icingaweb2/doc/external_authentication.md

Externel Authentication

It is possible to use the authentication mechanism of the webserver, instead of using the internal authentication-manager to authenticate users. This might be useful if you only have very few users, and user management over .htaccess is sufficient, or if you must use some other authentication mechanism that is only available through your webserver.

When external authentication is used, Icingaweb will entrust the complete authentication process to the external authentication provider (the webserver): The provider should take care of authenticating the user and declining all requests with invalid or missing credentials. When the authentication was succesful, it should provide the authenticated users name to its php-module and Icingaweb will assume that the user is authorized to access the page. Because of this it is very important that the webservers authentication is configured correctly, as wrong configuration could lead to unauthorized access to the site, or a broken login-process.

Use External Authentication

Using external authentication in Icingaweb requires two steps to work:

1. The external authentication must be set up correctly to always authenticate the users.
2. Icingaweb must be configured to use the external authentication.

Prepare the External Authentication Provider

This step depends heavily on the used webserver and authentication mechanism you want to use. It is not possible to cover all possibillities and you should probably read the documentation for your webserver for detailed instructions on how to set up authentication properly.

In general, you need to make sure that:

- All routes require authentication
- Only permitted users are allowed to authenticate

Example Configuration for Apache and HTTPDigestAuthentication

The following example will show how to enable external authentication in Apache using HTTP Digest Authentication.

Create users

To create users for a digest authentication we can use the tool htdigest. We choose .icingawebdigest as a name for the created file, containing the user credentials.

This command will create a new file with the user jdoe. htdigest will prompt you for your password, after it has been executed. If you want to add more users to the file you need to ommit the -c parameter in all further commands to avoInid the file to be overwritten.

	sudo htdigest -c /etc/httpd/conf.d/.icingawebdigest "Icingaweb 2" jdoe

Set up authentication

The webserver should require authentication for all public icingaweb files.

	<Directory "/var/www/html/icingaweb">
		AuthType digest
		AuthName "Icingaweb 2"
		AuthDigestProvider file
		AuthUserFile /etc/httpd/conf.d/.icingawebdigest
		Require valid-user
	</Directory>		

Prepare Icingaweb

When the external authentication is set up correctly, we need to configure IcingaWeb to use it as an authentication source. The configuration key authenticationMode in the section global defines if the authentication should be handled internally or externally. Since we want to delegate the authentication to the Webserver we choose "external" as the new value:

	[global]
	; ...
	authenticationMode = "external"
	; ...