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