This PR integrates witness-enabled block production, witness-creating
payload execution and stateless cross-validation into the `engine` API.
The purpose of the PR is to enable the following use-cases (for API
details, please see next section):
- Cross validating locally created blocks:
- Call `forkchoiceUpdatedWithWitness` instead of `forkchoiceUpdated` to
trigger witness creation too.
- Call `getPayload` as before to retrieve the new block and also the
above created witness.
- Call `executeStatelessPayload` against another client to
cross-validate the block.
- Cross validating locally processed blocks:
- Call `newPayloadWithWitness` instead of `newPayload` to trigger
witness creation too.
- Call `executeStatelessPayload` against another client to
cross-validate the block.
- Block production for stateless clients (local or MEV builders):
- Call `forkchoiceUpdatedWithWitness` instead of `forkchoiceUpdated` to
trigger witness creation too.
- Call `getPayload` as before to retrieve the new block and also the
above created witness.
- Propagate witnesses across the consensus libp2p network for stateless
Ethereum.
- Stateless validator validation:
- Call `executeStatelessPayload` with the propagated witness to
statelessly validate the block.
*Note, the various `WithWitness` methods could also *just be* an
additional boolean flag on the base methods, but this PR wanted to keep
the methods separate until a final consensus is reached on how to
integrate in production.*
---
The following `engine` API types are introduced:
```go
// StatelessPayloadStatusV1 is the result of a stateless payload execution.
type StatelessPayloadStatusV1 struct {
Status string `json:"status"`
StateRoot common.Hash `json:"stateRoot"`
ReceiptsRoot common.Hash `json:"receiptsRoot"`
ValidationError *string `json:"validationError"`
}
```
- Add `forkchoiceUpdatedWithWitnessV1,2,3` with same params and returns
as `forkchoiceUpdatedV1,2,3`, but triggering a stateless witness
building if block production is requested.
- Extend `getPayloadV2,3` to return `executionPayloadEnvelope` with an
additional `witness` field of type `bytes` iff created via
`forkchoiceUpdatedWithWitnessV2,3`.
- Add `newPayloadWithWitnessV1,2,3,4` with same params and returns as
`newPayloadV1,2,3,4`, but triggering a stateless witness creation during
payload execution to allow cross validating it.
- Extend `payloadStatusV1` with a `witness` field of type `bytes` if
returned by `newPayloadWithWitnessV1,2,3,4`.
- Add `executeStatelessPayloadV1,2,3,4` with same base params as
`newPayloadV1,2,3,4` and one more additional param (`witness`) of type
`bytes`. The method returns `statelessPayloadStatusV1`, which mirrors
`payloadStatusV1` but replaces `latestValidHash` with `stateRoot` and
`receiptRoot`.
* all: add stateless verifications
* all: simplify witness and integrate it into live geth
---------
Co-authored-by: Péter Szilágyi <peterke@gmail.com>
