Esempio n. 1
0
func (s *Server) handleQuery(source Addr, m krpc.Msg) {
	node := s.getNode(source, m.SenderID())
	node.lastGotQuery = time.Now()
	if s.config.OnQuery != nil {
		propagate := s.config.OnQuery(&m, source.UDPAddr())
		if !propagate {
			return
		}
	}
	// Don't respond.
	if s.config.Passive {
		return
	}
	args := m.A
	switch m.Q {
	case "ping":
		s.reply(source, m.T, krpc.Return{})
	case "get_peers": // TODO: Extract common behaviour with find_node.
		targetID := args.InfoHash
		if len(targetID) != 20 {
			break
		}
		var rNodes []krpc.NodeInfo
		// TODO: Reply with "values" list if we have peers instead.
		for _, node := range s.closestGoodNodes(8, targetID) {
			rNodes = append(rNodes, node.NodeInfo())
		}
		s.reply(source, m.T, krpc.Return{
			Nodes: rNodes,
			// TODO: Generate this dynamically, and store it for the source.
			Token: "hi",
		})
	case "find_node": // TODO: Extract common behaviour with get_peers.
		targetID := args.Target
		if len(targetID) != 20 {
			log.Printf("bad DHT query: %v", m)
			return
		}
		var rNodes []krpc.NodeInfo
		if node := s.nodeByID(targetID); node != nil {
			rNodes = append(rNodes, node.NodeInfo())
		} else {
			// This will probably cause a crash for IPv6, but meh.
			for _, node := range s.closestGoodNodes(8, targetID) {
				rNodes = append(rNodes, node.NodeInfo())
			}
		}
		s.reply(source, m.T, krpc.Return{
			Nodes: rNodes,
		})
	case "announce_peer":
		// TODO(anacrolix): Implement this lolz.
		// log.Print(m)
	case "vote":
		// TODO(anacrolix): Or reject, I don't think I want this.
	default:
		log.Printf("%s: not handling received query: q=%s", s, m.Q)
		return
	}
}
Esempio n. 2
0
func (s *Server) processPacket(b []byte, addr Addr) {
	if len(b) < 2 || b[0] != 'd' || b[len(b)-1] != 'e' {
		// KRPC messages are bencoded dicts.
		readNotKRPCDict.Add(1)
		return
	}
	var d krpc.Msg
	err := bencode.Unmarshal(b, &d)
	if err != nil {
		readUnmarshalError.Add(1)
		func() {
			if se, ok := err.(*bencode.SyntaxError); ok {
				// The message was truncated.
				if int(se.Offset) == len(b) {
					return
				}
				// Some messages seem to drop to nul chars abrubtly.
				if int(se.Offset) < len(b) && b[se.Offset] == 0 {
					return
				}
				// The message isn't bencode from the first.
				if se.Offset == 0 {
					return
				}
			}
			// if missinggo.CryHeard() {
			// 	log.Printf("%s: received bad krpc message from %s: %s: %+q", s, addr, err, b)
			// }
		}()
		return
	}
	s.mu.Lock()
	defer s.mu.Unlock()
	if s.closed.IsSet() {
		return
	}
	if d.Y == "q" {
		readQuery.Add(1)
		s.handleQuery(addr, d)
		return
	}
	t := s.findResponseTransaction(d.T, addr)
	if t == nil {
		//log.Printf("unexpected message: %#v", d)
		return
	}
	node := s.getNode(addr, d.SenderID())
	node.lastGotResponse = time.Now()
	// TODO: Update node ID as this is an authoritative packet.
	go t.handleResponse(d)
	s.deleteTransaction(t)
}