3 * @copyright Copyright (C) 2010-2022, the Friendica project
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/>.
22 namespace Friendica\Module\OStatus;
25 use Friendica\Core\L10n;
26 use Friendica\Core\Protocol;
27 use Friendica\Database\Database;
28 use Friendica\Model\GServer;
29 use Friendica\Model\Post;
30 use Friendica\Module\Response;
31 use Friendica\Protocol\ActivityNamespace;
32 use Friendica\Protocol\OStatus;
33 use Friendica\Util\Crypto;
34 use Friendica\Util\Network;
35 use Friendica\Network\HTTPException;
36 use Friendica\Protocol\Salmon as SalmonProtocol;
37 use Friendica\Util\Profiler;
38 use Friendica\Util\Strings;
39 use Psr\Log\LoggerInterface;
42 * Technical endpoint for the Salmon protocol
44 class Salmon extends \Friendica\BaseModule
49 public function __construct(Database $database, L10n $l10n, App\BaseURL $baseUrl, App\Arguments $args, LoggerInterface $logger, Profiler $profiler, Response $response, array $server, array $parameters = [])
51 parent::__construct($l10n, $baseUrl, $args, $logger, $profiler, $response, $server, $parameters);
53 $this->database = $database;
57 * @param array $request
59 * @throws HTTPException\AcceptedException
60 * @throws HTTPException\BadRequestException
61 * @throws HTTPException\InternalServerErrorException
62 * @throws HTTPException\OKException
63 * @throws \ImagickException
65 protected function rawContent(array $request = [])
67 $xml = Network::postdata();
69 $this->logger->debug('New Salmon', ['nickname' => $this->parameters['nickname'], 'xml' => $xml]);
71 // Despite having a route with a mandatory nickname parameter, this method can also be called from
72 // \Friendica\Module\DFRN\Notify->post where the same parameter is optional 🤷
73 $nickname = $this->parameters['nickname'] ?? '';
75 $importer = $this->database->selectFirst('user', [], ['nickname' => $nickname, 'account_expired' => false, 'account_removed' => false]);
76 if (!$this->database->isResult($importer)) {
77 throw new HTTPException\InternalServerErrorException();
81 $dom = simplexml_load_string($xml, 'SimpleXMLElement', 0, ActivityNamespace::SALMON_ME);
85 // figure out where in the DOM tree our data is hiding
86 if (!empty($dom->provenance->data)) {
87 $base = $dom->provenance;
88 } elseif (!empty($dom->env->data)) {
90 } elseif (!empty($dom->data)) {
95 $this->logger->notice('unable to locate salmon data in xml');
96 throw new HTTPException\BadRequestException();
99 // Stash the signature away for now. We have to find their key or it won't be good for anything.
100 $signature = Strings::base64UrlDecode($base->sig);
104 // strip whitespace so our data element will return to one big base64 blob
105 $data = str_replace([" ", "\t", "\r", "\n"], ["", "", "", ""], $base->data);
107 // stash away some other stuff for later
109 $type = $base->data[0]->attributes()->type[0];
110 $keyhash = $base->sig[0]->attributes()->keyhash[0] ?? '';
111 $encoding = $base->encoding;
114 // Salmon magic signatures have evolved and there is no way of knowing ahead of time which
115 // flavour we have. We'll try and verify it regardless.
117 $stnet_signed_data = $data;
119 $signed_data = $data . '.' . Strings::base64UrlEncode($type) . '.' . Strings::base64UrlEncode($encoding) . '.' . Strings::base64UrlEncode($alg);
121 $compliant_format = str_replace('=', '', $signed_data);
125 $data = Strings::base64UrlDecode($data);
127 $author = OStatus::salmonAuthor($data, $importer);
128 $author_link = $author["author-link"];
130 $this->logger->notice('Could not retrieve author URI.');
131 throw new HTTPException\BadRequestException();
134 // Once we have the author URI, go to the web and try to find their public key
136 $this->logger->notice('Fetching key for ' . $author_link);
138 $key = SalmonProtocol::getKey($author_link, $keyhash);
141 $this->logger->notice('Could not retrieve author key.');
142 throw new HTTPException\BadRequestException();
145 $this->logger->info('Key details', ['info' => $key]);
147 $pubkey = SalmonProtocol::magicKeyToPem($key);
149 // We should have everything we need now. Let's see if it verifies.
151 // Try GNU Social format
152 $verify = Crypto::rsaVerify($signed_data, $signature, $pubkey);
156 $this->logger->notice('Message did not verify using protocol. Trying compliant format.');
157 $verify = Crypto::rsaVerify($compliant_format, $signature, $pubkey);
162 $this->logger->notice('Message did not verify using padding. Trying old statusnet format.');
163 $verify = Crypto::rsaVerify($stnet_signed_data, $signature, $pubkey);
168 $this->logger->notice('Message did not verify. Discarding.');
169 throw new HTTPException\BadRequestException();
172 $this->logger->notice('Message verified with mode ' . $mode);
177 * If we reached this point, the message is good. Now let's figure out if the author is allowed to send us stuff.
181 $contact = $this->database->selectFirst(
186 AND (`nurl` = ? OR `alias` = ? OR `alias` = ?)
188 Protocol::OSTATUS, Protocol::DFRN,
189 Strings::normaliseLink($author_link), $author_link, Strings::normaliseLink($author_link),
194 if (!empty($contact['gsid'])) {
195 GServer::setProtocol($contact['gsid'], Post\DeliveryData::OSTATUS);
198 // Have we ignored the person?
199 // If so we can not accept this post.
201 if (!empty($contact['blocked'])) {
202 $this->logger->notice('Ignoring this author.');
203 throw new HTTPException\AcceptedException();
206 // Placeholder for hub discovery.
209 $contact = $contact ?: [];
211 OStatus::import($data, $importer, $contact, $hub);
213 throw new HTTPException\OKException();