package socks import ( "v2ray.com/core/common/buf" "v2ray.com/core/common/log" v2net "v2ray.com/core/common/net" "v2ray.com/core/proxy" "v2ray.com/core/proxy/socks/protocol" "v2ray.com/core/transport/internet/udp" ) func (v *Server) listenUDP() error { v.udpServer = udp.NewServer(v.packetDispatcher) udpHub, err := udp.ListenUDP(v.meta.Address, v.meta.Port, udp.ListenOption{Callback: v.handleUDPPayload}) if err != nil { log.Error("Socks: Failed to listen on udp (", v.meta.Address, ":", v.meta.Port, "): ", err) return err } v.udpMutex.Lock() v.udpAddress = v2net.UDPDestination(v.config.GetNetAddress(), v.meta.Port) v.udpHub = udpHub v.udpMutex.Unlock() return nil } func (v *Server) handleUDPPayload(payload *buf.Buffer, session *proxy.SessionInfo) { source := session.Source log.Info("Socks: Client UDP connection from ", source) request, err := protocol.ReadUDPRequest(payload.Bytes()) payload.Release() if err != nil { log.Error("Socks: Failed to parse UDP request: ", err) return } if request.Data.Len() == 0 { request.Data.Release() return } if request.Fragment != 0 { log.Warning("Socks: Dropping fragmented UDP packets.") // TODO handle fragments request.Data.Release() return } log.Info("Socks: Send packet to ", request.Destination(), " with ", request.Data.Len(), " bytes") log.Access(source, request.Destination, log.AccessAccepted, "") v.udpServer.Dispatch(&proxy.SessionInfo{Source: source, Destination: request.Destination(), Inbound: v.meta}, request.Data, func(destination v2net.Destination, payload *buf.Buffer) { response := &protocol.Socks5UDPRequest{ Fragment: 0, Address: request.Destination().Address, Port: request.Destination().Port, Data: payload, } log.Info("Socks: Writing back UDP response with ", payload.Len(), " bytes to ", destination) udpMessage := buf.NewLocal(2048) response.Write(udpMessage) v.udpMutex.RLock() if !v.accepting { v.udpMutex.RUnlock() return } nBytes, err := v.udpHub.WriteTo(udpMessage.Bytes(), destination) v.udpMutex.RUnlock() udpMessage.Release() response.Data.Release() if err != nil { log.Error("Socks: failed to write UDP message (", nBytes, " bytes) to ", destination, ": ", err) } }) }