Re: [RFC v3 27/27] rspdm: Multicast received signatures via netlink

[Lukas Wunner <lukas@wunner.de>]

On Wed, Feb 11, 2026 at 01:29:34PM +1000, alistair23@gmail.com wrote:
> This is based on Lukas's patch from [1]. This exposes all of the SPDM
> information to userspace via netlink. This includes the certificate
> chain and communication transcript.
> 
> 1: https://github.com/l1k/linux/commit/fe90b5700ee9bc595a21c030192eac4060eaeae1

Just a heads-up, the above-linked commit is from Dec 11, but I spent
the calm days around Christmas and New Year testing and improving the
SPDM netlink code.  I ended up squashing quite a few bugs and refactoring
things for clarity.  Latest version is on my development branch:

https://github.com/l1k/linux/commits/doe

The branch contains a separate commit introducing a nla_put_blob()
helper to add a zero-copy blob attribute to an skb.  And the SPDM
netlink code uses that helper instead of open coding its contents.

The SPDM netlink code can be tested with:

tools/net/ynl/pyynl/cli.py \
     --spec Documentation/netlink/specs/spdm.yaml \
     --subscribe sig  --sleep 10

Just reauthenticate the device and the signature with ancillary
data gets dumped via netlink.

The commit message and kernel-doc of the SPDM netlink commit is
still a WIP because right after the calm of the holidays I got
swamped (again) with AER work that my employeer prioritizes.
But the code is now well-tested.

Thanks,

Lukas