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{} 1998-2010 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{} 1998-2010 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.
345 @c ==================================================================
350 For all cryptography-related functions, tinc uses the functions provided
351 by the OpenSSL library.
353 If this library is not installed, you wil get an error when configuring
354 tinc for build. Support for running tinc without having OpenSSL
355 installed @emph{may} be added in the future.
357 You can use your operating system's package manager to install this if
358 available. Make sure you install the development AND runtime versions
361 If you have to install OpenSSL manually, you can get the source code
362 from @url{http://www.openssl.org/}. Instructions on how to configure,
363 build and install this package are included within the package. Please
364 make sure you build development and runtime libraries (which is the
367 If you installed the OpenSSL libraries from source, it may be necessary
368 to let configure know where they are, by passing configure one of the
369 --with-openssl-* parameters.
372 --with-openssl=DIR OpenSSL library and headers prefix
373 --with-openssl-include=DIR OpenSSL headers directory
374 (Default is OPENSSL_DIR/include)
375 --with-openssl-lib=DIR OpenSSL library directory
376 (Default is OPENSSL_DIR/lib)
380 @subsubheading License
383 The complete source code of tinc is covered by the GNU GPL version 2.
384 Since the license under which OpenSSL is distributed is not directly
385 compatible with the terms of the GNU GPL
386 @uref{http://www.openssl.org/support/faq.html#LEGAL2}, we
387 include an exemption to the GPL (see also the file COPYING.README) to allow
388 everyone to create a statically or dynamically linked executable:
391 This program is released under the GPL with the additional exemption
392 that compiling, linking, and/or using OpenSSL is allowed. You may
393 provide binary packages linked to the OpenSSL libraries, provided that
394 all other requirements of the GPL are met.
397 Since the LZO library used by tinc is also covered by the GPL,
398 we also present the following exemption:
401 Hereby I grant a special exception to the tinc VPN project
402 (http://www.tinc-vpn.org/) to link the LZO library with the OpenSSL library
403 (http://www.openssl.org).
405 Markus F.X.J. Oberhumer
409 @c ==================================================================
414 For the optional compression of UDP packets, tinc uses the functions provided
417 If this library is not installed, you wil get an error when configuring
418 tinc for build. Support for running tinc without having zlib
419 installed @emph{may} be added in the future.
421 You can use your operating system's package manager to install this if
422 available. Make sure you install the development AND runtime versions
425 If you have to install zlib manually, you can get the source code
426 from @url{http://www.gzip.org/zlib/}. Instructions on how to configure,
427 build and install this package are included within the package. Please
428 make sure you build development and runtime libraries (which is the
432 @c ==================================================================
437 Another form of compression is offered using the lzo library.
439 If this library is not installed, you wil get an error when configuring
440 tinc for build. Support for running tinc without having lzo
441 installed @emph{may} be added in the future.
443 You can use your operating system's package manager to install this if
444 available. Make sure you install the development AND runtime versions
447 If you have to install lzo manually, you can get the source code
448 from @url{http://www.oberhumer.com/opensource/lzo/}. Instructions on how to configure,
449 build and install this package are included within the package. Please
450 make sure you build development and runtime libraries (which is the
463 @c ==================================================================
465 @chapter Installation
467 If you use Debian, you may want to install one of the
468 precompiled packages for your system. These packages are equipped with
469 system startup scripts and sample configurations.
471 If you cannot use one of the precompiled packages, or you want to compile tinc
472 for yourself, you can use the source. The source is distributed under
473 the GNU General Public License (GPL). Download the source from the
474 @uref{http://www.tinc-vpn.org/download, download page}, which has
475 the checksums of these files listed; you may wish to check these with
476 md5sum before continuing.
478 Tinc comes in a convenient autoconf/automake package, which you can just
479 treat the same as any other package. Which is just untar it, type
480 `./configure' and then `make'.
481 More detailed instructions are in the file @file{INSTALL}, which is
482 included in the source distribution.
485 * Building and installing tinc::
490 @c ==================================================================
491 @node Building and installing tinc
492 @section Building and installing tinc
494 Detailed instructions on configuring the source, building tinc and installing tinc
495 can be found in the file called @file{INSTALL}.
497 @cindex binary package
498 If you happen to have a binary package for tinc for your distribution,
499 you can use the package management tools of that distribution to install tinc.
500 The documentation that comes along with your distribution will tell you how to do that.
503 * Darwin (MacOS/X) build environment::
504 * Cygwin (Windows) build environment::
505 * MinGW (Windows) build environment::
509 @c ==================================================================
510 @node Darwin (MacOS/X) build environment
511 @subsection Darwin (MacOS/X) build environment
513 In order to build tinc on Darwin, you need to install the MacOS/X Developer Tools
514 from @uref{http://developer.apple.com/tools/macosxtools.html} and
515 a recent version of Fink from @uref{http://fink.sourceforge.net/}.
517 After installation use fink to download and install the following packages:
518 autoconf25, automake, dlcompat, m4, openssl, zlib and lzo.
520 @c ==================================================================
521 @node Cygwin (Windows) build environment
522 @subsection Cygwin (Windows) build environment
524 If Cygwin hasn't already been installed, install it directly from
525 @uref{http://www.cygwin.com/}.
527 When tinc is compiled in a Cygwin environment, it can only be run in this environment,
528 but all programs, including those started outside the Cygwin environment, will be able to use the VPN.
529 It will also support all features.
531 @c ==================================================================
532 @node MinGW (Windows) build environment
533 @subsection MinGW (Windows) build environment
535 You will need to install the MinGW environment from @uref{http://www.mingw.org}.
537 When tinc is compiled using MinGW it runs natively under Windows,
538 it is not necessary to keep MinGW installed.
540 When detaching, tinc will install itself as a service,
541 which will be restarted automatically after reboots.
544 @c ==================================================================
546 @section System files
548 Before you can run tinc, you must make sure you have all the needed
549 files on your system.
557 @c ==================================================================
559 @subsection Device files
562 Most operating systems nowadays come with the necessary device files by default,
563 or they have a mechanism to create them on demand.
565 If you use Linux and do not have udev installed,
566 you may need to create the following device file if it does not exist:
569 mknod -m 600 /dev/net/tun c 10 200
573 @c ==================================================================
575 @subsection Other files
577 @subsubheading @file{/etc/networks}
579 You may add a line to @file{/etc/networks} so that your VPN will get a
580 symbolic name. For example:
586 @subsubheading @file{/etc/services}
589 You may add this line to @file{/etc/services}. The effect is that you
590 may supply a @samp{tinc} as a valid port number to some programs. The
591 number 655 is registered with the IANA.
596 # Ivo Timmermans <ivo@@tinc-vpn.org>
611 @c ==================================================================
613 @chapter Configuration
616 * Configuration introduction::
617 * Multiple networks::
618 * How connections work::
619 * Configuration files::
620 * Generating keypairs::
621 * Network interfaces::
622 * Example configuration::
625 @c ==================================================================
626 @node Configuration introduction
627 @section Configuration introduction
629 Before actually starting to configure tinc and editing files,
630 make sure you have read this entire section so you know what to expect.
631 Then, make it clear to yourself how you want to organize your VPN:
632 What are the nodes (computers running tinc)?
633 What IP addresses/subnets do they have?
634 What is the network mask of the entire VPN?
635 Do you need special firewall rules?
636 Do you have to set up masquerading or forwarding rules?
637 Do you want to run tinc in router mode or switch mode?
638 These questions can only be answered by yourself,
639 you will not find the answers in this documentation.
640 Make sure you have an adequate understanding of networks in general.
641 @cindex Network Administrators Guide
642 A good resource on networking is the
643 @uref{http://www.linuxdoc.org/LDP/nag2/, Linux Network Administrators Guide}.
645 If you have everything clearly pictured in your mind,
646 proceed in the following order:
647 First, generate the configuration files (@file{tinc.conf}, your host configuration file, @file{tinc-up} and perhaps @file{tinc-down}).
648 Then generate the keypairs.
649 Finally, distribute the host configuration files.
650 These steps are described in the subsections below.
653 @c ==================================================================
654 @node Multiple networks
655 @section Multiple networks
657 @cindex multiple networks
659 In order to allow you to run more than one tinc daemon on one computer,
660 for instance if your computer is part of more than one VPN,
661 you can assign a @var{netname} to your VPN.
662 It is not required if you only run one tinc daemon,
663 it doesn't even have to be the same on all the sites of your VPN,
664 but it is recommended that you choose one anyway.
666 We will asume you use a netname throughout this document.
667 This means that you call tincd with the -n argument,
668 which will assign a netname to this daemon.
670 The effect of this is that the daemon will set its configuration
671 root to @file{@value{sysconfdir}/tinc/@var{netname}/}, where @var{netname} is your argument to the -n
672 option. You'll notice that it appears in syslog as @file{tinc.@var{netname}}.
674 However, it is not strictly necessary that you call tinc with the -n
675 option. In this case, the network name would just be empty, and it will
676 be used as such. tinc now looks for files in @file{@value{sysconfdir}/tinc/}, instead of
677 @file{@value{sysconfdir}/tinc/@var{netname}/}; the configuration file should be @file{@value{sysconfdir}/tinc/tinc.conf},
678 and the host configuration files are now expected to be in @file{@value{sysconfdir}/tinc/hosts/}.
680 But it is highly recommended that you use this feature of tinc, because
681 it will be so much clearer whom your daemon talks to. Hence, we will
682 assume that you use it.
685 @c ==================================================================
686 @node How connections work
687 @section How connections work
689 When tinc starts up, it parses the command-line options and then
690 reads in the configuration file tinc.conf.
691 If it sees one or more `ConnectTo' values pointing to other tinc daemons in that file,
692 it will try to connect to those other daemons.
693 Whether this succeeds or not and whether `ConnectTo' is specified or not,
694 tinc will listen for incoming connection from other deamons.
695 If you did specify a `ConnectTo' value and the other side is not responding,
696 tinc will keep retrying.
697 This means that once started, tinc will stay running until you tell it to stop,
698 and failures to connect to other tinc daemons will not stop your tinc daemon
699 for trying again later.
700 This means you don't have to intervene if there are temporary network problems.
704 There is no real distinction between a server and a client in tinc.
705 If you wish, you can view a tinc daemon without a `ConnectTo' value as a server,
706 and one which does specify such a value as a client.
707 It does not matter if two tinc daemons have a `ConnectTo' value pointing to each other however.
710 @c ==================================================================
711 @node Configuration files
712 @section Configuration files
714 The actual configuration of the daemon is done in the file
715 @file{@value{sysconfdir}/tinc/@var{netname}/tinc.conf} and at least one other file in the directory
716 @file{@value{sysconfdir}/tinc/@var{netname}/hosts/}.
718 These file consists of comments (lines started with a #) or assignments
725 The variable names are case insensitive, and any spaces, tabs, newlines
726 and carriage returns are ignored. Note: it is not required that you put
727 in the `=' sign, but doing so improves readability. If you leave it
728 out, remember to replace it with at least one space character.
730 The server configuration is complemented with host specific configuration (see
731 the next section). Although all host configuration options for the local node
732 listed in this document can also be put in
733 @file{@value{sysconfdir}/tinc/@var{netname}/tinc.conf}, it is recommended to
734 put host specific configuration options in the host configuration file, as this
735 makes it easy to exchange with other nodes.
737 In this section all valid variables are listed in alphabetical order.
738 The default value is given between parentheses,
739 other comments are between square brackets.
742 * Main configuration variables::
743 * Host configuration variables::
749 @c ==================================================================
750 @node Main configuration variables
751 @subsection Main configuration variables
754 @cindex AddressFamily
755 @item AddressFamily = <ipv4|ipv6|any> (any)
756 This option affects the address family of listening and outgoing sockets.
757 If any is selected, then depending on the operating system
758 both IPv4 and IPv6 or just IPv6 listening sockets will be created.
760 @cindex BindToAddress
761 @item BindToAddress = <@var{address}> [experimental]
762 If your computer has more than one IPv4 or IPv6 address, tinc
763 will by default listen on all of them for incoming connections.
764 It is possible to bind only to a single address with this variable.
766 This option may not work on all platforms.
768 @cindex BindToInterface
769 @item BindToInterface = <@var{interface}> [experimental]
770 If you have more than one network interface in your computer, tinc will
771 by default listen on all of them for incoming connections. It is
772 possible to bind tinc to a single interface like eth0 or ppp0 with this
775 This option may not work on all platforms.
778 @item ConnectTo = <@var{name}>
779 Specifies which other tinc daemon to connect to on startup.
780 Multiple ConnectTo variables may be specified,
781 in which case outgoing connections to each specified tinc daemon are made.
782 The names should be known to this tinc daemon
783 (i.e., there should be a host configuration file for the name on the ConnectTo line).
785 If you don't specify a host with ConnectTo,
786 tinc won't try to connect to other daemons at all,
787 and will instead just listen for incoming connections.
790 @item Device = <@var{device}> (@file{/dev/tap0}, @file{/dev/net/tun} or other depending on platform)
791 The virtual network device to use.
792 Tinc will automatically detect what kind of device it is.
793 Note that you can only use one device per daemon.
794 Under Windows, use @var{Interface} instead of @var{Device}.
795 Note that you can only use one device per daemon.
796 See also @ref{Device files}.
799 @item DeviceType = <tun|tunnohead|tunifhead|tap> (only supported on BSD platforms)
800 The type of the virtual network device.
801 Tinc will normally automatically select the right type, and this option should not be used.
802 However, in case tinc does not seem to correctly interpret packets received from the virtual network device,
803 using this option might help.
808 Depending on the platform, this can either be with or without an address family header (see below).
812 Set type to tun without an address family header.
813 Tinc will expect packets read from the virtual network device to start with an IP header.
814 On some platforms IPv6 packets cannot be read from or written to the device in this mode.
818 Set type to tun with an address family header.
819 Tinc will expect packets read from the virtual network device
820 to start with a four byte header containing the address family,
821 followed by an IP header.
822 This mode should support both IPv4 and IPv6 packets.
826 Tinc will expect packets read from the virtual network device
827 to start with an Ethernet header.
831 @item DirectOnly = <yes|no> (no) [experimental]
832 When this option is enabled, packets that cannot be sent directly to the destination node,
833 but which would have to be forwarded by an intermediate node, are dropped instead.
834 When combined with the IndirectData option,
835 packets for nodes for which we do not have a meta connection with are also dropped.
838 @item Forwarding = <off|internal|kernel> (internal) [experimental]
839 This option selects the way indirect packets are forwarded.
843 Incoming packets that are not meant for the local node,
844 but which should be forwarded to another node, are dropped.
847 Incoming packets that are meant for another node are forwarded by tinc internally.
849 This is the default mode, and unless you really know you need another forwarding mode, don't change it.
852 Incoming packets are always sent to the TUN/TAP device, even if the packets are not for the local node.
853 This is less efficient, but allows the kernel to apply its routing and firewall rules on them,
854 and can also help debugging.
857 @cindex GraphDumpFile
858 @item GraphDumpFile = <@var{filename}> [experimental]
859 If this option is present,
860 tinc will dump the current network graph to the file @var{filename}
861 every minute, unless there were no changes to the graph.
862 The file is in a format that can be read by graphviz tools.
863 If @var{filename} starts with a pipe symbol |,
864 then the rest of the filename is interpreted as a shell command
865 that is executed, the graph is then sent to stdin.
868 @item Hostnames = <yes|no> (no)
869 This option selects whether IP addresses (both real and on the VPN)
870 should be resolved. Since DNS lookups are blocking, it might affect
871 tinc's efficiency, even stopping the daemon for a few seconds everytime
872 it does a lookup if your DNS server is not responding.
874 This does not affect resolving hostnames to IP addresses from the
878 @item Interface = <@var{interface}>
879 Defines the name of the interface corresponding to the virtual network device.
880 Depending on the operating system and the type of device this may or may not actually set the name of the interface.
881 Under Windows, this variable is used to select which network interface will be used.
882 If you specified a Device, this variable is almost always already correctly set.
885 @item Mode = <router|switch|hub> (router)
886 This option selects the way packets are routed to other daemons.
892 variables in the host configuration files will be used to form a routing table.
893 Only unicast packets of routable protocols (IPv4 and IPv6) are supported in this mode.
895 This is the default mode, and unless you really know you need another mode, don't change it.
899 In this mode the MAC addresses of the packets on the VPN will be used to
900 dynamically create a routing table just like an Ethernet switch does.
901 Unicast, multicast and broadcast packets of every protocol that runs over Ethernet are supported in this mode
902 at the cost of frequent broadcast ARP requests and routing table updates.
904 This mode is primarily useful if you want to bridge Ethernet segments.
908 This mode is almost the same as the switch mode, but instead
909 every packet will be broadcast to the other daemons
910 while no routing table is managed.
914 @item KeyExpire = <@var{seconds}> (3600)
915 This option controls the time the encryption keys used to encrypt the data
916 are valid. It is common practice to change keys at regular intervals to
917 make it even harder for crackers, even though it is thought to be nearly
918 impossible to crack a single key.
921 @item MACExpire = <@var{seconds}> (600)
922 This option controls the amount of time MAC addresses are kept before they are removed.
923 This only has effect when Mode is set to "switch".
926 @item Name = <@var{name}> [required]
927 This is a symbolic name for this connection.
928 The name should consist only of alfanumeric and underscore characters (a-z, A-Z, 0-9 and _).
931 @item PingInterval = <@var{seconds}> (60)
932 The number of seconds of inactivity that tinc will wait before sending a
933 probe to the other end.
936 @item PingTimeout = <@var{seconds}> (5)
937 The number of seconds to wait for a response to pings or to allow meta
938 connections to block. If the other end doesn't respond within this time,
939 the connection is terminated, and the others will be notified of this.
941 @cindex PriorityInheritance
942 @item PriorityInheritance = <yes|no> (no) [experimental]
943 When this option is enabled the value of the TOS field of tunneled IPv4 packets
944 will be inherited by the UDP packets that are sent out.
947 @item PrivateKey = <@var{key}> [obsolete]
948 This is the RSA private key for tinc. However, for safety reasons it is
949 advised to store private keys of any kind in separate files. This prevents
950 accidental eavesdropping if you are editting the configuration file.
952 @cindex PrivateKeyFile
953 @item PrivateKeyFile = <@var{path}> (@file{@value{sysconfdir}/tinc/@var{netname}/rsa_key.priv})
954 This is the full path name of the RSA private key file that was
955 generated by @samp{tincctl generate-keys}. It must be a full path, not a
958 Note that there must be exactly one of PrivateKey
960 specified in the configuration file.
962 @cindex ProcessPriority
963 @item ProcessPriority = <low|normal|high>
964 When this option is used the priority of the tincd process will be adjusted.
965 Increasing the priority may help to reduce latency and packet loss on the VPN.
967 @cindex StrictSubnets
968 @item StrictSubnets <yes|no> (no) [experimental]
969 When this option is enabled tinc will only use Subnet statements which are
970 present in the host config files in the local
971 @file{@value{sysconfdir}/tinc/@var{netname}/hosts/} directory.
974 @item TunnelServer = <yes|no> (no) [experimental]
975 When this option is enabled tinc will no longer forward information between other tinc daemons,
976 and will only allow connections with nodes for which host config files are present in the local
977 @file{@value{sysconfdir}/tinc/@var{netname}/hosts/} directory.
978 Setting this options also implicitly sets StrictSubnets.
983 @c ==================================================================
984 @node Host configuration variables
985 @subsection Host configuration variables
989 @item Address = <@var{IP address}|@var{hostname}> [<port>] [recommended]
990 This variable is only required if you want to connect to this host. It
991 must resolve to the external IP address where the host can be reached,
992 not the one that is internal to the VPN.
993 If no port is specified, the default Port is used.
996 @item Cipher = <@var{cipher}> (blowfish)
997 The symmetric cipher algorithm used to encrypt UDP packets.
998 Any cipher supported by OpenSSL is recognized.
999 Furthermore, specifying "none" will turn off packet encryption.
1000 It is best to use only those ciphers which support CBC mode.
1003 @item ClampMSS = <yes|no> (yes)
1004 This option specifies whether tinc should clamp the maximum segment size (MSS)
1005 of TCP packets to the path MTU. This helps in situations where ICMP
1006 Fragmentation Needed or Packet too Big messages are dropped by firewalls.
1009 @item Compression = <@var{level}> (0)
1010 This option sets the level of compression used for UDP packets.
1011 Possible values are 0 (off), 1 (fast zlib) and any integer up to 9 (best zlib),
1012 10 (fast lzo) and 11 (best lzo).
1015 @item Digest = <@var{digest}> (sha1)
1016 The digest algorithm used to authenticate UDP packets.
1017 Any digest supported by OpenSSL is recognized.
1018 Furthermore, specifying "none" will turn off packet authentication.
1020 @cindex IndirectData
1021 @item IndirectData = <yes|no> (no)
1022 This option specifies whether other tinc daemons besides the one you
1023 specified with ConnectTo can make a direct connection to you. This is
1024 especially useful if you are behind a firewall and it is impossible to
1025 make a connection from the outside to your tinc daemon. Otherwise, it
1026 is best to leave this option out or set it to no.
1029 @item MACLength = <@var{bytes}> (4)
1030 The length of the message authentication code used to authenticate UDP packets.
1031 Can be anything from 0
1032 up to the length of the digest produced by the digest algorithm.
1035 @item PMTU = <@var{mtu}> (1514)
1036 This option controls the initial path MTU to this node.
1038 @cindex PMTUDiscovery
1039 @item PMTUDiscovery = <yes|no> (yes)
1040 When this option is enabled, tinc will try to discover the path MTU to this node.
1041 After the path MTU has been discovered, it will be enforced on the VPN.
1044 @item Port = <@var{port}> (655)
1045 This is the port this tinc daemon listens on.
1046 You can use decimal portnumbers or symbolic names (as listed in @file{/etc/services}).
1049 @item PublicKey = <@var{key}> [obsolete]
1050 This is the RSA public key for this host.
1052 @cindex PublicKeyFile
1053 @item PublicKeyFile = <@var{path}> [obsolete]
1054 This is the full path name of the RSA public key file that was generated
1055 by @samp{tincctl generate-keys}. It must be a full path, not a relative
1059 From version 1.0pre4 on tinc will store the public key directly into the
1060 host configuration file in PEM format, the above two options then are not
1061 necessary. Either the PEM format is used, or exactly
1062 @strong{one of the above two options} must be specified
1063 in each host configuration file, if you want to be able to establish a
1064 connection with that host.
1067 @item Subnet = <@var{address}[/@var{prefixlength}[#@var{weight}]]>
1068 The subnet which this tinc daemon will serve.
1069 Tinc tries to look up which other daemon it should send a packet to by searching the appropiate subnet.
1070 If the packet matches a subnet,
1071 it will be sent to the daemon who has this subnet in his host configuration file.
1072 Multiple subnet lines can be specified for each daemon.
1074 Subnets can either be single MAC, IPv4 or IPv6 addresses,
1075 in which case a subnet consisting of only that single address is assumed,
1076 or they can be a IPv4 or IPv6 network address with a prefixlength.
1077 Shorthand notations are not supported.
1078 For example, IPv4 subnets must be in a form like 192.168.1.0/24,
1079 where 192.168.1.0 is the network address and 24 is the number of bits set in the netmask.
1080 Note that subnets like 192.168.1.1/24 are invalid!
1081 Read a networking HOWTO/FAQ/guide if you don't understand this.
1082 IPv6 subnets are notated like fec0:0:0:1:0:0:0:0/64.
1083 MAC addresses are notated like 0:1a:2b:3c:4d:5e.
1085 @cindex CIDR notation
1086 Prefixlength is the number of bits set to 1 in the netmask part; for
1087 example: netmask 255.255.255.0 would become /24, 255.255.252.0 becomes
1088 /22. This conforms to standard CIDR notation as described in
1089 @uref{ftp://ftp.isi.edu/in-notes/rfc1519.txt, RFC1519}
1091 A Subnet can be given a weight to indicate its priority over identical Subnets
1092 owned by different nodes. The default weight is 10. Lower values indicate
1093 higher priority. Packets will be sent to the node with the highest priority,
1094 unless that node is not reachable, in which case the node with the next highest
1095 priority will be tried, and so on.
1098 @item TCPonly = <yes|no> (no)
1099 If this variable is set to yes, then the packets are tunnelled over a
1100 TCP connection instead of a UDP connection. This is especially useful
1101 for those who want to run a tinc daemon from behind a masquerading
1102 firewall, or if UDP packet routing is disabled somehow.
1103 Setting this options also implicitly sets IndirectData.
1107 @c ==================================================================
1112 Apart from reading the server and host configuration files,
1113 tinc can also run scripts at certain moments.
1114 Under Windows (not Cygwin), the scripts should have the extension .bat.
1118 @item @value{sysconfdir}/tinc/@var{netname}/tinc-up
1119 This is the most important script.
1120 If it is present it will be executed right after the tinc daemon has been
1121 started and has connected to the virtual network device.
1122 It should be used to set up the corresponding network interface,
1123 but can also be used to start other things.
1124 Under Windows you can use the Network Connections control panel instead of creating this script.
1127 @item @value{sysconfdir}/tinc/@var{netname}/tinc-down
1128 This script is started right before the tinc daemon quits.
1130 @item @value{sysconfdir}/tinc/@var{netname}/hosts/@var{host}-up
1131 This script is started when the tinc daemon with name @var{host} becomes reachable.
1133 @item @value{sysconfdir}/tinc/@var{netname}/hosts/@var{host}-down
1134 This script is started when the tinc daemon with name @var{host} becomes unreachable.
1136 @item @value{sysconfdir}/tinc/@var{netname}/host-up
1137 This script is started when any host becomes reachable.
1139 @item @value{sysconfdir}/tinc/@var{netname}/host-down
1140 This script is started when any host becomes unreachable.
1142 @item @value{sysconfdir}/tinc/@var{netname}/subnet-up
1143 This script is started when a Subnet becomes reachable.
1144 The Subnet and the node it belongs to are passed in environment variables.
1146 @item @value{sysconfdir}/tinc/@var{netname}/subnet-down
1147 This script is started when a Subnet becomes unreachable.
1150 @cindex environment variables
1151 The scripts are started without command line arguments,
1152 but can make use of certain environment variables.
1153 Under UNIX like operating systems the names of environment variables must be preceded by a $ in scripts.
1154 Under Windows, in @file{.bat} files, they have to be put between % signs.
1159 If a netname was specified, this environment variable contains it.
1163 Contains the name of this tinc daemon.
1167 Contains the name of the virtual network device that tinc uses.
1171 Contains the name of the virtual network interface that tinc uses.
1172 This should be used for commands like ifconfig.
1176 When a host becomes (un)reachable, this is set to its name.
1177 If a subnet becomes (un)reachable, this is set to the owner of that subnet.
1179 @cindex REMOTEADDRESS
1181 When a host becomes (un)reachable, this is set to its real address.
1185 When a host becomes (un)reachable,
1186 this is set to the port number it uses for communication with other tinc daemons.
1190 When a subnet becomes (un)reachable, this is set to the subnet.
1195 @c ==================================================================
1196 @node How to configure
1197 @subsection How to configure
1199 @subsubheading Step 1. Creating the main configuration file
1201 The main configuration file will be called @file{@value{sysconfdir}/tinc/@var{netname}/tinc.conf}.
1202 Adapt the following example to create a basic configuration file:
1205 Name = @var{yourname}
1206 Device = @file{/dev/tap0}
1209 Then, if you know to which other tinc daemon(s) yours is going to connect,
1210 add `ConnectTo' values.
1212 @subsubheading Step 2. Creating your host configuration file
1214 If you added a line containing `Name = yourname' in the main configuarion file,
1215 you will need to create a host configuration file @file{@value{sysconfdir}/tinc/@var{netname}/hosts/yourname}.
1216 Adapt the following example to create a host configuration file:
1219 Address = your.real.hostname.org
1220 Subnet = 192.168.1.0/24
1223 You can also use an IP address instead of a hostname.
1224 The `Subnet' specifies the address range that is local for @emph{your part of the VPN only}.
1225 If you have multiple address ranges you can specify more than one `Subnet'.
1226 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).
1229 @c ==================================================================
1230 @node Generating keypairs
1231 @section Generating keypairs
1233 @cindex key generation
1234 Now that you have already created the main configuration file and your host configuration file,
1235 you can easily create a public/private keypair by entering the following command:
1238 tincctl -n @var{netname} generate-keys
1241 Tinc will generate a public and a private key and ask you where to put them.
1242 Just press enter to accept the defaults.
1245 @c ==================================================================
1246 @node Network interfaces
1247 @section Network interfaces
1249 Before tinc can start transmitting data over the tunnel, it must
1250 set up the virtual network interface.
1252 First, decide which IP addresses you want to have associated with these
1253 devices, and what network mask they must have.
1255 Tinc will open a virtual network device (@file{/dev/tun}, @file{/dev/tap0} or similar),
1256 which will also create a network interface called something like @samp{tun0}, @samp{tap0}.
1257 If you are using the Linux tun/tap driver, the network interface will by default have the same name as the @var{netname}.
1258 Under Windows you can change the name of the network interface from the Network Connections control panel.
1261 You can configure the network interface by putting ordinary ifconfig, route, and other commands
1262 to a script named @file{@value{sysconfdir}/tinc/@var{netname}/tinc-up}.
1263 When tinc starts, this script will be executed. When tinc exits, it will execute the script named
1264 @file{@value{sysconfdir}/tinc/@var{netname}/tinc-down}, but normally you don't need to create that script.
1266 An example @file{tinc-up} script:
1270 ifconfig $INTERFACE 192.168.1.1 netmask 255.255.0.0
1273 This script gives the interface an IP address and a netmask.
1274 The kernel will also automatically add a route to this interface, so normally you don't need
1275 to add route commands to the @file{tinc-up} script.
1276 The kernel will also bring the interface up after this command.
1278 The netmask is the mask of the @emph{entire} VPN network, not just your
1281 The exact syntax of the ifconfig and route commands differs from platform to platform.
1282 You can look up the commands for setting addresses and adding routes in @ref{Platform specific information},
1283 but it is best to consult the manpages of those utilities on your platform.
1286 @c ==================================================================
1287 @node Example configuration
1288 @section Example configuration
1292 Imagine the following situation. Branch A of our example `company' wants to connect
1293 three branch offices in B, C and D using the Internet. All four offices
1294 have a 24/7 connection to the Internet.
1296 A is going to serve as the center of the network. B and C will connect
1297 to A, and D will connect to C. Each office will be assigned their own IP
1301 A: net 10.1.0.0 mask 255.255.0.0 gateway 10.1.54.1 internet IP 1.2.3.4
1302 B: net 10.2.0.0 mask 255.255.0.0 gateway 10.2.1.12 internet IP 2.3.4.5
1303 C: net 10.3.0.0 mask 255.255.0.0 gateway 10.3.69.254 internet IP 3.4.5.6
1304 D: net 10.4.0.0 mask 255.255.0.0 gateway 10.4.3.32 internet IP 4.5.6.7
1307 Here, ``gateway'' is the VPN IP address of the machine that is running the
1308 tincd, and ``internet IP'' is the IP address of the firewall, which does not
1309 need to run tincd, but it must do a port forwarding of TCP and UDP on port
1310 655 (unless otherwise configured).
1312 In this example, it is assumed that eth0 is the interface that points to
1313 the inner (physical) LAN of the office, although this could also be the
1314 same as the interface that leads to the Internet. The configuration of
1315 the real interface is also shown as a comment, to give you an idea of
1316 how these example host is set up. All branches use the netname `company'
1317 for this particular VPN.
1319 @subsubheading For Branch A
1321 @emph{BranchA} would be configured like this:
1323 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1326 # Real interface of internal network:
1327 # ifconfig eth0 10.1.54.1 netmask 255.255.0.0
1329 ifconfig $INTERFACE 10.1.54.1 netmask 255.0.0.0
1332 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1339 On all hosts, @file{@value{sysconfdir}/tinc/company/hosts/BranchA} contains:
1342 Subnet = 10.1.0.0/16
1345 -----BEGIN RSA PUBLIC KEY-----
1347 -----END RSA PUBLIC KEY-----
1350 Note that the IP addresses of eth0 and tap0 are the same.
1351 This is quite possible, if you make sure that the netmasks of the interfaces are different.
1352 It is in fact recommended to give both real internal network interfaces and tap interfaces the same IP address,
1353 since that will make things a lot easier to remember and set up.
1356 @subsubheading For Branch B
1358 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1361 # Real interface of internal network:
1362 # ifconfig eth0 10.2.43.8 netmask 255.255.0.0
1364 ifconfig $INTERFACE 10.2.1.12 netmask 255.0.0.0
1367 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1374 Note here that the internal address (on eth0) doesn't have to be the
1375 same as on the tap0 device. Also, ConnectTo is given so that this node will
1376 always try to connect to BranchA.
1378 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchB}:
1381 Subnet = 10.2.0.0/16
1384 -----BEGIN RSA PUBLIC KEY-----
1386 -----END RSA PUBLIC KEY-----
1390 @subsubheading For Branch C
1392 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1395 # Real interface of internal network:
1396 # ifconfig eth0 10.3.69.254 netmask 255.255.0.0
1398 ifconfig $INTERFACE 10.3.69.254 netmask 255.0.0.0
1401 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1409 C already has another daemon that runs on port 655, so they have to
1410 reserve another port for tinc. It knows the portnumber it has to listen on
1411 from it's own host configuration file.
1413 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchC}:
1417 Subnet = 10.3.0.0/16
1420 -----BEGIN RSA PUBLIC KEY-----
1422 -----END RSA PUBLIC KEY-----
1426 @subsubheading For Branch D
1428 In @file{@value{sysconfdir}/tinc/company/tinc-up}:
1431 # Real interface of internal network:
1432 # ifconfig eth0 10.4.3.32 netmask 255.255.0.0
1434 ifconfig $INTERFACE 10.4.3.32 netmask 255.0.0.0
1437 and in @file{@value{sysconfdir}/tinc/company/tinc.conf}:
1442 Device = /dev/net/tun
1445 D will be connecting to C, which has a tincd running for this network on
1446 port 2000. It knows the port number from the host configuration file.
1447 Also note that since D uses the tun/tap driver, the network interface
1448 will not be called `tun' or `tap0' or something like that, but will
1449 have the same name as netname.
1451 On all hosts, in @file{@value{sysconfdir}/tinc/company/hosts/BranchD}:
1454 Subnet = 10.4.0.0/16
1457 -----BEGIN RSA PUBLIC KEY-----
1459 -----END RSA PUBLIC KEY-----
1462 @subsubheading Key files
1464 A, B, C and D all have generated a public/private keypair with the following command:
1467 tincctl -n company generate-keys
1470 The private key is stored in @file{@value{sysconfdir}/tinc/company/rsa_key.priv},
1471 the public key is put into the host configuration file in the @file{@value{sysconfdir}/tinc/company/hosts/} directory.
1472 During key generation, tinc automatically guesses the right filenames based on the -n option and
1473 the Name directive in the @file{tinc.conf} file (if it is available).
1475 @subsubheading Starting
1477 After each branch has finished configuration and they have distributed
1478 the host configuration files amongst them, they can start their tinc daemons.
1479 They don't necessarily have to wait for the other branches to have started
1480 their daemons, tinc will try connecting until they are available.
1483 @c ==================================================================
1485 @chapter Running tinc
1487 If everything else is done, you can start tinc by typing the following command:
1490 tincd -n @var{netname}
1494 Tinc will detach from the terminal and continue to run in the background like a good daemon.
1495 If there are any problems however you can try to increase the debug level
1496 and look in the syslog to find out what the problems are.
1502 * Solving problems::
1504 * Sending bug reports::
1508 @c ==================================================================
1509 @node Runtime options
1510 @section Runtime options
1512 Besides the settings in the configuration file, tinc also accepts some
1513 command line options.
1515 @cindex command line
1516 @cindex runtime options
1520 @item -c, --config=@var{path}
1521 Read configuration options from the directory @var{path}. The default is
1522 @file{@value{sysconfdir}/tinc/@var{netname}/}.
1524 @item -D, --no-detach
1525 Don't fork and detach.
1526 This will also disable the automatic restart mechanism for fatal errors.
1529 @item -d, --debug=@var{level}
1530 Set debug level to @var{level}. The higher the debug level, the more gets
1531 logged. Everything goes via syslog.
1533 @item -n, --net=@var{netname}
1534 Use configuration for net @var{netname}. @xref{Multiple networks}.
1536 @item --controlsocket=@var{filename}
1537 Open control socket at @var{filename}. If unspecified, the default is
1538 @file{@value{localstatedir}/run/tinc.@var{netname}.control}.
1541 Lock tinc into main memory.
1542 This will prevent sensitive data like shared private keys to be written to the system swap files/partitions.
1544 @item --logfile[=@var{file}]
1545 Write log entries to a file instead of to the system logging facility.
1546 If @var{file} is omitted, the default is @file{@value{localstatedir}/log/tinc.@var{netname}.log}.
1548 @item --bypass-security
1549 Disables encryption and authentication.
1550 Only useful for debugging.
1553 Change process root directory to the directory where the config file is
1554 located (@file{@value{sysconfdir}/tinc/@var{netname}/} as determined by
1555 -n/--net option or as given by -c/--config option), for added security.
1556 The chroot is performed after all the initialization is done, after
1557 writing pid files and opening network sockets.
1559 Note that this option alone does not do any good without -U/--user, below.
1561 Note also that tinc can't run scripts anymore (such as tinc-down or host-up),
1562 unless it's setup to be runnable inside chroot environment.
1564 @item -U, --user=@var{user}
1565 Switch to the given @var{user} after initialization, at the same time as
1566 chroot is performed (see --chroot above). With this option tinc drops
1567 privileges, for added security.
1570 Display a short reminder of these runtime options and terminate.
1573 Output version information and exit.
1577 @c ==================================================================
1582 You can also send the following signals to a running tincd process:
1588 Partially rereads configuration files.
1589 Connections to hosts whose host config file are removed are closed.
1590 New outgoing connections specified in @file{tinc.conf} will be made.
1594 @c ==================================================================
1596 @section Debug levels
1598 @cindex debug levels
1599 The tinc daemon can send a lot of messages to the syslog.
1600 The higher the debug level, the more messages it will log.
1601 Each level inherits all messages of the previous level:
1607 This will log a message indicating tinc has started along with a version number.
1608 It will also log any serious error.
1611 This will log all connections that are made with other tinc daemons.
1614 This will log status and error messages from scripts and other tinc daemons.
1617 This will log all requests that are exchanged with other tinc daemons. These include
1618 authentication, key exchange and connection list updates.
1621 This will log a copy of everything received on the meta socket.
1624 This will log all network traffic over the virtual private network.
1628 @c ==================================================================
1629 @node Solving problems
1630 @section Solving problems
1632 If tinc starts without problems, but if the VPN doesn't work, you will have to find the cause of the problem.
1633 The first thing to do is to start tinc with a high debug level in the foreground,
1634 so you can directly see everything tinc logs:
1637 tincd -n @var{netname} -d5 -D
1640 If tinc does not log any error messages, then you might want to check the following things:
1643 @item @file{tinc-up} script
1644 Does this script contain the right commands?
1645 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.
1648 Does the Subnet (or Subnets) in the host configuration file of this host match the portion of the VPN that belongs to this host?
1650 @item Firewalls and NATs
1651 Do you have a firewall or a NAT device (a masquerading firewall or perhaps an ADSL router that performs masquerading)?
1652 If so, check that it allows TCP and UDP traffic on port 655.
1653 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.
1654 You can add @samp{TCPOnly = yes} to your host config file to force tinc to only use a single TCP connection,
1655 this works through most firewalls and NATs.
1660 @c ==================================================================
1661 @node Error messages
1662 @section Error messages
1664 What follows is a list of the most common error messages you might find in the logs.
1665 Some of them will only be visible if the debug level is high enough.
1668 @item Could not open /dev/tap0: No such device
1671 @item You forgot to `modprobe netlink_dev' or `modprobe ethertap'.
1672 @item You forgot to compile `Netlink device emulation' in the kernel.
1675 @item Can't write to /dev/net/tun: No such device
1678 @item You forgot to `modprobe tun'.
1679 @item You forgot to compile `Universal TUN/TAP driver' in the kernel.
1680 @item The tun device is located somewhere else in @file{/dev/}.
1683 @item Network address and prefix length do not match!
1686 @item The Subnet field must contain a @emph{network} address, trailing bits should be 0.
1687 @item If you only want to use one IP address, set the netmask to /32.
1690 @item Error reading RSA key file `rsa_key.priv': No such file or directory
1693 @item You forgot to create a public/private keypair.
1694 @item Specify the complete pathname to the private key file with the @samp{PrivateKeyFile} option.
1697 @item Warning: insecure file permissions for RSA private key file `rsa_key.priv'!
1700 @item The private key file is readable by users other than root.
1701 Use chmod to correct the file permissions.
1704 @item Creating metasocket failed: Address family not supported
1707 @item By default tinc tries to create both IPv4 and IPv6 sockets.
1708 On some platforms this might not be implemented.
1709 If the logs show @samp{Ready} later on, then at least one metasocket was created,
1710 and you can ignore this message.
1711 You can add @samp{AddressFamily = ipv4} to @file{tinc.conf} to prevent this from happening.
1714 @item Cannot route packet: unknown IPv4 destination 1.2.3.4
1717 @item You try to send traffic to a host on the VPN for which no Subnet is known.
1718 @item If it is a broadcast address (ending in .255), it probably is a samba server or a Windows host sending broadcast packets.
1722 @item Cannot route packet: ARP request for unknown address 1.2.3.4
1725 @item You try to send traffic to a host on the VPN for which no Subnet is known.
1728 @item Packet with destination 1.2.3.4 is looping back to us!
1731 @item Something is not configured right. Packets are being sent out to the
1732 virtual network device, but according to the Subnet directives in your host configuration
1733 file, those packets should go to your own host. Most common mistake is that
1734 you have a Subnet line in your host configuration file with a prefix length which is
1735 just as large as the prefix of the virtual network interface. The latter should in almost all
1736 cases be larger. Rethink your configuration.
1737 Note that you will only see this message if you specified a debug
1738 level of 5 or higher!
1739 @item Chances are that a @samp{Subnet = ...} line in the host configuration file of this tinc daemon is wrong.
1740 Change it to a subnet that is accepted locally by another interface,
1741 or if that is not the case, try changing the prefix length into /32.
1744 @item Node foo (1.2.3.4) is not reachable
1747 @item Node foo does not have a connection anymore, its tinc daemon is not running or its connection to the Internet is broken.
1750 @item Received UDP packet from unknown source 1.2.3.4 (port 12345)
1753 @item If you see this only sporadically, it is harmless and caused by a node sending packets using an old key.
1754 @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.
1755 You can add @samp{TCPOnly = yes} to host configuration files to force all VPN traffic to go over a TCP connection.
1758 @item Got bad/bogus/unauthorized REQUEST from foo (1.2.3.4 port 12345)
1761 @item Node foo does not have the right public/private keypair.
1762 Generate new keypairs and distribute them again.
1763 @item An attacker tries to gain access to your VPN.
1764 @item A network error caused corruption of metadata sent from foo.
1769 @c ==================================================================
1770 @node Sending bug reports
1771 @section Sending bug reports
1773 If you really can't find the cause of a problem, or if you suspect tinc is not working right,
1774 you can send us a bugreport, see @ref{Contact information}.
1775 Be sure to include the following information in your bugreport:
1778 @item A clear description of what you are trying to achieve and what the problem is.
1779 @item What platform (operating system, version, hardware architecture) and which version of tinc you use.
1780 @item If compiling tinc fails, a copy of @file{config.log} and the error messages you get.
1781 @item Otherwise, a copy of @file{tinc.conf}, @file{tinc-up} and all files in the @file{hosts/} directory.
1782 @item The output of the commands @samp{ifconfig -a} and @samp{route -n} (or @samp{netstat -rn} if that doesn't work).
1783 @item The output of any command that fails to work as it should (like ping or traceroute).
1786 @c ==================================================================
1787 @node Controlling tinc
1788 @chapter Controlling tinc
1790 You can control and inspect a running @samp{tincd} through the @samp{tincctl}
1791 command. A quick example:
1794 tincctl -n @var{netname} reload
1798 * tincctl runtime options::
1799 * tincctl commands::
1803 @c ==================================================================
1804 @node tincctl runtime options
1805 @section tincctl runtime options
1809 @item -c, --config=@var{path}
1810 Read configuration options from the directory @var{path}. The default is
1811 @file{@value{sysconfdir}/tinc/@var{netname}/}.
1813 @item -n, --net=@var{netname}
1814 Use configuration for net @var{netname}. @xref{Multiple networks}.
1816 @item --controlsocket=@var{filename}
1817 Open control socket at @var{filename}. If unspecified, the default is
1818 @file{@value{localstatedir}/run/tinc.@var{netname}.control}.
1821 Display a short reminder of runtime options and commands, then terminate.
1824 Output version information and exit.
1829 @c ==================================================================
1830 @node tincctl commands
1831 @section tincctl commands
1843 Restart @samp{tincd}.
1846 Partially rereads configuration files. Connections to hosts whose host
1847 config files are removed are closed. New outgoing connections specified
1848 in @file{tinc.conf} will be made.
1851 Shows the PID of the currently running @samp{tincd}.
1853 @item generate-keys [@var{bits}]
1854 Generate public/private keypair of @var{bits} length. If @var{bits} is not specified,
1855 1024 is the default. tinc will ask where you want to store the files,
1856 but will default to the configuration directory (you can use the -c or -n
1860 Dump a list of all known nodes in the VPN.
1863 Dump a list of all known connections in the VPN.
1866 Dump a list of all known subnets in the VPN.
1868 @item dump connections
1869 Dump a list of all meta connections with ourself.
1872 Dump a graph of the VPN in dotty format.
1875 Purges all information remembered about unreachable nodes.
1877 @item debug @var{level}
1878 Sets debug level to @var{level}.
1881 Forces tinc to try to connect to all uplinks immediately.
1882 Usually tinc attempts to do this itself,
1883 but increases the time it waits between the attempts each time it failed,
1884 and if tinc didn't succeed to connect to an uplink the first time after it started,
1885 it defaults to the maximum time of 15 minutes.
1890 @c ==================================================================
1891 @node Technical information
1892 @chapter Technical information
1897 * The meta-protocol::
1902 @c ==================================================================
1903 @node The connection
1904 @section The connection
1907 Tinc is a daemon that takes VPN data and transmit that to another host
1908 computer over the existing Internet infrastructure.
1912 * The meta-connection::
1916 @c ==================================================================
1917 @node The UDP tunnel
1918 @subsection The UDP tunnel
1920 @cindex virtual network device
1922 The data itself is read from a character device file, the so-called
1923 @emph{virtual network device}. This device is associated with a network
1924 interface. Any data sent to this interface can be read from the device,
1925 and any data written to the device gets sent from the interface.
1926 There are two possible types of virtual network devices:
1927 `tun' style, which are point-to-point devices which can only handle IPv4 and/or IPv6 packets,
1928 and `tap' style, which are Ethernet devices and handle complete Ethernet frames.
1930 So when tinc reads an Ethernet frame from the device, it determines its
1931 type. When tinc is in it's default routing mode, it can handle IPv4 and IPv6
1932 packets. Depending on the Subnet lines, it will send the packets off to their destination IP address.
1933 In the `switch' and `hub' mode, tinc will use broadcasts and MAC address discovery
1934 to deduce the destination of the packets.
1935 Since the latter modes only depend on the link layer information,
1936 any protocol that runs over Ethernet is supported (for instance IPX and Appletalk).
1937 However, only `tap' style devices provide this information.
1939 After the destination has been determined,
1940 the packet will be compressed (optionally),
1941 a sequence number will be added to the packet,
1942 the packet will then be encrypted
1943 and a message authentication code will be appended.
1945 @cindex encapsulating
1947 When that is done, time has come to actually transport the
1948 packet to the destination computer. We do this by sending the packet
1949 over an UDP connection to the destination host. This is called
1950 @emph{encapsulating}, the VPN packet (though now encrypted) is
1951 encapsulated in another IP datagram.
1953 When the destination receives this packet, the same thing happens, only
1954 in reverse. So it checks the message authentication code, decrypts the contents of the UDP datagram,
1955 checks the sequence number
1956 and writes the decrypted information to its own virtual network device.
1958 If the virtual network device is a `tun' device (a point-to-point tunnel),
1959 there is no problem for the kernel to accept a packet.
1960 However, if it is a `tap' device (this is the only available type on FreeBSD),
1961 the destination MAC address must match that of the virtual network interface.
1962 If tinc is in it's default routing mode, ARP does not work, so the correct destination MAC
1963 can not be known by the sending host.
1964 Tinc solves this by letting the receiving end detect the MAC address of its own virtual network interface
1965 and overwriting the destination MAC address of the received packet.
1967 In switch or hub modes ARP does work so the sender already knows the correct destination MAC address.
1968 In those modes every interface should have a unique MAC address, so make sure they are not the same.
1969 Because switch and hub modes rely on MAC addresses to function correctly,
1970 these modes cannot be used on the following operating systems which don't have a `tap' style virtual network device:
1971 OpenBSD, NetBSD, Darwin and Solaris.
1974 @c ==================================================================
1975 @node The meta-connection
1976 @subsection The meta-connection
1978 Having only a UDP connection available is not enough. Though suitable
1979 for transmitting data, we want to be able to reliably send other
1980 information, such as routing and session key information to somebody.
1983 TCP is a better alternative, because it already contains protection
1984 against information being lost, unlike UDP.
1986 So we establish two connections. One for the encrypted VPN data, and one
1987 for other information, the meta-data. Hence, we call the second
1988 connection the meta-connection. We can now be sure that the
1989 meta-information doesn't get lost on the way to another computer.
1991 @cindex data-protocol
1992 @cindex meta-protocol
1993 Like with any communication, we must have a protocol, so that everybody
1994 knows what everything stands for, and how she should react. Because we
1995 have two connections, we also have two protocols. The protocol used for
1996 the UDP data is the ``data-protocol,'' the other one is the
1999 The reason we don't use TCP for both protocols is that UDP is much
2000 better for encapsulation, even while it is less reliable. The real
2001 problem is that when TCP would be used to encapsulate a TCP stream
2002 that's on the private network, for every packet sent there would be
2003 three ACKs sent instead of just one. Furthermore, if there would be
2004 a timeout, both TCP streams would sense the timeout, and both would
2005 start re-sending packets.
2008 @c ==================================================================
2009 @node The meta-protocol
2010 @section The meta-protocol
2012 The meta protocol is used to tie all tinc daemons together, and
2013 exchange information about which tinc daemon serves which virtual
2016 The meta protocol consists of requests that can be sent to the other
2017 side. Each request has a unique number and several parameters. All
2018 requests are represented in the standard ASCII character set. It is
2019 possible to use tools such as telnet or netcat to connect to a tinc
2020 daemon started with the --bypass-security option
2021 and to read and write requests by hand, provided that one
2022 understands the numeric codes sent.
2024 The authentication scheme is described in @ref{Authentication protocol}. After a
2025 successful authentication, the server and the client will exchange all the
2026 information about other tinc daemons and subnets they know of, so that both
2027 sides (and all the other tinc daemons behind them) have their information
2034 ------------------------------------------------------------------
2035 ADD_EDGE node1 node2 21.32.43.54 655 222 0
2036 | | | | | +-> options
2037 | | | | +----> weight
2038 | | | +--------> UDP port of node2
2039 | | +----------------> real address of node2
2040 | +-------------------------> name of destination node
2041 +-------------------------------> name of source node
2043 ADD_SUBNET node 192.168.1.0/24
2044 | | +--> prefixlength
2045 | +--------> network address
2046 +------------------> owner of this subnet
2047 ------------------------------------------------------------------
2050 The ADD_EDGE messages are to inform other tinc daemons that a connection between
2051 two nodes exist. The address of the destination node is available so that
2052 VPN packets can be sent directly to that node.
2054 The ADD_SUBNET messages inform other tinc daemons that certain subnets belong
2055 to certain nodes. tinc will use it to determine to which node a VPN packet has
2062 ------------------------------------------------------------------
2063 DEL_EDGE node1 node2
2064 | +----> name of destination node
2065 +----------> name of source node
2067 DEL_SUBNET node 192.168.1.0/24
2068 | | +--> prefixlength
2069 | +--------> network address
2070 +------------------> owner of this subnet
2071 ------------------------------------------------------------------
2074 In case a connection between two daemons is closed or broken, DEL_EDGE messages
2075 are sent to inform the other daemons of that fact. Each daemon will calculate a
2076 new route to the the daemons, or mark them unreachable if there isn't any.
2083 ------------------------------------------------------------------
2084 REQ_KEY origin destination
2085 | +--> name of the tinc daemon it wants the key from
2086 +----------> name of the daemon that wants the key
2088 ANS_KEY origin destination 4ae0b0a82d6e0078 91 64 4
2089 | | \______________/ | | +--> MAC length
2090 | | | | +-----> digest algorithm
2091 | | | +--------> cipher algorithm
2092 | | +--> 128 bits key
2093 | +--> name of the daemon that wants the key
2094 +----------> name of the daemon that uses this key
2097 +--> daemon that has changed it's packet key
2098 ------------------------------------------------------------------
2101 The keys used to encrypt VPN packets are not sent out directly. This is
2102 because it would generate a lot of traffic on VPNs with many daemons, and
2103 chances are that not every tinc daemon will ever send a packet to every
2104 other daemon. Instead, if a daemon needs a key it sends a request for it
2105 via the meta connection of the nearest hop in the direction of the
2112 ------------------------------------------------------------------
2115 ------------------------------------------------------------------
2118 There is also a mechanism to check if hosts are still alive. Since network
2119 failures or a crash can cause a daemon to be killed without properly
2120 shutting down the TCP connection, this is necessary to keep an up to date
2121 connection list. PINGs are sent at regular intervals, except when there
2122 is also some other traffic. A little bit of salt (random data) is added
2123 with each PING and PONG message, to make sure that long sequences of PING/PONG
2124 messages without any other traffic won't result in known plaintext.
2126 This basically covers what is sent over the meta connection by tinc.
2129 @c ==================================================================
2135 Tinc got its name from ``TINC,'' short for @emph{There Is No Cabal}; the
2136 alleged Cabal was/is an organisation that was said to keep an eye on the
2137 entire Internet. As this is exactly what you @emph{don't} want, we named
2138 the tinc project after TINC.
2141 But in order to be ``immune'' to eavesdropping, you'll have to encrypt
2142 your data. Because tinc is a @emph{Secure} VPN (SVPN) daemon, it does
2143 exactly that: encrypt.
2144 Tinc by default uses blowfish encryption with 128 bit keys in CBC mode, 32 bit
2145 sequence numbers and 4 byte long message authentication codes to make sure
2146 eavesdroppers cannot get and cannot change any information at all from the
2147 packets they can intercept. The encryption algorithm and message authentication
2148 algorithm can be changed in the configuration. The length of the message
2149 authentication codes is also adjustable. The length of the key for the
2150 encryption algorithm is always the default length used by OpenSSL.
2153 * Authentication protocol::
2154 * Encryption of network packets::
2159 @c ==================================================================
2160 @node Authentication protocol
2161 @subsection Authentication protocol
2163 @cindex authentication
2164 A new scheme for authentication in tinc has been devised, which offers some
2165 improvements over the protocol used in 1.0pre2 and 1.0pre3. Explanation is
2175 --------------------------------------------------------------------------
2176 client <attempts connection>
2178 server <accepts connection>
2182 +-------> name of tinc daemon
2186 +-------> name of tinc daemon
2188 client META_KEY 5f0823a93e35b69e...7086ec7866ce582b
2189 \_________________________________/
2190 +-> RSAKEYLEN bits totally random string S1,
2191 encrypted with server's public RSA key
2193 server META_KEY 6ab9c1640388f8f0...45d1a07f8a672630
2194 \_________________________________/
2195 +-> RSAKEYLEN bits totally random string S2,
2196 encrypted with client's public RSA key
2199 - the client will symmetrically encrypt outgoing traffic using S1
2200 - the server will symmetrically encrypt outgoing traffic using S2
2202 client CHALLENGE da02add1817c1920989ba6ae2a49cecbda0
2203 \_________________________________/
2204 +-> CHALLEN bits totally random string H1
2206 server CHALLENGE 57fb4b2ccd70d6bb35a64c142f47e61d57f
2207 \_________________________________/
2208 +-> CHALLEN bits totally random string H2
2210 client CHAL_REPLY 816a86
2211 +-> 160 bits SHA1 of H2
2213 server CHAL_REPLY 928ffe
2214 +-> 160 bits SHA1 of H1
2216 After the correct challenge replies are received, both ends have proved
2217 their identity. Further information is exchanged.
2219 client ACK 655 123 0
2221 | +----> estimated weight
2222 +--------> listening port of client
2224 server ACK 655 321 0
2226 | +----> estimated weight
2227 +--------> listening port of server
2228 --------------------------------------------------------------------------
2231 This new scheme has several improvements, both in efficiency and security.
2233 First of all, the server sends exactly the same kind of messages over the wire
2234 as the client. The previous versions of tinc first authenticated the client,
2235 and then the server. This scheme even allows both sides to send their messages
2236 simultaneously, there is no need to wait for the other to send something first.
2237 This means that any calculations that need to be done upon sending or receiving
2238 a message can also be done in parallel. This is especially important when doing
2239 RSA encryption/decryption. Given that these calculations are the main part of
2240 the CPU time spent for the authentication, speed is improved by a factor 2.
2242 Second, only one RSA encrypted message is sent instead of two. This reduces the
2243 amount of information attackers can see (and thus use for a cryptographic
2244 attack). It also improves speed by a factor two, making the total speedup a
2247 Third, and most important:
2248 The symmetric cipher keys are exchanged first, the challenge is done
2249 afterwards. In the previous authentication scheme, because a man-in-the-middle
2250 could pass the challenge/chal_reply phase (by just copying the messages between
2251 the two real tinc daemons), but no information was exchanged that was really
2252 needed to read the rest of the messages, the challenge/chal_reply phase was of
2253 no real use. The man-in-the-middle was only stopped by the fact that only after
2254 the ACK messages were encrypted with the symmetric cipher. Potentially, it
2255 could even send it's own symmetric key to the server (if it knew the server's
2256 public key) and read some of the metadata the server would send it (it was
2257 impossible for the mitm to read actual network packets though). The new scheme
2258 however prevents this.
2260 This new scheme makes sure that first of all, symmetric keys are exchanged. The
2261 rest of the messages are then encrypted with the symmetric cipher. Then, each
2262 side can only read received messages if they have their private key. The
2263 challenge is there to let the other side know that the private key is really
2264 known, because a challenge reply can only be sent back if the challenge is
2265 decrypted correctly, and that can only be done with knowledge of the private
2268 Fourth: the first thing that is sent via the symmetric cipher encrypted
2269 connection is a totally random string, so that there is no known plaintext (for
2270 an attacker) in the beginning of the encrypted stream.
2273 @c ==================================================================
2274 @node Encryption of network packets
2275 @subsection Encryption of network packets
2278 A data packet can only be sent if the encryption key is known to both
2279 parties, and the connection is activated. If the encryption key is not
2280 known, a request is sent to the destination using the meta connection
2281 to retrieve it. The packet is stored in a queue while waiting for the
2285 The UDP packet containing the network packet from the VPN has the following layout:
2288 ... | IP header | UDP header | seqno | VPN packet | MAC | UDP trailer
2289 \___________________/\_____/
2291 V +---> digest algorithm
2292 Encrypted with symmetric cipher
2295 So, the entire VPN packet is encrypted using a symmetric cipher, including a 32 bits
2296 sequence number that is added in front of the actual VPN packet, to act as a unique
2297 IV for each packet and to prevent replay attacks. A message authentication code
2298 is added to the UDP packet to prevent alteration of packets. By default the
2299 first 4 bytes of the digest are used for this, but this can be changed using
2300 the MACLength configuration variable.
2302 @c ==================================================================
2303 @node Security issues
2304 @subsection Security issues
2306 In August 2000, we discovered the existence of a security hole in all versions
2307 of tinc up to and including 1.0pre2. This had to do with the way we exchanged
2308 keys. Since then, we have been working on a new authentication scheme to make
2309 tinc as secure as possible. The current version uses the OpenSSL library and
2310 uses strong authentication with RSA keys.
2312 On the 29th of December 2001, Jerome Etienne posted a security analysis of tinc
2313 1.0pre4. Due to a lack of sequence numbers and a message authentication code
2314 for each packet, an attacker could possibly disrupt certain network services or
2315 launch a denial of service attack by replaying intercepted packets. The current
2316 version adds sequence numbers and message authentication codes to prevent such
2319 On the 15th of September 2003, Peter Gutmann posted a security analysis of tinc
2320 1.0.1. He argues that the 32 bit sequence number used by tinc is not a good IV,
2321 that tinc's default length of 4 bytes for the MAC is too short, and he doesn't
2322 like tinc's use of RSA during authentication. We do not know of a security hole
2323 in this version of tinc, but tinc's security is not as strong as TLS or IPsec.
2324 We will address these issues in tinc 2.0.
2326 Cryptography is a hard thing to get right. We cannot make any
2327 guarantees. Time, review and feedback are the only things that can
2328 prove the security of any cryptographic product. If you wish to review
2329 tinc or give us feedback, you are stronly encouraged to do so.
2332 @c ==================================================================
2333 @node Platform specific information
2334 @chapter Platform specific information
2337 * Interface configuration::
2341 @c ==================================================================
2342 @node Interface configuration
2343 @section Interface configuration
2345 When configuring an interface, one normally assigns it an address and a
2346 netmask. The address uniquely identifies the host on the network attached to
2347 the interface. The netmask, combined with the address, forms a subnet. It is
2348 used to add a route to the routing table instructing the kernel to send all
2349 packets which fall into that subnet to that interface. Because all packets for
2350 the entire VPN should go to the virtual network interface used by tinc, the
2351 netmask should be such that it encompasses the entire VPN.
2355 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2357 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2358 @item Linux iproute2
2359 @tab @code{ip addr add} @var{address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2361 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2363 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2365 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2367 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2368 @item Darwin (MacOS/X)
2369 @tab @code{ifconfig} @var{interface} @var{address} @code{netmask} @var{netmask}
2371 @tab @code{netsh interface ip set address} @var{interface} @code{static} @var{address} @var{netmask}
2377 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2379 @tab @code{ifconfig} @var{interface} @code{add} @var{address}@code{/}@var{prefixlength}
2381 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2383 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2385 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2387 @tab @code{ifconfig} @var{interface} @code{inet6 plumb up}
2389 @tab @code{ifconfig} @var{interface} @code{inet6 addif} @var{address} @var{address}
2390 @item Darwin (MacOS/X)
2391 @tab @code{ifconfig} @var{interface} @code{inet6} @var{address} @code{prefixlen} @var{prefixlength}
2393 @tab @code{netsh interface ipv6 add address} @var{interface} @code{static} @var{address}/@var{prefixlength}
2397 @c ==================================================================
2401 In some cases it might be necessary to add more routes to the virtual network
2402 interface. There are two ways to indicate which interface a packet should go
2403 to, one is to use the name of the interface itself, another way is to specify
2404 the (local) address that is assigned to that interface (@var{local_address}). The
2405 former way is unambiguous and therefore preferable, but not all platforms
2408 Adding routes to IPv4 subnets:
2410 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2412 @tab @code{route add -net} @var{network_address} @code{netmask} @var{netmask} @var{interface}
2413 @item Linux iproute2
2414 @tab @code{ip route add} @var{network_address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2416 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2418 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2420 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2422 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address} @code{-interface}
2423 @item Darwin (MacOS/X)
2424 @tab @code{route add} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2426 @tab @code{netsh routing ip add persistentroute} @var{network_address} @var{netmask} @var{interface} @var{local_address}
2429 Adding routes to IPv6 subnets:
2431 @multitable {Darwin (MacOS/X)} {ifconfig route add -bla network address netmask netmask prefixlength interface}
2433 @tab @code{route add -A inet6} @var{network_address}@code{/}@var{prefixlength} @var{interface}
2434 @item Linux iproute2
2435 @tab @code{ip route add} @var{network_address}@code{/}@var{prefixlength} @code{dev} @var{interface}
2437 @tab @code{route add -inet6} @var{network_address}@code{/}@var{prefixlength} @var{local_address}
2439 @tab @code{route add -inet6} @var{network_address} @var{local_address} @code{-prefixlen} @var{prefixlength}
2441 @tab @code{route add -inet6} @var{network_address} @var{local_address} @code{-prefixlen} @var{prefixlength}
2443 @tab @code{route add -inet6} @var{network_address}@code{/}@var{prefixlength} @var{local_address} @code{-interface}
2444 @item Darwin (MacOS/X)
2447 @tab @code{netsh interface ipv6 add route} @var{network address}/@var{prefixlength} @var{interface}
2451 @c ==================================================================
2457 * Contact information::
2462 @c ==================================================================
2463 @node Contact information
2464 @section Contact information
2467 Tinc's website is at @url{http://www.tinc-vpn.org/},
2468 this server is located in the Netherlands.
2471 We have an IRC channel on the FreeNode and OFTC IRC networks. Connect to
2472 @uref{http://www.freenode.net/, irc.freenode.net}
2474 @uref{http://www.oftc.net/, irc.oftc.net}
2475 and join channel #tinc.
2478 @c ==================================================================
2483 @item Ivo Timmermans (zarq)
2484 @item Guus Sliepen (guus) (@email{guus@@tinc-vpn.org})
2487 We have received a lot of valuable input from users. With their help,
2488 tinc has become the flexible and robust tool that it is today. We have
2489 composed a list of contributions, in the file called @file{THANKS} in
2490 the source distribution.
2493 @c ==================================================================
2495 @unnumbered Concept Index
2497 @c ==================================================================
2501 @c ==================================================================