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First the theoretical explanations: Integrity and authenticity are different goals to achieve, but both are achieved (for symmetric encryption) with a MAC. You should probably be using encrypt-than-MAC or an authenticated cipher unless you have very good reasons not to. No blanket statements can be made though. HMAC: HMAC is a often used construct. It ...


3

First, terms: A MAC is a generic term for a class of cryptographic primitives. It's in the same category as "hash" or "PRNG." HMAC is a particular construction that, combined with a suitable cryptographic hash, gives a secure MAC function (it can also be used to generically refer to any HMAC algorithm, since HMAC is secure with pretty much any standard hash, ...


2

First, don't roll your own crypto. Second, why would you want to use CBC-MAC, if you have GMAC (GCM-mode) and CMAC and even better HMAC? (all of which are better than CBC-MAC) Third, don't try to fix problems that have been fixed. (see second) Fourth, I'm not aware of this construction being standardized and I'd doubt it has been. (see points 1 to 3) ...


1

@gammatester gave most of the answer, but he didn't address the last question: would this make HMAC the only NIST approved MAC? No, as of right now, the block cipher-based Message Authentication Codes CMAC and GMAC are also approved. In addition, if you use the approved mode CCM with a empty message, that's effectively a MAC over the Additional ...


1

You will find a list of Approved security functions (message authentication among them) here on the NIST website (FIPS 140-2 Annex A: Approved Security Functions): http://csrc.nist.gov/publications/fips/fips140-2/fips1402annexa.pdf Interestingly in this document #1 (Triple-DES) references FIPS 113, which leads me to believe the method in FIPS 113 is valid ...


1

The NIST site http://csrc.nist.gov/publications/PubsFIPSArch.html lists FIPS 113 as Withdrawn: Sep 2008. The Federal Register https://www.federalregister.gov/articles/2005/07/15/05-13992/proposed-withdrawal-of-ten-10-federal-information-processing-standards-fips gives a reason: FIPS 113, Computer Data Authentication, specifies an algorithm for ...



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