Ensure X509Certificate::OSCertHandles are safe to be used on both UI and IO threads on Win

chrome/browser/ui/views/certificate_viewer_win.cc

Index: chrome/browser/ui/views/certificate_viewer_win.cc
diff --git a/chrome/browser/ui/views/certificate_viewer_win.cc b/chrome/browser/ui/views/certificate_viewer_win.cc
index ba54267100e94e820eaaca1da10b65bedfbacd9d..7d8ababfdd46ddbac8e28c13704f7a06ab7f0ee0 100644
--- a/chrome/browser/ui/views/certificate_viewer_win.cc
+++ b/chrome/browser/ui/views/certificate_viewer_win.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
@@ -8,10 +8,15 @@
 #include <cryptuiapi.h>
 #pragma comment(lib, "cryptui.lib")
 
+#include "base/logging.h"
 #include "net/base/x509_certificate.h"
+#include "net/base/x509_util_win.h"
 
 void ShowCertificateViewer(gfx::NativeWindow parent,
                            net::X509Certificate* cert) {
+  PCCERT_CONTEXT cert_list = net::x509_util::CreateOSCertChainForCert(cert);
+  CHECK(cert_list);
+
   CRYPTUI_VIEWCERTIFICATE_STRUCT view_info = { 0 };
   view_info.dwSize = sizeof(view_info);
   // We set our parent to the tab window. This makes the cert dialog created
@@ -19,9 +24,9 @@ void ShowCertificateViewer(gfx::NativeWindow parent,
   view_info.hwndParent = parent;
   view_info.dwFlags = CRYPTUI_DISABLE_EDITPROPERTIES |
                       CRYPTUI_DISABLE_ADDTOSTORE;
-  view_info.pCertContext = cert->os_cert_handle();
+  view_info.pCertContext = cert_list;
   // Search the cert store that 'cert' is in when building the cert chain.

[wtc, 2011/10/16 14:55:49]

Nit: this comment sounds weird since the code now uses
'cert_list', not 'cert'.  Also, the cert store is now
specifically constructed for this operation.

We should update this comment (e.g., "Search the cert
store that contains the cert and its intermediate CAs
when building the cert chain").  But I think we can also
simply remove the comment.

-  HCERTSTORE cert_store = view_info.pCertContext->hCertStore;
+  HCERTSTORE cert_store = cert_list->hCertStore;
   view_info.cStores = 1;
   view_info.rghStores = &cert_store;
   BOOL properties_changed;
@@ -29,4 +34,6 @@ void ShowCertificateViewer(gfx::NativeWindow parent,
   // This next call blocks but keeps processing windows messages, making it
   // modal to the browser window.
   BOOL rv = ::CryptUIDlgViewCertificate(&view_info, &properties_changed);
+
+  CertFreeCertificateContext(cert_list);
 }