P
P
PQ Reviews
Search…
0.7
C.R.E.A.M v2 Process Quality Review
Score: 86%

Overview

This is a C.R.E.A.M Process Quality Review completed on October 7th 2021. It was performed using the Process Review process (version 0.7.3) and is documented here. The review was performed by Nic of DeFiSafety. Check out our Telegram.
The final score of the review is 86%, a PASS. The breakdown of the scoring is in Scoring Appendix. For our purposes, a pass is 70%.

Summary of the Process

Very simply, the review looks for the following declarations from the developer's site. With these declarations, it is reasonable to trust the smart contracts.
  • Here are my smart contracts on the blockchain
  • Here is the documentation that explains what my smart contracts do
  • Here are the tests I ran to verify my smart contract
  • Here are the audit(s) performed on my code by third party experts
  • Here are the admin controls and strategies

Disclaimer

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.

Chain

This section indicates the blockchains used by this protocol. This report covers all of the blockchains upon which the protocol is deployed.
Chain: Ethereum, Binance Smart Chain
Guidance: Ethereum Binance Smart Chain Polygon Avalanche Terra Celo Arbitrum Solana

Code and Team

This section looks at the code deployed on the Mainnet that gets reviewed and its corresponding software repository. The document explaining these questions is here. This review will answer the following questions:
1) Are the executing code addresses readily available? (%) 2) Is the code actively being used? (%) 3) Is there a public software repository? (Y/N) 4) Is there a development history visible? (%) 5) Is the team public (not anonymous)? (Y/N)

1) Are the executing code addresses readily available? (%)

Answer: 100%
They are available at website https://docs.cream.finance/smart-contract-address, as indicated in the Appendix.
Guidance: 100% Clearly labelled and on website, docs or repo, 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) Is the code actively being used? (%)

Answer: 100%
Activity is over 10 transactions a day on contract Unitroller.sol, as indicated in the Appendix.

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) Is there a public software repository? (Y/N)

Answer: Yes
Is there 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, it gets a "Yes". For teams with private repositories, this answer is "No".

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

Answer: 100%
With 287 commits and 18 branches, C.R.E.A.M 's main contract repository has a robust development history.
This metric checks if the software repository demonstrates a strong steady history. This is normally demonstrated by commits, branches and releases in a software repository. A healthy history demonstrates a history of more than a month (at a minimum).
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)? (Y/N)

Answer: Yes
For a "Yes" in this question, the real names of some team members must be public on the website or other documentation (LinkedIn, etc). If the team is anonymous, then this question is a "No".

Documentation

This section looks at the software documentation. The document explaining these questions is here.
Required questions are;
6) Is there a whitepaper? (Y/N) 7) Are the basic software functions documented? (Y/N) 8) Does the software function documentation fully (100%) cover the deployed contracts? (%) 9) Are there sufficiently detailed comments for all functions within the deployed contract code (%) 10) Is it possible to trace from software documentation to the implementation in code (%)

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

Answer: Yes

7) Are the basic software functions documented? (Y/N)

Answer: Yes
C.R.E.A.M has basic function documentation in the "Developer" section of their documentation, as well as a very in-depth document explaining their changes on the forked Compound code in their GitHub repository.

8) Does the software function documentation fully (100%) cover the deployed contracts? (%)

Answer: 100%
Since C.R.E.A.M is a direct fork of Compound while also being transparent about it by directly linking it in their documentation in addition to all the change logs, they essentially cover all of the deployed contracts.
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) Are there sufficiently detailed comments for all functions within the deployed contract code (%)

Answer: 73%
Code examples are in the Appendix. As per the SLOC, there is 73% commenting to code (CtC).
The Comments to Code (CtC) ratio is the primary metric for this score.
Guidance: 100% CtC > 100 Useful comments consistently on all code 90-70% CtC > 70 Useful comment on most code 60-20% CtC > 20 Some useful commenting 0% CtC < 20 No useful commenting

How to improve this score

This score can improve by adding comments to the deployed code such that it comprehensively covers the code. For guidance, refer to the SecurEth Software Requirements.

10) Is it possible to trace from software documentation to the implementation in code (%)

Answer: 60%
There is a clear association between code and documents via non explicit traceability at https://docs.cream.finance/developer/crtokens.
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

How to improve this score:

This score can improve by adding traceability from documentation to code such that it is clear where each outlined function is coded in the source code. For reference, check the SecurEth guidelines on traceability.

Testing

This section looks at the software testing available. It is explained in this document. This section answers the following questions;
11) Full test suite (Covers all the deployed code) (%) 12) Code coverage (Covers all the deployed lines of code, or explains misses) (%) 13) Scripts and instructions to run the tests (Y/N) 14) Report of the results (%) 15) Formal Verification test done (%) 16) Stress Testing environment (%)

11) Is there a Full test suite? (%)

Answer: 100%
Code examples are in the Appendix. As per the SLOC, there is 172% 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 reviewers best judgement is the final deciding factor.
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

How to improve this score:

This score can improved by adding tests to fully cover the code. Document what is covered by traceability or test results in the software repository.

12) Code coverage (Covers all the deployed lines of code, or explains misses) (%)

Answer: 50%
There is no evidence of any C.R.E.A.M code coverage, however there is a reasonably complete set of tests.
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 reasonably complete set of tests 30% Some tests evident but not complete 0% No test for coverage seen

How to improve this score:

This score can improved by adding tests that achieve full code coverage. A clear report and scripts in the software repository will guarantee a high score.

13) Scripts and instructions to run the tests (Y/N)

Answer: Yes

14) Report of the results (%)

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

How to improve this score

Add a report with the results. The test scripts should generate the report or elements of it.

15) Formal Verification test done (%)

Answer: 0%
There is no evidence of a C.R.E.A.M Formal Verification test.

16) Stress Testing environment (%)

Answer: 100%
There is clear testnet usage at https://testnet.cream.finance/.

Security

This section looks at the 3rd party software audits done. It is explained in this document. This section answers the following questions;
17) Did 3rd Party audits take place? (%) 18) Is the bounty value acceptably high?

17) Did 3rd Party audits take place? (%)

Answer: 90%
C.R.E.A.M v2 underwent an audit by Trail of Bits pre-deployment. The report can be found at https://github.com/CreamFi/compound-protocol/tree/cream-v2/audits.
Guidance: 100% Multiple Audits performed before deployment and results public and implemented or not required 90% Single audit performed before deployment and results public and implemented or not required 70% Audit(s) performed after deployment and no changes required. Audit report is public
50% Audit(s) performed after deployment and changes needed but not implemented 20% No audit performed 0% Audit Performed after deployment, existence is public, report is not public and no improvements deployed OR smart contract address' not found, (where question 1 is 0%)
Deduct 25% if code is in a private repo and no note from auditors that audit is applicable to deployed code

18) Is the bounty value acceptably high (%)

Answer: 100%
Bug Bounty program can be found at https://immunefi.com/bounty/creamfinance/.
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
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.

Access 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. The questions this section asks are as follow;
19) Can a user clearly and quickly find the status of the admin controls? 20) Is the information clear and complete? 21) Is the information in non-technical terms that pertain to the investments? 22) Is there Pause Control documentation including records of tests?

19) Can a user clearly and quickly find the status of the access controls (%)

Answer: 70%
There is governance information available at https://docs.cream.finance/listing-committee and https://docs.cream.finance/icecream/icecream-tokenomics#long-term-staking-cream-can-vote, but it certainly takes a bit of searching via the search bar.
Guidance: 100% Clearly labelled and on website, docs or repo, quick to find 70% Clearly labelled and on website, docs or repo but takes a bit of looking 40% Access control docs in multiple places and not well labelled 20% Access control docs in multiple places and not labelled 0% Admin Control information could not be found

20) Is the information clear and complete (%)

Answer: 45%
a) All contracts are clearly labelled as upgradeable (or not) -- 15% -- No contracts are explicitly labelled as upgradeable or immutable, but it is inferred by the voting process.
b) The type of ownership is clearly indicated (OnlyOwner / MultiSig / Defined Roles) -- 15% -- Staking contract permissions are described at https://docs.cream.finance/eth2/why-stake-in-ethereum-2.0#risks-you-should-know-before-staking.
c) The capabilities for change in the contracts are described -- 15% -- No capabilities for change in contracts are explicitly detailed, but are slightly inferred by the light proposal parameters at https://docs.cream.finance/listing-committee.
Guidance: All the contracts are immutable -- 100% OR
a) All contracts are clearly labelled as upgradeable (or not) -- 30% AND b) The type of ownership is clearly indicated (OnlyOwner / MultiSig / Defined Roles) -- 30% AND c) The capabilities for change in the contracts are described -- 30%

How to improve this score:

Create a document that covers the items described above. An example is enclosed.

21) Is the information in non-technical terms that pertain to the investments (%)

Answer: 90%
Information regarding staking contract investment safety can be found at https://docs.cream.finance/eth2/why-stake-in-ethereum-2.0.
Guidance: 100% All the contracts are immutable 90% Description relates to investments safety and updates in clear, complete non-software l language 30% Description all in software specific language 0% No admin control information could not be found

How to improve this score:

Create a document that covers the items described above in plain language that investors can understand. An example is enclosed.

22) Is there Pause Control documentation including records of tests (%)

Answer: 40%
C.R.E.A.M uses the same pauseGuardian as Compound. This can be viewed in detail at https://github.com/CreamFi/compound-protocol/blob/master/contracts/Comptroller.sol.
Guidance: 100% All the contracts are immutable or no pause control needed and this is explained OR 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

How to improve this score:

Create a document that covers the items described above in plain language that investors can understand. An example is enclosed.

Appendices

Author Details

The author of this review is Rex of DeFi Safety.
Email : [email protected] Twitter : @defisafety
I started with Ethereum just before the DAO and that was a wonderful education. It showed the importance of code quality. The second Parity hack also showed the importance of good process. Here my aviation background offers some value. Aerospace knows how to make reliable code using quality processes.
I was coaxed to go to EthDenver 2018 and there I started SecuEth.org with Bryant and Roman. We created guidelines on good processes for blockchain code development. We got EthFoundation funding to assist in their development.
Process Quality Reviews are an extension of the SecurEth guidelines that will further increase the quality processes in Solidity and Vyper development.
DeFiSafety is my full time gig and we are working on funding vehicles for a permanent staff.

Scoring Appendix

Executing Code Appendix

Code Used Appendix

Example Code Appendix

1
/**
2
* @title Compound's Comptroller Contract
3
* @author Compound (modified by Cream)
4
*/
5
contract Comptroller is ComptrollerV1Storage, ComptrollerInterface, ComptrollerErrorReporter, Exponential {
6
/// @notice Emitted when an admin supports a market
7
event MarketListed(CToken cToken);
8
9
/// @notice Emitted when an admin delists a market
10
event MarketDelisted(CToken cToken);
11
12
/// @notice Emitted when an account enters a market
13
event MarketEntered(CToken cToken, address account);
14
15
/// @notice Emitted when an account exits a market
16
event MarketExited(CToken cToken, address account);
17
18
/// @notice Emitted when close factor is changed by admin
19
event NewCloseFactor(uint256 oldCloseFactorMantissa, uint256 newCloseFactorMantissa);
20
21
/// @notice Emitted when a collateral factor is changed by admin
22
event NewCollateralFactor(CToken cToken, uint256 oldCollateralFactorMantissa, uint256 newCollateralFactorMantissa);
23
24
/// @notice Emitted when liquidation incentive is changed by admin
25
event NewLiquidationIncentive(uint256 oldLiquidationIncentiveMantissa, uint256 newLiquidationIncentiveMantissa);
26
27
/// @notice Emitted when price oracle is changed
28
event NewPriceOracle(PriceOracle oldPriceOracle, PriceOracle newPriceOracle);
29
30
/// @notice Emitted when pause guardian is changed
31
event NewPauseGuardian(address oldPauseGuardian, address newPauseGuardian);
32
33
/// @notice Emitted when liquidity mining module is changed
34
event NewLiquidityMining(address oldLiquidityMining, address newLiquidityMining);
35
36
/// @notice Emitted when an action is paused globally
37
event ActionPaused(string action, bool pauseState);
38
39
/// @notice Emitted when an action is paused on a market
40
event ActionPaused(CToken cToken, string action, bool pauseState);
41
42
/// @notice Emitted when borrow cap for a cToken is changed
43
event NewBorrowCap(CToken indexed cToken, uint256 newBorrowCap);
44
45
/// @notice Emitted when borrow cap guardian is changed
46
event NewBorrowCapGuardian(address oldBorrowCapGuardian, address newBorrowCapGuardian);
47
48
/// @notice Emitted when supply cap for a cToken is changed
49
event NewSupplyCap(CToken indexed cToken, uint256 newSupplyCap);
50
51
/// @notice Emitted when supply cap guardian is changed
52
event NewSupplyCapGuardian(address oldSupplyCapGuardian, address newSupplyCapGuardian);
53
54
/// @notice Emitted when protocol's credit limit has changed
55
event CreditLimitChanged(address protocol, uint256 creditLimit);
56
57
/// @notice Emitted when cToken version is changed
58
event NewCTokenVersion(CToken cToken, Version oldVersion, Version newVersion);
59
60
// No collateralFactorMantissa may exceed this value
61
uint256 internal constant collateralFactorMaxMantissa = 0.9e18; // 0.9
62
63
constructor() public {
64
admin = msg.sender;
65
}
66
67
/*** Assets You Are In ***/
68
69
/**
70
* @notice Returns the assets an account has entered
71
* @param account The address of the account to pull assets for
72
* @return A dynamic list with the assets the account has entered
73
*/
74
function getAssetsIn(address account) external view returns (CToken[] memory) {
75
CToken[] memory assetsIn = accountAssets[account];
76
77
return assetsIn;
78
}
79
80
/**
81
* @notice Returns whether the given account is entered in the given asset
82
* @param account The address of the account to check
83
* @param cToken The cToken to check
84
* @return True if the account is in the asset, otherwise false.
85
*/
86
function checkMembership(address account, CToken cToken) external view returns (bool) {
87
return markets[address(cToken)].accountMembership[account];
88
}
89
90
/**
91
* @notice Add assets to be included in account liquidity calculation
92
* @param cTokens The list of addresses of the cToken markets to be enabled
93
* @return Success indicator for whether each corresponding market was entered
94
*/
95
function enterMarkets(address[] memory cTokens) public returns (uint256[] memory) {
96
uint256 len = cTokens.length;
97
98
uint256[] memory results = new uint256[](len);
99
for (uint256 i = 0; i < len; i++) {
100
CToken cToken = CToken(cTokens[i]);
101
102
results[i] = uint256(addToMarketInternal(cToken, msg.sender));
103
}
104
105
return results;
106
}
107
108
/**
109
* @notice Add the market to the borrower's "assets in" for liquidity calculations
110
* @param cToken The market to enter
111
* @param borrower The address of the account to modify
112
* @return Success indicator for whether the market was entered
113
*/
114
function addToMarketInternal(CToken cToken, address borrower) internal returns (Error) {
115
Market storage marketToJoin = markets[address(cToken)];
116
117
if (!marketToJoin.isListed) {
118
// market is not listed, cannot join
119
return Error.MARKET_NOT_LISTED;
120
}
121
122
if (marketToJoin.version == Version.COLLATERALCAP) {
123
// register collateral for the borrower if the token is CollateralCap version.
124
CCollateralCapErc20Interface(address(cToken)).registerCollateral(borrower);
125
}
126
127
if (marketToJoin.accountMembership[borrower] == true) {
128
// already joined
129
return Error.NO_ERROR;
130
}
131
132
// survived the gauntlet, add to list
133
// NOTE: we store these somewhat redundantly as a significant optimization
134
// this avoids having to iterate through the list for the most common use cases
135
/ that is, only when we need to perform liquidity checks
136
/ and not whenever we want to check if an account is in a particular market
137
marketToJoin.accountMembership[borrower] = true;
138
accountAssets[borrower].push(cToken);
139
140
emit MarketEntered(cToken, borrower);
141
142
return Error.NO_ERROR;
143
Copied!

SLOC Appendix

Solidity Contracts

Language
Files
Lines
Blanks
Comments
Code
Complexity
Solidity
42
14997
2044
5454
7499
1084
Comments to Code 5454/7499 = 73%

Javascript Tests

Language
Files
Lines
Blanks
Comments
Code
Complexity
JavaScript
77
16612
2465
1254
12893
425
Tests to Code 12893/7499 = 172%
Last modified 1mo ago