Certificate Transparency: Add the high-level interface for verifying SCTs over multiple logs

net/cert/ct_log_verifier.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_log_verifier.h"
 
 #include "base/logging.h"
 #include "net/cert/ct_serialization.h"
 
 namespace net {
 
 // static
 scoped_ptr<CTLogVerifier> CTLogVerifier::Create(
     const base::StringPiece& public_key,
     const base::StringPiece& description) {
   scoped_ptr<CTLogVerifier> result(new CTLogVerifier());
   if (!result->Init(public_key, description))
     result.reset();
   return result.Pass();
 }
 
-bool CTLogVerifier::Verify(const ct::LogEntry& entry,
-                           const ct::SignedCertificateTimestamp& sct) {
+CTLogVerifier::VerifyResult CTLogVerifier::Verify(
+    const ct::LogEntry& entry,
+    const ct::SignedCertificateTimestamp& sct) {
   if (sct.log_id != key_id()) {
     DVLOG(1) << "SCT is not signed by this log.";
-    return false;
+    return CTLogVerifier::SCT_NOT_FROM_THIS_LOG;
   }
 
   if (sct.signature.hash_algorithm != hash_algorithm_) {
     DVLOG(1) << "Mismatched hash algorithm. Expected " << hash_algorithm_
              << ", got " << sct.signature.hash_algorithm << ".";
-    return false;
+    return CTLogVerifier::SCT_ALGORITHM_MISMATCH;
   }
 
   if (sct.signature.signature_algorithm != signature_algorithm_) {
     DVLOG(1) << "Mismatched sig algorithm. Expected " << signature_algorithm_
              << ", got " << sct.signature.signature_algorithm << ".";
-    return false;
+    return CTLogVerifier::SCT_ALGORITHM_MISMATCH;
   }
 
   std::string serialized_log_entry;
   if (!ct::EncodeLogEntry(entry, &serialized_log_entry)) {
     DVLOG(1) << "Unable to serialize entry.";
-    return false;
+    return CTLogVerifier::SCT_DATA_SERIALIZATION_FAILED;
   }
   std::string serialized_data;
   if (!ct::EncodeV1SCTSignedData(sct.timestamp, serialized_log_entry,
                                  sct.extensions, &serialized_data)) {
     DVLOG(1) << "Unable to create SCT to verify.";
-    return false;
+    return CTLogVerifier::SCT_DATA_SERIALIZATION_FAILED;
   }
 
-  return VerifySignature(serialized_data, sct.signature.signature_data);
+  if (VerifySignature(serialized_data, sct.signature.signature_data))
+    return CTLogVerifier::SCT_VERIFIED_OK;
+
+  return CTLogVerifier::SCT_VERIFICATION_FAILED;
 }
 
 }  // namespace net