Include the socket receive buffer in the connection handshake.

net/quic/crypto/crypto_protocol.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_CRYPTO_PROTOCOL_H_
 #define NET_QUIC_CRYPTO_CRYPTO_PROTOCOL_H_
 
 #include <string>
 
 #include "net/base/net_export.h"
@@ skipping 26 matching lines @@
 
 // Key exchange methods
 const QuicTag kP256 = TAG('P', '2', '5', '6');   // ECDH, Curve P-256
 const QuicTag kC255 = TAG('C', '2', '5', '5');   // ECDH, Curve25519
 
 // AEAD algorithms
 const QuicTag kNULL = TAG('N', 'U', 'L', 'N');   // null algorithm
 const QuicTag kAESG = TAG('A', 'E', 'S', 'G');   // AES128 + GCM-12
 const QuicTag kCC12 = TAG('C', 'C', '1', '2');   // ChaCha20 + Poly1305
 
+// Socket receive buffer
+const QuicTag kSRBF = TAG('S', 'R', 'B', 'F');   // Socket receive buffer
+
 // Congestion control feedback types
 const QuicTag kQBIC = TAG('Q', 'B', 'I', 'C');   // TCP cubic
 const QuicTag kPACE = TAG('P', 'A', 'C', 'E');   // Paced TCP cubic
 const QuicTag kTSTP = TAG('T', 'S', 'T', 'P');   // Timestamp
 
 // Congestion control options
 const QuicTag kTBBR = TAG('T', 'B', 'B', 'R');   // Reduced Buffer Bloat TCP
 const QuicTag kRENO = TAG('R', 'E', 'N', 'O');   // Reno Congestion Control
 const QuicTag kIW10 = TAG('I', 'W', '1', '0');   // Force ICWND to 10
 
@@ skipping 107 matching lines @@
 // amplification factor of any mirror DoS attack.
 //
 // A client may pad an inchoate client hello to a size larger than
 // kClientHelloMinimumSize to make it more likely to receive a complete
 // rejection message.
 const size_t kClientHelloMinimumSize = 1024;
 
 }  // namespace net
 
 #endif  // NET_QUIC_CRYPTO_CRYPTO_PROTOCOL_H_