How do you implement cryptography best practices in your software development process?

1 Choose the right cryptographic algorithms

The first step is to select the appropriate cryptographic algorithms for your use case. There are different types of algorithms, such as symmetric, asymmetric, hashing, or digital signatures, each with their own strengths and weaknesses. You should choose the ones that meet your security requirements, performance goals, and compatibility standards. You should also avoid using outdated or insecure algorithms, such as MD5, SHA-1, or DES, and use the latest and recommended ones, such as AES, SHA-256, or RSA.

2 Use secure random numbers

The second step is to use secure random numbers for generating keys, salts, nonces, or other cryptographic parameters. Random numbers are crucial for ensuring the unpredictability and uniqueness of cryptographic operations. However, not all random numbers are created equal. You should avoid using pseudo-random number generators (PRNGs) that are based on deterministic algorithms or predictable seeds. Instead, you should use cryptographically secure random number generators (CSPRNGs) that are based on physical sources of randomness or cryptographic algorithms.

3 Manage your keys properly

The third step is to manage your keys properly throughout their lifecycle. Keys are the secret ingredients that make cryptography work. They need to be generated, stored, distributed, rotated, and revoked securely and efficiently. You should follow the principle of least privilege and give access to keys only to those who need them. You should also encrypt your keys at rest and in transit, use key management systems (KMS) or hardware security modules (HSM) to store and manage them, and implement key rotation policies to limit their exposure and validity.

4 Validate your inputs and outputs

The fourth step is to validate your inputs and outputs before and after applying cryptography. You should check that your inputs are well-formed, sanitized, and authorized, and that your outputs are consistent, complete, and authenticated. You should also handle any errors or exceptions that may occur during cryptographic operations gracefully and securely. For example, you should never reveal the details of cryptographic errors to unauthorized parties, and you should always log and monitor them for auditing and debugging purposes.

5 Test and review your code

The fifth step is to test and review your code thoroughly and regularly. You should use automated tools and frameworks to perform unit testing, integration testing, and penetration testing on your cryptographic code. You should also use code analysis tools and code review platforms to check for any vulnerabilities, bugs, or bad practices in your code. You should also follow coding standards and guidelines that are specific to cryptography, such as OWASP, NIST, or ISO.

6 Stay updated and informed

The sixth and final step is to stay updated and informed about the latest developments and trends in cryptography. Cryptography is a dynamic and evolving field that constantly faces new challenges and opportunities. You should keep an eye on the latest research, news, and events in cryptography, and learn from the best practices and experiences of other developers and experts. You should also be ready to adapt and update your code and processes as new technologies, standards, or threats emerge.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?