How to find another contract’s owner to add to another contract?

Question

I am trying to find a way to look up a way to get the owner of an external ERC721 or ERC1155 contract, in order to require that functions with in my contract can only be called if the msg.sender is the same as the owner of the external contract.

My contract is an airdrop contract with three functions to airdrop either Erc20, 721 or 1155 tokens. I want to require that the msg.sender for all three functions is the owner of the ERC20, 721 or 1155 contract.

I can’t seem to find anything within Solidity, or an interface to handle the checking of ownership.

Would a ChainLink oracle work for this situation? If so, is there an oracle that would be recommended? If it can work within Solidity, what would be the best implementation?

Answer 1

The owner() function is usually public, so you can use an interface that consists of an owner() function to get the external contract and it's owner function. You can progress from this example pseudo-code:

interface YourOwnerInterface {
    function owner() external view returns (address);
}

---

address externalOwner = YourOwnerInterface(externalContractAddress).owner();
if(externalOwner != msg.sender){
    // do whatever you would do if the external owner was not the function caller
}