Add new OStatus\Salmon module class

- Add module instanciation in Module\DFRN\Notify

src/Module/DFRN/Notify.php

@@ -21,23 +21,40 @@
 
 namespace Friendica\Module\DFRN;
 
+use Friendica\App;
 use Friendica\BaseModule;
+use Friendica\Core\L10n;
 use Friendica\Core\Logger;
 use Friendica\Core\System;
+use Friendica\Database\Database;
 use Friendica\DI;
 use Friendica\Model\Contact;
 use Friendica\Model\Conversation;
 use Friendica\Model\User;
+use Friendica\Module\OStatus\Salmon;
+use Friendica\Module\Response;
 use Friendica\Protocol\DFRN;
 use Friendica\Protocol\Diaspora;
 use Friendica\Util\Network;
 use Friendica\Network\HTTPException;
+use Friendica\Util\Profiler;
+use Psr\Log\LoggerInterface;
 
 /**
  * DFRN Notify
  */
 class Notify extends BaseModule
 {
+	/** @var Database */
+	private $database;
+
+	public function __construct(Database $database, L10n $l10n, App\BaseURL $baseUrl, App\Arguments $args, LoggerInterface $logger, Profiler $profiler, Response $response, array $server, array $parameters = [])
+	{
+		parent::__construct($l10n, $baseUrl, $args, $logger, $profiler, $response, $server, $parameters);
+
+		$this->database = $database;
+	}
+
 	protected function post(array $request = [])
 	{
 		$postdata = Network::postdata();
@@ -54,8 +71,17 @@ class Notify extends BaseModule
 			}
 			$this->dispatchPrivate($user, $postdata);
 		} elseif (!$this->dispatchPublic($postdata)) {
-			require_once 'mod/salmon.php';
-			salmon_post(DI::app(), $postdata);
+			(new Salmon(
+				$this->database,
+				$this->l10n,
+				$this->baseUrl,
+				$this->args,
+				$this->logger,
+				$this->profiler,
+				$this->response,
+				$this->server,
+				$this->parameters
+			))->rawContent($request);
 		}
 	}
 

src/Module/OStatus/Salmon.php

@@ -0,0 +1,220 @@
+<?php
+/**
+ * @copyright Copyright (C) 2010-2022, the Friendica project
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Friendica\Module\OStatus;
+
+use Friendica\App;
+use Friendica\Core\L10n;
+use Friendica\Core\Protocol;
+use Friendica\Database\Database;
+use Friendica\Model\GServer;
+use Friendica\Model\Post;
+use Friendica\Module\Response;
+use Friendica\Protocol\ActivityNamespace;
+use Friendica\Protocol\OStatus;
+use Friendica\Util\Crypto;
+use Friendica\Util\Network;
+use Friendica\Network\HTTPException;
+use Friendica\Protocol\Salmon as SalmonProtocol;
+use Friendica\Util\Profiler;
+use Friendica\Util\Strings;
+use Psr\Log\LoggerInterface;
+
+/**
+ * Technical endpoint for the Salmon protocol
+ */
+class Salmon extends \Friendica\BaseModule
+{
+	/** @var Database */
+	private $database;
+
+	public function __construct(Database $database, L10n $l10n, App\BaseURL $baseUrl, App\Arguments $args, LoggerInterface $logger, Profiler $profiler, Response $response, array $server, array $parameters = [])
+	{
+		parent::__construct($l10n, $baseUrl, $args, $logger, $profiler, $response, $server, $parameters);
+
+		$this->database = $database;
+	}
+
+	/**
+	 * @param array $request
+	 * @return void
+	 * @throws HTTPException\AcceptedException
+	 * @throws HTTPException\BadRequestException
+	 * @throws HTTPException\InternalServerErrorException
+	 * @throws HTTPException\OKException
+	 * @throws \ImagickException
+	 */
+	protected function rawContent(array $request = [])
+	{
+		$xml = Network::postdata();
+
+		$this->logger->debug('New Salmon', ['nickname' => $this->parameters['nickname'], 'xml' => $xml]);
+
+		// Despite having a route with a mandatory nickname parameter, this method can also be called from
+		// \Friendica\Module\DFRN\Notify->post where the same parameter is optional 🤷‍
+		$nickname = $this->parameters['nickname'] ?? '';
+
+		$importer = $this->database->selectFirst('user', [], ['nickname' => $nickname, 'account_expired' => false, 'account_removed' => false]);
+		if (!$this->database->isResult($importer)) {
+			throw new HTTPException\InternalServerErrorException();
+		}
+
+		// parse the xml
+		$dom = simplexml_load_string($xml, 'SimpleXMLElement', 0, ActivityNamespace::SALMON_ME);
+
+		$base = null;
+
+		// figure out where in the DOM tree our data is hiding
+		if (!empty($dom->provenance->data)) {
+			$base = $dom->provenance;
+		} elseif (!empty($dom->env->data)) {
+			$base = $dom->env;
+		} elseif (!empty($dom->data)) {
+			$base = $dom;
+		}
+
+		if (empty($base)) {
+			$this->logger->notice('unable to locate salmon data in xml');
+			throw new HTTPException\BadRequestException();
+		}
+
+		// Stash the signature away for now. We have to find their key or it won't be good for anything.
+		$signature = Strings::base64UrlDecode($base->sig);
+
+		// unpack the  data
+
+		// strip whitespace so our data element will return to one big base64 blob
+		$data = str_replace([" ", "\t", "\r", "\n"], ["", "", "", ""], $base->data);
+
+		// stash away some other stuff for later
+
+		$type     = $base->data[0]->attributes()->type[0];
+		$keyhash  = $base->sig[0]->attributes()->keyhash[0] ?? '';
+		$encoding = $base->encoding;
+		$alg      = $base->alg;
+
+		// Salmon magic signatures have evolved and there is no way of knowing ahead of time which
+		// flavour we have. We'll try and verify it regardless.
+
+		$stnet_signed_data = $data;
+
+		$signed_data = $data . '.' . Strings::base64UrlEncode($type) . '.' . Strings::base64UrlEncode($encoding) . '.' . Strings::base64UrlEncode($alg);
+
+		$compliant_format = str_replace('=', '', $signed_data);
+
+
+		// decode the data
+		$data = Strings::base64UrlDecode($data);
+
+		$author      = OStatus::salmonAuthor($data, $importer);
+		$author_link = $author["author-link"];
+		if (!$author_link) {
+			$this->logger->notice('Could not retrieve author URI.');
+			throw new HTTPException\BadRequestException();
+		}
+
+		// Once we have the author URI, go to the web and try to find their public key
+
+		$this->logger->notice('Fetching key for ' . $author_link);
+
+		$key = SalmonProtocol::getKey($author_link, $keyhash);
+
+		if (!$key) {
+			$this->logger->notice('Could not retrieve author key.');
+			throw new HTTPException\BadRequestException();
+		}
+
+		$key_info = explode('.', $key);
+
+		$m = Strings::base64UrlDecode($key_info[1]);
+		$e = Strings::base64UrlDecode($key_info[2]);
+
+		$this->logger->info('Key details', ['info' => $key_info]);
+
+		$pubkey = Crypto::meToPem($m, $e);
+
+		// We should have everything we need now. Let's see if it verifies.
+
+		// Try GNU Social format
+		$verify = Crypto::rsaVerify($signed_data, $signature, $pubkey);
+		$mode   = 1;
+
+		if (!$verify) {
+			$this->logger->notice('Message did not verify using protocol. Trying compliant format.');
+			$verify = Crypto::rsaVerify($compliant_format, $signature, $pubkey);
+			$mode   = 2;
+		}
+
+		if (!$verify) {
+			$this->logger->notice('Message did not verify using padding. Trying old statusnet format.');
+			$verify = Crypto::rsaVerify($stnet_signed_data, $signature, $pubkey);
+			$mode   = 3;
+		}
+
+		if (!$verify) {
+			$this->logger->notice('Message did not verify. Discarding.');
+			throw new HTTPException\BadRequestException();
+		}
+
+		$this->logger->notice('Message verified with mode ' . $mode);
+
+
+		/*
+		*
+		* If we reached this point, the message is good. Now let's figure out if the author is allowed to send us stuff.
+		*
+		*/
+
+		$contact = $this->database->selectFirst(
+			'contact',
+			[],
+			[
+				"`network` IN (?, ?)
+		        AND (`nurl` = ? OR `alias` = ? OR `alias` = ?)
+		        AND `uid` = ?",
+                Protocol::OSTATUS, Protocol::DFRN,
+				Strings::normaliseLink($author_link), $author_link, Strings::normaliseLink($author_link),
+				$importer['uid']
+			]
+		);
+
+		if (!empty($contact['gsid'])) {
+			GServer::setProtocol($contact['gsid'], Post\DeliveryData::OSTATUS);
+		}
+
+		// Have we ignored the person?
+		// If so we can not accept this post.
+
+		if (!empty($contact['blocked'])) {
+			$this->logger->notice('Ignoring this author.');
+			throw new HTTPException\AcceptedException();
+		}
+
+		// Placeholder for hub discovery.
+		$hub = '';
+
+		$contact = $contact ?: [];
+
+		OStatus::import($data, $importer, $contact, $hub);
+
+		throw new HTTPException\OKException();
+	}
+}

static/routes.config.php

@@ -553,6 +553,8 @@ return [
 		'/{sub1}/{sub2}/{url}' => [Module\Proxy::class, [R::GET]],
 	],
 
+	'/salmon/{nickname}'       => [Module\OStatus\Salmon::class, [        R::POST]],
+
 	'/search' => [
 		'[/]'                  => [Module\Search\Index::class, [R::GET]],
 		'/acl'                 => [Module\Search\Acl::class,   [R::GET, R::POST]],