Fix Windows firewall message check (#1254)

The no rules matched message is operating system language specific, and can cause errors

Now we check if firewall is reachable by the app and then if the rule is returned or not in two different calls:

isWindowsFirewallReachable

isFirewallRuleActive

client/firewall/uspfilter/allow_netbird_windows.go

@@ -1,21 +1,19 @@
 package uspfilter
 
 import (
-	"errors"
 	"fmt"
 	"os/exec"
-	"strings"
 	"syscall"
+
+	log "github.com/sirupsen/logrus"
 )
 
 type action string
 
 const (
-	addRule    action = "add"
+	addRule          action = "add"
-	deleteRule action = "delete"
+	deleteRule       action = "delete"
-
+	firewallRuleName        = "Netbird"
-	firewallRuleName     = "Netbird"
-	noRulesMatchCriteria = "No rules match the specified criteria"
 )
 
 // Reset firewall to the default state
@@ -26,6 +24,14 @@ func (m *Manager) Reset() error {
 	m.outgoingRules = make(map[string]RuleSet)
 	m.incomingRules = make(map[string]RuleSet)
 
+	if !isWindowsFirewallReachable() {
+		return nil
+	}
+
+	if !isFirewallRuleActive(firewallRuleName) {
+		return nil
+	}
+
 	if err := manageFirewallRule(firewallRuleName, deleteRule); err != nil {
 		return fmt.Errorf("couldn't remove windows firewall: %w", err)
 	}
@@ -35,6 +41,13 @@ func (m *Manager) Reset() error {
 
 // AllowNetbird allows netbird interface traffic
 func (m *Manager) AllowNetbird() error {
+	if !isWindowsFirewallReachable() {
+		return nil
+	}
+
+	if isFirewallRuleActive(firewallRuleName) {
+		return nil
+	}
 	return manageFirewallRule(firewallRuleName,
 		addRule,
 		"dir=in",
@@ -45,47 +58,37 @@ func (m *Manager) AllowNetbird() error {
 	)
 }
 
-func manageFirewallRule(ruleName string, action action, args ...string) error {
+func manageFirewallRule(ruleName string, action action, extraArgs ...string) error {
-	active, err := isFirewallRuleActive(ruleName)
+
-	if err != nil {
+	args := []string{"advfirewall", "firewall", string(action), "rule", "name=" + ruleName}
-		return err
+	if action == addRule {
+		args = append(args, extraArgs...)
 	}
 
-	if (action == addRule && !active) || (action == deleteRule && active) {
+	cmd := exec.Command("netsh", args...)
-		baseArgs := []string{"advfirewall", "firewall", string(action), "rule", "name=" + ruleName}
+	cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
-		args := append(baseArgs, args...)
+	return cmd.Run()
-
-		cmd := exec.Command("netsh", args...)
-		cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
-		return cmd.Run()
-	}
-
-	return nil
 }
 
-func isFirewallRuleActive(ruleName string) (bool, error) {
+func isWindowsFirewallReachable() bool {
+	args := []string{"advfirewall", "show", "allprofiles", "state"}
+	cmd := exec.Command("netsh", args...)
+	cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
+
+	_, err := cmd.Output()
+	if err != nil {
+		log.Infof("Windows firewall is not reachable, skipping default rule management. Using only user space rules. Error: %s", err)
+		return false
+	}
+
+	return true
+}
+
+func isFirewallRuleActive(ruleName string) bool {
 	args := []string{"advfirewall", "firewall", "show", "rule", "name=" + ruleName}
 
 	cmd := exec.Command("netsh", args...)
 	cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
-	output, err := cmd.Output()
+	_, err := cmd.Output()
-	if err != nil {
+	return err == nil
-		var exitError *exec.ExitError
-		if errors.As(err, &exitError) {
-			// if the firewall rule is not active, we expect last exit code to be 1
-			exitStatus := exitError.Sys().(syscall.WaitStatus).ExitStatus()
-			if exitStatus == 1 {
-				if strings.Contains(string(output), noRulesMatchCriteria) {
-					return false, nil
-				}
-			}
-		}
-		return false, err
-	}
-
-	if strings.Contains(string(output), noRulesMatchCriteria) {
-		return false, nil
-	}
-
-	return true, nil
 }

client/internal/acl/manager_create.go

@@ -20,7 +20,7 @@ func Create(iface IFaceMapper) (manager *DefaultManager, err error) {
 			return nil, err
 		}
 		if err := fm.AllowNetbird(); err != nil {
-			log.Errorf("failed to allow netbird interface traffic: %v", err)
+			log.Warnf("failed to allow netbird interface traffic: %v", err)
 		}
 		return newDefaultManager(fm), nil
 	}