package torrent
+import (
+ "errors"
+ "fmt"
+ "io"
+ "net"
+ "strings"
+ "sync/atomic"
+ "time"
+
+ "github.com/RoaringBitmap/roaring"
+ "github.com/anacrolix/chansync"
+ . "github.com/anacrolix/generics"
+ "github.com/anacrolix/log"
+ "github.com/anacrolix/missinggo/iter"
+ "github.com/anacrolix/missinggo/v2/bitmap"
+ "github.com/anacrolix/multiless"
+
+ "github.com/anacrolix/torrent/internal/alloclim"
+ "github.com/anacrolix/torrent/mse"
+ pp "github.com/anacrolix/torrent/peer_protocol"
+ request_strategy "github.com/anacrolix/torrent/request-strategy"
+ "github.com/anacrolix/torrent/typed-roaring"
+)
+
+type (
+ Peer struct {
+ // First to ensure 64-bit alignment for atomics. See #262.
+ _stats ConnStats
+
+ t *Torrent
+
+ peerImpl
+ callbacks *Callbacks
+
+ outgoing bool
+ Network string
+ RemoteAddr PeerRemoteAddr
+ // The local address as observed by the remote peer. WebRTC seems to get this right without needing hints from the
+ // config.
+ localPublicAddr peerLocalPublicAddr
+ bannableAddr Option[bannableAddr]
+ // True if the connection is operating over MSE obfuscation.
+ headerEncrypted bool
+ cryptoMethod mse.CryptoMethod
+ Discovery PeerSource
+ trusted bool
+ closed chansync.SetOnce
+ // Set true after we've added our ConnStats generated during handshake to
+ // other ConnStat instances as determined when the *Torrent became known.
+ reconciledHandshakeStats bool
+
+ lastMessageReceived time.Time
+ completedHandshake time.Time
+ lastUsefulChunkReceived time.Time
+ lastChunkSent time.Time
+
+ // Stuff controlled by the local peer.
+ needRequestUpdate string
+ requestState request_strategy.PeerRequestState
+ updateRequestsTimer *time.Timer
+ lastRequestUpdate time.Time
+ peakRequests maxRequests
+ lastBecameInterested time.Time
+ priorInterest time.Duration
+
+ lastStartedExpectingToReceiveChunks time.Time
+ cumulativeExpectedToReceiveChunks time.Duration
+ _chunksReceivedWhileExpecting int64
+
+ choking bool
+ piecesReceivedSinceLastRequestUpdate maxRequests
+ maxPiecesReceivedBetweenRequestUpdates maxRequests
+ // Chunks that we might reasonably expect to receive from the peer. Due to latency, buffering,
+ // and implementation differences, we may receive chunks that are no longer in the set of
+ // requests actually want. This could use a roaring.BSI if the memory use becomes noticeable.
+ validReceiveChunks map[RequestIndex]int
+ // Indexed by metadata piece, set to true if posted and pending a
+ // response.
+ metadataRequests []bool
+ sentHaves bitmap.Bitmap
+
+ // Stuff controlled by the remote peer.
+ peerInterested bool
+ peerChoking bool
+ peerRequests map[Request]*peerRequestState
+ PeerPrefersEncryption bool // as indicated by 'e' field in extension handshake
+ PeerListenPort int
+ // The highest possible number of pieces the torrent could have based on
+ // communication with the peer. Generally only useful until we have the
+ // torrent info.
+ peerMinPieces pieceIndex
+ // Pieces we've accepted chunks for from the peer.
+ peerTouchedPieces map[pieceIndex]struct{}
+ peerAllowedFast typedRoaring.Bitmap[pieceIndex]
+
+ PeerMaxRequests maxRequests // Maximum pending requests the peer allows.
+ PeerExtensionIDs map[pp.ExtensionName]pp.ExtensionNumber
+ PeerClientName atomic.Value
+
+ logger log.Logger
+ }
+
+ PeerSource string
+
+ peerRequestState struct {
+ data []byte
+ allocReservation *alloclim.Reservation
+ }
+
+ PeerRemoteAddr interface {
+ String() string
+ }
+
+ peerRequests = orderedBitmap[RequestIndex]
+)
+
+const (
+ PeerSourceTracker = "Tr"
+ PeerSourceIncoming = "I"
+ PeerSourceDhtGetPeers = "Hg" // Peers we found by searching a DHT.
+ PeerSourceDhtAnnouncePeer = "Ha" // Peers that were announced to us by a DHT.
+ PeerSourcePex = "X"
+ // The peer was given directly, such as through a magnet link.
+ PeerSourceDirect = "M"
+)
+
+func (p *Peer) initRequestState() {
+ p.requestState.Requests = &peerRequests{}
+}
+
+func (cn *Peer) updateExpectingChunks() {
+ if cn.expectingChunks() {
+ if cn.lastStartedExpectingToReceiveChunks.IsZero() {
+ cn.lastStartedExpectingToReceiveChunks = time.Now()
+ }
+ } else {
+ if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
+ cn.cumulativeExpectedToReceiveChunks += time.Since(cn.lastStartedExpectingToReceiveChunks)
+ cn.lastStartedExpectingToReceiveChunks = time.Time{}
+ }
+ }
+}
+
+func (cn *Peer) expectingChunks() bool {
+ if cn.requestState.Requests.IsEmpty() {
+ return false
+ }
+ if !cn.requestState.Interested {
+ return false
+ }
+ if !cn.peerChoking {
+ return true
+ }
+ haveAllowedFastRequests := false
+ cn.peerAllowedFast.Iterate(func(i pieceIndex) bool {
+ haveAllowedFastRequests = roaringBitmapRangeCardinality[RequestIndex](
+ cn.requestState.Requests,
+ cn.t.pieceRequestIndexOffset(i),
+ cn.t.pieceRequestIndexOffset(i+1),
+ ) == 0
+ return !haveAllowedFastRequests
+ })
+ return haveAllowedFastRequests
+}
+
+func (cn *Peer) remoteChokingPiece(piece pieceIndex) bool {
+ return cn.peerChoking && !cn.peerAllowedFast.Contains(piece)
+}
+
+func (cn *Peer) cumInterest() time.Duration {
+ ret := cn.priorInterest
+ if cn.requestState.Interested {
+ ret += time.Since(cn.lastBecameInterested)
+ }
+ return ret
+}
+
+func (cn *Peer) locker() *lockWithDeferreds {
+ return cn.t.cl.locker()
+}
+
+func (cn *Peer) supportsExtension(ext pp.ExtensionName) bool {
+ _, ok := cn.PeerExtensionIDs[ext]
+ return ok
+}
+
+// The best guess at number of pieces in the torrent for this peer.
+func (cn *Peer) bestPeerNumPieces() pieceIndex {
+ if cn.t.haveInfo() {
+ return cn.t.numPieces()
+ }
+ return cn.peerMinPieces
+}
+
+func (cn *Peer) completedString() string {
+ have := pieceIndex(cn.peerPieces().GetCardinality())
+ if all, _ := cn.peerHasAllPieces(); all {
+ have = cn.bestPeerNumPieces()
+ }
+ return fmt.Sprintf("%d/%d", have, cn.bestPeerNumPieces())
+}
+
+func eventAgeString(t time.Time) string {
+ if t.IsZero() {
+ return "never"
+ }
+ return fmt.Sprintf("%.2fs ago", time.Since(t).Seconds())
+}
+
+// Inspired by https://github.com/transmission/transmission/wiki/Peer-Status-Text.
+func (cn *Peer) statusFlags() (ret string) {
+ c := func(b byte) {
+ ret += string([]byte{b})
+ }
+ if cn.requestState.Interested {
+ c('i')
+ }
+ if cn.choking {
+ c('c')
+ }
+ c('-')
+ ret += cn.connectionFlags()
+ c('-')
+ if cn.peerInterested {
+ c('i')
+ }
+ if cn.peerChoking {
+ c('c')
+ }
+ return
+}
+
+func (cn *Peer) downloadRate() float64 {
+ num := cn._stats.BytesReadUsefulData.Int64()
+ if num == 0 {
+ return 0
+ }
+ return float64(num) / cn.totalExpectingTime().Seconds()
+}
+
+func (cn *Peer) DownloadRate() float64 {
+ cn.locker().RLock()
+ defer cn.locker().RUnlock()
+
+ return cn.downloadRate()
+}
+
+func (cn *Peer) iterContiguousPieceRequests(f func(piece pieceIndex, count int)) {
+ var last Option[pieceIndex]
+ var count int
+ next := func(item Option[pieceIndex]) {
+ if item == last {
+ count++
+ } else {
+ if count != 0 {
+ f(last.Value, count)
+ }
+ last = item
+ count = 1
+ }
+ }
+ cn.requestState.Requests.Iterate(func(requestIndex request_strategy.RequestIndex) bool {
+ next(Some(cn.t.pieceIndexOfRequestIndex(requestIndex)))
+ return true
+ })
+ next(None[pieceIndex]())
+}
+
+func (cn *Peer) writeStatus(w io.Writer, t *Torrent) {
+ // \t isn't preserved in <pre> blocks?
+ if cn.closed.IsSet() {
+ fmt.Fprint(w, "CLOSED: ")
+ }
+ fmt.Fprintln(w, strings.Join(cn.peerImplStatusLines(), "\n"))
+ prio, err := cn.peerPriority()
+ prioStr := fmt.Sprintf("%08x", prio)
+ if err != nil {
+ prioStr += ": " + err.Error()
+ }
+ fmt.Fprintf(w, "bep40-prio: %v\n", prioStr)
+ fmt.Fprintf(w, "last msg: %s, connected: %s, last helpful: %s, itime: %s, etime: %s\n",
+ eventAgeString(cn.lastMessageReceived),
+ eventAgeString(cn.completedHandshake),
+ eventAgeString(cn.lastHelpful()),
+ cn.cumInterest(),
+ cn.totalExpectingTime(),
+ )
+ fmt.Fprintf(w,
+ "%s completed, %d pieces touched, good chunks: %v/%v:%v reqq: %d+%v/(%d/%d):%d/%d, flags: %s, dr: %.1f KiB/s\n",
+ cn.completedString(),
+ len(cn.peerTouchedPieces),
+ &cn._stats.ChunksReadUseful,
+ &cn._stats.ChunksRead,
+ &cn._stats.ChunksWritten,
+ cn.requestState.Requests.GetCardinality(),
+ cn.requestState.Cancelled.GetCardinality(),
+ cn.nominalMaxRequests(),
+ cn.PeerMaxRequests,
+ len(cn.peerRequests),
+ localClientReqq,
+ cn.statusFlags(),
+ cn.downloadRate()/(1<<10),
+ )
+ fmt.Fprintf(w, "requested pieces:")
+ cn.iterContiguousPieceRequests(func(piece pieceIndex, count int) {
+ fmt.Fprintf(w, " %v(%v)", piece, count)
+ })
+ fmt.Fprintf(w, "\n")
+}
+
+func (p *Peer) close() {
+ if !p.closed.Set() {
+ return
+ }
+ if p.updateRequestsTimer != nil {
+ p.updateRequestsTimer.Stop()
+ }
+ p.peerImpl.onClose()
+ if p.t != nil {
+ p.t.decPeerPieceAvailability(p)
+ }
+ for _, f := range p.callbacks.PeerClosed {
+ f(p)
+ }
+}
+
+// Peer definitely has a piece, for purposes of requesting. So it's not sufficient that we think
+// they do (known=true).
+func (cn *Peer) peerHasPiece(piece pieceIndex) bool {
+ if all, known := cn.peerHasAllPieces(); all && known {
+ return true
+ }
+ return cn.peerPieces().ContainsInt(piece)
+}
+
+// 64KiB, but temporarily less to work around an issue with WebRTC. TODO: Update when
+// https://github.com/pion/datachannel/issues/59 is fixed.
+const (
+ writeBufferHighWaterLen = 1 << 15
+ writeBufferLowWaterLen = writeBufferHighWaterLen / 2
+)
+
+var (
+ interestedMsgLen = len(pp.Message{Type: pp.Interested}.MustMarshalBinary())
+ requestMsgLen = len(pp.Message{Type: pp.Request}.MustMarshalBinary())
+ // This is the maximum request count that could fit in the write buffer if it's at or below the
+ // low water mark when we run maybeUpdateActualRequestState.
+ maxLocalToRemoteRequests = (writeBufferHighWaterLen - writeBufferLowWaterLen - interestedMsgLen) / requestMsgLen
+)
+
+// The actual value to use as the maximum outbound requests.
+func (cn *Peer) nominalMaxRequests() maxRequests {
+ return maxInt(1, minInt(cn.PeerMaxRequests, cn.peakRequests*2, maxLocalToRemoteRequests))
+}
+
+func (cn *Peer) totalExpectingTime() (ret time.Duration) {
+ ret = cn.cumulativeExpectedToReceiveChunks
+ if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
+ ret += time.Since(cn.lastStartedExpectingToReceiveChunks)
+ }
+ return
+}
+
+func (cn *Peer) setInterested(interested bool) bool {
+ if cn.requestState.Interested == interested {
+ return true
+ }
+ cn.requestState.Interested = interested
+ if interested {
+ cn.lastBecameInterested = time.Now()
+ } else if !cn.lastBecameInterested.IsZero() {
+ cn.priorInterest += time.Since(cn.lastBecameInterested)
+ }
+ cn.updateExpectingChunks()
+ // log.Printf("%p: setting interest: %v", cn, interested)
+ return cn.writeInterested(interested)
+}
+
+// The function takes a message to be sent, and returns true if more messages
+// are okay.
+type messageWriter func(pp.Message) bool
+
+// This function seems to only used by Peer.request. It's all logic checks, so maybe we can no-op it
+// when we want to go fast.
+func (cn *Peer) shouldRequest(r RequestIndex) error {
+ err := cn.t.checkValidReceiveChunk(cn.t.requestIndexToRequest(r))
+ if err != nil {
+ return err
+ }
+ pi := cn.t.pieceIndexOfRequestIndex(r)
+ if cn.requestState.Cancelled.Contains(r) {
+ return errors.New("request is cancelled and waiting acknowledgement")
+ }
+ if !cn.peerHasPiece(pi) {
+ return errors.New("requesting piece peer doesn't have")
+ }
+ if !cn.t.peerIsActive(cn) {
+ panic("requesting but not in active conns")
+ }
+ if cn.closed.IsSet() {
+ panic("requesting when connection is closed")
+ }
+ if cn.t.hashingPiece(pi) {
+ panic("piece is being hashed")
+ }
+ if cn.t.pieceQueuedForHash(pi) {
+ panic("piece is queued for hash")
+ }
+ if cn.peerChoking && !cn.peerAllowedFast.Contains(pi) {
+ // This could occur if we made a request with the fast extension, and then got choked and
+ // haven't had the request rejected yet.
+ if !cn.requestState.Requests.Contains(r) {
+ panic("peer choking and piece not allowed fast")
+ }
+ }
+ return nil
+}
+
+func (cn *Peer) mustRequest(r RequestIndex) bool {
+ more, err := cn.request(r)
+ if err != nil {
+ panic(err)
+ }
+ return more
+}
+
+func (cn *Peer) request(r RequestIndex) (more bool, err error) {
+ if err := cn.shouldRequest(r); err != nil {
+ panic(err)
+ }
+ if cn.requestState.Requests.Contains(r) {
+ return true, nil
+ }
+ if maxRequests(cn.requestState.Requests.GetCardinality()) >= cn.nominalMaxRequests() {
+ return true, errors.New("too many outstanding requests")
+ }
+ cn.requestState.Requests.Add(r)
+ if cn.validReceiveChunks == nil {
+ cn.validReceiveChunks = make(map[RequestIndex]int)
+ }
+ cn.validReceiveChunks[r]++
+ cn.t.requestState[r] = requestState{
+ peer: cn,
+ when: time.Now(),
+ }
+ cn.updateExpectingChunks()
+ ppReq := cn.t.requestIndexToRequest(r)
+ for _, f := range cn.callbacks.SentRequest {
+ f(PeerRequestEvent{cn, ppReq})
+ }
+ return cn.peerImpl._request(ppReq), nil
+}
+
+func (me *Peer) cancel(r RequestIndex) {
+ if !me.deleteRequest(r) {
+ panic("request not existing should have been guarded")
+ }
+ if me._cancel(r) {
+ if !me.requestState.Cancelled.CheckedAdd(r) {
+ panic("request already cancelled")
+ }
+ }
+ me.decPeakRequests()
+ if me.isLowOnRequests() {
+ me.updateRequests("Peer.cancel")
+ }
+}
+
+// Sets a reason to update requests, and if there wasn't already one, handle it.
+func (cn *Peer) updateRequests(reason string) {
+ if cn.needRequestUpdate != "" {
+ return
+ }
+ if reason != peerUpdateRequestsTimerReason && !cn.isLowOnRequests() {
+ return
+ }
+ cn.needRequestUpdate = reason
+ cn.handleUpdateRequests()
+}
+
+// Emits the indices in the Bitmaps bms in order, never repeating any index.
+// skip is mutated during execution, and its initial values will never be
+// emitted.
+func iterBitmapsDistinct(skip *bitmap.Bitmap, bms ...bitmap.Bitmap) iter.Func {
+ return func(cb iter.Callback) {
+ for _, bm := range bms {
+ if !iter.All(
+ func(_i interface{}) bool {
+ i := _i.(int)
+ if skip.Contains(bitmap.BitIndex(i)) {
+ return true
+ }
+ skip.Add(bitmap.BitIndex(i))
+ return cb(i)
+ },
+ bm.Iter,
+ ) {
+ return
+ }
+ }
+ }
+}
+
+func (cn *Peer) peerPiecesChanged() {
+ cn.t.maybeDropMutuallyCompletePeer(cn)
+}
+
+// After handshake, we know what Torrent and Client stats to include for a
+// connection.
+func (cn *Peer) postHandshakeStats(f func(*ConnStats)) {
+ t := cn.t
+ f(&t.stats)
+ f(&t.cl.stats)
+}
+
+// All ConnStats that include this connection. Some objects are not known
+// until the handshake is complete, after which it's expected to reconcile the
+// differences.
+func (cn *Peer) allStats(f func(*ConnStats)) {
+ f(&cn._stats)
+ if cn.reconciledHandshakeStats {
+ cn.postHandshakeStats(f)
+ }
+}
+
+func (cn *Peer) readBytes(n int64) {
+ cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesRead }))
+}
+
+// Returns whether the connection could be useful to us. We're seeding and
+// they want data, we don't have metainfo and they can provide it, etc.
+func (c *Peer) useful() bool {
+ t := c.t
+ if c.closed.IsSet() {
+ return false
+ }
+ if !t.haveInfo() {
+ return c.supportsExtension("ut_metadata")
+ }
+ if t.seeding() && c.peerInterested {
+ return true
+ }
+ if c.peerHasWantedPieces() {
+ return true
+ }
+ return false
+}
+
+func (c *Peer) lastHelpful() (ret time.Time) {
+ ret = c.lastUsefulChunkReceived
+ if c.t.seeding() && c.lastChunkSent.After(ret) {
+ ret = c.lastChunkSent
+ }
+ return
+}
+
+// Returns whether any part of the chunk would lie outside a piece of the given length.
+func chunkOverflowsPiece(cs ChunkSpec, pieceLength pp.Integer) bool {
+ switch {
+ default:
+ return false
+ case cs.Begin+cs.Length > pieceLength:
+ // Check for integer overflow
+ case cs.Begin > pp.IntegerMax-cs.Length:
+ }
+ return true
+}
+
+func runSafeExtraneous(f func()) {
+ if true {
+ go f()
+ } else {
+ f()
+ }
+}
+
+// Returns true if it was valid to reject the request.
+func (c *Peer) remoteRejectedRequest(r RequestIndex) bool {
+ if c.deleteRequest(r) {
+ c.decPeakRequests()
+ } else if !c.requestState.Cancelled.CheckedRemove(r) {
+ return false
+ }
+ if c.isLowOnRequests() {
+ c.updateRequests("Peer.remoteRejectedRequest")
+ }
+ c.decExpectedChunkReceive(r)
+ return true
+}
+
+func (c *Peer) decExpectedChunkReceive(r RequestIndex) {
+ count := c.validReceiveChunks[r]
+ if count == 1 {
+ delete(c.validReceiveChunks, r)
+ } else if count > 1 {
+ c.validReceiveChunks[r] = count - 1
+ } else {
+ panic(r)
+ }
+}
+
+func (c *Peer) doChunkReadStats(size int64) {
+ c.allStats(func(cs *ConnStats) { cs.receivedChunk(size) })
+}
+
+// Handle a received chunk from a peer.
+func (c *Peer) receiveChunk(msg *pp.Message) error {
+ chunksReceived.Add("total", 1)
+
+ ppReq := newRequestFromMessage(msg)
+ t := c.t
+ err := t.checkValidReceiveChunk(ppReq)
+ if err != nil {
+ err = log.WithLevel(log.Warning, err)
+ return err
+ }
+ req := c.t.requestIndexFromRequest(ppReq)
+
+ if c.bannableAddr.Ok {
+ t.smartBanCache.RecordBlock(c.bannableAddr.Value, req, msg.Piece)
+ }
+
+ if c.peerChoking {
+ chunksReceived.Add("while choked", 1)
+ }
+
+ if c.validReceiveChunks[req] <= 0 {
+ chunksReceived.Add("unexpected", 1)
+ return errors.New("received unexpected chunk")
+ }
+ c.decExpectedChunkReceive(req)
+
+ if c.peerChoking && c.peerAllowedFast.Contains(pieceIndex(ppReq.Index)) {
+ chunksReceived.Add("due to allowed fast", 1)
+ }
+
+ // The request needs to be deleted immediately to prevent cancels occurring asynchronously when
+ // have actually already received the piece, while we have the Client unlocked to write the data
+ // out.
+ intended := false
+ {
+ if c.requestState.Requests.Contains(req) {
+ for _, f := range c.callbacks.ReceivedRequested {
+ f(PeerMessageEvent{c, msg})
+ }
+ }
+ // Request has been satisfied.
+ if c.deleteRequest(req) || c.requestState.Cancelled.CheckedRemove(req) {
+ intended = true
+ if !c.peerChoking {
+ c._chunksReceivedWhileExpecting++
+ }
+ if c.isLowOnRequests() {
+ c.updateRequests("Peer.receiveChunk deleted request")
+ }
+ } else {
+ chunksReceived.Add("unintended", 1)
+ }
+ }
+
+ cl := t.cl
+
+ // Do we actually want this chunk?
+ if t.haveChunk(ppReq) {
+ // panic(fmt.Sprintf("%+v", ppReq))
+ chunksReceived.Add("redundant", 1)
+ c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadWasted }))
+ return nil
+ }
+
+ piece := &t.pieces[ppReq.Index]
+
+ c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadUseful }))
+ c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulData }))
+ if intended {
+ c.piecesReceivedSinceLastRequestUpdate++
+ c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulIntendedData }))
+ }
+ for _, f := range c.t.cl.config.Callbacks.ReceivedUsefulData {
+ f(ReceivedUsefulDataEvent{c, msg})
+ }
+ c.lastUsefulChunkReceived = time.Now()
+
+ // Need to record that it hasn't been written yet, before we attempt to do
+ // anything with it.
+ piece.incrementPendingWrites()
+ // Record that we have the chunk, so we aren't trying to download it while
+ // waiting for it to be written to storage.
+ piece.unpendChunkIndex(chunkIndexFromChunkSpec(ppReq.ChunkSpec, t.chunkSize))
+
+ // Cancel pending requests for this chunk from *other* peers.
+ if p := t.requestingPeer(req); p != nil {
+ if p == c {
+ panic("should not be pending request from conn that just received it")
+ }
+ p.cancel(req)
+ }
+
+ err = func() error {
+ cl.unlock()
+ defer cl.lock()
+ concurrentChunkWrites.Add(1)
+ defer concurrentChunkWrites.Add(-1)
+ // Write the chunk out. Note that the upper bound on chunk writing concurrency will be the
+ // number of connections. We write inline with receiving the chunk (with this lock dance),
+ // because we want to handle errors synchronously and I haven't thought of a nice way to
+ // defer any concurrency to the storage and have that notify the client of errors. TODO: Do
+ // that instead.
+ return t.writeChunk(int(msg.Index), int64(msg.Begin), msg.Piece)
+ }()
+
+ piece.decrementPendingWrites()
+
+ if err != nil {
+ c.logger.WithDefaultLevel(log.Error).Printf("writing received chunk %v: %v", req, err)
+ t.pendRequest(req)
+ // Necessary to pass TestReceiveChunkStorageFailureSeederFastExtensionDisabled. I think a
+ // request update runs while we're writing the chunk that just failed. Then we never do a
+ // fresh update after pending the failed request.
+ c.updateRequests("Peer.receiveChunk error writing chunk")
+ t.onWriteChunkErr(err)
+ return nil
+ }
+
+ c.onDirtiedPiece(pieceIndex(ppReq.Index))
+
+ // We need to ensure the piece is only queued once, so only the last chunk writer gets this job.
+ if t.pieceAllDirty(pieceIndex(ppReq.Index)) && piece.pendingWrites == 0 {
+ t.queuePieceCheck(pieceIndex(ppReq.Index))
+ // We don't pend all chunks here anymore because we don't want code dependent on the dirty
+ // chunk status (such as the haveChunk call above) to have to check all the various other
+ // piece states like queued for hash, hashing etc. This does mean that we need to be sure
+ // that chunk pieces are pended at an appropriate time later however.
+ }
+
+ cl.event.Broadcast()
+ // We do this because we've written a chunk, and may change PieceState.Partial.
+ t.publishPieceChange(pieceIndex(ppReq.Index))
+
+ return nil
+}
+
+func (c *Peer) onDirtiedPiece(piece pieceIndex) {
+ if c.peerTouchedPieces == nil {
+ c.peerTouchedPieces = make(map[pieceIndex]struct{})
+ }
+ c.peerTouchedPieces[piece] = struct{}{}
+ ds := &c.t.pieces[piece].dirtiers
+ if *ds == nil {
+ *ds = make(map[*Peer]struct{})
+ }
+ (*ds)[c] = struct{}{}
+}
+
+func (cn *Peer) netGoodPiecesDirtied() int64 {
+ return cn._stats.PiecesDirtiedGood.Int64() - cn._stats.PiecesDirtiedBad.Int64()
+}
+
+func (c *Peer) peerHasWantedPieces() bool {
+ if all, _ := c.peerHasAllPieces(); all {
+ return !c.t.haveAllPieces() && !c.t._pendingPieces.IsEmpty()
+ }
+ if !c.t.haveInfo() {
+ return !c.peerPieces().IsEmpty()
+ }
+ return c.peerPieces().Intersects(&c.t._pendingPieces)
+}
+
+// Returns true if an outstanding request is removed. Cancelled requests should be handled
+// separately.
+func (c *Peer) deleteRequest(r RequestIndex) bool {
+ if !c.requestState.Requests.CheckedRemove(r) {
+ return false
+ }
+ for _, f := range c.callbacks.DeletedRequest {
+ f(PeerRequestEvent{c, c.t.requestIndexToRequest(r)})
+ }
+ c.updateExpectingChunks()
+ if c.t.requestingPeer(r) != c {
+ panic("only one peer should have a given request at a time")
+ }
+ delete(c.t.requestState, r)
+ // c.t.iterPeers(func(p *Peer) {
+ // if p.isLowOnRequests() {
+ // p.updateRequests("Peer.deleteRequest")
+ // }
+ // })
+ return true
+}
+
+func (c *Peer) deleteAllRequests(reason string) {
+ if c.requestState.Requests.IsEmpty() {
+ return
+ }
+ c.requestState.Requests.IterateSnapshot(func(x RequestIndex) bool {
+ if !c.deleteRequest(x) {
+ panic("request should exist")
+ }
+ return true
+ })
+ c.assertNoRequests()
+ c.t.iterPeers(func(p *Peer) {
+ if p.isLowOnRequests() {
+ p.updateRequests(reason)
+ }
+ })
+ return
+}
+
+func (c *Peer) assertNoRequests() {
+ if !c.requestState.Requests.IsEmpty() {
+ panic(c.requestState.Requests.GetCardinality())
+ }
+}
+
+func (c *Peer) cancelAllRequests() {
+ c.requestState.Requests.IterateSnapshot(func(x RequestIndex) bool {
+ c.cancel(x)
+ return true
+ })
+ c.assertNoRequests()
+ return
+}
+
+func (c *Peer) peerPriority() (peerPriority, error) {
+ return bep40Priority(c.remoteIpPort(), c.localPublicAddr)
+}
+
+func (c *Peer) remoteIp() net.IP {
+ host, _, _ := net.SplitHostPort(c.RemoteAddr.String())
+ return net.ParseIP(host)
+}
+
+func (c *Peer) remoteIpPort() IpPort {
+ ipa, _ := tryIpPortFromNetAddr(c.RemoteAddr)
+ return IpPort{ipa.IP, uint16(ipa.Port)}
+}
+
+func (c *Peer) trust() connectionTrust {
+ return connectionTrust{c.trusted, c.netGoodPiecesDirtied()}
+}
+
+type connectionTrust struct {
+ Implicit bool
+ NetGoodPiecesDirted int64
+}
+
+func (l connectionTrust) Less(r connectionTrust) bool {
+ return multiless.New().Bool(l.Implicit, r.Implicit).Int64(l.NetGoodPiecesDirted, r.NetGoodPiecesDirted).Less()
+}
+
+// Returns a new Bitmap that includes bits for all pieces the peer could have based on their claims.
+func (cn *Peer) newPeerPieces() *roaring.Bitmap {
+ // TODO: Can we use copy on write?
+ ret := cn.peerPieces().Clone()
+ if all, _ := cn.peerHasAllPieces(); all {
+ if cn.t.haveInfo() {
+ ret.AddRange(0, bitmap.BitRange(cn.t.numPieces()))
+ } else {
+ ret.AddRange(0, bitmap.ToEnd)
+ }
+ }
+ return ret
+}
+
+func (cn *Peer) stats() *ConnStats {
+ return &cn._stats
+}
+
+func (p *Peer) TryAsPeerConn() (*PeerConn, bool) {
+ pc, ok := p.peerImpl.(*PeerConn)
+ return pc, ok
+}
+
+func (p *Peer) uncancelledRequests() uint64 {
+ return p.requestState.Requests.GetCardinality()
+}
+
type peerLocalPublicAddr = IpPort
func (p *Peer) isLowOnRequests() bool {
"net"
"strconv"
"strings"
- "sync/atomic"
"time"
"github.com/RoaringBitmap/roaring"
- "github.com/anacrolix/chansync"
. "github.com/anacrolix/generics"
"github.com/anacrolix/log"
- "github.com/anacrolix/missinggo/iter"
"github.com/anacrolix/missinggo/v2/bitmap"
"github.com/anacrolix/multiless"
- "github.com/anacrolix/torrent/internal/alloclim"
"golang.org/x/time/rate"
"github.com/anacrolix/torrent/bencode"
+ "github.com/anacrolix/torrent/internal/alloclim"
"github.com/anacrolix/torrent/metainfo"
"github.com/anacrolix/torrent/mse"
pp "github.com/anacrolix/torrent/peer_protocol"
- request_strategy "github.com/anacrolix/torrent/request-strategy"
- "github.com/anacrolix/torrent/typed-roaring"
-)
-
-type PeerSource string
-
-const (
- PeerSourceTracker = "Tr"
- PeerSourceIncoming = "I"
- PeerSourceDhtGetPeers = "Hg" // Peers we found by searching a DHT.
- PeerSourceDhtAnnouncePeer = "Ha" // Peers that were announced to us by a DHT.
- PeerSourcePex = "X"
- // The peer was given directly, such as through a magnet link.
- PeerSourceDirect = "M"
)
-type peerRequestState struct {
- data []byte
- allocReservation *alloclim.Reservation
-}
-
-type PeerRemoteAddr interface {
- String() string
-}
-
-type (
- // Since we have to store all the requests in memory, we can't reasonably exceed what could be
- // indexed with the memory space available.
- maxRequests = int
-)
-
-type Peer struct {
- // First to ensure 64-bit alignment for atomics. See #262.
- _stats ConnStats
-
- t *Torrent
-
- peerImpl
- callbacks *Callbacks
-
- outgoing bool
- Network string
- RemoteAddr PeerRemoteAddr
- // The local address as observed by the remote peer. WebRTC seems to get this right without needing hints from the
- // config.
- localPublicAddr peerLocalPublicAddr
- bannableAddr Option[bannableAddr]
- // True if the connection is operating over MSE obfuscation.
- headerEncrypted bool
- cryptoMethod mse.CryptoMethod
- Discovery PeerSource
- trusted bool
- closed chansync.SetOnce
- // Set true after we've added our ConnStats generated during handshake to
- // other ConnStat instances as determined when the *Torrent became known.
- reconciledHandshakeStats bool
-
- lastMessageReceived time.Time
- completedHandshake time.Time
- lastUsefulChunkReceived time.Time
- lastChunkSent time.Time
-
- // Stuff controlled by the local peer.
- needRequestUpdate string
- requestState request_strategy.PeerRequestState
- updateRequestsTimer *time.Timer
- lastRequestUpdate time.Time
- peakRequests maxRequests
- lastBecameInterested time.Time
- priorInterest time.Duration
-
- lastStartedExpectingToReceiveChunks time.Time
- cumulativeExpectedToReceiveChunks time.Duration
- _chunksReceivedWhileExpecting int64
-
- choking bool
- piecesReceivedSinceLastRequestUpdate maxRequests
- maxPiecesReceivedBetweenRequestUpdates maxRequests
- // Chunks that we might reasonably expect to receive from the peer. Due to latency, buffering,
- // and implementation differences, we may receive chunks that are no longer in the set of
- // requests actually want. This could use a roaring.BSI if the memory use becomes noticeable.
- validReceiveChunks map[RequestIndex]int
- // Indexed by metadata piece, set to true if posted and pending a
- // response.
- metadataRequests []bool
- sentHaves bitmap.Bitmap
-
- // Stuff controlled by the remote peer.
- peerInterested bool
- peerChoking bool
- peerRequests map[Request]*peerRequestState
- PeerPrefersEncryption bool // as indicated by 'e' field in extension handshake
- PeerListenPort int
- // The highest possible number of pieces the torrent could have based on
- // communication with the peer. Generally only useful until we have the
- // torrent info.
- peerMinPieces pieceIndex
- // Pieces we've accepted chunks for from the peer.
- peerTouchedPieces map[pieceIndex]struct{}
- peerAllowedFast typedRoaring.Bitmap[pieceIndex]
-
- PeerMaxRequests maxRequests // Maximum pending requests the peer allows.
- PeerExtensionIDs map[pp.ExtensionName]pp.ExtensionNumber
- PeerClientName atomic.Value
-
- logger log.Logger
-}
-
-type peerRequests = orderedBitmap[RequestIndex]
-
-func (p *Peer) initRequestState() {
- p.requestState.Requests = &peerRequests{}
-}
-
// Maintains the state of a BitTorrent-protocol based connection with a peer.
type PeerConn struct {
Peer
return []string{fmt.Sprintf("%+-55q %s %s", cn.PeerID, cn.PeerExtensionBytes, cn.connString)}
}
-func (cn *Peer) updateExpectingChunks() {
- if cn.expectingChunks() {
- if cn.lastStartedExpectingToReceiveChunks.IsZero() {
- cn.lastStartedExpectingToReceiveChunks = time.Now()
- }
- } else {
- if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
- cn.cumulativeExpectedToReceiveChunks += time.Since(cn.lastStartedExpectingToReceiveChunks)
- cn.lastStartedExpectingToReceiveChunks = time.Time{}
- }
- }
-}
-
-func (cn *Peer) expectingChunks() bool {
- if cn.requestState.Requests.IsEmpty() {
- return false
- }
- if !cn.requestState.Interested {
- return false
- }
- if !cn.peerChoking {
- return true
- }
- haveAllowedFastRequests := false
- cn.peerAllowedFast.Iterate(func(i pieceIndex) bool {
- haveAllowedFastRequests = roaringBitmapRangeCardinality[RequestIndex](
- cn.requestState.Requests,
- cn.t.pieceRequestIndexOffset(i),
- cn.t.pieceRequestIndexOffset(i+1),
- ) == 0
- return !haveAllowedFastRequests
- })
- return haveAllowedFastRequests
-}
-
-func (cn *Peer) remoteChokingPiece(piece pieceIndex) bool {
- return cn.peerChoking && !cn.peerAllowedFast.Contains(piece)
-}
-
// Returns true if the connection is over IPv6.
func (cn *PeerConn) ipv6() bool {
ip := cn.remoteIp()
return ml.Less()
}
-func (cn *Peer) cumInterest() time.Duration {
- ret := cn.priorInterest
- if cn.requestState.Interested {
- ret += time.Since(cn.lastBecameInterested)
- }
- return ret
-}
-
func (cn *PeerConn) peerHasAllPieces() (all, known bool) {
if cn.peerSentHaveAll {
return true, true
return cn._peerPieces.GetCardinality() == uint64(cn.t.numPieces()), true
}
-func (cn *Peer) locker() *lockWithDeferreds {
- return cn.t.cl.locker()
-}
-
-func (cn *Peer) supportsExtension(ext pp.ExtensionName) bool {
- _, ok := cn.PeerExtensionIDs[ext]
- return ok
-}
-
-// The best guess at number of pieces in the torrent for this peer.
-func (cn *Peer) bestPeerNumPieces() pieceIndex {
- if cn.t.haveInfo() {
- return cn.t.numPieces()
- }
- return cn.peerMinPieces
-}
-
-func (cn *Peer) completedString() string {
- have := pieceIndex(cn.peerPieces().GetCardinality())
- if all, _ := cn.peerHasAllPieces(); all {
- have = cn.bestPeerNumPieces()
- }
- return fmt.Sprintf("%d/%d", have, cn.bestPeerNumPieces())
-}
-
func (cn *PeerConn) onGotInfo(info *metainfo.Info) {
cn.setNumPieces(info.NumPieces())
}
return &cn._peerPieces
}
-func eventAgeString(t time.Time) string {
- if t.IsZero() {
- return "never"
- }
- return fmt.Sprintf("%.2fs ago", time.Since(t).Seconds())
-}
-
func (cn *PeerConn) connectionFlags() (ret string) {
c := func(b byte) {
ret += string([]byte{b})
return parseNetworkString(cn.Network).Udp
}
-// Inspired by https://github.com/transmission/transmission/wiki/Peer-Status-Text.
-func (cn *Peer) statusFlags() (ret string) {
- c := func(b byte) {
- ret += string([]byte{b})
- }
- if cn.requestState.Interested {
- c('i')
- }
- if cn.choking {
- c('c')
- }
- c('-')
- ret += cn.connectionFlags()
- c('-')
- if cn.peerInterested {
- c('i')
- }
- if cn.peerChoking {
- c('c')
- }
- return
-}
-
-func (cn *Peer) downloadRate() float64 {
- num := cn._stats.BytesReadUsefulData.Int64()
- if num == 0 {
- return 0
- }
- return float64(num) / cn.totalExpectingTime().Seconds()
-}
-
-func (cn *Peer) DownloadRate() float64 {
- cn.locker().RLock()
- defer cn.locker().RUnlock()
-
- return cn.downloadRate()
-}
-
-func (cn *Peer) iterContiguousPieceRequests(f func(piece pieceIndex, count int)) {
- var last Option[pieceIndex]
- var count int
- next := func(item Option[pieceIndex]) {
- if item == last {
- count++
- } else {
- if count != 0 {
- f(last.Value, count)
- }
- last = item
- count = 1
- }
- }
- cn.requestState.Requests.Iterate(func(requestIndex request_strategy.RequestIndex) bool {
- next(Some(cn.t.pieceIndexOfRequestIndex(requestIndex)))
- return true
- })
- next(None[pieceIndex]())
-}
-
-func (cn *Peer) writeStatus(w io.Writer, t *Torrent) {
- // \t isn't preserved in <pre> blocks?
- if cn.closed.IsSet() {
- fmt.Fprint(w, "CLOSED: ")
- }
- fmt.Fprintln(w, strings.Join(cn.peerImplStatusLines(), "\n"))
- prio, err := cn.peerPriority()
- prioStr := fmt.Sprintf("%08x", prio)
- if err != nil {
- prioStr += ": " + err.Error()
- }
- fmt.Fprintf(w, "bep40-prio: %v\n", prioStr)
- fmt.Fprintf(w, "last msg: %s, connected: %s, last helpful: %s, itime: %s, etime: %s\n",
- eventAgeString(cn.lastMessageReceived),
- eventAgeString(cn.completedHandshake),
- eventAgeString(cn.lastHelpful()),
- cn.cumInterest(),
- cn.totalExpectingTime(),
- )
- fmt.Fprintf(w,
- "%s completed, %d pieces touched, good chunks: %v/%v:%v reqq: %d+%v/(%d/%d):%d/%d, flags: %s, dr: %.1f KiB/s\n",
- cn.completedString(),
- len(cn.peerTouchedPieces),
- &cn._stats.ChunksReadUseful,
- &cn._stats.ChunksRead,
- &cn._stats.ChunksWritten,
- cn.requestState.Requests.GetCardinality(),
- cn.requestState.Cancelled.GetCardinality(),
- cn.nominalMaxRequests(),
- cn.PeerMaxRequests,
- len(cn.peerRequests),
- localClientReqq,
- cn.statusFlags(),
- cn.downloadRate()/(1<<10),
- )
- fmt.Fprintf(w, "requested pieces:")
- cn.iterContiguousPieceRequests(func(piece pieceIndex, count int) {
- fmt.Fprintf(w, " %v(%v)", piece, count)
- })
- fmt.Fprintf(w, "\n")
-}
-
-func (p *Peer) close() {
- if !p.closed.Set() {
- return
- }
- if p.updateRequestsTimer != nil {
- p.updateRequestsTimer.Stop()
- }
- p.peerImpl.onClose()
- if p.t != nil {
- p.t.decPeerPieceAvailability(p)
- }
- for _, f := range p.callbacks.PeerClosed {
- f(p)
- }
-}
-
func (cn *PeerConn) onClose() {
if cn.pex.IsEnabled() {
cn.pex.Close()
}
}
-// Peer definitely has a piece, for purposes of requesting. So it's not sufficient that we think
-// they do (known=true).
-func (cn *Peer) peerHasPiece(piece pieceIndex) bool {
- if all, known := cn.peerHasAllPieces(); all && known {
- return true
- }
- return cn.peerPieces().ContainsInt(piece)
-}
-
-// 64KiB, but temporarily less to work around an issue with WebRTC. TODO: Update when
-// https://github.com/pion/datachannel/issues/59 is fixed.
-const (
- writeBufferHighWaterLen = 1 << 15
- writeBufferLowWaterLen = writeBufferHighWaterLen / 2
-)
-
// Writes a message into the write buffer. Returns whether it's okay to keep writing. Writing is
// done asynchronously, so it may be that we're not able to honour backpressure from this method.
func (cn *PeerConn) write(msg pp.Message) bool {
return index < len(cn.metadataRequests) && cn.metadataRequests[index]
}
-var (
- interestedMsgLen = len(pp.Message{Type: pp.Interested}.MustMarshalBinary())
- requestMsgLen = len(pp.Message{Type: pp.Request}.MustMarshalBinary())
- // This is the maximum request count that could fit in the write buffer if it's at or below the
- // low water mark when we run maybeUpdateActualRequestState.
- maxLocalToRemoteRequests = (writeBufferHighWaterLen - writeBufferLowWaterLen - interestedMsgLen) / requestMsgLen
-)
-
-// The actual value to use as the maximum outbound requests.
-func (cn *Peer) nominalMaxRequests() maxRequests {
- return maxInt(1, minInt(cn.PeerMaxRequests, cn.peakRequests*2, maxLocalToRemoteRequests))
-}
-
-func (cn *Peer) totalExpectingTime() (ret time.Duration) {
- ret = cn.cumulativeExpectedToReceiveChunks
- if !cn.lastStartedExpectingToReceiveChunks.IsZero() {
- ret += time.Since(cn.lastStartedExpectingToReceiveChunks)
- }
- return
-}
-
func (cn *PeerConn) onPeerSentCancel(r Request) {
if _, ok := cn.peerRequests[r]; !ok {
torrent.Add("unexpected cancels received", 1)
})
}
-func (cn *Peer) setInterested(interested bool) bool {
- if cn.requestState.Interested == interested {
- return true
- }
- cn.requestState.Interested = interested
- if interested {
- cn.lastBecameInterested = time.Now()
- } else if !cn.lastBecameInterested.IsZero() {
- cn.priorInterest += time.Since(cn.lastBecameInterested)
- }
- cn.updateExpectingChunks()
- // log.Printf("%p: setting interest: %v", cn, interested)
- return cn.writeInterested(interested)
-}
-
func (pc *PeerConn) writeInterested(interested bool) bool {
return pc.write(pp.Message{
Type: func() pp.MessageType {
})
}
-// The function takes a message to be sent, and returns true if more messages
-// are okay.
-type messageWriter func(pp.Message) bool
-
-// This function seems to only used by Peer.request. It's all logic checks, so maybe we can no-op it
-// when we want to go fast.
-func (cn *Peer) shouldRequest(r RequestIndex) error {
- err := cn.t.checkValidReceiveChunk(cn.t.requestIndexToRequest(r))
- if err != nil {
- return err
- }
- pi := cn.t.pieceIndexOfRequestIndex(r)
- if cn.requestState.Cancelled.Contains(r) {
- return errors.New("request is cancelled and waiting acknowledgement")
- }
- if !cn.peerHasPiece(pi) {
- return errors.New("requesting piece peer doesn't have")
- }
- if !cn.t.peerIsActive(cn) {
- panic("requesting but not in active conns")
- }
- if cn.closed.IsSet() {
- panic("requesting when connection is closed")
- }
- if cn.t.hashingPiece(pi) {
- panic("piece is being hashed")
- }
- if cn.t.pieceQueuedForHash(pi) {
- panic("piece is queued for hash")
- }
- if cn.peerChoking && !cn.peerAllowedFast.Contains(pi) {
- // This could occur if we made a request with the fast extension, and then got choked and
- // haven't had the request rejected yet.
- if !cn.requestState.Requests.Contains(r) {
- panic("peer choking and piece not allowed fast")
- }
- }
- return nil
-}
-
-func (cn *Peer) mustRequest(r RequestIndex) bool {
- more, err := cn.request(r)
- if err != nil {
- panic(err)
- }
- return more
-}
-
-func (cn *Peer) request(r RequestIndex) (more bool, err error) {
- if err := cn.shouldRequest(r); err != nil {
- panic(err)
- }
- if cn.requestState.Requests.Contains(r) {
- return true, nil
- }
- if maxRequests(cn.requestState.Requests.GetCardinality()) >= cn.nominalMaxRequests() {
- return true, errors.New("too many outstanding requests")
- }
- cn.requestState.Requests.Add(r)
- if cn.validReceiveChunks == nil {
- cn.validReceiveChunks = make(map[RequestIndex]int)
- }
- cn.validReceiveChunks[r]++
- cn.t.requestState[r] = requestState{
- peer: cn,
- when: time.Now(),
- }
- cn.updateExpectingChunks()
- ppReq := cn.t.requestIndexToRequest(r)
- for _, f := range cn.callbacks.SentRequest {
- f(PeerRequestEvent{cn, ppReq})
- }
- return cn.peerImpl._request(ppReq), nil
-}
-
func (me *PeerConn) _request(r Request) bool {
return me.write(pp.Message{
Type: pp.Request,
})
}
-func (me *Peer) cancel(r RequestIndex) {
- if !me.deleteRequest(r) {
- panic("request not existing should have been guarded")
- }
- if me._cancel(r) {
- if !me.requestState.Cancelled.CheckedAdd(r) {
- panic("request already cancelled")
- }
- }
- me.decPeakRequests()
- if me.isLowOnRequests() {
- me.updateRequests("Peer.cancel")
- }
-}
-
func (me *PeerConn) _cancel(r RequestIndex) bool {
me.write(makeCancelMessage(me.t.requestIndexToRequest(r)))
// Transmission does not send rejects for received cancels. See
cn.sentHaves = bitmap.Bitmap{cn.t._completedPieces.Clone()}
}
-// Sets a reason to update requests, and if there wasn't already one, handle it.
-func (cn *Peer) updateRequests(reason string) {
- if cn.needRequestUpdate != "" {
- return
- }
- if reason != peerUpdateRequestsTimerReason && !cn.isLowOnRequests() {
- return
- }
- cn.needRequestUpdate = reason
- cn.handleUpdateRequests()
-}
-
func (cn *PeerConn) handleUpdateRequests() {
// The writer determines the request state as needed when it can write.
cn.tickleWriter()
}
-// Emits the indices in the Bitmaps bms in order, never repeating any index.
-// skip is mutated during execution, and its initial values will never be
-// emitted.
-func iterBitmapsDistinct(skip *bitmap.Bitmap, bms ...bitmap.Bitmap) iter.Func {
- return func(cb iter.Callback) {
- for _, bm := range bms {
- if !iter.All(
- func(_i interface{}) bool {
- i := _i.(int)
- if skip.Contains(bitmap.BitIndex(i)) {
- return true
- }
- skip.Add(bitmap.BitIndex(i))
- return cb(i)
- },
- bm.Iter,
- ) {
- return
- }
- }
- }
-}
-
-func (cn *Peer) peerPiecesChanged() {
- cn.t.maybeDropMutuallyCompletePeer(cn)
-}
-
func (cn *PeerConn) raisePeerMinPieces(newMin pieceIndex) {
if newMin > cn.peerMinPieces {
cn.peerMinPieces = newMin
cn.allStats(func(cs *ConnStats) { cs.wroteMsg(msg) })
}
-// After handshake, we know what Torrent and Client stats to include for a
-// connection.
-func (cn *Peer) postHandshakeStats(f func(*ConnStats)) {
- t := cn.t
- f(&t.stats)
- f(&t.cl.stats)
-}
-
-// All ConnStats that include this connection. Some objects are not known
-// until the handshake is complete, after which it's expected to reconcile the
-// differences.
-func (cn *Peer) allStats(f func(*ConnStats)) {
- f(&cn._stats)
- if cn.reconciledHandshakeStats {
- cn.postHandshakeStats(f)
- }
-}
-
func (cn *PeerConn) wroteBytes(n int64) {
cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesWritten }))
}
-func (cn *Peer) readBytes(n int64) {
- cn.allStats(add(n, func(cs *ConnStats) *Count { return &cs.BytesRead }))
-}
-
-// Returns whether the connection could be useful to us. We're seeding and
-// they want data, we don't have metainfo and they can provide it, etc.
-func (c *Peer) useful() bool {
- t := c.t
- if c.closed.IsSet() {
- return false
- }
- if !t.haveInfo() {
- return c.supportsExtension("ut_metadata")
- }
- if t.seeding() && c.peerInterested {
- return true
- }
- if c.peerHasWantedPieces() {
- return true
- }
- return false
-}
-
-func (c *Peer) lastHelpful() (ret time.Time) {
- ret = c.lastUsefulChunkReceived
- if c.t.seeding() && c.lastChunkSent.After(ret) {
- ret = c.lastChunkSent
- }
- return
-}
-
func (c *PeerConn) fastEnabled() bool {
return c.PeerExtensionBytes.SupportsFast() && c.t.cl.config.Extensions.SupportsFast()
}
return Some(uploadRateLimiter.Burst())
}
-// Returns whether any part of the chunk would lie outside a piece of the given length.
-func chunkOverflowsPiece(cs ChunkSpec, pieceLength pp.Integer) bool {
- switch {
- default:
- return false
- case cs.Begin+cs.Length > pieceLength:
- // Check for integer overflow
- case cs.Begin > pp.IntegerMax-cs.Length:
- }
- return true
-}
-
// startFetch is for testing purposes currently.
func (c *PeerConn) onReadRequest(r Request, startFetch bool) error {
requestedChunkLengths.Add(strconv.FormatUint(r.Length.Uint64(), 10), 1)
return b, err
}
-func runSafeExtraneous(f func()) {
- if true {
- go f()
- } else {
- f()
- }
-}
-
func (c *PeerConn) logProtocolBehaviour(level log.Level, format string, arg ...interface{}) {
c.logger.WithContextText(fmt.Sprintf(
"peer id %q, ext v %q", c.PeerID, c.PeerClientName.Load(),
}
}
-// Returns true if it was valid to reject the request.
-func (c *Peer) remoteRejectedRequest(r RequestIndex) bool {
- if c.deleteRequest(r) {
- c.decPeakRequests()
- } else if !c.requestState.Cancelled.CheckedRemove(r) {
- return false
- }
- if c.isLowOnRequests() {
- c.updateRequests("Peer.remoteRejectedRequest")
- }
- c.decExpectedChunkReceive(r)
- return true
-}
-
-func (c *Peer) decExpectedChunkReceive(r RequestIndex) {
- count := c.validReceiveChunks[r]
- if count == 1 {
- delete(c.validReceiveChunks, r)
- } else if count > 1 {
- c.validReceiveChunks[r] = count - 1
- } else {
- panic(r)
- }
-}
-
func (c *PeerConn) onReadExtendedMsg(id pp.ExtensionNumber, payload []byte) (err error) {
defer func() {
// TODO: Should we still do this?
}{cn.r, cn.w}
}
-func (c *Peer) doChunkReadStats(size int64) {
- c.allStats(func(cs *ConnStats) { cs.receivedChunk(size) })
-}
-
-// Handle a received chunk from a peer.
-func (c *Peer) receiveChunk(msg *pp.Message) error {
- chunksReceived.Add("total", 1)
-
- ppReq := newRequestFromMessage(msg)
- t := c.t
- err := t.checkValidReceiveChunk(ppReq)
- if err != nil {
- err = log.WithLevel(log.Warning, err)
- return err
- }
- req := c.t.requestIndexFromRequest(ppReq)
-
- if c.bannableAddr.Ok {
- t.smartBanCache.RecordBlock(c.bannableAddr.Value, req, msg.Piece)
- }
-
- if c.peerChoking {
- chunksReceived.Add("while choked", 1)
- }
-
- if c.validReceiveChunks[req] <= 0 {
- chunksReceived.Add("unexpected", 1)
- return errors.New("received unexpected chunk")
- }
- c.decExpectedChunkReceive(req)
-
- if c.peerChoking && c.peerAllowedFast.Contains(pieceIndex(ppReq.Index)) {
- chunksReceived.Add("due to allowed fast", 1)
- }
-
- // The request needs to be deleted immediately to prevent cancels occurring asynchronously when
- // have actually already received the piece, while we have the Client unlocked to write the data
- // out.
- intended := false
- {
- if c.requestState.Requests.Contains(req) {
- for _, f := range c.callbacks.ReceivedRequested {
- f(PeerMessageEvent{c, msg})
- }
- }
- // Request has been satisfied.
- if c.deleteRequest(req) || c.requestState.Cancelled.CheckedRemove(req) {
- intended = true
- if !c.peerChoking {
- c._chunksReceivedWhileExpecting++
- }
- if c.isLowOnRequests() {
- c.updateRequests("Peer.receiveChunk deleted request")
- }
- } else {
- chunksReceived.Add("unintended", 1)
- }
- }
-
- cl := t.cl
-
- // Do we actually want this chunk?
- if t.haveChunk(ppReq) {
- // panic(fmt.Sprintf("%+v", ppReq))
- chunksReceived.Add("redundant", 1)
- c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadWasted }))
- return nil
- }
-
- piece := &t.pieces[ppReq.Index]
-
- c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.ChunksReadUseful }))
- c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulData }))
- if intended {
- c.piecesReceivedSinceLastRequestUpdate++
- c.allStats(add(int64(len(msg.Piece)), func(cs *ConnStats) *Count { return &cs.BytesReadUsefulIntendedData }))
- }
- for _, f := range c.t.cl.config.Callbacks.ReceivedUsefulData {
- f(ReceivedUsefulDataEvent{c, msg})
- }
- c.lastUsefulChunkReceived = time.Now()
-
- // Need to record that it hasn't been written yet, before we attempt to do
- // anything with it.
- piece.incrementPendingWrites()
- // Record that we have the chunk, so we aren't trying to download it while
- // waiting for it to be written to storage.
- piece.unpendChunkIndex(chunkIndexFromChunkSpec(ppReq.ChunkSpec, t.chunkSize))
-
- // Cancel pending requests for this chunk from *other* peers.
- if p := t.requestingPeer(req); p != nil {
- if p == c {
- panic("should not be pending request from conn that just received it")
- }
- p.cancel(req)
- }
-
- err = func() error {
- cl.unlock()
- defer cl.lock()
- concurrentChunkWrites.Add(1)
- defer concurrentChunkWrites.Add(-1)
- // Write the chunk out. Note that the upper bound on chunk writing concurrency will be the
- // number of connections. We write inline with receiving the chunk (with this lock dance),
- // because we want to handle errors synchronously and I haven't thought of a nice way to
- // defer any concurrency to the storage and have that notify the client of errors. TODO: Do
- // that instead.
- return t.writeChunk(int(msg.Index), int64(msg.Begin), msg.Piece)
- }()
-
- piece.decrementPendingWrites()
-
- if err != nil {
- c.logger.WithDefaultLevel(log.Error).Printf("writing received chunk %v: %v", req, err)
- t.pendRequest(req)
- // Necessary to pass TestReceiveChunkStorageFailureSeederFastExtensionDisabled. I think a
- // request update runs while we're writing the chunk that just failed. Then we never do a
- // fresh update after pending the failed request.
- c.updateRequests("Peer.receiveChunk error writing chunk")
- t.onWriteChunkErr(err)
- return nil
- }
-
- c.onDirtiedPiece(pieceIndex(ppReq.Index))
-
- // We need to ensure the piece is only queued once, so only the last chunk writer gets this job.
- if t.pieceAllDirty(pieceIndex(ppReq.Index)) && piece.pendingWrites == 0 {
- t.queuePieceCheck(pieceIndex(ppReq.Index))
- // We don't pend all chunks here anymore because we don't want code dependent on the dirty
- // chunk status (such as the haveChunk call above) to have to check all the various other
- // piece states like queued for hash, hashing etc. This does mean that we need to be sure
- // that chunk pieces are pended at an appropriate time later however.
- }
-
- cl.event.Broadcast()
- // We do this because we've written a chunk, and may change PieceState.Partial.
- t.publishPieceChange(pieceIndex(ppReq.Index))
-
- return nil
-}
-
-func (c *Peer) onDirtiedPiece(piece pieceIndex) {
- if c.peerTouchedPieces == nil {
- c.peerTouchedPieces = make(map[pieceIndex]struct{})
- }
- c.peerTouchedPieces[piece] = struct{}{}
- ds := &c.t.pieces[piece].dirtiers
- if *ds == nil {
- *ds = make(map[*Peer]struct{})
- }
- (*ds)[c] = struct{}{}
-}
-
func (c *PeerConn) uploadAllowed() bool {
if c.t.cl.config.NoUpload {
return false
cn.t.cl.banPeerIP(cn.remoteIp())
}
-func (cn *Peer) netGoodPiecesDirtied() int64 {
- return cn._stats.PiecesDirtiedGood.Int64() - cn._stats.PiecesDirtiedBad.Int64()
-}
-
-func (c *Peer) peerHasWantedPieces() bool {
- if all, _ := c.peerHasAllPieces(); all {
- return !c.t.haveAllPieces() && !c.t._pendingPieces.IsEmpty()
- }
- if !c.t.haveInfo() {
- return !c.peerPieces().IsEmpty()
- }
- return c.peerPieces().Intersects(&c.t._pendingPieces)
-}
-
-// Returns true if an outstanding request is removed. Cancelled requests should be handled
-// separately.
-func (c *Peer) deleteRequest(r RequestIndex) bool {
- if !c.requestState.Requests.CheckedRemove(r) {
- return false
- }
- for _, f := range c.callbacks.DeletedRequest {
- f(PeerRequestEvent{c, c.t.requestIndexToRequest(r)})
- }
- c.updateExpectingChunks()
- if c.t.requestingPeer(r) != c {
- panic("only one peer should have a given request at a time")
- }
- delete(c.t.requestState, r)
- // c.t.iterPeers(func(p *Peer) {
- // if p.isLowOnRequests() {
- // p.updateRequests("Peer.deleteRequest")
- // }
- // })
- return true
-}
-
-func (c *Peer) deleteAllRequests(reason string) {
- if c.requestState.Requests.IsEmpty() {
- return
- }
- c.requestState.Requests.IterateSnapshot(func(x RequestIndex) bool {
- if !c.deleteRequest(x) {
- panic("request should exist")
- }
- return true
- })
- c.assertNoRequests()
- c.t.iterPeers(func(p *Peer) {
- if p.isLowOnRequests() {
- p.updateRequests(reason)
- }
- })
- return
-}
-
-func (c *Peer) assertNoRequests() {
- if !c.requestState.Requests.IsEmpty() {
- panic(c.requestState.Requests.GetCardinality())
- }
-}
-
-func (c *Peer) cancelAllRequests() {
- c.requestState.Requests.IterateSnapshot(func(x RequestIndex) bool {
- c.cancel(x)
- return true
- })
- c.assertNoRequests()
- return
-}
-
// This is called when something has changed that should wake the writer, such as putting stuff into
// the writeBuffer, or changing some state that the writer can act on.
func (c *PeerConn) tickleWriter() {
t.reconcileHandshakeStats(c)
}
-func (c *Peer) peerPriority() (peerPriority, error) {
- return bep40Priority(c.remoteIpPort(), c.localPublicAddr)
-}
-
-func (c *Peer) remoteIp() net.IP {
- host, _, _ := net.SplitHostPort(c.RemoteAddr.String())
- return net.ParseIP(host)
-}
-
-func (c *Peer) remoteIpPort() IpPort {
- ipa, _ := tryIpPortFromNetAddr(c.RemoteAddr)
- return IpPort{ipa.IP, uint16(ipa.Port)}
-}
-
func (c *PeerConn) pexPeerFlags() pp.PexPeerFlags {
f := pp.PexPeerFlags(0)
if c.PeerPrefersEncryption {
return fmt.Sprintf("%T %p [id=%q, exts=%v, v=%q]", c, c, c.PeerID, c.PeerExtensionBytes, c.PeerClientName.Load())
}
-func (c *Peer) trust() connectionTrust {
- return connectionTrust{c.trusted, c.netGoodPiecesDirtied()}
-}
-
-type connectionTrust struct {
- Implicit bool
- NetGoodPiecesDirted int64
-}
-
-func (l connectionTrust) Less(r connectionTrust) bool {
- return multiless.New().Bool(l.Implicit, r.Implicit).Int64(l.NetGoodPiecesDirted, r.NetGoodPiecesDirted).Less()
-}
-
// Returns the pieces the peer could have based on their claims. If we don't know how many pieces
// are in the torrent, it could be a very large range the peer has sent HaveAll.
func (cn *PeerConn) PeerPieces() *roaring.Bitmap {
return cn.newPeerPieces()
}
-// Returns a new Bitmap that includes bits for all pieces the peer could have based on their claims.
-func (cn *Peer) newPeerPieces() *roaring.Bitmap {
- // TODO: Can we use copy on write?
- ret := cn.peerPieces().Clone()
- if all, _ := cn.peerHasAllPieces(); all {
- if cn.t.haveInfo() {
- ret.AddRange(0, bitmap.BitRange(cn.t.numPieces()))
- } else {
- ret.AddRange(0, bitmap.ToEnd)
- }
- }
- return ret
-}
-
-func (cn *Peer) stats() *ConnStats {
- return &cn._stats
-}
-
-func (p *Peer) TryAsPeerConn() (*PeerConn, bool) {
- pc, ok := p.peerImpl.(*PeerConn)
- return pc, ok
-}
-
-func (p *Peer) uncancelledRequests() uint64 {
- return p.requestState.Requests.GetCardinality()
-}
-
func (pc *PeerConn) remoteIsTransmission() bool {
return bytes.HasPrefix(pc.PeerID[:], []byte("-TR")) && pc.PeerID[7] == '-'
}