src/Protocol/Relay.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2022, 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 = ''): 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                 $body = ActivityPub\Processor::normalizeMentionLinks($body);
  81
  82                 $systemTags = [];
  83                 $userTags = [];
  84                 $denyTags = [];
  85
  86                 if ($scope == self::SCOPE_TAGS) {
  87                         $server_tags = $config->get('system', 'relay_server_tags');
  88                         $tagitems = explode(',', mb_strtolower($server_tags));
  89                         foreach ($tagitems as $tag) {
  90                                 $systemTags[] = trim($tag, '# ');
  91                         }
  92
  93                         if ($config->get('system', 'relay_user_tags')) {
  94                                 $userTags = Search::getUserTags();
  95                         }
  96                 }
  97
  98                 $tagList = array_unique(array_merge($systemTags, $userTags));
  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' => $url]);
 114                                         return false;
 115                                 }
 116
 117                                 if (in_array($tag, $tagList)) {
 118                                         Logger::info('Subscribed hashtag found - accepted', ['hashtag' => $tag, 'network' => $network, 'url' => $url]);
 119                                         return true;
 120                                 }
 121
 122                                 // We check with "strpos" for performance issues. Only when this is true, the regular expression check is used
 123                                 // RegExp is taken from here: https://medium.com/@shiba1014/regex-word-boundaries-with-unicode-207794f6e7ed
 124                                 if ((strpos($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]);
 126                                         return true;
 127                                 }
 128                         }
 129                 }
 130
 131                 $languages = [];
 132                 foreach (Item::getLanguageArray($body, 10) as $language => $reliability) {
 133                         if ($reliability > 0) {
 134                                 $languages[] = $language;
 135                         }
 136                 }
 137
 138                 Logger::debug('Got languages', ['languages' => $languages, 'body' => $body]);
 139
 140                 if (!empty($languages)) {
 141                         if (in_array($languages[0], $config->get('system', 'relay_deny_languages'))) {
 142                                 Logger::info('Unwanted language found - rejected', ['language' => $languages[0], 'network' => $network, 'url' => $url]);
 143                                 return false;
 144                         }
 145                 } elseif ($config->get('system', 'relay_deny_undetected_language')) {
 146                         Logger::info('Undetected language found - rejected', ['body' => $body, 'network' => $network, 'url' => $url]);
 147                         return false;
 148                 }
 149
 150                 if ($scope == self::SCOPE_ALL) {
 151                         Logger::info('Server accept all posts - accepted', ['network' => $network, 'url' => $url]);
 152                         return true;
 153                 }
 154
 155                 Logger::info('No matching hashtags found - rejected', ['network' => $network, 'url' => $url]);
 156                 return false;
 157         }
 158
 159         /**
 160          * Update or insert a relay contact
 161          *
 162          * @param array $gserver Global server record
 163          * @param array $fields  Optional network specific fields
 164          * @return void
 165          * @throws \Exception
 166          */
 167         public static function updateContact(array $gserver, array $fields = [])
 168         {
 169                 if (in_array($gserver['network'], [Protocol::ACTIVITYPUB, Protocol::DFRN])) {
 170                         $system = APContact::getByURL($gserver['url'] . '/friendica');
 171                         if (!empty($system['sharedinbox'])) {
 172                                 Logger::info('Sucessfully probed for relay contact', ['server' => $gserver['url']]);
 173                                 $id = Contact::updateFromProbeByURL($system['url']);
 174                                 Logger::info('Updated relay contact', ['server' => $gserver['url'], 'id' => $id]);
 175                                 return;
 176                         }
 177                 }
 178
 179                 $condition = ['uid' => 0, 'gsid' => $gserver['id'], 'contact-type' => Contact::TYPE_RELAY];
 180                 $old = DBA::selectFirst('contact', [], $condition);
 181                 if (!DBA::isResult($old)) {
 182                         $condition = ['uid' => 0, 'nurl' => Strings::normaliseLink($gserver['url'])];
 183                         $old = DBA::selectFirst('contact', [], $condition);
 184                         if (DBA::isResult($old)) {
 185                                 $fields['gsid'] = $gserver['id'];
 186                                 $fields['contact-type'] = Contact::TYPE_RELAY;
 187                                 Logger::info('Assigning missing data for relay contact', ['server' => $gserver['url'], 'id' => $old['id']]);
 188                         }
 189                 } elseif (empty($fields)) {
 190                         Logger::info('No content to update, quitting', ['server' => $gserver['url']]);
 191                         return;
 192                 }
 193
 194                 if (DBA::isResult($old)) {
 195                         $fields['updated'] = DateTimeFormat::utcNow();
 196
 197                         Logger::info('Update relay contact', ['server' => $gserver['url'], 'id' => $old['id'], 'fields' => $fields]);
 198                         Contact::update($fields, ['id' => $old['id']], $old);
 199                 } else {
 200                         $default = ['created' => DateTimeFormat::utcNow(),
 201                                 'name' => 'relay', 'nick' => 'relay', 'url' => $gserver['url'],
 202                                 'nurl' => Strings::normaliseLink($gserver['url']),
 203                                 'network' => Protocol::DIASPORA, 'uid' => 0,
 204                                 'batch' => $gserver['url'] . '/receive/public',
 205                                 'rel' => Contact::FOLLOWER, 'blocked' => false,
 206                                 'pending' => false, 'writable' => true,
 207                                 'gsid' => $gserver['id'],
 208                                 'baseurl' => $gserver['url'], 'contact-type' => Contact::TYPE_RELAY];
 209
 210                         $fields = array_merge($default, $fields);
 211
 212                         Logger::info('Create relay contact', ['server' => $gserver['url'], 'fields' => $fields]);
 213                         Contact::insert($fields);
 214                 }
 215         }
 216
 217         /**
 218          * Mark the relay contact of the given contact for archival
 219          * This is called whenever there is a communication issue with the server.
 220          * It avoids sending stuff to servers who don't exist anymore.
 221          * The relay contact is a technical contact entry that exists once per server.
 222          *
 223          * @param array $contact of the relay contact
 224          * @return void
 225          */
 226         public static function markForArchival(array $contact)
 227         {
 228                 if (!empty($contact['contact-type']) && ($contact['contact-type'] == Contact::TYPE_RELAY)) {
 229                         // This is already the relay contact, we don't need to fetch it
 230                         $relay_contact = $contact;
 231                 } elseif (empty($contact['baseurl'])) {
 232                         if (!empty($contact['batch'])) {
 233                                 $condition = ['uid' => 0, 'network' => Protocol::FEDERATED, 'batch' => $contact['batch'], 'contact-type' => Contact::TYPE_RELAY];
 234                                 $relay_contact = DBA::selectFirst('contact', [], $condition);
 235                         } else {
 236                                 return;
 237                         }
 238                 } else {
 239                         $gserver = ['id' => $contact['gsid'] ?: GServer::getID($contact['baseurl'], true),
 240                                 'url' => $contact['baseurl'], 'network' => $contact['network']];
 241                         $relay_contact = self::getContact($gserver, []);
 242                 }
 243
 244                 if (!empty($relay_contact)) {
 245                         Logger::info('Relay contact will be marked for archival', ['id' => $relay_contact['id'], 'url' => $relay_contact['url']]);
 246                         Contact::markForArchival($relay_contact);
 247                 }
 248         }
 249
 250         /**
 251          * Return a list of servers that we serve via the direct relay
 252          *
 253          * @param integer $item_id  id of the item that is sent
 254          * @param array   $contacts Previously fetched contacts
 255          * @param array   $networks Networks of the relay servers
 256          * @return array of relay servers
 257          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 258          */
 259         public static function getDirectRelayList(int $item_id): array
 260         {
 261                 $serverlist = [];
 262
 263                 if (!DI::config()->get('system', 'relay_directly', false)) {
 264                         return [];
 265                 }
 266
 267                 // We distribute our stuff based on the parent to ensure that the thread will be complete
 268                 $parent = Post::selectFirst(['uri-id'], ['id' => $item_id]);
 269                 if (!DBA::isResult($parent)) {
 270                         return [];
 271                 }
 272
 273                 // Servers that want to get all content
 274                 $servers = DBA::select('gserver', ['id', 'url', 'network'], ['relay-subscribe' => true, 'relay-scope' => 'all']);
 275                 while ($server = DBA::fetch($servers)) {
 276                         $serverlist[$server['id']] = $server;
 277                 }
 278                 DBA::close($servers);
 279
 280                 // All tags of the current post
 281                 $tags = DBA::select('tag-view', ['name'], ['uri-id' => $parent['uri-id'], 'type' => Tag::HASHTAG]);
 282                 $taglist = [];
 283                 while ($tag = DBA::fetch($tags)) {
 284                         $taglist[] = $tag['name'];
 285                 }
 286                 DBA::close($tags);
 287
 288                 // All servers who wants content with this tag
 289                 $tagserverlist = [];
 290                 if (!empty($taglist)) {
 291                         $tagserver = DBA::select('gserver-tag', ['gserver-id'], ['tag' => $taglist]);
 292                         while ($server = DBA::fetch($tagserver)) {
 293                                 $tagserverlist[] = $server['gserver-id'];
 294                         }
 295                         DBA::close($tagserver);
 296                 }
 297
 298                 // All adresses with the given id
 299                 if (!empty($tagserverlist)) {
 300                         $servers = DBA::select('gserver', ['id', 'url', 'network'], ['relay-subscribe' => true, 'relay-scope' => 'tags', 'id' => $tagserverlist]);
 301                         while ($server = DBA::fetch($servers)) {
 302                                 $serverlist[$server['id']] = $server;
 303                         }
 304                         DBA::close($servers);
 305                 }
 306
 307                 $contacts = [];
 308
 309                 // Now we are collecting all relay contacts
 310                 foreach ($serverlist as $gserver) {
 311                         // We don't send messages to ourselves
 312                         if (Strings::compareLink($gserver['url'], DI::baseUrl())) {
 313                                 continue;
 314                         }
 315                         $contact = self::getContact($gserver);
 316                         if (empty($contact)) {
 317                                 continue;
 318                         }
 319                 }
 320
 321                 return $contacts;
 322         }
 323
 324         /**
 325          * Return a list of relay servers
 326          *
 327          * @param array $fields Field list
 328          * @return array List of relay servers
 329          * @throws Exception
 330          */
 331         public static function getList(array $fields = []): array
 332         {
 333                 return DBA::selectToArray('apcontact', $fields,
 334                         ["`type` = ? AND `url` IN (SELECT `url` FROM `contact` WHERE `uid` = ? AND `rel` = ?)", 'Application', 0, Contact::FRIEND]);
 335         }
 336
 337         /**
 338          * Return a contact for a given server address or creates a dummy entry
 339          *
 340          * @param array $gserver Global server record
 341          * @param array $fields  Fieldlist
 342          * @return array|bool Array with the contact or false on error
 343          * @throws \Exception
 344          */
 345         private static function getContact(array $gserver, array $fields = ['batch', 'id', 'url', 'name', 'network', 'protocol', 'archive', 'blocked'])
 346         {
 347                 // Fetch the relay contact
 348                 $condition = ['uid' => 0, 'gsid' => $gserver['id'], 'contact-type' => Contact::TYPE_RELAY];
 349                 $contact = DBA::selectFirst('contact', $fields, $condition);
 350                 if (DBA::isResult($contact)) {
 351                         if ($contact['archive'] || $contact['blocked']) {
 352                                 return false;
 353                         }
 354                         return $contact;
 355                 } else {
 356                         self::updateContact($gserver);
 357
 358                         $contact = DBA::selectFirst('contact', $fields, $condition);
 359                         if (DBA::isResult($contact)) {
 360                                 return $contact;
 361                         }
 362                 }
 363
 364                 // It should never happen that we arrive here
 365                 return [];
 366         }
 367
 368         /**
 369          * Resubscribe to all relay servers
 370          *
 371          * @return void
 372          */
 373         public static function reSubscribe()
 374         {
 375                 foreach (self::getList() as $server) {
 376                         $success = ActivityPub\Transmitter::sendRelayFollow($server['url']);
 377                         Logger::debug('Resubscribed', ['profile' => $server['url'], 'success' => $success]);
 378                 }
 379         }
 380 }