* feat: Implement Request Sync Manager (V2 Sync)
- Add RequestSyncManager to track and attribute sync requests
- Update BitchatPacket and BinaryProtocol to support IS_RSR flag (0x10)
- Update RequestSyncPacket with new TLV fields (sinceTimestamp, fragmentIdFilter)
- Update GossipSyncManager to use unicast sync requests and mark responses as RSR
- Update BLEService to enforce timestamp validation for normal packets and exempt valid RSRs
- Add documentation for the new sync manager mechanism
* fix: Resolve compilation errors in V2 Sync implementation
- Remove duplicate restartGossipManager in BLEService
- Add missing TransportConfig constants for sync
- Add 'sync' log category to BitLogger
- Add missing BitLogger import in GossipSyncManager
* fix: Update tests for V2 Sync changes
- Add requestSyncManager parameter to GossipSyncManager init in tests
- Implement getConnectedPeers stub in RecordingDelegate
- Remove unused variable warning in SubscriptionRateLimitTests
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Co-authored-by: a1denvalu3 <>
Co-authored-by: jack <212554440+jackjackbits@users.noreply.github.com>
Adds rate-limiting to prevent device enumeration attacks via rapid
subscription/disconnect cycles. Without this fix, an attacker could
enumerate ~120 bitchat devices per minute by connecting, subscribing,
capturing the announce packet, then disconnecting and moving to the next.
Key changes:
- Add per-central rate-limit tracking with exponential backoff
- Minimum 2-second interval between announces per central
- Exponential backoff (2x) up to 30 seconds for rapid reconnects
- After 5 rapid attempts, suppress announces entirely (likely attack)
- Clean up stale rate-limit entries after 60-second window
- Clear rate-limit state during panic mode
Configuration:
- bleSubscriptionRateLimitMinSeconds: 2.0
- bleSubscriptionRateLimitBackoffFactor: 2.0
- bleSubscriptionRateLimitMaxBackoffSeconds: 30.0
- bleSubscriptionRateLimitWindowSeconds: 60.0
- bleSubscriptionRateLimitMaxAttempts: 5
Security audit reference: Cure53 BCH-01-004 (Medium severity)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
