[LSP6] Add REENTRANCYBOOLEAN to AllowedCalls

[skimaharvey]

Withexecute(...):

All reentrant calls will happen in the context of a call so in order to be successful contracts with REENTRANT permission will also need to have some AllowedCalls permissions.

if a contract has:

• REENTRANT permission
• list of multiple allowed calls (one call that will mint and another one that will approve for example)

At the moment I cannot limit the reentrancy to a specific call (for example approve call).

WithexecuteRelayCall(...):

If a signer has the reentrancy permission. All his signed payload could possibly be used in a reentrancy context. However With the below solution we can also limit it to signer + specific allowed calls

Solution

I think we could modify our allowed call standard and append it by 1 byte related to Reantrancy.

The new standard could be:
Standard:Address:Function:ReentrancyBool

Implementation

When verifying AllowedCalls, since we know whether the call is a reentrant call, we can add a bool isReentrantCallparameters to _verifyAllowedCall(...) and check if this particular call is allowed as a reentrant call.

        function _verifyAllowedCall(..., bool isReentrantCall) internal view {
        ...
        bool isAllowedReentrant = true;

        for (uint256 ii = 0; ii < allowedCallsLength; ii += 30) {

            bytes memory chunk = BytesLib.slice(allowedCalls, ii + 1, 29);
            ...
            //if isReentrantCall is true, we check that the last byte value is FF
            if(isReentrantCall && bytes1(bytes29(chunk) << 224) != 0xFF) {
                isAllowedReentrant = false;
            }

            if (isAllowedStandard && isAllowedAddress && isAllowedFunction && isAllowedReentrant) return;
        }

        revert NotAllowedCall(from, to, selector);
    }

[CJ42]

Should we add it to the callTypes when checking the Allowed Calls?