Installation instructions for OpenVPN, a Secure Tunneling Daemon
Copyright (C) 2002-2008 OpenVPN Solutions LLC. This program is free software;
you can redistribute it and/or modify
it under the terms of the GNU General Public License version 2
as published by the Free Software Foundation.
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QUICK START:
Unix:
./configure && make && make-install
Windows:
./domake-win (see comments in the script for more info)
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To download OpenVPN, go to:
http://openvpn.net/download.html
For step-by-step installation instructions with real-world
examples see:
http://openvpn.net/howto.html
For examples see:
http://openvpn.net/examples.html
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SUPPORTED PLATFORMS:
(1) Linux 2.2+
(2) Solaris
(3) OpenBSD 3.0+ (Comes with OpenSSL and TUN devices by default)
(4) Mac OS X Darwin
(5) FreeBSD
(6) NetBSD
(7) Windows (Win 2K and higher)
SUPPORTED PROCESSOR ARCHITECTURES:
In general, OpenVPN is word size and endian independent, so
most processors should be supported. Architectures known to
work include Intel x86, Alpha, Sparc, Amd64, and ARM.
REQUIRES:
(1) TUN and/or TAP driver to allow user-space programs to control
a virtual point-to-point IP or Ethernet device. See
TUN/TAP Driver Configuration section below for more info.
OPTIONAL (but recommended):
(1) OpenSSL library, necessary for encryption, version 0.9.5 or higher
required, available from http://www.openssl.org/
(2) LZO real-time compression library, required for link compression,
available from http://www.oberhumer.com/opensource/lzo/
OpenBSD users can use ports or packages to install lzo, but remember
to add "--with-lzo-headers" and "--with-lzo-lib" directives to
"configure", pointing to /usr/local/include and /usr/local/lib
respectively since gcc will not find them otherwise.
(3) Pthread library.
OPTIONAL (for developers only):
(1) Autoconf 2.50 or higher + Automake 1.5 or higher
-- available from http://www.gnu.org/software/software.html
(2) Dmalloc library
-- available from http://dmalloc.com/
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CHECK OUT SOURCE FROM SUBVERSION REPOSITORY:
Check out stable version:
svn checkout http://svn.openvpn.net/projects/openvpn/trunk/openvpn openvpn
Check out beta21 branch:
svn checkout http://svn.openvpn.net/projects/openvpn/branches/BETA21/openvpn openvpn
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BUILD COMMANDS FROM TARBALL:
./configure
make
make install
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BUILD COMMANDS FROM SUBVERSION REPOSITORY CHECKOUT:
autoreconf -i -v
./configure
make
make install
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BUILD A TARBALL FROM SUBVERSION REPOSITORY CHECKOUT:
autoreconf -i -v
./configure
make dist
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LOOPBACK TESTS (after BUILD):
make check (Run all tests below)
Test Crypto:
./openvpn --genkey --secret key
./openvpn --test-crypto --secret key
Test SSL/TLS negotiations (runs for 2 minutes):
./openvpn --config sample-config-files/loopback-client (In one window)
./openvpn --config sample-config-files/loopback-server (Simultaneously in another window)
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OPTIONS for ./configure:
--enable-pthread Compile pthread support for
improved latency during SSL/TLS key
negotiations (Linux or Solaris only)
--disable-lzo Do not compile LZO compression support
--disable-crypto Do not compile OpenSSL crypto support
--disable-ssl Do not compile OpenSSL SSL support for
TLS-based key exchange
--with-ssl-headers=DIR Crypto/SSL Include files location
--with-ssl-lib=DIR Crypto/SSL Library location
--with-lzo-headers=DIR LZO Include files location
--with-lzo-lib=DIR LZO Library location
--with-ifconfig-path=PATH Path to ifconfig tool (only need to
specify if in a non-standard location)
--with-leak-check=TYPE Build with memory leak checking
TYPE = dmalloc or ssl
--enable-strict Enable strict compiler warnings
--enable-strict-options Enable strict options check between peers
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BUILDING ON LINUX 2.4+ FROM RPM
You can build a binary RPM directly from the OpenVPN tarball file:
rpmbuild -tb [tarball]
This command will build a binary RPM file and place it in the system
RPM directory. You can then install the RPM with the standard RPM
install command:
rpm -ivh [binary-rpm]
When you install the binary RPM, it will install
sample-scripts/openvpn.init, which can be used to
automatically start or stop one or more OpenVPN tunnels on system
startup or shutdown, based on OpenVPN .conf files in /etc/openvpn.
See the comments in openvpn.init for more information.
Installing the RPM will also configure the TUN/TAP device node
for linux 2.4.
Note that the current openvpn.spec file, which instructs the rpm tool
how to build a package, will build OpenVPN with all options enabled,
including OpenSSL, LZO, and pthread linkage. Therefore all of
these packages will need to be present prior to the RPM build, unless
you edit the openvpn.spec file.
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TUN/TAP Driver Configuration:
* Linux 2.4 or higher (with integrated TUN/TAP driver):
(1) make device node: mknod /dev/net/tun c 10 200
(2a) add to /etc/modules.conf: alias char-major-10-200 tun
(2b) load driver: modprobe tun
(3) enable routing: echo 1 > /proc/sys/net/ipv4/ip_forward
Note that either of steps (2a) or (2b) is sufficient. While (2a)
only needs to be done once per install, (2b) needs to be done once
per reboot. If you install from RPM (see above) and use the
openvpn.init script, these steps are taken care of for you.
* Linux 2.2 or Solaris:
You should obtain
version 1.1 of the TUN/TAP driver from
http://vtun.sourceforge.net/tun/
and follow the installation instructions.
If you use OpenVPN on Linux 2.2 or 2.4 or Solaris, you may be
suffering from a bug which causes connections to hang under heavy load.
The symptoms are very similar to the MTU problems discussed frequently
in the OpenVPN mailing lists. But it turns out that this bug is not caused by
MTU problems. It's a bug in the tun/tap driver. A patch is provided here:
http://openvpn.net/patch/tun-sb.patch
* Solaris
For 64 bit, I used the tun-1.1.tar.gz source and compiled it.
Of course there is a but :)
In the tun-1-1\solaris\Makefile I changed a line so it compiles with 64 bit
CFLAGS = $(DEFS) -m64 -O2 -Wall -D_KERNEL -I.
I just added -m64 and it worked.
The tun driver works fine as said previously, however we noticed there is a
minor problem when creating multiple tunnels on Solaris.
Mr Tycho Fruru changed the code in tun.c file where he locked the tun device
number to -1. This way it is impossible to specify the name of the tun device
but it is still possible to have multiple devices.
The modification will increment automatically meaning starting from tun0 --->
tunX I know you are not responsible for the tun coding but if you think the
modification can be useful for you feel free to use it.
http://openvpn.net/solaris/tun.c
* FreeBSD 4.1.1+:
FreeBSD ships with the TUN/TAP driver, and the device nodes for tap0,
tap1, tap2, tap3, tun0, tun1, tun2 and tun3 are made by default.
However, only the TUN driver is linked into the GENERIC kernel.
To load the TAP driver, enter:
kldload if_tap
See man rc(8) to find out how you can do this at boot time.
The easiest way is to install OpenVPN from the FreeBSD ports system,
the port includes a sample script to automatically load the TAP driver
at boot-up time.
* OpenBSD:
OpenBSD ships with tun0 and tun1 installed by default on pre-3.5 systems,
while 3.5 and later have dynamically created tun* devices so you only need
to create an empty /etc/hostname.tun0 (tun1, tun2 and so on) for each tun
you plan to use to create the device(s) at boot.
* Mac OS X:
2005.02.13: Angelo Laub has developed a GUI for OS X:
http://rechenknecht.net/OpenVPN-GUI/
2004.10.26: Mattias Nissler has developed a new TUN/TAP driver for
MAC OS X:
http://www-user.rhrk.uni-kl.de/~nissler/tuntap/
Christoph Pfisterer's old TUN driver can be obtained at
http://chrisp.de/en/projects/tunnel.html -- note that it
is no longer being maintained.
* Solaris9 Sparc/64
The kernel module for solaris
can be generated by adding the -m64 switch to a modern
gcc compiler (I'm using 3.2) The resulting kernel driver
needs to be manually copied to /kernel/drv/sparcv9/ and then a
reconfiguration reboot. (boot -r).
* Windows 2000/XP/2003/Vista
See domake-win for building instructions.
See INSTALL-win32.txt for usage info.
See the man page for more information, usage examples, and
information on firewall configuration.
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CAVEATS & BUGS:
* I have noticed cases where TCP sessions tunneled over the Linux
TAP driver (kernel 2.4.21 and 2.4.22) stall when lower --mssfix
values are used. The TCP sessions appear to unstall and resume
normally when the remote VPN endpoint is pinged.
* If run through a firewall using OpenBSDs packet filter PF and the
filter rules include a "scrub" directive, you may get problems talking
to Linux hosts over the tunnel, since the scrubbing will kill packets
sent from Linux hosts if they are fragmented. This is usually seen as
tunnels where small packets and pings get through but large packets
and "regular traffic" don't. To circumvent this, add "no-df" to
the scrub directive so that the packet filter will let fragments with
the "dont fragment"-flag set through anyway.
* Mixing OFB or CFB cipher modes with static key mode is not recommended,
and is flagged as an error on OpenVPN versions 1.2.1 and greater.
If you use the --cipher option to explicitly select an OFB or CFB
cipher AND you are using static key mode, it is possible that there
could be an IV collision if the OpenVPN daemons on both sides
of the connection are started at exactly the same time, since
OpenVPN uses a timestamp combined with a sequence number as the cipher
IV for OFB and CFB modes. This is not an issue if you are
using CBC cipher mode (the default), or if you are using OFB or CFB
cipher mode with SSL/TLS authentication.
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Subject: [Openvpn-users] Re: Windows XP 64 bit
From: Hypherion
Date: Thu, 14 Apr 2005 07:01:17 +0000 (UTC)
Well I managed to build a Windows XP 64 bit driver myself and it's working
great, I can connect to my server again :)
I had to use the WinDDK for Windows 2003 Service Pack 1 and just built the
driver in the Windows 2003 AMD64 environment. I had to comment out the
MAPINFO:FIXUPS directive in the SOURCES file.
Then I copied and renamed (devcon.exe/tapinstall.exe) from
C:\WINDDK\3790.1830\tools\devcon\amd64.
I had to edit the file OemWin2k.inf and change the Manufactured + Product
Section to:
[Manufacturer]
%Provider% = tap0901, NTamd64
[tap0901.NTamd64]
%DeviceDescription% = tap0901.ndi, tap0901
