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Revision: 1.4
Committed: Mon Apr 7 01:12:56 2003 UTC (21 years, 1 month ago) by pcg
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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 if-up = relative-or-absolute-path
140    
141     Sets the path of a script that should be called immediately after the
142     network interface is initialized (but not neccessarily up). The following
143     environment variables are passed to it (the values are just examples):
144    
145     =over 4
146    
147     =item CONFBASE=/etc/vpe
148    
149     The configuration base directory.
150    
151     =item IFNAME=vpn0
152    
153     The interface to initialize.
154    
155     =item MTU=1436
156    
157     The MTU to set the interface to. You can use lower values (if done
158     consistently on all hosts), but this is usually ineffective.
159    
160     =item MAC=fe:fd:80:00:00:01
161    
162     The MAC address to set the interface to. The script *must* set the
163     interface MAC to this value. On GNU/Linux you will most likely use this:
164    
165     ip link set $IFNAME address $MAC mtu $MTU up
166    
167     =item NODENAME=branch1
168    
169     The nickname of the current node, as passed to the vped daemon.
170    
171     =item NODEID=1
172    
173     The numerical node id of the current node. The first node mentioned in the
174     config file gets ID 1, the second ID 2 and so on.
175    
176     =back
177    
178     Here is a simple if-up script:
179    
180     #!/bin/sh
181     ip link set $IFNAME address $MAC mtu $MTU up
182     [ $NODENAME = branch1 ] && ip addr add 10.0.0.1 dev $IFNAME
183     [ $NODENAME = branch2 ] && ip addr add 10.1.0.1 dev $IFNAME
184     ip route add 10.0.0.0/8 dev $IFNAME
185    
186     More complicated examples (using routing to reduce arp traffic) can be
187     found in the etc/ subdirectory of the distribution.
188    
189     =item node-up = relative-or-absolute-path
190    
191     Sets a command (default: no script) that should be called whenever a
192     connection is established (even on rekeying operations). In addition
193     to the variables passed to C<if-up> scripts, the following environment
194     variables will be set:
195    
196     =over 4
197    
198     =item DESTNODE=branch2
199    
200     The name of the remote node.
201    
202     =item DESTID=2
203    
204     The node id of the remote node.
205    
206     =item DESTIP=188.13.66.8
207    
208     The numerical IP address of the remote host (vped accepts connections from
209     everywhere, as long as the other host can authenticate itself).
210    
211     =item DESTPORT=407 # deprecated
212    
213     The UDP port used by the other side.
214    
215     =item STATE=UP
216    
217     Node-up scripts get called with STATE=UP, node-down scripts get called
218     with STATE=DOWN.
219    
220     =back
221    
222     Here is a nontrivial example that uses nsupdate to update the name => ip
223     mapping in some dns zone:
224    
225     #!/bin/sh
226     {
227     echo update delete $DESTNODE.lowttl.example.net. a
228     echo update add $DESTNODE.lowttl.example.net. 1 in a $DESTIP
229     echo
230     } | nsupdate -d -k $CONFBASE:key.example.net.
231    
232     =item node-down = relative-or-absolute-path
233    
234     Same as C<node-up>, but gets called whenever a connection is lost.
235    
236 pcg 1.4 =item http-proxy-host = hostname/ip
237    
238     The C<http-proxy>-family of options are only available if vpe was
239     compiled with the C<--enable-http-proxy> option and enable tunneling of
240     tcp connections through a http proxy server.
241    
242     C<http-proxy-host> and C<http-proxy-port> should specify the hostname and
243     port number of the proxy server. See C<http-proxy-loginpw> if your proxy
244     requires authentication.
245    
246     Please note that vpe will still try to resolve all hostnames in the
247     configuration file, so if you are behind a proxy without access to a dns
248     server better use numerical IP addresses.
249    
250     To make best use of this option disable all protocols except tcp in your
251     config file and make sure your routers (or all other hosts) are listening
252     on a port that the proxy allows (443, https, is a common choice).
253    
254     If you have a router, connecting to it will suffice. Otherwise tcp must be
255     enabled on all hosts.
256    
257     Example:
258    
259     http-proxy-host = proxy.example.com
260     http-proxy-port = 3128 # 8080 is another common choice
261     http-proxy-auth = schmorp:grumbeere
262    
263     =item http-proxy-port = proxy-tcp-port
264    
265     The port where your proxy server listens.
266    
267     =item http-proxy-auth = login:password
268    
269     The optional login and password used to authenticate to the proxy server,
270     seperated by a literal colon (C<:>). Only basic authentication is
271     currently supported.
272    
273 pcg 1.1 =back
274    
275     =head2 NODE SPECIFIC SETTINGS
276    
277     The following settings are node-specific, that is, every node can have
278     different settings, even within the same vped instance. Settings that are
279     executed before the first node section set the defaults, settings that are
280     executed within a node section only apply to the given node.
281    
282     =over 4
283    
284     =item udp-port = port-number
285    
286     Sets the port number used by the UDP protocol (default: C<407>, not
287     officially assigned by IANA!).
288 pcg 1.3
289     =item tcp-port = port-number
290    
291     Similar to C<udp-port> (default: C<407>), but sets the TCP port number.
292    
293     =item enable-rawip = yes|true|on | no|false|off
294    
295     Enable the RAW IPv4 transport using the C<ip-proto> protocol
296     (default: C<no>). This is the best choice, since the overhead per packet
297     is only 38 bytes, as opposed to UDP's 58 (or TCP's 60+).
298    
299     =item enable-udp = yes|true|on | no|false|off
300    
301     Enable the UDPv4 transport using the C<udp-port> port
302     (default: C<yes>). This is a good general choice since UDP tunnels well
303     through many firewalls.
304    
305     =item enable-tcp = yes|true|on | no|false|off
306    
307     Enable the TCPv4 transport using the C<tcp-port> port
308     (default: C<no>). Support for this horribly unsuitable protocol is only
309     available when vpe was compiled using the C<--enable-tcp> option. Never
310     use this transport unless you really must, it is horribly ineffiecent and
311     resource-intensive compared to the other transports.
312 pcg 1.1
313     =item router-priority = positive-number
314    
315     Sets the router priority of the given host (default: C<0>, disabled). If
316     some host tries to connect to another host without a hostname, it asks
317     the router host for it's IP address. The router host is the one with the
318     highest priority that is currently reachable. Make sure all clients always
319     connect to the router hosts, otherwise conencting to them is impossible.
320    
321     =item connect = ondemand|never|always|disabled
322    
323     Sets the connect mode (default: C<always>). It can be C<always> (always
324     try to establish and keep a conenction to the given host), C<never>
325     (nevr initiate a connection to the given host, but accept connections),
326     C<ondemand> (try to establish a connection on the first packet sent, and
327     take it down after the keepalive interval) or C<disabled> (node is bad,
328     don't talk to it).
329    
330     =item inherit-tos = yes|true|on | no|false|off
331    
332     Wether to inherit the TOS settings of packets sent to the tunnel when
333     sending packets to this node (default: C<yes>). If set to C<yes> then
334     outgoing tunnel packets will have the same TOS setting as the packets sent
335     to the tunnel device, which is usually what you want.
336    
337     =item compress = yes|true|on | no|false|off
338    
339     Wether to compress data packets sent to this host (default: C<yes>).
340     Compression is really cheap even on slow computers and has no size
341     overhead at all, so enabling this is a good idea.
342    
343     =back
344    
345     =head1 CONFIG DIRECTORY LAYOUT
346    
347     The default (or recommended) directory layout for the config directory is:
348    
349     =over 4
350    
351     =item vped.conf
352    
353     The config file.
354    
355     =item if-up
356    
357     The if-up script
358    
359     =item node-up, node-down
360    
361     If used the node up or node-down scripts.
362    
363     =item hostkey
364    
365     The private key (taken from C<hostkeys/nodename>) of the current host.
366    
367     =item pubkey/nodename
368    
369     The public keys of the other nodes, one file per node.
370    
371     =back
372    
373     =head1 SEE ALSO
374    
375     vpe(5), vped(8), vpectrl(8).
376    
377     =head1 AUTHOR
378    
379     Marc Lehmann <vpe@plan9.de>
380