chore(all): replace netlink library for more flexibility (#3107)

internal/netlink/wireguard_linux.go

@@ -1,35 +1,58 @@
 package netlink
 
 import (
+	"errors"
+	"fmt"
+	"os"
+
+	"github.com/mdlayher/genetlink"
 	"github.com/qdm12/gluetun/internal/mod"
-	"github.com/vishvananda/netlink"
 )
 
-func (n *NetLink) IsWireguardSupported() bool {
+func (n *NetLink) IsWireguardSupported() (ok bool, err error) {
 	// Check for Wireguard family without loading the wireguard module.
 	// Some kernels have the wireguard module built-in, and don't have a
 	// modules directory, such as WSL2 kernels.
-	ok := hasWireguardFamily()
-	if ok {
-		return true
+	ok, err = hasWireguardFamily()
+	if err != nil {
+		return false, fmt.Errorf("checking wireguard family: %w", err)
+	} else if ok {
+		return true, nil
 	}
 
 	// Try loading the wireguard module, since some systems do not load
 	// it after a boot. If this fails, wireguard is assumed to not be supported.
 	n.debugLogger.Debugf("wireguard family not found, trying to load wireguard kernel module")
-	err := mod.Probe("wireguard")
+	err = mod.Probe("wireguard")
 	if err != nil {
 		n.debugLogger.Debugf("failed loading wireguard kernel module: %s", err)
-		return false
+		return false, nil
 	}
 	n.debugLogger.Debugf("wireguard kernel module loaded successfully")
 
 	// Re-check if the Wireguard family is now available, after loading
 	// the wireguard kernel module.
-	return hasWireguardFamily()
+	ok, err = hasWireguardFamily()
+	if err != nil {
+		return false, fmt.Errorf("checking wireguard family: %w", err)
+	}
+	return ok, nil
 }
 
-func hasWireguardFamily() bool {
-	_, err := netlink.GenlFamilyGet("wireguard")
-	return err == nil
+func hasWireguardFamily() (ok bool, err error) {
+	conn, err := genetlink.Dial(nil)
+	if err != nil {
+		return false, fmt.Errorf("dialing netlink: %w", err)
+	}
+	defer conn.Close()
+
+	_, err = conn.GetFamily("wireguard")
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			return false, nil
+		}
+		return false, fmt.Errorf("getting wireguard family: %w", err)
+	}
+
+	return true, nil
 }