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Hats Finance


Process Quality Review (0.8)

Hats Finance

Final score:96%
Date:30 Mar 2022
Audit Process:version 0.8
PQR Score:96%


Protocol Website:https://hats.finance

Scoring Appendix

The final review score is indicated as a percentage. The percentage is calculated as Achieved Points due to MAX Possible Points. For each element the answer can be either Yes/No or a percentage. For a detailed breakdown of the individual weights of each question, please consult this document.

The blockchain used by this protocol

Very simply, the audit looks for the following declarations from the developer's site. With these declarations, it is reasonable to trust the smart contracts.

  • Here is my smart contract on the blockchain
  • You can see it matches a software repository used to develop the code
  • Here is the documentation that explains what my smart contract does
  • Here are the tests I ran to verify my smart contract
  • Here are the audit(s) performed to review my code by third party experts

This report is for informational purposes only and does not constitute investment advice of any kind, nor does it constitute an offer to provide investment advisory or other services. Nothing in this report shall be considered a solicitation or offer to buy or sell any security, token, future, option or other financial instrument or to offer or provide any investment advice or service to any person in any jurisdiction. Nothing contained in this report constitutes investment advice or offers any opinion with respect to the suitability of any security, and the views expressed in this report should not be taken as advice to buy, sell or hold any security. The information in this report should not be relied upon for the purpose of investing. In preparing the information contained in this report, we have not taken into account the investment needs, objectives and financial circumstances of any particular investor. This information has no regard to the specific investment objectives, financial situation and particular needs of any specific recipient of this information and investments discussed may not be suitable for all investors.

Any views expressed in this report by us were prepared based upon the information available to us at the time such views were written. The views expressed within this report are limited to DeFiSafety and the author and do not reflect those of any additional or third party and are strictly based upon DeFiSafety, its authors, interpretations and evaluation of relevant data. Changed or additional information could cause such views to change. All information is subject to possible correction. Information may quickly become unreliable for various reasons, including changes in market conditions or economic circumstances.

This completed report is copyright (c) DeFiSafety 2023. Permission is given to copy in whole, retaining this copyright label.

Smart Contracts & Team


This section looks at the code deployed on the relevant chain that gets reviewed and its corresponding software repository. The document explaining these questions is here.

1. Are the smart contract addresses easy to find? (%)

Answer: 100%

Contract addresses were found in the front end. In addition, they can be located in the GitBook too.

Percentage Score Guidance:
Clearly labelled and on website, documents or repository, quick to find
Clearly labelled and on website, docs or repo but takes a bit of looking
Addresses in mainnet.json, in discord or sub graph, etc
Address found but labeling not clear or easy to find
Executing addresses could not be found

2. How active is the primary contract? (%)

Answer: 100%

Contract use is frequently over 10 times a day. Given that this is a bug bounty program, this is extremely impressive.

Percentage Score Guidance:
More than 10 transactions a day
More than 10 transactions a week
More than 10 transactions a month
Less than 10 transactions a month
No activity

3. Does the protocol have a public software repository? (Y/N)

Answer: Yes

This protocol uses GitHub.

Score Guidance:
There is a public software repository with the code at a minimum, but also normally test and scripts. Even if the repository was created just to hold the files and has just 1 transaction.
For teams with private repositories.

4. Is there a development history visible? (%)

Answer: 100%

At 166 commits and 46 branches, these developers document their history as frequently as they tip (and even change) their fedoras.

Percentage Score Guidance:
Any one of 100+ commits, 10+branches
Any one of 70+ commits, 7+branches
Any one of 50+ commits, 5+branches
Any one of 30+ commits, 3+branches
Less than 2 branches or less than 30 commits

5. Is the team public (not anonymous)?

Answer: 50

No team members that cross-confirm they are contributing to Hats were found. Some contributors are public, but they do not confirm affiliation.

Score Guidance:
At least two names can be easily found in the protocol's website, documentation or medium. These are then confirmed by the personal websites of the individuals / their linkedin / twitter.
At least one public name can be found to be working on the protocol.
No public team members could be found.



The difference between this and the old link is solely the link.    This section looks at the software documentation. The document explaining these questions is here.

6. Is there a whitepaper? (Y/N)

Answer: Yes

Location: https://docs.hats.finance/

7. Is the protocol's software architecture documented? (Y/N)

Answer: Yes

Hat's software architecture is documented.

Score Guidance:
The documents identify software architecture and contract interaction through any of the following: diagrams, arrows, specific reference to software functions or a written explanation on how smart contracts interact.
Protocols receive a "no" if none of these are included.

8. Does the software documentation fully cover the deployed contracts' source code? (%)

Answer: 100%

There is coverage of deployed contracts by software function documentation.

Percentage Score Guidance:
All contracts and functions documented
Only the major functions documented
79 - 1%
Estimate of the level of software documentation
No software documentation

9. Is it possible to trace the documented software to its implementation in the protocol's source code? (%)

Answer: 60%

There is implied and non-explicit traceability between software documentation and implemented code.

Percentage Score Guidance:
Clear explicit traceability between code and documentation at a requirement level for all code
Clear association between code and documents via non explicit traceability
Documentation lists all the functions and describes their functions
No connection between documentation and code



10. Has the protocol tested their deployed code? (%)

Answer: 100%

Code examples are in the Appendix at the end of this report.. As per the SLOC, there is 303% testing to code (TtC).    This score is guided by the Test to Code ratio (TtC). Generally a good test to code ratio is over 100%. However, the reviewer's best judgement is the final deciding factor.

Percentage Score Guidance:
TtC > 120% Both unit and system test visible
TtC > 80% Both unit and system test visible
TtC < 80% Some tests visible
No tests obvious

11. How covered is the protocol's code? (%)

Answer: 97%

Hats has 97% coverage.

Percentage Score Guidance:
Documented full coverage
99 - 51%
Value of test coverage from documented results
No indication of code coverage but clearly there is a complete set of tests
Some tests evident but not complete
No test for coverage seen

12. Does the protocol provide scripts and instructions to run their tests? (Y/N)

Answer: Yes

Scripts/Instructions location: https://github.com/hats-finance/hats-contracts#check-deployment

Score Guidance:
Scripts and/or instructions to run tests are available in the testing suite
Scripts and/or instructions to run tests are not available in the testing suite

13. Is there a detailed report of the protocol's test results?(%)

Answer: 70%

A code coverage report is evident.

Percentage Score Guidance:
Detailed test report as described below
GitHub code coverage report visible
No test report evident

14. Has the protocol undergone Formal Verification? (Y/N)

Answer: No

This protocol has not undergone formal verification.

Score Guidance:
Formal Verification was performed and the report is readily available
Formal Verification was not performed and/or the report is not readily available.

15. Were the smart contracts deployed to a testnet? (Y/N)

Answer: Yes

Hats has been deployed to a testnet. This could be more clearly documented nevertheless and users could benefit from the testnet addresses for verification.

Score Guidance:
Protocol has proved their tesnet usage by providing the addresses
Protocol has not proved their testnet usage by providing the addresses



This section looks at the 3rd party software audits done. It is explained in this document.

16. Is the protocol sufficiently audited? (%)

Answer: 100%

Hats' is audited. It underwent multiple audits, all of which were before launch.

Percentage Score Guidance:
Multiple Audits performed before deployment and the audit findings are public and implemented or not required
Single audit performed before deployment and audit findings are public and implemented or not required
Audit(s) performed after deployment and no changes required. The Audit report is public.
Code is forked from an already audited protocol and a changelog is provided explaining why forked code was used and what changes were made. This changelog must justify why the changes made do not affect the audit.
Audit(s) performed after deployment and changes are needed but not implemented.
Audit(s) performed are low-quality and do not indicate proper due diligence.
No audit performed
Audit Performed after deployment, existence is public, report is not public OR smart contract address' not found.
Deduct 25% if the audited code is not available for comparison.

17. Is the bounty value acceptably high (%)

Answer: 100%

Hats offers a $250K active bug bounty program. This is more than 10% of the total TVL at time of writing.

Percentage Score Guidance:
Bounty is 10% TVL or at least $1M AND active program (see below)
Bounty is 5% TVL or at least 500k AND active program
Bounty is 5% TVL or at least 500k
Bounty is 100k or over AND active program
Bounty is 100k or over
Bounty is 50k or over AND active program
Bounty is 50k or over
Bug bounty program bounty is less than 50k
No bug bounty program offered / the bug bounty program is dead
An active program means that a third party (such as Immunefi) is actively driving hackers to the site. An inactive program would be static mentions on the docs.

Admin Controls


This section covers the documentation of special access controls for a DeFi protocol. The admin access controls are the contracts that allow updating contracts or coefficients in the protocol. Since these contracts can allow the protocol admins to "change the rules", complete disclosure of capabilities is vital for user's transparency. It is explained in this document.

18. Is the protocol's admin control information easy to find?

Answer: 100%

Admin control information was easy to find.

Percentage Score Guidance:
Admin Controls are clearly labelled and on website, docs or repo, quick to find
Admin Controls are clearly labelled and on website, docs or repo but takes a bit of looking
Admin Control docs are in multiple places and not well labelled
Admin Control docs are in multiple places and not labelled
Admin Control information could not be found

19. Are relevant contracts clearly labelled as upgradeable or immutable? (%)

Answer: 100%

The relevant contracts are clearly identified as immutable or upgradeable.

Percentage Score Guidance:
Both the contract documentation and the smart contract code state that the code is not upgradeable or immutable.
All Contracts are clearly labelled as upgradeable (or not)
Code is immutable but not mentioned anywhere in the documentation
Admin control information could not be found

20. Is the type of smart contract ownership clearly indicated? (%)

Answer: 100%

$HAT holders will be the owners of the protocol. It is currently controlled by a Multisig.

Percentage Score Guidance:
The type of ownership is clearly indicated in their documentation. (OnlyOwner / MultiSig / etc)
The type of ownership is indicated, but only in the code. (OnlyOwner / MultiSig / etc)
Admin Control information could not be found

21. Are the protocol's smart contract change capabilities described? (%)

Answer: 100%

Smart contract change capabilities are identified in this document

Percentage Score Guidance:
The documentation covers the capabilities for change for all smart contracts
The documentation covers the capabilities for change in some, but not all contracts
The documentation does not cover the capabilities for change in any contract

22. Is the protocol's admin control information easy to understand? (%)

Answer: 100%

This information is not in software specific language, aiding user comprehension.

Percentage Score Guidance:
All the contracts are immutable
Description relates to investments safety in clear non-software language
Description all in software-specific language
No admin control information could be found

23. Is there sufficient Pause Control documentation? (%)

Answer: 100%

Hats Finance does not use a pause control. This is explained.

Percentage Score Guidance:
If immutable and no changes possible
If admin control is fully via governance
Robust transaction signing process (7 or more elements)
Adequate transaction signing process (5 or more elements)
Weak transaction signing process (3 or more elements)
No transaction signing process evident
Evidence of audits of signers following the process add 20%

24. Is there sufficient Timelock documentation? (%)

Answer: 100%
Percentage Score Guidance:
Documentation identifies and explains why the protocol does not need a Timelock OR Timelock documentation identifies its duration, which contracts it applies to and justifies this time period.
A Timelock is identified and its duration is specified
A Timelock is identified
No Timelock information was documented

25. Is the Timelock of an adequate length? (Y/N)

Answer: 100%

The timelock is 3 weeks long. This length is the default as set by OpenZeppelin.

Percentage Score Guidance:
Timelock is between 48 hours to 1 week OR justification as to why no Timelock is needed / is outside this length.
Timelock is less than 48 hours or greater than 1 week.
No Timelock information was documented OR no timelock length was identified.



This section goes over the documentation that a protocol may or may not supply about their Oracle usage. Oracles are a fundamental part of DeFi as they are responsible for relaying tons of price data information to thousands of protocols using blockchain technology. Not only are they important for price feeds, but they are also an essential component of transaction verification and security. This is explained in this document.

26. Is the protocol's Oracle sufficiently documented? (%)

Answer: 100

Hats does not use an oracle, as explained here.

Score Guidance:
If it uses one, the Oracle is specified. The contracts dependent on the oracle are identified. Basic software functions are identified (if the protocol provides its own price feed data). Timeframe of price feeds are identified. OR The reason as to why the protocol does not use an Oracle is identified and explained.
The Oracle documentation identifies both source and timeframe, but does not provide additional context regarding smart contracts.
Only the Oracle source is identified.
No oracle is named / no oracle information is documented.

27. Is front running mitigated by this protocol? (Y/N)

Answer: Yes

This protocol documents good front running mitigation techniques. Bounty payouts are impossible to front run thanks to a safety period.

Score Guidance:
The protocol cannot be front run and there is an explanation as to why OR documented front running countermeasures are implemented.
The Oracle documentation identifies both source and timeframe, but does not provide additional context regarding smart contracts.

28. Can flashloan attacks be applied to the protocol, and if so, are those flashloan attack risks mitigated? (Y/N)

Answer: Yes

This protocol cannot undergo flashloan attacks, and this is explained in this location.

Score Guidance:
The protocol's documentation includes information on how they mitigate the possibilities and extents of flash loan attacks.
The protocol's documentation does not include any information regarding the mitigation of flash loan attacks.


1// SPDX-License-Identifier: MIT
2// Disclaimer https://github.com/hats-finance/hats-contracts/blob/main/DISCLAIMER.md
4pragma solidity 0.8.6;
7import "openzeppelin-solidity/contracts/token/ERC20/IERC20.sol";
8import "openzeppelin-solidity/contracts/token/ERC20/utils/SafeERC20.sol";
9import "openzeppelin-solidity/contracts/utils/math/SafeMath.sol";
10import "./HATToken.sol";
11import "openzeppelin-solidity/contracts/security/ReentrancyGuard.sol";
13// Errors:
14// HME01: Pool range is too big
15// HME02: Invalid pool range
16// HME03: Committee not checked in yet
17// HME04: Withdraw: not enough user balance
18// HME05: User amount must be greater than 0
19// HME06: lpToken is already in pool
20contract HATMaster is ReentrancyGuard {
21    using SafeMath for uint256;
22    using SafeERC20 for IERC20;
24    struct UserInfo {
25        uint256 amount;     // The user share of the pool based on the amount of lpToken the user has provided.
26        uint256 rewardDebt; // Reward debt. See explanation below.
27      //
28      // We do some fancy math here. Basically, any point in time, the amount of HATs
29      // entitled to a user but is pending to be distributed is:
30      //
31      //   pending reward = (user.amount * pool.rewardPerShare) - user.rewardDebt
32      //
33      // Whenever a user deposits or withdraws LP tokens to a pool. Here's what happens:
34      //   1. The pool's `rewardPerShare` (and `lastRewardBlock`) gets updated.
35      //   2. User receives the pending reward sent to his/her address.
36      //   3. User's `amount` gets updated.
37      //   4. User's `rewardDebt` gets updated.
38    }
40    struct PoolUpdate {
41        uint256 blockNumber;// update blocknumber
42        uint256 totalAllocPoint; //totalAllocPoint
43    }
45    struct RewardsSplit {
46        //the percentage of the total reward to reward the hacker via vesting contract(claim reported)
47        uint256 hackerVestedReward;
48        //the percentage of the total reward to reward the hacker(claim reported)
49        uint256 hackerReward;
50        // the percentage of the total reward to be sent to the committee
51        uint256 committeeReward;
52        // the percentage of the total reward to be swap to HAT and to be burned
53        uint256 swapAndBurn;
54        // the percentage of the total reward to be swap to HAT and sent to governance
55        uint256 governanceHatReward;
56        // the percentage of the total reward to be swap to HAT and sent to the hacker
57        uint256 hackerHatReward;
58    }
60    // Info of each pool.
61    struct PoolInfo {
62        IERC20 lpToken;
63        uint256 allocPoint;
64        uint256 lastRewardBlock;
65        uint256 rewardPerShare;
66        uint256 totalUsersAmount;
67        uint256 lastProcessedTotalAllocPoint;
68        uint256 balance;
69    }
71    // Info of each pool.
72    struct PoolReward {
73        RewardsSplit rewardsSplit;
74        uint256[]  rewardsLevels;
75        bool committeeCheckIn;
76        uint256 vestingDuration;
77        uint256 vestingPeriods;
78    }
80    HATToken public immutable HAT;
81    uint256 public immutable REWARD_PER_BLOCK;
82    uint256 public immutable START_BLOCK;
83    uint256 public immutable MULTIPLIER_PERIOD;
84    uint256 public constant MULTIPLIERS_LENGTH = 24;
86    // Info of each pool.
87    PoolInfo[] public poolInfo;
88    PoolUpdate[] public globalPoolUpdates;
90    // Reward Multipliers
91    uint256[24] public rewardMultipliers = [4413, 4413, 8825, 7788, 6873, 6065,
92                                            5353, 4724, 4169, 3679, 3247, 2865,
93                                            2528, 2231, 1969, 1738, 1534, 1353,
94                                            1194, 1054, 930, 821, 724, 639];
95    mapping(address => uint256) public poolId1; // poolId1 count from 1, subtraction 1 before using with poolInfo
96    // Info of each user that stakes LP tokens. pid => user address => info
97    mapping (uint256 => mapping (address => UserInfo)) public userInfo;
98    //pid -> PoolReward
99    mapping (uint256=>PoolReward) internal poolsRewards;
101    event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
102    event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
103    event EmergencyWithdraw(address indexed user, uint256 indexed pid, uint256 amount);
104    event SendReward(address indexed user, uint256 indexed pid, uint256 amount, uint256 requestedAmount);
105    event MassUpdatePools(uint256 _fromPid, uint256 _toPid);
107    constructor(
108        HATToken _hat,
109        uint256 _rewardPerBlock,
110        uint256 _startBlock,
111        uint256 _multiplierPeriod
112    // solhint-disable-next-line func-visibility
113    ) {
114        HAT = _hat;
115        REWARD_PER_BLOCK = _rewardPerBlock;
116        START_BLOCK = _startBlock;
117        MULTIPLIER_PERIOD = _multiplierPeriod;
118    }
120  /**
121   * @dev massUpdatePools - Update reward variables for all pools
122   * Be careful of gas spending!
123   * @param _fromPid update pools range from this pool id
124   * @param _toPid update pools range to this pool id
125   */
126    function massUpdatePools(uint256 _fromPid, uint256 _toPid) external {
127        require(_toPid <= poolInfo.length, "HME01");
128        require(_fromPid <= _toPid, "HME02");
129        for (uint256 pid = _fromPid; pid < _toPid; ++pid) {
130            updatePool(pid);
131        }
132        emit MassUpdatePools(_fromPid, _toPid);
133    }
135    function claimReward(uint256 _pid) external {
136        _deposit(_pid, 0);
137    }
139    function updatePool(uint256 _pid) public {
140        PoolInfo storage pool = poolInfo[_pid];
141        uint256 lastRewardBlock = pool.lastRewardBlock;
142        if (block.number <= lastRewardBlock) {
143            return;
144        }
145        uint256 totalUsersAmount = pool.totalUsersAmount;
146        uint256 lastPoolUpdate = globalPoolUpdates.length-1;
147        if (totalUsersAmount == 0) {
148            pool.lastRewardBlock = block.number;
149            pool.lastProcessedTotalAllocPoint = lastPoolUpdate;
150            return;
151        }
152        uint256 reward = calcPoolReward(_pid, lastRewardBlock, lastPoolUpdate);
153        uint256 amountCanMint = HAT.minters(address(this));
154        reward = amountCanMint < reward ? amountCanMint : reward;
155        if (reward > 0) {
156            HAT.mint(address(this), reward);
157        }
158        pool.rewardPerShare = pool.rewardPerShare.add(reward.mul(1e12).div(totalUsersAmount));
159        pool.lastRewardBlock = block.number;
160        pool.lastProcessedTotalAllocPoint = lastPoolUpdate;
161    }
163    /**
164     * @dev getMultiplier - multiply blocks with relevant multiplier for specific range
165     * @param _from range's from block
166     * @param _to range's to block
167     * will revert if from < START_BLOCK or _to < _from
168     */
169    function getMultiplier(uint256 _from, uint256 _to) public view returns (uint256 result) {
170        uint256 i = (_from - START_BLOCK) / MULTIPLIER_PERIOD + 1;
171        for (; i <= MULTIPLIERS_LENGTH; i++) {
172            uint256 endBlock = MULTIPLIER_PERIOD * i + START_BLOCK;
173            if (_to <= endBlock) {
174                break;
175            }
176            result += (endBlock - _from) * rewardMultipliers[i-1];
177            _from = endBlock;
178        }
179        result += (_to - _from) * (i > MULTIPLIERS_LENGTH ? 0 : rewardMultipliers[i-1]);
180    }
182    function getRewardForBlocksRange(uint256 _from, uint256 _to, uint256 _allocPoint, uint256 _totalAllocPoint)
183    public
184    view
185    returns (uint256 reward) {
186        if (_totalAllocPoint > 0) {
187            reward = getMultiplier(_from, _to).mul(REWARD_PER_BLOCK).mul(_allocPoint).div(_totalAllocPoint).div(100);
188        }
189    }
191    /**
192     * @dev calcPoolReward -
193     * calculate rewards for a pool by iterating over the history of totalAllocPoints updates.
194     * and sum up all rewards periods from pool.lastRewardBlock till current block number.
195     * @param _pid pool id
196     * @param _from block starting calculation
197     * @param _lastPoolUpdate lastPoolUpdate
198     * @return reward
199     */
200    function calcPoolReward(uint256 _pid, uint256 _from, uint256 _lastPoolUpdate) public view returns(uint256 reward) {
201        uint256 poolAllocPoint = poolInfo[_pid].allocPoint;
202        uint256 i = poolInfo[_pid].lastProcessedTotalAllocPoint;
203        for (; i < _lastPoolUpdate; i++) {
204            uint256 nextUpdateBlock = globalPoolUpdates[i+1].blockNumber;
205            reward =
206            reward.add(getRewardForBlocksRange(_from,
207                                            nextUpdateBlock,
208                                            poolAllocPoint,
209                                            globalPoolUpdates[i].totalAllocPoint));
210            _from = nextUpdateBlock;
211        }
212        return reward.add(getRewardForBlocksRange(_from,
213                                                block.number,
214                                                poolAllocPoint,
215                                                globalPoolUpdates[i].totalAllocPoint));
216    }