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          * @return boolean "true" is the post is wanted by the system
  61          */
  62         public static function isSolicitedPost(array $tags, string $body, int $authorid, string $url, string $network = '', int $causerid = 0): bool
  63         {
  64                 $config = DI::config();
  65
  66                 $scope = $config->get('system', 'relay_scope');
  67
  68                 if ($scope == self::SCOPE_NONE) {
  69                         Logger::info('Server does not accept relay posts - rejected', ['network' => $network, 'url' => $url]);
  70                         return false;
  71                 }
  72
  73                 if (Contact::isBlocked($authorid)) {
  74                         Logger::info('Author is blocked - rejected', ['author' => $authorid, 'network' => $network, 'url' => $url]);
  75                         return false;
  76                 }
  77
  78                 if (Contact::isHidden($authorid)) {
  79                         Logger::info('Author is hidden - rejected', ['author' => $authorid, 'network' => $network, 'url' => $url]);
  80                         return false;
  81                 }
  82
  83                 if (!empty($causerid)) {
  84                         $contact = Contact::getById($causerid, ['url']);
  85                         $causer = $contact['url'] ?? '';
  86                 } else {
  87                         $causer = '';
  88                 }
  89
  90                 $body = ActivityPub\Processor::normalizeMentionLinks($body);
  91
  92                 $denyTags = [];
  93
  94                 if ($scope == self::SCOPE_TAGS) {
  95                         $tagList = self::getSubscribedTags();
  96                 } else {
  97                         $tagList  = [];
  98                 }
  99
 100                 $deny_tags = $config->get('system', 'relay_deny_tags');
 101                 $tagitems = explode(',', mb_strtolower($deny_tags));
 102                 foreach ($tagitems as $tag) {
 103                         $tag = trim($tag, '# ');
 104                         $denyTags[] = $tag;
 105                 }
 106
 107                 if (!empty($tagList) || !empty($denyTags)) {
 108                         $content = mb_strtolower(BBCode::toPlaintext($body, false));
 109
 110                         foreach ($tags as $tag) {
 111                                 $tag = mb_strtolower($tag);
 112                                 if (in_array($tag, $denyTags)) {
 113                                         Logger::info('Unwanted hashtag found - rejected', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 114                                         return false;
 115                                 }
 116
 117                                 if (in_array($tag, $tagList)) {
 118                                         Logger::info('Subscribed hashtag found - accepted', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 119                                         return true;
 120                                 }
 121
 122                                 // We check with "strpos" for performance issues. Only when this is true, the regular expression check is used
 123                                 // RegExp is taken from here: https://medium.com/@shiba1014/regex-word-boundaries-with-unicode-207794f6e7ed
 124                                 if ((strpos($content, $tag) !== false) && preg_match('/(?<=[\s,.:;"\']|^)' . preg_quote($tag, '/') . '(?=[\s,.:;"\']|$)/', $content)) {
 125                                         Logger::info('Subscribed hashtag found in content - accepted', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 126                                         return true;
 127                                 }
 128                         }
 129                 }
 130
 131                 if (!self::isWantedLanguage($body, 0, $authorid)) {
 132                         Logger::info('Unwanted or Undetected language found - rejected', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 133                         return false;
 134                 }
 135
 136                 if ($scope == self::SCOPE_ALL) {
 137                         Logger::info('Server accept all posts - accepted', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 138                         return true;
 139                 }
 140
 141                 Logger::info('No matching hashtags found - rejected', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 142                 return false;
 143         }
 144
 145         /**
 146          * Get a list of subscribed tags by both the users and the tags that are defined by the admin
 147          *
 148          * @return array
 149          */
 150         public static function getSubscribedTags(): array
 151         {
 152                 $systemTags  = [];
 153                 $server_tags = DI::config()->get('system', 'relay_server_tags');
 154
 155                 foreach (explode(',', mb_strtolower($server_tags)) as $tag) {
 156                         $systemTags[] = trim($tag, '# ');
 157                 }
 158
 159                 if (DI::config()->get('system', 'relay_user_tags')) {
 160                         $userTags = Search::getUserTags();
 161                 } else {
 162                         $userTags = [];
 163                 }
 164
 165                 return array_unique(array_merge($systemTags, $userTags));
 166         }
 167
 168         /**
 169          * Detect the language of a post and decide if the post should be accepted
 170          *
 171          * @param string $body
 172          * @param int    $uri_id
 173          * @param int    $author_id
 174          * @return boolean
 175          */
 176         public static function isWantedLanguage(string $body, int $uri_id = 0, int $author_id = 0)
 177         {
 178                 if (empty($body) || Smilies::isEmojiPost($body)) {
 179                         Logger::debug('Empty body or only emojis', ['body' => $body]);
 180                         return true;
 181                 }
 182
 183                 $languages = [];
 184                 foreach (Item::getLanguageArray($body, 10, $uri_id, $author_id) as $language => $reliability) {
 185                         if ($reliability > 0) {
 186                                 $languages[] = $language;
 187                         }
 188                 }
 189
 190                 if (!empty($languages)) {
 191                         $cachekey = 'relay:isWantedLanguage';
 192                         $user_languages = DI::cache()->get($cachekey);
 193                         if (is_null($user_languages)) {
 194                                 $user_languages = User::getLanguages();
 195                                 DI::cache()->set($cachekey, $user_languages, Duration::HALF_HOUR);
 196                         }
 197
 198                         foreach ($languages as $language) {
 199                                 if (in_array($language, $user_languages)) {
 200                                         Logger::debug('Wanted language found', ['language' => $language, 'languages' => $languages, 'userlang' => $user_languages, 'body' => $body]);
 201                                         return true;
 202                                 }
 203                         }
 204                         Logger::debug('No wanted language found', ['languages' => $languages, 'userlang' => $user_languages, 'body' => $body]);
 205                         return false;
 206                 } elseif (DI::config()->get('system', 'relay_deny_undetected_language')) {
 207                         Logger::info('Undetected language found', ['body' => $body]);
 208                         return false;
 209                 }
 210
 211                 return true;
 212         }
 213
 214         /**
 215          * Update or insert a relay contact
 216          *
 217          * @param array $gserver Global server record
 218          * @param array $fields  Optional network specific fields
 219          * @return void
 220          * @throws \Exception
 221          */
 222         public static function updateContact(array $gserver, array $fields = [])
 223         {
 224                 if (in_array($gserver['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
 225                         $system = APContact::getByURL($gserver['url'] . '/friendica');
 226                         if (!empty($system['sharedinbox'])) {
 227                                 Logger::info('Successfully probed for relay contact', ['server' => $gserver['url']]);
 228                                 $id = Contact::updateFromProbeByURL($system['url']);
 229                                 Logger::info('Updated relay contact', ['server' => $gserver['url'], 'id' => $id]);
 230                                 return;
 231                         }
 232                 }
 233
 234                 $condition = ['uid' => 0, 'gsid' => $gserver['id'], 'contact-type' => Contact::TYPE_RELAY];
 235                 $old = DBA::selectFirst('contact', [], $condition);
 236                 if (!DBA::isResult($old)) {
 237                         $condition = ['uid' => 0, 'nurl' => Strings::normaliseLink($gserver['url'])];
 238                         $old = DBA::selectFirst('contact', [], $condition);
 239                         if (DBA::isResult($old)) {
 240                                 $fields['gsid'] = $gserver['id'];
 241                                 $fields['contact-type'] = Contact::TYPE_RELAY;
 242                                 Logger::info('Assigning missing data for relay contact', ['server' => $gserver['url'], 'id' => $old['id']]);
 243                         }
 244                 } elseif (empty($fields)) {
 245                         Logger::info('No content to update, quitting', ['server' => $gserver['url']]);
 246                         return;
 247                 }
 248
 249                 if (DBA::isResult($old)) {
 250                         $fields['updated'] = DateTimeFormat::utcNow();
 251
 252                         Logger::info('Update relay contact', ['server' => $gserver['url'], 'id' => $old['id'], 'fields' => $fields]);
 253                         Contact::update($fields, ['id' => $old['id']], $old);
 254                 } else {
 255                         $default = ['created' => DateTimeFormat::utcNow(),
 256                                 'name' => 'relay', 'nick' => 'relay', 'url' => $gserver['url'],
 257                                 'nurl' => Strings::normaliseLink($gserver['url']),
 258                                 'network' => Protocol::DIASPORA, 'uid' => 0,
 259                                 'batch' => $gserver['url'] . '/receive/public',
 260                                 'rel' => Contact::FOLLOWER, 'blocked' => false,
 261                                 'pending' => false, 'writable' => true,
 262                                 'gsid' => $gserver['id'],
 263                                 'baseurl' => $gserver['url'], 'contact-type' => Contact::TYPE_RELAY];
 264
 265                         $fields = array_merge($default, $fields);
 266
 267                         Logger::info('Create relay contact', ['server' => $gserver['url'], 'fields' => $fields]);
 268                         Contact::insert($fields);
 269                 }
 270         }
 271
 272         /**
 273          * Mark the relay contact of the given contact for archival
 274          * This is called whenever there is a communication issue with the server.
 275          * It avoids sending stuff to servers who don't exist anymore.
 276          * The relay contact is a technical contact entry that exists once per server.
 277          *
 278          * @param array $contact of the relay contact
 279          * @return void
 280          */
 281         public static function markForArchival(array $contact)
 282         {
 283                 if (!empty($contact['contact-type']) && ($contact['contact-type'] == Contact::TYPE_RELAY)) {
 284                         // This is already the relay contact, we don't need to fetch it
 285                         $relay_contact = $contact;
 286                 } elseif (empty($contact['baseurl'])) {
 287                         if (!empty($contact['batch'])) {
 288                                 $condition = ['uid' => 0, 'network' => Protocol::FEDERATED, 'batch' => $contact['batch'], 'contact-type' => Contact::TYPE_RELAY];
 289                                 $relay_contact = DBA::selectFirst('contact', [], $condition);
 290                         } else {
 291                                 return;
 292                         }
 293                 } else {
 294                         $gserver = ['id' => $contact['gsid'] ?: GServer::getID($contact['baseurl'], true),
 295                                 'url' => $contact['baseurl'], 'network' => $contact['network']];
 296                         $relay_contact = self::getContact($gserver, []);
 297                 }
 298
 299                 if (!empty($relay_contact)) {
 300                         Logger::info('Relay contact will be marked for archival', ['id' => $relay_contact['id'], 'url' => $relay_contact['url']]);
 301                         Contact::markForArchival($relay_contact);
 302                 }
 303         }
 304
 305         /**
 306          * Return a list of servers that we serve via the direct relay
 307          *
 308          * @param integer $item_id  id of the item that is sent
 309          * @param array   $contacts Previously fetched contacts
 310          * @param array   $networks Networks of the relay servers
 311          * @return array of relay servers
 312          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 313          */
 314         public static function getDirectRelayList(int $item_id): array
 315         {
 316                 $serverlist = [];
 317
 318                 if (!DI::config()->get('system', 'relay_directly', false)) {
 319                         return [];
 320                 }
 321
 322                 // We distribute our stuff based on the parent to ensure that the thread will be complete
 323                 $parent = Post::selectFirst(['uri-id'], ['id' => $item_id]);
 324                 if (!DBA::isResult($parent)) {
 325                         return [];
 326                 }
 327
 328                 // Servers that want to get all content
 329                 $servers = DBA::select('gserver', ['id', 'url', 'network'], ['relay-subscribe' => true, 'relay-scope' => 'all']);
 330                 while ($server = DBA::fetch($servers)) {
 331                         $serverlist[$server['id']] = $server;
 332                 }
 333                 DBA::close($servers);
 334
 335                 // All tags of the current post
 336                 $tags = DBA::select('tag-view', ['name'], ['uri-id' => $parent['uri-id'], 'type' => Tag::HASHTAG]);
 337                 $taglist = [];
 338                 while ($tag = DBA::fetch($tags)) {
 339                         $taglist[] = $tag['name'];
 340                 }
 341                 DBA::close($tags);
 342
 343                 // All servers who wants content with this tag
 344                 $tagserverlist = [];
 345                 if (!empty($taglist)) {
 346                         $tagserver = DBA::select('gserver-tag', ['gserver-id'], ['tag' => $taglist]);
 347                         while ($server = DBA::fetch($tagserver)) {
 348                                 $tagserverlist[] = $server['gserver-id'];
 349                         }
 350                         DBA::close($tagserver);
 351                 }
 352
 353                 // All addresses with the given id
 354                 if (!empty($tagserverlist)) {
 355                         $servers = DBA::select('gserver', ['id', 'url', 'network'], ['relay-subscribe' => true, 'relay-scope' => 'tags', 'id' => $tagserverlist]);
 356                         while ($server = DBA::fetch($servers)) {
 357                                 $serverlist[$server['id']] = $server;
 358                         }
 359                         DBA::close($servers);
 360                 }
 361
 362                 $contacts = [];
 363
 364                 // Now we are collecting all relay contacts
 365                 foreach ($serverlist as $gserver) {
 366                         // We don't send messages to ourselves
 367                         if (Strings::compareLink($gserver['url'], DI::baseUrl())) {
 368                                 continue;
 369                         }
 370                         $contact = self::getContact($gserver);
 371                         if (empty($contact)) {
 372                                 continue;
 373                         }
 374                 }
 375
 376                 return $contacts;
 377         }
 378
 379         /**
 380          * Return a list of relay servers
 381          *
 382          * @param array $fields Field list
 383          * @return array List of relay servers
 384          * @throws Exception
 385          */
 386         public static function getList(array $fields = []): array
 387         {
 388                 return DBA::selectToArray('apcontact', $fields,
 389                         ["`type` IN (?, ?) AND `url` IN (SELECT `url` FROM `contact` WHERE `uid` = ? AND `rel` = ?)", 'Application', 'Service', 0, Contact::FRIEND]);
 390         }
 391
 392         /**
 393          * Return a contact for a given server address or creates a dummy entry
 394          *
 395          * @param array $gserver Global server record
 396          * @param array $fields  Fieldlist
 397          * @return array|bool Array with the contact or false on error
 398          * @throws \Exception
 399          */
 400         private static function getContact(array $gserver, array $fields = ['batch', 'id', 'url', 'name', 'network', 'protocol', 'archive', 'blocked'])
 401         {
 402                 // Fetch the relay contact
 403                 $condition = ['uid' => 0, 'gsid' => $gserver['id'], 'contact-type' => Contact::TYPE_RELAY];
 404                 $contact = DBA::selectFirst('contact', $fields, $condition);
 405                 if (DBA::isResult($contact)) {
 406                         if ($contact['archive'] || $contact['blocked']) {
 407                                 return false;
 408                         }
 409                         return $contact;
 410                 } else {
 411                         self::updateContact($gserver);
 412
 413                         $contact = DBA::selectFirst('contact', $fields, $condition);
 414                         if (DBA::isResult($contact)) {
 415                                 return $contact;
 416                         }
 417                 }
 418
 419                 // It should never happen that we arrive here
 420                 return [];
 421         }
 422
 423         /**
 424          * Resubscribe to all relay servers
 425          *
 426          * @return void
 427          */
 428         public static function reSubscribe()
 429         {
 430                 foreach (self::getList() as $server) {
 431                         $success = ActivityPub\Transmitter::sendRelayFollow($server['url']);
 432                         Logger::debug('Resubscribed', ['profile' => $server['url'], 'success' => $success]);
 433                 }
 434         }
 435 }