConn) peerRequestDataReader(r Request, prs *peerRequestState) {
1058 b, err := readPeerRequestData(r, c)
1060 defer c.locker().Unlock()
1062 c.peerRequestDataReadFailed(err, r)
1065 panic("data must be non-nil to trigger send")
1067 torrent.Add("peer request data read successes", 1)
1069 // This might be required for the error case too (#752 and #753).
1074 // If this is maintained correctly, we might be able to support optional synchronous reading for
1075 // chunk sending, the way it used to work.
1076 func (c *PeerConn) peerRequestDataReadFailed(err error, r Request) {
1077 torrent.Add("peer request data read failures", 1)
1078 logLevel := log.Warning
1079 if c.t.hasStorageCap() {
1080 // It's expected that pieces might drop. See
1081 // https://github.com/anacrolix/torrent/issues/702#issuecomment-1000953313.
1082 logLevel = log.Debug
1084 c.logger.WithDefaultLevel(logLevel).Printf("error reading chunk for peer Request %v: %v", r, err)
1085 if c.t.closed.IsSet() {
1088 i := pieceIndex(r.Index)
1089 if c.t.pieceComplete(i) {
1090 // There used to be more code here that just duplicated the following break. Piece
1091 // completions are currently cached, so I'm not sure how helpful this update is, except to
1092 // pull any completion changes pushed to the storage backend in failed reads that got us
1094 c.t.updatePieceCompletion(i)
1096 // We've probably dropped a piece from storage, but there's no way to communicate this to the
1097 // peer. If they ask for it again, we kick them allowing us to send them updated piece states if
1098 // we reconnect. TODO: Instead, we could just try to update them with Bitfield or HaveNone and
1099 // if they kick us for breaking protocol, on reconnect we will be compliant again (at least
1101 if c.fastEnabled() {
1105 // If fast isn't enabled, I think we would have wiped all peer requests when we last
1106 // choked, and requests while we're choking would be ignored. It could be possible that
1107 // a peer request data read completed concurrently to it being deleted elsewhere.
1108 c.logger.WithDefaultLevel(log.Warning).Printf("already choking peer, requests might not be rejected correctly")
1110 // Choking a non-fast peer should cause them to flush all their requests.
1115 func readPeerRequestData(r Request, c *PeerConn) ([]byte, error) {
1116 b := make([]byte, r.Length)
1117 p := c.t.info.Piece(int(r.Index))
1118 n, err := c.t.readAt(b, p.Offset()+int64(r.Begin))
1125 panic("expected error")
1131 func runSafeExtraneous(f func()) {
1139 func (c *PeerConn) logProtocolBehaviour(level log.Level, format string, arg ...interface{}) {
1140 c.logger.WithContextText(fmt.Sprintf(
1141 "peer id %q, ext v %q", c.PeerID, c.PeerClientName.Load(),
1142 )).SkipCallers(1).Levelf(level, format, arg...)
1145 // Processes incoming BitTorrent wire-protocol messages. The client lock is held upon entry and
1146 // exit. Returning will end the connection.
1147 func (c *PeerConn) mainReadLoop() (err error) {
1150 torrent.Add("connection.mainReadLoop returned with error", 1)
1152 torrent.Add("connection.mainReadLoop returned with no error", 1)
1158 decoder := pp.Decoder{
1159 R: bufio.NewReaderSize(c.r, 1<<17),
1160 MaxLength: 4 * pp.Integer(max(int64(t.chunkSize), defaultChunkSize)),
1168 err = decoder.Decode(&msg)
1170 if cb := c.callbacks.ReadMessage; cb != nil && err == nil {
1173 if t.closed.IsSet() || c.closed.IsSet() {
1179 c.lastMessageReceived = time.Now()
1181 receivedKeepalives.Add(1)
1184 messageTypesReceived.Add(msg.Type.String(), 1)
1185 if msg.Type.FastExtension() && !c.fastEnabled() {
1186 runSafeExtraneous(func() { torrent.Add("fast messages received when extension is disabled", 1) })
1187 return fmt.Errorf("received fast extension message (type=%v) but extension is disabled", msg.Type)
1194 if !c.fastEnabled() {
1195 c.deleteAllRequests("choked by non-fast PeerConn")
1197 // We don't decrement pending requests here, let's wait for the peer to either
1198 // reject or satisfy the outstanding requests. Additionally, some peers may unchoke
1199 // us and resume where they left off, we don't want to have piled on to those chunks
1200 // in the meanwhile. I think a peer's ability to abuse this should be limited: they
1201 // could let us request a lot of stuff, then choke us and never reject, but they're
1202 // only a single peer, our chunk balancing should smooth over this abuse.
1204 c.peerChoking = true
1205 c.updateExpectingChunks()
1208 // Some clients do this for some reason. Transmission doesn't error on this, so we
1209 // won't for consistency.
1210 c.logProtocolBehaviour(log.Debug, "received unchoke when already unchoked")
1213 c.peerChoking = false
1215 c.requestState.Requests.Iterate(func(x RequestIndex) bool {
1216 if !c.peerAllowedFast.Contains(c.t.pieceIndexOfRequestIndex(x)) {
1221 if preservedCount != 0 {
1222 // TODO: Yes this is a debug log but I'm not happy with the state of the logging lib
1224 c.logger.Levelf(log.Debug,
1225 "%v requests were preserved while being choked (fast=%v)",
1229 torrent.Add("requestsPreservedThroughChoking", int64(preservedCount))
1231 if !c.t._pendingPieces.IsEmpty() {
1232 c.updateRequests("unchoked")
1234 c.updateExpectingChunks()
1236 c.peerInterested = true
1238 case pp.NotInterested:
1239 c.peerInterested = false
1240 // We don't clear their requests since it isn't clear in the spec.
1241 // We'll probably choke them for this, which will clear them if
1242 // appropriate, and is clearly specified.
1244 err = c.peerSentHave(pieceIndex(msg.Index))
1246 err = c.peerSentBitfield(msg.Bitfield)
1248 r := newRequestFromMessage(&msg)
1249 err = c.onReadRequest(r, true)
1251 c.doChunkReadStats(int64(len(msg.Piece)))
1252 err = c.receiveChunk(&msg)
1253 if len(msg.Piece) == int(t.chunkSize) {
1254 t.chunkPool.Put(&msg.Piece)
1257 err = fmt.Errorf("receiving chunk: %w", err)
1260 req := newRequestFromMessage(&msg)
1261 c.onPeerSentCancel(req)
1263 ipa, ok := tryIpPortFromNetAddr(c.RemoteAddr)
1267 pingAddr := net.UDPAddr{
1272 pingAddr.Port = int(msg.Port)
1274 cl.eachDhtServer(func(s DhtServer) {
1275 go s.Ping(&pingAddr)
1278 torrent.Add("suggests received", 1)
1279 log.Fmsg("peer suggested piece %d", msg.Index).AddValues(c, msg.Index).LogLevel(log.Debug, c.t.logger)
1280 c.updateRequests("suggested")
1282 err = c.onPeerSentHaveAll()
1284 err = c.peerSentHaveNone()
1286 req := newRequestFromMessage(&msg)
1287 if !c.remoteRejectedRequest(c.t.requestIndexFromRequest(req)) {
1288 c.logger.Printf("received invalid reject [request=%v, peer=%v]", req, c)
1289 err = fmt.Errorf("received invalid reject [request=%v]", req)
1291 case pp.AllowedFast:
1292 torrent.Add("allowed fasts received", 1)
1293 log.Fmsg("peer allowed fast: %d", msg.Index).AddValues(c).LogLevel(log.Debug, c.t.logger)
1294 c.updateRequests("PeerConn.mainReadLoop allowed fast")
1296 err = c.onReadExtendedMsg(msg.ExtendedID, msg.ExtendedPayload)
1298 err = fmt.Errorf("received unknown message type: %#v", msg.Type)
1306 // Returns true if it was valid to reject the request.
1307 func (c *Peer) remoteRejectedRequest(r RequestIndex) bool {
1308 if c.deleteRequest(r) {
1310 } else if !c.requestState.Cancelled.CheckedRemove(r) {
1313 if c.isLowOnRequests() {
1314 c.updateRequests("Peer.remoteRejectedRequest")
1316 c.decExpectedChunkReceive(r)
1320 func (c *Peer) decExpectedChunkReceive(r RequestIndex) {
1321 count := c.validReceiveChunks[r]
1323 delete(c.validReceiveChunks, r)
1324 } else if count > 1 {
1325 c.validReceiveChunks[r] = count - 1
1331 func (c *PeerConn) onReadExtendedMsg(id pp.ExtensionNumber, payload []byte) (err error) {
1333 // TODO: Should we still do this?
1335 // These clients use their own extension IDs for outgoing message
1336 // types, which is incorrect.
1337 if bytes.HasPrefix(c.PeerID[:], []byte("-SD0100-")) || strings.HasPrefix(string(c.PeerID[:]), "-XL0012-") {
1345 case pp.HandshakeExtendedID:
1346 var d pp.ExtendedHandshakeMessage
1347 if err := bencode.Unmarshal(payload, &d); err != nil {
1348 c.logger.Printf("error parsing extended handshake message %q: %s", payload, err)
1349 return fmt.Errorf("unmarshalling extended handshake payload: %w", err)
1351 if cb := c.callbacks.ReadExtendedHandshake; cb != nil {
1354 // c.logger.WithDefaultLevel(log.Debug).Printf("received extended handshake message:\n%s", spew.Sdump(d))
1356 c.PeerMaxRequests = d.Reqq
1358 c.PeerClientName.Store(d.V)
1359 if c.PeerExtensionIDs == nil {
1360 c.PeerExtensionIDs = make(map[pp.ExtensionName]pp.ExtensionNumber, len(d.M))
1362 c.PeerListenPort = d.Port
1363 c.PeerPrefersEncryption = d.Encryption
1364 for name, id := range d.M {
1365 if _, ok := c.PeerExtensionIDs[name]; !ok {
1366 peersSupportingExtension.Add(
1367 // expvar.Var.String must produce valid JSON. "ut_payme\xeet_address" was being
1368 // entered here which caused problems later when unmarshalling.
1369 strconv.Quote(string(name)),
1372 c.PeerExtensionIDs[name] = id
1374 if d.MetadataSize != 0 {
1375 if err = t.setMetadataSize(d.MetadataSize); err != nil {
1376 return fmt.Errorf("setting metadata size to %d: %w", d.MetadataSize, err)
1379 c.requestPendingMetadata()
1380 if !t.cl.config.DisablePEX {
1381 t.pex.Add(c) // we learnt enough now
1385 case metadataExtendedId:
1386 err := cl.gotMetadataExtensionMsg(payload, t, c)
1388 return fmt.Errorf("handling metadata extension message: %w", err)
1392 if !c.pex.IsEnabled() {
1393 return nil // or hang-up maybe?
1395 return c.pex.Recv(payload)
1397 return fmt.Errorf("unexpected extended message ID: %v", id)
1401 // Set both the Reader and Writer for the connection from a single ReadWriter.
1402 func (cn *PeerConn) setRW(rw io.ReadWriter) {
1407 // Returns the Reader and Writer as a combined ReadWriter.
1408 func (cn *PeerConn) rw() io.ReadWriter {
1415 func (c *Peer) doChunkReadStats(size int64) {
1416 c.allStats(func(cs *ConnStats) { cs.receivedChunk(size) })
1419 // Handle a received chunk from a peer.
1420 func (c *Peer) receiveChunk(msg *pp.Message) error {
1421 chunksReceived.Add("total", 1)
1423 ppReq := newRequestFromMessage(msg)
1424 req := c.t.requestIndexFromRequest(ppReq)
1427 if c.bannableAddr.Ok {
1428 t.smartBanCache.RecordBlock(c.bannableAddr.Value, req, msg.Piece)
1432 chunksReceived.Add("while choked", 1)
1435 if c.validReceiveChunks[req] <= 0 {
1436 chunksReceived.Add("unexpected", 1)
1437 return errors.New("received unexpected chunk")
1439 c.decExpectedChunkReceive(req)
1441 if c.peerChoking && c.peerAllowedFast.Contains(pieceIndex(ppReq.Index)) {
1442 chunksReceived.Add("due to allowed fast", 1)
1445 // The request needs to be deleted immediately to prevent cancels occurring asynchronously when
1446 // have actually already received the piece, while we have the Client unlocked to write the data
1450 if c.requestState.Requests.Contains(req) {
1451 for _, f := range c.callbacks.ReceivedRequested {
1452 f(PeerMessageEvent{c, msg})
1455 // Request has been satisfied.
1456 if c.deleteRequest(req) || c.requestState.Cancelled.CheckedRemove(req) {
1459 c._chunksReceivedWhileExpecting++
1461 if c.isLowOnRequests() {
1462 c.updateRequests("Peer.receiveChunk deleted request")
1465 chunksReceived.Add("unintended", 1)
1471 // Do we actually want this chunk?
1472 if t.haveChunk(ppReq) {
1473 // panic(fmt.Sprintf("%+v", ppReq))
1474 chunksReceived.Add("redundant", 1)
1475 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadWasted }))
1479 piece := &t.pieces[ppReq.Index]
1481 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadUseful }))
1482 c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulData }))
1484 c.piecesReceivedSinceLastRequestUpdate++
1485 c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulIntendedData }))
1487 for _, f := range c.t.cl.config.Callbacks.ReceivedUsefulData {
1488 f(ReceivedUsefulDataEvent{c, msg})
1490 c.lastUsefulChunkReceived = time.Now()
1492 // Need to record that it hasn't been written yet, before we attempt to do
1493 // anything with it.
1494 piece.incrementPendingWrites()
1495 // Record that we have the chunk, so we aren't trying to download it while
1496 // waiting for it to be written to storage.
1497 piece.unpendChunkIndex(chunkIndexFromChunkSpec(ppReq.ChunkSpec, t.chunkSize))
1499 // Cancel pending requests for this chunk from *other* peers.
1500 if p := t.requestingPeer(req); p != nil {
1502 panic("should not be pending request from conn that just received it")
1507 err := func() error {
1510 concurrentChunkWrites.Add(1)
1511 defer concurrentChunkWrites.Add(-1)
1512 // Write the chunk out. Note that the upper bound on chunk writing concurrency will be the
1513 // number of connections. We write inline with receiving the chunk (with this lock dance),
1514 // because we want to handle errors synchronously and I haven't thought of a nice way to
1515 // defer any concurrency to the storage and have that notify the client of errors. TODO: Do
1517 return t.writeChunk(int(msg.Index), int64(msg.Begin), msg.Piece)
1520 piece.decrementPendingWrites()
1523 c.logger.WithDefaultLevel(log.Error).Printf("writing received chunk %v: %v", req, err)
1525 // Necessary to pass TestReceiveChunkStorageFailureSeederFastExtensionDisabled. I think a
1526 // request update runs while we're writing the chunk that just failed. Then we never do a
1527 // fresh update after pending the failed request.
1528 c.updateRequests("Peer.receiveChunk error writing chunk")
1529 t.onWriteChunkErr(err)
1533 c.onDirtiedPiece(pieceIndex(ppReq.Index))
1535 // We need to ensure the piece is only queued once, so only the last chunk writer gets this job.
1536 if t.pieceAllDirty(pieceIndex(ppReq.Index)) && piece.pendingWrites == 0 {
1537 t.queuePieceCheck(pieceIndex(ppReq.Index))
1538 // We don't pend all chunks here anymore because we don't want code dependent on the dirty
1539 // chunk status (such as the haveChunk call above) to have to check all the various other
1540 // piece states like queued for hash, hashing etc. This does mean that we need to be sure
1541 // that chunk pieces are pended at an appropriate time later however.
1544 cl.event.Broadcast()
1545 // We do this because we've written a chunk, and may change PieceState.Partial.
1546 t.publishPieceChange(pieceIndex(ppReq.Index))
1551 func (c *Peer) onDirtiedPiece(piece pieceIndex) {
1552 if c.peerTouchedPieces == nil {
1553 c.peerTouchedPieces = make(map[pieceIndex]struct{})
1555 c.peerTouchedPieces[piece] = struct{}{}
1556 ds := &c.t.pieces[piece].dirtiers
1558 *ds = make(map[*Peer]struct{})
1560 (*ds)[c] = struct{}{}
1563 func (c *PeerConn) uploadAllowed() bool {
1564 if c.t.cl.config.NoUpload {
1567 if c.t.dataUploadDisallowed {
1573 if !c.peerHasWantedPieces() {
1576 // Don't upload more than 100 KiB more than we download.
1577 if c._stats.BytesWrittenData.Int64() >= c._stats.BytesReadData.Int64()+100<<10 {
1583 func (c *PeerConn) setRetryUploadTimer(delay time.Duration) {
1584 if c.uploadTimer == nil {
1585 c.uploadTimer = time.AfterFunc(delay, c.tickleWriter)
1587 c.uploadTimer.Reset(delay)
1591 // Also handles choking and unchoking of the remote peer.
1592 func (c *PeerConn) upload(msg func(pp.Message) bool) bool {
1593 // Breaking or completing this loop means we don't want to upload to the
1594 // peer anymore, and we choke them.
1596 for c.uploadAllowed() {
1597 // We want to upload to the peer.
1598 if !c.unchoke(msg) {
1601 for r, state := range c.peerRequests {
1602 if state.data == nil {
1605 res := c.t.cl.config.UploadRateLimiter.ReserveN(time.Now(), int(r.Length))
1607 panic(fmt.Sprintf("upload rate limiter burst size < %d", r.Length))
1609 delay := res.Delay()
1612 c.setRetryUploadTimer(delay)
1613 // Hard to say what to return here.
1616 more := c.sendChunk(r, msg, state)
1617 delete(c.peerRequests, r)
1628 func (cn *PeerConn) drop() {
1629 cn.t.dropConnection(cn)
1632 func (cn *PeerConn) ban() {
1633 cn.t.cl.banPeerIP(cn.remoteIp())
1636 func (cn *Peer) netGoodPiecesDirtied() int64 {
1637 return cn._stats.PiecesDirtiedGood.Int64() - cn._stats.PiecesDirtiedBad.Int64()
1640 func (c *Peer) peerHasWantedPieces() bool {
1641 if all, _ := c.peerHasAllPieces(); all {
1642 return !c.t.haveAllPieces() && !c.t._pendingPieces.IsEmpty()
1644 if !c.t.haveInfo() {
1645 return !c.peerPieces().IsEmpty()
1647 return c.peerPieces().Intersects(&c.t._pendingPieces)
1650 // Returns true if an outstanding request is removed. Cancelled requests should be handled
1652 func (c *Peer) deleteRequest(r RequestIndex) bool {
1653 if !c.requestState.Requests.CheckedRemove(r) {
1656 for _, f := range c.callbacks.DeletedRequest {
1657 f(PeerRequestEvent{c, c.t.requestIndexToRequest(r)})
1659 c.updateExpectingChunks()
1660 if c.t.requestingPeer(r) != c {
1661 panic("only one peer should have a given request at a time")
1663 delete(c.t.requestState, r)
1664 // c.t.iterPeers(func(p *Peer) {
1665 // if p.isLowOnRequests() {
1666 // p.updateRequests("Peer.deleteRequest")
1672 func (c *Peer) deleteAllRequests(reason string) {
1673 if c.requestState.Requests.IsEmpty() {
1676 c.requestState.Requests.IterateSnapshot(func(x RequestIndex) bool {
1677 if !c.deleteRequest(x) {
1678 panic("request should exist")
1682 c.assertNoRequests()
1683 c.t.iterPeers(func(p *Peer) {
1684 if p.isLowOnRequests() {
1685 p.updateRequests(reason)
1691 func (c *Peer) assertNoRequests() {
1692 if !c.requestState.Requests.IsEmpty() {
1693 panic(c.requestState.Requests.GetCardinality())
1697 func (c *Peer) cancelAllRequests() {
1698 c.requestState.Requests.IterateSnapshot(func(x RequestIndex) bool {
1702 c.assertNoRequests()
1706 // This is called when something has changed that should wake the writer, such as putting stuff into
1707 // the writeBuffer, or changing some state that the writer can act on.
1708 func (c *PeerConn) tickleWriter() {
1709 c.messageWriter.writeCond.Broadcast()
1712 func (c *PeerConn) sendChunk(r Request, msg func(pp.Message) bool, state *peerRequestState) (more bool) {
1713 c.lastChunkSent = time.Now()
1714 return msg(pp.Message{
1722 func (c *PeerConn) setTorrent(t *Torrent) {
1724 panic("connection already associated with a torrent")
1727 c.logger.WithDefaultLevel(log.Debug).Printf("set torrent=%v", t)
1728 t.reconcileHandshakeStats(c)
1731 func (c *Peer) peerPriority() (peerPriority, error) {
1732 return bep40Priority(c.remoteIpPort(), c.t.cl.publicAddr(c.remoteIp()))
1735 func (c *Peer) remoteIp() net.IP {
1736 host, _, _ := net.SplitHostPort(c.RemoteAddr.String())
1737 return net.ParseIP(host)
1740 func (c *Peer) remoteIpPort() IpPort {
1741 ipa, _ := tryIpPortFromNetAddr(c.RemoteAddr)
1742 return IpPort{ipa.IP, uint16(ipa.Port)}
1745 func (c *PeerConn) pexPeerFlags() pp.PexPeerFlags {
1746 f := pp.PexPeerFlags(0)
1747 if c.PeerPrefersEncryption {
1748 f |= pp.PexPrefersEncryption
1751 f |= pp.PexOutgoingConn
1754 f |= pp.PexSupportsUtp
1759 // This returns the address to use if we want to dial the peer again. It incorporates the peer's
1760 // advertised listen port.
1761 func (c *PeerConn) dialAddr() PeerRemoteAddr {
1762 if !c.outgoing && c.PeerListenPort != 0 {
1763 switch addr := c.RemoteAddr.(type) {
1766 dialAddr.Port = c.PeerListenPort
1770 dialAddr.Port = c.PeerListenPort
1777 func (c *PeerConn) pexEvent(t pexEventType) pexEvent {
1778 f := c.pexPeerFlags()
1779 addr := c.dialAddr()
1780 return pexEvent{t, addr, f, nil}
1783 func (c *PeerConn) String() string {
1784 return fmt.Sprintf("%T %p [id=%q, exts=%v, v=%q]", c, c, c.PeerID, c.PeerExtensionBytes, c.PeerClientName.Load())
1787 func (c *Peer) trust() connectionTrust {
1788 return connectionTrust{c.trusted, c.netGoodPiecesDirtied()}
1791 type connectionTrust struct {
1793 NetGoodPiecesDirted int64
1796 func (l connectionTrust) Less(r connectionTrust) bool {
1797 return multiless.New().Bool(l.Implicit, r.Implicit).Int64(l.NetGoodPiecesDirted, r.NetGoodPiecesDirted).Less()
1800 // Returns the pieces the peer could have based on their claims. If we don't know how many pieces
1801 // are in the torrent, it could be a very large range the peer has sent HaveAll.
1802 func (cn *PeerConn) PeerPieces() *roaring.Bitmap {
1804 defer cn.locker().RUnlock()
1805 return cn.newPeerPieces()
1808 // Returns a new Bitmap that includes bits for all pieces the peer could have based on their claims.
1809 func (cn *Peer) newPeerPieces() *roaring.Bitmap {
1810 // TODO: Can we use copy on write?
1811 ret := cn.peerPieces().Clone()
1812 if all, _ := cn.peerHasAllPieces(); all {
1813 if cn.t.haveInfo() {
1814 ret.AddRange(0, bitmap.BitRange(cn.t.numPieces()))
1816 ret.AddRange(0, bitmap.ToEnd)
1822 func (cn *Peer) stats() *ConnStats {
1826 func (p *Peer) TryAsPeerConn() (*PeerConn, bool) {
1827 pc, ok := p.peerImpl.(*PeerConn)
1831 func (p *Peer) uncancelledRequests() uint64 {
1832 return p.requestState.Requests.GetCardinality()
1835 func (pc *PeerConn) remoteIsTransmission() bool {
1836 return bytes.HasPrefix(pc.PeerID[:], []byte("-TR")) && pc.PeerID[7] == '-'