The [MACsec] section only applies for network devices of kind
"macsec", and accepts the following keys:
Port=
Specifies the port to be used for the MACsec transmit
channel. The port is used to make secure channel identifier
(SCI). Takes a value between 1 and 65535. Defaults to unset.
Encrypt=
Takes a boolean. When true, enable encryption. Defaults to
unset.