Chunking NG: SHA1 checksumming of whole file #11811

This is for owncloud/client#5102 (comment)

apps/dav/lib/Capabilities.php

@@ -31,6 +31,10 @@ public function getCapabilities() {
 			'dav' => [
 				'chunking' => '1.0',
 			]
+			,
+			'checksums' => [
+				'supportedTypes' => ['SHA1']
+			]
 		];
 	}
 }

apps/dav/lib/Connector/Sabre/File.php

@@ -140,6 +140,18 @@ public function put($data) {
 				throw new Exception('Error while copying file to target location (copied bytes: ' . $count . ', expected filesize: ' . $expected . ' )');
 			}
 
+			if (substr( stream_get_meta_data($data)['uri'], 0, 11 ) == "assembly://") {
+				$assemblyStream = (stream_get_meta_data($data)['wrapper_data']);
+				$checksum = $assemblyStream->getChecksum();
+				// Only verify if it was actually computed and actually sent by client
+				if ($checksum && isset($_SERVER['HTTP_OC_CHECKSUM'])) {
+					if (strpos($_SERVER['HTTP_OC_CHECKSUM'], $checksum) === false) {
+						// We use "strpos" because client might send multiple checksums
+						throw new BadRequest('invalid checksum computed ' . $checksum . ' got ' . $_SERVER['HTTP_OC_CHECKSUM']);
+					}
+				}
+			}
+
 			// if content length is sent by client:
 			// double check if the file was fully received
 			// compare expected and actual size
@@ -216,6 +228,7 @@ public function put($data) {
 
 			$this->refreshInfo();
 
+			// FIXME: We're not doing verification yet here #11811
 			if (isset($request->server['HTTP_OC_CHECKSUM'])) {
 				$checksum = trim($request->server['HTTP_OC_CHECKSUM']);
 				$this->fileView->putFileInfo($this->path, ['checksum' => $checksum]);

apps/dav/lib/Upload/AssemblyStream.php

@@ -80,6 +80,10 @@ public function stream_open($path, $mode, $options, &$opened_path) {
 			$start += $size;
 			$this->size = $start;
 		}
+
+		// Calculate the sha1 iteratively in stream_read
+		$this->hasher = hash_init("sha1");
+
 		return true;
 	}
 
@@ -137,6 +141,8 @@ public function stream_read($count) {
 
 		// update position
 		$this->pos += $read;
+
+		hash_update($this->hasher, $data);
 		return $data;
 	}
 
@@ -273,4 +279,22 @@ private function getStream(IFile $node) {
 		return fopen('data://text/plain,' . $data,'r');
 	}
 
+	protected $hasher = null;
+	protected $sha1 = null;
+	/**
+	 * Call this only after having read the whole stream!
+	 * @return string
+	 */
+	public function getChecksum() {
+		if ($this->hasher) {
+			$this->sha1 = hash_final($this->hasher);
+			$this->hasher = null;
+		}
+		if ($this->sha1) {
+			return "SHA1:" . $this->sha1; // Same format we use at other places
+		}
+
+		return null;
+	}
+
 }

apps/dav/tests/unit/Upload/AssemblyStreamTest.php

@@ -32,6 +32,9 @@ public function testGetContents($expected, $nodes) {
 		$content = stream_get_contents($stream);
 
 		$this->assertEquals($expected, $content);
+
+		$obj = (stream_get_meta_data($stream)['wrapper_data']);
+		$this->assertEquals($obj->getChecksum(), "SHA1:".sha1($expected));
 	}
 
 	/**
@@ -46,6 +49,9 @@ public function testGetContentsFread($expected, $nodes) {
 		}
 
 		$this->assertEquals($expected, $content);
+
+		$obj = (stream_get_meta_data($stream)['wrapper_data']);
+		$this->assertEquals($obj->getChecksum(), "SHA1:".sha1($expected));
 	}
 
 	function providesNodes() {