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\Logger;
  27 use Friendica\Core\Protocol;
  28 use Friendica\Database\DBA;
  29 use Friendica\DI;
  30 use Friendica\Model\APContact;
  31 use Friendica\Model\Contact;
  32 use Friendica\Model\GServer;
  33 use Friendica\Model\Item;
  34 use Friendica\Model\Post;
  35 use Friendica\Model\Search;
  36 use Friendica\Model\Tag;
  37 use Friendica\Util\DateTimeFormat;
  38 use Friendica\Util\Strings;
  39
  40 /**
  41  * Base class for relay handling
  42  * @see https://github.com/jaywink/social-relay
  43  * @see https://wiki.diasporafoundation.org/Relay_servers_for_public_posts
  44  */
  45 class Relay
  46 {
  47         const SCOPE_NONE = '';
  48         const SCOPE_ALL = 'all';
  49         const SCOPE_TAGS = 'tags';
  50
  51         /**
  52          * Check if a post is wanted
  53          *
  54          * @param array $tags
  55          * @param string $body
  56          * @param int $authorid
  57          * @param string $url
  58          * @return boolean "true" is the post is wanted by the system
  59          */
  60         public static function isSolicitedPost(array $tags, string $body, int $authorid, string $url, string $network = '', int $causerid = 0): bool
  61         {
  62                 $config = DI::config();
  63
  64                 $scope = $config->get('system', 'relay_scope');
  65
  66                 if ($scope == self::SCOPE_NONE) {
  67                         Logger::info('Server does not accept relay posts - rejected', ['network' => $network, 'url' => $url]);
  68                         return false;
  69                 }
  70
  71                 if (Contact::isBlocked($authorid)) {
  72                         Logger::info('Author is blocked - rejected', ['author' => $authorid, 'network' => $network, 'url' => $url]);
  73                         return false;
  74                 }
  75
  76                 if (Contact::isHidden($authorid)) {
  77                         Logger::info('Author is hidden - rejected', ['author' => $authorid, 'network' => $network, 'url' => $url]);
  78                         return false;
  79                 }
  80
  81                 if (!empty($causerid)) {
  82                         $contact = Contact::getById($causerid, ['url']);
  83                         $causer = $contact['url'] ?? '';
  84                 } else {
  85                         $causer = '';
  86                 }
  87
  88                 $body = ActivityPub\Processor::normalizeMentionLinks($body);
  89
  90                 $denyTags = [];
  91
  92                 if ($scope == self::SCOPE_TAGS) {
  93                         $tagList = self::getSubscribedTags();
  94                 } else {
  95                         $tagList  = [];
  96                 }
  97
  98                 $deny_tags = $config->get('system', 'relay_deny_tags');
  99                 $tagitems = explode(',', mb_strtolower($deny_tags));
 100                 foreach ($tagitems as $tag) {
 101                         $tag = trim($tag, '# ');
 102                         $denyTags[] = $tag;
 103                 }
 104
 105                 if (!empty($tagList) || !empty($denyTags)) {
 106                         $content = mb_strtolower(BBCode::toPlaintext($body, false));
 107
 108                         foreach ($tags as $tag) {
 109                                 $tag = mb_strtolower($tag);
 110                                 if (in_array($tag, $denyTags)) {
 111                                         Logger::info('Unwanted hashtag found - rejected', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 112                                         return false;
 113                                 }
 114
 115                                 if (in_array($tag, $tagList)) {
 116                                         Logger::info('Subscribed hashtag found - accepted', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 117                                         return true;
 118                                 }
 119
 120                                 // We check with "strpos" for performance issues. Only when this is true, the regular expression check is used
 121                                 // RegExp is taken from here: https://medium.com/@shiba1014/regex-word-boundaries-with-unicode-207794f6e7ed
 122                                 if ((strpos($content, $tag) !== false) && preg_match('/(?<=[\s,.:;"\']|^)' . preg_quote($tag, '/') . '(?=[\s,.:;"\']|$)/', $content)) {
 123                                         Logger::info('Subscribed hashtag found in content - accepted', ['hashtag' => $tag, 'network' => $network, 'url' => $url, 'causer' => $causer]);
 124                                         return true;
 125                                 }
 126                         }
 127                 }
 128
 129                 if (!self::isWantedLanguage($body, 0, $authorid)) {
 130                         Logger::info('Unwanted or Undetected language found - rejected', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 131                         return false;
 132                 }
 133
 134                 if ($scope == self::SCOPE_ALL) {
 135                         Logger::info('Server accept all posts - accepted', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 136                         return true;
 137                 }
 138
 139                 Logger::info('No matching hashtags found - rejected', ['network' => $network, 'url' => $url, 'causer' => $causer, 'tags' => $tags]);
 140                 return false;
 141         }
 142
 143         /**
 144          * Get a list of subscribed tags by both the users and the tags that are defined by the admin
 145          *
 146          * @return array
 147          */
 148         public static function getSubscribedTags(): array
 149         {
 150                 $systemTags  = [];
 151                 $server_tags = DI::config()->get('system', 'relay_server_tags');
 152
 153                 foreach (explode(',', mb_strtolower($server_tags)) as $tag) {
 154                         $systemTags[] = trim($tag, '# ');
 155                 }
 156
 157                 if (DI::config()->get('system', 'relay_user_tags')) {
 158                         $userTags = Search::getUserTags();
 159                 } else {
 160                         $userTags = [];
 161                 }
 162
 163                 return array_unique(array_merge($systemTags, $userTags));
 164         }
 165
 166         /**
 167          * Detect the language of a post and decide if the post should be accepted
 168          *
 169          * @param string $body
 170          * @param int    $uri_id
 171          * @param int    $author_id
 172          * @return boolean
 173          */
 174         public static function isWantedLanguage(string $body, int $uri_id = 0, int $author_id = 0)
 175         {
 176                 if (empty($body) || Smilies::isEmojiPost($body)) {
 177                         Logger::debug('Empty body or only emojis', ['body' => $body]);
 178                         return true;
 179                 }
 180
 181                 $languages = [];
 182                 foreach (Item::getLanguageArray($body, 10, $uri_id, $author_id) as $language => $reliability) {
 183                         if ($reliability > 0) {
 184                                 $languages[] = $language;
 185                         }
 186                 }
 187
 188                 Logger::debug('Got languages', ['languages' => $languages, 'body' => $body]);
 189
 190                 if (!empty($languages)) {
 191                         if (in_array($languages[0], DI::config()->get('system', 'relay_deny_languages'))) {
 192                                 Logger::info('Unwanted language found', ['language' => $languages[0]]);
 193                                 return false;
 194                         }
 195                 } elseif (DI::config()->get('system', 'relay_deny_undetected_language')) {
 196                         Logger::info('Undetected language found', ['body' => $body]);
 197                         return false;
 198                 }
 199
 200                 return true;
 201         }
 202
 203         /**
 204          * Update or insert a relay contact
 205          *
 206          * @param array $gserver Global server record
 207          * @param array $fields  Optional network specific fields
 208          * @return void
 209          * @throws \Exception
 210          */
 211         public static function updateContact(array $gserver, array $fields = [])
 212         {
 213                 if (in_array($gserver['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
 214                         $system = APContact::getByURL($gserver['url'] . '/friendica');
 215                         if (!empty($system['sharedinbox'])) {
 216                                 Logger::info('Successfully probed for relay contact', ['server' => $gserver['url']]);
 217                                 $id = Contact::updateFromProbeByURL($system['url']);
 218                                 Logger::info('Updated relay contact', ['server' => $gserver['url'], 'id' => $id]);
 219                                 return;
 220                         }
 221                 }
 222
 223                 $condition = ['uid' => 0, 'gsid' => $gserver['id'], 'contact-type' => Contact::TYPE_RELAY];
 224                 $old = DBA::selectFirst('contact', [], $condition);
 225                 if (!DBA::isResult($old)) {
 226                         $condition = ['uid' => 0, 'nurl' => Strings::normaliseLink($gserver['url'])];
 227                         $old = DBA::selectFirst('contact', [], $condition);
 228                         if (DBA::isResult($old)) {
 229                                 $fields['gsid'] = $gserver['id'];
 230                                 $fields['contact-type'] = Contact::TYPE_RELAY;
 231                                 Logger::info('Assigning missing data for relay contact', ['server' => $gserver['url'], 'id' => $old['id']]);
 232                         }
 233                 } elseif (empty($fields)) {
 234                         Logger::info('No content to update, quitting', ['server' => $gserver['url']]);
 235                         return;
 236                 }
 237
 238                 if (DBA::isResult($old)) {
 239                         $fields['updated'] = DateTimeFormat::utcNow();
 240
 241                         Logger::info('Update relay contact', ['server' => $gserver['url'], 'id' => $old['id'], 'fields' => $fields]);
 242                         Contact::update($fields, ['id' => $old['id']], $old);
 243                 } else {
 244                         $default = ['created' => DateTimeFormat::utcNow(),
 245                                 'name' => 'relay', 'nick' => 'relay', 'url' => $gserver['url'],
 246                                 'nurl' => Strings::normaliseLink($gserver['url']),
 247                                 'network' => Protocol::DIASPORA, 'uid' => 0,
 248                                 'batch' => $gserver['url'] . '/receive/public',
 249                                 'rel' => Contact::FOLLOWER, 'blocked' => false,
 250                                 'pending' => false, 'writable' => true,
 251                                 'gsid' => $gserver['id'],
 252                                 'baseurl' => $gserver['url'], 'contact-type' => Contact::TYPE_RELAY];
 253
 254                         $fields = array_merge($default, $fields);
 255
 256                         Logger::info('Create relay contact', ['server' => $gserver['url'], 'fields' => $fields]);
 257                         Contact::insert($fields);
 258                 }
 259         }
 260
 261         /**
 262          * Mark the relay contact of the given contact for archival
 263          * This is called whenever there is a communication issue with the server.
 264          * It avoids sending stuff to servers who don't exist anymore.
 265          * The relay contact is a technical contact entry that exists once per server.
 266          *
 267          * @param array $contact of the relay contact
 268          * @return void
 269          */
 270         public static function markForArchival(array $contact)
 271         {
 272                 if (!empty($contact['contact-type']) && ($contact['contact-type'] == Contact::TYPE_RELAY)) {
 273                         // This is already the relay contact, we don't need to fetch it
 274                         $relay_contact = $contact;
 275                 } elseif (empty($contact['baseurl'])) {
 276                         if (!empty($contact['batch'])) {
 277                                 $condition = ['uid' => 0, 'network' => Protocol::FEDERATED, 'batch' => $contact['batch'], 'contact-type' => Contact::TYPE_RELAY];
 278                                 $relay_contact = DBA::selectFirst('contact', [], $condition);
 279                         } else {
 280                                 return;
 281                         }
 282                 } else {
 283                         $gserver = ['id' => $contact['gsid'] ?: GServer::getID($contact['baseurl'], true),
 284                                 'url' => $contact['baseurl'], 'network' => $contact['network']];
 285                         $relay_contact = self::getContact($gserver, []);
 286                 }
 287
 288                 if (!empty($relay_contact)) {
 289                         Logger::info('Relay contact will be marked for archival', ['id' => $relay_contact['id'], 'url' => $relay_contact['url']]);
 290                         Contact::markForArchival($relay_contact);
 291                 }
 292         }
 293
 294         /**
 295          * Return a list of servers that we serve via the direct relay
 296          *
 297          * @param integer $item_id  id of the item that is sent
 298          * @param array   $contacts Previously fetched contacts
 299          * @param array   $networks Networks of the relay servers
 300          * @return array of relay servers
 301          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 302          */
 303         public static function getDirectRelayList(int $item_id): array
 304         {
 305                 $serverlist = [];
 306
 307                 if (!DI::config()->get('system', 'relay_directly', false)) {
 308                         return [];
 309                 }
 310
 311                 // We distribute our stuff based on the parent to ensure that the thread will be complete
 312                 $parent = Post::selectFirst(['uri-id'], ['id' => $item_id]);
 313                 if (!DBA::isResult($parent)) {
 314                         return [];
 315                 }
 316
 317                 // Servers that want to get all content
 318                 $servers = DBA::select('gserver', ['id', 'url', 'network'], ['relay-subscribe' => true, 'relay-scope' => 'all']);
 319                 while ($server = DBA::fetch($servers)) {
 320                         $serverlist[$server['id']] = $server;
 321                 }
 322                 DBA::close($servers);
 323
 324                 // All tags of the current post
 325                 $tags = DBA::select('tag-view', ['name'], ['uri-id' => $parent['uri-id'], 'type' => Tag::HASHTAG]);
 326                 $taglist = [];
 327                 while ($tag = DBA::fetch($tags)) {
 328                         $taglist[] = $tag['name'];
 329                 }
 330                 DBA::close($tags);
 331
 332                 // All servers who wants content with this tag
 333                 $tagserverlist = [];
 334                 if (!empty($taglist)) {
 335                         $tagserver = DBA::select('gserver-tag', ['gserver-id'], ['tag' => $taglist]);
 336                         while ($server = DBA::fetch($tagserver)) {
 337                                 $tagserverlist[] = $server['gserver-id'];
 338                         }
 339                         DBA::close($tagserver);
 340                 }
 341
 342                 // All addresses with the given id
 343                 if (!empty($tagserverlist)) {
 344                         $servers = DBA::select('gserver', ['id', 'url', 'network'], ['relay-subscribe' => true, 'relay-scope' => 'tags', 'id' => $tagserverlist]);
 345                         while ($server = DBA::fetch($servers)) {
 346                                 $serverlist[$server['id']] = $server;
 347                         }
 348                         DBA::close($servers);
 349                 }
 350
 351                 $contacts = [];
 352
 353                 // Now we are collecting all relay contacts
 354                 foreach ($serverlist as $gserver) {
 355                         // We don't send messages to ourselves
 356                         if (Strings::compareLink($gserver['url'], DI::baseUrl())) {
 357                                 continue;
 358                         }
 359                         $contact = self::getContact($gserver);
 360                         if (empty($contact)) {
 361                                 continue;
 362                         }
 363                 }
 364
 365                 return $contacts;
 366         }
 367
 368         /**
 369          * Return a list of relay servers
 370          *
 371          * @param array $fields Field list
 372          * @return array List of relay servers
 373          * @throws Exception
 374          */
 375         public static function getList(array $fields = []): array
 376         {
 377                 return DBA::selectToArray('apcontact', $fields,
 378                         ["`type` IN (?, ?) AND `url` IN (SELECT `url` FROM `contact` WHERE `uid` = ? AND `rel` = ?)", 'Application', 'Service', 0, Contact::FRIEND]);
 379         }
 380
 381         /**
 382          * Return a contact for a given server address or creates a dummy entry
 383          *
 384          * @param array $gserver Global server record
 385          * @param array $fields  Fieldlist
 386          * @return array|bool Array with the contact or false on error
 387          * @throws \Exception
 388          */
 389         private static function getContact(array $gserver, array $fields = ['batch', 'id', 'url', 'name', 'network', 'protocol', 'archive', 'blocked'])
 390         {
 391                 // Fetch the relay contact
 392                 $condition = ['uid' => 0, 'gsid' => $gserver['id'], 'contact-type' => Contact::TYPE_RELAY];
 393                 $contact = DBA::selectFirst('contact', $fields, $condition);
 394                 if (DBA::isResult($contact)) {
 395                         if ($contact['archive'] || $contact['blocked']) {
 396                                 return false;
 397                         }
 398                         return $contact;
 399                 } else {
 400                         self::updateContact($gserver);
 401
 402                         $contact = DBA::selectFirst('contact', $fields, $condition);
 403                         if (DBA::isResult($contact)) {
 404                                 return $contact;
 405                         }
 406                 }
 407
 408                 // It should never happen that we arrive here
 409                 return [];
 410         }
 411
 412         /**
 413          * Resubscribe to all relay servers
 414          *
 415          * @return void
 416          */
 417         public static function reSubscribe()
 418         {
 419                 foreach (self::getList() as $server) {
 420                         $success = ActivityPub\Transmitter::sendRelayFollow($server['url']);
 421                         Logger::debug('Resubscribed', ['profile' => $server['url'], 'success' => $success]);
 422                 }
 423         }
 424 }