mod/dfrn_poll.php

   1 <?php
   2
   3 /**
   4  * @file mod/dfrn_poll.php
   5  */
   6
   7 use Friendica\App;
   8 use Friendica\Core\Config;
   9 use Friendica\Core\L10n;
  10 use Friendica\Core\Logger;
  11 use Friendica\Core\System;
  12 use Friendica\Database\DBA;
  13 use Friendica\Module\Login;
  14 use Friendica\Protocol\DFRN;
  15 use Friendica\Protocol\OStatus;
  16 use Friendica\Util\Network;
  17 use Friendica\Util\Strings;
  18 use Friendica\Util\XML;
  19
  20 require_once 'include/items.php';
  21
  22 function dfrn_poll_init(App $a)
  23 {
  24         Login::sessionAuth();
  25
  26         $dfrn_id         = defaults($_GET, 'dfrn_id'        , '');
  27         $type            = defaults($_GET, 'type'           , 'data');
  28         $last_update     = defaults($_GET, 'last_update'    , '');
  29         $destination_url = defaults($_GET, 'destination_url', '');
  30         $challenge       = defaults($_GET, 'challenge'      , '');
  31         $sec             = defaults($_GET, 'sec'            , '');
  32         $dfrn_version    = (float) defaults($_GET, 'dfrn_version'   , 2.0);
  33         $perm            = defaults($_GET, 'perm'           , 'r');
  34         $quiet                   = !empty($_GET['quiet']);
  35
  36         // Possibly it is an OStatus compatible server that requests a user feed
  37         $user_agent = defaults($_SERVER, 'HTTP_USER_AGENT', '');
  38         if (($a->argc > 1) && ($dfrn_id == '') && !strstr($user_agent, 'Friendica')) {
  39                 $nickname = $a->argv[1];
  40                 header("Content-type: application/atom+xml");
  41                 echo OStatus::feed($nickname, $last_update, 10);
  42                 killme();
  43         }
  44
  45         $direction = -1;
  46
  47         if (strpos($dfrn_id, ':') == 1) {
  48                 $direction = intval(substr($dfrn_id, 0, 1));
  49                 $dfrn_id = substr($dfrn_id, 2);
  50         }
  51
  52         $hidewall = false;
  53
  54         if (($dfrn_id === '') && empty($_POST['dfrn_id'])) {
  55                 if (Config::get('system', 'block_public') && !local_user() && !remote_user()) {
  56                         System::httpExit(403);
  57                 }
  58
  59                 $user = '';
  60                 if ($a->argc > 1) {
  61                         $r = q("SELECT `hidewall`,`nickname` FROM `user` WHERE `user`.`nickname` = '%s' LIMIT 1",
  62                                 DBA::escape($a->argv[1])
  63                         );
  64                         if (!$r) {
  65                                 System::httpExit(404);
  66                         }
  67
  68                         $hidewall = ($r[0]['hidewall'] && !local_user());
  69
  70                         $user = $r[0]['nickname'];
  71                 }
  72
  73                 Logger::log('dfrn_poll: public feed request from ' . $_SERVER['REMOTE_ADDR'] . ' for ' . $user);
  74                 header("Content-type: application/atom+xml");
  75                 echo DFRN::feed('', $user, $last_update, 0, $hidewall);
  76                 killme();
  77         }
  78
  79         if (($type === 'profile') && (!strlen($sec))) {
  80                 $sql_extra = '';
  81                 switch ($direction) {
  82                         case -1:
  83                                 $sql_extra = sprintf(" AND ( `dfrn-id` = '%s' OR `issued-id` = '%s' ) ", DBA::escape($dfrn_id), DBA::escape($dfrn_id));
  84                                 $my_id = $dfrn_id;
  85                                 break;
  86                         case 0:
  87                                 $sql_extra = sprintf(" AND `issued-id` = '%s' AND `duplex` = 1 ", DBA::escape($dfrn_id));
  88                                 $my_id = '1:' . $dfrn_id;
  89                                 break;
  90                         case 1:
  91                                 $sql_extra = sprintf(" AND `dfrn-id` = '%s' AND `duplex` = 1 ", DBA::escape($dfrn_id));
  92                                 $my_id = '0:' . $dfrn_id;
  93                                 break;
  94                         default:
  95                                 $a->internalRedirect();
  96                                 break; // NOTREACHED
  97                 }
  98
  99                 $r = q("SELECT `contact`.*, `user`.`username`, `user`.`nickname`
 100                         FROM `contact` LEFT JOIN `user` ON `contact`.`uid` = `user`.`uid`
 101                         WHERE `contact`.`blocked` = 0 AND `contact`.`pending` = 0
 102                         AND `user`.`nickname` = '%s' $sql_extra LIMIT 1",
 103                         DBA::escape($a->argv[1])
 104                 );
 105
 106                 if (DBA::isResult($r)) {
 107                         $s = Network::fetchUrl($r[0]['poll'] . '?dfrn_id=' . $my_id . '&type=profile-check');
 108
 109                         Logger::log("dfrn_poll: old profile returns " . $s, Logger::DATA);
 110
 111                         if (strlen($s)) {
 112                                 $xml = XML::parseString($s);
 113
 114                                 if ((int)$xml->status === 1) {
 115                                         $_SESSION['authenticated'] = 1;
 116                                         if (empty($_SESSION['remote'])) {
 117                                                 $_SESSION['remote'] = [];
 118                                         }
 119
 120                                         $_SESSION['remote'][] = ['cid' => $r[0]['id'], 'uid' => $r[0]['uid'], 'url' => $r[0]['url']];
 121
 122                                         $_SESSION['visitor_id'] = $r[0]['id'];
 123                                         $_SESSION['visitor_home'] = $r[0]['url'];
 124                                         $_SESSION['visitor_handle'] = $r[0]['addr'];
 125                                         $_SESSION['visitor_visiting'] = $r[0]['uid'];
 126                                         $_SESSION['my_url'] = $r[0]['url'];
 127                                         if (!$quiet) {
 128                                                 info(L10n::t('%1$s welcomes %2$s', $r[0]['username'], $r[0]['name']) . EOL);
 129                                         }
 130
 131                                         // Visitors get 1 day session.
 132                                         $session_id = session_id();
 133                                         $expire = time() + 86400;
 134                                         q("UPDATE `session` SET `expire` = '%s' WHERE `sid` = '%s'",
 135                                                 DBA::escape($expire),
 136                                                 DBA::escape($session_id)
 137                                         );
 138                                 }
 139                         }
 140
 141                         $profile = (count($r) > 0 && isset($r[0]['nickname']) ? $r[0]['nickname'] : '');
 142                         if (!empty($destination_url)) {
 143                                 System::externalRedirect($destination_url);
 144                         } else {
 145                                 $a->internalRedirect('profile/' . $profile);
 146                         }
 147                 }
 148                 $a->internalRedirect();
 149         }
 150
 151         if ($type === 'profile-check' && $dfrn_version < 2.2) {
 152                 if ((strlen($challenge)) && (strlen($sec))) {
 153                         DBA::delete('profile_check', ["`expire` < ?", time()]);
 154                         $r = q("SELECT * FROM `profile_check` WHERE `sec` = '%s' ORDER BY `expire` DESC LIMIT 1",
 155                                 DBA::escape($sec)
 156                         );
 157                         if (!DBA::isResult($r)) {
 158                                 System::xmlExit(3, 'No ticket');
 159                                 // NOTREACHED
 160                         }
 161
 162                         $orig_id = $r[0]['dfrn_id'];
 163                         if (strpos($orig_id, ':')) {
 164                                 $orig_id = substr($orig_id, 2);
 165                         }
 166
 167                         $c = q("SELECT * FROM `contact` WHERE `id` = %d LIMIT 1",
 168                                 intval($r[0]['cid'])
 169                         );
 170                         if (!DBA::isResult($c)) {
 171                                 System::xmlExit(3, 'No profile');
 172                         }
 173
 174                         $contact = $c[0];
 175
 176                         $sent_dfrn_id = hex2bin($dfrn_id);
 177                         $challenge = hex2bin($challenge);
 178
 179                         $final_dfrn_id = '';
 180
 181                         if (($contact['duplex']) && strlen($contact['prvkey'])) {
 182                                 openssl_private_decrypt($sent_dfrn_id, $final_dfrn_id, $contact['prvkey']);
 183                                 openssl_private_decrypt($challenge, $decoded_challenge, $contact['prvkey']);
 184                         } else {
 185                                 openssl_public_decrypt($sent_dfrn_id, $final_dfrn_id, $contact['pubkey']);
 186                                 openssl_public_decrypt($challenge, $decoded_challenge, $contact['pubkey']);
 187                         }
 188
 189                         $final_dfrn_id = substr($final_dfrn_id, 0, strpos($final_dfrn_id, '.'));
 190
 191                         if (strpos($final_dfrn_id, ':') == 1) {
 192                                 $final_dfrn_id = substr($final_dfrn_id, 2);
 193                         }
 194
 195                         if ($final_dfrn_id != $orig_id) {
 196                                 Logger::log('profile_check: ' . $final_dfrn_id . ' != ' . $orig_id, Logger::DEBUG);
 197                                 // did not decode properly - cannot trust this site
 198                                 System::xmlExit(3, 'Bad decryption');
 199                         }
 200
 201                         header("Content-type: text/xml");
 202                         echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?><dfrn_poll><status>0</status><challenge>$decoded_challenge</challenge><sec>$sec</sec></dfrn_poll>";
 203                         killme();
 204                         // NOTREACHED
 205                 } else {
 206                         // old protocol
 207                         switch ($direction) {
 208                                 case 1:
 209                                         $dfrn_id = '0:' . $dfrn_id;
 210                                         break;
 211                                 case 0:
 212                                         $dfrn_id = '1:' . $dfrn_id;
 213                                         break;
 214                                 default:
 215                                         break;
 216                         }
 217
 218                         DBA::delete('profile_check', ["`expire` < ?", time()]);
 219                         $r = q("SELECT * FROM `profile_check` WHERE `dfrn_id` = '%s' ORDER BY `expire` DESC",
 220                                 DBA::escape($dfrn_id));
 221                         if (DBA::isResult($r)) {
 222                                 System::xmlExit(1);
 223                                 return; // NOTREACHED
 224                         }
 225                         System::xmlExit(0);
 226                         return; // NOTREACHED
 227                 }
 228         }
 229 }
 230
 231 function dfrn_poll_post(App $a)
 232 {
 233         $dfrn_id      = defaults($_POST, 'dfrn_id'  , '');
 234         $challenge    = defaults($_POST, 'challenge', '');
 235         $url          = defaults($_POST, 'url'      , '');
 236         $sec          = defaults($_POST, 'sec'      , '');
 237         $ptype        = defaults($_POST, 'type'     , '');
 238         $perm         = defaults($_POST, 'perm'     , 'r');
 239         $dfrn_version = !empty($_POST['dfrn_version']) ? (float) $_POST['dfrn_version'] : 2.0;
 240
 241         if ($ptype === 'profile-check') {
 242                 if (strlen($challenge) && strlen($sec)) {
 243                         Logger::log('dfrn_poll: POST: profile-check');
 244
 245                         DBA::delete('profile_check', ["`expire` < ?", time()]);
 246                         $r = q("SELECT * FROM `profile_check` WHERE `sec` = '%s' ORDER BY `expire` DESC LIMIT 1",
 247                                 DBA::escape($sec)
 248                         );
 249                         if (!DBA::isResult($r)) {
 250                                 System::xmlExit(3, 'No ticket');
 251                                 // NOTREACHED
 252                         }
 253
 254                         $orig_id = $r[0]['dfrn_id'];
 255                         if (strpos($orig_id, ':')) {
 256                                 $orig_id = substr($orig_id, 2);
 257                         }
 258
 259                         $c = q("SELECT * FROM `contact` WHERE `id` = %d LIMIT 1",
 260                                 intval($r[0]['cid'])
 261                         );
 262                         if (!DBA::isResult($c)) {
 263                                 System::xmlExit(3, 'No profile');
 264                         }
 265
 266                         $contact = $c[0];
 267
 268                         $sent_dfrn_id = hex2bin($dfrn_id);
 269                         $challenge = hex2bin($challenge);
 270
 271                         $final_dfrn_id = '';
 272
 273                         if ($contact['duplex'] && strlen($contact['prvkey'])) {
 274                                 openssl_private_decrypt($sent_dfrn_id, $final_dfrn_id, $contact['prvkey']);
 275                                 openssl_private_decrypt($challenge, $decoded_challenge, $contact['prvkey']);
 276                         } else {
 277                                 openssl_public_decrypt($sent_dfrn_id, $final_dfrn_id, $contact['pubkey']);
 278                                 openssl_public_decrypt($challenge, $decoded_challenge, $contact['pubkey']);
 279                         }
 280
 281                         $final_dfrn_id = substr($final_dfrn_id, 0, strpos($final_dfrn_id, '.'));
 282
 283                         if (strpos($final_dfrn_id, ':') == 1) {
 284                                 $final_dfrn_id = substr($final_dfrn_id, 2);
 285                         }
 286
 287                         if ($final_dfrn_id != $orig_id) {
 288                                 Logger::log('profile_check: ' . $final_dfrn_id . ' != ' . $orig_id, Logger::DEBUG);
 289                                 // did not decode properly - cannot trust this site
 290                                 System::xmlExit(3, 'Bad decryption');
 291                         }
 292
 293                         header("Content-type: text/xml");
 294                         echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?><dfrn_poll><status>0</status><challenge>$decoded_challenge</challenge><sec>$sec</sec></dfrn_poll>";
 295                         killme();
 296                         // NOTREACHED
 297                 }
 298         }
 299
 300         $direction = -1;
 301         if (strpos($dfrn_id, ':') == 1) {
 302                 $direction = intval(substr($dfrn_id, 0, 1));
 303                 $dfrn_id = substr($dfrn_id, 2);
 304         }
 305
 306         $r = q("SELECT * FROM `challenge` WHERE `dfrn-id` = '%s' AND `challenge` = '%s' LIMIT 1",
 307                 DBA::escape($dfrn_id),
 308                 DBA::escape($challenge)
 309         );
 310
 311         if (!DBA::isResult($r)) {
 312                 killme();
 313         }
 314
 315         $type = $r[0]['type'];
 316         $last_update = $r[0]['last_update'];
 317
 318         DBA::delete('challenge', ['dfrn-id' => $dfrn_id, 'challenge' => $challenge]);
 319
 320         $sql_extra = '';
 321         switch ($direction) {
 322                 case -1:
 323                         $sql_extra = sprintf(" AND `issued-id` = '%s' ", DBA::escape($dfrn_id));
 324                         $my_id = $dfrn_id;
 325                         break;
 326                 case 0:
 327                         $sql_extra = sprintf(" AND `issued-id` = '%s' AND `duplex` = 1 ", DBA::escape($dfrn_id));
 328                         $my_id = '1:' . $dfrn_id;
 329                         break;
 330                 case 1:
 331                         $sql_extra = sprintf(" AND `dfrn-id` = '%s' AND `duplex` = 1 ", DBA::escape($dfrn_id));
 332                         $my_id = '0:' . $dfrn_id;
 333                         break;
 334                 default:
 335                         $a->internalRedirect();
 336                         break; // NOTREACHED
 337         }
 338
 339         $r = q("SELECT * FROM `contact` WHERE `blocked` = 0 AND `pending` = 0 $sql_extra LIMIT 1");
 340         if (!DBA::isResult($r)) {
 341                 killme();
 342         }
 343
 344         $contact = $r[0];
 345         $owner_uid = $r[0]['uid'];
 346         $contact_id = $r[0]['id'];
 347
 348         if ($type === 'reputation' && strlen($url)) {
 349                 $r = q("SELECT * FROM `contact` WHERE `url` = '%s' AND `uid` = %d LIMIT 1",
 350                         DBA::escape($url),
 351                         intval($owner_uid)
 352                 );
 353                 $reputation = 0;
 354                 $text = '';
 355
 356                 if (DBA::isResult($r)) {
 357                         $reputation = $r[0]['rating'];
 358                         $text = $r[0]['reason'];
 359
 360                         if ($r[0]['id'] == $contact_id) { // inquiring about own reputation not allowed
 361                                 $reputation = 0;
 362                                 $text = '';
 363                         }
 364                 }
 365
 366                 echo "<?xml version=\"1.0\" encoding=\"UTF-8\"?>
 367                 <reputation>
 368                         <url>$url</url>
 369                         <rating>$reputation</rating>
 370                         <description>$text</description>
 371                 </reputation>
 372                 ";
 373                 killme();
 374                 // NOTREACHED
 375         } else {
 376                 // Update the writable flag if it changed
 377                 Logger::log('dfrn_poll: post request feed: ' . print_r($_POST, true), Logger::DATA);
 378                 if ($dfrn_version >= 2.21) {
 379                         if ($perm === 'rw') {
 380                                 $writable = 1;
 381                         } else {
 382                                 $writable = 0;
 383                         }
 384
 385                         if ($writable != $contact['writable']) {
 386                                 q("UPDATE `contact` SET `writable` = %d WHERE `id` = %d",
 387                                         intval($writable),
 388                                         intval($contact_id)
 389                                 );
 390                         }
 391                 }
 392
 393                 header("Content-type: application/atom+xml");
 394                 $o = DFRN::feed($dfrn_id, $a->argv[1], $last_update, $direction);
 395                 echo $o;
 396                 killme();
 397         }
 398 }
 399
 400 function dfrn_poll_content(App $a)
 401 {
 402         $dfrn_id         = defaults($_GET, 'dfrn_id'        , '');
 403         $type            = defaults($_GET, 'type'           , 'data');
 404         $last_update     = defaults($_GET, 'last_update'    , '');
 405         $destination_url = defaults($_GET, 'destination_url', '');
 406         $sec             = defaults($_GET, 'sec'            , '');
 407         $dfrn_version    = !empty($_GET['dfrn_version'])    ? (float) $_GET['dfrn_version'] : 2.0;
 408         $quiet           = !empty($_GET['quiet']);
 409
 410         $direction = -1;
 411         if (strpos($dfrn_id, ':') == 1) {
 412                 $direction = intval(substr($dfrn_id, 0, 1));
 413                 $dfrn_id = substr($dfrn_id, 2);
 414         }
 415
 416         if ($dfrn_id != '') {
 417                 // initial communication from external contact
 418                 $hash = Strings::getRandomHex();
 419
 420                 $status = 0;
 421
 422                 DBA::delete('challenge', ["`expire` < ?", time()]);
 423
 424                 if ($type !== 'profile') {
 425                         $r = q("INSERT INTO `challenge` ( `challenge`, `dfrn-id`, `expire` , `type`, `last_update` )
 426                                 VALUES( '%s', '%s', '%s', '%s', '%s' ) ",
 427                                 DBA::escape($hash),
 428                                 DBA::escape($dfrn_id),
 429                                 intval(time() + 60 ),
 430                                 DBA::escape($type),
 431                                 DBA::escape($last_update)
 432                         );
 433                 }
 434
 435                 $sql_extra = '';
 436                 switch ($direction) {
 437                         case -1:
 438                                 if ($type === 'profile') {
 439                                         $sql_extra = sprintf(" AND ( `dfrn-id` = '%s' OR `issued-id` = '%s' ) ", DBA::escape($dfrn_id), DBA::escape($dfrn_id));
 440                                 } else {
 441                                         $sql_extra = sprintf(" AND `issued-id` = '%s' ", DBA::escape($dfrn_id));
 442                                 }
 443
 444                                 $my_id = $dfrn_id;
 445                                 break;
 446                         case 0:
 447                                 $sql_extra = sprintf(" AND `issued-id` = '%s' AND `duplex` = 1 ", DBA::escape($dfrn_id));
 448                                 $my_id = '1:' . $dfrn_id;
 449                                 break;
 450                         case 1:
 451                                 $sql_extra = sprintf(" AND `dfrn-id` = '%s' AND `duplex` = 1 ", DBA::escape($dfrn_id));
 452                                 $my_id = '0:' . $dfrn_id;
 453                                 break;
 454                         default:
 455                                 $a->internalRedirect();
 456                                 break; // NOTREACHED
 457                 }
 458
 459                 $nickname = $a->argv[1];
 460
 461                 $r = q("SELECT `contact`.*, `user`.`username`, `user`.`nickname`
 462                         FROM `contact` LEFT JOIN `user` ON `contact`.`uid` = `user`.`uid`
 463                         WHERE `contact`.`blocked` = 0 AND `contact`.`pending` = 0
 464                         AND `user`.`nickname` = '%s' $sql_extra LIMIT 1",
 465                         DBA::escape($nickname)
 466                 );
 467                 if (DBA::isResult($r)) {
 468                         $challenge = '';
 469                         $encrypted_id = '';
 470                         $id_str = $my_id . '.' . mt_rand(1000, 9999);
 471
 472                         if (($r[0]['duplex'] && strlen($r[0]['pubkey'])) || !strlen($r[0]['prvkey'])) {
 473                                 openssl_public_encrypt($hash, $challenge, $r[0]['pubkey']);
 474                                 openssl_public_encrypt($id_str, $encrypted_id, $r[0]['pubkey']);
 475                         } else {
 476                                 openssl_private_encrypt($hash, $challenge, $r[0]['prvkey']);
 477                                 openssl_private_encrypt($id_str, $encrypted_id, $r[0]['prvkey']);
 478                         }
 479
 480                         $challenge = bin2hex($challenge);
 481                         $encrypted_id = bin2hex($encrypted_id);
 482                 } else {
 483                         $status = 1;
 484                         $challenge = '';
 485                         $encrypted_id = '';
 486                 }
 487
 488                 if (($type === 'profile') && (strlen($sec))) {
 489                         // heluecht: I don't know why we don't fail immediately when the user or contact hadn't been found.
 490                         // Since it doesn't make sense to continue from this point on, we now fail here. This should be safe.
 491                         if (!DBA::isResult($r)) {
 492                                 System::httpExit(404, ["title" => L10n::t('Page not found.')]);
 493                         }
 494
 495                         // URL reply
 496                         if ($dfrn_version < 2.2) {
 497                                 $s = Network::fetchUrl($r[0]['poll']
 498                                         . '?dfrn_id=' . $encrypted_id
 499                                         . '&type=profile-check'
 500                                         . '&dfrn_version=' . DFRN_PROTOCOL_VERSION
 501                                         . '&challenge=' . $challenge
 502                                         . '&sec=' . $sec
 503                                 );
 504                         } else {
 505                                 $s = Network::post($r[0]['poll'], [
 506                                         'dfrn_id' => $encrypted_id,
 507                                         'type' => 'profile-check',
 508                                         'dfrn_version' => DFRN_PROTOCOL_VERSION,
 509                                         'challenge' => $challenge,
 510                                         'sec' => $sec
 511                                 ])->getBody();
 512                         }
 513
 514                         Logger::log("dfrn_poll: sec profile: " . $s, Logger::DATA);
 515
 516                         if (strlen($s) && strstr($s, '<?xml')) {
 517                                 $xml = XML::parseString($s);
 518
 519                                 Logger::log('dfrn_poll: profile: parsed xml: ' . print_r($xml, true), Logger::DATA);
 520
 521                                 Logger::log('dfrn_poll: secure profile: challenge: ' . $xml->challenge . ' expecting ' . $hash);
 522                                 Logger::log('dfrn_poll: secure profile: sec: ' . $xml->sec . ' expecting ' . $sec);
 523
 524                                 if (((int) $xml->status == 0) && ($xml->challenge == $hash) && ($xml->sec == $sec)) {
 525                                         $_SESSION['authenticated'] = 1;
 526                                         if (empty($_SESSION['remote'])) {
 527                                                 $_SESSION['remote'] = [];
 528                                         }
 529
 530                                         $_SESSION['remote'][] = ['cid' => $r[0]['id'], 'uid' => $r[0]['uid'], 'url' => $r[0]['url']];
 531                                         $_SESSION['visitor_id'] = $r[0]['id'];
 532                                         $_SESSION['visitor_home'] = $r[0]['url'];
 533                                         $_SESSION['visitor_visiting'] = $r[0]['uid'];
 534                                         $_SESSION['my_url'] = $r[0]['url'];
 535                                         if (!$quiet) {
 536                                                 info(L10n::t('%1$s welcomes %2$s', $r[0]['username'], $r[0]['name']) . EOL);
 537                                         }
 538
 539                                         // Visitors get 1 day session.
 540                                         $session_id = session_id();
 541                                         $expire = time() + 86400;
 542                                         q("UPDATE `session` SET `expire` = '%s' WHERE `sid` = '%s'",
 543                                                 DBA::escape($expire),
 544                                                 DBA::escape($session_id)
 545                                         );
 546                                 }
 547                         }
 548
 549                         $profile = ((DBA::isResult($r) && $r[0]['nickname']) ? $r[0]['nickname'] : $nickname);
 550
 551                         switch ($destination_url) {
 552                                 case 'profile':
 553                                         $a->internalRedirect('profile/' . $profile . '?f=&tab=profile');
 554                                         break;
 555                                 case 'photos':
 556                                         $a->internalRedirect('photos/' . $profile);
 557                                         break;
 558                                 case 'status':
 559                                 case '':
 560                                         $a->internalRedirect('profile/' . $profile);
 561                                         break;
 562                                 default:
 563                                         $appendix = (strstr($destination_url, '?') ? '&f=&redir=1' : '?f=&redir=1');
 564                                         if (filter_var($url, FILTER_VALIDATE_URL)) {
 565                                                 System::externalRedirect($destination_url . $appendix);
 566                                         } else {
 567                                                 $a->internalRedirect($destination_url . $appendix);
 568                                         }
 569                                         break;
 570                         }
 571                         // NOTREACHED
 572                 } else {
 573                         // XML reply
 574                         header("Content-type: text/xml");
 575                         echo '<?xml version="1.0" encoding="UTF-8"?>' . "\r\n"
 576                                 . '<dfrn_poll>' . "\r\n"
 577                                 . "\t" . '<status>' . $status . '</status>' . "\r\n"
 578                                 . "\t" . '<dfrn_version>' . DFRN_PROTOCOL_VERSION . '</dfrn_version>' . "\r\n"
 579                                 . "\t" . '<dfrn_id>' . $encrypted_id . '</dfrn_id>' . "\r\n"
 580                                 . "\t" . '<challenge>' . $challenge . '</challenge>' . "\r\n"
 581                                 . '</dfrn_poll>' . "\r\n";
 582                         killme();
 583                         // NOTREACHED
 584                 }
 585         }
 586 }