<?php use Friendica\App; use Friendica\Core\Config; use Friendica\Core\System; use Friendica\Database\DBA; use Friendica\Model\PushSubscriber; use Friendica\Util\Network; function post_var($name) { return (x($_POST, $name)) ? notags(trim($_POST[$name])) : ''; } function pubsubhubbub_init(App $a) { // PuSH subscription must be considered "public" so just block it // if public access isn't enabled. if (Config::get('system', 'block_public')) { System::httpExit(403); } // Subscription request from subscriber // https://pubsubhubbub.googlecode.com/git/pubsubhubbub-core-0.4.html#anchor4 // Example from GNU Social: // [hub_mode] => subscribe // [hub_callback] => http://status.local/main/push/callback/1 // [hub_verify] => sync // [hub_verify_token] => af11... // [hub_secret] => af11... // [hub_topic] => http://friendica.local/dfrn_poll/sazius if ($_SERVER['REQUEST_METHOD'] === 'POST') { $hub_mode = post_var('hub_mode'); $hub_callback = post_var('hub_callback'); $hub_verify = post_var('hub_verify'); $hub_verify_token = post_var('hub_verify_token'); $hub_secret = post_var('hub_secret'); $hub_topic = post_var('hub_topic'); // check for valid hub_mode if ($hub_mode === 'subscribe') { $subscribe = 1; } elseif ($hub_mode === 'unsubscribe') { $subscribe = 0; } else { logger("Invalid hub_mode=$hub_mode, ignoring."); System::httpExit(404); } logger("$hub_mode request from " . $_SERVER['REMOTE_ADDR']); // get the nick name from the topic, a bit hacky but needed as a fallback $nick = substr(strrchr($hub_topic, "/"), 1); // Normally the url should now contain the nick name as last part of the url if ($a->argc > 1) { $nick = $a->argv[1]; } if (!$nick) { logger('Bad hub_topic=$hub_topic, ignoring.'); System::httpExit(404); } // fetch user from database given the nickname $condition = ['nickname' => $nick, 'account_expired' => false, 'account_removed' => false]; $owner = DBA::selectFirst('user', ['uid', 'hidewall'], $condition); if (!DBA::isResult($owner)) { logger('Local account not found: ' . $nick . ' - topic: ' . $hub_topic . ' - callback: ' . $hub_callback); System::httpExit(404); } // abort if user's wall is supposed to be private if ($owner['hidewall']) { logger('Local user ' . $nick . 'has chosen to hide wall, ignoring.'); System::httpExit(403); } // get corresponding row from contact table $condition = ['uid' => $owner['uid'], 'blocked' => false, 'pending' => false, 'self' => true]; $contact = DBA::selectFirst('contact', ['poll'], $condition); if (!DBA::isResult($contact)) { logger('Self contact for user ' . $owner['uid'] . ' not found.'); System::httpExit(404); } // sanity check that topic URLs are the same $hub_topic2 = str_replace('/feed/', '/dfrn_poll/', $hub_topic); if (!link_compare($hub_topic, $contact['poll']) && !link_compare($hub_topic2, $contact['poll'])) { logger('Hub topic ' . $hub_topic . ' != ' . $contact['poll']); System::httpExit(404); } // do subscriber verification according to the PuSH protocol $hub_challenge = random_string(40); $params = 'hub.mode=' . ($subscribe == 1 ? 'subscribe' : 'unsubscribe') . '&hub.topic=' . urlencode($hub_topic) . '&hub.challenge=' . $hub_challenge . '&hub.lease_seconds=604800' . '&hub.verify_token=' . $hub_verify_token; // lease time is hard coded to one week (in seconds) // we don't actually enforce the lease time because GNU // Social/StatusNet doesn't honour it (yet) $fetchResult = Network::fetchUrlFull($hub_callback . "?" . $params); $body = $fetchResult->getBody(); $ret = $fetchResult->getReturnCode(); // give up if the HTTP return code wasn't a success (2xx) if ($ret < 200 || $ret > 299) { logger("Subscriber verification for $hub_topic at $hub_callback returned $ret, ignoring."); System::httpExit(404); } // check that the correct hub_challenge code was echoed back if (trim($body) !== $hub_challenge) { logger("Subscriber did not echo back hub.challenge, ignoring."); logger("\"$hub_challenge\" != \"".trim($body)."\""); System::httpExit(404); } PushSubscriber::renew($owner['uid'], $nick, $subscribe, $hub_callback, $hub_topic, $hub_secret); System::httpExit(202); } killme(); }