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) (left, ok 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 for r := range cn.peerRequests {
532 // TODO: Don't reject pieces in allowed fast set.
536 cn.peerRequests = nil
541 func (cn *PeerConn) unchoke(msg func(pp.Message) bool) bool {
546 return msg(pp.Message{
551 func (cn *Peer) setInterested(interested bool) bool {
552 if cn.requestState.Interested == interested {
555 cn.requestState.Interested = interested
557 cn.lastBecameInterested = time.Now()
558 } else if !cn.lastBecameInterested.IsZero() {
559 cn.priorInterest += time.Since(cn.lastBecameInterested)
561 cn.updateExpectingChunks()
562 // log.Printf("%p: setting interest: %v", cn, interested)
563 return cn.writeInterested(interested)
566 func (pc *PeerConn) writeInterested(interested bool) bool {
567 return pc.write(pp.Message{
568 Type: func() pp.MessageType {
572 return pp.NotInterested
578 // The function takes a message to be sent, and returns true if more messages
580 type messageWriter func(pp.Message) bool
582 // This function seems to only used by Peer.request. It's all logic checks, so maybe we can no-op it
583 // when we want to go fast.
584 func (cn *Peer) shouldRequest(r RequestIndex) error {
585 pi := pieceIndex(r / cn.t.chunksPerRegularPiece())
586 if cn.requestState.Cancelled.Contains(r) {
587 return errors.New("request is cancelled and waiting acknowledgement")
589 if !cn.peerHasPiece(pi) {
590 return errors.New("requesting piece peer doesn't have")
592 if !cn.t.peerIsActive(cn) {
593 panic("requesting but not in active conns")
595 if cn.closed.IsSet() {
596 panic("requesting when connection is closed")
598 if cn.t.hashingPiece(pi) {
599 panic("piece is being hashed")
601 if cn.t.pieceQueuedForHash(pi) {
602 panic("piece is queued for hash")
604 if cn.peerChoking && !cn.peerAllowedFast.Contains(bitmap.BitIndex(pi)) {
605 // This could occur if we made a request with the fast extension, and then got choked and
606 // haven't had the request rejected yet.
607 if !cn.requestState.Requests.Contains(r) {
608 panic("peer choking and piece not allowed fast")
614 func (cn *Peer) mustRequest(r RequestIndex) bool {
615 more, err := cn.request(r)
622 func (cn *Peer) request(r RequestIndex) (more bool, err error) {
623 if err := cn.shouldRequest(r); err != nil {
626 if cn.requestState.Requests.Contains(r) {
629 if maxRequests(cn.requestState.Requests.GetCardinality()) >= cn.nominalMaxRequests() {
630 return true, errors.New("too many outstanding requests")
632 cn.requestState.Requests.Add(r)
633 if cn.validReceiveChunks == nil {
634 cn.validReceiveChunks = make(map[RequestIndex]int)
636 cn.validReceiveChunks[r]++
637 cn.t.pendingRequests[r] = cn
638 cn.t.lastRequested[r] = time.Now()
639 cn.updateExpectingChunks()
640 ppReq := cn.t.requestIndexToRequest(r)
641 for _, f := range cn.callbacks.SentRequest {
642 f(PeerRequestEvent{cn, ppReq})
644 return cn.peerImpl._request(ppReq), nil
647 func (me *PeerConn) _request(r Request) bool {
648 return me.write(pp.Message{
656 func (me *Peer) cancel(r RequestIndex) {
657 if !me.deleteRequest(r) {
658 panic("request not existing should have been guarded")
661 if !me.requestState.Cancelled.CheckedAdd(r) {
662 panic("request already cancelled")
666 if me.isLowOnRequests() {
667 me.updateRequests("Peer.cancel")
671 func (me *PeerConn) _cancel(r RequestIndex) bool {
672 me.write(makeCancelMessage(me.t.requestIndexToRequest(r)))
673 // Transmission does not send rejects for received cancels. See
674 // https://github.com/transmission/transmission/pull/2275.
675 return me.fastEnabled() && !me.remoteIsTransmission()
678 func (cn *PeerConn) fillWriteBuffer() {
679 if cn.messageWriter.writeBuffer.Len() > writeBufferLowWaterLen {
680 // Fully committing to our max requests requires sufficient space (see
681 // maxLocalToRemoteRequests). Flush what we have instead. We also prefer always to make
682 // requests than to do PEX or upload, so we short-circuit before handling those. Any update
683 // request reason will not be cleared, so we'll come right back here when there's space. We
684 // can't do this in maybeUpdateActualRequestState because it's a method on Peer and has no
685 // knowledge of write buffers.
687 cn.maybeUpdateActualRequestState()
688 if cn.pex.IsEnabled() {
689 if flow := cn.pex.Share(cn.write); !flow {
696 func (cn *PeerConn) have(piece pieceIndex) {
697 if cn.sentHaves.Get(bitmap.BitIndex(piece)) {
702 Index: pp.Integer(piece),
704 cn.sentHaves.Add(bitmap.BitIndex(piece))
707 func (cn *PeerConn) postBitfield() {
708 if cn.sentHaves.Len() != 0 {
709 panic("bitfield must be first have-related message sent")
711 if !cn.t.haveAnyPieces() {
716 Bitfield: cn.t.bitfield(),
718 cn.sentHaves = bitmap.Bitmap{cn.t._completedPieces.Clone()}
721 // Sets a reason to update requests, and if there wasn't already one, handle it.
722 func (cn *Peer) updateRequests(reason string) {
723 if cn.needRequestUpdate != "" {
726 if reason != peerUpdateRequestsTimerReason && !cn.isLowOnRequests() {
729 cn.needRequestUpdate = reason
730 cn.handleUpdateRequests()
733 func (cn *PeerConn) handleUpdateRequests() {
734 // The writer determines the request state as needed when it can write.
738 // Emits the indices in the Bitmaps bms in order, never repeating any index.
739 // skip is mutated during execution, and its initial values will never be
741 func iterBitmapsDistinct(skip *bitmap.Bitmap, bms ...bitmap.Bitmap) iter.Func {
742 return func(cb iter.Callback) {
743 for _, bm := range bms {
745 func(_i interface{}) bool {
747 if skip.Contains(bitmap.BitIndex(i)) {
750 skip.Add(bitmap.BitIndex(i))
761 func (cn *Peer) peerPiecesChanged() {
762 cn.t.maybeDropMutuallyCompletePeer(cn)
765 func (cn *PeerConn) raisePeerMinPieces(newMin pieceIndex) {
766 if newMin > cn.peerMinPieces {
767 cn.peerMinPieces = newMin
771 func (cn *PeerConn) peerSentHave(piece pieceIndex) error {
772 if cn.t.haveInfo() && piece >= cn.t.numPieces() || piece < 0 {
773 return errors.New("invalid piece")
775 if cn.peerHasPiece(piece) {
778 cn.raisePeerMinPieces(piece + 1)
779 if !cn.peerHasPiece(piece) {
780 cn.t.incPieceAvailability(piece)
782 cn._peerPieces.Add(uint32(piece))
783 if cn.t.wantPieceIndex(piece) {
784 cn.updateRequests("have")
786 cn.peerPiecesChanged()
790 func (cn *PeerConn) peerSentBitfield(bf []bool) error {
792 panic("expected bitfield length divisible by 8")
794 // We know that the last byte means that at most the last 7 bits are wasted.
795 cn.raisePeerMinPieces(pieceIndex(len(bf) - 7))
796 if cn.t.haveInfo() && len(bf) > int(cn.t.numPieces()) {
797 // Ignore known excess pieces.
798 bf = bf[:cn.t.numPieces()]
800 bm := boolSliceToBitmap(bf)
801 if cn.t.haveInfo() && pieceIndex(bm.GetCardinality()) == cn.t.numPieces() {
802 cn.onPeerHasAllPieces()
806 cn.raisePeerMinPieces(pieceIndex(bm.Maximum()) + 1)
808 shouldUpdateRequests := false
809 if cn.peerSentHaveAll {
810 if !cn.t.deleteConnWithAllPieces(&cn.Peer) {
813 cn.peerSentHaveAll = false
814 if !cn._peerPieces.IsEmpty() {
815 panic("if peer has all, we expect no individual peer pieces to be set")
818 bm.Xor(&cn._peerPieces)
820 cn.peerSentHaveAll = false
821 // bm is now 'on' for pieces that are changing
822 bm.Iterate(func(x uint32) bool {
824 if cn._peerPieces.Contains(x) {
825 // Then we must be losing this piece
826 cn.t.decPieceAvailability(pi)
828 if !shouldUpdateRequests && cn.t.wantPieceIndex(pieceIndex(x)) {
829 shouldUpdateRequests = true
831 // We must be gaining this piece
832 cn.t.incPieceAvailability(pieceIndex(x))
836 // Apply the changes. If we had everything previously, this should be empty, so xor is the same
838 cn._peerPieces.Xor(&bm)
839 if shouldUpdateRequests {
840 cn.updateRequests("bitfield")
842 // We didn't guard this before, I see no reason to do it now.
843 cn.peerPiecesChanged()
847 func (cn *PeerConn) onPeerHasAllPieces() {
850 cn._peerPieces.Iterate(func(x uint32) bool {
851 t.decPieceAvailability(pieceIndex(x))
855 t.addConnWithAllPieces(&cn.Peer)
856 cn.peerSentHaveAll = true
857 cn._peerPieces.Clear()
858 if !cn.t._pendingPieces.IsEmpty() {
859 cn.updateRequests("Peer.onPeerHasAllPieces")
861 cn.peerPiecesChanged()
864 func (cn *PeerConn) onPeerSentHaveAll() error {
865 cn.onPeerHasAllPieces()
869 func (cn *PeerConn) peerSentHaveNone() error {
870 if cn.peerSentHaveAll {
871 cn.t.decPeerPieceAvailability(&cn.Peer)
873 cn._peerPieces.Clear()
874 cn.peerSentHaveAll = false
875 cn.peerPiecesChanged()
879 func (c *PeerConn) requestPendingMetadata() {
883 if c.PeerExtensionIDs[pp.ExtensionNameMetadata] == 0 {
884 // Peer doesn't support this.
887 // Request metadata pieces that we don't have in a random order.
889 for index := 0; index < c.t.metadataPieceCount(); index++ {
890 if !c.t.haveMetadataPiece(index) && !c.requestedMetadataPiece(index) {
891 pending = append(pending, index)
894 rand.Shuffle(len(pending), func(i, j int) { pending[i], pending[j] = pending[j], pending[i] })
895 for _, i := range pending {
896 c.requestMetadataPiece(i)
900 func (cn *PeerConn) wroteMsg(msg *pp.Message) {
901 torrent.Add(fmt.Sprintf("messages written of type %s", msg.Type.String()), 1)
902 if msg.Type == pp.Extended {
903 for name, id := range cn.PeerExtensionIDs {
904 if id != msg.ExtendedID {
907 torrent.Add(fmt.Sprintf("Extended messages written for protocol %q", name), 1)
910 cn.allStats(func(cs *ConnStats) { cs.wroteMsg(msg) })
913 // After handshake, we know what Torrent and Client stats to include for a
915 func (cn *Peer) postHandshakeStats(f func(*ConnStats)) {
921 // All ConnStats that include this connection. Some objects are not known
922 // until the handshake is complete, after which it's expected to reconcile the
924 func (cn *Peer) allStats(f func(*ConnStats)) {
926 if cn.reconciledHandshakeStats {
927 cn.postHandshakeStats(f)
931 func (cn *PeerConn) wroteBytes(n int64) {
932 cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesWritten }))
935 func (cn *Peer) readBytes(n int64) {
936 cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesRead }))
939 // Returns whether the connection could be useful to us. We're seeding and
940 // they want data, we don't have metainfo and they can provide it, etc.
941 func (c *Peer) useful() bool {
943 if c.closed.IsSet() {
947 return c.supportsExtension("ut_metadata")
949 if t.seeding() && c.peerInterested {
952 if c.peerHasWantedPieces() {
958 func (c *Peer) lastHelpful() (ret time.Time) {
959 ret = c.lastUsefulChunkReceived
960 if c.t.seeding() && c.lastChunkSent.After(ret) {
961 ret = c.lastChunkSent
966 func (c *PeerConn) fastEnabled() bool {
967 return c.PeerExtensionBytes.SupportsFast() && c.t.cl.config.Extensions.SupportsFast()
970 func (c *PeerConn) reject(r Request) {
971 if !c.fastEnabled() {
972 panic("fast not enabled")
974 c.write(r.ToMsg(pp.Reject))
975 delete(c.peerRequests, r)
978 func (c *PeerConn) onReadRequest(r Request) error {
979 requestedChunkLengths.Add(strconv.FormatUint(r.Length.Uint64(), 10), 1)
980 if _, ok := c.peerRequests[r]; ok {
981 torrent.Add("duplicate requests received", 1)
985 torrent.Add("requests received while choking", 1)
987 torrent.Add("requests rejected while choking", 1)
992 // TODO: What if they've already requested this?
993 if len(c.peerRequests) >= localClientReqq {
994 torrent.Add("requests received while queue full", 1)
998 // BEP 6 says we may close here if we choose.
1001 if !c.t.havePiece(pieceIndex(r.Index)) {
1002 // This isn't necessarily them screwing up. We can drop pieces
1003 // from our storage, and can't communicate this to peers
1004 // except by reconnecting.
1005 requestsReceivedForMissingPieces.Add(1)
1006 return fmt.Errorf("peer requested piece we don't have: %v", r.Index.Int())
1008 // Check this after we know we have the piece, so that the piece length will be known.
1009 if r.Begin+r.Length > c.t.pieceLength(pieceIndex(r.Index)) {
1010 torrent.Add("bad requests received", 1)
1011 return errors.New("bad Request")
1013 if c.peerRequests == nil {
1014 c.peerRequests = make(map[Request]*peerRequestState, localClientReqq)
1016 value := &peerRequestState{}
1017 c.peerRequests[r] = value
1018 go c.peerRequestDataReader(r, value)
1023 func (c *PeerConn) peerRequestDataReader(r Request, prs *peerRequestState) {
1024 b, err := readPeerRequestData(r, c)
1026 defer c.locker().Unlock()
1028 c.peerRequestDataReadFailed(err, r)
1031 panic("data must be non-nil to trigger send")
1033 torrent.Add("peer request data read successes", 1)
1039 // If this is maintained correctly, we might be able to support optional synchronous reading for
1040 // chunk sending, the way it used to work.
1041 func (c *PeerConn) peerRequestDataReadFailed(err error, r Request) {
1042 torrent.Add("peer request data read failures", 1)
1043 logLevel := log.Warning
1044 if c.t.hasStorageCap() {
1045 // It's expected that pieces might drop. See
1046 // https://github.com/anacrolix/torrent/issues/702#issuecomment-1000953313.
1047 logLevel = log.Debug
1049 c.logger.WithDefaultLevel(logLevel).Printf("error reading chunk for peer Request %v: %v", r, err)
1050 if c.t.closed.IsSet() {
1053 i := pieceIndex(r.Index)
1054 if c.t.pieceComplete(i) {
1055 // There used to be more code here that just duplicated the following break. Piece
1056 // completions are currently cached, so I'm not sure how helpful this update is, except to
1057 // pull any completion changes pushed to the storage backend in failed reads that got us
1059 c.t.updatePieceCompletion(i)
1061 // If we failed to send a chunk, choke the peer to ensure they flush all their requests. We've
1062 // probably dropped a piece from storage, but there's no way to communicate this to the peer. If
1063 // they ask for it again, we'll kick them to allow us to send them an updated bitfield on the
1064 // next connect. TODO: Support rejecting here too.
1066 c.logger.WithDefaultLevel(log.Warning).Printf("already choking peer, requests might not be rejected correctly")
1071 func readPeerRequestData(r Request, c *PeerConn) ([]byte, error) {
1072 b := make([]byte, r.Length)
1073 p := c.t.info.Piece(int(r.Index))
1074 n, err := c.t.readAt(b, p.Offset()+int64(r.Begin))
1081 panic("expected error")
1087 func runSafeExtraneous(f func()) {
1095 func (c *PeerConn) logProtocolBehaviour(level log.Level, format string, arg ...interface{}) {
1096 c.logger.WithLevel(level).WithContextText(fmt.Sprintf(
1097 "peer id %q, ext v %q", c.PeerID, c.PeerClientName.Load(),
1098 )).SkipCallers(1).Printf(format, arg...)
1101 // Processes incoming BitTorrent wire-protocol messages. The client lock is held upon entry and
1102 // exit. Returning will end the connection.
1103 func (c *PeerConn) mainReadLoop() (err error) {
1106 torrent.Add("connection.mainReadLoop returned with error", 1)
1108 torrent.Add("connection.mainReadLoop returned with no error", 1)
1114 decoder := pp.Decoder{
1115 R: bufio.NewReaderSize(c.r, 1<<17),
1116 MaxLength: 256 * 1024,
1124 err = decoder.Decode(&msg)
1126 if cb := c.callbacks.ReadMessage; cb != nil && err == nil {
1129 if t.closed.IsSet() || c.closed.IsSet() {
1135 c.lastMessageReceived = time.Now()
1137 receivedKeepalives.Add(1)
1140 messageTypesReceived.Add(msg.Type.String(), 1)
1141 if msg.Type.FastExtension() && !c.fastEnabled() {
1142 runSafeExtraneous(func() { torrent.Add("fast messages received when extension is disabled", 1) })
1143 return fmt.Errorf("received fast extension message (type=%v) but extension is disabled", msg.Type)
1150 if !c.fastEnabled() {
1151 if !c.deleteAllRequests().IsEmpty() {
1152 c.t.iterPeers(func(p *Peer) {
1153 if p.isLowOnRequests() {
1154 p.updateRequests("choked by non-fast PeerConn")
1159 // We don't decrement pending requests here, let's wait for the peer to either
1160 // reject or satisfy the outstanding requests. Additionally, some peers may unchoke
1161 // us and resume where they left off, we don't want to have piled on to those chunks
1162 // in the meanwhile. I think a peer's ability to abuse this should be limited: they
1163 // could let us request a lot of stuff, then choke us and never reject, but they're
1164 // only a single peer, our chunk balancing should smooth over this abuse.
1166 c.peerChoking = true
1167 c.updateExpectingChunks()
1170 // Some clients do this for some reason. Transmission doesn't error on this, so we
1171 // won't for consistency.
1172 c.logProtocolBehaviour(log.Debug, "received unchoke when already unchoked")
1175 c.peerChoking = false
1177 c.requestState.Requests.Iterate(func(x uint32) bool {
1178 if !c.peerAllowedFast.Contains(x / c.t.chunksPerRegularPiece()) {
1183 if preservedCount != 0 {
1184 // TODO: Yes this is a debug log but I'm not happy with the state of the logging lib
1186 c.logger.WithLevel(log.Debug).Printf(
1187 "%v requests were preserved while being choked (fast=%v)",
1190 torrent.Add("requestsPreservedThroughChoking", int64(preservedCount))
1192 if !c.t._pendingPieces.IsEmpty() {
1193 c.updateRequests("unchoked")
1195 c.updateExpectingChunks()
1197 c.peerInterested = true
1199 case pp.NotInterested:
1200 c.peerInterested = false
1201 // We don't clear their requests since it isn't clear in the spec.
1202 // We'll probably choke them for this, which will clear them if
1203 // appropriate, and is clearly specified.
1205 err = c.peerSentHave(pieceIndex(msg.Index))
1207 err = c.peerSentBitfield(msg.Bitfield)
1209 r := newRequestFromMessage(&msg)
1210 err = c.onReadRequest(r)
1212 c.doChunkReadStats(int64(len(msg.Piece)))
1213 err = c.receiveChunk(&msg)
1214 if len(msg.Piece) == int(t.chunkSize) {
1215 t.chunkPool.Put(&msg.Piece)
1218 err = fmt.Errorf("receiving chunk: %w", err)
1221 req := newRequestFromMessage(&msg)
1222 c.onPeerSentCancel(req)
1224 ipa, ok := tryIpPortFromNetAddr(c.RemoteAddr)
1228 pingAddr := net.UDPAddr{
1233 pingAddr.Port = int(msg.Port)
1235 cl.eachDhtServer(func(s DhtServer) {
1236 go s.Ping(&pingAddr)
1239 torrent.Add("suggests received", 1)
1240 log.Fmsg("peer suggested piece %d", msg.Index).AddValues(c, msg.Index).SetLevel(log.Debug).Log(c.t.logger)
1241 c.updateRequests("suggested")
1243 err = c.onPeerSentHaveAll()
1245 err = c.peerSentHaveNone()
1247 req := newRequestFromMessage(&msg)
1248 if !c.remoteRejectedRequest(c.t.requestIndexFromRequest(req)) {
1249 log.Printf("received invalid reject [request=%v, peer=%v]", req, c)
1250 err = fmt.Errorf("received invalid reject [request=%v]", req)
1252 case pp.AllowedFast:
1253 torrent.Add("allowed fasts received", 1)
1254 log.Fmsg("peer allowed fast: %d", msg.Index).AddValues(c).SetLevel(log.Debug).Log(c.t.logger)
1255 c.updateRequests("PeerConn.mainReadLoop allowed fast")
1257 err = c.onReadExtendedMsg(msg.ExtendedID, msg.ExtendedPayload)
1259 err = fmt.Errorf("received unknown message type: %#v", msg.Type)
1267 // Returns true if it was valid to reject the request.
1268 func (c *Peer) remoteRejectedRequest(r RequestIndex) bool {
1269 if c.deleteRequest(r) {
1271 } else if !c.requestState.Cancelled.CheckedRemove(r) {
1274 if c.isLowOnRequests() {
1275 c.updateRequests("Peer.remoteRejectedRequest")
1277 c.decExpectedChunkReceive(r)
1281 func (c *Peer) decExpectedChunkReceive(r RequestIndex) {
1282 count := c.validReceiveChunks[r]
1284 delete(c.validReceiveChunks, r)
1285 } else if count > 1 {
1286 c.validReceiveChunks[r] = count - 1
1292 func (c *PeerConn) onReadExtendedMsg(id pp.ExtensionNumber, payload []byte) (err error) {
1294 // TODO: Should we still do this?
1296 // These clients use their own extension IDs for outgoing message
1297 // types, which is incorrect.
1298 if bytes.HasPrefix(c.PeerID[:], []byte("-SD0100-")) || strings.HasPrefix(string(c.PeerID[:]), "-XL0012-") {
1306 case pp.HandshakeExtendedID:
1307 var d pp.ExtendedHandshakeMessage
1308 if err := bencode.Unmarshal(payload, &d); err != nil {
1309 c.logger.Printf("error parsing extended handshake message %q: %s", payload, err)
1310 return fmt.Errorf("unmarshalling extended handshake payload: %w", err)
1312 if cb := c.callbacks.ReadExtendedHandshake; cb != nil {
1315 // c.logger.WithDefaultLevel(log.Debug).Printf("received extended handshake message:\n%s", spew.Sdump(d))
1317 c.PeerMaxRequests = d.Reqq
1319 c.PeerClientName.Store(d.V)
1320 if c.PeerExtensionIDs == nil {
1321 c.PeerExtensionIDs = make(map[pp.ExtensionName]pp.ExtensionNumber, len(d.M))
1323 c.PeerListenPort = d.Port
1324 c.PeerPrefersEncryption = d.Encryption
1325 for name, id := range d.M {
1326 if _, ok := c.PeerExtensionIDs[name]; !ok {
1327 peersSupportingExtension.Add(
1328 // expvar.Var.String must produce valid JSON. "ut_payme\xeet_address" was being
1329 // entered here which caused problems later when unmarshalling.
1330 strconv.Quote(string(name)),
1333 c.PeerExtensionIDs[name] = id
1335 if d.MetadataSize != 0 {
1336 if err = t.setMetadataSize(d.MetadataSize); err != nil {
1337 return fmt.Errorf("setting metadata size to %d: %w", d.MetadataSize, err)
1340 c.requestPendingMetadata()
1341 if !t.cl.config.DisablePEX {
1342 t.pex.Add(c) // we learnt enough now
1346 case metadataExtendedId:
1347 err := cl.gotMetadataExtensionMsg(payload, t, c)
1349 return fmt.Errorf("handling metadata extension message: %w", err)
1353 if !c.pex.IsEnabled() {
1354 return nil // or hang-up maybe?
1356 return c.pex.Recv(payload)
1358 return fmt.Errorf("unexpected extended message ID: %v", id)
1362 // Set both the Reader and Writer for the connection from a single ReadWriter.
1363 func (cn *PeerConn) setRW(rw io.ReadWriter) {
1368 // Returns the Reader and Writer as a combined ReadWriter.
1369 func (cn *PeerConn) rw() io.ReadWriter {
1376 func (c *Peer) doChunkReadStats(size int64) {
1377 c.allStats(func(cs *ConnStats) { cs.receivedChunk(size) })
1380 // Handle a received chunk from a peer.
1381 func (c *Peer) receiveChunk(msg *pp.Message) error {
1382 chunksReceived.Add("total", 1)
1384 ppReq := newRequestFromMessage(msg)
1385 req := c.t.requestIndexFromRequest(ppReq)
1388 chunksReceived.Add("while choked", 1)
1391 if c.validReceiveChunks[req] <= 0 {
1392 chunksReceived.Add("unexpected", 1)
1393 return errors.New("received unexpected chunk")
1395 c.decExpectedChunkReceive(req)
1397 if c.peerChoking && c.peerAllowedFast.Contains(bitmap.BitIndex(ppReq.Index)) {
1398 chunksReceived.Add("due to allowed fast", 1)
1401 // The request needs to be deleted immediately to prevent cancels occurring asynchronously when
1402 // have actually already received the piece, while we have the Client unlocked to write the data
1406 if c.requestState.Requests.Contains(req) {
1407 for _, f := range c.callbacks.ReceivedRequested {
1408 f(PeerMessageEvent{c, msg})
1411 // Request has been satisfied.
1412 if c.deleteRequest(req) || c.requestState.Cancelled.CheckedRemove(req) {
1415 c._chunksReceivedWhileExpecting++
1417 if c.isLowOnRequests() {
1418 c.updateRequests("Peer.receiveChunk deleted request")
1421 chunksReceived.Add("unintended", 1)
1428 // Do we actually want this chunk?
1429 if t.haveChunk(ppReq) {
1430 // panic(fmt.Sprintf("%+v", ppReq))
1431 chunksReceived.Add("redundant", 1)
1432 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadWasted }))
1436 piece := &t.pieces[ppReq.Index]
1438 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadUseful }))
1439 c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulData }))
1441 c.piecesReceivedSinceLastRequestUpdate++
1442 c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulIntendedData }))
1444 for _, f := range c.t.cl.config.Callbacks.ReceivedUsefulData {
1445 f(ReceivedUsefulDataEvent{c, msg})
1447 c.lastUsefulChunkReceived = time.Now()
1449 // Need to record that it hasn't been written yet, before we attempt to do
1450 // anything with it.
1451 piece.incrementPendingWrites()
1452 // Record that we have the chunk, so we aren't trying to download it while
1453 // waiting for it to be written to storage.
1454 piece.unpendChunkIndex(chunkIndexFromChunkSpec(ppReq.ChunkSpec, t.chunkSize))
1456 // Cancel pending requests for this chunk from *other* peers.
1457 if p := t.pendingRequests[req]; p != nil {
1459 panic("should not be pending request from conn that just received it")
1464 err := func() error {
1467 concurrentChunkWrites.Add(1)
1468 defer concurrentChunkWrites.Add(-1)
1469 // Write the chunk out. Note that the upper bound on chunk writing concurrency will be the
1470 // number of connections. We write inline with receiving the chunk (with this lock dance),
1471 // because we want to handle errors synchronously and I haven't thought of a nice way to
1472 // defer any concurrency to the storage and have that notify the client of errors. TODO: Do
1474 return t.writeChunk(int(msg.Index), int64(msg.Begin), msg.Piece)
1477 piece.decrementPendingWrites()
1480 c.logger.WithDefaultLevel(log.Error).Printf("writing received chunk %v: %v", req, err)
1482 // Necessary to pass TestReceiveChunkStorageFailureSeederFastExtensionDisabled. I think a
1483 // request update runs while we're writing the chunk that just failed. Then we never do a
1484 // fresh update after pending the failed request.
1485 c.updateRequests("Peer.receiveChunk error writing chunk")
1486 t.onWriteChunkErr(err)
1490 c.onDirtiedPiece(pieceIndex(ppReq.Index))
1492 // We need to ensure the piece is only queued once, so only the last chunk writer gets this job.
1493 if t.pieceAllDirty(pieceIndex(ppReq.Index)) && piece.pendingWrites == 0 {
1494 t.queuePieceCheck(pieceIndex(ppReq.Index))
1495 // We don't pend all chunks here anymore because we don't want code dependent on the dirty
1496 // chunk status (such as the haveChunk call above) to have to check all the various other
1497 // piece states like queued for hash, hashing etc. This does mean that we need to be sure
1498 // that chunk pieces are pended at an appropriate time later however.
1501 cl.event.Broadcast()
1502 // We do this because we've written a chunk, and may change PieceState.Partial.
1503 t.publishPieceChange(pieceIndex(ppReq.Index))
1508 func (c *Peer) onDirtiedPiece(piece pieceIndex) {
1509 if c.peerTouchedPieces == nil {
1510 c.peerTouchedPieces = make(map[pieceIndex]struct{})
1512 c.peerTouchedPieces[piece] = struct{}{}
1513 ds := &c.t.pieces[piece].dirtiers
1515 *ds = make(map[*Peer]struct{})
1517 (*ds)[c] = struct{}{}
1520 func (c *PeerConn) uploadAllowed() bool {
1521 if c.t.cl.config.NoUpload {
1524 if c.t.dataUploadDisallowed {
1530 if !c.peerHasWantedPieces() {
1533 // Don't upload more than 100 KiB more than we download.
1534 if c._stats.BytesWrittenData.Int64() >= c._stats.BytesReadData.Int64()+100<<10 {
1540 func (c *PeerConn) setRetryUploadTimer(delay time.Duration) {
1541 if c.uploadTimer == nil {
1542 c.uploadTimer = time.AfterFunc(delay, c.tickleWriter)
1544 c.uploadTimer.Reset(delay)
1548 // Also handles choking and unchoking of the remote peer.
1549 func (c *PeerConn) upload(msg func(pp.Message) bool) bool {
1550 // Breaking or completing this loop means we don't want to upload to the
1551 // peer anymore, and we choke them.
1553 for c.uploadAllowed() {
1554 // We want to upload to the peer.
1555 if !c.unchoke(msg) {
1558 for r, state := range c.peerRequests {
1559 if state.data == nil {
1562 res := c.t.cl.config.UploadRateLimiter.ReserveN(time.Now(), int(r.Length))
1564 panic(fmt.Sprintf("upload rate limiter burst size < %d", r.Length))
1566 delay := res.Delay()
1569 c.setRetryUploadTimer(delay)
1570 // Hard to say what to return here.
1573 more := c.sendChunk(r, msg, state)
1574 delete(c.peerRequests, r)
1585 func (cn *PeerConn) drop() {
1586 cn.t.dropConnection(cn)
1589 func (cn *Peer) netGoodPiecesDirtied() int64 {
1590 return cn._stats.PiecesDirtiedGood.Int64() - cn._stats.PiecesDirtiedBad.Int64()
1593 func (c *Peer) peerHasWantedPieces() bool {
1594 if all, _ := c.peerHasAllPieces(); all {
1595 return !c.t.haveAllPieces() && !c.t._pendingPieces.IsEmpty()
1597 if !c.t.haveInfo() {
1598 return !c.peerPieces().IsEmpty()
1600 return c.peerPieces().Intersects(&c.t._pendingPieces)
1603 // Returns true if an outstanding request is removed. Cancelled requests should be handled
1605 func (c *Peer) deleteRequest(r RequestIndex) bool {
1606 if !c.requestState.Requests.CheckedRemove(r) {
1609 for _, f := range c.callbacks.DeletedRequest {
1610 f(PeerRequestEvent{c, c.t.requestIndexToRequest(r)})
1612 c.updateExpectingChunks()
1613 if c.t.requestingPeer(r) != c {
1614 panic("only one peer should have a given request at a time")
1616 delete(c.t.pendingRequests, r)
1617 delete(c.t.lastRequested, r)
1618 // c.t.iterPeers(func(p *Peer) {
1619 // if p.isLowOnRequests() {
1620 // p.updateRequests("Peer.deleteRequest")
1626 func (c *Peer) deleteAllRequests() (deleted *roaring.Bitmap) {
1627 deleted = c.requestState.Requests.Clone()
1628 deleted.Iterate(func(x uint32) bool {
1629 if !c.deleteRequest(x) {
1630 panic("request should exist")
1634 c.assertNoRequests()
1638 func (c *Peer) assertNoRequests() {
1639 if !c.requestState.Requests.IsEmpty() {
1640 panic(c.requestState.Requests.GetCardinality())
1644 func (c *Peer) cancelAllRequests() (cancelled *roaring.Bitmap) {
1645 cancelled = c.requestState.Requests.Clone()
1646 cancelled.Iterate(func(x uint32) bool {
1650 c.assertNoRequests()
1654 // This is called when something has changed that should wake the writer, such as putting stuff into
1655 // the writeBuffer, or changing some state that the writer can act on.
1656 func (c *PeerConn) tickleWriter() {
1657 c.messageWriter.writeCond.Broadcast()
1660 func (c *PeerConn) sendChunk(r Request, msg func(pp.Message) bool, state *peerRequestState) (more bool) {
1661 c.lastChunkSent = time.Now()
1662 return msg(pp.Message{
1670 func (c *PeerConn) setTorrent(t *Torrent) {
1672 panic("connection already associated with a torrent")
1675 c.logger.WithDefaultLevel(log.Debug).Printf("set torrent=%v", t)
1676 t.reconcileHandshakeStats(c)
1679 func (c *Peer) peerPriority() (peerPriority, error) {
1680 return bep40Priority(c.remoteIpPort(), c.t.cl.publicAddr(c.remoteIp()))
1683 func (c *Peer) remoteIp() net.IP {
1684 host, _, _ := net.SplitHostPort(c.RemoteAddr.String())
1685 return net.ParseIP(host)
1688 func (c *Peer) remoteIpPort() IpPort {
1689 ipa, _ := tryIpPortFromNetAddr(c.RemoteAddr)
1690 return IpPort{ipa.IP, uint16(ipa.Port)}
1693 func (c *PeerConn) pexPeerFlags() pp.PexPeerFlags {
1694 f := pp.PexPeerFlags(0)
1695 if c.PeerPrefersEncryption {
1696 f |= pp.PexPrefersEncryption
1699 f |= pp.PexOutgoingConn
1702 f |= pp.PexSupportsUtp
1707 // This returns the address to use if we want to dial the peer again. It incorporates the peer's
1708 // advertised listen port.
1709 func (c *PeerConn) dialAddr() PeerRemoteAddr {
1710 if !c.outgoing && c.PeerListenPort != 0 {
1711 switch addr := c.RemoteAddr.(type) {
1714 dialAddr.Port = c.PeerListenPort
1718 dialAddr.Port = c.PeerListenPort
1725 func (c *PeerConn) pexEvent(t pexEventType) pexEvent {
1726 f := c.pexPeerFlags()
1727 addr := c.dialAddr()
1728 return pexEvent{t, addr, f, nil}
1731 func (c *PeerConn) String() string {
1732 return fmt.Sprintf("%T %p [id=%q, exts=%v, v=%q]", c, c, c.PeerID, c.PeerExtensionBytes, c.PeerClientName.Load())
1735 func (c *Peer) trust() connectionTrust {
1736 return connectionTrust{c.trusted, c.netGoodPiecesDirtied()}
1739 type connectionTrust struct {
1741 NetGoodPiecesDirted int64
1744 func (l connectionTrust) Less(r connectionTrust) bool {
1745 return multiless.New().Bool(l.Implicit, r.Implicit).Int64(l.NetGoodPiecesDirted, r.NetGoodPiecesDirted).Less()
1748 // Returns the pieces the peer could have based on their claims. If we don't know how many pieces
1749 // are in the torrent, it could be a very large range the peer has sent HaveAll.
1750 func (cn *PeerConn) PeerPieces() *roaring.Bitmap {
1752 defer cn.locker().RUnlock()
1753 return cn.newPeerPieces()
1756 // Returns a new Bitmap that includes bits for all pieces the peer could have based on their claims.
1757 func (cn *Peer) newPeerPieces() *roaring.Bitmap {
1758 // TODO: Can we use copy on write?
1759 ret := cn.peerPieces().Clone()
1760 if all, _ := cn.peerHasAllPieces(); all {
1761 if cn.t.haveInfo() {
1762 ret.AddRange(0, bitmap.BitRange(cn.t.numPieces()))
1764 ret.AddRange(0, bitmap.ToEnd)
1770 func (cn *Peer) stats() *ConnStats {
1774 func (p *Peer) TryAsPeerConn() (*PeerConn, bool) {
1775 pc, ok := p.peerImpl.(*PeerConn)
1779 func (p *Peer) uncancelledRequests() uint64 {
1780 return p.requestState.Requests.GetCardinality()
1783 func (pc *PeerConn) remoteIsTransmission() bool {
1784 return bytes.HasPrefix(pc.PeerID[:], []byte("-TR")) && pc.PeerID[7] == '-'