<?php /** * @file mod/dfrn_notify.php * @brief The dfrn notify endpoint * @see PDF with dfrn specs: https://github.com/friendica/friendica/blob/master/spec/dfrn2.pdf */ use Friendica\App; use Friendica\Core\Config; use Friendica\Database\DBM; use Friendica\Object\Contact; use Friendica\Protocol\DFRN; require_once 'include/items.php'; require_once 'include/event.php'; function dfrn_notify_post(App $a) { logger(__function__, LOGGER_TRACE); $dfrn_id = ((x($_POST,'dfrn_id')) ? notags(trim($_POST['dfrn_id'])) : ''); $dfrn_version = ((x($_POST,'dfrn_version')) ? (float) $_POST['dfrn_version'] : 2.0); $challenge = ((x($_POST,'challenge')) ? notags(trim($_POST['challenge'])) : ''); $data = ((x($_POST,'data')) ? $_POST['data'] : ''); $key = ((x($_POST,'key')) ? $_POST['key'] : ''); $rino_remote = ((x($_POST,'rino')) ? intval($_POST['rino']) : 0); $dissolve = ((x($_POST,'dissolve')) ? intval($_POST['dissolve']) : 0); $perm = ((x($_POST,'perm')) ? notags(trim($_POST['perm'])) : 'r'); $ssl_policy = ((x($_POST,'ssl_policy')) ? notags(trim($_POST['ssl_policy'])): 'none'); $page = ((x($_POST,'page')) ? intval($_POST['page']) : 0); $forum = (($page == 1) ? 1 : 0); $prv = (($page == 2) ? 1 : 0); $writable = (-1); if ($dfrn_version >= 2.21) { $writable = (($perm === 'rw') ? 1 : 0); } $direction = (-1); if (strpos($dfrn_id, ':') == 1) { $direction = intval(substr($dfrn_id, 0, 1)); $dfrn_id = substr($dfrn_id, 2); } $r = q("SELECT * FROM `challenge` WHERE `dfrn-id` = '%s' AND `challenge` = '%s' LIMIT 1", dbesc($dfrn_id), dbesc($challenge) ); if (! DBM::is_result($r)) { logger('dfrn_notify: could not match challenge to dfrn_id ' . $dfrn_id . ' challenge=' . $challenge); xml_status(3, 'Could not match challenge'); } $r = q("DELETE FROM `challenge` WHERE `dfrn-id` = '%s' AND `challenge` = '%s'", dbesc($dfrn_id), dbesc($challenge) ); // find the local user who owns this relationship. $sql_extra = ''; switch ($direction) { case (-1): $sql_extra = sprintf(" AND ( `issued-id` = '%s' OR `dfrn-id` = '%s' ) ", dbesc($dfrn_id), dbesc($dfrn_id)); break; case 0: $sql_extra = sprintf(" AND `issued-id` = '%s' AND `duplex` = 1 ", dbesc($dfrn_id)); break; case 1: $sql_extra = sprintf(" AND `dfrn-id` = '%s' AND `duplex` = 1 ", dbesc($dfrn_id)); break; default: xml_status(3, 'Invalid direction'); break; // NOTREACHED } /* * be careful - $importer will contain both the contact information for the contact * sending us the post, and also the user information for the person receiving it. * since they are mixed together, it is easy to get them confused. */ $r = q("SELECT `contact`.*, `contact`.`uid` AS `importer_uid`, `contact`.`pubkey` AS `cpubkey`, `contact`.`prvkey` AS `cprvkey`, `contact`.`thumb` AS `thumb`, `contact`.`url` as `url`, `contact`.`name` as `senderName`, `user`.* FROM `contact` LEFT JOIN `user` ON `contact`.`uid` = `user`.`uid` WHERE `contact`.`blocked` = 0 AND `contact`.`pending` = 0 AND `user`.`nickname` = '%s' AND `user`.`account_expired` = 0 AND `user`.`account_removed` = 0 $sql_extra LIMIT 1", dbesc($a->argv[1]) ); if (! DBM::is_result($r)) { logger('dfrn_notify: contact not found for dfrn_id ' . $dfrn_id); xml_status(3, 'Contact not found'); //NOTREACHED } // $importer in this case contains the contact record for the remote contact joined with the user record of our user. $importer = $r[0]; logger("Remote rino version: ".$rino_remote." for ".$importer["url"], LOGGER_DEBUG); if ((($writable != (-1)) && ($writable != $importer['writable'])) || ($importer['forum'] != $forum) || ($importer['prv'] != $prv)) { q("UPDATE `contact` SET `writable` = %d, forum = %d, prv = %d WHERE `id` = %d", intval(($writable == (-1)) ? $importer['writable'] : $writable), intval($forum), intval($prv), intval($importer['id']) ); if ($writable != (-1)) { $importer['writable'] = $writable; } $importer['forum'] = $page; } // if contact's ssl policy changed, update our links fix_contact_ssl_policy($importer,$ssl_policy); logger('dfrn_notify: received notify from ' . $importer['name'] . ' for ' . $importer['username']); logger('dfrn_notify: data: ' . $data, LOGGER_DATA); if ($dissolve == 1) { // Relationship is dissolved permanently Contact::remove($importer['id']); logger('relationship dissolved : ' . $importer['name'] . ' dissolved ' . $importer['username']); xml_status(0, 'relationship dissolved'); } $rino = Config::get('system', 'rino_encrypt'); $rino = intval($rino); logger("Local rino version: " . $rino, LOGGER_DEBUG); if (strlen($key)) { // if local rino is lower than remote rino, abort: should not happen! // but only for $remote_rino > 1, because old code did't send rino version if ($rino_remote_version > 1 && $rino < $rino_remote) { logger("rino version '$rino_remote' is lower than supported '$rino'"); xml_status(0, "rino version '$rino_remote' is lower than supported '$rino'"); } $rawkey = hex2bin(trim($key)); logger('rino: md5 raw key: ' . md5($rawkey)); $final_key = ''; if ($dfrn_version >= 2.1) { if ((($importer['duplex']) && strlen($importer['cprvkey'])) || (! strlen($importer['cpubkey']))) { openssl_private_decrypt($rawkey, $final_key, $importer['cprvkey']); } else { openssl_public_decrypt($rawkey, $final_key, $importer['cpubkey']); } } else { if ((($importer['duplex']) && strlen($importer['cpubkey'])) || (! strlen($importer['cprvkey']))) { openssl_public_decrypt($rawkey, $final_key, $importer['cpubkey']); } else { openssl_private_decrypt($rawkey, $final_key, $importer['cprvkey']); } } #logger('rino: received key : ' . $final_key); switch($rino_remote) { case 0: case 1: /* *we got a key. old code send only the key, without RINO version. * we assume RINO 1 if key and no RINO version */ $data = DFRN::aesDecrypt(hex2bin($data), $final_key); break; case 2: try { $data = \Crypto::decrypt(hex2bin($data), $final_key); } catch (\InvalidCiphertextException $ex) { // VERY IMPORTANT /* * Either: * 1. The ciphertext was modified by the attacker, * 2. The key is wrong, or * 3. $ciphertext is not a valid ciphertext or was corrupted. * Assume the worst. */ logger('The ciphertext has been tampered with!'); xml_status(0, 'The ciphertext has been tampered with!'); } catch (\CryptoTestFailedException $ex) { logger('Cannot safely perform dencryption'); xml_status(0, 'CryptoTestFailed'); } catch (\CannotPerformOperationException $ex) { logger('Cannot safely perform decryption'); xml_status(0, 'Cannot safely perform decryption'); } break; default: logger("rino: invalid sent version '$rino_remote'"); xml_status(0, "Invalid sent version '$rino_remote'"); } logger('rino: decrypted data: ' . $data, LOGGER_DATA); } $ret = DFRN::import($data, $importer); xml_status($ret, 'Processed'); // NOTREACHED } function dfrn_notify_content(App $a) { if(x($_GET,'dfrn_id')) { /* * initial communication from external contact, $direction is their direction. * If this is a duplex communication, ours will be the opposite. */ $dfrn_id = notags(trim($_GET['dfrn_id'])); $dfrn_version = (float) $_GET['dfrn_version']; $rino_remote = ((x($_GET,'rino')) ? intval($_GET['rino']) : 0); $type = ""; $last_update = ""; logger('dfrn_notify: new notification dfrn_id=' . $dfrn_id); $direction = (-1); if(strpos($dfrn_id,':') == 1) { $direction = intval(substr($dfrn_id,0,1)); $dfrn_id = substr($dfrn_id,2); } $hash = random_string(); $status = 0; $r = q("DELETE FROM `challenge` WHERE `expire` < " . intval(time())); $r = q("INSERT INTO `challenge` ( `challenge`, `dfrn-id`, `expire` , `type`, `last_update` ) VALUES( '%s', '%s', %d, '%s', '%s' ) ", dbesc($hash), dbesc($dfrn_id), intval(time() + 90 ), dbesc($type), dbesc($last_update) ); logger('dfrn_notify: challenge=' . $hash, LOGGER_DEBUG); $sql_extra = ''; switch($direction) { case (-1): $sql_extra = sprintf(" AND ( `issued-id` = '%s' OR `dfrn-id` = '%s' ) ", dbesc($dfrn_id), dbesc($dfrn_id)); $my_id = $dfrn_id; break; case 0: $sql_extra = sprintf(" AND `issued-id` = '%s' AND `duplex` = 1 ", dbesc($dfrn_id)); $my_id = '1:' . $dfrn_id; break; case 1: $sql_extra = sprintf(" AND `dfrn-id` = '%s' AND `duplex` = 1 ", dbesc($dfrn_id)); $my_id = '0:' . $dfrn_id; break; default: $status = 1; break; // NOTREACHED } $r = q("SELECT `contact`.*, `user`.`nickname`, `user`.`page-flags` FROM `contact` LEFT JOIN `user` ON `user`.`uid` = `contact`.`uid` WHERE `contact`.`blocked` = 0 AND `contact`.`pending` = 0 AND `user`.`nickname` = '%s' AND `user`.`account_expired` = 0 AND `user`.`account_removed` = 0 $sql_extra LIMIT 1", dbesc($a->argv[1]) ); if (! DBM::is_result($r)) { $status = 1; } logger("Remote rino version: ".$rino_remote." for ".$r[0]["url"], LOGGER_DEBUG); $challenge = ''; $encrypted_id = ''; $id_str = $my_id . '.' . mt_rand(1000,9999); $prv_key = trim($r[0]['prvkey']); $pub_key = trim($r[0]['pubkey']); $dplx = intval($r[0]['duplex']); if ((($dplx) && (strlen($prv_key))) || ((strlen($prv_key)) && (!(strlen($pub_key))))) { openssl_private_encrypt($hash, $challenge, $prv_key); openssl_private_encrypt($id_str, $encrypted_id, $prv_key); } elseif (strlen($pub_key)) { openssl_public_encrypt($hash, $challenge, $pub_key); openssl_public_encrypt($id_str, $encrypted_id, $pub_key); } else { /// @TODO these kind of else-blocks are making the code harder to understand $status = 1; } $challenge = bin2hex($challenge); $encrypted_id = bin2hex($encrypted_id); $rino = Config::get('system', 'rino_encrypt'); $rino = intval($rino); logger("Local rino version: ". $rino, LOGGER_DEBUG); // if requested rino is lower than enabled local rino, lower local rino version // if requested rino is higher than enabled local rino, reply with local rino if ($rino_remote < $rino) { $rino = $rino_remote; } if((($r[0]['rel']) && ($r[0]['rel'] != CONTACT_IS_SHARING)) || ($r[0]['page-flags'] == PAGE_COMMUNITY)) { $perm = 'rw'; } else { $perm = 'r'; } header("Content-type: text/xml"); echo '<?xml version="1.0" encoding="UTF-8"?>' . "\r\n" . '<dfrn_notify>' . "\r\n" . "\t" . '<status>' . $status . '</status>' . "\r\n" . "\t" . '<dfrn_version>' . DFRN_PROTOCOL_VERSION . '</dfrn_version>' . "\r\n" . "\t" . '<rino>' . $rino . '</rino>' . "\r\n" . "\t" . '<perm>' . $perm . '</perm>' . "\r\n" . "\t" . '<dfrn_id>' . $encrypted_id . '</dfrn_id>' . "\r\n" . "\t" . '<challenge>' . $challenge . '</challenge>' . "\r\n" . '</dfrn_notify>' . "\r\n" ; killme(); } }