Return whole file if range request cannot be granted due to encryption

Whenenver range headers are set and encryption is enabled, it is not
possible to automatically fseek() to the proper position.

To avoid returning corrupt/invalid data or causing a decryption error,
the range headers are stripped so that the SabreDAV code in httpGet()
returns the whole file.

Backport of cc8c1d8e0776bda7f4c7c28e11984144a4861df3 from master

1 files changed, 22 insertions, 0 deletions

diff --git a/lib/private/connector/sabre/server.php b/lib/private/connector/sabre/server.php
index aaf4fe85af9..43c3464f1ca 100644
--- a/lib/private/connector/sabre/server.php
+++ b/lib/private/connector/sabre/server.php
@@ -33,6 +33,11 @@ class OC_Connector_Sabre_Server extends Sabre\DAV\Server {
 	 */
 	private $overLoadedUri = null;
 
+	/**
+	 * @var boolean
+	 */
+	private $ignoreRangeHeader = false;
+
 	public function getRequestUri() {
 
 		if (!is_null($this->overLoadedUri)) {
@@ -59,6 +64,23 @@ class OC_Connector_Sabre_Server extends Sabre\DAV\Server {
 		return $result;
 	}
 
+	public function getHTTPRange() {
+		if ($this->ignoreRangeHeader) {
+			return null;
+		}
+		return parent::getHTTPRange();
+	}
+
+	protected function httpGet($uri) {
+		$range = $this->getHTTPRange();
+
+		if (OC_App::isEnabled('files_encryption') && $range) {
+			// encryption does not support range requests
+			$this->ignoreRangeHeader = true;	
+		}
+		return parent::httpGet($uri);
+	}
+
 	/**
 	 * @see \Sabre\DAV\Server
 	 */