This is the info manual for @value{PACKAGE} version @value{VERSION}, a Virtual Private Network daemon.
-Copyright @copyright{} 1998-2014 Ivo Timmermans,
+Copyright @copyright{} 1998-2016 Ivo Timmermans,
Guus Sliepen <guus@@tinc-vpn.org> and
Wessel Dankers <wsl@@tinc-vpn.org>.
@vskip 0pt plus 1filll
This is the info manual for @value{PACKAGE} version @value{VERSION}, a Virtual Private Network daemon.
-Copyright @copyright{} 1998-2014 Ivo Timmermans,
+Copyright @copyright{} 1998-2016 Ivo Timmermans,
Guus Sliepen <guus@@tinc-vpn.org> and
Wessel Dankers <wsl@@tinc-vpn.org>.
* Configuration::
* Running tinc::
* Controlling tinc::
+* Invitations::
* Technical information::
* Platform specific information::
* About us::
@cindex release
For an up to date list of supported platforms, please check the list on
our website:
-@uref{http://www.tinc-vpn.org/platforms/}.
+@uref{https://www.tinc-vpn.org/platforms/}.
@c
@c
@node Configuration of OpenBSD kernels
@subsection Configuration of OpenBSD kernels
-For OpenBSD version 2.9 and higher,
-the tun driver is included in the default kernel configuration.
-There is also a kernel patch from @uref{http://diehard.n-r-g.com/stuff/openbsd/}
-which adds a tap device to OpenBSD which should work with tinc,
-but with recent versions of OpenBSD,
-a tun device can act as a tap device by setting the link0 option with ifconfig.
+Recent versions of OpenBSD come with both tun and tap devices enabled in the default kernel configuration.
@c ==================================================================
For Solaris 8 (SunOS 5.8) and higher,
the tun driver may or may not be included in the default kernel configuration.
If it isn't, the source can be downloaded from @uref{http://vtun.sourceforge.net/tun/}.
-For x86 and sparc64 architectures, precompiled versions can be found at @uref{http://www.monkey.org/~dugsong/fragroute/}.
+For x86 and sparc64 architectures, precompiled versions can be found at @uref{https://www.monkey.org/~dugsong/fragroute/}.
If the @file{net/if_tun.h} header file is missing, install it from the source package.
@subsection Configuration of Darwin (MacOS/X) kernels
Tinc on Darwin relies on a tunnel driver for its data acquisition from the kernel.
-Tinc supports either the driver from @uref{http://tuntaposx.sourceforge.net/},
+OS X version 10.6.8 and later have a built-in tun driver called "utun".
+Tinc also supports the driver from @uref{http://tuntaposx.sourceforge.net/},
which supports both tun and tap style devices,
-and also the driver from from @uref{http://chrisp.de/en/projects/tunnel.html}.
-The former driver is recommended.
-The tunnel driver must be loaded before starting tinc with the following command:
-@example
-kmodload tunnel
-@end example
+By default, tinc expects the tuntaposx driver to be installed.
+To use the utun driver, set add @code{Device = utunX} to @file{tinc.conf},
+where X is the desired number for the utun interface.
+You can also omit the number, in which case the first free number will be chosen.
@c ==================================================================
@subsection Configuration of Windows
You will need to install the latest TAP-Win32 driver from OpenVPN.
-You can download it from @uref{http://openvpn.sourceforge.net}.
+You can download it from @uref{https://openvpn.net/index.php/open-source/downloads.html}.
Using the Network Connections control panel,
configure the TAP-Win32 network interface in the same way as you would do from the tinc-up script,
as explained in the rest of the documentation.
@cindex requirements
@cindex libraries
-Before you can configure or build tinc, you need to have the OpenSSL, zlib,
+Before you can configure or build tinc, you need to have the LibreSSL or OpenSSL, zlib,
lzo, curses and readline libraries installed on your system. If you try to
configure tinc without having them installed, configure will give you an error
message, and stop.
@menu
-* OpenSSL::
+* LibreSSL/OpenSSL::
* zlib::
* lzo::
* libcurses::
@c ==================================================================
-@node OpenSSL
-@subsection OpenSSL
+@node LibreSSL/OpenSSL
+@subsection LibreSSL/OpenSSL
+@cindex LibreSSL
@cindex OpenSSL
For all cryptography-related functions, tinc uses the functions provided
-by the OpenSSL library.
+by the LibreSSL or the OpenSSL library.
If this library is not installed, you wil get an error when configuring
tinc for build. Support for running tinc with other cryptographic libraries
available. Make sure you install the development AND runtime versions
of this package.
-If you have to install OpenSSL manually, you can get the source code
-from @url{http://www.openssl.org/}. Instructions on how to configure,
-build and install this package are included within the package. Please
-make sure you build development and runtime libraries (which is the
+If your operating system comes neither with LibreSSL or OpenSSL, you have to
+install one manually. It is recommended that you get the latest version of
+LibreSSL from @url{http://www.libressl.org/}. Instructions on how to
+configure, build and install this package are included within the package.
+Please make sure you build development and runtime libraries (which is the
default).
-If you installed the OpenSSL libraries from source, it may be necessary
+If you installed the LibreSSL or OpenSSL libraries from source, it may be necessary
to let configure know where they are, by passing configure one of the
---with-openssl-* parameters.
+--with-openssl-* parameters. Note that you even have to use --with-openssl-* if you
+are using LibreSSL.
@example
---with-openssl=DIR OpenSSL library and headers prefix
---with-openssl-include=DIR OpenSSL headers directory
+--with-openssl=DIR LibreSSL/OpenSSL library and headers prefix
+--with-openssl-include=DIR LibreSSL/OpenSSL headers directory
(Default is OPENSSL_DIR/include)
---with-openssl-lib=DIR OpenSSL library directory
+--with-openssl-lib=DIR LibreSSL/OpenSSL library directory
(Default is OPENSSL_DIR/lib)
@end example
The complete source code of tinc is covered by the GNU GPL version 2.
Since the license under which OpenSSL is distributed is not directly
compatible with the terms of the GNU GPL
-@uref{http://www.openssl.org/support/faq.html#LEGAL2}, we
+@uref{https://www.openssl.org/support/faq.html#LEGAL2}, we
include an exemption to the GPL (see also the file COPYING.README) to allow
everyone to create a statically or dynamically linked executable:
@quotation
Hereby I grant a special exception to the tinc VPN project
-(http://www.tinc-vpn.org/) to link the LZO library with the OpenSSL library
-(http://www.openssl.org).
+(https://www.tinc-vpn.org/) to link the LZO library with the OpenSSL library
+(https://www.openssl.org).
Markus F.X.J. Oberhumer
@end quotation
of this package.
If you have to install zlib manually, you can get the source code
-from @url{http://www.gzip.org/zlib/}. Instructions on how to configure,
+from @url{http://www.zlib.net/}. Instructions on how to configure,
build and install this package are included within the package. Please
make sure you build development and runtime libraries (which is the
default).
of this package.
If you have to install lzo manually, you can get the source code
-from @url{http://www.oberhumer.com/opensource/lzo/}. Instructions on how to configure,
+from @url{https://www.oberhumer.com/opensource/lzo/}. Instructions on how to configure,
build and install this package are included within the package. Please
make sure you build development and runtime libraries (which is the
default).
If you cannot use one of the precompiled packages, or you want to compile tinc
for yourself, you can use the source. The source is distributed under
the GNU General Public License (GPL). Download the source from the
-@uref{http://www.tinc-vpn.org/download/, download page}, which has
-the checksums of these files listed; you may wish to check these with
-md5sum before continuing.
+@uref{https://www.tinc-vpn.org/download/, download page}.
Tinc comes in a convenient autoconf/automake package, which you can just
treat the same as any other package. Which is just untar it, type
@node Darwin (MacOS/X) build environment
@subsection Darwin (MacOS/X) build environment
-In order to build tinc on Darwin, you need to install the MacOS/X Developer Tools
-from @uref{http://developer.apple.com/tools/macosxtools.html} and
-a recent version of Fink from @uref{http://www.finkproject.org/}.
+In order to build tinc on Darwin, you need to install Xcode from @uref{https://developer.apple.com/xcode/}.
+It might also help to install a recent version of Fink from @uref{http://www.finkproject.org/}.
-After installation use fink to download and install the following packages:
-autoconf25, automake, dlcompat, m4, openssl, zlib and lzo.
+You need to download and install LibreSSL (or OpenSSL) and LZO,
+either directly from their websites (see @ref{Libraries}) or using Fink.
@c ==================================================================
@node Cygwin (Windows) build environment
@subsection Cygwin (Windows) build environment
If Cygwin hasn't already been installed, install it directly from
-@uref{http://www.cygwin.com/}.
+@uref{https://www.cygwin.com/}.
When tinc is compiled in a Cygwin environment, it can only be run in this environment,
but all programs, including those started outside the Cygwin environment, will be able to use the VPN.
@subsection MinGW (Windows) build environment
You will need to install the MinGW environment from @uref{http://www.mingw.org}.
+You also need to download and install LibreSSL (or OpenSSL) and LZO.
When tinc is compiled using MinGW it runs natively under Windows,
it is not necessary to keep MinGW installed.
and on Linux, unless specified otherwise, the name of the virtual network interface will be the same as the network name.
However, it is not strictly necessary that you call tinc with the -n
-option. If you don not use it, the network name will just be empty, and
+option. If you do not use it, the network name will just be empty, and
tinc will look for files in @file{@value{sysconfdir}/tinc/} instead of
@file{@value{sysconfdir}/tinc/@var{netname}/};
the configuration file will then be @file{@value{sysconfdir}/tinc/tinc.conf},
Do NOT connect multiple tinc daemons to the same multicast address, this will very likely cause routing loops.
Also note that this can cause decrypted VPN packets to be sent out on a real network if misconfigured.
+@cindex fd
+@item fd
+Use a file descriptor.
+All packets are read from this interface.
+Packets received for the local node are written to it.
+
@cindex UML
@item uml (not compiled in by default)
Create a UNIX socket with the filename specified by
followed by an IP header.
This mode should support both IPv4 and IPv6 packets.
+@cindex utun
+@item utun (OS X)
+Set type to utun.
+This is only supported on OS X version 10.6.8 and higher, but doesn't require the tuntaposx module.
+This mode should support both IPv4 and IPv6 packets.
+
@item tap (BSD and Linux)
Set type to tap.
Tinc will expect packets read from the virtual network device
Currently, local discovery is implemented by sending some packets to the local address of the node during UDP discovery.
This will not work with old nodes that don't transmit their local address.
-@cindex LocalDiscoveryAddress
-@item LocalDiscoveryAddress <@var{address}>
-If this variable is specified, local discovery packets are sent to the given @var{address}.
-
@cindex Mode
@item Mode = <router|switch|hub> (router)
This option selects the way packets are routed to other daemons.
@cindex Name
@item Name = <@var{name}> [required]
This is a symbolic name for this connection.
-The name should consist only of alfanumeric and underscore characters (a-z, A-Z, 0-9 and _), and is case sensitive.
+The name must consist only of alfanumeric and underscore characters (a-z, A-Z, 0-9 and _), and is case sensitive.
If Name starts with a $, then the contents of the environment variable that follows will be used.
In that case, invalid characters will be converted to underscores.
@end table
@cindex ReplayWindow
-@item ReplayWindow = <bytes> (16)
+@item ReplayWindow = <bytes> (32)
This is the size of the replay tracking window for each remote node, in bytes.
The window is a bitfield which tracks 1 packet per bit, so for example
-the default setting of 16 will track up to 128 packets in the window. In high
+the default setting of 32 will track up to 256 packets in the window. In high
bandwidth scenarios, setting this to a higher value can reduce packet loss from
the interaction of replay tracking with underlying real packet loss and/or
reordering. Setting this to zero will disable replay tracking completely and
The minimum amount of time between sending periodic updates about UDP addresses, which are mostly useful for UDP hole punching.
@cindex UDPRcvBuf
-@item UDPRcvBuf = <bytes> (OS default)
+@item UDPRcvBuf = <bytes> (1048576)
Sets the socket receive buffer size for the UDP socket, in bytes.
-If unset, the default buffer size will be used by the operating system.
+If set to zero, the default buffer size will be used by the operating system.
+Note: this setting can have a significant impact on performance, especially raw throughput.
@cindex UDPSndBuf
-@item UDPSndBuf = <bytes> Pq OS default
+@item UDPSndBuf = <bytes> (1048576)
Sets the socket send buffer size for the UDP socket, in bytes.
-If unset, the default buffer size will be used by the operating system.
+If set to zero, the default buffer size will be used by the operating system.
+Note: this setting can have a significant impact on performance, especially raw throughput.
+
+@cindex UPnP
+@item UPnP = <yes|udponly|no> (no)
+If this option is enabled then tinc will search for UPnP-IGD devices on the local network.
+It will then create and maintain port mappings for tinc's listening TCP and UDP ports.
+If set to "udponly", tinc will only create a mapping for its UDP (data) port, not for its TCP (metaconnection) port.
+Note that tinc must have been built with miniupnpc support for this feature to be available.
+Furthermore, be advised that enabling this can have security implications, because the miniupnpc library that
+tinc uses might not be well-hardened with regard to malicious UPnP replies.
+
+@cindex UPnPDiscoverWait
+@item UPnPDiscoverWait = <seconds> (5)
+The amount of time to wait for replies when probing the local network for UPnP devices.
+
+@cindex UPnPRefreshPeriod
+@item UPnPRefreshPeriod = <seconds> (5)
+How often tinc will re-add the port mapping, in case it gets reset on the UPnP device.
+This also controls the duration of the port mapping itself, which will be set to twice that duration.
@end table
@cindex Cipher
@item Cipher = <@var{cipher}> (blowfish)
The symmetric cipher algorithm used to encrypt UDP packets using the legacy protocol.
-Any cipher supported by OpenSSL is recognized.
+Any cipher supported by LibreSSL or OpenSSL is recognized.
Furthermore, specifying "none" will turn off packet encryption.
It is best to use only those ciphers which support CBC mode.
This option has no effect for connections using the SPTPS protocol, which always use AES-256-CTR.
@cindex Digest
@item Digest = <@var{digest}> (sha1)
The digest algorithm used to authenticate UDP packets using the legacy protocol.
-Any digest supported by OpenSSL is recognized.
+Any digest supported by LibreSSL or OpenSSL is recognized.
Furthermore, specifying "none" will turn off packet authentication.
This option has no effect for connections using the SPTPS protocol, which always use HMAC-SHA-256.
When this option is enabled, tinc will try to discover the path MTU to this node.
After the path MTU has been discovered, it will be enforced on the VPN.
+@cindex MTUInfoInterval
+@item MTUInfoInterval = <seconds> (5)
+The minimum amount of time between sending periodic updates about relay path MTU. Useful for quickly determining MTU to indirect nodes.
+
@cindex Port
@item Port = <@var{port}> (655)
This is the port this tinc daemon listens on.
Prefixlength is the number of bits set to 1 in the netmask part; for
example: netmask 255.255.255.0 would become /24, 255.255.252.0 becomes
/22. This conforms to standard CIDR notation as described in
-@uref{http://www.ietf.org/rfc/rfc1519.txt, RFC1519}
+@uref{https://www.ietf.org/rfc/rfc1519.txt, RFC1519}
A Subnet can be given a weight to indicate its priority over identical Subnets
owned by different nodes. The default weight is 10. Lower values indicate
@cindex scripts
Apart from reading the server and host configuration files,
tinc can also run scripts at certain moments.
+Below is a list of filenames of scripts and a description of when they are run.
+A script is only run if it exists and if it is executable.
+
+Scripts are run synchronously;
+this means that tinc will temporarily stop processing packets until the called script finishes executing.
+This guarantees that scripts will execute in the exact same order as the events that trigger them.
+If you need to run commands asynchronously, you have to ensure yourself that they are being run in the background.
+
Under Windows (not Cygwin), the scripts should have the extension @file{.bat} or @file{.cmd}.
@table @file
started and has connected to the virtual network device.
It should be used to set up the corresponding network interface,
but can also be used to start other things.
+
Under Windows you can use the Network Connections control panel instead of creating this script.
@cindex tinc-down
red nodes are unreachable, orange nodes are indirectly reachable, green nodes are directly reachable.
Black nodes are either directly or indirectly reachable, but direct reachability has not been tried yet.
+@item dump invitations
+Dump a list of outstanding invitations.
+The filename of the invitation, as well as the name of the node that is being invited is shown for each invitation.
+
@cindex info
@item info @var{node} | @var{subnet} | @var{address}
Show information about a particular @var{node}, @var{subnet} or @var{address}.
Most problems must be corrected by the user itself, however in some cases (like file permissions and missing public keys),
tinc will ask if it should fix the problem.
+@cindex sign
+@item sign [@var{filename}]
+Sign a file with the local node's private key.
+If no @var{filename} is given, the file is read from standard input.
+The signed file is written to standard output.
+
+@cindex verify
+@item verify @var{name} [@var{filename}]
+
+Check the signature of a file against a node's public key.
+The @var{name} of the node must be given,
+or can be "." to check against the local node's public key,
+or "*" to allow a signature from any node whose public key is known.
+If no @var{filename} is given, the file is read from standard input.
+If the verification is succesful, a copy of the input with the signature removed is written to standard output, and the exit code will be zero.
+If the verification failed, nothing will be written to standard output, and the exit code will be non-zero.
+
@end table
@c ==================================================================
@end table
+@c ==================================================================
+@node Invitations
+@chapter Invitations
+
+Invitations are an easy way to add new nodes to an existing VPN. Invitations
+can be created on an existing node using the @code{tinc invite} command, which
+generates a relatively short URL which can be given to someone else, who uses
+the @code{tinc join} command to automatically set up tinc so it can connect to
+the inviting node. The next sections describe how invitations actually work,
+and how to further automate the invitations.
+
+@menu
+* How invitations work::
+* Invitation file format::
+* Writing an invitation-created script::
+@end menu
+
+
+@c ==================================================================
+@node How invitations work
+@section How invitations work
+
+When an invitation is created on a node (which from now on we will call the
+server) using the @code{tinc invite} command, an invitation file is created
+that contains all the information necessary for the invitee (which we will call
+the client) to create its configuration files. The invitation file is stays on
+the server, but a URL is generated that has enough information for the client
+to contact the server and to retrieve the invitation file. The whole URL is
+around 80 characters long and looks like this:
+
+@example
+server.example.org:12345/cW1NhLHS-1WPFlcFio8ztYHvewTTKYZp8BjEKg3vbMtDz7w4
+@end example
+
+It is composed of four parts:
+
+@example
+hostname : port / keyhash cookie
+@end example
+
+The hostname and port tell the client how to reach the tinc daemon on the server.
+The part after the slash looks like one blob, but is composed of two parts.
+The keyhash is the hash of the public key of the server.
+The cookie is a shared secret that identifies the client to the server.
+
+When the client connects to the server in order to join the VPN, the client and
+server will exchange temporary public keys. The client verifies that the hash
+of the server's public key matches the keyhash from the invitation URL. If
+not, it will immediately exit with an error. Otherwise, an ECDH exchange will
+happen so the client and server can communicate privately with each other. The
+client will then present the cookie to the server. The server uses this to
+look up the corresponding invitation file it generated earlier. If it exists,
+it will send the invitation file to the client. The client will also create a
+permanent public key, and send it to the server. After the exchange is
+completed, the connection is broken. The server creates a host config file for
+the client containing the client's permanent public key, and the client creates
+tinc.conf, host config files and possibly a tinc-up script based on the
+information in the invitation file.
+
+It is important that the invitation URL is kept secret until it is used; if
+another person gets a copy of the invitation URL before the real client runs
+the @code{tinc join} command, then that other person can try to join the VPN.
+
+
+@c ==================================================================
+@node Invitation file format
+@section Invitation file format
+
+The contents of an invitation file that is generated by the @code{tinc invite}
+command looks like this:
+
+@example
+Name = client
+Netname = vpn
+ConnectTo = server
+#-------------------------------------#
+Name = server
+Ed25519PublicKey = augbnwegoij123587...
+Address = server.example.com
+@end example
+
+The file is basically a concatenation of several host config blocks. Each host
+config block starts with @code{Name = ...}. Lines that look like @code{#---#}
+are not important, it just makes it easier for humans to read the file.
+
+The first host config block is always the one representing the invitee. So the
+first Name statement determines the name that the invitee will get. From the
+first block, the @file{tinc.conf} and @file{hosts/client} files will be
+generated; the @code{tinc join} command on the client will automatically
+separate statements based on whether they should be in @file{tinc.conf} or in a
+host config file. Some statements are special and are treated differently:
+
+@table @asis
+@item Netname = <@var{netname}>
+This is a hint to the invitee which netname to use for the VPN. It is used if
+the invitee did not already specify a netname, and if there is no pre-existing
+configuration with the same netname.
+
+@cindex Ifconfig
+@item Ifconfig = <@var{address}[/@var{netmask}] | dhcp | dhcp6 | slaac>
+This is a hint for generating a @file{tinc-up} script.
+If an address is specified, a command will be added to @file{tinc-up} so the VPN interface will be configured to have the given address.
+If it is the word "dhcp", a command will be added to start a DHCP client on the VPN interface.
+If it is the word dhcpv6, it will be a DHCPv6 client.
+If it is "slaac", then it will add commands to enable IPv6 stateless address autoconfiguration.
+It is also possible to specify a MAC address, in which case a command will be added to set the MAC address of the VPN interface.
+
+The exact commands added to the @file{tinc-up} script depends on the operating system the client is using.
+Multiple Ifconfig statements can be specified, however one should only use one Ifconfig statement per address family.
+
+@cindex Route
+@item Route = <@var{address}[/@var{netmask}]> [<@var{gateway}>]
+This is a hint for generating a @file{tinc-up} script.
+Route statements are similar to Ifconfig statements, but add routes instead of addresses.
+These only allow IPv4 and IPv6 routes.
+If no gateway address is specified, the route is directed to the VPN interface.
+In general, a gateway is only necessary when running tinc in switch mode.
+@end table
+
+Subsequent host config blocks are copied verbatim into their respective files
+in @file{hosts/}. The invitation file generated by @code{tinc invite} will
+normally only contain two blocks; one for the client and one for the server.
+
+
+@c ==================================================================
+@node Writing an invitation-created script
+@section Writing an invitation-created script
+
+When an invitation is generated, the "invitation-created" script is called (if
+it exists) right after the invitation file is written, but before the URL has
+been written to stdout. This allows one to change the invitation file
+automatically before the invitation URL is passed to the invitee. Here is an
+example shell script that aproximately recreates the default invitation file:
+
+@example
+#!/bin/sh
+
+cat >$INVITATION_FILE <<EOF
+Name = $NODE
+Netname = $NETNAME
+ConnectTo = $NAME
+#----------------#
+EOF
+
+tinc export >>$INVITATION_FILE
+@end example
+
+You can add more ConnectTo statements, and change `tinc export` to `tinc
+export-all` for example. But you can also use the script to automatically hand
+out a Subnet to the invitee. Note that the script doesn't have to be a shell script,
+you can use any language, it just has to be executable.
+
+
@c ==================================================================
@node Technical information
@chapter Technical information
packets they can intercept. The encryption algorithm and message authentication
algorithm can be changed in the configuration. The length of the message
authentication codes is also adjustable. The length of the key for the
-encryption algorithm is always the default length used by OpenSSL.
+encryption algorithm is always the default length used by LibreSSL/OpenSSL.
The SPTPS protocol is described in @ref{Simple Peer-to-Peer Security}.
For comparison, this is how SPTPS UDP packets look:
In August 2000, we discovered the existence of a security hole in all versions
of tinc up to and including 1.0pre2. This had to do with the way we exchanged
keys. Since then, we have been working on a new authentication scheme to make
-tinc as secure as possible. The current version uses the OpenSSL library and
+tinc as secure as possible. The current version uses the LibreSSL or OpenSSL library and
uses strong authentication with RSA keys.
On the 29th of December 2001, Jerome Etienne posted a security analysis of tinc
@section Contact information
@cindex website
-Tinc's website is at @url{http://www.tinc-vpn.org/},
+Tinc's website is at @url{https://www.tinc-vpn.org/},
this server is located in the Netherlands.
@cindex IRC
We have an IRC channel on the FreeNode and OFTC IRC networks. Connect to
-@uref{http://www.freenode.net/, irc.freenode.net}
+@uref{https://freenode.net/, irc.freenode.net}
or
-@uref{http://www.oftc.net/, irc.oftc.net}
+@uref{https://www.oftc.net/, irc.oftc.net}
and join channel #tinc.
projects / tinc / blobdiff