Messages in this thread | | | Date | Tue, 11 Jul 2006 16:01:46 +1000 | Subject | Re: [ACRYPTO] new release of asynchronous crrypto layer. | From | Herbert Xu <> |
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Hi Evgeniy:
On Tue, Jul 11, 2006 at 09:31:57AM +0400, Evgeniy Polyakov wrote: > > > I noticed a bug in the ESP IV processing. When you do ESP asynchronously, > > you can no longer use the last block of the previous packet as the IV of > > the next. This is because the next packet may have started processing > > before the last packet has even been finalised. > > I cought that bug too, so IV being used is always copied into old_iv variable, > so integrity is stated.
My point is that it is possible for two packets to use the same IV under this scheme, which defeats the purpose of IVs.
> > A simple solution is to generate a random IV. > > Yes, it could be done too. > But actually neither random IV, nor IV created from encrypted previous packet, > nor IV created from unencrypted previous packet are forbidden by spec. > Initial implementation used constant IV there at all.
True. However, using the same IV more than once is definitely not a good idea.
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 - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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