17 "github.com/RoaringBitmap/roaring"
18 "github.com/anacrolix/log"
19 "github.com/anacrolix/missinggo/iter"
20 "github.com/anacrolix/missinggo/v2/bitmap"
21 "github.com/anacrolix/multiless"
23 "github.com/anacrolix/chansync"
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"
31 type PeerSource string
34 PeerSourceTracker = "Tr"
35 PeerSourceIncoming = "I"
36 PeerSourceDhtGetPeers = "Hg" // Peers we found by searching a DHT.
37 PeerSourceDhtAnnouncePeer = "Ha" // Peers that were announced to us by a DHT.
39 // The peer was given directly, such as through a magnet link.
40 PeerSourceDirect = "M"
43 type peerRequestState struct {
47 type PeerRemoteAddr interface {
51 // Since we have to store all the requests in memory, we can't reasonably exceed what would be
52 // indexable with the memory space available.
55 requestState = request_strategy.PeerRequestState
59 // First to ensure 64-bit alignment for atomics. See #262.
69 RemoteAddr PeerRemoteAddr
70 // True if the connection is operating over MSE obfuscation.
72 cryptoMethod mse.CryptoMethod
75 closed chansync.SetOnce
76 // Set true after we've added our ConnStats generated during handshake to
77 // other ConnStat instances as determined when the *Torrent became known.
78 reconciledHandshakeStats bool
80 lastMessageReceived time.Time
81 completedHandshake time.Time
82 lastUsefulChunkReceived time.Time
83 lastChunkSent time.Time
85 // Stuff controlled by the local peer.
86 needRequestUpdate string
87 requestState requestState
88 updateRequestsTimer *time.Timer
89 lastRequestUpdate time.Time
90 peakRequests maxRequests
91 lastBecameInterested time.Time
92 priorInterest time.Duration
94 lastStartedExpectingToReceiveChunks time.Time
95 cumulativeExpectedToReceiveChunks time.Duration
96 _chunksReceivedWhileExpecting int64
99 piecesReceivedSinceLastRequestUpdate maxRequests
100 maxPiecesReceivedBetweenRequestUpdates maxRequests
101 // Chunks that we might reasonably expect to receive from the peer. Due to latency, buffering,
102 // and implementation differences, we may receive chunks that are no longer in the set of
103 // requests actually want. This could use a roaring.BSI if the memory use becomes noticeable.
104 validReceiveChunks map[RequestIndex]int
105 // Indexed by metadata piece, set to true if posted and pending a
107 metadataRequests []bool
108 sentHaves bitmap.Bitmap
110 // Stuff controlled by the remote peer.
113 peerRequests map[Request]*peerRequestState
114 PeerPrefersEncryption bool // as indicated by 'e' field in extension handshake
116 // The highest possible number of pieces the torrent could have based on
117 // communication with the peer. Generally only useful until we have the
119 peerMinPieces pieceIndex
120 // Pieces we've accepted chunks for from the peer.
121 peerTouchedPieces map[pieceIndex]struct{}
122 peerAllowedFast roaring.Bitmap
124 PeerMaxRequests maxRequests // Maximum pending requests the peer allows.
125 PeerExtensionIDs map[pp.ExtensionName]pp.ExtensionNumber
126 PeerClientName atomic.Value
131 // Maintains the state of a BitTorrent-protocol based connection with a peer.
132 type PeerConn struct {
135 // A string that should identify the PeerConn's net.Conn endpoints. The net.Conn could
136 // be wrapping WebRTC, uTP, or TCP etc. Used in writing the conn status for peers.
141 PeerExtensionBytes pp.PeerExtensionBits
143 // The actual Conn, used for closing, and setting socket options. Do not use methods on this
144 // while holding any mutexes.
146 // The Reader and Writer for this Conn, with hooks installed for stats,
147 // limiting, deadlines etc.
151 messageWriter peerConnMsgWriter
153 uploadTimer *time.Timer
156 // The pieces the peer has claimed to have.
157 _peerPieces roaring.Bitmap
158 // The peer has everything. This can occur due to a special message, when
159 // we may not even know the number of pieces in the torrent yet.
163 func (cn *PeerConn) connStatusString() string {
164 return fmt.Sprintf("%+-55q %s %s", cn.PeerID, cn.PeerExtensionBytes, cn.connString)
167 func (cn *Peer) updateExpectingChunks() {
168 if cn.expectingChunks() {
169 if cn.lastStartedExpectingToReceiveChunks.IsZero() {
170 cn.lastStartedExpectingToReceiveChunks = time.Now()
173 if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
174 cn.cumulativeExpectedToReceiveChunks += time.Since(cn.lastStartedExpectingToReceiveChunks)
175 cn.lastStartedExpectingToReceiveChunks = time.Time{}
180 func (cn *Peer) expectingChunks() bool {
181 if cn.requestState.Requests.IsEmpty() {
184 if !cn.requestState.Interested {
190 haveAllowedFastRequests := false
191 cn.peerAllowedFast.Iterate(func(i uint32) bool {
192 haveAllowedFastRequests = roaringBitmapRangeCardinality(
193 &cn.requestState.Requests,
194 cn.t.pieceRequestIndexOffset(pieceIndex(i)),
195 cn.t.pieceRequestIndexOffset(pieceIndex(i+1)),
197 return !haveAllowedFastRequests
199 return haveAllowedFastRequests
202 func (cn *Peer) remoteChokingPiece(piece pieceIndex) bool {
203 return cn.peerChoking && !cn.peerAllowedFast.Contains(bitmap.BitIndex(piece))
206 // Returns true if the connection is over IPv6.
207 func (cn *PeerConn) ipv6() bool {
212 return len(ip) == net.IPv6len
215 // Returns true the if the dialer/initiator has the lower client peer ID. TODO: Find the
216 // specification for this.
217 func (cn *PeerConn) isPreferredDirection() bool {
218 return bytes.Compare(cn.t.cl.peerID[:], cn.PeerID[:]) < 0 == cn.outgoing
221 // Returns whether the left connection should be preferred over the right one,
222 // considering only their networking properties. If ok is false, we can't
224 func (l *PeerConn) hasPreferredNetworkOver(r *PeerConn) bool {
226 ml.NextBool(l.isPreferredDirection(), r.isPreferredDirection())
227 ml.NextBool(!l.utp(), !r.utp())
228 ml.NextBool(l.ipv6(), r.ipv6())
232 func (cn *Peer) cumInterest() time.Duration {
233 ret := cn.priorInterest
234 if cn.requestState.Interested {
235 ret += time.Since(cn.lastBecameInterested)
240 func (cn *PeerConn) peerHasAllPieces() (all, known bool) {
241 if cn.peerSentHaveAll {
244 if !cn.t.haveInfo() {
247 return cn._peerPieces.GetCardinality() == uint64(cn.t.numPieces()), true
250 func (cn *Peer) locker() *lockWithDeferreds {
251 return cn.t.cl.locker()
254 func (cn *Peer) supportsExtension(ext pp.ExtensionName) bool {
255 _, ok := cn.PeerExtensionIDs[ext]
259 // The best guess at number of pieces in the torrent for this peer.
260 func (cn *Peer) bestPeerNumPieces() pieceIndex {
262 return cn.t.numPieces()
264 return cn.peerMinPieces
267 func (cn *Peer) completedString() string {
268 have := pieceIndex(cn.peerPieces().GetCardinality())
269 if all, _ := cn.peerHasAllPieces(); all {
270 have = cn.bestPeerNumPieces()
272 return fmt.Sprintf("%d/%d", have, cn.bestPeerNumPieces())
275 func (cn *PeerConn) onGotInfo(info *metainfo.Info) {
276 cn.setNumPieces(info.NumPieces())
279 // Correct the PeerPieces slice length. Return false if the existing slice is invalid, such as by
280 // receiving badly sized BITFIELD, or invalid HAVE messages.
281 func (cn *PeerConn) setNumPieces(num pieceIndex) {
282 cn._peerPieces.RemoveRange(bitmap.BitRange(num), bitmap.ToEnd)
283 cn.peerPiecesChanged()
286 func (cn *PeerConn) peerPieces() *roaring.Bitmap {
287 return &cn._peerPieces
290 func eventAgeString(t time.Time) string {
294 return fmt.Sprintf("%.2fs ago", time.Since(t).Seconds())
297 func (cn *PeerConn) connectionFlags() (ret string) {
299 ret += string([]byte{b})
301 if cn.cryptoMethod == mse.CryptoMethodRC4 {
303 } else if cn.headerEncrypted {
306 ret += string(cn.Discovery)
313 func (cn *PeerConn) utp() bool {
314 return parseNetworkString(cn.Network).Udp
317 // Inspired by https://github.com/transmission/transmission/wiki/Peer-Status-Text.
318 func (cn *Peer) statusFlags() (ret string) {
320 ret += string([]byte{b})
322 if cn.requestState.Interested {
329 ret += cn.connectionFlags()
331 if cn.peerInterested {
340 func (cn *Peer) downloadRate() float64 {
341 num := cn._stats.BytesReadUsefulData.Int64()
345 return float64(num) / cn.totalExpectingTime().Seconds()
348 func (cn *Peer) numRequestsByPiece() (ret map[pieceIndex]int) {
349 ret = make(map[pieceIndex]int)
350 cn.requestState.Requests.Iterate(func(x uint32) bool {
351 ret[pieceIndex(x/cn.t.chunksPerRegularPiece())]++
357 func (cn *Peer) writeStatus(w io.Writer, t *Torrent) {
358 // \t isn't preserved in <pre> blocks?
359 if cn.closed.IsSet() {
360 fmt.Fprint(w, "CLOSED: ")
362 fmt.Fprintln(w, cn.connStatusString())
363 prio, err := cn.peerPriority()
364 prioStr := fmt.Sprintf("%08x", prio)
366 prioStr += ": " + err.Error()
368 fmt.Fprintf(w, " bep40-prio: %v\n", prioStr)
369 fmt.Fprintf(w, " last msg: %s, connected: %s, last helpful: %s, itime: %s, etime: %s\n",
370 eventAgeString(cn.lastMessageReceived),
371 eventAgeString(cn.completedHandshake),
372 eventAgeString(cn.lastHelpful()),
374 cn.totalExpectingTime(),
377 " %s completed, %d pieces touched, good chunks: %v/%v:%v reqq: %d+%v/(%d/%d):%d/%d, flags: %s, dr: %.1f KiB/s\n",
378 cn.completedString(),
379 len(cn.peerTouchedPieces),
380 &cn._stats.ChunksReadUseful,
381 &cn._stats.ChunksRead,
382 &cn._stats.ChunksWritten,
383 cn.requestState.Requests.GetCardinality(),
384 cn.requestState.Cancelled.GetCardinality(),
385 cn.nominalMaxRequests(),
387 len(cn.peerRequests),
390 cn.downloadRate()/(1<<10),
392 fmt.Fprintf(w, " requested pieces:")
393 type pieceNumRequestsType struct {
397 var pieceNumRequests []pieceNumRequestsType
398 for piece, count := range cn.numRequestsByPiece() {
399 pieceNumRequests = append(pieceNumRequests, pieceNumRequestsType{piece, count})
401 sort.Slice(pieceNumRequests, func(i, j int) bool {
402 return pieceNumRequests[i].piece < pieceNumRequests[j].piece
404 for _, elem := range pieceNumRequests {
405 fmt.Fprintf(w, " %v(%v)", elem.piece, elem.numRequests)
410 func (p *Peer) close() {
414 if p.updateRequestsTimer != nil {
415 p.updateRequestsTimer.Stop()
419 p.t.decPeerPieceAvailability(p)
421 for _, f := range p.callbacks.PeerClosed {
426 func (cn *PeerConn) onClose() {
427 if cn.pex.IsEnabled() {
434 if cb := cn.callbacks.PeerConnClosed; cb != nil {
439 // Peer definitely has a piece, for purposes of requesting. So it's not sufficient that we think
440 // they do (known=true).
441 func (cn *Peer) peerHasPiece(piece pieceIndex) bool {
442 if all, known := cn.peerHasAllPieces(); all && known {
445 return cn.peerPieces().ContainsInt(piece)
448 // 64KiB, but temporarily less to work around an issue with WebRTC. TODO: Update when
449 // https://github.com/pion/datachannel/issues/59 is fixed.
451 writeBufferHighWaterLen = 1 << 15
452 writeBufferLowWaterLen = writeBufferHighWaterLen / 2
455 // Writes a message into the write buffer. Returns whether it's okay to keep writing. Writing is
456 // done asynchronously, so it may be that we're not able to honour backpressure from this method.
457 func (cn *PeerConn) write(msg pp.Message) bool {
458 torrent.Add(fmt.Sprintf("messages written of type %s", msg.Type.String()), 1)
459 // We don't need to track bytes here because the connection's Writer has that behaviour injected
460 // (although there's some delay between us buffering the message, and the connection writer
461 // flushing it out.).
462 notFull := cn.messageWriter.write(msg)
463 // Last I checked only Piece messages affect stats, and we don't write those.
469 func (cn *PeerConn) requestMetadataPiece(index int) {
470 eID := cn.PeerExtensionIDs[pp.ExtensionNameMetadata]
471 if eID == pp.ExtensionDeleteNumber {
474 if index < len(cn.metadataRequests) && cn.metadataRequests[index] {
477 cn.logger.WithDefaultLevel(log.Debug).Printf("requesting metadata piece %d", index)
478 cn.write(pp.MetadataExtensionRequestMsg(eID, index))
479 for index >= len(cn.metadataRequests) {
480 cn.metadataRequests = append(cn.metadataRequests, false)
482 cn.metadataRequests[index] = true
485 func (cn *PeerConn) requestedMetadataPiece(index int) bool {
486 return index < len(cn.metadataRequests) && cn.metadataRequests[index]
490 interestedMsgLen = len(pp.Message{Type: pp.Interested}.MustMarshalBinary())
491 requestMsgLen = len(pp.Message{Type: pp.Request}.MustMarshalBinary())
492 // This is the maximum request count that could fit in the write buffer if it's at or below the
493 // low water mark when we run maybeUpdateActualRequestState.
494 maxLocalToRemoteRequests = (writeBufferHighWaterLen - writeBufferLowWaterLen - interestedMsgLen) / requestMsgLen
497 // The actual value to use as the maximum outbound requests.
498 func (cn *Peer) nominalMaxRequests() maxRequests {
499 return maxRequests(maxInt(1, minInt(cn.PeerMaxRequests, cn.peakRequests*2, maxLocalToRemoteRequests)))
502 func (cn *Peer) totalExpectingTime() (ret time.Duration) {
503 ret = cn.cumulativeExpectedToReceiveChunks
504 if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
505 ret += time.Since(cn.lastStartedExpectingToReceiveChunks)
510 func (cn *PeerConn) onPeerSentCancel(r Request) {
511 if _, ok := cn.peerRequests[r]; !ok {
512 torrent.Add("unexpected cancels received", 1)
515 if cn.fastEnabled() {
518 delete(cn.peerRequests, r)
522 func (cn *PeerConn) choke(msg messageWriter) (more bool) {
527 more = msg(pp.Message{
530 if !cn.fastEnabled() {
531 cn.peerRequests = nil
536 func (cn *PeerConn) unchoke(msg func(pp.Message) bool) bool {
541 return msg(pp.Message{
546 func (cn *Peer) setInterested(interested bool) bool {
547 if cn.requestState.Interested == interested {
550 cn.requestState.Interested = interested
552 cn.lastBecameInterested = time.Now()
553 } else if !cn.lastBecameInterested.IsZero() {
554 cn.priorInterest += time.Since(cn.lastBecameInterested)
556 cn.updateExpectingChunks()
557 // log.Printf("%p: setting interest: %v", cn, interested)
558 return cn.writeInterested(interested)
561 func (pc *PeerConn) writeInterested(interested bool) bool {
562 return pc.write(pp.Message{
563 Type: func() pp.MessageType {
567 return pp.NotInterested
573 // The function takes a message to be sent, and returns true if more messages
575 type messageWriter func(pp.Message) bool
577 // This function seems to only used by Peer.request. It's all logic checks, so maybe we can no-op it
578 // when we want to go fast.
579 func (cn *Peer) shouldRequest(r RequestIndex) error {
580 pi := pieceIndex(r / cn.t.chunksPerRegularPiece())
581 if cn.requestState.Cancelled.Contains(r) {
582 return errors.New("request is cancelled and waiting acknowledgement")
584 if !cn.peerHasPiece(pi) {
585 return errors.New("requesting piece peer doesn't have")
587 if !cn.t.peerIsActive(cn) {
588 panic("requesting but not in active conns")
590 if cn.closed.IsSet() {
591 panic("requesting when connection is closed")
593 if cn.t.hashingPiece(pi) {
594 panic("piece is being hashed")
596 if cn.t.pieceQueuedForHash(pi) {
597 panic("piece is queued for hash")
599 if cn.peerChoking && !cn.peerAllowedFast.Contains(bitmap.BitIndex(pi)) {
600 // This could occur if we made a request with the fast extension, and then got choked and
601 // haven't had the request rejected yet.
602 if !cn.requestState.Requests.Contains(r) {
603 panic("peer choking and piece not allowed fast")
609 func (cn *Peer) mustRequest(r RequestIndex) bool {
610 more, err := cn.request(r)
617 func (cn *Peer) request(r RequestIndex) (more bool, err error) {
618 if err := cn.shouldRequest(r); err != nil {
621 if cn.requestState.Requests.Contains(r) {
624 if maxRequests(cn.requestState.Requests.GetCardinality()) >= cn.nominalMaxRequests() {
625 return true, errors.New("too many outstanding requests")
627 cn.requestState.Requests.Add(r)
628 if cn.validReceiveChunks == nil {
629 cn.validReceiveChunks = make(map[RequestIndex]int)
631 cn.validReceiveChunks[r]++
632 cn.t.pendingRequests[r] = cn
633 cn.t.lastRequested[r] = time.Now()
634 cn.updateExpectingChunks()
635 ppReq := cn.t.requestIndexToRequest(r)
636 for _, f := range cn.callbacks.SentRequest {
637 f(PeerRequestEvent{cn, ppReq})
639 return cn.peerImpl._request(ppReq), nil
642 func (me *PeerConn) _request(r Request) bool {
643 return me.write(pp.Message{
651 func (me *Peer) cancel(r RequestIndex) {
652 if !me.deleteRequest(r) {
653 panic("request not existing should have been guarded")
656 if !me.requestState.Cancelled.CheckedAdd(r) {
657 panic("request already cancelled")
661 if me.isLowOnRequests() {
662 me.updateRequests("Peer.cancel")
666 func (me *PeerConn) _cancel(r RequestIndex) bool {
667 me.write(makeCancelMessage(me.t.requestIndexToRequest(r)))
668 // Transmission does not send rejects for received cancels. See
669 // https://github.com/transmission/transmission/pull/2275.
670 return me.fastEnabled() && !me.remoteIsTransmission()
673 func (cn *PeerConn) fillWriteBuffer() {
674 if cn.messageWriter.writeBuffer.Len() > writeBufferLowWaterLen {
675 // Fully committing to our max requests requires sufficient space (see
676 // maxLocalToRemoteRequests). Flush what we have instead. We also prefer always to make
677 // requests than to do PEX or upload, so we short-circuit before handling those. Any update
678 // request reason will not be cleared, so we'll come right back here when there's space. We
679 // can't do this in maybeUpdateActualRequestState because it's a method on Peer and has no
680 // knowledge of write buffers.
682 cn.maybeUpdateActualRequestState()
683 if cn.pex.IsEnabled() {
684 if flow := cn.pex.Share(cn.write); !flow {
691 func (cn *PeerConn) have(piece pieceIndex) {
692 if cn.sentHaves.Get(bitmap.BitIndex(piece)) {
697 Index: pp.Integer(piece),
699 cn.sentHaves.Add(bitmap.BitIndex(piece))
702 func (cn *PeerConn) postBitfield() {
703 if cn.sentHaves.Len() != 0 {
704 panic("bitfield must be first have-related message sent")
706 if !cn.t.haveAnyPieces() {
711 Bitfield: cn.t.bitfield(),
713 cn.sentHaves = bitmap.Bitmap{cn.t._completedPieces.Clone()}
716 // Sets a reason to update requests, and if there wasn't already one, handle it.
717 func (cn *Peer) updateRequests(reason string) {
718 if cn.needRequestUpdate != "" {
721 if reason != peerUpdateRequestsTimerReason && !cn.isLowOnRequests() {
724 cn.needRequestUpdate = reason
725 cn.handleUpdateRequests()
728 func (cn *PeerConn) handleUpdateRequests() {
729 // The writer determines the request state as needed when it can write.
733 // Emits the indices in the Bitmaps bms in order, never repeating any index.
734 // skip is mutated during execution, and its initial values will never be
736 func iterBitmapsDistinct(skip *bitmap.Bitmap, bms ...bitmap.Bitmap) iter.Func {
737 return func(cb iter.Callback) {
738 for _, bm := range bms {
740 func(_i interface{}) bool {
742 if skip.Contains(bitmap.BitIndex(i)) {
745 skip.Add(bitmap.BitIndex(i))
756 func (cn *Peer) peerPiecesChanged() {
757 cn.t.maybeDropMutuallyCompletePeer(cn)
760 func (cn *PeerConn) raisePeerMinPieces(newMin pieceIndex) {
761 if newMin > cn.peerMinPieces {
762 cn.peerMinPieces = newMin
766 func (cn *PeerConn) peerSentHave(piece pieceIndex) error {
767 if cn.t.haveInfo() && piece >= cn.t.numPieces() || piece < 0 {
768 return errors.New("invalid piece")
770 if cn.peerHasPiece(piece) {
773 cn.raisePeerMinPieces(piece + 1)
774 if !cn.peerHasPiece(piece) {
775 cn.t.incPieceAvailability(piece)
777 cn._peerPieces.Add(uint32(piece))
778 if cn.t.wantPieceIndex(piece) {
779 cn.updateRequests("have")
781 cn.peerPiecesChanged()
785 func (cn *PeerConn) peerSentBitfield(bf []bool) error {
787 panic("expected bitfield length divisible by 8")
789 // We know that the last byte means that at most the last 7 bits are wasted.
790 cn.raisePeerMinPieces(pieceIndex(len(bf) - 7))
791 if cn.t.haveInfo() && len(bf) > int(cn.t.numPieces()) {
792 // Ignore known excess pieces.
793 bf = bf[:cn.t.numPieces()]
795 bm := boolSliceToBitmap(bf)
796 if cn.t.haveInfo() && pieceIndex(bm.GetCardinality()) == cn.t.numPieces() {
797 cn.onPeerHasAllPieces()
801 cn.raisePeerMinPieces(pieceIndex(bm.Maximum()) + 1)
803 shouldUpdateRequests := false
804 if cn.peerSentHaveAll {
805 if !cn.t.deleteConnWithAllPieces(&cn.Peer) {
808 cn.peerSentHaveAll = false
809 if !cn._peerPieces.IsEmpty() {
810 panic("if peer has all, we expect no individual peer pieces to be set")
813 bm.Xor(&cn._peerPieces)
815 cn.peerSentHaveAll = false
816 // bm is now 'on' for pieces that are changing
817 bm.Iterate(func(x uint32) bool {
819 if cn._peerPieces.Contains(x) {
820 // Then we must be losing this piece
821 cn.t.decPieceAvailability(pi)
823 if !shouldUpdateRequests && cn.t.wantPieceIndex(pieceIndex(x)) {
824 shouldUpdateRequests = true
826 // We must be gaining this piece
827 cn.t.incPieceAvailability(pieceIndex(x))
831 // Apply the changes. If we had everything previously, this should be empty, so xor is the same
833 cn._peerPieces.Xor(&bm)
834 if shouldUpdateRequests {
835 cn.updateRequests("bitfield")
837 // We didn't guard this before, I see no reason to do it now.
838 cn.peerPiecesChanged()
842 func (cn *PeerConn) onPeerHasAllPieces() {
845 cn._peerPieces.Iterate(func(x uint32) bool {
846 t.decPieceAvailability(pieceIndex(x))
850 t.addConnWithAllPieces(&cn.Peer)
851 cn.peerSentHaveAll = true
852 cn._peerPieces.Clear()
853 if !cn.t._pendingPieces.IsEmpty() {
854 cn.updateRequests("Peer.onPeerHasAllPieces")
856 cn.peerPiecesChanged()
859 func (cn *PeerConn) onPeerSentHaveAll() error {
860 cn.onPeerHasAllPieces()
864 func (cn *PeerConn) peerSentHaveNone() error {
865 if cn.peerSentHaveAll {
866 cn.t.decPeerPieceAvailability(&cn.Peer)
868 cn._peerPieces.Clear()
869 cn.peerSentHaveAll = false
870 cn.peerPiecesChanged()
874 func (c *PeerConn) requestPendingMetadata() {
878 if c.PeerExtensionIDs[pp.ExtensionNameMetadata] == 0 {
879 // Peer doesn't support this.
882 // Request metadata pieces that we don't have in a random order.
884 for index := 0; index < c.t.metadataPieceCount(); index++ {
885 if !c.t.haveMetadataPiece(index) && !c.requestedMetadataPiece(index) {
886 pending = append(pending, index)
889 rand.Shuffle(len(pending), func(i, j int) { pending[i], pending[j] = pending[j], pending[i] })
890 for _, i := range pending {
891 c.requestMetadataPiece(i)
895 func (cn *PeerConn) wroteMsg(msg *pp.Message) {
896 torrent.Add(fmt.Sprintf("messages written of type %s", msg.Type.String()), 1)
897 if msg.Type == pp.Extended {
898 for name, id := range cn.PeerExtensionIDs {
899 if id != msg.ExtendedID {
902 torrent.Add(fmt.Sprintf("Extended messages written for protocol %q", name), 1)
905 cn.allStats(func(cs *ConnStats) { cs.wroteMsg(msg) })
908 // After handshake, we know what Torrent and Client stats to include for a
910 func (cn *Peer) postHandshakeStats(f func(*ConnStats)) {
916 // All ConnStats that include this connection. Some objects are not known
917 // until the handshake is complete, after which it's expected to reconcile the
919 func (cn *Peer) allStats(f func(*ConnStats)) {
921 if cn.reconciledHandshakeStats {
922 cn.postHandshakeStats(f)
926 func (cn *PeerConn) wroteBytes(n int64) {
927 cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesWritten }))
930 func (cn *Peer) readBytes(n int64) {
931 cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesRead }))
934 // Returns whether the connection could be useful to us. We're seeding and
935 // they want data, we don't have metainfo and they can provide it, etc.
936 func (c *Peer) useful() bool {
938 if c.closed.IsSet() {
942 return c.supportsExtension("ut_metadata")
944 if t.seeding() && c.peerInterested {
947 if c.peerHasWantedPieces() {
953 func (c *Peer) lastHelpful() (ret time.Time) {
954 ret = c.lastUsefulChunkReceived
955 if c.t.seeding() && c.lastChunkSent.After(ret) {
956 ret = c.lastChunkSent
961 func (c *PeerConn) fastEnabled() bool {
962 return c.PeerExtensionBytes.SupportsFast() && c.t.cl.config.Extensions.SupportsFast()
965 func (c *PeerConn) reject(r Request) {
966 if !c.fastEnabled() {
967 panic("fast not enabled")
969 c.write(r.ToMsg(pp.Reject))
970 delete(c.peerRequests, r)
973 func (c *PeerConn) onReadRequest(r Request) error {
974 requestedChunkLengths.Add(strconv.FormatUint(r.Length.Uint64(), 10), 1)
975 if _, ok := c.peerRequests[r]; ok {
976 torrent.Add("duplicate requests received", 1)
980 torrent.Add("requests received while choking", 1)
982 torrent.Add("requests rejected while choking", 1)
987 // TODO: What if they've already requested this?
988 if len(c.peerRequests) >= localClientReqq {
989 torrent.Add("requests received while queue full", 1)
993 // BEP 6 says we may close here if we choose.
996 if !c.t.havePiece(pieceIndex(r.Index)) {
997 // This isn't necessarily them screwing up. We can drop pieces
998 // from our storage, and can't communicate this to peers
999 // except by reconnecting.
1000 requestsReceivedForMissingPieces.Add(1)
1001 return fmt.Errorf("peer requested piece we don't have: %v", r.Index.Int())
1003 // Check this after we know we have the piece, so that the piece length will be known.
1004 if r.Begin+r.Length > c.t.pieceLength(pieceIndex(r.Index)) {
1005 torrent.Add("bad requests received", 1)
1006 return errors.New("bad Request")
1008 if c.peerRequests == nil {
1009 c.peerRequests = make(map[Request]*peerRequestState, localClientReqq)
1011 value := &peerRequestState{}
1012 c.peerRequests[r] = value
1013 go c.peerRequestDataReader(r, value)
1017 func (c *PeerConn) peerRequestDataReader(r Request, prs *peerRequestState) {
1018 b, err := readPeerRequestData(r, c)
1020 defer c.locker().Unlock()
1022 c.peerRequestDataReadFailed(err, r)
1025 panic("data must be non-nil to trigger send")
1027 torrent.Add("peer request data read successes", 1)
1033 // If this is maintained correctly, we might be able to support optional synchronous reading for
1034 // chunk sending, the way it used to work.
1035 func (c *PeerConn) peerRequestDataReadFailed(err error, r Request) {
1036 torrent.Add("peer request data read failures", 1)
1037 logLevel := log.Warning
1038 if c.t.hasStorageCap() {
1039 // It's expected that pieces might drop. See
1040 // https://github.com/anacrolix/torrent/issues/702#issuecomment-1000953313.
1041 logLevel = log.Debug
1043 c.logger.WithDefaultLevel(logLevel).Printf("error reading chunk for peer Request %v: %v", r, err)
1044 if c.t.closed.IsSet() {
1047 i := pieceIndex(r.Index)
1048 if c.t.pieceComplete(i) {
1049 // There used to be more code here that just duplicated the following break. Piece
1050 // completions are currently cached, so I'm not sure how helpful this update is, except to
1051 // pull any completion changes pushed to the storage backend in failed reads that got us
1053 c.t.updatePieceCompletion(i)
1055 // We've probably dropped a piece from storage, but there's no way to communicate this to the
1056 // peer. If they ask for it again, we kick them allowing us to send them updated piece states if
1057 // we reconnect. TODO: Instead, we could just try to update them with Bitfield or HaveNone and
1058 // if they kick us for breaking protocol, on reconnect we will be compliant again (at least
1060 if c.fastEnabled() {
1064 // If fast isn't enabled, I think we would have wiped all peer requests when we last
1065 // choked, and requests while we're choking would be ignored. It could be possible that
1066 // a peer request data read completed concurrently to it being deleted elsewhere.
1067 c.logger.WithDefaultLevel(log.Warning).Printf("already choking peer, requests might not be rejected correctly")
1069 // Choking a non-fast peer should cause them to flush all their requests.
1074 func readPeerRequestData(r Request, c *PeerConn) ([]byte, error) {
1075 b := make([]byte, r.Length)
1076 p := c.t.info.Piece(int(r.Index))
1077 n, err := c.t.readAt(b, p.Offset()+int64(r.Begin))
1084 panic("expected error")
1090 func runSafeExtraneous(f func()) {
1098 func (c *PeerConn) logProtocolBehaviour(level log.Level, format string, arg ...interface{}) {
1099 c.logger.WithLevel(level).WithContextText(fmt.Sprintf(
1100 "peer id %q, ext v %q", c.PeerID, c.PeerClientName.Load(),
1101 )).SkipCallers(1).Printf(format, arg...)
1104 // Processes incoming BitTorrent wire-protocol messages. The client lock is held upon entry and
1105 // exit. Returning will end the connection.
1106 func (c *PeerConn) mainReadLoop() (err error) {
1109 torrent.Add("connection.mainReadLoop returned with error", 1)
1111 torrent.Add("connection.mainReadLoop returned with no error", 1)
1117 decoder := pp.Decoder{
1118 R: bufio.NewReaderSize(c.r, 1<<17),
1119 MaxLength: 256 * 1024,
1127 err = decoder.Decode(&msg)
1129 if cb := c.callbacks.ReadMessage; cb != nil && err == nil {
1132 if t.closed.IsSet() || c.closed.IsSet() {
1138 c.lastMessageReceived = time.Now()
1140 receivedKeepalives.Add(1)
1143 messageTypesReceived.Add(msg.Type.String(), 1)
1144 if msg.Type.FastExtension() && !c.fastEnabled() {
1145 runSafeExtraneous(func() { torrent.Add("fast messages received when extension is disabled", 1) })
1146 return fmt.Errorf("received fast extension message (type=%v) but extension is disabled", msg.Type)
1153 if !c.fastEnabled() {
1154 if !c.deleteAllRequests().IsEmpty() {
1155 c.t.iterPeers(func(p *Peer) {
1156 if p.isLowOnRequests() {
1157 p.updateRequests("choked by non-fast PeerConn")
1162 // We don't decrement pending requests here, let's wait for the peer to either
1163 // reject or satisfy the outstanding requests. Additionally, some peers may unchoke
1164 // us and resume where they left off, we don't want to have piled on to those chunks
1165 // in the meanwhile. I think a peer's ability to abuse this should be limited: they
1166 // could let us request a lot of stuff, then choke us and never reject, but they're
1167 // only a single peer, our chunk balancing should smooth over this abuse.
1169 c.peerChoking = true
1170 c.updateExpectingChunks()
1173 // Some clients do this for some reason. Transmission doesn't error on this, so we
1174 // won't for consistency.
1175 c.logProtocolBehaviour(log.Debug, "received unchoke when already unchoked")
1178 c.peerChoking = false
1180 c.requestState.Requests.Iterate(func(x uint32) bool {
1181 if !c.peerAllowedFast.Contains(x / c.t.chunksPerRegularPiece()) {
1186 if preservedCount != 0 {
1187 // TODO: Yes this is a debug log but I'm not happy with the state of the logging lib
1189 c.logger.WithLevel(log.Debug).Printf(
1190 "%v requests were preserved while being choked (fast=%v)",
1193 torrent.Add("requestsPreservedThroughChoking", int64(preservedCount))
1195 if !c.t._pendingPieces.IsEmpty() {
1196 c.updateRequests("unchoked")
1198 c.updateExpectingChunks()
1200 c.peerInterested = true
1202 case pp.NotInterested:
1203 c.peerInterested = false
1204 // We don't clear their requests since it isn't clear in the spec.
1205 // We'll probably choke them for this, which will clear them if
1206 // appropriate, and is clearly specified.
1208 err = c.peerSentHave(pieceIndex(msg.Index))
1210 err = c.peerSentBitfield(msg.Bitfield)
1212 r := newRequestFromMessage(&msg)
1213 err = c.onReadRequest(r)
1215 c.doChunkReadStats(int64(len(msg.Piece)))
1216 err = c.receiveChunk(&msg)
1217 if len(msg.Piece) == int(t.chunkSize) {
1218 t.chunkPool.Put(&msg.Piece)
1221 err = fmt.Errorf("receiving chunk: %w", err)
1224 req := newRequestFromMessage(&msg)
1225 c.onPeerSentCancel(req)
1227 ipa, ok := tryIpPortFromNetAddr(c.RemoteAddr)
1231 pingAddr := net.UDPAddr{
1236 pingAddr.Port = int(msg.Port)
1238 cl.eachDhtServer(func(s DhtServer) {
1239 go s.Ping(&pingAddr)
1242 torrent.Add("suggests received", 1)
1243 log.Fmsg("peer suggested piece %d", msg.Index).AddValues(c, msg.Index).SetLevel(log.Debug).Log(c.t.logger)
1244 c.updateRequests("suggested")
1246 err = c.onPeerSentHaveAll()
1248 err = c.peerSentHaveNone()
1250 req := newRequestFromMessage(&msg)
1251 if !c.remoteRejectedRequest(c.t.requestIndexFromRequest(req)) {
1252 log.Printf("received invalid reject [request=%v, peer=%v]", req, c)
1253 err = fmt.Errorf("received invalid reject [request=%v]", req)
1255 case pp.AllowedFast:
1256 torrent.Add("allowed fasts received", 1)
1257 log.Fmsg("peer allowed fast: %d", msg.Index).AddValues(c).SetLevel(log.Debug).Log(c.t.logger)
1258 c.updateRequests("PeerConn.mainReadLoop allowed fast")
1260 err = c.onReadExtendedMsg(msg.ExtendedID, msg.ExtendedPayload)
1262 err = fmt.Errorf("received unknown message type: %#v", msg.Type)
1270 // Returns true if it was valid to reject the request.
1271 func (c *Peer) remoteRejectedRequest(r RequestIndex) bool {
1272 if c.deleteRequest(r) {
1274 } else if !c.requestState.Cancelled.CheckedRemove(r) {
1277 if c.isLowOnRequests() {
1278 c.updateRequests("Peer.remoteRejectedRequest")
1280 c.decExpectedChunkReceive(r)
1284 func (c *Peer) decExpectedChunkReceive(r RequestIndex) {
1285 count := c.validReceiveChunks[r]
1287 delete(c.validReceiveChunks, r)
1288 } else if count > 1 {
1289 c.validReceiveChunks[r] = count - 1
1295 func (c *PeerConn) onReadExtendedMsg(id pp.ExtensionNumber, payload []byte) (err error) {
1297 // TODO: Should we still do this?
1299 // These clients use their own extension IDs for outgoing message
1300 // types, which is incorrect.
1301 if bytes.HasPrefix(c.PeerID[:], []byte("-SD0100-")) || strings.HasPrefix(string(c.PeerID[:]), "-XL0012-") {
1309 case pp.HandshakeExtendedID:
1310 var d pp.ExtendedHandshakeMessage
1311 if err := bencode.Unmarshal(payload, &d); err != nil {
1312 c.logger.Printf("error parsing extended handshake message %q: %s", payload, err)
1313 return fmt.Errorf("unmarshalling extended handshake payload: %w", err)
1315 if cb := c.callbacks.ReadExtendedHandshake; cb != nil {
1318 // c.logger.WithDefaultLevel(log.Debug).Printf("received extended handshake message:\n%s", spew.Sdump(d))
1320 c.PeerMaxRequests = d.Reqq
1322 c.PeerClientName.Store(d.V)
1323 if c.PeerExtensionIDs == nil {
1324 c.PeerExtensionIDs = make(map[pp.ExtensionName]pp.ExtensionNumber, len(d.M))
1326 c.PeerListenPort = d.Port
1327 c.PeerPrefersEncryption = d.Encryption
1328 for name, id := range d.M {
1329 if _, ok := c.PeerExtensionIDs[name]; !ok {
1330 peersSupportingExtension.Add(
1331 // expvar.Var.String must produce valid JSON. "ut_payme\xeet_address" was being
1332 // entered here which caused problems later when unmarshalling.
1333 strconv.Quote(string(name)),
1336 c.PeerExtensionIDs[name] = id
1338 if d.MetadataSize != 0 {
1339 if err = t.setMetadataSize(d.MetadataSize); err != nil {
1340 return fmt.Errorf("setting metadata size to %d: %w", d.MetadataSize, err)
1343 c.requestPendingMetadata()
1344 if !t.cl.config.DisablePEX {
1345 t.pex.Add(c) // we learnt enough now
1349 case metadataExtendedId:
1350 err := cl.gotMetadataExtensionMsg(payload, t, c)
1352 return fmt.Errorf("handling metadata extension message: %w", err)
1356 if !c.pex.IsEnabled() {
1357 return nil // or hang-up maybe?
1359 return c.pex.Recv(payload)
1361 return fmt.Errorf("unexpected extended message ID: %v", id)
1365 // Set both the Reader and Writer for the connection from a single ReadWriter.
1366 func (cn *PeerConn) setRW(rw io.ReadWriter) {
1371 // Returns the Reader and Writer as a combined ReadWriter.
1372 func (cn *PeerConn) rw() io.ReadWriter {
1379 func (c *Peer) doChunkReadStats(size int64) {
1380 c.allStats(func(cs *ConnStats) { cs.receivedChunk(size) })
1383 // Handle a received chunk from a peer.
1384 func (c *Peer) receiveChunk(msg *pp.Message) error {
1385 chunksReceived.Add("total", 1)
1387 ppReq := newRequestFromMessage(msg)
1388 req := c.t.requestIndexFromRequest(ppReq)
1391 chunksReceived.Add("while choked", 1)
1394 if c.validReceiveChunks[req] <= 0 {
1395 chunksReceived.Add("unexpected", 1)
1396 return errors.New("received unexpected chunk")
1398 c.decExpectedChunkReceive(req)
1400 if c.peerChoking && c.peerAllowedFast.Contains(bitmap.BitIndex(ppReq.Index)) {
1401 chunksReceived.Add("due to allowed fast", 1)
1404 // The request needs to be deleted immediately to prevent cancels occurring asynchronously when
1405 // have actually already received the piece, while we have the Client unlocked to write the data
1409 if c.requestState.Requests.Contains(req) {
1410 for _, f := range c.callbacks.ReceivedRequested {
1411 f(PeerMessageEvent{c, msg})
1414 // Request has been satisfied.
1415 if c.deleteRequest(req) || c.requestState.Cancelled.CheckedRemove(req) {
1418 c._chunksReceivedWhileExpecting++
1420 if c.isLowOnRequests() {
1421 c.updateRequests("Peer.receiveChunk deleted request")
1424 chunksReceived.Add("unintended", 1)
1431 // Do we actually want this chunk?
1432 if t.haveChunk(ppReq) {
1433 // panic(fmt.Sprintf("%+v", ppReq))
1434 chunksReceived.Add("redundant", 1)
1435 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadWasted }))
1439 piece := &t.pieces[ppReq.Index]
1441 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadUseful }))
1442 c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulData }))
1444 c.piecesReceivedSinceLastRequestUpdate++
1445 c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulIntendedData }))
1447 for _, f := range c.t.cl.config.Callbacks.ReceivedUsefulData {
1448 f(ReceivedUsefulDataEvent{c, msg})
1450 c.lastUsefulChunkReceived = time.Now()
1452 // Need to record that it hasn't been written yet, before we attempt to do
1453 // anything with it.
1454 piece.incrementPendingWrites()
1455 // Record that we have the chunk, so we aren't trying to download it while
1456 // waiting for it to be written to storage.
1457 piece.unpendChunkIndex(chunkIndexFromChunkSpec(ppReq.ChunkSpec, t.chunkSize))
1459 // Cancel pending requests for this chunk from *other* peers.
1460 if p := t.pendingRequests[req]; p != nil {
1462 panic("should not be pending request from conn that just received it")
1467 err := func() error {
1470 concurrentChunkWrites.Add(1)
1471 defer concurrentChunkWrites.Add(-1)
1472 // Write the chunk out. Note that the upper bound on chunk writing concurrency will be the
1473 // number of connections. We write inline with receiving the chunk (with this lock dance),
1474 // because we want to handle errors synchronously and I haven't thought of a nice way to
1475 // defer any concurrency to the storage and have that notify the client of errors. TODO: Do
1477 return t.writeChunk(int(msg.Index), int64(msg.Begin), msg.Piece)
1480 piece.decrementPendingWrites()
1483 c.logger.WithDefaultLevel(log.Error).Printf("writing received chunk %v: %v", req, err)
1485 // Necessary to pass TestReceiveChunkStorageFailureSeederFastExtensionDisabled. I think a
1486 // request update runs while we're writing the chunk that just failed. Then we never do a
1487 // fresh update after pending the failed request.
1488 c.updateRequests("Peer.receiveChunk error writing chunk")
1489 t.onWriteChunkErr(err)
1493 c.onDirtiedPiece(pieceIndex(ppReq.Index))
1495 // We need to ensure the piece is only queued once, so only the last chunk writer gets this job.
1496 if t.pieceAllDirty(pieceIndex(ppReq.Index)) && piece.pendingWrites == 0 {
1497 t.queuePieceCheck(pieceIndex(ppReq.Index))
1498 // We don't pend all chunks here anymore because we don't want code dependent on the dirty
1499 // chunk status (such as the haveChunk call above) to have to check all the various other
1500 // piece states like queued for hash, hashing etc. This does mean that we need to be sure
1501 // that chunk pieces are pended at an appropriate time later however.
1504 cl.event.Broadcast()
1505 // We do this because we've written a chunk, and may change PieceState.Partial.
1506 t.publishPieceChange(pieceIndex(ppReq.Index))
1511 func (c *Peer) onDirtiedPiece(piece pieceIndex) {
1512 if c.peerTouchedPieces == nil {
1513 c.peerTouchedPieces = make(map[pieceIndex]struct{})
1515 c.peerTouchedPieces[piece] = struct{}{}
1516 ds := &c.t.pieces[piece].dirtiers
1518 *ds = make(map[*Peer]struct{})
1520 (*ds)[c] = struct{}{}
1523 func (c *PeerConn) uploadAllowed() bool {
1524 if c.t.cl.config.NoUpload {
1527 if c.t.dataUploadDisallowed {
1533 if !c.peerHasWantedPieces() {
1536 // Don't upload more than 100 KiB more than we download.
1537 if c._stats.BytesWrittenData.Int64() >= c._stats.BytesReadData.Int64()+100<<10 {
1543 func (c *PeerConn) setRetryUploadTimer(delay time.Duration) {
1544 if c.uploadTimer == nil {
1545 c.uploadTimer = time.AfterFunc(delay, c.tickleWriter)
1547 c.uploadTimer.Reset(delay)
1551 // Also handles choking and unchoking of the remote peer.
1552 func (c *PeerConn) upload(msg func(pp.Message) bool) bool {
1553 // Breaking or completing this loop means we don't want to upload to the
1554 // peer anymore, and we choke them.
1556 for c.uploadAllowed() {
1557 // We want to upload to the peer.
1558 if !c.unchoke(msg) {
1561 for r, state := range c.peerRequests {
1562 if state.data == nil {
1565 res := c.t.cl.config.UploadRateLimiter.ReserveN(time.Now(), int(r.Length))
1567 panic(fmt.Sprintf("upload rate limiter burst size < %d", r.Length))
1569 delay := res.Delay()
1572 c.setRetryUploadTimer(delay)
1573 // Hard to say what to return here.
1576 more := c.sendChunk(r, msg, state)
1577 delete(c.peerRequests, r)
1588 func (cn *PeerConn) drop() {
1589 cn.t.dropConnection(cn)
1592 func (cn *Peer) netGoodPiecesDirtied() int64 {
1593 return cn._stats.PiecesDirtiedGood.Int64() - cn._stats.PiecesDirtiedBad.Int64()
1596 func (c *Peer) peerHasWantedPieces() bool {
1597 if all, _ := c.peerHasAllPieces(); all {
1598 return !c.t.haveAllPieces() && !c.t._pendingPieces.IsEmpty()
1600 if !c.t.haveInfo() {
1601 return !c.peerPieces().IsEmpty()
1603 return c.peerPieces().Intersects(&c.t._pendingPieces)
1606 // Returns true if an outstanding request is removed. Cancelled requests should be handled
1608 func (c *Peer) deleteRequest(r RequestIndex) bool {
1609 if !c.requestState.Requests.CheckedRemove(r) {
1612 for _, f := range c.callbacks.DeletedRequest {
1613 f(PeerRequestEvent{c, c.t.requestIndexToRequest(r)})
1615 c.updateExpectingChunks()
1616 if c.t.requestingPeer(r) != c {
1617 panic("only one peer should have a given request at a time")
1619 delete(c.t.pendingRequests, r)
1620 delete(c.t.lastRequested, r)
1621 // c.t.iterPeers(func(p *Peer) {
1622 // if p.isLowOnRequests() {
1623 // p.updateRequests("Peer.deleteRequest")
1629 func (c *Peer) deleteAllRequests() (deleted *roaring.Bitmap) {
1630 deleted = c.requestState.Requests.Clone()
1631 deleted.Iterate(func(x uint32) bool {
1632 if !c.deleteRequest(x) {
1633 panic("request should exist")
1637 c.assertNoRequests()
1641 func (c *Peer) assertNoRequests() {
1642 if !c.requestState.Requests.IsEmpty() {
1643 panic(c.requestState.Requests.GetCardinality())
1647 func (c *Peer) cancelAllRequests() (cancelled *roaring.Bitmap) {
1648 cancelled = c.requestState.Requests.Clone()
1649 cancelled.Iterate(func(x uint32) bool {
1653 c.assertNoRequests()
1657 // This is called when something has changed that should wake the writer, such as putting stuff into
1658 // the writeBuffer, or changing some state that the writer can act on.
1659 func (c *PeerConn) tickleWriter() {
1660 c.messageWriter.writeCond.Broadcast()
1663 func (c *PeerConn) sendChunk(r Request, msg func(pp.Message) bool, state *peerRequestState) (more bool) {
1664 c.lastChunkSent = time.Now()
1665 return msg(pp.Message{
1673 func (c *PeerConn) setTorrent(t *Torrent) {
1675 panic("connection already associated with a torrent")
1678 c.logger.WithDefaultLevel(log.Debug).Printf("set torrent=%v", t)
1679 t.reconcileHandshakeStats(c)
1682 func (c *Peer) peerPriority() (peerPriority, error) {
1683 return bep40Priority(c.remoteIpPort(), c.t.cl.publicAddr(c.remoteIp()))
1686 func (c *Peer) remoteIp() net.IP {
1687 host, _, _ := net.SplitHostPort(c.RemoteAddr.String())
1688 return net.ParseIP(host)
1691 func (c *Peer) remoteIpPort() IpPort {
1692 ipa, _ := tryIpPortFromNetAddr(c.RemoteAddr)
1693 return IpPort{ipa.IP, uint16(ipa.Port)}
1696 func (c *PeerConn) pexPeerFlags() pp.PexPeerFlags {
1697 f := pp.PexPeerFlags(0)
1698 if c.PeerPrefersEncryption {
1699 f |= pp.PexPrefersEncryption
1702 f |= pp.PexOutgoingConn
1705 f |= pp.PexSupportsUtp
1710 // This returns the address to use if we want to dial the peer again. It incorporates the peer's
1711 // advertised listen port.
1712 func (c *PeerConn) dialAddr() PeerRemoteAddr {
1713 if !c.outgoing && c.PeerListenPort != 0 {
1714 switch addr := c.RemoteAddr.(type) {
1717 dialAddr.Port = c.PeerListenPort
1721 dialAddr.Port = c.PeerListenPort
1728 func (c *PeerConn) pexEvent(t pexEventType) pexEvent {
1729 f := c.pexPeerFlags()
1730 addr := c.dialAddr()
1731 return pexEvent{t, addr, f, nil}
1734 func (c *PeerConn) String() string {
1735 return fmt.Sprintf("%T %p [id=%q, exts=%v, v=%q]", c, c, c.PeerID, c.PeerExtensionBytes, c.PeerClientName.Load())
1738 func (c *Peer) trust() connectionTrust {
1739 return connectionTrust{c.trusted, c.netGoodPiecesDirtied()}
1742 type connectionTrust struct {
1744 NetGoodPiecesDirted int64
1747 func (l connectionTrust) Less(r connectionTrust) bool {
1748 return multiless.New().Bool(l.Implicit, r.Implicit).Int64(l.NetGoodPiecesDirted, r.NetGoodPiecesDirted).Less()
1751 // Returns the pieces the peer could have based on their claims. If we don't know how many pieces
1752 // are in the torrent, it could be a very large range the peer has sent HaveAll.
1753 func (cn *PeerConn) PeerPieces() *roaring.Bitmap {
1755 defer cn.locker().RUnlock()
1756 return cn.newPeerPieces()
1759 // Returns a new Bitmap that includes bits for all pieces the peer could have based on their claims.
1760 func (cn *Peer) newPeerPieces() *roaring.Bitmap {
1761 // TODO: Can we use copy on write?
1762 ret := cn.peerPieces().Clone()
1763 if all, _ := cn.peerHasAllPieces(); all {
1764 if cn.t.haveInfo() {
1765 ret.AddRange(0, bitmap.BitRange(cn.t.numPieces()))
1767 ret.AddRange(0, bitmap.ToEnd)
1773 func (cn *Peer) stats() *ConnStats {
1777 func (p *Peer) TryAsPeerConn() (*PeerConn, bool) {
1778 pc, ok := p.peerImpl.(*PeerConn)
1782 func (p *Peer) uncancelledRequests() uint64 {
1783 return p.requestState.Requests.GetCardinality()
1786 func (pc *PeerConn) remoteIsTransmission() bool {
1787 return bytes.HasPrefix(pc.PeerID[:], []byte("-TR")) && pc.PeerID[7] == '-'