805e85e1ff
Time in the beacon chain is expressed relative to the genesis time - this PR creates a `beacon_time` module that collects helpers and utilities for dealing the time units - the new module does not deal with actual wall time (that's remains in `beacon_clock`). Collecting the time related stuff in one place makes it easier to find, avoids some circular imports and allows more easily identifying the code actually needs wall time to operate. * move genesis-time-related functionality into `spec/beacon_time` * avoid using `chronos.Duration` for time differences - it does not support negative values (such as when something happens earlier than it should) * saturate conversions between `FAR_FUTURE_XXX`, so as to avoid overflows * fix delay reporting in validator client so it uses the expected deadline of the slot, not "closest wall slot" * simplify looping over the slots of an epoch * `compute_start_slot_at_epoch` -> `start_slot` * `compute_epoch_at_slot` -> `epoch` A follow-up PR will (likely) introduce saturating arithmetic for the time units - this is merely code moves, renames and fixing of small bugs. |
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| .. | ||
| README.md | ||
| batch_validation.nim | ||
| block_processor.nim | ||
| consensus_manager.nim | ||
| eth2_processor.nim | ||
| gossip_validation.nim | ||
README.md
Gossip Processing
This folder holds a collection of modules to:
- validate raw gossip data before
- rebroadcasting it (potentially aggregated)
- sending it to one of the consensus object pools
Validation
Gossip validation is different from consensus verification in particular for blocks.
- Blocks: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#beacon_block
- Attestations (aggregated): https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#beacon_aggregate_and_proof
- Attestations (unaggregated): https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#attestation-subnets
- Voluntary exits: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#voluntary_exit
- Proposer slashings: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#proposer_slashing
- Attester slashing: https://github.com/ethereum/consensus-specs/blob/v1.1.8/specs/phase0/p2p-interface.md#attester_slashing
There are multiple consumers of validated consensus objects:
- a
ValidationResult.Acceptoutput triggers rebroadcasting in libp2p- We jump into method
validate(PubSub, Message)in libp2p/protocols/pubsub/pubsub.nim - which was called by
rpcHandler(GossipSub, PubSubPeer, RPCMsg)
- We jump into method
- a
blockValidatormessage enqueues the validated object to the processing queue inblock_processorblockQueue: AsyncQueue[BlockEntry](shared with request_manager and sync_manager)- This queue is then regularly processed to be made available to the consensus object pools.
- a
xyzValidatormessage adds the validated object to a pool in eth2_processor- Attestations (unaggregated and aggregated) get collected into batches.
- Once a threshold is exceeded or after a timeout, they get validated together using BatchCrypto.
Security concerns
As the first line of defense in Nimbus, modules must be able to handle bursts of data that may come:
- from malicious nodes trying to DOS us
- from long periods of non-finality, creating lots of forks, attestations