To install Cockpit:
$ dnf install cockpit
To enable Cockpit:
$ systemctl enable --now cockpit.socket
SSL certificate should be stored in /etc/cockpit/ws-certs.d with a .cert extension. The file should contain the certificate and its private key.
To check which certificate cockpit-ws will use:
$ remotectl certificate
See Cockpit Certificates.
SSL ciphers are defined in /etc/systemd/system/cockpit.service.d/ssl.conf, for example:
When running as a container cockpit will establish SSH to the underlying host.
Cockpit can use TLS client certificates for authenticating users. This requires the host to be in an Identity Management domain like FreeIPA or Active Directory, which can associate certificates to users.
Cockpit has API available for writing packages. There is no API available for external callers to invoke via HTTP, REST or otherwise.