mod/lti/upgradelib.php

   1 <?php
   2 // This file is part of Moodle - http://moodle.org/
   3 //
   4 // Moodle is free software: you can redistribute it and/or modify
   5 // it under the terms of the GNU General Public License as published by
   6 // the Free Software Foundation, either version 3 of the License, or
   7 // (at your option) any later version.
   8 //
   9 // Moodle is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13 //
  14 // You should have received a copy of the GNU General Public License
  15 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 /**
  18  * This file contains functions used by upgrade and install.
  19  *
  20  * Because this is used during install it should not include additional files.
  21  *
  22  * @package   mod_lti
  23  * @copyright 2019 Damyon Wiese
  24  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  25  */
  26
  27 defined('MOODLE_INTERNAL') || die();
  28
  29 /**
  30  * This function checks if a private key has been generated for this site.
  31  *
  32  * If the key does not exist it generates a new one. If the openssl
  33  * extension is not installed or configured properly it returns a warning message.
  34  *
  35  * @return string A warning message if a private key does not exist and cannot be generated.
  36  */
  37 function mod_lti_verify_private_key() {
  38     $key = get_config('privatekey', 'mod_lti');
  39
  40     // If we already generated a valid key, no need to check.
  41     if (empty($key)) {
  42
  43         // Create the private key.
  44         $kid = bin2hex(openssl_random_pseudo_bytes(10));
  45         set_config('kid', $kid, 'mod_lti');
  46         $config = array(
  47             "digest_alg" => "sha256",
  48             "private_key_bits" => 2048,
  49             "private_key_type" => OPENSSL_KEYTYPE_RSA,
  50         );
  51         $res = openssl_pkey_new($config);
  52         openssl_pkey_export($res, $privatekey);
  53
  54         if (!empty($privatekey)) {
  55             set_config('privatekey', $privatekey, 'mod_lti');
  56         } else {
  57             return get_string('opensslconfiginvalid', 'mod_lti');
  58         }
  59     }
  60
  61     return '';
  62 }