Mac Archive Type Sniffing

chrome/browser/safe_browsing/mac_archive_type_sniffer.h

Index: chrome/browser/safe_browsing/mac_archive_type_sniffer.h
diff --git a/chrome/browser/safe_browsing/mac_archive_type_sniffer.h b/chrome/browser/safe_browsing/mac_archive_type_sniffer.h
new file mode 100644
index 0000000000000000000000000000000000000000..2480582a6d5ce7fe52fbb83ce4cfb031af0a7d59
--- /dev/null
+++ b/chrome/browser/safe_browsing/mac_archive_type_sniffer.h
@@ -0,0 +1,41 @@
+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_SAFE_BROWSING_MAC_ARCHIVE_TYPE_SNIFFER_H_
+#define CHROME_BROWSER_SAFE_BROWSING_MAC_ARCHIVE_TYPE_SNIFFER_H_
+
+#include "base/files/file.h"
+#include "base/files/file_path.h"
+#include "base/memory/ref_counted.h"
+

[Jialiu Lin, 2017/06/09 18:48:49]

nit: please remove this extra blank line

[mortonm, 2017/06/09 19:47:20]

Done.

+#include "chrome/utility/safe_browsing/mac/convert_big_endian.h"
+#include "chrome/utility/safe_browsing/mac/dmg_iterator.h"
+#include "chrome/utility/safe_browsing/mac/read_stream.h"
+#include "chrome/utility/safe_browsing/mac/udif.h"
+
+namespace safe_browsing {
+
+// This class is used to determine whether a given file is a Mac archive type,
+// regardless of file extension. It does so by determining whether the file has
+// the 'koly' signature typical of Mac archive files.
+class MacArchiveTypeSniffer
+    : public base::RefCountedThreadSafe<MacArchiveTypeSniffer> {
+ public:
+  MacArchiveTypeSniffer();
+
+  // Reads trailer from file to see if it is a DMG type. Must be called on the
+  // FILE thread.
+  static bool FileIsArchiveType(const base::FilePath& dmg_file);

[Jialiu Lin, 2017/06/09 18:48:49]

nit:  how about IsAppleDiskImage() to make it more specific?  zip is a kind of
archive too. 

[mortonm, 2017/06/09 19:47:20]

Done.

+
+ private:
+  friend class base::RefCountedThreadSafe<MacArchiveTypeSniffer>;
+
+  ~MacArchiveTypeSniffer();
+
+  DISALLOW_COPY_AND_ASSIGN(MacArchiveTypeSniffer);
+};
+
+}  // namespace safe_browsing
+
+#endif  // CHROME_BROWSER_SAFE_BROWSING_MAC_ARCHIVE_TYPE_SNIFFER_H_