--- eip: 2474 title: Coinbase calls author: Ricardo Guilherme Schmidt (@3esmit) discussions-to: https://ethresear.ch/t/gas-abstraction-non-signed-block-validator-only-procedures/4388/2 status: Stagnant type: Standards Track category: Core created: 2020-01-19 --- ## Simple Summary Allow contracts to be called directly by `block.coinbase` (block validator), without a transaction. ## Abstract _In proof-of-work blockchains, validators are known as miners._ The validator might want to execute functions directly, without having to sign a transaction. Some examples might be presenting a proof in a contract for an change which also benefits the validator. A notable example would be when a validator want to act as an [EIP-1077](./eip-1077.md) Gas Relayer, incentivized to pick up fees from meta transactions. Without this change, they can do so by signing from any address a `gasPrice = 0` transaction with the gas relayed call. However this brings an overhead of a signed transaction by validator that does nothing, as `msg.sender` is never used, and there is no gas cost to EVM charge. This proposal makes possible to remove this unused ecrecover. ## Motivation In order to reduce the overhead of calls that don't use `msg.sender` and are being called by validator with `tx.gasPrice = 0`. ## Specification The calls to be executed by `block.coinbase` would be included first at block, and would consume normally the gas of block, however they won't pay/cost gas, instead the call logic would pay the validator in other form. Would be valid to execute any calls without a transaction by the block coinbase, except when the validator call tries to read `msg.sender`, which would throw an invalid jump. Calls included by the validator would have `tx.origin = block.coinbase` and `gas.price = 0` for the rest of call stack, the rest follows as normal calls. ## Rationale TBD ## Backwards Compatibility `tx.origin = block.coinbase` could cause some issues on bad designed contracts, such as using `tx.origin` to validate a signature, an analysis on how contracts use tx.origin might be useful to decide if this is a good choice. ## Test Cases TBD ## Implementation TBD ## Security Considerations TBD ## Copyright Copyright and related rights waived via [CC0](../LICENSE.md).