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JustLend

46%

Process Quality Review (0.8)

JustLend

Final score:46%
Date:27 Jun 2022
Audit Process:version 0.8
Author:Ryoma
PQR Score:46%

FAIL

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
Tron
#QuestionAnswer
82%
1.100%
2.40%
3.Yes
4.0%
5.100
73%
6.Yes
7.Yes
8.50%
9.60%
0%
10.0%
11.0%
12.No
13.0%
14.No
15.No
43%
16.50%
17.0%
57%
18.100%
19.0%
20.100%
21.50%
22.100%
23.0%
24.60%
25.50%
25%
26.50%
27.No
28.No
Total:46%

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 2021. Permission is given to copy in whole, retaining this copyright label.

Smart Contracts & Team

82%

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%

JustLend's smart contract addresses can be found in their GitHub repository.

Percentage Score Guidance:
100%
Clearly labelled and on website, documents or repository, quick to find
70%
Clearly labelled and on website, docs or repo but takes a bit of looking
40%
Addresses in mainnet.json, in discord or sub graph, etc
20%
Address found but labeling not clear or easy to find
0%
Executing addresses could not be found

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

Answer: 40%

JustLend's GovernorAlpha smart contract recorded more than 10 transactions in the last month, but failed to pass the 10 transactions in the last week mark. The protocol therefore earns 40%. A screenshot of the TRONscan can be found in the appendix. There are no contracts relating to lending / borrowing their repository, making us unable to award higher marks here.

Percentage Score Guidance:
100%
More than 10 transactions a day
70%
More than 10 transactions a week
40%
More than 10 transactions a month
10%
Less than 10 transactions a month
0%
No activity

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

Answer: Yes

JustLend's software repository can be found here.

Score Guidance:
Yes
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.
No
For teams with private repositories.

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

Answer: 0%

The protocol's justlend-protocol shows 9 commits and 2 branches, which demonstrates poor development history. This earns the protocol no marks.

Percentage Score Guidance:
100%
Any one of 100+ commits, 10+branches
70%
Any one of 70+ commits, 7+branches
50%
Any one of 50+ commits, 5+branches
30%
Any one of 30+ commits, 3+branches
0%
Less than 2 branches or less than 30 commits

5. Is the team public (not anonymous)?

Answer: 100

JustLend's team can be found publicly on their LinkedIn page. A screenshot of the team page can be found in the appendix.

Score Guidance:
100%
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.
50%
At least one public name can be found to be working on the protocol.
0%
No public team members could be found.

Documentation

73%

This section looks at the software documentation. The document explaining these questions is here.

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

Answer: Yes

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

Answer: Yes

This protocol's software architecture can be found in the third segment of the whitepaper: Architecture of JustLend Protocol. See the question above for the whitepaper link.

Score Guidance:
Yes
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.
No
Protocols receive a "no" if none of these are included.

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

Answer: 50%

As there is a documentation related to partial deployed contracts' documentation in the Contracts section of the protocol's whitepaper but no code associated to the documentation explaining those functions, the protocol receives 50% on this question.

Percentage Score Guidance:
100%
All contracts and functions documented
80%
Only the major functions documented
79 - 1%
Estimate of the level of software documentation
0%
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 implicit traceability to the documented software as each smart contract files are covered within the README.md of the justlend-protocol repository.

Percentage Score Guidance:
100%
Clear explicit traceability between code and documentation at a requirement level for all code
60%
Clear association between code and documents via non explicit traceability
40%
Documentation lists all the functions and describes their functions
0%
No connection between documentation and code

Testing

0%

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

Answer: 0%

There is no evidence of code deployment testing in the protocol's Github repository.

Percentage Score Guidance:
100%
TtC > 120% Both unit and system test visible
80%
TtC > 80% Both unit and system test visible
40%
TtC < 80% Some tests visible
0%
No tests obvious

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

Answer: 0%

There is no code coverage documentation available on JustLend.

Percentage Score Guidance:
100%
Documented full coverage
99 - 51%
Value of test coverage from documented results
50%
No indication of code coverage but clearly there is a complete set of tests
30%
Some tests evident but not complete
0%
No test for coverage seen

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

Answer: No

There are no scripts or instructions provided for JustLend's testsuite.

Score Guidance:
Yes
Scripts and/or instructions to run tests are available in the testing suite
No
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: 0%

There are no detailed reports of the protocol's test results.

Percentage Score Guidance:
100%
Detailed test report as described below
70%
GitHub code coverage report visible
0%
No test report evident

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

Answer: No

JustLend has not undergone Formal Verification.

Score Guidance:
Yes
Formal Verification was performed and the report is readily available
No
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: No

There is no evidence of testnet deployment for JustLend's protocol.

Score Guidance:
Yes
Protocol has proved their tesnet usage by providing the addresses
No
Protocol has not proved their testnet usage by providing the addresses

Security

43%

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

16. Is the protocol sufficiently audited? (%)

Answer: 50%

JustLend has undergone 1 audit with CertiK, which was performed post-launch with partial implementation of changes and recommendations. Because of that, the protocol earns a 50%.

Percentage Score Guidance:
100%
Multiple Audits performed before deployment and the audit findings are public and implemented or not required
90%
Single audit performed before deployment and audit findings are public and implemented or not required
70%
Audit(s) performed after deployment and no changes required. The Audit report is public.
65%
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.
50%
Audit(s) performed after deployment and changes are needed but not implemented.
30%
Audit(s) performed are low-quality and do not indicate proper due diligence.
20%
No audit performed
0%
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: 0%

There is no bug bounty available for JustLend.

Percentage Score Guidance:
100%
Bounty is 10% TVL or at least $1M AND active program (see below)
90%
Bounty is 5% TVL or at least 500k AND active program
80%
Bounty is 5% TVL or at least 500k
70%
Bounty is 100k or over AND active program
60%
Bounty is 100k or over
50%
Bounty is 50k or over AND active program
40%
Bounty is 50k or over
20%
Bug bounty program bounty is less than 50k
0%
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

57%

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 can be found in the 3.7 Governance segment of JustLend's whitepaper.

Percentage Score Guidance:
100%
Admin Controls are clearly labelled and on website, docs or repo, quick to find
70%
Admin Controls are clearly labelled and on website, docs or repo but takes a bit of looking
40%
Admin Control docs are in multiple places and not well labelled
20%
Admin Control docs are in multiple places and not labelled
0%
Admin Control information could not be found

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

Answer: 0%

The relevant contracts are not identified as immutable / upgradeable.

Percentage Score Guidance:
100%
Both the contract documentation and the smart contract code state that the code is not upgradeable or immutable.
80%
All Contracts are clearly labelled as upgradeable (or not)
50%
Code is immutable but not mentioned anywhere in the documentation
0%
Admin control information could not be found

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

Answer: 100%

There is indication of ownership in JustLend's documentation: it is in the hands of JST holders.

Percentage Score Guidance:
100%
The type of ownership is clearly indicated in their documentation. (OnlyOwner / MultiSig / etc)
50%
The type of ownership is indicated, but only in the code. (OnlyOwner / MultiSig / etc)
0%
Admin Control information could not be found

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

Answer: 50%

Admin capabilities are listed in the Governance segment of the whitepaper. However, there is no mention of change capabilities for all smart contracts, which earns the protocol a 50%.

Percentage Score Guidance:
100%
The documentation covers the capabilities for change for all smart contracts
50%
The documentation covers the capabilities for change in some, but not all contracts
0%
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%

Admin control information can be easily understood and is written in non-software specific language.

Percentage Score Guidance:
100%
All the contracts are immutable
90%
Description relates to investments safety in clear non-software language
30%
Description all in software-specific language
0%
No admin control information could be found

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

Answer: 0%

There is no pause control documentation for the protocol.

Percentage Score Guidance:
100%
Pause control(s) are clearly documented and there is records of at least one test within 3 months
80%
Pause control(s) explained clearly but no evidence of regular tests
40%
Pause controls mentioned with no detail on capability or tests
0%
Pause control not documented or explained

24. Is there sufficient Timelock documentation? (%)

Answer: 60%

A timelock.sol contract can be found in the GitHub repository which displays the duration in the code. The protocol therefore gets 60% on this question.

Percentage Score Guidance:
100%
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.
60%
A Timelock is identified and its duration is specified
30%
A Timelock is identified
0%
No Timelock information was documented

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

Answer: 50%

The minimum delay for the timelock is 2 days, maximum delay being 30 days with a grace period of 14 days. Since the maximum timelock goes beyond 1 week, the protocol scores 50% on this question.

Percentage Score Guidance:
100%
Timelock is between 48 hours to 1 week OR justification as to why no Timelock is needed / is outside this length.
50%
Timelock is less than 48 hours or greater than 1 week.
0%
No Timelock information was documented OR no timelock length was identified.

Oracles

25%

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. These questions are explained in this document.

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

Answer: 50%

JustLend's Oracle usage is documented in its whitepaper at the section 3.5 ["Price Oracle"]https://www.justlend.link/docs/justlend_whitepaper_en.pdf). Because only the oracle source (JustSwap) is identified, the protocol earns 50%. Identifying which smart contracts are affected and what the timeframe is would allow the protocol to earn 100% on this score.

Percentage Score Guidance:
100%
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.
75%
The Oracle documentation identifies both source and timeframe, but does not provide additional context regarding smart contracts.
50%
Only the Oracle source is identified.
0%
No oracle is named / no oracle information is documented.

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

Answer: No

JustLend mentions "smooth mechanisms" to avoid risks and greater volatility of prices, however this does not provide enough documentation to prove front running mitigation.

Score Guidance:
Yes
The protocol cannot be front run and there is an explanation as to why OR documented front running countermeasures are implemented.
No
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: No

There is no flashloan attack mitigation technique documented for JustLend.

Score Guidance:
Yes
The protocol's documentation includes information on how they mitigate the possibilities and extents of flash loan attacks.
No
The protocol's documentation does not include any information regarding the mitigation of flash loan attacks.

Appendices

1pragma solidity ^0.5.12;
2
3import "./CToken.sol";
4
5/**
6 * @title Compound's CErc20 Contract
7 * @notice CTokens which wrap an EIP-20 underlying
8 * @author Compound
9 */
10contract CErc20 is CToken, CErc20Interface {
11
12    address constant USDTAddr = 0xa614f803B6FD780986A42c78Ec9c7f77e6DeD13C;// nile:0xECa9bC828A3005B9a3b909f2cc5c2a54794DE05F  mainnet:0xa614f803B6FD780986A42c78Ec9c7f77e6DeD13C
13
14    /**
15     * @notice Initialize the new money market
16     * @param underlying_ The address of the underlying asset
17     * @param comptroller_ The address of the Comptroller
18     * @param interestRateModel_ The address of the interest rate model
19     * @param initialExchangeRateMantissa_ The initial exchange rate, scaled by 1e18
20     * @param name_ ERC-20 name of this token
21     * @param symbol_ ERC-20 symbol of this token
22     * @param decimals_ ERC-20 decimal precision of this token
23     */
24    function initialize(address underlying_,
25                        ComptrollerInterface comptroller_,
26                        InterestRateModel interestRateModel_,
27                        uint initialExchangeRateMantissa_,
28                        string memory name_,
29                        string memory symbol_,
30                        uint8 decimals_,
31                        uint256 newReserveFactorMantissa_) public {
32        // CToken initialize does the bulk of the work
33        super.initialize(comptroller_, interestRateModel_, initialExchangeRateMantissa_, name_, symbol_, decimals_, newReserveFactorMantissa_);
34
35        // Set underlying and sanity check it
36        underlying = underlying_;
37        EIP20Interface(underlying).totalSupply();
38    }
39
40    /*** User Interface ***/
41
42    /**
43     * @notice Sender supplies assets into the market and receives cTokens in exchange
44     * @dev Accrues interest whether or not the operation succeeds, unless reverted
45     * @param mintAmount The amount of the underlying asset to supply
46     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
47     */
48    function mint(uint mintAmount) external returns (uint) {
49        (uint err,) = mintInternal(mintAmount);
50        return err;
51    }
52
53    /**
54     * @notice Sender redeems cTokens in exchange for the underlying asset
55     * @dev Accrues interest whether or not the operation succeeds, unless reverted
56     * @param redeemTokens The number of cTokens to redeem into underlying
57     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
58     */
59    function redeem(uint redeemTokens) external returns (uint) {
60        return redeemInternal(redeemTokens);
61    }
62
63    /**
64     * @notice Sender redeems cTokens in exchange for a specified amount of underlying asset
65     * @dev Accrues interest whether or not the operation succeeds, unless reverted
66     * @param redeemAmount The amount of underlying to redeem
67     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
68     */
69    function redeemUnderlying(uint redeemAmount) external returns (uint) {
70        return redeemUnderlyingInternal(redeemAmount);
71    }
72
73    /**
74      * @notice Sender borrows assets from the protocol to their own address
75      * @param borrowAmount The amount of the underlying asset to borrow
76      * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
77      */
78    function borrow(uint borrowAmount) external returns (uint) {
79        return borrowInternal(borrowAmount);
80    }
81
82    /**
83     * @notice Sender repays their own borrow
84     * @param repayAmount The amount to repay
85     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
86     */
87    function repayBorrow(uint repayAmount) external returns (uint) {
88        (uint err,) = repayBorrowInternal(repayAmount);
89        return err;
90    }
91
92    /**
93     * @notice Sender repays a borrow belonging to borrower
94     * @param borrower the account with the debt being payed off
95     * @param repayAmount The amount to repay
96     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
97     */
98    function repayBorrowBehalf(address borrower, uint repayAmount) external returns (uint) {
99        (uint err,) = repayBorrowBehalfInternal(borrower, repayAmount);
100        return err;
101    }
102
103    /**
104     * @notice The sender liquidates the borrowers collateral.
105     *  The collateral seized is transferred to the liquidator.
106     * @param borrower The borrower of this cToken to be liquidated
107     * @param repayAmount The amount of the underlying borrowed asset to repay
108     * @param cTokenCollateral The market in which to seize collateral from the borrower
109     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
110     */
111    function liquidateBorrow(address borrower, uint repayAmount, CTokenInterface cTokenCollateral) external returns (uint) {
112        (uint err,) = liquidateBorrowInternal(borrower, repayAmount, cTokenCollateral);
113        return err;
114    }
115
116    /**
117     * @notice The sender adds to reserves.
118     * @param addAmount The amount fo underlying token to add as reserves
119     * @return uint 0=success, otherwise a failure (see ErrorReporter.sol for details)
120     */
121    function _addReserves(uint addAmount) external returns (uint) {
122        return _addReservesInternal(addAmount);
123    }
124
125    /*** Safe Token ***/
126
127    /**
128     * @notice Gets balance of this contract in terms of the underlying
129     * @dev This excludes the value of the current message, if any
130     * @return The quantity of underlying tokens owned by this contract
131     */
132    function getCashPrior() internal view returns (uint) {
133        EIP20Interface token = EIP20Interface(underlying);
134        return token.balanceOf(address(this));
135    }
136
137    /**
138     * @dev Similar to EIP20 transfer, except it handles a False result from `transferFrom` and reverts in that case.
139     *      This will revert due to insufficient balance or insufficient allowance.
140     *      This function returns the actual amount received,
141     *      which may be less than `amount` if there is a fee attached to the transfer.
142     *
143     *      Note: This wrapper safely handles non-standard ERC-20 tokens that do not return a value.
144     *            See here: https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
145     */
146    function doTransferIn(address from, uint amount) internal returns (uint) {
147        EIP20NonStandardInterface token = EIP20NonStandardInterface(underlying);
148        uint balanceBefore = EIP20Interface(underlying).balanceOf(address(this));
149        token.transferFrom(from, address(this), amount);
150
151        bool success;
152        assembly {
153            switch returndatasize()
154                case 0 {                       // This is a non-standard ERC-20
155                    success := not(0)          // set success to true
156                }
157                case 32 {                      // This is a compliant ERC-20
158                    returndatacopy(0, 0, 32)
159                    success := mload(0)        // Set `success = returndata` of external call
160                }
161                default {                      // This is an excessively non-compliant ERC-20, revert.
162                    revert(0, 0)
163                }
164        }
165        require(success, "TOKEN_TRANSFER_IN_FAILED");
166
167        // Calculate the amount that was *actually* transferred
168        uint balanceAfter = EIP20Interface(underlying).balanceOf(address(this));
169        require(balanceAfter >= balanceBefore, "TOKEN_TRANSFER_IN_OVERFLOW");
170        return balanceAfter - balanceBefore;   // underflow already checked above, just subtract
171    }
172
173    /**
174     * @dev Similar to EIP20 transfer, except it handles a False success from `transfer` and returns an explanatory
175     *      error code rather than reverting. If caller has not called checked protocol's balance, this may revert due to
176     *      insufficient cash held in this contract. If caller has checked protocol's balance prior to this call, and verified
177     *      it is >= amount, this should not revert in normal conditions.
178     *
179     *      Note: This wrapper safely handles non-standard ERC-20 tokens that do not return a value.
180     *            See here: https://medium.com/coinmonks/missing-return-value-bug-at-least-130-tokens-affected-d67bf08521ca
181     */
182    function doTransferOut(address payable to, uint amount) internal {
183        EIP20NonStandardInterface token = EIP20NonStandardInterface(underlying);
184        token.transfer(to, amount);
185
186        bool success;
187        if(address(token) == USDTAddr){
188            return;
189        }
190        assembly {
191            switch returndatasize()
192                case 0 {                      // This is a non-standard ERC-20
193                    success := not(0)          // set success to true
194                }
195                case 32 {                     // This is a complaint ERC-20
196                    returndatacopy(0, 0, 32)
197                    success := mload(0)        // Set `success = returndata` of external call
198                }
199                default {                     // This is an excessively non-compliant ERC-20, revert.
200                    revert(0, 0)
201                }
202            }
203        require(success, "TOKEN_TRANSFER_OUT_FAILED");
N/A