Re: [RFC PATCH 4/5] crypto: Adds user space interface for ALG_SET_KEY_TYPE

From: Stephan Mueller
Date: Fri May 24 2019 - 03:23:30 EST


Am Mittwoch, 8. Mai 2019, 11:31:08 CEST schrieb Kalyani Akula:

Hi Kalyani,

> Hi Stephan,
>
> Keyrings is in-kernel key-management and retention facility. User can use it
> to manage keys used for applications.
>
> Xilinx cryptographic hardware has a mechanism to store keys in its internal
> hardware and do not have mechanism to read it back due to security reasons.
> It stores key internally in different forms like simple key, key encrypted
> with unique hardware DNA, key encrypted with hardware family key, key
> stored in eFUSEs/BBRAM etc.
> Based on security level expected, user can select one of the key for AES
> operation. Since AES hardware internally has access to these keys, user do
> not require to provide key to hardware, but need to tell which internal
> hardware key user application like to use for AES operation.
>
> Basic need is to pass information to AES hardware about which internal
> hardware key to be used for AES operation.
>
> I agree that from general use case perspective we are not selecting key type
> but selecting internal hardware keys provided by user. How about providing
> option to select custom hardware keys provided by hardware
> (AES_SEL_HW_KEY)?

I am not intimately familiary with the keyring facility. Thus, let us ask the
experts at the keyring mailing list :-)

>
> Thanks
> kalyani
>
> > -----Original Message-----
> > From: Stephan Mueller <smueller@xxxxxxxxxx>
> > Sent: Thursday, April 25, 2019 12:01 AM
> > To: Kalyani Akula <kalyania@xxxxxxxxxx>
> > Cc: herbert@xxxxxxxxxxxxxxxxxxx; davem@xxxxxxxxxxxxx; linux-
> > crypto@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> > Subject: Re: [RFC PATCH 4/5] crypto: Adds user space interface for
> > ALG_SET_KEY_TYPE
> >
> > Am Montag, 22. April 2019, 11:17:55 CEST schrieb Kalyani Akula:
> >
> > Hi Kalyani,
> >
> > > > Besides, seem to be more a key handling issue. Wouldn't it make
> > > > sense to rather have such issue solved with key rings than in the
> > > > kernel crypto API?
> > >
> > > [kalyani] Can you please elaborate on this further ?
> >
> > The kernel has a keyring support in security/keys which has a user space
> > interface with keyutils. That interface is commonly used for any sort of
> > key manipulation.
> >
> > Ciao
> > Stephan



Ciao
Stephan