gvpe/doc/vped.conf.5.pod

=head1 NAME

vped.conf - vpe daemon configuration file

=head1 SYNOPSIS

   udp-port = 407
   mtu = 1492
   ifname = vpn0

   node = branch1
   hostname = 1.2.3.4

   node = branch2
   hostname = www.example.net
   udp-port = 500       # this host uses a different udp-port

   node = branch3
   connect = ondemand

=head1 DESCRIPTION

The vpe config file consists of a series of lines that contain C<variable
= value> pairs. Empty lines are ignored. Comments start with a C<#> and
extend to the end of the line. They can be used on their own lines, or
after any directives. Spaces are allowed before or after the C<=> sign or
after values, but not within the variable names or values themselves.

The only exception to the above is the "on" directive that can prefix any
C<name = value> setting and will only "execute" it on the named node, or
(if the nodename starts with "!") on all nodes except the named one.

   name = value
   on branch1 loglevel = noise
   on !branch2 connect = ondemand

All settings are executed "in order", that is, later settings of the same
variable overwrite earlier ones.

=head1 ANATOMY OF A CONFIG FILE

Usually, a config file starts with global settings (like the udp port to
listen on), followed by node-specific sections that begin with a C<node =
nickname> line.

Every node that is part of the network must have a section that starts
with C<node = nickname>. The number and order of the nodes is important
and must be the same on all hosts. It is not uncommon for node sections to
be completely empty - if the default values are right.

Node-specific settings can be used at any time. If used before the first
node section they will set the default values for all following nodes.

=head1 CONFIG VARIABLES

=head2 GLOBAL SETTINGS

Global settings will affect the behaviour of the running vped daemon, that
is, they are in some sense node-specific (config files can set different
values on different nodes using C<on>), but will affect the behaviour of
the vped daemon and all connections it creates.

=over 4

=item loglevel = noise|trace|debug|info|notice|warn|error|critical

Set the logging level. Connection established messages are logged at level
C<info>, notable errors are logged with C<error>. Default is C<info>.

=item node = nickname

Not really a config setting but introduces a node section. The nickname is
used to select the right configuration section and must be passed as an
argument to the vped daemon.

=item private-key = relative-path-to-key

Sets the path (relative to the config directory) to the private key
(default: C<hostkey>). This is a printf format string so every C<%> must
be doubled. A single C<%s> is replaced by the hostname, so you could
use paths like C<hostkeys/%s> to fetch the files at the location where
C<vpectrl> puts them.

Since only the private key file of the current node is used and the
private key file should be kept secret per-host to avoid spoofings, it is
not recommended to use this feature.

=item ifpersist = yes|true|on | no|false|off

Should the tun/tap device be made persistent, that is, should the device
stay up even when vped exits? Some versions of the tunnel device have
problems sending packets when vped is restarted in persistent mode, so
if the connections can be established but you cannot send packets from
the local node, try to set this to C<off> and do an ifconfig down on the
device.

=item ifname = devname

Sets the tun interface name to the given name. The default is OS-specific
and most probably something like C<tun0>.

=item rekey = seconds

Sets the rekeying interval in seconds (default: C<3600>). Connections are
reestablished every C<rekey> seconds.

=item keepalive = seconds

Sets the keepalive probe interval in seconds (default: C<60>). After this
many seconds of inactivity the daemon will start to send keepalive probe
every 5 seconds until it receives a reply from the other end.  If no reply
is received within 30 seconds, the peer is considered unreachable and the
connection is closed.

=item mtu = bytes

Sets the maximum MTU that should be used on outgoing packets (basically
the MTU of the outgoing interface) The daemon will automatically calculate
maximum overhead (e.g. udp header size, encryption blocksize...) and pass
this information to the C<if-up> script.

Recommended values are 1500 (ethernet), 1492 (pppoe), 1472 (pptp).

This value must be the minimum of the mtu values of all hosts.

=item ip-proto = numerical-ip-protocol

Sets the protocol number to be used for the rawip protocol. This is a
global option because all hosts must use the same protocol, and since
there are no port numbers, you cannot easily run more than one vped
instance using the same protocol, nor can you share the protocol with
other programs.

The default is 47 (GRE), which has a good chance of tunneling through
firewalls (but note that the rawip protocol is not GRE compatible). Other
common choices are 50 (IPSEC, ESP), 51 (IPSEC, AH), 4 (IPIP tunnels) or 98
(ENCAP, rfc1241)

=item enable-udp = yes|true|on | no|false|off

Enable the UDPv4 transport using the C<udp-port> port
(default: C<yes>). This is a good general choice since UDP tunnels well
through many firewalls.

=item enable-rawip = yes|true|on | no|false|off

Enable the RAW IPv4 transport using the C<ip-proto> protocol
(default: C<no>). This is the best choice, since the overhead per packet
is only 38 bytes, as opposed to UDP's 58 (or TCP's 60+).

=item if-up = relative-or-absolute-path

Sets the path of a script that should be called immediately after the
network interface is initialized (but not neccessarily up). The following
environment variables are passed to it (the values are just examples):

=over 4

=item CONFBASE=/etc/vpe

The configuration base directory.

=item IFNAME=vpn0

The interface to initialize.

=item MTU=1436

The MTU to set the interface to. You can use lower values (if done
consistently on all hosts), but this is usually ineffective.

=item MAC=fe:fd:80:00:00:01

The MAC address to set the interface to. The script *must* set the
interface MAC to this value. On GNU/Linux you will most likely use this:

   ip link set $IFNAME address $MAC mtu $MTU up

=item NODENAME=branch1

The nickname of the current node, as passed to the vped daemon.

=item NODEID=1

The numerical node id of the current node. The first node mentioned in the
config file gets ID 1, the second ID 2 and so on.

=back

Here is a simple if-up script:

   #!/bin/sh
   ip link set $IFNAME address $MAC mtu $MTU up
   [ $NODENAME = branch1 ] && ip addr add 10.0.0.1 dev $IFNAME
   [ $NODENAME = branch2 ] && ip addr add 10.1.0.1 dev $IFNAME
   ip route add 10.0.0.0/8 dev $IFNAME

More complicated examples (using routing to reduce arp traffic) can be
found in the etc/ subdirectory of the distribution.

=item node-up = relative-or-absolute-path

Sets a command (default: no script) that should be called whenever a
connection is established (even on rekeying operations). In addition
to the variables passed to C<if-up> scripts, the following environment
variables will be set:

=over 4

=item DESTNODE=branch2

The name of the remote node.

=item DESTID=2

The node id of the remote node.

=item DESTIP=188.13.66.8

The numerical IP address of the remote host (vped accepts connections from
everywhere, as long as the other host can authenticate itself).

=item DESTPORT=407 # deprecated

The UDP port used by the other side.

=item STATE=UP

Node-up scripts get called with STATE=UP, node-down scripts get called
with STATE=DOWN.

=back

Here is a nontrivial example that uses nsupdate to update the name => ip
mapping in some dns zone:

   #!/bin/sh
   {
     echo update delete $DESTNODE.lowttl.example.net. a
     echo update add $DESTNODE.lowttl.example.net. 1 in a $DESTIP
     echo   
   } | nsupdate -d -k $CONFBASE:key.example.net.

=item node-down = relative-or-absolute-path

Same as C<node-up>, but gets called whenever a connection is lost.

=back

=head2 NODE SPECIFIC SETTINGS

The following settings are node-specific, that is, every node can have
different settings, even within the same vped instance. Settings that are
executed before the first node section set the defaults, settings that are
executed within a node section only apply to the given node.

=over 4

=item udp-port = port-number

Sets the port number used by the UDP protocol (default: C<407>, not
officially assigned by IANA!).

=item router-priority = positive-number

Sets the router priority of the given host (default: C<0>, disabled). If
some host tries to connect to another host without a hostname, it asks
the router host for it's IP address. The router host is the one with the
highest priority that is currently reachable. Make sure all clients always
connect to the router hosts, otherwise conencting to them is impossible.

=item connect = ondemand|never|always|disabled

Sets the connect mode (default: C<always>). It can be C<always> (always
try to establish and keep a conenction to the given host), C<never>
(nevr initiate a connection to the given host, but accept connections),
C<ondemand> (try to establish a connection on the first packet sent, and
take it down after the keepalive interval) or C<disabled> (node is bad,
don't talk to it).

=item inherit-tos = yes|true|on | no|false|off

Wether to inherit the TOS settings of packets sent to the tunnel when
sending packets to this node (default: C<yes>). If set to C<yes> then
outgoing tunnel packets will have the same TOS setting as the packets sent
to the tunnel device, which is usually what you want.

=item compress = yes|true|on | no|false|off

Wether to compress data packets sent to this host (default: C<yes>).
Compression is really cheap even on slow computers and has no size
overhead at all, so enabling this is a good idea.

=back

=head1 CONFIG DIRECTORY LAYOUT

The default (or recommended) directory layout for the config directory is:

=over 4

=item vped.conf

The config file.

=item if-up

The if-up script

=item node-up, node-down

If used the node up or node-down scripts.

=item hostkey

The private key (taken from C<hostkeys/nodename>) of the current host.

=item pubkey/nodename

The public keys of the other nodes, one file per node.

=back

=head1 SEE ALSO

vpe(5), vped(8), vpectrl(8).

=head1 AUTHOR

Marc Lehmann <vpe@plan9.de>

Revision:	1.2
Committed:	Fri Mar 28 19:46:47 2003 UTC (21 years, 2 months ago) by pcg
Branch:	MAIN
Changes since 1.1:	+1 -1 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	pcg	1.1	=head1 NAME
2
3			vped.conf - vpe daemon configuration file
4
5			=head1 SYNOPSIS
6
7			udp-port = 407
8			mtu = 1492
9			ifname = vpn0
10	pcg	1.2
11	pcg	1.1	node = branch1
12			hostname = 1.2.3.4
13
14			node = branch2
15			hostname = www.example.net
16			udp-port = 500 # this host uses a different udp-port
17
18			node = branch3
19			connect = ondemand
20
21			=head1 DESCRIPTION
22
23			The vpe config file consists of a series of lines that contain C<variable
24			= value> pairs. Empty lines are ignored. Comments start with a C<#> and
25			extend to the end of the line. They can be used on their own lines, or
26			after any directives. Spaces are allowed before or after the C<=> sign or
27			after values, but not within the variable names or values themselves.
28
29			The only exception to the above is the "on" directive that can prefix any
30			C<name = value> setting and will only "execute" it on the named node, or
31			(if the nodename starts with "!") on all nodes except the named one.
32
33			name = value
34			on branch1 loglevel = noise
35			on !branch2 connect = ondemand
36
37			All settings are executed "in order", that is, later settings of the same
38			variable overwrite earlier ones.
39
40			=head1 ANATOMY OF A CONFIG FILE
41
42			Usually, a config file starts with global settings (like the udp port to
43			listen on), followed by node-specific sections that begin with a C<node =
44			nickname> line.
45
46			Every node that is part of the network must have a section that starts
47			with C<node = nickname>. The number and order of the nodes is important
48			and must be the same on all hosts. It is not uncommon for node sections to
49			be completely empty - if the default values are right.
50
51			Node-specific settings can be used at any time. If used before the first
52			node section they will set the default values for all following nodes.
53
54			=head1 CONFIG VARIABLES
55
56			=head2 GLOBAL SETTINGS
57
58			Global settings will affect the behaviour of the running vped daemon, that
59			is, they are in some sense node-specific (config files can set different
60			values on different nodes using C<on>), but will affect the behaviour of
61			the vped daemon and all connections it creates.
62
63			=over 4
64
65			=item loglevel = noise\|trace\|debug\|info\|notice\|warn\|error\|critical
66
67			Set the logging level. Connection established messages are logged at level
68			C<info>, notable errors are logged with C<error>. Default is C<info>.
69
70			=item node = nickname
71
72			Not really a config setting but introduces a node section. The nickname is
73			used to select the right configuration section and must be passed as an
74			argument to the vped daemon.
75
76			=item private-key = relative-path-to-key
77
78			Sets the path (relative to the config directory) to the private key
79			(default: C<hostkey>). This is a printf format string so every C<%> must
80			be doubled. A single C<%s> is replaced by the hostname, so you could
81			use paths like C<hostkeys/%s> to fetch the files at the location where
82			C<vpectrl> puts them.
83
84			Since only the private key file of the current node is used and the
85			private key file should be kept secret per-host to avoid spoofings, it is
86			not recommended to use this feature.
87
88			=item ifpersist = yes\|true\|on \| no\|false\|off
89
90			Should the tun/tap device be made persistent, that is, should the device
91			stay up even when vped exits? Some versions of the tunnel device have
92			problems sending packets when vped is restarted in persistent mode, so
93			if the connections can be established but you cannot send packets from
94			the local node, try to set this to C<off> and do an ifconfig down on the
95			device.
96
97			=item ifname = devname
98
99			Sets the tun interface name to the given name. The default is OS-specific
100			and most probably something like C<tun0>.
101
102			=item rekey = seconds
103
104			Sets the rekeying interval in seconds (default: C<3600>). Connections are
105			reestablished every C<rekey> seconds.
106
107			=item keepalive = seconds
108
109			Sets the keepalive probe interval in seconds (default: C<60>). After this
110			many seconds of inactivity the daemon will start to send keepalive probe
111			every 5 seconds until it receives a reply from the other end. If no reply
112			is received within 30 seconds, the peer is considered unreachable and the
113			connection is closed.
114
115			=item mtu = bytes
116
117			Sets the maximum MTU that should be used on outgoing packets (basically
118			the MTU of the outgoing interface) The daemon will automatically calculate
119			maximum overhead (e.g. udp header size, encryption blocksize...) and pass
120			this information to the C<if-up> script.
121
122			Recommended values are 1500 (ethernet), 1492 (pppoe), 1472 (pptp).
123
124			This value must be the minimum of the mtu values of all hosts.
125
126			=item ip-proto = numerical-ip-protocol
127
128			Sets the protocol number to be used for the rawip protocol. This is a
129			global option because all hosts must use the same protocol, and since
130			there are no port numbers, you cannot easily run more than one vped
131			instance using the same protocol, nor can you share the protocol with
132			other programs.
133
134			The default is 47 (GRE), which has a good chance of tunneling through
135			firewalls (but note that the rawip protocol is not GRE compatible). Other
136			common choices are 50 (IPSEC, ESP), 51 (IPSEC, AH), 4 (IPIP tunnels) or 98
137			(ENCAP, rfc1241)
138
139			=item enable-udp = yes\|true\|on \| no\|false\|off
140
141			Enable the UDPv4 transport using the C<udp-port> port
142			(default: C<yes>). This is a good general choice since UDP tunnels well
143			through many firewalls.
144
145			=item enable-rawip = yes\|true\|on \| no\|false\|off
146
147			Enable the RAW IPv4 transport using the C<ip-proto> protocol
148			(default: C<no>). This is the best choice, since the overhead per packet
149			is only 38 bytes, as opposed to UDP's 58 (or TCP's 60+).
150
151			=item if-up = relative-or-absolute-path
152
153			Sets the path of a script that should be called immediately after the
154			network interface is initialized (but not neccessarily up). The following
155			environment variables are passed to it (the values are just examples):
156
157			=over 4
158
159			=item CONFBASE=/etc/vpe
160
161			The configuration base directory.
162
163			=item IFNAME=vpn0
164
165			The interface to initialize.
166
167			=item MTU=1436
168
169			The MTU to set the interface to. You can use lower values (if done
170			consistently on all hosts), but this is usually ineffective.
171
172			=item MAC=fe:fd:80:00:00:01
173
174			The MAC address to set the interface to. The script must set the
175			interface MAC to this value. On GNU/Linux you will most likely use this:
176
177			ip link set $IFNAME address $MAC mtu $MTU up
178
179			=item NODENAME=branch1
180
181			The nickname of the current node, as passed to the vped daemon.
182
183			=item NODEID=1
184
185			The numerical node id of the current node. The first node mentioned in the
186			config file gets ID 1, the second ID 2 and so on.
187
188			=back
189
190			Here is a simple if-up script:
191
192			#!/bin/sh
193			ip link set $IFNAME address $MAC mtu $MTU up
194			[ $NODENAME = branch1 ] && ip addr add 10.0.0.1 dev $IFNAME
195			[ $NODENAME = branch2 ] && ip addr add 10.1.0.1 dev $IFNAME
196			ip route add 10.0.0.0/8 dev $IFNAME
197
198			More complicated examples (using routing to reduce arp traffic) can be
199			found in the etc/ subdirectory of the distribution.
200
201			=item node-up = relative-or-absolute-path
202
203			Sets a command (default: no script) that should be called whenever a
204			connection is established (even on rekeying operations). In addition
205			to the variables passed to C<if-up> scripts, the following environment
206			variables will be set:
207
208			=over 4
209
210			=item DESTNODE=branch2
211
212			The name of the remote node.
213
214			=item DESTID=2
215
216			The node id of the remote node.
217
218			=item DESTIP=188.13.66.8
219
220			The numerical IP address of the remote host (vped accepts connections from
221			everywhere, as long as the other host can authenticate itself).
222
223			=item DESTPORT=407 # deprecated
224
225			The UDP port used by the other side.
226
227			=item STATE=UP
228
229			Node-up scripts get called with STATE=UP, node-down scripts get called
230			with STATE=DOWN.
231
232			=back
233
234			Here is a nontrivial example that uses nsupdate to update the name => ip
235			mapping in some dns zone:
236
237			#!/bin/sh
238			{
239			echo update delete $DESTNODE.lowttl.example.net. a
240			echo update add $DESTNODE.lowttl.example.net. 1 in a $DESTIP
241			echo
242			} \| nsupdate -d -k $CONFBASE:key.example.net.
243
244			=item node-down = relative-or-absolute-path
245
246			Same as C<node-up>, but gets called whenever a connection is lost.
247
248			=back
249
250			=head2 NODE SPECIFIC SETTINGS
251
252			The following settings are node-specific, that is, every node can have
253			different settings, even within the same vped instance. Settings that are
254			executed before the first node section set the defaults, settings that are
255			executed within a node section only apply to the given node.
256
257			=over 4
258
259			=item udp-port = port-number
260
261			Sets the port number used by the UDP protocol (default: C<407>, not
262			officially assigned by IANA!).
263
264			=item router-priority = positive-number
265
266			Sets the router priority of the given host (default: C<0>, disabled). If
267			some host tries to connect to another host without a hostname, it asks
268			the router host for it's IP address. The router host is the one with the
269			highest priority that is currently reachable. Make sure all clients always
270			connect to the router hosts, otherwise conencting to them is impossible.
271
272			=item connect = ondemand\|never\|always\|disabled
273
274			Sets the connect mode (default: C<always>). It can be C<always> (always
275			try to establish and keep a conenction to the given host), C<never>
276			(nevr initiate a connection to the given host, but accept connections),
277			C<ondemand> (try to establish a connection on the first packet sent, and
278			take it down after the keepalive interval) or C<disabled> (node is bad,
279			don't talk to it).
280
281			=item inherit-tos = yes\|true\|on \| no\|false\|off
282
283			Wether to inherit the TOS settings of packets sent to the tunnel when
284			sending packets to this node (default: C<yes>). If set to C<yes> then
285			outgoing tunnel packets will have the same TOS setting as the packets sent
286			to the tunnel device, which is usually what you want.
287
288			=item compress = yes\|true\|on \| no\|false\|off
289
290			Wether to compress data packets sent to this host (default: C<yes>).
291			Compression is really cheap even on slow computers and has no size
292			overhead at all, so enabling this is a good idea.
293
294			=back
295
296			=head1 CONFIG DIRECTORY LAYOUT
297
298			The default (or recommended) directory layout for the config directory is:
299
300			=over 4
301
302			=item vped.conf
303
304			The config file.
305
306			=item if-up
307
308			The if-up script
309
310			=item node-up, node-down
311
312			If used the node up or node-down scripts.
313
314			=item hostkey
315
316			The private key (taken from C<hostkeys/nodename>) of the current host.
317
318			=item pubkey/nodename
319
320			The public keys of the other nodes, one file per node.
321
322			=back
323
324			=head1 SEE ALSO
325
326			vpe(5), vped(8), vpectrl(8).
327
328			=head1 AUTHOR
329
330			Marc Lehmann <vpe@plan9.de>
331