mnet/xmlrpc/server.php

   1 <?php
   2 /**
   3  * An XML-RPC server
   4  *
   5  * @author  Donal McMullan  donal@catalyst.net.nz
   6  * @version 0.0.1
   7  * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
   8  * @package mnet
   9  */
  10
  11 // Make certain that config.php doesn't display any errors, and that it doesn't
  12 // override our do-not-display-errors setting:
  13 // disable moodle specific debug messages and any errors in output
  14 define('NO_DEBUG_DISPLAY', true);
  15 // cookies are not used, makes sure there is empty global $USER
  16 define('NO_MOODLE_COOKIES', true);
  17
  18 define('MNET_SERVER', true);
  19
  20 require_once(dirname(dirname(dirname(__FILE__))) . '/config.php');
  21
  22 $mnet = get_mnet_environment();
  23 // Include MNET stuff:
  24 require_once $CFG->dirroot.'/mnet/lib.php';
  25 require_once $CFG->dirroot.'/mnet/remote_client.php';
  26 require_once $CFG->dirroot.'/mnet/xmlrpc/serverlib.php';
  27
  28
  29 if ($CFG->mnet_dispatcher_mode === 'off') {
  30     print_error('mnetdisabled', 'mnet');
  31 }
  32
  33 // Content type for output is not html:
  34 header('Content-type: text/xml; charset=utf-8');
  35
  36 // PHP 5.2.2: $HTTP_RAW_POST_DATA not populated bug:
  37 // http://bugs.php.net/bug.php?id=41293
  38 if (empty($HTTP_RAW_POST_DATA)) {
  39     $HTTP_RAW_POST_DATA = file_get_contents('php://input');
  40 }
  41
  42 mnet_debug("HTTP_RAW_POST_DATA", 2);
  43 mnet_debug($HTTP_RAW_POST_DATA, 2);
  44
  45 if (!isset($_SERVER)) {
  46     exit(mnet_server_fault(712, get_string('phperror', 'mnet')));
  47 }
  48
  49
  50 // New global variable which ONLY gets set in this server page, so you know that
  51 // if you've been called by a remote Moodle, this should be set:
  52 $remoteclient = new mnet_remote_client();
  53 set_mnet_remote_client($remoteclient);
  54
  55 try {
  56     $plaintextmessage = mnet_server_strip_encryption($HTTP_RAW_POST_DATA);
  57     $xmlrpcrequest = mnet_server_strip_signature($plaintextmessage);
  58 } catch (Exception $e) {
  59     mnet_debug('encryption strip exception thrown: ' . $e->getMessage());
  60     exit(mnet_server_fault($e->getCode(), $e->getMessage(), $e->a));
  61 }
  62
  63 mnet_debug('XMLRPC Payload', 2);
  64 mnet_debug($xmlrpcrequest, 2);
  65
  66 if($remoteclient->pushkey == true) {
  67     // The peer used one of our older public keys, we will return a
  68     // signed/encrypted error message containing our new public key
  69     // Sign message with our old key, and encrypt to the peer's private key.
  70     mnet_debug('sending back new key');
  71     exit(mnet_server_fault_xml(7025, $mnet->public_key, $remoteclient->useprivatekey));
  72 }
  73 // Have a peek at what the request would be if we were to process it
  74 $params = xmlrpc_decode_request($xmlrpcrequest, $method);
  75 mnet_debug("incoming mnet request $method");
  76
  77 // One of three conditions need to be met before we continue processing this request:
  78 // 1. Request is properly encrypted and signed
  79 // 2. Request is for a keyswap (we don't mind enencrypted or unsigned requests for a public key)
  80 // 3. Request is properly signed and we're happy with it being unencrypted
  81 if ((($remoteclient->request_was_encrypted == true) && ($remoteclient->signatureok == true))
  82     || (($method == 'system.keyswap') || ($method == 'system/keyswap'))
  83     || (($remoteclient->signatureok == true) && ($remoteclient->plaintext_is_ok() == true))) {
  84     try {
  85         // main dispatch call.  will echo the response directly
  86         mnet_server_dispatch($xmlrpcrequest);
  87         mnet_debug('exiting cleanly');
  88         exit;
  89     } catch (Exception $e) {
  90         mnet_debug('dispatch exception thrown: ' . $e->getMessage());
  91         exit(mnet_server_fault($e->getCode(), $e->getMessage(), $e->a));
  92     }
  93 }
  94 // if we get to here, something is wrong
  95 // so detect a few common cases and send appropriate errors
  96 if (($remoteclient->request_was_encrypted == false) && ($remoteclient->plaintext_is_ok() == false)) {
  97     mnet_debug('non encrypted request');
  98     exit(mnet_server_fault(7021, get_string('forbidden-transport', 'mnet')));
  99 }
 100
 101 if ($remoteclient->request_was_signed == false) {
 102     // Request was not signed
 103     mnet_debug('non signed request');
 104     exit(mnet_server_fault(711, get_string('verifysignature-error', 'mnet')));
 105 }
 106
 107 if ($remoteclient->signatureok == false) {
 108     // We were unable to verify the signature
 109     mnet_debug('non verified signature');
 110     exit(mnet_server_fault(710, get_string('verifysignature-invalid', 'mnet')));
 111 }
 112 mnet_debug('unknown error');
 113 exit(mnet_server_fault(7000, get_string('unknownerror', 'mnet')));