Orba: Safe Account as Resource Lock

What is OneBalance?

OneBalance is a Chain Abstraction Toolkit designed to simplify cross-chain interactions by utilizing Credible Accounts. These accounts enable users to manage funds across multiple blockchains efficiently, allowing for secure deposits and controlled, permissioned withdrawals without relying on global consensus mechanisms.

More details can be found in the official documentation:

• Getting Started with OneBalance and Privy
• Initializing and Depositing onto the OneBalance Smart Account

Safe and Delay Module as Resource Lock

A resource lock ensures that assets remain escrowed until specific conditions or an expiry time are met.
This prevents double-spending and maintains execution integrity in cross-chain transactions.

This repository demonstrates how to use Safe Smart Accounts and a Delay Module as a resource lock.

1. Safe Smart Accounts

• A multi-signature wallet where ownership is shared between the user and a co-signer.
• Transactions require signatures from both parties. User will initiate a transaction, the co-signer will validate it if certains conditions are met.

2. Delay Module

• Enforces a cooldown period before a transaction can be executed.
• Prevents immediate fund access.
• The user has the right to propose a transaction to the delay module, allowing them to retrieve their funds after the cooldown period.

Use Case

The user has 10 USDC on Arbitrum and wants to deposit 8 USDC on Base.

Setup

1. Initialize Wallets

   • Send User Operations that enable the Delay Module and deploy Safes with the user and a co-signer as owners on Arbitrum and Base. The Delay Module is enabled on the Safes.

2. User Deposits Funds on Abritrum

   • The user sends 10 USDC on Arbitrum to the Safe.

User wants to deposit 8 USDC on Base Aave.

1. User prepares a UserOp for the co-signer, allowing him to receive 8 USDC on Arbitrum

   • The user crafts a UserOp to send 8 USDC on Arbitrum, where the funds are locked, to the co-signer and signs it.
   • This signed UserOp serves as collateral for the co-signer’s reimbursement.
   • The co-signer holds onto this signed UserOp until the deposit on Base Aave is completed.

2. Co-signer authorizes withdrawal on Base

   • The co-signer signs a withdrawal request, authorizing the user to receive 8 USDC on Base from the co-signer.

3. User initiates withdrawal and deposit on Base Aave

   • The user crafts another UserOp to call the withdrawal function on Base using the request signed by the co-signer, retrieve 8 USDC, and deposit it into Aave.

4. User requests co-signer’s approval

   • The user requests the co-signer's signature for this UserOp.
   • Co-signer sign it.

5. Execution on Base

   • The UserOp, signed by both the user and the co-signer, is sent to Base to execute:
     • Withdraw 8 USDC from the co-signer.
     • Deposit 8 USDC into Aave.

6. Co-signer reimbursement

   • The signed UserOp, authorizing the co-signer to receive 8 USDC on Arbitrum, is signed by the co-signer and executed on Arbitrum to reimburse him.

Setup and Usage Instructions

Install Dependencies

Run the following command to install the required dependencies:

yarn install

Configure Environment Variables

Copy the .env.example file to .env.local and set your values as follows:

USER_PRIVATE_KEY=<YOUR_PRIVATE_KEY>
COSIGNER_PRIVATE_KEY=<YOUR_PRIVATE_KEY_COOWNER>

ARBITRUM_SEPOLIA_BUNDLER_URL=<YOUR_BUNDLER_URL>
ARBITRUM_SEPOLIA_PAYMASTER_URL=<YOUR_PAYMASTER_URL>

BASE_SEPOLIA_BUNDLER_URL=<YOUR_BUNDLER_URL>
BASE_SEPOLIA_PAYMASTER_URL=<YOUR_PAYMASTER_URL>
BASE_SEPOLIA_RPC=<YOUR_BASE_SEPOLIA_RPC>

COOLDOWN=20
EXPIRATION=60

SAFE_SALT_NONCE=0

Setup Safe Account

Deploy a safe for the user and co-signer keys as owners. The safe is configured with a threshold of 2.

A Delay Module is configured, allowing the user key to execute a transaction after a cooldown. This module locks user funds in the safe for a lock period equal to the cooldown.

Run the following command:

yarn deploy-safe

You will get

#  Base Sepolia
Safe address: 0xb4407F7Fc369e77C8D2889D7085f4d790c2bDF7a , threshold :  2n , owners: [
  '0x529439479855D81E28aDb3a3704471545E14760b',
  '0x758350fad04225c8dF96aD2Ed234121938b35ECD'
]
Delay Module:  0xC6A9Dd6ab4643E6C8DFa7CB7DCAaeb451CC9f956
#  Arbitrum Sepolia
Safe address: 0xb4407F7Fc369e77C8D2889D7085f4d790c2bDF7a , threshold :  2n , owners: [
  '0x529439479855D81E28aDb3a3704471545E14760b',
  '0x758350fad04225c8dF96aD2Ed234121938b35ECD'
]
Delay Module:  0xC6A9Dd6ab4643E6C8DFa7CB7DCAaeb451CC9f956

Setup Fund Provider

Deploy the Fund Provider on Base with the co-signer key. The Fund Provider will be used to provide USDC to the Safe account.

Disclaimer: The Fund Provider contract is for demonstration purposes only and is not intended for production use.

Run the following command:

yarn deploy-fund-provider

Add the Fund Provider address to your .env.local:

FUND_PROVIDER_ADDRESS=<YOUR_FUND_PROVIDER_ADDRESS>

Send USDC to the Safe on Arbitrum and to the Fund Provider on Base

You can get USDC for the user from the Circle faucet here: https://faucet.circle.com/ Send USDC to the safe on arbitrum. These USDC will be locked. Send USDC to the fund provider. These USDC will be used to provide fundson Base.

Check Balance

To check all balances, run:

yarn check-balance

You will get

Fund provider base balance: 10 USDC
#  Arbitrum Sepolia
Lock: 2 USDC
#  Base Sepolia
Lock: 0 USDC
Global balance: 2 USDC

User Signs Claim for USDC Reimbursement on Arbitrum Sepolia

Run the following command to sign the claim for reimbursement:

yarn user-sign-claim-reimbursement

You will get

  Arbitrum Sepolia
Send 0.5 USDC to 0x758350fad04225c8dF96aD2Ed234121938b35ECD on Arbitrum Sepolia
USER_OPERATION: {
  "paymaster": "0x6a6B7f6012ee5bEF1cDf95df25e5045C7727c739",
  "sender": "0xb4407F7Fc369e77C8D2889D7085f4d790c2bDF7a",
  "callData": "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",
  "maxFeePerGas": "120000000",
  "maxPriorityFeePerGas": "600000",
  "nonce": "32085707833393130832632175656960",
  "signature": "0x000000000000000000000000ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
  "paymasterData": "0x0000000000000000000000000000000000000000000000000000000067e39b6b00000000000000000000000000000000000000000000000000000000000012340c534bca663555d229d54221c724ac2c9def5eca2675204065e5373e8b325c344946d02c8bfa3915ed13d69f9dcd5214c24a0706077cdecfcea76f58593c7da51c",
  "paymasterPostOpGasLimit": "20000",
  "paymasterVerificationGasLimit": "600000",
  "callGasLimit": "168564",
  "preVerificationGas": "60869",
  "verificationGasLimit": "100984"
}
User Signature: 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
Saved on ./claim-userop-signed.json

These data are saved in ./claim-userop-signed.json. This will be used by the co-signer to claim their reimbursement.

Deposit USDC on Base Aave

Withdraw 0.5 USDC from the Fund Provider on Base Sepolia and deposit into AAVE.

Run the following command:

yarn deposit-on-base-aave

Co-Signer Claims Funds on Arbitrum

To claim the funds on Arbitrum, the co-signer needs to run the following command:

yarn claim-reimbursement

You will get:

#  Arbitrum Sepolia
Claim Tx Hash: 0x561766407cfe9374ad9ec3130f999d252b3e7c9ebe5f7211560f88eb26255a01

User Starts Unlocking Funds on Arbitrum

This use you User EOA to send the transaction, be sure it got Arbitrum sepolia ETH.

To start unlocking the funds, run:

yarn start-unlock-fund

You will get

Submit send 1.5 USDC to 0x529439479855D81E28aDb3a3704471545E14760b Address to Delay Module
Tx Hash: 0x6ebdb58937e76f8c60dbd90bfa4662885bed49ef2a04f6e07655b3f45d7be752
Start Finalize in 20 seconds.

User Finalizes Unlocking Funds on Arbitrum

This use you User EOA to send the transaction, be sure it got Arbitrum sepolia ETH.

To finalize unlocking the funds, run:

yarn finalize-unlock-fund

You will get

Finalize withdraw
Tx Hash: 0xe309785f28cccddc16e1f40385e83438b0cfff4daefd27efafa257b614fab7b2