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

Tim Harvey tharvey at gateworks.com
Tue Aug 24 15:23:32 UTC 2021


On Tue, Aug 24, 2021 at 12:33 AM Ahmad Fatoum <a.fatoum at pengutronix.de> wrote:
>
> On 23.08.21 19:50, Tim Harvey wrote:
> > On Mon, Aug 23, 2021 at 6:29 AM Ahmad Fatoum <a.fatoum at pengutronix.de> wrote:
> >> On 20.08.21 23:19, Tim Harvey wrote:
> >>> On Fri, Aug 20, 2021 at 1:36 PM Ahmad Fatoum <a.fatoum at pengutronix.de> wrote:
> >>>> On 20.08.21 22:20, Tim Harvey wrote:
> >>> It works for a user keyring but not a session keyring... does that
> >>> explain anything?
> >>> # keyctl add trusted mykey 'new 32' @u
> >>> 941210782
> >>> # keyctl print 941210782
> >>> 83b7845cb45216496aead9ee2c6a406f587d64aad47bddc539d8947a247e618798d9306b36398b5dc2722a4c3f220a3a763ee175f6bd64758fdd49ca4db597e8ce328121b60edbba9b8d8d55056be896
> >>> # keyctl add trusted mykey 'new 32' @s
> >>> 310571960
> >>> # keyctl print 310571960
> >>> keyctl_read_alloc: Unknown error 126
> >>
> >> Both sequences work for me.
> >>
> >> My getty is started by systemd. I think systemd allocates a new session
> >> keyring for the getty that's inherited by the shell and the commands I run
> >> it in. If you don't do that, each command will get its own session key.
> >>
> >>> Sorry, I'm still trying to wrap my head around the differences in
> >>> keyrings and trusted vs user keys.
> >>
> >> No problem. HTH.
> >
> > Ahmad,
> >
> > Ok that explains it - my testing is using a very basic buildroot
> > ramdisk rootfs. If I do a 'keyctl new_session' first I can use the
> > system keyring fine as well.
>
> Great. Does this mean I can get your Tested-by: ? :)
>

Absolutely,

For the series:

I tested this series on top of v5.14.rc-7 on a Gateworks
imx8mm-venice-gw73xx board with kernel param trusted.source=caam and
keyutils-1.6:
# keyctl new_session
22544757
# keyctl add trusted mykey 'new 32' @s
160701809
# keyctl print 160701809
990e03aa4515aee420eede17e26a58d0c5568c8bd2c9c2ee2f22a0583181d20d4f65cf9cb1f944a3cc92c0e3184a44a29a7e511f0a55a6af11a70ac2b2924514002475e73ae09820042896b9ee00a5ec

Tested-By: Tim Harvey <tharvey at gateworks.com>

One more question: I've got a user that wants to blob/deblob generic
data. They can use the caam_encap_blob/caam_decap_blob functions in
kernel code but could you give me a suggestion for how they could use
this in:
a) userspace code (using the keyctl syscall I assume)
b) userspace cmdline (via keyutils I assume)

Many thanks,

Tim



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