Refactoring: move tuntap and icmpv6 into separate package

src/tuntap/tun_windows.go

@@ -0,0 +1,99 @@
+package tuntap
+
+import (
+	"fmt"
+	"os/exec"
+	"strings"
+
+	water "github.com/yggdrasil-network/water"
+)
+
+// This is to catch Windows platforms
+
+// Configures the TAP adapter with the correct IPv6 address and MTU. On Windows
+// we don't make use of a direct operating system API to do this - we instead
+// delegate the hard work to "netsh".
+func (tun *TunAdapter) setup(ifname string, iftapmode bool, addr string, mtu int) error {
+	if !iftapmode {
+		tun.core.log.Warnln("TUN mode is not supported on this platform, defaulting to TAP")
+	}
+	config := water.Config{DeviceType: water.TAP}
+	config.PlatformSpecificParams.ComponentID = "tap0901"
+	config.PlatformSpecificParams.Network = "169.254.0.1/32"
+	if ifname == "auto" {
+		config.PlatformSpecificParams.InterfaceName = ""
+	} else {
+		config.PlatformSpecificParams.InterfaceName = ifname
+	}
+	iface, err := water.New(config)
+	if err != nil {
+		panic(err)
+	}
+	// Disable/enable the interface to resets its configuration (invalidating iface)
+	cmd := exec.Command("netsh", "interface", "set", "interface", iface.Name(), "admin=DISABLED")
+	tun.core.log.Printf("netsh command: %v", strings.Join(cmd.Args, " "))
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		tun.core.log.Errorf("Windows netsh failed: %v.", err)
+		tun.core.log.Traceln(string(output))
+		return err
+	}
+	cmd = exec.Command("netsh", "interface", "set", "interface", iface.Name(), "admin=ENABLED")
+	tun.core.log.Printf("netsh command: %v", strings.Join(cmd.Args, " "))
+	output, err = cmd.CombinedOutput()
+	if err != nil {
+		tun.core.log.Errorf("Windows netsh failed: %v.", err)
+		tun.core.log.Traceln(string(output))
+		return err
+	}
+	// Get a new iface
+	iface, err = water.New(config)
+	if err != nil {
+		panic(err)
+	}
+	tun.iface = iface
+	tun.mtu = getSupportedMTU(mtu)
+	err = tun.setupMTU(tun.mtu)
+	if err != nil {
+		panic(err)
+	}
+	// Friendly output
+	tun.core.log.Infof("Interface name: %s", tun.iface.Name())
+	tun.core.log.Infof("Interface IPv6: %s", addr)
+	tun.core.log.Infof("Interface MTU: %d", tun.mtu)
+	return tun.setupAddress(addr)
+}
+
+// Sets the MTU of the TAP adapter.
+func (tun *TunAdapter) setupMTU(mtu int) error {
+	// Set MTU
+	cmd := exec.Command("netsh", "interface", "ipv6", "set", "subinterface",
+		fmt.Sprintf("interface=%s", tun.iface.Name()),
+		fmt.Sprintf("mtu=%d", mtu),
+		"store=active")
+	tun.core.log.Debugln("netsh command: %v", strings.Join(cmd.Args, " "))
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		tun.core.log.Errorf("Windows netsh failed: %v.", err)
+		tun.core.log.Traceln(string(output))
+		return err
+	}
+	return nil
+}
+
+// Sets the IPv6 address of the TAP adapter.
+func (tun *TunAdapter) setupAddress(addr string) error {
+	// Set address
+	cmd := exec.Command("netsh", "interface", "ipv6", "add", "address",
+		fmt.Sprintf("interface=%s", tun.iface.Name()),
+		fmt.Sprintf("addr=%s", addr),
+		"store=active")
+	tun.core.log.Debugln("netsh command: %v", strings.Join(cmd.Args, " "))
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		tun.core.log.Errorf("Windows netsh failed: %v.", err)
+		tun.core.log.Traceln(string(output))
+		return err
+	}
+	return nil
+}