src/Protocol/Relay.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2023, the Friendica project
   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\Protocol;
  23
  24 use Friendica\Content\Smilies;
  25 use Friendica\Content\Text\BBCode;
  26 use Friendica\Core\Cache\Enum\Duration;
  27 use Friendica\Core\Logger;
  28 use Friendica\Core\Protocol;
  29 use Friendica\Database\DBA;
  30 use Friendica\DI;
  31 use Friendica\Model\APContact;
  32 use Friendica\Model\Contact;
  33 use Friendica\Model\GServer;
  34 use Friendica\Model\Item;
  35 use Friendica\Model\Post;
  36 use Friendica\Model\Search;
  37 use Friendica\Model\Tag;
  38 use Friendica\Model\User;
  39 use Friendica\Util\DateTimeFormat;
  40 use Friendica\Util\Strings;
  41
  42 /**
  43  * Base class for relay handling
  44  * @see https://github.com/jaywink/social-relay
  45  * @see https://wiki.diasporafoundation.org/Relay_servers_for_public_posts
  46  */
  47 class Relay
  48 {
  49         const SCOPE_NONE = '';
  50         const SCOPE_ALL = 'all';
  51         const SCOPE_TAGS = 'tags';
  52
  53         /**
  54          * Check if a post is wanted
  55          *
  56          * @param array  $tags
  57          * @param string $body
  58          * @param int    $authorid
  59          * @param string $url
  60          * @param string $network
  61          * @param int    $causerid
  62          * @param array  $languages
  63          * @return boolean "true" is the post is wanted by the system
  64          */
  65         public static function isSolicitedPost(array $tags, string $body, int $authorid, string $url, string $network = '', int $causerid = 0, array $languages = []): bool
  66         {
  67                 $config = DI::config();
  68
  69                 $scope = $config->get('system', 'relay_scope');
  70
  71                 if ($scope == self::SCOPE_NONE) {
  72                         Logger::info('Server does not accept relay posts - rejected', ['network' => $network, 'url' => $url]);
  73                         return false;
  74                 }
  75
  76                 if (Contact::isBlocked($authorid)) {
  77                         Logger::info('Author is blocked - rejected', ['author' => $authorid, 'network' => $network, 'url' => $url]);
  78                         return false;
  79                 }
  80
  81                 if (Contact::isHidden($authorid)) {
  82                         Logger::info('Author is hidden - rejected', ['author' => $authorid, 'network' => $network, 'url' => $url]);
  83                         return false;
  84                 }
  85
  86                 if (!empty($causerid)) {
  87                         $contact = Contact::getById($causerid, ['url']);
  88                         $causer = $contact['url'] ?? '';
  89                 } else {
  90                         $causer = '';
  91                 }
  92
  93                 $body = ActivityPub\Processor::normalizeMentionLinks($body);
  94
  95                 $denyTags = [];
  96
  97                 if ($scope == self::SCOPE_TAGS) {
  98                         $tagList = self::getSubscribedTags();
  99                 } else {
 100                         $tagList  = [];
 101                 }
 102
 103                 $deny_tags = $config->get('system', 'relay_deny_tags');
 104                 $tagitems = explode(',', mb_strtolower($deny_tags));
 105                 foreach ($tagitems as $tag) {
 106                         $tag = trim($tag, '# ');
 107                         $denyTags[] = $tag;
 108                 }
 109
 110                 if (!empty($tagList) || !empty($denyTags)) {
 111                         $content = mb_strtolower(BBCode::toPlaintext($body, false));
 112
 113                         foreach ($tags as $tag) {
 114                                 $tag = mb_strtolower($tag);
 115                                 if (in_array($tag, $denyTags)) {
 116                                         Logger::info('Unwanted hashtag found - rejected', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 117                                         return false;
 118                                 }
 119
 120                                 if (in_array($tag, $tagList)) {
 121                                         Logger::info('Subscribed hashtag found - accepted', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 122                                         return true;
 123                                 }
 124
 125                                 // We check with "strpos" for performance issues. Only when this is true, the regular expression check is used
 126                                 // RegExp is taken from here: https://medium.com/@shiba1014/regex-word-boundaries-with-unicode-207794f6e7ed
 127                                 if ((strpos($content, $tag) !== false) && preg_match('/(?<=[\s,.:;"\']|^)' . preg_quote($tag, '/') . '(?=[\s,.:;"\']|$)/', $content)) {
 128                                         Logger::info('Subscribed hashtag found in content - accepted', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 129                                         return true;
 130                                 }
 131                         }
 132                 }
 133
 134                 if (!self::isWantedLanguage($body, 0, $authorid, $languages)) {
 135                         Logger::info('Unwanted or Undetected language found - rejected', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 136                         return false;
 137                 }
 138
 139                 if ($scope == self::SCOPE_ALL) {
 140                         Logger::info('Server accept all posts - accepted', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 141                         return true;
 142                 }
 143
 144                 Logger::info('No matching hashtags found - rejected', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 145                 return false;
 146         }
 147
 148         /**
 149          * Get a list of subscribed tags by both the users and the tags that are defined by the admin
 150          *
 151          * @return array
 152          */
 153         public static function getSubscribedTags(): array
 154         {
 155                 $systemTags  = [];
 156                 $server_tags = DI::config()->get('system', 'relay_server_tags');
 157
 158                 foreach (explode(',', mb_strtolower($server_tags)) as $tag) {
 159                         $systemTags[] = trim($tag, '# ');
 160                 }
 161
 162                 if (DI::config()->get('system', 'relay_user_tags')) {
 163                         $userTags = Search::getUserTags();
 164                 } else {
 165                         $userTags = [];
 166                 }
 167
 168                 return array_unique(array_merge($systemTags, $userTags));
 169         }
 170
 171         /**
 172          * Detect the language of a post and decide if the post should be accepted
 173          *
 174          * @param string $body
 175          * @param int    $uri_id
 176          * @param int    $author_id
 177          * @param array  $languages
 178          * @return boolean
 179          */
 180         public static function isWantedLanguage(string $body, int $uri_id = 0, int $author_id = 0, array $languages = [])
 181         {
 182                 if (empty($languages) && (empty($body) || Smilies::isEmojiPost($body))) {
 183                         Logger::debug('Empty body or only emojis', ['body' => $body]);
 184                         return true;
 185                 }
 186
 187                 $detected = [];
 188                 $quality  = DI::config()->get('system', 'relay_language_quality');
 189                 foreach (Item::getLanguageArray($body, DI::config()->get('system', 'relay_languages'), $uri_id, $author_id) as $language => $reliability) {
 190                         if (($reliability >= $quality) && ($quality > 0)) {
 191                                 $detected[] = $language;
 192                         }
 193                 }
 194
 195                 if (!empty($languages) || !empty($detected)) {
 196                         $cachekey = 'relay:isWantedLanguage';
 197                         $user_languages = DI::cache()->get($cachekey);
 198                         if (is_null($user_languages)) {
 199                                 $user_languages = User::getLanguages();
 200                                 DI::cache()->set($cachekey, $user_languages);
 201                         }
 202
 203                         foreach ($detected as $language) {
 204                                 if (in_array($language, $user_languages)) {
 205                                         Logger::debug('Wanted language found in detected languages', ['language' => $language, 'detected' => $detected, 'userlang' => $user_languages, 'body' => $body]);
 206                                         return true;
 207                                 }
 208                         }
 209                         foreach ($languages as $language) {
 210                                 if (in_array($language, $user_languages)) {
 211                                         Logger::debug('Wanted language found in defined languages', ['language' => $language, 'languages' => $languages, 'detected' => $detected, 'userlang' => $user_languages, 'body' => $body]);
 212                                         return true;
 213                                 }
 214                         }
 215                         Logger::debug('No wanted language found', ['languages' => $languages, 'detected' => $detected, 'userlang' => $user_languages, 'body' => $body]);
 216                         return false;
 217                 } elseif (DI::config()->get('system', 'relay_deny_undetected_language')) {
 218                         Logger::info('Undetected language found', ['body' => $body]);
 219                         return false;
 220                 }
 221
 222                 return true;
 223         }
 224
 225         /**
 226          * Update or insert a relay contact
 227          *
 228          * @param array $gserver Global server record
 229          * @param array $fields  Optional network specific fields
 230          * @return void
 231          * @throws \Exception
 232          */
 233         public static function updateContact(array $gserver, array $fields = [])
 234         {
 235                 if (in_array($gserver['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
 236                         $system = APContact::getByURL($gserver['url'] . '/friendica');
 237                         if (!empty($system['sharedinbox'])) {
 238                                 Logger::info('Successfully probed for relay contact', ['server' => $gserver['url']]);
 239                                 $id = Contact::updateFromProbeByURL($system['url']);
 240                                 Logger::info('Updated relay contact', ['server' => $gserver['url'], 'id' => $id]);
 241                                 return;
 242                         }
 243                 }
 244
 245                 $condition = ['uid' => 0, 'gsid' => $gserver['id'], 'contact-type' => Contact::TYPE_RELAY];
 246                 $old = DBA::selectFirst('contact', [], $condition);
 247                 if (!DBA::isResult($old)) {
 248                         $condition = ['uid' => 0, 'nurl' => Strings::normaliseLink($gserver['url'])];
 249                         $old = DBA::selectFirst('contact', [], $condition);
 250                         if (DBA::isResult($old)) {
 251                                 $fields['gsid'] = $gserver['id'];
 252                                 $fields['contact-type'] = Contact::TYPE_RELAY;
 253                                 Logger::info('Assigning missing data for relay contact', ['server' => $gserver['url'], 'id' => $old['id']]);
 254                         }
 255                 } elseif (empty($fields)) {
 256                         Logger::info('No content to update, quitting', ['server' => $gserver['url']]);
 257                         return;
 258                 }
 259
 260                 if (DBA::isResult($old)) {
 261                         $fields['updated'] = DateTimeFormat::utcNow();
 262
 263                         Logger::info('Update relay contact', ['server' => $gserver['url'], 'id' => $old['id'], 'fields' => $fields]);
 264                         Contact::update($fields, ['id' => $old['id']], $old);
 265                 } else {
 266                         $default = ['created' => DateTimeFormat::utcNow(),
 267                                 'name' => 'relay', 'nick' => 'relay', 'url' => $gserver['url'],
 268                                 'nurl' => Strings::normaliseLink($gserver['url']),
 269                                 'network' => Protocol::DIASPORA, 'uid' => 0,
 270                                 'batch' => $gserver['url'] . '/receive/public',
 271                                 'rel' => Contact::FOLLOWER, 'blocked' => false,
 272                                 'pending' => false, 'writable' => true,
 273                                 'gsid' => $gserver['id'],
 274                                 'baseurl' => $gserver['url'], 'contact-type' => Contact::TYPE_RELAY];
 275
 276                         $fields = array_merge($default, $fields);
 277
 278                         Logger::info('Create relay contact', ['server' => $gserver['url'], 'fields' => $fields]);
 279                         Contact::insert($fields);
 280                 }
 281         }
 282
 283         /**
 284          * Mark the relay contact of the given contact for archival
 285          * This is called whenever there is a communication issue with the server.
 286          * It avoids sending stuff to servers who don't exist anymore.
 287          * The relay contact is a technical contact entry that exists once per server.
 288          *
 289          * @param array $contact of the relay contact
 290          * @return void
 291          */
 292         public static function markForArchival(array $contact)
 293         {
 294                 if (!empty($contact['contact-type']) && ($contact['contact-type'] == Contact::TYPE_RELAY)) {
 295                         // This is already the relay contact, we don't need to fetch it
 296                         $relay_contact = $contact;
 297                 } elseif (empty($contact['baseurl'])) {
 298                         if (!empty($contact['batch'])) {
 299                                 $condition = ['uid' => 0, 'network' => Protocol::FEDERATED, 'batch' => $contact['batch'], 'contact-type' => Contact::TYPE_RELAY];
 300                                 $relay_contact = DBA::selectFirst('contact', [], $condition);
 301                         } else {
 302                                 return;
 303                         }
 304                 } else {
 305                         $gserver = ['id' => $contact['gsid'] ?: GServer::getID($contact['baseurl'], true),
 306                                 'url' => $contact['baseurl'], 'network' => $contact['network']];
 307                         $relay_contact = self::getContact($gserver, []);
 308                 }
 309
 310                 if (!empty($relay_contact)) {
 311                         Logger::info('Relay contact will be marked for archival', ['id' => $relay_contact['id'], 'url' => $relay_contact['url']]);
 312                         Contact::markForArchival($relay_contact);
 313                 }
 314         }
 315
 316         /**
 317          * Return a list of servers that we serve via the direct relay
 318          *
 319          * @param integer $item_id  id of the item that is sent
 320          * @param array   $contacts Previously fetched contacts
 321          * @param array   $networks Networks of the relay servers
 322          * @return array of relay servers
 323          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 324          */
 325         public static function getDirectRelayList(int $item_id): array
 326         {
 327                 $serverlist = [];
 328
 329                 if (!DI::config()->get('system', 'relay_directly', false)) {
 330                         return [];
 331                 }
 332
 333                 // We distribute our stuff based on the parent to ensure that the thread will be complete
 334                 $parent = Post::selectFirst(['uri-id'], ['id' => $item_id]);
 335                 if (!DBA::isResult($parent)) {
 336                         return [];
 337                 }
 338
 339                 // Servers that want to get all content
 340                 $servers = DBA::select('gserver', ['id', 'url', 'network'], ['relay-subscribe' => true, 'relay-scope' => 'all']);
 341                 while ($server = DBA::fetch($servers)) {
 342                         $serverlist[$server['id']] = $server;
 343                 }
 344                 DBA::close($servers);
 345
 346                 // All tags of the current post
 347                 $tags = DBA::select('tag-view', ['name'], ['uri-id' => $parent['uri-id'], 'type' => Tag::HASHTAG]);
 348                 $taglist = [];
 349                 while ($tag = DBA::fetch($tags)) {
 350                         $taglist[] = $tag['name'];
 351                 }
 352                 DBA::close($tags);
 353
 354                 // All servers who wants content with this tag
 355                 $tagserverlist = [];
 356                 if (!empty($taglist)) {
 357                         $tagserver = DBA::select('gserver-tag', ['gserver-id'], ['tag' => $taglist]);
 358                         while ($server = DBA::fetch($tagserver)) {
 359                                 $tagserverlist[] = $server['gserver-id'];
 360                         }
 361                         DBA::close($tagserver);
 362                 }
 363
 364                 // All addresses with the given id
 365                 if (!empty($tagserverlist)) {
 366                         $servers = DBA::select('gserver', ['id', 'url', 'network'], ['relay-subscribe' => true, 'relay-scope' => 'tags', 'id' => $tagserverlist]);
 367                         while ($server = DBA::fetch($servers)) {
 368                                 $serverlist[$server['id']] = $server;
 369                         }
 370                         DBA::close($servers);
 371                 }
 372
 373                 $contacts = [];
 374
 375                 // Now we are collecting all relay contacts
 376                 foreach ($serverlist as $gserver) {
 377                         // We don't send messages to ourselves
 378                         if (Strings::compareLink($gserver['url'], DI::baseUrl())) {
 379                                 continue;
 380                         }
 381                         $contact = self::getContact($gserver);
 382                         if (empty($contact)) {
 383                                 continue;
 384                         }
 385                 }
 386
 387                 return $contacts;
 388         }
 389
 390         /**
 391          * Return a list of relay servers
 392          *
 393          * @param array $fields Field list
 394          * @return array List of relay servers
 395          * @throws Exception
 396          */
 397         public static function getList(array $fields = []): array
 398         {
 399                 return DBA::selectToArray('apcontact', $fields,
 400                         ["`type` IN (?, ?) AND `url` IN (SELECT `url` FROM `contact` WHERE `uid` = ? AND `rel` = ?)", 'Application', 'Service', 0, Contact::FRIEND]);
 401         }
 402
 403         /**
 404          * Return a contact for a given server address or creates a dummy entry
 405          *
 406          * @param array $gserver Global server record
 407          * @param array $fields  Fieldlist
 408          * @return array|bool Array with the contact or false on error
 409          * @throws \Exception
 410          */
 411         private static function getContact(array $gserver, array $fields = ['batch', 'id', 'url', 'name', 'network', 'protocol', 'archive', 'blocked'])
 412         {
 413                 // Fetch the relay contact
 414                 $condition = ['uid' => 0, 'gsid' => $gserver['id'], 'contact-type' => Contact::TYPE_RELAY];
 415                 $contact = DBA::selectFirst('contact', $fields, $condition);
 416                 if (DBA::isResult($contact)) {
 417                         if ($contact['archive'] || $contact['blocked']) {
 418                                 return false;
 419                         }
 420                         return $contact;
 421                 } else {
 422                         self::updateContact($gserver);
 423
 424                         $contact = DBA::selectFirst('contact', $fields, $condition);
 425                         if (DBA::isResult($contact)) {
 426                                 return $contact;
 427                         }
 428                 }
 429
 430                 // It should never happen that we arrive here
 431                 return [];
 432         }
 433
 434         /**
 435          * Resubscribe to all relay servers
 436          *
 437          * @return void
 438          */
 439         public static function reSubscribe()
 440         {
 441                 foreach (self::getList() as $server) {
 442                         $success = ActivityPub\Transmitter::sendRelayFollow($server['url']);
 443                         Logger::debug('Resubscribed', ['profile' => $server['url'], 'success' => $success]);
 444                 }
 445         }
 446 }