bug#39542: Adding openvpn client configurations to guix system

[Damien Cassou]

Hi,

both OpenVPN and NetworkManager read network configurations from
/etc. This should make it possible to configure your favorite VPN client
configurations (and maybe wifi access points) in your /etc/config.scm.

An OpenVPN client connection typically consists of *.key files, *.pem
files and *.crt files. These should be placed under /etc/openvpn/client/.

Each OpenVPN client connection must be declared at the Network manager
level too. This means adding a *.nmconnection file in
/etc/NetworkManager/system-connections/.

It would be great if Guix could make that possible from my
/etc/config.scm file.

Thank you for your great work!

-- 
Damien Cassou

"Success is the ability to go from one failure to another without
losing enthusiasm." --Winston Churchill