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Re: Plan B for fixing 5.8.2 binary API



According to Nicholas Clark:
> Whereas if we adopt plan A, and all that we get wrong is that it's not a
> very strong defence against hashing attacks, we are no worse off than
> 5.8.0

IMO, high-quality hash seeding is more important than XS binary
compatibility.  Seeding is a security feature, and security trumps
just about anything else[*].  If we can't make any plan for seeding
*with* bincompat work right -- though I'm confident that we can --
then we should break the binary API in a way that requires
recompilation of XSs that use PERL_HASH().  Weak hash seeding is
simply Not OK.  IMO.

On the other hand, I don't have enough crypto(ish) experience to
either write or approve of a hashing algorithm, especially one that
tries to sequeeze every last bit of entropy out of small data.  So:

> IIRC the paper had exploit code. I think it's time to play with that.

If you feel confident in your ability to come up with a good hash,
please be my guest.  (No sarcasm.)  But Plan B *is* within my skill
set; to my eyes, it's looking like a lower risk than Plan A.

[*] "A Smith & Wesson beats four aces."
-- 
Chip Salzenberg               - a.k.a. -               <chip@pobox.com>
"I wanted to play hopscotch with the impenetrable mystery of existence,
    but he stepped in a wormhole and had to go in early."  // MST3K



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