status-go/vendor/github.com/anacrolix/torrent/client.go

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2022-03-10 09:44:48 +00:00
package torrent
import (
"bufio"
"context"
"crypto/rand"
"encoding/binary"
"errors"
"expvar"
"fmt"
"io"
"math"
"net"
"net/http"
"sort"
"strconv"
"strings"
"time"
"github.com/anacrolix/chansync/events"
"github.com/anacrolix/dht/v2"
"github.com/anacrolix/dht/v2/krpc"
"github.com/anacrolix/log"
"github.com/anacrolix/missinggo/perf"
"github.com/anacrolix/missinggo/pubsub"
"github.com/anacrolix/missinggo/v2"
"github.com/anacrolix/missinggo/v2/bitmap"
"github.com/anacrolix/missinggo/v2/pproffd"
"github.com/anacrolix/sync"
request_strategy "github.com/anacrolix/torrent/request-strategy"
"github.com/davecgh/go-spew/spew"
"github.com/dustin/go-humanize"
"github.com/google/btree"
"github.com/pion/datachannel"
"golang.org/x/time/rate"
"github.com/anacrolix/chansync"
"github.com/anacrolix/torrent/bencode"
"github.com/anacrolix/torrent/internal/limiter"
"github.com/anacrolix/torrent/iplist"
"github.com/anacrolix/torrent/metainfo"
"github.com/anacrolix/torrent/mse"
pp "github.com/anacrolix/torrent/peer_protocol"
"github.com/anacrolix/torrent/storage"
"github.com/anacrolix/torrent/tracker"
"github.com/anacrolix/torrent/webtorrent"
)
// Clients contain zero or more Torrents. A Client manages a blocklist, the
// TCP/UDP protocol ports, and DHT as desired.
type Client struct {
// An aggregate of stats over all connections. First in struct to ensure 64-bit alignment of
// fields. See #262.
stats ConnStats
_mu lockWithDeferreds
event sync.Cond
closed chansync.SetOnce
config *ClientConfig
logger log.Logger
peerID PeerID
defaultStorage *storage.Client
onClose []func()
dialers []Dialer
listeners []Listener
dhtServers []DhtServer
ipBlockList iplist.Ranger
// Set of addresses that have our client ID. This intentionally will
// include ourselves if we end up trying to connect to our own address
// through legitimate channels.
dopplegangerAddrs map[string]struct{}
badPeerIPs map[string]struct{}
torrents map[InfoHash]*Torrent
pieceRequestOrder map[interface{}]*request_strategy.PieceRequestOrder
acceptLimiter map[ipStr]int
dialRateLimiter *rate.Limiter
numHalfOpen int
websocketTrackers websocketTrackers
activeAnnounceLimiter limiter.Instance
webseedHttpClient *http.Client
}
type ipStr string
func (cl *Client) BadPeerIPs() (ips []string) {
cl.rLock()
ips = cl.badPeerIPsLocked()
cl.rUnlock()
return
}
func (cl *Client) badPeerIPsLocked() (ips []string) {
ips = make([]string, len(cl.badPeerIPs))
i := 0
for k := range cl.badPeerIPs {
ips[i] = k
i += 1
}
return
}
func (cl *Client) PeerID() PeerID {
return cl.peerID
}
// Returns the port number for the first listener that has one. No longer assumes that all port
// numbers are the same, due to support for custom listeners. Returns zero if no port number is
// found.
func (cl *Client) LocalPort() (port int) {
for i := 0; i < len(cl.listeners); i += 1 {
if port = addrPortOrZero(cl.listeners[i].Addr()); port != 0 {
return
}
}
return
}
func writeDhtServerStatus(w io.Writer, s DhtServer) {
dhtStats := s.Stats()
fmt.Fprintf(w, " ID: %x\n", s.ID())
spew.Fdump(w, dhtStats)
}
// Writes out a human readable status of the client, such as for writing to a
// HTTP status page.
func (cl *Client) WriteStatus(_w io.Writer) {
cl.rLock()
defer cl.rUnlock()
w := bufio.NewWriter(_w)
defer w.Flush()
fmt.Fprintf(w, "Listen port: %d\n", cl.LocalPort())
fmt.Fprintf(w, "Peer ID: %+q\n", cl.PeerID())
fmt.Fprintf(w, "Extension bits: %v\n", cl.config.Extensions)
fmt.Fprintf(w, "Announce key: %x\n", cl.announceKey())
fmt.Fprintf(w, "Banned IPs: %d\n", len(cl.badPeerIPsLocked()))
cl.eachDhtServer(func(s DhtServer) {
fmt.Fprintf(w, "%s DHT server at %s:\n", s.Addr().Network(), s.Addr().String())
writeDhtServerStatus(w, s)
})
spew.Fdump(w, &cl.stats)
torrentsSlice := cl.torrentsAsSlice()
fmt.Fprintf(w, "# Torrents: %d\n", len(torrentsSlice))
fmt.Fprintln(w)
sort.Slice(torrentsSlice, func(l, r int) bool {
return torrentsSlice[l].infoHash.AsString() < torrentsSlice[r].infoHash.AsString()
})
for _, t := range torrentsSlice {
if t.name() == "" {
fmt.Fprint(w, "<unknown name>")
} else {
fmt.Fprint(w, t.name())
}
fmt.Fprint(w, "\n")
if t.info != nil {
fmt.Fprintf(
w,
"%f%% of %d bytes (%s)",
100*(1-float64(t.bytesMissingLocked())/float64(t.info.TotalLength())),
*t.length,
humanize.Bytes(uint64(*t.length)))
} else {
w.WriteString("<missing metainfo>")
}
fmt.Fprint(w, "\n")
t.writeStatus(w)
fmt.Fprintln(w)
}
}
func (cl *Client) initLogger() {
logger := cl.config.Logger
if logger.IsZero() {
logger = log.Default
}
if cl.config.Debug {
logger = logger.FilterLevel(log.Debug)
}
cl.logger = logger.WithValues(cl)
}
func (cl *Client) announceKey() int32 {
return int32(binary.BigEndian.Uint32(cl.peerID[16:20]))
}
// Initializes a bare minimum Client. *Client and *ClientConfig must not be nil.
func (cl *Client) init(cfg *ClientConfig) {
cl.config = cfg
cl.dopplegangerAddrs = make(map[string]struct{})
cl.torrents = make(map[metainfo.Hash]*Torrent)
cl.dialRateLimiter = rate.NewLimiter(10, 10)
cl.activeAnnounceLimiter.SlotsPerKey = 2
cl.event.L = cl.locker()
cl.ipBlockList = cfg.IPBlocklist
cl.webseedHttpClient = &http.Client{
Transport: &http.Transport{
Proxy: cfg.HTTPProxy,
MaxConnsPerHost: 10,
},
}
}
func NewClient(cfg *ClientConfig) (cl *Client, err error) {
if cfg == nil {
cfg = NewDefaultClientConfig()
cfg.ListenPort = 0
}
var client Client
client.init(cfg)
cl = &client
go cl.acceptLimitClearer()
cl.initLogger()
defer func() {
if err != nil {
cl.Close()
cl = nil
}
}()
storageImpl := cfg.DefaultStorage
if storageImpl == nil {
// We'd use mmap by default but HFS+ doesn't support sparse files.
storageImplCloser := storage.NewFile(cfg.DataDir)
cl.onClose = append(cl.onClose, func() {
if err := storageImplCloser.Close(); err != nil {
cl.logger.Printf("error closing default storage: %s", err)
}
})
storageImpl = storageImplCloser
}
cl.defaultStorage = storage.NewClient(storageImpl)
if cfg.PeerID != "" {
missinggo.CopyExact(&cl.peerID, cfg.PeerID)
} else {
o := copy(cl.peerID[:], cfg.Bep20)
_, err = rand.Read(cl.peerID[o:])
if err != nil {
panic("error generating peer id")
}
}
sockets, err := listenAll(cl.listenNetworks(), cl.config.ListenHost, cl.config.ListenPort, cl.firewallCallback, cl.logger)
if err != nil {
return
}
// Check for panics.
cl.LocalPort()
for _, _s := range sockets {
s := _s // Go is fucking retarded.
cl.onClose = append(cl.onClose, func() { go s.Close() })
if peerNetworkEnabled(parseNetworkString(s.Addr().Network()), cl.config) {
cl.dialers = append(cl.dialers, s)
cl.listeners = append(cl.listeners, s)
if cl.config.AcceptPeerConnections {
go cl.acceptConnections(s)
}
}
}
go cl.forwardPort()
if !cfg.NoDHT {
for _, s := range sockets {
if pc, ok := s.(net.PacketConn); ok {
ds, err := cl.NewAnacrolixDhtServer(pc)
if err != nil {
panic(err)
}
cl.dhtServers = append(cl.dhtServers, AnacrolixDhtServerWrapper{ds})
cl.onClose = append(cl.onClose, func() { ds.Close() })
}
}
}
cl.websocketTrackers = websocketTrackers{
PeerId: cl.peerID,
Logger: cl.logger,
GetAnnounceRequest: func(event tracker.AnnounceEvent, infoHash [20]byte) (tracker.AnnounceRequest, error) {
cl.lock()
defer cl.unlock()
t, ok := cl.torrents[infoHash]
if !ok {
return tracker.AnnounceRequest{}, errors.New("torrent not tracked by client")
}
return t.announceRequest(event), nil
},
Proxy: cl.config.HTTPProxy,
OnConn: func(dc datachannel.ReadWriteCloser, dcc webtorrent.DataChannelContext) {
cl.lock()
defer cl.unlock()
t, ok := cl.torrents[dcc.InfoHash]
if !ok {
cl.logger.WithDefaultLevel(log.Warning).Printf(
"got webrtc conn for unloaded torrent with infohash %x",
dcc.InfoHash,
)
dc.Close()
return
}
go t.onWebRtcConn(dc, dcc)
},
}
return
}
func (cl *Client) AddDhtServer(d DhtServer) {
cl.dhtServers = append(cl.dhtServers, d)
}
// Adds a Dialer for outgoing connections. All Dialers are used when attempting to connect to a
// given address for any Torrent.
func (cl *Client) AddDialer(d Dialer) {
cl.lock()
defer cl.unlock()
cl.dialers = append(cl.dialers, d)
for _, t := range cl.torrents {
t.openNewConns()
}
}
func (cl *Client) Listeners() []Listener {
return cl.listeners
}
// Registers a Listener, and starts Accepting on it. You must Close Listeners provided this way
// yourself.
func (cl *Client) AddListener(l Listener) {
cl.listeners = append(cl.listeners, l)
if cl.config.AcceptPeerConnections {
go cl.acceptConnections(l)
}
}
func (cl *Client) firewallCallback(net.Addr) bool {
cl.rLock()
block := !cl.wantConns() || !cl.config.AcceptPeerConnections
cl.rUnlock()
if block {
torrent.Add("connections firewalled", 1)
} else {
torrent.Add("connections not firewalled", 1)
}
return block
}
func (cl *Client) listenOnNetwork(n network) bool {
if n.Ipv4 && cl.config.DisableIPv4 {
return false
}
if n.Ipv6 && cl.config.DisableIPv6 {
return false
}
if n.Tcp && cl.config.DisableTCP {
return false
}
if n.Udp && cl.config.DisableUTP && cl.config.NoDHT {
return false
}
return true
}
func (cl *Client) listenNetworks() (ns []network) {
for _, n := range allPeerNetworks {
if cl.listenOnNetwork(n) {
ns = append(ns, n)
}
}
return
}
// Creates an anacrolix/dht Server, as would be done internally in NewClient, for the given conn.
func (cl *Client) NewAnacrolixDhtServer(conn net.PacketConn) (s *dht.Server, err error) {
cfg := dht.ServerConfig{
IPBlocklist: cl.ipBlockList,
Conn: conn,
OnAnnouncePeer: cl.onDHTAnnouncePeer,
PublicIP: func() net.IP {
if connIsIpv6(conn) && cl.config.PublicIp6 != nil {
return cl.config.PublicIp6
}
return cl.config.PublicIp4
}(),
StartingNodes: cl.config.DhtStartingNodes(conn.LocalAddr().Network()),
OnQuery: cl.config.DHTOnQuery,
Logger: cl.logger.WithContextText(fmt.Sprintf("dht server on %v", conn.LocalAddr().String())),
}
if f := cl.config.ConfigureAnacrolixDhtServer; f != nil {
f(&cfg)
}
s, err = dht.NewServer(&cfg)
if err == nil {
go func() {
ts, err := s.Bootstrap()
if err != nil {
cl.logger.Printf("error bootstrapping dht: %s", err)
}
log.Fstr("%v completed bootstrap (%+v)", s, ts).AddValues(s, ts).Log(cl.logger)
}()
}
return
}
func (cl *Client) Closed() events.Done {
return cl.closed.Done()
}
func (cl *Client) eachDhtServer(f func(DhtServer)) {
for _, ds := range cl.dhtServers {
f(ds)
}
}
// Stops the client. All connections to peers are closed and all activity will come to a halt.
func (cl *Client) Close() (errs []error) {
var closeGroup sync.WaitGroup // For concurrent cleanup to complete before returning
cl.lock()
for _, t := range cl.torrents {
err := t.close(&closeGroup)
if err != nil {
errs = append(errs, err)
}
}
for i := range cl.onClose {
cl.onClose[len(cl.onClose)-1-i]()
}
cl.closed.Set()
cl.unlock()
cl.event.Broadcast()
closeGroup.Wait() // defer is LIFO. We want to Wait() after cl.unlock()
return
}
func (cl *Client) ipBlockRange(ip net.IP) (r iplist.Range, blocked bool) {
if cl.ipBlockList == nil {
return
}
return cl.ipBlockList.Lookup(ip)
}
func (cl *Client) ipIsBlocked(ip net.IP) bool {
_, blocked := cl.ipBlockRange(ip)
return blocked
}
func (cl *Client) wantConns() bool {
if cl.config.AlwaysWantConns {
return true
}
for _, t := range cl.torrents {
if t.wantConns() {
return true
}
}
return false
}
// TODO: Apply filters for non-standard networks, particularly rate-limiting.
func (cl *Client) rejectAccepted(conn net.Conn) error {
if !cl.wantConns() {
return errors.New("don't want conns right now")
}
ra := conn.RemoteAddr()
if rip := addrIpOrNil(ra); rip != nil {
if cl.config.DisableIPv4Peers && rip.To4() != nil {
return errors.New("ipv4 peers disabled")
}
if cl.config.DisableIPv4 && len(rip) == net.IPv4len {
return errors.New("ipv4 disabled")
}
if cl.config.DisableIPv6 && len(rip) == net.IPv6len && rip.To4() == nil {
return errors.New("ipv6 disabled")
}
if cl.rateLimitAccept(rip) {
return errors.New("source IP accepted rate limited")
}
if cl.badPeerIPPort(rip, missinggo.AddrPort(ra)) {
return errors.New("bad source addr")
}
}
return nil
}
func (cl *Client) acceptConnections(l Listener) {
for {
conn, err := l.Accept()
torrent.Add("client listener accepts", 1)
conn = pproffd.WrapNetConn(conn)
cl.rLock()
closed := cl.closed.IsSet()
var reject error
if !closed && conn != nil {
reject = cl.rejectAccepted(conn)
}
cl.rUnlock()
if closed {
if conn != nil {
conn.Close()
}
return
}
if err != nil {
log.Fmsg("error accepting connection: %s", err).LogLevel(log.Debug, cl.logger)
continue
}
go func() {
if reject != nil {
torrent.Add("rejected accepted connections", 1)
cl.logger.LazyLog(log.Debug, func() log.Msg {
return log.Fmsg("rejecting accepted conn: %v", reject)
})
conn.Close()
} else {
go cl.incomingConnection(conn)
}
cl.logger.LazyLog(log.Debug, func() log.Msg {
return log.Fmsg("accepted %q connection at %q from %q",
l.Addr().Network(),
conn.LocalAddr(),
conn.RemoteAddr(),
)
})
torrent.Add(fmt.Sprintf("accepted conn remote IP len=%d", len(addrIpOrNil(conn.RemoteAddr()))), 1)
torrent.Add(fmt.Sprintf("accepted conn network=%s", conn.RemoteAddr().Network()), 1)
torrent.Add(fmt.Sprintf("accepted on %s listener", l.Addr().Network()), 1)
}()
}
}
// Creates the PeerConn.connString for a regular net.Conn PeerConn.
func regularNetConnPeerConnConnString(nc net.Conn) string {
return fmt.Sprintf("%s-%s", nc.LocalAddr(), nc.RemoteAddr())
}
func (cl *Client) incomingConnection(nc net.Conn) {
defer nc.Close()
if tc, ok := nc.(*net.TCPConn); ok {
tc.SetLinger(0)
}
c := cl.newConnection(nc, false, nc.RemoteAddr(), nc.RemoteAddr().Network(),
regularNetConnPeerConnConnString(nc))
defer func() {
cl.lock()
defer cl.unlock()
c.close()
}()
c.Discovery = PeerSourceIncoming
cl.runReceivedConn(c)
}
// Returns a handle to the given torrent, if it's present in the client.
func (cl *Client) Torrent(ih metainfo.Hash) (t *Torrent, ok bool) {
cl.lock()
defer cl.unlock()
t, ok = cl.torrents[ih]
return
}
func (cl *Client) torrent(ih metainfo.Hash) *Torrent {
return cl.torrents[ih]
}
type DialResult struct {
Conn net.Conn
Dialer Dialer
}
func countDialResult(err error) {
if err == nil {
torrent.Add("successful dials", 1)
} else {
torrent.Add("unsuccessful dials", 1)
}
}
func reducedDialTimeout(minDialTimeout, max time.Duration, halfOpenLimit, pendingPeers int) (ret time.Duration) {
ret = max / time.Duration((pendingPeers+halfOpenLimit)/halfOpenLimit)
if ret < minDialTimeout {
ret = minDialTimeout
}
return
}
// Returns whether an address is known to connect to a client with our own ID.
func (cl *Client) dopplegangerAddr(addr string) bool {
_, ok := cl.dopplegangerAddrs[addr]
return ok
}
// Returns a connection over UTP or TCP, whichever is first to connect.
func (cl *Client) dialFirst(ctx context.Context, addr string) (res DialResult) {
return DialFirst(ctx, addr, cl.dialers)
}
// Returns a connection over UTP or TCP, whichever is first to connect.
func DialFirst(ctx context.Context, addr string, dialers []Dialer) (res DialResult) {
{
t := perf.NewTimer(perf.CallerName(0))
defer func() {
if res.Conn == nil {
t.Mark(fmt.Sprintf("returned no conn (context: %v)", ctx.Err()))
} else {
t.Mark("returned conn over " + res.Dialer.DialerNetwork())
}
}()
}
ctx, cancel := context.WithCancel(ctx)
// As soon as we return one connection, cancel the others.
defer cancel()
left := 0
resCh := make(chan DialResult, left)
for _, _s := range dialers {
left++
s := _s
go func() {
resCh <- DialResult{
dialFromSocket(ctx, s, addr),
s,
}
}()
}
// Wait for a successful connection.
func() {
defer perf.ScopeTimer()()
for ; left > 0 && res.Conn == nil; left-- {
res = <-resCh
}
}()
// There are still incompleted dials.
go func() {
for ; left > 0; left-- {
conn := (<-resCh).Conn
if conn != nil {
conn.Close()
}
}
}()
if res.Conn != nil {
go torrent.Add(fmt.Sprintf("network dialed first: %s", res.Conn.RemoteAddr().Network()), 1)
}
return res
}
func dialFromSocket(ctx context.Context, s Dialer, addr string) net.Conn {
c, err := s.Dial(ctx, addr)
// This is a bit optimistic, but it looks non-trivial to thread this through the proxy code. Set
// it now in case we close the connection forthwith.
if tc, ok := c.(*net.TCPConn); ok {
tc.SetLinger(0)
}
countDialResult(err)
return c
}
func forgettableDialError(err error) bool {
return strings.Contains(err.Error(), "no suitable address found")
}
func (cl *Client) noLongerHalfOpen(t *Torrent, addr string) {
if _, ok := t.halfOpen[addr]; !ok {
panic("invariant broken")
}
delete(t.halfOpen, addr)
cl.numHalfOpen--
for _, t := range cl.torrents {
t.openNewConns()
}
}
// Performs initiator handshakes and returns a connection. Returns nil *connection if no connection
// for valid reasons.
func (cl *Client) initiateProtocolHandshakes(
ctx context.Context,
nc net.Conn,
t *Torrent,
outgoing, encryptHeader bool,
remoteAddr PeerRemoteAddr,
network, connString string,
) (
c *PeerConn, err error,
) {
c = cl.newConnection(nc, outgoing, remoteAddr, network, connString)
c.headerEncrypted = encryptHeader
ctx, cancel := context.WithTimeout(ctx, cl.config.HandshakesTimeout)
defer cancel()
dl, ok := ctx.Deadline()
if !ok {
panic(ctx)
}
err = nc.SetDeadline(dl)
if err != nil {
panic(err)
}
err = cl.initiateHandshakes(c, t)
return
}
// Returns nil connection and nil error if no connection could be established for valid reasons.
func (cl *Client) establishOutgoingConnEx(t *Torrent, addr PeerRemoteAddr, obfuscatedHeader bool) (*PeerConn, error) {
dialCtx, cancel := context.WithTimeout(context.Background(), func() time.Duration {
cl.rLock()
defer cl.rUnlock()
return t.dialTimeout()
}())
defer cancel()
dr := cl.dialFirst(dialCtx, addr.String())
nc := dr.Conn
if nc == nil {
if dialCtx.Err() != nil {
return nil, fmt.Errorf("dialing: %w", dialCtx.Err())
}
return nil, errors.New("dial failed")
}
c, err := cl.initiateProtocolHandshakes(context.Background(), nc, t, true, obfuscatedHeader, addr, dr.Dialer.DialerNetwork(), regularNetConnPeerConnConnString(nc))
if err != nil {
nc.Close()
}
return c, err
}
// Returns nil connection and nil error if no connection could be established
// for valid reasons.
func (cl *Client) establishOutgoingConn(t *Torrent, addr PeerRemoteAddr) (c *PeerConn, err error) {
torrent.Add("establish outgoing connection", 1)
obfuscatedHeaderFirst := cl.config.HeaderObfuscationPolicy.Preferred
c, err = cl.establishOutgoingConnEx(t, addr, obfuscatedHeaderFirst)
if err == nil {
torrent.Add("initiated conn with preferred header obfuscation", 1)
return
}
// cl.logger.Printf("error establishing connection to %s (obfuscatedHeader=%t): %v", addr, obfuscatedHeaderFirst, err)
if cl.config.HeaderObfuscationPolicy.RequirePreferred {
// We should have just tried with the preferred header obfuscation. If it was required,
// there's nothing else to try.
return
}
// Try again with encryption if we didn't earlier, or without if we did.
c, err = cl.establishOutgoingConnEx(t, addr, !obfuscatedHeaderFirst)
if err == nil {
torrent.Add("initiated conn with fallback header obfuscation", 1)
}
// cl.logger.Printf("error establishing fallback connection to %v: %v", addr, err)
return
}
// Called to dial out and run a connection. The addr we're given is already
// considered half-open.
func (cl *Client) outgoingConnection(t *Torrent, addr PeerRemoteAddr, ps PeerSource, trusted bool) {
cl.dialRateLimiter.Wait(context.Background())
c, err := cl.establishOutgoingConn(t, addr)
if err == nil {
c.conn.SetWriteDeadline(time.Time{})
}
cl.lock()
defer cl.unlock()
// Don't release lock between here and addPeerConn, unless it's for
// failure.
cl.noLongerHalfOpen(t, addr.String())
if err != nil {
if cl.config.Debug {
cl.logger.Printf("error establishing outgoing connection to %v: %v", addr, err)
}
return
}
defer c.close()
c.Discovery = ps
c.trusted = trusted
t.runHandshookConnLoggingErr(c)
}
// The port number for incoming peer connections. 0 if the client isn't listening.
func (cl *Client) incomingPeerPort() int {
return cl.LocalPort()
}
func (cl *Client) initiateHandshakes(c *PeerConn, t *Torrent) error {
if c.headerEncrypted {
var rw io.ReadWriter
var err error
rw, c.cryptoMethod, err = mse.InitiateHandshake(
struct {
io.Reader
io.Writer
}{c.r, c.w},
t.infoHash[:],
nil,
cl.config.CryptoProvides,
)
c.setRW(rw)
if err != nil {
return fmt.Errorf("header obfuscation handshake: %w", err)
}
}
ih, err := cl.connBtHandshake(c, &t.infoHash)
if err != nil {
return fmt.Errorf("bittorrent protocol handshake: %w", err)
}
if ih != t.infoHash {
return errors.New("bittorrent protocol handshake: peer infohash didn't match")
}
return nil
}
// Calls f with any secret keys. Note that it takes the Client lock, and so must be used from code
// that won't also try to take the lock. This saves us copying all the infohashes everytime.
func (cl *Client) forSkeys(f func([]byte) bool) {
cl.rLock()
defer cl.rUnlock()
if false { // Emulate the bug from #114
var firstIh InfoHash
for ih := range cl.torrents {
firstIh = ih
break
}
for range cl.torrents {
if !f(firstIh[:]) {
break
}
}
return
}
for ih := range cl.torrents {
if !f(ih[:]) {
break
}
}
}
func (cl *Client) handshakeReceiverSecretKeys() mse.SecretKeyIter {
if ret := cl.config.Callbacks.ReceiveEncryptedHandshakeSkeys; ret != nil {
return ret
}
return cl.forSkeys
}
// Do encryption and bittorrent handshakes as receiver.
func (cl *Client) receiveHandshakes(c *PeerConn) (t *Torrent, err error) {
defer perf.ScopeTimerErr(&err)()
var rw io.ReadWriter
rw, c.headerEncrypted, c.cryptoMethod, err = handleEncryption(c.rw(), cl.handshakeReceiverSecretKeys(), cl.config.HeaderObfuscationPolicy, cl.config.CryptoSelector)
c.setRW(rw)
if err == nil || err == mse.ErrNoSecretKeyMatch {
if c.headerEncrypted {
torrent.Add("handshakes received encrypted", 1)
} else {
torrent.Add("handshakes received unencrypted", 1)
}
} else {
torrent.Add("handshakes received with error while handling encryption", 1)
}
if err != nil {
if err == mse.ErrNoSecretKeyMatch {
err = nil
}
return
}
if cl.config.HeaderObfuscationPolicy.RequirePreferred && c.headerEncrypted != cl.config.HeaderObfuscationPolicy.Preferred {
err = errors.New("connection does not have required header obfuscation")
return
}
ih, err := cl.connBtHandshake(c, nil)
if err != nil {
return nil, fmt.Errorf("during bt handshake: %w", err)
}
cl.lock()
t = cl.torrents[ih]
cl.unlock()
return
}
var successfulPeerWireProtocolHandshakePeerReservedBytes expvar.Map
func init() {
torrent.Set(
"successful_peer_wire_protocol_handshake_peer_reserved_bytes",
&successfulPeerWireProtocolHandshakePeerReservedBytes)
}
func (cl *Client) connBtHandshake(c *PeerConn, ih *metainfo.Hash) (ret metainfo.Hash, err error) {
res, err := pp.Handshake(c.rw(), ih, cl.peerID, cl.config.Extensions)
if err != nil {
return
}
successfulPeerWireProtocolHandshakePeerReservedBytes.Add(res.PeerExtensionBits.String(), 1)
ret = res.Hash
c.PeerExtensionBytes = res.PeerExtensionBits
c.PeerID = res.PeerID
c.completedHandshake = time.Now()
if cb := cl.config.Callbacks.CompletedHandshake; cb != nil {
cb(c, res.Hash)
}
return
}
func (cl *Client) runReceivedConn(c *PeerConn) {
err := c.conn.SetDeadline(time.Now().Add(cl.config.HandshakesTimeout))
if err != nil {
panic(err)
}
t, err := cl.receiveHandshakes(c)
if err != nil {
cl.logger.LazyLog(log.Debug, func() log.Msg {
return log.Fmsg(
"error receiving handshakes on %v: %s", c, err,
).Add(
"network", c.Network,
)
})
torrent.Add("error receiving handshake", 1)
cl.lock()
cl.onBadAccept(c.RemoteAddr)
cl.unlock()
return
}
if t == nil {
torrent.Add("received handshake for unloaded torrent", 1)
cl.logger.LazyLog(log.Debug, func() log.Msg {
return log.Fmsg("received handshake for unloaded torrent")
})
cl.lock()
cl.onBadAccept(c.RemoteAddr)
cl.unlock()
return
}
torrent.Add("received handshake for loaded torrent", 1)
c.conn.SetWriteDeadline(time.Time{})
cl.lock()
defer cl.unlock()
t.runHandshookConnLoggingErr(c)
}
// Client lock must be held before entering this.
func (cl *Client) runHandshookConn(c *PeerConn, t *Torrent) error {
c.setTorrent(t)
for i, b := range cl.config.MinPeerExtensions {
if c.PeerExtensionBytes[i]&b != b {
return fmt.Errorf("peer did not meet minimum peer extensions: %x", c.PeerExtensionBytes[:])
}
}
if c.PeerID == cl.peerID {
if c.outgoing {
connsToSelf.Add(1)
addr := c.RemoteAddr.String()
cl.dopplegangerAddrs[addr] = struct{}{}
} /* else {
// Because the remote address is not necessarily the same as its client's torrent listen
// address, we won't record the remote address as a doppleganger. Instead, the initiator
// can record *us* as the doppleganger.
} */
t.logger.Levelf(log.Debug, "local and remote peer ids are the same")
return nil
}
c.r = deadlineReader{c.conn, c.r}
completedHandshakeConnectionFlags.Add(c.connectionFlags(), 1)
if connIsIpv6(c.conn) {
torrent.Add("completed handshake over ipv6", 1)
}
if err := t.addPeerConn(c); err != nil {
return fmt.Errorf("adding connection: %w", err)
}
defer t.dropConnection(c)
c.startWriter()
cl.sendInitialMessages(c, t)
c.initUpdateRequestsTimer()
err := c.mainReadLoop()
if err != nil {
return fmt.Errorf("main read loop: %w", err)
}
return nil
}
const check = false
func (p *Peer) initUpdateRequestsTimer() {
if check {
if p.updateRequestsTimer != nil {
panic(p.updateRequestsTimer)
}
}
p.updateRequestsTimer = time.AfterFunc(math.MaxInt64, p.updateRequestsTimerFunc)
}
const peerUpdateRequestsTimerReason = "updateRequestsTimer"
func (c *Peer) updateRequestsTimerFunc() {
c.locker().Lock()
defer c.locker().Unlock()
if c.closed.IsSet() {
return
}
if c.isLowOnRequests() {
// If there are no outstanding requests, then a request update should have already run.
return
}
if d := time.Since(c.lastRequestUpdate); d < updateRequestsTimerDuration {
// These should be benign, Timer.Stop doesn't guarantee that its function won't run if it's
// already been fired.
torrent.Add("spurious timer requests updates", 1)
return
}
c.updateRequests(peerUpdateRequestsTimerReason)
}
// Maximum pending requests we allow peers to send us. If peer requests are buffered on read, this
// instructs the amount of memory that might be used to cache pending writes. Assuming 512KiB
// (1<<19) cached for sending, for 16KiB (1<<14) chunks.
const localClientReqq = 1 << 5
// See the order given in Transmission's tr_peerMsgsNew.
func (cl *Client) sendInitialMessages(conn *PeerConn, torrent *Torrent) {
if conn.PeerExtensionBytes.SupportsExtended() && cl.config.Extensions.SupportsExtended() {
conn.write(pp.Message{
Type: pp.Extended,
ExtendedID: pp.HandshakeExtendedID,
ExtendedPayload: func() []byte {
msg := pp.ExtendedHandshakeMessage{
M: map[pp.ExtensionName]pp.ExtensionNumber{
pp.ExtensionNameMetadata: metadataExtendedId,
},
V: cl.config.ExtendedHandshakeClientVersion,
Reqq: localClientReqq,
YourIp: pp.CompactIp(conn.remoteIp()),
Encryption: cl.config.HeaderObfuscationPolicy.Preferred || !cl.config.HeaderObfuscationPolicy.RequirePreferred,
Port: cl.incomingPeerPort(),
MetadataSize: torrent.metadataSize(),
// TODO: We can figured these out specific to the socket
// used.
Ipv4: pp.CompactIp(cl.config.PublicIp4.To4()),
Ipv6: cl.config.PublicIp6.To16(),
}
if !cl.config.DisablePEX {
msg.M[pp.ExtensionNamePex] = pexExtendedId
}
return bencode.MustMarshal(msg)
}(),
})
}
func() {
if conn.fastEnabled() {
if torrent.haveAllPieces() {
conn.write(pp.Message{Type: pp.HaveAll})
conn.sentHaves.AddRange(0, bitmap.BitRange(conn.t.NumPieces()))
return
} else if !torrent.haveAnyPieces() {
conn.write(pp.Message{Type: pp.HaveNone})
conn.sentHaves.Clear()
return
}
}
conn.postBitfield()
}()
if conn.PeerExtensionBytes.SupportsDHT() && cl.config.Extensions.SupportsDHT() && cl.haveDhtServer() {
conn.write(pp.Message{
Type: pp.Port,
Port: cl.dhtPort(),
})
}
}
func (cl *Client) dhtPort() (ret uint16) {
if len(cl.dhtServers) == 0 {
return
}
return uint16(missinggo.AddrPort(cl.dhtServers[len(cl.dhtServers)-1].Addr()))
}
func (cl *Client) haveDhtServer() bool {
return len(cl.dhtServers) > 0
}
// Process incoming ut_metadata message.
func (cl *Client) gotMetadataExtensionMsg(payload []byte, t *Torrent, c *PeerConn) error {
var d pp.ExtendedMetadataRequestMsg
err := bencode.Unmarshal(payload, &d)
if _, ok := err.(bencode.ErrUnusedTrailingBytes); ok {
} else if err != nil {
return fmt.Errorf("error unmarshalling bencode: %s", err)
}
piece := d.Piece
switch d.Type {
case pp.DataMetadataExtensionMsgType:
c.allStats(add(1, func(cs *ConnStats) *Count { return &cs.MetadataChunksRead }))
if !c.requestedMetadataPiece(piece) {
return fmt.Errorf("got unexpected piece %d", piece)
}
c.metadataRequests[piece] = false
begin := len(payload) - d.PieceSize()
if begin < 0 || begin >= len(payload) {
return fmt.Errorf("data has bad offset in payload: %d", begin)
}
t.saveMetadataPiece(piece, payload[begin:])
c.lastUsefulChunkReceived = time.Now()
err = t.maybeCompleteMetadata()
if err != nil {
// Log this at the Torrent-level, as we don't partition metadata by Peer yet, so we
// don't know who to blame. TODO: Also errors can be returned here that aren't related
// to verifying metadata, which should be fixed. This should be tagged with metadata, so
// log consumers can filter for this message.
t.logger.WithDefaultLevel(log.Warning).Printf("error completing metadata: %v", err)
}
return err
case pp.RequestMetadataExtensionMsgType:
if !t.haveMetadataPiece(piece) {
c.write(t.newMetadataExtensionMessage(c, pp.RejectMetadataExtensionMsgType, d.Piece, nil))
return nil
}
start := (1 << 14) * piece
c.logger.WithDefaultLevel(log.Debug).Printf("sending metadata piece %d", piece)
c.write(t.newMetadataExtensionMessage(c, pp.DataMetadataExtensionMsgType, piece, t.metadataBytes[start:start+t.metadataPieceSize(piece)]))
return nil
case pp.RejectMetadataExtensionMsgType:
return nil
default:
return errors.New("unknown msg_type value")
}
}
func (cl *Client) badPeerAddr(addr PeerRemoteAddr) bool {
if ipa, ok := tryIpPortFromNetAddr(addr); ok {
return cl.badPeerIPPort(ipa.IP, ipa.Port)
}
return false
}
func (cl *Client) badPeerIPPort(ip net.IP, port int) bool {
if port == 0 {
return true
}
if cl.dopplegangerAddr(net.JoinHostPort(ip.String(), strconv.FormatInt(int64(port), 10))) {
return true
}
if _, ok := cl.ipBlockRange(ip); ok {
return true
}
if _, ok := cl.badPeerIPs[ip.String()]; ok {
return true
}
return false
}
// Return a Torrent ready for insertion into a Client.
func (cl *Client) newTorrent(ih metainfo.Hash, specStorage storage.ClientImpl) (t *Torrent) {
return cl.newTorrentOpt(AddTorrentOpts{
InfoHash: ih,
Storage: specStorage,
})
}
// Return a Torrent ready for insertion into a Client.
func (cl *Client) newTorrentOpt(opts AddTorrentOpts) (t *Torrent) {
// use provided storage, if provided
storageClient := cl.defaultStorage
if opts.Storage != nil {
storageClient = storage.NewClient(opts.Storage)
}
t = &Torrent{
cl: cl,
infoHash: opts.InfoHash,
peers: prioritizedPeers{
om: btree.New(32),
getPrio: func(p PeerInfo) peerPriority {
ipPort := p.addr()
return bep40PriorityIgnoreError(cl.publicAddr(ipPort.IP), ipPort)
},
},
conns: make(map[*PeerConn]struct{}, 2*cl.config.EstablishedConnsPerTorrent),
halfOpen: make(map[string]PeerInfo),
pieceStateChanges: pubsub.NewPubSub(),
storageOpener: storageClient,
maxEstablishedConns: cl.config.EstablishedConnsPerTorrent,
metadataChanged: sync.Cond{
L: cl.locker(),
},
webSeeds: make(map[string]*Peer),
gotMetainfoC: make(chan struct{}),
}
t.networkingEnabled.Set()
t.logger = cl.logger.WithContextValue(t).WithNames("torrent", t.infoHash.HexString())
if opts.ChunkSize == 0 {
opts.ChunkSize = defaultChunkSize
}
t.setChunkSize(opts.ChunkSize)
return
}
// A file-like handle to some torrent data resource.
type Handle interface {
io.Reader
io.Seeker
io.Closer
io.ReaderAt
}
func (cl *Client) AddTorrentInfoHash(infoHash metainfo.Hash) (t *Torrent, new bool) {
return cl.AddTorrentInfoHashWithStorage(infoHash, nil)
}
// Adds a torrent by InfoHash with a custom Storage implementation.
// If the torrent already exists then this Storage is ignored and the
// existing torrent returned with `new` set to `false`
func (cl *Client) AddTorrentInfoHashWithStorage(infoHash metainfo.Hash, specStorage storage.ClientImpl) (t *Torrent, new bool) {
cl.lock()
defer cl.unlock()
t, ok := cl.torrents[infoHash]
if ok {
return
}
new = true
t = cl.newTorrent(infoHash, specStorage)
cl.eachDhtServer(func(s DhtServer) {
if cl.config.PeriodicallyAnnounceTorrentsToDht {
go t.dhtAnnouncer(s)
}
})
cl.torrents[infoHash] = t
cl.clearAcceptLimits()
t.updateWantPeersEvent()
// Tickle Client.waitAccept, new torrent may want conns.
cl.event.Broadcast()
return
}
// Adds a torrent by InfoHash with a custom Storage implementation.
// If the torrent already exists then this Storage is ignored and the
// existing torrent returned with `new` set to `false`
func (cl *Client) AddTorrentOpt(opts AddTorrentOpts) (t *Torrent, new bool) {
infoHash := opts.InfoHash
cl.lock()
defer cl.unlock()
t, ok := cl.torrents[infoHash]
if ok {
return
}
new = true
t = cl.newTorrentOpt(opts)
cl.eachDhtServer(func(s DhtServer) {
if cl.config.PeriodicallyAnnounceTorrentsToDht {
go t.dhtAnnouncer(s)
}
})
cl.torrents[infoHash] = t
cl.clearAcceptLimits()
t.updateWantPeersEvent()
// Tickle Client.waitAccept, new torrent may want conns.
cl.event.Broadcast()
return
}
type AddTorrentOpts struct {
InfoHash InfoHash
Storage storage.ClientImpl
ChunkSize pp.Integer
}
// Add or merge a torrent spec. Returns new if the torrent wasn't already in the client. See also
// Torrent.MergeSpec.
func (cl *Client) AddTorrentSpec(spec *TorrentSpec) (t *Torrent, new bool, err error) {
t, new = cl.AddTorrentOpt(AddTorrentOpts{
InfoHash: spec.InfoHash,
Storage: spec.Storage,
ChunkSize: spec.ChunkSize,
})
modSpec := *spec
if new {
// ChunkSize was already applied by adding a new Torrent, and MergeSpec disallows changing
// it.
modSpec.ChunkSize = 0
}
err = t.MergeSpec(&modSpec)
if err != nil && new {
t.Drop()
}
return
}
type stringAddr string
var _ net.Addr = stringAddr("")
func (stringAddr) Network() string { return "" }
func (me stringAddr) String() string { return string(me) }
// The trackers will be merged with the existing ones. If the Info isn't yet known, it will be set.
// spec.DisallowDataDownload/Upload will be read and applied
// The display name is replaced if the new spec provides one. Note that any `Storage` is ignored.
func (t *Torrent) MergeSpec(spec *TorrentSpec) error {
if spec.DisplayName != "" {
t.SetDisplayName(spec.DisplayName)
}
t.initialPieceCheckDisabled = spec.DisableInitialPieceCheck
if spec.InfoBytes != nil {
err := t.SetInfoBytes(spec.InfoBytes)
if err != nil {
return err
}
}
cl := t.cl
cl.AddDhtNodes(spec.DhtNodes)
cl.lock()
defer cl.unlock()
useTorrentSources(spec.Sources, t)
for _, url := range spec.Webseeds {
t.addWebSeed(url)
}
for _, peerAddr := range spec.PeerAddrs {
t.addPeer(PeerInfo{
Addr: stringAddr(peerAddr),
Source: PeerSourceDirect,
Trusted: true,
})
}
if spec.ChunkSize != 0 {
panic("chunk size cannot be changed for existing Torrent")
}
t.addTrackers(spec.Trackers)
t.maybeNewConns()
t.dataDownloadDisallowed.SetBool(spec.DisallowDataDownload)
t.dataUploadDisallowed = spec.DisallowDataUpload
return nil
}
func useTorrentSources(sources []string, t *Torrent) {
// TODO: bind context to the lifetime of *Torrent so that it's cancelled if the torrent closes
ctx := context.Background()
for i := 0; i < len(sources); i += 1 {
s := sources[i]
go func() {
if err := useTorrentSource(ctx, s, t); err != nil {
t.logger.WithDefaultLevel(log.Warning).Printf("using torrent source %q: %v", s, err)
} else {
t.logger.Printf("successfully used source %q", s)
}
}()
}
}
func useTorrentSource(ctx context.Context, source string, t *Torrent) (err error) {
ctx, cancel := context.WithCancel(ctx)
defer cancel()
go func() {
select {
case <-t.GotInfo():
case <-t.Closed():
case <-ctx.Done():
}
cancel()
}()
var req *http.Request
if req, err = http.NewRequestWithContext(ctx, http.MethodGet, source, nil); err != nil {
panic(err)
}
var resp *http.Response
if resp, err = http.DefaultClient.Do(req); err != nil {
return
}
var mi metainfo.MetaInfo
err = bencode.NewDecoder(resp.Body).Decode(&mi)
resp.Body.Close()
if err != nil {
if ctx.Err() != nil {
return nil
}
return
}
return t.MergeSpec(TorrentSpecFromMetaInfo(&mi))
}
func (cl *Client) dropTorrent(infoHash metainfo.Hash, wg *sync.WaitGroup) (err error) {
t, ok := cl.torrents[infoHash]
if !ok {
err = fmt.Errorf("no such torrent")
return
}
err = t.close(wg)
if err != nil {
panic(err)
}
delete(cl.torrents, infoHash)
return
}
func (cl *Client) allTorrentsCompleted() bool {
for _, t := range cl.torrents {
if !t.haveInfo() {
return false
}
if !t.haveAllPieces() {
return false
}
}
return true
}
// Returns true when all torrents are completely downloaded and false if the
// client is stopped before that.
func (cl *Client) WaitAll() bool {
cl.lock()
defer cl.unlock()
for !cl.allTorrentsCompleted() {
if cl.closed.IsSet() {
return false
}
cl.event.Wait()
}
return true
}
// Returns handles to all the torrents loaded in the Client.
func (cl *Client) Torrents() []*Torrent {
cl.lock()
defer cl.unlock()
return cl.torrentsAsSlice()
}
func (cl *Client) torrentsAsSlice() (ret []*Torrent) {
for _, t := range cl.torrents {
ret = append(ret, t)
}
return
}
func (cl *Client) AddMagnet(uri string) (T *Torrent, err error) {
spec, err := TorrentSpecFromMagnetUri(uri)
if err != nil {
return
}
T, _, err = cl.AddTorrentSpec(spec)
return
}
func (cl *Client) AddTorrent(mi *metainfo.MetaInfo) (T *Torrent, err error) {
ts, err := TorrentSpecFromMetaInfoErr(mi)
if err != nil {
return
}
T, _, err = cl.AddTorrentSpec(ts)
return
}
func (cl *Client) AddTorrentFromFile(filename string) (T *Torrent, err error) {
mi, err := metainfo.LoadFromFile(filename)
if err != nil {
return
}
return cl.AddTorrent(mi)
}
func (cl *Client) DhtServers() []DhtServer {
return cl.dhtServers
}
func (cl *Client) AddDhtNodes(nodes []string) {
for _, n := range nodes {
hmp := missinggo.SplitHostMaybePort(n)
ip := net.ParseIP(hmp.Host)
if ip == nil {
cl.logger.Printf("won't add DHT node with bad IP: %q", hmp.Host)
continue
}
ni := krpc.NodeInfo{
Addr: krpc.NodeAddr{
IP: ip,
Port: hmp.Port,
},
}
cl.eachDhtServer(func(s DhtServer) {
s.AddNode(ni)
})
}
}
func (cl *Client) banPeerIP(ip net.IP) {
cl.logger.Printf("banning ip %v", ip)
if cl.badPeerIPs == nil {
cl.badPeerIPs = make(map[string]struct{})
}
cl.badPeerIPs[ip.String()] = struct{}{}
}
func (cl *Client) newConnection(nc net.Conn, outgoing bool, remoteAddr PeerRemoteAddr, network, connString string) (c *PeerConn) {
if network == "" {
panic(remoteAddr)
}
c = &PeerConn{
Peer: Peer{
outgoing: outgoing,
choking: true,
peerChoking: true,
PeerMaxRequests: 250,
RemoteAddr: remoteAddr,
Network: network,
callbacks: &cl.config.Callbacks,
},
connString: connString,
conn: nc,
}
c.peerImpl = c
c.logger = cl.logger.WithDefaultLevel(log.Warning).WithContextValue(c)
c.setRW(connStatsReadWriter{nc, c})
c.r = &rateLimitedReader{
l: cl.config.DownloadRateLimiter,
r: c.r,
}
c.logger.WithDefaultLevel(log.Debug).Printf("initialized with remote %v over network %v (outgoing=%t)", remoteAddr, network, outgoing)
for _, f := range cl.config.Callbacks.NewPeer {
f(&c.Peer)
}
return
}
func (cl *Client) onDHTAnnouncePeer(ih metainfo.Hash, ip net.IP, port int, portOk bool) {
cl.lock()
defer cl.unlock()
t := cl.torrent(ih)
if t == nil {
return
}
t.addPeers([]PeerInfo{{
Addr: ipPortAddr{ip, port},
Source: PeerSourceDhtAnnouncePeer,
}})
}
func firstNotNil(ips ...net.IP) net.IP {
for _, ip := range ips {
if ip != nil {
return ip
}
}
return nil
}
func (cl *Client) eachListener(f func(Listener) bool) {
for _, s := range cl.listeners {
if !f(s) {
break
}
}
}
func (cl *Client) findListener(f func(Listener) bool) (ret Listener) {
for i := 0; i < len(cl.listeners); i += 1 {
if ret = cl.listeners[i]; f(ret) {
return
}
}
return nil
}
func (cl *Client) publicIp(peer net.IP) net.IP {
// TODO: Use BEP 10 to determine how peers are seeing us.
if peer.To4() != nil {
return firstNotNil(
cl.config.PublicIp4,
cl.findListenerIp(func(ip net.IP) bool { return ip.To4() != nil }),
)
}
return firstNotNil(
cl.config.PublicIp6,
cl.findListenerIp(func(ip net.IP) bool { return ip.To4() == nil }),
)
}
func (cl *Client) findListenerIp(f func(net.IP) bool) net.IP {
l := cl.findListener(
func(l Listener) bool {
return f(addrIpOrNil(l.Addr()))
},
)
if l == nil {
return nil
}
return addrIpOrNil(l.Addr())
}
// Our IP as a peer should see it.
func (cl *Client) publicAddr(peer net.IP) IpPort {
return IpPort{IP: cl.publicIp(peer), Port: uint16(cl.incomingPeerPort())}
}
// ListenAddrs addresses currently being listened to.
func (cl *Client) ListenAddrs() (ret []net.Addr) {
cl.lock()
ret = make([]net.Addr, len(cl.listeners))
for i := 0; i < len(cl.listeners); i += 1 {
ret[i] = cl.listeners[i].Addr()
}
cl.unlock()
return
}
func (cl *Client) onBadAccept(addr PeerRemoteAddr) {
ipa, ok := tryIpPortFromNetAddr(addr)
if !ok {
return
}
ip := maskIpForAcceptLimiting(ipa.IP)
if cl.acceptLimiter == nil {
cl.acceptLimiter = make(map[ipStr]int)
}
cl.acceptLimiter[ipStr(ip.String())]++
}
func maskIpForAcceptLimiting(ip net.IP) net.IP {
if ip4 := ip.To4(); ip4 != nil {
return ip4.Mask(net.CIDRMask(24, 32))
}
return ip
}
func (cl *Client) clearAcceptLimits() {
cl.acceptLimiter = nil
}
func (cl *Client) acceptLimitClearer() {
for {
select {
case <-cl.closed.Done():
return
case <-time.After(15 * time.Minute):
cl.lock()
cl.clearAcceptLimits()
cl.unlock()
}
}
}
func (cl *Client) rateLimitAccept(ip net.IP) bool {
if cl.config.DisableAcceptRateLimiting {
return false
}
return cl.acceptLimiter[ipStr(maskIpForAcceptLimiting(ip).String())] > 0
}
func (cl *Client) rLock() {
cl._mu.RLock()
}
func (cl *Client) rUnlock() {
cl._mu.RUnlock()
}
func (cl *Client) lock() {
cl._mu.Lock()
}
func (cl *Client) unlock() {
cl._mu.Unlock()
}
func (cl *Client) locker() *lockWithDeferreds {
return &cl._mu
}
func (cl *Client) String() string {
return fmt.Sprintf("<%[1]T %[1]p>", cl)
}
// Returns connection-level aggregate stats at the Client level. See the comment on
// TorrentStats.ConnStats.
func (cl *Client) ConnStats() ConnStats {
return cl.stats.Copy()
}