Re: The importance of IVs

From: mobius30 (
Date: 08/27/05

Date: 27 Aug 2005 14:30:37 -0700

Paul Rubin wrote:
>No. There is a class of known weak keys for reduced-round variants.

Yes, I've heard of this, though I don't have any experience with it
yet. From what I understand the weak-key attack has no effect on
16-round Blowfish. As you said, only in reduced-round variants.
However, it would be interesting to code an app that automatically
checks for weak keys after key expansion/generation. I imagine it
would involve logically checking each S-box for twins. However this
would take up more CPU clock cycles, slowing down the app significantly.