Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 6 Oct 1998 15:03:59 PDT
From:      Bill Fenner <fenner@parc.xerox.com>
To:        "David E. Cross" <crossd@null.cs.rpi.edu>
Cc:        freebsd-hackers@FreeBSD.ORG
Subject:   Re: GRE support in FreeBSD? 
Message-ID:  <98Oct6.150408pdt.177476@crevenia.parc.xerox.com>
In-Reply-To: Your message of "Tue, 06 Oct 98 12:34:40 PDT." <Pine.SGI.4.04.9810061533400.3218-100000@null.cs.rpi.edu> 

next in thread | previous in thread | raw e-mail | index | archive | help
It wouldn't take much to add to the kernel.  Look at ip_mroute.c's
ipip_input() to see how it decapsulates ip proto 4, and at encap_send()
to see how it encapsulates.  You'd have to create real interfaces,
which the multicast code doesn't do, but it's really fairly straightforward.

I know that NetBSD is working on general IP proto 4 tunnels in the
kernel and they have an API for setting the tunnel's IP source and
destination.  I don't know if they're doing GRE also, but perhaps you
could look at what they're doing and see if it'd be applicable.

I've thought for a while that there should be a generalized tunneling
mechanism (e.g. hand the kernel an IP header to prepend with an ioctl
and a bpf program to do decapsulation but otherwise live in the
standard demux mechanism) but doing that right is too much more work
than having N different tunneling mechanisms...

  Bill

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-hackers" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?98Oct6.150408pdt.177476>