Additionally, it makes the Fiat-Shamir hashing logic more robust by making the challenges independent of each other. It also makes it more efficient to implement by moving both challenge computations to a single function needing a single transcript hash.
Co-authored-by: George Kadianakis <desnacked@riseup.net>
Co-authored-by: Dankrad Feist <mail@dankradfeist.de>
When defining a fork transition test, additional spec forks are made
available through `@with_phases(..., other_phases=...)`.
The `with_config_overrides` decorator only applies to the primary phase
so far, which can be unexpected. `with_config_overrides` is adjusted to
override config in subsequent `other_phases` as well.
This commit changes the public API of the KZG library to the following high-level API:
```
- verify_kzg_proof()
- compute_aggregate_kzg_proof()
- verify_aggregate_kzg_proof()
- blob_to_kzg_commitment()
```
compared to the previous much more low-level API:
```
- compute_powers()
- matrix_lincomb()
- lincomb()
- bytes_to_bls_field()
- evaluate_polynomial_in_evaluation_form()
- verify_kzg_proof()
- compute_kzg_proof()
```
This means that all the cryptographic logic (including Fiat-Shamir) is now isolated and hidden in the KZG library and the `validator.md` file ends up being significantly simplified, only calling high-level KZG functions.
Some additional things that this commit does:
- Moves all EIP4844 cryptography into polynomial-commitments.md
- Improves the Fiat-Shamir stack by removing the need for SSZ and by introducing simple domain separators
Co-authored-by: Kevaundray Wedderburn <kevtheappdev@gmail.com>
Co-authored-by: Hsiao-Wei Wang <hsiaowei.eth@gmail.com>
Co-authored-by: Dankrad Feist <mail@dankradfeist.de>
Moving the `is_post_xxx` functions to a separate module allows `genesis`
to also use them (cyclic import from `context` prevented this before).
This allows removing `FORKS_BEFORE_ALTAIR` and `FORKS_BEFORE_BELLATRIX`
constants and adding a more general `is_post_fork` function that needs
less maintenance. This then allows definition of `with_all_phases_from`
to streamline the implementation of the `with_xxx_and_later` decorators.
Future light client protocol extensions may include data from the block
in addition to data from the state, e.g., `ExecutionPayloadHeader`.
To prepare for this, also pass the block to the corresponding functions.
In practice, blocks access is easier than historic state access, meaning
there are no practical limitations due to this change.
Future light client tests will also incorporate execution payload data.
To avoid confusion, rename the current `root` check to `beacon_root`.
Doing this now, as #3066 already requires LC test runners to update.
Currently, `test_single_merkle_proof` only supports `BeaconState` tests.
For future tests, different object classes are desirable. Update format
to allow testing other objects as well.
* Do not overload index with WithdrawalIndex and ValidatorIndex
* a few more bellatrix tests
* use function from other PR
* fix tests
* Update tests/core/pyspec/eth2spec/test/bellatrix/transition/test_transition.py
Co-authored-by: Hsiao-Wei Wang <hsiaowei.eth@gmail.com>
* refactor to reuse bellatrix transitio ntests for all transitions
Co-authored-by: Potuz <potuz@prysmaticlabs.com>
Co-authored-by: Hsiao-Wei Wang <hsiaowei.eth@gmail.com>
Replaces `process_slot_for_light_client_store` which force updates the
`LightClientStore` automatically based on `finalized_header` age with
`try_light_client_store_force_update` which may be manually called based
on use case dependent heuristics if light client sync appears stuck.
Not all use cases share the same risk profile.
Adds `create_light_client_bootstrap` and `create_light_client_update`
functions as a reference implementation for serving light client data.
This also enables a new test harness to verify that light client data
gets applied to a `LightClientStore` as expected.
- Implement all the required glue code to make things executable
- Implement a dummy KZG trusted setup
Co-authored-by: Hsiao-Wei Wang <hsiaowei.eth@gmail.com>
Introduces a new `LightClientBootstrap` structure to allow setting up a
`LightClientStore` with the initial sync committee and block header from
a user-configured trusted block root.
This leads to new cases where the `LightClientStore` is only aware of
the current but not the next sync committee. As a side effect of these
new cases, the store's `finalized_header` may now advance into the next
sync committee period before a corresponding `LightClientUpdate` with
the new sync committee is obtained, improving responsiveness.
Note that so far, `LightClientUpdate.attested_header.slot` needed to be
newer than `LightClientStore.finalized_header.slot`. However, it is now
necessary to also consider certain older updates to try and backfill the
`next_sync_committee`. The `is_better_update` helper is also updated to
improve `best_valid_update` tracking.
`LightClientUpdate` structures currently use different merkle proof root
depending on the presence of `finalized_header`. By always rooting it in
the same state (the `attested_header.state_root`), logic gets simpler.
Caveats:
- In periods of extended non-finality, `update.finalized_header` may now
be outdated by several sync committee periods. The old implementation
rejected such updates as the `next_sync_committee` in them was stale,
but the new implementation can properly handle this case.
- The `next_sync_committee` can no longer be considered finalized based
on `is_finality_update`. Instead, waiting until `finalized_header` is
in the `attested_header`'s sync committee period is now necessary.
- Because `update.finalized_header > store.finalized_header` no longer
holds (for updates with finality), an `is_better_update` helper is
added to improve `best_valid_update` tracking (in the past, finalized
updates with supermajority participation would always directly apply)
This PR builds on prior work from:
- @hwwhww at https://github.com/ethereum/consensus-specs/pull/2829
Various cleanups and minor fixes:
- Consistent terminology:
- `signed_block` -> `attested_block`
- `finalized_block_header` -> `finalized_header`
- `snapshot_period` -> `store_period`
- Use correct block in finality test (`blocks[-1]` instead of new one)
- Add `signed_block_header` func to get header from `SignedBeaconBlock`
- Remove `block_header` from `get_sync_aggregate` helper arguments
- Use `state_transition_with_full_block` as shortcut for multiple calls
- Have `finalized_header` actually be header instead of full block body
- Consistent ordering of `assert` to match structure definition
The producer of `LightClientUpdate` structures usually does not know how
far the `LightClientStore` on the client side has advanced. Updates are
currently rejected when including a redundant `next_sync_committee` not
advancing the `LightClientStore`. Behaviour is changed to allow this.