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Schneier: We Don't Need SHA-3

Trailrunner7 writes with this excerpt from Threatpost: "For the last five years, NIST, the government body charged with developing new standards for computer security, among other things, has been searching for a new hash function to replace the aging SHA-2 function. Five years is a long time, but this is the federal government and things move at their own pace in Washington, but NIST soon will be announcing the winner from the five finalists that were chosen last year. Despite the problems that have cropped up with some versions of SHA-2 in the past and the long wait for the new function, there doesn't seem to be much in the way of breathless anticipation for this announcement. So much so, in fact, that Bruce Schneier, a co-author of one of the finalists not only isn't hoping that his entry wins, he's hoping that none of them wins. ... It's not because Schneier doesn't think the finalists are worthy of winning. In fact, he says, they're all good and fast and perfectly capable. The problem is, he doesn't think that the world needs a new hash function standard at all. SHA-512, the stronger version of the SHA-2 function that's been in use for more than a decade, is still holding up fine, Schneier said, which was not what cryptographers anticipated would be the case when the SHA-3 competition was conceived. 'I expect SHA-2 to be still acceptable for the foreseeable future. That's the problem. It's not like AES. Everyone knew that DES was dead — and triple-DES was too slow and clunky — and we needed something new. So when AES appeared, people switched as soon as they could. This will be different,' Schneier said via email."

2 of 143 comments (clear)

  1. I have an idea by diamondmagic · · Score: 5, Informative

    How about we link to Schneier's actual blog post? https://www.schneier.com/blog/archives/2012/09/sha-3_will_be_a.html

  2. Re:Too slow? by BCoates · · Score: 5, Informative

    The proper name for these "Slow functions" is Key Derivation Function. They've been around a long time and are what OSes use to protect login credentials and what encrypted archive formats like RAR use.

    Some examples are crypt (obsolete, vulnerable) PBKDF-2 (repeated application of salt-and-hash), bcrypt (repeated rounds of a special extra-slow variant of blowfish), and scrypt (an attempt to defeat GPU and custom hardware attacks by requiring lots of low-latency RAM).

    Single-round salted hash is only a "better than plaintext" hack solution, it's never been the correct way to store passwords.