// Sets up the DHT node for peer bootstrapping
func (self *DHT) Init() error {
//sum := sha1.Sum([]byte(self.Config.Info))
// Create a hex encoded sha1 sum of a string to be used for DH
//infoHash, err := dht.DecodeInfoHash(hex.EncodeToString(sum[:]))
cfg := dht.NewConfig()
cfg.Port = self.Config.Port
cfg.NumTargetPeers = self.Config.DesiredPeers
d, err := dht.New(cfg)
if err != nil {
return err
}
//self.InfoHash = infoHash
self.DHT = d
//add the bootstrap nodes
for _, addr := range self.Config.BootstrapNodes {
self.DHT.AddNode(addr)
}
if self.Config.Disabled {
// We have to initialize the DHT anyway because daemon loop needs
// to read from its initialized chans. As long as Start() is prevented,
// the DHT will not run.
logger.Info("DHT is disabled")
} else {
logger.Info("Init DHT on port %d", self.Config.Port)
}
return nil
}
func DiscoverPeers(cm *network.ConnectionManager, address string) {
// Hex encoded string: "The Distributed Bay!"
ih, err := dht.DecodeInfoHash("5468652044697374726962757465642042617921")
if err != nil {
log.Fatalf("DHT DecodeInfoHash error: %v\n", err)
}
_, portStr, err := net.SplitHostPort(address)
if err != nil {
log.Fatal("Bind address error!", err)
}
port, err := strconv.Atoi(portStr)
if err != nil {
log.Fatal(err)
}
config := dht.NewConfig()
config.Port = port
config.NumTargetPeers = 10
node, err := dht.New(config)
if err != nil {
log.Fatal("Error creating DHT node!")
}
go node.Run()
go checkPeers(node, cm)
log.Println("Requesting peers from the DHT!")
for {
node.PeersRequest(string(ih), true)
time.Sleep(15 * time.Second)
}
}
func NewControlSession(shareid id.Id, listenPort int, session *sharesession.Session, trackers []string) (*ControlSession, error) {
sid := "-tt" + strconv.Itoa(os.Getpid()) + "_" + strconv.FormatInt(rand.Int63(), 10)
// TODO: UPnP UDP port mapping.
cfg := dht.NewConfig()
cfg.Port = listenPort
cfg.NumTargetPeers = TARGET_NUM_PEERS
dhtNode, err := dht.New(cfg)
if err != nil {
log.Fatal("DHT node creation error", err)
}
current := session.GetCurrentIHMessage()
var currentIhMessage IHMessage
err = bencode.NewDecoder(strings.NewReader(current)).Decode(¤tIhMessage)
if err != nil {
log.Printf("Couldn't decode current message, starting from scratch: %s\n", err)
}
rev := "0-"
if currentIhMessage.Info.Rev != "" {
parts := strings.Split(currentIhMessage.Info.Rev, "-")
if len(parts) == 2 {
if _, err := strconv.Atoi(parts[0]); err == nil {
rev = currentIhMessage.Info.Rev
}
}
}
cs := &ControlSession{
Port: listenPort,
PeerID: sid[:20],
ID: shareid,
Torrents: make(chan Announce),
NewPeers: make(chan string),
dht: dhtNode,
peerMessageChan: make(chan peerMessage),
quit: make(chan struct{}),
ourExtensions: map[int]string{
1: "ut_pex",
2: "bs_metadata",
},
peers: newPeers(),
currentIH: currentIhMessage.Info.InfoHash,
rev: rev,
trackers: trackers,
session: session,
}
go cs.dht.Run()
cs.dht.PeersRequest(string(cs.ID.Infohash), true)
go cs.Run()
return cs, nil
}
func startDHT(listenPort int) *dht.DHT {
// TODO: UPnP UDP port mapping.
cfg := dht.NewConfig()
cfg.Port = listenPort
cfg.NumTargetPeers = TARGET_NUM_PEERS
dhtnode, err := dht.New(cfg)
if err != nil {
log.Println("DHT node creation error:", err)
return nil
}
go dhtnode.Run()
return dhtnode
}
func NewTorrentSession(fileDir string, torrent string, listenPort uint16, seedRatio float64) (ts *TorrentSession, err error) {
t := &TorrentSession{
fileDir: fileDir,
seedRatio: seedRatio,
peers: make(map[string]*peerState),
peerMessageChan: make(chan peerMessage),
activePieces: make(map[int]*ActivePiece),
quit: make(chan bool),
torrentFile: torrent,
chokePolicy: &ClassicChokePolicy{},
chokePolicyHeartbeat: time.Tick(10 * time.Second),
}
fromMagnet := strings.HasPrefix(torrent, "magnet:")
t.M, err = GetMetaInfo(torrent)
if err != nil {
return
}
dhtAllowed := useDHT && t.M.Info.Private == 0
if dhtAllowed {
// TODO: UPnP UDP port mapping.
cfg := dht.NewConfig()
cfg.Port = int(listenPort)
cfg.NumTargetPeers = TARGET_NUM_PEERS
if t.dht, err = dht.New(cfg); err != nil {
log.Println("DHT node creation error", err)
return
}
go t.dht.Run()
}
t.si = &SessionInfo{
PeerId: peerId(),
Port: listenPort,
UseDHT: dhtAllowed,
FromMagnet: fromMagnet,
HaveTorrent: false,
ME: &MetaDataExchange{},
OurExtensions: map[int]string{1: "ut_metadata"},
}
t.setHeader()
if !t.si.FromMagnet {
t.load()
}
return t, err
}
func NewDhtNode(port, numTargetPeers int, c *PeerCache) (*DhtNode, error) {
conf := dht.NewConfig()
conf.Port = port
conf.NumTargetPeers = numTargetPeers
node, err := dht.New(conf)
if err != nil {
return nil, err
}
d := &DhtNode{node: node}
go d.node.Run()
go d.drainResults(c)
return d, nil
}
func NewTorrentSession(torrent string, listenPort int) (ts *TorrentSession, err error) {
t := &TorrentSession{
peers: make(map[string]*peerState),
peerMessageChan: make(chan peerMessage),
activePieces: make(map[int]*ActivePiece),
quit: make(chan bool),
}
if useDHT {
// TODO: UPnP UDP port mapping.
cfg := dht.NewConfig()
cfg.Port = listenPort
cfg.NumTargetPeers = TARGET_NUM_PEERS
if t.dht, err = dht.New(cfg); err != nil {
log.Println("DHT node creation error", err)
return
}
go t.dht.Run()
}
fromMagnet := strings.HasPrefix(torrent, "magnet:")
t.m, err = getMetaInfo(torrent)
if err != nil {
return
}
t.si = &SessionInfo{
PeerId: peerId(),
Port: listenPort,
UseDHT: useDHT,
FromMagnet: fromMagnet,
HaveTorrent: false,
ME: &MetaDataExchange{},
OurExtensions: map[int]string{1: "ut_metadat"},
}
if !t.si.FromMagnet {
t.load()
}
return t, err
}
func (d *DiscoveryDHT) Run() error {
var err error
d.ih, err = dht.DecodeInfoHash(d.localNode.Config().NetworkID)
if err != nil {
return fmt.Errorf("decode infohash err: %s", err)
}
config := dht.NewConfig()
config.Port = d.localNode.State().ListenPort
d.node, err = dht.New(config)
if err != nil {
return fmt.Errorf("new dht init err: %s", err)
}
if err = d.node.Start(); err != nil {
return fmt.Errorf("dht start err: %s", err)
}
d.waitGroup.Add(2)
go d.process()
go d.awaitPeers()
d.waitGroup.Wait()
return nil
}
func main() {
ipv6Address := flag.String("v6", "", "Address to bind to IPv6 interface")
flag.Parse()
// To see logs, use the -logtostderr flag and change the verbosity with
// -v 0 (less verbose) up to -v 5 (more verbose).
if len(flag.Args()) != 1 {
fmt.Fprintf(os.Stderr, "Usage: %v <infohash>\n\n", os.Args[0])
fmt.Fprintf(os.Stderr, "Example infohash: %v\n", exampleIH)
flag.PrintDefaults()
os.Exit(1)
}
ih, err := dht.DecodeInfoHash(flag.Args()[0])
if err != nil {
fmt.Fprintf(os.Stderr, "DecodeInfoHash error: %v\n", err)
os.Exit(1)
}
conf4 := dht.NewConfig()
conf4.UDPProto = "udp4"
conf4.Port = 8445
// standard IPv4 bootstrap nodes = dht.transmissionbt.com
// router.utorrent.com router.bittorrent.com
conf6 := dht.NewConfig()
conf6.UDPProto = "udp6"
conf6.Port = 8445
conf6.Address = *ipv6Address
// Starts a DHT node with the default options. It picks a random UDP port. To change this, see dht.NewConfig.
d4, err := dht.New(conf4)
if err != nil {
fmt.Fprintf(os.Stderr, "New DHT error: %v", err)
os.Exit(1)
}
var d6 *dht.DHT
if len(*ipv6Address) > 1 {
fmt.Printf("Tring to bind to IPv6=%s\n", *ipv6Address)
d6, err = dht.New(conf6)
if err != nil {
fmt.Fprintf(os.Stderr, "New DHT error: %v", err)
os.Exit(1)
}
if err = d6.Start(); err != nil {
fmt.Fprintf(os.Stderr, "DHT start error: %v", err)
os.Exit(1)
}
go drainresults(d6)
} else {
fmt.Fprintf(os.Stderr, "Not binding to IPv6 interface. If desired pass -v6=[address] for the\n")
fmt.Fprintf(os.Stderr, "address you want the DHT to bind to. Privacy addresses are not recommended\n")
fmt.Fprintf(os.Stderr, "Since they can expire and connections will fail\n\n")
}
// For debugging.
go http.ListenAndServe(fmt.Sprintf(":%d", httpPortTCP), nil)
if err = d4.Start(); err != nil {
fmt.Fprintf(os.Stderr, "DHT start error: %v", err)
os.Exit(1)
}
go drainresults(d4)
for {
d4.PeersRequest(string(ih), true)
if len(*ipv6Address) > 1 {
d6.PeersRequest(string(ih), true)
}
time.Sleep(5 * time.Second)
}
}
