.\" $FreeBSD$ .\" $KAME: gifconfig.8,v 1.6 2000/11/22 11:10:09 itojun Exp $ .\" .\" Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. Neither the name of the project nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .Dd May 17, 1998 .Dt GIFCONFIG 8 .Os .Sh NAME .Nm gifconfig .Nd configure generic IP tunnel .\" .Sh SYNOPSIS .Nm .Ar interface .Op Ar af .Op Ar physsrc physdest .Nm .Ar interface .Ic delete .Nm .Fl a .Sh DESCRIPTION The .Nm utility configures the physical address for the generic IP tunnel inteface, such as "gif0". Argument .Ar physsrc and .Ar physdest are interpreted as the outer source/destination address for encapsulating IPv4/v6 header. Argument .Ar af specifies the address family for .Ar physsrc and .Ar physdest . .Ar af can be .Li inet or .Li inet6 , and will be treated as .Li inet if ommitted. .Pp If a special argument .Ic delete is specified, .Nm just deletes the existing source and destination addresses on .Ar interface . If no outer addresses are specified, this usage has no effect. .Pp The .Nm utility takes the following optional argument: .Bl -tag -width Ds .It Fl a Display information associated with all .Xr gif 4 interfaces. .El .Pp Please note that it is very easy to create infinite routing loop, when you configure tunnel over same address family (e.g. IPv4-over-IPv4). .Pp Each .Xr gif 4 interface is created at runtime using interface cloning. This is most easily done with the .Xr ifconfig 8 .Cm create command or using the .Va gifconfig_ Ns Aq Ar interface variable in .Xr rc.conf 5 . .Sh EXAMPLES If you would like to configure IPv6 over IPv4 (aka IPv6 in IPv4) tunnel between .Li 10.1.1.1 and .Li 10.2.3.4 , you should perform the following command: .Bd -literal -offset # gifconfig gif0 inet 10.1.1.1 10.2.3.4 .Ed .Pp .\" To use the .\" .Li 0.0.0.0 .\" feature to establish a tunnel from host1 to host3 .\" which will encapsulate and carry packets from host2, on host1 do: .\" .Bd -literal -offset .\" # ifconfig gif0 inet host1 127.0.0.2 # assign an address to gif0 .\" # gifconfig gif0 inet host1 0.0.0.0 # assign encapsulation addresses .\" # route add host2 host3 -ifp gif0: # encap host2 packets, send to host3 .\" .Ed .\" .Pp .\" Note: the .\" .Fl ifp .\" option to route does not work as documented in .\" most versions of FreeBSD. .\" .Pp .\" On host3 do: .\" .Bd -literal -offset .\" # ifconfig gif0 inet host3 127.0.0.2 # assign an address to gif0 .\" # gifconfig gif0 inet host3 0.0.0.0 # assign encapsulation addresses .\" .Ed .\" .Pp .\" Now if you ping host2 from host1, the packets should be encapsulated .\" with outer source address = host1 and outer destination address = host3, .\" and delivered to host3. .\" host3 will decapsulate the packet and deliver it normally to host2. .\" .Pp This is also possible to use IPv6 as outer proto, by replacing .Li inet to .Li inet6 , and IPv4 addresses to some appropriate IPv6 addresses in above example. .Sh RETURN VALUES The command exits with exit status of 1 on errors, 0 on success. .Sh SEE ALSO .Xr gif 4 , .Xr ifconfig 8 .Sh HISTORY The .Nm utility first appeared in WIDE Hydrangea IPv6 protocol stack kit. .Pp IPv6 and IPsec support based on the KAME Project (http://www.kame.net/) stack was initially integrated into .Fx 4.0