Allow devices to register for push notifications

Signed-off-by: Joas Schilling <coding@schilljs.com>

1 files changed, 229 insertions, 0 deletions

diff --git a/lib/Controller/PushController.php b/lib/Controller/PushController.php
new file mode 100644
index 0000000..2e4f4ad
--- /dev/null
+++ b/lib/Controller/PushController.php
@@ -0,0 +1,229 @@
+<?php
+/**
+ * @copyright Copyright (c) 2017 Joas Schilling <coding@schilljs.com>
+ *
+ * @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 <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Notifications\Controller;
+
+use OC\Authentication\Exceptions\InvalidTokenException;
+use OC\Authentication\Token\IProvider;
+use OC\Authentication\Token\IToken;
+use OC\Security\IdentityProof\Crypto;
+use OC\Security\IdentityProof\Manager;
+use OCP\AppFramework\Http;
+use OCP\AppFramework\Http\JSONResponse;
+use OCP\AppFramework\OCSController;
+use OCP\DB\QueryBuilder\IQueryBuilder;
+use OCP\IDBConnection;
+use OCP\IRequest;
+use OCP\ISession;
+use OCP\IUser;
+use OCP\IUserSession;
+
+class PushController extends OCSController {
+
+	/** @var IDBConnection */
+	private $db;
+
+	/** @var ISession */
+	private $session;
+
+	/** @var IUserSession */
+	private $userSession;
+
+	/** @var IProvider */
+	private $tokenProvider;
+
+	/** @var Manager */
+	private $identityProof;
+
+	/** @var Crypto */
+	private $crypto;
+
+	/**
+	 * @param string $appName
+	 * @param IRequest $request
+	 * @param IDBConnection $db
+	 * @param ISession $session
+	 * @param IUserSession $userSession
+	 * @param IProvider $tokenProvider
+	 * @param Manager $identityProof
+	 * @param Crypto $crypto
+	 */
+	public function __construct($appName, IRequest $request, IDBConnection $db, ISession $session, IUserSession $userSession, IProvider $tokenProvider, Manager $identityProof, Crypto $crypto) {
+		parent::__construct($appName, $request);
+
+		$this->db = $db;
+		$this->session = $session;
+		$this->userSession = $userSession;
+		$this->tokenProvider = $tokenProvider;
+		$this->identityProof = $identityProof;
+		$this->crypto = $crypto;
+	}
+
+	/**
+	 * @NoAdminRequired
+	 * @NoCSRFRequired
+	 *
+	 * @param string $pushTokenHash
+	 * @param string $devicePublicKey
+	 * @return JSONResponse
+	 */
+	public function registerDevice($pushTokenHash, $devicePublicKey) {
+		$user = $this->userSession->getUser();
+		if (!$user instanceof IUser) {
+			return new JSONResponse([], Http::STATUS_UNAUTHORIZED);
+		}
+
+		if (!preg_match('/^([a-f0-9]{128})$/', $pushTokenHash)) {
+			return new JSONResponse(['message' => 'Invalid hashed push token'], Http::STATUS_BAD_REQUEST);
+		}
+
+		if (strlen($devicePublicKey) !== 450 ||
+			strpos($devicePublicKey, '-----BEGIN PUBLIC KEY-----') !== 0 ||
+			strpos($devicePublicKey, '-----END PUBLIC KEY-----') !== 426) {
+			return new JSONResponse(['message' => 'Invalid device public key'], Http::STATUS_BAD_REQUEST);
+		}
+
+		$sessionId = $this->session->getId();
+		try {
+			$token = $this->tokenProvider->getToken($sessionId);
+		} catch (InvalidTokenException $e) {
+			return new JSONResponse(['message' => 'Could not identify session token'], Http::STATUS_BAD_REQUEST);
+		}
+
+		$key = $this->identityProof->getKey($user);
+
+		$created = $this->savePushToken($user, $token, $devicePublicKey, $pushTokenHash);
+
+		$encryptedData = $this->crypto->encrypt(json_encode([$user->getCloudId(), $token->getId()]), $user);
+		return new JSONResponse([
+			'publicKey' => $key->getPublic(),
+			'deviceIdentifier' => $encryptedData['message'],
+			'signature' => $encryptedData['signature'],
+		], $created ? Http::STATUS_CREATED : Http::STATUS_OK);
+	}
+
+	/**
+	 * @NoAdminRequired
+	 * @NoCSRFRequired
+	 *
+	 * @param string $devicePublicKey
+	 * @return JSONResponse
+	 */
+	public function removeDevice($devicePublicKey) {
+		$user = $this->userSession->getUser();
+		if (!$user instanceof IUser) {
+			return new JSONResponse([], Http::STATUS_UNAUTHORIZED);
+		}
+
+		if (strlen($devicePublicKey) !== 450 ||
+			strpos($devicePublicKey, '-----BEGIN PUBLIC KEY-----') !== 0 ||
+			strpos($devicePublicKey, '-----END PUBLIC KEY-----') !== 425) {
+			return new JSONResponse(['message' => 'Invalid device public key'], Http::STATUS_BAD_REQUEST);
+		}
+
+		$sessionId = $this->session->getId();
+		try {
+			$token = $this->tokenProvider->getToken($sessionId);
+		} catch (InvalidTokenException $e) {
+			return new JSONResponse(['message' => 'Could not identify session token'], Http::STATUS_BAD_REQUEST);
+		}
+
+		$this->deletePushToken($user, $token, $devicePublicKey);
+		return new JSONResponse();
+	}
+
+	/**
+	 * @param IUser $user
+	 * @param IToken $token
+	 * @param string $devicePublicKey
+	 * @param string $pushTokenHash
+	 * @return bool If the hash was new to the database
+	 */
+	protected function savePushToken(IUser $user, IToken $token, $devicePublicKey, $pushTokenHash) {
+		$query = $this->db->getQueryBuilder();
+		$query->select('pushtokenhash')
+			->from('notifications_pushtokens')
+			->where($query->expr()->eq('uid', $query->createNamedParameter($user->getUID())))
+			->andWhere($query->expr()->eq('token', $query->createNamedParameter($token->getId())))
+			->andWhere($query->expr()->eq('devicepublickey', $query->createNamedParameter($devicePublicKey)));
+		$result = $query->execute();
+		$row = $result->fetch();
+		$result->closeCursor();
+
+		if (!$row) {
+			return $this->insertPushToken($user, $token, $devicePublicKey, $pushTokenHash);
+		} else if ($row['pushtokenhash'] !== $pushTokenHash) {
+			return $this->updatePushToken($user, $token, $devicePublicKey, $pushTokenHash);
+		}
+		return false;
+	}
+
+	/**
+	 * @param IUser $user
+	 * @param IToken $token
+	 * @param string $devicePublicKey
+	 * @param string $pushTokenHash
+	 * @return bool If the entry was created
+	 */
+	protected function insertPushToken(IUser $user, IToken $token, $devicePublicKey, $pushTokenHash) {
+		$query = $this->db->getQueryBuilder();
+		$query->insert('notifications_pushtokens')
+			->values([
+				'uid' => $query->createNamedParameter($user->getUID()),
+				'token' => $query->createNamedParameter($token->getId(), IQueryBuilder::PARAM_INT),
+				'devicepublickey' => $query->createNamedParameter($devicePublicKey),
+				'pushtokenhash' => $query->createNamedParameter($pushTokenHash),
+			]);
+		return $query->execute() > 0;
+	}
+
+	/**
+	 * @param IUser $user
+	 * @param IToken $token
+	 * @param string $devicePublicKey
+	 * @param string $pushTokenHash
+	 * @return bool If the entry was updated
+	 */
+	protected function updatePushToken(IUser $user, IToken $token, $devicePublicKey, $pushTokenHash) {
+		$query = $this->db->getQueryBuilder();
+		$query->update('notifications_pushtokens')
+			->set('pushtokenhash', $query->createNamedParameter($pushTokenHash))
+			->where($query->expr()->eq('uid', $query->createNamedParameter($user->getUID())))
+			->andWhere($query->expr()->eq('token', $query->createNamedParameter($token->getId(), IQueryBuilder::PARAM_INT)))
+			->andWhere($query->expr()->eq('devicepublickey', $query->createNamedParameter($devicePublicKey)));
+		return $query->execute() > 0;
+	}
+
+	/**
+	 * @param IUser $user
+	 * @param IToken $token
+	 * @param string $devicePublicKey
+	 * @return bool If the entry was deleted
+	 */
+	protected function deletePushToken(IUser $user, IToken $token, $devicePublicKey) {
+		$query = $this->db->getQueryBuilder();
+		$query->delete('notifications_pushtokens')
+			->where($query->expr()->eq('uid', $query->createNamedParameter($user->getUID())))
+			->andWhere($query->expr()->eq('token', $query->createNamedParameter($token->getId(), IQueryBuilder::PARAM_INT)))
+			->andWhere($query->expr()->eq('devicepublickey', $query->createNamedParameter($devicePublicKey)));
+		return $query->execute() > 0;
+	}
+}