Reply To: 8-byte CMAC

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Re: 8-byte CMAC

2. August 2017 at 14:24

TapLinx Support
Hi Claudio,

Section 3.1.3.1 of AN1823 shows the switch to AV2 mode. In step 5 a “reduced” CMAC is used. The CMAC is a 16 byte value and for step 5 only the odd bytes are used to perform an 8 byte vector like:

CMAC(C8E7F707455E194F015E7F3503000000) = A509E6108ADBDB49CC831A02680DE82E
Step 5 takes odd bytes: 09 10 DB 49 83 02 0D 2E

Regards,
The TapLinx team
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