media: Verify CDM Host files

content/common/media/cdm_host_file.cc

+// Copyright 2016 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.
+
+#include "content/common/media/cdm_host_file.h"
+
+#include <memory>
+
+#include "base/logging.h"
+#include "base/memory/ptr_util.h"
+#include "media/cdm/content_decryption_module_ext.h"
+
+namespace content {
+
+// const char kSigFileExtension[] = ".sig";
+
+std::unique_ptr<CdmHostFile> CdmHostFile::Create(
+    const base::FilePath& file_path) {
+  // Open file at |file_path|.
+  base::File file(file_path, base::File::FLAG_OPEN | base::File::FLAG_READ);
+  if (!file.IsValid()) {
+    DVLOG(1) << "Failed to open file at " << file_path.MaybeAsASCII();
+    return nullptr;
+  }
+
+  // Also open the sig file.
+
+  // HACK(xhwang): This is a HACK since we don't have a sig file now.
+  base::FilePath sig_file_path = file_path;
+
+  // base::FilePath sig_file_path = file_path.AppendASCII(kSigFileExtension);
+  base::File sig_file(sig_file_path,

[Greg K, 2017/01/09 21:45:14]

On OS X we'll need to locate the signature file in the Resources folder.

[tinskip1, 2017/01/09 23:49:30]

Specifically in the Chrome Framework.

[xhwang, 2017/01/12 20:15:02]

Good point. Will do.

[xhwang, 2017/01/18 06:03:58]

On Mac we are more interested in "Google Chrome Framework" under
"/Applications/Google Chrome.app/Contents/Versions/55.0.2883.95/Google Chrome
Framework.framework". Do I also need to put the sig file under Google Chrome
Framework.framework/Resources?

+                      base::File::FLAG_OPEN | base::File::FLAG_READ);
+  if (!sig_file.IsValid()) {
+    DVLOG(1) << "Failed to open sig file at " << sig_file_path.MaybeAsASCII();
+    return nullptr;
+  }
+
+  return std::unique_ptr<CdmHostFile>(
+      new CdmHostFile(file_path, std::move(file), std::move(sig_file)));

[jrummell, 2016/12/16 20:21:30]

I think Chromium is moving to base::MakeUnique<CdmHostFile>(file_path,
std::move(file), std::move(sig_file));

[xhwang, 2017/01/12 20:15:02]

Good point. Will do.

[xhwang, 2017/01/18 06:03:58]

Actually, now I remember why I didn't use MakeUnique: the constructor is private
so MakeUnique can't access it.

+}
+
+cdm::CdmHostFile CdmHostFile::TakePlatformFile() {
+  return cdm::CdmHostFile(file_path_.value().c_str(), file_.TakePlatformFile(),
+                          sig_file_.TakePlatformFile());
+}
+
+CdmHostFile::CdmHostFile(const base::FilePath& file_path,
+                         base::File file,
+                         base::File sig_file)
+    : file_path_(file_path),
+      file_(std::move(file)),
+      sig_file_(std::move(sig_file)) {
+  DVLOG(1) << __func__ << ": " << file_path_.value();
+  DCHECK(!file_path_.empty()) << "File path is empty.";
+  DCHECK(file_.IsValid()) << "Invalid file.";
+  DCHECK(sig_file_.IsValid()) << "Invalid signature file.";
+}
+
+}  // namespace content