Factoring a QuicCryptoServerStreamBase API out of QuicCryptoServerStream

net/quic/crypto/crypto_utils.h

 // Copyright (c) 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.
 //
 // Some helpers for quic crypto
 
 #ifndef NET_QUIC_CRYPTO_CRYPTO_UTILS_H_
 #define NET_QUIC_CRYPTO_CRYPTO_UTILS_H_
 
 #include <string>
@@ skipping 67 matching lines @@
   // Validates that |server_hello| is actually an SHLO message and that it is
   // not part of a downgrade attack.
   //
   // Returns QUIC_NO_ERROR if this is the case or returns the appropriate error
   // code and sets |error_details|.
   static QuicErrorCode ValidateServerHello(
       const CryptoHandshakeMessage& server_hello,
       const QuicVersionVector& negotiated_versions,
       std::string* error_details);
 
+  // Validates that |client_hello| is actually a CHLO and that this is not part
+  // of a downgrade attack.
+  // This includes verifiying versions and detecting downgrade attacks.
+  //
+  // Returns QUIC_NO_ERROR if this is the case or returns the appropriate error
+  // code and sets |error_details|.
+  static QuicErrorCode ValidateClientHello(
+      const CryptoHandshakeMessage& client_hello,
+      QuicVersion version,
+      const QuicVersionVector& supported_versions,
+      std::string* error_details);
+
  private:
   DISALLOW_COPY_AND_ASSIGN(CryptoUtils);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CRYPTO_CRYPTO_UTILS_H_