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"
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 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 requestState
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 roaring.Bitmap
125 PeerMaxRequests maxRequests // Maximum pending requests the peer allows.
126 PeerExtensionIDs map[pp.ExtensionName]pp.ExtensionNumber
127 PeerClientName atomic.Value
132 // Maintains the state of a BitTorrent-protocol based connection with a peer.
133 type PeerConn struct {
136 // A string that should identify the PeerConn's net.Conn endpoints. The net.Conn could
137 // be wrapping WebRTC, uTP, or TCP etc. Used in writing the conn status for peers.
142 PeerExtensionBytes pp.PeerExtensionBits
144 // The actual Conn, used for closing, and setting socket options. Do not use methods on this
145 // while holding any mutexes.
147 // The Reader and Writer for this Conn, with hooks installed for stats,
148 // limiting, deadlines etc.
152 messageWriter peerConnMsgWriter
154 uploadTimer *time.Timer
157 // The pieces the peer has claimed to have.
158 _peerPieces roaring.Bitmap
159 // The peer has everything. This can occur due to a special message, when
160 // we may not even know the number of pieces in the torrent yet.
164 func (cn *PeerConn) connStatusString() string {
165 return fmt.Sprintf("%+-55q %s %s", cn.PeerID, cn.PeerExtensionBytes, cn.connString)
168 func (cn *Peer) updateExpectingChunks() {
169 if cn.expectingChunks() {
170 if cn.lastStartedExpectingToReceiveChunks.IsZero() {
171 cn.lastStartedExpectingToReceiveChunks = time.Now()
174 if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
175 cn.cumulativeExpectedToReceiveChunks += time.Since(cn.lastStartedExpectingToReceiveChunks)
176 cn.lastStartedExpectingToReceiveChunks = time.Time{}
181 func (cn *Peer) expectingChunks() bool {
182 if cn.requestState.Requests.IsEmpty() {
185 if !cn.requestState.Interested {
191 haveAllowedFastRequests := false
192 cn.peerAllowedFast.Iterate(func(i uint32) bool {
193 haveAllowedFastRequests = roaringBitmapRangeCardinality(
194 &cn.requestState.Requests,
195 cn.t.pieceRequestIndexOffset(pieceIndex(i)),
196 cn.t.pieceRequestIndexOffset(pieceIndex(i+1)),
198 return !haveAllowedFastRequests
200 return haveAllowedFastRequests
203 func (cn *Peer) remoteChokingPiece(piece pieceIndex) bool {
204 return cn.peerChoking && !cn.peerAllowedFast.Contains(bitmap.BitIndex(piece))
207 // Returns true if the connection is over IPv6.
208 func (cn *PeerConn) ipv6() bool {
213 return len(ip) == net.IPv6len
216 // Returns true the if the dialer/initiator has the lower client peer ID. TODO: Find the
217 // specification for this.
218 func (cn *PeerConn) isPreferredDirection() bool {
219 return bytes.Compare(cn.t.cl.peerID[:], cn.PeerID[:]) < 0 == cn.outgoing
222 // Returns whether the left connection should be preferred over the right one,
223 // considering only their networking properties. If ok is false, we can't
225 func (l *PeerConn) hasPreferredNetworkOver(r *PeerConn) bool {
226 var ml multiless.Computation
227 ml = ml.Bool(r.isPreferredDirection(), l.isPreferredDirection())
228 ml = ml.Bool(l.utp(), r.utp())
229 ml = ml.Bool(r.ipv6(), l.ipv6())
233 func (cn *Peer) cumInterest() time.Duration {
234 ret := cn.priorInterest
235 if cn.requestState.Interested {
236 ret += time.Since(cn.lastBecameInterested)
241 func (cn *PeerConn) peerHasAllPieces() (all, known bool) {
242 if cn.peerSentHaveAll {
245 if !cn.t.haveInfo() {
248 return cn._peerPieces.GetCardinality() == uint64(cn.t.numPieces()), true
251 func (cn *Peer) locker() *lockWithDeferreds {
252 return cn.t.cl.locker()
255 func (cn *Peer) supportsExtension(ext pp.ExtensionName) bool {
256 _, ok := cn.PeerExtensionIDs[ext]
260 // The best guess at number of pieces in the torrent for this peer.
261 func (cn *Peer) bestPeerNumPieces() pieceIndex {
263 return cn.t.numPieces()
265 return cn.peerMinPieces
268 func (cn *Peer) completedString() string {
269 have := pieceIndex(cn.peerPieces().GetCardinality())
270 if all, _ := cn.peerHasAllPieces(); all {
271 have = cn.bestPeerNumPieces()
273 return fmt.Sprintf("%d/%d", have, cn.bestPeerNumPieces())
276 func (cn *PeerConn) onGotInfo(info *metainfo.Info) {
277 cn.setNumPieces(info.NumPieces())
280 // Correct the PeerPieces slice length. Return false if the existing slice is invalid, such as by
281 // receiving badly sized BITFIELD, or invalid HAVE messages.
282 func (cn *PeerConn) setNumPieces(num pieceIndex) {
283 cn._peerPieces.RemoveRange(bitmap.BitRange(num), bitmap.ToEnd)
284 cn.peerPiecesChanged()
287 func (cn *PeerConn) peerPieces() *roaring.Bitmap {
288 return &cn._peerPieces
291 func eventAgeString(t time.Time) string {
295 return fmt.Sprintf("%.2fs ago", time.Since(t).Seconds())
298 func (cn *PeerConn) connectionFlags() (ret string) {
300 ret += string([]byte{b})
302 if cn.cryptoMethod == mse.CryptoMethodRC4 {
304 } else if cn.headerEncrypted {
307 ret += string(cn.Discovery)
314 func (cn *PeerConn) utp() bool {
315 return parseNetworkString(cn.Network).Udp
318 // Inspired by https://github.com/transmission/transmission/wiki/Peer-Status-Text.
319 func (cn *Peer) statusFlags() (ret string) {
321 ret += string([]byte{b})
323 if cn.requestState.Interested {
330 ret += cn.connectionFlags()
332 if cn.peerInterested {
341 func (cn *Peer) downloadRate() float64 {
342 num := cn._stats.BytesReadUsefulData.Int64()
346 return float64(num) / cn.totalExpectingTime().Seconds()
349 func (cn *Peer) numRequestsByPiece() (ret map[pieceIndex]int) {
350 ret = make(map[pieceIndex]int)
351 cn.requestState.Requests.Iterate(func(x uint32) bool {
352 ret[pieceIndex(x/cn.t.chunksPerRegularPiece())]++
358 func (cn *Peer) writeStatus(w io.Writer, t *Torrent) {
359 // \t isn't preserved in <pre> blocks?
360 if cn.closed.IsSet() {
361 fmt.Fprint(w, "CLOSED: ")
363 fmt.Fprintln(w, cn.connStatusString())
364 prio, err := cn.peerPriority()
365 prioStr := fmt.Sprintf("%08x", prio)
367 prioStr += ": " + err.Error()
369 fmt.Fprintf(w, " bep40-prio: %v\n", prioStr)
370 fmt.Fprintf(w, " last msg: %s, connected: %s, last helpful: %s, itime: %s, etime: %s\n",
371 eventAgeString(cn.lastMessageReceived),
372 eventAgeString(cn.completedHandshake),
373 eventAgeString(cn.lastHelpful()),
375 cn.totalExpectingTime(),
378 " %s completed, %d pieces touched, good chunks: %v/%v:%v reqq: %d+%v/(%d/%d):%d/%d, flags: %s, dr: %.1f KiB/s\n",
379 cn.completedString(),
380 len(cn.peerTouchedPieces),
381 &cn._stats.ChunksReadUseful,
382 &cn._stats.ChunksRead,
383 &cn._stats.ChunksWritten,
384 cn.requestState.Requests.GetCardinality(),
385 cn.requestState.Cancelled.GetCardinality(),
386 cn.nominalMaxRequests(),
388 len(cn.peerRequests),
391 cn.downloadRate()/(1<<10),
393 fmt.Fprintf(w, " requested pieces:")
394 type pieceNumRequestsType struct {
398 var pieceNumRequests []pieceNumRequestsType
399 for piece, count := range cn.numRequestsByPiece() {
400 pieceNumRequests = append(pieceNumRequests, pieceNumRequestsType{piece, count})
402 sort.Slice(pieceNumRequests, func(i, j int) bool {
403 return pieceNumRequests[i].piece < pieceNumRequests[j].piece
405 for _, elem := range pieceNumRequests {
406 fmt.Fprintf(w, " %v(%v)", elem.piece, elem.numRequests)
411 func (p *Peer) close() {
415 if p.updateRequestsTimer != nil {
416 p.updateRequestsTimer.Stop()
420 p.t.decPeerPieceAvailability(p)
422 for _, f := range p.callbacks.PeerClosed {
427 func (cn *PeerConn) onClose() {
428 if cn.pex.IsEnabled() {
435 if cb := cn.callbacks.PeerConnClosed; cb != nil {
440 // Peer definitely has a piece, for purposes of requesting. So it's not sufficient that we think
441 // they do (known=true).
442 func (cn *Peer) peerHasPiece(piece pieceIndex) bool {
443 if all, known := cn.peerHasAllPieces(); all && known {
446 return cn.peerPieces().ContainsInt(piece)
449 // 64KiB, but temporarily less to work around an issue with WebRTC. TODO: Update when
450 // https://github.com/pion/datachannel/issues/59 is fixed.
452 writeBufferHighWaterLen = 1 << 15
453 writeBufferLowWaterLen = writeBufferHighWaterLen / 2
456 // Writes a message into the write buffer. Returns whether it's okay to keep writing. Writing is
457 // done asynchronously, so it may be that we're not able to honour backpressure from this method.
458 func (cn *PeerConn) write(msg pp.Message) bool {
459 torrent.Add(fmt.Sprintf("messages written of type %s", msg.Type.String()), 1)
460 // We don't need to track bytes here because the connection's Writer has that behaviour injected
461 // (although there's some delay between us buffering the message, and the connection writer
462 // flushing it out.).
463 notFull := cn.messageWriter.write(msg)
464 // Last I checked only Piece messages affect stats, and we don't write those.
470 func (cn *PeerConn) requestMetadataPiece(index int) {
471 eID := cn.PeerExtensionIDs[pp.ExtensionNameMetadata]
472 if eID == pp.ExtensionDeleteNumber {
475 if index < len(cn.metadataRequests) && cn.metadataRequests[index] {
478 cn.logger.WithDefaultLevel(log.Debug).Printf("requesting metadata piece %d", index)
479 cn.write(pp.MetadataExtensionRequestMsg(eID, index))
480 for index >= len(cn.metadataRequests) {
481 cn.metadataRequests = append(cn.metadataRequests, false)
483 cn.metadataRequests[index] = true
486 func (cn *PeerConn) requestedMetadataPiece(index int) bool {
487 return index < len(cn.metadataRequests) && cn.metadataRequests[index]
491 interestedMsgLen = len(pp.Message{Type: pp.Interested}.MustMarshalBinary())
492 requestMsgLen = len(pp.Message{Type: pp.Request}.MustMarshalBinary())
493 // This is the maximum request count that could fit in the write buffer if it's at or below the
494 // low water mark when we run maybeUpdateActualRequestState.
495 maxLocalToRemoteRequests = (writeBufferHighWaterLen - writeBufferLowWaterLen - interestedMsgLen) / requestMsgLen
498 // The actual value to use as the maximum outbound requests.
499 func (cn *Peer) nominalMaxRequests() maxRequests {
500 return maxRequests(maxInt(1, minInt(cn.PeerMaxRequests, cn.peakRequests*2, maxLocalToRemoteRequests)))
503 func (cn *Peer) totalExpectingTime() (ret time.Duration) {
504 ret = cn.cumulativeExpectedToReceiveChunks
505 if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
506 ret += time.Since(cn.lastStartedExpectingToReceiveChunks)
511 func (cn *PeerConn) onPeerSentCancel(r Request) {
512 if _, ok := cn.peerRequests[r]; !ok {
513 torrent.Add("unexpected cancels received", 1)
516 if cn.fastEnabled() {
519 delete(cn.peerRequests, r)
523 func (cn *PeerConn) choke(msg messageWriter) (more bool) {
528 more = msg(pp.Message{
531 if !cn.fastEnabled() {
532 cn.peerRequests = nil
537 func (cn *PeerConn) unchoke(msg func(pp.Message) bool) bool {
542 return msg(pp.Message{
547 func (cn *Peer) setInterested(interested bool) bool {
548 if cn.requestState.Interested == interested {
551 cn.requestState.Interested = interested
553 cn.lastBecameInterested = time.Now()
554 } else if !cn.lastBecameInterested.IsZero() {
555 cn.priorInterest += time.Since(cn.lastBecameInterested)
557 cn.updateExpectingChunks()
558 // log.Printf("%p: setting interest: %v", cn, interested)
559 return cn.writeInterested(interested)
562 func (pc *PeerConn) writeInterested(interested bool) bool {
563 return pc.write(pp.Message{
564 Type: func() pp.MessageType {
568 return pp.NotInterested
574 // The function takes a message to be sent, and returns true if more messages
576 type messageWriter func(pp.Message) bool
578 // This function seems to only used by Peer.request. It's all logic checks, so maybe we can no-op it
579 // when we want to go fast.
580 func (cn *Peer) shouldRequest(r RequestIndex) error {
581 pi := cn.t.pieceIndexOfRequestIndex(r)
582 if cn.requestState.Cancelled.Contains(r) {
583 return errors.New("request is cancelled and waiting acknowledgement")
585 if !cn.peerHasPiece(pi) {
586 return errors.New("requesting piece peer doesn't have")
588 if !cn.t.peerIsActive(cn) {
589 panic("requesting but not in active conns")
591 if cn.closed.IsSet() {
592 panic("requesting when connection is closed")
594 if cn.t.hashingPiece(pi) {
595 panic("piece is being hashed")
597 if cn.t.pieceQueuedForHash(pi) {
598 panic("piece is queued for hash")
600 if cn.peerChoking && !cn.peerAllowedFast.Contains(bitmap.BitIndex(pi)) {
601 // This could occur if we made a request with the fast extension, and then got choked and
602 // haven't had the request rejected yet.
603 if !cn.requestState.Requests.Contains(r) {
604 panic("peer choking and piece not allowed fast")
610 func (cn *Peer) mustRequest(r RequestIndex) bool {
611 more, err := cn.request(r)
618 func (cn *Peer) request(r RequestIndex) (more bool, err error) {
619 if err := cn.shouldRequest(r); err != nil {
622 if cn.requestState.Requests.Contains(r) {
625 if maxRequests(cn.requestState.Requests.GetCardinality()) >= cn.nominalMaxRequests() {
626 return true, errors.New("too many outstanding requests")
628 cn.requestState.Requests.Add(r)
629 if cn.validReceiveChunks == nil {
630 cn.validReceiveChunks = make(map[RequestIndex]int)
632 cn.validReceiveChunks[r]++
633 cn.t.pendingRequests[r] = cn
634 cn.t.lastRequested[r] = time.Now()
635 cn.updateExpectingChunks()
636 ppReq := cn.t.requestIndexToRequest(r)
637 for _, f := range cn.callbacks.SentRequest {
638 f(PeerRequestEvent{cn, ppReq})
640 return cn.peerImpl._request(ppReq), nil
643 func (me *PeerConn) _request(r Request) bool {
644 return me.write(pp.Message{
652 func (me *Peer) cancel(r RequestIndex) {
653 if !me.deleteRequest(r) {
654 panic("request not existing should have been guarded")
657 if !me.requestState.Cancelled.CheckedAdd(r) {
658 panic("request already cancelled")
662 if me.isLowOnRequests() {
663 me.updateRequests("Peer.cancel")
667 func (me *PeerConn) _cancel(r RequestIndex) bool {
668 me.write(makeCancelMessage(me.t.requestIndexToRequest(r)))
669 // Transmission does not send rejects for received cancels. See
670 // https://github.com/transmission/transmission/pull/2275.
671 return me.fastEnabled() && !me.remoteIsTransmission()
674 func (cn *PeerConn) fillWriteBuffer() {
675 if cn.messageWriter.writeBuffer.Len() > writeBufferLowWaterLen {
676 // Fully committing to our max requests requires sufficient space (see
677 // maxLocalToRemoteRequests). Flush what we have instead. We also prefer always to make
678 // requests than to do PEX or upload, so we short-circuit before handling those. Any update
679 // request reason will not be cleared, so we'll come right back here when there's space. We
680 // can't do this in maybeUpdateActualRequestState because it's a method on Peer and has no
681 // knowledge of write buffers.
683 cn.maybeUpdateActualRequestState()
684 if cn.pex.IsEnabled() {
685 if flow := cn.pex.Share(cn.write); !flow {
692 func (cn *PeerConn) have(piece pieceIndex) {
693 if cn.sentHaves.Get(bitmap.BitIndex(piece)) {
698 Index: pp.Integer(piece),
700 cn.sentHaves.Add(bitmap.BitIndex(piece))
703 func (cn *PeerConn) postBitfield() {
704 if cn.sentHaves.Len() != 0 {
705 panic("bitfield must be first have-related message sent")
707 if !cn.t.haveAnyPieces() {
712 Bitfield: cn.t.bitfield(),
714 cn.sentHaves = bitmap.Bitmap{cn.t._completedPieces.Clone()}
717 // Sets a reason to update requests, and if there wasn't already one, handle it.
718 func (cn *Peer) updateRequests(reason string) {
719 if cn.needRequestUpdate != "" {
722 if reason != peerUpdateRequestsTimerReason && !cn.isLowOnRequests() {
725 cn.needRequestUpdate = reason
726 cn.handleUpdateRequests()
729 func (cn *PeerConn) handleUpdateRequests() {
730 // The writer determines the request state as needed when it can write.
734 // Emits the indices in the Bitmaps bms in order, never repeating any index.
735 // skip is mutated during execution, and its initial values will never be
737 func iterBitmapsDistinct(skip *bitmap.Bitmap, bms ...bitmap.Bitmap) iter.Func {
738 return func(cb iter.Callback) {
739 for _, bm := range bms {
741 func(_i interface{}) bool {
743 if skip.Contains(bitmap.BitIndex(i)) {
746 skip.Add(bitmap.BitIndex(i))
757 func (cn *Peer) peerPiecesChanged() {
758 cn.t.maybeDropMutuallyCompletePeer(cn)
761 func (cn *PeerConn) raisePeerMinPieces(newMin pieceIndex) {
762 if newMin > cn.peerMinPieces {
763 cn.peerMinPieces = newMin
767 func (cn *PeerConn) peerSentHave(piece pieceIndex) error {
768 if cn.t.haveInfo() && piece >= cn.t.numPieces() || piece < 0 {
769 return errors.New("invalid piece")
771 if cn.peerHasPiece(piece) {
774 cn.raisePeerMinPieces(piece + 1)
775 if !cn.peerHasPiece(piece) {
776 cn.t.incPieceAvailability(piece)
778 cn._peerPieces.Add(uint32(piece))
779 if cn.t.wantPieceIndex(piece) {
780 cn.updateRequests("have")
782 cn.peerPiecesChanged()
786 func (cn *PeerConn) peerSentBitfield(bf []bool) error {
788 panic("expected bitfield length divisible by 8")
790 // We know that the last byte means that at most the last 7 bits are wasted.
791 cn.raisePeerMinPieces(pieceIndex(len(bf) - 7))
792 if cn.t.haveInfo() && len(bf) > int(cn.t.numPieces()) {
793 // Ignore known excess pieces.
794 bf = bf[:cn.t.numPieces()]
796 bm := boolSliceToBitmap(bf)
797 if cn.t.haveInfo() && pieceIndex(bm.GetCardinality()) == cn.t.numPieces() {
798 cn.onPeerHasAllPieces()
802 cn.raisePeerMinPieces(pieceIndex(bm.Maximum()) + 1)
804 shouldUpdateRequests := false
805 if cn.peerSentHaveAll {
806 if !cn.t.deleteConnWithAllPieces(&cn.Peer) {
809 cn.peerSentHaveAll = false
810 if !cn._peerPieces.IsEmpty() {
811 panic("if peer has all, we expect no individual peer pieces to be set")
814 bm.Xor(&cn._peerPieces)
816 cn.peerSentHaveAll = false
817 // bm is now 'on' for pieces that are changing
818 bm.Iterate(func(x uint32) bool {
820 if cn._peerPieces.Contains(x) {
821 // Then we must be losing this piece
822 cn.t.decPieceAvailability(pi)
824 if !shouldUpdateRequests && cn.t.wantPieceIndex(pieceIndex(x)) {
825 shouldUpdateRequests = true
827 // We must be gaining this piece
828 cn.t.incPieceAvailability(pieceIndex(x))
832 // Apply the changes. If we had everything previously, this should be empty, so xor is the same
834 cn._peerPieces.Xor(&bm)
835 if shouldUpdateRequests {
836 cn.updateRequests("bitfield")
838 // We didn't guard this before, I see no reason to do it now.
839 cn.peerPiecesChanged()
843 func (cn *PeerConn) onPeerHasAllPieces() {
846 cn._peerPieces.Iterate(func(x uint32) bool {
847 t.decPieceAvailability(pieceIndex(x))
851 t.addConnWithAllPieces(&cn.Peer)
852 cn.peerSentHaveAll = true
853 cn._peerPieces.Clear()
854 if !cn.t._pendingPieces.IsEmpty() {
855 cn.updateRequests("Peer.onPeerHasAllPieces")
857 cn.peerPiecesChanged()
860 func (cn *PeerConn) onPeerSentHaveAll() error {
861 cn.onPeerHasAllPieces()
865 func (cn *PeerConn) peerSentHaveNone() error {
866 if cn.peerSentHaveAll {
867 cn.t.decPeerPieceAvailability(&cn.Peer)
869 cn._peerPieces.Clear()
870 cn.peerSentHaveAll = false
871 cn.peerPiecesChanged()
875 func (c *PeerConn) requestPendingMetadata() {
879 if c.PeerExtensionIDs[pp.ExtensionNameMetadata] == 0 {
880 // Peer doesn't support this.
883 // Request metadata pieces that we don't have in a random order.
885 for index := 0; index < c.t.metadataPieceCount(); index++ {
886 if !c.t.haveMetadataPiece(index) && !c.requestedMetadataPiece(index) {
887 pending = append(pending, index)
890 rand.Shuffle(len(pending), func(i, j int) { pending[i], pending[j] = pending[j], pending[i] })
891 for _, i := range pending {
892 c.requestMetadataPiece(i)
896 func (cn *PeerConn) wroteMsg(msg *pp.Message) {
897 torrent.Add(fmt.Sprintf("messages written of type %s", msg.Type.String()), 1)
898 if msg.Type == pp.Extended {
899 for name, id := range cn.PeerExtensionIDs {
900 if id != msg.ExtendedID {
903 torrent.Add(fmt.Sprintf("Extended messages written for protocol %q", name), 1)
906 cn.allStats(func(cs *ConnStats) { cs.wroteMsg(msg) })
909 // After handshake, we know what Torrent and Client stats to include for a
911 func (cn *Peer) postHandshakeStats(f func(*ConnStats)) {
917 // All ConnStats that include this connection. Some objects are not known
918 // until the handshake is complete, after which it's expected to reconcile the
920 func (cn *Peer) allStats(f func(*ConnStats)) {
922 if cn.reconciledHandshakeStats {
923 cn.postHandshakeStats(f)
927 func (cn *PeerConn) wroteBytes(n int64) {
928 cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesWritten }))
931 func (cn *Peer) readBytes(n int64) {
932 cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesRead }))
935 // Returns whether the connection could be useful to us. We're seeding and
936 // they want data, we don't have metainfo and they can provide it, etc.
937 func (c *Peer) useful() bool {
939 if c.closed.IsSet() {
943 return c.supportsExtension("ut_metadata")
945 if t.seeding() && c.peerInterested {
948 if c.peerHasWantedPieces() {
954 func (c *Peer) lastHelpful() (ret time.Time) {
955 ret = c.lastUsefulChunkReceived
956 if c.t.seeding() && c.lastChunkSent.After(ret) {
957 ret = c.lastChunkSent
962 func (c *PeerConn) fastEnabled() bool {
963 return c.PeerExtensionBytes.SupportsFast() && c.t.cl.config.Extensions.SupportsFast()
966 func (c *PeerConn) reject(r Request) {
967 if !c.fastEnabled() {
968 panic("fast not enabled")
970 c.write(r.ToMsg(pp.Reject))
971 delete(c.peerRequests, r)
974 func (c *PeerConn) onReadRequest(r Request) error {
975 requestedChunkLengths.Add(strconv.FormatUint(r.Length.Uint64(), 10), 1)
976 if _, ok := c.peerRequests[r]; ok {
977 torrent.Add("duplicate requests received", 1)
981 torrent.Add("requests received while choking", 1)
983 torrent.Add("requests rejected while choking", 1)
988 // TODO: What if they've already requested this?
989 if len(c.peerRequests) >= localClientReqq {
990 torrent.Add("requests received while queue full", 1)
994 // BEP 6 says we may close here if we choose.
997 if !c.t.havePiece(pieceIndex(r.Index)) {
998 // This isn't necessarily them screwing up. We can drop pieces
999 // from our storage, and can't communicate this to peers
1000 // except by reconnecting.
1001 requestsReceivedForMissingPieces.Add(1)
1002 return fmt.Errorf("peer requested piece we don't have: %v", r.Index.Int())
1004 // Check this after we know we have the piece, so that the piece length will be known.
1005 if r.Begin+r.Length > c.t.pieceLength(pieceIndex(r.Index)) {
1006 torrent.Add("bad requests received", 1)
1007 return errors.New("bad Request")
1009 if c.peerRequests == nil {
1010 c.peerRequests = make(map[Request]*peerRequestState, localClientReqq)
1012 value := &peerRequestState{}
1013 c.peerRequests[r] = value
1014 go c.peerRequestDataReader(r, value)
1018 func (c *PeerConn) peerRequestDataReader(r Request, prs *peerRequestState) {
1019 b, err := readPeerRequestData(r, c)
1021 defer c.locker().Unlock()
1023 c.peerRequestDataReadFailed(err, r)
1026 panic("data must be non-nil to trigger send")
1028 torrent.Add("peer request data read successes", 1)
1034 // If this is maintained correctly, we might be able to support optional synchronous reading for
1035 // chunk sending, the way it used to work.
1036 func (c *PeerConn) peerRequestDataReadFailed(err error, r Request) {
1037 torrent.Add("peer request data read failures", 1)
1038 logLevel := log.Warning
1039 if c.t.hasStorageCap() {
1040 // It's expected that pieces might drop. See
1041 // https://github.com/anacrolix/torrent/issues/702#issuecomment-1000953313.
1042 logLevel = log.Debug
1044 c.logger.WithDefaultLevel(logLevel).Printf("error reading chunk for peer Request %v: %v", r, err)
1045 if c.t.closed.IsSet() {
1048 i := pieceIndex(r.Index)
1049 if c.t.pieceComplete(i) {
1050 // There used to be more code here that just duplicated the following break. Piece
1051 // completions are currently cached, so I'm not sure how helpful this update is, except to
1052 // pull any completion changes pushed to the storage backend in failed reads that got us
1054 c.t.updatePieceCompletion(i)
1056 // We've probably dropped a piece from storage, but there's no way to communicate this to the
1057 // peer. If they ask for it again, we kick them allowing us to send them updated piece states if
1058 // we reconnect. TODO: Instead, we could just try to update them with Bitfield or HaveNone and
1059 // if they kick us for breaking protocol, on reconnect we will be compliant again (at least
1061 if c.fastEnabled() {
1065 // If fast isn't enabled, I think we would have wiped all peer requests when we last
1066 // choked, and requests while we're choking would be ignored. It could be possible that
1067 // a peer request data read completed concurrently to it being deleted elsewhere.
1068 c.logger.WithDefaultLevel(log.Warning).Printf("already choking peer, requests might not be rejected correctly")
1070 // Choking a non-fast peer should cause them to flush all their requests.
1075 func readPeerRequestData(r Request, c *PeerConn) ([]byte, error) {
1076 b := make([]byte, r.Length)
1077 p := c.t.info.Piece(int(r.Index))
1078 n, err := c.t.readAt(b, p.Offset()+int64(r.Begin))
1085 panic("expected error")
1091 func runSafeExtraneous(f func()) {
1099 func (c *PeerConn) logProtocolBehaviour(level log.Level, format string, arg ...interface{}) {
1100 c.logger.WithContextText(fmt.Sprintf(
1101 "peer id %q, ext v %q", c.PeerID, c.PeerClientName.Load(),
1102 )).SkipCallers(1).Levelf(level, format, arg...)
1105 // Processes incoming BitTorrent wire-protocol messages. The client lock is held upon entry and
1106 // exit. Returning will end the connection.
1107 func (c *PeerConn) mainReadLoop() (err error) {
1110 torrent.Add("connection.mainReadLoop returned with error", 1)
1112 torrent.Add("connection.mainReadLoop returned with no error", 1)
1118 decoder := pp.Decoder{
1119 R: bufio.NewReaderSize(c.r, 1<<17),
1120 MaxLength: 4 * pp.Integer(max(int64(t.chunkSize), defaultChunkSize)),
1128 err = decoder.Decode(&msg)
1130 if cb := c.callbacks.ReadMessage; cb != nil && err == nil {
1133 if t.closed.IsSet() || c.closed.IsSet() {
1139 c.lastMessageReceived = time.Now()
1141 receivedKeepalives.Add(1)
1144 messageTypesReceived.Add(msg.Type.String(), 1)
1145 if msg.Type.FastExtension() && !c.fastEnabled() {
1146 runSafeExtraneous(func() { torrent.Add("fast messages received when extension is disabled", 1) })
1147 return fmt.Errorf("received fast extension message (type=%v) but extension is disabled", msg.Type)
1154 if !c.fastEnabled() {
1155 if !c.deleteAllRequests().IsEmpty() {
1156 c.t.iterPeers(func(p *Peer) {
1157 if p.isLowOnRequests() {
1158 p.updateRequests("choked by non-fast PeerConn")
1163 // We don't decrement pending requests here, let's wait for the peer to either
1164 // reject or satisfy the outstanding requests. Additionally, some peers may unchoke
1165 // us and resume where they left off, we don't want to have piled on to those chunks
1166 // in the meanwhile. I think a peer's ability to abuse this should be limited: they
1167 // could let us request a lot of stuff, then choke us and never reject, but they're
1168 // only a single peer, our chunk balancing should smooth over this abuse.
1170 c.peerChoking = true
1171 c.updateExpectingChunks()
1174 // Some clients do this for some reason. Transmission doesn't error on this, so we
1175 // won't for consistency.
1176 c.logProtocolBehaviour(log.Debug, "received unchoke when already unchoked")
1179 c.peerChoking = false
1181 c.requestState.Requests.Iterate(func(x uint32) bool {
1182 if !c.peerAllowedFast.Contains(x / c.t.chunksPerRegularPiece()) {
1187 if preservedCount != 0 {
1188 // TODO: Yes this is a debug log but I'm not happy with the state of the logging lib
1190 c.logger.Levelf(log.Debug,
1191 "%v requests were preserved while being choked (fast=%v)",
1195 torrent.Add("requestsPreservedThroughChoking", int64(preservedCount))
1197 if !c.t._pendingPieces.IsEmpty() {
1198 c.updateRequests("unchoked")
1200 c.updateExpectingChunks()
1202 c.peerInterested = true
1204 case pp.NotInterested:
1205 c.peerInterested = false
1206 // We don't clear their requests since it isn't clear in the spec.
1207 // We'll probably choke them for this, which will clear them if
1208 // appropriate, and is clearly specified.
1210 err = c.peerSentHave(pieceIndex(msg.Index))
1212 err = c.peerSentBitfield(msg.Bitfield)
1214 r := newRequestFromMessage(&msg)
1215 err = c.onReadRequest(r)
1217 c.doChunkReadStats(int64(len(msg.Piece)))
1218 err = c.receiveChunk(&msg)
1219 if len(msg.Piece) == int(t.chunkSize) {
1220 t.chunkPool.Put(&msg.Piece)
1223 err = fmt.Errorf("receiving chunk: %w", err)
1226 req := newRequestFromMessage(&msg)
1227 c.onPeerSentCancel(req)
1229 ipa, ok := tryIpPortFromNetAddr(c.RemoteAddr)
1233 pingAddr := net.UDPAddr{
1238 pingAddr.Port = int(msg.Port)
1240 cl.eachDhtServer(func(s DhtServer) {
1241 go s.Ping(&pingAddr)
1244 torrent.Add("suggests received", 1)
1245 log.Fmsg("peer suggested piece %d", msg.Index).AddValues(c, msg.Index).LogLevel(log.Debug, c.t.logger)
1246 c.updateRequests("suggested")
1248 err = c.onPeerSentHaveAll()
1250 err = c.peerSentHaveNone()
1252 req := newRequestFromMessage(&msg)
1253 if !c.remoteRejectedRequest(c.t.requestIndexFromRequest(req)) {
1254 c.logger.Printf("received invalid reject [request=%v, peer=%v]", req, c)
1255 err = fmt.Errorf("received invalid reject [request=%v]", req)
1257 case pp.AllowedFast:
1258 torrent.Add("allowed fasts received", 1)
1259 log.Fmsg("peer allowed fast: %d", msg.Index).AddValues(c).LogLevel(log.Debug, c.t.logger)
1260 c.updateRequests("PeerConn.mainReadLoop allowed fast")
1262 err = c.onReadExtendedMsg(msg.ExtendedID, msg.ExtendedPayload)
1264 err = fmt.Errorf("received unknown message type: %#v", msg.Type)
1272 // Returns true if it was valid to reject the request.
1273 func (c *Peer) remoteRejectedRequest(r RequestIndex) bool {
1274 if c.deleteRequest(r) {
1276 } else if !c.requestState.Cancelled.CheckedRemove(r) {
1279 if c.isLowOnRequests() {
1280 c.updateRequests("Peer.remoteRejectedRequest")
1282 c.decExpectedChunkReceive(r)
1286 func (c *Peer) decExpectedChunkReceive(r RequestIndex) {
1287 count := c.validReceiveChunks[r]
1289 delete(c.validReceiveChunks, r)
1290 } else if count > 1 {
1291 c.validReceiveChunks[r] = count - 1
1297 func (c *PeerConn) onReadExtendedMsg(id pp.ExtensionNumber, payload []byte) (err error) {
1299 // TODO: Should we still do this?
1301 // These clients use their own extension IDs for outgoing message
1302 // types, which is incorrect.
1303 if bytes.HasPrefix(c.PeerID[:], []byte("-SD0100-")) || strings.HasPrefix(string(c.PeerID[:]), "-XL0012-") {
1311 case pp.HandshakeExtendedID:
1312 var d pp.ExtendedHandshakeMessage
1313 if err := bencode.Unmarshal(payload, &d); err != nil {
1314 c.logger.Printf("error parsing extended handshake message %q: %s", payload, err)
1315 return fmt.Errorf("unmarshalling extended handshake payload: %w", err)
1317 if cb := c.callbacks.ReadExtendedHandshake; cb != nil {
1320 // c.logger.WithDefaultLevel(log.Debug).Printf("received extended handshake message:\n%s", spew.Sdump(d))
1322 c.PeerMaxRequests = d.Reqq
1324 c.PeerClientName.Store(d.V)
1325 if c.PeerExtensionIDs == nil {
1326 c.PeerExtensionIDs = make(map[pp.ExtensionName]pp.ExtensionNumber, len(d.M))
1328 c.PeerListenPort = d.Port
1329 c.PeerPrefersEncryption = d.Encryption
1330 for name, id := range d.M {
1331 if _, ok := c.PeerExtensionIDs[name]; !ok {
1332 peersSupportingExtension.Add(
1333 // expvar.Var.String must produce valid JSON. "ut_payme\xeet_address" was being
1334 // entered here which caused problems later when unmarshalling.
1335 strconv.Quote(string(name)),
1338 c.PeerExtensionIDs[name] = id
1340 if d.MetadataSize != 0 {
1341 if err = t.setMetadataSize(d.MetadataSize); err != nil {
1342 return fmt.Errorf("setting metadata size to %d: %w", d.MetadataSize, err)
1345 c.requestPendingMetadata()
1346 if !t.cl.config.DisablePEX {
1347 t.pex.Add(c) // we learnt enough now
1351 case metadataExtendedId:
1352 err := cl.gotMetadataExtensionMsg(payload, t, c)
1354 return fmt.Errorf("handling metadata extension message: %w", err)
1358 if !c.pex.IsEnabled() {
1359 return nil // or hang-up maybe?
1361 return c.pex.Recv(payload)
1363 return fmt.Errorf("unexpected extended message ID: %v", id)
1367 // Set both the Reader and Writer for the connection from a single ReadWriter.
1368 func (cn *PeerConn) setRW(rw io.ReadWriter) {
1373 // Returns the Reader and Writer as a combined ReadWriter.
1374 func (cn *PeerConn) rw() io.ReadWriter {
1381 func (c *Peer) doChunkReadStats(size int64) {
1382 c.allStats(func(cs *ConnStats) { cs.receivedChunk(size) })
1385 // Handle a received chunk from a peer.
1386 func (c *Peer) receiveChunk(msg *pp.Message) error {
1387 chunksReceived.Add("total", 1)
1389 ppReq := newRequestFromMessage(msg)
1390 req := c.t.requestIndexFromRequest(ppReq)
1393 if c.bannableAddr.Ok() {
1394 t.smartBanCache.RecordBlock(c.bannableAddr.Value(), req, msg.Piece)
1398 chunksReceived.Add("while choked", 1)
1401 if c.validReceiveChunks[req] <= 0 {
1402 chunksReceived.Add("unexpected", 1)
1403 return errors.New("received unexpected chunk")
1405 c.decExpectedChunkReceive(req)
1407 if c.peerChoking && c.peerAllowedFast.Contains(bitmap.BitIndex(ppReq.Index)) {
1408 chunksReceived.Add("due to allowed fast", 1)
1411 // The request needs to be deleted immediately to prevent cancels occurring asynchronously when
1412 // have actually already received the piece, while we have the Client unlocked to write the data
1416 if c.requestState.Requests.Contains(req) {
1417 for _, f := range c.callbacks.ReceivedRequested {
1418 f(PeerMessageEvent{c, msg})
1421 // Request has been satisfied.
1422 if c.deleteRequest(req) || c.requestState.Cancelled.CheckedRemove(req) {
1425 c._chunksReceivedWhileExpecting++
1427 if c.isLowOnRequests() {
1428 c.updateRequests("Peer.receiveChunk deleted request")
1431 chunksReceived.Add("unintended", 1)
1437 // Do we actually want this chunk?
1438 if t.haveChunk(ppReq) {
1439 // panic(fmt.Sprintf("%+v", ppReq))
1440 chunksReceived.Add("redundant", 1)
1441 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadWasted }))
1445 piece := &t.pieces[ppReq.Index]
1447 c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadUseful }))
1448 c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulData }))
1450 c.piecesReceivedSinceLastRequestUpdate++
1451 c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulIntendedData }))
1453 for _, f := range c.t.cl.config.Callbacks.ReceivedUsefulData {
1454 f(ReceivedUsefulDataEvent{c, msg})
1456 c.lastUsefulChunkReceived = time.Now()
1458 // Need to record that it hasn't been written yet, before we attempt to do
1459 // anything with it.
1460 piece.incrementPendingWrites()
1461 // Record that we have the chunk, so we aren't trying to download it while
1462 // waiting for it to be written to storage.
1463 piece.unpendChunkIndex(chunkIndexFromChunkSpec(ppReq.ChunkSpec, t.chunkSize))
1465 // Cancel pending requests for this chunk from *other* peers.
1466 if p := t.pendingRequests[req]; p != nil {
1468 panic("should not be pending request from conn that just received it")
1473 err := func() error {
1476 concurrentChunkWrites.Add(1)
1477 defer concurrentChunkWrites.Add(-1)
1478 // Write the chunk out. Note that the upper bound on chunk writing concurrency will be the
1479 // number of connections. We write inline with receiving the chunk (with this lock dance),
1480 // because we want to handle errors synchronously and I haven't thought of a nice way to
1481 // defer any concurrency to the storage and have that notify the client of errors. TODO: Do
1483 return t.writeChunk(int(msg.Index), int64(msg.Begin), msg.Piece)
1486 piece.decrementPendingWrites()
1489 c.logger.WithDefaultLevel(log.Error).Printf("writing received chunk %v: %v", req, err)
1491 // Necessary to pass TestReceiveChunkStorageFailureSeederFastExtensionDisabled. I think a
1492 // request update runs while we're writing the chunk that just failed. Then we never do a
1493 // fresh update after pending the failed request.
1494 c.updateRequests("Peer.receiveChunk error writing chunk")
1495 t.onWriteChunkErr(err)
1499 c.onDirtiedPiece(pieceIndex(ppReq.Index))
1501 // We need to ensure the piece is only queued once, so only the last chunk writer gets this job.
1502 if t.pieceAllDirty(pieceIndex(ppReq.Index)) && piece.pendingWrites == 0 {
1503 t.queuePieceCheck(pieceIndex(ppReq.Index))
1504 // We don't pend all chunks here anymore because we don't want code dependent on the dirty
1505 // chunk status (such as the haveChunk call above) to have to check all the various other
1506 // piece states like queued for hash, hashing etc. This does mean that we need to be sure
1507 // that chunk pieces are pended at an appropriate time later however.
1510 cl.event.Broadcast()
1511 // We do this because we've written a chunk, and may change PieceState.Partial.
1512 t.publishPieceChange(pieceIndex(ppReq.Index))
1517 func (c *Peer) onDirtiedPiece(piece pieceIndex) {
1518 if c.peerTouchedPieces == nil {
1519 c.peerTouchedPieces = make(map[pieceIndex]struct{})
1521 c.peerTouchedPieces[piece] = struct{}{}
1522 ds := &c.t.pieces[piece].dirtiers
1524 *ds = make(map[*Peer]struct{})
1526 (*ds)[c] = struct{}{}
1529 func (c *PeerConn) uploadAllowed() bool {
1530 if c.t.cl.config.NoUpload {
1533 if c.t.dataUploadDisallowed {
1539 if !c.peerHasWantedPieces() {
1542 // Don't upload more than 100 KiB more than we download.
1543 if c._stats.BytesWrittenData.Int64() >= c._stats.BytesReadData.Int64()+100<<10 {
1549 func (c *PeerConn) setRetryUploadTimer(delay time.Duration) {
1550 if c.uploadTimer == nil {
1551 c.uploadTimer = time.AfterFunc(delay, c.tickleWriter)
1553 c.uploadTimer.Reset(delay)
1557 // Also handles choking and unchoking of the remote peer.
1558 func (c *PeerConn) upload(msg func(pp.Message) bool) bool {
1559 // Breaking or completing this loop means we don't want to upload to the
1560 // peer anymore, and we choke them.
1562 for c.uploadAllowed() {
1563 // We want to upload to the peer.
1564 if !c.unchoke(msg) {
1567 for r, state := range c.peerRequests {
1568 if state.data == nil {
1571 res := c.t.cl.config.UploadRateLimiter.ReserveN(time.Now(), int(r.Length))
1573 panic(fmt.Sprintf("upload rate limiter burst size < %d", r.Length))
1575 delay := res.Delay()
1578 c.setRetryUploadTimer(delay)
1579 // Hard to say what to return here.
1582 more := c.sendChunk(r, msg, state)
1583 delete(c.peerRequests, r)
1594 func (cn *PeerConn) drop() {
1595 cn.t.dropConnection(cn)
1598 func (cn *PeerConn) ban() {
1599 cn.t.cl.banPeerIP(cn.remoteIp())
1602 func (cn *Peer) netGoodPiecesDirtied() int64 {
1603 return cn._stats.PiecesDirtiedGood.Int64() - cn._stats.PiecesDirtiedBad.Int64()
1606 func (c *Peer) peerHasWantedPieces() bool {
1607 if all, _ := c.peerHasAllPieces(); all {
1608 return !c.t.haveAllPieces() && !c.t._pendingPieces.IsEmpty()
1610 if !c.t.haveInfo() {
1611 return !c.peerPieces().IsEmpty()
1613 return c.peerPieces().Intersects(&c.t._pendingPieces)
1616 // Returns true if an outstanding request is removed. Cancelled requests should be handled
1618 func (c *Peer) deleteRequest(r RequestIndex) bool {
1619 if !c.requestState.Requests.CheckedRemove(r) {
1622 for _, f := range c.callbacks.DeletedRequest {
1623 f(PeerRequestEvent{c, c.t.requestIndexToRequest(r)})
1625 c.updateExpectingChunks()
1626 if c.t.requestingPeer(r) != c {
1627 panic("only one peer should have a given request at a time")
1629 delete(c.t.pendingRequests, r)
1630 delete(c.t.lastRequested, r)
1631 // c.t.iterPeers(func(p *Peer) {
1632 // if p.isLowOnRequests() {
1633 // p.updateRequests("Peer.deleteRequest")
1639 func (c *Peer) deleteAllRequests() (deleted *roaring.Bitmap) {
1640 deleted = c.requestState.Requests.Clone()
1641 deleted.Iterate(func(x uint32) bool {
1642 if !c.deleteRequest(x) {
1643 panic("request should exist")
1647 c.assertNoRequests()
1651 func (c *Peer) assertNoRequests() {
1652 if !c.requestState.Requests.IsEmpty() {
1653 panic(c.requestState.Requests.GetCardinality())
1657 func (c *Peer) cancelAllRequests() (cancelled *roaring.Bitmap) {
1658 cancelled = c.requestState.Requests.Clone()
1659 cancelled.Iterate(func(x uint32) bool {
1663 c.assertNoRequests()
1667 // This is called when something has changed that should wake the writer, such as putting stuff into
1668 // the writeBuffer, or changing some state that the writer can act on.
1669 func (c *PeerConn) tickleWriter() {
1670 c.messageWriter.writeCond.Broadcast()
1673 func (c *PeerConn) sendChunk(r Request, msg func(pp.Message) bool, state *peerRequestState) (more bool) {
1674 c.lastChunkSent = time.Now()
1675 return msg(pp.Message{
1683 func (c *PeerConn) setTorrent(t *Torrent) {
1685 panic("connection already associated with a torrent")
1688 c.logger.WithDefaultLevel(log.Debug).Printf("set torrent=%v", t)
1689 t.reconcileHandshakeStats(c)
1692 func (c *Peer) peerPriority() (peerPriority, error) {
1693 return bep40Priority(c.remoteIpPort(), c.t.cl.publicAddr(c.remoteIp()))
1696 func (c *Peer) remoteIp() net.IP {
1697 host, _, _ := net.SplitHostPort(c.RemoteAddr.String())
1698 return net.ParseIP(host)
1701 func (c *Peer) remoteIpPort() IpPort {
1702 ipa, _ := tryIpPortFromNetAddr(c.RemoteAddr)
1703 return IpPort{ipa.IP, uint16(ipa.Port)}
1706 func (c *PeerConn) pexPeerFlags() pp.PexPeerFlags {
1707 f := pp.PexPeerFlags(0)
1708 if c.PeerPrefersEncryption {
1709 f |= pp.PexPrefersEncryption
1712 f |= pp.PexOutgoingConn
1715 f |= pp.PexSupportsUtp
1720 // This returns the address to use if we want to dial the peer again. It incorporates the peer's
1721 // advertised listen port.
1722 func (c *PeerConn) dialAddr() PeerRemoteAddr {
1723 if !c.outgoing && c.PeerListenPort != 0 {
1724 switch addr := c.RemoteAddr.(type) {
1727 dialAddr.Port = c.PeerListenPort
1731 dialAddr.Port = c.PeerListenPort
1738 func (c *PeerConn) pexEvent(t pexEventType) pexEvent {
1739 f := c.pexPeerFlags()
1740 addr := c.dialAddr()
1741 return pexEvent{t, addr, f, nil}
1744 func (c *PeerConn) String() string {
1745 return fmt.Sprintf("%T %p [id=%q, exts=%v, v=%q]", c, c, c.PeerID, c.PeerExtensionBytes, c.PeerClientName.Load())
1748 func (c *Peer) trust() connectionTrust {
1749 return connectionTrust{c.trusted, c.netGoodPiecesDirtied()}
1752 type connectionTrust struct {
1754 NetGoodPiecesDirted int64
1757 func (l connectionTrust) Less(r connectionTrust) bool {
1758 return multiless.New().Bool(l.Implicit, r.Implicit).Int64(l.NetGoodPiecesDirted, r.NetGoodPiecesDirted).Less()
1761 // Returns the pieces the peer could have based on their claims. If we don't know how many pieces
1762 // are in the torrent, it could be a very large range the peer has sent HaveAll.
1763 func (cn *PeerConn) PeerPieces() *roaring.Bitmap {
1765 defer cn.locker().RUnlock()
1766 return cn.newPeerPieces()
1769 // Returns a new Bitmap that includes bits for all pieces the peer could have based on their claims.
1770 func (cn *Peer) newPeerPieces() *roaring.Bitmap {
1771 // TODO: Can we use copy on write?
1772 ret := cn.peerPieces().Clone()
1773 if all, _ := cn.peerHasAllPieces(); all {
1774 if cn.t.haveInfo() {
1775 ret.AddRange(0, bitmap.BitRange(cn.t.numPieces()))
1777 ret.AddRange(0, bitmap.ToEnd)
1783 func (cn *Peer) stats() *ConnStats {
1787 func (p *Peer) TryAsPeerConn() (*PeerConn, bool) {
1788 pc, ok := p.peerImpl.(*PeerConn)
1792 func (p *Peer) uncancelledRequests() uint64 {
1793 return p.requestState.Requests.GetCardinality()
1796 func (pc *PeerConn) remoteIsTransmission() bool {
1797 return bytes.HasPrefix(pc.PeerID[:], []byte("-TR")) && pc.PeerID[7] == '-'