Messages in this thread | | | Date | Fri, 14 Aug 2009 11:05:27 +1000 | From | Herbert Xu <> | Subject | Re: [BUGFIX] crypto: Fix ctr(aes) testing by specifying geniv |
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On Fri, Aug 14, 2009 at 09:01:07AM +0800, Huang Ying wrote: > > I see seqiv is used in rfc3686 mode, it means seqiv can not be used on > raw counter mode but can be used for rfc3686?
Yeah, with rfc3686 a portion of the counter is available for counting bytes within each request. This allows a sequential IV to be safely used as each IV is essentially 2^32 blocks apart.
With raw counter mode as soon as you process two blocks in one request the next IV would collide with one that has alreay been used.
Cheers, -- Visit Openswan at http://www.openswan.org/ Email: Herbert Xu ~{PmV>HI~} <herbert@gondor.apana.org.au> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
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