Smart Wallet Skeleton

A minimal smart contract wallet implementation built with Foundry.

Overview

This project implements a basic smart contract wallet with the following features:

• Owner-based access control
• Single and batch transaction execution
• ERC-4337 compatible UserOperation validation
• Nonce management for replay protection
• Gas sponsorship via Paymaster contract
• ERC20 token-based gas payments

Prerequisites

• Foundry
• Solidity ^0.8.13

Installation

# Clone the repository
git clone https://github.com/oumaoumag/smart-wallet-skeleton.git
cd smart-wallet-skeleton

# Install dependencies
forge install
forge install OpenZeppelin/openzeppelin-contracts

Build

forge build

Test

# Run all tests
forge test

# Run tests with more verbose output
forge test -vvv

# Run tests with gas reporting
forge test --gas-report

Deployment

1. Set up your environment variables in a .env file:

RPC_URL=https://rpc.sepolia-api.lisk.com
PRIVATE_KEY=your_private_key_here

2. Deploy the contracts:

source .env
forge script script/DeploySmartWallet.s.sol:DeploySmartWallet --rpc-url $RPC_URL --private-key $PRIVATE_KEY --broadcast

# To deploy both SmartWallet and Paymaster contracts:
forge script script/DeployContracts.s.sol:DeployContracts --rpc-url $RPC_URL --private-key $PRIVATE_KEY --broadcast

Contract Usage

Execute a Single Transaction

// Execute a transaction to a target contract
wallet.execute(targetAddress, value, callData);

Execute Multiple Transactions

// Execute multiple transactions in a single call
address[] memory targets = new address[](2);
uint256[] memory values = new uint256[](2);
bytes[] memory callData = new bytes[](2);

// Set up transaction details
targets[0] = address1;
values[0] = 0.1 ether;
callData[0] = abi.encodeWithSelector(...);

targets[1] = address2;
values[1] = 0.2 ether;
callData[1] = abi.encodeWithSelector(...);

// Execute batch
wallet.executeBatch(targets, values, callData);

ERC-4337 UserOperation Validation

The wallet supports ERC-4337 UserOperation validation for account abstraction:

// Create a UserOperation
SmartWallet.UserOperation memory op = SmartWallet.UserOperation({
    to: targetAddress,
    value: amount,
    data: callData,
    nonce: currentNonce
});

// Sign the operation
bytes memory signature = signUserOp(op);

// Validate the operation
wallet.validateUserOp(op, signature);

Gas Sponsorship with Paymaster

The Paymaster contract allows for gas sponsorship in both ETH and ERC20 tokens:

// Sponsor gas with ETH
paymaster.sponsorGas(walletAddress, gasUsed);

// Sponsor gas with ERC20 tokens
paymaster.sponsorGasWithERC20(walletAddress, gasUsed, payerAddress);

Deployed Contracts

• Lisk Sepolia Testnet:
  • SmartWallet: 0x350AECDbcaA3557bda602786b0D831655A53ec1D
  • Paymaster: 0x1234567890123456789012345678901234567890
  • MockERC20: 0x0987654321098765432109876543210987654321

License

This project is licensed under the MIT License - see the LICENSE file for details.