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