[Downloads] Move client guid for AV scanning of downloaded files to chrome/

base/file_util_win.cc

Index: base/file_util_win.cc
diff --git a/base/file_util_win.cc b/base/file_util_win.cc
index 39317a3a932777a3a10f635ba9024f7a92a4746e..e4ad6401c6114423cdf48a1561140521cd0e2392 100644
--- a/base/file_util_win.cc
+++ b/base/file_util_win.cc
@@ -24,6 +24,7 @@
 #include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time/time.h"
+#include "base/win/scoped_comptr.h"
 #include "base/win/scoped_handle.h"
 #include "base/win/windows_version.h"
 
@@ -31,6 +32,12 @@ namespace base {
 
 namespace {
 
+// This GUID is associated with any 'don't ask me again' settings that the
+// user can select for different file types.
+// {2676A9A2-D919-4fee-9187-152100393AB2}
+const GUID kClientID = { 0x2676a9a2, 0xd919, 0x4fee,

[brettw, 2013/08/05 23:22:18]

I don't get what this is. Is this the GUID of the requesting app that we
generated, or some MS thing? If it's an app ID, it doesn't belong in base.

And this is copy-and-pasted from another file. This kind of thing should not be
duplicated.

[Greg Billock, 2013/08/06 15:10:24]

Yeah, I'm not sure what to do with this. It was in the initial repo checkin 5
years ago. I don't know where it came from or how. I could make it an argument.
Would that be better?

The docs at http://msdn.microsoft.com/en-us/library/ms647048.aspx say it should
be "created using uuidgen.exe and defined internally."

There's various GUIDs sitting around the codebase, but I don't know whether this
is more like a type flag or more like an app-specific thing that shouldn't be
duplicated. Any ideas on who to ask?

+  { 0x91, 0x87, 0x15, 0x21, 0x0, 0x39, 0x3a, 0xb2 } };
+
 const DWORD kFileShareAll =
     FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
 
@@ -72,6 +79,36 @@ bool ShellCopy(const FilePath& from_path,
   return (SHFileOperation(&file_operation) == 0);
 }
 
+// Sets the Zone Identifier on the file to "Internet" (3). Returns true if the
+// function succeeds, false otherwise. A failure is expected on system where
+// the Zone Identifier is not supported, like a machine with a FAT32 filesystem.
+// This function does not invoke Windows Attachment Execution Services.
+//
+// |full_path| is the path to the downloaded file.
+bool SetInternetZoneIdentifierDirectly(const base::FilePath& full_path) {
+  const DWORD kShare = FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE;
+  std::wstring path = full_path.value() + L":Zone.Identifier";
+  HANDLE file = CreateFile(path.c_str(), GENERIC_WRITE, kShare, NULL,
+                           OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
+  if (INVALID_HANDLE_VALUE == file)
+    return false;
+
+  static const char kIdentifier[] = "[ZoneTransfer]\r\nZoneId=3\r\n";
+  // Don't include trailing null in data written.
+  static const DWORD kIdentifierSize = arraysize(kIdentifier) - 1;
+  DWORD written = 0;
+  BOOL result = WriteFile(file, kIdentifier, kIdentifierSize, &written, NULL);
+  BOOL flush_result = FlushFileBuffers(file);
+  CloseHandle(file);
+
+  if (!result || !flush_result || written != kIdentifierSize) {
+    NOTREACHED();
+    return false;
+  }
+
+  return true;
+}
+
 }  // namespace
 
 FilePath MakeAbsoluteFilePath(const FilePath& input) {
@@ -147,6 +184,41 @@ bool DeleteFileAfterReboot(const FilePath& path) {
                         MOVEFILE_REPLACE_EXISTING) != FALSE;
 }
 
+HRESULT ScanAndSaveDownloadedFile(const base::FilePath& full_path,

[brettw, 2013/08/05 23:22:18]

Why is this file called "Save" downloaded file? It looks like it doesn't save
anything. Well, it calls "Save" on the attachment services, but that just saves
the flags you set.

Don't use "base::" here since you're in the base namespace. Same in header.

[Greg Billock, 2013/08/06 15:10:24]

This is copy-pasted from the code in content/. I'm happy to change it, but at
least in the initial patchset, I wanted to make it clear what was going on. My
guess is that in the MS docs, the active ingredient for IAttachmentExecute is
called "Save". Not totally accurate, though, I agree.
done

+                                  const std::string& source_url) {
+  base::win::ScopedComPtr<IAttachmentExecute> attachment_services;
+  HRESULT hr = attachment_services.CreateInstance(CLSID_AttachmentServices);
+
+  if (FAILED(hr)) {
+    // The thread must have COM initialized.
+    DCHECK_NE(CO_E_NOTINITIALIZED, hr);
+
+    // We don't have Attachment Execution Services, it must be a pre-XP.SP2
+    // Windows installation, or the thread does not have COM initialized. Try to
+    // set the zone information directly. Failure is not considered an error.
+    SetInternetZoneIdentifierDirectly(full_path);
+    return hr;
+  }
+
+  hr = attachment_services->SetClientGuid(kClientID);
+  if (FAILED(hr))
+    return hr;
+
+  hr = attachment_services->SetLocalPath(full_path.value().c_str());
+  if (FAILED(hr))
+    return hr;
+
+  if (!source_url.empty()) {
+    hr = attachment_services->SetSource(UTF8ToWide(source_url).c_str());
+    if (FAILED(hr))
+      return hr;
+  }
+
+  // A failure in the Save() call below could result in the downloaded file
+  // being deleted.
+  return attachment_services->Save();
+}
+
 bool ReplaceFile(const FilePath& from_path,
                  const FilePath& to_path,
                  PlatformFileError* error) {