mnet/lib.php

   1 <?php
   2 /**
   3  * Library functions for mnet
   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 require_once $CFG->dirroot.'/mnet/xmlrpc/xmlparser.php';
  11 require_once $CFG->dirroot.'/mnet/peer.php';
  12 require_once $CFG->dirroot.'/mnet/environment.php';
  13
  14 /// CONSTANTS ///////////////////////////////////////////////////////////
  15
  16 define('RPC_OK',                0);
  17 define('RPC_NOSUCHFILE',        1);
  18 define('RPC_NOSUCHCLASS',       2);
  19 define('RPC_NOSUCHFUNCTION',    3);
  20 define('RPC_FORBIDDENFUNCTION', 4);
  21 define('RPC_NOSUCHMETHOD',      5);
  22 define('RPC_FORBIDDENMETHOD',   6);
  23
  24 /**
  25  * Strip extraneous detail from a URL or URI and return the hostname
  26  *
  27  * @param  string  $uri  The URI of a file on the remote computer, optionally
  28  *                       including its http:// prefix like
  29  *                       http://www.example.com/index.html
  30  * @return string        Just the hostname
  31  */
  32 function mnet_get_hostname_from_uri($uri = null) {
  33     $count = preg_match("@^(?:http[s]?://)?([A-Z0-9\-\.]+).*@i", $uri, $matches);
  34     if ($count > 0) return $matches[1];
  35     return false;
  36 }
  37
  38 /**
  39  * Get the remote machine's SSL Cert
  40  *
  41  * @param  string  $uri     The URI of a file on the remote computer, including
  42  *                          its http:// or https:// prefix
  43  * @return string           A PEM formatted SSL Certificate.
  44  */
  45 function mnet_get_public_key($uri, $application=null) {
  46     global $CFG, $DB;
  47     $mnet = get_mnet_environment();
  48     // The key may be cached in the mnet_set_public_key function...
  49     // check this first
  50     $key = mnet_set_public_key($uri);
  51     if ($key != false) {
  52         return $key;
  53     }
  54
  55     if (empty($application)) {
  56         $application = $DB->get_record('mnet_application', array('name'=>'moodle'));
  57     }
  58
  59     $rq = xmlrpc_encode_request('system/keyswap', array($CFG->wwwroot, $mnet->public_key, $application->name), array(
  60         'encoding' => 'utf-8',
  61         'escaping' => 'markup',
  62     ));
  63     $ch = curl_init($uri . $application->xmlrpc_server_url);
  64
  65     curl_setopt($ch, CURLOPT_TIMEOUT, 60);
  66     curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
  67     curl_setopt($ch, CURLOPT_POST, true);
  68     curl_setopt($ch, CURLOPT_USERAGENT, 'Moodle');
  69     curl_setopt($ch, CURLOPT_POSTFIELDS, $rq);
  70     curl_setopt($ch, CURLOPT_HTTPHEADER, array("Content-Type: text/xml charset=UTF-8"));
  71     curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
  72     curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
  73
  74     // check for proxy
  75     if (!empty($CFG->proxyhost) and !is_proxybypass($uri)) {
  76         // SOCKS supported in PHP5 only
  77         if (!empty($CFG->proxytype) and ($CFG->proxytype == 'SOCKS5')) {
  78             if (defined('CURLPROXY_SOCKS5')) {
  79                 curl_setopt($ch, CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5);
  80             } else {
  81                 curl_close($ch);
  82                 print_error( 'socksnotsupported','mnet' );
  83             }
  84         }
  85
  86         curl_setopt($ch, CURLOPT_HTTPPROXYTUNNEL, false);
  87
  88         if (empty($CFG->proxyport)) {
  89             curl_setopt($ch, CURLOPT_PROXY, $CFG->proxyhost);
  90         } else {
  91             curl_setopt($ch, CURLOPT_PROXY, $CFG->proxyhost.':'.$CFG->proxyport);
  92         }
  93
  94         if (!empty($CFG->proxyuser) and !empty($CFG->proxypassword)) {
  95             curl_setopt($ch, CURLOPT_PROXYUSERPWD, $CFG->proxyuser.':'.$CFG->proxypassword);
  96             if (defined('CURLOPT_PROXYAUTH')) {
  97                 // any proxy authentication if PHP 5.1
  98                 curl_setopt($ch, CURLOPT_PROXYAUTH, CURLAUTH_BASIC | CURLAUTH_NTLM);
  99             }
 100         }
 101     }
 102
 103     $res = xmlrpc_decode(curl_exec($ch));
 104
 105     // check for curl errors
 106     $curlerrno = curl_errno($ch);
 107     if ($curlerrno!=0) {
 108         debugging("Request for $uri failed with curl error $curlerrno");
 109     }
 110
 111     // check HTTP error code
 112     $info =  curl_getinfo($ch);
 113     if (!empty($info['http_code']) and ($info['http_code'] != 200)) {
 114         debugging("Request for $uri failed with HTTP code ".$info['http_code']);
 115     }
 116
 117     curl_close($ch);
 118
 119     if (!is_array($res)) { // ! error
 120         $public_certificate = $res;
 121         $credentials=array();
 122         if (strlen(trim($public_certificate))) {
 123             $credentials = openssl_x509_parse($public_certificate);
 124             $host = $credentials['subject']['CN'];
 125             if (array_key_exists( 'subjectAltName', $credentials['subject'])) {
 126                 $host = $credentials['subject']['subjectAltName'];
 127             }
 128             if (strpos($uri, $host) !== false) {
 129                 mnet_set_public_key($uri, $public_certificate);
 130                 return $public_certificate;
 131             }
 132             else {
 133                 debugging("Request for $uri returned public key for different URI - $host");
 134             }
 135         }
 136         else {
 137             debugging("Request for $uri returned empty response");
 138         }
 139     }
 140     else {
 141         debugging( "Request for $uri returned unexpected result");
 142     }
 143     return false;
 144 }
 145
 146 /**
 147  * Store a URI's public key in a static variable, or retrieve the key for a URI
 148  *
 149  * @param  string  $uri  The URI of a file on the remote computer, including its
 150  *                       https:// prefix
 151  * @param  mixed   $key  A public key to store in the array OR null. If the key
 152  *                       is null, the function will return the previously stored
 153  *                       key for the supplied URI, should it exist.
 154  * @return mixed         A public key OR true/false.
 155  */
 156 function mnet_set_public_key($uri, $key = null) {
 157     static $keyarray = array();
 158     if (isset($keyarray[$uri]) && empty($key)) {
 159         return $keyarray[$uri];
 160     } elseif (!empty($key)) {
 161         $keyarray[$uri] = $key;
 162         return true;
 163     }
 164     return false;
 165 }
 166
 167 /**
 168  * Sign a message and return it in an XML-Signature document
 169  *
 170  * This function can sign any content, but it was written to provide a system of
 171  * signing XML-RPC request and response messages. The message will be base64
 172  * encoded, so it does not need to be text.
 173  *
 174  * We compute the SHA1 digest of the message.
 175  * We compute a signature on that digest with our private key.
 176  * We link to the public key that can be used to verify our signature.
 177  * We base64 the message data.
 178  * We identify our wwwroot - this must match our certificate's CN
 179  *
 180  * The XML-RPC document will be parceled inside an XML-SIG document, which holds
 181  * the base64_encoded XML as an object, the SHA1 digest of that document, and a
 182  * signature of that document using the local private key. This signature will
 183  * uniquely identify the RPC document as having come from this server.
 184  *
 185  * See the {@Link http://www.w3.org/TR/xmldsig-core/ XML-DSig spec} at the W3c
 186  * site
 187  *
 188  * @param  string   $message              The data you want to sign
 189  * @param  resource $privatekey           The private key to sign the response with
 190  * @return string                         An XML-DSig document
 191  */
 192 function mnet_sign_message($message, $privatekey = null) {
 193     global $CFG;
 194     $digest = sha1($message);
 195
 196     $mnet = get_mnet_environment();
 197     // If the user hasn't supplied a private key (for example, one of our older,
 198     //  expired private keys, we get the current default private key and use that.
 199     if ($privatekey == null) {
 200         $privatekey = $mnet->get_private_key();
 201     }
 202
 203     // The '$sig' value below is returned by reference.
 204     // We initialize it first to stop my IDE from complaining.
 205     $sig  = '';
 206     $bool = openssl_sign($message, $sig, $privatekey); // TODO: On failure?
 207
 208     $message = '<?xml version="1.0" encoding="iso-8859-1"?>
 209     <signedMessage>
 210         <Signature Id="MoodleSignature" xmlns="http://www.w3.org/2000/09/xmldsig#">
 211             <SignedInfo>
 212                 <CanonicalizationMethod Algorithm="http://www.w3.org/TR/2001/REC-xml-c14n-20010315"/>
 213                 <SignatureMethod Algorithm="http://www.w3.org/2000/09/xmldsig#rsa-sha1"/>
 214                 <Reference URI="#XMLRPC-MSG">
 215                     <DigestMethod Algorithm="http://www.w3.org/2000/09/xmldsig#sha1"/>
 216                     <DigestValue>'.$digest.'</DigestValue>
 217                 </Reference>
 218             </SignedInfo>
 219             <SignatureValue>'.base64_encode($sig).'</SignatureValue>
 220             <KeyInfo>
 221                 <RetrievalMethod URI="'.$CFG->wwwroot.'/mnet/publickey.php"/>
 222             </KeyInfo>
 223         </Signature>
 224         <object ID="XMLRPC-MSG">'.base64_encode($message).'</object>
 225         <wwwroot>'.$mnet->wwwroot.'</wwwroot>
 226         <timestamp>'.time().'</timestamp>
 227     </signedMessage>';
 228     return $message;
 229 }
 230
 231 /**
 232  * Encrypt a message and return it in an XML-Encrypted document
 233  *
 234  * This function can encrypt any content, but it was written to provide a system
 235  * of encrypting XML-RPC request and response messages. The message will be
 236  * base64 encoded, so it does not need to be text - binary data should work.
 237  *
 238  * We compute the SHA1 digest of the message.
 239  * We compute a signature on that digest with our private key.
 240  * We link to the public key that can be used to verify our signature.
 241  * We base64 the message data.
 242  * We identify our wwwroot - this must match our certificate's CN
 243  *
 244  * The XML-RPC document will be parceled inside an XML-SIG document, which holds
 245  * the base64_encoded XML as an object, the SHA1 digest of that document, and a
 246  * signature of that document using the local private key. This signature will
 247  * uniquely identify the RPC document as having come from this server.
 248  *
 249  * See the {@Link http://www.w3.org/TR/xmlenc-core/ XML-ENC spec} at the W3c
 250  * site
 251  *
 252  * @param  string   $message              The data you want to sign
 253  * @param  string   $remote_certificate   Peer's certificate in PEM format
 254  * @return string                         An XML-ENC document
 255  */
 256 function mnet_encrypt_message($message, $remote_certificate) {
 257     $mnet = get_mnet_environment();
 258
 259     // Generate a key resource from the remote_certificate text string
 260     $publickey = openssl_get_publickey($remote_certificate);
 261
 262     if ( gettype($publickey) != 'resource' ) {
 263         // Remote certificate is faulty.
 264         return false;
 265     }
 266
 267     // Initialize vars
 268     $encryptedstring = '';
 269     $symmetric_keys = array();
 270
 271     //        passed by ref ->     &$encryptedstring &$symmetric_keys
 272     $bool = openssl_seal($message, $encryptedstring, $symmetric_keys, array($publickey));
 273     $message = $encryptedstring;
 274     $symmetrickey = array_pop($symmetric_keys);
 275
 276     $message = '<?xml version="1.0" encoding="iso-8859-1"?>
 277     <encryptedMessage>
 278         <EncryptedData Id="ED" xmlns="http://www.w3.org/2001/04/xmlenc#">
 279             <EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#arcfour"/>
 280             <ds:KeyInfo xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
 281                 <ds:RetrievalMethod URI="#EK" Type="http://www.w3.org/2001/04/xmlenc#EncryptedKey"/>
 282                 <ds:KeyName>XMLENC</ds:KeyName>
 283             </ds:KeyInfo>
 284             <CipherData>
 285                 <CipherValue>'.base64_encode($message).'</CipherValue>
 286             </CipherData>
 287         </EncryptedData>
 288         <EncryptedKey Id="EK" xmlns="http://www.w3.org/2001/04/xmlenc#">
 289             <EncryptionMethod Algorithm="http://www.w3.org/2001/04/xmlenc#rsa-1_5"/>
 290             <ds:KeyInfo xmlns:ds="http://www.w3.org/2000/09/xmldsig#">
 291                 <ds:KeyName>SSLKEY</ds:KeyName>
 292             </ds:KeyInfo>
 293             <CipherData>
 294                 <CipherValue>'.base64_encode($symmetrickey).'</CipherValue>
 295             </CipherData>
 296             <ReferenceList>
 297                 <DataReference URI="#ED"/>
 298             </ReferenceList>
 299             <CarriedKeyName>XMLENC</CarriedKeyName>
 300         </EncryptedKey>
 301         <wwwroot>'.$mnet->wwwroot.'</wwwroot>
 302     </encryptedMessage>';
 303     return $message;
 304 }
 305
 306 /**
 307  * Get your SSL keys from the database, or create them (if they don't exist yet)
 308  *
 309  * Get your SSL keys from the database, or (if they don't exist yet) call
 310  * mnet_generate_keypair to create them
 311  *
 312  * @param   string  $string     The text you want to sign
 313  * @return  string              The signature over that text
 314  */
 315 function mnet_get_keypair() {
 316     global $CFG, $DB;
 317     static $keypair = null;
 318     if (!is_null($keypair)) return $keypair;
 319     if ($result = get_config('mnet', 'openssl')) {
 320         list($keypair['certificate'], $keypair['keypair_PEM']) = explode('@@@@@@@@', $result);
 321         $keypair['privatekey'] = openssl_pkey_get_private($keypair['keypair_PEM']);
 322         $keypair['publickey']  = openssl_pkey_get_public($keypair['certificate']);
 323         return $keypair;
 324     } else {
 325         $keypair = mnet_generate_keypair();
 326         return $keypair;
 327     }
 328 }
 329
 330 /**
 331  * Generate public/private keys and store in the config table
 332  *
 333  * Use the distinguished name provided to create a CSR, and then sign that CSR
 334  * with the same credentials. Store the keypair you create in the config table.
 335  * If a distinguished name is not provided, create one using the fullname of
 336  * 'the course with ID 1' as your organization name, and your hostname (as
 337  * detailed in $CFG->wwwroot).
 338  *
 339  * @param   array  $dn  The distinguished name of the server
 340  * @return  string      The signature over that text
 341  */
 342 function mnet_generate_keypair($dn = null, $days=28) {
 343     global $CFG, $USER, $DB;
 344
 345     // check if lifetime has been overriden
 346     if (!empty($CFG->mnetkeylifetime)) {
 347         $days = $CFG->mnetkeylifetime;
 348     }
 349
 350     $host = strtolower($CFG->wwwroot);
 351     $host = preg_replace("~^http(s)?://~",'',$host);
 352     $break = strpos($host.'/' , '/');
 353     $host   = substr($host, 0, $break);
 354
 355     $site = get_site();
 356     $organization = $site->fullname;
 357
 358     $keypair = array();
 359
 360     $country  = 'NZ';
 361     $province = 'Wellington';
 362     $locality = 'Wellington';
 363     $email    = !empty($CFG->noreplyaddress) ? $CFG->noreplyaddress : 'noreply@'.$_SERVER['HTTP_HOST'];
 364
 365     if(!empty($USER->country)) {
 366         $country  = $USER->country;
 367     }
 368     if(!empty($USER->city)) {
 369         $province = $USER->city;
 370         $locality = $USER->city;
 371     }
 372     if(!empty($USER->email)) {
 373         $email    = $USER->email;
 374     }
 375
 376     if (is_null($dn)) {
 377         $dn = array(
 378            "countryName" => $country,
 379            "stateOrProvinceName" => $province,
 380            "localityName" => $locality,
 381            "organizationName" => $organization,
 382            "organizationalUnitName" => 'Moodle',
 383            "commonName" => substr($CFG->wwwroot, 0, 64),
 384            "subjectAltName" => $CFG->wwwroot,
 385            "emailAddress" => $email
 386         );
 387     }
 388
 389     $dnlimits = array(
 390            'countryName'            => 2,
 391            'stateOrProvinceName'    => 128,
 392            'localityName'           => 128,
 393            'organizationName'       => 64,
 394            'organizationalUnitName' => 64,
 395            'commonName'             => 64,
 396            'emailAddress'           => 128
 397     );
 398
 399     foreach ($dnlimits as $key => $length) {
 400         $dn[$key] = core_text::substr($dn[$key], 0, $length);
 401     }
 402
 403     // ensure we remove trailing slashes
 404     $dn["commonName"] = preg_replace(':/$:', '', $dn["commonName"]);
 405     if (!empty($CFG->opensslcnf)) { //allow specification of openssl.cnf especially for Windows installs
 406         $new_key = openssl_pkey_new(array("config" => $CFG->opensslcnf));
 407     } else {
 408         $new_key = openssl_pkey_new();
 409     }
 410     if ($new_key === false) {
 411         // can not generate keys - missing openssl.cnf??
 412         return null;
 413     }
 414     if (!empty($CFG->opensslcnf)) { //allow specification of openssl.cnf especially for Windows installs
 415         $csr_rsc = openssl_csr_new($dn, $new_key, array("config" => $CFG->opensslcnf));
 416         $selfSignedCert = openssl_csr_sign($csr_rsc, null, $new_key, $days, array("config" => $CFG->opensslcnf));
 417     } else {
 418         $csr_rsc = openssl_csr_new($dn, $new_key, array('private_key_bits',2048));
 419         $selfSignedCert = openssl_csr_sign($csr_rsc, null, $new_key, $days);
 420     }
 421     unset($csr_rsc); // Free up the resource
 422
 423     // We export our self-signed certificate to a string.
 424     openssl_x509_export($selfSignedCert, $keypair['certificate']);
 425     openssl_x509_free($selfSignedCert);
 426
 427     // Export your public/private key pair as a PEM encoded string. You
 428     // can protect it with an optional passphrase if you wish.
 429     if (!empty($CFG->opensslcnf)) { //allow specification of openssl.cnf especially for Windows installs
 430         $export = openssl_pkey_export($new_key, $keypair['keypair_PEM'], null, array("config" => $CFG->opensslcnf));
 431     } else {
 432         $export = openssl_pkey_export($new_key, $keypair['keypair_PEM'] /* , $passphrase */);
 433     }
 434     openssl_pkey_free($new_key);
 435     unset($new_key); // Free up the resource
 436
 437     return $keypair;
 438 }
 439
 440
 441 function mnet_update_sso_access_control($username, $mnet_host_id, $accessctrl) {
 442     global $DB;
 443
 444     $mnethost = $DB->get_record('mnet_host', array('id'=>$mnet_host_id));
 445     if ($aclrecord = $DB->get_record('mnet_sso_access_control', array('username'=>$username, 'mnet_host_id'=>$mnet_host_id))) {
 446         // Update.
 447         $aclrecord->accessctrl = $accessctrl;
 448         $DB->update_record('mnet_sso_access_control', $aclrecord);
 449
 450         // Trigger access control updated event.
 451         $params = array(
 452             'objectid' => $aclrecord->id,
 453             'context' => context_system::instance(),
 454             'other' => array(
 455                 'username' => $username,
 456                 'hostname' => $mnethost->name,
 457                 'accessctrl' => $accessctrl
 458             )
 459         );
 460         $event = \core\event\mnet_access_control_updated::create($params);
 461         $event->add_record_snapshot('mnet_host', $mnethost);
 462         $event->trigger();
 463     } else {
 464         // Insert.
 465         $aclrecord = new stdClass();
 466         $aclrecord->username = $username;
 467         $aclrecord->accessctrl = $accessctrl;
 468         $aclrecord->mnet_host_id = $mnet_host_id;
 469         $aclrecord->id = $DB->insert_record('mnet_sso_access_control', $aclrecord);
 470
 471         // Trigger access control created event.
 472         $params = array(
 473             'objectid' => $aclrecord->id,
 474             'context' => context_system::instance(),
 475             'other' => array(
 476                 'username' => $username,
 477                 'hostname' => $mnethost->name,
 478                 'accessctrl' => $accessctrl
 479             )
 480         );
 481         $event = \core\event\mnet_access_control_created::create($params);
 482         $event->add_record_snapshot('mnet_host', $mnethost);
 483         $event->trigger();
 484     }
 485     return true;
 486 }
 487
 488 function mnet_get_peer_host ($mnethostid) {
 489     global $DB;
 490     static $hosts;
 491     if (!isset($hosts[$mnethostid])) {
 492         $host = $DB->get_record('mnet_host', array('id' => $mnethostid));
 493         $hosts[$mnethostid] = $host;
 494     }
 495     return $hosts[$mnethostid];
 496 }
 497
 498 /**
 499  * Inline function to modify a url string so that mnet users are requested to
 500  * log in at their mnet identity provider (if they are not already logged in)
 501  * before ultimately being directed to the original url.
 502  *
 503  * @param string $jumpurl the url which user should initially be directed to.
 504  *     This is a URL associated with a moodle networking peer when it
 505  *     is fulfiling a role as an identity provider (IDP). Different urls for
 506  *     different peers, the jumpurl is formed partly from the IDP's webroot, and
 507  *     partly from a predefined local path within that webwroot.
 508  *     The result of the user hitting this jump url is that they will be asked
 509  *     to login (at their identity provider (if they aren't already)), mnet
 510  *     will prepare the necessary authentication information, then redirect
 511  *     them back to somewhere at the content provider(CP) moodle (this moodle)
 512  * @param array $url array with 2 elements
 513  *     0 - context the url was taken from, possibly just the url, possibly href="url"
 514  *     1 - the destination url
 515  * @return string the url the remote user should be supplied with.
 516  */
 517 function mnet_sso_apply_indirection ($jumpurl, $url) {
 518     global $USER, $CFG;
 519
 520     $localpart='';
 521     $urlparts = parse_url($url[1]);
 522     if($urlparts) {
 523         if (isset($urlparts['path'])) {
 524             $path = $urlparts['path'];
 525             // if our wwwroot has a path component, need to strip that path from beginning of the
 526             // 'localpart' to make it relative to moodle's wwwroot
 527             $wwwrootpath = parse_url($CFG->wwwroot, PHP_URL_PATH);
 528             if (!empty($wwwrootpath) and strpos($path, $wwwrootpath) === 0) {
 529                 $path = substr($path, strlen($wwwrootpath));
 530             }
 531             $localpart .= $path;
 532         }
 533         if (isset($urlparts['query'])) {
 534             $localpart .= '?'.$urlparts['query'];
 535         }
 536         if (isset($urlparts['fragment'])) {
 537             $localpart .= '#'.$urlparts['fragment'];
 538         }
 539     }
 540     $indirecturl = $jumpurl . urlencode($localpart);
 541     //If we matched on more than just a url (ie an html link), return the url to an href format
 542     if ($url[0] != $url[1]) {
 543         $indirecturl = 'href="'.$indirecturl.'"';
 544     }
 545     return $indirecturl;
 546 }
 547
 548 function mnet_get_app_jumppath ($applicationid) {
 549     global $DB;
 550     static $appjumppaths;
 551     if (!isset($appjumppaths[$applicationid])) {
 552         $ssojumpurl = $DB->get_field('mnet_application', 'sso_jump_url', array('id' => $applicationid));
 553         $appjumppaths[$applicationid] = $ssojumpurl;
 554     }
 555     return $appjumppaths[$applicationid];
 556 }
 557
 558
 559 /**
 560  * Output debug information about mnet.  this will go to the <b>error_log</b>.
 561  *
 562  * @param mixed $debugdata this can be a string, or array or object.
 563  * @param int   $debuglevel optional , defaults to 1. bump up for very noisy debug info
 564  */
 565 function mnet_debug($debugdata, $debuglevel=1) {
 566     global $CFG;
 567     $setlevel = get_config('', 'mnet_rpcdebug');
 568     if (empty($setlevel) || $setlevel < $debuglevel) {
 569         return;
 570     }
 571     if (is_object($debugdata)) {
 572         $debugdata = (array)$debugdata;
 573     }
 574     if (is_array($debugdata)) {
 575         mnet_debug('DUMPING ARRAY');
 576         foreach ($debugdata as $key => $value) {
 577             mnet_debug("$key: $value");
 578         }
 579         mnet_debug('END DUMPING ARRAY');
 580         return;
 581     }
 582     $prefix = 'MNET DEBUG ';
 583     if (defined('MNET_SERVER')) {
 584         $prefix .= " (server $CFG->wwwroot";
 585         if ($peer = get_mnet_remote_client() && !empty($peer->wwwroot)) {
 586             $prefix .= ", remote peer " . $peer->wwwroot;
 587         }
 588         $prefix .= ')';
 589     } else {
 590         $prefix .= " (client $CFG->wwwroot) ";
 591     }
 592     error_log("$prefix $debugdata");
 593 }
 594
 595 /**
 596  * Return an array of information about all moodle's profile fields
 597  * which ones are optional, which ones are forced.
 598  * This is used as the basis of providing lists of profile fields to the administrator
 599  * to pick which fields to import/export over MNET
 600  *
 601  * @return array(forced => array, optional => array)
 602  */
 603 function mnet_profile_field_options() {
 604     global $DB;
 605     static $info;
 606     if (!empty($info)) {
 607         return $info;
 608     }
 609
 610     $excludes = array(
 611         'id',              // makes no sense
 612         'mnethostid',      // makes no sense
 613         'timecreated',     // will be set to relative to the host anyway
 614         'timemodified',    // will be set to relative to the host anyway
 615         'auth',            // going to be set to 'mnet'
 616         'deleted',         // we should never get deleted users sent over, but don't send this anyway
 617         'confirmed',       // unconfirmed users can't log in to their home site, all remote users considered confirmed
 618         'password',        // no password for mnet users
 619         'theme',           // handled separately
 620         'lastip',          // will be set to relative to the host anyway
 621     );
 622
 623     // these are the ones that user_not_fully_set_up will complain about
 624     // and also special case ones
 625     $forced = array(
 626         'username',
 627         'email',
 628         'firstname',
 629         'lastname',
 630         'auth',
 631         'wwwroot',
 632         'session.gc_lifetime',
 633         '_mnet_userpicture_timemodified',
 634         '_mnet_userpicture_mimetype',
 635     );
 636
 637     // these are the ones we used to send/receive (pre 2.0)
 638     $legacy = array(
 639         'username',
 640         'email',
 641         'auth',
 642         'deleted',
 643         'firstname',
 644         'lastname',
 645         'city',
 646         'country',
 647         'lang',
 648         'timezone',
 649         'description',
 650         'mailformat',
 651         'maildigest',
 652         'maildisplay',
 653         'htmleditor',
 654         'wwwroot',
 655         'picture',
 656     );
 657
 658     // get a random user record from the database to pull the fields off
 659     $randomuser = $DB->get_record('user', array(), '*', IGNORE_MULTIPLE);
 660     foreach ($randomuser as $key => $discard) {
 661         if (in_array($key, $excludes) || in_array($key, $forced)) {
 662             continue;
 663         }
 664         $fields[$key] = $key;
 665     }
 666     $info = array(
 667         'forced'   => $forced,
 668         'optional' => $fields,
 669         'legacy'   => $legacy,
 670     );
 671     return $info;
 672 }
 673
 674
 675 /**
 676  * Returns information about MNet peers
 677  *
 678  * @param bool $withdeleted should the deleted peers be returned too
 679  * @return array
 680  */
 681 function mnet_get_hosts($withdeleted = false) {
 682     global $CFG, $DB;
 683
 684     $sql = "SELECT h.id, h.deleted, h.wwwroot, h.ip_address, h.name, h.public_key, h.public_key_expires,
 685                    h.transport, h.portno, h.last_connect_time, h.last_log_id, h.applicationid,
 686                    a.name as app_name, a.display_name as app_display_name, a.xmlrpc_server_url
 687               FROM {mnet_host} h
 688               JOIN {mnet_application} a ON h.applicationid = a.id
 689              WHERE h.id <> ?";
 690
 691     if (!$withdeleted) {
 692         $sql .= "  AND h.deleted = 0";
 693     }
 694
 695     $sql .= " ORDER BY h.deleted, h.name, h.id";
 696
 697     return $DB->get_records_sql($sql, array($CFG->mnet_localhost_id));
 698 }
 699
 700
 701 /**
 702  * return an array information about services enabled for the given peer.
 703  * in two modes, fulldata or very basic data.
 704  *
 705  * @param mnet_peer $mnet_peer the peer to get information abut
 706  * @param boolean   $fulldata whether to just return which services are published/subscribed, or more information (defaults to full)
 707  *
 708  * @return array  If $fulldata is false, an array is returned like:
 709  *                publish => array(
 710  *                    serviceid => boolean,
 711  *                    serviceid => boolean,
 712  *                ),
 713  *                subscribe => array(
 714  *                    serviceid => boolean,
 715  *                    serviceid => boolean,
 716  *                )
 717  *                If $fulldata is true, an array is returned like:
 718  *                servicename => array(
 719  *                   apiversion => array(
 720  *                        name           => string
 721  *                        offer          => boolean
 722  *                        apiversion     => int
 723  *                        plugintype     => string
 724  *                        pluginname     => string
 725  *                        hostsubscribes => boolean
 726  *                        hostpublishes  => boolean
 727  *                   ),
 728  *               )
 729  */
 730 function mnet_get_service_info(mnet_peer $mnet_peer, $fulldata=true) {
 731     global $CFG, $DB;
 732
 733     $requestkey = (!empty($fulldata) ? 'fulldata' : 'mydata');
 734
 735     static $cache = array();
 736     if (array_key_exists($mnet_peer->id, $cache)) {
 737         return $cache[$mnet_peer->id][$requestkey];
 738     }
 739
 740     $id_list = $mnet_peer->id;
 741     if (!empty($CFG->mnet_all_hosts_id)) {
 742         $id_list .= ', '.$CFG->mnet_all_hosts_id;
 743     }
 744
 745     $concat = $DB->sql_concat('COALESCE(h2s.id,0) ', ' \'-\' ', ' svc.id', '\'-\'', 'r.plugintype', '\'-\'', 'r.pluginname');
 746
 747     $query = "
 748         SELECT DISTINCT
 749             $concat as id,
 750             svc.id as serviceid,
 751             svc.name,
 752             svc.offer,
 753             svc.apiversion,
 754             r.plugintype,
 755             r.pluginname,
 756             h2s.hostid,
 757             h2s.publish,
 758             h2s.subscribe
 759         FROM
 760             {mnet_service2rpc} s2r,
 761             {mnet_rpc} r,
 762             {mnet_service} svc
 763         LEFT JOIN
 764             {mnet_host2service} h2s
 765         ON
 766             h2s.hostid in ($id_list) AND
 767             h2s.serviceid = svc.id
 768         WHERE
 769             svc.offer = '1' AND
 770             s2r.serviceid = svc.id AND
 771             s2r.rpcid = r.id
 772         ORDER BY
 773             svc.name ASC";
 774
 775     $resultset = $DB->get_records_sql($query);
 776
 777     if (is_array($resultset)) {
 778         $resultset = array_values($resultset);
 779     } else {
 780         $resultset = array();
 781     }
 782
 783     require_once $CFG->dirroot.'/mnet/xmlrpc/client.php';
 784
 785     $remoteservices = array();
 786     if ($mnet_peer->id != $CFG->mnet_all_hosts_id) {
 787         // Create a new request object
 788         $mnet_request = new mnet_xmlrpc_client();
 789
 790         // Tell it the path to the method that we want to execute
 791         $mnet_request->set_method('system/listServices');
 792         $mnet_request->send($mnet_peer);
 793         if (is_array($mnet_request->response)) {
 794             foreach($mnet_request->response as $service) {
 795                 $remoteservices[$service['name']][$service['apiversion']] = $service;
 796             }
 797         }
 798     }
 799
 800     $myservices = array();
 801     $mydata = array();
 802     foreach($resultset as $result) {
 803         $result->hostpublishes  = false;
 804         $result->hostsubscribes = false;
 805         if (isset($remoteservices[$result->name][$result->apiversion])) {
 806             if ($remoteservices[$result->name][$result->apiversion]['publish'] == 1) {
 807                 $result->hostpublishes  = true;
 808             }
 809             if ($remoteservices[$result->name][$result->apiversion]['subscribe'] == 1) {
 810                 $result->hostsubscribes  = true;
 811             }
 812         }
 813
 814         if (empty($myservices[$result->name][$result->apiversion])) {
 815             $myservices[$result->name][$result->apiversion] = array('serviceid' => $result->serviceid,
 816                                                                     'name' => $result->name,
 817                                                                     'offer' => $result->offer,
 818                                                                     'apiversion' => $result->apiversion,
 819                                                                     'plugintype' => $result->plugintype,
 820                                                                     'pluginname' => $result->pluginname,
 821                                                                     'hostsubscribes' => $result->hostsubscribes,
 822                                                                     'hostpublishes' => $result->hostpublishes
 823                                                                     );
 824         }
 825
 826         // allhosts_publish allows us to tell the admin that even though he
 827         // is disabling a service, it's still available to the host because
 828         // he's also publishing it to 'all hosts'
 829         if ($result->hostid == $CFG->mnet_all_hosts_id && $CFG->mnet_all_hosts_id != $mnet_peer->id) {
 830             $myservices[$result->name][$result->apiversion]['allhosts_publish'] = $result->publish;
 831             $myservices[$result->name][$result->apiversion]['allhosts_subscribe'] = $result->subscribe;
 832         } elseif (!empty($result->hostid)) {
 833             $myservices[$result->name][$result->apiversion]['I_publish'] = $result->publish;
 834             $myservices[$result->name][$result->apiversion]['I_subscribe'] = $result->subscribe;
 835         }
 836         $mydata['publish'][$result->serviceid] = $result->publish;
 837         $mydata['subscribe'][$result->serviceid] = $result->subscribe;
 838
 839     }
 840
 841     $cache[$mnet_peer->id]['fulldata'] = $myservices;
 842     $cache[$mnet_peer->id]['mydata'] = $mydata;
 843
 844     return $cache[$mnet_peer->id][$requestkey];
 845 }
 846
 847 /**
 848  * return an array of the profile fields to send
 849  * with user information to the given mnet host.
 850  *
 851  * @param mnet_peer $peer the peer to send the information to
 852  *
 853  * @return array (like 'username', 'firstname', etc)
 854  */
 855 function mnet_fields_to_send(mnet_peer $peer) {
 856     return _mnet_field_helper($peer, 'export');
 857 }
 858
 859 /**
 860  * return an array of the profile fields to import
 861  * from the given host, when creating/updating user accounts
 862  *
 863  * @param mnet_peer $peer the peer we're getting the information from
 864  *
 865  * @return array (like 'username', 'firstname', etc)
 866  */
 867 function mnet_fields_to_import(mnet_peer $peer) {
 868     return _mnet_field_helper($peer, 'import');
 869 }
 870
 871 /**
 872  * helper for {@see mnet_fields_to_import} and {@mnet_fields_to_send}
 873  *
 874  * @access private
 875  *
 876  * @param mnet_peer $peer the peer object
 877  * @param string    $key 'import' or 'export'
 878  *
 879  * @return array (like 'username', 'firstname', etc)
 880  */
 881 function _mnet_field_helper(mnet_peer $peer, $key) {
 882     $tmp = mnet_profile_field_options();
 883     $defaults = explode(',', get_config('moodle', 'mnetprofile' . $key . 'fields'));
 884     if ('1' === get_config('mnet', 'host' . $peer->id . $key . 'default')) {
 885         return array_merge($tmp['forced'], $defaults);
 886     }
 887     $hostsettings = get_config('mnet', 'host' . $peer->id . $key . 'fields');
 888     if (false === $hostsettings) {
 889         return array_merge($tmp['forced'], $defaults);
 890     }
 891     return array_merge($tmp['forced'], explode(',', $hostsettings));
 892 }
 893
 894
 895 /**
 896  * given a user object (or array) and a list of allowed fields,
 897  * strip out all the fields that should not be included.
 898  * This can be used both for outgoing data and incoming data.
 899  *
 900  * @param mixed $user array or object representing a database record
 901  * @param array $fields an array of allowed fields (usually from mnet_fields_to_{send,import}
 902  *
 903  * @return mixed array or object, depending what type of $user object was passed (datatype is respected)
 904  */
 905 function mnet_strip_user($user, $fields) {
 906     if (is_object($user)) {
 907         $user = (array)$user;
 908         $wasobject = true; // so we can cast back before we return
 909     }
 910
 911     foreach ($user as $key => $value) {
 912         if (!in_array($key, $fields)) {
 913             unset($user[$key]);
 914         }
 915     }
 916     if (!empty($wasobject)) {
 917         $user = (object)$user;
 918     }
 919     return $user;
 920 }