Check whether or not a certificate is self-signed.

net/cert/x509_certificate_win.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 "net/cert/x509_certificate.h"
 
 #include <blapi.h>  // Implement CalculateChainFingerprint() with NSS.
 
 #include "base/logging.h"
 #include "base/memory/scoped_ptr.h"
@@ skipping 435 matching lines @@
        it != intermediate_ca_certs_.end(); ++it) {
     if (IsCertNameBlobInIssuerList(&(*it)->pCertInfo->Issuer,
                                    valid_issuers)) {
       return true;
     }
   }
 
   return false;
 }
 
+// static
+bool X509Certificate::IsSelfSigned(OSCertHandle cert_handle) {
+  return CryptVerifyCertificateSignatureEx(
+      NULL,
+      X509_ASN_ENCODING,
+      CRYPT_VERIFY_CERT_SIGN_SUBJECT_CERT,
+      cert_handle,
+      CRYPT_VERIFY_CERT_SIGN_ISSUER_CERT,
+      cert_handle,
+      0,
+      NULL);
+}
+
 }  // namespace net