Implement Android TOTP and confirmed HOTP presentation (#107)

android/app/src/androidTest/kotlin/de/rfc1437/ironstorage/AdaptiveShellTest.kt

@@ -74,7 +74,7 @@ class AdaptiveShellTest {
                 original.search,
                 original.authentication,
                 original.editor,
-                original.settings,
+                original.settings, original.totp,
                 saved
             )
         compose.activity.runOnUiThread {
@@ -159,7 +159,7 @@ class AdaptiveShellTest {
                 original.search,
                 original.authentication,
                 original.editor,
-                original.settings,
+                original.settings, original.totp,
                 SavedStateHandle(
                     saved.keys().associateWith {
                         saved.get<Any>(it)
@@ -199,7 +199,7 @@ class AdaptiveShellTest {
             original.search,
             original.authentication,
             original.editor,
-            original.settings,
+            original.settings, original.totp,
             saved
         )
         compose.activity.runOnUiThread {
@@ -242,7 +242,7 @@ class AdaptiveShellTest {
             original.search,
             original.authentication,
             original.editor,
-            original.settings,
+            original.settings, original.totp,
             SavedStateHandle(mapOf("shell.tab" to "Passwords"))
         )
         compose.activity.runOnUiThread {

android/app/src/androidTest/kotlin/de/rfc1437/ironstorage/EntryViewerTest.kt

@@ -35,11 +35,12 @@ import de.rfc1437.ironstorage.core.PasswordField
 import de.rfc1437.ironstorage.core.PasswordKind
 import de.rfc1437.ironstorage.core.PasswordMutation
 import de.rfc1437.ironstorage.core.PasswordMutationPlan
+import de.rfc1437.ironstorage.core.PasswordOtp
+import de.rfc1437.ironstorage.core.PasswordOtpKind
 import de.rfc1437.ironstorage.core.PasswordRepository
 import de.rfc1437.ironstorage.core.PasswordRow
 import de.rfc1437.ironstorage.core.PasswordSection
 import de.rfc1437.ironstorage.core.PasswordState
-import de.rfc1437.ironstorage.core.PasswordTotp
 import de.rfc1437.ironstorage.core.ShellIcon
 import de.rfc1437.ironstorage.features.PasswordScreen
 import de.rfc1437.ironstorage.platform.AndroidSecretClipboard
@@ -70,7 +71,7 @@ class EntryViewerTest {
         compose.onNodeWithText("654321").assertDoesNotExist()
         compose.onNodeWithText("Unlock").performClick()
         compose.onNodeWithText("alice 日本語").performScrollTo().assertIsDisplayed()
-        compose.onNodeWithText("123456").performScrollTo().assertIsDisplayed()
+        compose.onNodeWithText("123 456").performScrollTo().assertIsDisplayed()
         compose.onNodeWithContentDescription("Reveal PIN").performScrollTo()
             .performSemanticsAction(SemanticsActions.OnClick) { org.junit.Assert.assertTrue(it()) }
         assertEquals(2uL, repository.lastId)
@@ -97,7 +98,7 @@ class EntryViewerTest {
         }
         compose.runOnIdle { repository.lease.value = AuthenticationState() }
         compose.onNode(hasSetTextAction()).assertDoesNotExist()
-        compose.onNodeWithText("123456").assertDoesNotExist()
+        compose.onNodeWithText("123 456").assertDoesNotExist()
         compose.onNodeWithText("First line\nSecond line 🌻").assertDoesNotExist()
         compose.onNodeWithText("Unlock").assertIsDisplayed()
     }
@@ -174,7 +175,7 @@ class EntryViewerTest {
             org.junit.Assert.assertTrue(android.os.SystemClock.elapsedRealtime() - started < 600000)
         }
     }
-    private class Fixture : PasswordRepository {
+    internal class Fixture : PasswordRepository {
         private val row =
             PasswordRow(
                 "row",
@@ -275,12 +276,18 @@ class EntryViewerTest {
         override fun unlock(passphrase: String) {
             lease.value = AuthenticationState(unlocked = true)
             state.value =
-                state.value.copy(sections = sections, totp = PasswordTotp("123456", "fixture", 17u))
+                state.value.copy(
+                    sections = sections,
+                    otp = PasswordOtp(
+                        PasswordOtpKind.Totp, "123456", "123 456", null, "fixture",
+                        17u, 30u, 30u, null, null
+                    )
+                )
         }
         override fun lock() {
             authentication.lock()
             state.value =
-                state.value.copy(sections = null, totp = null, edit = null)
+                state.value.copy(sections = null, otp = null, edit = null)
         }
         private fun field(id: ULong, reveal: Boolean) {
             lastId = id
@@ -309,7 +316,9 @@ class EntryViewerTest {
             lastId = id
             android.util.Log.i("IronStorage99", "copy-field-$id")
         }
-        override fun copyTotp() = Unit
+        override fun refreshOtp() = Unit
+        override fun advanceHotp() = error("TOTP fixture cannot consume a HOTP counter")
+        override fun copyOtp() = Unit
         override fun edit(id: ULong) {
             lastId = id
             state.value =

android/app/src/androidTest/kotlin/de/rfc1437/ironstorage/PasswordScreenTest.kt

@@ -209,7 +209,9 @@ class PasswordScreenTest {
         override fun reveal(id: ULong) = Unit
         override fun hide(id: ULong) = Unit
         override fun copy(id: ULong) = Unit
-        override fun copyTotp() = Unit
+        override fun copyOtp() = Unit
+        override fun refreshOtp() = Unit
+        override fun advanceHotp() = Unit
         override fun edit(id: ULong) = Unit
         override fun dismissEdit() = Unit
         override fun saveEdit(value: String) = Unit

android/app/src/androidTest/kotlin/de/rfc1437/ironstorage/Tier2WindowTest.kt

@@ -54,7 +54,10 @@ class Tier2WindowTest {
         val model = ShellViewModel(
             AdaptiveShellTest.Fixture(), original.onboarding, original.passwords,
             original.home, original.search, authentication, original.editor,
-            SettingsScreenTest.Fixture(), SavedStateHandle(mapOf("shell.tab" to "Preferences"))
+            SettingsScreenTest.Fixture(), original.totp,
+            SavedStateHandle(
+                mapOf("shell.tab" to "Preferences")
+            )
         )
         compose.runOnIdle { compose.activity.viewModelStore.put("tier2-window-fixture", model) }
         lateinit var inputMode: InputModeManager

android/app/src/androidTest/kotlin/de/rfc1437/ironstorage/TotpScreenTest.kt

@@ -0,0 +1,209 @@
+package de.rfc1437.ironstorage
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.semantics.SemanticsActions
+import androidx.compose.ui.test.ExperimentalTestApi
+import androidx.compose.ui.test.assertIsDisplayed
+import androidx.compose.ui.test.assertTextEquals
+import androidx.compose.ui.test.junit4.v2.createAndroidComposeRule
+import androidx.compose.ui.test.onAllNodesWithText
+import androidx.compose.ui.test.onLast
+import androidx.compose.ui.test.onNodeWithTag
+import androidx.compose.ui.test.onNodeWithText
+import androidx.compose.ui.test.performClick
+import androidx.compose.ui.test.performSemanticsAction
+import androidx.compose.ui.text.TextLayoutResult
+import androidx.compose.ui.unit.Density
+import androidx.test.platform.app.InstrumentationRegistry
+import de.rfc1437.ironstorage.core.PasswordOtp
+import de.rfc1437.ironstorage.core.PasswordOtpKind
+import de.rfc1437.ironstorage.core.PasswordRepository
+import de.rfc1437.ironstorage.core.TotpRepository
+import de.rfc1437.ironstorage.core.TotpState
+import de.rfc1437.ironstorage.features.TotpScreen
+import java.util.concurrent.CountDownLatch
+import java.util.concurrent.TimeUnit
+import kotlinx.coroutines.flow.MutableStateFlow
+import org.junit.Assert.assertEquals
+import org.junit.Assume.assumeTrue
+import org.junit.Rule
+import org.junit.Test
+
+@OptIn(ExperimentalTestApi::class)
+class TotpScreenTest {
+    @get:Rule val compose = createAndroidComposeRule<MainActivity>()
+
+    private fun display(fixture: Fixture, fontScale: Float = 1f) {
+        compose.activity.runOnUiThread {
+            compose.activity.setProtectedTestContent {
+                val density = LocalDensity.current
+                CompositionLocalProvider(
+                    LocalDensity provides Density(density.density, fontScale)
+                ) {
+                    MaterialTheme { TotpScreen(fixture, fixture.base.authentication) }
+                }
+            }
+        }
+    }
+
+    @Test fun catalogRequiresExplicitUnlockAndShowsSharedLargeCode() {
+        val fixture = Fixture()
+        display(fixture)
+        compose.onNodeWithTag("otp-code").assertDoesNotExist()
+        compose.onNodeWithText("Viewer").performClick()
+        compose.onNodeWithText("Unlock").performClick()
+        compose.onNodeWithTag("otp-code").assertTextEquals("123 456")
+        compose.onNodeWithText("17 seconds remaining").assertIsDisplayed()
+        compose.onNodeWithText("Copy code").performClick()
+        assertEquals(1, fixture.copies)
+        compose.onNodeWithText("Refresh code").performClick()
+        assertEquals(1, fixture.refreshes)
+        compose.onNodeWithText("Lock").performClick()
+        compose.onNodeWithTag("otp-code").assertDoesNotExist()
+        compose.onNodeWithText("Unlock").assertIsDisplayed()
+    }
+
+    @Test fun ticksStopWhenTheCodeComponentLeaves() {
+        val fixture = Fixture()
+        display(fixture)
+        compose.onNodeWithText("Viewer").performClick()
+        compose.onNodeWithText("Unlock").performClick()
+        compose.waitUntil(5000) { fixture.ticks > 0 }
+        compose.onNodeWithText("Back to TOTP entries").performClick()
+        val stopped = fixture.ticks
+        Thread.sleep(1200)
+        compose.waitForIdle()
+        assertEquals(stopped, fixture.ticks)
+    }
+
+    @Test fun largeTextShowsEveryDigitWithoutClipping() {
+        val fixture = Fixture()
+        display(fixture, 3f)
+        compose.onNodeWithText("Viewer").performClick()
+        compose.onNodeWithText("Unlock").performClick()
+        val results = mutableListOf<TextLayoutResult>()
+        compose.onNodeWithTag(
+            "otp-code"
+        ).performSemanticsAction(SemanticsActions.GetTextLayoutResult) {
+            org.junit.Assert.assertTrue(it(results))
+        }
+        org.junit.Assert.assertTrue(results.isNotEmpty())
+        org.junit.Assert.assertFalse(results.single().hasVisualOverflow)
+    }
+
+    @Test fun hotpGenerationRequiresConfirmationAndCancelDoesNotConsume() {
+        val fixture = Fixture(hotp = true)
+        display(fixture)
+        compose.onNodeWithText("Viewer").performClick()
+        compose.onNodeWithText("Unlock").performClick()
+        compose.onNodeWithTag("otp-code").assertDoesNotExist()
+        compose.onNodeWithText("Generate next HOTP code").performClick()
+        compose.onNodeWithText("Cancel").performClick()
+        assertEquals(0, fixture.generations)
+        compose.onNodeWithText("Generate next HOTP code").performClick()
+        compose.onAllNodesWithText("Generate next HOTP code").onLast().performClick()
+        assertEquals(1, fixture.generations)
+        compose.onNodeWithTag("otp-code").assertTextEquals("287 082")
+        compose.onNodeWithText("Copy code").performClick()
+        compose.onNodeWithText("Refresh code").performClick()
+        assertEquals(1, fixture.generations)
+        compose.runOnIdle { fixture.base.authentication.lock() }
+        compose.onNodeWithTag("otp-code").assertDoesNotExist()
+    }
+
+    @Test fun inspectDisposableTotpWithComputerUse() {
+        val arguments = InstrumentationRegistry.getArguments()
+        assumeTrue(arguments.getString("otpInspect") == "true")
+        val fixture = Fixture(hotp = arguments.getString("otpKind") == "hotp")
+        val done = CountDownLatch(1)
+        compose.activity.runOnUiThread {
+            compose.activity.setProtectedTestContent {
+                MaterialTheme {
+                    Column(Modifier.fillMaxSize()) {
+                        TextButton(onClick = { done.countDown() }) { Text("Finish OTP inspection") }
+                        val density = LocalDensity.current
+                        CompositionLocalProvider(
+                            LocalDensity provides
+                                Density(
+                                    density.density,
+                                    arguments.getString("otpFont")?.toFloat() ?: 1f
+                                )
+                        ) {
+                            TotpScreen(fixture, fixture.base.authentication)
+                        }
+                    }
+                }
+            }
+        }
+        compose.waitForIdle()
+        while (!done.await(100, TimeUnit.MILLISECONDS)) {
+            compose.mainClock.advanceTimeBy(100)
+            compose.waitForIdle()
+        }
+    }
+
+    private class Fixture(private val hotp: Boolean = false) : TotpRepository {
+        val base = EntryViewerTest.Fixture()
+        var copies = 0
+        var refreshes = 0
+        var generations = 0
+        var ticks = 0
+        override val state = MutableStateFlow(
+            TotpState(
+                rows = base.state.value.rows,
+                hasCatalog = true
+            )
+        )
+        override val viewer = object : PasswordRepository by base {
+            override fun unlock(passphrase: String) {
+                base.unlock(passphrase)
+                if (hotp) {
+                    base.state.value = base.state.value.copy(
+                        otp = PasswordOtp(
+                            PasswordOtpKind.Hotp, null, null, "RFC", "alice",
+                            null, null, null, null, 1u
+                        )
+                    )
+                }
+            }
+            override fun copyOtp() {
+                copies += 1
+            }
+            override fun tickOtp() {
+                ticks += 1
+            }
+            override fun refreshOtp() {
+                refreshes += 1
+            }
+            override fun advanceHotp() {
+                generations += 1
+                base.state.value = base.state.value.copy(
+                    otp = PasswordOtp(
+                        PasswordOtpKind.Hotp, "287082", "287 082", "RFC", "alice",
+                        null, null, null, 1u, 2u
+                    )
+                )
+            }
+        }
+        override fun enter(selected: String?, revision: String?) = Unit
+        override fun reload() = Unit
+        override fun open(id: String, revision: String) {
+            state.value =
+                state.value.copy(detail = true)
+        }
+        override fun back() {
+            viewer.leave()
+            state.value = state.value.copy(detail = false)
+        }
+        override fun discover(passphrase: String) = Unit
+        override fun cancel() = Unit
+        override fun leave() = viewer.leave()
+    }
+}

android/app/src/main/kotlin/de/rfc1437/ironstorage/ShellModule.kt

@@ -18,12 +18,14 @@ import de.rfc1437.ironstorage.core.NativePasswordRepository
 import de.rfc1437.ironstorage.core.NativePrivateSession
 import de.rfc1437.ironstorage.core.NativeSearchRepository
 import de.rfc1437.ironstorage.core.NativeSettingsRepository
+import de.rfc1437.ironstorage.core.NativeTotpRepository
 import de.rfc1437.ironstorage.core.OnboardingRepository
 import de.rfc1437.ironstorage.core.PasswordRepository
 import de.rfc1437.ironstorage.core.SearchRepository
 import de.rfc1437.ironstorage.core.SettingsPlatform
 import de.rfc1437.ironstorage.core.SettingsRepository
 import de.rfc1437.ironstorage.core.ShellRepository
+import de.rfc1437.ironstorage.core.TotpRepository
 import de.rfc1437.ironstorage.platform.AndroidKeystoreAdapter
 import de.rfc1437.ironstorage.platform.AndroidSecretClipboard
 import de.rfc1437.ironstorage.platform.AndroidSettingsPlatform
@@ -108,6 +110,25 @@ object ShellModule {
         AndroidSecretClipboard(context)
     )
 
+    @Provides
+    @Singleton
+    fun totpRepository(
+        session: NativePrivateSession,
+        authentication: NativeAuthenticationRepository,
+        @ApplicationContext context: Context
+    ): TotpRepository {
+        val scope = CoroutineScope(SupervisorJob() + Dispatchers.Main.immediate)
+        val viewer =
+            NativePasswordRepository(
+                session,
+                scope,
+                authentication,
+                Dispatchers.IO,
+                AndroidSecretClipboard(context)
+            )
+        return NativeTotpRepository(session, authentication, viewer, scope)
+    }
+
     @Provides
     @Singleton
     fun nativeAuthentication(session: NativePrivateSession): NativeAuthenticationRepository =

android/core/src/androidTest/kotlin/de/rfc1437/ironstorage/core/NativeEntryViewerTest.kt

@@ -24,9 +24,14 @@ import org.junit.Test
 
 /** Actual encrypted Rust documents and Kotlin facade, with deterministic OS capabilities. */
 class NativeEntryViewerTest {
+    companion object {
+        // Rust activates one private root per process; each test recreates this disposable root.
+        internal val rootName = "native-controller-${UUID.randomUUID()}"
+    }
+
     @Test fun fieldsEditingCopyMutationsAndTotpExpiryUseTheNativeOwner(): Unit = runBlocking {
         val context = InstrumentationRegistry.getInstrumentation().targetContext
-        val name = "viewer-${UUID.randomUUID()}"
+        val name = rootName
         val roots = listOf(context.filesDir, context.noBackupFilesDir, context.cacheDir).map {
             File(it, name).apply { mkdirs() }.canonicalPath
         }
@@ -168,8 +173,8 @@ class NativeEntryViewerTest {
             assertTrue(sensitive.all { it.value == "Hidden" && !it.revealed && !it.selectable })
             assertEquals(2, fields().count { it.label == "Custom" })
             assertTrue(fields().any { it.value == "First line\nSecond line" && it.multiline })
-            assertNotNull(repository.state.value.totp)
-            assertTrue(repository.state.value.totp!!.remainingSeconds in 1uL..30uL)
+            assertNotNull(repository.state.value.otp)
+            assertTrue(repository.state.value.otp!!.remainingSeconds!! in 1uL..30uL)
             for (event in listOf(
                 AuthenticationLifecycle.Background,
                 AuthenticationLifecycle.DeviceLocked,
@@ -184,7 +189,7 @@ class NativeEntryViewerTest {
                     authentication.lifecycle(event)
                     assertNull(repository.state.value.sections)
                     assertNull(repository.state.value.edit)
-                    assertNull(repository.state.value.totp)
+                    assertNull(repository.state.value.otp)
                     assertNull(clipboard.value)
                     assertFalse(authentication.state.value.unlocked)
                 }
@@ -227,7 +232,7 @@ class NativeEntryViewerTest {
             request { repository.lock() }
             assertNull(repository.state.value.sections)
             assertNull(repository.state.value.edit)
-            assertNull(repository.state.value.totp)
+            assertNull(repository.state.value.otp)
             withTimeout(10000) { while (clipboard.value != null) delay(20) }
             request { repository.unlock(password) }
             authentication.authenticated {
@@ -243,7 +248,7 @@ class NativeEntryViewerTest {
             authentication.authenticated { it.setAuthenticationTimeout(2u) }
             withTimeout(10000) { authentication.state.first { !it.unlocked } }
             withTimeout(10000) { repository.state.first { it.sections == null } }
-            assertNull(repository.state.value.totp)
+            assertNull(repository.state.value.otp)
             assertFalse(authentication.state.value.unlocked)
             authentication.authenticated { it.setAuthenticationTimeout(300u) }
             structuredEditorCreatesMutatesSavesAndRecoversEncryptedDrafts(
@@ -287,6 +292,7 @@ class NativeEntryViewerTest {
         } finally {
             withContext(Dispatchers.Main.immediate) { repository.lock() }
             scope.cancel()
+            roots.forEach { assertTrue(File(it).deleteRecursively()) }
         }
     }
 
@@ -593,7 +599,7 @@ class NativeEntryViewerTest {
         request { settings.setTimeout("300") }
     }
 
-    private class MemoryClipboard : SecretClipboard {
+    internal class MemoryClipboard : SecretClipboard {
         override fun beginCopy(): SecretClipboard = this
 
         @Volatile var value: ByteArray? = null
@@ -605,7 +611,7 @@ class NativeEntryViewerTest {
             value = null
         }
     }
-    private class MemoryKeystore : AndroidKeystore {
+    internal class MemoryKeystore : AndroidKeystore {
         private val keys = mutableSetOf<String>()
         val keyCount get() = keys.size
         var invalidated = false

android/core/src/androidTest/kotlin/de/rfc1437/ironstorage/core/NativeOtpPresentationTest.kt

@@ -0,0 +1,187 @@
+package de.rfc1437.ironstorage.core
+
+import androidx.test.platform.app.InstrumentationRegistry
+import de.rfc1437.ironstorage.bridge.generated.MobileClock
+import de.rfc1437.ironstorage.bridge.generated.MobileEntryEditorFieldKind
+import de.rfc1437.ironstorage.bridge.generated.MobileEntryEditorInput
+import java.io.File
+import java.util.concurrent.CountDownLatch
+import java.util.concurrent.TimeUnit
+import java.util.concurrent.atomic.AtomicLong
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.SupervisorJob
+import kotlinx.coroutines.async
+import kotlinx.coroutines.cancel
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.first
+import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.withContext
+import kotlinx.coroutines.withTimeout
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNotEquals
+import org.junit.Assert.assertNull
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class NativeOtpPresentationTest {
+    @Test fun catalogCodesBoundariesHotpAndLifecycleUseRust(): Unit = runBlocking {
+        val context = InstrumentationRegistry.getInstrumentation().targetContext
+        val name = NativeEntryViewerTest.rootName
+        val roots = listOf(context.filesDir, context.noBackupFilesDir, context.cacheDir).map {
+            File(it, name).apply { mkdirs() }.canonicalPath
+        }
+        val monotonic = AtomicLong(0)
+        val wall = AtomicLong(59)
+        val session = NativePrivateSession(context, {
+            PrivateDirectories(roots[0], roots[1], roots[2])
+        }, NativeEntryViewerTest.MemoryKeystore())
+        val scope = CoroutineScope(SupervisorJob() + Dispatchers.Main.immediate)
+        val memoryClipboard = NativeEntryViewerTest.MemoryClipboard()
+        var expireCopy = false
+        val clipboard = object : SecretClipboard by memoryClipboard {
+            override fun beginCopy(): SecretClipboard {
+                if (expireCopy) wall.set(60)
+                return memoryClipboard
+            }
+        }
+        val authentication =
+            NativeAuthenticationRepository(
+                session,
+                scope,
+                Dispatchers.IO,
+                object : MobileClock {
+                    override fun monotonicMilliseconds() = monotonic.get().toULong()
+                }
+            )
+        val viewer = NativePasswordRepository(
+            session,
+            scope,
+            authentication,
+            Dispatchers.IO,
+            clipboard,
+            { wall.get().toULong() }
+        )
+        val catalog = NativeTotpRepository(session, authentication, viewer, scope)
+        val passphrase = "public-otp-fixture"
+        suspend fun view(action: () -> Unit): PasswordState {
+            withContext(Dispatchers.Main.immediate) { action() }
+            return withTimeout(30000) { viewer.state.first { !it.loading } }
+        }
+        try {
+            withContext(Dispatchers.IO) {
+                session.initialize()
+                val setup = session.storage().androidOnboarding(session.backend())
+                val key = requireNotNull(setup.generate("OTP fixture", passphrase).selectedKey)
+                setup.setupLocal(key, passphrase)
+            }
+            authentication.authenticated { auth ->
+                for ((entry, uri) in listOf(
+                    "timed" to
+                        "otpauth://totp/RFC:alice?secret=GEZDGNBVGY3TQOJQGEZDGNBVGY3TQOJQ&digits=8&issuer=RFC",
+                    "counter" to
+                        "otpauth://hotp/RFC:alice?secret=GEZDGNBVGY3TQOJQGEZDGNBVGY3TQOJQ&counter=0&issuer=RFC"
+                )) {
+                    val draft = auth.beginCreateEntry("", entry, passphrase)
+                    val page = auth.addEntryEditorField(
+                        draft.id,
+                        MobileEntryEditorFieldKind.OTP_URI,
+                        null,
+                        uri
+                    )
+                    auth.saveEntryEditor(
+                        draft.id,
+                        page.fields.map {
+                            MobileEntryEditorInput(it.id, it.name, it.value.orEmpty())
+                        }
+                    )
+                }
+                auth.setAuthenticationTimeout(2u)
+            }
+            withContext(Dispatchers.Main.immediate) {
+                authentication.lock()
+                catalog.enter(null, null)
+            }
+            val cached = withTimeout(30000) { catalog.state.first { !it.loading } }
+            assertNull(cached.error)
+            assertTrue(cached.hasCatalog)
+            assertEquals(listOf("timed"), cached.rows.map { it.title })
+            assertFalse(authentication.state.value.unlocked)
+            assertNull(viewer.state.value.otp)
+            val row = cached.rows.single()
+            view { catalog.open(row.id, row.revision) }
+            assertNull(viewer.state.value.otp)
+            val opened = view { viewer.unlock(passphrase) }
+            assertNull(opened.error)
+            assertEquals("9428 7082", requireNotNull(opened.otp).groupedCode)
+            assertEquals(1uL, requireNotNull(opened.otp).remainingSeconds)
+            val entered = CountDownLatch(1)
+            val release = CountDownLatch(1)
+            val observation = scope.async {
+                runCatching {
+                    authentication.observe { auth ->
+                        val value = auth.state()
+                        entered.countDown()
+                        assertTrue(release.await(10, TimeUnit.SECONDS))
+                        value
+                    }
+                }
+            }
+            withContext(Dispatchers.IO) { assertTrue(entered.await(10, TimeUnit.SECONDS)) }
+            val userAction = scope.async { authentication.authenticated { it.state() } }
+            withTimeout(10000) { authentication.state.first { it.busy } }
+            release.countDown()
+            assertTrue(observation.await().isFailure)
+            assertTrue(userAction.await().unlocked)
+            assertTrue(authentication.state.value.unlocked)
+            view { viewer.copyOtp() }
+            withTimeout(10000) { while (memoryClipboard.value == null) delay(20) }
+            assertEquals("94287082", memoryClipboard.value!!.toString(Charsets.UTF_8))
+            withContext(Dispatchers.Main.immediate) { memoryClipboard.clear() }
+            expireCopy = true
+            val rejectedCopy = view { viewer.copyOtp() }
+            assertTrue(rejectedCopy.error != null)
+            assertNull(memoryClipboard.value)
+            expireCopy = false
+            wall.set(60)
+            monotonic.set(1000)
+            withContext(Dispatchers.Main.immediate) { viewer.tickOtp() }
+            withTimeout(30000) { viewer.state.first { it.otp?.remainingSeconds == 30uL } }
+            assertEquals(30uL, viewer.state.value.otp!!.remainingSeconds)
+            assertNotEquals("94287082", viewer.state.value.otp!!.code)
+            monotonic.set(2000)
+            withTimeout(10000) {
+                authentication.state.first { !it.unlocked }
+            }
+            assertFalse(authentication.state.value.unlocked)
+            assertNull(memoryClipboard.value)
+            view { viewer.restore("", null, null) }
+            val counter = viewer.state.value.rows.single { it.title == "counter" }
+            view { viewer.activate(counter.id, viewer.state.value.revision) }
+            val pending = view { viewer.unlock(passphrase) }
+            assertEquals(PasswordOtpKind.Hotp, requireNotNull(pending.otp).kind)
+            assertNull(requireNotNull(pending.otp).code)
+            assertEquals(1uL, requireNotNull(pending.otp).nextCounter)
+            val generated = view { viewer.advanceHotp() }
+            assertNull(generated.error)
+            assertEquals("287 082", requireNotNull(generated.otp).groupedCode)
+            assertEquals(1uL, requireNotNull(generated.otp).counter)
+            view { viewer.refreshOtp() }
+            view { viewer.copyOtp() }
+            assertEquals(1uL, viewer.state.value.otp!!.counter)
+            val next = view { viewer.advanceHotp() }
+            assertEquals("359152", requireNotNull(next.otp).code)
+            assertEquals(2uL, requireNotNull(next.otp).counter)
+            withContext(Dispatchers.Main.immediate) {
+                authentication.lifecycle(AuthenticationLifecycle.Background)
+                assertNull(viewer.state.value.otp)
+                assertNull(viewer.state.value.sections)
+                assertNull(memoryClipboard.value)
+            }
+        } finally {
+            withContext(Dispatchers.Main.immediate) { scope.cancel() }
+            roots.forEach { File(it).deleteRecursively() }
+        }
+    }
+}

android/core/src/main/kotlin/de/rfc1437/ironstorage/core/NativeAuthenticationRepository.kt

@@ -26,7 +26,10 @@ import kotlinx.coroutines.withContext
 class NativeAuthenticationRepository(
     private val session: NativePrivateSession,
     private val scope: CoroutineScope,
-    private val io: CoroutineDispatcher
+    private val io: CoroutineDispatcher,
+    private val clock: MobileClock = object : MobileClock {
+        override fun monotonicMilliseconds(): ULong = SystemClock.elapsedRealtime().toULong()
+    }
 ) : AuthenticationRepository {
     internal fun text(id: Int) = session.text(id)
 
@@ -38,9 +41,6 @@ class NativeAuthenticationRepository(
     private var revocation: Job? = null
 
     @Volatile private var current: MobileAuthentication? = null
-    private val clock = object : MobileClock {
-        override fun monotonicMilliseconds(): ULong = SystemClock.elapsedRealtime().toULong()
-    }
     init {
         presentation.onWindowFocusLost = { lifecycle(AuthenticationLifecycle.Background) }
         scope.launch {
@@ -69,9 +69,17 @@ class NativeAuthenticationRepository(
         }
 
     internal suspend fun <T> authenticated(block: (MobileAuthentication) -> T): T =
+        access(true, block)
+
+    internal suspend fun <T> observe(block: (MobileAuthentication) -> T): T? =
         withContext(kotlinx.coroutines.Dispatchers.Main.immediate) {
-            val ticket = sequence.incrementAndGet()
-            mutable.value = mutable.value.copy(busy = true, failure = null)
+            if (mutable.value.busy) null else access(false, block)
+        }
+
+    private suspend fun <T> access(showBusy: Boolean, block: (MobileAuthentication) -> T): T =
+        withContext(kotlinx.coroutines.Dispatchers.Main.immediate) {
+            val ticket = if (showBusy) sequence.incrementAndGet() else sequence.get()
+            if (showBusy) mutable.value = mutable.value.copy(busy = true, failure = null)
             operation.withLock {
                 revocation?.join()
                 if (ticket != sequence.get()) throw cancelled(session)
@@ -81,7 +89,7 @@ class NativeAuthenticationRepository(
                         if (ticket != sequence.get()) throw cancelled(session)
                         val result = block(authentication)
                         if (ticket != sequence.get()) {
-                            authentication.manualLock()
+                            if (showBusy) authentication.manualLock()
                             throw cancelled(session)
                         }
                         result
@@ -114,7 +122,11 @@ class NativeAuthenticationRepository(
                     if (ticket == sequence.get()) unavailable()
                     throw error
                 } finally {
-                    if (ticket == sequence.get()) mutable.value = mutable.value.copy(busy = false)
+                    if (showBusy &&
+                        ticket == sequence.get()
+                    ) {
+                        mutable.value = mutable.value.copy(busy = false)
+                    }
                 }
             }
         }

android/core/src/main/kotlin/de/rfc1437/ironstorage/core/NativePasswordRepository.kt

@@ -9,6 +9,8 @@ import de.rfc1437.ironstorage.bridge.generated.MobileClipboardWait
 import de.rfc1437.ironstorage.bridge.generated.MobileEntryPresentation
 import de.rfc1437.ironstorage.bridge.generated.MobileMutationAction
 import de.rfc1437.ironstorage.bridge.generated.MobileMutationRequest
+import de.rfc1437.ironstorage.bridge.generated.MobileOtpCodeKind
+import de.rfc1437.ironstorage.bridge.generated.MobileOtpCodePresentation
 import de.rfc1437.ironstorage.bridge.generated.MobilePasswordFfiException
 import de.rfc1437.ironstorage.bridge.generated.MobilePasswordNavigation
 import de.rfc1437.ironstorage.bridge.generated.MobilePasswordRowKind
@@ -16,6 +18,7 @@ import de.rfc1437.ironstorage.bridge.generated.MobilePlatformFfiException
 import de.rfc1437.ironstorage.bridge.generated.MobilePrivateStorageFfiException
 import de.rfc1437.ironstorage.bridge.generated.clearMobileEntryCopy
 import de.rfc1437.ironstorage.bridge.generated.copyMobileEntryClearing
+import de.rfc1437.ironstorage.bridge.generated.mobileOtpWindowCurrent
 import java.util.concurrent.atomic.AtomicLong
 import kotlinx.coroutines.CompletableDeferred
 import kotlinx.coroutines.CoroutineDispatcher
@@ -24,6 +27,9 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.collectLatest
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.runBlocking
 import kotlinx.coroutines.sync.Mutex
@@ -35,7 +41,8 @@ class NativePasswordRepository(
     private val scope: CoroutineScope,
     private val authentication: NativeAuthenticationRepository,
     private val io: CoroutineDispatcher,
-    private val clipboard: SecretClipboard
+    private val clipboard: SecretClipboard,
+    private val unixSeconds: () -> ULong = ::unixSeconds
 ) : PasswordRepository {
     private val mutable = MutableStateFlow(PasswordState())
     override val state: StateFlow<PasswordState> = mutable
@@ -51,31 +58,76 @@ class NativePasswordRepository(
             }
         }
         scope.coroutineContext[kotlinx.coroutines.Job]?.invokeOnCompletion { registration.close() }
+        // Hidden codes still expire; only the composed UI requests decryption/countdown refresh.
         scope.launch {
+            mutable.map { state ->
+                state.otp?.takeIf { it.kind == PasswordOtpKind.Totp && it.code != null }?.validUntil
+            }.distinctUntilChanged().collectLatest { end ->
+                if (end != null) {
                     while (true) {
-                delay(1000)
+                        delay(1000L - Math.floorMod(System.currentTimeMillis(), 1000L))
+                        expireOtp()
+                    }
+                }
+            }
+        }
+    }
+    private suspend fun expireOtp() {
         val current = mutable.value
-                if (current.totp != null && !current.loading &&
-                    authentication.state.value.unlocked &&
-                    !authentication.state.value.busy
+        val code = current.otp ?: return
+        if (code.validUntil != null && code.period != null && code.code != null) {
+            val valid = withContext(io) {
+                mobileOtpWindowCurrent(code.validUntil, code.period, unixSeconds())
+            }
+            if (!valid &&
+                mutable.value.otp === code
             ) {
-                    content(false) { current ->
-                        val detail = authentication.authenticated { auth ->
-                            auth.refreshEntryPresentation(
-                                requireNotNull(current.selected).path,
+                mutable.value = current.copy(otp = code.masked())
+            }
+        }
+    }
+    override fun tickOtp() {
+        if (mutable.value.otp?.kind != PasswordOtpKind.Totp) return
+        scope.launch {
+            expireOtp()
+            if (!mutex.isLocked && !mutable.value.loading &&
+                authentication.state.value.unlocked && !authentication.state.value.busy
+            ) {
+                refreshOtp(false)
+            }
+        }
+    }
+    override fun refreshOtp() = refreshOtp(true)
+    private fun refreshOtp(userActivity: Boolean) = content(userActivity) { current ->
+        val code = authentication.observe { auth ->
+            auth.presentedOtpCode(
+                current.entryPath(),
                 requireNotNull(current.documentRevision),
-                                unixSeconds()
-                            ).totp
-                        }
-                        current.copy(
-                            totp = detail?.let {
-                                PasswordTotp(it.code, it.account, it.remainingSeconds)
-                            }
+                unixSeconds(),
+                current.otp?.counter
             )
         }
+        if (code == null) current else current.copy(otp = code.toFacade())
     }
+    override fun advanceHotp() = content { current ->
+        val code = authentication.authenticated { auth ->
+            auth.advancePresentedHotp(
+                current.entryPath(),
+                requireNotNull(current.documentRevision),
+                true
+            )
         }
+        val page = authentication.authenticated { auth ->
+            auth.refreshEntryPresentation(current.entryPath(), code.documentRevision, unixSeconds())
         }
+        val folder = session.storage().passwordNavigation(current.path, null, null, false)
+        val refreshed = session.storage().passwordNavigation(
+            current.path,
+            current.selected?.id,
+            folder.revision,
+            false
+        ).toFacade()
+        if (refreshed.selected == null) refreshed else refreshed.present(page, code)
     }
     override fun restore(path: String, selected: String?, revision: String?) =
         navigate(path, selected, revision, false)
@@ -122,16 +174,18 @@ class NativePasswordRepository(
                 false
             ).toFacade()
             if (verified.selected == null) return@run verified
-            val page = authentication.authenticated { auth ->
-                auth.navigationEntry(
+            val (page, code) = authentication.authenticated { auth ->
+                val page = auth.navigationEntry(
                     current.path,
                     selected.id,
                     current.revision,
                     passphrase.ifEmpty { null },
-                    (System.currentTimeMillis() / 1000).toULong()
+                    unixSeconds()
                 )
+                page to
+                    auth.presentedOtpCode(selected.path, page.page.revision, unixSeconds(), null)
             }
-            verified.present(page)
+            verified.present(page, code)
         }
     }
     override fun leave() {
@@ -216,7 +270,11 @@ class NativePasswordRepository(
                 value
             )
         }
-        val page = authentication.authenticated { it.entryPage(current.entryPath(), unixSeconds()) }
+        val (page, code) = authentication.authenticated {
+            val page = it.entryPage(current.entryPath(), unixSeconds())
+            page to
+                it.presentedOtpCode(current.entryPath(), page.page.revision, unixSeconds(), null)
+        }
         val folder = session.storage().passwordNavigation(current.path, null, null, false)
         val refreshed = session.storage().passwordNavigation(
             current.path,
@@ -224,27 +282,35 @@ class NativePasswordRepository(
             folder.revision,
             false
         ).toFacade()
-        if (refreshed.selected == null) refreshed else refreshed.present(page)
+        if (refreshed.selected == null) refreshed else refreshed.present(page, code)
     }
     override fun copy(id: ULong) = copyValue { auth, current ->
         auth.copyPresentedEntryField(
             current.entryPath(),
             id,
             requireNotNull(current.documentRevision)
-        )
+        ) to null
     }
-    override fun copyTotp() = copyValue { auth, current ->
-        auth.copyPresentedTotpCode(
+    override fun copyOtp() = copyValue { auth, current ->
+        val now = unixSeconds()
+        val code = auth.presentedOtpCode(
             current.entryPath(),
             requireNotNull(current.documentRevision),
-            unixSeconds()
+            now,
+            current.otp?.counter
         )
+        auth.copyPresentedOtpCode(
+            current.entryPath(),
+            requireNotNull(current.documentRevision),
+            now,
+            current.otp?.counter
+        ) to code
     }
     private fun copyValue(
         get: (de.rfc1437.ironstorage.bridge.generated.MobileAuthentication, PasswordState) ->
-        de.rfc1437.ironstorage.bridge.generated.MobileEntryCopy
+        Pair<de.rfc1437.ironstorage.bridge.generated.MobileEntryCopy, MobileOtpCodePresentation?>
     ) = content { current ->
-        val copy = authentication.authenticated { get(it, current) }
+        val (copy, code) = authentication.authenticated { get(it, current) }
         val ticket = sequence.get()
         val owned = clipboard.beginCopy()
         val written = CompletableDeferred<Boolean>()
@@ -258,6 +324,15 @@ class NativePasswordRepository(
                 if (!authentication.state.value.unlocked) {
                     throw MobilePlatformFfiException.Cancelled()
                 }
+                if (code?.kind == MobileOtpCodeKind.TOTP &&
+                    !mobileOtpWindowCurrent(
+                        requireNotNull(code.validUntil),
+                        requireNotNull(code.period),
+                        unixSeconds()
+                    )
+                ) {
+                    throw MobilePlatformFfiException.Cancelled()
+                }
                 clipboardAccess { owned.write(value) }
                 written.complete(true)
                 Unit
@@ -372,19 +447,23 @@ class NativePasswordRepository(
             return
         }
         if (userActivity) authentication.touch()
-        run(false) { action(current) }
+        run(false, userActivity) { action(current) }
     }
-    private fun run(clear: Boolean = true, action: suspend () -> PasswordState) {
+    private fun run(
+        clear: Boolean = true,
+        showLoading: Boolean = true,
+        action: suspend () -> PasswordState
+    ) {
         val ticket = sequence.incrementAndGet()
         mutable.value =
             (if (clear) mutable.value.cleared() else mutable.value).copy(
-                loading = true,
+                loading = showLoading,
                 error = null
             )
         scope.launch {
             mutex.withLock {
                 if (sequence.get() != ticket) return@withLock
-                val result = try {
+                var result = try {
                     withContext(io) { action() }
                 } catch (error: MobilePasswordFfiException.Failed) {
                     mutable.value.copy(error = error.detail, selected = null)
@@ -402,6 +481,17 @@ class NativePasswordRepository(
                         selected = null
                     )
                 }
+                val code = result.otp
+                if (code?.kind == PasswordOtpKind.Totp && code.code != null &&
+                    code.validUntil != null &&
+                    code.period != null
+                ) {
+                    val valid =
+                        withContext(io) {
+                            mobileOtpWindowCurrent(code.validUntil, code.period, unixSeconds())
+                        }
+                    if (!valid) result = result.copy(otp = code.masked())
+                }
                 if (sequence.get() == ticket) {
                     mutable.value =
                         (if (authentication.state.value.unlocked) result else result.cleared())
@@ -439,13 +529,16 @@ internal fun MobilePasswordNavigation.toFacade(): PasswordState = PasswordState(
 private fun unixSeconds() = (System.currentTimeMillis() / 1000).toULong()
 private fun PasswordState.cleared() = copy(
     sections = null,
-    totp = null,
+    otp = null,
     documentRevision = null,
     edit = null,
     mutation = null,
     notice = null
 )
-private fun PasswordState.present(value: MobileEntryPresentation) = copy(
+private fun PasswordState.present(
+    value: MobileEntryPresentation,
+    code: MobileOtpCodePresentation?
+) = copy(
     documentRevision = value.page.revision,
     sections = value.page.sections.map { section ->
         PasswordSection(
@@ -460,11 +553,19 @@ private fun PasswordState.present(value: MobileEntryPresentation) = copy(
             }
         )
     },
-    totp = value.totp?.let { PasswordTotp(it.code, it.account, it.remainingSeconds) },
+    otp = code?.toFacade(),
     notice = value.cacheNotice,
     edit = null,
     mutation = null
 )
+private fun PasswordOtp.masked() = copy(code = null, groupedCode = null, remainingSeconds = 0u)
+private fun MobileOtpCodePresentation.toFacade() = PasswordOtp(
+    when (kind) {
+        MobileOtpCodeKind.TOTP -> PasswordOtpKind.Totp
+        MobileOtpCodeKind.HOTP -> PasswordOtpKind.Hotp
+    },
+    code, groupedCode, issuer, account, remainingSeconds, period, validUntil, counter, nextCounter
+)
 private fun PasswordMutation.native() = when (this) {
     PasswordMutation.Move -> MobileMutationAction.MOVE
     PasswordMutation.Copy -> MobileMutationAction.COPY

android/core/src/main/kotlin/de/rfc1437/ironstorage/core/NativeTotpRepository.kt

@@ -0,0 +1,131 @@
+package de.rfc1437.ironstorage.core
+
+import de.rfc1437.ironstorage.bridge.NativeBridgeException
+import de.rfc1437.ironstorage.bridge.generated.MobileAuthenticationFfiException
+import de.rfc1437.ironstorage.bridge.generated.MobilePrivateStorageFfiException
+import de.rfc1437.ironstorage.bridge.generated.MobileTotpOperation
+import de.rfc1437.ironstorage.bridge.generated.mobileTotpOperation
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.sync.Mutex
+import kotlinx.coroutines.sync.withLock
+import kotlinx.coroutines.withContext
+
+class NativeTotpRepository(
+    private val session: NativePrivateSession,
+    private val authentication: NativeAuthenticationRepository,
+    override val viewer: PasswordRepository,
+    private val scope: CoroutineScope
+) : TotpRepository {
+    private val mutable = MutableStateFlow(TotpState())
+    override val state: StateFlow<TotpState> = mutable
+    private val serial = Mutex()
+
+    @Volatile private var epoch = 0L
+
+    @Volatile private var discovery: MobileTotpOperation? = null
+
+    init {
+        val cleanup = authentication.presentation.register(::cancel)
+        scope.coroutineContext[Job]?.invokeOnCompletion { cleanup.close() }
+    }
+
+    override fun enter(selected: String?, revision: String?) = load(selected, revision)
+    override fun reload() = load(null, null)
+    private fun load(selected: String?, revision: String?) = run { ticket ->
+        val rows = authentication.authenticated { it.cachedTotpNavigation() }
+        if (ticket == epoch) {
+            mutable.value =
+                mutable.value.copy(
+                    rows = rows.orEmpty().map { it.toFacade() },
+                    hasCatalog =
+                    rows != null
+                )
+            if (selected != null && revision != null) open(selected, revision)
+        }
+    }
+    override fun open(id: String, revision: String) {
+        if (mutable.value.rows.none { it.id == id && it.revision == revision }) return
+        mutable.value = mutable.value.copy(detail = true, error = null)
+        viewer.openSearch(id, revision)
+    }
+    override fun back() {
+        viewer.leave()
+        mutable.value = mutable.value.copy(detail = false)
+        reload()
+    }
+    override fun discover(passphrase: String) = run { ticket ->
+        val active = withContext(Dispatchers.IO) { mobileTotpOperation() }
+        discovery = active
+        if (ticket != epoch) active.cancel()
+        try {
+            val rows = authentication.authenticated {
+                it.unlockTotp(passphrase.ifEmpty { null })
+                it.totpPage(active)
+                it.cachedTotpNavigation()
+            }
+            if (ticket ==
+                epoch
+            ) {
+                mutable.value =
+                    mutable.value.copy(
+                        rows = rows.orEmpty().map { it.toFacade() },
+                        hasCatalog =
+                        rows != null
+                    )
+            }
+        } finally {
+            discovery = null
+            active.close()
+        }
+    }
+    override fun cancel() {
+        epoch += 1
+        discovery?.cancel()
+        mutable.value = mutable.value.copy(loading = false)
+    }
+    override fun leave() {
+        cancel()
+        viewer.leave()
+    }
+    private fun run(action: suspend (Long) -> Unit) {
+        if (mutable.value.loading) return
+        val ticket = epoch
+        mutable.value = mutable.value.copy(loading = true, error = null)
+        scope.launch {
+            serial.withLock {
+                if (ticket != epoch) return@withLock
+                try {
+                    action(ticket)
+                } catch (error: MobileAuthenticationFfiException.Failed) {
+                    if (ticket ==
+                        epoch
+                    ) {
+                        mutable.value =
+                            mutable.value.copy(error = error.title + "\n" + error.detail)
+                    }
+                } catch (_: MobilePrivateStorageFfiException) {
+                    if (ticket ==
+                        epoch
+                    ) {
+                        mutable.value =
+                            mutable.value.copy(error = session.text(R.string.core_private_recovery))
+                    }
+                } catch (_: NativeBridgeException) {
+                    if (ticket ==
+                        epoch
+                    ) {
+                        mutable.value =
+                            mutable.value.copy(error = session.text(R.string.core_update_retry))
+                    }
+                } finally {
+                    if (ticket == epoch) mutable.value = mutable.value.copy(loading = false)
+                }
+            }
+        }
+    }
+}

android/core/src/main/kotlin/de/rfc1437/ironstorage/core/PasswordRepository.kt

@@ -28,8 +28,20 @@ data class PasswordField(
     override fun toString() = "PasswordField(id=$id, [REDACTED])"
 }
 data class PasswordSection(val title: String, val fields: List<PasswordField>)
-data class PasswordTotp(val code: String, val account: String, val remainingSeconds: ULong) {
-    override fun toString() = "PasswordTotp([REDACTED])"
+enum class PasswordOtpKind { Totp, Hotp }
+data class PasswordOtp(
+    val kind: PasswordOtpKind,
+    val code: String?,
+    val groupedCode: String?,
+    val issuer: String?,
+    val account: String,
+    val remainingSeconds: ULong?,
+    val period: ULong?,
+    val validUntil: ULong?,
+    val counter: ULong?,
+    val nextCounter: ULong?
+) {
+    override fun toString() = "PasswordOtp([REDACTED])"
 }
 data class PasswordEdit(
     val id: ULong,
@@ -65,7 +77,7 @@ data class PasswordState(
     val stale: Boolean = false,
     val error: String? = null,
     val sections: List<PasswordSection>? = null,
-    val totp: PasswordTotp? = null,
+    val otp: PasswordOtp? = null,
     val documentRevision: String? = null,
     val notice: String? = null,
     val edit: PasswordEdit? = null,
@@ -85,7 +97,10 @@ interface PasswordRepository {
     fun reveal(id: ULong)
     fun hide(id: ULong)
     fun copy(id: ULong)
-    fun copyTotp()
+    fun copyOtp()
+    fun tickOtp() = Unit
+    fun refreshOtp()
+    fun advanceHotp()
     fun edit(id: ULong)
     fun dismissEdit()
     fun saveEdit(value: String)

android/core/src/main/kotlin/de/rfc1437/ironstorage/core/TotpRepository.kt

@@ -0,0 +1,24 @@
+package de.rfc1437.ironstorage.core
+
+import kotlinx.coroutines.flow.StateFlow
+
+data class TotpState(
+    val rows: List<PasswordRow> = emptyList(),
+    val loading: Boolean = false,
+    val hasCatalog: Boolean = false,
+    val detail: Boolean = false,
+    val error: String? = null
+) {
+    override fun toString() = "TotpState(loading=$loading, [REDACTED])"
+}
+interface TotpRepository {
+    val state: StateFlow<TotpState>
+    val viewer: PasswordRepository
+    fun enter(selected: String?, revision: String?)
+    fun reload()
+    fun open(id: String, revision: String)
+    fun back()
+    fun discover(passphrase: String)
+    fun cancel()
+    fun leave()
+}

android/features/src/main/kotlin/de/rfc1437/ironstorage/features/EntryViewer.kt

@@ -99,23 +99,16 @@ fun LazyListScope.entryViewer(state: PasswordState, repository: PasswordReposito
         }
     }
     state.notice?.let { item { Text(it) } }
-    state.totp?.let { totp ->
+    state.otp?.let { code ->
         item {
-            Column(verticalArrangement = Arrangement.spacedBy(8.dp)) {
-                Text(stringResource(R.string.entry_totp), Modifier.semantics { heading() })
-                Text(totp.account)
-                Text(totp.code, style = MaterialTheme.typography.headlineMedium)
-                Text(
-                    pluralStringResource(
-                        R.plurals.entry_countdown,
-                        totp.remainingSeconds.toInt(),
-                        totp.remainingSeconds.toLong()
+            OtpCodeView(
+                code,
+                state.loading,
+                repository::copyOtp,
+                repository::refreshOtp,
+                repository::advanceHotp,
+                repository::tickOtp
             )
-                )
-                TextButton(enabled = !state.loading, onClick = repository::copyTotp) {
-                    Text(stringResource(R.string.entry_copy_code))
-                }
-            }
         }
     }
     state.sections?.forEach { section ->

android/features/src/main/kotlin/de/rfc1437/ironstorage/features/OtpCodeView.kt

@@ -0,0 +1,159 @@
+package de.rfc1437.ironstorage.features
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.FlowRow
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.text.TextAutoSize
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.LinearProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.CompositionLocalProvider
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalLayoutDirection
+import androidx.compose.ui.platform.testTag
+import androidx.compose.ui.res.pluralStringResource
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.semantics.heading
+import androidx.compose.ui.semantics.semantics
+import androidx.compose.ui.text.font.FontFamily
+import androidx.compose.ui.unit.LayoutDirection
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import androidx.compose.ui.window.DialogProperties
+import androidx.compose.ui.window.SecureFlagPolicy
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.compose.LocalLifecycleOwner
+import androidx.lifecycle.repeatOnLifecycle
+import de.rfc1437.ironstorage.core.PasswordOtp
+import de.rfc1437.ironstorage.core.PasswordOtpKind
+import kotlinx.coroutines.delay
+
+@Composable
+internal fun OtpCodeView(
+    code: PasswordOtp,
+    busy: Boolean,
+    copy: () -> Unit,
+    refresh: () -> Unit,
+    advance: () -> Unit,
+    tick: () -> Unit
+) {
+    val lifecycle = LocalLifecycleOwner.current.lifecycle
+    LaunchedEffect(lifecycle, code.kind) {
+        if (code.kind == PasswordOtpKind.Totp) {
+            lifecycle.repeatOnLifecycle(Lifecycle.State.STARTED) {
+                tick()
+                while (true) {
+                    delay(1000L - Math.floorMod(System.currentTimeMillis(), 1000L))
+                    tick()
+                }
+            }
+        }
+    }
+    var confirmation by remember(code.nextCounter) { mutableStateOf(false) }
+    Column(verticalArrangement = Arrangement.spacedBy(12.dp)) {
+        Text(
+            stringResource(
+                if (code.kind ==
+                    PasswordOtpKind.Totp
+                ) {
+                    R.string.entry_totp
+                } else {
+                    R.string.otp_hotp
+                }
+            ),
+            Modifier.semantics { heading() }
+        )
+        code.issuer?.let { Text(it, style = MaterialTheme.typography.titleLarge) }
+        Text(code.account)
+        code.groupedCode?.let { value ->
+            CompositionLocalProvider(LocalLayoutDirection provides LayoutDirection.Ltr) {
+                Text(
+                    value,
+                    Modifier.fillMaxWidth().testTag("otp-code"),
+                    style = MaterialTheme.typography.displayMedium,
+                    fontFamily = FontFamily.Monospace,
+                    maxLines = 2,
+                    autoSize = TextAutoSize.StepBased(minFontSize = 24.sp, maxFontSize = 48.sp)
+                )
+            }
+        }
+            ?: Text(
+                stringResource(
+                    if (code.kind ==
+                        PasswordOtpKind.Hotp
+                    ) {
+                        R.string.otp_hotp_pending
+                    } else {
+                        R.string.otp_waiting
+                    }
+                )
+            )
+        val period = code.period
+        val remaining = code.remainingSeconds
+        if (code.kind == PasswordOtpKind.Totp && period != null && remaining != null) {
+            LinearProgressIndicator(progress = {
+                (
+                    remaining.toFloat() /
+                        period.toFloat()
+                    ).coerceIn(0f, 1f)
+            }, modifier = Modifier.fillMaxWidth())
+            Text(
+                pluralStringResource(
+                    R.plurals.otp_countdown,
+                    remaining.coerceAtMost(Int.MAX_VALUE.toULong()).toInt(),
+                    remaining.toString()
+                )
+            )
+        }
+        if (code.kind == PasswordOtpKind.Hotp &&
+            code.code != null
+        ) {
+            Text(stringResource(R.string.otp_counter, code.counter.toString()))
+        }
+        FlowRow {
+            TextButton(enabled = !busy && code.code != null, onClick = copy) {
+                Text(stringResource(R.string.entry_copy_code))
+            }
+            TextButton(enabled = !busy, onClick = refresh) {
+                Text(stringResource(R.string.otp_refresh))
+            }
+            if (code.kind ==
+                PasswordOtpKind.Hotp
+            ) {
+                TextButton(enabled = !busy && code.nextCounter != null, onClick = {
+                    confirmation =
+                        true
+                }) { Text(stringResource(R.string.otp_generate_hotp)) }
+            }
+        }
+    }
+    if (confirmation) {
+        ProtectedWindow()
+        AlertDialog(
+            properties = DialogProperties(securePolicy = SecureFlagPolicy.SecureOn),
+            onDismissRequest = { confirmation = false },
+            title = { Text(stringResource(R.string.otp_generate_hotp)) },
+            text = { Text(stringResource(R.string.otp_confirm_hotp, code.nextCounter.toString())) },
+            confirmButton = {
+                TextButton(enabled = !busy, onClick = {
+                    confirmation = false
+                    advance()
+                }) { Text(stringResource(R.string.otp_generate_hotp)) }
+            },
+            dismissButton = {
+                TextButton(onClick = {
+                    confirmation = false
+                }) { Text(stringResource(R.string.auth_cancel)) }
+            }
+        )
+    }
+}

android/features/src/main/kotlin/de/rfc1437/ironstorage/features/ShellScreen.kt

@@ -200,6 +200,10 @@ private fun ShellDestination(
             Modifier.fillMaxSize(),
             leaveOnDispose = false
         )
+        ready && route == ShellRoute.Totp -> {
+            LaunchedEffect(viewModel) { viewModel.openTotp() }
+            TotpScreen(viewModel.totp, viewModel.authentication)
+        }
         ready && route == ShellRoute.Home -> HomeScreen(
             viewModel.home,
             Modifier.fillMaxSize(),

android/features/src/main/kotlin/de/rfc1437/ironstorage/features/ShellViewModel.kt

@@ -15,6 +15,7 @@ import de.rfc1437.ironstorage.core.SettingsRepository
 import de.rfc1437.ironstorage.core.ShellRepository
 import de.rfc1437.ironstorage.core.ShellState
 import de.rfc1437.ironstorage.core.ShellTab
+import de.rfc1437.ironstorage.core.TotpRepository
 import javax.inject.Inject
 import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.asStateFlow
@@ -30,6 +31,7 @@ class ShellViewModel @Inject constructor(
     val authentication: AuthenticationRepository,
     val editor: EditorRepository,
     val settings: SettingsRepository,
+    val totp: TotpRepository,
     private val saved: SavedStateHandle
 ) : ViewModel() {
     val snapshot = repository.snapshot
@@ -71,6 +73,37 @@ class ShellViewModel @Inject constructor(
                 }
             }
         }
+        viewModelScope.launch {
+            totp.state.collect { saved["totp.detail"] = it.detail }
+        }
+        viewModelScope.launch {
+            totp.viewer.state.collect { value ->
+                val selected = value.selected
+                if (!value.loading && value.error == null && selected != null) {
+                    saved["totp.selection"] = selected.id
+                    saved["totp.revision"] = selected.revision
+                }
+            }
+        }
+    }
+    private var totpRestored = false
+    fun openTotp() {
+        if (!totpRestored) {
+            totpRestored = true
+            totp.enter(
+                if (saved.get<Boolean>("totp.detail") ==
+                    true
+                ) {
+                    saved["totp.selection"]
+                } else {
+                    null
+                },
+                saved["totp.revision"]
+            )
+        } else {
+            val selected = totp.viewer.state.value.selected.takeIf { totp.state.value.detail }
+            totp.enter(selected?.id, selected?.revision)
+        }
     }
     private var passwordsRestored = false
     fun openSearch(row: PasswordRow) {
@@ -116,7 +149,7 @@ class ShellViewModel @Inject constructor(
                 settings.cancel()
                 if (authentication.state.value.busy) authentication.cancel()
             }
-            ShellTab.Totp -> Unit
+            ShellTab.Totp -> totp.leave()
         }
     }
     override fun onCleared() {

android/features/src/main/kotlin/de/rfc1437/ironstorage/features/TotpScreen.kt

@@ -0,0 +1,192 @@
+package de.rfc1437.ironstorage.features
+
+import androidx.activity.compose.BackHandler
+import androidx.compose.foundation.clickable
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.BoxWithConstraints
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.material3.Button
+import androidx.compose.material3.CircularProgressIndicator
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.testTag
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.semantics.Role
+import androidx.compose.ui.unit.dp
+import androidx.lifecycle.Lifecycle
+import androidx.lifecycle.compose.LifecycleEventEffect
+import androidx.lifecycle.compose.collectAsStateWithLifecycle
+import de.rfc1437.ironstorage.core.AuthenticationFailureKind
+import de.rfc1437.ironstorage.core.AuthenticationRepository
+import de.rfc1437.ironstorage.core.TotpRepository
+
+@Composable
+fun TotpScreen(repository: TotpRepository, authentication: AuthenticationRepository) {
+    val state by repository.state.collectAsStateWithLifecycle()
+    val entry by repository.viewer.state.collectAsStateWithLifecycle()
+    val lease by authentication.state.collectAsStateWithLifecycle()
+    var manual by remember { mutableStateOf(false) }
+    var discovery by remember { mutableStateOf(false) }
+    var requested by remember { mutableStateOf(false) }
+    LifecycleEventEffect(Lifecycle.Event.ON_STOP) { repository.leave() }
+    BackHandler(state.detail) { repository.back() }
+    androidx.compose.runtime.LaunchedEffect(lease.failure, state.loading, entry.loading) {
+        if (requested && !state.loading && !entry.loading && !lease.busy) {
+            requested = false
+            if (lease.failure?.kind == AuthenticationFailureKind.PassphraseRequired ||
+                lease.failure?.kind == AuthenticationFailureKind.BiometryUnavailable
+            ) {
+                manual = true
+            }
+        }
+    }
+    val requestCatalog = {
+        discovery = true
+        requested = true
+        repository.discover("")
+    }
+    val requestUnlock = {
+        discovery = false
+        requested = true
+        repository.viewer.unlock("")
+    }
+    BoxWithConstraints(Modifier.fillMaxSize()) {
+        val expanded = maxWidth >= 600.dp
+        Row(Modifier.fillMaxSize()) {
+            if (expanded || !state.detail) {
+                LazyColumn(
+                    Modifier.weight(1f).padding(16.dp).testTag("totp-list"),
+                    verticalArrangement = Arrangement.spacedBy(12.dp)
+                ) {
+                    item {
+                        Text(
+                            stringResource(R.string.entry_totp),
+                            style = MaterialTheme.typography.headlineMedium
+                        )
+                        TextButton(
+                            enabled = !state.loading && !lease.busy,
+                            onClick = requestCatalog
+                        ) {
+                            Text(stringResource(R.string.totp_refresh_catalog))
+                        }
+                        if (state.loading) {
+                            CircularProgressIndicator()
+                            TextButton(onClick = repository::cancel) {
+                                Text(stringResource(R.string.auth_cancel))
+                            }
+                        }
+                        state.error?.let { Text(it, color = MaterialTheme.colorScheme.error) }
+                        if (!state.hasCatalog) {
+                            Text(stringResource(R.string.totp_needs_catalog))
+                        } else if (state.rows.isEmpty()) {
+                            Text(stringResource(R.string.totp_empty))
+                        }
+                    }
+                    items(state.rows, key = { it.id }) { row ->
+                        Column(
+                            Modifier.fillMaxWidth().clickable(
+                                enabled = !state.loading,
+                                role = Role.Button,
+                                onClick = {
+                                    repository.open(row.id, row.revision)
+                                }
+                            ).padding(vertical = 12.dp)
+                        ) {
+                            Text(row.title, style = MaterialTheme.typography.titleMedium)
+                            Text(row.detail)
+                        }
+                    }
+                }
+            }
+            if (expanded || state.detail) {
+                LazyColumn(
+                    Modifier.weight(1f).padding(16.dp).testTag("totp-detail"),
+                    verticalArrangement = Arrangement.spacedBy(12.dp)
+                ) {
+                    item {
+                        if (state.detail) {
+                            TextButton(onClick = repository::back) {
+                                Text(stringResource(R.string.totp_back))
+                            }
+                        }
+                        entry.selected?.let {
+                            Text(it.title, style = MaterialTheme.typography.headlineSmall)
+                        }
+                        if (entry.loading) CircularProgressIndicator()
+                        entry.error?.let { Text(it, color = MaterialTheme.colorScheme.error) }
+                        if (!state.detail) {
+                            Text(stringResource(R.string.totp_choose))
+                        } else if (entry.stale) {
+                            Text(stringResource(R.string.totp_stale))
+                        } else if (entry.selected != null &&
+                            (!lease.unlocked || entry.sections == null)
+                        ) {
+                            Button(
+                                enabled = !entry.loading && !lease.busy,
+                                onClick = requestUnlock
+                            ) {
+                                Text(stringResource(R.string.password_unlock))
+                            }
+                            TextButton(enabled = !lease.busy, onClick = {
+                                discovery = false
+                                manual =
+                                    true
+                            }) { Text(stringResource(R.string.auth_manual)) }
+                            if (lease.busy) {
+                                TextButton(onClick = authentication::cancel) {
+                                    Text(stringResource(R.string.auth_cancel))
+                                }
+                            }
+                        } else if (lease.unlocked && entry.sections != null) {
+                            entry.otp?.let {
+                                OtpCodeView(
+                                    it,
+                                    entry.loading,
+                                    repository.viewer::copyOtp,
+                                    repository.viewer::refreshOtp,
+                                    repository.viewer::advanceHotp,
+                                    repository.viewer::tickOtp
+                                )
+                            }
+                                ?: Text(stringResource(R.string.totp_unavailable))
+                            TextButton(onClick = repository.viewer::lock) {
+                                Text(stringResource(R.string.password_lock))
+                            }
+                            entry.notice?.let { Text(it) }
+                        }
+                    }
+                }
+            }
+        }
+    }
+    if (manual) {
+        PassphraseDialog(
+            stringResource(R.string.auth_manual),
+            stringResource(R.string.auth_manual_detail),
+            presentation = authentication.presentation,
+            onCancel = {
+                manual = false
+                repository.cancel()
+                authentication.cancel()
+            },
+            onSubmit = {
+                manual = false
+                requested = true
+                if (discovery) repository.discover(it) else repository.viewer.unlock(it)
+            }
+        )
+    }
+}

android/features/src/main/res/values/strings.xml

@@ -235,4 +235,22 @@
     <string name="qr_export_private_confirm">I checked this fingerprint and authorize displaying its private QR codes.</string>
     <string name="qr_animate">Automatically advance frames</string>
     <string name="qr_setup_import">Prepare the scanned key</string>
+    <string name="otp_hotp">HOTP</string>
+    <string name="otp_waiting">Waiting for a current code.</string>
+    <string name="otp_hotp_pending">Generate a code to consume the next HOTP counter.</string>
+    <string name="otp_refresh">Refresh code</string>
+    <string name="otp_generate_hotp">Generate next HOTP code</string>
+    <string name="otp_confirm_hotp">This consumes counter %1$s and saves the incremented counter in the encrypted entry. Continue?</string>
+    <string name="otp_counter">Generated for counter %1$s</string>
+    <plurals name="otp_countdown">
+        <item quantity="one">%1$s second remaining</item>
+        <item quantity="other">%1$s seconds remaining</item>
+    </plurals>
+    <string name="totp_refresh_catalog">Refresh TOTP catalog</string>
+    <string name="totp_needs_catalog">Refresh the catalog after unlocking to find TOTP entries.</string>
+    <string name="totp_empty">No TOTP entries found.</string>
+    <string name="totp_choose">Choose a TOTP entry.</string>
+    <string name="totp_unavailable">This entry no longer has a TOTP code.</string>
+    <string name="totp_stale">This entry changed. Refresh the catalog and select it again.</string>
+    <string name="totp_back">Back to TOTP entries</string>
 </resources>

crates/mobile-bridge/src/lib.rs

@@ -1247,6 +1247,61 @@ pub struct MobileTotpDetail {
     pub watch: MobileWatchSnapshotStatus,
 }
 
+#[derive(Clone, Copy, uniffi::Enum)]
+pub enum MobileOtpCodeKind {
+    Totp,
+    Hotp,
+}
+
+#[derive(Clone, uniffi::Record)]
+pub struct MobileOtpCodePresentation {
+    pub document_revision: String,
+    pub kind: MobileOtpCodeKind,
+    pub issuer: Option<String>,
+    pub account: String,
+    pub code: Option<String>,
+    pub grouped_code: Option<String>,
+    pub period: Option<u64>,
+    pub valid_until: Option<u64>,
+    pub remaining_seconds: Option<u64>,
+    pub counter: Option<u64>,
+    pub next_counter: Option<u64>,
+}
+
+impl From<ironstorage::mobile_totp::MobileOtpCodePresentation> for MobileOtpCodePresentation {
+    fn from(value: ironstorage::mobile_totp::MobileOtpCodePresentation) -> Self {
+        let text = |bytes: ironstorage::repository::SecretBytes| {
+            String::from_utf8(bytes.expose().to_vec())
+                .expect("storage-generated OTP codes are ASCII")
+        };
+        Self {
+            document_revision: value.document_revision,
+            kind: match value.kind {
+                ironstorage::otp::OtpKind::Totp => MobileOtpCodeKind::Totp,
+                ironstorage::otp::OtpKind::Hotp => MobileOtpCodeKind::Hotp,
+            },
+            issuer: value.issuer,
+            account: value.account,
+            code: value.code.map(text),
+            grouped_code: value.grouped_code.map(text),
+            period: value.period,
+            valid_until: value.valid_until,
+            remaining_seconds: value.remaining_seconds,
+            counter: value.counter,
+            next_counter: value.next_counter,
+        }
+    }
+}
+
+#[uniffi::export]
+pub fn mobile_otp_window_current(valid_until: u64, period: u64, unix_seconds: u64) -> bool {
+    ironstorage::otp::OtpCodeValidity::Timed {
+        valid_until,
+        period,
+    }
+    .is_current(unix_seconds)
+}
+
 impl From<StorageTotpDetail> for MobileTotpDetail {
     fn from(detail: StorageTotpDetail) -> Self {
         Self {
@@ -2010,6 +2065,44 @@ impl MobileAuthentication {
             .map_err(Into::into)
     }
 
+    pub fn presented_otp_code(
+        &self,
+        path: String,
+        revision: String,
+        unix_seconds: u64,
+        consumed_counter: Option<u64>,
+    ) -> Result<Option<MobileOtpCodePresentation>, MobileAuthenticationFfiError> {
+        self.authentication
+            .presented_otp_code(&path, &revision, unix_seconds, consumed_counter)
+            .map(|value| value.map(Into::into))
+            .map_err(Into::into)
+    }
+
+    pub fn copy_presented_otp_code(
+        &self,
+        path: String,
+        revision: String,
+        unix_seconds: u64,
+        consumed_counter: Option<u64>,
+    ) -> Result<MobileEntryCopy, MobileAuthenticationFfiError> {
+        self.authentication
+            .copy_presented_otp_code(&path, &revision, unix_seconds, consumed_counter)
+            .map(Into::into)
+            .map_err(Into::into)
+    }
+
+    pub fn advance_presented_hotp(
+        &self,
+        path: String,
+        revision: String,
+        confirmed: bool,
+    ) -> Result<MobileOtpCodePresentation, MobileAuthenticationFfiError> {
+        self.authentication
+            .advance_presented_hotp(&path, &revision, confirmed)
+            .map(Into::into)
+            .map_err(Into::into)
+    }
+
     pub fn prepare_presented_entry_mutation(
         &self,
         path: String,
@@ -2146,6 +2239,16 @@ impl MobileAuthentication {
             .map_err(Into::into)
     }
 
+    pub fn cached_totp_navigation(
+        &self,
+    ) -> Result<Option<Vec<password_navigation::MobileNavigationRow>>, MobileAuthenticationFfiError>
+    {
+        self.authentication
+            .cached_totp_navigation()
+            .map(|rows| rows.map(|rows| rows.into_iter().map(Into::into).collect()))
+            .map_err(Into::into)
+    }
+
     pub fn search_cached_totp_page(
         &self,
         query: String,

crates/storage/src/mobile_authentication.rs

@@ -30,13 +30,14 @@ use crate::{
         MobileMutationRequest, MobileMutationService,
     },
     mobile_totp::{
-        MobileTotpDetail, MobileTotpError, MobileTotpOperation, MobileTotpPage, MobileTotpService,
+        MobileOtpCodePresentation, MobileTotpDetail, MobileTotpError, MobileTotpOperation,
+        MobileTotpPage, MobileTotpService, otp_code_presentation,
     },
     mobile_watch::{
         MobileWatchSnapshotState, MobileWatchSnapshotStatus, WatchSnapshotError,
         WatchSnapshotSender, WatchSnapshotTransfer,
     },
-    otp::OtpError,
+    otp::{OtpError, OtpKind, OtpService},
     recipient::RecipientPolicyManager,
     repository::{
         DirectoryPath, EncryptedEntry, EntryPath, Repository, RepositoryError, SecretBytes,
@@ -1124,6 +1125,121 @@ impl MobileAuthentication {
         })
     }
 
+    pub fn presented_otp_code(
+        &self,
+        path: &str,
+        revision: &str,
+        unix_seconds: u64,
+        consumed_counter: Option<u64>,
+    ) -> Result<Option<MobileOtpCodePresentation>, MobileAuthenticationError> {
+        self.ensure_repository_idle()?;
+        let document = self.open_presented_document(path, revision)?;
+        match otp_code_presentation(&document, unix_seconds, consumed_counter) {
+            Err(OtpError::ConcurrentModification { .. }) => {
+                self.manual_lock()?;
+                Err(MobileAuthenticationError::new(
+                    MobileAuthenticationErrorKind::Conflict,
+                    "HOTP Entry Changed",
+                    "Refresh and unlock the entry before using its code.",
+                ))
+            }
+            result => result.map_err(|error| totp_error(error.into())),
+        }
+    }
+
+    pub fn copy_presented_otp_code(
+        &self,
+        path: &str,
+        revision: &str,
+        unix_seconds: u64,
+        consumed_counter: Option<u64>,
+    ) -> Result<MobileEntryCopy, MobileAuthenticationError> {
+        let code = self
+            .presented_otp_code(path, revision, unix_seconds, consumed_counter)?
+            .and_then(|value| value.code)
+            .ok_or_else(|| {
+                entry_detail(
+                    "OTP Code Is Unavailable",
+                    "Open a TOTP code or explicitly generate a HOTP code before copying.",
+                )
+            })?;
+        Ok(MobileEntryCopy {
+            value: String::from_utf8(code.expose().to_vec())
+                .map_err(|_| entry_detail("OTP Code Is Unavailable", "The code is not UTF-8."))?,
+            timeout_seconds: self.config.clipboard_timeout().duration().as_secs(),
+        })
+    }
+
+    pub fn advance_presented_hotp(
+        &self,
+        path: &str,
+        revision: &str,
+        confirmed: bool,
+    ) -> Result<MobileOtpCodePresentation, MobileAuthenticationError> {
+        if !confirmed {
+            return Err(MobileAuthenticationError::new(
+                MobileAuthenticationErrorKind::Cancelled,
+                "HOTP Generation Cancelled",
+                "The HOTP counter was not changed.",
+            ));
+        }
+        self.ensure_repository_idle()?;
+        self.ensure_active()?;
+        self.reserve_entry_mutation()?;
+        let result = (|| {
+            let document = self.open_presented_document(path, revision)?;
+            if self.editor_state(path)?.0 {
+                return Err(entry_detail(
+                    "HOTP Entry Is Being Edited",
+                    "Close the entry editor before generating a code.",
+                ));
+            }
+            if document
+                .otp_uri()
+                .map_err(|error| totp_error(error.into()))?
+                .is_none_or(|uri| uri.kind() != OtpKind::Hotp)
+            {
+                return Err(totp_error(OtpError::NotHotp.into()));
+            }
+            let (handle, key, identity) = {
+                let status = self.status()?;
+                let active = status.active.as_ref().ok_or_else(locked_error)?;
+                (
+                    active.handle.clone(),
+                    active.key.clone(),
+                    status.git_identity.clone(),
+                )
+            };
+            let mut provider = KeyOnlyProvider::new(handle, &key);
+            let mut committer =
+                AutomaticEntryCommitter::for_entry(&self.repository, path, identity)
+                    .map_err(|error| entry_detail("HOTP Counter Could Not Be Updated", error))?;
+            let outcome = OtpService::new(&self.repository, &self.keys)
+                .code_for_document(&document, &mut provider, &mut committer)
+                .map_err(|error| totp_error(error.into()))?;
+            let committed_error = || {
+                entry_detail(
+                    "HOTP Counter Was Updated",
+                    "Refresh and unlock the entry before generating another code. The previous counter was already consumed.",
+                )
+            };
+            let updated = self
+                .open_active_document(path)
+                .map_err(|_| committed_error())?;
+            let code = otp_code_presentation(&updated, 0, outcome.counter())
+                .map_err(|_| committed_error())?
+                .ok_or_else(committed_error)?;
+            if code.code.as_ref().map(SecretBytes::expose) != Some(outcome.code().expose()) {
+                self.manual_lock()?;
+                return Err(committed_error());
+            }
+            self.reconcile_saved_document(&updated);
+            Ok(code)
+        })();
+        self.release_entry_mutation();
+        result
+    }
+
     pub fn prepare_presented_entry_mutation(
         &self,
         path: &str,
@@ -1283,6 +1399,29 @@ impl MobileAuthentication {
         self.search_cached_totp_page("")
     }
 
+    pub fn cached_totp_navigation(
+        &self,
+    ) -> Result<
+        Option<Vec<crate::mobile_passwords::navigation::NavigationRow>>,
+        MobileAuthenticationError,
+    > {
+        self.cached_totp_page()?
+            .map(|page| {
+                page.rows()
+                    .iter()
+                    .map(|row| {
+                        let path = EntryPath::parse(row.path()).map_err(entry_error)?;
+                        crate::mobile_passwords::navigation::entry_navigation_row(
+                            &self.repository,
+                            &path,
+                        )
+                        .map_err(|error| entry_detail(error.title(), error.detail()))
+                    })
+                    .collect()
+            })
+            .transpose()
+    }
+
     pub fn search_cached_totp_page(
         &self,
         query: &str,
@@ -2452,6 +2591,310 @@ mod tests {
         watch_preference,
     };
 
+    struct OtpClock(std::sync::atomic::AtomicU64);
+    impl crate::authentication::AuthenticationClock for OtpClock {
+        fn now(&self) -> std::time::Duration {
+            std::time::Duration::from_secs(self.0.load(std::sync::atomic::Ordering::Relaxed))
+        }
+    }
+
+    fn otp_fixture(
+        uri: &str,
+    ) -> (
+        tempfile::TempDir,
+        std::sync::Arc<super::MobileAuthentication>,
+        std::sync::Arc<OtpClock>,
+    ) {
+        use crate::{
+            crypto::KeyStore,
+            git::{GitIdentity, GitRepository},
+            recipient::RecipientPolicyManager,
+            repository::{EntryPath, Repository, SecretBytes},
+        };
+        let (root, private, backend) = crate::mobile_onboarding::android::tests::home_fixture();
+        let config = private.configuration().unwrap().unwrap();
+        let repository = Repository::open(config.vault()).unwrap();
+        let keys = KeyStore::load(config.key_material()).unwrap();
+        let path = EntryPath::parse("otp").unwrap();
+        let policy = RecipientPolicyManager::new(&repository, &keys)
+            .resolve_for_entry(&path, None)
+            .unwrap();
+        let encrypted = keys
+            .encrypt(
+                SecretBytes::new(format!("fixture-password\n{uri}\n").into_bytes()),
+                policy.recipients(),
+            )
+            .unwrap();
+        repository.write_entry(&path, &encrypted).unwrap();
+        GitRepository::open(&repository, GitIdentity::ironstorage())
+            .unwrap()
+            .commit_all("Seed encrypted OTP fixture")
+            .unwrap();
+        let clock = std::sync::Arc::new(OtpClock(std::sync::atomic::AtomicU64::new(0)));
+        let authentication = private.authentication(backend, clock.clone()).unwrap();
+        (root, authentication, clock)
+    }
+
+    #[test]
+    fn otp_presentation_matches_rfc_vectors_and_boundaries_without_renewing_the_lease() {
+        use crate::{otp::OtpCodeValidity, repository::SecretBytes};
+        for (algorithm, secret, expected) in [
+            ("SHA1", "12345678901234567890", "94287082"),
+            ("SHA256", "12345678901234567890123456789012", "46119246"),
+            (
+                "SHA512",
+                "1234567890123456789012345678901234567890123456789012345678901234",
+                "90693936",
+            ),
+        ] {
+            let secret = data_encoding::BASE32_NOPAD.encode(secret.as_bytes());
+            let uri = format!(
+                "otpauth://totp/RFC:alice?secret={secret}&algorithm={algorithm}&digits=8&period=30&issuer=RFC"
+            );
+            let (_root, authentication, clock) = otp_fixture(&uri);
+            assert!(authentication.cached_totp_navigation().unwrap().is_none());
+            authentication
+                .unlock_entry(
+                    "otp",
+                    Some(SecretBytes::new(b"fixture-alice-passphrase".to_vec())),
+                )
+                .unwrap();
+            authentication.set_authentication_timeout_text("2").unwrap();
+            let page = authentication.entry_page("otp", 59).unwrap();
+            let revision = page.page().revision();
+            let code = authentication
+                .presented_otp_code("otp", revision, 59, None)
+                .unwrap()
+                .unwrap();
+            assert_eq!(code.code.as_ref().unwrap().expose(), expected.as_bytes());
+            assert_eq!(
+                code.grouped_code.as_ref().unwrap().expose(),
+                format!("{} {}", &expected[..4], &expected[4..]).as_bytes()
+            );
+            assert_eq!(code.remaining_seconds, Some(1));
+            assert_eq!(code.valid_until, Some(60));
+            let rows = authentication.cached_totp_navigation().unwrap().unwrap();
+            assert_eq!(rows.len(), 1);
+            let cached = std::fs::read(
+                authentication
+                    .config
+                    .source()
+                    .with_file_name("totp-catalog.toml"),
+            )
+            .unwrap();
+            let at_boundary = authentication
+                .presented_otp_code("otp", revision, 60, None)
+                .unwrap()
+                .unwrap();
+            assert_ne!(
+                at_boundary.code.as_ref().unwrap().expose(),
+                expected.as_bytes()
+            );
+            assert_eq!(at_boundary.remaining_seconds, Some(30));
+            assert_eq!(at_boundary.valid_until, Some(90));
+            assert_eq!(
+                std::fs::read(
+                    authentication
+                        .config
+                        .source()
+                        .with_file_name("totp-catalog.toml")
+                )
+                .unwrap(),
+                cached
+            );
+            let window = OtpCodeValidity::Timed {
+                valid_until: 60,
+                period: 30,
+            };
+            assert!(!window.is_current(29));
+            assert!(window.is_current(30));
+            assert!(window.is_current(59));
+            assert!(!window.is_current(60));
+            clock.0.store(1, std::sync::atomic::Ordering::Relaxed);
+            authentication
+                .presented_otp_code("otp", revision, 61, None)
+                .unwrap();
+            assert_eq!(authentication.state().unwrap().remaining_seconds(), 1);
+            clock.0.store(2, std::sync::atomic::Ordering::Relaxed);
+            assert!(
+                authentication
+                    .presented_otp_code("otp", revision, 62, None)
+                    .is_err()
+            );
+            assert!(!authentication.state().unwrap().unlocked());
+        }
+    }
+
+    #[test]
+    fn malformed_otp_keeps_the_structured_entry_readable() {
+        use crate::repository::SecretBytes;
+        let (_root, authentication, _) = otp_fixture("otpauth://totp/Invalid?secret=!");
+        authentication
+            .unlock_entry(
+                "otp",
+                Some(SecretBytes::new(b"fixture-alice-passphrase".to_vec())),
+            )
+            .unwrap();
+        let page = authentication.entry_page("otp", 59).unwrap();
+        assert!(!page.page().sections().is_empty());
+        assert!(
+            authentication
+                .presented_otp_code("otp", page.page().revision(), 59, None)
+                .unwrap()
+                .is_none()
+        );
+    }
+
+    #[test]
+    fn hotp_requires_confirmation_commits_once_and_copy_refresh_never_advance() {
+        use crate::repository::SecretBytes;
+        let (_root, authentication, _) = otp_fixture(
+            "otpauth://hotp/RFC:alice?secret=GEZDGNBVGY3TQOJQGEZDGNBVGY3TQOJQ&counter=0&issuer=RFC",
+        );
+        authentication
+            .unlock_entry(
+                "otp",
+                Some(SecretBytes::new(b"fixture-alice-passphrase".to_vec())),
+            )
+            .unwrap();
+        let page = authentication.entry_page("otp", 0).unwrap();
+        let revision = page.page().revision();
+        let before = authentication
+            .repository
+            .read_entry(&crate::repository::EntryPath::parse("otp").unwrap())
+            .unwrap();
+        assert!(
+            authentication
+                .advance_presented_hotp("otp", revision, false)
+                .is_err()
+        );
+        assert_eq!(
+            authentication
+                .repository
+                .read_entry(&crate::repository::EntryPath::parse("otp").unwrap())
+                .unwrap(),
+            before
+        );
+        assert!(
+            authentication
+                .presented_otp_code("otp", revision, 0, None)
+                .unwrap()
+                .unwrap()
+                .code
+                .is_none()
+        );
+        assert!(
+            authentication
+                .copy_presented_otp_code("otp", revision, 0, None)
+                .is_err()
+        );
+        let issued = authentication
+            .advance_presented_hotp("otp", revision, true)
+            .unwrap();
+        assert_eq!(issued.code.as_ref().unwrap().expose(), b"287082");
+        assert_eq!(issued.counter, Some(1));
+        assert_eq!(issued.next_counter, Some(2));
+        assert_eq!(
+            authentication
+                .copy_presented_otp_code("otp", &issued.document_revision, 100, issued.counter)
+                .unwrap()
+                .value(),
+            "287082"
+        );
+        let refreshed = authentication
+            .presented_otp_code("otp", &issued.document_revision, 200, issued.counter)
+            .unwrap()
+            .unwrap();
+        assert_eq!(refreshed.next_counter, Some(2));
+        let next = authentication
+            .advance_presented_hotp("otp", &issued.document_revision, true)
+            .unwrap();
+        assert_eq!(next.code.as_ref().unwrap().expose(), b"359152");
+        assert_eq!(next.next_counter, Some(3));
+        assert!(
+            authentication
+                .copy_presented_otp_code("otp", &next.document_revision, 201, issued.counter)
+                .is_err()
+        );
+        authentication.manual_lock().unwrap();
+        assert!(
+            authentication
+                .copy_presented_otp_code("otp", &next.document_revision, 202, next.counter)
+                .is_err()
+        );
+    }
+
+    #[test]
+    fn hotp_commit_failure_and_overflow_leave_the_ciphertext_unchanged() {
+        use crate::repository::{EntryPath, SecretBytes};
+        for counter in ["0", "18446744073709551615"] {
+            let (_root, authentication, _) = otp_fixture(&format!(
+                "otpauth://hotp/RFC:alice?secret=GEZDGNBVGY3TQOJQGEZDGNBVGY3TQOJQ&counter={counter}"
+            ));
+            authentication
+                .unlock_entry(
+                    "otp",
+                    Some(SecretBytes::new(b"fixture-alice-passphrase".to_vec())),
+                )
+                .unwrap();
+            let path = EntryPath::parse("otp").unwrap();
+            let before = authentication.repository.read_entry(&path).unwrap();
+            let page = authentication.entry_page("otp", 0).unwrap();
+            if counter == "0" {
+                std::fs::write(
+                    authentication
+                        .repository
+                        .root_path()
+                        .join(".git/index.lock"),
+                    b"locked",
+                )
+                .unwrap();
+            }
+            assert!(
+                authentication
+                    .advance_presented_hotp("otp", page.page().revision(), true)
+                    .is_err()
+            );
+            assert_eq!(authentication.repository.read_entry(&path).unwrap(), before);
+        }
+    }
+
+    #[test]
+    fn custom_period_and_stale_revision_are_storage_owned() {
+        use crate::repository::SecretBytes;
+        let (_root, authentication, _) = otp_fixture(
+            "otpauth://totp/Custom:alice?secret=JBSWY3DPEHPK3PXP&algorithm=SHA256&digits=6&period=60&issuer=Custom",
+        );
+        authentication
+            .unlock_entry(
+                "otp",
+                Some(SecretBytes::new(b"fixture-alice-passphrase".to_vec())),
+            )
+            .unwrap();
+        let page = authentication.entry_page("otp", 59).unwrap();
+        let code = authentication
+            .presented_otp_code("otp", page.page().revision(), 59, None)
+            .unwrap()
+            .unwrap();
+        assert_eq!(code.period, Some(60));
+        assert_eq!(code.valid_until, Some(60));
+        assert_eq!(code.remaining_seconds, Some(1));
+        assert_eq!(code.code.as_ref().unwrap().expose().len(), 6);
+        assert_eq!(code.grouped_code.as_ref().unwrap().expose().len(), 7);
+        let next = authentication
+            .presented_otp_code("otp", page.page().revision(), 60, None)
+            .unwrap()
+            .unwrap();
+        assert_eq!(next.valid_until, Some(120));
+        assert_eq!(next.remaining_seconds, Some(60));
+        assert!(
+            authentication
+                .presented_otp_code("otp", "stale", 60, None)
+                .is_err()
+        );
+        assert!(!authentication.state().unwrap().unlocked());
+    }
+
     #[test]
     fn explicit_biometric_enrollment_and_restore_work_without_a_password_entry() {
         use crate::authentication::SystemAuthenticationClock;

crates/storage/src/mobile_passwords/navigation.rs

@@ -5,8 +5,22 @@ use super::{
 };
 use crate::{
     mobile_private_storage::{PrivateStorage, exclusive_lock},
-    repository::{DirectoryPath, Repository},
+    repository::{DirectoryPath, EntryPath, Repository},
 };
+
+pub(crate) fn entry_navigation_row(
+    repository: &Repository,
+    path: &EntryPath,
+) -> Result<NavigationRow, MobilePasswordError> {
+    let row = super::search_row(path, &path.to_string());
+    let revision = repository
+        .navigation_revision(path.as_path(), true)
+        .map_err(MobilePasswordError::repository)?;
+    Ok(NavigationRow {
+        row,
+        revision: HEXLOWER.encode(&Sha256::digest(revision.as_bytes())),
+    })
+}
 use cap_std::{ambient_authority, fs::Dir};
 use data_encoding::HEXLOWER;
 use sha2::{Digest, Sha256};

crates/storage/src/mobile_totp.rs

@@ -204,6 +204,90 @@ pub struct MobileTotpDetail {
     watch: MobileWatchSnapshotStatus,
 }
 
+pub struct MobileOtpCodePresentation {
+    pub document_revision: String,
+    pub kind: OtpKind,
+    pub issuer: Option<String>,
+    pub account: String,
+    pub code: Option<SecretBytes>,
+    pub grouped_code: Option<SecretBytes>,
+    pub period: Option<u64>,
+    pub valid_until: Option<u64>,
+    pub remaining_seconds: Option<u64>,
+    pub counter: Option<u64>,
+    pub next_counter: Option<u64>,
+}
+
+impl fmt::Debug for MobileOtpCodePresentation {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.write_str("MobileOtpCodePresentation([REDACTED])")
+    }
+}
+
+pub(crate) fn otp_code_presentation(
+    document: &EntryDocument,
+    unix_seconds: u64,
+    consumed_counter: Option<u64>,
+) -> Result<Option<MobileOtpCodePresentation>, OtpError> {
+    let Some(uri) = document.otp_uri().ok().flatten() else {
+        return Ok(None);
+    };
+    let (code, remaining_seconds, counter, valid_until) = match uri.kind() {
+        OtpKind::Totp => {
+            if consumed_counter.is_some() {
+                return Err(OtpError::UnexpectedCounter);
+            }
+            let period = uri.period().ok_or(OtpError::NotTotp)?;
+            let end = (unix_seconds / period)
+                .checked_add(1)
+                .and_then(|step| step.checked_mul(period))
+                .ok_or(OtpError::CounterOverflow)?;
+            (
+                Some(uri.code_at(unix_seconds)?),
+                Some(end - unix_seconds),
+                None,
+                Some(end),
+            )
+        }
+        OtpKind::Hotp => {
+            let next = uri.counter().ok_or(OtpError::MissingCounter)?;
+            let code = if let Some(consumed) = consumed_counter {
+                if consumed != next {
+                    return Err(OtpError::ConcurrentModification {
+                        entry: document.path().clone(),
+                    });
+                }
+                Some(uri.code_for_counter(consumed)?)
+            } else {
+                None
+            };
+            (code, None, consumed_counter, None)
+        }
+    };
+    let grouped_code = code.as_ref().map(|code| {
+        let bytes = code.expose();
+        let middle = bytes.len() / 2;
+        let mut grouped = Vec::with_capacity(bytes.len() + 1);
+        grouped.extend_from_slice(&bytes[..middle]);
+        grouped.push(b' ');
+        grouped.extend_from_slice(&bytes[middle..]);
+        SecretBytes::new(grouped)
+    });
+    Ok(Some(MobileOtpCodePresentation {
+        document_revision: crate::mobile_entry::document_revision(document),
+        kind: uri.kind(),
+        issuer: uri.issuer().map(str::to_owned),
+        account: uri.account().to_owned(),
+        code,
+        grouped_code,
+        period: uri.period(),
+        valid_until,
+        remaining_seconds,
+        counter,
+        next_counter: uri.counter().and_then(|counter| counter.checked_add(1)),
+    }))
+}
+
 impl MobileTotpDetail {
     pub fn path(&self) -> &str {
         &self.path

crates/storage/src/otp.rs

@@ -426,6 +426,21 @@ pub enum OtpCodeValidity {
 }
 
 impl OtpCodeValidity {
+    pub fn is_current(self, unix_seconds: u64) -> bool {
+        match self {
+            Self::Timed {
+                valid_until,
+                period,
+            } => {
+                period > 0
+                    && valid_until
+                        .checked_sub(period)
+                        .is_some_and(|start| start <= unix_seconds && unix_seconds < valid_until)
+            }
+            Self::CounterBased { .. } => true,
+        }
+    }
+
     pub fn valid_until(self) -> Option<u64> {
         match self {
             Self::Timed { valid_until, .. } => Some(valid_until),
@@ -678,6 +693,23 @@ impl<'a> OtpService<'a> {
         )
     }
 
+    pub(crate) fn code_for_document(
+        &self,
+        document: &crate::document::EntryDocument,
+        provider: &mut impl SecretProvider,
+        committer: &mut impl EntryCommitter,
+    ) -> Result<OtpCodeOutcome, OtpError> {
+        let (path, original, plaintext, range, uri) =
+            self.load_code_entry(&document.path().to_string(), provider)?;
+        if document.original_ciphertext() != Some(&original) {
+            return Err(OtpError::ConcurrentModification { entry: path });
+        }
+        if uri.kind() != OtpKind::Hotp {
+            return Err(OtpError::NotHotp);
+        }
+        self.finish_code(path, original, plaintext, range, uri, 0, None, committer)
+    }
+
     /// Generate a code with storage-owned lazy Git selection. TOTP is
     /// read-only and never opens Git; HOTP opens the innermost repository only
     /// after the token has been decrypted and identified as counter based.

docs/android/otp.md

@@ -0,0 +1,49 @@
+# Android one-time passwords
+
+Issue [#107](https://git.rfc1437.de/hugo/IronStorage/issues/107) connects the TOTP
+destination to the storage-owned discovery catalog. Opening the list reads cached
+metadata without decrypting entries. Select a row, then Unlock to display its
+issuer, account, grouped code, countdown and progress. Refresh TOTP catalog is an
+explicit authenticated discovery action; the progress/search workflow belongs
+to [#110](https://git.rfc1437.de/hugo/IronStorage/issues/110).
+
+The normal entry viewer and TOTP detail use the same code component and native
+viewer controller. Decryption, creation and editing reconcile the catalog in
+Rust. Only nonsecret row identities and revisions are restored after recreation.
+OTP parameters, codes and authentication secrets are never persisted by Kotlin.
+
+Rust computes SHA1/SHA256/SHA512 codes, six/eight digits, custom periods, absolute
+validity boundaries, grouping and countdown. The composed code component owns a
+STARTED-lifecycle coroutine that submits OS clock facts without touching the
+authentication lease. Scrolling it out or leaving stops decryption/countdown ticks;
+an expiry-only native window check still erases held codes when hidden. Rust validates each
+returned window before publication, including delayed results and backward clock
+changes. Lock, background, expiry, entry changes and stale revisions remove codes
+and cancel presentation. Explicit copies use the existing sensitive clipboard
+adapter and Rust timeout/ownership checks.
+
+HOTP in the normal entry viewer requires Generate next HOTP code and a separate
+counter confirmation. The existing pass-otp core increments and atomically commits
+the encrypted counter before returning its code. Refresh and Copy use that same
+committed counter without incrementing. Stale documents, open editors, failed Git
+commits and overflow cannot consume a counter. The TOTP discovery catalog remains
+specific to time-based entries. Android exposes no Watch sharing controls.
+
+## Validation
+
+Rust tests cover RFC 6238 algorithm vectors, six/eight digits, 30/60-second
+boundaries, cache agreement, polling without lease renewal, malformed URI
+diagnostics, stale revision revocation, HOTP confirmation, copy/refresh stability,
+commit rollback and counter overflow. Android's NativeOtpPresentationTest uses
+real encrypted stores with fake wall/lease clocks to verify catalog-only reads,
+boundary transitions, tick lease expiry, clipboard handoff expiry, queued user
+actions overtaking read-only observations, both HOTP generations and background
+revocation. TotpScreenTest covers explicit unlock, grouped code/countdown/copy,
+lock cleanup, HOTP confirm/cancel, tick cancellation on leaving and 300% text
+without clipped digits. Computer use inspects the same Compose
+components on an ARM64 emulator using disposable presentation fixtures.
+
+All emulator installs preserve the retained app container. Production Keystore
+and biometric enrollment are unchanged by this story; the native controller tests
+provide deterministic OS capability callbacks. Supported release ABIs remain
+arm64-v8a and armeabi-v7a; physical devices and x86_64 are outside this milestone.

docs/android/parity.md

@@ -31,7 +31,7 @@ Every issue linked here belongs to milestone 23.
 | OTP URI input, camera/image import, review before Save (OtpImportViewController; TOTP Add action) | mobile_entry::MobileEntryDraft::add_otp_image; document/otp/presentation | CameraX frames or Android photo picker bytes; Rust decode and field construction | #103/#106/#107; URI/image/scan parity, invalid/oversized input, cancel; no payload parsing in Kotlin |
 | Move/copy/delete entries and folders, destination browse, overwrite and dirty-editor handling (PasswordMutationCoordinator) | mobile_mutation::MobileMutationService/Plan/Request; mutation | Compose dialogs/destination picker | #108; revisions, destination conflicts, recipient reencryption and rollback |
 | TOTP discovery catalog, incremental progress, warm cache, refresh, cancel/resume, cached search (TotpListViewController) | mobile_totp discovery/catalog/operation; mobile_authentication cached/search APIs | Compose list/progress/search; private no-backup catalog | #90/#110; cold/warm/change/add/remove/corrupt/wrong-store/concurrent-change tests |
-| TOTP rows, large detail code, countdown/expiry, copying (TotpDetailViewController, TotpCodeView) | mobile_totp::MobileTotpPage/Detail; otp; mobile_authentication::{totp_detail,copy_totp_code} | Compose code/detail; OS clock facts, Rust timing | #107/#100; RFC vectors, boundary countdown, stale callback/relock and clipboard |
+| TOTP rows, large detail code, countdown/expiry, copying (TotpDetailViewController, TotpCodeView) | mobile_totp::MobileOtpCodePresentation; otp; mobile_authentication::{presented_otp_code,copy_presented_otp_code,advance_presented_hotp} | Compose code/detail; OS clock facts, Rust timing | #107/#100; [OTP behavior and evidence](otp.md), RFC vectors, boundary countdown, stale callback/relock and clipboard |
 | Repository/server identity, local-only/add-remote Settings, token replace/remove (PreferencesViewController, TokenUpdateViewController) | mobile_authentication::MobilePreferences; mobile_onboarding::replace_configured_application_token; config/secret_store | Compose Settings/facade | #104/#95; no token display; protected replacement/removal and offline operation |
 | Key identity/fingerprint, GPG recovery import and public/private QR export (KeyImportScannerViewController, KeyExportListViewController, KeyQrExportViewController) | mobile_key_transfer::{MobileKeyTransferService,MobileKeyTransferImport}; crypto/presentation | CameraX Preview/ImageAnalysis; animated Rust-provided matrices | #106/#104; multi-frame order/duplicates/interruption, bounded frames, private export authorization and camera denial |
 | Inactivity timeout, biometric enable/disable, Lock Now, appearance and Git commit name/email | mobile_authentication preference setters, git_identity; config | Compose Settings, BiometricPrompt, system/light/dark theme | #98/#104; persistent settings, validation, Keystore enrollment/recovery and lease revocation |