feat: support udp associate

2025-12-16 16:57:08 +00:00 · 2024-03-05 00:27:13 +08:00 · 2024-03-05 00:27:13 +08:00 · b624435a6c
commit b624435a6c
parent 41ff05c4b6
5 changed files with 143 additions and 50 deletions
--- a/README.md
+++ b/README.md
@ -109,6 +109,6 @@ rules:
 - [x] 支持 LuCI
 - [x] 优化部署流程
 - [ ] 支持 SOCK5 Auth
- [ ] 支持 UDP
+- [x] 支持 UDP
 - [ ] 支持 IPv6
 - [ ] 性能提升
--- a/build.sh
+++ b/build.sh
@ -1,7 +1,7 @@
 #!/bin/sh

 project_name="ua3f"
-release_version="0.2.3"
+release_version="0.3.0"
 target=cmd/ua3f.go

 release_dir=./bin
--- a/cmd/ua3f.go
+++ b/cmd/ua3f.go
@ -17,7 +17,7 @@ import (
 	"github.com/sirupsen/logrus"
 )

-var version = "0.2.3"
+var version = "0.3.0"
 var payloadByte []byte
 var cache *expirable.LRU[string, string]
 var HTTP_METHOD = []string{"GET", "POST", "HEAD", "PUT", "DELETE", "OPTIONS", "TRACE", "CONNECT"}
@ -91,6 +91,12 @@ func process(client net.Conn) {
 	}
 	target, destAddrPort, err := Socks5Connect(client)
 	if err != nil {
+		// UDP
+		if strings.Contains(err.Error(), "UDP Associate") {
+			Socks5UDP(client)
+			client.Close()
+			return
+		}
 		logrus.Error("Connect failed: ", err)
 		client.Close()
 		return
@ -128,48 +134,134 @@ func Socks5Auth(client net.Conn) (err error) {
 	return nil
 }

-// func Socks5UDP() {
-//	https://datatracker.ietf.org/doc/html/rfc1928
-// 	// _, _ = client.Write([]byte{0x05, 0x00, 0x00, 0x01, 0x7f, 0, 0, 0x1, 0x04, 0x38})
-// 	_, _ = client.Write([]byte{0x05, 0x00, 0x00, 0x01, 0, 0, 0, 0, 0x04, 0x38})
-// 	server, _ := net.ListenUDP("udp", &net.UDPAddr{IP: net.IPv4zero, Port: 1080})
-// 	_, _ = server.Read(buf[:4])
-// 	frag, atyp := buf[2], buf[3]
-// 	addr := ""
-// 	switch atyp {
-//	case 1:
-//		n, err = server.Read(buf[:4])
-//		if n != 4 {
-//			return nil, "", errors.New("invalid IPv4:" + err.Error())
-//		}
-//		addr = fmt.Sprintf("%d.%d.%d.%d", buf[0], buf[1], buf[2], buf[3])
-//	case 3:
-//		n, err = server.Read(buf[:1])
-//		if n != 1 {
-//			return nil, "", errors.New("invalid hostname:" + err.Error())
-//		}
-//		addrLen := int(buf[0])
-//		n, err = server.Read(buf[:addrLen])
-//		if n != addrLen {
-//			return nil, "", errors.New("invalid hostname:" + err.Error())
-//		}
-//		addr = string(buf[:addrLen])
-//	case 4:
-//		return nil, "", errors.New("IPv6: no supported yet")
-//	default:
-//		return nil, "", errors.New("invalid atyp")
-// 	}
-// 	n, err = server.Read(buf[:2])
-// 	port := binary.BigEndian.Uint16(buf[:2])
-// 	destAddrPort := fmt.Sprintf("%s:%d", addr, port)
-// 	logrus.Debug(fmt.Sprintf("Connecting %s", destAddrPort))
-// 	dest, err := net.Dial("udp", destAddrPort)
-// 	if err != nil {
-//		return nil, destAddrPort, errors.New("dial dst:" + err.Error())
-// 	}
-// 	logrus.Debug(fmt.Sprintf("Connected %s", destAddrPort))
-//
-// }
+func isAlive(conn net.Conn) bool {
+	one := make([]byte, 1)
+	conn.SetReadDeadline(time.Now().Add(time.Second * 5))
+	_, err := conn.Read(one)
+	if err != nil {
+		if err == io.EOF {
+			logrus.Debug(fmt.Sprintf("[%s] isAlive: EOF", conn.RemoteAddr().String()))
+			return false
+		} else if strings.Contains(err.Error(), "use of closed network connection") {
+			logrus.Debug(fmt.Sprintf("[%s] isAlive: closed", conn.RemoteAddr().String()))
+			return false
+		} else if strings.Contains(err.Error(), "i/o timeout") {
+			logrus.Debug(fmt.Sprintf("[%s] isAlive: timeout", conn.RemoteAddr().String()))
+			return true
+		} else {
+			logrus.Debug(fmt.Sprintf("[%s] isAlive: %s", conn.RemoteAddr().String(), err.Error()))
+			return false
+		}
+	}
+	conn.SetReadDeadline(time.Time{})
+	return true
+}
+
+func Socks5UDP(client net.Conn) {
+	udpserver, err := net.ListenUDP("udp4", &net.UDPAddr{IP: net.IPv4zero, Port: 0})
+	if err != nil {
+		logrus.Error(fmt.Sprintf("[%s][UDP] ListenUDP failed: %s", client.RemoteAddr().String(), err.Error()))
+		return
+	}
+	_, port, _ := net.SplitHostPort(udpserver.LocalAddr().String())
+	logrus.Debug(fmt.Sprintf("[%s][UDP] ListenUDP on %s", client.RemoteAddr().String(), port))
+	portInt, _ := net.LookupPort("udp", port)
+	portBytes := make([]byte, 2)
+	binary.BigEndian.PutUint16(portBytes, uint16(portInt))
+	_, err = client.Write([]byte{0x05, 0x00, 0x00, 0x01, 0, 0, 0, 0, portBytes[0], portBytes[1]})
+	if err != nil {
+		logrus.Error(fmt.Sprintf("[%s][UDP] Write rsp failed: %s", client.RemoteAddr().String(), err.Error()))
+		return
+	}
+	buf := make([]byte, 65535)
+	udpPortMap := make(map[string][]byte)
+	var clientAddr *net.UDPAddr
+	var isDomain bool = false
+	for {
+		udpserver.SetReadDeadline(time.Now().Add(time.Second * 10))
+		n, fromAddr, err := udpserver.ReadFromUDP(buf)
+		if err != nil {
+			if strings.Contains(err.Error(), "i/o timeout") {
+				logrus.Debug(fmt.Sprintf("[%s][UDP] ReadFromUDP failed: %s", client.RemoteAddr().String(), err.Error()))
+				if !isAlive(client) {
+					logrus.Debug(fmt.Sprintf("[%s][UDP] client is not alive", client.RemoteAddr().String()))
+					udpserver.Close()
+					return
+				}
+			} else {
+				logrus.Error(fmt.Sprintf("[%s][UDP] ReadFromUDP failed: %s", client.RemoteAddr().String(), err.Error()))
+			}
+
+			continue
+		}
+		if clientAddr == nil {
+			clientAddr = fromAddr
+		}
+
+		if clientAddr.IP.Equal(fromAddr.IP) && clientAddr.Port == fromAddr.Port {
+			// from client
+			atyp := buf[3]
+			targetAddr := ""
+			var targetPort uint16 = 0
+			var payload []byte
+			var header []byte
+			var targetIP net.IP
+			if atyp == 1 {
+				isDomain = false
+				targetAddr = fmt.Sprintf("%d.%d.%d.%d", buf[4], buf[5], buf[6], buf[7])
+				targetIP = net.ParseIP(targetAddr)
+				targetPort = binary.BigEndian.Uint16(buf[8:10])
+				payload = buf[10:n]
+				header = buf[0:10]
+			} else if atyp == 3 {
+				isDomain = true
+				addrLen := int(buf[4])
+				targetAddr = string(buf[5 : 5+addrLen])
+				targetIPaddr, err := net.ResolveIPAddr("ip", targetAddr)
+				if err != nil {
+					logrus.Error(fmt.Sprintf("[%s][UDP] ResolveIPAddr failed: %s", client.RemoteAddr().String(), err.Error()))
+					continue
+				}
+				targetIP = targetIPaddr.IP
+				targetPort = binary.BigEndian.Uint16(buf[5+addrLen : 5+addrLen+2])
+				payload = buf[5+addrLen+2 : n]
+				header = buf[0 : 5+addrLen+2]
+			} else if atyp == 4 {
+				logrus.Error(fmt.Sprintf("[%s][UDP] IPv6: no supported yet", client.RemoteAddr().String()))
+				continue
+			} else {
+				logrus.Error(fmt.Sprintf("[%s][UDP] invalid atyp", client.RemoteAddr().String()))
+				continue
+			}
+			// targetAddrPort := fmt.Sprintf("%s:%d", targetAddr, targetPort)
+			remoteAddr := &net.UDPAddr{IP: targetIP, Port: int(targetPort)}
+			udpPortMap[remoteAddr.String()] = make([]byte, len(header))
+			copy(udpPortMap[remoteAddr.String()], header)
+			udpserver.SetWriteDeadline(time.Now().Add(time.Second * 10))
+			if _, err = udpserver.WriteToUDP(payload, remoteAddr); err != nil {
+				logrus.Error(fmt.Sprintf("[%s][UDP] WriteToUDP failed: %s", client.RemoteAddr().String(), err.Error()))
+				continue
+			}
+		} else {
+			// from remote
+			fmt.Print(fromAddr.String())
+			header := udpPortMap[fromAddr.String()]
+			if header == nil {
+				logrus.Error(fmt.Sprintf("[%s][UDP] udpPortMap invalid header", client.RemoteAddr().String()))
+				continue
+			}
+			// header + body
+			if isDomain {
+				header = header[0:4]
+			}
+			body := append(header, buf[:n]...)
+			if _, err = udpserver.WriteToUDP(body, clientAddr); err != nil {
+				logrus.Error(fmt.Sprintf("[%s][UDP] WriteToUDP failed: %s", client.RemoteAddr().String(), err.Error()))
+				continue
+			}
+		}
+	}
+}

 func Socks5Connect(client net.Conn) (net.Conn, string, error) {
 	buf := make([]byte, 256)
@ -182,7 +274,7 @@ func Socks5Connect(client net.Conn) (net.Conn, string, error) {
 		return nil, "", errors.New("invalid ver")
 	}
 	if cmd == 3 {
-		return nil, "", errors.New("not support UDP")
+		return nil, "", errors.New("UDP Associate")
 	}
 	if cmd != 1 {
 		return nil, "", errors.New("invalid cmd, only support connect")
--- a/install.sh
+++ b/install.sh
@ -20,7 +20,7 @@ ckcmd() {
 cd /root
 getcpucore

-version=0.2.3
+version=0.3.0
 ua3f_tar=ua3f-$version-$cpucore.tar.gz

 if id -u shellclash >/dev/null 2>&1; then
@ -91,11 +91,12 @@ fi
 mkdir -p /usr/lib/lua/luci/controller
 mv controller.lua /usr/lib/lua/luci/controller/ua3f.lua

-rm /tmp/luci-modulecache/* >/dev/null 2>&1
-rm /tmp/luci-indexcache* >/dev/null 2>&1
+chmod +x /etc/config/ua3f >/dev/null 2>&1

 if [ $? -eq 0 ]; then
    echo "Install UA3F Success."
 fi

+rm /tmp/luci-modulecache/* >/dev/null 2>&1
+rm /tmp/luci-indexcache* >/dev/null 2>&1
 service ua3f.service reload >/dev/null 2>&1
--- a/luci/cbi.lua
+++ b/luci/cbi.lua
@ -3,7 +3,7 @@ local uci = require("luci.model.uci").cursor()
 ua3f = Map("ua3f",
    "UA3F",
    [[
-        <a href="https://github.com/SunBK201/UA3F" target="_blank">Version: 0.2.3</a>
+        <a href="https://github.com/SunBK201/UA3F" target="_blank">Version: 0.3.0</a>
        <br>
        Across the Campus we can reach every corner in the world.
    ]]