However, just because the language makes it easier to write secure code doesn’t mean we can let our guard down when it comes to encryption and decryption.

In this article, I’m going to share some tips on how to use Rust’s cryptography library (`ring`) to protect your data from prying eyes. But before we dive into the details, let me remind you that security is not a one-size-fits-all solution. Every application has its own unique requirements and constraints, so it’s essential to understand what level of protection you need and how much effort you’re willing to put in.

Now that we have that out of the way, some best practices for using `ring`:

1. Don’t roll your own crypto (DRYOC) This is a classic mistake that many developers make when they think they can do better than established algorithms and protocols. The truth is, most of us don’t have the expertise or resources to design secure cryptography systems from scratch. Instead, we should rely on proven standards like AES, RSA, and HMAC.

2. Use a key management system Keys are the lifeblood of any encryption scheme, but they can also be a major headache if you don’t have a proper way to manage them. `ring` provides a simple API for generating and storing keys using various formats like PKCS#8 or PEM. However, it’s up to us to ensure that these keys are kept safe from unauthorized access.

3. Avoid hardcoding secrets This is another common mistake that can compromise the security of our applications. Instead of embedding sensitive data directly into our codebase, we should use environment variables or configuration files to store them separately. This way, if someone gains access to our source code, they won’t be able to steal our keys without also having access to these external resources.

4. Use secure randomness Random numbers are essential for generating strong encryption keys and preventing predictable patterns in our data. However, most operating systems provide weak or deterministic sources of entropy that can compromise the security of our applications. To avoid this problem, we should use a cryptographically secure pseudorandom number generator (CSPRNG) like `rand_chacha` instead.

5. Validate input and output Cryptography is not foolproof, and even minor errors in our code can have catastrophic consequences. To prevent these issues, we should validate all inputs and outputs to ensure that they conform to the expected format and size. This way, if someone tries to inject malicious data into our system, it will be rejected before it causes any damage.

6. Test your implementation Finally, we should test our cryptography implementations thoroughly to ensure that they work as intended. `ring` provides a suite of tests for each algorithm and mode, but we can also write our own custom tests to cover specific use cases or edge cases. By doing so, we’ll be able to catch any bugs or vulnerabilities before they cause any harm.