1 files changed, 275 insertions, 0 deletions
diff --git a/lib/private/Federation/CloudIdManager.php b/lib/private/Federation/CloudIdManager.php
new file mode 100644
index 00000000000..c599d9046a6
--- /dev/null
+++ b/lib/private/Federation/CloudIdManager.php
@@ -0,0 +1,275 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2017 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+namespace OC\Federation;
+
+use OCA\DAV\Events\CardUpdatedEvent;
+use OCP\Contacts\IManager;
+use OCP\EventDispatcher\Event;
+use OCP\EventDispatcher\IEventDispatcher;
+use OCP\Federation\ICloudId;
+use OCP\Federation\ICloudIdManager;
+use OCP\Federation\ICloudIdResolver;
+use OCP\ICache;
+use OCP\ICacheFactory;
+use OCP\IURLGenerator;
+use OCP\IUserManager;
+use OCP\User\Events\UserChangedEvent;
+
+class CloudIdManager implements ICloudIdManager {
+	private ICache $memCache;
+	private ICache $displayNameCache;
+	private array $cache = [];
+	/** @var ICloudIdResolver[] */
+	private array $cloudIdResolvers = [];
+
+	public function __construct(
+		ICacheFactory $cacheFactory,
+		IEventDispatcher $eventDispatcher,
+		private IManager $contactsManager,
+		private IURLGenerator $urlGenerator,
+		private IUserManager $userManager,
+	) {
+		$this->memCache = $cacheFactory->createDistributed('cloud_id_');
+		$this->displayNameCache = $cacheFactory->createDistributed('cloudid_name_');
+		$eventDispatcher->addListener(UserChangedEvent::class, [$this, 'handleUserEvent']);
+		$eventDispatcher->addListener(CardUpdatedEvent::class, [$this, 'handleCardEvent']);
+	}
+
+	public function handleUserEvent(Event $event): void {
+		if ($event instanceof UserChangedEvent && $event->getFeature() === 'displayName') {
+			$userId = $event->getUser()->getUID();
+			$key = $userId . '@local';
+			unset($this->cache[$key]);
+			$this->memCache->remove($key);
+		}
+	}
+
+	public function handleCardEvent(Event $event): void {
+		if ($event instanceof CardUpdatedEvent) {
+			$data = $event->getCardData()['carddata'];
+			foreach (explode("\r\n", $data) as $line) {
+				if (str_starts_with($line, 'CLOUD;')) {
+					$parts = explode(':', $line, 2);
+					if (isset($parts[1])) {
+						$key = $parts[1];
+						unset($this->cache[$key]);
+						$this->memCache->remove($key);
+					}
+				}
+			}
+		}
+	}
+
+	/**
+	 * @param string $cloudId
+	 * @return ICloudId
+	 * @throws \InvalidArgumentException
+	 */
+	public function resolveCloudId(string $cloudId): ICloudId {
+		// TODO magic here to get the url and user instead of just splitting on @
+
+		foreach ($this->cloudIdResolvers as $resolver) {
+			if ($resolver->isValidCloudId($cloudId)) {
+				return $resolver->resolveCloudId($cloudId);
+			}
+		}
+
+		if (!$this->isValidCloudId($cloudId)) {
+			throw new \InvalidArgumentException('Invalid cloud id');
+		}
+
+		// Find the first character that is not allowed in user names
+		$id = $this->stripShareLinkFragments($cloudId);
+		$posSlash = strpos($id, '/');
+		$posColon = strpos($id, ':');
+
+		if ($posSlash === false && $posColon === false) {
+			$invalidPos = \strlen($id);
+		} elseif ($posSlash === false) {
+			$invalidPos = $posColon;
+		} elseif ($posColon === false) {
+			$invalidPos = $posSlash;
+		} else {
+			$invalidPos = min($posSlash, $posColon);
+		}
+
+		$lastValidAtPos = strrpos($id, '@', $invalidPos - strlen($id));
+
+		if ($lastValidAtPos !== false) {
+			$user = substr($id, 0, $lastValidAtPos);
+			$remote = substr($id, $lastValidAtPos + 1);
+
+			// We accept slightly more chars when working with federationId than with a local userId.
+			// We remove those eventual chars from the UserId before using
+			// the IUserManager API to confirm its format.
+			$this->userManager->validateUserId(str_replace('=', '-', $user));
+
+			if (!empty($user) && !empty($remote)) {
+				$remote = $this->ensureDefaultProtocol($remote);
+				return new CloudId($id, $user, $remote, null);
+			}
+		}
+		throw new \InvalidArgumentException('Invalid cloud id');
+	}
+
+	public function getDisplayNameFromContact(string $cloudId): ?string {
+		$cachedName = $this->displayNameCache->get($cloudId);
+		if ($cachedName !== null) {
+			if ($cachedName === $cloudId) {
+				return null;
+			}
+			return $cachedName;
+		}
+
+		$addressBookEntries = $this->contactsManager->search($cloudId, ['CLOUD'], [
+			'limit' => 1,
+			'enumeration' => false,
+			'fullmatch' => false,
+			'strict_search' => true,
+		]);
+		foreach ($addressBookEntries as $entry) {
+			if (isset($entry['CLOUD'])) {
+				foreach ($entry['CLOUD'] as $cloudID) {
+					if ($cloudID === $cloudId) {
+						// Warning, if user decides to make their full name local only,
+						// no FN is found on federated servers
+						if (isset($entry['FN'])) {
+							$this->displayNameCache->set($cloudId, $entry['FN'], 15 * 60);
+							return $entry['FN'];
+						} else {
+							$this->displayNameCache->set($cloudId, $cloudId, 15 * 60);
+							return null;
+						}
+					}
+				}
+			}
+		}
+		$this->displayNameCache->set($cloudId, $cloudId, 15 * 60);
+		return null;
+	}
+
+	/**
+	 * @param string $user
+	 * @param string|null $remote
+	 * @return CloudId
+	 */
+	public function getCloudId(string $user, ?string $remote): ICloudId {
+		$isLocal = $remote === null;
+		if ($isLocal) {
+			$remote = rtrim($this->urlGenerator->getAbsoluteURL('/'), '/');
+		}
+
+		// note that for remote id's we don't strip the protocol for the remote we use to construct the CloudId
+		// this way if a user has an explicit non-https cloud id this will be preserved
+		// we do still use the version without protocol for looking up the display name
+		$remote = $this->stripShareLinkFragments($remote);
+		$host = $this->removeProtocolFromUrl($remote);
+		$remote = $this->ensureDefaultProtocol($remote);
+
+		$key = $user . '@' . ($isLocal ? 'local' : $host);
+		$cached = $this->cache[$key] ?? $this->memCache->get($key);
+		if ($cached) {
+			$this->cache[$key] = $cached; // put items from memcache into local cache
+			return new CloudId($cached['id'], $cached['user'], $cached['remote'], $cached['displayName']);
+		}
+
+		if ($isLocal) {
+			$localUser = $this->userManager->get($user);
+			$displayName = $localUser ? $localUser->getDisplayName() : '';
+		} else {
+			$displayName = null;
+		}
+
+		// For the visible cloudID we only strip away https
+		$id = $user . '@' . $this->removeProtocolFromUrl($remote, true);
+
+		$data = [
+			'id' => $id,
+			'user' => $user,
+			'remote' => $remote,
+			'displayName' => $displayName,
+		];
+		$this->cache[$key] = $data;
+		$this->memCache->set($key, $data, 15 * 60);
+		return new CloudId($id, $user, $remote, $displayName);
+	}
+
+	/**
+	 * @param string $url
+	 * @return string
+	 */
+	public function removeProtocolFromUrl(string $url, bool $httpsOnly = false): string {
+		if (str_starts_with($url, 'https://')) {
+			return substr($url, 8);
+		}
+		if (!$httpsOnly && str_starts_with($url, 'http://')) {
+			return substr($url, 7);
+		}
+
+		return $url;
+	}
+
+	protected function ensureDefaultProtocol(string $remote): string {
+		if (!str_contains($remote, '://')) {
+			$remote = 'https://' . $remote;
+		}
+
+		return $remote;
+	}
+
+	/**
+	 * Strips away a potential file names and trailing slashes:
+	 * - http://localhost
+	 * - http://localhost/
+	 * - http://localhost/index.php
+	 * - http://localhost/index.php/s/{shareToken}
+	 *
+	 * all return: http://localhost
+	 *
+	 * @param string $remote
+	 * @return string
+	 */
+	protected function stripShareLinkFragments(string $remote): string {
+		$remote = str_replace('\\', '/', $remote);
+		if ($fileNamePosition = strpos($remote, '/index.php')) {
+			$remote = substr($remote, 0, $fileNamePosition);
+		}
+		$remote = rtrim($remote, '/');
+
+		return $remote;
+	}
+
+	/**
+	 * @param string $cloudId
+	 * @return bool
+	 */
+	public function isValidCloudId(string $cloudId): bool {
+		foreach ($this->cloudIdResolvers as $resolver) {
+			if ($resolver->isValidCloudId($cloudId)) {
+				return true;
+			}
+		}
+
+		return strpos($cloudId, '@') !== false;
+	}
+
+	public function createCloudId(string $id, string $user, string $remote, ?string $displayName = null): ICloudId {
+		return new CloudId($id, $user, $remote, $displayName);
+	}
+
+	public function registerCloudIdResolver(ICloudIdResolver $resolver): void {
+		array_unshift($this->cloudIdResolvers, $resolver);
+	}
+
+	public function unregisterCloudIdResolver(ICloudIdResolver $resolver): void {
+		if (($key = array_search($resolver, $this->cloudIdResolvers)) !== false) {
+			array_splice($this->cloudIdResolvers, $key, 1);
+		}
+	}
+}