Learning about every nitty-gritty of smart contracts and writing them in several programming languages takes work. And this is a significant task that we should also pay attention to. So, getting an independent audit is a big yes for every serious blockchain-based project.
This blog will walk you through the twelve steps to robust blockchain security. With them, every smart contract auditing is complete! Just like our auditors do, make sure to follow them.
Let us get started.
The Smart Contract Security Audit Process
Developing good smart contracts without flaws is a great skill for every auditor. However, the process involves a strict methodology and few complexes yet well-defined steps. Are you curious to know what those steps are? Worry not; we will discuss them in detail.
Let us now break down this auditing process into smaller steps and see what it takes the auditors to provide top-notch security to the users.
Source code lock-down
Blockchain project owners deliver their smart contracts to the auditors in numerous ways to get them audited. One of them is giving auditors a truffled project in a compressed archive. Another way is sending them a link to a source code repository and providing the auditors with contracts that have verified source code and are already deployed on a test network.
The auditors ensure the audited file’s integrity can be confirmed post-audit. This stage is crucial because projects employ audits to show their users that the code operates as stated and written, in addition to using them to validate security.
Project Familiarization
It is imperative to get yourself familiarized with the smart contract’s purpose before getting into the minute details of the code. So, in this phase, the auditors ask projects to give them all the available documentation.
Reviewing the preliminary code
Now it’s the perfect time to dwell deeper into the code—one of the most important steps here, the auditors to go through the entire code carefully. They gain some knowledge about the main design, check the libraries used, and verify the test coverage.
Most of the auditors, by this stage, get a basic understanding of the general quality of the design.
Analyzing the static code
The next step in the smart contract auditing process is diligently analyzing the static code. This analysis provides useful insights into the projects they otherwise miss during development. For this, the auditors also use various tools to automate the process and easily find vulnerabilities.
Analyzing the quality of the code
Next, the smart contract security auditors analyze the code’s quality. This step ensures that all the best security practices for auditing and general software engineering guidelines, including avoiding replicated code, commenting, and function visibility, have been strictly followed.
Analyzing the known vulnerabilities
This is the step that a majority of people associate with the process of smart contract audit. The auditors perform a line-by-line code analysis against these vulnerabilities:
- Reentrancy
- Transaction ordering assumptions
- Variable shadowing
- Incorrect cryptographic signature validation
- Storage pointer exploits
- Insecure random number generation
- Over and underflows
- Timestamp dependencies
- Potential denial of service attacks
- Block gas limit issues
Depending upon the bug’s severity, the auditors label it as critical, major, or minor.
Analyzing the Functionality
Some common errors that auditors find include formula errors and rounding errors due to integer arithmetic etc. The cause for these errors is the fault in permission management.
Live Testing
In terms of exploitability or correct functioning in edge cases, many questions we get in the previous steps still need to be answered. Depending on the complex issues, auditors often deploy the contracts on a local network to run their tests on them.
Checking the efficiency (Gas usage)
After the auditors are assured about the security and functionality of the smart contracts, the next step is to check their efficiency. This is first done automatically using gas estimation followed by line-by-line manual code analysis.
Initial Audit report
Now that the auditors are through with all the previous steps, they produce a written audit report and deliver it to the clients. This report contains all the issues they found in the smart contract and a list of additional recommendations to eliminate the vulnerabilities.
Reviewing the round one fixes
Getting a smart contract free from even a single bug is very rare. So, there are two rounds of the audit process. In the first round, the auditors include all the issues in the initial audit report and give the clients a chance to fix them and present a new version of the code.
Then the client and the auditor communicate several times. They review each fix and see whether it resolves the issues and has no other unwanted side effects.
Final audit report
Once all the fixes are done and reviewed, the auditors prepare the final audit report. This has all the issues, fixes and the final verdict clearly explained.
Smart Contract Audit- A Comprehensive Process
As the procedure mentioned above shows, the auditing process adheres to a rigid approach. Smart contract audits demand time and resources as a result of this. Thus, the auditors must not be contacted a few days before the launch of the blockchain project; they should get ample time to go through the source code and make it vulnerability free.
Who wouldn’t want an error-free and bug-free smart contract? Then, you ought to let the auditors do their work properly!