src/Protocol/ActivityPub.php

   1 <?php
   2 /**
   3  * @copyright Copyright (C) 2010-2021, 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 Forum
  56  * - Private Forum
  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                 'schema' => 'http://schema.org#',
  69                 'manuallyApprovesFollowers' => 'as:manuallyApprovesFollowers',
  70                 'sensitive' => 'as:sensitive', 'Hashtag' => 'as:Hashtag',
  71                 'directMessage' => 'litepub:directMessage',
  72                 'discoverable' => 'toot:discoverable',
  73                 'PropertyValue' => 'schema:PropertyValue',
  74                 'value' => 'schema:value',
  75         ]];
  76         const ACCOUNT_TYPES = ['Person', 'Organization', 'Service', 'Group', 'Application', 'Tombstone'];
  77         /**
  78          * Checks if the web request is done for the AP protocol
  79          *
  80          * @return bool is it AP?
  81          */
  82         public static function isRequest()
  83         {
  84                 $isrequest = stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/activity+json') ||
  85                         stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/json') ||
  86                         stristr($_SERVER['HTTP_ACCEPT'] ?? '', 'application/ld+json');
  87
  88                 if ($isrequest) {
  89                         Logger::debug('Is AP request', ['accept' => $_SERVER['HTTP_ACCEPT'], 'agent' => $_SERVER['HTTP_USER_AGENT'] ?? '']);
  90                 }
  91
  92                 return $isrequest;
  93         }
  94
  95         /**
  96          * Fetches ActivityPub content from the given url
  97          *
  98          * @param string  $url content url
  99          * @param integer $uid User ID for the signature
 100          * @return array
 101          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 102          */
 103         public static function fetchContent(string $url, int $uid = 0)
 104         {
 105                 return HTTPSignature::fetch($url, $uid);
 106         }
 107
 108         private static function getAccountType($apcontact)
 109         {
 110                 $accounttype = -1;
 111
 112                 switch($apcontact['type']) {
 113                         case 'Person':
 114                                 $accounttype = User::ACCOUNT_TYPE_PERSON;
 115                                 break;
 116                         case 'Organization':
 117                                 $accounttype = User::ACCOUNT_TYPE_ORGANISATION;
 118                                 break;
 119                         case 'Service':
 120                                 $accounttype = User::ACCOUNT_TYPE_NEWS;
 121                                 break;
 122                         case 'Group':
 123                                 $accounttype = User::ACCOUNT_TYPE_COMMUNITY;
 124                                 break;
 125                         case 'Application':
 126                                 $accounttype = User::ACCOUNT_TYPE_RELAY;
 127                                 break;
 128                         case 'Tombstone':
 129                                 $accounttype = User::ACCOUNT_TYPE_DELETED;
 130                                 break;
 131                 }
 132
 133                 return $accounttype;
 134         }
 135
 136         /**
 137          * Fetches a profile from the given url into an array that is compatible to Probe::uri
 138          *
 139          * @param string  $url    profile url
 140          * @param boolean $update Update the profile
 141          * @return array
 142          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 143          * @throws \ImagickException
 144          */
 145         public static function probeProfile($url, $update = true)
 146         {
 147                 $apcontact = APContact::getByURL($url, $update);
 148                 if (empty($apcontact)) {
 149                         return [];
 150                 }
 151
 152                 $profile = ['network' => Protocol::ACTIVITYPUB];
 153                 $profile['nick'] = $apcontact['nick'];
 154                 $profile['name'] = $apcontact['name'];
 155                 $profile['guid'] = $apcontact['uuid'];
 156                 $profile['url'] = $apcontact['url'];
 157                 $profile['addr'] = $apcontact['addr'];
 158                 $profile['alias'] = $apcontact['alias'];
 159                 $profile['following'] = $apcontact['following'];
 160                 $profile['followers'] = $apcontact['followers'];
 161                 $profile['inbox'] = $apcontact['inbox'];
 162                 $profile['outbox'] = $apcontact['outbox'];
 163                 $profile['sharedinbox'] = $apcontact['sharedinbox'];
 164                 $profile['photo'] = $apcontact['photo'];
 165                 $profile['header'] = $apcontact['header'];
 166                 $profile['account-type'] = self::getAccountType($apcontact);
 167                 $profile['community'] = ($profile['account-type'] == User::ACCOUNT_TYPE_COMMUNITY);
 168                 // $profile['keywords']
 169                 // $profile['location']
 170                 $profile['about'] = $apcontact['about'];
 171                 $profile['xmpp'] = $apcontact['xmpp'];
 172                 $profile['matrix'] = $apcontact['matrix'];
 173                 $profile['batch'] = $apcontact['sharedinbox'];
 174                 $profile['notify'] = $apcontact['inbox'];
 175                 $profile['poll'] = $apcontact['outbox'];
 176                 $profile['pubkey'] = $apcontact['pubkey'];
 177                 $profile['subscribe'] = $apcontact['subscribe'];
 178                 $profile['manually-approve'] = $apcontact['manually-approve'];
 179                 $profile['baseurl'] = $apcontact['baseurl'];
 180                 $profile['gsid'] = $apcontact['gsid'];
 181
 182                 if (!is_null($apcontact['discoverable'])) {
 183                         $profile['hide'] = !$apcontact['discoverable'];
 184                 }
 185
 186                 // Remove all "null" fields
 187                 foreach ($profile as $field => $content) {
 188                         if (is_null($content)) {
 189                                 unset($profile[$field]);
 190                         }
 191                 }
 192
 193                 return $profile;
 194         }
 195
 196         /**
 197          * Fetches activities from the outbox of a given profile and processes it
 198          *
 199          * @param string  $url
 200          * @param integer $uid User ID
 201          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 202          */
 203         public static function fetchOutbox($url, $uid)
 204         {
 205                 $data = self::fetchContent($url, $uid);
 206                 if (empty($data)) {
 207                         return;
 208                 }
 209
 210                 if (!empty($data['orderedItems'])) {
 211                         $items = $data['orderedItems'];
 212                 } elseif (!empty($data['first']['orderedItems'])) {
 213                         $items = $data['first']['orderedItems'];
 214                 } elseif (!empty($data['first'])) {
 215                         self::fetchOutbox($data['first'], $uid);
 216                         return;
 217                 } else {
 218                         $items = [];
 219                 }
 220
 221                 foreach ($items as $activity) {
 222                         $ldactivity = JsonLD::compact($activity);
 223                         ActivityPub\Receiver::processActivity($ldactivity, '', $uid, true);
 224                 }
 225         }
 226
 227         /**
 228          * Fetch items from AP endpoints
 229          *
 230          * @param string $url  Address of the endpoint
 231          * @param integer $uid Optional user id
 232          * @return array Endpoint items
 233          */
 234         public static function fetchItems(string $url, int $uid = 0)
 235         {
 236                 $data = self::fetchContent($url, $uid);
 237                 if (empty($data)) {
 238                         return [];
 239                 }
 240
 241                 if (!empty($data['orderedItems'])) {
 242                         $items = $data['orderedItems'];
 243                 } elseif (!empty($data['first']['orderedItems'])) {
 244                         $items = $data['first']['orderedItems'];
 245                 } elseif (!empty($data['first']) && is_string($data['first']) && ($data['first'] != $url)) {
 246                         return self::fetchItems($data['first'], $uid);
 247                 } else {
 248                         return [];
 249                 }
 250
 251                 if (!empty($data['next']) && is_string($data['next'])) {
 252                         $items = array_merge($items, self::fetchItems($data['next'], $uid));
 253                 }
 254
 255                 return $items;
 256         }
 257
 258         /**
 259          * Checks if the given contact url does support ActivityPub
 260          *
 261          * @param string  $url    profile url
 262          * @param boolean $update true = always update, false = never update, null = update when not found or outdated
 263          * @return boolean
 264          * @throws \Friendica\Network\HTTPException\InternalServerErrorException
 265          * @throws \ImagickException
 266          */
 267         public static function isSupportedByContactUrl($url, $update = null)
 268         {
 269                 return !empty(APContact::getByURL($url, $update));
 270         }
 271 }