xref: /freebsd/share/man/man4/ng_iface.4 (revision 2a4a1db342263067035ce69a4017c645da63455d)
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33.\" Author: Archie Cobbs <archie@FreeBSD.org>
34.\"
35.\" $FreeBSD$
36.\" $Whistle: ng_iface.8,v 1.5 1999/01/25 23:46:26 archie Exp $
37.\"
38.Dd January 19, 1999
39.Dt NG_IFACE 4
40.Os
41.Sh NAME
42.Nm ng_iface
43.Nd interface netgraph node type
44.Sh SYNOPSIS
45.In netgraph/ng_iface.h
46.Sh DESCRIPTION
47An
48.Nm iface
49node is both a netgraph node and a system networking interface.  When an
50.Nm iface
51node is created, a new interface appears which is accessible via
52.Xr ifconfig 8 .
53.Nm Iface
54node interfaces are named
55.Dv ng0 ,
56.Dv ng1 ,
57etc.
58When a node is shutdown, the corresponding interface is removed
59and the interface name becomes available for reuse by future
60.Nm iface
61nodes; new nodes always take the first unused interface.
62The node itself is assigned the same name as its interface, unless the name
63already exists, in which case the node remains unnamed.
64.Pp
65An
66.Nm iface
67node has a single hook corresponding to each supported protocol.
68Packets transmitted via the interface flow out the corresponding
69protocol-specific hook.
70Similarly, packets received on a hook appear on the interface as
71packets received into the corresponding protocol stack.
72The currently supported protocols are IP, IPv6, AppleTalk, IPX, ATM,
73NATM, and NS.
74.Pp
75An
76.Nm iface
77node be configured as a point-to-point interface or a broadcast interface.
78The configuration can only be changed when the interface is down.
79The default mode is point-to-point.
80.Pp
81.Nm Iface
82nodes support the Berkeley Packet Filter (BPF).
83.Sh HOOKS
84This node type supports the following hooks:
85.Pp
86.Bl -tag -width foobar
87.It Dv inet
88Transmission and reception of IP packets.
89.It Dv inet6
90Transmission and reception of IPv6 packets.
91.It Dv atalk
92Transmission and reception of AppleTalk packets.
93.It Dv ipx
94Transmission and reception of IPX packets.
95.It Dv atm
96Transmission and reception of ATM packets.
97.It Dv natm
98Transmission and reception of NATM packets.
99.It Dv ns
100Transmission and reception of NS packets.
101.El
102.Sh CONTROL MESSAGES
103This node type supports the generic control messages, plus the following:
104.Bl -tag -width foo
105.It Dv NGM_IFACE_GET_IFNAME
106Returns the name of the interface corresponding to this node in a
107.Dv "struct ng_iface_ifname" :
108.Bd -literal -offset 4n
109struct ng_iface_ifname {
110  char  ngif_name[NG_IFACE_IFACE_NAME_MAX + 1];
111};
112.Ed
113.It Dv NGM_IFACE_POINT2POINT
114Set the interface to point-to-point mode.
115The interface must not currently be up.
116.It Dv NGM_IFACE_BROADCAST
117Set the interface to broadcast mode.
118The interface must not currently be up.
119.It Dv NGM_CISCO_GET_IPADDR
120This message is defined by the
121.Xr ng_cisco 4
122node type; see
123.Xr ng_cisco 4
124for a description.
125.El
126.Sh SHUTDOWN
127This node shuts down upon receipt of a
128.Dv NGM_SHUTDOWN
129control message.  The associated interface is removed and becomes available
130for use by future
131.Nm iface
132nodes.
133.Pp
134Unlike most other node types, an
135.Nm iface
136node does
137.Em not
138go away when all hooks have been disconnected; rather, and explicit
139.Dv NGM_SHUTDOWN
140control message is required.
141.Sh SEE ALSO
142.Xr bpf 4 ,
143.Xr netgraph 4 ,
144.Xr ng_cisco 4 ,
145.Xr ifconfig 8 ,
146.Xr ngctl 8
147.Sh HISTORY
148The
149.Nm iface
150node type was implemented in
151.Fx 4.0 .
152.Sh AUTHORS
153.An Archie Cobbs Aq archie@FreeBSD.org
154