Removes static vars

client/mdm/policy.go

@@ -84,16 +84,48 @@ func NewPolicy(values map[string]any) *Policy {
 	return &Policy{values: values}
 }
 
-// LoadPolicy reads the platform-native MDM configuration. Returns an
-// empty (but non-nil) Policy when no source is present, the source is
-// empty, or the platform is unsupported.
+// PolicyFetcher is implemented by mobile platforms (Android / iOS) that
+// push the OS-managed configuration into the Go runtime instead of
+// having Go read an on-disk source directly. Desktop platforms ignore
+// this interface — Loader.loadPlatform on windows/darwin reads the
+// registry / plist on its own. A Loader constructed with a non-nil
+// fetcher delegates to it on mobile; passing nil disables MDM
+// enforcement (loadPlatform returns nil values).
+type PolicyFetcher interface {
+	Fetch() map[string]any
+}
+
+// Loader is the DI-friendly entry point for reading the active MDM
+// policy. Construct one at the daemon's lifecycle owner (Server on
+// desktop, gomobile-exposed bridge on mobile) and pass it to anything
+// that needs to read MDM state (the reload ticker, profilemanager's
+// Config). Each callsite has the Loader handed in instead of looking
+// up package-level state.
+type Loader struct {
+	fetcher PolicyFetcher
+}
+
+// NewLoader constructs a Loader. The fetcher is consulted only on
+// mobile builds (ios || android); on desktop it is unused but accepted
+// to keep a single constructor signature across platforms — pass nil
+// on desktop.
+func NewLoader(f PolicyFetcher) *Loader {
+	return &Loader{fetcher: f}
+}
+
+// Load reads the platform-native MDM configuration and returns a
+// Policy. Returns an empty (but non-nil) Policy when no source is
+// present, the source is empty, or the platform is unsupported.
 //
 // Diagnostic logging differentiates the three states:
 //   - source absent / unsupported platform: trace log only
 //   - source present, zero keys:             info "MDM enrolled (no managed keys)"
 //   - source present, N keys:                info "MDM enrolled with N managed keys: [...]"
-func LoadPolicy() *Policy {
-	values, err := loadPlatformPolicy()
+func (l *Loader) Load() *Policy {
+	if l == nil {
+		return &Policy{values: map[string]any{}}
+	}
+	values, err := l.loadPlatform()
 	if err != nil {
 		log.Tracef("MDM policy load: %v", err)
 		return &Policy{values: map[string]any{}}

client/mdm/policy_darwin.go

@@ -25,8 +25,10 @@ import (
 // writable plist, as a defense against tampered installs.
 const policyPlistPath = "/Library/Managed Preferences/io.netbird.client.plist"
 
-// loadPlatformPolicy reads the MDM-managed configuration from the macOS
-// managed-preferences plist at policyPlistPath. Returns:
+// loadPlatform reads the MDM-managed configuration from the macOS
+// managed-preferences plist at policyPlistPath. The Loader's fetcher
+// field is unused on this platform — the plist is the authoritative
+// source. Returns:
 //   - (nil, nil)  when the plist is absent (device not MDM-enrolled for
 //     NetBird, or admin has not yet pushed a payload)
 //   - (map, nil)  with N entries when N managed values are present
@@ -39,7 +41,13 @@ const policyPlistPath = "/Library/Managed Preferences/io.netbird.client.plist"
 // skipped so a stray entry in the payload does not block startup.
 // Native plist value types map naturally onto the Policy accessor
 // expectations (GetString / GetBool / GetInt / GetStringSlice).
-func loadPlatformPolicy() (map[string]any, error) {
+func (l *Loader) loadPlatform() (map[string]any, error) {
+	// Honour the injected fetcher when present so tests (and any
+	// future non-macOS MDM channel) can short-circuit the plist read
+	// with a scripted policy.
+	if l != nil && l.fetcher != nil {
+		return l.fetcher.Fetch(), nil
+	}
 	f, err := os.Open(policyPlistPath)
 	if err != nil {
 		if errors.Is(err, fs.ErrNotExist) {

client/mdm/policy_mobile.go

@@ -2,41 +2,14 @@
 
 package mdm
 
-// PolicyFetcher is the bridge between Go and the mobile native layer
-// (Kotlin/Java on Android, Swift on iOS). The native layer registers
-// an implementation at gomobile init via SetMobilePolicyFetcher;
-// thereafter every call to loadPlatformPolicy delegates to the
-// registered fetcher, which reads the OS-native managed-config store
-// (RestrictionsManager on Android, com.apple.configuration.managed
-// UserDefaults on iOS) and returns the current snapshot.
-//
-// Set-once at init, never mutated at runtime → no synchronisation
-// required for the read path. The native layer must register before
-// any Go code starts polling or processing MDM events.
-type PolicyFetcher interface {
-	Fetch() map[string]any
-}
-
-var fetcher PolicyFetcher
-
-// SetMobilePolicyFetcher registers the native-provided fetcher. Call
-// exactly once from the gomobile init code (Kotlin Application.onCreate
-// / Swift AppDelegate) before the daemon starts. Passing nil disables
-// MDM enforcement on this build (loadPlatformPolicy returns
-// (nil, nil) — the platform-absent sentinel that LoadPolicy treats as
-// "no MDM source present").
-func SetMobilePolicyFetcher(p PolicyFetcher) {
-	fetcher = p
-}
-
-// loadPlatformPolicy delegates to the native-provided fetcher. Returns
-// (nil, nil) — the platform-absent sentinel — when no fetcher has been
-// registered yet, so the package behaves identically to a desktop
-// device without an MDM source.
-func loadPlatformPolicy() (map[string]any, error) {
-	if fetcher == nil {
-		//nolint:nilnil // (nil, nil) is the documented platform-absent sentinel; see LoadPolicy.
+// loadPlatform reads the OS-managed configuration via the native
+// PolicyFetcher injected at Loader construction. Returns
+// (nil, nil) — the platform-absent sentinel that Loader.Load treats as
+// "no MDM source present" — when no fetcher was provided.
+func (l *Loader) loadPlatform() (map[string]any, error) {
+	if l == nil || l.fetcher == nil {
+		//nolint:nilnil // (nil, nil) is the documented platform-absent sentinel; see Loader.Load.
 		return nil, nil
 	}
-	return fetcher.Fetch(), nil
+	return l.fetcher.Fetch(), nil
 }

client/mdm/policy_other.go

@@ -2,13 +2,17 @@
 
 package mdm
 
-// loadPlatformPolicy returns no policy on platforms without an MDM channel
-// (Linux, FreeBSD). MDM enforcement is off and the client behaves as if
-// the feature did not exist. Returns (nil, nil) — the platform-absent
-// sentinel the caller (LoadPolicy in policy.go) treats as "no MDM
-// source present"; an error here would just translate to the same
-// outcome with an extra log line.
-func loadPlatformPolicy() (map[string]any, error) {
-	//nolint:nilnil // (nil, nil) is the documented platform-absent sentinel; see LoadPolicy.
+// loadPlatform reads the MDM policy on platforms without a native MDM
+// channel (Linux, FreeBSD). When no fetcher was injected the policy is
+// (nil, nil) — the platform-absent sentinel that Loader.Load treats as
+// "MDM enforcement disabled". A non-nil fetcher takes precedence: it
+// is the test-seam used by unit tests to inject a scripted policy
+// without touching the OS, and the same hook supports any future
+// non-mobile OS that grows an out-of-band MDM channel.
+func (l *Loader) loadPlatform() (map[string]any, error) {
+	if l != nil && l.fetcher != nil {
+		return l.fetcher.Fetch(), nil
+	}
+	//nolint:nilnil // (nil, nil) is the documented platform-absent sentinel; see Loader.Load.
 	return nil, nil
 }

client/mdm/policy_test.go

@@ -150,10 +150,12 @@ func TestPolicy_GetStringSlice(t *testing.T) {
 	})
 }
 
-func TestLoadPolicy_PlatformStubReturnsEmpty(t *testing.T) {
-	// loadPlatformPolicy is a stub on every OS for Phase 1. LoadPolicy must
-	// degrade gracefully and never return nil.
-	p := LoadPolicy()
+func TestLoader_NilFetcherReturnsEmpty(t *testing.T) {
+	// Loader.Load with no fetcher (desktop construction) must degrade
+	// gracefully and never return nil; on linux loadPlatform is a stub
+	// returning (nil, nil), and Load is expected to translate that
+	// into a non-nil empty Policy.
+	p := NewLoader(nil).Load()
 	require.NotNil(t, p)
 	assert.True(t, p.IsEmpty())
 	assert.Empty(t, p.ManagedKeys())

client/mdm/policy_windows.go

@@ -61,8 +61,10 @@ func readRegistryValue(k registry.Key, name, canonical string, out map[string]an
 	}
 }
 
-// loadPlatformPolicy reads the MDM-managed configuration from the
-// Windows registry under HKLM\Software\Policies\NetBird. Returns:
+// loadPlatform reads the MDM-managed configuration from the Windows
+// registry under HKLM\Software\Policies\NetBird. The Loader's fetcher
+// field is unused on this platform — the registry is the
+// authoritative source. Returns:
 //   - (nil, nil)  when the key is absent (device not MDM-enrolled for NetBird)
 //   - (map, nil)  with N entries when N managed values are set (N may be 0)
 //   - (nil, err)  on open / enumerate registry errors
@@ -70,7 +72,13 @@ func readRegistryValue(k registry.Key, name, canonical string, out map[string]an
 // Per-value type coercion + skip-on-error is delegated to
 // readRegistryValue. Unknown value names are logged and skipped so a
 // malformed deployment does not block startup.
-func loadPlatformPolicy() (map[string]any, error) {
+func (l *Loader) loadPlatform() (map[string]any, error) {
+	// Honour the injected fetcher when present so tests (and any
+	// future non-Windows MDM channel) can short-circuit the registry
+	// read with a scripted policy.
+	if l != nil && l.fetcher != nil {
+		return l.fetcher.Fetch(), nil
+	}
 	k, err := registry.OpenKey(registry.LOCAL_MACHINE, policyRegistryPath, registry.QUERY_VALUE)
 	if err != nil {
 		if errors.Is(err, registry.ErrNotExist) {

client/mdm/ticker.go

@@ -15,33 +15,33 @@ import (
 // instead, hence anticipating the ticker mechanism entirely.
 const DefaultReloadInterval = 1 * time.Minute
 
-// policyLoader is the indirection through which the ticker reads the
-// OS-native policy, both for the initial observation and on every tick.
-// Production points it at LoadPolicy; tests in this package override it to
-// feed a scripted sequence of policies without touching the real OS store.
-var policyLoader = LoadPolicy
-
-// Ticker periodically re-reads the OS-native MDM policy via LoadPolicy and
-// invokes the onChange callback (supplied to Run) whenever the observed
-// Policy diverges from the last observation (added / removed / changed
-// keys). Launch with Run from a goroutine; cancel the supplied context
-// to stop.
+// Ticker periodically re-reads the OS-native MDM policy via the
+// injected Loader and invokes the onChange callback (supplied to Run)
+// whenever the observed Policy diverges from the last observation
+// (added / removed / changed keys). Launch with Run from a goroutine;
+// cancel the supplied context to stop.
 type Ticker struct {
 	interval time.Duration
+	loader   *Loader
 	prev     *Policy
 }
 
 // NewTicker constructs a Ticker that will re-read the OS-native policy
-// every reloadInterval once Run is called.
-// The initial snapshot is populated by calling policyLoader at
+// every reloadInterval once Run is called. The Loader is injected so
+// the ticker doesn't depend on any package-level state — production
+// passes the daemon-owned Loader, tests pass a fake Loader (built with
+// a fake PolicyFetcher).
+//
+// The initial snapshot is populated by calling loader.Load() at
 // construction time so the first tick only fires
 // onChange when the policy actually changed since boot — without
 // this baseline the first tick would report every currently-managed
 // key as "added" and trigger a spurious engine restart.
-func NewTicker(reloadInterval time.Duration) *Ticker {
+func NewTicker(reloadInterval time.Duration, loader *Loader) *Ticker {
 	return &Ticker{
 		interval: reloadInterval,
-		prev:     policyLoader(),
+		loader:   loader,
+		prev:     loader.Load(),
 	}
 }
 
@@ -58,7 +58,7 @@ func (t *Ticker) Run(ctx context.Context, onChange func(prev, curr *Policy) erro
 			log.Info("MDM policy reload ticker stopped")
 			return
 		case <-tk.C:
-			curr := policyLoader()
+			curr := t.loader.Load()
 			if policiesEqual(t.prev, curr) {
 				continue
 			}

client/mdm/ticker_test.go

@@ -13,28 +13,40 @@ import (
 // testReloadInterval for speeding up the ticker cadence under `go test`
 const testReloadInterval = 1 * time.Second
 
-// withPolicyLoader overrides the package-level policyLoader for the duration
-// of the test so the ticker observes a scripted policy instead of the real
-// OS-native store. The original loader is restored on cleanup.
-func withPolicyLoader(t *testing.T, fn func() *Policy) {
-	t.Helper()
-	prev := policyLoader
-	policyLoader = fn
-	t.Cleanup(func() { policyLoader = prev })
+// fakePolicyFetcher implements PolicyFetcher returning a scripted
+// policy map. Goroutine-safe so the test can mutate the script while
+// the ticker is observing it.
+type fakePolicyFetcher struct {
+	mu     sync.Mutex
+	values map[string]any
+}
+
+func (f *fakePolicyFetcher) Fetch() map[string]any {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.values == nil {
+		return nil
+	}
+	out := make(map[string]any, len(f.values))
+	for k, v := range f.values {
+		out[k] = v
+	}
+	return out
+}
+
+func (f *fakePolicyFetcher) set(values map[string]any) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.values = values
 }
 
 func TestTicker_FiresOnChangeWithDelta(t *testing.T) {
-	var mu sync.Mutex
-	current := NewPolicy(nil) // initial observation: empty (no enforcement)
-	withPolicyLoader(t, func() *Policy {
-		mu.Lock()
-		defer mu.Unlock()
-		return current
-	})
+	fetcher := &fakePolicyFetcher{} // initial observation: empty (no enforcement)
+	loader := NewLoader(fetcher)
 
 	type change struct{ prev, curr *Policy }
 	changes := make(chan change, 1)
-	tk := NewTicker(testReloadInterval)
+	tk := NewTicker(testReloadInterval, loader)
 	require.Equal(t, testReloadInterval, tk.interval)
 
 	ctx, cancel := context.WithCancel(context.Background())
@@ -49,15 +61,13 @@ func TestTicker_FiresOnChangeWithDelta(t *testing.T) {
 		})
 		close(done)
 	}()
-	// Stop Run and wait for it to exit before returning, so the policyLoader
-	// restore in t.Cleanup can't race the ticker goroutine still reading it.
+	// Stop Run and wait for it to exit before returning, so the test
+	// goroutine doesn't race the still-running ticker.
 	defer func() { cancel(); <-done }()
 
-	// Flip the OS-observed policy from empty to one managed key. The next
-	// tick must detect the diff and invoke onChange.
-	mu.Lock()
-	current = NewPolicy(map[string]any{KeyManagementURL: "https://mdm.example.com:443"})
-	mu.Unlock()
+	// Flip the OS-observed policy from empty to one managed key. The
+	// next tick must detect the diff and invoke onChange.
+	fetcher.set(map[string]any{KeyManagementURL: "https://mdm.example.com:443"})
 
 	select {
 	case c := <-changes:
@@ -69,12 +79,11 @@ func TestTicker_FiresOnChangeWithDelta(t *testing.T) {
 }
 
 func TestTicker_NoCallbackWhenPolicyUnchanged(t *testing.T) {
-	withPolicyLoader(t, func() *Policy {
-		return NewPolicy(map[string]any{KeyBlockInbound: true})
-	})
+	fetcher := &fakePolicyFetcher{values: map[string]any{KeyBlockInbound: true}}
+	loader := NewLoader(fetcher)
 
 	fired := make(chan struct{}, 1)
-	tk := NewTicker(testReloadInterval)
+	tk := NewTicker(testReloadInterval, loader)
 
 	ctx, cancel := context.WithCancel(context.Background())
 	done := make(chan struct{})
@@ -90,8 +99,8 @@ func TestTicker_NoCallbackWhenPolicyUnchanged(t *testing.T) {
 	}()
 	defer func() { cancel(); <-done }()
 
-	// Over ~2 ticks at the 1s test cadence the policy never changes, so the
-	// diff guard must suppress the callback entirely.
+	// Over ~2 ticks at the 1s test cadence the policy never changes,
+	// so the diff guard must suppress the callback entirely.
 	select {
 	case <-fired:
 		t.Fatal("onChange fired despite an unchanged policy")