Re: [PATCH] crypto: aesni: add setkey for driver-gcm-aes-aesni

[Stephan Mueller <smueller@chronox.de>]

Am Dienstag, 20. Januar 2015, 14:17:04 schrieb Herbert Xu:

Hi Herbert,

>On Sun, Jan 18, 2015 at 11:56:03PM +0100, Stephan Mueller wrote:
>> The cipher registered as __driver-gcm-aes-aesni is never intended
>> to be used directly by any caller. Instead it is a service mechanism
>> to rfc4106-gcm-aesni.
>> 
>> The kernel crypto API unconditionally calls the registered setkey
>> function. In case a caller erroneously uses __driver-gcm-aes-aesni a
>> call to crypto_aead_setkey will cause a NULL pointer dereference
>> without this patch.
>> 
>> CC: Tadeusz Struk <tadeusz.struk@intel.com>
>> Signed-off-by: Stephan Mueller <smueller@chronox.de>
>
>Rather than adding a bogus setkey function, please fix this mess
>properly by moving the top-level setkey function into the __driver
>one where it should be.  Compare with how we handle it in the
>ablk_helper which is pretty much the same thing.

That is a good suggestion. And the modification is quite limited as the 
existing rfc4106_set_key could be used for the __driver with only slight 
modifications.

In that case, however, we should apply the same to rfc4106_set_authsize.

This in turn would then turn the __driver implementation into a full GCM 
implementation. That would mean that we should rename it from __driver 
into gcm(aes) / gcm-aesni. 
>
>Thanks,


Ciao
Stephan