OpenIKED is a free, permissively licensed Internet Key Exchange
(IKEv2) implementation, developed as part of the OpenBSD project.
It is intended to be a lean, secure and interoperable daemon that
allows for easy setup and management of IPsec VPNs.

The portable versions take the OpenBSD based source code and add
compatibility functions and build infrastructure for other operating
systems.

WWW: https://github.com/openiked/openiked-portable