2011-04-19 19:34:01

by Jan Glauber

[permalink] [raw]
Subject: [PATCH 7/8] tcrypt: disable 384 bit key XTS test

From: Jan Glauber <[email protected]>

XTS mode is only defined for 256 and 512 bit key lengths. s390 only
implements these two modes and running the test with a 384 bit key
will stop the speed test with an error. Remove the superfluous key
lenght.

Signed-off-by: Jan Glauber <[email protected]>
---
crypto/tcrypt.c | 4 ++--
crypto/tcrypt.h | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)

--- a/crypto/tcrypt.c
+++ b/crypto/tcrypt.c
@@ -1006,9 +1006,9 @@ static int do_test(int m)
test_cipher_speed("lrw(aes)", DECRYPT, sec, NULL, 0,
speed_template_32_40_48);
test_cipher_speed("xts(aes)", ENCRYPT, sec, NULL, 0,
- speed_template_32_48_64);
+ speed_template_32_64);
test_cipher_speed("xts(aes)", DECRYPT, sec, NULL, 0,
- speed_template_32_48_64);
+ speed_template_32_64);
break;

case 201:
--- a/crypto/tcrypt.h
+++ b/crypto/tcrypt.h
@@ -51,7 +51,7 @@ static u8 speed_template_8_32[] = {8, 32
static u8 speed_template_16_32[] = {16, 32, 0};
static u8 speed_template_16_24_32[] = {16, 24, 32, 0};
static u8 speed_template_32_40_48[] = {32, 40, 48, 0};
-static u8 speed_template_32_48_64[] = {32, 48, 64, 0};
+static u8 speed_template_32_64[] = {32, 64, 0};

/*
* Digest speed tests

--


2011-04-20 00:33:55

by Herbert Xu

[permalink] [raw]
Subject: Re: [PATCH 7/8] tcrypt: disable 384 bit key XTS test

On Tue, Apr 19, 2011 at 09:29:20PM +0200, [email protected] wrote:
> From: Jan Glauber <[email protected]>
>
> XTS mode is only defined for 256 and 512 bit key lengths. s390 only
> implements these two modes and running the test with a 384 bit key
> will stop the speed test with an error. Remove the superfluous key
> lenght.
>
> Signed-off-by: Jan Glauber <[email protected]>

That's a limitation specific to your hardware. As the existing xts
currently supports 384-bit keys, we can't remove it for compatibility
reasons. So please add it as a fallback to your implementation.

Thanks,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt

2011-04-20 15:19:57

by Jan Glauber

[permalink] [raw]
Subject: Re: [PATCH 7/8] tcrypt: disable 384 bit key XTS test

On Wed, 2011-04-20 at 08:33 +0800, Herbert Xu wrote:
> On Tue, Apr 19, 2011 at 09:29:20PM +0200, [email protected] wrote:
> > From: Jan Glauber <[email protected]>
> >
> > XTS mode is only defined for 256 and 512 bit key lengths. s390 only
> > implements these two modes and running the test with a 384 bit key
> > will stop the speed test with an error. Remove the superfluous key
> > lenght.
> >
> > Signed-off-by: Jan Glauber <[email protected]>
>
> That's a limitation specific to your hardware. As the existing xts
> currently supports 384-bit keys, we can't remove it for compatibility
> reasons. So please add it as a fallback to your implementation.

I see, will try to hack something together.

Bad thing is, we don't even have a test vector for the 384 bit key length
and the standards don't provide one.

Should I resend when I'm finished or would you like to drop this patch
from the series?

Cheers,
Jan

2011-04-20 15:35:08

by Herbert Xu

[permalink] [raw]
Subject: Re: [PATCH 7/8] tcrypt: disable 384 bit key XTS test

On Wed, Apr 20, 2011 at 05:19:52PM +0200, Jan Glauber wrote:
>
> Should I resend when I'm finished or would you like to drop this patch
> from the series?

I'll go through the rest of your series and apply them. So just
treat this as an individual patch.

Thanks,
--
Email: Herbert Xu <[email protected]>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt