Added custom type for Proxy Protocol Version

- Changed enum type for proxy protocol
- Added warning for proxy protocol 1 on UDP selection in UI

src/mod/streamproxy/handler.go

@@ -58,7 +58,7 @@ func (m *Manager) HandleAddProxyConfig(w http.ResponseWriter, r *http.Request) {
 		Timeout:              timeout,
 		UseTCP:               useTCP,
 		UseUDP:               useUDP,
-		ProxyProtocolVersion: ProxyProtocolVersion,
+		ProxyProtocolVersion: convertIntToProxyProtocolVersion(ProxyProtocolVersion),
 		EnableLogging:        enableLogging,
 	})
 

src/mod/streamproxy/streamproxy.go

@@ -15,13 +15,22 @@ import (
 )
 
 /*
-	TCP Proxy
+	Stream Proxy
 
 	Forward port from one port to another
 	Also accept active connection and passive
 	connection
 */
 
+// ProxyProtocolVersion enum type
+type ProxyProtocolVersion int
+
+const (
+	ProxyProtocolDisabled ProxyProtocolVersion = 0
+	ProxyProtocolV1       ProxyProtocolVersion = 1
+	ProxyProtocolV2       ProxyProtocolVersion = 2
+)
+
 type ProxyRelayOptions struct {
 	Name                 string
 	ListeningAddr        string
@@ -29,7 +38,7 @@ type ProxyRelayOptions struct {
 	Timeout              int
 	UseTCP               bool
 	UseUDP               bool
-	ProxyProtocolVersion int
+	ProxyProtocolVersion ProxyProtocolVersion
 	EnableLogging        bool
 }
 
@@ -56,7 +65,7 @@ type ProxyRelayInstance struct {
 	ProxyTargetAddr      string               //Proxy target address
 	UseTCP               bool                 //Enable TCP proxy
 	UseUDP               bool                 //Enable UDP proxy
-	ProxyProtocolVersion int    //Proxy Protocol v1/v2
+	ProxyProtocolVersion ProxyProtocolVersion //Proxy Protocol v1/v2
 	EnableLogging        bool                 //Enable logging for ProxyInstance
 	Timeout              int                  //Timeout for connection in sec
 
@@ -203,6 +212,30 @@ func (m *Manager) GetConfigByUUID(configUUID string) (*ProxyRelayInstance, error
 	return nil, errors.New("config not found")
 }
 
+// ConvertIntToProxyProtocolVersion converts an int to ProxyProtocolVersion type
+func convertIntToProxyProtocolVersion(v int) ProxyProtocolVersion {
+	switch v {
+	case 1:
+		return ProxyProtocolV1
+	case 2:
+		return ProxyProtocolV2
+	default:
+		return ProxyProtocolDisabled
+	}
+}
+
+// convertProxyProtocolVersionToInt converts ProxyProtocolVersion type back to int
+func convertProxyProtocolVersionToInt(v ProxyProtocolVersion) int {
+	switch v {
+	case ProxyProtocolV1:
+		return 1
+	case ProxyProtocolV2:
+		return 2
+	default:
+		return 0
+	}
+}
+
 // Edit the config based on config UUID, leave empty for unchange fields
 func (m *Manager) EditConfig(newConfig *ProxyRuleUpdateConfig) error {
 	// Find the config with the specified UUID
@@ -224,7 +257,7 @@ func (m *Manager) EditConfig(newConfig *ProxyRuleUpdateConfig) error {
 
 	foundConfig.UseTCP = newConfig.UseTCP
 	foundConfig.UseUDP = newConfig.UseUDP
-	foundConfig.ProxyProtocolVersion = newConfig.ProxyProtocolVersion
+	foundConfig.ProxyProtocolVersion = convertIntToProxyProtocolVersion(newConfig.ProxyProtocolVersion)
 	foundConfig.EnableLogging = newConfig.EnableLogging
 
 	if newConfig.NewTimeout != -1 {

src/mod/streamproxy/tcpprox.go

@@ -46,7 +46,7 @@ func (c *ProxyRelayInstance) connCopy(conn1 net.Conn, conn2 net.Conn, wg *sync.W
 	wg.Done()
 }
 
-func WriteProxyProtocolHeader(dst net.Conn, src net.Conn, version int) error {
+func WriteProxyProtocolHeader(dst net.Conn, src net.Conn, version ProxyProtocolVersion) error {
 	clientAddr, ok1 := src.RemoteAddr().(*net.TCPAddr)
 	proxyAddr, ok2 := src.LocalAddr().(*net.TCPAddr)
 	if !ok1 || !ok2 {
@@ -54,7 +54,7 @@ func WriteProxyProtocolHeader(dst net.Conn, src net.Conn, version int) error {
 	}
 
 	header := proxyproto.Header{
-		Version:           byte(version),
+		Version:           byte(convertProxyProtocolVersionToInt(version)),
 		Command:           proxyproto.PROXY,
 		TransportProtocol: proxyproto.TCPv4,
 		SourceAddr:        clientAddr,
@@ -165,7 +165,7 @@ func (c *ProxyRelayInstance) Port2host(allowPort string, targetAddress string, s
 			}
 			c.LogMsg("[→] connect target address ["+targetAddress+"] success.", nil)
 
-			if c.ProxyProtocolVersion != 0 {
+			if c.ProxyProtocolVersion != ProxyProtocolDisabled {
 				c.LogMsg("[+] write proxy protocol header to target address ["+targetAddress+"]", nil)
 				err = WriteProxyProtocolHeader(target, conn, c.ProxyProtocolVersion)
 				if err != nil {

src/mod/streamproxy/udpprox.go

@@ -88,7 +88,7 @@ func (c *ProxyRelayInstance) CloseAllUDPConnections() {
 // Write Proxy Protocol v2 header to UDP connection
 func WriteProxyProtocolHeaderUDP(conn *net.UDPConn, srcAddr, dstAddr *net.UDPAddr) error {
 	header := proxyproto.Header{
-		Version:           2,
+		Version:           byte(ProxyProtocolV2),
 		Command:           proxyproto.PROXY,
 		TransportProtocol: proxyproto.UDPv4,
 		SourceAddr:        srcAddr,
@@ -164,7 +164,7 @@ func (c *ProxyRelayInstance) ForwardUDP(address1, address2 string, stopChan chan
 			go c.RunUDPConnectionRelay(conn, lisener)
 
 			// Send Proxy Protocol header if enabled
-			if c.ProxyProtocolVersion == 2 {
+			if c.ProxyProtocolVersion == ProxyProtocolV2 {
 				_ = WriteProxyProtocolHeaderUDP(conn.ServerConn, cliaddr, targetAddr)
 			}
 		} else {

src/web/components/streamprox.html

@@ -90,6 +90,9 @@
                     <option value="2">Proxy Protocol V2</option>
                 </select>
                 <small>Select Proxy Protocol v1 / v2 to use (if any)</small>
+                    <div id="proxyProtocolUdpWarning" style="display:none; color:#bd7100; margin-top:0.5em;">
+                        <i class="exclamation triangle icon"></i> Proxy Protocol V1 is not supported for UDP. The proxy protocol header will not be included in UDP packets if selected.
+                    </div>
             </div>
             <button id="addStreamProxyButton" class="ui basic button" type="submit"><i class="ui green add icon"></i> Create</button>  
             <button id="editStreamProxyButton" class="ui basic button" onclick="confirmEditTCPProxyConfig(event, this);" style="display:none;"><i class="ui green check icon"></i> Update</button>  
@@ -100,6 +103,21 @@
     <script>
         let editingStreamProxyConfigUUID = ""; //The current editing TCP Proxy config UUID
 
+        // Show/hide warning for Proxy Protocol V1 + UDP
+        function updateProxyProtocolUdpWarning() {
+            const proxyProtocolVersion = $("#streamProxyForm select[name=proxyProtocolVersion]").val();
+            const useUDP = $("#streamProxyForm input[name=useUDP]")[0].checked;
+            if (proxyProtocolVersion === "1" && useUDP) {
+                $("#proxyProtocolUdpWarning").show();
+            } else {
+                $("#proxyProtocolUdpWarning").hide();
+            }
+        }
+
+        $("#streamProxyForm select[name=proxyProtocolVersion]").on("change", updateProxyProtocolUdpWarning);
+        $("#streamProxyForm input[name=useUDP]").on("change", updateProxyProtocolUdpWarning);
+        $(document).ready(updateProxyProtocolUdpWarning);
+
         $("#streamProxyForm .dropdown").dropdown();
         $('#streamProxyForm').on('submit', function(event) {
             event.preventDefault();