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* Harden what a locked or seized device gives away The realistic compromise for many of the people this app is built for is not interception but a phone taken, and often unlocked under coercion. Content encryption is in good shape; these are the gaps around it. Hide notification previews, by default. Notification content is rendered by the system on the lock screen, so it was readable without unlocking: DM alerts carried the sender's nickname and the full message body, and geohash alerts put the geohash in the title. Alerts now state that a DM, mention, or location-channel activity arrived and withhold the rest until the app is opened. userInfo still carries the routing peer ID and deep link, neither of which the system displays, so taps land where they did. A settings toggle restores full previews for anyone who wants them. Default-on is the deliberate part: a phone face-up on a table should not narrate conversations, and someone who wants previews can say so. Cover the window on willResignActive, so the snapshot iOS stores for the app switcher shows a placeholder rather than an open conversation. Opaque rather than blurred, because blurred large text stays partly legible and the snapshot goes to disk. Added synchronously from a UIKit notification with queue: nil, since the capture follows shortly after and an OperationQueue hop or a SwiftUI state change can lose that race. Panic wipe already deleted snapshots already on disk; this stops new ones from being worth deleting. Bound media by age as well as size. The 100 MB quota only ever considered incoming files, so outgoing media had no lifetime at all and a received photo could outlive its conversation indefinitely. A launch-time sweep now deletes managed media older than seven days, incoming and outgoing, with the same exemptions quota eviction honors: in-flight live captures and files reserved by a delivery or deletion in progress. Make /clear tell the truth on the mesh timeline. It recorded an echo watermark and left the gossip archive on disk for up to 6 hours, so someone who cleared before a police stop had deleted nothing. Clearing now erases the archive too. The watermark still matters: it suppresses pre-clear messages this device hears again from peers. The cost is that the device stops serving recent public backlog until it hears fresh traffic, which is a fair reading of what clearing a timeline means. Documented in PRIVACY_POLICY.md and the privacy assessment, including a new section on what is deliberately NOT addressed: there is still no duress mechanism of any kind (no decoy passphrase, no wipe-on-failed-auth, no app lock), macOS gets no file-protection classes, and media is not sealed at the app layer. The duress question is a product decision as much as an engineering one, since in some jurisdictions destroying data on demand is itself an offence and hiding may protect someone better than destroying, so it is called out rather than guessed at. Three findings from the audit that prompted this work turned out to be already fixed on main and are not included: keychain accessibility is AfterFirstUnlockThisDeviceOnly with a retrying migration, the panic media wipe uses a two-location durable marker transaction, and panic already discards staged share-extension content. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> * Inject the previews preference instead of reading shared defaults CI caught a real problem this introduced. `NotificationServiceTests` already asserted the full-preview title and body, and both it and the new redaction tests read `NotificationPrivacySettings` from `UserDefaults.standard` in the same process. Whichever ran second depended on the other's cleanup, so it passed locally and failed in CI: XCTAssertEqual failed: ("🔒 new dm") is not equal to ("🔒 DM from Alice") Fixed at the source rather than by ordering or serialization. `NotificationService` now takes a `hidePreviewsProvider`, defaulting to the real preference, so each test states which behavior it asserts. The pre-existing test asks for previews shown and gains a redacted counterpart; the redaction tests no longer touch the shared store. `NotificationPrivacySettings` also gained store-injecting accessors so the default-value and round-trip assertions can use an isolated suite rather than mutating preferences other tests read. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> --------- Co-authored-by: jack <jackjackbits@users.noreply.github.com> Co-authored-by: Claude Opus 5 <noreply@anthropic.com>
Test Harness Guide
This test suite uses an in-memory networking harness to make end-to-end and integration tests deterministic, fast, and race-free without touching production code.
In-Memory Bus
- File:
bitchatTests/Mocks/MockBLEService.swift - Registry/Adjacency: Global
registrymapspeerIDto aMockBLEServiceinstance;adjacencyrecords simulated links between peers. - Setup: Call
MockBLEService.resetTestBus()insetUp()to clear state between tests. - Topology: Use
simulateConnectedPeer(_:)andsimulateDisconnectedPeer(_:)to add/remove links.connectFullMesh()helpers in tests build larger topologies. - Handlers: Tests can observe data via
messageDeliveryHandler(decodedBitchatMessage) andpacketDeliveryHandler(rawBitchatPacket). - De‑duplication: A thread-safe
seenMessageIDsprevents duplicate deliveries during flooding/relays.
Broadcast Flooding
- Flag:
MockBLEService.autoFloodEnabled - Intent: When
true, public broadcasts propagate across the entire connected component (ignores TTL for reach) while still de‑duping to prevent loops. - Usage: Enabled in Integration tests (
setUp) to simulate large-network broadcast; disabled in E2E tests to keep routing explicit and verify TTL behavior (seePublicChatE2ETests.testZeroTTLNotRelayed).
Rehandshake Flow (Noise)
- Why: The legacy NACK recovery path was removed; recovery now relies on Noise session rehandshake after decrypt failure or desync.
- Manager:
NoiseSessionManagermanages per-peer sessions. - Pattern: On decrypt failure, proactively clear the local session and re-initiate a handshake. The peer accepts and replaces their session.
- Test:
IntegrationTests.testRehandshakeAfterDecryptionFailure- Corrupts ciphertext to induce a decrypt error.
- Calls
removeSession(for:)on the initiator’s manager beforeinitiateHandshake(with:)to avoidalreadyEstablished. - Verifies encrypt/decrypt succeeds post-rehandshake.
Tips
- Determinism: Add small async delays only where handler installation/topology changes could race the first send.
- Scoping: Keep
autoFloodEnabledtoggled only within Integration tests; always reset intearDown()to avoid cross-test contamination. - Direct vs Relay: Private messages target a specific peer when adjacent; otherwise they are surfaced to neighbors for relay and, if known, also delivered to the target.
Quick Start
- Create nodes and connect them:
let svc = MockBLEService(); svc.myPeerID = "PEER1"svc.simulateConnectedPeer("PEER2")
- Observe messages:
svc.messageDeliveryHandler = { msg in /* asserts */ }
- Enable broadcast flooding for Integration suites only:
MockBLEService.autoFloodEnabled = true