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jackandClaude Opus 4.8
0558c2bc82
BLE announce trust verified the packet signature against the Ed25519 signing key carried inside the same announce, and the trust policy only rejected on noise-key mismatch. Since peerIDs derive from the broadcast (public) noise key, an on-mesh attacker could replay a victim's peerID+noiseKey with their own signing key, nickname, and a valid self-signature; the registry/persisted identity was then overwritten unconditionally, enabling mesh nickname spoofing and forged attribution of signed public/broadcast messages. Fix: TOFU-pin the Ed25519 signing key per peer (noise-key-derived peerID) on the announce path. - BLEAnnounceTrustPolicy rejects announces whose signing key differs from the one already recorded for the peer (.signingKeyMismatch). - BLEPeerRegistry.upsertVerifiedAnnounce refuses to replace a pinned signing key (returns nil) and never drops a pinned key. - BLEAnnounceHandler falls back to the persisted cryptographic identity (persistedSigningPublicKey) when the registry has no signing key, so the pin survives registry eviction and app restart. - SecureIdentityStateManager.upsertCryptographicIdentity refuses to replace a persisted signing key with a different one, and the cryptographic identities (incl. the pin) now live in the encrypted, persisted IdentityCache with synchronous, teardown-safe saves. Rebased onto main and integrated with #1432 (Noise session identity binding + signed leaves): both are complementary. #1432's signed-leave verification reads the same registry/persisted signing key that this change protects from announce-path poisoning. main's evolution is kept: BLEPeerRegistry.upsertVerifiedAnnounce still takes capabilities/ bridgeGeohash (nil return propagates as a refusal), the handler's linkBoundToOtherPeer env is preserved, CryptographicIdentity keeps main's field set, and EphemeralIdentity uses main's initializer. Co-Authored-By: Claude Opus 4.8 <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