[PATCH 0/4] KEYS: trusted: Introduce support for NXP CAAM-based trusted keys

[Ahmad Fatoum]

Hello David,

On 10.08.21 13:28, David Gstir wrote:
> Hi Ahmad,
> 
>> On 09.08.2021, at 12:16, Ahmad Fatoum <a.fatoum at pengutronix.de> wrote:
> 
> [...]
> 
>> If it interests you, I described[2] my CAAM+ubifs+fscrypt use case in the
>> discussion thread on my fscrypt-trusted-keys v1. Jan, a colleague of mine, held a
>> talk[3] on the different solutions for authenticated and encrypted storage, which
>> you may want to check out.
>>
>> I'd really appreciate feedback here on the the CAAM parts of this series, so this can
>> eventually go mainline.
> 
> Since you mention the fscrypt trusted-keys use case:
> 
> I noticed that the key length for trusted-keys is limited to
> 256 - 1024bit keys. fscrypt does however also support keys
> with e.g. 128bit keys (AES-128-CBC-ESSIV, AES-128-CTS-CBC).
> AFAIK, CAAM and TEE key blobs would also support key lengths outside the 256 - 1024bit range.
> 
> Wouldn’t it make sense to align the supported key lengths?
> I.e. extend the range of supported key lengths for trusted keys.
> Or is there a specific reason why key lengths below 256bit are
> not supported by trusted-keys?

No idea. I would suggest staying clear about arguing in its favor though
until CAAM and DCP are merged. My parallel fscrypt endeavors seem to have
only diverted maintainer attention. ;-)

Cheers,
Ahmad

> 
> Cheers,
> David
> 
> 
> 


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