[PATCH 0/3] Add LSM/SELinux support for GPRS Tunneling Protocol (GTP)

[Richard Haines]

On Wed, 2020-09-30 at 12:17 +0200, Pablo Neira Ayuso wrote:
> On Wed, Sep 30, 2020 at 10:49:31AM +0100, Richard Haines wrote:
> > These patches came about after looking at 5G open source in
> > particular
> > the updated 5G GTP driver at [1]. As this driver is still under
> > development, added the LSM/SELinux hooks to the current stable GTP
> > version in kernel selinux-next [2]. Similar hooks have also been
> > implemented in [1] as it uses the same base code as the current 3G
> > version (except that it handles different packet types).
> 
> Yes, [1] looks like it is based on the existing 3G driver in the
> Linux
> tree.

After a few fixes to [1], I now have the gtp5g version driver running
on 5.9 with security hooks and passing their couple of tests.

> 
> > To test the 3G GTP driver there is an RFC patch for the selinux-
> > testsuite
> > at [3].
> > 
> > To enable the selinux-testsuite GTP tests, the libgtpnl [4] library
> > and
> > tools needed to be modified to:
> > Return ERRNO on error to detect EACCES, Add gtp_match_tunnel
> > function,
> > Allow gtp-link to specify port numbers for multiple instances to
> > run in the same namespace.
> > 
> > A patch for libgtpnl is supplied in the selinux-testsuite patch as
> > well
> > as setup/test instructions (libgtpnl is not packaged by Fedora)
> > 
> > These patches were tested on Fedora 32 with kernel [2] using the
> > 'targeted' policy. Also ran the Linux Kernel GTP-U basic tests [5].
> 
> I don't remember to have seen anything similar in the existing tunnel
> net_devices.
> 
> Why do you need this?

I don't actually have a use for this, I only did it out of idle
curiosity. If it is useful to the community then okay. Given the
attemped move to Open 5G I thought adding MAC support might be useful
somewhere along the line.

> 
> > [1] https://github.com/PrinzOwO/gtp5g