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Date:   Mon, 11 Oct 2021 22:06:17 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Paul Moore <paul@paul-moore.com>
Cc:     Ondrej Mosnacek <omosnace@redhat.com>,
        Florian Westphal <fw@strlen.de>,
        SElinux list <selinux@vger.kernel.org>,
        Stephen Smalley <stephen.smalley.work@gmail.com>,
        Eric Paris <eparis@parisplace.org>,
        Linux kernel mailing list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2 selinux] selinux: remove unneeded ipv6 hook wrappers
Message-ID: <20211011200617.GA2942@breakpoint.cc>
References: <20211011142416.26798-1-fw@strlen.de>
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Paul Moore <paul@paul-moore.com> wrote:
> On Mon, Oct 11, 2021 at 2:21 PM Ondrej Mosnacek <omosnace@redhat.com> wrote:
> > On Mon, Oct 11, 2021 at 7:10 PM Paul Moore <paul@paul-moore.com> wrote:
> > > On Mon, Oct 11, 2021 at 10:25 AM Florian Westphal <fw@strlen.de> wrote:
> > > > Netfilter places the protocol number the hook function is getting called
> > > > from in state->pf, so we can use that instead of an extra wrapper.
> > > >
> > > > Signed-off-by: Florian Westphal <fw@strlen.de>
> > > > ---
> > > >  v2: add back '#endif /* CONFIG_NETFILTER */' erronously axed in v1.
> > > >  Applies to 'next' branch of
> > > >  https://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux.git/
> > > >
> > > >  security/selinux/hooks.c | 52 ++++++++++------------------------------
> > > >  1 file changed, 12 insertions(+), 40 deletions(-)
> > >
> > > ...
> > >
> > > > diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> > > > index e7ebd45ca345..831b857d5dd7 100644
> > > > --- a/security/selinux/hooks.c
> > > > +++ b/security/selinux/hooks.c
> > > > @@ -7470,38 +7442,38 @@ DEFINE_LSM(selinux) = {
> > > >
> > > >  static const struct nf_hook_ops selinux_nf_ops[] = {
> > > >         {
> > > > -               .hook =         selinux_ipv4_postroute,
> > > > +               .hook =         selinux_hook_postroute,
> > > >                 .pf =           NFPROTO_IPV4,
> > > >                 .hooknum =      NF_INET_POST_ROUTING,
> > > >                 .priority =     NF_IP_PRI_SELINUX_LAST,
> > > >         },
> > >
> > > Thanks for the patch Florian, although the name "selinux_hook_*" seems
> > > a bit ambiguous to me, after all we have a little more than 200
> > > "hooks" in the SELinux LSM implementation.  Would you be okay with
> > > calling the netfilter hook functions "selinux_nf_*" or something
> > > similar?

Absolutely.

> > > If you don't have time I can do the rename during the merge
> > > assuming we can all agree on a name.

I'll submit a v3.

> > Since selinux_ip_forward() and selinux_ip_postroute() are used only in
> > the hook functions, how about changing their signature and using them
> > as hooks directly? That would solve the naming and also remove a few
> > extra lines of boilerplate.
> 
> No argument against that from me, although you should be able to do
> the same for selinux_ip_output() as well unless I missed a caller.

I'll have a look, thanks for the pointers.