|GIF(4)||Device Drivers Manual||GIF(4)|
gifinterface is a generic tunnelling pseudo-device. It can tunnel IPv4, IPv6, and MPLS over IPv4 and IPv6, with behavior mainly based on RFC 4213 IPv6-over-IPv4.
gif interface must be configured with
the addresses used for the outer header. This can be done by using
tunnel command (which uses the
The addresses of the inner header must be configured by using
ifconfig(8) in the normal way. The
routing table can be used to direct packets toward the
T. Worster, Y. Rekhter, and E. Rosen, Encapsulating MPLS in IP or Generic Routing Encapsulation (GRE), RFC 4023, March 2005.
gifdevice first appeared in WIDE hydrangea IPv6 kit.
gifmay not interoperate with peers which are based on different specifications, and are picky about outer header fields. For example, you cannot usually use
gifto talk with IPsec devices that use IPsec tunnel mode.
The current code does not check if the ingress address (outer
source address) configured to
gif makes sense. Make
sure to configure an address which belongs to your node. Otherwise, your
node will not be able to receive packets from the peer, and your node will
generate packets with a spoofed source address.
If the outer protocol is IPv6, path MTU discovery for encapsulated packet may affect communication over the interface.
|July 11, 2018||OpenBSD-current|