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