OpenVPN 3

OpenVPN 3 is a C++ class library that implements the functionality of an OpenVPN client, and is protocol-compatible with the OpenVPN 2.x branch.

OpenVPN 3 includes a minimal client wrapper (cli) that links in with the library and provides basic command line functionality.

NOTE: As of 2014, OpenVPN 3 is primarily of interest to developers because it does not yet replicate the full functionality of OpenVPN 2.

Building OpenVPN 3 client on Mac OS X

OpenVPN 3 should be built in a non-root Mac OS X account. Make sure that Xcode is installed with optional command-line tools. (These instructions have been tested with Xcode 5.1.1).

Create the directories ~/src and ~/src/mac:

mkdir -p ~/src/mac

Clone the OpenVPN 3 repo:

cd ~/src
mkdir ovpn3
cd ovpn3
git clone ... core

Export the shell variable O3 to point to the OpenVPN 3 top level directory:

export O3=~/src/ovpn3

Download source tarballs (.tar.gz or .tgz) for these dependency libraries into ~/Downloads

See the file $O3/core/deps/lib-versions for the expected version numbers of each dependency. If you want to use a different version of the library than listed here, you can edit this file.

1. Boost -- http://www.boost.org/
2. PolarSSL (1.3.4 or higher) -- https://polarssl.org/
3. Snappy -- https://code.google.com/p/snappy/
4. LZ4 -- https://code.google.com/p/lz4/

Note that while LZO and OpenSSL are listed in lib-versions, they are not required for Mac builds.

Build the dependencies:

OSX_ONLY=1 $O3/core/scripts/mac/build-all

Now build the OpenVPN 3 client executable:

cd $O3/core
. vars/vars-osx
. vars/setpath
cd test/ovpncli
STRIP=1 PSSL=1 SNAP=1 LZ4=1 build cli

This will build the OpenVPN 3 client library with a small client wrapper (cli). It will also statically link in all external dependencies (Boost, PolarSSL, LZ4, and Snappy), so cli may be distributed to other Macs and will run as a standalone executable.

These build scripts will create a "fat" Mac OS X executable with support for both x86_x64 and i386 architectures, with a minimum deployment target of 10.6.x. The Mac OS X tuntap driver is not required, as OpenVPN 3 can use the integrated utun interface if available.

To view the client wrapper options:

./cli -h

To connect:

./cli client.ovpn