Certificate Transparency: Parse Signed Tree Heads and validate them

net/cert/signed_certificate_timestamp.h

 // 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.
 
 #ifndef NET_CERT_SIGNED_CERTIFICATE_TIMESTAMP_H_
 #define NET_CERT_SIGNED_CERTIFICATE_TIMESTAMP_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 48 matching lines @@
   enum SignatureAlgorithm {
     SIG_ALGO_ANONYMOUS = 0,
     SIG_ALGO_RSA = 1,
     SIG_ALGO_DSA = 2,
     SIG_ALGO_ECDSA = 3
   };
 
   DigitallySigned();
   ~DigitallySigned();
 
+  // Returns true if |other_hash_algorithm| and |other_signature_algorithm|
+  // match this DigitallySigned hash and signature algorithms.
+  bool SignatureParametersMatch(
+      HashAlgorithm other_hash_algorithm,
+      SignatureAlgorithm other_signature_algorithm) const;
+
   HashAlgorithm hash_algorithm;
   SignatureAlgorithm signature_algorithm;
   // 'signature' field.
   std::string signature_data;
 };
 
 // SignedCertificateTimestamp struct in RFC 6962, Section 3.2.
 struct NET_EXPORT SignedCertificateTimestamp
     : public base::RefCountedThreadSafe<SignedCertificateTimestamp> {
   // Predicate functor used in maps when SignedCertificateTimestamp is used as
@@ skipping 44 matching lines @@
   ~SignedCertificateTimestamp();
 
   DISALLOW_COPY_AND_ASSIGN(SignedCertificateTimestamp);
 };
 
 }  // namespace ct
 
 }  // namespace net
 
 #endif  // NET_CERT_SIGNED_CERTIFICATE_TIMESTAMP_H_