#!/usr/local/bin/php
<?php

/**
 *    Copyright (C) 2016 Deciso B.V.
 *
 *    All rights reserved.
 *
 *    Redistribution and use in source and binary forms, with or without
 *    modification, are permitted provided that the following conditions are met:
 *
 *    1. Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 *
 *    2. Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *
 *    THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
 *    INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
 *    AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *    AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 *    OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 *    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *    POSSIBILITY OF SUCH DAMAGE.
 *
 */

require_once("config.inc");
require_once("auth.inc");

// parse received auth data (key=value combinations separated by "\0")
//  user=<name>
//  password=<password>
//  service=<pam service> (to be implemented)

$fp = fopen('php://stdin', 'r');
$auth_data = array();
$line = '';

while (($char = fgetc($fp)) !== false) {
    if ($char !== "\0") {
        $line .= $char;
    } elseif (strlen($line)) {
        $parts = explode('=', $line, 2);
        if (count($parts) == 2) {
            $auth_data[$parts[0]] = $parts[1];
        }
        $line = '';
    } else {
        break;
    }
}

$exit_status = -1;
if (!empty($auth_data['user']) && isset($auth_data['password'])) {
    $authcfg = auth_get_authserver("Local Database");
    $authcfg_fallback = auth_get_authserver("Local Database");

    if (isset($config['system']['webgui']['authmode'])) {
        $authcfg = auth_get_authserver($config['system']['webgui']['authmode']);
    }

    if (!empty($config['system']['webgui']['authmode_fallback'])) {
        if ($config['system']['webgui']['authmode_fallback'] == "__NO_FALLBACK__") {
            // no fallback
            $authcfg_fallback = false;
        } else {
            $authcfg_fallback = auth_get_authserver($config['system']['webgui']['authmode_fallback']);
        }
    }

    if (authenticate_user($auth_data['user'], $auth_data['password'], $authcfg)) {
        // auth OK
        syslog(LOG_NOTICE, "user '".$auth_data['user']."' authenticated successfully\n");
        $exit_status = 0;
    } elseif ($authcfg != $authcfg_fallback && $authcfg_fallback !== false &&
      authenticate_user($auth_data['user'], $auth_data['password'], $authcfg_fallback)) {
        // auth OK, using fallback
        syslog(LOG_NOTICE, "user '".$auth_data['user']."' authenticated successfully (using fallback)\n");
        $exit_status = 0;
    } else {
        if (getUserEntry($auth_data['user']) === false) {
            $exit_status = 2;
        }
        syslog(LOG_WARNING, "user '".$auth_data['user']."' could not authenticate.\n");
    }
}

// failed auth, return exit status -1
closelog();

exit($exit_status);
