PayloadAttributesV1
in spec is consistent with either engine_forkchoiceUpdatedV1
/V2
but not V3
#2280
Labels
bug
Something isn't working
https://github.com/ethereum/execution-apis/blob/v1.0.0-beta.4/src/engine/shanghai.md#request-1
i.e. a payload with the
timestamp
value lower than the Shanghai timestamp (which implies aheadBlockHash
corresponding similarly to a block with a timestamp strictly lower than the payloadtimestamp
, i.e. also lower than the Shanghai timestamp), is compatible with either fcuV1 or fcuV2, but not fcuV3, per https://github.com/ethereum/execution-apis/blob/v1.0.0-beta.4/src/engine/cancun.md#request-1(with Prague not defining its own fcuV4, it doesn't work in Prague for the fcuV3 validation to be as strict as "within the time frame of the Cancun fork", but would have to be read as within the Cancun or Prague fork, but it does not appear the engine API specs as of v1.0.0-beta.4 acknowledge this; separate issue, in any case)
Indeed, the verbiage around allowing
headBlockHash
for fcuV2 corresponding to Paris prevents fcUV1 from being used for Shanghai but not fcuV2 being used for Paris:However,
nimbus-eth1/nimbus/beacon/api_handler/api_forkchoice.nim
Lines 67 to 70 in d795a0e
rejects not only fcUV3/non-null
PayloadAttributesV1
/Paris head block (validly, as that's not a valid combination) but also fcUV2/PayloadAttributesV2
/Paris head block (not validly, because that is an allowed combination).One weird edge case here is, in the fcuV3/null
PayloadAttributes
/Paris or Shanghai head block, is that allowed. The spec isn't very clear here;null
is allowed as one of thepayloadAttributes
parameters, but the fcU3 spec goes out of its way to disallow non-null
PayloadAttributesV1
/V2
exactly the same wayfcUV2
goes out of its way to allow non-null
PayloadAttributesV1
so there's some evident intent to close down backwards compatibility.But at least fcuV2 should allow Paris payloads/head blocks, that much seems evident.
The text was updated successfully, but these errors were encountered: