Re: [PATCH v5 5/5] selftests/bpf: Add test for bpf_verify_pkcs7_signature() helper

[Alexei Starovoitov]

On Wed, Jun 22, 2022 at 12:06 AM Roberto Sassu <roberto.sassu@xxxxxxxxxx> wrote:
>
> > From: Alexei Starovoitov [mailto:alexei.starovoitov@xxxxxxxxx]
> > Sent: Wednesday, June 22, 2022 12:32 AM
> > On Tue, Jun 21, 2022 at 06:37:57PM +0200, Roberto Sassu wrote:
> > > +   if (child_pid == 0) {
> > > +           snprintf(path, sizeof(path), "%s/signing_key.pem", tmp_dir);
> > > +
> > > +           return execlp("./sign-file", "./sign-file", "-d", "sha256",
> > > +                         path, path, data_template, NULL);
> >
> > Did you miss my earlier reply requesting not to do this module_signature append
> > and use signature directly?
>
> I didn't miss. sign-file is producing the raw PKCS#7 signature here (-d).
>
> I'm doing something slightly different, to test the keyring ID part.
> I'm retrieving an existing kernel module (actually this does not work
> in the CI), parsing it to extract the raw signature, and passing it to the
> eBPF program for verification.

We don't have signed modules in CI.
When you make changes like this you have to explain that in the commit log.

> Since the kernel module is signed with a key in the built-in keyring,
> passing 1 or 0 as ID should work.
>
> Roberto
>
> (sorry, I have to keep the email signature by German law)

I don't believe that's the case since plenty of people
work from Germany and regularly contribute patches without
such banners.

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