Clipper hosts a bug bounty on Immunefi at the address https://www.immunefi.com/bounty/clipper.
If you have found a vulnerability in our project, it must be submitted through Immunefi's platform. Immunefi will handle bug bounty communications. Please see the bounty page at Immunefi for more details on accepted vulnerabilities, payout amounts, and rules of participation. Users who violate the rules of participation will not receive bug bounty payouts and may be temporarily suspended or banned from the bug bounty program.
- ClipperRouter: A stateless implementation of the "Deposit, then Swap" interaction modality (see below).
- ClipperPool: Core vault contract that holds pool assets.
- ClipperExchangeInterface: Automated market making logic.
- ClipperDeposit: Time-locked deposit contract.
- BlacklistAndTimeFilter: Implements logic to deny swaps or deposits. By default, prevents deposits from or swaps to OFAC-listed ETH wallets.
All the Solidity code is written for version 0.8, hence the limited use of the standard OpenZeppelin SafeMath libraries.
We use the "Deposit, then Register" modality of several current-generation DEXs. Under this design, the Pool, ExchangeInterface, and Deposit contracts never activate a transfer from a user. Rather:
- Our Pool contract keeps a snapshot of asset balances at the last time they were synced.
- Users start by transferring assets to the Pool.
- The contracts discover what the user did based on differences between current values and snapshotted values.
- After an interaction, the contracts take another snapshot, through a call to
_sync.
NB: Users risk the loss of their input funds if the asset transfer and sync happen in different transactions. The provided Router contract implements swapping logic in a single transaction and is recommended for transactions with the exchange.
To deposit, transfer tokens or ETH to the Pool contract, and then call deposit on the Deposit contract. The CollectionContract provides a demonstration of the deposit interaction logic. NB: At initial deployment, deposit functionality is not open to the public. If you send tokens to the Clipper pool with the intent to deposit them, your funds will be lost without any recourse.
To perform a swap, transfer tokens or ETH to the Pool contract, and then call the appropriate API function on the ExchangeInterface contract (or Pool contract, which just forwards to the ExchangeInterface contract). The Router contract provides a demonstration of the swap logic.
To withdraw, start by unlocking the deposit with unlockVestedDeposit on the Deposit contract (this is not necessary when making an on-demand deposit). Then either call withdraw or withdrawInto on the ExchangeInterface contract.
withdrawpulls out your pro rata share of every token in the pool.withdrawIntoproposes a swap from the pool token to one of the assets in the pool. The automated market maker will accept that swap if it does not decrease its invariant.
In general, the code in this repository is released under the Business Source License 1.1. This license has two periods: a restricted period, in which the code is not under an open-source license, followed by an open-source period, under which the code will be licensed under the GPLv2. The change date between the two licenses is July 4, 2023. Please see LICENSE.txt for additional information.
Certain auxiliary Solidity source files are taken verbatim or with trivial modification from files released under different licensing. We have preserved that original licensing where appropriate.
npm install --save-dev hardhat
npx hardhat compile; npx hardhat size-contracts
A limited test suite of key exchange functionality is included.
npx hardhat test