Land recent QUIC changes.

net/quic/crypto/quic_encrypter.h

 // 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_QUIC_ENCRYPTER_H_
 #define NET_QUIC_CRYPTO_QUIC_ENCRYPTER_H_
 
 #include "net/base/net_export.h"
 #include "net/quic/crypto/crypto_protocol.h"
 #include "net/quic/quic_protocol.h"
 
 namespace net {
 
 class NET_EXPORT_PRIVATE QuicEncrypter {
  public:
   virtual ~QuicEncrypter() {}
 
   static QuicEncrypter* Create(CryptoTag algorithm);
 
+  // Sets the encryption key. Returns true on success, false on failure.
+  //
+  // NOTE: The key is the client_write_key or server_write_key derived from
+  // the master secret.
+  virtual bool SetKey(base::StringPiece key) = 0;
+
+  // Sets the fixed initial bytes of the nonce. Returns true on success,
+  // false on failure.
+  //
+  // NOTE: The nonce prefix is the client_write_iv or server_write_iv
+  // derived from the master secret. A 64-bit packet sequence number will
+  // be appended to form the nonce.
+  //
+  //                          <------------ 64 bits ----------->
+  //   +---------------------+----------------------------------+
+  //   |    Fixed prefix     |      Packet sequence number      |
+  //   +---------------------+----------------------------------+
+  //                          Nonce format
+  //
+  // The security of the nonce format requires that QUIC never reuse a
+  // packet sequence number, even when retransmitting a lost packet.
+  virtual bool SetNoncePrefix(base::StringPiece nonce_prefix) = 0;
+
   // Returns a newly created QuicData object containing the encrypted
   // |plaintext| as well as a MAC over both |plaintext| and |associated_data|,
-  // or NULL if there is an error.
-  virtual QuicData* Encrypt(base::StringPiece associated_data,
+  // or NULL if there is an error. |sequence_number| is appended to the
+  // |nonce_prefix| value provided in SetNoncePrefix() to form the nonce.
+  virtual QuicData* Encrypt(QuicPacketSequenceNumber sequence_number,
+                            base::StringPiece associated_data,
                             base::StringPiece plaintext) = 0;
 
+  // GetKeySize() and GetNoncePrefixSize() tell the HKDF class how many bytes
+  // of key material needs to be derived from the master secret.
+  // NOTE: the sizes returned by GetKeySize() and GetNoncePrefixSize() are
+  // also correct for the QuicDecrypter of the same algorithm. So only
+  // QuicEncrypter has these two methods.
+
+  // Returns the size in bytes of a key for the algorithm.
+  virtual size_t GetKeySize() const = 0;
+  // Returns the size in bytes of the fixed initial part of the nonce.
+  virtual size_t GetNoncePrefixSize() const = 0;
+
   // Returns the maximum length of plaintext that can be encrypted
   // to ciphertext no larger than |ciphertext_size|.
-  virtual size_t GetMaxPlaintextSize(size_t ciphertext_size) = 0;
+  virtual size_t GetMaxPlaintextSize(size_t ciphertext_size) const = 0;
 
   // Returns the length of the ciphertext that would be generated by encrypting
   // to plaintext of size |plaintext_size|.
-  virtual size_t GetCiphertextSize(size_t plaintext_size) = 0;
-
+  virtual size_t GetCiphertextSize(size_t plaintext_size) const = 0;
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CRYPTO_QUIC_ENCRYPTER_H_