Re: [PATCH v2 6/6] KEYS: trusted: Introduce support for NXP CAAM-based trusted keys

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hello Richard,

On 01.07.21 22:42, Richard Weinberger wrote:
> Ahmad,
> 
> ----- Ursprüngliche Mail -----
>> Von: "Ahmad Fatoum" <a.fatoum@pengutronix.de>
>> +static struct caam_blob_priv *blobifier;
>> +
>> +#define KEYMOD "kernel:trusted"
> 
> I'm still think that hard coding the key modifier is not wise.
> As I said[0], there are folks out there that want to provide their own modifier,
> so it is not only about being binary compatible with other CAAM blob patches in the wild.

I don't think the characterization as a salt is accurate. AFAIU it's more
of a namespace, so blobs being loaded are "type-checked" against the modifier.

> I'll happily implement that feature after your patches got merged but IMHO we should first agree on an interface.
> How about allowing another optional parameter to Opt_new and Opt_load

Sound good to me. pcrlock for TPM trusted keys has the same interface.

I'd prefer the new option to accept strings, not hex though.


> and having a key modifier per struct trusted_key_payload instance?

Ye, possibly a void *backend_data, which other trust sources could leverage
as well. But that should be separate discussion.


Cheers,
Ahmad

> 
> Thanks,
> //richard
> 
> [0]
> https://patchwork.kernel.org/project/linux-crypto/patch/319e558e1bd19b80ad6447c167a2c3942bdafea2.1615914058.git-series.a.fatoum@pengutronix.de/#24085397
> 
> 

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