cacti/include/auth.php

<?php
/*
 +-------------------------------------------------------------------------+
 | Copyright (C) 2004-2026 The Cacti Group                                 |
 |                                                                         |
 | This program is free software; you can redistribute it and/or           |
 | modify it under the terms of the GNU General Public License             |
 | as published by the Free Software Foundation; either version 2          |
 | of the License, or (at your option) any later version.                  |
 |                                                                         |
 | This program is distributed in the hope that it will be useful,         |
 | but WITHOUT ANY WARRANTY; without even the implied warranty of          |
 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           |
 | GNU General Public License for more details.                            |
 +-------------------------------------------------------------------------+
 | Cacti: The Complete RRDtool-based Graphing Solution                     |
 +-------------------------------------------------------------------------+
 | This code is designed, written, and maintained by the Cacti Group. See  |
 | about.php and/or the AUTHORS file for specific developer information.   |
 +-------------------------------------------------------------------------+
 | http://www.cacti.net/                                                   |
 +-------------------------------------------------------------------------+
*/

global $current_user;

require_once('global.php');

if (!isset($config['cacti_db_version'])) {
	$version = get_cacti_db_version();

	$config['cacti_db_version'] = $version;

	if (!defined('CACTI_DB_VERSION')) {
		define('CACTI_DB_VERSION', $version);
	}
} else {
	$version = $config['cacti_db_version'];
}

$auth_method = read_config_option('auth_method');
$cookie_user = false;

/**
 * Check to see if Cacti authentication is disabled
 * and force Local Authentication on if found
 */
check_reset_no_authentication($auth_method);

/**
 * Check to see if the Database Cacti version is different
 * from the installed Cacti version and start the install
 * process if found to be different.
 */
if (is_install_needed() && !defined('IN_CACTI_INSTALL')) {
	header('Location: ' . CACTI_PATH_URL . 'install/');

	exit;
}

/**
 * The logout page does not require authentication
 * so, short cut the process. login_sso.php is the public SAML2/OpenID
 * redirect+callback endpoint: every request to it is, by definition, still
 * unauthenticated, so it must never hit the login-page redirect below.
 */
if (get_current_page() == 'logout.php' || get_current_page() == 'auth_changepassword.php' || get_current_page() == 'auth_resetpassword.php' || get_current_page() == 'login_sso.php') {
	return true;
}

// handle alternate authentication realms
api_plugin_hook_function('auth_alternate_realms');

/**
 * handle change password dialog and auth cookie if not using basic auth
 */
if ($auth_method != AUTH_METHOD_BASIC) {
	if (isset($_SESSION[SESS_CHANGE_PASSWORD])) {
		header('Location: ' . CACTI_PATH_URL . 'auth_changepassword.php?ref=' . rawurlencode(validate_redirect_url($_SERVER['HTTP_REFERER'] ?? '', 'index.php')));
		exit;
	}

	// check for remember me functionality
	if (!isset($_SESSION[SESS_USER_ID])) {
		$cookie_user = check_auth_cookie();

		if ($cookie_user !== false) {
			if (cacti_auth_transition((int) $cookie_user, 'cookie_restore')) {
				$_SESSION[SESS_USER_ID]     = $cookie_user;
				$_SESSION[SESS_USER_AGENT]  = $_SERVER['HTTP_USER_AGENT'];
				$_SESSION[SESS_CLIENT_ADDR] = get_client_addr();
			} else {
				// The account may have been locked after cookie validation.
				clear_auth_cookie();
			}
		}
	}
}

/**
 * Check for basic auth, and if the user has been logged in via the server
 * but their user_id is not set, include the auth_login.php script to
 * process their log in.
 */
if ($auth_method == AUTH_METHOD_BASIC && !isset($_SESSION[SESS_USER_ID])) {
	$username = get_basic_auth_username();

	if ($username !== false) {
		$current_user = db_fetch_row_prepared('SELECT *
			FROM user_auth
			WHERE realm = 2
			AND username = ?',
			[$username]);

		if (cacti_sizeof($current_user)) {
			if ($current_user['enabled'] != 'on') {
				auth_display_custom_error_message(__('Access Denied!  User account disabled.'));

				exit;
			}

			if (!auth_user_has_access($current_user)) {
				auth_display_custom_error_message(__('You do not have access to any area of Cacti.  Contact your administrator.'));

				exit;
			}

			if (!cacti_auth_transition((int) $current_user['id'], 'basic_auth')) {
				auth_display_custom_error_message(__('Access Denied! User account locked.'));

				exit;
			}

			$_SESSION[SESS_USER_ID]     = $current_user['id'];
			$_SESSION[SESS_USER_AGENT]  = $_SERVER['HTTP_USER_AGENT'];
			$_SESSION[SESS_CLIENT_ADDR] = get_client_addr();

			$client_addr = get_client_addr();

			cacti_log("LOGIN: User '" . $current_user['username'] . "' authenticated via Basic Authentication from IP Address '" . $client_addr . "'", false, 'AUTH');

			db_execute_prepared('INSERT IGNORE INTO user_log
				(username, user_id, result, ip, time)
				VALUES (?, ?, 1, ?, NOW())',
				[$username, $current_user['id'], $_SESSION[SESS_CLIENT_ADDR]]);

			// GHSA-4rmr-wvjq-qxc2: fall through to the per-page realm check below
			// instead of returning, so a Basic Auth login still has its
			// authorization verified for the requested page.
		} else {
			require_once(CACTI_PATH_BASE . '/auth_login.php');
		}
	}
}

/**
 * Check to see if Cacti is locked out and if it is, block
 * users from accessing the site until lockout is cleared.
 */
if (CACTI_WEB && isset($_SESSION[SESS_USER_ID])) {
	$lockout = read_config_option('cacti_lockout_status', true);

	if ($lockout != '') {
		$lockout    = json_decode($lockout, true);
		$admin_user = read_config_option('admin_user');
		$enabled    = read_config_option('auth_maint_lockout_type', true);

		if ($lockout['session'] != session_id()) {
			if (($enabled == 0 && $admin_user != $_SESSION[SESS_USER_ID]) || $enabled == 1) {
				general_header();
				print '<h1>' . __('Cacti is Locked Out for Maintenance') . '</h1>';
				print '<p>' . __('The primary Cacti administrator has locked out the Cacti user interface for maintenance for activities such as upgrades.  If you feel this is in error, please contact your Cacti adminnistrator.  This lockout will stay in place for approximately 30 minutes.') . '</p>';
				bottom_footer();

				exit;
			}
		}
	}
}

/**
 * If the special boolean $guest_account is set for a page, then the guest
 * account can be used.  Where this may not be the case is with basic auth
 * where to enter the Cacti website, you must first have a valid account.
 * if that is the case, then use that valid accounts permissions and not
 * the guest account.
 */
if (isset($guest_account)) {
	$guest_user_id = get_guest_account();

	// find guest user
	if (!empty($guest_user_id)) {
		if (empty($_SESSION[SESS_USER_ID])) {
			$_SESSION[SESS_USER_ID]     = $guest_user_id;
			$_SESSION[SESS_USER_AGENT]  = $_SERVER['HTTP_USER_AGENT'];
			$_SESSION[SESS_CLIENT_ADDR] = get_client_addr();
		}

		$current_user = db_fetch_row_prepared('SELECT *
			FROM user_auth
			WHERE id = ?',
			[$_SESSION[SESS_USER_ID]]);

		// GHSA-4rmr-wvjq-qxc2: fall through to the per-page realm check below
		// instead of returning, so the guest account's access to this page is
		// authorized rather than assumed.
	}
}

/**
 * If we are a guest user in a non-guest area, wipe credentials
 * user will be redirected back to the login page.
 */
if (!isset($guest_account) && isset($_SESSION[SESS_USER_ID])) {
	if (get_guest_account() === $_SESSION[SESS_USER_ID]) {
		kill_session_var(SESS_USER_ID);
		cacti_session_destroy();
		cacti_session_start();
	}
}

if (empty($_SESSION[SESS_USER_ID])) {
	if (isset($auth_json) && $auth_json == true) {
		print json_encode(
			[
				'status'       => '500',
				'statusText'   => __('Not Logged In'),
				'responseText' => __('You must be logged in to access this area of Cacti.')
			]
		);
	} elseif (isset($auth_text) && $auth_text == true) {
		// handle graph_image.php to respond with text.
		print __('FATAL: You must be logged in to access this area of Cacti.');
	} else {
		require_once(CACTI_PATH_BASE . '/auth_login.php');
	}

	exit;
} else {
	if (empty($_SESSION[SESS_USER_2FA]) && db_column_exists('user_auth', 'tfa_enabled')) {
		if (read_config_option('secpass_2fa_enabled') == 'on') {
			if (is_2fa_enabled($_SESSION[SESS_USER_ID])) {
				header('Location: ' . CACTI_PATH_URL . 'auth_2fa.php');
				exit;
			} else {
				$_SESSION[SESS_USER_2FA] = time();
			}
		}
	}

	$realm_id = 0;

	if (isset($user_auth_realm_filenames[get_current_page()])) {
		$realm_id = $user_auth_realm_filenames[get_current_page()];
	}

	// Are we upgrading from a version before 1.2 which has the Install/Upgrade realm 26
	if ($realm_id == 26) {
		// See if we can find any users that are allowed to upgrade
		$install_sql_query = '
			SELECT COUNT(*)
			FROM (
				SELECT realm_id
				FROM user_auth_realm AS uar
				WHERE uar.realm_id = ?';

		$install_sql_params = [$realm_id];

		// See if the group realms exist and if so, check if permission exists there too
		if (db_table_exists('user_auth_group_realm') &&
			db_table_exists('user_auth_group') &&
			db_table_exists('user_auth_group_members')) {
			$install_sql_query .= '
				UNION
				SELECT realm_id
				FROM user_auth_group_realm AS uagr
				INNER JOIN user_auth_group_members AS uagm
				ON uagr.group_id=uagm.group_id
				INNER JOIN user_auth_group AS uag
				ON uag.id=uagr.group_id
				WHERE uag.enabled="on"
				AND uagr.realm_id = ?';

			$install_sql_params = array_merge($install_sql_params, [$realm_id]);
		}

		$install_sql_query .= '
			) AS authorized';

		$has_install_user = db_fetch_cell_prepared($install_sql_query, $install_sql_params);

		if (!$has_install_user) {
			/* We did not find any existing users who can upgrade/install so add any admin *
			 * who has access to the system settings (realm 15) by default                 */
			db_execute('INSERT INTO `user_auth_realm` (realm_id, user_id)
				SELECT 26 as realm_id, ua.id
				FROM user_auth ua
				INNER JOIN user_auth_realm uar
				ON uar.user_id=ua.id
				LEFT JOIN user_auth_realm uar2
				ON uar2.user_id=ua.id
				AND uar2.realm_id=26
				WHERE uar.realm_id=15
				AND uar2.user_id IS NULL');
		}
	}

	if ($realm_id > 0) {
		$auth_sql_query = '
			SELECT COUNT(*)
			FROM (
				SELECT realm_id
				FROM user_auth_realm AS uar
				WHERE uar.user_id = ?
				AND uar.realm_id = ?';

		$auth_sql_params = [$_SESSION[SESS_USER_ID], $realm_id];

		/* Because we now expect installation to be done by authorized users, check the group_realm *
		 * exists before using it as this may not be present if upgrading from pre-1.x              */
		if (db_table_exists('user_auth_group_realm') &&
			db_table_exists('user_auth_group') &&
			db_table_exists('user_auth_group_members')) {
			$auth_sql_query .= '
				UNION
				SELECT realm_id
				FROM user_auth_group_realm AS uagr
				INNER JOIN user_auth_group_members AS uagm
				ON uagr.group_id = uagm.group_id
				INNER JOIN user_auth_group AS uag
				ON uag.id = uagr.group_id
				WHERE uag.enabled = "on"
				AND uagm.user_id = ?
				AND uagr.realm_id = ?';

			$auth_sql_params = array_merge($auth_sql_params, [$_SESSION[SESS_USER_ID], $realm_id]);
		}

		$auth_sql_query .= '
			) AS authorized';

		$authorized = db_fetch_cell_prepared($auth_sql_query, $auth_sql_params);
	} else {
		$authorized = false;
	}

	if ($realm_id != -1 && !$authorized) {
		if (api_plugin_hook_function('custom_denied', OPER_MODE_NATIVE) == OPER_MODE_RESKIN) {
			exit;
		}

		if (isset($_SERVER['HTTP_REFERER'])) {
			$goBack = "<td colspan='2' class='center'>[<a href='" . validate_redirect_url($_SERVER['HTTP_REFERER'], $_SERVER['SCRIPT_NAME']) . "'>" . __('Return') . "</a> | <a href='" . CACTI_PATH_URL . "logout.php'>" . __('Login Again') . '</a>]</td>';
		} elseif ($auth_method != AUTH_METHOD_BASIC) {
			$goBack = "<td colspan='2' class='center'>[<a href='" . CACTI_PATH_URL . "logout.php'>" . __('Login Again') . '</a>]</td>';
		} else {
			$goBack = '';
		}

		raise_ajax_permission_denied();

		$title_header = __('Permission Denied');
		$title_body   = '<p>' . __('You are not permitted to access this section of Cacti.') . '</p><p>' . __('If you feel that this is an error. Please contact your Cacti Administrator.');

		if ($realm_id == 26) {
			$title_header = __('Installation In Progress');
			$title_body   = '<p>' . __('There is an Installation or Upgrade in progress.') . '</p><p>' . __('Only Cacti Administrators with Install/Upgrade privilege may login at this time') . '</p>';
		}

		print "<!DOCTYPE html>\n";
		print "<html>\n";
		print "<head>\n";
		html_common_header($title_header);
		print "</head>\n";
		print "<body class='logoutBody'>
		<div class='logoutLeft'></div>
		<div class='logoutCenter'>
			<div class='logoutArea'>
				<div class='cactiLogoutLogo'></div>
				<legend>" . $title_header . "</legend>
				<div class='logoutTitle'>
					" . $title_body . '
					</p>
					<center>' . $goBack . "</center>
				</div>
				<div class='logoutErrors'></div>
			</div>
			<div class='versionInfo'>" . __('Version') . ' ' . $version . ' | ' . COPYRIGHT_YEARS_SHORT . "</div>
		</div>
		<div class='logoutRight'></div>
		<script type='text/javascript' " . CactiSecureHeaders::getNonceAttribute() . ">
		$(function() {
			$('.loginLeft').css('width',parseInt($(window).width()*0.33)+'px');
			$('.loginRight').css('width',parseInt($(window).width()*0.33)+'px');
		});
		</script>\n";
		include_once('global_session.php');
		print "</body>
		</html>\n";

		exit;
	}

	$current_user = db_fetch_row_prepared('SELECT *
		FROM user_auth
		WHERE id = ?',
		[$_SESSION[SESS_USER_ID]]);
}