Crypto index platform, that simplifies your investments through automated, themed index products.
Platform: Code4rena
Start Date: 19/04/2022
End Date: 21/04/2022
Period: 3 days
Status: Completed
Pot Size: $30,000 USDC
Participants: 43
Reporter: liveactionllama
Judges: moose-code,
JasoonS
Id: 90
League: ETH
Auditor per page
| Glossary | |
|---|---|
| BP | Base points = 10000 - not to be confused with basis points |
| vTokens | Vault tokens that are created for each asset in a vault |
| NAV | Net Asset Value - the summation of the value of each token within an index |
| Managed Index | An index where the creator can control weights and assets |
| Tracked Index | An index where assets are immutable after creation but weights change based on stored/updated capitalisation data |
| TopN Index | An index where both weights and assets are programmtically decided based on a categories contract |
Representatives from Phuture will be available in the Code Arena Discord to answer any questions during the contest period. The focus for the contest is to try and find any logic errors or ways to drain funds from the protocol in a way that is advantageous for an attacker at the expense of users with funds invested in the protocol. Wardens should assume that governance variables are set sensibly (unless they can find a way to change the value of a governance variable, and not counting social engineering approaches for this).
Phuture is an asset management protocol initially focused on crypto index products.
Our protocol provides the functionality to mint, redeem and create index products. We utilise a vault design to store the underlying assets of the index and these vaults can have additional "controllers" added to them to support extra functionality or strategies. At launch we have integrated a yearn vault controller that allows us to move some of the index funds over to yearn to earn additional interest. vTokens are created for each token held in a vault and allow us to account for assets which are held in our contracts plus the contracts of other protocols (such as yearn).
Rebalancing of these indices is executed against the liquidity held on Uniswap v2 and Sushiswap. Our contracts create a set of orders for each index that will bring that index back to it's correct balance. These orders are then executed by our keeper. In most cases, orders are too large to execute in one go due to price impact, so our smart contracts scale the orders down to adhere to a specific price impact.
Fees are taken during the minting and redemption process. In addition, we charge a fee annually for the management of the index products.
The protocol's base curreency is USDC and as such the net asset value of each index is calculated in USDC.
Each of the contracts, interfaces and libraries in the /contracts folder is documented in detail with NatSpec. <br /> We recommend that you familiarize yourself with each of the files before or during the contest.
| Name | Type | Description | Lines of code |
|---|---|---|---|
| AUMCalculationLibrary | Library | AUM fee calculation library – contains constant used for AUM fee calculation to prevent underflow and power function for AUM fee calculation | 59 |
| BP | Library | Base point library – Contains constant used to prevent underflow of math operations | 4 |
| FixedPoint112 | Library | A library for handling binary fixed point numbers, see https://en.wikipedia.org/wiki/Q_(number_format) | 5 |
| FullMath | Library | Contains 512-bit math functions. Facilitates multiplication and division that can have overflow of an intermediate value without any loss of precision. Handles "phantom overflow" i.e., allows multiplication and division where an intermediate value overflows 256 bits | 67 |
| IndexLibrary | Library | Provides various utilities for indexes: constants for initial index quantity to mint and total assets weight within an index, function that returns amount of asset equivalent to the given parameters | 16 |
| NAV | Library | Library for transfer, mint, burn and distribute vToken shares – used in conjunction with vToken | 79 |
| BaseIndex | Contract | Contains common logic for all indices: mint & burn (with delegatecalls to indexLogic contract inside), active & inactive anatomies getters | 67 |
| ChainlinkPriceOracle | Contract | Contains logic for getting asset's price from Chainlink data feed. Oracle works through base asset which is set in initialize function. There is method addAsset which sets Chainlink metadata (Aggregator address & answer decimals) and asset decimals to the mapping of asset Infos. And two methods for getting value of asset per base in UQ format (view function lastAssetPerBaseInUQ and state-changing function refreshedAssetPerBaseInUQ) | 66 |
| IndexLayout | Contract | Contains storage layout of index: its IndexFactory – factory, vTokenFactory – vTokenFactory and global IndexRegistry - registry, Timestamp of last AUM fee charge - lastTransferTime, and 2 sets of assets addreses – assets & inactiveAssets, as well as their weights in form of mapping – weightOf | 12 |
| IndexLogic | Contract | Contains common logic for index minting and burning | 111 |
| ManagedIndex | Contract | Contains initialization and reweighting logic for managed type of indexes. Initialization is called only by IndexFactory and its logic is pretty straightforward – loop over the list of assets adding every address to the assets (EnumerableSet.AddressSet from IndexLayout) set and setting weight of assets to weightOf (mapping(address => uint8) from IndexLayout). Reweight method validates sender and delegates call to IManagedIndexReweightingLogic.reweight selector | 44 |
| ManagedIndexReweightingLogic | Contract | Contains reweighting logic for ManagedIndex contract. This index reweighs manually by it's addmin | 81 |
| PhutureIndex | Contract | Wraps the IndexLayout and ERC20 contracts, overriding the name & symbol (by calling NameRegistry symbolOfIndex and nameOfIndex methods), and adding AUM fee logic - the _chargeAUMFee method, which will be executed on every transfer that calculates (using the rpow method from the AUMCalculationLibrary) and mints the AUM fee for the index factory | 47 |
| PhuturePriceOracle | Contract | Aggregates all price oracles and works with them through IPriceOracle interface. Contains oracles management logic: priceOracleOf mapping and setOracleOf, removeOracleOf and containsOracleOf external methods. And the logic for getting last and refreshed values of asset per base in UQ format (calling set oracle of the asset passed as a param, or returning FixedPoint112.Q112 constant in case of _asset param equals base) | 58 |
| TopNMarketCapIndex | Contract | Contains initialization and reweighting logic for top N market capitalization type of index. Initialization is called only by IndexFactory, it iterates through the _assets param, calculating weight for each asset (based on the relation of its market cap to the total capitalization value) and setting it to weightOf (mapping(address => uint8) from IndexLayout) as well as adding an asset itslelf to the assets (EnumerableSet.AddressSet from IndexLayout). Reweight method validates sender and delegates call to ITopNMarketCapIndexReweightingLogic.reweight selector | 59 |
| TopNMarketCapIndexReweightingLogic | Contract | Contains reweighting logic for TopNMarketCapIndex contract. This index reweighs according to the latest data of assets market capitalizations | 103 |
| TrackedIndex | Contract | Contains initialization and reweighting logic for tracked type of index. Initialization is called only by IndexFactory, it iterates through the _assets param, calculating weight for each asset (based on the relation of its market cap to the total capitalization value) and setting it to weightOf (mapping(address => uint8) from IndexLayout) as well as adding an asset itslelf to the assets (EnumerableSet.AddressSet from IndexLayout). Reweight method validates sender and delegates call to ITrackedIndexReweightingLogic.reweight selector | 56 |
| TrackedIndexReweightingLogic | Contract | Contains reweighting logic for TrackedIndex contract. This index reweighs according to the latest data of assets market capitalizations | 67 |
| UniswapV2PathPriceOracle | Contract | Contains logic for price calculation of asset which doesn't have a pair with a base asset. It uses a list of assets to compose exchange pairs, where first element is input asset and a list of corresponding price oracles for provided path. Inside refreshedAssetPerBaseInUQ and lastAssetPerBaseInUQ methods we iterate through path until getting value for passed _asset param | 53 |
| UniswapV2PriceOracle | Contract | Contains logic for price calculation of asset using Uniswap V2 Pair. Oracle works through base asset which is set in initialize function. It uses UniswapV2OracleLibrary (from uniswap/v2-periphery repo) | 65 |
| vToken | Contract | Contains logic for index's asset management. It uses NAV library to track contract shares between indexes | 141 |
We would like wardens to focus on any core functional logic, boundary case errors or similar issues which could be utilized by an attacker to take funds away from clients who have funds deposited in the protocol. That said any errors may be submitted by wardens for review and potential reward as per the normal issue impact prioritization. Gas optimizations are welcome but not the main focus of this contest and thus at most 10% of the contest reward will be allocated to gas optimizations. For gas optimizations the most important flows are client deposit and withdrawal flows.
If wardens are unclear on which areas to look at or which areas are important please feel free to ask in the contest Discord channel.