func tcpClient(addr string, key, message []byte) ([]byte, error) {
tcpaddr, err := net.ResolveTCPAddr("tcp", addr)
if err != nil {
return nil, err
}
ciphertext, err := libsodium.EncryptData(key, message)
if err != nil {
return nil, err
}
tcpconn, err := net.DialTCP("tcp", nil, tcpaddr)
if err != nil {
return nil, err
}
defer tcpconn.Close()
tcpconn.SetWriteDeadline(time.Now().Add(time.Duration(20) * time.Second))
_, err = tcpconn.Write(netstring.Marshall(ciphertext))
if err != nil {
return nil, err
}
tcpconn.SetReadDeadline(time.Now().Add(time.Duration(20) * time.Second))
bufReader := bufio.NewReader(tcpconn)
var buf bytes.Buffer
var ip []byte
for {
rData, err := bufReader.ReadBytes(',')
if err != nil {
if err == io.EOF {
return nil, err
}
buf.Write(rData)
continue
}
buf.Write(rData)
ip, err = netstring.Unmarshall(buf.Bytes())
if err != nil {
if err == netstring.ErrNsLenNotEqaulOrgLen {
continue
}
return nil, err
}
break
}
return ip, nil
}
func handleTCPConn(tcpconn *net.TCPConn, encryptKey []byte, buffer *bytes.Buffer, bpool *bpool.SizedBufferPool) {
defer tcpconn.Close()
defer bpool.Put(buffer)
var receiveData []byte
//tcpconn need read all data in 20 second ,otherwise Timeout() will be true
tcpconn.SetReadDeadline(time.Now().Add(time.Duration(20) * time.Second))
bufReader := bufio.NewReader(tcpconn)
for {
rData, err := bufReader.ReadBytes(',')
if err != nil {
if err == io.EOF {
log.Printf("TCPConn Read error\n")
return
}
buffer.Write(rData)
continue
}
buffer.Write(rData)
receiveData, err = netstring.Unmarshall(buffer.Bytes())
if err != nil {
if err == netstring.ErrNsLenNotEqaulOrgLen {
continue
} else {
log.Printf("netstring unmarshall error : %v\n", err)
return
}
}
break
}
_, err := libsodium.DecryptData(encryptKey, receiveData)
if err != nil {
log.Printf("tcp DecryptData error : %v\n", err)
return
}
tcpconn.SetWriteDeadline(time.Now().Add(time.Duration(20) * time.Second))
_, err = tcpconn.Write(netstring.Marshall([]byte(homeip)))
if err != nil {
log.Printf("tcpconn error : %v\n", err)
}
}
func handleUDPConn(udpconn *net.UDPConn, key []byte, receiveData []byte) {
//udpconn.SetReadDeadline(time.Now().Add(time.Duration(20) * time.Second))
receiveDatalen, addr, err := udpconn.ReadFrom(receiveData)
if err != nil {
log.Printf("udpconn ReadFrom err : %v\n", err)
}
receiveData, err = netstring.Unmarshall(receiveData[:receiveDatalen])
if err != nil {
log.Printf("netstring unmarshall error : %v\n", err)
return
}
_, err = libsodium.DecryptData(key, receiveData)
if err != nil {
log.Printf("udp DecryptData error : %v\n", err)
return
}
homeip = addr.String()
}