|
Message-ID: <f8eed86d66c1d592196c9ce8b9c329e1@smtp.hushmail.com> Date: Sun, 23 Aug 2015 17:15:15 +0200 From: magnum <john.magnum@...hmail.com> To: john-dev@...ts.openwall.com Subject: Re: Formats using non-SIMD SHA2 implementations > I might not have stated my problem clearly... I'll sum it up here: suppose I have a message of length (A + B) and I've already compute the hash of the first A bytes which is H(A); given only H(A) and the remaining B bytes of data, can I compute the hash of the entire message, i.e. H(A + B) ? > > I want to use OpenSSL's SHA function to do this, but I don't see such an interface provided. This is already in use in JtR's SIMD SHA implementation (with the SSEi_RELOAD flag), so I think it's technically doable in OpenSSL. Do I need to hack SHA_CTX somehow? That's easy but unfortunately it's not portable (we're not guaranteed the ctx struct internals, names differs among various libs). A better alternative might be to simply use our SIMD function (with RELOAD like you said) using just one lane. magnum
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.