Build a BrightID Verified User Registry contract

[spengrah]

Build a BrightID Verified User Registry contract

Prize Bounty

500 DAI

Challenge Description

Clr.fund is building a permissionless and credibly neutral quadratic funding protocol and application that is built with zk-snark magic, courtesy of the Minimal Anticollusion Infrastructure MACI.

A critical property of quadratic funding is the assurance that each contributor is in fact a unique individual. We would like to use BrightID to ensure this.

To earn this bounty, you should implement a VerifiedUserRegistry contract that ensures only BrightID verified users can sign as contributors to each round of clr.fund.

Submission Requirements

A valid submission should include a demonstration and source code of working contract that Verified User Registry contract that allows only BrightID verified users to sign up as contributors to each clr.fund round.

To add BrightID support we need to create a contract which will conform to the VerifiedUserRegistry interface:

pragma solidity ^0.5.8; 
 pragma experimental ABIEncoderV2; 
  
 /** 
  * @dev Interface of the registry of verified users. 
  */ 
 interface IVerifiedUserRegistry { 
  
   function isVerifiedUser(address _user) external view returns (bool); 
  
 }

Judging Criteria

This bounty will be awarded to the participant who submits the best version of this contract as judged by the clr.fund contributors.

Winner Announcement Date

Shortly after the event.

[xuhcc]

MACI uses SignUpGatekeeper contract to determine who can sign up for voting. We need to create our own signup gatekeeper integrated with BrightID contract.

[adamstallard]

We will create a smart contract for the clrfund context that implements this interface https://github.com/BrightID/BrightID-SmartContract/blob/master/v4/IBrightID.sol

When someone uses the /verifications endpoint from a BrightID node, they will get a signed verification that they can use to register with that contract.

We can add a register function in our contract that matches the signature of what is called in the MACI signUp function . Our register function would check that they have a verification. We can also look through their history to make sure they haven't signed up already using a different address.

[xuhcc]

We need to create our own signup gatekeeper integrated with BrightID contract.

Currently the FundingRound contract acts as a MACI gatekeeper (https://github.com/clrfund/monorepo/blob/v0.1.0/contracts/contracts/FundingRound.sol#L137-L155). User verification is handled by a separate contract, VerifiedUserRegistry. The registry contract must implement isVerifiedUser(address _user) method and in the near future clr.fund admin will be able to choose the registry at deployment (I've just published a new pull request allowing this: #131).

To add BrightID support we need to create a contract which will conform to the VerifiedUserRegistry interface:

monorepo/contracts/contracts/verifiedUserRegistry/IVerifiedUserRegistry.sol

Lines 1 to 11 in 40a3bfc

	pragma solidity ^0.5.8;
	pragma experimental ABIEncoderV2;
	/**
	* @dev Interface of the registry of verified users.
	*/
	interface IVerifiedUserRegistry {
	function isVerifiedUser(address _user) external view returns (bool);
	}

[adamstallard]

We can make a contract that implements both the IVerifiedUserRegistry interface @xuhcc showed above and the IBrightID interface from here: https://github.com/BrightID/BrightID-SmartContract/blob/master/v4/IBrightID.sol#L3-L7

An example implementation that accepts signed verifications from a BrightID node is here: https://github.com/BrightID/BrightID-SmartContract/blob/master/v4/BrightID.sol

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

---

This issue now has a funding of 500.0 DAI (500.0 USD @ $1.0/DAI) attached to it.

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[adamstallard]

Here's an example deep-link to allow someone to link their BrightID to the clr.fund context
https://app.brightid.org/link-verification/http:%2f%2fnode.brightid.org/clr.fund/0xdc0046b52e2e38aee2271b6171ebb65ccd337518/

This is the version of it that you should turn into a QR code:
brightid://link-verification/http:%2f%2fnode.brightid.org/clr.fund/0xdc0046b52e2e38aee2271b6171ebb65ccd337518/

This is how you see all verified users in the context: https://app.brightid.org/node/v5/verifications/clr.fund

This is how you check one user by contextid: https://app.brightid.org/node/v5/verifications/clr.fund/0xdc0046b52e2e38aee2271b6171ebb65ccd337518

This is how you allow a user to get signed verification for the ethereum contract mentioned above
contextid:https://app.brightid.org/node/v5/verifications/clr.fund/0xdc0046b52e2e38aee2271b6171ebb65ccd337518?signed=eth

Producing these is outside of the scope of this issue / bounty, but these calls may be useful for testing.

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

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Work for 500.0 DAI (500.00 USD @ $1.0/DAI) has been submitted by:

---

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• $894,940.67 more funded OSS Work available on the Gitcoin Issue Explorer

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

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Work for 500.0 DAI (500.00 USD @ $1.0/DAI) has been submitted by:

1. @rezahsnz
2. @siftal

@auryn-macmillan please take a look at the submitted work:

• PR by @siftal
• PR by @rezahsnz

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[xuhcc]

Implemented in #157