public File getRadiusCAFile() throws GuacamoleException {
        return environment.getProperty(
            RadiusGuacamoleProperties.RADIUS_CA_FILE,
            new File(environment.getGuacamoleHome(), "ca.crt")
        );
    }
Returns the CA file for validating certificates for encrypted
connections to the RADIUS server, as configured in
guacamole.properties.

@return
    The file name for the CA file for validating
    RADIUS server certificates

@throws GuacamoleException
    If guacamole.properties cannot be parsed.
extensions/guacamole-auth-radius/src/main/java/org/apache/guacamole/auth/radius/conf/ConfigurationService.java