Add debugging information to the SSL blocking page

net/cert/x509_certificate_mac.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 <CommonCrypto/CommonDigest.h>
 #include <CoreServices/CoreServices.h>
 #include <Security/Security.h>
 
@@ skipping 256 matching lines @@
           reinterpret_cast<const char*>(name_data.Data),
           name_data.Length));
     }
   }
 }
 
 // static
 bool X509Certificate::GetDEREncoded(X509Certificate::OSCertHandle cert_handle,
                                     std::string* encoded) {
   CSSM_DATA der_data;
-  if (SecCertificateGetData(cert_handle, &der_data) != noErr)
+  if (!cert_handle || SecCertificateGetData(cert_handle, &der_data) != noErr)
     return false;
   encoded->assign(reinterpret_cast<char*>(der_data.Data),
                   der_data.Length);
   return true;
 }
 
 // static
 bool X509Certificate::IsSameOSCert(X509Certificate::OSCertHandle a,
                                    X509Certificate::OSCertHandle b) {
   DCHECK(a && b);
@@ skipping 219 matching lines @@
       *type = kPublicKeyTypeDH;
       break;
     default:
       *type = kPublicKeyTypeUnknown;
       *size_bits = 0;
       break;
   }
 }
 
 }  // namespace net