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* Question about ctr mode 3des-ede IV len
@ 2016-12-07 12:43 Longpeng (Mike)
  2016-12-07 13:15 ` Jussi Kivilinna
  2016-12-08  9:04 ` Herbert Xu
  0 siblings, 2 replies; 5+ messages in thread
From: Longpeng (Mike) @ 2016-12-07 12:43 UTC (permalink / raw)
  To: jussi.kivilinna, jussi.kivilinna, herbert
  Cc: Gonglei, Zhoujian (jay, Euler), Wubin (H), longpeng2,
	linux-kernel

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 ?

Thank you. :)

-- 
Regards,
Longpeng(Mike)

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Question about ctr mode 3des-ede IV len
  2016-12-07 12:43 Question about ctr mode 3des-ede IV len Longpeng (Mike)
@ 2016-12-07 13:15 ` Jussi Kivilinna
  2016-12-08 11:29   ` Longpeng (Mike)
  2016-12-08  9:04 ` Herbert Xu
  1 sibling, 1 reply; 5+ messages in thread
From: Jussi Kivilinna @ 2016-12-07 13:15 UTC (permalink / raw)
  To: Longpeng (Mike), jussi.kivilinna, herbert
  Cc: Gonglei, Zhoujian (jay, Euler), Wubin (H), linux-kernel

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.

-Jussi

> 
> Thank you. :)
> 

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Question about ctr mode 3des-ede IV len
  2016-12-07 12:43 Question about ctr mode 3des-ede IV len Longpeng (Mike)
  2016-12-07 13:15 ` Jussi Kivilinna
@ 2016-12-08  9:04 ` Herbert Xu
  2016-12-08  9:12   ` Longpeng (Mike)
  1 sibling, 1 reply; 5+ messages in thread
From: Herbert Xu @ 2016-12-08  9:04 UTC (permalink / raw)
  To: Longpeng (Mike)
  Cc: jussi.kivilinna, jussi.kivilinna, Gonglei, Zhoujian (jay, Euler),
	Wubin (H), linux-kernel

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@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Question about ctr mode 3des-ede IV len
  2016-12-08  9:04 ` Herbert Xu
@ 2016-12-08  9:12   ` Longpeng (Mike)
  0 siblings, 0 replies; 5+ messages in thread
From: Longpeng (Mike) @ 2016-12-08  9:12 UTC (permalink / raw)
  To: Herbert Xu
  Cc: jussi.kivilinna, jussi.kivilinna, Gonglei, Zhoujian (jay, Euler),
	Wubin (H), linux-kernel



On 2016/12/8 17:04, Herbert Xu wrote:

> 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,


Cool, thank you very much! :)

-- 
Regards,
Longpeng(Mike)

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Question about ctr mode 3des-ede IV len
  2016-12-07 13:15 ` Jussi Kivilinna
@ 2016-12-08 11:29   ` Longpeng (Mike)
  0 siblings, 0 replies; 5+ messages in thread
From: Longpeng (Mike) @ 2016-12-08 11:29 UTC (permalink / raw)
  To: Jussi Kivilinna
  Cc: jussi.kivilinna, herbert, Gonglei, Zhoujian (jay, Euler),
	Wubin (H), linux-kernel

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)

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2016-12-08 11:30 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-12-07 12:43 Question about ctr mode 3des-ede IV len Longpeng (Mike)
2016-12-07 13:15 ` Jussi Kivilinna
2016-12-08 11:29   ` Longpeng (Mike)
2016-12-08  9:04 ` Herbert Xu
2016-12-08  9:12   ` Longpeng (Mike)

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