src/Model/GServer.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2020, Friendica
   4  *
   5  * @license GNU AGPL version 3 or any later version
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU Affero General Public License as
   9  * published by the Free Software Foundation, either version 3 of the
  10  * License, or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU Affero General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Affero General Public License
  18  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  19  *
  20  */
  21
  22 namespace Friendica\Model;
  23
  24 use DOMDocument;
  25 use DOMXPath;
  26 use Friendica\Core\Protocol;
  27 use Friendica\Core\Worker;
  28 use Friendica\Database\DBA;
  29 use Friendica\DI;
  30 use Friendica\Module\Register;
  31 use Friendica\Network\CurlResult;
  32 use Friendica\Util\Network;
  33 use Friendica\Util\DateTimeFormat;
  34 use Friendica\Util\Strings;
  35 use Friendica\Util\XML;
  36 use Friendica\Core\Logger;
  37 use Friendica\Protocol\PortableContact;
  38 use Friendica\Protocol\Diaspora;
  39 use Friendica\Network\Probe;
  40
  41 /**
  42  * This class handles GServer related functions
  43  */
  44 class GServer
  45 {
  46         // Directory types
  47         const DT_NONE = 0;
  48         const DT_POCO = 1;
  49         const DT_MASTODON = 2;
  50         /**
  51          * Checks if the given server is reachable
  52          *
  53          * @param string  $profile URL of the given profile
  54          * @param string  $server  URL of the given server (If empty, taken from profile)
  55          * @param string  $network Network value that is used, when detection failed
  56          * @param boolean $force   Force an update.
  57          *
  58          * @return boolean 'true' if server seems vital
  59          */
  60         public static function reachable(string $profile, string $server = '', string $network = '', bool $force = false)
  61         {
  62                 if ($server == '') {
  63                         $server = GContact::getBasepath($profile);
  64                 }
  65
  66                 if ($server == '') {
  67                         return true;
  68                 }
  69
  70                 return self::check($server, $network, $force);
  71         }
  72
  73         /**
  74          * Decides if a server needs to be updated, based upon several date fields
  75          *
  76          * @param date $created      Creation date of that server entry
  77          * @param date $updated      When had the server entry be updated
  78          * @param date $last_failure Last failure when contacting that server
  79          * @param date $last_contact Last time the server had been contacted
  80          *
  81          * @return boolean Does the server record needs an update?
  82          */
  83         public static function updateNeeded($created, $updated, $last_failure, $last_contact)
  84         {
  85                 $now = strtotime(DateTimeFormat::utcNow());
  86
  87                 if ($updated > $last_contact) {
  88                         $contact_time = strtotime($updated);
  89                 } else {
  90                         $contact_time = strtotime($last_contact);
  91                 }
  92
  93                 $failure_time = strtotime($last_failure);
  94                 $created_time = strtotime($created);
  95
  96                 // If there is no "created" time then use the current time
  97                 if ($created_time <= 0) {
  98                         $created_time = $now;
  99                 }
 100
 101                 // If the last contact was less than 24 hours then don't update
 102                 if (($now - $contact_time) < (60 * 60 * 24)) {
 103                         return false;
 104                 }
 105
 106                 // If the last failure was less than 24 hours then don't update
 107                 if (($now - $failure_time) < (60 * 60 * 24)) {
 108                         return false;
 109                 }
 110
 111                 // If the last contact was less than a week ago and the last failure is older than a week then don't update
 112                 //if ((($now - $contact_time) < (60 * 60 * 24 * 7)) && ($contact_time > $failure_time))
 113                 //      return false;
 114
 115                 // If the last contact time was more than a week ago and the contact was created more than a week ago, then only try once a week
 116                 if ((($now - $contact_time) > (60 * 60 * 24 * 7)) && (($now - $created_time) > (60 * 60 * 24 * 7)) && (($now - $failure_time) < (60 * 60 * 24 * 7))) {
 117                         return false;
 118                 }
 119
 120                 // If the last contact time was more than a month ago and the contact was created more than a month ago, then only try once a month
 121                 if ((($now - $contact_time) > (60 * 60 * 24 * 30)) && (($now - $created_time) > (60 * 60 * 24 * 30)) && (($now - $failure_time) < (60 * 60 * 24 * 30))) {
 122                         return false;
 123                 }
 124
 125                 return true;
 126         }
 127
 128         /**
 129          * Checks the state of the given server.
 130          *
 131          * @param string  $server_url URL of the given server
 132          * @param string  $network    Network value that is used, when detection failed
 133          * @param boolean $force      Force an update.
 134          *
 135          * @return boolean 'true' if server seems vital
 136          */
 137         public static function check(string $server_url, string $network = '', bool $force = false)
 138         {
 139                 // Unify the server address
 140                 $server_url = trim($server_url, '/');
 141                 $server_url = str_replace('/index.php', '', $server_url);
 142
 143                 if ($server_url == '') {
 144                         return false;
 145                 }
 146
 147                 $gserver = DBA::selectFirst('gserver', [], ['nurl' => Strings::normaliseLink($server_url)]);
 148                 if (DBA::isResult($gserver)) {
 149                         if ($gserver['created'] <= DBA::NULL_DATETIME) {
 150                                 $fields = ['created' => DateTimeFormat::utcNow()];
 151                                 $condition = ['nurl' => Strings::normaliseLink($server_url)];
 152                                 DBA::update('gserver', $fields, $condition);
 153                         }
 154
 155                         $last_contact = $gserver['last_contact'];
 156                         $last_failure = $gserver['last_failure'];
 157
 158                         // See discussion under https://forum.friendi.ca/display/0b6b25a8135aabc37a5a0f5684081633
 159                         // It can happen that a zero date is in the database, but storing it again is forbidden.
 160                         if ($last_contact < DBA::NULL_DATETIME) {
 161                                 $last_contact = DBA::NULL_DATETIME;
 162                         }
 163
 164                         if ($last_failure < DBA::NULL_DATETIME) {
 165                                 $last_failure = DBA::NULL_DATETIME;
 166                         }
 167
 168                         if (!$force && !self::updateNeeded($gserver['created'], '', $last_failure, $last_contact)) {
 169                                 Logger::info('No update needed', ['server' => $server_url]);
 170                                 return ($last_contact >= $last_failure);
 171                         }
 172                         Logger::info('Server is outdated. Start discovery.', ['Server' => $server_url, 'Force' => $force, 'Created' => $gserver['created'], 'Failure' => $last_failure, 'Contact' => $last_contact]);
 173                 } else {
 174                         Logger::info('Server is unknown. Start discovery.', ['Server' => $server_url]);
 175                 }
 176
 177                 return self::detect($server_url, $network);
 178         }
 179
 180         /**
 181          * Detect server data (type, protocol, version number, ...)
 182          * The detected data is then updated or inserted in the gserver table.
 183          *
 184          * @param string  $url     URL of the given server
 185          * @param string  $network Network value that is used, when detection failed
 186          *
 187          * @return boolean 'true' if server could be detected
 188          */
 189         public static function detect(string $url, string $network = '')
 190         {
 191                 Logger::info('Detect server type', ['server' => $url]);
 192                 $serverdata = [];
 193
 194                 $original_url = $url;
 195
 196                 // Remove URL content that is not supposed to exist for a server url
 197                 $urlparts = parse_url($url);
 198                 unset($urlparts['user']);
 199                 unset($urlparts['pass']);
 200                 unset($urlparts['query']);
 201                 unset($urlparts['fragment']);
 202                 $url = Network::unparseURL($urlparts);
 203
 204                 // If the URL missmatches, then we mark the old entry as failure
 205                 if ($url != $original_url) {
 206                         DBA::update('gserver', ['last_failure' => DateTimeFormat::utcNow()], ['nurl' => Strings::normaliseLink($original_url)]);
 207                 }
 208
 209                 // When a nodeinfo is present, we don't need to dig further
 210                 $xrd_timeout = DI::config()->get('system', 'xrd_timeout');
 211                 $curlResult = Network::curl($url . '/.well-known/nodeinfo', false, ['timeout' => $xrd_timeout]);
 212                 if ($curlResult->isTimeout()) {
 213                         DBA::update('gserver', ['last_failure' => DateTimeFormat::utcNow()], ['nurl' => Strings::normaliseLink($url)]);
 214                         return false;
 215                 }
 216
 217                 $nodeinfo = self::fetchNodeinfo($url, $curlResult);
 218
 219                 // When nodeinfo isn't present, we use the older 'statistics.json' endpoint
 220                 if (empty($nodeinfo)) {
 221                         $nodeinfo = self::fetchStatistics($url);
 222                 }
 223
 224                 // If that didn't work out well, we use some protocol specific endpoints
 225                 // For Friendica and Zot based networks we have to dive deeper to reveal more details
 226                 if (empty($nodeinfo['network']) || in_array($nodeinfo['network'], [Protocol::DFRN, Protocol::ZOT])) {
 227                         // Fetch the landing page, possibly it reveals some data
 228                         if (empty($nodeinfo['network'])) {
 229                                 $curlResult = Network::curl($url, false, ['timeout' => $xrd_timeout]);
 230                                 if ($curlResult->isSuccess()) {
 231                                         $serverdata = self::analyseRootHeader($curlResult, $serverdata);
 232                                         $serverdata = self::analyseRootBody($curlResult, $serverdata, $url);
 233                                 }
 234
 235                                 if (!$curlResult->isSuccess() || empty($curlResult->getBody()) || self::invalidBody($curlResult->getBody())) {
 236                                         DBA::update('gserver', ['last_failure' => DateTimeFormat::utcNow()], ['nurl' => Strings::normaliseLink($url)]);
 237                                         return false;
 238                                 }
 239                         }
 240
 241                         if (empty($serverdata['network']) || ($serverdata['network'] == Protocol::ACTIVITYPUB)) {
 242                                 $serverdata = self::detectMastodonAlikes($url, $serverdata);
 243                         }
 244
 245                         // All following checks are done for systems that always have got a "host-meta" endpoint.
 246                         // With this check we don't have to waste time and ressources for dead systems.
 247                         // Also this hopefully prevents us from receiving abuse messages.
 248                         if (empty($serverdata['network']) && !self::validHostMeta($url)) {
 249                                 DBA::update('gserver', ['last_failure' => DateTimeFormat::utcNow()], ['nurl' => Strings::normaliseLink($url)]);
 250                                 return false;
 251                         }
 252
 253                         if (empty($serverdata['network']) || in_array($serverdata['network'], [Protocol::DFRN, Protocol::ACTIVITYPUB])) {
 254                                 $serverdata = self::detectFriendica($url, $serverdata);
 255                         }
 256
 257                         // the 'siteinfo.json' is some specific endpoint of Hubzilla and Red
 258                         if (empty($serverdata['network']) || ($serverdata['network'] == Protocol::ZOT)) {
 259                                 $serverdata = self::fetchSiteinfo($url, $serverdata);
 260                         }
 261
 262                         // The 'siteinfo.json' doesn't seem to be present on older Hubzilla installations
 263                         if (empty($serverdata['network'])) {
 264                                 $serverdata = self::detectHubzilla($url, $serverdata);
 265                         }
 266
 267                         if (empty($serverdata['network'])) {
 268                                 $serverdata = self::detectNextcloud($url, $serverdata);
 269                         }
 270
 271                         if (empty($serverdata['network'])) {
 272                                 $serverdata = self::detectGNUSocial($url, $serverdata);
 273                         }
 274                 } else {
 275                         $serverdata = $nodeinfo;
 276                 }
 277
 278                 // Detect the directory type
 279                 $serverdata['directory-type'] = self::DT_NONE;
 280                 $serverdata = self::checkPoCo($url, $serverdata);
 281                 $serverdata = self::checkMastodonDirectory($url, $serverdata);
 282
 283                 // We can't detect the network type. Possibly it is some system that we don't know yet
 284                 if (empty($serverdata['network'])) {
 285                         $serverdata['network'] = Protocol::PHANTOM;
 286                 }
 287
 288                 // When we hadn't been able to detect the network type, we use the hint from the parameter
 289                 if (($serverdata['network'] == Protocol::PHANTOM) && !empty($network)) {
 290                         $serverdata['network'] = $network;
 291                 }
 292
 293                 $serverdata['url'] = $url;
 294                 $serverdata['nurl'] = Strings::normaliseLink($url);
 295
 296                 // We take the highest number that we do find
 297                 $registeredUsers = $serverdata['registered-users'] ?? 0;
 298
 299                 // On an active server there has to be at least a single user
 300                 if (($serverdata['network'] != Protocol::PHANTOM) && ($registeredUsers == 0)) {
 301                         $registeredUsers = 1;
 302                 }
 303
 304                 if ($serverdata['network'] != Protocol::PHANTOM) {
 305                         $gcontacts = DBA::count('gcontact', ['server_url' => [$url, $serverdata['nurl']]]);
 306                         $apcontacts = DBA::count('apcontact', ['baseurl' => [$url, $serverdata['nurl']]]);
 307                         $contacts = DBA::count('contact', ['uid' => 0, 'baseurl' => [$url, $serverdata['nurl']]]);
 308                         $serverdata['registered-users'] = max($gcontacts, $apcontacts, $contacts, $registeredUsers);
 309                 } else {
 310                         $serverdata['registered-users'] = $registeredUsers;
 311                         $serverdata = self::detectNetworkViaContacts($url, $serverdata);
 312                 }
 313
 314                 $serverdata['last_contact'] = DateTimeFormat::utcNow();
 315
 316                 $gserver = DBA::selectFirst('gserver', ['network'], ['nurl' => Strings::normaliseLink($url)]);
 317                 if (!DBA::isResult($gserver)) {
 318                         $serverdata['created'] = DateTimeFormat::utcNow();
 319                         $ret = DBA::insert('gserver', $serverdata);
 320                 } else {
 321                         // Don't override the network with 'unknown' when there had been a valid entry before
 322                         if (($serverdata['network'] == Protocol::PHANTOM) && !empty($gserver['network'])) {
 323                                 unset($serverdata['network']);
 324                         }
 325
 326                         $ret = DBA::update('gserver', $serverdata, ['nurl' => $serverdata['nurl']]);
 327                 }
 328
 329                 if (!empty($serverdata['network']) && in_array($serverdata['network'], [Protocol::DFRN, Protocol::DIASPORA])) {
 330                         self::discoverRelay($url);
 331                 }
 332
 333                 return $ret;
 334         }
 335
 336         /**
 337          * Fetch relay data from a given server url
 338          *
 339          * @param string $server_url address of the server
 340          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 341          */
 342         private static function discoverRelay(string $server_url)
 343         {
 344                 Logger::info('Discover relay data', ['server' => $server_url]);
 345
 346                 $curlResult = Network::curl($server_url . '/.well-known/x-social-relay');
 347                 if (!$curlResult->isSuccess()) {
 348                         return;
 349                 }
 350
 351                 $data = json_decode($curlResult->getBody(), true);
 352                 if (!is_array($data)) {
 353                         return;
 354                 }
 355
 356                 // Sanitize incoming data, see https://github.com/friendica/friendica/issues/8565
 357                 $data['subscribe'] = (bool)$data['subscribe'] ?? false;
 358
 359                 if (!$data['subscribe'] || empty($data['scope']) || !in_array(strtolower($data['scope']), ['all', 'tags'])) {
 360                         $data['scope'] = '';
 361                         $data['subscribe'] = false;
 362                         $data['tags'] = [];
 363                 }
 364
 365                 $gserver = DBA::selectFirst('gserver', ['id', 'relay-subscribe', 'relay-scope'], ['nurl' => Strings::normaliseLink($server_url)]);
 366                 if (!DBA::isResult($gserver)) {
 367                         return;
 368                 }
 369
 370                 if (($gserver['relay-subscribe'] != $data['subscribe']) || ($gserver['relay-scope'] != $data['scope'])) {
 371                         $fields = ['relay-subscribe' => $data['subscribe'], 'relay-scope' => $data['scope']];
 372                         DBA::update('gserver', $fields, ['id' => $gserver['id']]);
 373                 }
 374
 375                 DBA::delete('gserver-tag', ['gserver-id' => $gserver['id']]);
 376
 377                 if ($data['scope'] == 'tags') {
 378                         // Avoid duplicates
 379                         $tags = [];
 380                         foreach ($data['tags'] as $tag) {
 381                                 $tag = mb_strtolower($tag);
 382                                 if (strlen($tag) < 100) {
 383                                         $tags[$tag] = $tag;
 384                                 }
 385                         }
 386
 387                         foreach ($tags as $tag) {
 388                                 DBA::insert('gserver-tag', ['gserver-id' => $gserver['id'], 'tag' => $tag], true);
 389                         }
 390                 }
 391
 392                 // Create or update the relay contact
 393                 $fields = [];
 394                 if (isset($data['protocols'])) {
 395                         if (isset($data['protocols']['diaspora'])) {
 396                                 $fields['network'] = Protocol::DIASPORA;
 397
 398                                 if (isset($data['protocols']['diaspora']['receive'])) {
 399                                         $fields['batch'] = $data['protocols']['diaspora']['receive'];
 400                                 } elseif (is_string($data['protocols']['diaspora'])) {
 401                                         $fields['batch'] = $data['protocols']['diaspora'];
 402                                 }
 403                         }
 404
 405                         if (isset($data['protocols']['dfrn'])) {
 406                                 $fields['network'] = Protocol::DFRN;
 407
 408                                 if (isset($data['protocols']['dfrn']['receive'])) {
 409                                         $fields['batch'] = $data['protocols']['dfrn']['receive'];
 410                                 } elseif (is_string($data['protocols']['dfrn'])) {
 411                                         $fields['batch'] = $data['protocols']['dfrn'];
 412                                 }
 413                         }
 414                 }
 415                 Diaspora::setRelayContact($server_url, $fields);
 416         }
 417
 418         /**
 419          * Fetch server data from '/statistics.json' on the given server
 420          *
 421          * @param string $url URL of the given server
 422          *
 423          * @return array server data
 424          */
 425         private static function fetchStatistics(string $url)
 426         {
 427                 $curlResult = Network::curl($url . '/statistics.json');
 428                 if (!$curlResult->isSuccess()) {
 429                         return [];
 430                 }
 431
 432                 $data = json_decode($curlResult->getBody(), true);
 433                 if (empty($data)) {
 434                         return [];
 435                 }
 436
 437                 $serverdata = [];
 438
 439                 if (!empty($data['version'])) {
 440                         $serverdata['version'] = $data['version'];
 441                         // Version numbers on statistics.json are presented with additional info, e.g.:
 442                         // 0.6.3.0-p1702cc1c, 0.6.99.0-p1b9ab160 or 3.4.3-2-1191.
 443                         $serverdata['version'] = preg_replace('=(.+)-(.{4,})=ism', '$1', $serverdata['version']);
 444                 }
 445
 446                 if (!empty($data['name'])) {
 447                         $serverdata['site_name'] = $data['name'];
 448                 }
 449
 450                 if (!empty($data['network'])) {
 451                         $serverdata['platform'] = strtolower($data['network']);
 452
 453                         if ($serverdata['platform'] == 'diaspora') {
 454                                 $serverdata['network'] = Protocol::DIASPORA;
 455                         } elseif ($serverdata['platform'] == 'friendica') {
 456                                 $serverdata['network'] = Protocol::DFRN;
 457                         } elseif ($serverdata['platform'] == 'hubzilla') {
 458                                 $serverdata['network'] = Protocol::ZOT;
 459                         } elseif ($serverdata['platform'] == 'redmatrix') {
 460                                 $serverdata['network'] = Protocol::ZOT;
 461                         }
 462                 }
 463
 464
 465                 if (!empty($data['registrations_open'])) {
 466                         $serverdata['register_policy'] = Register::OPEN;
 467                 } else {
 468                         $serverdata['register_policy'] = Register::CLOSED;
 469                 }
 470
 471                 return $serverdata;
 472         }
 473
 474         /**
 475          * Detect server type by using the nodeinfo data
 476          *
 477          * @param string     $url        address of the server
 478          * @param CurlResult $curlResult
 479          * @return array Server data
 480          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 481          */
 482         private static function fetchNodeinfo(string $url, CurlResult $curlResult)
 483         {
 484                 $nodeinfo = json_decode($curlResult->getBody(), true);
 485
 486                 if (!is_array($nodeinfo) || empty($nodeinfo['links'])) {
 487                         return [];
 488                 }
 489
 490                 $nodeinfo1_url = '';
 491                 $nodeinfo2_url = '';
 492
 493                 foreach ($nodeinfo['links'] as $link) {
 494                         if (!is_array($link) || empty($link['rel']) || empty($link['href'])) {
 495                                 Logger::info('Invalid nodeinfo format', ['url' => $url]);
 496                                 continue;
 497                         }
 498                         if ($link['rel'] == 'http://nodeinfo.diaspora.software/ns/schema/1.0') {
 499                                 $nodeinfo1_url = $link['href'];
 500                         } elseif ($link['rel'] == 'http://nodeinfo.diaspora.software/ns/schema/2.0') {
 501                                 $nodeinfo2_url = $link['href'];
 502                         }
 503                 }
 504
 505                 if ($nodeinfo1_url . $nodeinfo2_url == '') {
 506                         return [];
 507                 }
 508
 509                 $server = [];
 510
 511                 // When the nodeinfo url isn't on the same host, then there is obviously something wrong
 512                 if (!empty($nodeinfo2_url) && (parse_url($url, PHP_URL_HOST) == parse_url($nodeinfo2_url, PHP_URL_HOST))) {
 513                         $server = self::parseNodeinfo2($nodeinfo2_url);
 514                 }
 515
 516                 // When the nodeinfo url isn't on the same host, then there is obviously something wrong
 517                 if (empty($server) && !empty($nodeinfo1_url) && (parse_url($url, PHP_URL_HOST) == parse_url($nodeinfo1_url, PHP_URL_HOST))) {
 518                         $server = self::parseNodeinfo1($nodeinfo1_url);
 519                 }
 520
 521                 return $server;
 522         }
 523
 524         /**
 525          * Parses Nodeinfo 1
 526          *
 527          * @param string $nodeinfo_url address of the nodeinfo path
 528          * @return array Server data
 529          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 530          */
 531         private static function parseNodeinfo1(string $nodeinfo_url)
 532         {
 533                 $curlResult = Network::curl($nodeinfo_url);
 534
 535                 if (!$curlResult->isSuccess()) {
 536                         return [];
 537                 }
 538
 539                 $nodeinfo = json_decode($curlResult->getBody(), true);
 540
 541                 if (!is_array($nodeinfo)) {
 542                         return [];
 543                 }
 544
 545                 $server = [];
 546
 547                 $server['register_policy'] = Register::CLOSED;
 548
 549                 if (!empty($nodeinfo['openRegistrations'])) {
 550                         $server['register_policy'] = Register::OPEN;
 551                 }
 552
 553                 if (is_array($nodeinfo['software'])) {
 554                         if (!empty($nodeinfo['software']['name'])) {
 555                                 $server['platform'] = strtolower($nodeinfo['software']['name']);
 556                         }
 557
 558                         if (!empty($nodeinfo['software']['version'])) {
 559                                 $server['version'] = $nodeinfo['software']['version'];
 560                                 // Version numbers on Nodeinfo are presented with additional info, e.g.:
 561                                 // 0.6.3.0-p1702cc1c, 0.6.99.0-p1b9ab160 or 3.4.3-2-1191.
 562                                 $server['version'] = preg_replace('=(.+)-(.{4,})=ism', '$1', $server['version']);
 563                         }
 564                 }
 565
 566                 if (!empty($nodeinfo['metadata']['nodeName'])) {
 567                         $server['site_name'] = $nodeinfo['metadata']['nodeName'];
 568                 }
 569
 570                 if (!empty($nodeinfo['usage']['users']['total'])) {
 571                         $server['registered-users'] = $nodeinfo['usage']['users']['total'];
 572                 }
 573
 574                 if (!empty($nodeinfo['protocols']['inbound']) && is_array($nodeinfo['protocols']['inbound'])) {
 575                         $protocols = [];
 576                         foreach ($nodeinfo['protocols']['inbound'] as $protocol) {
 577                                 $protocols[$protocol] = true;
 578                         }
 579
 580                         if (!empty($protocols['friendica'])) {
 581                                 $server['network'] = Protocol::DFRN;
 582                         } elseif (!empty($protocols['activitypub'])) {
 583                                 $server['network'] = Protocol::ACTIVITYPUB;
 584                         } elseif (!empty($protocols['diaspora'])) {
 585                                 $server['network'] = Protocol::DIASPORA;
 586                         } elseif (!empty($protocols['ostatus'])) {
 587                                 $server['network'] = Protocol::OSTATUS;
 588                         } elseif (!empty($protocols['gnusocial'])) {
 589                                 $server['network'] = Protocol::OSTATUS;
 590                         } elseif (!empty($protocols['zot'])) {
 591                                 $server['network'] = Protocol::ZOT;
 592                         }
 593                 }
 594
 595                 if (empty($server)) {
 596                         return [];
 597                 }
 598
 599                 return $server;
 600         }
 601
 602         /**
 603          * Parses Nodeinfo 2
 604          *
 605          * @param string $nodeinfo_url address of the nodeinfo path
 606          * @return array Server data
 607          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 608          */
 609         private static function parseNodeinfo2(string $nodeinfo_url)
 610         {
 611                 $curlResult = Network::curl($nodeinfo_url);
 612                 if (!$curlResult->isSuccess()) {
 613                         return [];
 614                 }
 615
 616                 $nodeinfo = json_decode($curlResult->getBody(), true);
 617
 618                 if (!is_array($nodeinfo)) {
 619                         return [];
 620                 }
 621
 622                 $server = [];
 623
 624                 $server['register_policy'] = Register::CLOSED;
 625
 626                 if (!empty($nodeinfo['openRegistrations'])) {
 627                         $server['register_policy'] = Register::OPEN;
 628                 }
 629
 630                 if (is_array($nodeinfo['software'])) {
 631                         if (!empty($nodeinfo['software']['name'])) {
 632                                 $server['platform'] = strtolower($nodeinfo['software']['name']);
 633                         }
 634
 635                         if (!empty($nodeinfo['software']['version'])) {
 636                                 $server['version'] = $nodeinfo['software']['version'];
 637                                 // Version numbers on Nodeinfo are presented with additional info, e.g.:
 638                                 // 0.6.3.0-p1702cc1c, 0.6.99.0-p1b9ab160 or 3.4.3-2-1191.
 639                                 $server['version'] = preg_replace('=(.+)-(.{4,})=ism', '$1', $server['version']);
 640                         }
 641                 }
 642
 643                 if (!empty($nodeinfo['metadata']['nodeName'])) {
 644                         $server['site_name'] = $nodeinfo['metadata']['nodeName'];
 645                 }
 646
 647                 if (!empty($nodeinfo['usage']['users']['total'])) {
 648                         $server['registered-users'] = $nodeinfo['usage']['users']['total'];
 649                 }
 650
 651                 if (!empty($nodeinfo['protocols'])) {
 652                         $protocols = [];
 653                         foreach ($nodeinfo['protocols'] as $protocol) {
 654                                 $protocols[$protocol] = true;
 655                         }
 656
 657                         if (!empty($protocols['dfrn'])) {
 658                                 $server['network'] = Protocol::DFRN;
 659                         } elseif (!empty($protocols['activitypub'])) {
 660                                 $server['network'] = Protocol::ACTIVITYPUB;
 661                         } elseif (!empty($protocols['diaspora'])) {
 662                                 $server['network'] = Protocol::DIASPORA;
 663                         } elseif (!empty($protocols['ostatus'])) {
 664                                 $server['network'] = Protocol::OSTATUS;
 665                         } elseif (!empty($protocols['gnusocial'])) {
 666                                 $server['network'] = Protocol::OSTATUS;
 667                         } elseif (!empty($protocols['zot'])) {
 668                                 $server['network'] = Protocol::ZOT;
 669                         }
 670                 }
 671
 672                 if (empty($server)) {
 673                         return [];
 674                 }
 675
 676                 return $server;
 677         }
 678
 679         /**
 680          * Fetch server information from a 'siteinfo.json' file on the given server
 681          *
 682          * @param string $url        URL of the given server
 683          * @param array  $serverdata array with server data
 684          *
 685          * @return array server data
 686          */
 687         private static function fetchSiteinfo(string $url, array $serverdata)
 688         {
 689                 $curlResult = Network::curl($url . '/siteinfo.json');
 690                 if (!$curlResult->isSuccess()) {
 691                         return $serverdata;
 692                 }
 693
 694                 $data = json_decode($curlResult->getBody(), true);
 695                 if (empty($data)) {
 696                         return $serverdata;
 697                 }
 698
 699                 if (!empty($data['url'])) {
 700                         $serverdata['platform'] = strtolower($data['platform']);
 701                         $serverdata['version'] = $data['version'];
 702                 }
 703
 704                 if (!empty($data['plugins'])) {
 705                         if (in_array('pubcrawl', $data['plugins'])) {
 706                                 $serverdata['network'] = Protocol::ACTIVITYPUB;
 707                         } elseif (in_array('diaspora', $data['plugins'])) {
 708                                 $serverdata['network'] = Protocol::DIASPORA;
 709                         } elseif (in_array('gnusoc', $data['plugins'])) {
 710                                 $serverdata['network'] = Protocol::OSTATUS;
 711                         } else {
 712                                 $serverdata['network'] = Protocol::ZOT;
 713                         }
 714                 }
 715
 716                 if (!empty($data['site_name'])) {
 717                         $serverdata['site_name'] = $data['site_name'];
 718                 }
 719
 720                 if (!empty($data['channels_total'])) {
 721                         $serverdata['registered-users'] = $data['channels_total'];
 722                 }
 723
 724                 if (!empty($data['register_policy'])) {
 725                         switch ($data['register_policy']) {
 726                                 case 'REGISTER_OPEN':
 727                                         $serverdata['register_policy'] = Register::OPEN;
 728                                         break;
 729
 730                                 case 'REGISTER_APPROVE':
 731                                         $serverdata['register_policy'] = Register::APPROVE;
 732                                         break;
 733
 734                                 case 'REGISTER_CLOSED':
 735                                 default:
 736                                         $serverdata['register_policy'] = Register::CLOSED;
 737                                         break;
 738                         }
 739                 }
 740
 741                 return $serverdata;
 742         }
 743
 744         /**
 745          * Checks if the server contains a valid host meta file
 746          *
 747          * @param string $url URL of the given server
 748          *
 749          * @return boolean 'true' if the server seems to be vital
 750          */
 751         private static function validHostMeta(string $url)
 752         {
 753                 $xrd_timeout = DI::config()->get('system', 'xrd_timeout');
 754                 $curlResult = Network::curl($url . '/.well-known/host-meta', false, ['timeout' => $xrd_timeout]);
 755                 if (!$curlResult->isSuccess()) {
 756                         return false;
 757                 }
 758
 759                 $xrd = XML::parseString($curlResult->getBody());
 760                 if (!is_object($xrd)) {
 761                         return false;
 762                 }
 763
 764                 $elements = XML::elementToArray($xrd);
 765                 if (empty($elements) || empty($elements['xrd']) || empty($elements['xrd']['link'])) {
 766                         return false;
 767                 }
 768
 769                 $valid = false;
 770                 foreach ($elements['xrd']['link'] as $link) {
 771                         // When there is more than a single "link" element, the array looks slightly different
 772                         if (!empty($link['@attributes'])) {
 773                                 $link = $link['@attributes'];
 774                         }
 775
 776                         if (empty($link['rel']) || empty($link['template'])) {
 777                                 continue;
 778                         }
 779
 780                         if ($link['rel'] == 'lrdd') {
 781                                 // When the webfinger host is the same like the system host, it should be ok.
 782                                 $valid = (parse_url($url, PHP_URL_HOST) == parse_url($link['template'], PHP_URL_HOST));
 783                         }
 784                 }
 785
 786                 return $valid;
 787         }
 788
 789         /**
 790          * Detect the network of the given server via their known contacts
 791          *
 792          * @param string $url        URL of the given server
 793          * @param array  $serverdata array with server data
 794          *
 795          * @return array server data
 796          */
 797         private static function detectNetworkViaContacts(string $url, array $serverdata)
 798         {
 799                 $contacts = [];
 800
 801                 $gcontacts = DBA::select('gcontact', ['url', 'nurl'], ['server_url' => [$url, $serverdata['nurl']]]);
 802                 while ($gcontact = DBA::fetch($gcontacts)) {
 803                         $contacts[$gcontact['nurl']] = $gcontact['url'];
 804                 }
 805                 DBA::close($gcontacts);
 806
 807                 $apcontacts = DBA::select('apcontact', ['url'], ['baseurl' => [$url, $serverdata['nurl']]]);
 808                 while ($apcontact = DBA::fetch($apcontacts)) {
 809                         $contacts[Strings::normaliseLink($apcontact['url'])] = $apcontact['url'];
 810                 }
 811                 DBA::close($apcontacts);
 812
 813                 $pcontacts = DBA::select('contact', ['url', 'nurl'], ['uid' => 0, 'baseurl' => [$url, $serverdata['nurl']]]);
 814                 while ($pcontact = DBA::fetch($pcontacts)) {
 815                         $contacts[$pcontact['nurl']] = $pcontact['url'];
 816                 }
 817                 DBA::close($pcontacts);
 818
 819                 if (empty($contacts)) {
 820                         return $serverdata;
 821                 }
 822
 823                 foreach ($contacts as $contact) {
 824                         $probed = Probe::uri($contact);
 825                         if (in_array($probed['network'], Protocol::FEDERATED)) {
 826                                 $serverdata['network'] = $probed['network'];
 827                                 break;
 828                         }
 829                 }
 830
 831                 $serverdata['registered-users'] = max($serverdata['registered-users'], count($contacts));
 832
 833                 return $serverdata;
 834         }
 835
 836         /**
 837          * Checks if the given server does have a '/poco' endpoint.
 838          * This is used for the 'PortableContact' functionality,
 839          * which is used by both Friendica and Hubzilla.
 840          *
 841          * @param string $url        URL of the given server
 842          * @param array  $serverdata array with server data
 843          *
 844          * @return array server data
 845          */
 846         private static function checkPoCo(string $url, array $serverdata)
 847         {
 848                 $serverdata['poco'] = '';
 849
 850                 $curlResult = Network::curl($url. '/poco');
 851                 if (!$curlResult->isSuccess()) {
 852                         return $serverdata;
 853                 }
 854
 855                 $data = json_decode($curlResult->getBody(), true);
 856                 if (empty($data)) {
 857                         return $serverdata;
 858                 }
 859
 860                 if (!empty($data['totalResults'])) {
 861                         $registeredUsers = $serverdata['registered-users'] ?? 0;
 862                         $serverdata['registered-users'] = max($data['totalResults'], $registeredUsers);
 863                         $serverdata['directory-type'] = self::DT_POCO;
 864                         $serverdata['poco'] = $url . '/poco';
 865                 }
 866
 867                 return $serverdata;
 868         }
 869
 870         /**
 871          * Checks if the given server does have a Mastodon style directory endpoint.
 872          *
 873          * @param string $url        URL of the given server
 874          * @param array  $serverdata array with server data
 875          *
 876          * @return array server data
 877          */
 878         public static function checkMastodonDirectory(string $url, array $serverdata)
 879         {
 880                 $curlResult = Network::curl($url . '/api/v1/directory?limit=1');
 881                 if (!$curlResult->isSuccess()) {
 882                         return $serverdata;
 883                 }
 884
 885                 $data = json_decode($curlResult->getBody(), true);
 886                 if (empty($data)) {
 887                         return $serverdata;
 888                 }
 889
 890                 if (count($data) == 1) {
 891                         $serverdata['directory-type'] = self::DT_MASTODON;
 892                 }
 893
 894                 return $serverdata;
 895         }
 896
 897         /**
 898          * Detects the version number of a given server when it was a NextCloud installation
 899          *
 900          * @param string $url        URL of the given server
 901          * @param array  $serverdata array with server data
 902          *
 903          * @return array server data
 904          */
 905         private static function detectNextcloud(string $url, array $serverdata)
 906         {
 907                 $curlResult = Network::curl($url . '/status.php');
 908
 909                 if (!$curlResult->isSuccess() || ($curlResult->getBody() == '')) {
 910                         return $serverdata;
 911                 }
 912
 913                 $data = json_decode($curlResult->getBody(), true);
 914                 if (empty($data)) {
 915                         return $serverdata;
 916                 }
 917
 918                 if (!empty($data['version'])) {
 919                         $serverdata['platform'] = 'nextcloud';
 920                         $serverdata['version'] = $data['version'];
 921                         $serverdata['network'] = Protocol::ACTIVITYPUB;
 922                 }
 923
 924                 return $serverdata;
 925         }
 926
 927         /**
 928          * Detects data from a given server url if it was a mastodon alike system
 929          *
 930          * @param string $url        URL of the given server
 931          * @param array  $serverdata array with server data
 932          *
 933          * @return array server data
 934          */
 935         private static function detectMastodonAlikes(string $url, array $serverdata)
 936         {
 937                 $curlResult = Network::curl($url . '/api/v1/instance');
 938
 939                 if (!$curlResult->isSuccess() || ($curlResult->getBody() == '')) {
 940                         return $serverdata;
 941                 }
 942
 943                 $data = json_decode($curlResult->getBody(), true);
 944                 if (empty($data)) {
 945                         return $serverdata;
 946                 }
 947
 948                 if (!empty($data['version'])) {
 949                         $serverdata['platform'] = 'mastodon';
 950                         $serverdata['version'] = $data['version'] ?? '';
 951                         $serverdata['network'] = Protocol::ACTIVITYPUB;
 952                 }
 953
 954                 if (!empty($data['title'])) {
 955                         $serverdata['site_name'] = $data['title'];
 956                 }
 957
 958                 if (!empty($data['title']) && empty($serverdata['platform']) && empty($serverdata['network'])) {
 959                         $serverdata['platform'] = 'mastodon';
 960                         $serverdata['network'] = Protocol::ACTIVITYPUB;
 961                 }
 962
 963                 if (!empty($data['description'])) {
 964                         $serverdata['info'] = trim($data['description']);
 965                 }
 966
 967                 if (!empty($data['stats']['user_count'])) {
 968                         $serverdata['registered-users'] = $data['stats']['user_count'];
 969                 }
 970
 971                 if (!empty($serverdata['version']) && preg_match('/.*?\(compatible;\s(.*)\s(.*)\)/ism', $serverdata['version'], $matches)) {
 972                         $serverdata['platform'] = strtolower($matches[1]);
 973                         $serverdata['version'] = $matches[2];
 974                 }
 975
 976                 if (!empty($serverdata['version']) && strstr(strtolower($serverdata['version']), 'pleroma')) {
 977                         $serverdata['platform'] = 'pleroma';
 978                         $serverdata['version'] = trim(str_ireplace('pleroma', '', $serverdata['version']));
 979                 }
 980
 981                 if (!empty($serverdata['platform']) && strstr($serverdata['platform'], 'pleroma')) {
 982                         $serverdata['version'] = trim(str_ireplace('pleroma', '', $serverdata['platform']));
 983                         $serverdata['platform'] = 'pleroma';
 984                 }
 985
 986                 return $serverdata;
 987         }
 988
 989         /**
 990          * Detects data from typical Hubzilla endpoints
 991          *
 992          * @param string $url        URL of the given server
 993          * @param array  $serverdata array with server data
 994          *
 995          * @return array server data
 996          */
 997         private static function detectHubzilla(string $url, array $serverdata)
 998         {
 999                 $curlResult = Network::curl($url . '/api/statusnet/config.json');
1000                 if (!$curlResult->isSuccess() || ($curlResult->getBody() == '')) {
1001                         return $serverdata;
1002                 }
1003
1004                 $data = json_decode($curlResult->getBody(), true);
1005                 if (empty($data)) {
1006                         return $serverdata;
1007                 }
1008
1009                 if (!empty($data['site']['name'])) {
1010                         $serverdata['site_name'] = $data['site']['name'];
1011                 }
1012
1013                 if (!empty($data['site']['platform'])) {
1014                         $serverdata['platform'] = strtolower($data['site']['platform']['PLATFORM_NAME']);
1015                         $serverdata['version'] = $data['site']['platform']['STD_VERSION'];
1016                         $serverdata['network'] = Protocol::ZOT;
1017                 }
1018
1019                 if (!empty($data['site']['hubzilla'])) {
1020                         $serverdata['platform'] = strtolower($data['site']['hubzilla']['PLATFORM_NAME']);
1021                         $serverdata['version'] = $data['site']['hubzilla']['RED_VERSION'];
1022                         $serverdata['network'] = Protocol::ZOT;
1023                 }
1024
1025                 if (!empty($data['site']['redmatrix'])) {
1026                         if (!empty($data['site']['redmatrix']['PLATFORM_NAME'])) {
1027                                 $serverdata['platform'] = strtolower($data['site']['redmatrix']['PLATFORM_NAME']);
1028                         } elseif (!empty($data['site']['redmatrix']['RED_PLATFORM'])) {
1029                                 $serverdata['platform'] = strtolower($data['site']['redmatrix']['RED_PLATFORM']);
1030                         }
1031
1032                         $serverdata['version'] = $data['site']['redmatrix']['RED_VERSION'];
1033                         $serverdata['network'] = Protocol::ZOT;
1034                 }
1035
1036                 $private = false;
1037                 $inviteonly = false;
1038                 $closed = false;
1039
1040                 if (!empty($data['site']['closed'])) {
1041                         $closed = self::toBoolean($data['site']['closed']);
1042                 }
1043
1044                 if (!empty($data['site']['private'])) {
1045                         $private = self::toBoolean($data['site']['private']);
1046                 }
1047
1048                 if (!empty($data['site']['inviteonly'])) {
1049                         $inviteonly = self::toBoolean($data['site']['inviteonly']);
1050                 }
1051
1052                 if (!$closed && !$private and $inviteonly) {
1053                         $register_policy = Register::APPROVE;
1054                 } elseif (!$closed && !$private) {
1055                         $register_policy = Register::OPEN;
1056                 } else {
1057                         $register_policy = Register::CLOSED;
1058                 }
1059
1060                 return $serverdata;
1061         }
1062
1063         /**
1064          * Converts input value to a boolean value
1065          *
1066          * @param string|integer $val
1067          *
1068          * @return boolean
1069          */
1070         private static function toBoolean($val)
1071         {
1072                 if (($val == 'true') || ($val == 1)) {
1073                         return true;
1074                 } elseif (($val == 'false') || ($val == 0)) {
1075                         return false;
1076                 }
1077
1078                 return $val;
1079         }
1080
1081         /**
1082          * Detect if the URL belongs to a GNU Social server
1083          *
1084          * @param string $url        URL of the given server
1085          * @param array  $serverdata array with server data
1086          *
1087          * @return array server data
1088          */
1089         private static function detectGNUSocial(string $url, array $serverdata)
1090         {
1091                 // Test for GNU Social
1092                 $curlResult = Network::curl($url . '/api/gnusocial/version.json');
1093                 if ($curlResult->isSuccess() && ($curlResult->getBody() != '{"error":"not implemented"}') &&
1094                         ($curlResult->getBody() != '') && (strlen($curlResult->getBody()) < 30)) {
1095                         $serverdata['platform'] = 'gnusocial';
1096                         // Remove junk that some GNU Social servers return
1097                         $serverdata['version'] = str_replace(chr(239) . chr(187) . chr(191), '', $curlResult->getBody());
1098                         $serverdata['version'] = str_replace(["\r", "\n", "\t"], '', $serverdata['version']);
1099                         $serverdata['version'] = trim($serverdata['version'], '"');
1100                         $serverdata['network'] = Protocol::OSTATUS;
1101                         return $serverdata;
1102                 }
1103
1104                 // Test for Statusnet
1105                 $curlResult = Network::curl($url . '/api/statusnet/version.json');
1106                 if ($curlResult->isSuccess() && ($curlResult->getBody() != '{"error":"not implemented"}') &&
1107                         ($curlResult->getBody() != '') && (strlen($curlResult->getBody()) < 30)) {
1108
1109                         // Remove junk that some GNU Social servers return
1110                         $serverdata['version'] = str_replace(chr(239).chr(187).chr(191), '', $curlResult->getBody());
1111                         $serverdata['version'] = str_replace(["\r", "\n", "\t"], '', $serverdata['version']);
1112                         $serverdata['version'] = trim($serverdata['version'], '"');
1113
1114                         if (!empty($serverdata['version']) && strtolower(substr($serverdata['version'], 0, 7)) == 'pleroma') {
1115                                 $serverdata['platform'] = 'pleroma';
1116                                 $serverdata['version'] = trim(str_ireplace('pleroma', '', $serverdata['version']));
1117                                 $serverdata['network'] = Protocol::ACTIVITYPUB;
1118                         } else {
1119                                 $serverdata['platform'] = 'statusnet';
1120                                 $serverdata['network'] = Protocol::OSTATUS;
1121                         }
1122                 }
1123
1124                 return $serverdata;
1125         }
1126
1127         /**
1128          * Detect if the URL belongs to a Friendica server
1129          *
1130          * @param string $url        URL of the given server
1131          * @param array  $serverdata array with server data
1132          *
1133          * @return array server data
1134          */
1135         private static function detectFriendica(string $url, array $serverdata)
1136         {
1137                 $curlResult = Network::curl($url . '/friendica/json');
1138                 if (!$curlResult->isSuccess()) {
1139                         $curlResult = Network::curl($url . '/friendika/json');
1140                 }
1141
1142                 if (!$curlResult->isSuccess()) {
1143                         return $serverdata;
1144                 }
1145
1146                 $data = json_decode($curlResult->getBody(), true);
1147                 if (empty($data) || empty($data['version'])) {
1148                         return $serverdata;
1149                 }
1150
1151                 $serverdata['network'] = Protocol::DFRN;
1152                 $serverdata['version'] = $data['version'];
1153
1154                 if (!empty($data['no_scrape_url'])) {
1155                         $serverdata['noscrape'] = $data['no_scrape_url'];
1156                 }
1157
1158                 if (!empty($data['site_name'])) {
1159                         $serverdata['site_name'] = $data['site_name'];
1160                 }
1161
1162                 if (!empty($data['info'])) {
1163                         $serverdata['info'] = trim($data['info']);
1164                 }
1165
1166                 $register_policy = ($data['register_policy'] ?? '') ?: 'REGISTER_CLOSED';
1167                 switch ($register_policy) {
1168                         case 'REGISTER_OPEN':
1169                                 $serverdata['register_policy'] = Register::OPEN;
1170                                 break;
1171
1172                         case 'REGISTER_APPROVE':
1173                                 $serverdata['register_policy'] = Register::APPROVE;
1174                                 break;
1175
1176                         case 'REGISTER_CLOSED':
1177                         case 'REGISTER_INVITATION':
1178                                 $serverdata['register_policy'] = Register::CLOSED;
1179                                 break;
1180                         default:
1181                                 Logger::info('Register policy is invalid', ['policy' => $register_policy, 'server' => $url]);
1182                                 $serverdata['register_policy'] = Register::CLOSED;
1183                                 break;
1184                 }
1185
1186                 $serverdata['platform'] = strtolower($data['platform'] ?? '');
1187
1188                 return $serverdata;
1189         }
1190
1191         /**
1192          * Analyses the landing page of a given server for hints about type and system of that server
1193          *
1194          * @param object $curlResult result of curl execution
1195          * @param array  $serverdata array with server data
1196          * @param string $url        Server URL
1197          *
1198          * @return array server data
1199          */
1200         private static function analyseRootBody($curlResult, array $serverdata, string $url)
1201         {
1202                 $doc = new DOMDocument();
1203                 @$doc->loadHTML($curlResult->getBody());
1204                 $xpath = new DOMXPath($doc);
1205
1206                 $title = trim(XML::getFirstNodeValue($xpath, '//head/title/text()'));
1207                 if (!empty($title)) {
1208                         $serverdata['site_name'] = $title;
1209                 }
1210
1211                 $list = $xpath->query('//meta[@name]');
1212
1213                 foreach ($list as $node) {
1214                         $attr = [];
1215                         if ($node->attributes->length) {
1216                                 foreach ($node->attributes as $attribute) {
1217                                         $value = trim($attribute->value);
1218                                         if (empty($value)) {
1219                                                 continue;
1220                                         }
1221
1222                                         $attr[$attribute->name] = $value;
1223                                 }
1224
1225                                 if (empty($attr['name']) || empty($attr['content'])) {
1226                                         continue;
1227                                 }
1228                         }
1229
1230                         if ($attr['name'] == 'description') {
1231                                 $serverdata['info'] = $attr['content'];
1232                         }
1233
1234                         if ($attr['name'] == 'application-name') {
1235                                 $serverdata['platform'] = strtolower($attr['content']);
1236                                 if (in_array($attr['content'], ['Misskey', 'Write.as'])) {
1237                                         $serverdata['network'] = Protocol::ACTIVITYPUB;
1238                                 }
1239                         }
1240                         if (($attr['name'] == 'generator') && (empty($serverdata['platform']) || (substr(strtolower($attr['content']), 0, 9) == 'wordpress'))) {
1241                                 $serverdata['platform'] = strtolower($attr['content']);
1242                                 $version_part = explode(' ', $attr['content']);
1243
1244                                 if (count($version_part) == 2) {
1245                                         if (in_array($version_part[0], ['WordPress'])) {
1246                                                 $serverdata['platform'] = strtolower($version_part[0]);
1247                                                 $serverdata['version'] = $version_part[1];
1248
1249                                                 // We still do need a reliable test if some AP plugin is activated
1250                                                 if (DBA::exists('apcontact', ['baseurl' => $url])) {
1251                                                         $serverdata['network'] = Protocol::ACTIVITYPUB;
1252                                                 } else {
1253                                                         $serverdata['network'] = Protocol::FEED;
1254                                                 }
1255                                         }
1256                                         if (in_array($version_part[0], ['Friendika', 'Friendica'])) {
1257                                                 $serverdata['platform'] = strtolower($version_part[0]);
1258                                                 $serverdata['version'] = $version_part[1];
1259                                                 $serverdata['network'] = Protocol::DFRN;
1260                                         }
1261                                 }
1262                         }
1263                 }
1264
1265                 $list = $xpath->query('//meta[@property]');
1266
1267                 foreach ($list as $node) {
1268                         $attr = [];
1269                         if ($node->attributes->length) {
1270                                 foreach ($node->attributes as $attribute) {
1271                                         $value = trim($attribute->value);
1272                                         if (empty($value)) {
1273                                                 continue;
1274                                         }
1275
1276                                         $attr[$attribute->name] = $value;
1277                                 }
1278
1279                                 if (empty($attr['property']) || empty($attr['content'])) {
1280                                         continue;
1281                                 }
1282                         }
1283
1284                         if ($attr['property'] == 'og:site_name') {
1285                                 $serverdata['site_name'] = $attr['content'];
1286                         }
1287
1288                         if ($attr['property'] == 'og:description') {
1289                                 $serverdata['info'] = $attr['content'];
1290                         }
1291
1292                         if ($attr['property'] == 'og:platform') {
1293                                 $serverdata['platform'] = strtolower($attr['content']);
1294
1295                                 if (in_array($attr['content'], ['PeerTube'])) {
1296                                         $serverdata['network'] = Protocol::ACTIVITYPUB;
1297                                 }
1298                         }
1299
1300                         if ($attr['property'] == 'generator') {
1301                                 $serverdata['platform'] = strtolower($attr['content']);
1302
1303                                 if (in_array($attr['content'], ['hubzilla'])) {
1304                                         // We later check which compatible protocol modules are loaded.
1305                                         $serverdata['network'] = Protocol::ZOT;
1306                                 }
1307                         }
1308                 }
1309
1310                 return $serverdata;
1311         }
1312
1313         /**
1314          * Analyses the header data of a given server for hints about type and system of that server
1315          *
1316          * @param object $curlResult result of curl execution
1317          * @param array  $serverdata array with server data
1318          *
1319          * @return array server data
1320          */
1321         private static function analyseRootHeader($curlResult, array $serverdata)
1322         {
1323                 if ($curlResult->getHeader('server') == 'Mastodon') {
1324                         $serverdata['platform'] = 'mastodon';
1325                         $serverdata['network'] = $network = Protocol::ACTIVITYPUB;
1326                 } elseif ($curlResult->inHeader('x-diaspora-version')) {
1327                         $serverdata['platform'] = 'diaspora';
1328                         $serverdata['network'] = $network = Protocol::DIASPORA;
1329                         $serverdata['version'] = $curlResult->getHeader('x-diaspora-version');
1330                 } elseif ($curlResult->inHeader('x-friendica-version')) {
1331                         $serverdata['platform'] = 'friendica';
1332                         $serverdata['network'] = $network = Protocol::DFRN;
1333                         $serverdata['version'] = $curlResult->getHeader('x-friendica-version');
1334                 }
1335                 return $serverdata;
1336         }
1337
1338         /**
1339          * Test if the body contains valid content
1340          *
1341          * @param string $body
1342          * @return boolean
1343          */
1344         private static function invalidBody(string $body)
1345         {
1346                 // Currently we only test for a HTML element.
1347                 // Possibly we enhance this in the future.
1348                 return !strpos($body, '>');
1349         }
1350
1351         /**
1352          * Update the user directory of a given gserver record
1353          *
1354          * @param array $gserver gserver record
1355          */
1356         public static function updateDirectory(array $gserver)
1357         {
1358                 /// @todo Add Mastodon API directory
1359
1360                 if (!empty($gserver['poco'])) {
1361                         PortableContact::discoverSingleServer($gserver['id']);
1362                 }
1363         }
1364
1365         /**
1366          * Update GServer entries
1367          */
1368         public static function discover()
1369         {
1370                 // Update the server list
1371                 self::discoverFederation();
1372
1373                 $no_of_queries = 5;
1374
1375                 $requery_days = intval(DI::config()->get('system', 'poco_requery_days'));
1376
1377                 if ($requery_days == 0) {
1378                         $requery_days = 7;
1379                 }
1380
1381                 $last_update = date('c', time() - (60 * 60 * 24 * $requery_days));
1382
1383                 $gservers = DBA::p("SELECT `id`, `url`, `nurl`, `network`, `poco`
1384                         FROM `gserver`
1385                         WHERE `last_contact` >= `last_failure`
1386                         AND `poco` != ''
1387                         AND `last_poco_query` < ?
1388                         ORDER BY RAND()", $last_update
1389                 );
1390
1391                 while ($gserver = DBA::fetch($gservers)) {
1392                         if (!GServer::check($gserver['url'], $gserver['network'])) {
1393                                 // The server is not reachable? Okay, then we will try it later
1394                                 $fields = ['last_poco_query' => DateTimeFormat::utcNow()];
1395                                 DBA::update('gserver', $fields, ['nurl' => $gserver['nurl']]);
1396                                 continue;
1397                         }
1398
1399                         Logger::info('Update directory', ['server' => $gserver['url'], 'id' => $gserver['id']]);
1400                         Worker::add(PRIORITY_LOW, 'UpdateServerDirectory', $gserver);
1401
1402                         if (--$no_of_queries == 0) {
1403                                 break;
1404                         }
1405                 }
1406
1407                 DBA::close($gservers);
1408         }
1409
1410         /**
1411          * Discover federated servers
1412          */
1413         private static function discoverFederation()
1414         {
1415                 $last = DI::config()->get('poco', 'last_federation_discovery');
1416
1417                 if ($last) {
1418                         $next = $last + (24 * 60 * 60);
1419
1420                         if ($next > time()) {
1421                                 return;
1422                         }
1423                 }
1424
1425                 // Discover federated servers
1426                 $curlResult = Network::fetchUrl("http://the-federation.info/pods.json");
1427
1428                 if (!empty($curlResult)) {
1429                         $servers = json_decode($curlResult, true);
1430
1431                         if (!empty($servers['pods'])) {
1432                                 foreach ($servers['pods'] as $server) {
1433                                         Worker::add(PRIORITY_LOW, 'UpdateGServer', 'https://' . $server['host']);
1434                                 }
1435                         }
1436                 }
1437
1438                 // Disvover Mastodon servers
1439                 $accesstoken = DI::config()->get('system', 'instances_social_key');
1440
1441                 if (!empty($accesstoken)) {
1442                         $api = 'https://instances.social/api/1.0/instances/list?count=0';
1443                         $header = ['Authorization: Bearer '.$accesstoken];
1444                         $curlResult = Network::curl($api, false, ['headers' => $header]);
1445
1446                         if ($curlResult->isSuccess()) {
1447                                 $servers = json_decode($curlResult->getBody(), true);
1448
1449                                 foreach ($servers['instances'] as $server) {
1450                                         $url = (is_null($server['https_score']) ? 'http' : 'https') . '://' . $server['name'];
1451                                         Worker::add(PRIORITY_LOW, 'UpdateGServer', $url);
1452                                 }
1453                         }
1454                 }
1455
1456                 DI::config()->set('poco', 'last_federation_discovery', time());
1457         }
1458 }