wgengine/router: on Windows, add a firewall rule to allow Tailscale

Updates tailscale/tailscale#454
This commit is contained in:
Brad Fitzpatrick 2020-09-08 13:10:20 -07:00
parent 688f923db1
commit 913c1bd04f

View File

@ -7,6 +7,8 @@
import (
"fmt"
"log"
"os/exec"
"syscall"
winipcfg "github.com/tailscale/winipcfg-go"
"github.com/tailscale/wireguard-go/device"
@ -49,6 +51,9 @@ func newUserspaceRouter(logf logger.Logf, wgdev *device.Device, tundev tun.Devic
func (r *winRouter) Up() error {
// MonitorDefaultRoutes handles making sure our wireguard UDP
// traffic goes through the old route, not recursively through the VPN.
r.removeFirewallAcceptRule()
var err error
r.routeChangeCallback, err = monitorDefaultRoutes(r.wgdev, true, r.nativeTun)
if err != nil {
@ -57,11 +62,38 @@ func (r *winRouter) Up() error {
return nil
}
// removeFirewallAcceptRule removes the "Tailscale-In" firewall rule.
//
// If it doesn't already exist, this currently returns an error but TODO: it should not.
//
// So callers should ignore its error for now.
func (r *winRouter) removeFirewallAcceptRule() error {
cmd := exec.Command("netsh", "advfirewall", "firewall", "delete", "rule", "name=Tailscale-In", "dir=in")
cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
return cmd.Run()
}
func (r *winRouter) addFirewallAcceptRule(ipStr string) error {
cmd := exec.Command("netsh", "advfirewall", "firewall", "add", "rule", "name=Tailscale-In", "dir=in", "action=allow", "localip="+ipStr, "profile=private", "enable=yes")
cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
return cmd.Run()
}
func (r *winRouter) Set(cfg *Config) error {
if cfg == nil {
cfg = &shutdownConfig
}
r.removeFirewallAcceptRule()
if len(cfg.LocalAddrs) == 1 && cfg.LocalAddrs[0].Bits == 32 {
ipStr := cfg.LocalAddrs[0].IP.String()
if err := r.addFirewallAcceptRule(ipStr); err != nil {
r.logf("addFirewallRule(%q): %v", ipStr, err)
} else {
r.logf("added firewall rule Tailscale-In for %v", ipStr)
}
}
err := configureInterface(cfg, r.nativeTun)
if err != nil {
r.logf("ConfigureInterface: %v", err)
@ -76,6 +108,8 @@ func (r *winRouter) Set(cfg *Config) error {
}
func (r *winRouter) Close() error {
r.removeFirewallAcceptRule()
if err := r.dns.Down(); err != nil {
return fmt.Errorf("dns down: %w", err)
}