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

net/base/x509_certificate.h

Index: net/base/x509_certificate.h
diff --git a/net/base/x509_certificate.h b/net/base/x509_certificate.h
index 1a8b23324e947fff9805b5626ea5ee9735120866..1abbdcdb13e9663e6aecaf507127b115e587a34c 100644
--- a/net/base/x509_certificate.h
+++ b/net/base/x509_certificate.h
@@ -28,8 +28,7 @@
 #include "base/synchronization/lock.h"
 #elif defined(USE_OPENSSL)
 // Forward declaration; real one in <x509.h>
-struct x509_st;
-typedef struct x509_store_st X509_STORE;
+typedef struct x509_st X509;
 #elif defined(USE_NSS)
 // Forward declaration; real one in <cert.h>
 struct CERTCertificateStr;
@@ -55,15 +54,15 @@ typedef std::vector<scoped_refptr<X509Certificate> > CertificateList;
 class NET_EXPORT X509Certificate
     : public base::RefCountedThreadSafe<X509Certificate> {
  public:
-  // A handle to the certificate object in the underlying crypto library.
-  // We assume that OSCertHandle is a pointer type on all platforms and
-  // NULL is an invalid OSCertHandle.
+  // An OSCertHandle is a handle to a single certificate object in the

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

Nit: remove "single".  Now that OSCertListHandle is gone,
the emphasis on "a single certificate" is no longer necessary.

+  // underlying crypto library. We assume that OSCertHandle is a pointer type
+  // on all platforms and that NULL represents an invalid OSCertHandle.
 #if defined(OS_WIN)
   typedef PCCERT_CONTEXT OSCertHandle;
 #elif defined(OS_MACOSX)
   typedef SecCertificateRef OSCertHandle;
 #elif defined(USE_OPENSSL)
-  typedef struct x509_st* OSCertHandle;
+  typedef X509* OSCertHandle;
 #elif defined(USE_NSS)
   typedef struct CERTCertificateStr* OSCertHandle;
 #else
@@ -347,6 +346,10 @@ class NET_EXPORT X509Certificate
   // The content of the DER encoded certificate is written to |encoded|.
   bool GetDEREncoded(std::string* encoded);
 
+  // Returns the current OSCertHandle.

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

Nit: "the current OSCertHandle" is not clear.  How about
"the OSCertHandle of the current object" or "the
OSCertHandle of this object"?

+  // Note: On Windows, CryptoAPI may return unexpected results if this handle
+  // is used on multiple threads. See x509_util::CreateOSCertChainForCert() in
+  // net/base/x509_util_win.h for more details.
   OSCertHandle os_cert_handle() const { return cert_handle_; }
 
   // Returns true if two OSCertHandles refer to identical certificates.