mirror of
https://github.com/status-im/nimbus-eth2.git
synced 2025-01-09 22:06:21 +00:00
0a4728a241
With checkpoint sync in particular, and state pruning in the future, loading states or state-dependent data may fail. This PR adjusts the code to allow this to be handled gracefully. In particular, the new availability assumption is that states are always available for the finalized checkpoint and newer, but may fail for anything older. The `tail` remains the point where state loading de-facto fails, meaning that between the tail and the finalized checkpoint, we can still get historical data (but code should be prepared to handle this as an error). However, to harden the code against long replays, several operations which are assumed to work only with non-final data (such as gossip verification and validator duties) now limit their search horizon to post-finalized data. * harden several state-dependent operations by logging an error instead of introducing a panic when state loading fails * `withState` -> `withUpdatedState` to differentiate from the other `withState` * `updateStateData` can now fail if no state is found in database - it is also hardened against excessively long replays * `getEpochRef` can now fail when replay fails * reject blocks with invalid target root - they would be ignored previously * fix recursion bug in `isProposed`
Consensus object pools
This folder holds the various consensus object pools needed for a blockchain client.
Object in those pools have passed the "gossip validation" filter according to specs:
- blocks: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#beacon_block
- aggregate attestations: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#beacon_aggregate_and_proof
- unaggregated attestation: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#beacon_attestation_subnet_id
- voluntary exits: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#voluntary_exit
- Attester slashings: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#attester_slashing
- Proposer slashings: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#proposer_slashing
After "gossip validation" the consensus objects can be rebroadcasted as they are optimistically good, however for internal processing further verification is needed. For blocks, this means verifying state transition and all contained cryptographic signatures (instead of just the proposer signature). For other consensus objects, it is possible that gossip validation is a superset of consensus verification (TODO).
The pools presenet in this folder are:
- block_pools:
- block_quarantine: for seemingly valid blocks that are on a fork unknown to us.
- block_clearance: to verify (state_transition + cryptography) candidate blocks.
- blockchain_dag: an in-memory direct-acyclic graph of fully validated and verified blockchain candidates with the tail being the last finalized epoch. A block in the DAG MUST be in the fork choice and a block in the fork choice MUST be in the DAG (except for orphans following finalization). On finalization non-empty epoch blocks are stored in the beacon_chain_db.
- attestation_pool: Handles the attestation received from gossip and collect them for fork choice.
- exit_pool: Handle voluntary exits and forced exits (attester slashings and proposer slashings)