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

From: Longpeng (Mike)
Date: Thu Dec 08 2016 - 06:30:17 EST


Hi Jussi,

On 2016/12/7 21:15, Jussi Kivilinna wrote:

> Hello,
>
> 07.12.2016, 14:43, Longpeng (Mike) kirjoitti:
>> 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 ?
>
> Because I used same tool to create test-vectors which I had previously used to create AES/Camellia/Serpent/Twofish test-vectors. So, I must have forgotten to change 16-byte IV generation to 8 bytes and thus those testcases in crypto/testmgr.h have wrong length. The extra trailing 8 bytes are not used and can be removed.
>


Thank you very much. :)

> -Jussi
>
>>
>> Thank you. :)
>>
>
> .
>


--
Regards,
Longpeng(Mike)