// Reads datagrams from the connection and queues them for processing on the
// l-goroutine.
func (dht *DHT) readLoop() {
for {
b, addr, err := denet.ReadDatagramFromUDP(dht.conn)
switch {
// Successful receive.
case err == nil:
dht.rxChan <- packet{
Data: b,
Addr: *addr,
}
// An address was unreachable.
case denet.ErrorIsPortUnreachable(err):
dht.addrUnreachableChan <- *addr
// Unless we are stopping, other errors should not occur.
case atomic.LoadUint32(&dht.stopping) == 0:
log.Errore(err, "unexpected error while receiving")
// We are stopping.
default:
return
}
}
}
// Read a message from the connection.
func Read(conn denet.UDPConn) (msg *Message, remoteAddr *net.UDPAddr, err error) {
buf, remoteAddr, err := denet.ReadDatagramFromUDP(conn)
if err != nil {
return
}
msg, err = Decode(buf)
return
}
func (c *client) recvLoop() {
for {
buf, _, err := net.ReadDatagramFromUDP(c.conn)
if err != nil {
return
}
rbio := bufio.NewReader(bytes.NewReader(buf))
res, err := http.ReadResponse(rbio, nil)
if err == nil {
c.handleResponse(res)
}
}
}
func makeRequest(dst gnet.IP, opcode opcodeNo, data []byte) ([]byte, error) {
conn, err := gnet.DialUDP("udp", nil, &gnet.UDPAddr{dst, hostToGatewayPort, ""})
if err != nil {
return nil, err
}
defer conn.Close()
msg := make([]byte, 2)
msg[0] = version0 // Version 0
msg[1] = byte(opcode) // Opcode
msg = append(msg, data...)
rconf := backoff
rconf.Reset()
for {
// here we use the 'delay' as the timeout
maxtime := rconf.NextDelay()
if maxtime == 0 {
// max tries reached
break
}
err = conn.SetDeadline(time.Now().Add(maxtime))
if err != nil {
return nil, err
}
_, err = conn.Write(msg)
if err != nil {
return nil, err
}
var res []byte
var uaddr *gnet.UDPAddr
res, uaddr, err = net.ReadDatagramFromUDP(conn)
if err != nil {
if err.(gnet.Error).Timeout() {
// try again
continue
}
return nil, err
}
if !uaddr.IP.Equal(dst) || uaddr.Port != hostToGatewayPort {
continue
}
if len(res) < 4 {
continue
}
if res[0] != 0 || res[1] != (0x80|byte(opcode)) {
continue
}
rc := binary.BigEndian.Uint16(res[2:])
if rc != 0 {
return nil, fmt.Errorf("NAT-PMP: default gateway responded with nonzero error code %d", rc)
}
return res[4:], nil
}
return nil, natpmpErrTimeout
}
