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