This version fixed a few potential security problems found during the ongoing security audit. In addition, it fixed a problem that might cause join network failure.
Security
- Prevent last 2 elements in sigchain to be the same
- Returns error if proposal txn hash list contains duplicate
- Will not cache sigchain txn with invalid txn signature
- Use random neighbor probabilistically chance when stabilize
- Unify fee subtract and nonce increment logic for all txn types
- Check amount and fee range when checking payload
Network
- Connect to random neighbor first when joining the network to improve join reliability