1 \input texinfo @c -*-texinfo-*-
9 @include tincinclude.texi
12 @dircategory Networking tools
14 * tinc: (tinc). The tinc Manual.
17 This is the info manual for @value{PACKAGE} version @value{VERSION}, a Virtual Private Network daemon.
19 Copyright @copyright{} 1998-2006 Ivo Timmermans,
20 Guus Sliepen <guus@@tinc-vpn.org> and
21 Wessel Dankers <wsl@@tinc-vpn.org>.
25 Permission is granted to make and distribute verbatim copies of this
26 manual provided the copyright notice and this permission notice are
27 preserved on all copies.
29 Permission is granted to copy and distribute modified versions of this
30 manual under the conditions for verbatim copying, provided that the
31 entire resulting derived work is distributed under the terms of a
32 permission notice identical to this one.
38 @subtitle Setting up a Virtual Private Network with tinc
39 @author Ivo Timmermans and Guus Sliepen
42 @vskip 0pt plus 1filll
44 This is the info manual for @value{PACKAGE} version @value{VERSION}, a Virtual Private Network daemon.
46 Copyright @copyright{} 1998-2007 Ivo Timmermans,
47 Guus Sliepen <guus@@tinc-vpn.org> and
48 Wessel Dankers <wsl@@tinc-vpn.org>.
52 Permission is granted to make and distribute verbatim copies of this
53 manual provided the copyright notice and this permission notice are
54 preserved on all copies.
56 Permission is granted to copy and distribute modified versions of this
57 manual under the conditions for verbatim copying, provided that the
58 entire resulting derived work is distributed under the terms of a
59 permission notice identical to this one.
64 @c ==================================================================
75 * Technical information::
76 * Platform specific information::
78 * Concept Index:: All used terms explained
82 @c ==================================================================
87 Tinc is a Virtual Private Network (VPN) daemon that uses tunneling and
88 encryption to create a secure private network between hosts on the
91 Because the tunnel appears to the IP level network code as a normal
92 network device, there is no need to adapt any existing software.
93 The encrypted tunnels allows VPN sites to share information with each other
94 over the Internet without exposing any information to others.
96 This document is the manual for tinc. Included are chapters on how to
97 configure your computer to use tinc, as well as the configuration
98 process of tinc itself.
101 * Virtual Private Networks::
103 * Supported platforms::
106 @c ==================================================================
107 @node Virtual Private Networks
108 @section Virtual Private Networks
111 A Virtual Private Network or VPN is a network that can only be accessed
112 by a few elected computers that participate. This goal is achievable in
113 more than just one way.
116 Private networks can consist of a single stand-alone Ethernet LAN. Or
117 even two computers hooked up using a null-modem cable. In these cases,
119 obvious that the network is @emph{private}, no one can access it from the
120 outside. But if your computers are linked to the Internet, the network
121 is not private anymore, unless one uses firewalls to block all private
122 traffic. But then, there is no way to send private data to trusted
123 computers on the other end of the Internet.
126 This problem can be solved by using @emph{virtual} networks. Virtual
127 networks can live on top of other networks, but they use encapsulation to
128 keep using their private address space so they do not interfere with
129 the Internet. Mostly, virtual networks appear like a singe LAN, even though
130 they can span the entire world. But virtual networks can't be secured
131 by using firewalls, because the traffic that flows through it has to go
132 through the Internet, where other people can look at it.
134 As is the case with either type of VPN, anybody could eavesdrop. Or
135 worse, alter data. Hence it's probably advisable to encrypt the data
136 that flows over the network.
138 When one introduces encryption, we can form a true VPN. Other people may
139 see encrypted traffic, but if they don't know how to decipher it (they
140 need to know the key for that), they cannot read the information that flows
141 through the VPN. This is what tinc was made for.
144 @c ==================================================================
149 I really don't quite remember what got us started, but it must have been
150 Guus' idea. He wrote a simple implementation (about 50 lines of C) that
151 used the ethertap device that Linux knows of since somewhere
152 about kernel 2.1.60. It didn't work immediately and he improved it a
153 bit. At this stage, the project was still simply called "vpnd".
155 Since then, a lot has changed---to say the least.
158 Tinc now supports encryption, it consists of a single daemon (tincd) for
159 both the receiving and sending end, it has become largely
160 runtime-configurable---in short, it has become a full-fledged
161 professional package.
163 @cindex traditional VPNs
165 Tinc also allows more than two sites to connect to eachother and form a single VPN.
166 Traditionally VPNs are created by making tunnels, which only have two endpoints.
167 Larger VPNs with more sites are created by adding more tunnels.
168 Tinc takes another approach: only endpoints are specified,
169 the software itself will take care of creating the tunnels.
170 This allows for easier configuration and improved scalability.
172 A lot can---and will be---changed. We have a number of things that we would like to
173 see in the future releases of tinc. Not everything will be available in
174 the near future. Our first objective is to make tinc work perfectly as
175 it stands, and then add more advanced features.
177 Meanwhile, we're always open-minded towards new ideas. And we're
181 @c ==================================================================
182 @node Supported platforms
183 @section Supported platforms
186 Tinc has been verified to work under Linux, FreeBSD, OpenBSD, NetBSD, MacOS/X (Darwin), Solaris, and Windows (both natively and in a Cygwin environment),
187 with various hardware architectures. These are some of the platforms
188 that are supported by the universal tun/tap device driver or other virtual network device drivers.
189 Without such a driver, tinc will most
190 likely compile and run, but it will not be able to send or receive data
194 For an up to date list of supported platforms, please check the list on
196 @uref{http://www.tinc-vpn.org/platforms}.
204 @c Preparing your system
211 @c ==================================================================
213 @chapter Preparations
215 This chapter contains information on how to prepare your system to
219 * Configuring the kernel::
224 @c ==================================================================
225 @node Configuring the kernel
226 @section Configuring the kernel
229 * Configuration of Linux kernels 2.1.60 up to 2.4.0::
230 * Configuration of Linux kernels 2.4.0 and higher::
231 * Configuration of FreeBSD kernels::
232 * Configuration of OpenBSD kernels::
233 * Configuration of NetBSD kernels::
234 * Configuration of Solaris kernels::
235 * Configuration of Darwin (MacOS/X) kernels::
236 * Configuration of Windows::
240 @c ==================================================================
241 @node Configuration of Linux kernels 2.1.60 up to 2.4.0
242 @subsection Configuration of Linux kernels 2.1.60 up to 2.4.0
245 For kernels up to 2.4.0, you need a kernel that supports the ethertap device.
246 Most distributions come with kernels that already support this.
247 If not, here are the options you have to turn on when configuring a new kernel:
250 Code maturity level options
251 [*] Prompt for development and/or incomplete code/drivers
253 [*] Kernel/User netlink socket
254 <M> Netlink device emulation
255 Network device support
256 <M> Ethertap network tap
259 If you want to run more than one instance of tinc or other programs that use
260 the ethertap, you have to compile the ethertap driver as a module, otherwise
261 you can also choose to compile it directly into the kernel.
263 If you decide to build any of these as dynamic kernel modules, it's a good idea
264 to add these lines to @file{/etc/modules.conf}:
267 alias char-major-36 netlink_dev
269 options tap0 -o tap0 unit=0
271 options tap1 -o tap1 unit=1
273 alias tap@emph{N} ethertap
274 options tap@emph{N} -o tap@emph{N} unit=@emph{N}
277 Add as much alias/options lines as necessary.
280 @c ==================================================================
281 @node Configuration of Linux kernels 2.4.0 and higher
282 @subsection Configuration of Linux kernels 2.4.0 and higher
284 @cindex Universal tun/tap
285 For kernels 2.4.0 and higher, you need a kernel that supports the Universal tun/tap device.
286 Most distributions come with kernels that already support this.
287 Here are the options you have to turn on when configuring a new kernel:
290 Code maturity level options
291 [*] Prompt for development and/or incomplete code/drivers
292 Network device support
293 <M> Universal tun/tap device driver support
296 It's not necessary to compile this driver as a module, even if you are going to
297 run more than one instance of tinc.
299 If you have an early 2.4 kernel, you can choose both the tun/tap driver and the
300 `Ethertap network tap' device. This latter is marked obsolete, and chances are
301 that it won't even function correctly anymore. Make sure you select the
302 universal tun/tap driver.
304 If you decide to build the tun/tap driver as a kernel module, add these lines
305 to @file{/etc/modules.conf}:
308 alias char-major-10-200 tun
312 @c ==================================================================
313 @node Configuration of FreeBSD kernels
314 @subsection Configuration of FreeBSD kernels
316 For FreeBSD version 4.1 and higher, tun and tap drivers are included in the default kernel configuration.
317 Using tap devices is recommended.
320 @c ==================================================================
321 @node Configuration of OpenBSD kernels
322 @subsection Configuration of OpenBSD kernels
324 For OpenBSD version 2.9 and higher,
325 the tun driver is included in the default kernel configuration.
326 There is also a kernel patch from @uref{http://diehard.n-r-g.com/stuff/openbsd/}
327 which adds a tap device to OpenBSD.
328 This should work with tinc.
331 @c ==================================================================
332 @node Configuration of NetBSD kernels
333 @subsection Configuration of NetBSD kernels
335 For NetBSD version 1.5.2 and higher,
336 the tun driver is included in the default kernel configuration.
338 Tunneling IPv6 may not work on NetBSD's tun device.
341 @c ==================================================================
342 @node Configuration of Solaris kernels
343 @subsection Configuration of Solaris kernels
345 For Solaris 8 (SunOS 5.8) and higher,
346 the tun driver may or may not be included in the default kernel configuration.
347 If it isn't, the source can be downloaded from @uref{http://vtun.sourceforge.net/tun/}.
348 For x86 and sparc64 architectures, precompiled versions can be found at @uref{http://www.monkey.org/~dugsong/fragroute/}.
349 If the @file{net/if_tun.h} header file is missing, install it from the source package.
352 @c ==================================================================
353 @node Configuration of Darwin (MacOS/X) kernels
354 @subsection Configuration of Darwin (MacOS/X) kernels
356 Tinc on Darwin relies on a tunnel driver for its data acquisition from the kernel.
357 Tinc supports either the driver from @uref{http://www-user.rhrk.uni-kl.de/~nissler/tuntap/},
358 which supports both tun and tap style devices,
359 and also the driver from from @uref{http://chrisp.de/en/projects/tunnel.html}.
360 The former driver is recommended.
361 The tunnel driver must be loaded before starting tinc with the following command:
368 @c ==================================================================
369 @node Configuration of Windows
370 @subsection Configuration of Windows
372 You will need to install the latest TAP-Win32 driver from OpenVPN.
373 You can download it from @uref{http://openvpn.sourceforge.net}.
374 Using the Network Connections control panel,
375 configure the TAP-Win32 network interface in the same way as you would do from the tinc-up script,
376 as explained in the rest of the documentation.
379 @c ==================================================================
385 Before you can configure or build tinc, you need to have the OpenSSL,
386 zlib and lzo libraries installed on your system. If you try to configure tinc without
387 having them installed, configure will give you an error message, and stop.
397 @c ==================================================================
402 For all cryptography-related functions, tinc uses the functions provided
403 by the OpenSSL library.
405 If this library is not installed, you wil get an error when configuring
406 tinc for build. Support for running tinc without having OpenSSL
407 installed @emph{may} be added in the future.
409 You can use your operating system's package manager to install this if
410 available. Make sure you install the development AND runtime versions
413 If you have to install OpenSSL manually, you can get the source code
414 from @url{http://www.openssl.org/}. Instructions on how to configure,
415 build and install this package are included within the package. Please
416 make sure you build development and runtime libraries (which is the
419 If you installed the OpenSSL libraries from source, it may be necessary
420 to let configure know where they are, by passing configure one of the
421 --with-openssl-* parameters.
424 --with-openssl=DIR OpenSSL library and headers prefix
425 --with-openssl-include=DIR OpenSSL headers directory
426 (Default is OPENSSL_DIR/include)
427 --with-openssl-lib=DIR OpenSSL library directory
428 (Default is OPENSSL_DIR/lib)
432 @subsubheading License
435 The complete source code of tinc is covered by the GNU GPL version 2.
436 Since the license under which OpenSSL is distributed is not directly
437 compatible with the terms of the GNU GPL
438 @uref{http://www.openssl.org/support/faq.html#LEGAL2}, we
439 include an exemption to the GPL (see also the file COPYING.README) to allow
440 everyone to create a statically or dynamically linked executable:
443 This program is released under the GPL with the additional exemption
444 that compiling, linking, and/or using OpenSSL is allowed. You may
445 provide binary packages linked to the OpenSSL libraries, provided that
446 all other requirements of the GPL are met.
449 Since the LZO library used by tinc is also covered by the GPL,
450 we also present the following exemption:
453 Hereby I grant a special exception to the tinc VPN project
454 (http://www.tinc-vpn.org/) to link the LZO library with the OpenSSL library
455 (http://www.openssl.org).
457 Markus F.X.J. Oberhumer
461 @c ==================================================================
466 For the optional compression of UDP packets, tinc uses the functions provided
469 If this library is not installed, you wil get an error when configuring
470 tinc for build. Support for running tinc without having zlib
471 installed @emph{may} be added in the future.
473 You can use your operating system's package manager to install this if
474 available. Make sure you install the development AND runtime versions
477 If you have to install zlib manually, you can get the source code
478 from @url{http://www.gzip.org/zlib/}. Instructions on how to configure,
479 build and install this package are included within the package. Please
480 make sure you build development and runtime libraries (which is the
484 @c ==================================================================
489 Another form of compression is offered using the lzo library.
491 If this library is not installed, you wil get an error when configuring
492 tinc for build. Support for running tinc without having lzo
493 installed @emph{may} be added in the future.
495 You can use your operating system's package manager to install this if
496 available. Make sure you install the development AND runtime versions
499 If you have to install lzo manually, you can get the source code
500 from @url{http://www.oberhumer.com/opensource/lzo/}. Instructions on how to configure,
501 build and install this package are included within the package. Please
502 make sure you build development and runtime libraries (which is the
506 @c ==================================================================
511 For the main event loop, tinc uses the libevent library.
513 If this library is not installed, you wil get an error when configuring
516 You can use your operating system's package manager to install this if
517 available. Make sure you install the development AND runtime versions
520 If you have to install libevent manually, you can get the source code
521 from @url{http://monkey.org/~provos/libevent/}. Instructions on how to configure,
522 build and install this package are included within the package. Please
523 make sure you build development and runtime libraries (which is the
536 @c ==================================================================
538 @chapter Installation
540 If you use Debian, you may want to install one of the
541 precompiled packages for your system. These packages are equipped with
542 system startup scripts and sample configurations.
544 If you cannot use one of the precompiled packages, or you want to compile tinc
545 for yourself, you can use the source. The source is distributed under
546 the GNU General Public License (GPL). Download the source from the
547 @uref{http://www.tinc-vpn.org/download, download page}, which has
548 the checksums of these files listed; you may wish to check these with
549 md5sum before continuing.
551 Tinc comes in a convenient autoconf/automake package, which you can just
552 treat the same as any other package. Which is just untar it, type
553 `./configure' and then `make'.
554 More detailed instructions are in the file @file{INSTALL}, which is
555 included in the source distribution.
558 * Building and installing tinc::
563 @c ==================================================================
564 @node Building and installing tinc
565 @section Building and installing tinc
567 Detailed instructions on configuring the source, building tinc and installing tinc
568 can be found in the file called @file{INSTALL}.
570 @cindex binary package
571 If you happen to have a binary package for tinc for your distribution,
572 you can use the package management tools of that distribution to install tinc.
573 The documentation that comes along with your distribution will tell you how to do that.
576 * Darwin (MacOS/X) build environment::
577 * Cygwin (Windows) build environment::
578 * MinGW (Windows) build environment::
582 @c ==================================================================
583 @node Darwin (MacOS/X) build environment
584 @subsection Darwin (MacOS/X) build environment
586 In order to build tinc on Darwin, you need to install the MacOS/X Developer Tools
587 from @uref{http://developer.apple.com/tools/macosxtools.html} and
588 a recent version of Fink from @uref{http://fink.sourceforge.net/}.
590 After installation use fink to download and install the following packages:
591 autoconf25, automake, dlcompat, m4, openssl, zlib and lzo.
593 @c ==================================================================
594 @node Cygwin (Windows) build environment
595 @subsection Cygwin (Windows) build environment
597 If Cygwin hasn't already been installed, install it directly from
598 @uref{http://www.cygwin.com/}.
600 When tinc is compiled in a Cygwin environment, it can only be run in this environment,
601 but all programs, including those started outside the Cygwin environment, will be able to use the VPN.
602 It will also support all features.
604 @c ==================================================================
605 @node MinGW (Windows) build environment
606 @subsection MinGW (Windows) build environment
608 You will need to install the MinGW environment from @uref{http://www.mingw.org}.
610 When tinc is compiled using MinGW it runs natively under Windows,
611 it is not necessary to keep MinGW installed.
613 When detaching, tinc will install itself as a service,
614 which will be restarted automatically after reboots.
617 @c ==================================================================
619 @section System files
621 Before you can run tinc, you must make sure you have all the needed
622 files on your system.
630 @c ==================================================================
632 @subsection Device files
635 First, you'll need the special device file(s) that form the interface
636 between the kernel and the daemon.
638 The permissions for these files have to be such that only the super user
639 may read/write to this file. You'd want this, because otherwise
640 eavesdropping would become a bit too easy. This does, however, imply
641 that you'd have to run tincd as root.
643 If you use Linux and have a kernel version prior to 2.4.0, you have to make the
647 mknod -m 600 /dev/tap0 c 36 16
648 mknod -m 600 /dev/tap1 c 36 17
650 mknod -m 600 /dev/tap@emph{N} c 36 @emph{N+16}
653 There is a maximum of 16 ethertap devices.
655 If you use the universal tun/tap driver, you have to create the
656 following device file (unless it already exist):
659 mknod -m 600 /dev/tun c 10 200
662 If you use Linux, and you run the new 2.4 kernel using the devfs filesystem,
663 then the tun/tap device will probably be automatically generated as
666 Unlike the ethertap device, you do not need multiple device files if
667 you are planning to run multiple tinc daemons.
670 @c ==================================================================
672 @subsection Other files
674 @subsubheading @file{/etc/networks}
676 You may add a line to @file{/etc/networks} so that your VPN will get a
677 symbolic name. For example:
683 @subsubheading @file{/etc/services}
686 You may add this line to @file{/etc/services}. The effect is that you
687 may supply a @samp{tinc} as a valid port number to some programs. The
688 number 655 is registered with the IANA.
693 # Ivo Timmermans <ivo@@tinc-vpn.org>
708 @c ==================================================================
710 @chapter Configuration
713 * Configuration introduction::
714 * Multiple networks::
715 * How connections work::
716 * Configuration files::
717 * Generating keypairs::
718 * Network interfaces::
719 * Example configuration::
722 @c ==================================================================
723 @node Configuration introduction
724 @section Configuration introduction
726 Before actually starting to configure tinc and editing files,
727 make sure you have read this entire section so you know what to expect.
728 Then, make it clear to yourself how you want to organize your VPN:
729 What are the nodes (computers running tinc)?
730 What IP addresses/subnets do they have?
731 What is the network mask of the entire VPN?
732 Do you need special firewall rules?
733 Do you have to set up masquerading or forwarding rules?
734 Do you want to run tinc in router mode or switch mode?
735 These questions can only be answered by yourself,
736 you will not find the answers in this documentation.
737 Make sure you have an adequate understanding of networks in general.
738 @cindex Network Administrators Guide
739 A good resource on networking is the
740 @uref{http://www.linuxdoc.org/LDP/nag2/, Linux Network Administrators Guide}.
742 If you have everything clearly pictured in your mind,
743 proceed in the following order:
744 First, generate the configuration files (@file{tinc.conf}, your host configuration file, @file{tinc-up} and perhaps @file{tinc-down}).
745 Then generate the keypairs.
746 Finally, distribute the host configuration files.
747 These steps are described in the subsections below.
750 @c ==================================================================
751 @node Multiple networks
752 @section Multiple networks
754 @cindex multiple networks
756 In order to allow you to run more than one tinc daemon on one computer,
757 for instance if your computer is part of more than one VPN,
758 you can assign a @var{netname} to your VPN.
759 It is not required if you only run one tinc daemon,
760 it doesn't even have to be the same on all the sites of your VPN,
761 but it is recommended that you choose one anyway.
763 We will asume you use a netname throughout this document.
764 This means that you call tincd with the -n argument,
765 which will assign a netname to this daemon.
767 The effect of this is that the daemon will set its configuration
768 root to @file{@value{sysconfdir}/tinc/@var{netname}/}, where @var{netname} is your argument to the -n
769 option. You'll notice that it appears in syslog as @file{tinc.@var{netname}}.
771 However, it is not strictly necessary that you call tinc with the -n
772 option. In this case, the network name would just be empty, and it will
773 be used as such. tinc now looks for files in @file{@value{sysconfdir}/tinc/}, instead of
774 @file{@value{sysconfdir}/tinc/@var{netname}/}; the configuration file should be @file{@value{sysconfdir}/tinc/tinc.conf},
775 and the host configuration files are now expected to be in @file{@value{sysconfdir}/tinc/hosts/}.
777 But it is highly recommended that you use this feature of tinc, because
778 it will be so much clearer whom your daemon talks to. Hence, we will
779 assume that you use it.
782 @c ==================================================================
783 @node How connections work
784 @section How connections work
786 When tinc starts up, it parses the command-line options and then
787 reads in the configuration file tinc.conf.
788 If it sees one or more `ConnectTo' values pointing to other tinc daemons in that file,
789 it will try to connect to those other daemons.
790 Whether this succeeds or not and whether `ConnectTo' is specified or not,
791 tinc will listen for incoming connection from other deamons.
792 If you did specify a `ConnectTo' value and the other side is not responding,
793 tinc will keep retrying.
794 This means that once started, tinc will stay running until you tell it to stop,
795 and failures to connect to other tinc daemons will not stop your tinc daemon
796 for trying again later.
797 This means you don't have to intervene if there are temporary network problems.
801 There is no real distinction between a server and a client in tinc.
802 If you wish, you can view a tinc daemon without a `ConnectTo' value as a server,
803 and one which does specify such a value as a client.
804 It does not matter if two tinc daemons have a `ConnectTo' value pointing to each other however.
807 @c ==================================================================
808 @node Configuration files
809 @section Configuration files
811 The actual configuration of the daemon is done in the file
812 @file{@value{sysconfdir}/tinc/@var{netname}/tinc.conf} and at least one other file in the directory
813 @file{@value{sysconfdir}/tinc/@var{netname}/hosts/}.
815 These file consists of comments (lines started with a #) or assignments
822 The variable names are case insensitive, and any spaces, tabs, newlines
823 and carriage returns are ignored. Note: it is not required that you put
824 in the `=' sign, but doing so improves readability. If you leave it
825 out, remember to replace it with at least one space character.
827 In this section all valid variables are listed in alphabetical order.
828 The default value is given between parentheses,
829 other comments are between square brackets.
832 * Main configuration variables::
833 * Host configuration variables::
839 @c ==================================================================
840 @node Main configuration variables
841 @subsection Main configuration variables
844 @cindex AddressFamily
845 @item AddressFamily = <ipv4|ipv6|any> (any)
846 This option affects the address family of listening and outgoing sockets.
847 If any is selected, then depending on the operating system
848 both IPv4 and IPv6 or just IPv6 listening sockets will be created.
850 @cindex BindToAddress
851 @item BindToAddress = <@var{address}> [experimental]
852 If your computer has more than one IPv4 or IPv6 address, tinc
853 will by default listen on all of them for incoming connections.
854 It is possible to bind only to a single address with this variable.
856 This option may not work on all platforms.
858 @cindex BindToInterface
859 @item BindToInterface = <@var{interface}> [experimental]
860 If you have more than one network interface in your computer, tinc will
861 by default listen on all of them for incoming connections. It is
862 possible to bind tinc to a single interface like eth0 or ppp0 with this
865 This option may not work on all platforms.
868 @item ConnectTo = <@var{name}>
869 Specifies which other tinc daemon to connect to on startup.
870 Multiple ConnectTo variables may be specified,
871 in which case outgoing connections to each specified tinc daemon are made.
872 The names should be known to this tinc daemon
873 (i.e., there should be a host configuration file for the name on the ConnectTo line).
875 If you don't specify a host with ConnectTo,
876 tinc won't try to connect to other daemons at all,
877 and will instead just listen for incoming connections.
880 @item Device = <@var{device}> (@file{/dev/tap0}, @file{/dev/net/tun} or other depending on platform)
881 The virtual network device to use.
882 Tinc will automatically detect what kind of device it is.
883 Note that you can only use one device per daemon.
884 Under Windows, use @var{Interface} instead of @var{Device}.
885 Note that you can only use one device per daemon.
886 See also @ref{Device files}.
889 @item Hostnames = <yes|no> (no)
890 This option selects whether IP addresses (both real and on the VPN)
891 should be resolved. Since DNS lookups are blocking, it might affect
892 tinc's efficiency, even stopping the daemon for a few seconds everytime
893 it does a lookup if your DNS server is not responding.
895 This does not affect resolving hostnames to IP addresses from the
899 @item Interface = <@var{interface}>
900 Defines the name of the interface corresponding to the virtual network device.
901 Depending on the operating system and the type of device this may or may not actually set the name of the interface.
902 Under Windows, this variable is used to select which network interface will be used.
903 If you specified a Device, this variable is almost always already correctly set.
906 @item Mode = <router|switch|hub> (router)
907 This option selects the way packets are routed to other daemons.
913 variables in the host configuration files will be used to form a routing table.
914 Only unicast packets of routable protocols (IPv4 and IPv6) are supported in this mode.
916 This is the default mode, and unless you really know you need another mode, don't change it.
920 In this mode the MAC addresses of the packets on the VPN will be used to
921 dynamically create a routing table just like an Ethernet switch does.
922 Unicast, multicast and broadcast packets of every protocol that runs over Ethernet are supported in this mode
923 at the cost of frequent broadcast ARP requests and routing table updates.
925 This mode is primarily useful if you want to bridge Ethernet segments.
929 This mode is almost the same as the switch mode, but instead
930 every packet will be broadcast to the other daemons
931 while no routing table is managed.
935 @item KeyExpire = <@var{seconds}> (3600)
936 This option controls the time the encryption keys used to encrypt the data
937 are valid. It is common practice to change keys at regular intervals to
938 make it even harder for crackers, even though it is thought to be nearly
939 impossible to crack a single key.
942 @item MACExpire = <@var{seconds}> (600)
943 This option controls the amount of time MAC addresses are kept before they are removed.
944 This only has effect when Mode is set to "switch".
947 @item Name = <@var{name}> [required]
948 This is a symbolic name for this connection. It can be anything
951 @item PingInterval = <@var{seconds}> (60)
952 The number of seconds of inactivity that tinc will wait before sending a
953 probe to the other end.
956 @item PingTimeout = <@var{seconds}> (5)
957 The number of seconds to wait for a response to pings or to allow meta
958 connections to block. If the other end doesn't respond within this time,
959 the connection is terminated, and the others will be notified of this.
961 @cindex PriorityInheritance
962 @item PriorityInheritance = <yes|no> (no) [experimental]
963 When this option is enabled the value of the TOS field of tunneled IPv4 packets
964 will be inherited by the UDP packets that are sent out.
967 @item PrivateKey = <@var{key}> [obsolete]
968 This is the RSA private key for tinc. However, for safety reasons it is
969 advised to store private keys of any kind in separate files. This prevents
970 accidental eavesdropping if you are editting the configuration file.
972 @cindex PrivateKeyFile
973 @item PrivateKeyFile = <@var{path}> (@file{@value{sysconfdir}/tinc/@var{netname}/rsa_key.priv})
974 This is the full path name of the RSA private key file that was
975 generated by @samp{tincctl generate-keys}. It must be a full path, not a
978 Note that there must be exactly one of PrivateKey
980 specified in the configuration file.
983 @item TunnelServer = <yes|no> (no) [experimental]
984 When this option is enabled tinc will no longer forward information between other tinc daemons,
985 and will only allow nodes and subnets on the VPN which are present in the
986 @file{@value{sysconfdir}/tinc/@var{netname}/hosts/} directory.
991 @c ==================================================================
992 @node Host configuration variables
993 @subsection Host configuration variables
997 @item Address = <@var{IP address}|@var{hostname}> [recommended]
998 This variable is only required if you want to connect to this host. It
999 must resolve to the external IP address where the host can be reached,
1000 not the one that is internal to the VPN.
1003 @item Cipher = <@var{cipher}> (blowfish)
1004 The symmetric cipher algorithm used to encrypt UDP packets.
1005 Any cipher supported by OpenSSL is recognized.
1006 Furthermore, specifying "none" will turn off packet encryption.
1007 It is best to use only those ciphers which support CBC mode.
1010 @item Compression = <@var{level}> (0)
1011 This option sets the level of compression used for UDP packets.
1012 Possible values are 0 (off), 1 (fast zlib) and any integer up to 9 (best zlib),
1013 10 (fast lzo) and 11 (best lzo).
1016 @item Digest = <@var{digest}> (sha1)
1017 The digest algorithm used to authenticate UDP packets.
1018 Any digest supported by OpenSSL is recognized.
1019 Furthermore, specifying "none" will turn off packet authentication.
1021 @cindex IndirectData
1022 @item IndirectData = <yes|no> (no)
1023 This option specifies whether other tinc daemons besides the one you
1024 specified with ConnectTo can make a direct connection to you. This is
1025 especially useful if you are behind a firewall and it is impossible to
1026 make a connection from the outside to your tinc daemon. Otherwise, it
1027 is best to leave this option out or set it to no.
1030 @item MACLength = <@var{bytes}> (4)
1031 The length of the message authentication code used to authenticate UDP packets.
1032 Can be anything from 0
1033 up to the length of the digest produced by the digest algorithm.
1036 @item Port = <@var{port}> (655)
1037 This is the port this tinc daemon listens on.
1038 You can use decimal portnumbers or symbolic names (as listed in @file{/etc/services}).
1041 @item PublicKey = <@var{key}> [obsolete]
1042 This is the RSA public key for this host.
1044 @cindex PublicKeyFile
1045 @item PublicKeyFile = <@var{path}> [obsolete]
1046 This is the full path name of the RSA public key file that was generated
1047 by @samp{tincctl generate-keys}. It must be a full path, not a relative
1051 From version 1.0pre4 on tinc will store the public key directly into the
1052 host configuration file in PEM format, the above two options then are not
1053 necessary. Either the PEM format is used, or exactly
1054 @strong{one of the above two options} must be specified
1055 in each host configuration file, if you want to be able to establish a
1056 connection with that host.
1059 @item Subnet = <@var{address}[/@var{prefixlength}]>
1060 The subnet which this tinc daemon will serve.
1061 Tinc tries to look up which other daemon it should send a packet to by searching the appropiate subnet.
1062 If the packet matches a subnet,
1063 it will be sent to the daemon who has this subnet in his host configuration file.
1064 Multiple subnet lines can be specified for each daemon.
1066 Subnets can either be single MAC, IPv4 or IPv6 addresses,
1067 in which case a subnet consisting of only that single address is assumed,
1068 or they can be a IPv4 or IPv6 network address with a prefixlength.
1069 Shorthand notations are not supported.
1070 For example, IPv4 subnets must be in a form like 192.168.1.0/24,
1071 where 192.168.1.0 is the network address and 24 is the number of bits set in the netmask.
1072 Note that subnets like 192.168.1.1/24 are invalid!
1073 Read a networking HOWTO/FAQ/guide if you don't understand this.
1074 IPv6 subnets are notated like fec0:0:0:1:0:0:0:0/64.
1075 MAC addresses are notated like 0:1a:2b:3c:4d:5e.
1077 @cindex CIDR notation
1078 Prefixlength is the number of bits set to 1 in the netmask part; for
1079 example: netmask 255.255.255.0 would become /24, 255.255.252.0 becomes
1080 /22. This conforms to standard CIDR notation as described in
1081 @uref{ftp://ftp.isi.edu/in-notes/rfc1519.txt, RFC1519}
1084 @item TCPonly = <yes|no> (no) [experimental]
1085 If this variable is set to yes, then the packets are tunnelled over a
1086 TCP connection instead of a UDP connection. This is especially useful
1087 for those who want to run a tinc daemon from behind a masquerading
1088 firewall, or if UDP packet routing is disabled somehow.
1089 Setting this options also implicitly sets IndirectData.
1093 @c ==================================================================
1098 Apart from reading the server and host configuration files,
1099 tinc can also run scripts at certain moments.
1100 Under Windows (not Cygwin), the scripts should have the extension .bat.
1104 @item @value{sysconfdir}/tinc/@var{netname}/tinc-up
1105 This is the most important script.
1106 If it is present it will be executed right after the tinc daemon has been
1107 started and has connected to the virtual network device.
1108 It should be used to set up the corresponding network interface,
1109 but can also be used to start other things.
1110 Under Windows you can use the Network Connections control panel instead of creating this script.
1113 @item @value{sysconfdir}/tinc/@var{netname}/tinc-down
1114 This script is started right before the tinc daemon quits.
1116 @item @value{sysconfdir}/tinc/@var{netname}/hosts/@var{host}-up
1117 This script is started when the tinc daemon with name @var{host} becomes reachable.
1119 @item @value{sysconfdir}/tinc/@var{netname}/hosts/@var{host}-down
1120 This script is started when the tinc daemon with name @var{host} becomes unreachable.
1122 @item @value{sysconfdir}/tinc/@var{netname}/host-up
1123 This script is started when any host becomes reachable.
1125 @item @value{sysconfdir}/tinc/@var{netname}/host-down
1126 This script is started when any host becomes unreachable.
1128 @item @value{sysconfdir}/tinc/@var{netname}/subnet-up
1129 This script is started when a Subnet becomes reachable.
1130 The Subnet and the node it belongs to are passed in environment variables.
1132 @item @value{sysconfdir}/tinc/@var{netname}/subnet-down
1133 This script is started when a Subnet becomes unreachable.
1136 @cindex environment variables
1137 The scripts are started without command line arguments,
1138 but can make use of certain environment variables.
1139 Under UNIX like operating systems the names of environment variables must be preceded by a $ in scripts.
1140 Under Windows, in @file{.bat} files, they have to be put between % signs.
1145 If a netname was specified, this environment variable contains it.
1149 Contains the name of this tinc daemon.
1153 Contains the name of the virtual network device that tinc uses.
1157 Contains the name of the virtual network interface that tinc uses.
1158 This should be used for commands like ifconfig.
1162 When a host becomes (un)reachable, this is set to its name.
1163 If a subnet becomes (un)reachable, this is set to the owner of that subnet.
1165 @cindex REMOTEADDRESS
1167 When a host becomes (un)reachable, this is set to its real address.
1171 When a host becomes (un)reachable,
1172 this is set to the port number it uses for communication with other tinc daemons.
1176 When a subnet becomes (un)reachable, this is set to the subnet.
1181 @c ==================================================================
1182 @node How to configure
1183 @subsection How to configure
1185 @subsubheading Step 1. Creating the main configuration file
1187 The main configuration file will be called @file{@value{sysconfdir}/tinc/@var{netname}/tinc.conf}.
1188 Adapt the following example to create a basic configuration file:
1191 Name = @var{yourname}
1192 Device = @file{/dev/tap0}
1195 Then, if you know to which other tinc daemon(s) yours is going to connect,
1196 add `ConnectTo' values.
1198 @subsubheading Step 2. Creating your host configuration file
1200 If you added a line containing `Name = yourname' in the main configuarion file,
1201 you will need to create a host configuration file @file{@value{sysconfdir}/tinc/@var{netname}/hosts/yourname}.
1202 Adapt the following example to create a host configuration file:
1205 Address = your.real.hostname.org
1206 Subnet = 192.168.1.0/24
1209 You can also use an IP address instead of a hostname.
1210 The `Subnet' specifies the address range that is local for @emph{your part of the VPN only}.
1211 If you have multiple address ranges you can specify more than one `Subnet'.
1212 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).
1215 @c ==================================================================
1216 @node Generating keypairs
1217 @section Generating keypairs
1219 @cindex key generation
1220 Now that you have already created the main configuration file and your host configuration file,
1221 you can easily create a public/private keypair by entering the following command:
1224 tincctl -n @var{netname} generate-keys
1227 Tinc will generate a public and a private key and ask you where to put them.
1228 Just press enter to accept the defaults.
1231 @c ==================================================================
1232 @node Network interfaces
1233 @section Network interfaces
1235 Before tinc can start transmitting data over the tunnel, it must
1236 set up the virtual network interface.
1238 First, decide which IP addresses you want to have associated with these
1239 devices, and what network mask they must have.
1241 Tinc will open a virtual network device (@file{/dev/tun}, @file{/dev/tap0} or similar),
1242 which will also create a network interface called something like @samp{tun0}, @samp{tap0}.
1243 If you are using the Linux tun/tap driver, the network interface will by default have the same name as the @var{netname}.
1244 Under Windows you can change the name of the network interface from the Network Connections control panel.
1247 You can configure the network interface by putting ordinary ifconfig, route, and other commands
1248 to a script named @file{@value{sysconfdir}/tinc/@var{netname}/tinc-up}.
1249 When tinc starts, this script will be executed. When tinc exits, it will execute the script named
1250 @file{@value{sysconfdir}/tinc/@var{netname}/tinc-down}, but normally you don't need to create that script.
1252 An example @file{tinc-up} script:
1256 ifconfig $INTERFACE 192.168.1.1 netmask 255.255.0.0
1259 This script gives the interface an IP address and a netmask.
1260 The kernel will also automatically add a route to this interface, so normally you don't need
1261 to add route commands to the @file{tinc-up} script.
1262 The kernel will also bring the interface up after this command.
1264 The netmask is the mask of the @emph{entire} VPN network, not just your
1267 The exact syntax of the ifconfig and route commands differs from platform to platform.
1268 You can look up the commands for setting addresses and adding routes in @ref{Platform specific information},
1269 but it is best to consult the manpages of those utilities on your platform.
1272 @c ==================================================================
1273 @node Example configuration
1274 @section Example configuration
1278 Imagine the following situation. Branch A of our example `company' wants to connect
1279 three branch offices in B, C and D using the Internet. All four offices
1280 have a 24/7 connection to the Internet.
1282 A is going to serve as the center of the network. B and C will connect
1283 to A, and D will connect to C. Each office will be assigned their own IP
1287 A: net 10.1.0.0 mask 255.255.0.0 gateway 10.1.54.1 internet IP 1.2.3.4
1288 B: net 10.2.0.0 mask 255.255.0.0 gateway 10.2.1.12 internet IP 2.3.4.5
1289 C: net 10.3.0.0 mask 255.255.0.0 gateway 10.3.69.254 internet IP 3.4.5.6
1290 D: net 10.4.0.0 mask 255.255.0.0 gateway 10.4.3.32 internet IP 4.5.6.7
1293 Here, ``gateway'' is the VPN IP address of the machine that is running the
1294 tincd, and ``internet IP'' is the IP address of the firewall, which does not
1295 need to run tincd, but it must do a port forwarding of TCP and UDP on port
1296 655 (unless otherwise configured).
1298 In this example, it is assumed that eth0 is the interface that points to
1299 the inner (physical) LAN of the office, although this could also be the
1300 same as the interface that leads to the Internet. The configuration of
1301 the real interface is also shown as a comment, to give you an idea of
1302 how these example host is set up. All branches use the netname `company'
1303 for this particular VPN.
1305 @subsubheading For Branch A
1307 @emph{BranchA} would be configured like this:
1309 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1312 # Real interface of internal network:
1313 # ifconfig eth0 10.1.54.1 netmask 255.255.0.0
1315 ifconfig $INTERFACE 10.1.54.1 netmask 255.0.0.0
1318 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1325 On all hosts, @file{@value{sysconfdir}/tinc/company/hosts/BranchA} contains:
1328 Subnet = 10.1.0.0/16
1331 -----BEGIN RSA PUBLIC KEY-----
1333 -----END RSA PUBLIC KEY-----
1336 Note that the IP addresses of eth0 and tap0 are the same.
1337 This is quite possible, if you make sure that the netmasks of the interfaces are different.
1338 It is in fact recommended to give give both real internal network interfaces and tap interfaces the same IP address,
1339 since that will make things a lot easier to remember and set up.
1342 @subsubheading For Branch B
1344 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1347 # Real interface of internal network:
1348 # ifconfig eth0 10.2.43.8 netmask 255.255.0.0
1350 ifconfig $INTERFACE 10.2.1.12 netmask 255.0.0.0
1353 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1360 Note here that the internal address (on eth0) doesn't have to be the
1361 same as on the tap0 device. Also, ConnectTo is given so that no-one can
1362 connect to this node.
1364 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchB}:
1367 Subnet = 10.2.0.0/16
1370 -----BEGIN RSA PUBLIC KEY-----
1372 -----END RSA PUBLIC KEY-----
1376 @subsubheading For Branch C
1378 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1381 # Real interface of internal network:
1382 # ifconfig eth0 10.3.69.254 netmask 255.255.0.0
1384 ifconfig $INTERFACE 10.3.69.254 netmask 255.0.0.0
1387 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1395 C already has another daemon that runs on port 655, so they have to
1396 reserve another port for tinc. It knows the portnumber it has to listen on
1397 from it's own host configuration file.
1399 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchC}:
1403 Subnet = 10.3.0.0/16
1406 -----BEGIN RSA PUBLIC KEY-----
1408 -----END RSA PUBLIC KEY-----
1412 @subsubheading For Branch D
1414 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1417 # Real interface of internal network:
1418 # ifconfig eth0 10.4.3.32 netmask 255.255.0.0
1420 ifconfig $INTERFACE 10.4.3.32 netmask 255.0.0.0
1423 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1428 Device = /dev/net/tun
1431 D will be connecting to C, which has a tincd running for this network on
1432 port 2000. It knows the port number from the host configuration file.
1433 Also note that since D uses the tun/tap driver, the network interface
1434 will not be called `tun' or `tap0' or something like that, but will
1435 have the same name as netname.
1437 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchD}:
1440 Subnet = 10.4.0.0/16
1443 -----BEGIN RSA PUBLIC KEY-----
1445 -----END RSA PUBLIC KEY-----
1448 @subsubheading Key files
1450 A, B, C and D all have generated a public/private keypair with the following command:
1453 tincctl -n company generate-keys
1456 The private key is stored in @file{@value{sysconfdir}/tinc/company/rsa_key.priv},
1457 the public key is put into the host configuration file in the @file{@value{sysconfdir}/tinc/company/hosts/} directory.
1458 During key generation, tinc automatically guesses the right filenames based on the -n option and
1459 the Name directive in the @file{tinc.conf} file (if it is available).
1461 @subsubheading Starting
1463 After each branch has finished configuration and they have distributed
1464 the host configuration files amongst them, they can start their tinc daemons.
1465 They don't necessarily have to wait for the other branches to have started
1466 their daemons, tinc will try connecting until they are available.
1469 @c ==================================================================
1471 @chapter Running tinc
1473 If everything else is done, you can start tinc by typing the following command:
1476 tincd -n @var{netname}
1480 Tinc will detach from the terminal and continue to run in the background like a good daemon.
1481 If there are any problems however you can try to increase the debug level
1482 and look in the syslog to find out what the problems are.
1488 * Solving problems::
1490 * Sending bug reports::
1494 @c ==================================================================
1495 @node Runtime options
1496 @section Runtime options
1498 Besides the settings in the configuration file, tinc also accepts some
1499 command line options.
1501 @cindex command line
1502 @cindex runtime options
1506 @item -c, --config=@var{path}
1507 Read configuration options from the directory @var{path}. The default is
1508 @file{@value{sysconfdir}/tinc/@var{netname}/}.
1510 @item -D, --no-detach
1511 Don't fork and detach.
1512 This will also disable the automatic restart mechanism for fatal errors.
1515 @item -d, --debug=@var{level}
1516 Set debug level to @var{level}. The higher the debug level, the more gets
1517 logged. Everything goes via syslog.
1519 @item -n, --net=@var{netname}
1520 Use configuration for net @var{netname}. @xref{Multiple networks}.
1522 @item --controlsocket=@var{filename}
1523 Open control socket at @var{filename}. If unspecified, the default is
1524 @file{@value{localstatedir}/run/tinc.@var{netname}.control}.
1527 Lock tinc into main memory.
1528 This will prevent sensitive data like shared private keys to be written to the system swap files/partitions.
1530 @item --logfile[=@var{file}]
1531 Write log entries to a file instead of to the system logging facility.
1532 If @var{file} is omitted, the default is @file{@value{localstatedir}/log/tinc.@var{netname}.log}.
1534 @item --bypass-security
1535 Disables encryption and authentication.
1536 Only useful for debugging.
1539 Display a short reminder of these runtime options and terminate.
1542 Output version information and exit.
1546 @c ==================================================================
1551 You can also send the following signals to a running tincd process:
1557 Forces tinc to try to connect to all uplinks immediately.
1558 Usually tinc attempts to do this itself,
1559 but increases the time it waits between the attempts each time it failed,
1560 and if tinc didn't succeed to connect to an uplink the first time after it started,
1561 it defaults to the maximum time of 15 minutes.
1564 Partially rereads configuration files.
1565 Connections to hosts whose host config file are removed are closed.
1566 New outgoing connections specified in @file{tinc.conf} will be made.
1570 @c ==================================================================
1572 @section Debug levels
1574 @cindex debug levels
1575 The tinc daemon can send a lot of messages to the syslog.
1576 The higher the debug level, the more messages it will log.
1577 Each level inherits all messages of the previous level:
1583 This will log a message indicating tinc has started along with a version number.
1584 It will also log any serious error.
1587 This will log all connections that are made with other tinc daemons.
1590 This will log status and error messages from scripts and other tinc daemons.
1593 This will log all requests that are exchanged with other tinc daemons. These include
1594 authentication, key exchange and connection list updates.
1597 This will log a copy of everything received on the meta socket.
1600 This will log all network traffic over the virtual private network.
1604 @c ==================================================================
1605 @node Solving problems
1606 @section Solving problems
1608 If tinc starts without problems, but if the VPN doesn't work, you will have to find the cause of the problem.
1609 The first thing to do is to start tinc with a high debug level in the foreground,
1610 so you can directly see everything tinc logs:
1613 tincd -n @var{netname} -d5 -D
1616 If tinc does not log any error messages, then you might want to check the following things:
1619 @item @file{tinc-up} script
1620 Does this script contain the right commands?
1621 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.
1624 Does the Subnet (or Subnets) in the host configuration file of this host match the portion of the VPN that belongs to this host?
1626 @item Firewalls and NATs
1627 Do you have a firewall or a NAT device (a masquerading firewall or perhaps an ADSL router that performs masquerading)?
1628 If so, check that it allows TCP and UDP traffic on port 655.
1629 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.
1630 You can add @samp{TCPOnly = yes} to your host config file to force tinc to only use a single TCP connection,
1631 this works through most firewalls and NATs.
1636 @c ==================================================================
1637 @node Error messages
1638 @section Error messages
1640 What follows is a list of the most common error messages you might find in the logs.
1641 Some of them will only be visible if the debug level is high enough.
1644 @item Could not open /dev/tap0: No such device
1647 @item You forgot to `modprobe netlink_dev' or `modprobe ethertap'.
1648 @item You forgot to compile `Netlink device emulation' in the kernel.
1651 @item Can't write to /dev/net/tun: No such device
1654 @item You forgot to `modprobe tun'.
1655 @item You forgot to compile `Universal TUN/TAP driver' in the kernel.
1656 @item The tun device is located somewhere else in @file{/dev/}.
1659 @item Network address and prefix length do not match!
1662 @item The Subnet field must contain a @emph{network} address, trailing bits should be 0.
1663 @item If you only want to use one IP address, set the netmask to /32.
1666 @item Error reading RSA key file `rsa_key.priv': No such file or directory
1669 @item You forgot to create a public/private keypair.
1670 @item Specify the complete pathname to the private key file with the @samp{PrivateKeyFile} option.
1673 @item Warning: insecure file permissions for RSA private key file `rsa_key.priv'!
1676 @item The private key file is readable by users other than root.
1677 Use chmod to correct the file permissions.
1680 @item Creating metasocket failed: Address family not supported
1683 @item By default tinc tries to create both IPv4 and IPv6 sockets.
1684 On some platforms this might not be implemented.
1685 If the logs show @samp{Ready} later on, then at least one metasocket was created,
1686 and you can ignore this message.
1687 You can add @samp{AddressFamily = ipv4} to @file{tinc.conf} to prevent this from happening.
1690 @item Cannot route packet: unknown IPv4 destination 1.2.3.4
1693 @item You try to send traffic to a host on the VPN for which no Subnet is known.
1694 @item If it is a broadcast address (ending in .255), it probably is a samba server or a Windows host sending broadcast packets.
1698 @item Cannot route packet: ARP request for unknown address 1.2.3.4
1701 @item You try to send traffic to a host on the VPN for which no Subnet is known.
1704 @item Packet with destination 1.2.3.4 is looping back to us!
1707 @item Something is not configured right. Packets are being sent out to the
1708 virtual network device, but according to the Subnet directives in your host configuration
1709 file, those packets should go to your own host. Most common mistake is that
1710 you have a Subnet line in your host configuration file with a prefix length which is
1711 just as large as the prefix of the virtual network interface. The latter should in almost all
1712 cases be larger. Rethink your configuration.
1713 Note that you will only see this message if you specified a debug
1714 level of 5 or higher!
1715 @item Chances are that a @samp{Subnet = ...} line in the host configuration file of this tinc daemon is wrong.
1716 Change it to a subnet that is accepted locally by another interface,
1717 or if that is not the case, try changing the prefix length into /32.
1720 @item Node foo (1.2.3.4) is not reachable
1723 @item Node foo does not have a connection anymore, its tinc daemon is not running or its connection to the Internet is broken.
1726 @item Received UDP packet from unknown source 1.2.3.4 (port 12345)
1729 @item If you see this only sporadically, it is harmless and caused by a node sending packets using an old key.
1730 @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.
1731 You can add @samp{TCPOnly = yes} to host configuration files to force all VPN traffic to go over a TCP connection.
1734 @item Got bad/bogus/unauthorized REQUEST from foo (1.2.3.4 port 12345)
1737 @item Node foo does not have the right public/private keypair.
1738 Generate new keypairs and distribute them again.
1739 @item An attacker tries to gain access to your VPN.
1740 @item A network error caused corruption of metadata sent from foo.
1745 @c ==================================================================
1746 @node Sending bug reports
1747 @section Sending bug reports
1749 If you really can't find the cause of a problem, or if you suspect tinc is not working right,
1750 you can send us a bugreport, see @ref{Contact information}.
1751 Be sure to include the following information in your bugreport:
1754 @item A clear description of what you are trying to achieve and what the problem is.
1755 @item What platform (operating system, version, hardware architecture) and which version of tinc you use.
1756 @item If compiling tinc fails, a copy of @file{config.log} and the error messages you get.
1757 @item Otherwise, a copy of @file{tinc.conf}, @file{tinc-up} and all files in the @file{hosts/} directory.
1758 @item The output of the commands @samp{ifconfig -a} and @samp{route -n} (or @samp{netstat -rn} if that doesn't work).
1759 @item The output of any command that fails to work as it should (like ping or traceroute).
1762 @c ==================================================================
1763 @node Controlling tinc
1764 @chapter Controlling tinc
1766 You can control and inspect a running @samp{tincd} through the @samp{tincctl}
1767 command. A quick example:
1770 tincctl -n @var{netname} reload
1774 * tincctl runtime options::
1775 * tincctl commands::
1779 @c ==================================================================
1780 @node tincctl runtime options
1781 @section tincctl runtime options
1785 @item -c, --config=@var{path}
1786 Read configuration options from the directory @var{path}. The default is
1787 @file{@value{sysconfdir}/tinc/@var{netname}/}.
1789 @item -n, --net=@var{netname}
1790 Use configuration for net @var{netname}. @xref{Multiple networks}.
1792 @item --controlsocket=@var{filename}
1793 Open control socket at @var{filename}. If unspecified, the default is
1794 @file{@value{localstatedir}/run/tinc.@var{netname}.control}.
1797 Display a short reminder of runtime options and commands, then terminate.
1800 Output version information and exit.
1805 @c ==================================================================
1806 @node tincctl commands
1807 @section tincctl commands
1819 Restart @samp{tincd}.
1822 Partially rereads configuration files. Connections to hosts whose host
1823 config files are removed are closed. New outgoing connections specified
1824 in @file{tinc.conf} will be made.
1827 Shows the PID of the currently running @samp{tincd}.
1829 @item generate-keys [@var{bits}]
1830 Generate public/private keypair of @var{bits} length. If @var{bits} is not specified,
1831 1024 is the default. tinc will ask where you want to store the files,
1832 but will default to the configuration directory (you can use the -c or -n
1836 Dump a list of all known nodes in the VPN.
1839 Dump a list of all known connections in the VPN.
1842 Dump a list of all known subnets in the VPN.
1844 @item dump connections
1845 Dump a list of all meta connections with ourself.
1848 Dump a graph of the VPN in dotty format.
1851 Purges all information remembered about unreachable nodes.
1853 @item debug @var{level}
1854 Sets debug level to @var{level}.
1859 @c ==================================================================
1860 @node Technical information
1861 @chapter Technical information
1866 * The meta-protocol::
1871 @c ==================================================================
1872 @node The connection
1873 @section The connection
1876 Tinc is a daemon that takes VPN data and transmit that to another host
1877 computer over the existing Internet infrastructure.
1881 * The meta-connection::
1885 @c ==================================================================
1886 @node The UDP tunnel
1887 @subsection The UDP tunnel
1889 @cindex virtual network device
1891 The data itself is read from a character device file, the so-called
1892 @emph{virtual network device}. This device is associated with a network
1893 interface. Any data sent to this interface can be read from the device,
1894 and any data written to the device gets sent from the interface.
1895 There are two possible types of virtual network devices:
1896 `tun' style, which are point-to-point devices which can only handle IPv4 and/or IPv6 packets,
1897 and `tap' style, which are Ethernet devices and handle complete Ethernet frames.
1899 So when tinc reads an Ethernet frame from the device, it determines its
1900 type. When tinc is in it's default routing mode, it can handle IPv4 and IPv6
1901 packets. Depending on the Subnet lines, it will send the packets off to their destination IP address.
1902 In the `switch' and `hub' mode, tinc will use broadcasts and MAC address discovery
1903 to deduce the destination of the packets.
1904 Since the latter modes only depend on the link layer information,
1905 any protocol that runs over Ethernet is supported (for instance IPX and Appletalk).
1906 However, only `tap' style devices provide this information.
1908 After the destination has been determined,
1909 the packet will be compressed (optionally),
1910 a sequence number will be added to the packet,
1911 the packet will then be encrypted
1912 and a message authentication code will be appended.
1914 @cindex encapsulating
1916 When that is done, time has come to actually transport the
1917 packet to the destination computer. We do this by sending the packet
1918 over an UDP connection to the destination host. This is called
1919 @emph{encapsulating}, the VPN packet (though now encrypted) is
1920 encapsulated in another IP datagram.
1922 When the destination receives this packet, the same thing happens, only
1923 in reverse. So it checks the message authentication code, decrypts the contents of the UDP datagram,
1924 checks the sequence number
1925 and writes the decrypted information to its own virtual network device.
1927 If the virtual network device is a `tun' device (a point-to-point tunnel),
1928 there is no problem for the kernel to accept a packet.
1929 However, if it is a `tap' device (this is the only available type on FreeBSD),
1930 the destination MAC address must match that of the virtual network interface.
1931 If tinc is in it's default routing mode, ARP does not work, so the correct destination MAC
1932 can not be known by the sending host.
1933 Tinc solves this by letting the receiving end detect the MAC address of its own virtual network interface
1934 and overwriting the destination MAC address of the received packet.
1936 In switch or hub modes ARP does work so the sender already knows the correct destination MAC address.
1937 In those modes every interface should have a unique MAC address, so make sure they are not the same.
1938 Because switch and hub modes rely on MAC addresses to function correctly,
1939 these modes cannot be used on the following operating systems which don't have a `tap' style virtual network device:
1940 OpenBSD, NetBSD, Darwin and Solaris.
1943 @c ==================================================================
1944 @node The meta-connection
1945 @subsection The meta-connection
1947 Having only a UDP connection available is not enough. Though suitable
1948 for transmitting data, we want to be able to reliably send other
1949 information, such as routing and session key information to somebody.
1952 TCP is a better alternative, because it already contains protection
1953 against information being lost, unlike UDP.
1955 So we establish two connections. One for the encrypted VPN data, and one
1956 for other information, the meta-data. Hence, we call the second
1957 connection the meta-connection. We can now be sure that the
1958 meta-information doesn't get lost on the way to another computer.
1960 @cindex data-protocol
1961 @cindex meta-protocol
1962 Like with any communication, we must have a protocol, so that everybody
1963 knows what everything stands for, and how she should react. Because we
1964 have two connections, we also have two protocols. The protocol used for
1965 the UDP data is the ``data-protocol,'' the other one is the
1968 The reason we don't use TCP for both protocols is that UDP is much
1969 better for encapsulation, even while it is less reliable. The real
1970 problem is that when TCP would be used to encapsulate a TCP stream
1971 that's on the private network, for every packet sent there would be
1972 three ACKs sent instead of just one. Furthermore, if there would be
1973 a timeout, both TCP streams would sense the timeout, and both would
1974 start re-sending packets.
1977 @c ==================================================================
1978 @node The meta-protocol
1979 @section The meta-protocol
1981 The meta protocol is used to tie all tinc daemons together, and
1982 exchange information about which tinc daemon serves which virtual
1985 The meta protocol consists of requests that can be sent to the other
1986 side. Each request has a unique number and several parameters. All
1987 requests are represented in the standard ASCII character set. It is
1988 possible to use tools such as telnet or netcat to connect to a tinc
1989 daemon started with the --bypass-security option
1990 and to read and write requests by hand, provided that one
1991 understands the numeric codes sent.
1993 The authentication scheme is described in @ref{Authentication protocol}. After a
1994 successful authentication, the server and the client will exchange all the
1995 information about other tinc daemons and subnets they know of, so that both
1996 sides (and all the other tinc daemons behind them) have their information
2003 ------------------------------------------------------------------
2004 ADD_EDGE node1 node2 21.32.43.54 655 222 0
2005 | | | | | +-> options
2006 | | | | +----> weight
2007 | | | +--------> UDP port of node2
2008 | | +----------------> real address of node2
2009 | +-------------------------> name of destination node
2010 +-------------------------------> name of source node
2012 ADD_SUBNET node 192.168.1.0/24
2013 | | +--> prefixlength
2014 | +--------> network address
2015 +------------------> owner of this subnet
2016 ------------------------------------------------------------------
2019 The ADD_EDGE messages are to inform other tinc daemons that a connection between
2020 two nodes exist. The address of the destination node is available so that
2021 VPN packets can be sent directly to that node.
2023 The ADD_SUBNET messages inform other tinc daemons that certain subnets belong
2024 to certain nodes. tinc will use it to determine to which node a VPN packet has
2031 ------------------------------------------------------------------
2032 DEL_EDGE node1 node2
2033 | +----> name of destination node
2034 +----------> name of source node
2036 DEL_SUBNET node 192.168.1.0/24
2037 | | +--> prefixlength
2038 | +--------> network address
2039 +------------------> owner of this subnet
2040 ------------------------------------------------------------------
2043 In case a connection between two daemons is closed or broken, DEL_EDGE messages
2044 are sent to inform the other daemons of that fact. Each daemon will calculate a
2045 new route to the the daemons, or mark them unreachable if there isn't any.
2052 ------------------------------------------------------------------
2053 REQ_KEY origin destination
2054 | +--> name of the tinc daemon it wants the key from
2055 +----------> name of the daemon that wants the key
2057 ANS_KEY origin destination 4ae0b0a82d6e0078 91 64 4
2058 | | \______________/ | | +--> MAC length
2059 | | | | +-----> digest algorithm
2060 | | | +--------> cipher algorithm
2061 | | +--> 128 bits key
2062 | +--> name of the daemon that wants the key
2063 +----------> name of the daemon that uses this key
2066 +--> daemon that has changed it's packet key
2067 ------------------------------------------------------------------
2070 The keys used to encrypt VPN packets are not sent out directly. This is
2071 because it would generate a lot of traffic on VPNs with many daemons, and
2072 chances are that not every tinc daemon will ever send a packet to every
2073 other daemon. Instead, if a daemon needs a key it sends a request for it
2074 via the meta connection of the nearest hop in the direction of the
2081 ------------------------------------------------------------------
2084 ------------------------------------------------------------------
2087 There is also a mechanism to check if hosts are still alive. Since network
2088 failures or a crash can cause a daemon to be killed without properly
2089 shutting down the TCP connection, this is necessary to keep an up to date
2090 connection list. PINGs are sent at regular intervals, except when there
2091 is also some other traffic. A little bit of salt (random data) is added
2092 with each PING and PONG message, to make sure that long sequences of PING/PONG
2093 messages without any other traffic won't result in known plaintext.
2095 This basically covers what is sent over the meta connection by tinc.
2098 @c ==================================================================
2104 Tinc got its name from ``TINC,'' short for @emph{There Is No Cabal}; the
2105 alleged Cabal was/is an organisation that was said to keep an eye on the
2106 entire Internet. As this is exactly what you @emph{don't} want, we named
2107 the tinc project after TINC.
2110 But in order to be ``immune'' to eavesdropping, you'll have to encrypt
2111 your data. Because tinc is a @emph{Secure} VPN (SVPN) daemon, it does
2112 exactly that: encrypt.
2113 Tinc by default uses blowfish encryption with 128 bit keys in CBC mode, 32 bit
2114 sequence numbers and 4 byte long message authentication codes to make sure
2115 eavesdroppers cannot get and cannot change any information at all from the
2116 packets they can intercept. The encryption algorithm and message authentication
2117 algorithm can be changed in the configuration. The length of the message
2118 authentication codes is also adjustable. The length of the key for the
2119 encryption algorithm is always the default length used by OpenSSL.
2122 * Authentication protocol::
2123 * Encryption of network packets::
2128 @c ==================================================================
2129 @node Authentication protocol
2130 @subsection Authentication protocol
2132 @cindex authentication
2133 A new scheme for authentication in tinc has been devised, which offers some
2134 improvements over the protocol used in 1.0pre2 and 1.0pre3. Explanation is
2144 --------------------------------------------------------------------------
2145 client <attempts connection>
2147 server <accepts connection>
2151 +-------> name of tinc daemon
2155 +-------> name of tinc daemon
2157 client META_KEY 5f0823a93e35b69e...7086ec7866ce582b
2158 \_________________________________/
2159 +-> RSAKEYLEN bits totally random string S1,
2160 encrypted with server's public RSA key
2162 server META_KEY 6ab9c1640388f8f0...45d1a07f8a672630
2163 \_________________________________/
2164 +-> RSAKEYLEN bits totally random string S2,
2165 encrypted with client's public RSA key
2168 - the client will symmetrically encrypt outgoing traffic using S1
2169 - the server will symmetrically encrypt outgoing traffic using S2
2171 client CHALLENGE da02add1817c1920989ba6ae2a49cecbda0
2172 \_________________________________/
2173 +-> CHALLEN bits totally random string H1
2175 server CHALLENGE 57fb4b2ccd70d6bb35a64c142f47e61d57f
2176 \_________________________________/
2177 +-> CHALLEN bits totally random string H2
2179 client CHAL_REPLY 816a86
2180 +-> 160 bits SHA1 of H2
2182 server CHAL_REPLY 928ffe
2183 +-> 160 bits SHA1 of H1
2185 After the correct challenge replies are received, both ends have proved
2186 their identity. Further information is exchanged.
2188 client ACK 655 123 0
2190 | +----> estimated weight
2191 +--------> listening port of client
2193 server ACK 655 321 0
2195 | +----> estimated weight
2196 +--------> listening port of server
2197 --------------------------------------------------------------------------
2200 This new scheme has several improvements, both in efficiency and security.
2202 First of all, the server sends exactly the same kind of messages over the wire
2203 as the client. The previous versions of tinc first authenticated the client,
2204 and then the server. This scheme even allows both sides to send their messages
2205 simultaneously, there is no need to wait for the other to send something first.
2206 This means that any calculations that need to be done upon sending or receiving
2207 a message can also be done in parallel. This is especially important when doing
2208 RSA encryption/decryption. Given that these calculations are the main part of
2209 the CPU time spent for the authentication, speed is improved by a factor 2.
2211 Second, only one RSA encrypted message is sent instead of two. This reduces the
2212 amount of information attackers can see (and thus use for a cryptographic
2213 attack). It also improves speed by a factor two, making the total speedup a
2216 Third, and most important:
2217 The symmetric cipher keys are exchanged first, the challenge is done
2218 afterwards. In the previous authentication scheme, because a man-in-the-middle
2219 could pass the challenge/chal_reply phase (by just copying the messages between
2220 the two real tinc daemons), but no information was exchanged that was really
2221 needed to read the rest of the messages, the challenge/chal_reply phase was of
2222 no real use. The man-in-the-middle was only stopped by the fact that only after
2223 the ACK messages were encrypted with the symmetric cipher. Potentially, it
2224 could even send it's own symmetric key to the server (if it knew the server's
2225 public key) and read some of the metadata the server would send it (it was
2226 impossible for the mitm to read actual network packets though). The new scheme
2227 however prevents this.
2229 This new scheme makes sure that first of all, symmetric keys are exchanged. The
2230 rest of the messages are then encrypted with the symmetric cipher. Then, each
2231 side can only read received messages if they have their private key. The
2232 challenge is there to let the other side know that the private key is really
2233 known, because a challenge reply can only be sent back if the challenge is
2234 decrypted correctly, and that can only be done with knowledge of the private
2237 Fourth: the first thing that is sent via the symmetric cipher encrypted
2238 connection is a totally random string, so that there is no known plaintext (for
2239 an attacker) in the beginning of the encrypted stream.
2242 @c ==================================================================
2243 @node Encryption of network packets
2244 @subsection Encryption of network packets
2247 A data packet can only be sent if the encryption key is known to both
2248 parties, and the connection is activated. If the encryption key is not
2249 known, a request is sent to the destination using the meta connection
2250 to retrieve it. The packet is stored in a queue while waiting for the
2254 The UDP packet containing the network packet from the VPN has the following layout:
2257 ... | IP header | UDP header | seqno | VPN packet | MAC | UDP trailer
2258 \___________________/\_____/
2260 V +---> digest algorithm
2261 Encrypted with symmetric cipher
2264 So, the entire VPN packet is encrypted using a symmetric cipher, including a 32 bits
2265 sequence number that is added in front of the actual VPN packet, to act as a unique
2266 IV for each packet and to prevent replay attacks. A message authentication code
2267 is added to the UDP packet to prevent alteration of packets. By default the
2268 first 4 bytes of the digest are used for this, but this can be changed using
2269 the MACLength configuration variable.
2271 @c ==================================================================
2272 @node Security issues
2273 @subsection Security issues
2275 In August 2000, we discovered the existence of a security hole in all versions
2276 of tinc up to and including 1.0pre2. This had to do with the way we exchanged
2277 keys. Since then, we have been working on a new authentication scheme to make
2278 tinc as secure as possible. The current version uses the OpenSSL library and
2279 uses strong authentication with RSA keys.
2281 On the 29th of December 2001, Jerome Etienne posted a security analysis of tinc
2282 1.0pre4. Due to a lack of sequence numbers and a message authentication code
2283 for each packet, an attacker could possibly disrupt certain network services or
2284 launch a denial of service attack by replaying intercepted packets. The current
2285 version adds sequence numbers and message authentication codes to prevent such
2288 On the 15th of September 2003, Peter Gutmann posted a security analysis of tinc
2289 1.0.1. He argues that the 32 bit sequence number used by tinc is not a good IV,
2290 that tinc's default length of 4 bytes for the MAC is too short, and he doesn't
2291 like tinc's use of RSA during authentication. We do not know of a security hole
2292 in this version of tinc, but tinc's security is not as strong as TLS or IPsec.
2293 We will address these issues in tinc 2.0.
2295 Cryptography is a hard thing to get right. We cannot make any
2296 guarantees. Time, review and feedback are the only things that can
2297 prove the security of any cryptographic product. If you wish to review
2298 tinc or give us feedback, you are stronly encouraged to do so.
2301 @c ==================================================================
2302 @node Platform specific information
2303 @chapter Platform specific information
2306 * Interface configuration::
2310 @c ==================================================================
2311 @node Interface configuration
2312 @section Interface configuration
2314 When configuring an interface, one normally assigns it an address and a
2315 netmask. The address uniquely identifies the host on the network attached to
2316 the interface. The netmask, combined with the address, forms a subnet. It is
2317 used to add a route to the routing table instructing the kernel to send all
2318 packets which fall into that subnet to that interface. Because all packets for
2319 the entire VPN should go to the virtual network interface used by tinc, the
2320 netmask should be such that it encompasses the entire VPN.
2324 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2326 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2327 @item Linux iproute2
2328 @tab @code{ip addr add} @var{address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2330 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2332 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2334 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2336 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2337 @item Darwin (MacOS/X)
2338 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2340 @tab @code{netsh interface ip set address} @var{interface} @code{static} @var{address} @var{netmask}
2346 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2348 @tab @code{ifconfig} @var{interface} @code{add} @var{address}@code{/}@var{prefixlength}
2350 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2352 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2354 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2356 @tab @code{ifconfig} @var{interface} @code{inet6 plumb up}
2358 @tab @code{ifconfig} @var{interface} @code{inet6 addif} @var{address} @var{address}
2359 @item Darwin (MacOS/X)
2360 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2362 @tab @code{netsh interface ipv6 add address} @var{interface} @code{static} @var{address}/@var{prefixlength}
2366 @c ==================================================================
2370 In some cases it might be necessary to add more routes to the virtual network
2371 interface. There are two ways to indicate which interface a packet should go
2372 to, one is to use the name of the interface itself, another way is to specify
2373 the (local) address that is assigned to that interface (@var{local_address}). The
2374 former way is unambiguous and therefore preferable, but not all platforms
2377 Adding routes to IPv4 subnets:
2379 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2381 @tab @code{route add -net} @var{network_address} @code{netmask} @var{netmask} @var{interface}
2382 @item Linux iproute2
2383 @tab @code{ip route add} @var{network_address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2385 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2387 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2389 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2391 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address} @code{-interface}
2392 @item Darwin (MacOS/X)
2393 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2395 @tab @code{netsh routing ip add persistentroute} @var{network_address} @var{netmask} @var{interface} @var{local_address}
2398 Adding routes to IPv6 subnets:
2400 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2402 @tab @code{route add -A inet6} @var{network_address}@code{/}@var{prefixlength} @var{interface}
2403 @item Linux iproute2
2404 @tab @code{ip route add} @var{network_address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2406 @tab @code{route add -inet6} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2408 @tab @code{route add -inet6} @var{network_address} @var{local_address} @code{-prefixlen} @var{prefixlength}
2410 @tab @code{route add -inet6} @var{network_address} @var{local_address} @code{-prefixlen} @var{prefixlength}
2412 @tab @code{route add -inet6} @var{network_address}@code{/}@var{prefixlength} @var{local_address} @code{-interface}
2413 @item Darwin (MacOS/X)
2416 @tab @code{netsh interface ipv6 add route} @var{network address}/@var{prefixlength} @var{interface}
2420 @c ==================================================================
2426 * Contact information::
2431 @c ==================================================================
2432 @node Contact information
2433 @section Contact information
2436 Tinc's website is at @url{http://www.tinc-vpn.org/},
2437 this server is located in the Netherlands.
2440 We have an IRC channel on the FreeNode and OFTC IRC networks. Connect to
2441 @uref{http://www.freenode.net/, irc.freenode.net}
2443 @uref{http://www.oftc.net/, irc.oftc.net}
2444 and join channel #tinc.
2447 @c ==================================================================
2452 @item Ivo Timmermans (zarq) (@email{ivo@@tinc-vpn.org})
2453 @item Guus Sliepen (guus) (@email{guus@@tinc-vpn.org})
2456 We have received a lot of valuable input from users. With their help,
2457 tinc has become the flexible and robust tool that it is today. We have
2458 composed a list of contributions, in the file called @file{THANKS} in
2459 the source distribution.
2462 @c ==================================================================
2464 @unnumbered Concept Index
2466 @c ==================================================================
2470 @c ==================================================================