Dummy file

client/cmd/login.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"os"
 	"os/user"
+	"runtime"
 	"strings"
 
 	log "github.com/sirupsen/logrus"
@@ -120,7 +121,7 @@ func doDaemonLogin(ctx context.Context, cmd *cobra.Command, providedSetupKey str
 	loginRequest := proto.LoginRequest{
 		SetupKey:            providedSetupKey,
 		ManagementUrl:       managementURL,
-		IsUnixDesktopClient: util.HasGraphicalSession(),
+		IsUnixDesktopClient: isUnixRunningDesktop(),
 		Hostname:            hostName,
 		DnsLabels:           dnsLabelsReq,
 		ProfileName:         &handle,
@@ -188,8 +189,7 @@ func doExtendSession(ctx context.Context, cmd *cobra.Command) error {
 
 	client := proto.NewDaemonServiceClient(conn)
 
-	// the CLI runs in the user's session, the daemon does not: tell it what we can see
-	req := &proto.RequestExtendAuthSessionRequest{HasGraphicalSession: util.HasGraphicalSession()}
+	req := &proto.RequestExtendAuthSessionRequest{}
 	// Pre-fill the IdP login hint from the active profile so the user
 	// doesn't have to retype their email. Best-effort: we still proceed
 	// without a hint if the lookup fails.
@@ -408,13 +408,8 @@ func foregroundGetTokenInfo(ctx context.Context, cmd *cobra.Command, config *pro
 		hint = profileState.Email
 	}
 
-	oAuthFlow, err := auth.NewOAuthFlow(ctx, config, util.HasGraphicalSession(), false, hint)
+	oAuthFlow, err := auth.NewOAuthFlow(ctx, config, isUnixRunningDesktop(), false, hint)
 	if err != nil {
-		// enrolling a device is the one flow a setup key can replace
-		if auth.IsSSOUnavailable(err) {
-			return nil, fmt.Errorf("%w. Set this device up with a setup key instead: "+
-				"https://docs.netbird.io/how-to/register-machines-using-setup-keys", err)
-		}
 		return nil, err
 	}
 
@@ -463,6 +458,14 @@ func openURL(cmd *cobra.Command, verificationURIComplete, userCode string, noBro
 	}
 }
 
+// isUnixRunningDesktop checks if a Linux OS is running desktop environment
+func isUnixRunningDesktop() bool {
+	if runtime.GOOS != "linux" && runtime.GOOS != "freebsd" {
+		return false
+	}
+	return os.Getenv("DESKTOP_SESSION") != "" || os.Getenv("XDG_CURRENT_DESKTOP") != ""
+}
+
 func setEnvAndFlags(cmd *cobra.Command) error {
 	SetFlagsFromEnvVars(rootCmd)
 

client/cmd/up.go

@@ -21,8 +21,8 @@ import (
 	"github.com/netbirdio/netbird/client/internal"
 	"github.com/netbirdio/netbird/client/internal/peer"
 	"github.com/netbirdio/netbird/client/internal/profilemanager"
-	nbnet "github.com/netbirdio/netbird/client/net"
 	"github.com/netbirdio/netbird/client/proto"
+	nbnet "github.com/netbirdio/netbird/client/net"
 	"github.com/netbirdio/netbird/client/server"
 	"github.com/netbirdio/netbird/client/system"
 	"github.com/netbirdio/netbird/shared/management/domain"
@@ -626,7 +626,7 @@ func setupLoginRequest(providedSetupKey string, customDNSAddressConverted []byte
 		NatExternalIPs:      natExternalIPs,
 		CleanNATExternalIPs: natExternalIPs != nil && len(natExternalIPs) == 0,
 		CustomDNSAddress:    customDNSAddressConverted,
-		IsUnixDesktopClient: util.HasGraphicalSession(),
+		IsUnixDesktopClient: isUnixRunningDesktop(),
 		Hostname:            hostName,
 		ExtraIFaceBlacklist: extraIFaceBlackList,
 		DnsLabels:           dnsLabels,

client/firewall/iptables/dnat_refcount_linux_test.go

@@ -1,240 +0,0 @@
-//go:build privileged
-
-package iptables
-
-import (
-	"net/netip"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	fw "github.com/netbirdio/netbird/client/firewall/manager"
-	"github.com/netbirdio/netbird/client/iface"
-	"github.com/netbirdio/netbird/client/iface/wgaddr"
-)
-
-func iptRefcountIfaceV4() *iFaceMock {
-	return &iFaceMock{
-		NameFunc: func() string { return "wt-refcount" },
-		AddressFunc: func() wgaddr.Address {
-			return wgaddr.Address{
-				IP:      netip.MustParseAddr("10.20.0.1"),
-				Network: netip.MustParsePrefix("10.20.0.0/24"),
-			}
-		},
-	}
-}
-
-func iptRefcountIfaceDual() *iFaceMock {
-	return &iFaceMock{
-		NameFunc: func() string { return "wt-refcount" },
-		AddressFunc: func() wgaddr.Address {
-			return wgaddr.Address{
-				IP:      netip.MustParseAddr("10.20.0.1"),
-				Network: netip.MustParsePrefix("10.20.0.0/24"),
-				IPv6:    netip.MustParseAddr("fd00::1"),
-				IPv6Net: netip.MustParsePrefix("fd00::/64"),
-			}
-		},
-	}
-}
-
-func newIptRefcountManager(t *testing.T, dual bool) *Manager {
-	t.Helper()
-	var ifMock *iFaceMock
-	if dual {
-		ifMock = iptRefcountIfaceDual()
-	} else {
-		ifMock = iptRefcountIfaceV4()
-	}
-	m, err := Create(ifMock, iface.DefaultMTU)
-	require.NoError(t, err, "create manager")
-	require.NoError(t, m.Init(nil), "init manager")
-	t.Cleanup(func() {
-		require.NoError(t, m.Close(nil), "close manager")
-	})
-	return m
-}
-
-func iptDnatV4(port uint16) fw.ForwardRule {
-	return fw.ForwardRule{
-		Protocol:          fw.ProtocolTCP,
-		DestinationPort:   fw.Port{Values: []uint16{port}},
-		TranslatedAddress: netip.MustParseAddr("10.20.0.2"),
-		TranslatedPort:    fw.Port{Values: []uint16{80}},
-	}
-}
-
-func iptDnatV6(port uint16) fw.ForwardRule {
-	return fw.ForwardRule{
-		Protocol:          fw.ProtocolTCP,
-		DestinationPort:   fw.Port{Values: []uint16{port}},
-		TranslatedAddress: netip.MustParseAddr("fd00::2"),
-		TranslatedPort:    fw.Port{Values: []uint16{80}},
-	}
-}
-
-// TestIptablesRouting_RepeatedEnableSingleReference verifies that EnableRouting
-// (called on every network-map update) holds at most one reference per family
-// and a single DisableRouting drops both back to zero.
-func TestIptablesRouting_RepeatedEnableSingleReference(t *testing.T) {
-	m := newIptRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	require.NoError(t, m.EnableRouting(), "first enable")
-	require.NoError(t, m.EnableRouting(), "second enable")
-	require.NoError(t, m.EnableRouting(), "third enable")
-	v4, v6 := state.Counts()
-	assert.Equal(t, 1, v4, "repeated enable holds a single v4 reference")
-	assert.Equal(t, 1, v6, "repeated enable holds a single v6 reference")
-
-	require.NoError(t, m.DisableRouting(), "disable")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4, "single disable releases the v4 reference")
-	assert.Equal(t, 0, v6, "single disable releases the v6 reference")
-}
-
-// TestIptablesRouting_DisableKeepsDNATReference verifies that an unpaired
-// DisableRouting does not release references held by active DNAT rules.
-func TestIptablesRouting_DisableKeepsDNATReference(t *testing.T) {
-	m := newIptRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	r1, err := m.AddDNATRule(iptDnatV6(9095))
-	require.NoError(t, err, "add v6 dnat")
-
-	require.NoError(t, m.DisableRouting(), "unpaired disable")
-	_, v6 := state.Counts()
-	assert.Equal(t, 1, v6, "DNAT-held reference survives unpaired DisableRouting")
-
-	require.NoError(t, m.DeleteDNATRule(r1), "delete v6 dnat")
-	_, v6 = state.Counts()
-	assert.Equal(t, 0, v6, "delete releases the DNAT reference")
-}
-
-// TestIptablesDNAT_RefcountBalancedV4 covers a Balanced Add/Delete pair on v4.
-func TestIptablesDNAT_RefcountBalancedV4(t *testing.T) {
-	m := newIptRefcountManager(t, false)
-	state := m.router.ipFwdState
-
-	r1, err := m.AddDNATRule(iptDnatV4(7081))
-	require.NoError(t, err, "add v4 dnat 1")
-	v4, v6 := state.Counts()
-	assert.Equal(t, 1, v4, "v4 refcount after first add")
-	assert.Equal(t, 0, v6, "v6 refcount unchanged")
-
-	r2, err := m.AddDNATRule(iptDnatV4(7082))
-	require.NoError(t, err, "add v4 dnat 2")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 2, v4, "v4 refcount after second add")
-	assert.Equal(t, 0, v6, "v6 refcount unchanged")
-
-	require.NoError(t, m.DeleteDNATRule(r1))
-	v4, v6 = state.Counts()
-	assert.Equal(t, 1, v4, "v4 refcount after first delete")
-	assert.Equal(t, 0, v6, "v6 refcount unchanged")
-
-	require.NoError(t, m.DeleteDNATRule(r2))
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4, "v4 refcount after second delete")
-	assert.Equal(t, 0, v6, "v6 refcount unchanged")
-}
-
-// TestIptablesDNAT_RefcountBalancedV6 checks the v6 path increments v6 only and
-// decrements back to zero.
-func TestIptablesDNAT_RefcountBalancedV6(t *testing.T) {
-	m := newIptRefcountManager(t, true)
-	require.NotNil(t, m.router6, "v6 router")
-	require.Same(t, m.router.ipFwdState, m.router6.ipFwdState, "shared state")
-	state := m.router.ipFwdState
-
-	r1, err := m.AddDNATRule(iptDnatV6(9081))
-	require.NoError(t, err, "add v6 dnat 1")
-	v4, v6 := state.Counts()
-	assert.Equal(t, 0, v4)
-	assert.Equal(t, 1, v6, "v6 refcount after first add")
-
-	r2, err := m.AddDNATRule(iptDnatV6(9082))
-	require.NoError(t, err, "add v6 dnat 2")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4, "v4 refcount unchanged")
-	assert.Equal(t, 2, v6, "v6 refcount after second add")
-
-	require.NoError(t, m.DeleteDNATRule(r1))
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4, "v4 refcount unchanged")
-	assert.Equal(t, 1, v6, "v6 refcount after first delete")
-
-	require.NoError(t, m.DeleteDNATRule(r2))
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4)
-	assert.Equal(t, 0, v6, "v6 refcount after second delete")
-}
-
-// TestIptablesDNAT_DuplicateAddNoLeak verifies the duplicate-rule path returns
-// without bumping the refcount.
-func TestIptablesDNAT_DuplicateAddNoLeak(t *testing.T) {
-	m := newIptRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	rule := iptDnatV4(7083)
-	r1, err := m.AddDNATRule(rule)
-	require.NoError(t, err)
-	v4, _ := state.Counts()
-	assert.Equal(t, 1, v4)
-
-	_, err = m.AddDNATRule(rule)
-	require.NoError(t, err, "duplicate add")
-	v4, _ = state.Counts()
-	assert.Equal(t, 1, v4, "duplicate add must not increment")
-
-	require.NoError(t, m.DeleteDNATRule(r1))
-	v4, _ = state.Counts()
-	assert.Equal(t, 0, v4, "single delete must drop to zero")
-}
-
-// TestIptablesDNAT_DeleteMissingNoUnderflow verifies Delete on an unknown rule
-// neither errors nor releases the refcount.
-func TestIptablesDNAT_DeleteMissingNoUnderflow(t *testing.T) {
-	m := newIptRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	phantom := iptDnatV4(7099)
-	require.NoError(t, m.DeleteDNATRule(&phantom), "delete missing v4")
-	v4, v6 := state.Counts()
-	assert.Equal(t, 0, v4)
-	assert.Equal(t, 0, v6)
-
-	phantom6 := iptDnatV6(9099)
-	require.NoError(t, m.DeleteDNATRule(&phantom6), "delete missing v6")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4)
-	assert.Equal(t, 0, v6)
-
-	r1, err := m.AddDNATRule(iptDnatV4(7100))
-	require.NoError(t, err)
-	v4, _ = state.Counts()
-	assert.Equal(t, 1, v4, "real add still increments after phantom delete")
-	require.NoError(t, m.DeleteDNATRule(r1))
-}
-
-// TestIptablesDNAT_DoubleDeleteNoUnderflow verifies a second Delete on the same
-// rule is a no-op.
-func TestIptablesDNAT_DoubleDeleteNoUnderflow(t *testing.T) {
-	m := newIptRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	r1, err := m.AddDNATRule(iptDnatV6(9083))
-	require.NoError(t, err)
-	_, v6 := state.Counts()
-	assert.Equal(t, 1, v6)
-
-	require.NoError(t, m.DeleteDNATRule(r1), "first delete")
-	_, v6 = state.Counts()
-	assert.Equal(t, 0, v6)
-
-	require.NoError(t, m.DeleteDNATRule(r1), "second delete must be no-op")
-	_, v6 = state.Counts()
-	assert.Equal(t, 0, v6, "double delete must not underflow")
-}

client/firewall/iptables/manager_linux.go

@@ -89,7 +89,7 @@ func (m *Manager) createIPv6Components(wgIface iFaceMapper, mtu uint16) error {
 	}
 
 	// Share the same IP forwarding state with the v4 router, since
-	// Forwarding refcounter is per-family but shared between v4 and v6 routers.
+	// EnableIPForwarding controls both v4 and v6 sysctls.
 	m.router6.ipFwdState = m.router.ipFwdState
 
 	m.aclMgr6, err = newAclManager(ip6Client, wgIface)
@@ -402,12 +402,17 @@ func (m *Manager) SetLogLevel(log.Level) {
 }
 
 func (m *Manager) EnableRouting() error {
-	// v6 only when the overlay actually has v6.
-	return m.router.ipFwdState.RequestRouting(m.router6 != nil)
+	if err := m.router.ipFwdState.RequestForwarding(); err != nil {
+		return fmt.Errorf("enable IP forwarding: %w", err)
+	}
+	return nil
 }
 
 func (m *Manager) DisableRouting() error {
-	return m.router.ipFwdState.ReleaseRouting()
+	if err := m.router.ipFwdState.ReleaseForwarding(); err != nil {
+		return fmt.Errorf("disable IP forwarding: %w", err)
+	}
+	return nil
 }
 
 // AddDNATRule adds a DNAT rule

client/firewall/iptables/router_linux.go

@@ -102,7 +102,7 @@ func newRouter(iptablesClient *iptables.IPTables, wgIface iFaceMapper, mtu uint1
 		wgIface:        wgIface,
 		mtu:            mtu,
 		v6:             iptablesClient.Proto() == iptables.ProtocolIPv6,
-		ipFwdState:     ipfwdstate.NewIPForwardingState(wgIface.Name()),
+		ipFwdState:     ipfwdstate.NewIPForwardingState(),
 	}
 
 	r.ipsetCounter = refcounter.New(
@@ -770,6 +770,10 @@ func (r *router) updateState() {
 }
 
 func (r *router) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error) {
+	if err := r.ipFwdState.RequestForwarding(); err != nil {
+		return nil, err
+	}
+
 	ruleKey := rule.ID()
 	if _, exists := r.rules[ruleKey+dnatSuffix]; exists {
 		return rule, nil
@@ -836,34 +840,18 @@ func (r *router) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error) {
 
 	for key, ruleInfo := range rules {
 		if err := r.iptablesClient.Append(ruleInfo.table, ruleInfo.chain, ruleInfo.rule...); err != nil {
-			r.cleanupFailedDNATAdd(rules)
+			if rollbackErr := r.rollbackRules(rules); rollbackErr != nil {
+				log.Errorf("rollback failed: %v", rollbackErr)
+			}
 			return nil, fmt.Errorf("add rule %s: %w", key, err)
 		}
 		r.rules[key] = ruleInfo.rule
 	}
 
-	if err := r.ipFwdState.RequestForwarding(r.v6); err != nil {
-		r.cleanupFailedDNATAdd(rules)
-		return nil, fmt.Errorf("enable forwarding: %w", err)
-	}
-
 	r.updateState()
 	return rule, nil
 }
 
-// cleanupFailedDNATAdd removes the bookkeeping written by a partially applied
-// AddDNATRule before rolling back the kernel rules, so no entries remain that
-// never got a forwarding refcount. rollbackRules re-adds entries it failed to
-// remove from the kernel.
-func (r *router) cleanupFailedDNATAdd(rules map[string]ruleInfo) {
-	for key := range rules {
-		delete(r.rules, key)
-	}
-	if err := r.rollbackRules(rules); err != nil {
-		log.Errorf("rollback failed: %v", err)
-	}
-}
-
 func (r *router) rollbackRules(rules map[string]ruleInfo) error {
 	var merr *multierror.Error
 	for key, ruleInfo := range rules {
@@ -880,47 +868,32 @@ func (r *router) rollbackRules(rules map[string]ruleInfo) error {
 }
 
 func (r *router) DeleteDNATRule(rule firewall.Rule) error {
-	ruleKey := rule.ID()
-
-	_, hadDNAT := r.rules[ruleKey+dnatSuffix]
-	_, hadSNAT := r.rules[ruleKey+snatSuffix]
-	_, hadFWD := r.rules[ruleKey+fwdSuffix]
-	if !hadDNAT && !hadSNAT && !hadFWD {
-		return nil
+	if err := r.ipFwdState.ReleaseForwarding(); err != nil {
+		log.Errorf("%v", err)
 	}
 
+	ruleKey := rule.ID()
+
 	var merr *multierror.Error
 	if dnatRule, exists := r.rules[ruleKey+dnatSuffix]; exists {
 		if err := r.iptablesClient.Delete(tableNat, chainRTRDR, dnatRule...); err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("delete DNAT rule: %w", err))
-		} else {
-			delete(r.rules, ruleKey+dnatSuffix)
 		}
+		delete(r.rules, ruleKey+dnatSuffix)
 	}
 
 	if snatRule, exists := r.rules[ruleKey+snatSuffix]; exists {
 		if err := r.iptablesClient.Delete(tableNat, chainRTNAT, snatRule...); err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("delete SNAT rule: %w", err))
-		} else {
-			delete(r.rules, ruleKey+snatSuffix)
 		}
+		delete(r.rules, ruleKey+snatSuffix)
 	}
 
 	if fwdRule, exists := r.rules[ruleKey+fwdSuffix]; exists {
 		if err := r.iptablesClient.Delete(tableFilter, chainRTFWDOUT, fwdRule...); err != nil {
 			merr = multierror.Append(merr, fmt.Errorf("delete forward rule: %w", err))
-		} else {
-			delete(r.rules, ruleKey+fwdSuffix)
-		}
-	}
-
-	// Release the refcount only once all rules are gone from the kernel. On
-	// partial failure the failed entries stay in r.rules so a retry can remove
-	// them and release then.
-	if merr == nil {
-		if err := r.ipFwdState.ReleaseForwarding(r.v6); err != nil {
-			log.Errorf("%v", err)
 		}
+		delete(r.rules, ruleKey+fwdSuffix)
 	}
 
 	r.updateState()

client/firewall/nftables/dnat_refcount_linux_test.go

@@ -1,249 +0,0 @@
-//go:build privileged
-
-package nftables
-
-import (
-	"net/netip"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-
-	fw "github.com/netbirdio/netbird/client/firewall/manager"
-	"github.com/netbirdio/netbird/client/iface"
-	"github.com/netbirdio/netbird/client/iface/wgaddr"
-)
-
-func nftRefcountIfaceV4() *iFaceMock {
-	return &iFaceMock{
-		NameFunc: func() string { return "wt-refcount" },
-		AddressFunc: func() wgaddr.Address {
-			return wgaddr.Address{
-				IP:      netip.MustParseAddr("100.96.0.1"),
-				Network: netip.MustParsePrefix("100.96.0.0/16"),
-			}
-		},
-	}
-}
-
-func nftRefcountIfaceDual() *iFaceMock {
-	return &iFaceMock{
-		NameFunc: func() string { return "wt-refcount" },
-		AddressFunc: func() wgaddr.Address {
-			return wgaddr.Address{
-				IP:      netip.MustParseAddr("100.96.0.1"),
-				Network: netip.MustParsePrefix("100.96.0.0/16"),
-				IPv6:    netip.MustParseAddr("fd00::1"),
-				IPv6Net: netip.MustParsePrefix("fd00::/64"),
-			}
-		},
-	}
-}
-
-func newNftRefcountManager(t *testing.T, dual bool) *Manager {
-	t.Helper()
-	if check() != NFTABLES {
-		t.Skip("nftables not supported on this system")
-	}
-	var ifMock *iFaceMock
-	if dual {
-		ifMock = nftRefcountIfaceDual()
-	} else {
-		ifMock = nftRefcountIfaceV4()
-	}
-	m, err := Create(ifMock, iface.DefaultMTU)
-	require.NoError(t, err, "create manager")
-	require.NoError(t, m.Init(nil), "init manager")
-	t.Cleanup(func() {
-		require.NoError(t, m.Close(nil), "close manager")
-	})
-	return m
-}
-
-func dnatV4(port uint16) fw.ForwardRule {
-	return fw.ForwardRule{
-		Protocol:          fw.ProtocolTCP,
-		DestinationPort:   fw.Port{Values: []uint16{port}},
-		TranslatedAddress: netip.MustParseAddr("100.96.0.2"),
-		TranslatedPort:    fw.Port{Values: []uint16{80}},
-	}
-}
-
-func dnatV6(port uint16) fw.ForwardRule {
-	return fw.ForwardRule{
-		Protocol:          fw.ProtocolTCP,
-		DestinationPort:   fw.Port{Values: []uint16{port}},
-		TranslatedAddress: netip.MustParseAddr("fd00::2"),
-		TranslatedPort:    fw.Port{Values: []uint16{80}},
-	}
-}
-
-// TestNftablesDNAT_RefcountBalancedV4 verifies that Add/Delete pairs leave the
-// v4 refcount at zero.
-func TestNftablesDNAT_RefcountBalancedV4(t *testing.T) {
-	m := newNftRefcountManager(t, false)
-	state := m.router.ipFwdState
-
-	r1, err := m.AddDNATRule(dnatV4(8081))
-	require.NoError(t, err, "add v4 dnat 1")
-	v4, v6 := state.Counts()
-	assert.Equal(t, 1, v4, "v4 refcount after first add")
-	assert.Equal(t, 0, v6, "v6 refcount unchanged")
-
-	r2, err := m.AddDNATRule(dnatV4(8082))
-	require.NoError(t, err, "add v4 dnat 2")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 2, v4, "v4 refcount after second add")
-	assert.Equal(t, 0, v6, "v6 refcount unchanged")
-
-	require.NoError(t, m.DeleteDNATRule(r1), "delete v4 dnat 1")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 1, v4, "v4 refcount after first delete")
-	assert.Equal(t, 0, v6, "v6 refcount unchanged")
-
-	require.NoError(t, m.DeleteDNATRule(r2), "delete v4 dnat 2")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4, "v4 refcount after second delete")
-	assert.Equal(t, 0, v6, "v6 refcount unchanged")
-}
-
-// TestNftablesDNAT_RefcountBalancedV6 verifies the v6 path increments v6 only
-// and decrements back to zero on Delete.
-func TestNftablesDNAT_RefcountBalancedV6(t *testing.T) {
-	m := newNftRefcountManager(t, true)
-	require.NotNil(t, m.router6, "v6 router")
-	require.Same(t, m.router.ipFwdState, m.router6.ipFwdState, "shared state")
-	state := m.router.ipFwdState
-
-	r1, err := m.AddDNATRule(dnatV6(9091))
-	require.NoError(t, err, "add v6 dnat 1")
-	v4, v6 := state.Counts()
-	assert.Equal(t, 0, v4, "v4 refcount unchanged")
-	assert.Equal(t, 1, v6, "v6 refcount after first add")
-
-	r2, err := m.AddDNATRule(dnatV6(9092))
-	require.NoError(t, err, "add v6 dnat 2")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4)
-	assert.Equal(t, 2, v6, "v6 refcount after second add")
-
-	require.NoError(t, m.DeleteDNATRule(r1), "delete v6 dnat 1")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4, "v4 refcount unchanged")
-	assert.Equal(t, 1, v6, "v6 refcount after first delete")
-
-	require.NoError(t, m.DeleteDNATRule(r2), "delete v6 dnat 2")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4)
-	assert.Equal(t, 0, v6, "v6 refcount after second delete")
-}
-
-// TestNftablesDNAT_DuplicateAddNoLeak verifies that a duplicate Add (same
-// ForwardRule) does not double-increment the refcount.
-func TestNftablesDNAT_DuplicateAddNoLeak(t *testing.T) {
-	m := newNftRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	rule := dnatV4(8083)
-	r1, err := m.AddDNATRule(rule)
-	require.NoError(t, err, "add v4 dnat")
-	v4, _ := state.Counts()
-	assert.Equal(t, 1, v4)
-
-	// duplicate add: same rule ID, must be a no-op for the refcount.
-	_, err = m.AddDNATRule(rule)
-	require.NoError(t, err, "duplicate add")
-	v4, _ = state.Counts()
-	assert.Equal(t, 1, v4, "duplicate add must not increment")
-
-	require.NoError(t, m.DeleteDNATRule(r1), "delete v4 dnat")
-	v4, _ = state.Counts()
-	assert.Equal(t, 0, v4, "single delete must drop to zero")
-}
-
-// TestNftablesDNAT_DeleteMissingNoUnderflow verifies deleting a rule that was
-// never added does not underflow the refcount.
-func TestNftablesDNAT_DeleteMissingNoUnderflow(t *testing.T) {
-	m := newNftRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	// Construct a Rule reference for something never added. The router stores
-	// rules by ID(), and DeleteDNATRule looks them up in r.rules; a missing
-	// entry must be a no-op rather than calling Release.
-	phantom := dnatV4(8099)
-	require.NoError(t, m.DeleteDNATRule(&phantom), "delete missing v4 dnat")
-	v4, v6 := state.Counts()
-	assert.Equal(t, 0, v4, "v4 refcount unaffected by missing delete")
-	assert.Equal(t, 0, v6, "v6 refcount unaffected")
-
-	phantom6 := dnatV6(9099)
-	require.NoError(t, m.DeleteDNATRule(&phantom6), "delete missing v6 dnat")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4)
-	assert.Equal(t, 0, v6, "v6 refcount unaffected by missing delete")
-
-	// And after a phantom delete, a real add still results in count=1.
-	r1, err := m.AddDNATRule(dnatV4(8100))
-	require.NoError(t, err, "add v4 dnat after phantom delete")
-	v4, _ = state.Counts()
-	assert.Equal(t, 1, v4, "real add still increments after phantom delete")
-	require.NoError(t, m.DeleteDNATRule(r1))
-}
-
-// TestNftablesRouting_RepeatedEnableSingleReference verifies that EnableRouting
-// (called on every network-map update) holds at most one reference per family
-// and a single DisableRouting drops both back to zero.
-func TestNftablesRouting_RepeatedEnableSingleReference(t *testing.T) {
-	m := newNftRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	require.NoError(t, m.EnableRouting(), "first enable")
-	require.NoError(t, m.EnableRouting(), "second enable")
-	require.NoError(t, m.EnableRouting(), "third enable")
-	v4, v6 := state.Counts()
-	assert.Equal(t, 1, v4, "repeated enable holds a single v4 reference")
-	assert.Equal(t, 1, v6, "repeated enable holds a single v6 reference")
-
-	require.NoError(t, m.DisableRouting(), "disable")
-	v4, v6 = state.Counts()
-	assert.Equal(t, 0, v4, "single disable releases the v4 reference")
-	assert.Equal(t, 0, v6, "single disable releases the v6 reference")
-}
-
-// TestNftablesRouting_DisableKeepsDNATReference verifies that an unpaired
-// DisableRouting does not release references held by active DNAT rules.
-func TestNftablesRouting_DisableKeepsDNATReference(t *testing.T) {
-	m := newNftRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	r1, err := m.AddDNATRule(dnatV6(9095))
-	require.NoError(t, err, "add v6 dnat")
-
-	require.NoError(t, m.DisableRouting(), "unpaired disable")
-	_, v6 := state.Counts()
-	assert.Equal(t, 1, v6, "DNAT-held reference survives unpaired DisableRouting")
-
-	require.NoError(t, m.DeleteDNATRule(r1), "delete v6 dnat")
-	_, v6 = state.Counts()
-	assert.Equal(t, 0, v6, "delete releases the DNAT reference")
-}
-
-// TestNftablesDNAT_DoubleDeleteNoUnderflow verifies that deleting the same rule
-// twice does not underflow the refcount (the second delete is a no-op).
-func TestNftablesDNAT_DoubleDeleteNoUnderflow(t *testing.T) {
-	m := newNftRefcountManager(t, true)
-	state := m.router.ipFwdState
-
-	r1, err := m.AddDNATRule(dnatV6(9093))
-	require.NoError(t, err)
-	_, v6 := state.Counts()
-	assert.Equal(t, 1, v6)
-
-	require.NoError(t, m.DeleteDNATRule(r1), "first delete")
-	_, v6 = state.Counts()
-	assert.Equal(t, 0, v6)
-
-	require.NoError(t, m.DeleteDNATRule(r1), "second delete must be no-op")
-	_, v6 = state.Counts()
-	assert.Equal(t, 0, v6, "double delete must not underflow")
-}

client/firewall/nftables/manager_linux.go

@@ -105,8 +105,8 @@ func (m *Manager) createIPv6Components(tableName string, wgIface iFaceMapper, mt
 		return fmt.Errorf("create v6 router: %w", err)
 	}
 
-	// Share the per-family forwarding refcounter with the v4 router so a v4
-	// rule and a v6 rule against the same state machine cooperate cleanly.
+	// Share the same IP forwarding state with the v4 router, since
+	// EnableIPForwarding controls both v4 and v6 sysctls.
 	m.router6.ipFwdState = m.router.ipFwdState
 
 	m.aclManager6, err = newAclManager(workTable6, wgIface, chainNameRoutingFw)
@@ -530,12 +530,17 @@ func (m *Manager) SetLogLevel(log.Level) {
 }
 
 func (m *Manager) EnableRouting() error {
-	// v6 only when the overlay actually has v6.
-	return m.router.ipFwdState.RequestRouting(m.router6 != nil)
+	if err := m.router.ipFwdState.RequestForwarding(); err != nil {
+		return fmt.Errorf("enable IP forwarding: %w", err)
+	}
+	return nil
 }
 
 func (m *Manager) DisableRouting() error {
-	return m.router.ipFwdState.ReleaseRouting()
+	if err := m.router.ipFwdState.ReleaseForwarding(); err != nil {
+		return fmt.Errorf("disable IP forwarding: %w", err)
+	}
+	return nil
 }
 
 // Flush rule/chain/set operations from the buffer

client/firewall/nftables/router_linux.go

@@ -93,7 +93,7 @@ func newRouter(workTable *nftables.Table, wgIface iFaceMapper, mtu uint16) (*rou
 		rules:      make(map[string]*nftables.Rule),
 		af:         familyForAddr(workTable.Family == nftables.TableFamilyIPv4),
 		wgIface:    wgIface,
-		ipFwdState: ipfwdstate.NewIPForwardingState(wgIface.Name()),
+		ipFwdState: ipfwdstate.NewIPForwardingState(),
 		mtu:        mtu,
 	}
 
@@ -1553,6 +1553,10 @@ func (r *router) refreshRulesMap() error {
 }
 
 func (r *router) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error) {
+	if err := r.ipFwdState.RequestForwarding(); err != nil {
+		return nil, err
+	}
+
 	ruleKey := rule.ID()
 	if _, exists := r.rules[ruleKey+dnatSuffix]; exists {
 		return rule, nil
@@ -1563,18 +1567,7 @@ func (r *router) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error) {
 		return nil, fmt.Errorf("convert protocol to number: %w", err)
 	}
 
-	// Request forwarding before queueing rules: addDnatRedirect/addDnatMasq
-	// buffer netlink messages on r.conn that the next caller's Flush would
-	// commit if we returned without flushing them ourselves.
-	v6 := r.af.tableFamily == nftables.TableFamilyIPv6
-	if err := r.ipFwdState.RequestForwarding(v6); err != nil {
-		return nil, fmt.Errorf("enable forwarding: %w", err)
-	}
-
 	if err := r.addDnatRedirect(rule, protoNum, ruleKey); err != nil {
-		if rerr := r.ipFwdState.ReleaseForwarding(v6); rerr != nil {
-			log.Warnf("rollback forwarding refcount: %v", rerr)
-		}
 		return nil, err
 	}
 
@@ -1586,11 +1579,6 @@ func (r *router) AddDNATRule(rule firewall.ForwardRule) (firewall.Rule, error) {
 	// TODO: find chains with drop policies and add rules there
 
 	if err := r.conn.Flush(); err != nil {
-		if rerr := r.ipFwdState.ReleaseForwarding(v6); rerr != nil {
-			log.Warnf("rollback forwarding refcount: %v", rerr)
-		}
-		delete(r.rules, ruleKey+dnatSuffix)
-		delete(r.rules, ruleKey+snatSuffix)
 		return nil, fmt.Errorf("flush rules: %w", err)
 	}
 
@@ -1793,18 +1781,16 @@ func (r *router) addDnatMasq(rule firewall.ForwardRule, protoNum uint8, ruleKey
 }
 
 func (r *router) DeleteDNATRule(rule firewall.Rule) error {
+	if err := r.ipFwdState.ReleaseForwarding(); err != nil {
+		log.Errorf("%v", err)
+	}
+
 	ruleKey := rule.ID()
 
 	if err := r.refreshRulesMap(); err != nil {
 		return fmt.Errorf(refreshRulesMapError, err)
 	}
 
-	_, hadDNAT := r.rules[ruleKey+dnatSuffix]
-	_, hadSNAT := r.rules[ruleKey+snatSuffix]
-	if !hadDNAT && !hadSNAT {
-		return nil
-	}
-
 	var merr *multierror.Error
 	var needsFlush bool
 
@@ -1836,16 +1822,9 @@ func (r *router) DeleteDNATRule(rule firewall.Rule) error {
 		}
 	}
 
-	// Release the refcount only once the rules are gone from the kernel. On
-	// failure (including the refreshRulesMap error above) the rules and their
-	// map entries remain, keeping forwarding on until a retry removes them.
 	if merr == nil {
 		delete(r.rules, ruleKey+dnatSuffix)
 		delete(r.rules, ruleKey+snatSuffix)
-
-		if err := r.ipFwdState.ReleaseForwarding(r.af.tableFamily == nftables.TableFamilyIPv6); err != nil {
-			log.Errorf("%v", err)
-		}
 	}
 
 	return nberrors.FormatErrorOrNil(merr)

client/internal/auth/auth.go

@@ -2,7 +2,6 @@ package auth
 
 import (
 	"context"
-	"errors"
 	"net/url"
 	"strings"
 	"sync"
@@ -141,21 +140,25 @@ func (a *Auth) IsSSOSupported(ctx context.Context) (bool, error) {
 // This avoids creating a new connection to the management server
 func (a *Auth) GetOAuthFlow(ctx context.Context, forceDeviceAuth bool) (OAuthFlow, error) {
 	var flow OAuthFlow
+	var err error
 
-	// the connection is owned by a and outlives this call, so a later fallback reuses it
-	newAuth := func(context.Context) (*Auth, func(), error) {
-		return a, func() {}, nil
-	}
-
-	err := a.withRetry(ctx, func(client *mgm.GrpcClient) error {
-		var err error
-		flow, err = oauthFlowWithFallback(a, client, flowOrder(forceDeviceAuth), "", newAuth)
-
-		var ssoUnavailable *ssoUnavailableError
-		if errors.As(err, &ssoUnavailable) {
-			return backoff.Permanent(err)
+	err = a.withRetry(ctx, func(client *mgm.GrpcClient) error {
+		if forceDeviceAuth {
+			flow, err = a.getDeviceFlow(client)
+			return err
 		}
-		return err
+
+		// Try PKCE flow first
+		flow, err = a.getPKCEFlow(client)
+		if err != nil {
+			// If PKCE not supported, try Device flow
+			if s, ok := status.FromError(err); ok && (s.Code() == codes.NotFound || s.Code() == codes.Unimplemented) {
+				flow, err = a.getDeviceFlow(client)
+				return err
+			}
+			return err
+		}
+		return nil
 	})
 
 	return flow, err

client/internal/auth/device_flow.go

@@ -48,17 +48,8 @@ type DeviceAuthProviderConfig struct {
 	LoginHint string
 }
 
-// validateDeviceAuthConfig validates device authorization provider configuration. A missing
-// value means management does not have this flow configured, so the error wraps
-// errFlowNotConfigured and the caller can fall back to the other flow.
+// validateDeviceAuthConfig validates device authorization provider configuration
 func validateDeviceAuthConfig(config *DeviceAuthProviderConfig) error {
-	if err := checkDeviceAuthConfig(config); err != nil {
-		return fmt.Errorf("%w: %w", errFlowNotConfigured, err)
-	}
-	return nil
-}
-
-func checkDeviceAuthConfig(config *DeviceAuthProviderConfig) error {
 	errorMsgFormat := "invalid provider configuration received from management: %s value is empty. Contact your NetBird administrator"
 
 	if config.Audience == "" {
@@ -170,12 +161,8 @@ func (d *DeviceAuthorizationFlow) RequestAuthInfo(ctx context.Context) (AuthFlow
 		return AuthFlowInfo{}, fmt.Errorf("reading body failed with error: %v", err)
 	}
 
-	if res.StatusCode != http.StatusOK {
-		reqErr := fmt.Errorf("request device code returned status %d error: %s", res.StatusCode, string(body))
-		if deviceGrantUnsupported(res.StatusCode, body) {
-			return AuthFlowInfo{}, fmt.Errorf("%w: %w", errFlowNotConfigured, reqErr)
-		}
-		return AuthFlowInfo{}, reqErr
+	if res.StatusCode != 200 {
+		return AuthFlowInfo{}, fmt.Errorf("request device code returned status %d error: %s", res.StatusCode, string(body))
 	}
 
 	deviceCode := AuthFlowInfo{}
@@ -199,34 +186,6 @@ func (d *DeviceAuthorizationFlow) RequestAuthInfo(ctx context.Context) (AuthFlow
 	return deviceCode, err
 }
 
-// deviceGrantUnsupported reports whether the IdP's answer to a device code request means it does
-// not serve the device authorization grant at all, rather than a transient or request-specific
-// failure. An IdP that does not route the endpoint answers 404/405/501; one that knows the
-// endpoint but has the grant disabled for this client answers with an OAuth 2.0 error code.
-func deviceGrantUnsupported(statusCode int, body []byte) bool {
-	switch statusCode {
-	case http.StatusNotFound, http.StatusMethodNotAllowed, http.StatusNotImplemented:
-		return true
-	case http.StatusBadRequest, http.StatusUnauthorized, http.StatusForbidden:
-	default:
-		return false
-	}
-
-	var oauthErr struct {
-		Error string `json:"error"`
-	}
-	if err := json.Unmarshal(body, &oauthErr); err != nil {
-		return false
-	}
-
-	switch oauthErr.Error {
-	case "unsupported_grant_type", "unauthorized_client", "invalid_client":
-		return true
-	default:
-		return false
-	}
-}
-
 func appendLoginHint(uri, loginHint string) string {
 	if uri == "" || loginHint == "" {
 		return uri

client/internal/auth/oauth.go

@@ -2,19 +2,15 @@ package auth
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"net/http"
-	"net/url"
 	"runtime"
-	"sync"
 
 	log "github.com/sirupsen/logrus"
 	"google.golang.org/grpc/codes"
 	gstatus "google.golang.org/grpc/status"
 
 	"github.com/netbirdio/netbird/client/internal/profilemanager"
-	mgm "github.com/netbirdio/netbird/shared/management/client"
 )
 
 // OAuthFlow represents an interface for authorization using different OAuth 2.0 flows
@@ -63,278 +59,77 @@ func (t TokenInfo) GetTokenToUse() string {
 	return t.AccessToken
 }
 
-// errFlowNotConfigured marks a flow this deployment does not offer: management returned no
-// configuration for it, the configuration it returned is incomplete, or the IdP refuses to serve
-// the grant. It is the only condition that makes the client try the other flow, so that a
-// transient failure keeps failing on the flow the user actually wants.
-var errFlowNotConfigured = errors.New("authorization flow is not configured")
-
-// ssoUnavailableError reports that the management server offers no usable SSO flow at all.
-// Retrying cannot help, so callers should surface it to the user instead of backing off.
-type ssoUnavailableError struct {
-	msg string
+func shouldUseDeviceFlow(force bool, isUnixDesktopClient bool) bool {
+	return force || (runtime.GOOS == "linux" || runtime.GOOS == "freebsd") && !isUnixDesktopClient
 }
 
-func (e *ssoUnavailableError) Error() string {
-	return e.msg
-}
-
-// oauthFlowInit names one of the OAuth flows and builds it from the management configuration.
-type oauthFlowInit struct {
-	name string
-	init func(a *Auth, client *mgm.GrpcClient, hint string) (OAuthFlow, error)
-}
-
-// authFactory hands out a management connection to build a flow with, plus the cleanup that
-// releases it. Callers that own a long-lived connection return it with a no-op cleanup.
-type authFactory func(ctx context.Context) (*Auth, func(), error)
-
-// fallbackFlow wraps the flow that was picked at initialization time with the flows that were
-// not tried. Whether the IdP actually serves a flow only shows up when the flow is run: an IdP
-// with the device grant disabled answers the device code request with 404 even though
-// management handed out a device flow configuration. When that happens the wrapper swaps in the
-// next flow instead of failing the login.
-type fallbackFlow struct {
-	mu        sync.Mutex
-	active    OAuthFlow
-	remaining []oauthFlowInit
-	hint      string
-	newAuth   authFactory
-}
-
-func (f *fallbackFlow) RequestAuthInfo(ctx context.Context) (AuthFlowInfo, error) {
-	info, err := f.current().RequestAuthInfo(ctx)
-	if err == nil || !isFlowUnavailable(err) {
-		return info, err
-	}
-
-	next, nextErr := f.initNext(ctx)
-	if nextErr != nil {
-		log.Debugf("failed to fall back to another authorization flow: %v", nextErr)
-		return AuthFlowInfo{}, err
-	}
-
-	return next.RequestAuthInfo(ctx)
-}
-
-func (f *fallbackFlow) WaitToken(ctx context.Context, info AuthFlowInfo) (TokenInfo, error) {
-	return f.current().WaitToken(ctx, info)
-}
-
-func (f *fallbackFlow) GetClientID(ctx context.Context) string {
-	return f.current().GetClientID(ctx)
-}
-
-func (f *fallbackFlow) current() OAuthFlow {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-
-	return f.active
-}
-
-// initNext initializes the next flow this deployment offers and makes it the active one.
-func (f *fallbackFlow) initNext(ctx context.Context) (OAuthFlow, error) {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-
-	if len(f.remaining) == 0 {
-		return nil, errors.New("no authorization flow left to try")
-	}
-
-	a, cleanup, err := f.newAuth(ctx)
-	if err != nil {
-		return nil, err
-	}
-	defer cleanup()
-
-	flow, remaining, err := initFirstAvailableFlow(a, a.client, f.remaining, f.hint)
-	if err != nil {
-		return nil, err
-	}
-
-	log.Infof("the identity provider does not serve the selected authorization flow, continuing with the next one")
-	f.active = flow
-	f.remaining = remaining
-
-	return flow, nil
-}
-
-// preferDeviceFlow reports whether the device code flow should be tried before PKCE. PKCE needs
-// a browser on this host and a loopback listener to receive the redirect, neither of which
-// exists on a Unix host without a graphical session. The GOOS guard keeps a caller that reports
-// no graphical session on a platform that always has one from changing the preference.
-func preferDeviceFlow(force bool, hasGraphicalSession bool) bool {
-	return force || (runtime.GOOS == "linux" || runtime.GOOS == "freebsd") && !hasGraphicalSession
-}
-
-// flowOrder returns both flows in the order they should be attempted.
-func flowOrder(preferDevice bool) []oauthFlowInit {
-	pkce := oauthFlowInit{name: "pkce authorization flow", init: initPKCEFlow}
-	device := oauthFlowInit{name: "device code flow", init: initDeviceFlow}
-
-	if preferDevice {
-		return []oauthFlowInit{device, pkce}
-	}
-	return []oauthFlowInit{pkce, device}
-}
-
-func initPKCEFlow(a *Auth, client *mgm.GrpcClient, hint string) (OAuthFlow, error) {
-	flow, err := a.getPKCEFlow(client)
-	if err != nil {
-		return nil, err
-	}
-
-	if hint != "" {
-		flow.SetLoginHint(hint)
-	}
-
-	return flow, nil
-}
-
-func initDeviceFlow(a *Auth, client *mgm.GrpcClient, hint string) (OAuthFlow, error) {
-	flow, err := a.getDeviceFlow(client)
-	if err != nil {
-		return nil, err
-	}
-
-	if hint != "" {
-		flow.SetLoginHint(hint)
-	}
-
-	return flow, nil
-}
-
-// NewOAuthFlow initializes and returns an OAuth flow based on the management configuration.
+// NewOAuthFlow initializes and returns the appropriate OAuth flow based on the management configuration
 //
-// Both flows are optional server side: management answers NotFound for a flow it has no
-// configuration for. The preferred flow is tried first and the other one is used as a fallback,
-// so a server that only offers one of them still works. forceDeviceCodeFlow prefers the device
-// code flow regardless of platform (e.g. for Android TV).
-func NewOAuthFlow(ctx context.Context, config *profilemanager.Config, hasGraphicalSession bool, forceDeviceCodeFlow bool, hint string) (OAuthFlow, error) {
+// It starts by initializing the PKCE.If this process fails, it resorts to the Device Code Flow,
+// and if that also fails, the authentication process is deemed unsuccessful
+//
+// On Linux distros without desktop environment support, it only tries to initialize the Device Code Flow
+// forceDeviceCodeFlow can be used to skip PKCE and go directly to Device Code Flow (e.g., for Android TV)
+func NewOAuthFlow(ctx context.Context, config *profilemanager.Config, isUnixDesktopClient bool, forceDeviceCodeFlow bool, hint string) (OAuthFlow, error) {
+	if shouldUseDeviceFlow(forceDeviceCodeFlow, isUnixDesktopClient) {
+		return authenticateWithDeviceCodeFlow(ctx, config, hint)
+	}
+
+	pkceFlow, err := authenticateWithPKCEFlow(ctx, config, hint)
+	if err != nil {
+		log.Debugf("failed to initialize pkce authentication with error: %v\n", err)
+		log.Debug("falling back to device code flow")
+		return authenticateWithDeviceCodeFlow(ctx, config, hint)
+	}
+	return pkceFlow, nil
+}
+
+// authenticateWithPKCEFlow initializes the Proof Key for Code Exchange flow auth flow
+func authenticateWithPKCEFlow(ctx context.Context, config *profilemanager.Config, hint string) (OAuthFlow, error) {
 	authClient, err := NewAuth(ctx, config.PrivateKey, config.ManagementURL, config)
 	if err != nil {
-		return nil, fmt.Errorf("create auth client: %w", err)
+		return nil, fmt.Errorf("failed to create auth client: %v", err)
 	}
 	defer authClient.Close()
 
-	// the connection above is closed on return, so a later fallback opens its own
-	newAuth := func(ctx context.Context) (*Auth, func(), error) {
-		a, err := NewAuth(ctx, config.PrivateKey, config.ManagementURL, config)
-		if err != nil {
-			return nil, nil, fmt.Errorf("create auth client: %w", err)
-		}
-		return a, func() {
-			if err := a.Close(); err != nil {
-				log.Debugf("failed to close auth client: %v", err)
-			}
-		}, nil
-	}
-
-	flows := flowOrder(preferDeviceFlow(forceDeviceCodeFlow, hasGraphicalSession))
-	return oauthFlowWithFallback(authClient, authClient.client, flows, hint, newAuth)
-}
-
-// oauthFlowWithFallback initializes the first flow this deployment offers, moving on to the next
-// one when a flow is not configured here. It only fails once every flow has been tried, and any
-// flow left untried is handed to the returned flow so it can still fall back if the IdP rejects
-// the flow that was picked.
-func oauthFlowWithFallback(a *Auth, client *mgm.GrpcClient, flows []oauthFlowInit, hint string, newAuth authFactory) (OAuthFlow, error) {
-	flow, remaining, err := initFirstAvailableFlow(a, client, flows, hint)
+	pkceFlowInfo, err := authClient.getPKCEFlow(authClient.client)
 	if err != nil {
-		return nil, err
+		return nil, fmt.Errorf("getting pkce authorization flow info failed with error: %v", err)
 	}
 
-	if len(remaining) == 0 {
-		return flow, nil
+	if hint != "" {
+		pkceFlowInfo.SetLoginHint(hint)
 	}
 
-	return &fallbackFlow{
-		active:    flow,
-		remaining: remaining,
-		hint:      hint,
-		newAuth:   newAuth,
-	}, nil
+	return pkceFlowInfo, nil
 }
 
-// initFirstAvailableFlow returns the first flow that could be initialized along with the flows
-// after it, which are still untried.
-func initFirstAvailableFlow(a *Auth, client *mgm.GrpcClient, flows []oauthFlowInit, hint string) (OAuthFlow, []oauthFlowInit, error) {
-	var errs []error
-	for i, f := range flows {
-		flow, err := f.init(a, client, hint)
-		if err == nil {
-			return flow, flows[i+1:], nil
-		}
+// authenticateWithDeviceCodeFlow initializes the Device Code auth Flow
+func authenticateWithDeviceCodeFlow(ctx context.Context, config *profilemanager.Config, hint string) (OAuthFlow, error) {
+	authClient, err := NewAuth(ctx, config.PrivateKey, config.ManagementURL, config)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create auth client: %v", err)
+	}
+	defer authClient.Close()
 
-		errs = append(errs, fmt.Errorf("%s: %w", f.name, err))
-
-		// only a flow this deployment does not offer is worth replacing with another one
-		if !isFlowUnavailable(err) {
-			break
-		}
-		if i < len(flows)-1 {
-			log.Infof("%s is not configured (%v), falling back to %s", f.name, err, flows[i+1].name)
+	deviceFlowInfo, err := authClient.getDeviceFlow(authClient.client)
+	if err != nil {
+		switch s, ok := gstatus.FromError(err); {
+		case ok && s.Code() == codes.NotFound:
+			return nil, fmt.Errorf("no SSO provider returned from management. " +
+				"Please proceed with setting up this device using setup keys " +
+				"https://docs.netbird.io/how-to/register-machines-using-setup-keys")
+		case ok && s.Code() == codes.Unimplemented:
+			return nil, fmt.Errorf("the management server, %s, does not support SSO providers, "+
+				"please update your server or use Setup Keys to login", config.ManagementURL)
+		default:
+			return nil, fmt.Errorf("getting device authorization flow info failed with error: %v", err)
 		}
 	}
 
-	return nil, nil, flowInitError(a.mgmURL, errs)
-}
-
-// flowInitError turns the per-flow initialization errors into a single actionable error. The
-// message stays neutral about what to do instead: SSO is also how a peer extends its session and
-// authenticates SSH, where a setup key is no alternative. Callers that are enrolling a device add
-// that advice themselves, see IsSSOUnavailable.
-func flowInitError(mgmURL *url.URL, errs []error) error {
-	if allMatch(errs, isFlowUnimplemented) {
-		return &ssoUnavailableError{msg: fmt.Sprintf("the management server, %s, does not support SSO providers, "+
-			"please update your server", mgmURL)}
+	if hint != "" {
+		deviceFlowInfo.SetLoginHint(hint)
 	}
 
-	if allMatch(errs, isFlowUnavailable) {
-		return &ssoUnavailableError{msg: "the management server has no SSO provider configured: " +
-			"neither the pkce authorization flow nor the device code flow is available"}
-	}
-
-	return fmt.Errorf("initialize authorization flow: %w", errors.Join(errs...))
-}
-
-// IsSSOUnavailable reports whether err means the management server offers no usable SSO flow, so
-// no retry and no other flow can help. Enrollment paths use it to point the user at setup keys.
-func IsSSOUnavailable(err error) bool {
-	var ssoUnavailable *ssoUnavailableError
-	return errors.As(err, &ssoUnavailable)
-}
-
-func allMatch(errs []error, match func(error) bool) bool {
-	if len(errs) == 0 {
-		return false
-	}
-
-	for _, err := range errs {
-		if !match(err) {
-			return false
-		}
-	}
-	return true
-}
-
-// isFlowUnavailable reports whether the flow is not on offer here: management has no
-// configuration for it (NotFound), predates the RPC entirely (Unimplemented), returned an
-// incomplete configuration, or the IdP does not serve the grant.
-func isFlowUnavailable(err error) bool {
-	return errors.Is(err, errFlowNotConfigured) ||
-		hasStatusCode(err, codes.NotFound) ||
-		hasStatusCode(err, codes.Unimplemented)
-}
-
-func isFlowUnimplemented(err error) bool {
-	return hasStatusCode(err, codes.Unimplemented)
-}
-
-func hasStatusCode(err error, code codes.Code) bool {
-	s, ok := gstatus.FromError(err)
-	if !ok {
-		return false
-	}
-	return s.Code() == code
+	return deviceFlowInfo, nil
 }

client/internal/auth/oauth_test.go

@@ -1,221 +0,0 @@
-package auth
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"net/url"
-	"runtime"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-	"google.golang.org/grpc/codes"
-	"google.golang.org/grpc/status"
-
-	mgm "github.com/netbirdio/netbird/shared/management/client"
-)
-
-// stubFlow is a minimal OAuthFlow returned by the fake initializers below. requestErr, when set,
-// is what its RequestAuthInfo returns, standing in for an IdP that rejects the flow.
-type stubFlow struct {
-	name       string
-	hint       string
-	requestErr error
-}
-
-func (s *stubFlow) RequestAuthInfo(context.Context) (AuthFlowInfo, error) {
-	if s.requestErr != nil {
-		return AuthFlowInfo{}, s.requestErr
-	}
-	return AuthFlowInfo{UserCode: s.name}, nil
-}
-
-func (s *stubFlow) WaitToken(context.Context, AuthFlowInfo) (TokenInfo, error) {
-	return TokenInfo{}, nil
-}
-
-func (s *stubFlow) GetClientID(context.Context) string {
-	return ""
-}
-
-// stubInit returns a flow initializer that yields a named stub flow, or err when err is non-nil.
-func stubInit(name string, err error) oauthFlowInit {
-	return stubInitFlow(name, err, nil)
-}
-
-// stubInitFlow is stubInit with control over what the resulting flow's RequestAuthInfo returns.
-func stubInitFlow(name string, initErr, requestErr error) oauthFlowInit {
-	return oauthFlowInit{
-		name: name,
-		init: func(_ *Auth, _ *mgm.GrpcClient, hint string) (OAuthFlow, error) {
-			if initErr != nil {
-				return nil, initErr
-			}
-			return &stubFlow{name: name, hint: hint, requestErr: requestErr}, nil
-		},
-	}
-}
-
-// stubAuthFactory hands out an Auth without a management connection, which the stub
-// initializers above never touch.
-func stubAuthFactory(a *Auth) authFactory {
-	return func(context.Context) (*Auth, func(), error) {
-		return a, func() {}, nil
-	}
-}
-
-func TestOAuthFlowWithFallback(t *testing.T) {
-	notFound := status.Error(codes.NotFound, "no device authorization flow information available")
-	unimplemented := status.Error(codes.Unimplemented, "unknown method")
-	incompleteConfig := fmt.Errorf("%w: Client ID value is empty", errFlowNotConfigured)
-	unreachable := status.Error(codes.Unavailable, "connection refused")
-
-	tests := []struct {
-		name          string
-		flows         []oauthFlowInit
-		expectedFlow  string
-		expectedErr   string
-		expectedNoSSO bool
-	}{
-		{
-			name:         "preferred flow is used",
-			flows:        []oauthFlowInit{stubInit("device", nil), stubInit("pkce", nil)},
-			expectedFlow: "device",
-		},
-		{
-			// the RedHat case: device code flow disabled on management, PKCE configured
-			name:         "falls back when preferred flow is not configured",
-			flows:        []oauthFlowInit{stubInit("device", notFound), stubInit("pkce", nil)},
-			expectedFlow: "pkce",
-		},
-		{
-			name:         "falls back on an incomplete flow configuration",
-			flows:        []oauthFlowInit{stubInit("pkce", incompleteConfig), stubInit("device", nil)},
-			expectedFlow: "device",
-		},
-		{
-			name:        "does not fall back when the preferred flow fails for another reason",
-			flows:       []oauthFlowInit{stubInit("pkce", unreachable), stubInit("device", nil)},
-			expectedErr: "connection refused",
-		},
-		{
-			// stays neutral about the remedy: --extend and SSH auth cannot use a setup key
-			name:          "neither flow configured reports no SSO provider",
-			flows:         []oauthFlowInit{stubInit("device", notFound), stubInit("pkce", notFound)},
-			expectedErr:   "no SSO provider configured",
-			expectedNoSSO: true,
-		},
-		{
-			name:          "old server without the flow RPCs asks for an update",
-			flows:         []oauthFlowInit{stubInit("device", unimplemented), stubInit("pkce", unimplemented)},
-			expectedErr:   "does not support SSO providers",
-			expectedNoSSO: true,
-		},
-	}
-
-	mgmURL, err := url.Parse("https://api.netbird.io:443")
-	require.NoError(t, err)
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			a := &Auth{mgmURL: mgmURL}
-			flow, err := oauthFlowWithFallback(a, nil, tt.flows, "user@example.com", stubAuthFactory(a))
-
-			if tt.expectedErr != "" {
-				require.Error(t, err)
-				assert.Contains(t, err.Error(), tt.expectedErr)
-
-				var ssoUnavailable *ssoUnavailableError
-				assert.Equal(t, tt.expectedNoSSO, errors.As(err, &ssoUnavailable),
-					"terminal SSO-unavailable classification mismatch for %v", err)
-				return
-			}
-
-			require.NoError(t, err)
-			stub := activeStub(t, flow)
-			assert.Equal(t, tt.expectedFlow, stub.name)
-			assert.Equal(t, "user@example.com", stub.hint, "login hint must be passed to the flow")
-		})
-	}
-}
-
-// activeStub unwraps the flow currently in use, which is behind a fallbackFlow whenever an
-// untried flow is left.
-func activeStub(t *testing.T, flow OAuthFlow) *stubFlow {
-	t.Helper()
-
-	if fallback, ok := flow.(*fallbackFlow); ok {
-		flow = fallback.current()
-	}
-
-	stub, ok := flow.(*stubFlow)
-	require.True(t, ok, "unexpected flow type %T", flow)
-	return stub
-}
-
-// TestFallbackFlowRequestAuthInfo covers the failure the RedHat report hit: management hands out
-// a device flow configuration, but the IdP does not serve the grant and only says so when the
-// device code is requested.
-func TestFallbackFlowRequestAuthInfo(t *testing.T) {
-	mgmURL, err := url.Parse("https://api.netbird.io:443")
-	require.NoError(t, err)
-	a := &Auth{mgmURL: mgmURL}
-
-	idpRejects := fmt.Errorf("%w: request device code returned status 404", errFlowNotConfigured)
-
-	t.Run("swaps in the untried flow", func(t *testing.T) {
-		flows := []oauthFlowInit{stubInitFlow("device", nil, idpRejects), stubInit("pkce", nil)}
-
-		flow, err := oauthFlowWithFallback(a, nil, flows, "", stubAuthFactory(a))
-		require.NoError(t, err)
-		require.Equal(t, "device", activeStub(t, flow).name)
-
-		info, err := flow.RequestAuthInfo(context.Background())
-		require.NoError(t, err)
-		assert.Equal(t, "pkce", info.UserCode, "the request must be served by the fallback flow")
-		assert.Equal(t, "pkce", activeStub(t, flow).name, "the fallback flow must stay active for WaitToken")
-	})
-
-	t.Run("keeps the original error when nothing else is configured", func(t *testing.T) {
-		flows := []oauthFlowInit{
-			stubInitFlow("device", nil, idpRejects),
-			stubInit("pkce", status.Error(codes.NotFound, "no pkce authorization flow information available")),
-		}
-
-		flow, err := oauthFlowWithFallback(a, nil, flows, "", stubAuthFactory(a))
-		require.NoError(t, err)
-
-		_, err = flow.RequestAuthInfo(context.Background())
-		require.Error(t, err)
-		assert.Contains(t, err.Error(), "status 404")
-	})
-
-	t.Run("does not swap flows on an unrelated failure", func(t *testing.T) {
-		flows := []oauthFlowInit{
-			stubInitFlow("device", nil, errors.New("timeout talking to the IdP")),
-			stubInit("pkce", nil),
-		}
-
-		flow, err := oauthFlowWithFallback(a, nil, flows, "", stubAuthFactory(a))
-		require.NoError(t, err)
-
-		_, err = flow.RequestAuthInfo(context.Background())
-		require.Error(t, err)
-		assert.Equal(t, "device", activeStub(t, flow).name, "the preferred flow must stay active")
-	})
-}
-
-func TestFlowOrder(t *testing.T) {
-	assert.Equal(t, "pkce authorization flow", flowOrder(false)[0].name)
-	assert.Equal(t, "device code flow", flowOrder(true)[0].name)
-	assert.Len(t, flowOrder(false), 2, "both flows must always be attempted")
-}
-
-func TestPreferDeviceFlow(t *testing.T) {
-	isUnix := runtime.GOOS == "linux" || runtime.GOOS == "freebsd"
-
-	assert.True(t, preferDeviceFlow(true, true), "forced device flow wins over a desktop session")
-	assert.Equal(t, isUnix, preferDeviceFlow(false, false), "headless unix hosts prefer the device flow")
-	assert.False(t, preferDeviceFlow(false, true), "desktop clients prefer PKCE")
-}

client/internal/auth/pkce_flow.go

@@ -62,17 +62,8 @@ type PKCEAuthProviderConfig struct {
 	LoginHint string
 }
 
-// validatePKCEConfig validates PKCE provider configuration. A missing value means management
-// does not have this flow configured, so the error wraps errFlowNotConfigured and the caller can
-// fall back to the other flow.
+// validatePKCEConfig validates PKCE provider configuration
 func validatePKCEConfig(config *PKCEAuthProviderConfig) error {
-	if err := checkPKCEConfig(config); err != nil {
-		return fmt.Errorf("%w: %w", errFlowNotConfigured, err)
-	}
-	return nil
-}
-
-func checkPKCEConfig(config *PKCEAuthProviderConfig) error {
 	errorMsgFormat := "invalid provider configuration received from management: %s value is empty. Contact your NetBird administrator"
 
 	if config.ClientID == "" {

client/internal/debug/debug_linux.go

@@ -844,10 +844,6 @@ func collectSysctls() string {
 		[]string{"net.ipv4.conf.all.src_valid_mark", "net.ipv4.conf.default.src_valid_mark"},
 		listInterfaceSysctls("ipv4", "src_valid_mark")...,
 	))
-	writeSysctlGroup(&builder, "accept_ra", append(
-		[]string{"net.ipv6.conf.all.accept_ra", "net.ipv6.conf.default.accept_ra"},
-		listInterfaceSysctls("ipv6", "accept_ra")...,
-	))
 	writeSysctlGroup(&builder, "conntrack", []string{
 		"net.netfilter.nf_conntrack_acct",
 		"net.netfilter.nf_conntrack_tcp_loose",

client/internal/routemanager/ipfwdstate/ipfwdstate.go

@@ -2,183 +2,54 @@ package ipfwdstate
 
 import (
 	"fmt"
-	"sync"
 
 	log "github.com/sirupsen/logrus"
 
 	"github.com/netbirdio/netbird/client/internal/routemanager/systemops"
 )
 
-// IPForwardingState tracks v4 and v6 IP-forwarding sysctl enables with
-// independent refcounts so a v4-only routing setup doesn't flip v6 sysctls.
+// IPForwardingState is a struct that keeps track of the IP forwarding state.
+// todo: read initial state of the IP forwarding from the system and reset the state based on it.
+// todo: separate v4/v6 forwarding state, since the sysctls are independent
+// (net.ipv4.ip_forward vs net.ipv6.conf.all.forwarding). Currently the nftables
+// manager shares one instance between both routers, which works only because
+// EnableIPForwarding enables both sysctls in a single call.
 type IPForwardingState struct {
-	mu sync.Mutex
-
-	v4Count int
-	v6Count int
-
-	// routingV4/routingV6 track whether the routing path currently holds a
-	// reference, so repeated EnableRouting calls (one per network-map update)
-	// hold at most one reference per family and an unpaired DisableRouting
-	// can't release references held by DNAT rules.
-	routingV4 bool
-	routingV6 bool
-
-	wgIfaceName string
-	v6Saved     map[string]int
+	enabledCounter int
 }
 
-// NewIPForwardingState returns a state tracker for the IP-forwarding sysctls.
-// wgIfaceName is excluded from the per-interface accept_ra handling.
-func NewIPForwardingState(wgIfaceName string) *IPForwardingState {
-	return &IPForwardingState{wgIfaceName: wgIfaceName}
+func NewIPForwardingState() *IPForwardingState {
+	return &IPForwardingState{}
 }
 
-// Counts returns the current v4 and v6 refcounts. Intended for diagnostics
-// and tests.
-func (f *IPForwardingState) Counts() (v4, v6 int) {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-	return f.v4Count, f.v6Count
-}
-
-// RequestRouting takes the forwarding references for the routing path. It is
-// idempotent: while routing already holds a reference, further calls don't
-// increment the refcounts, and a v4-only request releases a previously held v6
-// reference. A v6 sysctl failure is logged and not returned so it can't take
-// down v4 routing (the sysctl may be unwritable, e.g. read-only /proc/sys or
-// IPv6 disabled on the kernel command line); v6 is retried on the next call.
-func (f *IPForwardingState) RequestRouting(v6 bool) error {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-
-	if !f.routingV4 {
-		if err := f.requestV4(); err != nil {
-			return err
-		}
-		f.routingV4 = true
-	}
-
-	if !v6 {
-		if !f.routingV6 {
-			return nil
-		}
-		f.routingV6 = false
-		return f.releaseV6()
-	}
-
-	if f.routingV6 {
-		return nil
-	}
-	if err := f.requestV6(); err != nil {
-		log.Warnf("enable IPv6 forwarding for routing: %v", err)
-		return nil
-	}
-	f.routingV6 = true
-	return nil
-}
-
-// ReleaseRouting releases the references RequestRouting holds. Calls without a
-// held reference are no-ops.
-func (f *IPForwardingState) ReleaseRouting() error {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-
-	if f.routingV4 {
-		f.routingV4 = false
-		f.releaseV4()
-	}
-	if f.routingV6 {
-		f.routingV6 = false
-		return f.releaseV6()
-	}
-	return nil
-}
-
-// RequestForwarding enables the family's forwarding sysctl on first request.
-func (f *IPForwardingState) RequestForwarding(v6 bool) error {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-
-	if v6 {
-		return f.requestV6()
-	}
-	return f.requestV4()
-}
-
-// ReleaseForwarding decrements the family counter. The last v6 release restores
-// what enable captured. v4 stays on: net.ipv4.ip_forward is co-owned by other
-// tooling (docker, k8s, libvirt).
-func (f *IPForwardingState) ReleaseForwarding(v6 bool) error {
-	f.mu.Lock()
-	defer f.mu.Unlock()
-
-	if v6 {
-		return f.releaseV6()
-	}
-	f.releaseV4()
-	return nil
-}
-
-func (f *IPForwardingState) requestV4() error {
-	if f.v4Count == 0 {
-		if err := systemops.EnableV4IPForwarding(); err != nil {
-			return fmt.Errorf("enable IPv4 forwarding: %w", err)
-		}
-		log.Info("IPv4 forwarding enabled")
-	}
-	f.v4Count++
-	return nil
-}
-
-func (f *IPForwardingState) releaseV4() {
-	if f.v4Count > 0 {
-		f.v4Count--
-	}
-}
-
-func (f *IPForwardingState) requestV6() error {
-	if f.v6Count == 0 {
-		saved, err := systemops.EnableV6IPForwarding(f.wgIfaceName)
-		if err != nil {
-			if rerr := systemops.DisableV6IPForwarding(saved); rerr != nil {
-				log.Warnf("rollback partial v6 sysctls: %v", rerr)
-			}
-			return fmt.Errorf("enable IPv6 forwarding: %w", err)
-		}
-		// A failed restore on a previous release keeps its saved values; those
-		// are the true originals, so keep them over what this enable captured.
-		if f.v6Saved == nil {
-			f.v6Saved = saved
-		} else {
-			for k, v := range saved {
-				if _, ok := f.v6Saved[k]; !ok {
-					f.v6Saved[k] = v
-				}
-			}
-		}
-		log.Info("IPv6 forwarding enabled")
-	}
-	f.v6Count++
-	return nil
-}
-
-func (f *IPForwardingState) releaseV6() error {
-	if f.v6Count == 0 {
-		return nil
-	}
-	f.v6Count--
-	if f.v6Count > 0 {
+func (f *IPForwardingState) RequestForwarding() error {
+	if f.enabledCounter != 0 {
+		f.enabledCounter++
 		return nil
 	}
 
-	// Keep the saved values on failure so a later release or enable/release
-	// cycle can still restore them; re-restoring an already-restored key is a
-	// no-op since the sysctl already holds the desired value.
-	if err := systemops.DisableV6IPForwarding(f.v6Saved); err != nil {
-		return fmt.Errorf("disable IPv6 forwarding: %w", err)
+	if err := systemops.EnableIPForwarding(); err != nil {
+		return fmt.Errorf("failed to enable IP forwarding with sysctl: %w", err)
 	}
-	f.v6Saved = nil
-	log.Info("IPv6 forwarding disabled")
+	f.enabledCounter = 1
+	log.Info("IP forwarding enabled")
+
+	return nil
+}
+
+func (f *IPForwardingState) ReleaseForwarding() error {
+	if f.enabledCounter == 0 {
+		return nil
+	}
+
+	if f.enabledCounter > 1 {
+		f.enabledCounter--
+		return nil
+	}
+
+	// if failed to disable IP forwarding we anyway decrement the counter
+	f.enabledCounter = 0
+
+	// todo call systemops.DisableIPForwarding()
 	return nil
 }

client/internal/routemanager/ipfwdstate/ipfwdstate_privileged_linux_test.go

@@ -1,39 +0,0 @@
-//go:build privileged
-
-package ipfwdstate
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	"github.com/stretchr/testify/require"
-)
-
-// TestRequestRoutingV6ToV4Transition verifies that a v4-only routing request
-// releases a previously held routing-owned v6 reference without touching
-// references held by DNAT rules.
-func TestRequestRoutingV6ToV4Transition(t *testing.T) {
-	f := NewIPForwardingState("wt-fwd-test")
-
-	require.NoError(t, f.RequestRouting(true), "request routing with v6")
-	v4, v6 := f.Counts()
-	assert.Equal(t, 1, v4, "v4 reference held")
-	assert.Equal(t, 1, v6, "v6 reference held")
-
-	require.NoError(t, f.RequestRouting(false), "request routing v4-only")
-	v4, v6 = f.Counts()
-	assert.Equal(t, 1, v4, "v4 reference kept")
-	assert.Equal(t, 0, v6, "routing-owned v6 reference released")
-
-	// A DNAT-held reference survives a v4-only routing request.
-	require.NoError(t, f.RequestForwarding(true), "dnat v6 reference")
-	require.NoError(t, f.RequestRouting(false), "repeat v4-only request")
-	_, v6 = f.Counts()
-	assert.Equal(t, 1, v6, "dnat-held v6 reference survives")
-	require.NoError(t, f.ReleaseForwarding(true), "release dnat v6 reference")
-
-	require.NoError(t, f.ReleaseRouting(), "release routing")
-	v4, v6 = f.Counts()
-	assert.Equal(t, 0, v4, "all v4 references released")
-	assert.Equal(t, 0, v6, "all v6 references released")
-}

client/internal/routemanager/sysctl/sysctl_linux.go

@@ -58,7 +58,11 @@ func Setup(wgIface iface) (map[string]int, error) {
 			continue
 		}
 
-		i := fmt.Sprintf(rpFilterInterfacePath, EscapeInterfaceName(intf.Name))
+		// Escape '%' and '.' so they survive the dot-to-slash conversion in Set()
+		safeName := strings.ReplaceAll(intf.Name, "%", percentEscape)
+		safeName = strings.ReplaceAll(safeName, ".", dotEscape)
+
+		i := fmt.Sprintf(rpFilterInterfacePath, safeName)
 		oldVal, err := Set(i, 2, true)
 		if err != nil {
 			result = multierror.Append(result, err)
@@ -70,13 +74,6 @@ func Setup(wgIface iface) (map[string]int, error) {
 	return keys, nberrors.FormatErrorOrNil(result)
 }
 
-// EscapeInterfaceName escapes '%' and '.' in an interface name (e.g. VLANs
-// like eth0.100) so the name survives the dot-to-slash conversion in Set.
-func EscapeInterfaceName(name string) string {
-	safe := strings.ReplaceAll(name, "%", percentEscape)
-	return strings.ReplaceAll(safe, ".", dotEscape)
-}
-
 // Set sets a sysctl configuration, if onlyIfOne is true it will only set the new value if it's set to 1
 func Set(key string, desiredValue int, onlyIfOne bool) (int, error) {
 	path := strings.ReplaceAll(key, ".", "/")

client/internal/routemanager/systemops/systemops_android.go

@@ -32,17 +32,8 @@ func (r *SysOps) removeFromRouteTable(netip.Prefix, Nexthop) error {
 	return nil
 }
 
-func EnableV4IPForwarding() error {
-	log.Infof("Enable IPv4 forwarding is not implemented on %s", runtime.GOOS)
-	return nil
-}
-
-func EnableV6IPForwarding(string) (map[string]int, error) {
-	log.Infof("Enable IPv6 forwarding is not implemented on %s", runtime.GOOS)
-	return map[string]int{}, nil
-}
-
-func DisableV6IPForwarding(map[string]int) error {
+func EnableIPForwarding() error {
+	log.Infof("Enable IP forwarding is not implemented on %s", runtime.GOOS)
 	return nil
 }
 

client/internal/routemanager/systemops/systemops_ios.go

@@ -58,17 +58,8 @@ func (r *SysOps) removeFromRouteTable(netip.Prefix, Nexthop) error {
 	return nil
 }
 
-func EnableV4IPForwarding() error {
-	log.Infof("Enable IPv4 forwarding is not implemented on %s", runtime.GOOS)
-	return nil
-}
-
-func EnableV6IPForwarding(string) (map[string]int, error) {
-	log.Infof("Enable IPv6 forwarding is not implemented on %s", runtime.GOOS)
-	return map[string]int{}, nil
-}
-
-func DisableV6IPForwarding(map[string]int) error {
+func EnableIPForwarding() error {
+	log.Infof("Enable IP forwarding is not implemented on %s", runtime.GOOS)
 	return nil
 }
 

client/internal/routemanager/systemops/systemops_linux.go

@@ -763,10 +763,13 @@ func flushRoutes(tableID, family int) error {
 	return nberrors.FormatErrorOrNil(result)
 }
 
-func EnableV4IPForwarding() error {
+func EnableIPForwarding() error {
 	if _, err := sysctl.Set(ipv4ForwardingPath, 1, false); err != nil {
 		return err
 	}
+	if _, err := sysctl.Set(ipv6ForwardingPath, 1, false); err != nil {
+		log.Warnf("failed to enable IPv6 forwarding: %v", err)
+	}
 	return nil
 }
 

client/internal/routemanager/systemops/systemops_nonlinux.go

@@ -43,17 +43,8 @@ func (r *SysOps) RemoveVPNRoute(prefix netip.Prefix, intf *net.Interface) error
 	return r.genericRemoveVPNRoute(prefix, intf)
 }
 
-func EnableV4IPForwarding() error {
-	log.Infof("Enable IPv4 forwarding is not implemented on %s", runtime.GOOS)
-	return nil
-}
-
-func EnableV6IPForwarding(string) (map[string]int, error) {
-	log.Infof("Enable IPv6 forwarding is not implemented on %s", runtime.GOOS)
-	return map[string]int{}, nil
-}
-
-func DisableV6IPForwarding(map[string]int) error {
+func EnableIPForwarding() error {
+	log.Infof("Enable IP forwarding is not implemented on %s", runtime.GOOS)
 	return nil
 }
 

client/internal/routemanager/systemops/v6forwarding_linux.go

@@ -1,92 +0,0 @@
-//go:build !android
-
-package systemops
-
-import (
-	"fmt"
-	"net"
-	"os"
-
-	"github.com/hashicorp/go-multierror"
-	log "github.com/sirupsen/logrus"
-
-	nberrors "github.com/netbirdio/netbird/client/errors"
-	"github.com/netbirdio/netbird/client/internal/routemanager/sysctl"
-)
-
-const (
-	// 1 (default) accepts RAs only while forwarding is off; 2 keeps RA
-	// acceptance on regardless, so RA-installed host defaults survive our
-	// v6 forwarding flip.
-	acceptRAInterfacePath  = "net.ipv6.conf.%s.accept_ra"
-	acceptRADefaultPath    = "net.ipv6.conf.default.accept_ra"
-	acceptRAProcPathFormat = "/proc/sys/net/ipv6/conf/%s/accept_ra"
-)
-
-// EnableV6IPForwarding bumps accept_ra=2 on host v6 interfaces before flipping
-// forwarding=1, so RA-installed host defaults survive. Returns the prior values
-// of sysctls we actually changed; entries already at the target are omitted.
-func EnableV6IPForwarding(wgIfaceName string) (map[string]int, error) {
-	saved := map[string]int{}
-	bumpAcceptRA(saved, wgIfaceName)
-
-	oldVal, err := sysctl.Set(ipv6ForwardingPath, 1, false)
-	if err != nil {
-		return saved, err
-	}
-	if oldVal != 1 {
-		saved[ipv6ForwardingPath] = oldVal
-	}
-	return saved, nil
-}
-
-// DisableV6IPForwarding restores what EnableV6IPForwarding captured.
-func DisableV6IPForwarding(saved map[string]int) error {
-	var result *multierror.Error
-	for key, value := range saved {
-		if _, err := sysctl.Set(key, value, false); err != nil {
-			result = multierror.Append(result, fmt.Errorf("restore %s: %w", key, err))
-		}
-	}
-	return nberrors.FormatErrorOrNil(result)
-}
-
-func bumpAcceptRA(saved map[string]int, wgIfaceName string) {
-	// Also bump conf.default so interfaces created while forwarding is on
-	// (hotplug, new Wi-Fi/dock) inherit accept_ra=2 and keep accepting RAs.
-	bumpAcceptRAKey(saved, acceptRADefaultPath)
-
-	interfaces, err := net.Interfaces()
-	if err != nil {
-		log.Warnf("list interfaces for accept_ra: %v", err)
-		return
-	}
-	for _, intf := range interfaces {
-		if intf.Name == "lo" || intf.Name == wgIfaceName {
-			continue
-		}
-		bumpAcceptRAForInterface(saved, intf.Name)
-	}
-}
-
-func bumpAcceptRAForInterface(saved map[string]int, name string) {
-	// Build procfs path from name, not the dotted key: VLAN names like eth0.100.
-	if _, err := os.Stat(fmt.Sprintf(acceptRAProcPathFormat, name)); err != nil {
-		return
-	}
-	bumpAcceptRAKey(saved, fmt.Sprintf(acceptRAInterfacePath, sysctl.EscapeInterfaceName(name)))
-}
-
-func bumpAcceptRAKey(saved map[string]int, key string) {
-	// onlyIfOne=true: leave admin overrides (0, 2) alone.
-	oldVal, err := sysctl.Set(key, 2, true)
-	if err != nil {
-		log.Warnf("bump %s: %v", key, err)
-		return
-	}
-	// With onlyIfOne, a write only happened when the old value was 1; values
-	// left untouched (0, 2) must not be recorded for restore.
-	if oldVal == 1 {
-		saved[key] = oldVal
-	}
-}

client/proto/daemon.pb.go

@@ -5628,13 +5628,9 @@ func (x *GetPeerSSHHostKeyResponse) GetFound() bool {
 type RequestJWTAuthRequest struct {
 	state protoimpl.MessageState `protogen:"open.v1"`
 	// hint for OIDC login_hint parameter (typically email address)
-	Hint *string `protobuf:"bytes,1,opt,name=hint,proto3,oneof" json:"hint,omitempty"`
-	// hasGraphicalSession tells the daemon that the caller has a graphical session,
-	// which decides whether PKCE or the device code flow is preferred. The daemon
-	// cannot detect this itself: it does not inherit the session environment.
-	HasGraphicalSession bool `protobuf:"varint,2,opt,name=hasGraphicalSession,proto3" json:"hasGraphicalSession,omitempty"`
-	unknownFields       protoimpl.UnknownFields
-	sizeCache           protoimpl.SizeCache
+	Hint          *string `protobuf:"bytes,1,opt,name=hint,proto3,oneof" json:"hint,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
 }
 
 func (x *RequestJWTAuthRequest) Reset() {
@@ -5674,13 +5670,6 @@ func (x *RequestJWTAuthRequest) GetHint() string {
 	return ""
 }
 
-func (x *RequestJWTAuthRequest) GetHasGraphicalSession() bool {
-	if x != nil {
-		return x.HasGraphicalSession
-	}
-	return false
-}
-
 // RequestJWTAuthResponse contains authentication flow information
 type RequestJWTAuthResponse struct {
 	state protoimpl.MessageState `protogen:"open.v1"`
@@ -5905,13 +5894,9 @@ type RequestExtendAuthSessionRequest struct {
 	state protoimpl.MessageState `protogen:"open.v1"`
 	// Optional OIDC login_hint (typically the user's email) to pre-fill the
 	// IdP login form.
-	Hint *string `protobuf:"bytes,1,opt,name=hint,proto3,oneof" json:"hint,omitempty"`
-	// hasGraphicalSession tells the daemon that the caller has a graphical session,
-	// which decides whether PKCE or the device code flow is preferred. The daemon
-	// cannot detect this itself: it does not inherit the session environment.
-	HasGraphicalSession bool `protobuf:"varint,2,opt,name=hasGraphicalSession,proto3" json:"hasGraphicalSession,omitempty"`
-	unknownFields       protoimpl.UnknownFields
-	sizeCache           protoimpl.SizeCache
+	Hint          *string `protobuf:"bytes,1,opt,name=hint,proto3,oneof" json:"hint,omitempty"`
+	unknownFields protoimpl.UnknownFields
+	sizeCache     protoimpl.SizeCache
 }
 
 func (x *RequestExtendAuthSessionRequest) Reset() {
@@ -5951,13 +5936,6 @@ func (x *RequestExtendAuthSessionRequest) GetHint() string {
 	return ""
 }
 
-func (x *RequestExtendAuthSessionRequest) GetHasGraphicalSession() bool {
-	if x != nil {
-		return x.HasGraphicalSession
-	}
-	return false
-}
-
 // RequestExtendAuthSessionResponse carries the verification URI the UI
 // should open in a browser. The daemon retains the flow state and resolves
 // it via WaitExtendAuthSession.
@@ -7525,10 +7503,9 @@ const file_daemon_proto_rawDesc = "" +
 	"sshHostKey\x12\x16\n" +
 	"\x06peerIP\x18\x02 \x01(\tR\x06peerIP\x12\x1a\n" +
 	"\bpeerFQDN\x18\x03 \x01(\tR\bpeerFQDN\x12\x14\n" +
-	"\x05found\x18\x04 \x01(\bR\x05found\"k\n" +
+	"\x05found\x18\x04 \x01(\bR\x05found\"9\n" +
 	"\x15RequestJWTAuthRequest\x12\x17\n" +
-	"\x04hint\x18\x01 \x01(\tH\x00R\x04hint\x88\x01\x01\x120\n" +
-	"\x13hasGraphicalSession\x18\x02 \x01(\bR\x13hasGraphicalSessionB\a\n" +
+	"\x04hint\x18\x01 \x01(\tH\x00R\x04hint\x88\x01\x01B\a\n" +
 	"\x05_hint\"\x9a\x02\n" +
 	"\x16RequestJWTAuthResponse\x12(\n" +
 	"\x0fverificationURI\x18\x01 \x01(\tR\x0fverificationURI\x128\n" +
@@ -7548,10 +7525,9 @@ const file_daemon_proto_rawDesc = "" +
 	"\x14WaitJWTTokenResponse\x12\x14\n" +
 	"\x05token\x18\x01 \x01(\tR\x05token\x12\x1c\n" +
 	"\ttokenType\x18\x02 \x01(\tR\ttokenType\x12\x1c\n" +
-	"\texpiresIn\x18\x03 \x01(\x03R\texpiresIn\"u\n" +
+	"\texpiresIn\x18\x03 \x01(\x03R\texpiresIn\"C\n" +
 	"\x1fRequestExtendAuthSessionRequest\x12\x17\n" +
-	"\x04hint\x18\x01 \x01(\tH\x00R\x04hint\x88\x01\x01\x120\n" +
-	"\x13hasGraphicalSession\x18\x02 \x01(\bR\x13hasGraphicalSessionB\a\n" +
+	"\x04hint\x18\x01 \x01(\tH\x00R\x04hint\x88\x01\x01B\a\n" +
 	"\x05_hint\"\xe0\x01\n" +
 	" RequestExtendAuthSessionResponse\x12(\n" +
 	"\x0fverificationURI\x18\x01 \x01(\tR\x0fverificationURI\x128\n" +

client/proto/daemon.proto

@@ -894,10 +894,6 @@ message GetPeerSSHHostKeyResponse {
 message RequestJWTAuthRequest {
   // hint for OIDC login_hint parameter (typically email address)
   optional string hint = 1;
-  // hasGraphicalSession tells the daemon that the caller has a graphical session,
-  // which decides whether PKCE or the device code flow is preferred. The daemon
-  // cannot detect this itself: it does not inherit the session environment.
-  bool hasGraphicalSession = 2;
 }
 
 // RequestJWTAuthResponse contains authentication flow information
@@ -941,10 +937,6 @@ message RequestExtendAuthSessionRequest {
   // Optional OIDC login_hint (typically the user's email) to pre-fill the
   // IdP login form.
   optional string hint = 1;
-  // hasGraphicalSession tells the daemon that the caller has a graphical session,
-  // which decides whether PKCE or the device code flow is preferred. The daemon
-  // cannot detect this itself: it does not inherit the session environment.
-  bool hasGraphicalSession = 2;
 }
 
 // RequestExtendAuthSessionResponse carries the verification URI the UI

client/server/server.go

@@ -682,11 +682,6 @@ func (s *Server) Login(callerCtx context.Context, msg *proto.LoginRequest) (*pro
 		oAuthFlow, err := auth.NewOAuthFlow(ctx, config, msg.IsUnixDesktopClient, false, hint)
 		if err != nil {
 			state.Set(internal.StatusLoginFailed)
-			// enrolling a device is the one flow a setup key can replace
-			if auth.IsSSOUnavailable(err) {
-				return nil, fmt.Errorf("%w. Set this device up with a setup key instead: "+
-					"https://docs.netbird.io/how-to/register-machines-using-setup-keys", err)
-			}
 			return nil, err
 		}
 
@@ -1728,8 +1723,8 @@ func (s *Server) RequestJWTAuth(
 		hint = profilemanager.GetLoginHint()
 	}
 
-	// the daemon has no graphical session of its own, only the caller can answer this
-	oAuthFlow, err := auth.NewOAuthFlow(ctx, config, msg.GetHasGraphicalSession(), false, hint)
+	isDesktop := isUnixRunningDesktop()
+	oAuthFlow, err := auth.NewOAuthFlow(ctx, config, isDesktop, false, hint)
 	if err != nil {
 		return nil, gstatus.Errorf(codes.Internal, "failed to create OAuth flow: %v", err)
 	}
@@ -1832,8 +1827,8 @@ func (s *Server) RequestExtendAuthSession(
 		hint = profilemanager.GetLoginHint()
 	}
 
-	// the daemon has no graphical session of its own, only the caller can answer this
-	oAuthFlow, err := auth.NewOAuthFlow(ctx, config, msg.GetHasGraphicalSession(), false, hint)
+	isDesktop := isUnixRunningDesktop()
+	oAuthFlow, err := auth.NewOAuthFlow(ctx, config, isDesktop, false, hint)
 	if err != nil {
 		return nil, gstatus.Errorf(codes.Internal, "failed to create OAuth flow: %v", err)
 	}
@@ -2005,6 +2000,13 @@ func (s *Server) ExposeService(req *proto.ExposeServiceRequest, srv proto.Daemon
 	return nil
 }
 
+func isUnixRunningDesktop() bool {
+	if runtime.GOOS != "linux" && runtime.GOOS != "freebsd" {
+		return false
+	}
+	return os.Getenv("DESKTOP_SESSION") != "" || os.Getenv("XDG_CURRENT_DESKTOP") != ""
+}
+
 func (s *Server) runProbes(ctx context.Context, waitForProbeResult bool) {
 	if s.connectClient == nil {
 		return

client/ssh/common.go

@@ -13,7 +13,6 @@ import (
 	"golang.org/x/crypto/ssh"
 
 	"github.com/netbirdio/netbird/client/proto"
-	"github.com/netbirdio/netbird/util"
 )
 
 const (
@@ -93,8 +92,7 @@ func printAuthInstructions(stderr io.Writer, authResponse *proto.RequestJWTAuthR
 
 // RequestJWTToken requests or retrieves a JWT token for SSH authentication
 func RequestJWTToken(ctx context.Context, client proto.DaemonServiceClient, stdout, stderr io.Writer, useCache bool, hint string, openBrowser func(string) error) (string, error) {
-	// the ssh client runs in the user's session, the daemon does not: tell it what we can see
-	req := &proto.RequestJWTAuthRequest{HasGraphicalSession: util.HasGraphicalSession()}
+	req := &proto.RequestJWTAuthRequest{}
 	if hint != "" {
 		req.Hint = &hint
 	}
@@ -195,3 +193,4 @@ func buildAddressList(hostname string, remote net.Addr) []string {
 	}
 	return addresses
 }
+

client/ui/authsession/service.go

@@ -58,8 +58,7 @@ func (s *Session) RequestExtend(ctx context.Context, p ExtendStartParams) (Exten
 		return ExtendStartResult{}, err
 	}
 
-	// a request from the UI implies a graphical session, which the daemon cannot detect itself
-	req := &proto.RequestExtendAuthSessionRequest{HasGraphicalSession: true}
+	req := &proto.RequestExtendAuthSessionRequest{}
 	if p.Hint != "" {
 		h := p.Hint
 		req.Hint = &h

client/ui/services/connection.go

@@ -108,11 +108,10 @@ func (s *Connection) Login(ctx context.Context, p LoginParams) (LoginResult, err
 	}
 
 	req := &proto.LoginRequest{
-		ManagementUrl: p.ManagementURL,
-		SetupKey:      p.SetupKey,
-		Hostname:      p.Hostname,
-		// a login driven by the UI always has a graphical session available
-		IsUnixDesktopClient: true,
+		ManagementUrl:       p.ManagementURL,
+		SetupKey:            p.SetupKey,
+		Hostname:            p.Hostname,
+		IsUnixDesktopClient: runtime.GOOS == "linux",
 	}
 	if profileName != "" {
 		req.ProfileName = ptrStr(profileName)

util/common.go

@@ -3,7 +3,6 @@ package util
 import (
 	"os"
 	"os/exec"
-	"runtime"
 
 	"github.com/skratchdot/open-golang/open"
 )
@@ -16,39 +15,6 @@ func OpenBrowser(url string) error {
 	return open.Run(url)
 }
 
-// browserSessionEnvVars returns the variables that decide whether OpenBrowser can open a URL:
-// BROWSER is the explicit override it honors first, DESKTOP_SESSION and XDG_CURRENT_DESKTOP are
-// what xdg-open uses to pick a handler, and DISPLAY / WAYLAND_DISPLAY are what any graphical
-// browser it launches needs.
-func browserSessionEnvVars() []string {
-	return []string{"BROWSER", "DESKTOP_SESSION", "XDG_CURRENT_DESKTOP", "DISPLAY", "WAYLAND_DISPLAY"}
-}
-
-// HasGraphicalSession reports whether this process can open a browser and serve a loopback
-// redirect back to it. Windows and macOS always can. On Linux and FreeBSD the answer is env
-// based, so it only holds for a process started from the graphical session itself: a service
-// does not inherit those variables and always reports false, which is why callers running in
-// the user's session pass their own answer to the daemon.
-func HasGraphicalSession() bool {
-	if runtime.GOOS != "linux" && runtime.GOOS != "freebsd" {
-		return true
-	}
-
-	for _, env := range browserSessionEnvVars() {
-		if os.Getenv(env) != "" {
-			return true
-		}
-	}
-
-	// tty and unspecified sessions have no display; anything else (x11, wayland, mir) does
-	switch os.Getenv("XDG_SESSION_TYPE") {
-	case "", "tty", "unspecified":
-		return false
-	default:
-		return true
-	}
-}
-
 // SliceDiff returns the elements in slice `x` that are not in slice `y`
 func SliceDiff(x, y []string) []string {
 	mapY := make(map[string]struct{}, len(y))

util/session_test.go

@@ -1,47 +0,0 @@
-package util
-
-import (
-	"os"
-	"runtime"
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-)
-
-func TestHasGraphicalSession(t *testing.T) {
-	if runtime.GOOS != "linux" && runtime.GOOS != "freebsd" {
-		assert.True(t, HasGraphicalSession(), "%s always has a graphical session", runtime.GOOS)
-		return
-	}
-
-	// clear anything inherited from the session running the test, restored on cleanup
-	for _, env := range append(browserSessionEnvVars(), "XDG_SESSION_TYPE") {
-		t.Setenv(env, "")
-		os.Unsetenv(env)
-	}
-
-	assert.False(t, HasGraphicalSession(), "no session variables means no graphical session")
-
-	tests := []struct {
-		env      string
-		value    string
-		expected bool
-	}{
-		{env: "DISPLAY", value: ":0", expected: true},
-		{env: "WAYLAND_DISPLAY", value: "wayland-0", expected: true},
-		{env: "DESKTOP_SESSION", value: "gnome", expected: true},
-		{env: "XDG_CURRENT_DESKTOP", value: "KDE", expected: true},
-		{env: "BROWSER", value: "firefox", expected: true},
-		{env: "XDG_SESSION_TYPE", value: "wayland", expected: true},
-		{env: "XDG_SESSION_TYPE", value: "x11", expected: true},
-		{env: "XDG_SESSION_TYPE", value: "tty", expected: false},
-		{env: "XDG_SESSION_TYPE", value: "unspecified", expected: false},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.env+"="+tt.value, func(t *testing.T) {
-			t.Setenv(tt.env, tt.value)
-			assert.Equal(t, tt.expected, HasGraphicalSession(), "%s=%s", tt.env, tt.value)
-		})
-	}
-}