fix(pia): port forward using server hostname instead of gateway ip

Author: qdm12

internal/models/connection.go

@@ -15,21 +15,19 @@ type Connection struct {
 	Protocol string `json:"protocol"`
 	// Hostname is used for IPVanish, IVPN, Privado
 	// and Windscribe for TLS verification.
+	// It is used for PIA for port forwarding.
 	Hostname string `json:"hostname"`
 	// PubKey is the public key of the VPN server,
 	// used only for Wireguard.
 	PubKey string `json:"pubkey"`
-	// ServerName is used for PIA for port forwarding
-	ServerName string `json:"server_name,omitempty"`
 	// PortForward is used for PIA for port forwarding
 	PortForward bool `json:"port_forward"`
 }
 
 func (c *Connection) Equal(other Connection) bool {
 	return c.IP.Compare(other.IP) == 0 && c.Port == other.Port &&
 		c.Protocol == other.Protocol && c.Hostname == other.Hostname &&
-		c.PubKey == other.PubKey && c.ServerName == other.ServerName &&
-		c.PortForward == other.PortForward
+		c.PubKey == other.PubKey && c.PortForward == other.PortForward
 }
 
 // UpdateEmptyWith updates each field of the connection where the

internal/portforward/service/settings.go

@@ -13,7 +13,7 @@ type Settings struct {
 	PortForwarder  PortForwarder
 	Filepath       string
 	Interface      string // needed for PIA and ProtonVPN, tun0 for example
-	ServerName     string // needed for PIA
+	ServerHostname string // needed for PIA
 	CanPortForward bool   // needed for PIA
 	ListeningPort  uint16
 }
@@ -23,7 +23,7 @@ func (s Settings) Copy() (copied Settings) {
 	copied.PortForwarder = s.PortForwarder
 	copied.Filepath = s.Filepath
 	copied.Interface = s.Interface
-	copied.ServerName = s.ServerName
+	copied.ServerHostname = s.ServerHostname
 	copied.CanPortForward = s.CanPortForward
 	copied.ListeningPort = s.ListeningPort
 	return copied
@@ -34,16 +34,16 @@ func (s *Settings) OverrideWith(update Settings) {
 	s.PortForwarder = gosettings.OverrideWithComparable(s.PortForwarder, update.PortForwarder)
 	s.Filepath = gosettings.OverrideWithComparable(s.Filepath, update.Filepath)
 	s.Interface = gosettings.OverrideWithComparable(s.Interface, update.Interface)
-	s.ServerName = gosettings.OverrideWithComparable(s.ServerName, update.ServerName)
+	s.ServerHostname = gosettings.OverrideWithComparable(s.ServerHostname, update.ServerHostname)
 	s.CanPortForward = gosettings.OverrideWithComparable(s.CanPortForward, update.CanPortForward)
 	s.ListeningPort = gosettings.OverrideWithComparable(s.ListeningPort, update.ListeningPort)
 }
 
 var (
-	ErrPortForwarderNotSet = errors.New("port forwarder not set")
-	ErrServerNameNotSet    = errors.New("server name not set")
-	ErrFilepathNotSet      = errors.New("file path not set")
-	ErrInterfaceNotSet     = errors.New("interface not set")
+	ErrPortForwarderNotSet  = errors.New("port forwarder not set")
+	ErrServerHostnameNotSet = errors.New("server hostname not set")
+	ErrFilepathNotSet       = errors.New("file path not set")
+	ErrInterfaceNotSet      = errors.New("interface not set")
 )
 
 func (s *Settings) Validate(forStartup bool) (err error) {
@@ -64,8 +64,8 @@ func (s *Settings) Validate(forStartup bool) (err error) {
 		return fmt.Errorf("%w", ErrPortForwarderNotSet)
 	case s.Interface == "":
 		return fmt.Errorf("%w", ErrInterfaceNotSet)
-	case s.PortForwarder.Name() == providers.PrivateInternetAccess && s.ServerName == "":
-		return fmt.Errorf("%w", ErrServerNameNotSet)
+	case s.PortForwarder.Name() == providers.PrivateInternetAccess && s.ServerHostname == "":
+		return fmt.Errorf("%w", ErrServerHostnameNotSet)
 	}
 	return nil
 }

internal/portforward/service/start.go

@@ -26,7 +26,7 @@ func (s *Service) Start(ctx context.Context) (runError <-chan error, err error)
 		Logger:         s.logger,
 		Gateway:        gateway,
 		Client:         s.client,
-		ServerName:     s.settings.ServerName,
+		ServerHostname: s.settings.ServerHostname,
 		CanPortForward: s.settings.CanPortForward,
 	}
 	port, err := s.settings.PortForwarder.PortForward(ctx, obj)

internal/provider/privateinternetaccess/httpclient.go

@@ -9,7 +9,6 @@ import (
 	"io"
 	"net"
 	"net/http"
-	"net/netip"
 	"net/url"
 	"os"
 	"strconv"
@@ -27,14 +26,11 @@ var (
 // PortForward obtains a VPN server side port forwarded from PIA.
 func (p *Provider) PortForward(ctx context.Context,
 	objects utils.PortForwardObjects) (port uint16, err error) {
-	switch {
-	case objects.ServerName == "":
-		panic("server name cannot be empty")
-	case !objects.Gateway.IsValid():
-		panic("gateway is not set")
+	if objects.ServerHostname == "" {
+		panic("server hostname cannot be empty")
 	}
 
-	serverName := objects.ServerName
+	serverName := objects.ServerHostname
 
 	logger := objects.Logger
 
@@ -43,11 +39,6 @@ func (p *Provider) PortForward(ctx context.Context,
 		return 0, nil
 	}
 
-	privateIPClient, err := newHTTPClient(serverName)
-	if err != nil {
-		return 0, fmt.Errorf("creating custom HTTP client: %w", err)
-	}
-
 	data, err := readPIAPortForwardData(p.portForwardPath)
 	if err != nil {
 		return 0, fmt.Errorf("reading saved port forwarded data: %w", err)
@@ -66,8 +57,7 @@ func (p *Provider) PortForward(ctx context.Context,
 	}
 
 	if !dataFound || expired {
-		client := objects.Client
-		data, err = refreshPIAPortForwardData(ctx, client, privateIPClient, objects.Gateway,
+		data, err = refreshPIAPortForwardData(ctx, objects.Client, objects.ServerHostname,
 			p.portForwardPath, p.authFilePath)
 		if err != nil {
 			return 0, fmt.Errorf("refreshing port forward data: %w", err)
@@ -77,7 +67,7 @@ func (p *Provider) PortForward(ctx context.Context,
 	logger.Info("Port forwarded data expires in " + format.FriendlyDuration(durationToExpiration))
 
 	// First time binding
-	if err := bindPort(ctx, privateIPClient, objects.Gateway, data); err != nil {
+	if err := bindPort(ctx, objects.Client, objects.ServerHostname, data); err != nil {
 		return 0, fmt.Errorf("binding port: %w", err)
 	}
 
@@ -90,16 +80,8 @@ var (
 
 func (p *Provider) KeepPortForward(ctx context.Context,
 	objects utils.PortForwardObjects) (err error) {
-	switch {
-	case objects.ServerName == "":
-		panic("server name cannot be empty")
-	case !objects.Gateway.IsValid():
-		panic("gateway is not set")
-	}
-
-	privateIPClient, err := newHTTPClient(objects.ServerName)
-	if err != nil {
-		return fmt.Errorf("creating custom HTTP client: %w", err)
+	if objects.ServerHostname == "" {
+		panic("server hostname cannot be empty")
 	}
 
 	data, err := readPIAPortForwardData(p.portForwardPath)
@@ -124,7 +106,7 @@ func (p *Provider) KeepPortForward(ctx context.Context,
 			}
 			return ctx.Err()
 		case <-keepAliveTimer.C:
-			err = bindPort(ctx, privateIPClient, objects.Gateway, data)
+			err = bindPort(ctx, objects.Client, objects.ServerHostname, data)
 			if err != nil {
 				return fmt.Errorf("binding port: %w", err)
 			}
@@ -136,14 +118,14 @@ func (p *Provider) KeepPortForward(ctx context.Context,
 	}
 }
 
-func refreshPIAPortForwardData(ctx context.Context, client, privateIPClient *http.Client,
-	gateway netip.Addr, portForwardPath, authFilePath string) (data piaPortForwardData, err error) {
+func refreshPIAPortForwardData(ctx context.Context, client *http.Client,
+	serverHostname, portForwardPath, authFilePath string) (data piaPortForwardData, err error) {
 	data.Token, err = fetchToken(ctx, client, authFilePath)
 	if err != nil {
 		return data, fmt.Errorf("fetching token: %w", err)
 	}
 
-	data.Port, data.Signature, data.Expiration, err = fetchPortForwardData(ctx, privateIPClient, gateway, data.Token)
+	data.Port, data.Signature, data.Expiration, err = fetchPortForwardData(ctx, client, serverHostname, data.Token)
 	if err != nil {
 		return data, fmt.Errorf("fetching port forwarding data: %w", err)
 	}
@@ -319,15 +301,15 @@ func getOpenvpnCredentials(authFilePath string) (
 	return username, password, nil
 }
 
-func fetchPortForwardData(ctx context.Context, client *http.Client, gateway netip.Addr, token string) (
+func fetchPortForwardData(ctx context.Context, client *http.Client, serverHostname, token string) (
 	port uint16, signature string, expiration time.Time, err error) {
 	errSubstitutions := map[string]string{url.QueryEscape(token): "<token>"}
 
 	queryParams := make(url.Values)
 	queryParams.Add("token", token)
 	url := url.URL{
 		Scheme:   "https",
-		Host:     net.JoinHostPort(gateway.String(), "19999"),
+		Host:     net.JoinHostPort(serverHostname, "19999"),
 		Path:     "/getSignature",
 		RawQuery: queryParams.Encode(),
 	}
@@ -373,7 +355,7 @@ var (
 	ErrBadResponse = errors.New("bad response received")
 )
 
-func bindPort(ctx context.Context, client *http.Client, gateway netip.Addr, data piaPortForwardData) (err error) {
+func bindPort(ctx context.Context, client *http.Client, serverHostname string, data piaPortForwardData) (err error) {
 	payload, err := packPayload(data.Port, data.Token, data.Expiration)
 	if err != nil {
 		return fmt.Errorf("serializing payload: %w", err)
@@ -384,7 +366,7 @@ func bindPort(ctx context.Context, client *http.Client, gateway netip.Addr, data
 	queryParams.Add("signature", data.Signature)
 	bindPortURL := url.URL{
 		Scheme:   "https",
-		Host:     net.JoinHostPort(gateway.String(), "19999"),
+		Host:     net.JoinHostPort(serverHostname, "19999"),
 		Path:     "/bindPort",
 		RawQuery: queryParams.Encode(),
 	}

internal/provider/privateinternetaccess/httpclient_test.go

@@ -65,7 +65,6 @@ func GetConnection(provider string,
 				Port:        port,
 				Protocol:    protocol,
 				Hostname:    hostname,
-				ServerName:  server.ServerName,
 				PortForward: server.PortForward,
 				PubKey:      server.WgPubKey, // Wireguard
 			}

internal/provider/privateinternetaccess/portforward.go

@@ -10,13 +10,12 @@ import (
 type PortForwardObjects struct {
 	// Logger is a logger, used by both Private Internet Access and ProtonVPN.
 	Logger Logger
-	// Gateway is the VPN gateway IP address, used by Private Internet Access
-	// and ProtonVPN.
+	// Gateway is the VPN gateway IP address, used by ProtonVPN.
 	Gateway netip.Addr
 	// Client is used to query the VPN gateway for Private Internet Access.
 	Client *http.Client
-	// ServerName is used by Private Internet Access for port forwarding.
-	ServerName string
+	// ServerHostname is used by Private Internet Access for port forwarding.
+	ServerHostname string
 	// CanPortForward is used by Private Internet Access for port forwarding.
 	CanPortForward bool
 }