Re: Multicast support with Linux Ethernet drivers

[Manuel Menal]

Gianluca Guida wrote:
> Hi,

Hi Gianluca,

> There's no a solution still, but it should be quite easy to find one.
> The problem is that the Mach's glue doesn't handle at the moment the
> multicast functionality.
> Your solution should be then to hack the both Mach's device interface
> and it's linux emulation glue to use advanced device functionalities.
> In Mach we don't have an IOCTL interface,  instead we have set_status
> and get_status, which separes reading from writing.
> The problem of nework family devices is that set_device is not even
> implemented in linux glue. This don't let us change the status of the
> device (like MAC address). It's quite easy to implement it though, and
> I think that this is what you might want to do to achieve your goal.
> What you should do is to add to set_status and get_status some kind of
> "NET_MULTICAST" status and set and retrieving it via that interface.
> Note that this will affect the user-level exported interface.

Actually, I've already implemented a (basic) device_set_status for
network devices[0]. Used with this patch for pfinet[1], it makes
SIOCSIFFLAGS change the flags on the Mach device (so that drivers see
they should switch to promisc mode, or receive multicast packets, ...).
It worked last time I checked, but I'm not sure it's enough to handle
multicast packets.

I'll be working on those patches, and BPF as well, during the next week,
so they might change.

Cheers,

[0]: http://perso.hurdfr.org/mmenal/promisc.patch
[1]: http://perso.hurdfr.org/mmenal/patch.pfinet.2

--
Manuel Menal