Meshtastic-Android/core/database

:core:database

This module provides the local Room database persistence layer for the application.

Key Components

• MeshtasticDatabase: The main Room database class.
• DAOs (Data Access Objects):
  • NodeInfoDao: Manages storage and retrieval of node information (NodeEntity). Contains critical logic for handling Public Key Conflict (PKC) resolution and preventing identity wiping attacks.
  • PacketDao: Handles storage of mesh packets.
  • ChatMessageDao: Manages chat message history.
• Entities:
  • NodeEntity: Represents a node on the mesh.
  • PacketEntity: Represents a stored packet.

Security Considerations

Public Key Conflict (PKC) Handling

The NodeInfoDao implements specific logic to protect against impersonation and "wipe" attacks:

• Wipe Protection: Receiving an is_licensed=true packet (which normally clears the public key for compliance) will not clear an existing valid public key if one is already known. This prevents attackers from sending fake licensed packets to wipe keys from the DB.
• Conflict Detection: If a new key arrives for an existing node ID that conflicts with a known valid key, the key is set to ERROR_BYTE_STRING to flag the potential impersonation.

Module dependency graph

graph TB
  :core:database[database]:::null

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classDef android-feature fill:#FFD6A5,stroke:#000,stroke-width:2px,color:#000;
classDef android-library fill:#9BF6FF,stroke:#000,stroke-width:2px,color:#000;
classDef android-library-compose fill:#9BF6FF,stroke:#000,stroke-width:2px,color:#000;
classDef android-test fill:#A0C4FF,stroke:#000,stroke-width:2px,color:#000;
classDef jvm-library fill:#BDB2FF,stroke:#000,stroke-width:2px,color:#000;
classDef kmp-library fill:#FFC1CC,stroke:#000,stroke-width:2px,color:#000;
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