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An opt-in "internet gateway" toggle lets one connected phone bridge the local geohash channel for mesh-only peers: signed kind-20000 events ride a new nostrCarrier (0x28) packet — directed to the gateway for uplink, broadcast with TTL for downlink — with Schnorr verification at every hop, CourierStore-style quotas, and explicit loop-prevention rules. - BitFoundation: MessageType.nostrCarrier = 0x28 - NostrCarrierPacket: 2-byte-length TLV codec (direction, geohash, signed event JSON), 16 KiB cap, tolerant decoder - GatewayService: closure-injected policy layer — verify gates (sig, kind, #g tag, age, size), uplink quotas (10/min/depositor rate limit, offline queue of 20 total / 5 per depositor, drop-oldest, flush on reconnect), downlink budget (30/min, bounded drop-oldest backlog), bounded loop-prevention ID sets - BLEService: runtime capability bits (advertise .gateway only while the toggle is on, re-announce on change), signed directed uplink sends, carrier ingress with depositor signature verification - Mesh-only senders uplink automatically from sendGeohash when no relay is connected and a reachable peer advertises .gateway; once-per- channel "sent via mesh gateway" notice - UI: gateway toggle beside the Tor toggle, globe header indicator, VoiceOver labels, xcstrings entries Co-Authored-By: Claude Fable 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