EIP-8131: Add Auth Data to EIP-7623 Floor

Add EIP-7702 authorization data to the EIP-7623 floor calculation

Metadata

Status: DraftStandards Track: CoreCreated: 2025-01-21

Authors

Toni Wahrstätter (@nerolation)

Requires

EIP-7623, EIP-7702

Links

GitHub page Discussion on Ethereum Magicians

Abstract

This EIP includes EIP-7702 authorization data in the EIP-7623 floor calculation, preventing circumvention of floor pricing through authorization lists.

Motivation

EIP-7702 authorization tuples are priced for execution (PER_EMPTY_ACCOUNT_COST = 25,000 gas per authorization) but do not contribute to the EIP-7623 floor calculation.

This enables achieving ~9% larger blocks than intended by combining calldata with authorization data at an optimal ratio, circumventing the floor pricing mechanism.

Specification

Parameter	Value	Source
`TOTAL_COST_FLOOR_PER_TOKEN`	`10`	EIP-7623
`FLOOR_COST_PER_AUTH`	`4040`	101 bytes × 4 tokens × 10 gas
`PER_EMPTY_ACCOUNT_COST`	`25000`	EIP-7702

The EIP-7623 floor calculation is modified to include authorization data:

The gas used calculation becomes:

Any transaction with a gas limit below floor_gas or below its intrinsic gas cost is considered invalid.

Rationale

Flat Cost Per Authorization

Each authorization is charged a flat FLOOR_COST_PER_AUTH = 4040 gas toward the floor, derived from:

101 bytes per authorization tuple (as specified in EIP-7702)
4 tokens per byte (treating all bytes as non-zero)
10 gas per token (TOTAL_COST_FLOOR_PER_TOKEN)

This conservative approach avoids byte-level zero/non-zero accounting while ensuring authorization data is properly reflected in the floor calculation.

Floor-Only Modification

Authorization costs are added to the floor calculation only, not to intrinsic gas. This differs from EIP-7981 (access lists) because:

Authorization execution cost (25,000 gas) far exceeds floor contribution (4,040 gas per auth)
Floor-only modification is sufficient to prevent bypass

With this change:

Authorization data contributes to the floor path
High-execution transactions remain unaffected (execution exceeds floor)
Data-heavy transactions cannot use authorizations to bypass floor pricing

Backwards Compatibility

This is a backwards incompatible gas repricing that requires a scheduled network upgrade.

Requires updates to gas estimation in wallets and nodes. Normal usage patterns remain largely unaffected since authorization execution cost typically dominates the floor contribution.

Test Cases

Case 1: Transaction with Authorizations Only

Calldata: 0 bytes
Authorizations: 10

Old floor: 21,000 gas New floor: 21,000 + 10 × 4,040 = 61,400 gas Execution: 10 × 25,000 = 250,000 gas Result: Pay execution (250,000) - unchanged, execution dominates

Case 2: Bypass Attempt (Now Blocked)

Calldata: 100,000 bytes (400,000 tokens)
Authorizations: 100

Old floor: 21,000 + 400,000 × 10 = 4,021,000 gas New floor: 21,000 + 400,000 × 10 + 100 × 4,040 = 4,425,000 gas Execution: 21,000 + 1,600,000 + 2,500,000 = 4,121,000 gas Result: Pay new floor (4,425,000) - bypass blocked

Reference Implementation

Security Considerations

This EIP closes a loophole that allows circumventing EIP-7623 floor pricing. Without this fix, adversaries can achieve ~9% larger blocks by combining calldata with authorization data.

Interaction with EIP-7981

If EIP-7981 is also adopted, both EIPs work together: access list tokens and authorization tokens are both included in the floor calculation. There are no conflicts.

Copyright