Optimize CT & OCSP handling code

net/cert/ct_objects_extractor.cc

 // Copyright 2013 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/ct_objects_extractor.h"
 
 #include <string.h>
 
 #include "base/logging.h"
 #include "base/sha1.h"
@@ skipping 234 matching lines @@
     return false;
 
   result->Reset();
   result->type = ct::LogEntry::LOG_ENTRY_TYPE_X509;
   result->leaf_certificate.swap(encoded);
   return true;
 }
 
 bool ExtractSCTListFromOCSPResponse(X509Certificate::OSCertHandle issuer,
                                     const std::string& cert_serial_number,
-                                    const std::string& ocsp_response,
+                                    base::StringPiece ocsp_response,
                                     std::string* sct_list) {
   // The input is an OCSPResponse. See RFC2560, section 4.2.1. The SCT list is
   // in the extensions field of the SingleResponse which matches the input
   // certificate.
   CBS cbs;
   CBS_init(&cbs, reinterpret_cast<const uint8_t*>(ocsp_response.data()),
            ocsp_response.size());
 
   // Parse down to the ResponseBytes. The ResponseBytes is optional, but if it's
   // missing, this can't include an SCT list.
@@ skipping 76 matching lines @@
   if (!x509_exts || ptr != CBS_data(&extensions) + CBS_len(&extensions))
     return false;
 
   return GetSCTListFromX509_EXTENSIONS(x509_exts.get(), kOCSPExtensionOid,
                                        sizeof(kOCSPExtensionOid), sct_list);
 }
 
 }  // namespace ct
 
 }  // namespace net