Register users only through DApp sign-up

Question

I am making a DApp where users need to be registered in the Solidity smart contract to perform some actions, for example:

function publish (string memory _itemURI) userOnly public {
    // Publish item
}

Where the userOnly modifier is as follows

modifier userOnly {
    require(users[msg.sender] == true, "User only");
    _;
}

Registration is done with this function:

function register(address newUser) public {
    users[newUser] = true;
    emit Register(newUser);
}

The problem is: anyone could call the register function to register there own address, and then be able to call the userOnly functions. Is there a way the register function could only be called only at the end of our DApp sign-up process, like only after the user signs our terms of service with Metamask?

Answer 1

your dapp needs to control a wallet that registers users(hard). registration needs a "dappOnly" modifier or you need to add a comment on the source code that discloses the TOS(easier).