ImpactVault smart contract - Arab Bank Switzerland Stake2Care Project

Intro

The ImpactVault smart contract is an ERC 4626 Vault, which is used to donate the revenues of a value-accruing token to a NGO. In the present case, users will deposit Lido ST-ETH and the staking yield will be distributed to Doctors Without Borders (MSF).

On Deposit of stETH, the user receives MSF-ETH. Withdrawals are instantaneous and handled in stETH only.

Deposits into the ImpactVault are further mediated by the LidoImpactVaultDepositor to convert-and-deposit ETH as well. When converting ETH, the user can choose which proportion of the obtained stETH is to be deposited into the Impact Vault while the remainder is sent back to them.

The depositor has the option of staking the obtained msfETH through the charityEscrow contract and receive MSF-Karma rewards. The charityEscrow implements a modified voting-escrow mechanism with several distinct features:

• Upon staking, users receive upfront a bonus in a transferrable ERC-20 token, the "MSF-Karma".
• The Bonus increases quadratically with the time locked.
• Users may unstake before the unlock if they burn MSF-Karma tokens.
• MSF-Karma tokens can be directly purchased from the smart contract.

A precise whitepaper on the charity-escrow logic is available here.

Getting started

• install npm i
• build contract using solidity : npm run build
• run tests npm run test
• deploy npx hardhat run scripts/deploy.ts --network mainnet

Audits

You can find all audit reports under the audits folder:

• BlackPaper
• HHK
• HHK (CharityEscrow)

Deployment Addresses

Contracts have been deployed to Ethereum Mainnet:

• msfETH (ImpactVault): 0x34f4e4b964a3e648723aE71AF5550FbC85E2e534
• ImpactVaultDepositor: 0x24fA1BaE144Bd97aF2875AE782299B6549726437
• MSF-Karma: 0x9ec579a11d0d9a866f4910bfeb6234e77a02cd5f
• Charity Escrow: 0x0b63AeFCf391122878f5b05CF345b9D1702064c4

Official Website

Stake2Care official website.

Tests

Impact Vault

• ✔ Deployer has correct stETH balance at test start and can set stETH accrual
• ✔ Only deployer can set stETH accrual and call the mint function
• ✔ Anyone can submit by sending ETH directly to the stETH contract
• ✔ Deployer has correct msfETH balance at test start
• ✔ Depositor can Mint Asset by sending ETH to receive() of lidoImpactVaultDepositor and then Withdraw
• ✔ Depositor can Mint Asset by sending stETH via depositAsset() function of lidoImpactVaultDepositor
• ✔ Depositor can Mint Asset by sending ETH to depositETH() of lidoImpactVaultDepositor with a depositProportion of 80%
• ✔ depositToken() should revert with NotImplementedError
• ✔ Only owner can set AutoCollectThreshold
• ✔ Depositor can mint shares by sending ETH via mint() of impactVault and then withdraw
• ✔ collectDonations is timelocked for 3 days after second deposit
• ✔ collectDonations does not update pending surplus if it is below autoCollectThreshold
• ✔ collectDonations can be called with custom minimalTransfer to bypass minimalCollectAmount

MSFPoint and CharityEscrow

MSFPoint

• ✔ MSFP deployment should set the right name and symbol (1185ms)
• ✔ Only MINTER_ROLE could mint (90ms)
• ✔ Only DEFAULT_ADMIN_ROLE could recoverERC20 (88ms)

CharityEscrow deployment

• ✔ CharityEscrow deployment should be possible only if baseEarnRate_ and yearlyBonus_ below their max value (143ms)

Charity escrow usage

• ✔ Only owner could recoverERC20, but only if token is different from MSF-STETH
• ✔ Only owner could setPointPrice, but only if new price is not too low nor too high, unless if zero (46ms)
• ✔ Only owner could setEarnStructure, but only within allowed bounds
• ✔ InvestorA locks his MSF-STETH into CharityEscrow for 3 years
• ✔ View functions lockReward and baseRewardDelta return expected values
• ✔ totalSupply returns ImpactVault Balance
• ✔ The transfer, transferFrom and approve functions exist for CharityEscrow but are not implemented
• ✔ user can buy Points at pointPrice (42ms)
• ✔ user cannot buy Points when pointPrice is 0
• ✔ InvestorA can unlock his MSF-STETH after the end of the lock period (46ms)
• ✔ InvestorA can increaseLock with additional funds and duration
• ✔ InvestorA can increaseLock with just additional funds (42ms)
• ✔ InvestorA can increaseLock with just additional duration
• ✔ InvestorA cannot increaseLock if newEffectiveLockDuration is maximumLockDuration or below minimumLockDuration
• ✔ InvestorA can decreaseLock by just decreasing duration (38ms)
• ✔ InvestorA can decreaseLock by just decreasing amount (43ms)
• ✔ When increasing Lock, due Time Reward stays similar (51ms)
• ✔ decreaseLock is equivalent to an unlock, after lock duration ends
• ✔ decreaseLock does an unlock, if newEffectiveLockDuration is null if decrease exceeds duration (41ms)
• ✔ decreaseLock reduces all lockedBalance if newLockBalance is null or if decrease exceeds balance
• ✔ decreaseLock reverts if new values are below minimums but non-zero

·--------------------------------------------------------|---------------------------|--------------|-----------------------------·
|                  Solc version: 0.8.19                  ·  Optimizer enabled: true  ·  Runs: 1000  ·  Block limit: 30000000 gas  │
·························································|···························|··············|······························
|  Methods                                                                                                                        │
·····························|···························|·············|·············|··············|···············|··············
|  Contract                  ·  Method                   ·  Min        ·  Max        ·  Avg         ·  # calls      ·  usd (avg)  │
·····························|···························|·············|·············|··············|···············|··············
|  CharityEscrow             ·  buyPoints                ·          -  ·          -  ·       89850  ·            1  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  CharityEscrow             ·  decreaseLock             ·      37924  ·      77438  ·       64182  ·            8  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  CharityEscrow             ·  increaseLock             ·      55044  ·     146811  ·      121511  ·           20  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  CharityEscrow             ·  recoverERC20             ·          -  ·          -  ·       62807  ·            1  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  CharityEscrow             ·  setEarnStructure         ·          -  ·          -  ·       31072  ·            1  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  CharityEscrow             ·  setPointPrice            ·      25359  ·      47300  ·       32079  ·            4  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  CharityEscrow             ·  transferOwnership        ·      28036  ·      47936  ·       37986  ·            2  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  CharityEscrow             ·  unLock                   ·          -  ·          -  ·       54156  ·            1  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  ImpactVault               ·  approve                  ·          -  ·          -  ·       46713  ·           13  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  ImpactVault               ·  collectDonations         ·          -  ·          -  ·       38088  ·            1  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  ImpactVault               ·  deposit                  ·      85825  ·     115249  ·      111188  ·           31  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  ImpactVault               ·  mint                     ·      68770  ·      76294  ·       72532  ·            4  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  ImpactVault               ·  redeem                   ·          -  ·          -  ·       94719  ·            2  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  ImpactVault               ·  setAutoCollectThreshold  ·      47731  ·      47755  ·       47747  ·            6  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  ImpactVault               ·  transfer                 ·      46994  ·      47006  ·       47000  ·            2  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  ImpactVault               ·  withdraw                 ·          -  ·          -  ·       94785  ·            2  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  LidoImpactVaultDepositor  ·  depositAsset             ·          -  ·          -  ·       95510  ·            2  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  LidoImpactVaultDepositor  ·  depositETH               ·          -  ·          -  ·      126445  ·            3  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  MSFPoint                  ·  approve                  ·      46657  ·      46669  ·       46662  ·            5  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  MSFPoint                  ·  grantRole                ·          -  ·          -  ·       51615  ·            3  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  MSFPoint                  ·  mint                     ·          -  ·          -  ·       70912  ·            1  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  MSFPoint                  ·  recoverERC20             ·          -  ·          -  ·       62775  ·            1  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  SmartAccount              ·  executeBatch             ·          -  ·          -  ·       37064  ·            1  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  TestStETH                 ·  approve                  ·      46668  ·      46680  ·       46673  ·           35  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  TestStETH                 ·  changeAccrual            ·          -  ·          -  ·       28856  ·           16  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  TestStETH                 ·  mint                     ·      73003  ·      73027  ·       73020  ·           30  ·          -  │
·····························|···························|·············|·············|··············|···············|··············
|  Deployments                                           ·                                          ·  % of limit   ·             │
·························································|·············|·············|··············|···············|··············
|  CharityEscrow                                         ·    2432401  ·    2432569  ·     2432485  ·        8.1 %  ·          -  │
·························································|·············|·············|··············|···············|··············
|  ImpactVault                                           ·    1977889  ·    1977913  ·     1977912  ·        6.6 %  ·          -  │
·························································|·············|·············|··············|···············|··············
|  LidoImpactVaultDepositor                              ·          -  ·          -  ·      716156  ·        2.4 %  ·          -  │
·························································|·············|·············|··············|···············|··············
|  MSFPoint                                              ·          -  ·          -  ·     1549720  ·        5.2 %  ·          -  │
·························································|·············|·············|··············|···············|··············
|  SmartAccount                                          ·          -  ·          -  ·      525501  ·        1.8 %  ·          -  │
·························································|·············|·············|··············|···············|··············
|  TestStETH                                             ·          -  ·          -  ·     1086007  ·        3.6 %  ·          -  │
·--------------------------------------------------------|-------------|-------------|--------------|---------------|-------------·

  39 passing (4s)

Coverage

-------------------------------|----------|----------|----------|----------|----------------|
File                           |  % Stmts | % Branch |  % Funcs |  % Lines |Uncovered Lines |
-------------------------------|----------|----------|----------|----------|----------------|
 src/                          |    91.43 |    89.42 |    83.33 |    91.15 |                |
  CharityEscrow.sol            |      100 |      100 |    90.91 |    98.39 |        198,203 |
  ImpactVault.sol              |      100 |      100 |      100 |      100 |                |
  ImpactVaultDepositor.sol     |    77.78 |      100 |      100 |    77.78 |108,109,110,111 |
  LidoImpactVaultDepositor.sol |      100 |      100 |      100 |      100 |                |
  MSFPoint.sol                 |      100 |      100 |      100 |      100 |                |
  StEth.sol                    |        0 |        0 |        0 |        0 |... 40,44,45,49 |
  testStEth.sol                |       75 |     62.5 |    85.71 |    83.33 |          38,39 |
 src/intf/                     |      100 |      100 |      100 |      100 |                |
  ICharityEscrow.sol           |      100 |      100 |      100 |      100 |                |
  IImpactVault.sol             |      100 |      100 |      100 |      100 |                |
  IImpactVaultDepositor.sol    |      100 |      100 |      100 |      100 |                |
  IMSFPoint.sol                |      100 |      100 |      100 |      100 |                |
 src/test/                     |      100 |       50 |      100 |      100 |                |
  SmartAccount.sol             |      100 |       50 |      100 |      100 |                |
-------------------------------|----------|----------|----------|----------|----------------|
All files                      |    91.67 |    87.96 |    83.87 |     91.3 |                |
-------------------------------|----------|----------|----------|----------|----------------|