text: // 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.
  
  #ifndef NET_QUIC_CRYPTO_NULL_ENCRYPTER_H_
  #define NET_QUIC_CRYPTO_NULL_ENCRYPTER_H_
  
  #include "base/compiler_specific.h"
  #include "net/base/net_export.h"
  #include "net/quic/crypto/quic_encrypter.h"
  
  namespace net {
  
  // A NullEncrypter is a QuicEncrypter used before a crypto negotiation
  // has occurred.  It does not actually encrypt the payload, but does
  // generate a MAC (fnv128) over both the payload and associated data.
  class NET_EXPORT_PRIVATE NullEncrypter : public QuicEncrypter {
   public:
    NullEncrypter();
    virtual ~NullEncrypter() {}
  
    // QuicEncrypter implementation
    virtual bool SetKey(base::StringPiece key) OVERRIDE;
    virtual bool SetNoncePrefix(base::StringPiece nonce_prefix) OVERRIDE;
    virtual bool Encrypt(base::StringPiece nonce,
                         base::StringPiece associated_data,
                         base::StringPiece plaintext,
                         unsigned char* output) OVERRIDE;
    virtual QuicData* EncryptPacket(QuicPacketSequenceNumber sequence_number,
                                    base::StringPiece associated_data,
                                    base::StringPiece plaintext) OVERRIDE;
    virtual size_t GetKeySize() const OVERRIDE;
    virtual size_t GetNoncePrefixSize() const OVERRIDE;
    virtual size_t GetMaxPlaintextSize(size_t ciphertext_size) const OVERRIDE;
    virtual size_t GetCiphertextSize(size_t plaintext_size) const OVERRIDE;
    virtual base::StringPiece GetKey() const OVERRIDE;
    virtual base::StringPiece GetNoncePrefix() const OVERRIDE;
  
   private:
    size_t GetHashLength() const;
  };
  
  }  // namespace net
  
  #endif  // NET_QUIC_CRYPTO_NULL_ENCRYPTER_H_
  