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net/quic/crypto/null_encrypter.h

Index: net/quic/crypto/null_encrypter.h
diff --git a/net/quic/crypto/null_encrypter.h b/net/quic/crypto/null_encrypter.h
new file mode 100644
index 0000000000000000000000000000000000000000..3dbc1548f1037b5a4727125752cf396bf443c4b2
--- /dev/null
+++ b/net/quic/crypto/null_encrypter.h
@@ -0,0 +1,29 @@
+// 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/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 NullEncrypter : public QuicEncrypter {
+ public:
+  virtual ~NullEncrypter() {}
+
+  // QuicEncrypter implementation
+  virtual QuicData* Encrypt(base::StringPiece associated_data,
+                            base::StringPiece plaintext) OVERRIDE;
+  virtual size_t GetMaxPlaintextSize(size_t ciphertext_size) OVERRIDE;
+  virtual size_t GetCiphertextSize(size_t plaintext_size) OVERRIDE;
+};
+
+}  // namespace net
+
+#endif  // NET_QUIC_CRYPTO_NULL_ENCRYPTER_H_