Biconomy: Nexus

Summary

EIP-7579 specifies that "Smart accounts MAY implement a fallback function that forwards the call to a fallback handler. If the smart account has a fallback handler installed, it:

• MUST implement authorization control

• MUST use call to invoke the fallback handler

• MUST utilize ERC-2771 to add the original msg.sender to the calldata sent to the fallback handler

• MUST route to fallback handlers based on the function selector of the calldata"

While implementing this functionality is optional, considering the generic nature of Nexus.sol, it should be implemented to support all the features of EIP-7579 properly.

Impact

Currently, Nexus.sol has no mechanism to forward calls to a fallback handler. This limits its functionality and compliance with EIP-7579, potentially affecting interoperability & extensibility.

Recommendation

Implement a fallback function to forward calls to a fallback handler if applicable. This would ensure complete support for fallback handlers as described in EIP-7579, enhancing the versatility and compliance of Nexus.sol.