3 ms·
Wait. Why are they repeating SHA-256 10N times? What's the point? (I know about key derivation and why you want it to be slow. I'm wondering why they're doing t
by lvh 16y ago
Wait. Why are they repeating SHA-256 10N times? What's the point? (I know about key derivation and why you want it to be slow. I'm wondering why they're doing that, when the article already mentions PBKDF2. Why it's PBKDF2 and not scrypt or bcrypt is probably about buzzword compliance.)
- derobert 16y agoRepeating a SHA-256 (or other hash) many times is essentially what PBKDF2 is. Though since 100 million SHA-256/sec is apparently doable on GPUs, even with 100,000 rounds, you currently need at least an 8-character random password to be secure from someone attacking without much budget.
- lvh 16y agoYes, I know -- the question stands: why would you have both of these concurrently in the same system? Either you want a KDF, or you don't want a KDF -- pick one, and don't start reinventing your own (potentially poorly), please :-(