I'm fairly knowledgable with encryption, and processes, but I need to make sure that the BCrypt for NodeJS module I want to use, specifically the Random Bit Generator BCrypt uses, is compatible with NIST SP 800-90A R1. There's a lot of very specific requirements, so I want to make sure I'm meeting them. The NIST requirements allow for Hash, HMAC, and CTR based Deterministic Random Bit Generators(DRBG), which I believe BCrypt meets, but I don't see where BCrypt specifically calls out in detail their DRBG in any of their documentation. Perhaps I don't fully understand how this works and it's obvious to some other people, but can someone help me understand this qualification. I'm specifically looking at BCrypt's RBG and it's qualification under this NIST document, and not BCrypt as a whole and it's acceptance by NIST.
When NIST calls out RBG as a hash function as acceptable, it appears BCrypt meets these requirements, but I may be confusing BCrypts encryption, with it's Random Bit Generator.
Conceptually, the random numbers generated by bcrypt are used as salt.
Salt does not have to be crypographically strong—it is not a requirment.
Salt only has to be different.
Now, in practice, most implementations of bcrypt are likely to use a cryptographically strong random number generator (provided by the platform that they're running on).
But now you're asking about the internal implementation details of one particular implementation of bcrypt. That implementation makes no promises about the strength of the RNG it uses. It doesn't even guarantee that they will continue to use the same RNG source between versions - or between platforms.
node.bcrypt.jscould decide tomorrow to switch to sequential UUIDs as their source for salt, rather than a OS-provided secure RNG. If your system was depending on their internal RNG for its security, you will suddenly find yourself in a world of hurt.If you need a randomness, you need to ensure it yourself.