feat(portforwarding): VPN_PORT_FORWARDING_DOWN_COMMAND option

internal/portforward/loop.go

@@ -44,6 +44,7 @@ func NewLoop(settings settings.PortForwarding, routing Routing,
 				Enabled:       settings.Enabled,
 				Filepath:      *settings.Filepath,
 				UpCommand:     *settings.UpCommand,
+				DownCommand:   *settings.DownCommand,
 				ListeningPort: *settings.ListeningPort,
 			},
 		},

internal/portforward/service/command.go

@@ -9,7 +9,7 @@ import (
 	"github.com/qdm12/gluetun/internal/command"
 )
 
-func runUpCommand(ctx context.Context, cmder Cmder, logger Logger,
+func runCommand(ctx context.Context, cmder Cmder, logger Logger,
 	commandTemplate string, ports []uint16,
 ) (err error) {
 	portStrings := make([]string, len(ports))

internal/portforward/service/command_test.go

@@ -11,7 +11,7 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
-func Test_Service_runUpCommand(t *testing.T) {
+func Test_Service_runCommand(t *testing.T) {
 	t.Parallel()
 	ctrl := gomock.NewController(t)
 
@@ -22,7 +22,7 @@ func Test_Service_runUpCommand(t *testing.T) {
 	logger := NewMockLogger(ctrl)
 	logger.EXPECT().Info("1234,5678")
 
-	err := runUpCommand(ctx, cmder, logger, commandTemplate, ports)
+	err := runCommand(ctx, cmder, logger, commandTemplate, ports)
 
 	require.NoError(t, err)
 }

internal/portforward/service/settings.go

@@ -13,6 +13,7 @@ type Settings struct {
 	PortForwarder  PortForwarder
 	Filepath       string
 	UpCommand      string
+	DownCommand    string
 	Interface      string // needed for PIA, PrivateVPN and ProtonVPN, tun0 for example
 	ServerName     string // needed for PIA
 	CanPortForward bool   // needed for PIA
@@ -26,6 +27,7 @@ func (s Settings) Copy() (copied Settings) {
 	copied.PortForwarder = s.PortForwarder
 	copied.Filepath = s.Filepath
 	copied.UpCommand = s.UpCommand
+	copied.DownCommand = s.DownCommand
 	copied.Interface = s.Interface
 	copied.ServerName = s.ServerName
 	copied.CanPortForward = s.CanPortForward
@@ -40,6 +42,7 @@ func (s *Settings) OverrideWith(update Settings) {
 	s.PortForwarder = gosettings.OverrideWithComparable(s.PortForwarder, update.PortForwarder)
 	s.Filepath = gosettings.OverrideWithComparable(s.Filepath, update.Filepath)
 	s.UpCommand = gosettings.OverrideWithComparable(s.UpCommand, update.UpCommand)
+	s.DownCommand = gosettings.OverrideWithComparable(s.DownCommand, update.DownCommand)
 	s.Interface = gosettings.OverrideWithComparable(s.Interface, update.Interface)
 	s.ServerName = gosettings.OverrideWithComparable(s.ServerName, update.ServerName)
 	s.CanPortForward = gosettings.OverrideWithComparable(s.CanPortForward, update.CanPortForward)

internal/portforward/service/start.go

@@ -74,7 +74,7 @@ func (s *Service) Start(ctx context.Context) (runError <-chan error, err error)
 	s.portMutex.Unlock()
 
 	if s.settings.UpCommand != "" {
-		err = runUpCommand(ctx, s.cmder, s.logger, s.settings.UpCommand, ports)
+		err = runCommand(ctx, s.cmder, s.logger, s.settings.UpCommand, ports)
 		if err != nil {
 			err = fmt.Errorf("running up command: %w", err)
 			s.logger.Error(err.Error())

internal/portforward/service/stop.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"fmt"
 	"os"
+	"time"
 )
 
 func (s *Service) Stop() (err error) {
@@ -30,6 +31,17 @@ func (s *Service) cleanup() (err error) {
 	s.portMutex.Lock()
 	defer s.portMutex.Unlock()
 
+	if s.settings.DownCommand != "" {
+		const downTimeout = 60 * time.Second
+		ctx, cancel := context.WithTimeout(context.Background(), downTimeout)
+		defer cancel()
+		err = runCommand(ctx, s.cmder, s.logger, s.settings.DownCommand, s.ports)
+		if err != nil {
+			err = fmt.Errorf("running down command: %w", err)
+			s.logger.Error(err.Error())
+		}
+	}
+
 	for _, port := range s.ports {
 		err = s.portAllower.RemoveAllowedPort(context.Background(), port)
 		if err != nil {