refactor EIP712

[pakim249CAL]

Pull Request

Issue(s) fixed

This pull request:

• fixes Reconsider EIP712 implementation #452, What would be the impact of delegate on the account manager approve system? #444

This POC limits EIP712 changes to only the changes needed to have the domain separator be calculated on runtime so that the proxy contract is the verifying authority rather than the implementation.

It doesn't seem viable to use the full EIP712 openzeppelin implementation right now because it takes up too much bytecode.

[Rubilmax]

Referencing: #453 (comment)

I'd be more incline to approve this change if we at least use ECDSA.recover from OZ

[MerlinEgalite]

I think #444 can be linked to this PR too

[pakim249CAL]

Referencing: #453 (comment)

I'd be more incline to approve this change if we at least use ECDSA.recover from OZ

I haven't tested, but just to give you a quick answer I believe that ECDSA.sol is a big culprit in bytecode waste due to its numerous error messages in the form of strings.

[Rubilmax]

Referencing: #453 (comment)

I'd be more incline to approve this change if we at least use ECDSA.recover from OZ

Approved in the end, because I just compared OZ's implementation to ours. With this change, our way of doing it is very similar to OZ's

[Rubilmax]

There's a catch: each Morpho instance will share the same EIP712 version, because it's stored as a constant. This has no impact as we've discussed before and would require further changes to move it to immutable, so I approve this PR as is.

[Tristan22400]

There's a catch: each Morpho instance will share the same EIP712 version, because it's stored as a constant. This has no impact as we've discussed before and would require further changes to move it to immutable, so I approve this PR as is.

I am not sure to understand your point. What does it change to go from constant to immutable ?

[Rubilmax]

I am not sure to understand your point. What does it change to go from constant to immutable ?

Moving to an immutable would allow it to be set at deployment, customized according to the e-mode or set by governance, for example. So each Morpho instance could in practice have a specific eip712 version