1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
.\" $OpenBSD: pppoe.4,v 1.1 2004/11/29 22:56:04 canacar Exp $
.\" $NetBSD: pppoe.4,v 1.26 2003/10/02 07:06:36 wiz Exp $
.\"
.\" Copyright (c) 2002 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Martin Husemann <martin@NetBSD.org>.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 3. All advertising materials mentioning features or use of this software
.\" must display the following acknowledgement:
.\" This product includes software developed by the NetBSD
.\" Foundation, Inc. and its contributors.
.\" 4. Neither the name of The NetBSD Foundation nor the names of its
.\" contributors may be used to endorse or promote products derived
.\" from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON 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 ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd October 1, 2003
.Dt PPPOE 4
.Os
.Sh NAME
.Nm pppoe
.Nd PPP over Ethernet protocol network interface
.Sh SYNOPSIS
.Nm pseudo-device pppoe
.Sh DESCRIPTION
The
.Nm
interface encapsulates
.Em Point-to-Point Protocol (PPP)
packets inside Ethernet frames as defined by RFC 2516.
.Pp
This is often used to connect a router via a DSL modem to
an access concentrator.
The
.Nm
interface does not by itself transmit or receive frames,
but needs an Ethernet interface to do so.
This Ethernet interface is connected to the
.Nm
interface via
.Xr ifconfig 8 .
The Ethernet interface needs to be marked UP, but does not need to have an
IP address.
.Pp
There are two basic modes of operation, controlled via the
.Em link1
switch.
The default mode,
.Em link1
not being set, tries to keep the configured session open all the
time.
If the session is disconnected, a new connection attempt is started
immediately.
The
.Dq dial on demand
mode, selected by setting
.Em link1 ,
only establishes a connection when data is being sent to the interface.
.Pp
If the kernel is compiled with options
.Dv PPPOE_SERVER ,
there are two modes of connection, controlled via the
.Em link0
switch.
The default mode,
.Em link0
not being set, is client mode.
The
.Dq PPPoE server
mode, selected by setting
.Em link0 ,
is to wait for incoming PPPoE session.
.Pp
Before a
.Nm
interface is usable, it needs to be configured.
The following steps are necessary:
.Bl -bullet
.It
Create the interface.
.It
Connect an Ethernet interface.
This interface is used for the physical communication.
As noted above it must be marked UP, but need not have an IP address.
.It
Configure authentication.
The PPP session needs to identify the client to the peer.
For more details on the available options see
.Xr spppcontrol 8 .
.El
.Pp
This all is typically accomplished using an
.Pa /etc/ifconfig.pppoe0
file.
.Sh EXAMPLES
A typical
.Pa /etc/hostname.pppoe0
file looks like this:
.Bd -literal -offset indent
pppoedev ne0
! /sbin/ifconfig ne0 up
! /sbin/spppcontrol $int myauthproto=pap myauthname=testcaller \e
myauthkey=donttell
! /sbin/ifconfig $int inet 0.0.0.0 0.0.0.1 netmask 0xffffffff
! /sbin/route add default 0.0.0.1
up
.Ed
.Pp
Since this is a PPP interface, the addresses assigned to the interface
may change during PPP negotiation.
There is no fine grained control available for deciding
which addresses are acceptable and which are not.
For the local side and the remote address there is exactly one choice:
hard coded address or wildcard.
If a real address is assigned to one side of the connection,
PPP negotiation will only agree to exactly this address.
If one side is wildcarded,
every address suggested by the peer will be accepted.
.Pp
To wildcard the local address set it to 0.0.0.0, to wildcard the remote
address set it to 0.0.0.1.
.Sh OPTIONS
A
.Nm
enabled kernel will not interfere with other
.Nm PPPoE
implementations running on the same machine.
Under special circumstances
(details below) this is not desirable, so the
.Nm
driver can be told to kill all unknown
.Nm PPPoE
sessions received by the Ethernet interface used for a configured
.Nm
interface.
To do this,
add the following to your kernel config file:
.Pp
.Dl options PPPOE_TERM_UNKNOWN_SESSIONS
.Pp
Note that this will break all userland
.Nm PPPoE
implementations using the same Ethernet interface!
.Pp
This option is only useful if you have a static IP address assigned and
your ISP does not use LCP echo requests to monitor the link status.
After a crash or power failure the peer device still tries to send data to
the no longer active session on your computer, and might refuse to
reestablish a new connection, because there already is an open session.
On receipt of such packets, the
.Nm
driver with this option set will send a PADT packet
(request to terminate the session).
The peer will immediately disconnect
the orphaned session and allow a new one to be established.
.Sh SEE ALSO
.Xr hostname.if 5 ,
.Xr ifconfig 8 ,
.Xr ppp 8 ,
.Xr pppoe 8 ,
.Xr spppcontrol 8
.Rs
.%R RFC 2516
.%T A Method for Transmitting PPP Over Ethernet (PPPoE)
.%D February 1999
.Re
.Sh HISTORY
The
.Nm
device appeared in
.Ox 3.7 .
.Sh BUGS
This implementation is client side only.
.Pp
It is important to specify
.Dq Li netmask 0xffffffff
to
.Xr ifconfig 8 .
If the netmask is unspecified, it will be set to 8 when 0.0.0.0 is
configured to the interface, and it will persist after negotiation.
|