AF_ALG broken?

Commit Message

Russell King (Oracle) Aug. 9, 2016, 7:27 a.m. UTC

On Tue, Aug 09, 2016 at 03:14:02PM +0800, Herbert Xu wrote:
> On Tue, Aug 09, 2016 at 08:08:59AM +0100, Russell King - ARM Linux wrote:
> > 
> > I thought I gave the commands and link to your example code.  The
> > openssl case is md5, though sha* also gives the same result.  Your
> > example code was sha1 iirc.  I guess none of these would be using
> > HMAC - the openssl cases used to give results compatible with the
> > md5sum/ sha1sum etc userspace commands.
> > 
> > /proc/crypto:
> > 
> > name         : md5
> > driver       : md5-caam
> 
> Right, caam is providing a setkey function for md5, which leads the
> API to think that a key is required.  We should fix it so that setkey
> is only set for the HMAC-variant.

Thanks, that works nicely again, and passes my tests.

8<====
From: Russell King <[e-mail]>
Subject: [PATCH] crypto: caam - fix non-hmac hashes

Since 6de62f15b581 ("crypto: algif_hash - Require setkey before
accept(2)"), the AF_ALG interface requires userspace to provide a key
to any algorithm that has a setkey method.  However, the non-HMAC
algorithms are not keyed, so setting a key is unnecessary.

Fix this by removing the setkey method from the non-keyed hash
algorithms.

Fixes: 6de62f15b581 ("crypto: algif_hash - Require setkey before accept(2)")
Cc: <[e-mail]>
Signed-off-by: Russell King <[e-mail]>
---
 drivers/crypto/caam/caamhash.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Herbert Xu Aug. 9, 2016, 10:35 a.m. UTC | #1

On Tue, Aug 09, 2016 at 08:27:17AM +0100, Russell King - ARM Linux wrote:
>
> From: Russell King <[e-mail]>
> Subject: [PATCH] crypto: caam - fix non-hmac hashes
> 
> Since 6de62f15b581 ("crypto: algif_hash - Require setkey before
> accept(2)"), the AF_ALG interface requires userspace to provide a key
> to any algorithm that has a setkey method.  However, the non-HMAC
> algorithms are not keyed, so setting a key is unnecessary.
> 
> Fix this by removing the setkey method from the non-keyed hash
> algorithms.
> 
> Fixes: 6de62f15b581 ("crypto: algif_hash - Require setkey before accept(2)")
> Cc: <[e-mail]>
> Signed-off-by: Russell King <[e-mail]>

Patch applied.  Thanks.

Patch

diff --git a/drivers/crypto/caam/caamhash.c b/drivers/crypto/caam/caamhash.c
index ea284e3909ef..9d7fc9ec0b7e 100644
--- a/drivers/crypto/caam/caamhash.c
+++ b/drivers/crypto/caam/caamhash.c
@@ -1950,6 +1950,7 @@  caam_hash_alloc(struct caam_hash_template *template,
 			 template->name);
 		snprintf(alg->cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s",
 			 template->driver_name);
+		t_alg->ahash_alg.setkey = NULL;
 	}
 	alg->cra_module = THIS_MODULE;
 	alg->cra_init = caam_hash_cra_init;