<?php
declare(strict_types=1);
// {{{ License
// This file is part of GNU social - https://www.gnu.org/software/social
//
// GNU social 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.
//
// GNU social 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 GNU social. If not, see <http://www.gnu.org/licenses/>.
// }}}
/**
* ActivityPub implementation for GNU social
*
* @package GNUsocial
* @category ActivityPub
* @author Diogo Peralta Cordeiro <@diogo.site>
* @copyright 2018-2019, 2021 Free Software Foundation, Inc http://www.fsf.org
* @license https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
*/
namespace Plugin\ActivityPub;
use App\Core\Event;
use App\Core\HTTPClient;
use App\Core\Log;
use App\Core\Modules\Plugin;
use App\Core\Router\RouteLoader;
use App\Core\Router\Router;
use App\Entity\Activity;
use App\Entity\Actor;
use App\Entity\LocalUser;
use App\Util\Common;
use App\Util\Exception\NoSuchActorException;
use App\Util\Nickname;
use Component\FreeNetwork\Entity\FreeNetworkActorProtocol;
use Component\FreeNetwork\Util\Discovery;
use Exception;
use Plugin\ActivityPub\Controller\Inbox;
use Plugin\ActivityPub\Entity\ActivitypubActor;
use Plugin\ActivityPub\Util\HTTPSignature;
use Plugin\ActivityPub\Util\Model;
use Plugin\ActivityPub\Util\Response\ActorResponse;
use Plugin\ActivityPub\Util\Response\NoteResponse;
use Plugin\ActivityPub\Util\TypeResponse;
use Plugin\ActivityPub\Util\Validator\contentLangModelValidator;
use Plugin\ActivityPub\Util\Validator\manuallyApprovesFollowersModelValidator;
use Symfony\Contracts\HttpClient\Exception\ClientExceptionInterface;
use Symfony\Contracts\HttpClient\Exception\RedirectionExceptionInterface;
use Symfony\Contracts\HttpClient\Exception\ServerExceptionInterface;
use Symfony\Contracts\HttpClient\Exception\TransportExceptionInterface;
use Symfony\Contracts\HttpClient\ResponseInterface;
use XML_XRD;
use XML_XRD_Element_Link;
use function count;
use function is_null;
use const PHP_URL_HOST;
use const PREG_SET_ORDER;
/**
* Adds ActivityPub support to GNU social when enabled
*
* @copyright 2018-2019, 2021 Free Software Foundation, Inc http://www.fsf.org
* @license https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
*/
class ActivityPub extends Plugin
{
// ActivityStreams 2.0 Accept Headers
public static array $accept_headers = [
'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
'application/activity+json',
'application/json',
'application/ld+json',
];
// So that this isn't hardcoded everywhere
public const PUBLIC_TO = [
'https://www.w3.org/ns/activitystreams#Public',
'Public',
'as:Public',
];
public const HTTP_CLIENT_HEADERS = [
'Accept' => 'application/ld+json; profile="https://www.w3.org/ns/activitystreams"',
'User-Agent' => 'GNUsocialBot ' . GNUSOCIAL_VERSION . ' - ' . GNUSOCIAL_PROJECT_URL,
];
public function version(): string
{
return '3.0.0';
}
/**
* This code executes when GNU social creates the page routing, and we hook
* on this event to add our Inbox and Outbox handler for ActivityPub.
*
* @param RouteLoader $r the router that was initialized
*/
public function onAddRoute(RouteLoader $r): bool
{
$r->connect(
'activitypub_inbox',
'/inbox.json',
[Inbox::class, 'handle'],
options: ['accept' => self::$accept_headers, 'format' => self::$accept_headers[0]],
);
$r->connect(
'activitypub_actor_inbox',
'/actor/{gsactor_id<\d+>}/inbox.json',
[Inbox::class, 'handle'],
options: ['accept' => self::$accept_headers, 'format' => self::$accept_headers[0]],
);
$r->connect(
'activitypub_actor_outbox',
'/actor/{gsactor_id<\d+>}/outbox.json',
[Inbox::class, 'handle'],
options: ['accept' => self::$accept_headers, 'format' => self::$accept_headers[0]],
);
return Event::next;
}
/**
* Fill Actor->getUrl() calls with correct URL coming from ActivityPub
*
* @param Actor $actor
* @param int $type
* @param string|null $url
* @return bool
*/
public function onStartGetActorUrl(Actor $actor, int $type, ?string &$url): bool
{
if (
// Is remote?
!$actor->getIsLocal()
// Is in ActivityPub?
&& !is_null($ap_actor = ActivitypubActor::getWithPK(['actor_id' => $actor->getId()]))
// We can only provide a full URL (anything else wouldn't make sense)
&& $type === Router::ABSOLUTE_URL
) {
$url = $ap_actor->getUri();
return Event::stop;
}
return Event::next;
}
/**
* Overload core endpoints to make resources available in ActivityStreams 2.0
*
* @throws Exception
*/
public function onControllerResponseInFormat(string $route, array $accept_header, array $vars, ?TypeResponse &$response = null): bool
{
if (count(array_intersect(self::$accept_headers, $accept_header)) === 0) {
return Event::next;
}
switch ($route) {
case 'actor_view_id':
case 'actor_view_nickname':
$response = ActorResponse::handle($vars['actor']);
return Event::stop;
case 'note_view':
$response = NoteResponse::handle($vars['note']);
return Event::stop;
default:
if (Event::handle('ActivityPubActivityStreamsTwoResponse', [$route, $vars, &$response]) === Event::stop) {
return Event::stop;
}
return Event::next;
}
}
/**
* Add ActivityStreams 2 Extensions
*
* @param string $type_name
* @param array $validators
* @return bool
*/
public function onActivityPubValidateActivityStreamsTwoData(string $type_name, array &$validators): bool
{
switch ($type_name) {
case 'Person':
$validators['manuallyApprovesFollowers'] = manuallyApprovesFollowersModelValidator::class;
break;
case 'Note':
$validators['contentLang'] = contentLangModelValidator::class;
break;
}
return Event::next;
}
// FreeNetworkComponent Events
/**
* Let FreeNetwork Component know we exist and which class to use to call the freeNetworkDistribute method
*
* @param array $protocols
* @return bool
*/
public function onAddFreeNetworkProtocol(array &$protocols): bool
{
$protocols[] = '\Plugin\ActivityPub\ActivityPub';
return Event::next;
}
/**
* The FreeNetwork component will call this function to distribute this instance's activities
*
* @param Actor $sender
* @param Activity $activity
* @param array $targets
* @param string|null $reason
* @param array $delivered
* @return bool
* @throws ClientExceptionInterface
* @throws RedirectionExceptionInterface
* @throws ServerExceptionInterface
* @throws TransportExceptionInterface
*/
public static function freeNetworkDistribute(Actor $sender, Activity $activity, array $targets, ?string $reason = null, array &$delivered = []): bool
{
$to_addr = [];
foreach ($targets as $actor) {
if (FreeNetworkActorProtocol::canIActor('activitypub', $actor->getId())) {
if (is_null($ap_target = ActivitypubActor::getWithPK(['actor_id' => $actor->getId()]))) {
continue;
}
$to_addr[$ap_target->getInboxSharedUri() ?? $ap_target->getInboxUri()][] = $actor;
} else {
return Event::next;
}
}
$errors = [];
//$to_failed = [];
foreach ($to_addr as $inbox => $dummy) {
try {
$res = self::postman($sender, Model::toJson($activity), $inbox);
// accumulate errors for later use, if needed
$status_code = $res->getStatusCode();
if (!($status_code === 200 || $status_code === 202 || $status_code === 409)) {
$res_body = json_decode($res->getContent(), true);
$errors[] = $res_body['error'] ?? 'An unknown error occurred.';
//$to_failed[$inbox] = $activity;
} else {
array_push($delivered, ...$dummy);
foreach ($dummy as $actor) {
FreeNetworkActorProtocol::protocolSucceeded(
'activitypub',
$actor,
Discovery::normalize($actor->getNickname() . '@' . parse_url($inbox, PHP_URL_HOST)),
);
}
}
} catch (Exception $e) {
Log::error('ActivityPub @ freeNetworkDistribute: ' . $e->getMessage());
//$to_failed[$inbox] = $activity;
}
}
if (!empty($errors)) {
Log::error(sizeof($errors) . ' instance/s failed to handle the delete_profile activity!');
return false;
}
return true;
}
/**
* Internal tool to sign and send activities out
*
* @param Actor $sender
* @param string $json_activity
* @param string $inbox
* @param string $method
* @return ResponseInterface
* @throws Exception
*/
private static function postman(Actor $sender, string $json_activity, string $inbox, string $method = 'post'): ResponseInterface
{
Log::debug('ActivityPub Postman: Delivering ' . $json_activity . ' to ' . $inbox);
$headers = HTTPSignature::sign($sender, $inbox, $json_activity);
Log::debug('ActivityPub Postman: Delivery headers were: ' . print_r($headers, true));
$response = HTTPClient::$method($inbox, ['headers' => $headers, 'body' => $json_activity]);
Log::debug('ActivityPub Postman: Delivery result with status code ' . $response->getStatusCode() . ': ' . $response->getContent());
return $response;
}
// WebFinger Events
/**
* Add activity+json mimetype to WebFinger
*
* @param XML_XRD $xrd
* @param Actor $object
* @return bool
*/
public function onEndWebFingerProfileLinks(XML_XRD $xrd, Actor $object): bool
{
if ($object->isPerson()) {
$link = new XML_XRD_Element_Link(
rel: 'self',
href: $object->getUri(Router::ABSOLUTE_URL),//Router::url('actor_view_id', ['id' => $object->getId()], Router::ABSOLUTE_URL),
type: 'application/activity+json',
);
$xrd->links[] = clone $link;
}
return Event::next;
}
/**
* When FreeNetwork component asks us to help with identifying Actors from XRDs
*
* @param XML_XRD $xrd
* @param Actor|null $actor
* @return bool
*/
public function onFreeNetworkFoundXrd(XML_XRD $xrd, ?Actor &$actor = null): bool
{
$addr = null;
foreach ($xrd->aliases as $alias) {
if (Discovery::isAcct($alias)) {
$addr = Discovery::normalize($alias);
}
}
if (is_null($addr)) {
return Event::next;
} else {
if (!FreeNetworkActorProtocol::canIAddr('activitypub', $addr)) {
return Event::next;
}
}
try {
$ap_actor = ActivitypubActor::fromXrd($addr, $xrd);
$actor = Actor::getById($ap_actor->getActorId());
FreeNetworkActorProtocol::protocolSucceeded('activitypub', $actor, $addr);
return Event::stop;
} catch (Exception $e) {
Log::error('ActivityPub Actor from URL Mention check failed: ' . $e->getMessage());
return Event::next;
}
}
// Discovery Events
/**
* When FreeNetwork component asks us to help with identifying Actors from URIs
*
* @param string $target
* @param Actor|null $actor
* @return bool
*/
public function onFreeNetworkFindMentions(string $target, ?Actor &$actor = null): bool
{
try {
if (FreeNetworkActorProtocol::canIAddr('activitypub', $addr = Discovery::normalize($target))) {
$ap_actor = ActivitypubActor::getByAddr($addr);
$actor = Actor::getById($ap_actor->getActorId());
FreeNetworkActorProtocol::protocolSucceeded('activitypub', $actor->getId(), $addr);
return Event::stop;
} else {
return Event::next;
}
} catch (Exception $e) {
Log::error('ActivityPub Webfinger Mention check failed: ' . $e->getMessage());
return Event::next;
}
}
/**
* Get an Actor from ActivityPub URI, if it doesn't exist, attempt to fetch it
* This should only be necessary internally.
*
* @param string $resource
* @return Actor got from URI
* @throws NoSuchActorException
*/
public static function getActorByUri(string $resource): Actor
{
// Try local
if (Common::isValidHttpUrl($resource)) {
// This means $resource is a valid url
$resource_parts = parse_url($resource);
// TODO: Use URLMatcher
if ($resource_parts['host'] === $_ENV['SOCIAL_DOMAIN']) { // XXX: Common::config('site', 'server')) {
$str = $resource_parts['path'];
// actor_view_nickname
$renick = '/\/@(' . Nickname::DISPLAY_FMT . ')\/?/m';
// actor_view_id
$reuri = '/\/actor\/(\d+)\/?/m';
if (preg_match_all($renick, $str, $matches, PREG_SET_ORDER, 0) === 1) {
return LocalUser::getWithPK(['nickname' => $matches[0][1]])->getActor();
} elseif (preg_match_all($reuri, $str, $matches, PREG_SET_ORDER, 0) === 1) {
return Actor::getById((int)$matches[0][1]);
}
}
}
// Try remote
$aprofile = ActivitypubActor::getByAddr($resource);
if ($aprofile instanceof ActivitypubActor) {
return Actor::getById($aprofile->getActorId());
} else {
throw new NoSuchActorException("From URI: {$resource}");
}
}
}