From owner-freebsd-hackers Wed Apr 17 12:05:11 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.3/8.7.3) id MAA28130 for hackers-outgoing; Wed, 17 Apr 1996 12:05:11 -0700 (PDT) Received: from palmer.demon.co.uk (palmer.demon.co.uk [158.152.50.150]) by freefall.freebsd.org (8.7.3/8.7.3) with ESMTP id MAA28116 for ; Wed, 17 Apr 1996 12:05:03 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by palmer.demon.co.uk (sendmail/PALMER-1) with SMTP id UAA02480 ; Wed, 17 Apr 1996 20:03:49 +0100 (BST) To: dirk@methan.chemie.fu-berlin.de (Dirk Froemberg) cc: hackers@FreeBSD.ORG, xadmin@methan.chemie.fu-berlin.de, alf@bolzen.in-berlin.de From: "Gary Palmer" Subject: Re: ip-in-ip tunnel In-reply-to: Your message of "Wed, 17 Apr 1996 13:12:46 +0200." Date: Wed, 17 Apr 1996 20:03:49 +0100 Message-ID: <2478.829767829@palmer.demon.co.uk> Sender: owner-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk Dirk Froemberg wrote in message ID : > Hello! > > We need to set up a ip-in-ip (protocol number 4) tunnel with FreeBSD > (i. e. tunnel entry should be on a FreeBSD machine). > > Unfortunaly there seems to be no easy way of doing so. Heh. A always, depends on your definition of ``easy'' :-) I suggest looking at the sources for the IIJPPP program (/usr/src/usr.sbin/ppp) which uses the `tun' device. This will allow you to have packets delivered to a user-level program from the kernel. The kerenl just treats the `tun' interface like a normal network I/F, and you can do what you like with the packets once they are delivered to your program. You can feed packets back into the kernel too, of course, which is how user-mode ppp works... (and how this e-mail is being sent :-) ) It should be ``relatively'' easy to modify /usr/sbin/ppp to deliver packets over a TCP/IP link rather than a serial port. Gary