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Revision: 1.28
Committed: Sun Mar 6 13:49:49 2011 UTC (13 years, 2 months ago) by root
Branch: MAIN
Changes since 1.27: +32 -31 lines
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# Content
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131 .IX Title "GVPE.CONF 5"
132 .TH GVPE.CONF 5 "2011-02-15" "2.24" "GNU Virtual Private Ethernet"
133 .SH "NAME"
134 gvpe.conf \- configuration file for the GNU VPE daemon
135 .SH "SYNOPSIS"
136 .IX Header "SYNOPSIS"
137 .Vb 4
138 \& # global options for all nodes
139 \& udp\-port = 407
140 \& mtu = 1492
141 \& ifname = vpn0
142 .Ve
143 .PP
144 .Vb 3
145 \& # first node is named branch1 and is at 1.2.3.4
146 \& node = branch1
147 \& hostname = 1.2.3.4
148 .Ve
149 .PP
150 .Vb 4
151 \& # second node uses dns to resolve the address
152 \& node = branch2
153 \& hostname = www.example.net
154 \& udp\-port = 500 # this host uses a different udp\-port
155 .Ve
156 .PP
157 .Vb 3
158 \& # third node has no fixed ip address
159 \& node = branch3
160 \& connect = ondemand
161 .Ve
162 .SH "DESCRIPTION"
163 .IX Header "DESCRIPTION"
164 The gvpe config file consists of a series of lines that contain \f(CW\*(C`variable
165 = value\*(C'\fR pairs. Empty lines are ignored. Comments start with a \f(CW\*(C`#\*(C'\fR and
166 extend to the end of the line. They can be used on their own lines, or
167 after any directives. Whitespace is allowed around the \f(CW\*(C`=\*(C'\fR sign or after
168 values, but not within the variable names or values themselves.
169 .PP
170 The only exception to the above is the \*(L"on\*(R" directive that can prefix any
171 \&\f(CW\*(C`name = value\*(C'\fR setting and will only \*(L"execute\*(R" it on the named node, or
172 (if the nodename starts with \*(L"!\*(R") on all nodes except the named one.
173 .PP
174 For example, set the \s-1MTU\s0 to \f(CW1450\fR everywhere, loglevel to \f(CW\*(C`noise\*(C'\fR on
175 branch1, and connect to \f(CW\*(C`ondemand\*(C'\fR everywhere but on branch2:
176 .PP
177 .Vb 3
178 \& mtu = 1450
179 \& on branch1 loglevel = noise
180 \& on !branch2 connect = ondemand
181 .Ve
182 .PP
183 All settings are applied \*(L"in order\*(R", that is, later settings of the same
184 variable overwrite earlier ones.
185 .SH "ANATOMY OF A CONFIG FILE"
186 .IX Header "ANATOMY OF A CONFIG FILE"
187 Usually, a config file starts with a few global settings (like the \s-1UDP\s0
188 port to listen on), followed by node-specific sections that begin with a
189 \&\f(CW\*(C`node = nickname\*(C'\fR line.
190 .PP
191 Every node that is part of the network must have a section that starts
192 with \f(CW\*(C`node = nickname\*(C'\fR. The number and order of the nodes is important
193 and must be the same on all nodes. It is not uncommon for node sections to
194 be completely empty \- if the default values are right.
195 .PP
196 Node-specific settings can be used at any time. If used before the first
197 node section they will set the default values for all following nodes.
198 .SH "CONFIG VARIABLES"
199 .IX Header "CONFIG VARIABLES"
200 .Sh "\s-1GLOBAL\s0 \s-1SETTINGS\s0"
201 .IX Subsection "GLOBAL SETTINGS"
202 Global settings will affect the behaviour of the running gvpe daemon, that
203 is, they are in some sense node-specific (config files can set different
204 values on different nodes using \f(CW\*(C`on\*(C'\fR), but will affect the behaviour of
205 the gvpe daemon and all connections it creates.
206 .IP "dns-forw-host = hostname/ip" 4
207 .IX Item "dns-forw-host = hostname/ip"
208 The \s-1DNS\s0 server to forward \s-1DNS\s0 requests to for the \s-1DNS\s0 tunnel protocol
209 (default: \f(CW127.0.0.1\fR, changing it is highly recommended).
210 .IP "dns-forw-port = port-number" 4
211 .IX Item "dns-forw-port = port-number"
212 The port where the \f(CW\*(C`dns\-forw\-host\*(C'\fR is to be contacted (default: \f(CW53\fR,
213 which is fine in most cases).
214 .IP "dns-max-outstanding = integer-number-of-requests" 4
215 .IX Item "dns-max-outstanding = integer-number-of-requests"
216 The maximum number of outstanding \s-1DNS\s0 transport requests
217 (default: \f(CW100\fR). \s-1GVPE\s0 will never issue more requests then the given
218 limit without receiving replies. In heavily overloaded situations it might
219 help to set this to a low number (e.g. \f(CW3\fR or even \f(CW1\fR) to limit the
220 number of parallel requests.
221 .Sp
222 The default should be working \s-1OK\s0 for most links.
223 .IP "dns-overlap-factor = float" 4
224 .IX Item "dns-overlap-factor = float"
225 The \s-1DNS\s0 transport uses the minimum request latency (\fBmin_latency\fR) seen
226 during a connection as it's timing base. This factor (default: \f(CW0.5\fR,
227 must be > 0) is multiplied by \fBmin_latency\fR to get the maximum sending
228 rate (= minimum send interval), i.e. a factor of \f(CW1\fR means that a new
229 request might be generated every \fBmin_latency\fR seconds, which means on
230 average there should only ever be one outstanding request. A factor of
231 \&\f(CW0.5\fR means that \s-1GVPE\s0 will send requests twice as often as the minimum
232 latency measured.
233 .Sp
234 For congested or picky \s-1DNS\s0 forwarders you could use a value nearer to or
235 exceeding \f(CW1\fR.
236 .Sp
237 The default should be working \s-1OK\s0 for most links.
238 .IP "dns-send-interval = send-interval-in-seconds" 4
239 .IX Item "dns-send-interval = send-interval-in-seconds"
240 The minimum send interval (= maximum rate) that the \s-1DNS\s0 transport will
241 use to send new \s-1DNS\s0 requests. \s-1GVPE\s0 will not exceed this rate even when
242 the latency is very low. The default is \f(CW0.01\fR, which means \s-1GVPE\s0 will
243 not send more than 100 \s-1DNS\s0 requests per connection per second. For
244 high-bandwidth links you could go lower, e.g. to \f(CW0.001\fR or so. For
245 congested or rate-limited links, you might want to go higher, say \f(CW0.1\fR,
246 \&\f(CW0.2\fR or even higher.
247 .Sp
248 The default should be working \s-1OK\s0 for most links.
249 .IP "dns-timeout-factor = float" 4
250 .IX Item "dns-timeout-factor = float"
251 Factor to multiply the \f(CW\*(C`min_latency\*(C'\fR (see \f(CW\*(C`dns\-overlap\-factor\*(C'\fR) by to
252 get request timeouts. The default of \f(CW8\fR means that the \s-1DNS\s0 transport
253 will resend the request when no reply has been received for longer than
254 eight times the minimum (= expected) latency, assuming the request or
255 reply has been lost.
256 .Sp
257 For congested links a higher value might be necessary (e.g. \f(CW30\fR). If
258 the link is very stable lower values (e.g. \f(CW2\fR) might work
259 nicely. Values near or below \f(CW1\fR makes no sense whatsoever.
260 .Sp
261 The default should be working \s-1OK\s0 for most links but will result in low
262 throughput if packet loss is high.
263 .IP "if-up = relative-or-absolute-path" 4
264 .IX Item "if-up = relative-or-absolute-path"
265 Sets the path of a script that should be called immediately after the
266 network interface is initialized (but not necessarily up). The following
267 environment variables are passed to it (the values are just examples).
268 .Sp
269 Variables that have the same value on all nodes:
270 .RS 4
271 .IP "CONFBASE=/etc/gvpe" 4
272 .IX Item "CONFBASE=/etc/gvpe"
273 The configuration base directory.
274 .IP "IFNAME=vpn0" 4
275 .IX Item "IFNAME=vpn0"
276 The network interface to initialize.
277 .IP "IFTYPE=native # or tincd" 4
278 .IX Item "IFTYPE=native # or tincd"
279 .PD 0
280 .IP "IFSUBTYPE=linux # or freebsd, darwin etc.." 4
281 .IX Item "IFSUBTYPE=linux # or freebsd, darwin etc.."
282 .PD
283 The interface type (\f(CW\*(C`native\*(C'\fR or \f(CW\*(C`tincd\*(C'\fR) and the subtype (usually the
284 \&\s-1OS\s0 name in lowercase) that this \s-1GVPE\s0 was configured for. Can be used to
285 select the correct syntax to use for network-related commands.
286 .IP "MTU=1436" 4
287 .IX Item "MTU=1436"
288 The \s-1MTU\s0 to set the interface to. You can use lower values (if done
289 consistently on all nodes), but this is usually either inefficient or
290 simply ineffective.
291 .IP "NODES=5" 4
292 .IX Item "NODES=5"
293 The number of nodes in this \s-1GVPE\s0 network.
294 .RE
295 .RS 4
296 .Sp
297 Variables that are node-specific and with values pertaining to the node
298 running this \s-1GVPE:\s0
299 .IP "IFUPDATA=string" 4
300 .IX Item "IFUPDATA=string"
301 The value of the configuration directive \f(CW\*(C`if\-up\-data\*(C'\fR.
302 .IP "MAC=fe:fd:80:00:00:01" 4
303 .IX Item "MAC=fe:fd:80:00:00:01"
304 The \s-1MAC\s0 address the network interface has to use.
305 .Sp
306 Might be used to initialize interfaces on platforms where \s-1GVPE\s0 does not
307 do this automatically. Please see the \f(CW\*(C`gvpe.osdep(5)\*(C'\fR man page for
308 platform-specific information.
309 .IP "NODENAME=branch1" 4
310 .IX Item "NODENAME=branch1"
311 The nickname of the node.
312 .IP "NODEID=1" 4
313 .IX Item "NODEID=1"
314 The numerical node \s-1ID\s0 of the node running this instance of \s-1GVPE\s0. The first
315 node mentioned in the config file gets \s-1ID\s0 1, the second \s-1ID\s0 2 and so on.
316 .RE
317 .RS 4
318 .Sp
319 In addition, all node-specific variables (except \f(CW\*(C`NODEID\*(C'\fR) will be
320 available with a postfix of \f(CW\*(C`_nodeid\*(C'\fR, which contains the value for that
321 node, e.g. the \f(CW\*(C`MAC_1\*(C'\fR variable contains the \s-1MAC\s0 address of node #1, while
322 the \f(CW\*(C`NODENAME_22\*(C'\fR variable contains the name of node #22.
323 .Sp
324 Here is a simple if-up script:
325 .Sp
326 .Vb 5
327 \& #!/bin/sh
328 \& ip link set $IFNAME up
329 \& [ $NODENAME = branch1 ] && ip addr add 10.0.0.1 dev $IFNAME
330 \& [ $NODENAME = branch2 ] && ip addr add 10.1.0.1 dev $IFNAME
331 \& ip route add 10.0.0.0/8 dev $IFNAME
332 .Ve
333 .Sp
334 More complicated examples (using routing to reduce \s-1ARP\s0 traffic) can be
335 found in the \fIetc/\fR subdirectory of the distribution.
336 .RE
337 .IP "ifname = devname" 4
338 .IX Item "ifname = devname"
339 Sets the tun interface name to the given name. The default is OS-specific
340 and most probably something like \f(CW\*(C`tun0\*(C'\fR.
341 .IP "ifpersist = yes|true|on | no|false|off" 4
342 .IX Item "ifpersist = yes|true|on | no|false|off"
343 Should the tun/tap device be made persistent, that is, should the device
344 stay up even when gvpe exits? Some versions of the tunnel device have
345 problems sending packets when gvpe is restarted in persistent mode, so
346 if the connections can be established but you cannot send packets from
347 the local node, try to set this to \f(CW\*(C`off\*(C'\fR and do an ifconfig down on the
348 device.
349 .IP "ip-proto = numerical-ip-protocol" 4
350 .IX Item "ip-proto = numerical-ip-protocol"
351 Sets the protocol number to be used for the rawip protocol. This is a
352 global option because all nodes must use the same protocol, and since
353 there are no port numbers, you cannot easily run more than one gvpe
354 instance using the same protocol, nor can you share the protocol with
355 other programs.
356 .Sp
357 The default is 47 (\s-1GRE\s0), which has a good chance of tunneling
358 through firewalls (but note that gvpe's rawip protocol is not \s-1GRE\s0
359 compatible). Other common choices are 50 (\s-1IPSEC\s0, \s-1ESP\s0), 51 (\s-1IPSEC\s0, \s-1AH\s0), 4
360 (\s-1IPIP\s0 tunnels) or 98 (\s-1ENCAP\s0, rfc1241).
361 .Sp
362 Many versions of Linux seem to have a bug that causes them to reorder
363 packets for some ip protocols (\s-1GRE\s0, \s-1ESP\s0) but not for others (\s-1AH\s0), so
364 choose wisely (that is, use 51, \s-1AH\s0).
365 .IP "http-proxy-host = hostname/ip" 4
366 .IX Item "http-proxy-host = hostname/ip"
367 The \f(CW\*(C`http\-proxy\-*\*(C'\fR family of options are only available if gvpe was
368 compiled with the \f(CW\*(C`\-\-enable\-http\-proxy\*(C'\fR option and enable tunneling of
369 tcp connections through a http proxy server.
370 .Sp
371 \&\f(CW\*(C`http\-proxy\-host\*(C'\fR and \f(CW\*(C`http\-proxy\-port\*(C'\fR should specify the hostname and
372 port number of the proxy server. See \f(CW\*(C`http\-proxy\-loginpw\*(C'\fR if your proxy
373 requires authentication.
374 .Sp
375 Please note that gvpe will still try to resolve all hostnames in the
376 configuration file, so if you are behind a proxy without access to a \s-1DNS\s0
377 server better use numerical \s-1IP\s0 addresses.
378 .Sp
379 To make best use of this option disable all protocols except \s-1TCP\s0 in your
380 config file and make sure your routers (or all other nodes) are listening
381 on a port that the proxy allows (443, https, is a common choice).
382 .Sp
383 If you have a router, connecting to it will suffice. Otherwise \s-1TCP\s0 must be
384 enabled on all nodes.
385 .Sp
386 Example:
387 .Sp
388 .Vb 3
389 \& http\-proxy\-host = proxy.example.com
390 \& http\-proxy\-port = 3128 # 8080 is another common choice
391 \& http\-proxy\-auth = schmorp:grumbeere
392 .Ve
393 .IP "http-proxy-port = proxy-tcp-port" 4
394 .IX Item "http-proxy-port = proxy-tcp-port"
395 The port where your proxy server listens.
396 .IP "http-proxy-auth = login:password" 4
397 .IX Item "http-proxy-auth = login:password"
398 The optional login and password used to authenticate to the proxy server,
399 separated by a literal colon (\f(CW\*(C`:\*(C'\fR). Only basic authentication is
400 currently supported.
401 .IP "keepalive = seconds" 4
402 .IX Item "keepalive = seconds"
403 Sets the keepalive probe interval in seconds (default: \f(CW60\fR). After this
404 many seconds of inactivity the daemon will start to send keepalive probe
405 every 3 seconds until it receives a reply from the other end. If no reply
406 is received within 15 seconds, the peer is considered unreachable and the
407 connection is closed.
408 .IP "loglevel = noise|trace|debug|info|notice|warn|error|critical" 4
409 .IX Item "loglevel = noise|trace|debug|info|notice|warn|error|critical"
410 Set the logging level. Connection established messages are logged at level
411 \&\f(CW\*(C`info\*(C'\fR, notable errors are logged with \f(CW\*(C`error\*(C'\fR. Default is \f(CW\*(C`info\*(C'\fR.
412 .IP "mtu = bytes" 4
413 .IX Item "mtu = bytes"
414 Sets the maximum \s-1MTU\s0 that should be used on outgoing packets (basically
415 the \s-1MTU\s0 of the outgoing interface) The daemon will automatically calculate
416 maximum overhead (e.g. \s-1UDP\s0 header size, encryption blocksize...) and pass
417 this information to the \f(CW\*(C`if\-up\*(C'\fR script.
418 .Sp
419 Recommended values are 1500 (ethernet), 1492 (pppoe), 1472 (pptp).
420 .Sp
421 This value must be the minimum of the \s-1MTU\s0 values of all nodes.
422 .IP "node = nickname" 4
423 .IX Item "node = nickname"
424 Not really a config setting but introduces a node section. The nickname is
425 used to select the right configuration section and must be passed as an
426 argument to the gvpe daemon.
427 .IP "node-up = relative-or-absolute-path" 4
428 .IX Item "node-up = relative-or-absolute-path"
429 Sets a command (default: none) that should be called whenever a connection
430 is established (even on rekeying operations). Note that node\-up/down
431 scripts will be run asynchronously, but execution is serialised, so there
432 will only ever be one such script running.
433 .Sp
434 In addition to all the variables passed to \f(CW\*(C`if\-up\*(C'\fR scripts, the following
435 environment variables will be set (values are just examples):
436 .RS 4
437 .IP "DESTNODE=branch2" 4
438 .IX Item "DESTNODE=branch2"
439 The name of the remote node.
440 .IP "DESTID=2" 4
441 .IX Item "DESTID=2"
442 The node id of the remote node.
443 .IP "DESTSI=rawip/88.99.77.55:0" 4
444 .IX Item "DESTSI=rawip/88.99.77.55:0"
445 The \*(L"socket info\*(R" of the target node, protocol dependent but usually in
446 the format protocol/ip:port.
447 .IP "DESTIP=188.13.66.8" 4
448 .IX Item "DESTIP=188.13.66.8"
449 The numerical \s-1IP\s0 address of the remote node (gvpe accepts connections from
450 everywhere, as long as the other node can authenticate itself).
451 .IP "DESTPORT=655 # deprecated" 4
452 .IX Item "DESTPORT=655 # deprecated"
453 The protocol port used by the other side, if applicable.
454 .IP "STATE=up" 4
455 .IX Item "STATE=up"
456 Node-up scripts get called with STATE=up, node-change scripts get called
457 with STATE=change and node-down scripts get called with STATE=down.
458 .RE
459 .RS 4
460 .Sp
461 Here is a nontrivial example that uses nsupdate to update the name => ip
462 mapping in some \s-1DNS\s0 zone:
463 .Sp
464 .Vb 6
465 \& #!/bin/sh
466 \& {
467 \& echo update delete $DESTNODE.lowttl.example.net. a
468 \& echo update add $DESTNODE.lowttl.example.net. 1 in a $DESTIP
469 \& echo
470 \& } | nsupdate \-d \-k $CONFBASE:key.example.net.
471 .Ve
472 .RE
473 .IP "node-change = relative-or-absolute-path" 4
474 .IX Item "node-change = relative-or-absolute-path"
475 Same as \f(CW\*(C`node\-change\*(C'\fR, but gets called whenever something about a
476 connection changes (such as the source \s-1IP\s0 address).
477 .IP "node-down = relative-or-absolute-path" 4
478 .IX Item "node-down = relative-or-absolute-path"
479 Same as \f(CW\*(C`node\-up\*(C'\fR, but gets called whenever a connection is lost.
480 .IP "pid-file = path" 4
481 .IX Item "pid-file = path"
482 The path to the pid file to check and create
483 (default: \f(CW\*(C`LOCALSTATEDIR/run/gvpe.pid\*(C'\fR).
484 .IP "private-key = relative-path-to-key" 4
485 .IX Item "private-key = relative-path-to-key"
486 Sets the path (relative to the config directory) to the private key
487 (default: \f(CW\*(C`hostkey\*(C'\fR). This is a printf format string so every \f(CW\*(C`%\*(C'\fR must
488 be doubled. A single \f(CW%s\fR is replaced by the hostname, so you could
489 use paths like \f(CW\*(C`hostkeys/%s\*(C'\fR to fetch the files at the location where
490 \&\f(CW\*(C`gvpectrl\*(C'\fR puts them.
491 .Sp
492 Since only the private key file of the current node is used and the
493 private key file should be kept secret per-node to avoid spoofing, it is
494 not recommended to use this feature.
495 .IP "rekey = seconds" 4
496 .IX Item "rekey = seconds"
497 Sets the rekeying interval in seconds (default: \f(CW3600\fR). Connections are
498 reestablished every \f(CW\*(C`rekey\*(C'\fR seconds, making them use a new encryption
499 key.
500 .IP "nfmark = integer" 4
501 .IX Item "nfmark = integer"
502 This advanced option, when set to a nonzero value (default: \f(CW0\fR), tries
503 to set the netfilter mark (or fwmark) value on all sockets gvpe uses to
504 send packets.
505 .Sp
506 This can be used to make gvpe use a different set of routing rules. For
507 example, on GNU/Linux, the \f(CW\*(C`if\-up\*(C'\fR could set \f(CW\*(C`nfmark\*(C'\fR to 1000 and then
508 put all routing rules into table \f(CW99\fR and then use an ip rule to make
509 gvpe traffic avoid that routing table, in effect routing normal traffic
510 via gvpe and gvpe traffic via the normal system routing tables:
511 .Sp
512 .Vb 1
513 \& ip rule add not fwmark 1000 lookup 99
514 .Ve
515 .Sh "\s-1NODE\s0 \s-1SPECIFIC\s0 \s-1SETTINGS\s0"
516 .IX Subsection "NODE SPECIFIC SETTINGS"
517 The following settings are node\-specific, that is, every node can have
518 different settings, even within the same gvpe instance. Settings that are
519 set before the first node section set the defaults, settings that are
520 set within a node section only apply to the given node.
521 .IP "allow-direct = nodename" 4
522 .IX Item "allow-direct = nodename"
523 Allow direct connections to this node. See \f(CW\*(C`deny\-direct\*(C'\fR for more info.
524 .IP "compress = yes|true|on | no|false|off" 4
525 .IX Item "compress = yes|true|on | no|false|off"
526 For the current node, this specified whether it will accept compressed
527 packets, and for all other nodes, this specifies whether to try to
528 compress data packets sent to this node (default: \f(CW\*(C`yes\*(C'\fR). Compression is
529 really cheap even on slow computers, has no size overhead at all and will
530 only be used when the other side supports compression, so enabling this is
531 often a good idea.
532 .IP "connect = ondemand | never | always | disabled" 4
533 .IX Item "connect = ondemand | never | always | disabled"
534 Sets the connect mode (default: \f(CW\*(C`always\*(C'\fR). It can be \f(CW\*(C`always\*(C'\fR (always
535 try to establish and keep a connection to the given node), \f(CW\*(C`never\*(C'\fR
536 (never initiate a connection to the given host, but accept connections),
537 \&\f(CW\*(C`ondemand\*(C'\fR (try to establish a connection when there are outstanding
538 packets in the queue and take it down after the keepalive interval) or
539 \&\f(CW\*(C`disabled\*(C'\fR (node is bad, don't talk to it).
540 .Sp
541 Routers will automatically be forced to \f(CW\*(C`always\*(C'\fR unless they are
542 \&\f(CW\*(C`disabled\*(C'\fR, to ensure all nodes can talk to each other.
543 .IP "deny-direct = nodename | *" 4
544 .IX Item "deny-direct = nodename | *"
545 Deny direct connections to the specified node (or all nodes when \f(CW\*(C`*\*(C'\fR
546 is given). Only one node can be specified, but you can use multiple
547 \&\f(CW\*(C`allow\-direct\*(C'\fR and \f(CW\*(C`deny\-direct\*(C'\fR statements. This only makes sense in
548 networks with routers, as routers are required for indirect connections.
549 .Sp
550 Sometimes, a node cannot reach some other nodes for reasons of network
551 connectivity. For example, a node behind a firewall that only allows
552 connections to/from a single other node in the network. In this case one
553 should specify \f(CW\*(C`deny\-direct = *\*(C'\fR and \f(CW\*(C`allow\-direct = othernodename\*(C'\fR (the other
554 node \fImust\fR be a router for this to work).
555 .Sp
556 The algorithm to check whether a connection may be direct is as follows:
557 .Sp
558 1. Other node mentioned in an \f(CW\*(C`allow\-direct\*(C'\fR? If yes, allow the connection.
559 .Sp
560 2. Other node mentioned in a \f(CW\*(C`deny\-direct\*(C'\fR? If yes, deny direct connections.
561 .Sp
562 3. Allow the connection.
563 .Sp
564 That is, \f(CW\*(C`allow\-direct\*(C'\fR takes precedence over \f(CW\*(C`deny\-direct\*(C'\fR.
565 .Sp
566 The check is done in both directions, i.e. both nodes must allow a direct
567 connection before one is attempted, so you only need to specify connect
568 limitations on one node.
569 .IP "dns-domain = domain-suffix" 4
570 .IX Item "dns-domain = domain-suffix"
571 The \s-1DNS\s0 domain suffix that points to the \s-1DNS\s0 tunnel server for this node.
572 .Sp
573 The domain must point to a \s-1NS\s0 record that points to the \fIdns-hostname\fR,
574 i.e.
575 .Sp
576 .Vb 2
577 \& dns\-domainname = tunnel.example.net
578 \& dns\-hostname = tunnel\-server.example.net
579 .Ve
580 .Sp
581 Corresponds to the following \s-1DNS\s0 entries in the \f(CW\*(C`example.net\*(C'\fR domain:
582 .Sp
583 .Vb 2
584 \& tunnel.example.net. NS tunnel\-server.example.net.
585 \& tunnel\-server.example.net. A 13.13.13.13
586 .Ve
587 .IP "dns-hostname = hostname/ip" 4
588 .IX Item "dns-hostname = hostname/ip"
589 The address to bind the \s-1DNS\s0 tunnel socket to, similar to the \f(CW\*(C`hostname\*(C'\fR,
590 but for the \s-1DNS\s0 tunnel protocol only. Default: \f(CW0.0.0.0\fR, but that might
591 change.
592 .IP "dns-port = port-number" 4
593 .IX Item "dns-port = port-number"
594 The port to bind the \s-1DNS\s0 tunnel socket to. Must be \f(CW53\fR on \s-1DNS\s0 tunnel servers.
595 .IP "enable-dns = yes|true|on | no|false|off" 4
596 .IX Item "enable-dns = yes|true|on | no|false|off"
597 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1DNS\s0 transport
598 protocol. Avoid this protocol if you can.
599 .Sp
600 Enable the \s-1DNS\s0 tunneling protocol on this node, either as server or as
601 client. Support for this transport protocol is only available when gvpe
602 was compiled using the \f(CW\*(C`\-\-enable\-dns\*(C'\fR option.
603 .IP "enable-icmp = yes|true|on | no|false|off" 4
604 .IX Item "enable-icmp = yes|true|on | no|false|off"
605 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1ICMP\s0 transport protocol.
606 .Sp
607 Enable the \s-1ICMP\s0 transport using \s-1ICMP\s0 packets of type \f(CW\*(C`icmp\-type\*(C'\fR on this
608 node.
609 .IP "enable-rawip = yes|true|on | no|false|off" 4
610 .IX Item "enable-rawip = yes|true|on | no|false|off"
611 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1RAW\s0 \s-1IP\s0 transport protocol.
612 .Sp
613 Enable the \s-1RAW\s0 IPv4 transport using the \f(CW\*(C`ip\-proto\*(C'\fR protocol
614 (default: \f(CW\*(C`no\*(C'\fR).
615 .IP "enable-tcp = yes|true|on | no|false|off" 4
616 .IX Item "enable-tcp = yes|true|on | no|false|off"
617 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1TCP\s0 transport protocol.
618 .Sp
619 Enable the TCPv4 transport using the \f(CW\*(C`tcp\-port\*(C'\fR port
620 (default: \f(CW\*(C`no\*(C'\fR). Support for this transport protocol is only available
621 when gvpe was compiled using the \f(CW\*(C`\-\-enable\-tcp\*(C'\fR option.
622 .IP "enable-udp = yes|true|on | no|false|off" 4
623 .IX Item "enable-udp = yes|true|on | no|false|off"
624 See \fIgvpe.protocol\fR\|(7) for a description of the \s-1UDP\s0 transport protocol.
625 .Sp
626 Enable the UDPv4 transport using the \f(CW\*(C`udp\-port\*(C'\fR port (default: \f(CW\*(C`no\*(C'\fR).
627 .IP "hostname = hostname | ip [can not be defaulted]" 4
628 .IX Item "hostname = hostname | ip [can not be defaulted]"
629 Forces the address of this node to be set to the given \s-1DNS\s0 hostname or \s-1IP\s0
630 address. It will be resolved before each connect request, so dyndns should
631 work fine. If this setting is not specified and a router is available,
632 then the router will be queried for the address of this node. Otherwise,
633 the connection attempt will fail.
634 .Sp
635 Note that \s-1DNS\s0 resolving is done synchronously, pausing the daemon. If that
636 is an issue you need to specify \s-1IP\s0 addresses.
637 .IP "icmp-type = integer" 4
638 .IX Item "icmp-type = integer"
639 Sets the type value to be used for outgoing (and incoming) packets sent
640 via the \s-1ICMP\s0 transport.
641 .Sp
642 The default is \f(CW0\fR (which is \f(CW\*(C`echo\-reply\*(C'\fR, also known as
643 \&\*(L"ping\-reply\*(R"). Other useful values include \f(CW8\fR (\f(CW\*(C`echo\-request\*(C'\fR, a.k.a.
644 \&\*(L"ping\*(R") and \f(CW11\fR (\f(CW\*(C`time\-exceeded\*(C'\fR), but any 8\-bit value can be used.
645 .IP "if-up-data = value" 4
646 .IX Item "if-up-data = value"
647 The value specified using this directive will be passed to the \f(CW\*(C`if\-up\*(C'\fR
648 script in the environment variable \f(CW\*(C`IFUPDATA\*(C'\fR.
649 .IP "inherit-tos = yes|true|on | no|false|off" 4
650 .IX Item "inherit-tos = yes|true|on | no|false|off"
651 Whether to inherit the \s-1TOS\s0 settings of packets sent to the tunnel when
652 sending packets to this node (default: \f(CW\*(C`yes\*(C'\fR). If set to \f(CW\*(C`yes\*(C'\fR then
653 outgoing tunnel packets will have the same \s-1TOS\s0 setting as the packets sent
654 to the tunnel device, which is usually what you want.
655 .IP "max-retry = positive-number" 4
656 .IX Item "max-retry = positive-number"
657 The maximum interval in seconds (default: \f(CW3600\fR, one hour) between
658 retries to establish a connection to this node. When a connection cannot
659 be established, gvpe uses exponential back-off capped at this value. It's
660 sometimes useful to set this to a much lower value (e.g. \f(CW120\fR) on
661 connections to routers that usually are stable but sometimes are down, to
662 assure quick reconnections even after longer downtimes.
663 .IP "max-ttl = seconds" 4
664 .IX Item "max-ttl = seconds"
665 Expire packets that couldn't be sent after this many seconds
666 (default: \f(CW60\fR). Gvpe will normally queue packets for a node without an
667 active connection, in the hope of establishing a connection soon. This
668 value specifies the maximum lifetime a packet will stay in the queue, if a
669 packet gets older, it will be thrown away.
670 .IP "max-queue = positive\-number>=1" 4
671 .IX Item "max-queue = positive-number>=1"
672 The maximum number of packets that will be queued (default: \f(CW512\fR)
673 for this node. If more packets are sent then earlier packets will be
674 expired. See \f(CW\*(C`max\-ttl\*(C'\fR, above.
675 .IP "router-priority = 0 | 1 | positive\-number>=2" 4
676 .IX Item "router-priority = 0 | 1 | positive-number>=2"
677 Sets the router priority of the given node (default: \f(CW0\fR, disabled).
678 .Sp
679 If some node tries to connect to another node but it doesn't have a
680 hostname, it asks a router node for it's \s-1IP\s0 address. The router node
681 chosen is the one with the highest priority larger than \f(CW1\fR that is
682 currently reachable. This is called a \fImediated\fR connection, as the
683 connection itself will still be direct, but it uses another node to
684 mediate between the two nodes.
685 .Sp
686 The value \f(CW0\fR disables routing, that means if the node receives a packet
687 not for itself it will not forward it but instead drop it.
688 .Sp
689 The special value \f(CW1\fR allows other hosts to route through the router
690 host, but they will never route through it by default (i.e. the config
691 file of another node needs to specify a router priority higher than one
692 to choose such a node for routing).
693 .Sp
694 The idea behind this is that some hosts can, if required, bump the
695 \&\f(CW\*(C`router\-priority\*(C'\fR setting to higher than \f(CW1\fR in their local config to
696 route through specific hosts. If \f(CW\*(C`router\-priority\*(C'\fR is \f(CW0\fR, then routing
697 will be refused, so \f(CW1\fR serves as a \*(L"enable, but do not use by default\*(R"
698 switch.
699 .Sp
700 Nodes with \f(CW\*(C`router\-priority\*(C'\fR set to \f(CW2\fR or higher will always be forced
701 to \f(CW\*(C`connect\*(C'\fR = \f(CW\*(C`always\*(C'\fR (unless they are \f(CW\*(C`disabled\*(C'\fR).
702 .IP "tcp-port = port-number" 4
703 .IX Item "tcp-port = port-number"
704 Similar to \f(CW\*(C`udp\-port\*(C'\fR (default: \f(CW655\fR), but sets the \s-1TCP\s0 port number.
705 .IP "udp-port = port-number" 4
706 .IX Item "udp-port = port-number"
707 Sets the port number used by the \s-1UDP\s0 protocol (default: \f(CW655\fR, not
708 officially assigned by \s-1IANA\s0!).
709 .SH "CONFIG DIRECTORY LAYOUT"
710 .IX Header "CONFIG DIRECTORY LAYOUT"
711 The default (or recommended) directory layout for the config directory is:
712 .IP "gvpe.conf" 4
713 .IX Item "gvpe.conf"
714 The config file.
715 .IP "if-up" 4
716 .IX Item "if-up"
717 The if-up script
718 .IP "node\-up, node-down" 4
719 .IX Item "node-up, node-down"
720 If used the node up or node-down scripts.
721 .IP "hostkey" 4
722 .IX Item "hostkey"
723 The private key (taken from \f(CW\*(C`hostkeys/nodename\*(C'\fR) of the current host.
724 .IP "pubkey/nodename" 4
725 .IX Item "pubkey/nodename"
726 The public keys of the other nodes, one file per node.
727 .SH "SEE ALSO"
728 .IX Header "SEE ALSO"
729 \&\fIgvpe\fR\|(5), \fIgvpe\fR\|(8), \fIgvpectrl\fR\|(8).
730 .SH "AUTHOR"
731 .IX Header "AUTHOR"
732 Marc Lehmann <gvpe@schmorp.de>