3 * @copyright Copyright (C) 2020, Friendica
5 * @license GNU AGPL version 3 or any later version
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.
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.
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/>.
23 use Friendica\Core\Logger;
24 use Friendica\Database\DBA;
26 use Friendica\Model\PushSubscriber;
27 use Friendica\Util\Network;
28 use Friendica\Util\Strings;
30 function post_var($name) {
31 return !empty($_POST[$name]) ? Strings::escapeTags(trim($_POST[$name])) : '';
34 function pubsubhubbub_init(App $a) {
35 // PuSH subscription must be considered "public" so just block it
36 // if public access isn't enabled.
37 if (DI::config()->get('system', 'block_public')) {
38 throw new \Friendica\Network\HTTPException\ForbiddenException();
41 // Subscription request from subscriber
42 // https://pubsubhubbub.googlecode.com/git/pubsubhubbub-core-0.4.html#anchor4
43 // Example from GNU Social:
44 // [hub_mode] => subscribe
45 // [hub_callback] => http://status.local/main/push/callback/1
46 // [hub_verify] => sync
47 // [hub_verify_token] => af11...
48 // [hub_secret] => af11...
49 // [hub_topic] => http://friendica.local/dfrn_poll/sazius
51 if ($_SERVER['REQUEST_METHOD'] === 'POST') {
52 $hub_mode = post_var('hub_mode');
53 $hub_callback = post_var('hub_callback');
54 $hub_verify_token = post_var('hub_verify_token');
55 $hub_secret = post_var('hub_secret');
56 $hub_topic = post_var('hub_topic');
58 // check for valid hub_mode
59 if ($hub_mode === 'subscribe') {
61 } elseif ($hub_mode === 'unsubscribe') {
64 Logger::log("Invalid hub_mode=$hub_mode, ignoring.");
65 throw new \Friendica\Network\HTTPException\NotFoundException();
68 Logger::log("$hub_mode request from " . $_SERVER['REMOTE_ADDR']);
71 // Normally the url should now contain the nick name as last part of the url
74 // Get the nick name from the topic as a fallback
77 // Extract nick name and strip any .atom extension
78 $nick = basename($nick, '.atom');
81 Logger::log('Bad hub_topic=$hub_topic, ignoring.');
82 throw new \Friendica\Network\HTTPException\NotFoundException();
85 // fetch user from database given the nickname
86 $condition = ['nickname' => $nick, 'account_expired' => false, 'account_removed' => false];
87 $owner = DBA::selectFirst('user', ['uid', 'nickname'], $condition);
88 if (!DBA::isResult($owner)) {
89 Logger::log('Local account not found: ' . $nick . ' - topic: ' . $hub_topic . ' - callback: ' . $hub_callback);
90 throw new \Friendica\Network\HTTPException\NotFoundException();
93 // get corresponding row from contact table
94 $condition = ['uid' => $owner['uid'], 'blocked' => false,
95 'pending' => false, 'self' => true];
96 $contact = DBA::selectFirst('contact', ['poll'], $condition);
97 if (!DBA::isResult($contact)) {
98 Logger::log('Self contact for user ' . $owner['uid'] . ' not found.');
99 throw new \Friendica\Network\HTTPException\NotFoundException();
102 // sanity check that topic URLs are the same
103 $hub_topic2 = str_replace('/feed/', '/dfrn_poll/', $hub_topic);
104 $self = DI::baseUrl() . '/api/statuses/user_timeline/' . $owner['nickname'] . '.atom';
106 if (!Strings::compareLink($hub_topic, $contact['poll']) && !Strings::compareLink($hub_topic2, $contact['poll']) && !Strings::compareLink($hub_topic, $self)) {
107 Logger::log('Hub topic ' . $hub_topic . ' != ' . $contact['poll']);
108 throw new \Friendica\Network\HTTPException\NotFoundException();
111 // do subscriber verification according to the PuSH protocol
112 $hub_challenge = Strings::getRandomHex(40);
114 $params = http_build_query([
115 'hub.mode' => $subscribe == 1 ? 'subscribe' : 'unsubscribe',
116 'hub.topic' => $hub_topic,
117 'hub.challenge' => $hub_challenge,
118 'hub.verify_token' => $hub_verify_token,
120 // lease time is hard coded to one week (in seconds)
121 // we don't actually enforce the lease time because GNU
122 // Social/StatusNet doesn't honour it (yet)
123 'hub.lease_seconds' => 604800,
126 $hub_callback = rtrim($hub_callback, ' ?&#');
127 $separator = parse_url($hub_callback, PHP_URL_QUERY) === null ? '?' : '&';
129 $fetchResult = Network::fetchUrlFull($hub_callback . $separator . $params);
130 $body = $fetchResult->getBody();
131 $ret = $fetchResult->getReturnCode();
133 // give up if the HTTP return code wasn't a success (2xx)
134 if ($ret < 200 || $ret > 299) {
135 Logger::log("Subscriber verification for $hub_topic at $hub_callback returned $ret, ignoring.");
136 throw new \Friendica\Network\HTTPException\NotFoundException();
139 // check that the correct hub_challenge code was echoed back
140 if (trim($body) !== $hub_challenge) {
141 Logger::log("Subscriber did not echo back hub.challenge, ignoring.");
142 Logger::log("\"$hub_challenge\" != \"".trim($body)."\"");
143 throw new \Friendica\Network\HTTPException\NotFoundException();
146 PushSubscriber::renew($owner['uid'], $nick, $subscribe, $hub_callback, $hub_topic, $hub_secret);
148 throw new \Friendica\Network\HTTPException\AcceptedException();