src/Protocol/ActivityPub.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\Core\Logger;
  25 use Friendica\Core\Protocol;
  26 use Friendica\Model\APContact;
  27 use Friendica\Model\User;
  28 use Friendica\Util\HTTPSignature;
  29 use Friendica\Util\JsonLD;
  30
  31 /**
  32  * ActivityPub Protocol class
  33  *
  34  * The ActivityPub Protocol is a message exchange protocol defined by the W3C.
  35  * https://www.w3.org/TR/activitypub/
  36  * https://www.w3.org/TR/activitystreams-core/
  37  * https://www.w3.org/TR/activitystreams-vocabulary/
  38  *
  39  * https://blog.joinmastodon.org/2018/06/how-to-implement-a-basic-activitypub-server/
  40  * https://blog.joinmastodon.org/2018/07/how-to-make-friends-and-verify-requests/
  41  *
  42  * Digest: https://tools.ietf.org/html/rfc5843
  43  * https://tools.ietf.org/html/draft-cavage-http-signatures-10#ref-15
  44  *
  45  * Mastodon implementation of supported activities:
  46  * https://github.com/tootsuite/mastodon/blob/master/app/lib/activitypub/activity.rb#L26
  47  *
  48  * Funkwhale:
  49  * http://docs-funkwhale-funkwhale-549-music-federation-documentation.preview.funkwhale.audio/federation/index.html
  50  *
  51  * To-do:
  52  * - Polling the outboxes for missing content?
  53  *
  54  * Missing parts from DFRN:
  55  * - Public Group
  56  * - Private Group
  57  * - Relocation
  58  */
  59 class ActivityPub
  60 {
  61         const PUBLIC_COLLECTION = 'https://www.w3.org/ns/activitystreams#Public';
  62         const CONTEXT = ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1',
  63                 ['vcard' => 'http://www.w3.org/2006/vcard/ns#',
  64                 'dfrn' => 'http://purl.org/macgirvin/dfrn/1.0/',
  65                 'diaspora' => 'https://diasporafoundation.org/ns/',
  66                 'litepub' => 'http://litepub.social/ns#',
  67                 'toot' => 'http://joinmastodon.org/ns#',
  68                 'featured' => [
  69                         "@id" => "toot:featured",
  70                         "@type" => "@id",
  71                 ],
  72                 'schema' => 'http://schema.org#',
  73                 'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers',
  74                 'sensitive' => 'as:sensitive', 'Hashtag' => 'as:Hashtag',
  75                 'quoteUrl' => 'as:quoteUrl',
  76                 'conversation' => 'ostatus:conversation',
  77                 'directMessage' => 'litepub:directMessage',
  78                 'discoverable' => 'toot:discoverable',
  79                 'PropertyValue' => 'schema:PropertyValue',
  80                 'value' => 'schema:value',
  81         ]];
  82         const ACCOUNT_TYPES = ['Person', 'Organization', 'Service', 'Group', 'Application', 'Tombstone'];
  83         /**
  84          * Checks if the web request is done for the AP protocol
  85          *
  86          * @return bool is it AP?
  87          */
  88         public static function isRequest(): bool
  89         {
  90                 header('Vary: Accept', false);
  91
  92                 $isrequest = stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/activity+json') ||
  93                         stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/json') ||
  94                         stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/ld+json');
  95
  96                 if ($isrequest) {
  97                         Logger::debug('Is AP request', ['accept' => $_SERVER['HTTP_ACCEPT'], 'agent' => $_SERVER['HTTP_USER_AGENT'] ?? '']);
  98                 }
  99
 100                 return $isrequest;
 101         }
 102
 103         /**
 104          * Fetches ActivityPub content from the given url
 105          *
 106          * @param string  $url content url
 107          * @param integer $uid User ID for the signature
 108          * @return array
 109          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 110          */
 111         public static function fetchContent(string $url, int $uid = 0): array
 112         {
 113                 return HTTPSignature::fetch($url, $uid);
 114         }
 115
 116         private static function getAccountType(array $apcontact): int
 117         {
 118                 $accounttype = -1;
 119
 120                 switch($apcontact['type']) {
 121                         case 'Person':
 122                                 $accounttype = User::ACCOUNT_TYPE_PERSON;
 123                                 break;
 124                         case 'Organization':
 125                                 $accounttype = User::ACCOUNT_TYPE_ORGANISATION;
 126                                 break;
 127                         case 'Service':
 128                                 $accounttype = User::ACCOUNT_TYPE_NEWS;
 129                                 break;
 130                         case 'Group':
 131                                 $accounttype = User::ACCOUNT_TYPE_COMMUNITY;
 132                                 break;
 133                         case 'Application':
 134                                 $accounttype = User::ACCOUNT_TYPE_RELAY;
 135                                 break;
 136                         case 'Tombstone':
 137                                 $accounttype = User::ACCOUNT_TYPE_DELETED;
 138                                 break;
 139                 }
 140
 141                 return $accounttype;
 142         }
 143
 144         /**
 145          * Fetches a profile from the given url into an array that is compatible to Probe::uri
 146          *
 147          * @param string  $url    profile url
 148          * @param boolean $update Update the profile
 149          * @return array
 150          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 151          * @throws \ImagickException
 152          */
 153         public static function probeProfile(string $url, bool $update = true): array
 154         {
 155                 $apcontact = APContact::getByURL($url, $update);
 156                 if (empty($apcontact)) {
 157                         return [];
 158                 }
 159
 160                 $profile = ['network' => Protocol::ACTIVITYPUB];
 161                 $profile['nick'] = $apcontact['nick'];
 162                 $profile['name'] = $apcontact['name'];
 163                 $profile['guid'] = $apcontact['uuid'];
 164                 $profile['url'] = $apcontact['url'];
 165                 $profile['addr'] = $apcontact['addr'];
 166                 $profile['alias'] = $apcontact['alias'];
 167                 $profile['following'] = $apcontact['following'];
 168                 $profile['followers'] = $apcontact['followers'];
 169                 $profile['inbox'] = $apcontact['inbox'];
 170                 $profile['outbox'] = $apcontact['outbox'];
 171                 $profile['sharedinbox'] = $apcontact['sharedinbox'];
 172                 $profile['photo'] = $apcontact['photo'];
 173                 $profile['header'] = $apcontact['header'];
 174                 $profile['account-type'] = self::getAccountType($apcontact);
 175                 $profile['community'] = ($profile['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
 176                 // $profile['keywords']
 177                 // $profile['location']
 178                 $profile['about'] = $apcontact['about'];
 179                 $profile['xmpp'] = $apcontact['xmpp'];
 180                 $profile['matrix'] = $apcontact['matrix'];
 181                 $profile['batch'] = $apcontact['sharedinbox'];
 182                 $profile['notify'] = $apcontact['inbox'];
 183                 $profile['poll'] = $apcontact['outbox'];
 184                 $profile['pubkey'] = $apcontact['pubkey'];
 185                 $profile['subscribe'] = $apcontact['subscribe'];
 186                 $profile['manually-approve'] = $apcontact['manually-approve'];
 187                 $profile['baseurl'] = $apcontact['baseurl'];
 188                 $profile['gsid'] = $apcontact['gsid'];
 189
 190                 if (!is_null($apcontact['discoverable'])) {
 191                         $profile['hide'] = !$apcontact['discoverable'];
 192                 }
 193
 194                 // Remove all "null" fields
 195                 foreach ($profile as $field => $content) {
 196                         if (is_null($content)) {
 197                                 unset($profile[$field]);
 198                         }
 199                 }
 200
 201                 return $profile;
 202         }
 203
 204         /**
 205          * Fetches activities from the outbox of a given profile and processes it
 206          *
 207          * @param string  $url
 208          * @param integer $uid User ID
 209          * @return void
 210          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 211          */
 212         public static function fetchOutbox(string $url, int $uid)
 213         {
 214                 $data = self::fetchContent($url, $uid);
 215                 if (empty($data)) {
 216                         return;
 217                 }
 218
 219                 if (!empty($data['orderedItems'])) {
 220                         $items = $data['orderedItems'];
 221                 } elseif (!empty($data['first']['orderedItems'])) {
 222                         $items = $data['first']['orderedItems'];
 223                 } elseif (!empty($data['first'])) {
 224                         self::fetchOutbox($data['first'], $uid);
 225                         return;
 226                 } else {
 227                         $items = [];
 228                 }
 229
 230                 foreach ($items as $activity) {
 231                         $ldactivity = JsonLD::compact($activity);
 232                         ActivityPub\Receiver::processActivity($ldactivity, '', $uid, true);
 233                 }
 234         }
 235
 236         /**
 237          * Fetch items from AP endpoints
 238          *
 239          * @param string $url  Address of the endpoint
 240          * @param integer $uid Optional user id
 241          * @return array Endpoint items
 242          */
 243         public static function fetchItems(string $url, int $uid = 0): array
 244         {
 245                 $data = self::fetchContent($url, $uid);
 246                 if (empty($data)) {
 247                         return [];
 248                 }
 249
 250                 if (!empty($data['orderedItems'])) {
 251                         $items = $data['orderedItems'];
 252                 } elseif (!empty($data['first']['orderedItems'])) {
 253                         $items = $data['first']['orderedItems'];
 254                 } elseif (!empty($data['first']) && is_string($data['first']) && ($data['first'] != $url)) {
 255                         return self::fetchItems($data['first'], $uid);
 256                 } else {
 257                         return [];
 258                 }
 259
 260                 if (!empty($data['next']) && is_string($data['next'])) {
 261                         $items = array_merge($items, self::fetchItems($data['next'], $uid));
 262                 }
 263
 264                 return $items;
 265         }
 266
 267         /**
 268          * Checks if the given contact url does support ActivityPub
 269          *
 270          * @param string  $url    profile url
 271          * @param boolean $update true = always update, false = never update, null = update when not found or outdated
 272          * @return boolean
 273          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 274          * @throws \ImagickException
 275          */
 276         public static function isSupportedByContactUrl(string $url, $update = null): bool
 277         {
 278                 return !empty(APContact::getByURL($url, $update));
 279         }
 280 }