diff mbox

crypto: Add a flag allowing the self-tests to be disabled at runtime.

Message ID 1461924463-1678-2-git-send-email-rjones@redhat.com (mailing list archive)
State Superseded
Delegated to: Herbert Xu
Headers show

Commit Message

Richard W.M. Jones April 29, 2016, 10:07 a.m. UTC
Running self-tests for a short-lived KVM VM takes 28ms on my laptop.
This commit adds a flag 'cryptomgr.notests' which allows them to be
disabled.

Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
---
 Documentation/kernel-parameters.txt | 3 +++
 crypto/testmgr.c                    | 9 +++++++++
 2 files changed, 12 insertions(+)

Comments

Stephan Mueller April 29, 2016, 10:59 a.m. UTC | #1
Am Freitag, 29. April 2016, 11:07:43 schrieb Richard W.M. Jones:

Hi Richard,

> Running self-tests for a short-lived KVM VM takes 28ms on my laptop.
> This commit adds a flag 'cryptomgr.notests' which allows them to be
> disabled.
> 
> Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
> ---
>  Documentation/kernel-parameters.txt | 3 +++
>  crypto/testmgr.c                    | 9 +++++++++
>  2 files changed, 12 insertions(+)
> 
> diff --git a/Documentation/kernel-parameters.txt
> b/Documentation/kernel-parameters.txt index 0b3de80..d4d5fb7 100644
> --- a/Documentation/kernel-parameters.txt
> +++ b/Documentation/kernel-parameters.txt
> @@ -826,6 +826,9 @@ bytes respectively. Such letter suffixes can also be
> entirely omitted. It will be ignored when crashkernel=X,high is not used
>  			or memory reserved is below 4G.
> 
> +	cryptomgr.notests
> +                        [KNL] Disable crypto self-tests
> +
>  	cs89x0_dma=	[HW,NET]
>  			Format: <dma>
> 
> diff --git a/crypto/testmgr.c b/crypto/testmgr.c
> index b86883a..dc613f2 100644
> --- a/crypto/testmgr.c
> +++ b/crypto/testmgr.c
> @@ -35,6 +35,10 @@
> 
>  #include "internal.h"
> 
> +static bool notests;
> +module_param(notests, bool, 0644);
> +MODULE_PARM_DESC(notests, "disable crypto self-tests");
> +
>  #ifdef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
> 
>  /* a perfect nop */
> @@ -3868,6 +3872,11 @@ int alg_test(const char *driver, const char *alg, u32
> type, u32 mask) int j;
>  	int rc;
> 
> +	if (notests) {

What about if (!fips_enabled && notests) ?

I am not sure whether the kernel should prevent mistakes in user space. A 
mistake would be when setting fips=1 and notests=1 as the FIPS mode mandates 
the self tests.

> +		pr_info("alg: self-tests disabled\n");
> +		return 0;
> +	}
> +
>  	alg_test_descs_check_order();
> 
>  	if ((type & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_CIPHER) {


Ciao
Stephan
Richard W.M. Jones April 29, 2016, 11:04 a.m. UTC | #2
On Fri, Apr 29, 2016 at 12:59:57PM +0200, Stephan Mueller wrote:
> Am Freitag, 29. April 2016, 11:07:43 schrieb Richard W.M. Jones:
> 
> Hi Richard,
[...]
> > +	if (notests) {
> 
> What about if (!fips_enabled && notests) ?
>
> I am not sure whether the kernel should prevent mistakes in user space. A 
> mistake would be when setting fips=1 and notests=1 as the FIPS mode mandates 
> the self tests.

(Sorry, I just posted v2 before I saw this message.)  I saw the FIPS
stuff and thought about that.  Should we prevent mistakes like that?
I really don't know.

Rich.

> > +		pr_info("alg: self-tests disabled\n");
> > +		return 0;
> > +	}
> > +
> >  	alg_test_descs_check_order();
> > 
> >  	if ((type & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_CIPHER) {
> 
> 
> Ciao
> Stephan
> -- 
> | Nimm das Recht weg -                                             |
> |  was ist dann der Staat noch anderes als eine große Räuberbande? |
diff mbox

Patch

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 0b3de80..d4d5fb7 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -826,6 +826,9 @@  bytes respectively. Such letter suffixes can also be entirely omitted.
 			It will be ignored when crashkernel=X,high is not used
 			or memory reserved is below 4G.
 
+	cryptomgr.notests
+                        [KNL] Disable crypto self-tests
+
 	cs89x0_dma=	[HW,NET]
 			Format: <dma>
 
diff --git a/crypto/testmgr.c b/crypto/testmgr.c
index b86883a..dc613f2 100644
--- a/crypto/testmgr.c
+++ b/crypto/testmgr.c
@@ -35,6 +35,10 @@ 
 
 #include "internal.h"
 
+static bool notests;
+module_param(notests, bool, 0644);
+MODULE_PARM_DESC(notests, "disable crypto self-tests");
+
 #ifdef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
 
 /* a perfect nop */
@@ -3868,6 +3872,11 @@  int alg_test(const char *driver, const char *alg, u32 type, u32 mask)
 	int j;
 	int rc;
 
+	if (notests) {
+		pr_info("alg: self-tests disabled\n");
+		return 0;
+	}
+
 	alg_test_descs_check_order();
 
 	if ((type & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_CIPHER) {