forked from DecentralizedClimateFoundation/DCIPs
43 lines
3.4 KiB
Markdown
43 lines
3.4 KiB
Markdown
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---
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eip: 1285
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title: Increase Gcallstipend gas in the CALL opcode
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author: Ben Kaufman <ben@daostack.io>, Adam Levi <adam@daostack.io>
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discussions-to: https://ethereum-magicians.org/t/eip-1285-increase-gcallstipend-gas-in-the-call-opcode/941
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status: Stagnant
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type: Standards Track
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category: Core
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created: 2018-08-01
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---
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## Simple Summary
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Increase the ``Gcallstipend`` fee parameter in the ``CALL`` opcode from ``2,300`` to ``3,500`` gas units.
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## Abstract
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Currently, the ``CALL`` opcode forwards a stipend of ``2,300`` gas units for a non zero value ``CALL`` operations where a contract is called. This stipend is given to the contract to allow execution of its ``fallback`` function. The stipend given is intentionally small in order to prevent the called contract from spending the call gas or performing an attack (like re-entrancy).
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While the stipend is small it should still give the sufficient gas required for some cheap opcodes like ``LOG``, but it's not enough for some more complex and modern logics to be implemented.
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This EIP proposes to increase the given stipend from ``2,300`` to ``3,500`` to increase the usability of the ``fallback`` function.
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## Motivation
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The main motivation behind this EIP is to allow simple fallback functions to be implemented for contracts following the ``"Proxy"`` pattern. Simply explained, a ``"Proxy Contract"`` is a contract which use ``DELEGATECALL`` in its ``fallback`` function to behave according to the logic of another contract and serve as an independent instance for the logic of the contract it points to.
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This pattern is very useful for saving gas per deployment (as Proxy contracts are very lean) and it opens the ability to experiment with upgradability of contracts.
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On average, the ``DELEGATECALL`` functionality of a proxy contract costs about ``1,000`` gas units.
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When a contract transfers ETH to a proxy contract, the proxy logic will consume about ``1,000`` gas units before the ``fallback`` function of the logic contract will be executed. This leaves merely about 1,300 gas units for the execution of the logic. This is a severe limitation as it is not enough for an average ``LOG`` operation (it might be enough for a ``LOG`` with one parameter).
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By slightly increasing the gas units given in the stipend we allow proxy contracts have proper ``fallback`` logic without increasing the attack surface of the calling contract.
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## Specification
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Increase the ``Gcallstipend`` fee parameter in the ``CALL`` opcode from ``2,300`` to ``3,500`` gas unit.
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The actual change to the Ethereum clients would be to change the ``CallStipend`` they store as a constant.
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For an implementation example you can find a Geth client implementation linked [here](https://github.com/ben-kaufman/go-ethereum/tree/eip-1285). The actual change to the code can be found [here](https://github.com/ben-kaufman/go-ethereum/blob/eip-1285/params/protocol_params.go#L41).
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## Rationale
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The rational for increasing the ``Gcallstipend`` gas parameter by ``1,200`` gas units comes from the cost of performing ``DELEGATECALL`` and ``SLOAD`` with a small margin for some small additional operations. All while still keeping the stipend relatively small and insufficient for accessing the storage or changing the state.
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## Backwards Compatibility
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This EIP requires a backwards incompatible change for the ``Gcallstipend`` gas parameter in the ``CALL`` opcode.
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## Copyright
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Copyright and related rights waived via [CC0](../LICENSE.md).
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