Drupal 7 Shibboleth 2 Authentication Module

simple_shibb.module.php

<?php

function simple_shibb_init() {

	$shib_session = _simple_shibb_get_session_username(); 
	$drupal_session = user_is_logged_in();

	if($drupal_session && !$shib_session) {

		$force_logout = _simple_shibb_get_setting('logout_expired_sessions');
		if($force_logout) {

			_simple_shibb_do_logout();

		}
	}
	
	if($shib_session) {

		_simple_shibb_do_login(); 
	}


}


function simple_shibb_form_alter(&$form, &$form_state, $form_id) {

	$login_text = _simple_shibb_get_setting('login_text'); 
	$login_url = _simple_shibb_get_setting('login_url');

	if (!empty($text) && $form_id === 'user_login') {

		$form['simple_shibb'] = array(
			'#type' => 'markup',
			'#weight' => -20,
			'#markup' => l(t($login_text), $login_url)
		);

	}

}


function _simple_shibb_do_logout() {

	global $user; 
	
	$logout_url = _simple_shibb_get_setting('shibboleth_sp_logout_url'); 
	module_invoke_all('user_logout', $user);
	session_destroy();
	drupal_goto($logout_url);

}

function _simple_shibb_do_login() {
	
	global $user; 
	_simple_shibb_register_user(); 

	$user = user_load_by_mail(_simple_shibb_get_session_email()); 
	drupal_session_regenerate();

}


function _simple_shibb_register_user() {
	
	$session_username = _simple_shibb_get_session_username(); 
	$session_email = _simple_shibb_get_session_email(); 

	$drupal_user = user_load_by_mail($session_email);

	// Existing accounts for email 
	if($drupal_user->uid) {

		$drupal_user->mail = $session_email; 
		// Add or unset roles based on provider information 
		$drupal_user->roles = array_merge($drupal_user->roles, _simple_shibb_get_session_roles()); 
		user_save($drupal_user->uid, $drupal_user);

	}

	// New accounts 
	else {
		
		$fields = array(
			'name' => $session_username,
			'mail' => $session_email,
			'pass' => user_password(8),
			'status' => 1,
			'init' => 'email address',
			'roles' => array(DRUPAL_AUTHENTICATED_RID => 'authenticated user',), 
			),
		);
	
		$field['roles'] += _simple_shibb_get_session_roles(); 
	
		$new_user = user_save('', $fields);
		$new_user->password = $fields['pass'];
	
		drupal_mail('user', 'register_no_approval_required', $new_user->mail, NULL, array('account' => $new_user), variable_get('site_mail'));
	}

}


function _simple_shibb_get_session_username() {

	$field = _simple_shibb_get_setting('shibboleth_session_username_variable');
	return $_SERVER[$field];
	
}


function _simple_shibb_get_session_email() {

	$field = _simple_shibb_get_setting('shibboleth_session_email_variable');
	return $_SERVER[$field];
	
}


function _simple_shibb_get_session_roles() {

	$roles = array(
		'test_one' => true,
		);

	return $roles; 
	
}


function _simple_shibb_build_url($url) {

	$options = array( 
		'absolute' => true,
		'alias' => false,
		'https' => (_simple_shibb_get_setting('force_https_login') ? true : false),
	);

	return url($url, $options); 

}


function _simple_shibb_get_setting($field) {

	$settings = _simple_shibb_load_settings(); 
	
	if($field === 'shibbolet_sp_login_url') {
		return _simple_shibb_build_url($settings[$field]);
	}
	
	if($field === 'shibboleth_sp_logout_url') {
		return _simple_shibb_build_url($settings[$field]);
	}

	return $settings[$field]; 

}


function _simple_shibb_load_settings() {
	
	include('simple_shibb.settings.php'); 
	$hosts = $settings['hosts']; 

	if(!empty($hosts[$_SERVER['SERVER_NAME']]) {
		return $hosts[$_SERVER['SERVER_NAME']]; 
	}
	
	if(!empty($hosts[$_SERVER['SERVER_ADDR']]) {
		return $hosts[$_SERVER['SERVER_ADDR']];
	}
	
	if(!empty($hosts['*']) {
		return $hosts['*'];
	}

	return array(); 

}