Any reason I shouldn t be salting and hashing before putting through bCrypt

Question

I'm working on implementing password security and have a question regarding the order of operations when using bcrypt. Some suggest salting and hashing the password first before passing it through bcrypt, while others recommend letting bcrypt handle everything.

Would adding an additional salt before bcrypt provide any real security benefits, or does it interfere with bcrypt’s built-in security mechanisms? Could this approach introduce unnecessary complexity or even weaken the security of the hashing process?

Answer 1

When implementing password security with bcrypt, it's important to understand how salting and hashing are handled to ensure optimal security without introducing unnecessary complexity.

Bcrypt's Built-in Salting Mechanism

Bcrypt is designed to handle salting internally. When you hash a password using bcrypt, it automatically generates a unique salt for each password, combines it with the password, and then processes this combination through its hashing algorithm. The resulting hash includes both the salt and the hashed password, eliminating the need for manual salting.

Potential Issues with Additional Pre-Hashing and Salting

Introducing an additional salting or hashing step before passing the password to bcrypt can have unintended consequences:

1. Redundancy: Since bcrypt already salts passwords uniquely, adding another layer of salting doesn't provide significant additional security benefits.

2. Complexity: Implementing extra steps increases the complexity of your password handling process, which can lead to potential errors and maintenance challenges.

3. Security Risks: Pre-hashing passwords before bcrypt can introduce vulnerabilities. For instance, if the pre-hashing algorithm isn't as secure or if it's implemented incorrectly, it could weaken the overall security of the password storage mechanism.

Best Practices to Ensure Robust Password Security

• Rely on Bcrypt's Internal Mechanism: Trust bcrypt to handle salting and hashing. Its design ensures that each password is salted uniquely, providing strong protection against attacks like rainbow tables.

• Avoid Pre-Hashing: Refrain from hashing the password before passing it to bcrypt, as this can introduce vulnerabilities and doesn't offer significant security advantages.

• Use a Pepper for Enhanced Security: For added security, consider using a "pepper," which is a secret value added to the password before hashing. Unlike a salt, a pepper is not stored in the database and remains consistent across all passwords. This approach can provide an additional layer of security, especially if the database is compromised.