<?php /** * @file mod/dfrn_confirm.php * @brief Module: dfrn_confirm * Purpose: Friendship acceptance for DFRN contacts * * There are two possible entry points and three scenarios. * * 1. A form was submitted by our user approving a friendship that originated elsewhere. * This may also be called from dfrn_request to automatically approve a friendship. * * 2. We may be the target or other side of the conversation to scenario 1, and will * interact with that process on our own user's behalf. * * @see PDF with dfrn specs: https://github.com/friendica/friendica/blob/master/spec/dfrn2.pdf * You also find a graphic which describes the confirmation process at * https://github.com/friendica/friendica/blob/master/spec/dfrn2_contact_confirmation.png */ use Friendica\App; use Friendica\Core\Config; use Friendica\Core\L10n; use Friendica\Core\Logger; use Friendica\Core\Protocol; use Friendica\Core\System; use Friendica\Database\DBA; use Friendica\Model\Contact; use Friendica\Model\Group; use Friendica\Model\User; use Friendica\Network\Probe; use Friendica\Protocol\Diaspora; use Friendica\Protocol\ActivityPub; use Friendica\Util\Crypto; use Friendica\Util\DateTimeFormat; use Friendica\Util\Network; use Friendica\Util\Strings; use Friendica\Util\XML; function dfrn_confirm_post(App $a, $handsfree = null) { $node = null; if (is_array($handsfree)) { /* * We were called directly from dfrn_request due to automatic friend acceptance. * Any $_POST parameters we may require are supplied in the $handsfree array. * */ $node = $handsfree['node']; $a->interactive = false; // notice() becomes a no-op since nobody is there to see it } elseif ($a->argc > 1) { $node = $a->argv[1]; } /* * Main entry point. Scenario 1. Our user received a friend request notification (perhaps * from another site) and clicked 'Approve'. * $POST['source_url'] is not set. If it is, it indicates Scenario 2. * * We may also have been called directly from dfrn_request ($handsfree != null) due to * this being a page type which supports automatic friend acceptance. That is also Scenario 1 * since we are operating on behalf of our registered user to approve a friendship. */ if (empty($_POST['source_url'])) { $uid = defaults($handsfree, 'uid', local_user()); if (!$uid) { notice(L10n::t('Permission denied.') . EOL); return; } $user = DBA::selectFirst('user', [], ['uid' => $uid]); if (!DBA::isResult($user)) { notice(L10n::t('Profile not found.') . EOL); return; } // These data elements may come from either the friend request notification form or $handsfree array. if (is_array($handsfree)) { Logger::log('Confirm in handsfree mode'); $dfrn_id = $handsfree['dfrn_id']; $intro_id = $handsfree['intro_id']; $duplex = $handsfree['duplex']; $cid = 0; $hidden = intval(defaults($handsfree, 'hidden' , 0)); } else { $dfrn_id = Strings::escapeTags(trim(defaults($_POST, 'dfrn_id' , ''))); $intro_id = intval(defaults($_POST, 'intro_id' , 0)); $duplex = intval(defaults($_POST, 'duplex' , 0)); $cid = intval(defaults($_POST, 'contact_id', 0)); $hidden = intval(defaults($_POST, 'hidden' , 0)); } /* * Ensure that dfrn_id has precedence when we go to find the contact record. * We only want to search based on contact id if there is no dfrn_id, * e.g. for OStatus network followers. */ if (strlen($dfrn_id)) { $cid = 0; } Logger::log('Confirming request for dfrn_id (issued) ' . $dfrn_id); if ($cid) { Logger::log('Confirming follower with contact_id: ' . $cid); } /* * The other person will have been issued an ID when they first requested friendship. * Locate their record. At this time, their record will have both pending and blocked set to 1. * There won't be any dfrn_id if this is a network follower, so use the contact_id instead. */ $r = q("SELECT * FROM `contact` WHERE ( (`issued-id` != '' AND `issued-id` = '%s') OR (`id` = %d AND `id` != 0) ) AND `uid` = %d AND `duplex` = 0 LIMIT 1", DBA::escape($dfrn_id), intval($cid), intval($uid) ); if (!DBA::isResult($r)) { Logger::log('Contact not found in DB.'); notice(L10n::t('Contact not found.') . EOL); notice(L10n::t('This may occasionally happen if contact was requested by both persons and it has already been approved.') . EOL); return; } $contact = $r[0]; $contact_id = $contact['id']; $relation = $contact['rel']; $site_pubkey = $contact['site-pubkey']; $dfrn_confirm = $contact['confirm']; $aes_allow = $contact['aes_allow']; $network = ((strlen($contact['issued-id'])) ? Protocol::DFRN : Protocol::OSTATUS); if ($contact['network']) { $network = $contact['network']; } if ($network === Protocol::DFRN) { /* * Generate a key pair for all further communications with this person. * We have a keypair for every contact, and a site key for unknown people. * This provides a means to carry on relationships with other people if * any single key is compromised. It is a robust key. We're much more * worried about key leakage than anybody cracking it. */ $res = Crypto::newKeypair(4096); $private_key = $res['prvkey']; $public_key = $res['pubkey']; // Save the private key. Send them the public key. q("UPDATE `contact` SET `prvkey` = '%s' WHERE `id` = %d AND `uid` = %d", DBA::escape($private_key), intval($contact_id), intval($uid) ); $params = []; /* * Per the DFRN protocol, we will verify both ends by encrypting the dfrn_id with our * site private key (person on the other end can decrypt it with our site public key). * Then encrypt our profile URL with the other person's site public key. They can decrypt * it with their site private key. If the decryption on the other end fails for either * item, it indicates tampering or key failure on at least one site and we will not be * able to provide a secure communication pathway. * * If other site is willing to accept full encryption, (aes_allow is 1 AND we have php5.3 * or later) then we encrypt the personal public key we send them using AES-256-CBC and a * random key which is encrypted with their site public key. */ $src_aes_key = openssl_random_pseudo_bytes(64); $result = ''; openssl_private_encrypt($dfrn_id, $result, $user['prvkey']); $params['dfrn_id'] = bin2hex($result); $params['public_key'] = $public_key; $my_url = System::baseUrl() . '/profile/' . $user['nickname']; openssl_public_encrypt($my_url, $params['source_url'], $site_pubkey); $params['source_url'] = bin2hex($params['source_url']); if ($aes_allow && function_exists('openssl_encrypt')) { openssl_public_encrypt($src_aes_key, $params['aes_key'], $site_pubkey); $params['aes_key'] = bin2hex($params['aes_key']); $params['public_key'] = bin2hex(openssl_encrypt($public_key, 'AES-256-CBC', $src_aes_key)); } $params['dfrn_version'] = DFRN_PROTOCOL_VERSION; if ($duplex == 1) { $params['duplex'] = 1; } if ($user['page-flags'] == User::PAGE_FLAGS_COMMUNITY) { $params['page'] = 1; } if ($user['page-flags'] == User::PAGE_FLAGS_PRVGROUP) { $params['page'] = 2; } Logger::log('Confirm: posting data to ' . $dfrn_confirm . ': ' . print_r($params, true), Logger::DATA); /* * * POST all this stuff to the other site. * Temporarily raise the network timeout to 120 seconds because the default 60 * doesn't always give the other side quite enough time to decrypt everything. * */ $res = Network::post($dfrn_confirm, $params, null, $redirects, 120)->getBody(); Logger::log(' Confirm: received data: ' . $res, Logger::DATA); // Now figure out what they responded. Try to be robust if the remote site is // having difficulty and throwing up errors of some kind. $leading_junk = substr($res, 0, strpos($res, '<?xml')); $res = substr($res, strpos($res, '<?xml')); if (!strlen($res)) { // No XML at all, this exchange is messed up really bad. // We shouldn't proceed, because the xml parser might choke, // and $status is going to be zero, which indicates success. // We can hardly call this a success. notice(L10n::t('Response from remote site was not understood.') . EOL); return; } if (strlen($leading_junk) && Config::get('system', 'debugging')) { // This might be more common. Mixed error text and some XML. // If we're configured for debugging, show the text. Proceed in either case. notice(L10n::t('Unexpected response from remote site: ') . EOL . $leading_junk . EOL); } if (stristr($res, "<status") === false) { // wrong xml! stop here! Logger::log('Unexpected response posting to ' . $dfrn_confirm); notice(L10n::t('Unexpected response from remote site: ') . EOL . htmlspecialchars($res) . EOL); return; } $xml = XML::parseString($res); $status = (int) $xml->status; $message = XML::unescape($xml->message); // human readable text of what may have gone wrong. switch ($status) { case 0: info(L10n::t("Confirmation completed successfully.") . EOL); break; case 1: // birthday paradox - generate new dfrn-id and fall through. $new_dfrn_id = Strings::getRandomHex(); q("UPDATE contact SET `issued-id` = '%s' WHERE `id` = %d AND `uid` = %d", DBA::escape($new_dfrn_id), intval($contact_id), intval($uid) ); case 2: notice(L10n::t("Temporary failure. Please wait and try again.") . EOL); break; case 3: notice(L10n::t("Introduction failed or was revoked.") . EOL); break; } if (strlen($message)) { notice(L10n::t('Remote site reported: ') . $message . EOL); } if (($status == 0) && $intro_id) { $intro = DBA::selectFirst('intro', ['note'], ['id' => $intro_id]); if (DBA::isResult($intro)) { DBA::update('contact', ['reason' => $intro['note']], ['id' => $contact_id]); } // Success. Delete the notification. DBA::delete('intro', ['id' => $intro_id]); } if ($status != 0) { return; } } /* * We have now established a relationship with the other site. * Let's make our own personal copy of their profile photo so we don't have * to always load it from their site. * * We will also update the contact record with the nature and scope of the relationship. */ Contact::updateAvatar($contact['photo'], $uid, $contact_id); Logger::log('dfrn_confirm: confirm - imported photos'); if ($network === Protocol::DFRN) { $new_relation = Contact::FOLLOWER; if (($relation == Contact::SHARING) || ($duplex)) { $new_relation = Contact::FRIEND; } if (($relation == Contact::SHARING) && ($duplex)) { $duplex = 0; } $r = q("UPDATE `contact` SET `rel` = %d, `name-date` = '%s', `uri-date` = '%s', `blocked` = 0, `pending` = 0, `duplex` = %d, `hidden` = %d, `network` = '%s' WHERE `id` = %d ", intval($new_relation), DBA::escape(DateTimeFormat::utcNow()), DBA::escape(DateTimeFormat::utcNow()), intval($duplex), intval($hidden), DBA::escape(Protocol::DFRN), intval($contact_id) ); } else { if ($network == Protocol::ACTIVITYPUB) { ActivityPub\Transmitter::sendContactAccept($contact['url'], $contact['hub-verify'], $uid); // Setting "pending" to true on a bidirectional contact request could create a problem when it isn't accepted on the other side // Then we have got a situation where - although one direction is accepted - the contact still appears as pending. // Possibly we need two different "pending" fields, one for incoming, one for outgoing? // This has to be thought over, but for now this here is a better solution. // $pending = $duplex; $pending = false; } else { $pending = false; } // $network !== Protocol::DFRN $network = defaults($contact, 'network', Protocol::OSTATUS); $arr = Probe::uri($contact['url'], $network); $notify = defaults($contact, 'notify' , $arr['notify']); $poll = defaults($contact, 'poll' , $arr['poll']); $addr = $arr['addr']; $new_relation = $contact['rel']; $writable = $contact['writable']; if (in_array($network, [Protocol::DIASPORA, Protocol::ACTIVITYPUB])) { if ($duplex) { $new_relation = Contact::FRIEND; } else { $new_relation = Contact::FOLLOWER; } if ($new_relation != Contact::FOLLOWER) { $writable = 1; } } DBA::delete('intro', ['id' => $intro_id]); $fields = ['name-date' => DateTimeFormat::utcNow(), 'uri-date' => DateTimeFormat::utcNow(), 'addr' => $addr, 'notify' => $notify, 'poll' => $poll, 'blocked' => false, 'pending' => $pending, 'network' => $network, 'writable' => $writable, 'hidden' => $hidden, 'rel' => $new_relation]; DBA::update('contact', $fields, ['id' => $contact_id]); } if (!DBA::isResult($r)) { notice(L10n::t('Unable to set contact photo.') . EOL); } // reload contact info $contact = DBA::selectFirst('contact', [], ['id' => $contact_id]); if ((isset($new_relation) && $new_relation == Contact::FRIEND)) { if (DBA::isResult($contact) && ($contact['network'] === Protocol::DIASPORA)) { $ret = Diaspora::sendShare($user, $contact); Logger::log('share returns: ' . $ret); } } Group::addMember(User::getDefaultGroup($uid, $contact["network"]), $contact['id']); if ($network == Protocol::ACTIVITYPUB && $duplex) { ActivityPub\Transmitter::sendActivity('Follow', $contact['url'], $uid); } // Let's send our user to the contact editor in case they want to // do anything special with this new friend. if ($handsfree === null) { $a->internalRedirect('contact/' . intval($contact_id)); } else { return; } //NOTREACHED } /* * End of Scenario 1. [Local confirmation of remote friend request]. * * Begin Scenario 2. This is the remote response to the above scenario. * This will take place on the site that originally initiated the friend request. * In the section above where the confirming party makes a POST and * retrieves xml status information, they are communicating with the following code. */ if (!empty($_POST['source_url'])) { // We are processing an external confirmation to an introduction created by our user. $public_key = defaults($_POST, 'public_key', ''); $dfrn_id = hex2bin(defaults($_POST, 'dfrn_id' , '')); $source_url = hex2bin(defaults($_POST, 'source_url', '')); $aes_key = defaults($_POST, 'aes_key' , ''); $duplex = intval(defaults($_POST, 'duplex' , 0)); $page = intval(defaults($_POST, 'page' , 0)); $forum = (($page == 1) ? 1 : 0); $prv = (($page == 2) ? 1 : 0); Logger::log('dfrn_confirm: requestee contacted: ' . $node); Logger::log('dfrn_confirm: request: POST=' . print_r($_POST, true), Logger::DATA); // If $aes_key is set, both of these items require unpacking from the hex transport encoding. if (!empty($aes_key)) { $aes_key = hex2bin($aes_key); $public_key = hex2bin($public_key); } // Find our user's account $user = DBA::selectFirst('user', [], ['nickname' => $node]); if (!DBA::isResult($user)) { $message = L10n::t('No user record found for \'%s\' ', $node); System::xmlExit(3, $message); // failure // NOTREACHED } $my_prvkey = $user['prvkey']; $local_uid = $user['uid']; if (!strstr($my_prvkey, 'PRIVATE KEY')) { $message = L10n::t('Our site encryption key is apparently messed up.'); System::xmlExit(3, $message); } // verify everything $decrypted_source_url = ""; openssl_private_decrypt($source_url, $decrypted_source_url, $my_prvkey); if (!strlen($decrypted_source_url)) { $message = L10n::t('Empty site URL was provided or URL could not be decrypted by us.'); System::xmlExit(3, $message); // NOTREACHED } $contact = DBA::selectFirst('contact', [], ['url' => $decrypted_source_url, 'uid' => $local_uid]); if (!DBA::isResult($contact)) { if (strstr($decrypted_source_url, 'http:')) { $newurl = str_replace('http:', 'https:', $decrypted_source_url); } else { $newurl = str_replace('https:', 'http:', $decrypted_source_url); } $contact = DBA::selectFirst('contact', [], ['url' => $newurl, 'uid' => $local_uid]); if (!DBA::isResult($contact)) { // this is either a bogus confirmation (?) or we deleted the original introduction. $message = L10n::t('Contact record was not found for you on our site.'); System::xmlExit(3, $message); return; // NOTREACHED } } $relation = $contact['rel']; // Decrypt all this stuff we just received $foreign_pubkey = $contact['site-pubkey']; $dfrn_record = $contact['id']; if (!$foreign_pubkey) { $message = L10n::t('Site public key not available in contact record for URL %s.', $decrypted_source_url); System::xmlExit(3, $message); } $decrypted_dfrn_id = ""; openssl_public_decrypt($dfrn_id, $decrypted_dfrn_id, $foreign_pubkey); if (strlen($aes_key)) { $decrypted_aes_key = ""; openssl_private_decrypt($aes_key, $decrypted_aes_key, $my_prvkey); $dfrn_pubkey = openssl_decrypt($public_key, 'AES-256-CBC', $decrypted_aes_key); } else { $dfrn_pubkey = $public_key; } if (DBA::exists('contact', ['dfrn-id' => $decrypted_dfrn_id])) { $message = L10n::t('The ID provided by your system is a duplicate on our system. It should work if you try again.'); System::xmlExit(1, $message); // Birthday paradox - duplicate dfrn-id // NOTREACHED } $r = q("UPDATE `contact` SET `dfrn-id` = '%s', `pubkey` = '%s' WHERE `id` = %d", DBA::escape($decrypted_dfrn_id), DBA::escape($dfrn_pubkey), intval($dfrn_record) ); if (!DBA::isResult($r)) { $message = L10n::t('Unable to set your contact credentials on our system.'); System::xmlExit(3, $message); } // It's possible that the other person also requested friendship. // If it is a duplex relationship, ditch the issued-id if one exists. if ($duplex) { q("UPDATE `contact` SET `issued-id` = '' WHERE `id` = %d", intval($dfrn_record) ); } // We're good but now we have to scrape the profile photo and send notifications. $contact = DBA::selectFirst('contact', ['photo'], ['id' => $dfrn_record]); if (DBA::isResult($contact)) { $photo = $contact['photo']; } else { $photo = System::baseUrl() . '/images/person-300.jpg'; } Contact::updateAvatar($photo, $local_uid, $dfrn_record); Logger::log('dfrn_confirm: request - photos imported'); $new_relation = Contact::SHARING; if (($relation == Contact::FOLLOWER) || ($duplex)) { $new_relation = Contact::FRIEND; } if (($relation == Contact::FOLLOWER) && ($duplex)) { $duplex = 0; } $r = q("UPDATE `contact` SET `rel` = %d, `name-date` = '%s', `uri-date` = '%s', `blocked` = 0, `pending` = 0, `duplex` = %d, `forum` = %d, `prv` = %d, `network` = '%s' WHERE `id` = %d ", intval($new_relation), DBA::escape(DateTimeFormat::utcNow()), DBA::escape(DateTimeFormat::utcNow()), intval($duplex), intval($forum), intval($prv), DBA::escape(Protocol::DFRN), intval($dfrn_record) ); if (!DBA::isResult($r)) { // indicates schema is messed up or total db failure $message = L10n::t('Unable to update your contact profile details on our system'); System::xmlExit(3, $message); } // Otherwise everything seems to have worked and we are almost done. Yay! // Send an email notification Logger::log('dfrn_confirm: request: info updated'); $combined = null; $r = q("SELECT `contact`.*, `user`.* FROM `contact` LEFT JOIN `user` ON `contact`.`uid` = `user`.`uid` WHERE `contact`.`id` = %d LIMIT 1", intval($dfrn_record) ); if (DBA::isResult($r)) { $combined = $r[0]; if ($combined['notify-flags'] & NOTIFY_CONFIRM) { $mutual = ($new_relation == Contact::FRIEND); notification([ 'type' => NOTIFY_CONFIRM, 'notify_flags' => $combined['notify-flags'], 'language' => $combined['language'], 'to_name' => $combined['username'], 'to_email' => $combined['email'], 'uid' => $combined['uid'], 'link' => System::baseUrl() . '/contact/' . $dfrn_record, 'source_name' => ((strlen(stripslashes($combined['name']))) ? stripslashes($combined['name']) : L10n::t('[Name Withheld]')), 'source_link' => $combined['url'], 'source_photo' => $combined['photo'], 'verb' => ($mutual?ACTIVITY_FRIEND:ACTIVITY_FOLLOW), 'otype' => 'intro' ]); } } System::xmlExit(0); // Success return; // NOTREACHED ////////////////////// End of this scenario /////////////////////////////////////////////// } // somebody arrived here by mistake or they are fishing. Send them to the homepage. $a->internalRedirect(); // NOTREACHED }