VaultAdoptSnapshotTest.kt

1package com.peachpasswords.sync23import kotlinx.coroutines.channels.Channel4import kotlinx.coroutines.runBlocking5import org.junit.Assert.assertEquals6import org.junit.Assert.assertNull7import org.junit.Assert.assertTrue8import org.junit.Test910/**11 * Inline vault snapshot protocol parity with the browser12 * `vault-adopt-snapshot.test.ts`. Round-trip, chunking, and validation13 * tests for the ADOPT_SNAPSHOT / ADOPT_SNAPSHOT_APPLIED frames.14 */15class VaultAdoptSnapshotTest {1617    private fun memoryPair(): Pair<PairingTransport, PairingTransport> {18        val a2b = Channel<ByteArray>(Channel.UNLIMITED)19        val b2a = Channel<ByteArray>(Channel.UNLIMITED)20        val a = object : PairingTransport {21            override suspend fun send(msg: ByteArray) { a2b.send(msg) }22            override suspend fun receive(): ByteArray = b2a.receive()23            override suspend fun close() {}24        }25        val b = object : PairingTransport {26            override suspend fun send(msg: ByteArray) { b2a.send(msg) }27            override suspend fun receive(): ByteArray = a2b.receive()28            override suspend fun close() {}29        }30        return a to b31    }3233    @Test34    fun `round-trips an empty vault`() = runBlocking {35        val (source, receiver) = memoryPair()36        sendVaultSnapshot(source, emptyMap(), emptyMap())37        val (entries, tombstones) = receiveVaultSnapshot(receiver)38        assertTrue(entries.isEmpty())39        assertTrue(tombstones.isEmpty())40    }4142    @Test43    fun `round-trips 50 entries and 5 tombstones in a single chunk`() = runBlocking {44        val (source, receiver) = memoryPair()45        val entries = (0 until 50).associate { "id-$it" to "cipher-$it" }46        val tombstones = (0 until 5).associate { "dead-$it" to (1000L + it) }47        sendVaultSnapshot(source, entries, tombstones)48        val (receivedEntries, receivedTombstones) = receiveVaultSnapshot(receiver)49        assertEquals(entries, receivedEntries)50        assertEquals(tombstones, receivedTombstones)51    }5253    @Test54    fun `splits a large vault into 3+ chunks and reassembles`() = runBlocking {55        val (source, receiver) = memoryPair()56        var frames = 057        val countingSource = object : PairingTransport {58            override suspend fun send(msg: ByteArray) { frames++; source.send(msg) }59            override suspend fun receive(): ByteArray = source.receive()60            override suspend fun close() {}61        }62        val big = "x".repeat(200 * 1024)63        val entries = (0 until 5).associate { "id-$it" to big }64        val tombstones = mapOf("dead-0" to 42L)65        sendVaultSnapshot(countingSource, entries, tombstones)66        val (receivedEntries, receivedTombstones) = receiveVaultSnapshot(receiver)67        assertTrue("expected 3+ chunks, got $frames", frames >= 3)68        assertEquals(entries, receivedEntries)69        assertEquals(tombstones, receivedTombstones)70    }7172    @Test73    fun `rejects out-of-order chunks`() = runBlocking {74        val (source, receiver) = memoryPair()75        sendFrame(source, AdoptionFrame.Snapshot(76            chunkIndex = 1,77            chunkCount = 2,78            entries = mapOf("a" to "x"),79            tombstones = emptyMap(),80        ))81        val error = runCatching { receiveVaultSnapshot(receiver) }.exceptionOrNull()82        assertTrue(error is IllegalStateException)83        assertTrue(error!!.message!!.contains("OUT_OF_ORDER"))84    }8586    @Test87    fun `rejects chunk_count exceeding MAX_SNAPSHOT_CHUNKS`() = runBlocking {88        val (source, receiver) = memoryPair()89        sendFrame(source, AdoptionFrame.Snapshot(90            chunkIndex = 0,91            chunkCount = MAX_SNAPSHOT_CHUNKS + 1,92            entries = emptyMap(),93            tombstones = emptyMap(),94        ))95        val error = runCatching { receiveVaultSnapshot(receiver) }.exceptionOrNull()96        assertTrue(error is IllegalStateException)97        assertTrue(error!!.message!!.contains("TOO_MANY_CHUNKS"))98    }99100    @Test101    fun `validates ADOPT_SNAPSHOT frames`() {102        val valid = AdoptionFrame.Snapshot(103            chunkIndex = 0, chunkCount = 1,104            entries = mapOf("a" to "x"), tombstones = emptyMap(),105        )106        assertTrue(isAdoptSnapshot(valid))107        assertTrue(!isAdoptSnapshot(null))108        assertTrue(!isAdoptSnapshot(AdoptionFrame.Complete))109    }110111    @Test112    fun `snapshot_capable serializes in ADOPT_REQUEST`() {113        val request = AdoptionFrame.Request(114            sessionRequestId = "req-1",115            deviceName = "test",116            deviceType = "extension",117            snapshotCapable = true,118        )119        val json = AdoptJson.encodeToString(AdoptionFrame.serializer(), request)120        assertTrue(json.contains("\"snapshot_capable\":true"))121        // Absent when null (encodeDefaults = false)122        val noFlag = AdoptionFrame.Request(123            sessionRequestId = "req-2",124            deviceName = "test",125            deviceType = "extension",126        )127        val jsonNoFlag = AdoptJson.encodeToString(AdoptionFrame.serializer(), noFlag)128        assertTrue(!jsonNoFlag.contains("snapshot_capable"))129    }130131    @Test132    fun `rejects raw frame exceeding wire ceiling`() = runBlocking {133        // H-09: a hostile source could send an arbitrarily large frame to exhaust134        // receiver memory before JSON parsing. receiveVaultSnapshot checks the raw135        // byte length against SNAPSHOT_FRAME_WIRE_CEILING (512 KiB + 256 KiB = 768 KiB)136        // and throws before attempting deserialization.137        val ceiling = MAX_SNAPSHOT_CHUNK_BYTES + 256 * 1024138        val oversized = ByteArray(ceiling + 1)139        val channel = object : PairingTransport {140            override suspend fun send(msg: ByteArray) {}141            override suspend fun receive(): ByteArray = oversized142            override suspend fun close() {}143        }144        val error = runCatching { receiveVaultSnapshot(channel) }.exceptionOrNull()145        assertTrue(error is IllegalStateException)146        assertTrue(error!!.message!!.contains("CHUNK_TOO_LARGE"))147    }148149    @Test150    fun `rejects chunk_count mismatch on subsequent frame`() = runBlocking {151        val (source, receiver) = memoryPair()152        sendFrame(source, AdoptionFrame.Snapshot(153            chunkIndex = 0,154            chunkCount = 2,155            entries = mapOf("a" to "x"),156            tombstones = emptyMap(),157        ))158        sendFrame(source, AdoptionFrame.Snapshot(159            chunkIndex = 1,160            chunkCount = 3,161            entries = mapOf("b" to "y"),162            tombstones = emptyMap(),163        ))164        val error = runCatching { receiveVaultSnapshot(receiver) }.exceptionOrNull()165        assertTrue(error is IllegalStateException)166        assertTrue(error!!.message!!.contains("CHUNK_COUNT_MISMATCH"))167    }168169    @Test170    fun `round-trips duress_slot on final chunk`() = runBlocking {171        val (source, receiver) = memoryPair()172        val entries = mapOf("id-0" to "cipher-0")173        val tombstones = mapOf("dead-0" to 42L)174        val duressJson = """{"version":1,"salt":"aa","nonce":"bb","ciphertext":"cc","tag":"dd"}"""175        sendVaultSnapshot(source, entries, tombstones, duressSlot = duressJson)176        val snapshot = receiveVaultSnapshot(receiver)177        assertEquals(entries, snapshot.entries)178        assertEquals(tombstones, snapshot.tombstones)179        assertEquals(duressJson, snapshot.duressSlot)180    }181182    @Test183    fun `duress_slot absent returns null`() = runBlocking {184        val (source, receiver) = memoryPair()185        sendVaultSnapshot(source, mapOf("id-0" to "cipher-0"), emptyMap())186        val snapshot = receiveVaultSnapshot(receiver)187        assertNull(snapshot.duressSlot)188    }189190    @Test191    fun `duress_slot rides final chunk only in multi-chunk transfer`() = runBlocking {192        val (source, receiver) = memoryPair()193        val big = "x".repeat(200 * 1024)194        val entries = (0 until 5).associate { "id-$it" to big }195        val tombstones = mapOf("dead-0" to 42L)196        val duressJson = """{"version":1,"salt":"ff","nonce":"ee","ciphertext":"dd","tag":"cc"}"""197        sendVaultSnapshot(source, entries, tombstones, duressSlot = duressJson)198        val snapshot = receiveVaultSnapshot(receiver)199        assertEquals(entries, snapshot.entries)200        assertEquals(tombstones, snapshot.tombstones)201        assertEquals(duressJson, snapshot.duressSlot)202    }203204    @Test205    fun `old frame without duress_slot deserializes`() {206        val oldJson = """{"type":"ADOPT_SNAPSHOT","chunk_index":0,"chunk_count":1,"entries":{"a":"x"},"tombstones":{}}"""207        val frame = runCatching {208            AdoptJson.decodeFromString(AdoptionFrame.serializer(), oldJson)209        }.getOrNull()210        assertTrue(isAdoptSnapshot(frame))211        assertTrue((frame as AdoptionFrame.Snapshot).duressSlot == null)212    }213214    // Mirrors browser v4.6.4 T-A33: post-fix regression. With duress on215    // its own frame after the entries chunks, a >768 KiB combined payload216    // round-trips intact; pre-fix this threw ADOPT_SNAPSHOT_CHUNK_TOO_LARGE.217    @Test218    fun `frame ceiling 768KiB duress on separate frame round-trips`() = runBlocking {219        val (source, receiver) = memoryPair()220        val entries = mapOf("id-0" to "x".repeat(450 * 1024))221        val tombstones = mapOf("dead-0" to 1L)222        // Build a sealed-duress JSON literal with a 320 KiB ciphertext field223        // so combined raw payload (450 KiB entry + ~320 KiB duress + envelope)224        // crosses the 768 KiB SNAPSHOT_FRAME_WIRE_CEILING on the legacy wire.225        val duressJson = ("""{"version":1,"salt":"${"a".repeat(16)}",""" +226            """"nonce":"${"b".repeat(12)}",""" +227            """"ciphertext":"${"c".repeat(320 * 1024)}",""" +228            """"tag":"${"d".repeat(16)}"}""")229        sendVaultSnapshot(source, entries, tombstones, duressSlot = duressJson)230        val snapshot = receiveVaultSnapshot(receiver)231        assertEquals(entries, snapshot.entries)232        assertEquals(tombstones, snapshot.tombstones)233        assertEquals(duressJson, snapshot.duressSlot)234    }235236    // Mirrors browser v4.6.4 T-A34: structural proof that the duress wire237    // change is real. With >768 KiB combined, intermediate frames each stay238    // under the ceiling and exactly two frames are sent (entries + duress).239    @Test240    fun `intermediate frame sizes stay under wire ceiling when duress rides its own frame`() = runBlocking {241        val (source, _) = memoryPair()242        val observedRawSizes = mutableListOf<Int>()243        val observedHasDuress = mutableListOf<Boolean>()244        val observedEntriesSize = mutableListOf<Int>()245        val probe = object : PairingTransport {246            override suspend fun send(msg: ByteArray) {247                observedRawSizes.add(msg.size)248                val parsed = runCatching {249                    AdoptJson.decodeFromString(AdoptionFrame.Snapshot.serializer(), String(msg, Charsets.UTF_8))250                }.getOrNull()251                observedHasDuress.add(parsed?.duressSlot != null)252                observedEntriesSize.add(parsed?.entries?.size ?: 0)253                source.send(msg)254            }255            override suspend fun receive(): ByteArray = source.receive()256            override suspend fun close() {}257        }258        val entries = mapOf("id-0" to "x".repeat(450 * 1024))259        val duressJson = "y".repeat(320 * 1024)260        val ceiling = MAX_SNAPSHOT_CHUNK_BYTES + 256 * 1024 // SNAPSHOT_FRAME_WIRE_CEILING261262        sendVaultSnapshot(probe, entries, mapOf("dead-0" to 1L), duressSlot = duressJson)263264        assertEquals(2, observedRawSizes.size)265        // Entries frame carries entries, no duress, under ceiling.266        assertEquals(false, observedHasDuress[0])267        assertEquals(1, observedEntriesSize[0])268        org.junit.Assert.assertTrue(269            "entries frame ${observedRawSizes[0]} should be < ceiling $ceiling",270            observedRawSizes[0] < ceiling271        )272        // Duress frame carries duress, no entries, under ceiling.273        assertEquals(true, observedHasDuress[1])274        assertEquals(0, observedEntriesSize[1])275        org.junit.Assert.assertTrue(276            "duress frame ${observedRawSizes[1]} should be < ceiling $ceiling",277            observedRawSizes[1] < ceiling278        )279        // The point of the split: combined raw exceeds what a single frame280        // was permitted to carry on the old wire.281        org.junit.Assert.assertTrue(282            "combined raw ${observedRawSizes[0] + observedRawSizes[1]} should exceed ceiling $ceiling",283            observedRawSizes[0] + observedRawSizes[1] > ceiling284        )285    }286287    // Mirrors browser v4.6.4 T-A35: backward compat with pre-v2.9.9 senders288    // (duress on entries final chunk). The receiver merges per chunk so both289    // shapes decode.290    @Test291    fun `legacy duress on entries final chunk still decodes`() = runBlocking {292        val (source, receiver) = memoryPair()293        val duressJson = """{"version":1,"salt":"aa","nonce":"bb","ciphertext":"cc","tag":"dd"}"""294        // Manually construct the legacy v2.9.8 wire shape: a single chunk295        // with entries, tombstones AND duress_slot all on it.296        sendFrame(source, AdoptionFrame.Snapshot(297            chunkIndex = 0,298            chunkCount = 1,299            entries = mapOf("id-0" to "ciphertext"),300            tombstones = mapOf("dead-0" to 42L),301            duressSlot = duressJson,302        ))303        val snapshot = receiveVaultSnapshot(receiver)304        assertEquals(mapOf("id-0" to "ciphertext"), snapshot.entries)305        assertEquals(mapOf("dead-0" to 42L), snapshot.tombstones)306        assertEquals(duressJson, snapshot.duressSlot)307    }308309    // Mirrors browser T-A36: cap boundary inclusive. With 199 entries and a310    // duress slot, the sender fits everything within MAX_SNAPSHOT_CHUNKS = 200311    // (199 entries + 1 duress = 200 frames). Duress MUST arrive intact — sync312    // does not carry duress. Sequential pattern matches the rest of the file313    // (channels buffer via UNLIMITED capacity).314    @Test315    fun `duress is reserved a frame so 199 entries plus duress fits in MAX_SNAPSHOT_CHUNKS`() = runBlocking {316        val (source, receiver) = memoryPair()317        val duressJson = """{"version":1,"salt":"aa","nonce":"bb","ciphertext":"cc","tag":"dd"}"""318        val big = "x".repeat(450 * 1024)319        val entries = (0 until 199).associate { "id-$it" to big }320        sendVaultSnapshot(source, entries, mapOf("dead-0" to 1L), duressSlot = duressJson)321        val snapshot = receiveVaultSnapshot(receiver)322        assertEquals(entries, snapshot.entries)323        assertEquals(mapOf("dead-0" to 1L), snapshot.tombstones)324        assertEquals(duressJson, snapshot.duressSlot)325    }326327    // Mirrors browser T-A37: cap boundary exceeded. With 200 entries + duress,328    // the duress frame is reserved (entry cap = MAX_SNAPSHOT_CHUNKS - 1 = 199),329    // so duress still arrives intact. Excess entries (one beyond 199) are330    // deferred to sync. Critically: duress MUST NOT be silently dropped, else331    // the adopted device lacks its duress vault permanently.332    @Test333    fun `200 entries plus duress does not silently drop duress at the chunk cap`() = runBlocking {334        val (source, receiver) = memoryPair()335        val duressJson = """{"version":1,"salt":"aa","nonce":"bb","ciphertext":"cc","tag":"dd"}"""336        val big = "x".repeat(450 * 1024)337        val entries = (0 until 200).associate { "id-$it" to big }338        sendVaultSnapshot(source, entries, mapOf("dead-0" to 1L), duressSlot = duressJson)339        val snapshot = receiveVaultSnapshot(receiver)340        // Duress MUST arrive intact.341        assertEquals(duressJson, snapshot.duressSlot)342        // The inline cap = MAX_SNAPSHOT_CHUNKS - 1 = 199 entries.343        assertEquals(199, snapshot.entries.size)344        assertEquals(mapOf("dead-0" to 1L), snapshot.tombstones)345    }346347    // Cap-pre-check guardrail: a duress payload that itself exceeds the wire348    // ceiling throws ADOPT_SNAPSHOT_DURESS_FRAME_TOO_LARGE before any frame is349    // sent — adoption never silently loses duress.350    @Test351    fun `duress larger than wire ceiling throws loudly before sending`() = runBlocking {352        val (source, _) = memoryPair()353        var frames = 0354        val countingSource = object : PairingTransport {355            override suspend fun send(msg: ByteArray) { frames++; source.send(msg) }356            override suspend fun receive(): ByteArray = source.receive()357            override suspend fun close() {}358        }359        val ceiling = 768 * 1024360        val emptyWireSize = AdoptJson.encodeToString(361            AdoptionFrame.serializer(),362            AdoptionFrame.Snapshot(1, 2, emptyMap(), emptyMap(), ""),363        ).encodeToByteArray().size364        val duressJson = "x".repeat(ceiling - emptyWireSize + 1)365        val error = runCatching {366            sendVaultSnapshot(countingSource, mapOf("id-0" to "small"), emptyMap(), duressSlot = duressJson)367        }.exceptionOrNull()368        assertTrue(error is SnapshotDuressFrameTooLargeException)369        assertEquals(0, frames)370    }371}