xref: /freebsd/share/man/man4/ng_ether.4 (revision d905b0b639f0265cd4379c18e4b462cbaf6b331c)

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.\" Author: Archie Cobbs <archie@whistle.com>
.\"
.\" $FreeBSD$
.\"
.Dd January 25, 2000
.Dt NG_ETHER 8
.Os FreeBSD
.Sh NAME
.Nm ng_ether
.Nd Ethernet netgraph node type
.Sh SYNOPSIS
.Fd #include <netgraph/ng_ether.h>
.Sh DESCRIPTION
The
.Nm ether
netgraph node type allows Ethernet interfaces to interact with
the
.Xr netgraph 4
networking subsystem.  The kernel must be compiled with
.Bd -literal
    options NETGRAPH
.Ed
.Pp
for this functionality to be enabled.
This causes a netgraph node to be automatically created for each Ethernet
interface in the system.  The node will have a name equal to
the name of the interface, and it will be persistent.
.Pp
The Ethernet interface continues to function normally until a connection
is made to one of the two supported hooks,
.Dv orphans
or
.Dv divert .
The
.Dv orphans
hook is used to receive Ethernet frames received by the device and
having an unknown or unsupported Ethertype.
The
.Dv divert
hook is used to divert
.Em all
Ethernet frames received by the device; the interface will otherwise
appear to go silent until this hook is disconnected.
.Pp
Either hook may be used to transmit Ethernet frames by transmitting packets
to the hook.  In all cases, frames are raw Ethernet frames with the standard
14 byte Ethernet header (but no checksum).
.Sh HOOKS
This node type supports the following hooks:
.Pp
.Bl -tag -width orphans
.It Dv orphans
This hook transmits Ethernet frames received by the device and
having an unknown or unsupported Ethertype.  Frames received on
this hook are written as-is out on the wire.
.It Dv divert
When connected, this hook transmits all Ethernet frames received by the device.
Frames received on this hook are written as-is out on the wire.
.El
.Sh CONTROL MESSAGES
This node type supports only the generic control messages.
.Sh SHUTDOWN
This node is persistent.  Upon receipt of a
.Dv NGM_SHUTDOWN
control message, all hooks are disconnected.
.Sh EXAMPLE
This command will dump all packets received by the
.Dv fxp0
interface to standard output as decoded hex and ASCII:
.Bl -literal

    nghook -a fxp0: divert
.El
.Sh SEE ALSO
.Xr arp 4 ,
.Xr netgraph 4 ,
.Xr netintro 4 ,
.Xr ifconfig 8 ,
.Xr nghook 8 ,
.Xr ngctl 8
.Sh AUTHOR
.An Julian Elischer Aq julian@FreeBSD.org