Tried to add syscall forward to udptunnel from tunnelexec

holepunchudptunnel/tunnelman/tunnelexec.go

@@ -6,6 +6,7 @@ import (
 	"io/ioutil"
 	"os"
 	"os/exec"
+	"syscall"
 	"path/filepath"
 	"go.uber.org/zap"
 )
@@ -156,3 +157,21 @@ func removeCopiedFile(l *zap.Logger, filePath string) {
 	}
 	l.Info("Copied file removed successfully.")
 }
+
+func forwardSignalToChild(l *zap.Logger, sig os.Signal) {
+	// Get PID of child executable
+	pid := os.Getpid()
+
+	// Create a process group with the same process group ID as the parent
+	err := syscall.Setpgid(pid, pid)
+	if err != nil {
+		l.Fatal("Error setting process group ID:"+err.Error())
+		return
+	}
+
+	// Forward the signal to the child process group
+	err = syscall.Kill(-pid, sig.(syscall.Signal))
+	if err != nil {
+		l.Error("Error forwarding signal to child process:"+err.Error())
+	}
+}

holepunchudptunnel/tunnelman/tunnelman.go

@@ -4,6 +4,7 @@ import (
 	"sort"
 	"strings"
     "syscall"
+	"os/signal"
     "golang.org/x/term"
 	"io/ioutil"
 	"os"
@@ -97,10 +98,23 @@ func (m* TunnelManager) OpenTunnel(Self, SelfPort, Client string) {
 	}
 	m.l.Info("Wrote configuration file for UDP tunnel")
 
-	//? Next: summon tunnel UDP with sudo
+	// Summon tunnel UDP with sudo
 	m.l.Info("Starting Tunnel Daemon now")
-	executeEmbeddedBinaryAsSudo(m.l, embeddedExecutable, "udptunnel", "udptunnel_config.json", passwd, "udptunnel_config.json")
-
+
+	// Create channel to recieve signals
+	signalChan := make(chan os.Signal, 1)
+	signal.Notify(signalChan, os.Interrupt, syscall.SIGTERM)
+	// Execute embedded binary with sudo in a separate goroutine
+	go executeEmbeddedBinaryAsSudo(m.l, embeddedExecutable, "udptunnel", "udptunnel_config.json", passwd, "udptunnel_config.json")
+	// Wait for signals
+	select {
+	case sig := <-signalChan:
+		m.l.Warn("Recieved signal: "+sig.String())
+		// Forward signal to child process
+		forwardSignalToChild(m.l, sig)
+	}
+
+	// if tunnels are leftover due to improper teardown, remove with: sudo ip link delete tun0
 
 }