ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/gvpe/doc/vped.conf.pod
Revision: 1.2
Committed: Mon Mar 24 15:20:24 2003 UTC (21 years, 2 months ago) by pcg
Branch: MAIN
Changes since 1.1: +15 -15 lines
Log Message:
*** empty log message ***

File Contents

# 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    
11     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 pcg 1.2 name = value
34     on branch1 loglevel = noise
35     on !branch2 connect = ondemand
36 pcg 1.1
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|no
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 if-up = relative-or-absolute-path
127    
128     Sets the path of a script that should be called immediately after the
129     network interface is initialized (but not neccessarily up). The following
130     environment variables are passed to it (the values are just examples):
131    
132     =over 4
133    
134     =item CONFBASE=/etc/vpe
135    
136     The configuration base directory.
137    
138     =item IFNAME=vpn0
139    
140     The interface to initialize.
141    
142     =item MTU=1436
143    
144     The MTU to set the interface to. You can use lower values (if done
145     consistently on all hosts), but this is usually ineffective.
146    
147     =item MAC=fe:fd:80:00:00:01
148    
149     The MAC address to set the interface to. The script *must* set the
150     interface MAC to this value. On GNU/Linux you will most likely use this:
151    
152 pcg 1.2 ip link set $IFNAME address $MAC mtu $MTU up
153 pcg 1.1
154     =item NODENAME=branch1
155    
156     The nickname of the current node, as passed to the vped daemon.
157    
158     =item NODEID=1
159    
160     The numerical node id of the current node. The first node mentioned in the
161     config file gets ID 1, the second ID 2 and so on.
162    
163     =back
164    
165     Here is a simple if-up script:
166    
167 pcg 1.2 #!/bin/sh
168     ip link set $IFNAME address $MAC mtu $MTU up
169     [ $NODENAME = branch1 ] && ip addr add 10.0.0.1 dev $IFNAME
170     [ $NODENAME = branch2 ] && ip addr add 10.1.0.1 dev $IFNAME
171     ip route add 10.0.0.0/8 dev $IFNAME
172 pcg 1.1
173     More complicated examples (using routing to reduce arp traffic) can be
174     found in the etc/ subdirectory of the distribution.
175    
176     =item node-up = relative-or-absolute-path
177    
178     Sets a command (default: no script) that should be called whenever a
179     connection is established (even on rekeying operations). In addition
180     to the variables passed to C<if-up> scripts, the following environment
181     variables will be set:
182    
183     =over 4
184    
185     =item DESTNODE=branch2
186    
187     The name of the remote node.
188    
189     =item DESTID=2
190    
191     The node id of the remote node.
192    
193     =item DESTIP=188.13.66.8
194    
195     The numerical IP address of the remote host (vped accepts connections from
196     everywhere, as long as the other host can authenticate itself).
197    
198     =item DESTPORT=407 # deprecated
199    
200     The UDP port used by the other side.
201    
202     =item STATE=UP
203    
204     Node-up scripts get called with STATE=UP, node-down scripts get called
205     with STATE=DOWN.
206    
207     =back
208    
209     Here is a nontrivial example that uses nsupdate to update the name => ip
210     mapping in some dns zone:
211    
212 pcg 1.2 #!/bin/sh
213     {
214     echo update delete $DESTNODE.lowttl.example.net. a
215     echo update add $DESTNODE.lowttl.example.net. 1 in a $DESTIP
216     echo
217     } | nsupdate -d -k $CONFBASE:key.example.net.
218 pcg 1.1
219     =item node-down = relative-or-absolute-path
220    
221     Same as C<node-up>, but gets called whenever a connection is lost.
222    
223     =back
224    
225     =head2 NODE SPECIFIC SETTINGS
226    
227     The following settings are node-specific, that is, every node can have
228     different settings, even within the same vped instance. Settings that are
229     executed before the first node section set the defaults, settings that are
230     executed within a node section only apply to the given node.
231    
232     =over 4
233    
234     =item udp-port = port-number
235    
236     Sets the port number used by the UDP protocol (default: C<407>, not
237     officially assigned by IANA!).
238    
239     =item router-priority = positive-number
240    
241     Sets the router priority of the given host (default: C<0>, disabled). If
242     some host tries to connect to another host without a hostname, it asks
243     the router host for it's IP address. The router host is the one with the
244     highest priority that is currently reachable. Make sure all clients always
245     connect to the router hosts, otherwise conencting to them is impossible.
246    
247     =item connect = ondemand|never|always|disabled
248    
249     Sets the connect mode (default: C<always>). It can be C<always> (always
250     try to establish and keep a conenction to the given host), C<never>
251     (nevr initiate a connection to the given host, but accept connections),
252     C<ondemand> (try to establish a connection on the first packet sent, and
253     take it down after the keepalive interval) or C<disabled> (node is bad,
254     don't talk to it).
255    
256     =item inherit-tos = yes|no
257    
258     Wether to inherit the TOS settings of packets sent to the tunnel when
259     sending packets to this node (default: C<yes>). If set to C<yes> then
260     outgoing tunnel packets will have the same TOS setting as the packets sent
261     to the tunnel device, which is usually what you want.
262    
263     =item compress = yes|no
264    
265     Wether to compress data packets sent to this host (default: C<yes>,
266     compression is really cheap even on slow computers and has no size
267     overhead at all).
268    
269     =back
270    
271     =head1 CONFIG DIRECTORY LAYOUT
272    
273     The default (or recommended) directory layout for the config directory is:
274    
275     =over 4
276    
277     =item vped.conf
278    
279     The config file.
280    
281     =item if-up
282    
283     The if-up script
284    
285     =item node-up, node-down
286    
287     If used the node up or node-down scripts.
288    
289     =item hostkey
290    
291     The private key (taken from C<hostkeys/nodename>) of the current host.
292    
293     =item pubkey/nodename
294    
295     The public keys of the other nodes, one file per node.
296    
297     =back
298    
299     =head1 SEE ALSO
300    
301     vpe(8), vped(8), vpectrl(8).
302    
303     =head1 AUTHOR
304    
305     Marc Lehmann <vpe@plan9.de>
306