RoyaltyGuard

A general mixin for any owned/permissioned contract that allows for fine tuning function guards based off an ALLOW or DENY list. The best example of a use case at this point in time is the enforcement of royalty payouts through selecting which platforms are/arent allowed to move tokens on a users behalf. The implementation used here supports a list being ALLOW/DENY/OFF, with a default setting of OFF.

Contracts

royalty-guard
├─ RoyaltyGuard — "Admin controlled ALLOW/DENY list primitives"
├─ extensions
│  ├─ RoyaltyGuardDeadmanTrigger - "RoyaltyGuard with a renewable deadman switch to turn list off after predefined period of time"
examples
├─ deadman-trigger
│  ├─ DeadmanGuardedERC721 - "GuardedERC721 with the deadman trigger extension"
│  ├─ DeadmanGuardedERC1155 - "GuardedERC1155 with the deadman trigger extension"
├─ GuardedERC721 — "Solmate based ERC721 with Owner restrictions and RoyaltyGuard"
├─ GuardedERC1155 — "Solmate based ERC1155 with Owner restrictionsand RoyaltyGuard"

Safety

This is experimental software and is provided on an "as is" and "as available" basis.

We do not give any warranties and will not be liable for any loss incurred through any use of this codebase.

How it works

RoyaltyGuard is an abstract contract that is meant to be inherrited to integrate with a contract. The main features of the contract are:

1. Configurable list type with options OFF, ALLOW, and DENY.
2. Flexible admin permissioning of Guard (note examples use Owner based permissioning but can leave it to anyone, ROLE based, etc.)

The two different active list types are ALLOW and DENY. In the ALLOW model, functions marked with the checkList modifier will revert with Unauthorized unless the supplied address is on the list. The DENY list takes the opposite approach and will revert if and only if the supplied address is on the list.

Extensions

Deadman Trigger

If the owner/permissioning group hasn't renewed the trigger, anyone can come in and activate the deadman trigger turning the list type to OFF. Even after deadman trigger has been activated, the owner/permissioning group can renew and change the list type to ALLOW or DENY.

The two deadman trigger functions are setDeadmanListTriggerRenewalDuration(uint256 _numYears), another admin guarded function, that renews the deadman switch for _numYears years and activateDeadmanListTrigger(), a public function, used to turn the list type to OFF and is only callable when the current block.timestamp is on or after the returned value from getDeadmanTriggerAvailableDatetime().

Source code at RoyaltyGuardDeadmanTrigger with examples.

How to Integrate

While there are other ways to integrate with RoyaltyGuard, these examples use the least amount of up front code relying on post contract deployment interactions to finish setup.

The end result of this is the RoyaltyGuard integrated into a contract with type OFF, deadman trigger set to 0, all lists empty, and marked functions guarded by the hasAdminPermission function.

The minimal changes needed are inherit the RoyaltyGuard Contract, override ERC165's supportsInterface, implement hasAdminPermission, and attach the checkList to any functions that need guarding.

Example setups can be found in GuardedERC721 and GuardedERC1155.

For more advance setups, a set of internal functions is supplied that can be used for the purpose of setup within a contracts constructor. See RoyaltyGuard.

Usage

Guarded functions are those that are marked with the modifier checkList(address _addr) that checks the list type and changes based on the typing.

The list type can be updated via toggleListType(ListType _newListType) which relies on the implemented function hasAdminPermission(address _addr) returns (bool). The examples leverage use of an Owner to guard access. Valid inputs for ListType are 0 for OFF, 1 for ALLOW, and 2 for DENY.

Adding, removing, and clearing a list also rely on hasAdminPermission(address _addr) returns (bool). The relevant functions here are batchAddAddressToRoyaltyList(ListType _listType, address[] _addrs), batchRemoveAddressToRoyaltyList(ListType _listType, address[] _addrs), and clearList(ListType _listType).

Installation

To install with Foundry:

forge install koloz193/royalty-guard

Acknowledgements

These contracts/readme utilize or were inspired by:

• Solmate
• OpenZeppelin