CMAC

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Jeffrey Walton

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Aug 10, 2008, 11:45:27 PM8/10/08

to Crypto++

Hi All\Wei,

I have a need for validating CMACs. Does Crypto++ offer it under
another name? I've already looked for it under OMAC.

Jeff

http://en.wikipedia.org/wiki/CMAC

Yongce

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Aug 11, 2008, 6:07:26 AM8/11/08

to Crypto++ Users

Hi Jeff,

The class name of CMAC in Crypto++ is CBC_MAC.

Yongce

Jeffrey Walton

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Aug 11, 2008, 1:14:56 PM8/11/08

to Yongce, Crypto++ Users

Hi All/Yongce,

From the Crypto++ source code, CBC_MAC looks like the flawed CBC-MAC
and not the CMAC specified in FIPS 800-38.This is confirmed with the
source code comments:

Compatible with FIPS 113....
Secure only for fixed length messages.
For variable length messages use DMAC.

Unfortunately, looking at the source for DMAC (in dmac.h), it does not
appear that DMAC is an acronym for CMAC...