eth2.0-specs/specs/_features/eip7549/validator.md

Deneb -- Honest Validator

Table of contents

• Modifications in EIP-7549
  • Block proposal
    • Constructing the BeaconBlockBody
      • Attester slashings
      • Attestations
  • Attesting
    • Construct attestation
  • Attestation aggregation
    • Construct aggregate

Modifications in EIP-7549

Block proposal

Constructing the BeaconBlockBody

Attester slashings

Changed the max attestations size to MAX_ATTESTER_SLASHINGS_EIP7549.

Attestations

The network attestation aggregates contain only the assigned committee attestations. Attestation aggregates received by the block proposer from the committee aggregators with disjoint committee_bits sets and equal AttestationData SHOULD be consolidated into a single Attestation object. The proposer should run the following function to construct an on chain final aggregate form a list of network aggregates with equal AttestationData:

def compute_on_chain_aggregate(network_aggregates: Sequence[Attestation]) -> Attestation:
    aggregates = sorted(network_aggregates, key=lambda a: get_committee_indices(a.committee_bits)[0])

    data = aggregates[0].data
    aggregation_bits = Bitlist[MAX_VALIDATORS_PER_COMMITTEE * MAX_COMMITTEES_PER_SLOT]()
    for a in aggregates:
        for b in a.aggregation_bits:
            aggregation_bits.append(b)

    signature = bls.Aggregate([a.signature for a in aggregates])

    committee_indices = [get_committee_indices(a.committee_bits)[0] for a in aggregates]
    committee_flags = [(index in committee_indices) for index in range(0, MAX_COMMITTEES_PER_SLOT)]        
    committee_bits = Bitvector[MAX_COMMITTEES_PER_SLOT](committee_flags)

    return Attestation(aggregation_bits, data, committee_bits, signature)

Attesting

Construct attestation

• Set attestation_data.index = 0.
• Let attestation.aggregation_bits be a Bitlist[MAX_VALIDATORS_PER_COMMITTEE * MAX_COMMITTEES_PER_SLOT] of length len(committee), where the bit of the index of the validator in the committee is set to 0b1.
• Let attestation.committee_bits be a Bitvector[MAX_COMMITTEES_PER_SLOT], where the bit at the index associated with the validator's committee is set to 0b1.

Note: Calling get_attesting_indices(state, attestation) should return a list of length equal to 1, containing validator_index.

Attestation aggregation

Construct aggregate

• Set attestation_data.index = 0.
• Let aggregation_bits be a Bitlist[MAX_VALIDATORS_PER_COMMITTEE * MAX_COMMITTEES_PER_SLOT] of length len(committee), where each bit set from each individual attestation is set to 0b1.
• Set attestation.committee_bits = committee_bits, where committee_bits has the same value as in each individual attestation.