[gin] Fingerprint the V8 snapshot files on Windows and verify before loading the snapshot.

content/app/content_main_runner.cc

 // Copyright (c) 2012 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/public/app/content_main_runner.h"
 
 #include <stdlib.h>
 
 #include "base/allocator/allocator_extension.h"
 #include "base/at_exit.h"
@@ skipping 703 matching lines @@
     RegisterContentSchemes(true);
 
 #if defined(OS_ANDROID)
     int icudata_fd = base::GlobalDescriptors::GetInstance()->MaybeGet(
         kAndroidICUDataDescriptor);
     if (icudata_fd != -1)
       CHECK(base::i18n::InitializeICUWithFileDescriptor(icudata_fd));
     else
       CHECK(base::i18n::InitializeICU());
 
-#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+#if defined(V8_USE_EXTERNAL_STARTUP_DATA)
     int v8_natives_fd = base::GlobalDescriptors::GetInstance()->MaybeGet(
         kV8NativesDataDescriptor);
     int v8_snapshot_fd = base::GlobalDescriptors::GetInstance()->MaybeGet(
         kV8SnapshotDataDescriptor);
     if (v8_natives_fd != -1 && v8_snapshot_fd != -1) {
       CHECK(gin::IsolateHolder::LoadV8SnapshotFD(v8_natives_fd,
                                                  v8_snapshot_fd));
     } else {
       CHECK(gin::IsolateHolder::LoadV8Snapshot());
     }
 #endif // V8_USE_EXTERNAL_STARTUP_DATA
 
 #else
     CHECK(base::i18n::InitializeICU());
-#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+#if defined(V8_USE_EXTERNAL_STARTUP_DATA)
+#if defined(OS_WIN)
+    CHECK(gin::IsolateHolder::LoadAndVerifyV8Snapshot());

[grt (UTC plus 2), 2015/01/08 17:46:35]

why should consumers need to know which platforms verify and which don't? it
seems cleaner to hide the verify-or-dont-verify smarts entirely within
gin::IsolateHolder.

[rmcilroy, 2015/01/08 18:54:14]

Sounds reasonable, done.

+#else
     CHECK(gin::IsolateHolder::LoadV8Snapshot());
-#endif // V8_USE_EXTERNAL_STARTUP_DATA
-#endif // OS_ANDROID
+#endif  // OS_WIN
+#endif  // V8_USE_EXTERNAL_STARTUP_DATA
+#endif  // OS_ANDROID
 
     InitializeStatsTable(command_line);
 
     if (delegate_)
       delegate_->PreSandboxStartup();
 
     if (!process_type.empty())
       CommonSubprocessInit(process_type);
 
 #if defined(OS_WIN)
@@ skipping 95 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(ContentMainRunnerImpl);
 };
 
 // static
 ContentMainRunner* ContentMainRunner::Create() {
   return new ContentMainRunnerImpl();
 }
 
 }  // namespace content