ng_gif(4)
NAME
ng_gif - generic tunnel interface netgraph node type
SYNOPSIS
#include <netgraph/ng_gif.h>
DESCRIPTION
- The ng_gif netgraph node type allows gif(4) interfaces to
- interact with the netgraph(4) networking subsystem. Once the ng_gif mod
- ule is loaded in the kernel, a node is automatically created for each
- gif(4) interface in the system. Each node will attempt to name itself with
- the same name as the associated interface. All ng_gif nodes are persis
- tent for as long as the interface itself exists.
- Two hooks are supported: lower and orphans. The hook name
- divert may be used as an alias for lower, and is provided for compatibili
- ty with ng_ether(4). In reality the two names represent the same
- hook.
- The lower hook is a connection to the raw gif(4) device.
- When connected, all incoming packets are diverted out this hook. Writing to
- this hook results in a raw encapsulated packet being transmitted by
- the device. Normal outgoing packets are not affected by lower being con
- nected.
- The orphans hook is equivalent to lower, except that only
- unrecognized packets (that would otherwise be discarded) are written to
- the hook, and normal incoming traffic is unaffected. At most one of or
- phans and lower may be connected at any time.
- In all cases, frames are raw packets with the address family
- of the packet attached to the front.
- When no hooks are connected, packets flow normally upwards
- and downwards.
HOOKS
This node type supports the following hooks:
lower Connection to the lower device link layer.
- orphans Like lower, but only receives unrecognized
- packets.
CONTROL MESSAGES
This node type supports only the generic control messages.
EXAMPLES
- This command dumps all unrecognized packets received by the
- gif0 interface to standard output decoded in hex and ASCII:
- nghook -a gif0: orphans
SEE ALSO
AUTHORS
- Brooks Davis <brooks@FreeBSD.org>
- BSD September 18, 2001