Account Hashing Algorithm Choice

[f-fsantos]

For the server, I want to discuss our options in regards to what password hashing algorithm we should use.
From my point of view we have 3 options:

• Bcrypt
• PBKDF2
• Argon2

Here's an article explaining the differences in a good way: https://security.stackexchange.com/questions/216380/which-is-the-best-password-hashing-algorithm-in-net-core

[frutescens]

Is memory management a major concern of ours?

[f-fsantos]

If you mean total amount of memory available in the system, then yes.

[flx-sta]

The native C# support is a good point in that post. In the end it doesn’t really matter unless we have specific aspects we wanna focus on more. I worked with bcryp in the past but only since it was already in use. If I had to choose I’d go with native which would be PBKDF2 in .NET

[f-fsantos]

Native support is indeed a big point. Although we can always test the validity of the libraries to make it a relatively non-issue.

[frutescens]

OWASP recommends Argon2id
https://cheatsheetseries.owasp.org/cheatsheets/Password_Storage_Cheat_Sheet.html

[flx-sta]

Saving a a click if necessary:

• Use Argon2id with a minimum configuration of 19 MiB of memory, an iteration count of 2, and 1 degree of parallelism.
• If Argon2id is not available, use scrypt with a minimum CPU/memory cost parameter of (2^17), a minimum block size of 8 (1024 bytes), and a parallelization parameter of 1.
• For legacy systems using bcrypt, use a work factor of 10 or more and with a password limit of 72 bytes.
• If FIPS-140 compliance is required, use PBKDF2 with a work factor of 600,000 or more and set with an internal hash function of HMAC-SHA-256.
• Consider using a pepper to provide additional defense in depth (though alone, it provides no additional secure characteristics).

[f-fsantos]

Argon2id is the most recent one, bcrypt is still the recommended one for web applications, and PBKDF2 is natively available.