Re: [RFC PATCH net-next v3 1/5] gtp: Allow to create GTP device without FDs

[Harald Welte <laforge@osmocom.org>]

Hi Wojciech,

On Tue, Feb 08, 2022 at 01:30:32PM +0000, Drewek, Wojciech wrote:

> For now we don't have such tree. I will see what we can do.

I would appreciate it, so we can get this tested before it hits net-next.

> > I'm wondering if we should make this more explicit, i.e. rather than
> > implicitly creating the kernel socket automagically, make this mode
> > explicit upon request by some netlink attribute.
>
> I agree, it would look cleaner.

Excellent.

> > > Sockets are created with the
> > > commonly known UDP ports used for GTP protocol (GTP0_PORT and
> > > GTP1U_PORT).
> > 
> > I'm wondering if there are use cases that need to operate on
> > non-standard ports.  The current module can be used that way (as the
> > socket is created in user space). If the "kernel socket mode" was
> > requested explicitly via netlink attribute, one could just as well
> > pass along the port number[s] this way.
>
> Yes, it is possible to create socket with any port number using FD approach,
> but gtp module still assumes that ports are 2152 and 3386 at least in tx path
> (see gtp_push_header).  Implementing this shouldn't be hard but is it crucial?

Not crucial.

-- 
- Harald Welte <laforge@osmocom.org>            http://laforge.gnumonks.org/
============================================================================
"Privacy in residential applications is a desirable marketing option."
                                                  (ETSI EN 300 175-7 Ch. A6)