1 \input texinfo @c -*-texinfo-*-
8 @include tincinclude.texi
11 @dircategory Networking tools
13 * tinc: (tinc). The tinc Manual.
16 This is the info manual for @value{PACKAGE} version @value{VERSION}, a Virtual Private Network daemon.
18 Copyright @copyright{} 1998-2009 Ivo Timmermans,
19 Guus Sliepen <guus@@tinc-vpn.org> and
20 Wessel Dankers <wsl@@tinc-vpn.org>.
22 Permission is granted to make and distribute verbatim copies of this
23 manual provided the copyright notice and this permission notice are
24 preserved on all copies.
26 Permission is granted to copy and distribute modified versions of this
27 manual under the conditions for verbatim copying, provided that the
28 entire resulting derived work is distributed under the terms of a
29 permission notice identical to this one.
35 @subtitle Setting up a Virtual Private Network with tinc
36 @author Ivo Timmermans and Guus Sliepen
39 @vskip 0pt plus 1filll
41 This is the info manual for @value{PACKAGE} version @value{VERSION}, a Virtual Private Network daemon.
43 Copyright @copyright{} 1998-2009 Ivo Timmermans,
44 Guus Sliepen <guus@@tinc-vpn.org> and
45 Wessel Dankers <wsl@@tinc-vpn.org>.
47 Permission is granted to make and distribute verbatim copies of this
48 manual provided the copyright notice and this permission notice are
49 preserved on all copies.
51 Permission is granted to copy and distribute modified versions of this
52 manual under the conditions for verbatim copying, provided that the
53 entire resulting derived work is distributed under the terms of a
54 permission notice identical to this one.
59 @c ==================================================================
70 * Technical information::
71 * Platform specific information::
73 * Concept Index:: All used terms explained
77 @c ==================================================================
82 Tinc is a Virtual Private Network (VPN) daemon that uses tunneling and
83 encryption to create a secure private network between hosts on the
86 Because the tunnel appears to the IP level network code as a normal
87 network device, there is no need to adapt any existing software.
88 The encrypted tunnels allows VPN sites to share information with each other
89 over the Internet without exposing any information to others.
91 This document is the manual for tinc. Included are chapters on how to
92 configure your computer to use tinc, as well as the configuration
93 process of tinc itself.
96 * Virtual Private Networks::
98 * Supported platforms::
101 @c ==================================================================
102 @node Virtual Private Networks
103 @section Virtual Private Networks
106 A Virtual Private Network or VPN is a network that can only be accessed
107 by a few elected computers that participate. This goal is achievable in
108 more than just one way.
111 Private networks can consist of a single stand-alone Ethernet LAN. Or
112 even two computers hooked up using a null-modem cable. In these cases,
114 obvious that the network is @emph{private}, no one can access it from the
115 outside. But if your computers are linked to the Internet, the network
116 is not private anymore, unless one uses firewalls to block all private
117 traffic. But then, there is no way to send private data to trusted
118 computers on the other end of the Internet.
121 This problem can be solved by using @emph{virtual} networks. Virtual
122 networks can live on top of other networks, but they use encapsulation to
123 keep using their private address space so they do not interfere with
124 the Internet. Mostly, virtual networks appear like a singe LAN, even though
125 they can span the entire world. But virtual networks can't be secured
126 by using firewalls, because the traffic that flows through it has to go
127 through the Internet, where other people can look at it.
129 As is the case with either type of VPN, anybody could eavesdrop. Or
130 worse, alter data. Hence it's probably advisable to encrypt the data
131 that flows over the network.
133 When one introduces encryption, we can form a true VPN. Other people may
134 see encrypted traffic, but if they don't know how to decipher it (they
135 need to know the key for that), they cannot read the information that flows
136 through the VPN. This is what tinc was made for.
139 @c ==================================================================
144 I really don't quite remember what got us started, but it must have been
145 Guus' idea. He wrote a simple implementation (about 50 lines of C) that
146 used the ethertap device that Linux knows of since somewhere
147 about kernel 2.1.60. It didn't work immediately and he improved it a
148 bit. At this stage, the project was still simply called "vpnd".
150 Since then, a lot has changed---to say the least.
153 Tinc now supports encryption, it consists of a single daemon (tincd) for
154 both the receiving and sending end, it has become largely
155 runtime-configurable---in short, it has become a full-fledged
156 professional package.
158 @cindex traditional VPNs
160 Tinc also allows more than two sites to connect to eachother and form a single VPN.
161 Traditionally VPNs are created by making tunnels, which only have two endpoints.
162 Larger VPNs with more sites are created by adding more tunnels.
163 Tinc takes another approach: only endpoints are specified,
164 the software itself will take care of creating the tunnels.
165 This allows for easier configuration and improved scalability.
167 A lot can---and will be---changed. We have a number of things that we would like to
168 see in the future releases of tinc. Not everything will be available in
169 the near future. Our first objective is to make tinc work perfectly as
170 it stands, and then add more advanced features.
172 Meanwhile, we're always open-minded towards new ideas. And we're
176 @c ==================================================================
177 @node Supported platforms
178 @section Supported platforms
181 Tinc has been verified to work under Linux, FreeBSD, OpenBSD, NetBSD, MacOS/X (Darwin), Solaris, and Windows (both natively and in a Cygwin environment),
182 with various hardware architectures. These are some of the platforms
183 that are supported by the universal tun/tap device driver or other virtual network device drivers.
184 Without such a driver, tinc will most
185 likely compile and run, but it will not be able to send or receive data
189 For an up to date list of supported platforms, please check the list on
191 @uref{http://www.tinc-vpn.org/platforms}.
199 @c Preparing your system
206 @c ==================================================================
208 @chapter Preparations
210 This chapter contains information on how to prepare your system to
214 * Configuring the kernel::
219 @c ==================================================================
220 @node Configuring the kernel
221 @section Configuring the kernel
224 * Configuration of Linux kernels::
225 * Configuration of FreeBSD kernels::
226 * Configuration of OpenBSD kernels::
227 * Configuration of NetBSD kernels::
228 * Configuration of Solaris kernels::
229 * Configuration of Darwin (MacOS/X) kernels::
230 * Configuration of Windows::
234 @c ==================================================================
235 @node Configuration of Linux kernels
236 @subsection Configuration of Linux kernels
238 @cindex Universal tun/tap
239 For tinc to work, you need a kernel that supports the Universal tun/tap device.
240 Most distributions come with kernels that already support this.
241 Here are the options you have to turn on when configuring a new kernel:
244 Code maturity level options
245 [*] Prompt for development and/or incomplete code/drivers
246 Network device support
247 <M> Universal tun/tap device driver support
250 It's not necessary to compile this driver as a module, even if you are going to
251 run more than one instance of tinc.
253 If you decide to build the tun/tap driver as a kernel module, add these lines
254 to @file{/etc/modules.conf}:
257 alias char-major-10-200 tun
261 @c ==================================================================
262 @node Configuration of FreeBSD kernels
263 @subsection Configuration of FreeBSD kernels
265 For FreeBSD version 4.1 and higher, tun and tap drivers are included in the default kernel configuration.
266 Using tap devices is recommended.
269 @c ==================================================================
270 @node Configuration of OpenBSD kernels
271 @subsection Configuration of OpenBSD kernels
273 For OpenBSD version 2.9 and higher,
274 the tun driver is included in the default kernel configuration.
275 There is also a kernel patch from @uref{http://diehard.n-r-g.com/stuff/openbsd/}
276 which adds a tap device to OpenBSD which should work with tinc,
277 but with recent versions of OpenBSD,
278 a tun device can act as a tap device by setting the link0 option with ifconfig.
280 @c ==================================================================
281 @node Configuration of NetBSD kernels
282 @subsection Configuration of NetBSD kernels
284 For NetBSD version 1.5.2 and higher,
285 the tun driver is included in the default kernel configuration.
287 Tunneling IPv6 may not work on NetBSD's tun device.
290 @c ==================================================================
291 @node Configuration of Solaris kernels
292 @subsection Configuration of Solaris kernels
294 For Solaris 8 (SunOS 5.8) and higher,
295 the tun driver may or may not be included in the default kernel configuration.
296 If it isn't, the source can be downloaded from @uref{http://vtun.sourceforge.net/tun/}.
297 For x86 and sparc64 architectures, precompiled versions can be found at @uref{http://www.monkey.org/~dugsong/fragroute/}.
298 If the @file{net/if_tun.h} header file is missing, install it from the source package.
301 @c ==================================================================
302 @node Configuration of Darwin (MacOS/X) kernels
303 @subsection Configuration of Darwin (MacOS/X) kernels
305 Tinc on Darwin relies on a tunnel driver for its data acquisition from the kernel.
306 Tinc supports either the driver from @uref{http://tuntaposx.sourceforge.net/},
307 which supports both tun and tap style devices,
308 and also the driver from from @uref{http://chrisp.de/en/projects/tunnel.html}.
309 The former driver is recommended.
310 The tunnel driver must be loaded before starting tinc with the following command:
317 @c ==================================================================
318 @node Configuration of Windows
319 @subsection Configuration of Windows
321 You will need to install the latest TAP-Win32 driver from OpenVPN.
322 You can download it from @uref{http://openvpn.sourceforge.net}.
323 Using the Network Connections control panel,
324 configure the TAP-Win32 network interface in the same way as you would do from the tinc-up script,
325 as explained in the rest of the documentation.
328 @c ==================================================================
334 Before you can configure or build tinc, you need to have the OpenSSL,
335 zlib and lzo libraries installed on your system. If you try to configure tinc without
336 having them installed, configure will give you an error message, and stop.
346 @c ==================================================================
351 For all cryptography-related functions, tinc uses the functions provided
352 by the OpenSSL library.
354 If this library is not installed, you wil get an error when configuring
355 tinc for build. Support for running tinc without having OpenSSL
356 installed @emph{may} be added in the future.
358 You can use your operating system's package manager to install this if
359 available. Make sure you install the development AND runtime versions
362 If you have to install OpenSSL manually, you can get the source code
363 from @url{http://www.openssl.org/}. Instructions on how to configure,
364 build and install this package are included within the package. Please
365 make sure you build development and runtime libraries (which is the
368 If you installed the OpenSSL libraries from source, it may be necessary
369 to let configure know where they are, by passing configure one of the
370 --with-openssl-* parameters.
373 --with-openssl=DIR OpenSSL library and headers prefix
374 --with-openssl-include=DIR OpenSSL headers directory
375 (Default is OPENSSL_DIR/include)
376 --with-openssl-lib=DIR OpenSSL library directory
377 (Default is OPENSSL_DIR/lib)
381 @subsubheading License
384 The complete source code of tinc is covered by the GNU GPL version 2.
385 Since the license under which OpenSSL is distributed is not directly
386 compatible with the terms of the GNU GPL
387 @uref{http://www.openssl.org/support/faq.html#LEGAL2}, we
388 include an exemption to the GPL (see also the file COPYING.README) to allow
389 everyone to create a statically or dynamically linked executable:
392 This program is released under the GPL with the additional exemption
393 that compiling, linking, and/or using OpenSSL is allowed. You may
394 provide binary packages linked to the OpenSSL libraries, provided that
395 all other requirements of the GPL are met.
398 Since the LZO library used by tinc is also covered by the GPL,
399 we also present the following exemption:
402 Hereby I grant a special exception to the tinc VPN project
403 (http://www.tinc-vpn.org/) to link the LZO library with the OpenSSL library
404 (http://www.openssl.org).
406 Markus F.X.J. Oberhumer
410 @c ==================================================================
415 For the optional compression of UDP packets, tinc uses the functions provided
418 If this library is not installed, you wil get an error when configuring
419 tinc for build. Support for running tinc without having zlib
420 installed @emph{may} be added in the future.
422 You can use your operating system's package manager to install this if
423 available. Make sure you install the development AND runtime versions
426 If you have to install zlib manually, you can get the source code
427 from @url{http://www.gzip.org/zlib/}. Instructions on how to configure,
428 build and install this package are included within the package. Please
429 make sure you build development and runtime libraries (which is the
433 @c ==================================================================
438 Another form of compression is offered using the lzo library.
440 If this library is not installed, you wil get an error when configuring
441 tinc for build. Support for running tinc without having lzo
442 installed @emph{may} be added in the future.
444 You can use your operating system's package manager to install this if
445 available. Make sure you install the development AND runtime versions
448 If you have to install lzo manually, you can get the source code
449 from @url{http://www.oberhumer.com/opensource/lzo/}. Instructions on how to configure,
450 build and install this package are included within the package. Please
451 make sure you build development and runtime libraries (which is the
455 @c ==================================================================
460 For the main event loop, tinc uses the libevent library.
462 If this library is not installed, you wil get an error when configuring
465 You can use your operating system's package manager to install this if
466 available. Make sure you install the development AND runtime versions
469 If you have to install libevent manually, you can get the source code
470 from @url{http://monkey.org/~provos/libevent/}. Instructions on how to configure,
471 build and install this package are included within the package. Please
472 make sure you build development and runtime libraries (which is the
485 @c ==================================================================
487 @chapter Installation
489 If you use Debian, you may want to install one of the
490 precompiled packages for your system. These packages are equipped with
491 system startup scripts and sample configurations.
493 If you cannot use one of the precompiled packages, or you want to compile tinc
494 for yourself, you can use the source. The source is distributed under
495 the GNU General Public License (GPL). Download the source from the
496 @uref{http://www.tinc-vpn.org/download, download page}, which has
497 the checksums of these files listed; you may wish to check these with
498 md5sum before continuing.
500 Tinc comes in a convenient autoconf/automake package, which you can just
501 treat the same as any other package. Which is just untar it, type
502 `./configure' and then `make'.
503 More detailed instructions are in the file @file{INSTALL}, which is
504 included in the source distribution.
507 * Building and installing tinc::
512 @c ==================================================================
513 @node Building and installing tinc
514 @section Building and installing tinc
516 Detailed instructions on configuring the source, building tinc and installing tinc
517 can be found in the file called @file{INSTALL}.
519 @cindex binary package
520 If you happen to have a binary package for tinc for your distribution,
521 you can use the package management tools of that distribution to install tinc.
522 The documentation that comes along with your distribution will tell you how to do that.
525 * Darwin (MacOS/X) build environment::
526 * Cygwin (Windows) build environment::
527 * MinGW (Windows) build environment::
531 @c ==================================================================
532 @node Darwin (MacOS/X) build environment
533 @subsection Darwin (MacOS/X) build environment
535 In order to build tinc on Darwin, you need to install the MacOS/X Developer Tools
536 from @uref{http://developer.apple.com/tools/macosxtools.html} and
537 a recent version of Fink from @uref{http://fink.sourceforge.net/}.
539 After installation use fink to download and install the following packages:
540 autoconf25, automake, dlcompat, m4, openssl, zlib and lzo.
542 @c ==================================================================
543 @node Cygwin (Windows) build environment
544 @subsection Cygwin (Windows) build environment
546 If Cygwin hasn't already been installed, install it directly from
547 @uref{http://www.cygwin.com/}.
549 When tinc is compiled in a Cygwin environment, it can only be run in this environment,
550 but all programs, including those started outside the Cygwin environment, will be able to use the VPN.
551 It will also support all features.
553 @c ==================================================================
554 @node MinGW (Windows) build environment
555 @subsection MinGW (Windows) build environment
557 You will need to install the MinGW environment from @uref{http://www.mingw.org}.
559 When tinc is compiled using MinGW it runs natively under Windows,
560 it is not necessary to keep MinGW installed.
562 When detaching, tinc will install itself as a service,
563 which will be restarted automatically after reboots.
566 @c ==================================================================
568 @section System files
570 Before you can run tinc, you must make sure you have all the needed
571 files on your system.
579 @c ==================================================================
581 @subsection Device files
584 Most operating systems nowadays come with the necessary device files by default,
585 or they have a mechanism to create them on demand.
587 If you use Linux and do not have udev installed,
588 you may need to create the following device file if it does not exist:
591 mknod -m 600 /dev/net/tun c 10 200
595 @c ==================================================================
597 @subsection Other files
599 @subsubheading @file{/etc/networks}
601 You may add a line to @file{/etc/networks} so that your VPN will get a
602 symbolic name. For example:
608 @subsubheading @file{/etc/services}
611 You may add this line to @file{/etc/services}. The effect is that you
612 may supply a @samp{tinc} as a valid port number to some programs. The
613 number 655 is registered with the IANA.
618 # Ivo Timmermans <ivo@@tinc-vpn.org>
633 @c ==================================================================
635 @chapter Configuration
638 * Configuration introduction::
639 * Multiple networks::
640 * How connections work::
641 * Configuration files::
642 * Generating keypairs::
643 * Network interfaces::
644 * Example configuration::
647 @c ==================================================================
648 @node Configuration introduction
649 @section Configuration introduction
651 Before actually starting to configure tinc and editing files,
652 make sure you have read this entire section so you know what to expect.
653 Then, make it clear to yourself how you want to organize your VPN:
654 What are the nodes (computers running tinc)?
655 What IP addresses/subnets do they have?
656 What is the network mask of the entire VPN?
657 Do you need special firewall rules?
658 Do you have to set up masquerading or forwarding rules?
659 Do you want to run tinc in router mode or switch mode?
660 These questions can only be answered by yourself,
661 you will not find the answers in this documentation.
662 Make sure you have an adequate understanding of networks in general.
663 @cindex Network Administrators Guide
664 A good resource on networking is the
665 @uref{http://www.linuxdoc.org/LDP/nag2/, Linux Network Administrators Guide}.
667 If you have everything clearly pictured in your mind,
668 proceed in the following order:
669 First, generate the configuration files (@file{tinc.conf}, your host configuration file, @file{tinc-up} and perhaps @file{tinc-down}).
670 Then generate the keypairs.
671 Finally, distribute the host configuration files.
672 These steps are described in the subsections below.
675 @c ==================================================================
676 @node Multiple networks
677 @section Multiple networks
679 @cindex multiple networks
681 In order to allow you to run more than one tinc daemon on one computer,
682 for instance if your computer is part of more than one VPN,
683 you can assign a @var{netname} to your VPN.
684 It is not required if you only run one tinc daemon,
685 it doesn't even have to be the same on all the sites of your VPN,
686 but it is recommended that you choose one anyway.
688 We will asume you use a netname throughout this document.
689 This means that you call tincd with the -n argument,
690 which will assign a netname to this daemon.
692 The effect of this is that the daemon will set its configuration
693 root to @file{@value{sysconfdir}/tinc/@var{netname}/}, where @var{netname} is your argument to the -n
694 option. You'll notice that it appears in syslog as @file{tinc.@var{netname}}.
696 However, it is not strictly necessary that you call tinc with the -n
697 option. In this case, the network name would just be empty, and it will
698 be used as such. tinc now looks for files in @file{@value{sysconfdir}/tinc/}, instead of
699 @file{@value{sysconfdir}/tinc/@var{netname}/}; the configuration file should be @file{@value{sysconfdir}/tinc/tinc.conf},
700 and the host configuration files are now expected to be in @file{@value{sysconfdir}/tinc/hosts/}.
702 But it is highly recommended that you use this feature of tinc, because
703 it will be so much clearer whom your daemon talks to. Hence, we will
704 assume that you use it.
707 @c ==================================================================
708 @node How connections work
709 @section How connections work
711 When tinc starts up, it parses the command-line options and then
712 reads in the configuration file tinc.conf.
713 If it sees one or more `ConnectTo' values pointing to other tinc daemons in that file,
714 it will try to connect to those other daemons.
715 Whether this succeeds or not and whether `ConnectTo' is specified or not,
716 tinc will listen for incoming connection from other deamons.
717 If you did specify a `ConnectTo' value and the other side is not responding,
718 tinc will keep retrying.
719 This means that once started, tinc will stay running until you tell it to stop,
720 and failures to connect to other tinc daemons will not stop your tinc daemon
721 for trying again later.
722 This means you don't have to intervene if there are temporary network problems.
726 There is no real distinction between a server and a client in tinc.
727 If you wish, you can view a tinc daemon without a `ConnectTo' value as a server,
728 and one which does specify such a value as a client.
729 It does not matter if two tinc daemons have a `ConnectTo' value pointing to each other however.
732 @c ==================================================================
733 @node Configuration files
734 @section Configuration files
736 The actual configuration of the daemon is done in the file
737 @file{@value{sysconfdir}/tinc/@var{netname}/tinc.conf} and at least one other file in the directory
738 @file{@value{sysconfdir}/tinc/@var{netname}/hosts/}.
740 These file consists of comments (lines started with a #) or assignments
747 The variable names are case insensitive, and any spaces, tabs, newlines
748 and carriage returns are ignored. Note: it is not required that you put
749 in the `=' sign, but doing so improves readability. If you leave it
750 out, remember to replace it with at least one space character.
752 In this section all valid variables are listed in alphabetical order.
753 The default value is given between parentheses,
754 other comments are between square brackets.
757 * Main configuration variables::
758 * Host configuration variables::
764 @c ==================================================================
765 @node Main configuration variables
766 @subsection Main configuration variables
769 @cindex AddressFamily
770 @item AddressFamily = <ipv4|ipv6|any> (any)
771 This option affects the address family of listening and outgoing sockets.
772 If any is selected, then depending on the operating system
773 both IPv4 and IPv6 or just IPv6 listening sockets will be created.
775 @cindex BindToAddress
776 @item BindToAddress = <@var{address}> [experimental]
777 If your computer has more than one IPv4 or IPv6 address, tinc
778 will by default listen on all of them for incoming connections.
779 It is possible to bind only to a single address with this variable.
781 This option may not work on all platforms.
783 @cindex BindToInterface
784 @item BindToInterface = <@var{interface}> [experimental]
785 If you have more than one network interface in your computer, tinc will
786 by default listen on all of them for incoming connections. It is
787 possible to bind tinc to a single interface like eth0 or ppp0 with this
790 This option may not work on all platforms.
793 @item ConnectTo = <@var{name}>
794 Specifies which other tinc daemon to connect to on startup.
795 Multiple ConnectTo variables may be specified,
796 in which case outgoing connections to each specified tinc daemon are made.
797 The names should be known to this tinc daemon
798 (i.e., there should be a host configuration file for the name on the ConnectTo line).
800 If you don't specify a host with ConnectTo,
801 tinc won't try to connect to other daemons at all,
802 and will instead just listen for incoming connections.
805 @item Device = <@var{device}> (@file{/dev/tap0}, @file{/dev/net/tun} or other depending on platform)
806 The virtual network device to use.
807 Tinc will automatically detect what kind of device it is.
808 Note that you can only use one device per daemon.
809 Under Windows, use @var{Interface} instead of @var{Device}.
810 Note that you can only use one device per daemon.
811 See also @ref{Device files}.
814 @item DeviceType = <tun|tunnohead|tunifhead|tap> (only supported on BSD platforms)
815 The type of the virtual network device.
816 Tinc will normally automatically select the right type, and this option should not be used.
817 However, in case tinc does not seem to correctly interpret packets received from the virtual network device,
818 using this option might help.
823 Depending on the platform, this can either be with or without an address family header (see below).
827 Set type to tun without an address family header.
828 Tinc will expect packets read from the virtual network device to start with an IP header.
829 On some platforms IPv6 packets cannot be read from or written to the device in this mode.
833 Set type to tun with an address family header.
834 Tinc will expect packets read from the virtual network device
835 to start with a four byte header containing the address family,
836 followed by an IP header.
837 This mode should support both IPv4 and IPv6 packets.
841 Tinc will expect packets read from the virtual network device
842 to start with an Ethernet header.
845 @cindex GraphDumpFile
846 @item GraphDumpFile = <@var{filename}> [experimental]
847 If this option is present,
848 tinc will dump the current network graph to the file @var{filename}
849 every minute, unless there were no changes to the graph.
850 The file is in a format that can be read by graphviz tools.
851 If @var{filename} starts with a pipe symbol |,
852 then the rest of the filename is interpreted as a shell command
853 that is executed, the graph is then sent to stdin.
856 @item Hostnames = <yes|no> (no)
857 This option selects whether IP addresses (both real and on the VPN)
858 should be resolved. Since DNS lookups are blocking, it might affect
859 tinc's efficiency, even stopping the daemon for a few seconds everytime
860 it does a lookup if your DNS server is not responding.
862 This does not affect resolving hostnames to IP addresses from the
866 @item Interface = <@var{interface}>
867 Defines the name of the interface corresponding to the virtual network device.
868 Depending on the operating system and the type of device this may or may not actually set the name of the interface.
869 Under Windows, this variable is used to select which network interface will be used.
870 If you specified a Device, this variable is almost always already correctly set.
873 @item Mode = <router|switch|hub> (router)
874 This option selects the way packets are routed to other daemons.
880 variables in the host configuration files will be used to form a routing table.
881 Only unicast packets of routable protocols (IPv4 and IPv6) are supported in this mode.
883 This is the default mode, and unless you really know you need another mode, don't change it.
887 In this mode the MAC addresses of the packets on the VPN will be used to
888 dynamically create a routing table just like an Ethernet switch does.
889 Unicast, multicast and broadcast packets of every protocol that runs over Ethernet are supported in this mode
890 at the cost of frequent broadcast ARP requests and routing table updates.
892 This mode is primarily useful if you want to bridge Ethernet segments.
896 This mode is almost the same as the switch mode, but instead
897 every packet will be broadcast to the other daemons
898 while no routing table is managed.
902 @item KeyExpire = <@var{seconds}> (3600)
903 This option controls the time the encryption keys used to encrypt the data
904 are valid. It is common practice to change keys at regular intervals to
905 make it even harder for crackers, even though it is thought to be nearly
906 impossible to crack a single key.
909 @item MACExpire = <@var{seconds}> (600)
910 This option controls the amount of time MAC addresses are kept before they are removed.
911 This only has effect when Mode is set to "switch".
914 @item Name = <@var{name}> [required]
915 This is a symbolic name for this connection.
916 The name should consist only of alfanumeric and underscore characters (a-z, A-Z, 0-9 and _).
919 @item PingInterval = <@var{seconds}> (60)
920 The number of seconds of inactivity that tinc will wait before sending a
921 probe to the other end.
924 @item PingTimeout = <@var{seconds}> (5)
925 The number of seconds to wait for a response to pings or to allow meta
926 connections to block. If the other end doesn't respond within this time,
927 the connection is terminated, and the others will be notified of this.
929 @cindex PriorityInheritance
930 @item PriorityInheritance = <yes|no> (no) [experimental]
931 When this option is enabled the value of the TOS field of tunneled IPv4 packets
932 will be inherited by the UDP packets that are sent out.
935 @item PrivateKey = <@var{key}> [obsolete]
936 This is the RSA private key for tinc. However, for safety reasons it is
937 advised to store private keys of any kind in separate files. This prevents
938 accidental eavesdropping if you are editting the configuration file.
940 @cindex PrivateKeyFile
941 @item PrivateKeyFile = <@var{path}> (@file{@value{sysconfdir}/tinc/@var{netname}/rsa_key.priv})
942 This is the full path name of the RSA private key file that was
943 generated by @samp{tincctl generate-keys}. It must be a full path, not a
946 Note that there must be exactly one of PrivateKey
948 specified in the configuration file.
950 @cindex ProcessPriority
951 @item ProcessPriority = <low|normal|high>
952 When this option is used the priority of the tincd process will be adjusted.
953 Increasing the priority may help to reduce latency and packet loss on the VPN.
956 @item TunnelServer = <yes|no> (no) [experimental]
957 When this option is enabled tinc will no longer forward information between other tinc daemons,
958 and will only allow nodes and subnets on the VPN which are present in the
959 @file{@value{sysconfdir}/tinc/@var{netname}/hosts/} directory.
964 @c ==================================================================
965 @node Host configuration variables
966 @subsection Host configuration variables
970 @item Address = <@var{IP address}|@var{hostname}> [recommended]
971 This variable is only required if you want to connect to this host. It
972 must resolve to the external IP address where the host can be reached,
973 not the one that is internal to the VPN.
976 @item Cipher = <@var{cipher}> (blowfish)
977 The symmetric cipher algorithm used to encrypt UDP packets.
978 Any cipher supported by OpenSSL is recognized.
979 Furthermore, specifying "none" will turn off packet encryption.
980 It is best to use only those ciphers which support CBC mode.
983 @item Compression = <@var{level}> (0)
984 This option sets the level of compression used for UDP packets.
985 Possible values are 0 (off), 1 (fast zlib) and any integer up to 9 (best zlib),
986 10 (fast lzo) and 11 (best lzo).
989 @item Digest = <@var{digest}> (sha1)
990 The digest algorithm used to authenticate UDP packets.
991 Any digest supported by OpenSSL is recognized.
992 Furthermore, specifying "none" will turn off packet authentication.
995 @item IndirectData = <yes|no> (no)
996 This option specifies whether other tinc daemons besides the one you
997 specified with ConnectTo can make a direct connection to you. This is
998 especially useful if you are behind a firewall and it is impossible to
999 make a connection from the outside to your tinc daemon. Otherwise, it
1000 is best to leave this option out or set it to no.
1003 @item MACLength = <@var{bytes}> (4)
1004 The length of the message authentication code used to authenticate UDP packets.
1005 Can be anything from 0
1006 up to the length of the digest produced by the digest algorithm.
1009 @item PMTU = <@var{mtu}> (1514)
1010 This option controls the initial path MTU to this node.
1012 @cindex PMTUDiscovery
1013 @item PMTUDiscovery = <yes|no> (yes)
1014 When this option is enabled, tinc will try to discover the path MTU to this node.
1015 After the path MTU has been discovered, it will be enforced on the VPN.
1018 @item Port = <@var{port}> (655)
1019 This is the port this tinc daemon listens on.
1020 You can use decimal portnumbers or symbolic names (as listed in @file{/etc/services}).
1023 @item PublicKey = <@var{key}> [obsolete]
1024 This is the RSA public key for this host.
1026 @cindex PublicKeyFile
1027 @item PublicKeyFile = <@var{path}> [obsolete]
1028 This is the full path name of the RSA public key file that was generated
1029 by @samp{tincctl generate-keys}. It must be a full path, not a relative
1033 From version 1.0pre4 on tinc will store the public key directly into the
1034 host configuration file in PEM format, the above two options then are not
1035 necessary. Either the PEM format is used, or exactly
1036 @strong{one of the above two options} must be specified
1037 in each host configuration file, if you want to be able to establish a
1038 connection with that host.
1041 @item Subnet = <@var{address}[/@var{prefixlength}[#@var{weight}]]>
1042 The subnet which this tinc daemon will serve.
1043 Tinc tries to look up which other daemon it should send a packet to by searching the appropiate subnet.
1044 If the packet matches a subnet,
1045 it will be sent to the daemon who has this subnet in his host configuration file.
1046 Multiple subnet lines can be specified for each daemon.
1048 Subnets can either be single MAC, IPv4 or IPv6 addresses,
1049 in which case a subnet consisting of only that single address is assumed,
1050 or they can be a IPv4 or IPv6 network address with a prefixlength.
1051 Shorthand notations are not supported.
1052 For example, IPv4 subnets must be in a form like 192.168.1.0/24,
1053 where 192.168.1.0 is the network address and 24 is the number of bits set in the netmask.
1054 Note that subnets like 192.168.1.1/24 are invalid!
1055 Read a networking HOWTO/FAQ/guide if you don't understand this.
1056 IPv6 subnets are notated like fec0:0:0:1:0:0:0:0/64.
1057 MAC addresses are notated like 0:1a:2b:3c:4d:5e.
1059 @cindex CIDR notation
1060 Prefixlength is the number of bits set to 1 in the netmask part; for
1061 example: netmask 255.255.255.0 would become /24, 255.255.252.0 becomes
1062 /22. This conforms to standard CIDR notation as described in
1063 @uref{ftp://ftp.isi.edu/in-notes/rfc1519.txt, RFC1519}
1065 A Subnet can be given a weight to indicate its priority over identical Subnets
1066 owned by different nodes. The default weight is 10. Lower values indicate
1067 higher priority. Packets will be sent to the node with the highest priority,
1068 unless that node is not reachable, in which case the node with the next highest
1069 priority will be tried, and so on.
1072 @item TCPonly = <yes|no> (no)
1073 If this variable is set to yes, then the packets are tunnelled over a
1074 TCP connection instead of a UDP connection. This is especially useful
1075 for those who want to run a tinc daemon from behind a masquerading
1076 firewall, or if UDP packet routing is disabled somehow.
1077 Setting this options also implicitly sets IndirectData.
1081 @c ==================================================================
1086 Apart from reading the server and host configuration files,
1087 tinc can also run scripts at certain moments.
1088 Under Windows (not Cygwin), the scripts should have the extension .bat.
1092 @item @value{sysconfdir}/tinc/@var{netname}/tinc-up
1093 This is the most important script.
1094 If it is present it will be executed right after the tinc daemon has been
1095 started and has connected to the virtual network device.
1096 It should be used to set up the corresponding network interface,
1097 but can also be used to start other things.
1098 Under Windows you can use the Network Connections control panel instead of creating this script.
1101 @item @value{sysconfdir}/tinc/@var{netname}/tinc-down
1102 This script is started right before the tinc daemon quits.
1104 @item @value{sysconfdir}/tinc/@var{netname}/hosts/@var{host}-up
1105 This script is started when the tinc daemon with name @var{host} becomes reachable.
1107 @item @value{sysconfdir}/tinc/@var{netname}/hosts/@var{host}-down
1108 This script is started when the tinc daemon with name @var{host} becomes unreachable.
1110 @item @value{sysconfdir}/tinc/@var{netname}/host-up
1111 This script is started when any host becomes reachable.
1113 @item @value{sysconfdir}/tinc/@var{netname}/host-down
1114 This script is started when any host becomes unreachable.
1116 @item @value{sysconfdir}/tinc/@var{netname}/subnet-up
1117 This script is started when a Subnet becomes reachable.
1118 The Subnet and the node it belongs to are passed in environment variables.
1120 @item @value{sysconfdir}/tinc/@var{netname}/subnet-down
1121 This script is started when a Subnet becomes unreachable.
1124 @cindex environment variables
1125 The scripts are started without command line arguments,
1126 but can make use of certain environment variables.
1127 Under UNIX like operating systems the names of environment variables must be preceded by a $ in scripts.
1128 Under Windows, in @file{.bat} files, they have to be put between % signs.
1133 If a netname was specified, this environment variable contains it.
1137 Contains the name of this tinc daemon.
1141 Contains the name of the virtual network device that tinc uses.
1145 Contains the name of the virtual network interface that tinc uses.
1146 This should be used for commands like ifconfig.
1150 When a host becomes (un)reachable, this is set to its name.
1151 If a subnet becomes (un)reachable, this is set to the owner of that subnet.
1153 @cindex REMOTEADDRESS
1155 When a host becomes (un)reachable, this is set to its real address.
1159 When a host becomes (un)reachable,
1160 this is set to the port number it uses for communication with other tinc daemons.
1164 When a subnet becomes (un)reachable, this is set to the subnet.
1169 @c ==================================================================
1170 @node How to configure
1171 @subsection How to configure
1173 @subsubheading Step 1. Creating the main configuration file
1175 The main configuration file will be called @file{@value{sysconfdir}/tinc/@var{netname}/tinc.conf}.
1176 Adapt the following example to create a basic configuration file:
1179 Name = @var{yourname}
1180 Device = @file{/dev/tap0}
1183 Then, if you know to which other tinc daemon(s) yours is going to connect,
1184 add `ConnectTo' values.
1186 @subsubheading Step 2. Creating your host configuration file
1188 If you added a line containing `Name = yourname' in the main configuarion file,
1189 you will need to create a host configuration file @file{@value{sysconfdir}/tinc/@var{netname}/hosts/yourname}.
1190 Adapt the following example to create a host configuration file:
1193 Address = your.real.hostname.org
1194 Subnet = 192.168.1.0/24
1197 You can also use an IP address instead of a hostname.
1198 The `Subnet' specifies the address range that is local for @emph{your part of the VPN only}.
1199 If you have multiple address ranges you can specify more than one `Subnet'.
1200 You might also need to add a `Port' if you want your tinc daemon to run on a different port number than the default (655).
1203 @c ==================================================================
1204 @node Generating keypairs
1205 @section Generating keypairs
1207 @cindex key generation
1208 Now that you have already created the main configuration file and your host configuration file,
1209 you can easily create a public/private keypair by entering the following command:
1212 tincctl -n @var{netname} generate-keys
1215 Tinc will generate a public and a private key and ask you where to put them.
1216 Just press enter to accept the defaults.
1219 @c ==================================================================
1220 @node Network interfaces
1221 @section Network interfaces
1223 Before tinc can start transmitting data over the tunnel, it must
1224 set up the virtual network interface.
1226 First, decide which IP addresses you want to have associated with these
1227 devices, and what network mask they must have.
1229 Tinc will open a virtual network device (@file{/dev/tun}, @file{/dev/tap0} or similar),
1230 which will also create a network interface called something like @samp{tun0}, @samp{tap0}.
1231 If you are using the Linux tun/tap driver, the network interface will by default have the same name as the @var{netname}.
1232 Under Windows you can change the name of the network interface from the Network Connections control panel.
1235 You can configure the network interface by putting ordinary ifconfig, route, and other commands
1236 to a script named @file{@value{sysconfdir}/tinc/@var{netname}/tinc-up}.
1237 When tinc starts, this script will be executed. When tinc exits, it will execute the script named
1238 @file{@value{sysconfdir}/tinc/@var{netname}/tinc-down}, but normally you don't need to create that script.
1240 An example @file{tinc-up} script:
1244 ifconfig $INTERFACE 192.168.1.1 netmask 255.255.0.0
1247 This script gives the interface an IP address and a netmask.
1248 The kernel will also automatically add a route to this interface, so normally you don't need
1249 to add route commands to the @file{tinc-up} script.
1250 The kernel will also bring the interface up after this command.
1252 The netmask is the mask of the @emph{entire} VPN network, not just your
1255 The exact syntax of the ifconfig and route commands differs from platform to platform.
1256 You can look up the commands for setting addresses and adding routes in @ref{Platform specific information},
1257 but it is best to consult the manpages of those utilities on your platform.
1260 @c ==================================================================
1261 @node Example configuration
1262 @section Example configuration
1266 Imagine the following situation. Branch A of our example `company' wants to connect
1267 three branch offices in B, C and D using the Internet. All four offices
1268 have a 24/7 connection to the Internet.
1270 A is going to serve as the center of the network. B and C will connect
1271 to A, and D will connect to C. Each office will be assigned their own IP
1275 A: net 10.1.0.0 mask 255.255.0.0 gateway 10.1.54.1 internet IP 1.2.3.4
1276 B: net 10.2.0.0 mask 255.255.0.0 gateway 10.2.1.12 internet IP 2.3.4.5
1277 C: net 10.3.0.0 mask 255.255.0.0 gateway 10.3.69.254 internet IP 3.4.5.6
1278 D: net 10.4.0.0 mask 255.255.0.0 gateway 10.4.3.32 internet IP 4.5.6.7
1281 Here, ``gateway'' is the VPN IP address of the machine that is running the
1282 tincd, and ``internet IP'' is the IP address of the firewall, which does not
1283 need to run tincd, but it must do a port forwarding of TCP and UDP on port
1284 655 (unless otherwise configured).
1286 In this example, it is assumed that eth0 is the interface that points to
1287 the inner (physical) LAN of the office, although this could also be the
1288 same as the interface that leads to the Internet. The configuration of
1289 the real interface is also shown as a comment, to give you an idea of
1290 how these example host is set up. All branches use the netname `company'
1291 for this particular VPN.
1293 @subsubheading For Branch A
1295 @emph{BranchA} would be configured like this:
1297 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1300 # Real interface of internal network:
1301 # ifconfig eth0 10.1.54.1 netmask 255.255.0.0
1303 ifconfig $INTERFACE 10.1.54.1 netmask 255.0.0.0
1306 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1313 On all hosts, @file{@value{sysconfdir}/tinc/company/hosts/BranchA} contains:
1316 Subnet = 10.1.0.0/16
1319 -----BEGIN RSA PUBLIC KEY-----
1321 -----END RSA PUBLIC KEY-----
1324 Note that the IP addresses of eth0 and tap0 are the same.
1325 This is quite possible, if you make sure that the netmasks of the interfaces are different.
1326 It is in fact recommended to give give both real internal network interfaces and tap interfaces the same IP address,
1327 since that will make things a lot easier to remember and set up.
1330 @subsubheading For Branch B
1332 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1335 # Real interface of internal network:
1336 # ifconfig eth0 10.2.43.8 netmask 255.255.0.0
1338 ifconfig $INTERFACE 10.2.1.12 netmask 255.0.0.0
1341 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1348 Note here that the internal address (on eth0) doesn't have to be the
1349 same as on the tap0 device. Also, ConnectTo is given so that no-one can
1350 connect to this node.
1352 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchB}:
1355 Subnet = 10.2.0.0/16
1358 -----BEGIN RSA PUBLIC KEY-----
1360 -----END RSA PUBLIC KEY-----
1364 @subsubheading For Branch C
1366 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1369 # Real interface of internal network:
1370 # ifconfig eth0 10.3.69.254 netmask 255.255.0.0
1372 ifconfig $INTERFACE 10.3.69.254 netmask 255.0.0.0
1375 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1383 C already has another daemon that runs on port 655, so they have to
1384 reserve another port for tinc. It knows the portnumber it has to listen on
1385 from it's own host configuration file.
1387 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchC}:
1391 Subnet = 10.3.0.0/16
1394 -----BEGIN RSA PUBLIC KEY-----
1396 -----END RSA PUBLIC KEY-----
1400 @subsubheading For Branch D
1402 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1405 # Real interface of internal network:
1406 # ifconfig eth0 10.4.3.32 netmask 255.255.0.0
1408 ifconfig $INTERFACE 10.4.3.32 netmask 255.0.0.0
1411 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1416 Device = /dev/net/tun
1419 D will be connecting to C, which has a tincd running for this network on
1420 port 2000. It knows the port number from the host configuration file.
1421 Also note that since D uses the tun/tap driver, the network interface
1422 will not be called `tun' or `tap0' or something like that, but will
1423 have the same name as netname.
1425 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchD}:
1428 Subnet = 10.4.0.0/16
1431 -----BEGIN RSA PUBLIC KEY-----
1433 -----END RSA PUBLIC KEY-----
1436 @subsubheading Key files
1438 A, B, C and D all have generated a public/private keypair with the following command:
1441 tincctl -n company generate-keys
1444 The private key is stored in @file{@value{sysconfdir}/tinc/company/rsa_key.priv},
1445 the public key is put into the host configuration file in the @file{@value{sysconfdir}/tinc/company/hosts/} directory.
1446 During key generation, tinc automatically guesses the right filenames based on the -n option and
1447 the Name directive in the @file{tinc.conf} file (if it is available).
1449 @subsubheading Starting
1451 After each branch has finished configuration and they have distributed
1452 the host configuration files amongst them, they can start their tinc daemons.
1453 They don't necessarily have to wait for the other branches to have started
1454 their daemons, tinc will try connecting until they are available.
1457 @c ==================================================================
1459 @chapter Running tinc
1461 If everything else is done, you can start tinc by typing the following command:
1464 tincd -n @var{netname}
1468 Tinc will detach from the terminal and continue to run in the background like a good daemon.
1469 If there are any problems however you can try to increase the debug level
1470 and look in the syslog to find out what the problems are.
1476 * Solving problems::
1478 * Sending bug reports::
1482 @c ==================================================================
1483 @node Runtime options
1484 @section Runtime options
1486 Besides the settings in the configuration file, tinc also accepts some
1487 command line options.
1489 @cindex command line
1490 @cindex runtime options
1494 @item -c, --config=@var{path}
1495 Read configuration options from the directory @var{path}. The default is
1496 @file{@value{sysconfdir}/tinc/@var{netname}/}.
1498 @item -D, --no-detach
1499 Don't fork and detach.
1500 This will also disable the automatic restart mechanism for fatal errors.
1503 @item -d, --debug=@var{level}
1504 Set debug level to @var{level}. The higher the debug level, the more gets
1505 logged. Everything goes via syslog.
1507 @item -n, --net=@var{netname}
1508 Use configuration for net @var{netname}. @xref{Multiple networks}.
1510 @item --controlsocket=@var{filename}
1511 Open control socket at @var{filename}. If unspecified, the default is
1512 @file{@value{localstatedir}/run/tinc.@var{netname}.control}.
1515 Lock tinc into main memory.
1516 This will prevent sensitive data like shared private keys to be written to the system swap files/partitions.
1518 @item --logfile[=@var{file}]
1519 Write log entries to a file instead of to the system logging facility.
1520 If @var{file} is omitted, the default is @file{@value{localstatedir}/log/tinc.@var{netname}.log}.
1522 @item --bypass-security
1523 Disables encryption and authentication.
1524 Only useful for debugging.
1527 Change process root directory to the directory where the config file is
1528 located (@file{@value{sysconfdir}/tinc/@var{netname}/} as determined by
1529 -n/--net option or as given by -c/--config option), for added security.
1530 The chroot is performed after all the initialization is done, after
1531 writing pid files and opening network sockets.
1533 Note that this option alone does not do any good without -U/--user, below.
1535 Note also that tinc can't run scripts anymore (such as tinc-down or host-up),
1536 unless it's setup to be runnable inside chroot environment.
1538 @item -U, --user=@var{user}
1539 Switch to the given @var{user} after initialization, at the same time as
1540 chroot is performed (see --chroot above). With this option tinc drops
1541 privileges, for added security.
1544 Display a short reminder of these runtime options and terminate.
1547 Output version information and exit.
1551 @c ==================================================================
1556 You can also send the following signals to a running tincd process:
1562 Partially rereads configuration files.
1563 Connections to hosts whose host config file are removed are closed.
1564 New outgoing connections specified in @file{tinc.conf} will be made.
1568 @c ==================================================================
1570 @section Debug levels
1572 @cindex debug levels
1573 The tinc daemon can send a lot of messages to the syslog.
1574 The higher the debug level, the more messages it will log.
1575 Each level inherits all messages of the previous level:
1581 This will log a message indicating tinc has started along with a version number.
1582 It will also log any serious error.
1585 This will log all connections that are made with other tinc daemons.
1588 This will log status and error messages from scripts and other tinc daemons.
1591 This will log all requests that are exchanged with other tinc daemons. These include
1592 authentication, key exchange and connection list updates.
1595 This will log a copy of everything received on the meta socket.
1598 This will log all network traffic over the virtual private network.
1602 @c ==================================================================
1603 @node Solving problems
1604 @section Solving problems
1606 If tinc starts without problems, but if the VPN doesn't work, you will have to find the cause of the problem.
1607 The first thing to do is to start tinc with a high debug level in the foreground,
1608 so you can directly see everything tinc logs:
1611 tincd -n @var{netname} -d5 -D
1614 If tinc does not log any error messages, then you might want to check the following things:
1617 @item @file{tinc-up} script
1618 Does this script contain the right commands?
1619 Normally you must give the interface the address of this host on the VPN, and the netmask must be big enough so that the entire VPN is covered.
1622 Does the Subnet (or Subnets) in the host configuration file of this host match the portion of the VPN that belongs to this host?
1624 @item Firewalls and NATs
1625 Do you have a firewall or a NAT device (a masquerading firewall or perhaps an ADSL router that performs masquerading)?
1626 If so, check that it allows TCP and UDP traffic on port 655.
1627 If it masquerades and the host running tinc is behind it, make sure that it forwards TCP and UDP traffic to port 655 to the host running tinc.
1628 You can add @samp{TCPOnly = yes} to your host config file to force tinc to only use a single TCP connection,
1629 this works through most firewalls and NATs.
1634 @c ==================================================================
1635 @node Error messages
1636 @section Error messages
1638 What follows is a list of the most common error messages you might find in the logs.
1639 Some of them will only be visible if the debug level is high enough.
1642 @item Could not open /dev/tap0: No such device
1645 @item You forgot to `modprobe netlink_dev' or `modprobe ethertap'.
1646 @item You forgot to compile `Netlink device emulation' in the kernel.
1649 @item Can't write to /dev/net/tun: No such device
1652 @item You forgot to `modprobe tun'.
1653 @item You forgot to compile `Universal TUN/TAP driver' in the kernel.
1654 @item The tun device is located somewhere else in @file{/dev/}.
1657 @item Network address and prefix length do not match!
1660 @item The Subnet field must contain a @emph{network} address, trailing bits should be 0.
1661 @item If you only want to use one IP address, set the netmask to /32.
1664 @item Error reading RSA key file `rsa_key.priv': No such file or directory
1667 @item You forgot to create a public/private keypair.
1668 @item Specify the complete pathname to the private key file with the @samp{PrivateKeyFile} option.
1671 @item Warning: insecure file permissions for RSA private key file `rsa_key.priv'!
1674 @item The private key file is readable by users other than root.
1675 Use chmod to correct the file permissions.
1678 @item Creating metasocket failed: Address family not supported
1681 @item By default tinc tries to create both IPv4 and IPv6 sockets.
1682 On some platforms this might not be implemented.
1683 If the logs show @samp{Ready} later on, then at least one metasocket was created,
1684 and you can ignore this message.
1685 You can add @samp{AddressFamily = ipv4} to @file{tinc.conf} to prevent this from happening.
1688 @item Cannot route packet: unknown IPv4 destination 1.2.3.4
1691 @item You try to send traffic to a host on the VPN for which no Subnet is known.
1692 @item If it is a broadcast address (ending in .255), it probably is a samba server or a Windows host sending broadcast packets.
1696 @item Cannot route packet: ARP request for unknown address 1.2.3.4
1699 @item You try to send traffic to a host on the VPN for which no Subnet is known.
1702 @item Packet with destination 1.2.3.4 is looping back to us!
1705 @item Something is not configured right. Packets are being sent out to the
1706 virtual network device, but according to the Subnet directives in your host configuration
1707 file, those packets should go to your own host. Most common mistake is that
1708 you have a Subnet line in your host configuration file with a prefix length which is
1709 just as large as the prefix of the virtual network interface. The latter should in almost all
1710 cases be larger. Rethink your configuration.
1711 Note that you will only see this message if you specified a debug
1712 level of 5 or higher!
1713 @item Chances are that a @samp{Subnet = ...} line in the host configuration file of this tinc daemon is wrong.
1714 Change it to a subnet that is accepted locally by another interface,
1715 or if that is not the case, try changing the prefix length into /32.
1718 @item Node foo (1.2.3.4) is not reachable
1721 @item Node foo does not have a connection anymore, its tinc daemon is not running or its connection to the Internet is broken.
1724 @item Received UDP packet from unknown source 1.2.3.4 (port 12345)
1727 @item If you see this only sporadically, it is harmless and caused by a node sending packets using an old key.
1728 @item If you see this often and another node is not reachable anymore, then a NAT (masquerading firewall) is changing the source address of UDP packets.
1729 You can add @samp{TCPOnly = yes} to host configuration files to force all VPN traffic to go over a TCP connection.
1732 @item Got bad/bogus/unauthorized REQUEST from foo (1.2.3.4 port 12345)
1735 @item Node foo does not have the right public/private keypair.
1736 Generate new keypairs and distribute them again.
1737 @item An attacker tries to gain access to your VPN.
1738 @item A network error caused corruption of metadata sent from foo.
1743 @c ==================================================================
1744 @node Sending bug reports
1745 @section Sending bug reports
1747 If you really can't find the cause of a problem, or if you suspect tinc is not working right,
1748 you can send us a bugreport, see @ref{Contact information}.
1749 Be sure to include the following information in your bugreport:
1752 @item A clear description of what you are trying to achieve and what the problem is.
1753 @item What platform (operating system, version, hardware architecture) and which version of tinc you use.
1754 @item If compiling tinc fails, a copy of @file{config.log} and the error messages you get.
1755 @item Otherwise, a copy of @file{tinc.conf}, @file{tinc-up} and all files in the @file{hosts/} directory.
1756 @item The output of the commands @samp{ifconfig -a} and @samp{route -n} (or @samp{netstat -rn} if that doesn't work).
1757 @item The output of any command that fails to work as it should (like ping or traceroute).
1760 @c ==================================================================
1761 @node Controlling tinc
1762 @chapter Controlling tinc
1764 You can control and inspect a running @samp{tincd} through the @samp{tincctl}
1765 command. A quick example:
1768 tincctl -n @var{netname} reload
1772 * tincctl runtime options::
1773 * tincctl commands::
1777 @c ==================================================================
1778 @node tincctl runtime options
1779 @section tincctl runtime options
1783 @item -c, --config=@var{path}
1784 Read configuration options from the directory @var{path}. The default is
1785 @file{@value{sysconfdir}/tinc/@var{netname}/}.
1787 @item -n, --net=@var{netname}
1788 Use configuration for net @var{netname}. @xref{Multiple networks}.
1790 @item --controlsocket=@var{filename}
1791 Open control socket at @var{filename}. If unspecified, the default is
1792 @file{@value{localstatedir}/run/tinc.@var{netname}.control}.
1795 Display a short reminder of runtime options and commands, then terminate.
1798 Output version information and exit.
1803 @c ==================================================================
1804 @node tincctl commands
1805 @section tincctl commands
1817 Restart @samp{tincd}.
1820 Partially rereads configuration files. Connections to hosts whose host
1821 config files are removed are closed. New outgoing connections specified
1822 in @file{tinc.conf} will be made.
1825 Shows the PID of the currently running @samp{tincd}.
1827 @item generate-keys [@var{bits}]
1828 Generate public/private keypair of @var{bits} length. If @var{bits} is not specified,
1829 1024 is the default. tinc will ask where you want to store the files,
1830 but will default to the configuration directory (you can use the -c or -n
1834 Dump a list of all known nodes in the VPN.
1837 Dump a list of all known connections in the VPN.
1840 Dump a list of all known subnets in the VPN.
1842 @item dump connections
1843 Dump a list of all meta connections with ourself.
1846 Dump a graph of the VPN in dotty format.
1849 Purges all information remembered about unreachable nodes.
1851 @item debug @var{level}
1852 Sets debug level to @var{level}.
1855 Forces tinc to try to connect to all uplinks immediately.
1856 Usually tinc attempts to do this itself,
1857 but increases the time it waits between the attempts each time it failed,
1858 and if tinc didn't succeed to connect to an uplink the first time after it started,
1859 it defaults to the maximum time of 15 minutes.
1864 @c ==================================================================
1865 @node Technical information
1866 @chapter Technical information
1871 * The meta-protocol::
1876 @c ==================================================================
1877 @node The connection
1878 @section The connection
1881 Tinc is a daemon that takes VPN data and transmit that to another host
1882 computer over the existing Internet infrastructure.
1886 * The meta-connection::
1890 @c ==================================================================
1891 @node The UDP tunnel
1892 @subsection The UDP tunnel
1894 @cindex virtual network device
1896 The data itself is read from a character device file, the so-called
1897 @emph{virtual network device}. This device is associated with a network
1898 interface. Any data sent to this interface can be read from the device,
1899 and any data written to the device gets sent from the interface.
1900 There are two possible types of virtual network devices:
1901 `tun' style, which are point-to-point devices which can only handle IPv4 and/or IPv6 packets,
1902 and `tap' style, which are Ethernet devices and handle complete Ethernet frames.
1904 So when tinc reads an Ethernet frame from the device, it determines its
1905 type. When tinc is in it's default routing mode, it can handle IPv4 and IPv6
1906 packets. Depending on the Subnet lines, it will send the packets off to their destination IP address.
1907 In the `switch' and `hub' mode, tinc will use broadcasts and MAC address discovery
1908 to deduce the destination of the packets.
1909 Since the latter modes only depend on the link layer information,
1910 any protocol that runs over Ethernet is supported (for instance IPX and Appletalk).
1911 However, only `tap' style devices provide this information.
1913 After the destination has been determined,
1914 the packet will be compressed (optionally),
1915 a sequence number will be added to the packet,
1916 the packet will then be encrypted
1917 and a message authentication code will be appended.
1919 @cindex encapsulating
1921 When that is done, time has come to actually transport the
1922 packet to the destination computer. We do this by sending the packet
1923 over an UDP connection to the destination host. This is called
1924 @emph{encapsulating}, the VPN packet (though now encrypted) is
1925 encapsulated in another IP datagram.
1927 When the destination receives this packet, the same thing happens, only
1928 in reverse. So it checks the message authentication code, decrypts the contents of the UDP datagram,
1929 checks the sequence number
1930 and writes the decrypted information to its own virtual network device.
1932 If the virtual network device is a `tun' device (a point-to-point tunnel),
1933 there is no problem for the kernel to accept a packet.
1934 However, if it is a `tap' device (this is the only available type on FreeBSD),
1935 the destination MAC address must match that of the virtual network interface.
1936 If tinc is in it's default routing mode, ARP does not work, so the correct destination MAC
1937 can not be known by the sending host.
1938 Tinc solves this by letting the receiving end detect the MAC address of its own virtual network interface
1939 and overwriting the destination MAC address of the received packet.
1941 In switch or hub modes ARP does work so the sender already knows the correct destination MAC address.
1942 In those modes every interface should have a unique MAC address, so make sure they are not the same.
1943 Because switch and hub modes rely on MAC addresses to function correctly,
1944 these modes cannot be used on the following operating systems which don't have a `tap' style virtual network device:
1945 OpenBSD, NetBSD, Darwin and Solaris.
1948 @c ==================================================================
1949 @node The meta-connection
1950 @subsection The meta-connection
1952 Having only a UDP connection available is not enough. Though suitable
1953 for transmitting data, we want to be able to reliably send other
1954 information, such as routing and session key information to somebody.
1957 TCP is a better alternative, because it already contains protection
1958 against information being lost, unlike UDP.
1960 So we establish two connections. One for the encrypted VPN data, and one
1961 for other information, the meta-data. Hence, we call the second
1962 connection the meta-connection. We can now be sure that the
1963 meta-information doesn't get lost on the way to another computer.
1965 @cindex data-protocol
1966 @cindex meta-protocol
1967 Like with any communication, we must have a protocol, so that everybody
1968 knows what everything stands for, and how she should react. Because we
1969 have two connections, we also have two protocols. The protocol used for
1970 the UDP data is the ``data-protocol,'' the other one is the
1973 The reason we don't use TCP for both protocols is that UDP is much
1974 better for encapsulation, even while it is less reliable. The real
1975 problem is that when TCP would be used to encapsulate a TCP stream
1976 that's on the private network, for every packet sent there would be
1977 three ACKs sent instead of just one. Furthermore, if there would be
1978 a timeout, both TCP streams would sense the timeout, and both would
1979 start re-sending packets.
1982 @c ==================================================================
1983 @node The meta-protocol
1984 @section The meta-protocol
1986 The meta protocol is used to tie all tinc daemons together, and
1987 exchange information about which tinc daemon serves which virtual
1990 The meta protocol consists of requests that can be sent to the other
1991 side. Each request has a unique number and several parameters. All
1992 requests are represented in the standard ASCII character set. It is
1993 possible to use tools such as telnet or netcat to connect to a tinc
1994 daemon started with the --bypass-security option
1995 and to read and write requests by hand, provided that one
1996 understands the numeric codes sent.
1998 The authentication scheme is described in @ref{Authentication protocol}. After a
1999 successful authentication, the server and the client will exchange all the
2000 information about other tinc daemons and subnets they know of, so that both
2001 sides (and all the other tinc daemons behind them) have their information
2008 ------------------------------------------------------------------
2009 ADD_EDGE node1 node2 21.32.43.54 655 222 0
2010 | | | | | +-> options
2011 | | | | +----> weight
2012 | | | +--------> UDP port of node2
2013 | | +----------------> real address of node2
2014 | +-------------------------> name of destination node
2015 +-------------------------------> name of source node
2017 ADD_SUBNET node 192.168.1.0/24
2018 | | +--> prefixlength
2019 | +--------> network address
2020 +------------------> owner of this subnet
2021 ------------------------------------------------------------------
2024 The ADD_EDGE messages are to inform other tinc daemons that a connection between
2025 two nodes exist. The address of the destination node is available so that
2026 VPN packets can be sent directly to that node.
2028 The ADD_SUBNET messages inform other tinc daemons that certain subnets belong
2029 to certain nodes. tinc will use it to determine to which node a VPN packet has
2036 ------------------------------------------------------------------
2037 DEL_EDGE node1 node2
2038 | +----> name of destination node
2039 +----------> name of source node
2041 DEL_SUBNET node 192.168.1.0/24
2042 | | +--> prefixlength
2043 | +--------> network address
2044 +------------------> owner of this subnet
2045 ------------------------------------------------------------------
2048 In case a connection between two daemons is closed or broken, DEL_EDGE messages
2049 are sent to inform the other daemons of that fact. Each daemon will calculate a
2050 new route to the the daemons, or mark them unreachable if there isn't any.
2057 ------------------------------------------------------------------
2058 REQ_KEY origin destination
2059 | +--> name of the tinc daemon it wants the key from
2060 +----------> name of the daemon that wants the key
2062 ANS_KEY origin destination 4ae0b0a82d6e0078 91 64 4
2063 | | \______________/ | | +--> MAC length
2064 | | | | +-----> digest algorithm
2065 | | | +--------> cipher algorithm
2066 | | +--> 128 bits key
2067 | +--> name of the daemon that wants the key
2068 +----------> name of the daemon that uses this key
2071 +--> daemon that has changed it's packet key
2072 ------------------------------------------------------------------
2075 The keys used to encrypt VPN packets are not sent out directly. This is
2076 because it would generate a lot of traffic on VPNs with many daemons, and
2077 chances are that not every tinc daemon will ever send a packet to every
2078 other daemon. Instead, if a daemon needs a key it sends a request for it
2079 via the meta connection of the nearest hop in the direction of the
2086 ------------------------------------------------------------------
2089 ------------------------------------------------------------------
2092 There is also a mechanism to check if hosts are still alive. Since network
2093 failures or a crash can cause a daemon to be killed without properly
2094 shutting down the TCP connection, this is necessary to keep an up to date
2095 connection list. PINGs are sent at regular intervals, except when there
2096 is also some other traffic. A little bit of salt (random data) is added
2097 with each PING and PONG message, to make sure that long sequences of PING/PONG
2098 messages without any other traffic won't result in known plaintext.
2100 This basically covers what is sent over the meta connection by tinc.
2103 @c ==================================================================
2109 Tinc got its name from ``TINC,'' short for @emph{There Is No Cabal}; the
2110 alleged Cabal was/is an organisation that was said to keep an eye on the
2111 entire Internet. As this is exactly what you @emph{don't} want, we named
2112 the tinc project after TINC.
2115 But in order to be ``immune'' to eavesdropping, you'll have to encrypt
2116 your data. Because tinc is a @emph{Secure} VPN (SVPN) daemon, it does
2117 exactly that: encrypt.
2118 Tinc by default uses blowfish encryption with 128 bit keys in CBC mode, 32 bit
2119 sequence numbers and 4 byte long message authentication codes to make sure
2120 eavesdroppers cannot get and cannot change any information at all from the
2121 packets they can intercept. The encryption algorithm and message authentication
2122 algorithm can be changed in the configuration. The length of the message
2123 authentication codes is also adjustable. The length of the key for the
2124 encryption algorithm is always the default length used by OpenSSL.
2127 * Authentication protocol::
2128 * Encryption of network packets::
2133 @c ==================================================================
2134 @node Authentication protocol
2135 @subsection Authentication protocol
2137 @cindex authentication
2138 A new scheme for authentication in tinc has been devised, which offers some
2139 improvements over the protocol used in 1.0pre2 and 1.0pre3. Explanation is
2149 --------------------------------------------------------------------------
2150 client <attempts connection>
2152 server <accepts connection>
2156 +-------> name of tinc daemon
2160 +-------> name of tinc daemon
2162 client META_KEY 5f0823a93e35b69e...7086ec7866ce582b
2163 \_________________________________/
2164 +-> RSAKEYLEN bits totally random string S1,
2165 encrypted with server's public RSA key
2167 server META_KEY 6ab9c1640388f8f0...45d1a07f8a672630
2168 \_________________________________/
2169 +-> RSAKEYLEN bits totally random string S2,
2170 encrypted with client's public RSA key
2173 - the client will symmetrically encrypt outgoing traffic using S1
2174 - the server will symmetrically encrypt outgoing traffic using S2
2176 client CHALLENGE da02add1817c1920989ba6ae2a49cecbda0
2177 \_________________________________/
2178 +-> CHALLEN bits totally random string H1
2180 server CHALLENGE 57fb4b2ccd70d6bb35a64c142f47e61d57f
2181 \_________________________________/
2182 +-> CHALLEN bits totally random string H2
2184 client CHAL_REPLY 816a86
2185 +-> 160 bits SHA1 of H2
2187 server CHAL_REPLY 928ffe
2188 +-> 160 bits SHA1 of H1
2190 After the correct challenge replies are received, both ends have proved
2191 their identity. Further information is exchanged.
2193 client ACK 655 123 0
2195 | +----> estimated weight
2196 +--------> listening port of client
2198 server ACK 655 321 0
2200 | +----> estimated weight
2201 +--------> listening port of server
2202 --------------------------------------------------------------------------
2205 This new scheme has several improvements, both in efficiency and security.
2207 First of all, the server sends exactly the same kind of messages over the wire
2208 as the client. The previous versions of tinc first authenticated the client,
2209 and then the server. This scheme even allows both sides to send their messages
2210 simultaneously, there is no need to wait for the other to send something first.
2211 This means that any calculations that need to be done upon sending or receiving
2212 a message can also be done in parallel. This is especially important when doing
2213 RSA encryption/decryption. Given that these calculations are the main part of
2214 the CPU time spent for the authentication, speed is improved by a factor 2.
2216 Second, only one RSA encrypted message is sent instead of two. This reduces the
2217 amount of information attackers can see (and thus use for a cryptographic
2218 attack). It also improves speed by a factor two, making the total speedup a
2221 Third, and most important:
2222 The symmetric cipher keys are exchanged first, the challenge is done
2223 afterwards. In the previous authentication scheme, because a man-in-the-middle
2224 could pass the challenge/chal_reply phase (by just copying the messages between
2225 the two real tinc daemons), but no information was exchanged that was really
2226 needed to read the rest of the messages, the challenge/chal_reply phase was of
2227 no real use. The man-in-the-middle was only stopped by the fact that only after
2228 the ACK messages were encrypted with the symmetric cipher. Potentially, it
2229 could even send it's own symmetric key to the server (if it knew the server's
2230 public key) and read some of the metadata the server would send it (it was
2231 impossible for the mitm to read actual network packets though). The new scheme
2232 however prevents this.
2234 This new scheme makes sure that first of all, symmetric keys are exchanged. The
2235 rest of the messages are then encrypted with the symmetric cipher. Then, each
2236 side can only read received messages if they have their private key. The
2237 challenge is there to let the other side know that the private key is really
2238 known, because a challenge reply can only be sent back if the challenge is
2239 decrypted correctly, and that can only be done with knowledge of the private
2242 Fourth: the first thing that is sent via the symmetric cipher encrypted
2243 connection is a totally random string, so that there is no known plaintext (for
2244 an attacker) in the beginning of the encrypted stream.
2247 @c ==================================================================
2248 @node Encryption of network packets
2249 @subsection Encryption of network packets
2252 A data packet can only be sent if the encryption key is known to both
2253 parties, and the connection is activated. If the encryption key is not
2254 known, a request is sent to the destination using the meta connection
2255 to retrieve it. The packet is stored in a queue while waiting for the
2259 The UDP packet containing the network packet from the VPN has the following layout:
2262 ... | IP header | UDP header | seqno | VPN packet | MAC | UDP trailer
2263 \___________________/\_____/
2265 V +---> digest algorithm
2266 Encrypted with symmetric cipher
2269 So, the entire VPN packet is encrypted using a symmetric cipher, including a 32 bits
2270 sequence number that is added in front of the actual VPN packet, to act as a unique
2271 IV for each packet and to prevent replay attacks. A message authentication code
2272 is added to the UDP packet to prevent alteration of packets. By default the
2273 first 4 bytes of the digest are used for this, but this can be changed using
2274 the MACLength configuration variable.
2276 @c ==================================================================
2277 @node Security issues
2278 @subsection Security issues
2280 In August 2000, we discovered the existence of a security hole in all versions
2281 of tinc up to and including 1.0pre2. This had to do with the way we exchanged
2282 keys. Since then, we have been working on a new authentication scheme to make
2283 tinc as secure as possible. The current version uses the OpenSSL library and
2284 uses strong authentication with RSA keys.
2286 On the 29th of December 2001, Jerome Etienne posted a security analysis of tinc
2287 1.0pre4. Due to a lack of sequence numbers and a message authentication code
2288 for each packet, an attacker could possibly disrupt certain network services or
2289 launch a denial of service attack by replaying intercepted packets. The current
2290 version adds sequence numbers and message authentication codes to prevent such
2293 On the 15th of September 2003, Peter Gutmann posted a security analysis of tinc
2294 1.0.1. He argues that the 32 bit sequence number used by tinc is not a good IV,
2295 that tinc's default length of 4 bytes for the MAC is too short, and he doesn't
2296 like tinc's use of RSA during authentication. We do not know of a security hole
2297 in this version of tinc, but tinc's security is not as strong as TLS or IPsec.
2298 We will address these issues in tinc 2.0.
2300 Cryptography is a hard thing to get right. We cannot make any
2301 guarantees. Time, review and feedback are the only things that can
2302 prove the security of any cryptographic product. If you wish to review
2303 tinc or give us feedback, you are stronly encouraged to do so.
2306 @c ==================================================================
2307 @node Platform specific information
2308 @chapter Platform specific information
2311 * Interface configuration::
2315 @c ==================================================================
2316 @node Interface configuration
2317 @section Interface configuration
2319 When configuring an interface, one normally assigns it an address and a
2320 netmask. The address uniquely identifies the host on the network attached to
2321 the interface. The netmask, combined with the address, forms a subnet. It is
2322 used to add a route to the routing table instructing the kernel to send all
2323 packets which fall into that subnet to that interface. Because all packets for
2324 the entire VPN should go to the virtual network interface used by tinc, the
2325 netmask should be such that it encompasses the entire VPN.
2329 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2331 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2332 @item Linux iproute2
2333 @tab @code{ip addr add} @var{address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2335 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2337 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2339 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2341 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2342 @item Darwin (MacOS/X)
2343 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2345 @tab @code{netsh interface ip set address} @var{interface} @code{static} @var{address} @var{netmask}
2351 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2353 @tab @code{ifconfig} @var{interface} @code{add} @var{address}@code{/}@var{prefixlength}
2355 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2357 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2359 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2361 @tab @code{ifconfig} @var{interface} @code{inet6 plumb up}
2363 @tab @code{ifconfig} @var{interface} @code{inet6 addif} @var{address} @var{address}
2364 @item Darwin (MacOS/X)
2365 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2367 @tab @code{netsh interface ipv6 add address} @var{interface} @code{static} @var{address}/@var{prefixlength}
2371 @c ==================================================================
2375 In some cases it might be necessary to add more routes to the virtual network
2376 interface. There are two ways to indicate which interface a packet should go
2377 to, one is to use the name of the interface itself, another way is to specify
2378 the (local) address that is assigned to that interface (@var{local_address}). The
2379 former way is unambiguous and therefore preferable, but not all platforms
2382 Adding routes to IPv4 subnets:
2384 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2386 @tab @code{route add -net} @var{network_address} @code{netmask} @var{netmask} @var{interface}
2387 @item Linux iproute2
2388 @tab @code{ip route add} @var{network_address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2390 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2392 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2394 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2396 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address} @code{-interface}
2397 @item Darwin (MacOS/X)
2398 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2400 @tab @code{netsh routing ip add persistentroute} @var{network_address} @var{netmask} @var{interface} @var{local_address}
2403 Adding routes to IPv6 subnets:
2405 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2407 @tab @code{route add -A inet6} @var{network_address}@code{/}@var{prefixlength} @var{interface}
2408 @item Linux iproute2
2409 @tab @code{ip route add} @var{network_address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2411 @tab @code{route add -inet6} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2413 @tab @code{route add -inet6} @var{network_address} @var{local_address} @code{-prefixlen} @var{prefixlength}
2415 @tab @code{route add -inet6} @var{network_address} @var{local_address} @code{-prefixlen} @var{prefixlength}
2417 @tab @code{route add -inet6} @var{network_address}@code{/}@var{prefixlength} @var{local_address} @code{-interface}
2418 @item Darwin (MacOS/X)
2421 @tab @code{netsh interface ipv6 add route} @var{network address}/@var{prefixlength} @var{interface}
2425 @c ==================================================================
2431 * Contact information::
2436 @c ==================================================================
2437 @node Contact information
2438 @section Contact information
2441 Tinc's website is at @url{http://www.tinc-vpn.org/},
2442 this server is located in the Netherlands.
2445 We have an IRC channel on the FreeNode and OFTC IRC networks. Connect to
2446 @uref{http://www.freenode.net/, irc.freenode.net}
2448 @uref{http://www.oftc.net/, irc.oftc.net}
2449 and join channel #tinc.
2452 @c ==================================================================
2457 @item Ivo Timmermans (zarq)
2458 @item Guus Sliepen (guus) (@email{guus@@tinc-vpn.org})
2461 We have received a lot of valuable input from users. With their help,
2462 tinc has become the flexible and robust tool that it is today. We have
2463 composed a list of contributions, in the file called @file{THANKS} in
2464 the source distribution.
2467 @c ==================================================================
2469 @unnumbered Concept Index
2471 @c ==================================================================
2475 @c ==================================================================