enrol/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  * This file contains functions used by upgrade and install.
  18  *
  19  * Because this is used during install it should not include additional files.
  20  *
  21  * @package   enrol_lti
  22  * @copyright 2021 Jake Dallimore <jrhdallimore@gmail.com>
  23  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24  */
  25
  26 defined('MOODLE_INTERNAL') || die();
  27
  28 /**
  29  * This function checks if a private key has been generated for this enrolment instance.
  30  *
  31  * If the key does not exist it generates a new one. If the openssl
  32  * extension is not installed or configured properly it returns a warning message.
  33  *
  34  * @return string A warning message if a private key does not exist and cannot be generated.
  35  */
  36 function enrol_lti_verify_private_key() {
  37
  38     $name = 'lti_13_kid';
  39     $key = get_config('enrol_lti', $name);
  40
  41     // If we already generated a valid key, no need to check.
  42     if (empty($key)) {
  43         // Create the private key.
  44         $kid = bin2hex(openssl_random_pseudo_bytes(10));
  45         set_config($name, $kid, 'enrol_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('lti_13_privatekey', $privatekey, 'enrol_lti');
  56         } else {
  57             return get_string('opensslconfiginvalid', 'enrol_lti');
  58         }
  59     }
  60
  61     return '';
  62 }