Re: Question about ctr mode 3des-ede IV len

From: Herbert Xu
Date: Thu Dec 08 2016 - 04:04:45 EST


On Wed, Dec 07, 2016 at 08:43:16PM +0800, Longpeng (Mike) wrote:
> Hi Jussi and Herbert,
>
> I saw serveral des3-ede testcases(in crypto/testmgr.h) has 16-bytes IV, and the
> libgcrypt/nettle/RFC1851 said the IV-len is 8-bytes.
>
> Would you please tell me why these testcases has 16-bytes IV ?

I think they were automatically generated. Only the first eight
bytes are actually used so the IV size is still 8.

Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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