From: Herbert Xu <herbert@gondor.apana.org.au>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: Eric Biggers <ebiggers@kernel.org>,
Stephan Mueller <smueller@chronox.de>,
Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [RFC/RFT PATCH 0/2] crypto: add CTS output IVs for arm64 and testmgr
Date: Fri, 29 May 2020 18:05:08 +1000 [thread overview]
Message-ID: <20200529080508.GA2880@gondor.apana.org.au> (raw)
In-Reply-To: <CAMj1kXGkvLP1YnDimdLOM6xMXSQKXPKCEBGRCGBRsWKAQR5Stg@mail.gmail.com>
On Thu, May 28, 2020 at 10:33:25AM +0200, Ard Biesheuvel wrote:
>
> The reason we return output IVs for CBC is because our generic
> implementation of CTS can wrap any CBC implementation, and relies on
> this output IV rather than grabbing it from the ciphertext directly
> (which may be tricky and is best left up to the CBC code)
No that's not the main reason. The main user of chaining is
algif_skcipher.
> So if you are saying that we should never split up algif_skcipher
> requests into multiple calls into the underlying skcipher, then I
> agree with you. Even if the generic CTS seems to work more or less as
> expected by, e.g., the NIST validation tool, this is unspecified
> behavior, and definitely broken in various other places.
I was merely suggesting that requests to CTS/XTS shouldn't be
split up. Doing it for others would be a serious regression.
However, having looked at this it would seem that the effort
in marking CTS/XTS is not that different to just adding support
to hold the last two blocks of data so that CTS/XTS can support
chaining.
I'll work on this.
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
_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2020-05-29 8:05 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-05-19 19:02 [RFC/RFT PATCH 0/2] crypto: add CTS output IVs for arm64 and testmgr Ard Biesheuvel
2020-05-19 19:02 ` [RFC/RFT PATCH 1/2] crypto: arm64/aes - align output IV with generic CBC-CTS driver Ard Biesheuvel
2020-05-19 19:02 ` [RFC/RFT PATCH 2/2] crypto: testmgr - add output IVs for AES-CBC with ciphertext stealing Ard Biesheuvel
2020-05-19 19:04 ` [RFC/RFT PATCH 0/2] crypto: add CTS output IVs for arm64 and testmgr Ard Biesheuvel
2020-05-20 6:03 ` Stephan Mueller
2020-05-20 6:40 ` Ard Biesheuvel
2020-05-20 6:47 ` Stephan Mueller
2020-05-20 6:54 ` Ard Biesheuvel
2020-05-20 7:01 ` Stephan Mueller
2020-05-20 7:09 ` Ard Biesheuvel
2020-05-21 13:01 ` Gilad Ben-Yossef
2020-05-21 13:23 ` Ard Biesheuvel
2020-05-23 18:52 ` Stephan Müller
2020-05-23 22:40 ` Ard Biesheuvel
2020-05-28 7:33 ` Herbert Xu
2020-05-28 8:33 ` Ard Biesheuvel
2020-05-29 8:05 ` Herbert Xu [this message]
2020-05-29 8:20 ` Ard Biesheuvel
2020-05-29 11:51 ` Herbert Xu
2020-05-29 12:00 ` Ard Biesheuvel
2020-05-29 12:02 ` Herbert Xu
2020-05-29 13:10 ` Ard Biesheuvel
2020-05-29 13:19 ` Herbert Xu
2020-05-29 13:41 ` Ard Biesheuvel
2020-05-29 13:42 ` Herbert Xu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200529080508.GA2880@gondor.apana.org.au \
--to=herbert@gondor.apana.org.au \
--cc=ardb@kernel.org \
--cc=ebiggers@kernel.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-crypto@vger.kernel.org \
--cc=smueller@chronox.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).