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- Starts February 16, 2022 00:00 UTC
- Ends February 18, 2022 23:59 UTC
Note: The brownie configuration and tests are are out of scope. testhelpers is out of scope as well.
Setup guide, can be found here. make sure its interest-model-redesign branch
The full repository and the commit that is used for the scope of this audit is located here. The scope of this audit is the changes found in the following diff here, made as a result of a previous audit from another firm.
The protocol's core bZxProtocol contract is deployed which is a custom moduled proxy, and the Modules can be found in contract/modules folder.
For every underlying asset there is an IToken contract which is the tokenized lending pool.
The highest financial risk lies in the new interest accruing mechanism that was developed. The previous version used a rollover mechanism using rollover function. An EOA could trigger once every 28 days the rollover function for the loan to pay for the accrued interest. Interest was taken from collateral and paid upfront for 28 days. This mechanism has been replaced by dynamic interest rate that is added to the principal of loan. The new contract that is being used to handle this in the protocol is InterestHandler.sol. It is important to make sure that all modules are secure and all edge cases are accounted for appropriately, including cases where iTokens are burned minted traded and transfered.
Next critical change is dex selector which is a new feature that allows users to select a dex and provide the necessary payload to execute the swap for the margin trade on the dex chosen. DexRecords will serve as the resolver for the deployed swap implementations for the chain. Each swap implementation on DexRecords will have an unique ID that is used to retrieve the address. The swapsImpl variable found in State.sol has been re-purposed to be set to the address of the deployed DexRecords contract. payload with details for the swap is passed externally and great care should be taken into verifying those details onchain.
Another change is we added small fee for the flash loans check payFlashBorrowFees use cases
Total : 60 files changed, 3995 insertions(+), 3752 deletions(-)
git diff development --numstat
| Added Lines | Deleted Lines | File |
|---|---|---|
| 7 | 9 | brownie-config.yaml |
| 2 | 2 | contracts/adapters/TokenRegistry.sol |
| 7 | 8 | contracts/connectors/loantoken/LoanTokenBase.sol |
| 0 | 561 | contracts/connectors/loantoken/LoanTokenLogicDai.sol |
| 176 | 318 | contracts/connectors/loantoken/LoanTokenLogicStandard.sol |
| 0 | 109 | contracts/connectors/loantoken/LoanTokenLogicWeth_Arbitrum.sol |
| 21 | 1 | contracts/connectors/loantoken/LoanTokenSettings.sol |
| 33 | 24 | contracts/connectors/loantoken/LoanTokenSettingsLowerAdmin.sol |
| 16 | 0 | contracts/connectors/loantoken/StorageExtension.sol |
| 6 | 6 | contracts/core/Constants.sol |
| 15 | 2 | contracts/core/State.sol |
| 5 | 5 | contracts/core/objects/LenderInterestStruct.sol |
| 3 | 3 | contracts/core/objects/LoanInterestStruct.sol |
| 25 | 0 | contracts/events/InterestRateEvents.sol |
| 2 | 1 | contracts/farm/BuyBackAndBurn.sol |
| 2 | 2 | contracts/helpers/DAppHelper.sol |
| 2 | 2 | contracts/helpers/HelperImpl.sol |
| 27 | 0 | contracts/interfaces/ICurvedInterestRate.sol |
| 14 | 0 | contracts/interfaces/IDexRecords.sol |
| 9 | 1 | contracts/interfaces/ILoanPool.sol |
| 11 | 0 | contracts/interfaces/IUniswapQuoter.sol |
| 1 | 0 | contracts/interfaces/IUniswapV3SwapRouter.sol |
| 0 | 11 | contracts/interfaces/IaeWETH.sol |
| 21 | 96 | contracts/mixins/FeesHelper.sol |
| 5 | 0 | contracts/mixins/Flags.sol |
| 157 | 0 | contracts/mixins/InterestHandler.sol |
| 0 | 77 | contracts/mixins/InterestUser.sol |
| 0 | 137 | contracts/mixins/VaultController_Arbitrum.sol |
| 57 | 0 | contracts/modules/FlashBorrowFees/FlashBorrowFeesHelper.sol |
| 6 | 27 | contracts/modules/LoanClosings/LoanClosings.sol |
| 57 | 373 | contracts/modules/LoanClosings/LoanClosingsBase.sol |
| 65 | 375 | contracts/modules/LoanClosings/LoanClosingsBase_Arbitrum.sol |
| 5 | 26 | contracts/modules/LoanClosings/LoanClosings_Arbitrum.sol |
| 0 | 123 | contracts/modules/LoanMaintenance/LoanCleanup.sol |
| 13 | 308 | contracts/modules/LoanMaintenance/LoanMaintenance.sol |
| 45 | 1 | contracts/modules/LoanMaintenance/LoanMaintenance_2.sol |
| 22 | 311 | contracts/modules/LoanMaintenance/LoanMaintenance_Arbitrum.sol |
| 32 | 152 | contracts/modules/LoanOpenings/LoanOpenings.sol |
| 71 | 3 | contracts/modules/LoanSettings/LoanSettings.sol |
| 7 | 3 | contracts/modules/ProtocolSettings/ProtocolSettings.sol |
| 5 | 4 | contracts/modules/SwapsExternal/SwapsExternal.sol |
| 2 | 2 | contracts/stakingv2/modules/StakeUnstake.sol |
| 25 | 0 | contracts/swaps/DexRecords.sol |
| 21 | 21 | contracts/swaps/ISwapsImpl.sol |
| 106 | 46 | contracts/swaps/SwapsUser.sol |
| 68 | 46 | contracts/swaps/connectors/SwapsImplUniswapV2_ARBITRUM.sol |
| 26 | 11 | contracts/swaps/connectors/SwapsImplUniswapV2_BSC.sol |
| 73 | 54 | contracts/swaps/connectors/SwapsImplUniswapV2_ETH.sol |
| 70 | 48 | contracts/swaps/connectors/SwapsImplUniswapV2_POLYGON.sol |
| 363 | 0 | contracts/swaps/connectors/SwapsImplUniswapV3_ETH.sol |
| 457 | 0 | contracts/testhelpers/TWAI.sol |
| 59 | 0 | contracts/utils/CurvedInterestRate.sol |
| 73 | 28 | interfaces/IBZx.sol |
| 15 | 3 | interfaces/IToken |
| 1 | 0 | package.json |
| 18 | 38 | scripts/add-token/add-itoken-arbitrum.py |
| 94 | 0 | tests/test_selector.py |
| 600 | 0 | testsarbitrum/interest-rate-model/test_InterestRate.py |
| 523 | 0 | testspolygon/interest-rate-model/test_InterestRate.py |
| 449 | 374 | yarn.lock |
pip3 install eth-brownie==1.17.2
npm install
brownie compile