Introduction

Since version 2.4, OpenVPN can be built using mbedtls as it's crypto backend, instead of OpenSSL. See ​https://tls.mbed.org/ for more information on mbedtls.

Limitations compared to OpenSSL

Note that the mbedtls variant of OpenVPN does not support the same feature set as the OpenSSL variant. The most prominent differences are listed in the latest ​README.mbedtls.

Building the mbedtls-enabled OpenVPN

OpenVPN 2.4 has full mbedtls support. Get the sources from ​the download page, or get the most recent (potentially unstable) code ​from github.

To build using mbedtls:

./configure --with-crypto-library=mbedtls
make
make install