From c64e0af4fb44b1464ca3433e99b12b729a2084b2 Mon Sep 17 00:00:00 2001
From: Bjoern Schiessle <schiessle@owncloud.com>
Date: Sat, 28 Mar 2015 11:02:26 +0100
Subject: [PATCH] check if recovery key exists and encrypt the file with the
 recovery key if needed

---
 apps/encryption/appinfo/encryption.php    |  5 ++-
 apps/encryption/lib/crypto/encryption.php | 39 ++++++++++++++++++++---
 apps/encryption/lib/keymanager.php        | 20 +++++++++++-
 lib/private/encryption/util.php           | 23 ++++++++++++-
 4 files changed, 80 insertions(+), 7 deletions(-)

diff --git a/apps/encryption/appinfo/encryption.php b/apps/encryption/appinfo/encryption.php
index d97aa07738c..dd8004a4880 100644
--- a/apps/encryption/appinfo/encryption.php
+++ b/apps/encryption/appinfo/encryption.php
@@ -102,7 +102,10 @@ class Encryption extends \OCP\AppFramework\App {
 	public function registerEncryptionModule() {
 		$container = $this->getContainer();
 		$container->registerService('EncryptionModule', function (IAppContainer $c) {
-			return new \OCA\Encryption\Crypto\Encryption($c->query('Crypt'), $c->query('KeyManager'));
+			return new \OCA\Encryption\Crypto\Encryption(
+				$c->query('Crypt'),
+				$c->query('KeyManager'),
+				$c->query('Util'));
 		});
 		$module = $container->query('EncryptionModule');
 		$this->encryptionManager->registerEncryptionModule($module);
diff --git a/apps/encryption/lib/crypto/encryption.php b/apps/encryption/lib/crypto/encryption.php
index da805892eaf..8c00077729e 100644
--- a/apps/encryption/lib/crypto/encryption.php
+++ b/apps/encryption/lib/crypto/encryption.php
@@ -46,9 +46,19 @@ class Encryption implements IEncryptionModule {
 	/** @var boolean */
 	private $isWriteOperation;
 
-	public function __construct(Crypt $crypt, KeyManager $keymanager) {
+	/** @var \OC\Encryption\Util */
+	private $util;
+
+	/**
+	 *
+	 * @param \OCA\Encryption\Crypto\Crypt $crypt
+	 * @param KeyManager $keymanager
+	 * @param \OC\Encryption\Util $util
+	 */
+	public function __construct(Crypt $crypt, KeyManager $keymanager, \OC\Encryption\Util $util) {
 		$this->crypt = $crypt;
 		$this->keymanager = $keymanager;
+		$this->util = $util;
 	}
 
 	/**
@@ -225,9 +235,7 @@ class Encryption implements IEncryptionModule {
 			$publicKeys[$user] = $this->keymanager->getPublicKey($user);
 		}
 
-		if (!empty($accessList['public'])) {
-			$publicKeys[$this->keymanager->getPublicShareKeyId()] = $this->keymanager->getPublicShareKey();
-		}
+		$publicKeys = $this->addSystemKeys($accessList, $publicKeys);
 
 		$encryptedFileKey = $this->crypt->multiKeyEncrypt($fileKey, $publicKeys);
 
@@ -238,6 +246,29 @@ class Encryption implements IEncryptionModule {
 		return true;
 	}
 
+	/**
+	 * add system keys such as the public share key and the recovery key
+	 *
+	 * @param array $accessList
+	 * @param array $publicKeys
+	 * @return array
+	 */
+	public function addSystemKeys(array $accessList, array $publicKeys) {
+		if (!empty($accessList['public'])) {
+			$publicKeys[$this->keymanager->getPublicShareKeyId()] = $this->keymanager->getPublicShareKey();
+		}
+
+		if ($this->keymanager->recoveryKeyExists() &&
+			$this->util->recoveryEnabled($this->user)) {
+
+			$publicKeys[$this->keymanager->getRecoveryKeyId()] = $this->keymanager->getRecoveryKey();
+		}
+
+
+		return $publicKeys;
+	}
+
+
 	/**
 	 * should the file be encrypted or not
 	 *
diff --git a/apps/encryption/lib/keymanager.php b/apps/encryption/lib/keymanager.php
index 44a46458692..ea338f88ea7 100644
--- a/apps/encryption/lib/keymanager.php
+++ b/apps/encryption/lib/keymanager.php
@@ -141,7 +141,25 @@ class KeyManager {
 	 * @return bool
 	 */
 	public function recoveryKeyExists() {
-		return (strlen($this->keyStorage->getSystemUserKey($this->recoveryKeyId)) !== 0);
+		return (!empty($this->keyStorage->getSystemUserKey($this->recoveryKeyId)));
+	}
+
+	/**
+	 * get recovery key
+	 *
+	 * @return string
+	 */
+	public function getRecoveryKey() {
+		return $this->keyStorage->getSystemUserKey($this->recoveryKeyId . '.publicKey');
+	}
+
+	/**
+	 * get recovery key ID
+	 *
+	 * @return string
+	 */
+	public function getRecoveryKeyId() {
+		return $this->recoveryKeyId;
 	}
 
 	/**
diff --git a/lib/private/encryption/util.php b/lib/private/encryption/util.php
index 85e852ec2c9..e3390f155d4 100644
--- a/lib/private/encryption/util.php
+++ b/lib/private/encryption/util.php
@@ -26,6 +26,7 @@ namespace OC\Encryption;
 use OC\Encryption\Exceptions\EncryptionHeaderToLargeException;
 use OC\Encryption\Exceptions\EncryptionHeaderKeyExistsException;
 use OCP\Encryption\IEncryptionModule;
+use OCP\IConfig;
 
 class Util {
 
@@ -58,19 +59,27 @@ class Util {
 	/** @var \OC\User\Manager */
 	protected $userManager;
 
+	/** @var IConfig */
+	protected $config;
+
 	/** @var array paths excluded from encryption */
 	protected $excludedPaths;
 
 	/**
 	 * @param \OC\Files\View $view root view
 	 */
-	public function __construct(\OC\Files\View $view, \OC\User\Manager $userManager) {
+	public function __construct(
+		\OC\Files\View $view,
+		\OC\User\Manager $userManager,
+		IConfig $config) {
+
 		$this->ocHeaderKeys = [
 			self::HEADER_ENCRYPTION_MODULE_KEY
 		];
 
 		$this->view = $view;
 		$this->userManager = $userManager;
+		$this->config = $config;
 
 		$this->excludedPaths[] = 'files_encryption';
 	}
@@ -411,4 +420,16 @@ class Util {
 		return false;
 	}
 
+	/**
+	 * check if recovery key is enabled for user
+	 *
+	 * @param string $uid
+	 * @return boolean
+	 */
+	public function recoveryEnabled($uid) {
+		$enabled = $this->config->getUserValue($uid, 'encryption', 'recovery_enabled', '0');
+
+		return ($enabled === '1') ? true : false;
+	}
+
 }
-- 
2.39.5