man/man4/ng_iface.4

.\" $MidnightBSD$
.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
.\" All rights reserved.
.\"
.\" Subject to the following obligations and disclaimer of warranty, use and
.\" redistribution of this software, in source or object code forms, with or
.\" without modifications are expressly permitted by Whistle Communications;
.\" provided, however, that:
.\" 1. Any and all reproductions of the source or object code must include the
.\"    copyright notice above and the following disclaimer of warranties; and
.\" 2. No rights are granted, in any manner or form, to use Whistle
.\"    Communications, Inc. trademarks, including the mark "WHISTLE
.\"    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
.\"    such appears in the above copyright notice or in the software.
.\"
.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER 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 WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
.\" OF SUCH DAMAGE.
.\"
.\" Author: Archie Cobbs <archie@FreeBSD.org>
.\"
.\" $FreeBSD: stable/10/share/man/man4/ng_iface.4 242997 2012-11-13 20:41:36Z joel $
.\" $Whistle: ng_iface.8,v 1.5 1999/01/25 23:46:26 archie Exp $
.\"
.Dd October 28, 2005
.Dt NG_IFACE 4
.Os
.Sh NAME
.Nm ng_iface
.Nd interface netgraph node type
.Sh SYNOPSIS
.In netgraph/ng_iface.h
.Sh DESCRIPTION
An
.Nm iface
node is both a netgraph node and a system networking interface.
When an
.Nm iface
node is created, a new interface appears which is accessible via
.Xr ifconfig 8 .
.Nm Iface
node interfaces are named
.Dv ng0 ,
.Dv ng1 ,
etc.
When a node is shutdown, the corresponding interface is removed
and the interface name becomes available for reuse by future
.Nm iface
nodes; new nodes always take the first unused interface.
The node itself is assigned the same name as its interface, unless the name
already exists, in which case the node remains unnamed.
.Pp
An
.Nm iface
node has a single hook corresponding to each supported protocol.
Packets transmitted via the interface flow out the corresponding
protocol-specific hook.
Similarly, packets received on a hook appear on the interface as
packets received into the corresponding protocol stack.
The currently supported protocols are IP, IPv6, AppleTalk, IPX, ATM,
NATM, and NS.
.Pp
An
.Nm iface
node can be configured as a point-to-point interface or a broadcast interface.
The configuration can only be changed when the interface is down.
The default mode is point-to-point.
.Pp
.Nm Iface
nodes support the Berkeley Packet Filter (BPF).
.Sh HOOKS
This node type supports the following hooks:
.Bl -tag -width ".Va inet6"
.It Va inet
Transmission and reception of IP packets.
.It Va inet6
Transmission and reception of IPv6 packets.
.It Va atalk
Transmission and reception of AppleTalk packets.
.It Va ipx
Transmission and reception of IPX packets.
.It Va atm
Transmission and reception of ATM packets.
.It Va natm
Transmission and reception of NATM packets.
.It Va ns
Transmission and reception of NS packets.
.El
.Sh CONTROL MESSAGES
This node type supports the generic control messages, plus the following:
.Bl -tag -width foo
.It Dv NGM_IFACE_GET_IFNAME Pq Ic getifname
Returns the name of the associated interface as a
.Dv NUL Ns -terminated
.Tn ASCII
string.
Normally this is the same as the name of the node.
.It Dv NGM_IFACE_GET_IFINDEX Pq Ic getifindex
Returns the global index of the associated interface as a 32 bit integer.
.It Dv NGM_IFACE_POINT2POINT Pq Ic point2point
Set the interface to point-to-point mode.
The interface must not currently be up.
.It Dv NGM_IFACE_BROADCAST Pq Ic broadcast
Set the interface to broadcast mode.
The interface must not currently be up.
.It Dv NGM_CISCO_GET_IPADDR Pq Ic getipaddr
This message is defined by the
.Xr ng_cisco 4
node type; see
.Xr ng_cisco 4
for a description.
.El
.Sh SHUTDOWN
This node shuts down upon receipt of a
.Dv NGM_SHUTDOWN
control message.
The associated interface is removed and becomes available
for use by future
.Nm iface
nodes.
.Pp
Unlike most other node types, an
.Nm iface
node does
.Em not
go away when all hooks have been disconnected; rather, and explicit
.Dv NGM_SHUTDOWN
control message is required.
.Sh ALTQ Support
The
.Nm
interface supports ALTQ bandwidth management feature.
However,
.Nm
is a special case, since it is not a physical interface with limited bandwidth.
One should not turn ALTQ on
.Nm
if the latter corresponds to some tunneled connection, e.g.\& PPPoE or PPTP.
In this case, ALTQ should be configured on the interface that is used to
transmit the encapsulated packets.
In case when your graph ends up with some kind of serial line, either
synchronous or modem, the
.Nm
is the right place to turn ALTQ on.
.Sh SEE ALSO
.Xr altq 4 ,
.Xr bpf 4 ,
.Xr netgraph 4 ,
.Xr ng_cisco 4 ,
.Xr ifconfig 8 ,
.Xr ngctl 8
.Sh HISTORY
The
.Nm iface
node type was implemented in
.Fx 4.0 .
.Sh AUTHORS
.An Archie Cobbs Aq archie@FreeBSD.org
Revision:	11734
Committed:	Mon Jul 9 23:26:56 2018 UTC (5 years, 9 months ago) by laffer1
File size:	5964 byte(s)
Log Message:	update more
#	Content
1	.\" $MidnightBSD$
2	.\" Copyright (c) 1996-1999 Whistle Communications, Inc.
3	.\" All rights reserved.
4	.\"
5	.\" Subject to the following obligations and disclaimer of warranty, use and
6	.\" redistribution of this software, in source or object code forms, with or
7	.\" without modifications are expressly permitted by Whistle Communications;
8	.\" provided, however, that:
9	.\" 1. Any and all reproductions of the source or object code must include the
10	.\" copyright notice above and the following disclaimer of warranties; and
11	.\" 2. No rights are granted, in any manner or form, to use Whistle
12	.\" Communications, Inc. trademarks, including the mark "WHISTLE
13	.\" COMMUNICATIONS" on advertising, endorsements, or otherwise except as
14	.\" such appears in the above copyright notice or in the software.
15	.\"
16	.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
17	.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
18	.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
19	.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
20	.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
21	.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
22	.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
23	.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
24	.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
25	.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
26	.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
27	.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
28	.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
29	.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30	.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31	.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
32	.\" OF SUCH DAMAGE.
33	.\"
34	.\" Author: Archie Cobbs <archie@FreeBSD.org>
35	.\"
36	.\" $FreeBSD: stable/10/share/man/man4/ng_iface.4 242997 2012-11-13 20:41:36Z joel $
37	.\" $Whistle: ng_iface.8,v 1.5 1999/01/25 23:46:26 archie Exp $
38	.\"
39	.Dd October 28, 2005
40	.Dt NG_IFACE 4
41	.Os
42	.Sh NAME
43	.Nm ng_iface
44	.Nd interface netgraph node type
45	.Sh SYNOPSIS
46	.In netgraph/ng_iface.h
47	.Sh DESCRIPTION
48	An
49	.Nm iface
50	node is both a netgraph node and a system networking interface.
51	When an
52	.Nm iface
53	node is created, a new interface appears which is accessible via
54	.Xr ifconfig 8 .
55	.Nm Iface
56	node interfaces are named
57	.Dv ng0 ,
58	.Dv ng1 ,
59	etc.
60	When a node is shutdown, the corresponding interface is removed
61	and the interface name becomes available for reuse by future
62	.Nm iface
63	nodes; new nodes always take the first unused interface.
64	The node itself is assigned the same name as its interface, unless the name
65	already exists, in which case the node remains unnamed.
66	.Pp
67	An
68	.Nm iface
69	node has a single hook corresponding to each supported protocol.
70	Packets transmitted via the interface flow out the corresponding
71	protocol-specific hook.
72	Similarly, packets received on a hook appear on the interface as
73	packets received into the corresponding protocol stack.
74	The currently supported protocols are IP, IPv6, AppleTalk, IPX, ATM,
75	NATM, and NS.
76	.Pp
77	An
78	.Nm iface
79	node can be configured as a point-to-point interface or a broadcast interface.
80	The configuration can only be changed when the interface is down.
81	The default mode is point-to-point.
82	.Pp
83	.Nm Iface
84	nodes support the Berkeley Packet Filter (BPF).
85	.Sh HOOKS
86	This node type supports the following hooks:
87	.Bl -tag -width ".Va inet6"
88	.It Va inet
89	Transmission and reception of IP packets.
90	.It Va inet6
91	Transmission and reception of IPv6 packets.
92	.It Va atalk
93	Transmission and reception of AppleTalk packets.
94	.It Va ipx
95	Transmission and reception of IPX packets.
96	.It Va atm
97	Transmission and reception of ATM packets.
98	.It Va natm
99	Transmission and reception of NATM packets.
100	.It Va ns
101	Transmission and reception of NS packets.
102	.El
103	.Sh CONTROL MESSAGES
104	This node type supports the generic control messages, plus the following:
105	.Bl -tag -width foo
106	.It Dv NGM_IFACE_GET_IFNAME Pq Ic getifname
107	Returns the name of the associated interface as a
108	.Dv NUL Ns -terminated
109	.Tn ASCII
110	string.
111	Normally this is the same as the name of the node.
112	.It Dv NGM_IFACE_GET_IFINDEX Pq Ic getifindex
113	Returns the global index of the associated interface as a 32 bit integer.
114	.It Dv NGM_IFACE_POINT2POINT Pq Ic point2point
115	Set the interface to point-to-point mode.
116	The interface must not currently be up.
117	.It Dv NGM_IFACE_BROADCAST Pq Ic broadcast
118	Set the interface to broadcast mode.
119	The interface must not currently be up.
120	.It Dv NGM_CISCO_GET_IPADDR Pq Ic getipaddr
121	This message is defined by the
122	.Xr ng_cisco 4
123	node type; see
124	.Xr ng_cisco 4
125	for a description.
126	.El
127	.Sh SHUTDOWN
128	This node shuts down upon receipt of a
129	.Dv NGM_SHUTDOWN
130	control message.
131	The associated interface is removed and becomes available
132	for use by future
133	.Nm iface
134	nodes.
135	.Pp
136	Unlike most other node types, an
137	.Nm iface
138	node does
139	.Em not
140	go away when all hooks have been disconnected; rather, and explicit
141	.Dv NGM_SHUTDOWN
142	control message is required.
143	.Sh ALTQ Support
144	The
145	.Nm
146	interface supports ALTQ bandwidth management feature.
147	However,
148	.Nm
149	is a special case, since it is not a physical interface with limited bandwidth.
150	One should not turn ALTQ on
151	.Nm
152	if the latter corresponds to some tunneled connection, e.g.\& PPPoE or PPTP.
153	In this case, ALTQ should be configured on the interface that is used to
154	transmit the encapsulated packets.
155	In case when your graph ends up with some kind of serial line, either
156	synchronous or modem, the
157	.Nm
158	is the right place to turn ALTQ on.
159	.Sh SEE ALSO
160	.Xr altq 4 ,
161	.Xr bpf 4 ,
162	.Xr netgraph 4 ,
163	.Xr ng_cisco 4 ,
164	.Xr ifconfig 8 ,
165	.Xr ngctl 8
166	.Sh HISTORY
167	The
168	.Nm iface
169	node type was implemented in
170	.Fx 4.0 .
171	.Sh AUTHORS
172	.An Archie Cobbs Aq archie@FreeBSD.org