AntoineSirot / signatures-101

Signatures 101

Introduction

Welcome! This is an automated workshop that will guide you into learning out to use Ethereum signatures in smart contracts, and in meta transactions. It is aimed at developpers that are familiar with Solidity.

How to work on this TD

Introduction

The TD has three components:

• An ERC20 token, ticker TD-SIG-101, that is used to keep track of points
• An evaluator contract, that is able to mint and distribute TD-SIG-101 points

Your objective is to gather as many TD-SIG-101 points as possible. Please note :

• The 'transfer' function of TD-SIG-101 has been disabled to encourage you to finish the TD with only one address
• You can answer the various questions of this workshop with different contracts. However, an evaluated address has only one evaluated contract at a time. To change the evaluated contract associated with your address, call submitExercice() with that specific address.
• In order to receive points, you will have to do execute code in Evaluator.sol such that the function TDERC20.distributeTokens(msg.sender, n); is triggered, and distributes n points.
• This repo contains an interface IExerciceSolution.sol. Your solution contract will have to conform to this interface in order to validate the exercice; that is, your contract needs to implement all the functions described in IExerciceSolution.sol.
• A high level description of what is expected for each exercice is in this readme. A low level description of what is expected can be inferred by reading the code in Evaluator.sol.
• The Evaluator contract sometimes needs to make payments to buy your tokens. Make sure he has enough ETH to do so! If not, you can send ETH directly to the contract.

Getting to work

• Clone the repo on your machine
• Install the required packages npm install truffle, npm install @openzeppelin/contracts@3.4.1 , npm install @truffle/hdwallet-provider, npm i @supercharge/strings
• Rename example-truffle-config.js to truffle-config.js . That is now your truffle config file.
• Configure a seed for deployment of contracts in your truffle config file
• Register for an infura key and set it up in your truffle config file
• Download and launch Ganache
• Test that you are able to connect to the ganache network with truffle console
• Test that you are able to connect to the goerli network with truffle console --network goerli
• To deploy a contract, configure a migration in the migration folder. Look at the way the TD is deploy and try to iterate
• Test your deployment in Ganache truffle migrate
• Deploy on goerli truffle migrate --network goerli --skip-dry-run

Points list

Setting up

• Create a truffle project and configure it on Infura (2pts)
• Create an ERC721 smart contract and a separate minter contract that is allowed to mint ERC721 tokens using ex1_testERC721 (2 pts)

Generating and reading signatures

• Generate a signature and send it to evaluator using ex2_generateASignature (2 pts)
• Add a function getAddressFromSignature in the minter contract. Get points with ex3_extractAddressFromSignature (2 pts)
• Add a function signerIsWhitelisted() similar to bouncerProxy to know if a signer is whitelisted. Get points with ex4_manageWhiteListWithSignature (2 pts)
• Add a function to let anyone claim a token, as long as they provide a signature by an authorized minter. Get points with ex5_mintATokenWithASpecificSignature (3 pts)

Meta transactions

• Deploy bouncerProxy contract and add one of your account (A) as a signer. Get points with ex6_deployBouncerProxyAndWhitelistYourself (3 pts)
• Call Evaluator from bouncerProxy, originatin the tx from an account not whitelisted in bouncerProxy. Get points with ex7_useBouncerProxyToCallEvaluator (4 pts)

All in one

• Finish all the workshop in a single transaction! Write a contract that implements a function called completeWorkshop() when called. Call ex8_allInOne() from this contract. All points are credited to the validating contract.

TD addresses

• Points contracts 0x53e37895Ec887F577EC481549Aeb14B367D1904a
• Evaluator 0x657e2603c61eC6562258d72ce9E2C27E8537F81C