QUIC: if client provides an STK which includes CachedNetworkParams, then

net/quic/quic_crypto_server_stream.cc

 // 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.
 
 #include "net/quic/quic_crypto_server_stream.h"
 
 #include "base/base64.h"
 #include "crypto/secure_hash.h"
 #include "net/quic/crypto/crypto_protocol.h"
 #include "net/quic/crypto/crypto_utils.h"
 #include "net/quic/crypto/quic_crypto_server_config.h"
 #include "net/quic/crypto/source_address_token.h"
 #include "net/quic/quic_config.h"
+#include "net/quic/quic_flags.h"
 #include "net/quic/quic_protocol.h"
 #include "net/quic/quic_session.h"
 
 namespace net {
 
 void ServerHelloNotifier::OnAckNotification(
     int num_original_packets,
     int num_original_bytes,
     int num_retransmitted_packets,
     int num_retransmitted_bytes,
@@ skipping 121 matching lines @@
   session()->connection()->SetAlternativeDecrypter(
       crypto_negotiated_params_.forward_secure_crypters.decrypter.release(),
       ENCRYPTION_FORWARD_SECURE, false /* don't latch */);
 
   encryption_established_ = true;
   handshake_confirmed_ = true;
   session()->OnCryptoHandshakeEvent(QuicSession::HANDSHAKE_CONFIRMED);
 
   // Now that the handshake is complete, send an updated server config and
   // source-address token to the client.
-  SendServerConfigUpdate(nullptr);
+  SendServerConfigUpdate(previous_cached_network_params_.get(), true);
 }
 
 void QuicCryptoServerStream::SendServerConfigUpdate(
-    const CachedNetworkParameters* cached_network_params) {
+    const CachedNetworkParameters* cached_network_params,
+    bool on_handshake_complete) {
   if (session()->connection()->version() <= QUIC_VERSION_21 ||
       !handshake_confirmed_) {
     return;
   }
 
   CryptoHandshakeMessage server_config_update_message;
   if (!crypto_config_.BuildServerConfigUpdateMessage(
           session()->connection()->peer_address(),
           session()->connection()->clock(),
           session()->connection()->random_generator(),
           crypto_negotiated_params_,
           cached_network_params,
           &server_config_update_message)) {
     DVLOG(1) << "Server: Failed to build server config update (SCUP)!";
     return;
   }
 
-  DVLOG(1) << "Server: Sending server config update: "
+  DVLOG(1) << "Server: Sending server config update"
+           << (on_handshake_complete ? " immediately after handshake: " : ": ")
            << server_config_update_message.DebugString();
   const QuicData& data = server_config_update_message.GetSerialized();
   WriteOrBufferData(string(data.data(), data.length()), false, nullptr);
 
   ++num_server_config_update_messages_sent_;
 }
 
 void QuicCryptoServerStream::OnServerHelloAcked() {
   session()->connection()->OnHandshakeComplete();
 }
@@ skipping 26 matching lines @@
     }
   }
   return true;
 }
 
 QuicErrorCode QuicCryptoServerStream::ProcessClientHello(
     const CryptoHandshakeMessage& message,
     const ValidateClientHelloResultCallback::Result& result,
     CryptoHandshakeMessage* reply,
     string* error_details) {
+  // Store the bandwidth estimate from the client.
+  if (FLAGS_quic_store_cached_network_params_from_chlo &&
+      result.cached_network_params.bandwidth_estimate_bytes_per_second() > 0) {
+    previous_cached_network_params_.reset(
+        new CachedNetworkParameters(result.cached_network_params));
+  }
+
   return crypto_config_.ProcessClientHello(
       result,
       session()->connection()->connection_id(),
       session()->connection()->peer_address(),
       session()->connection()->version(),
       session()->connection()->supported_versions(),
       session()->connection()->clock(),
       session()->connection()->random_generator(),
       &crypto_negotiated_params_, reply, error_details);
 }
 
 void QuicCryptoServerStream::OverrideQuicConfigDefaults(QuicConfig* config) {
 }
 
 QuicCryptoServerStream::ValidateCallback::ValidateCallback(
     QuicCryptoServerStream* parent) : parent_(parent) {
 }
 
 void QuicCryptoServerStream::ValidateCallback::Cancel() { parent_ = nullptr; }
 
 void QuicCryptoServerStream::ValidateCallback::RunImpl(
     const CryptoHandshakeMessage& client_hello,
     const Result& result) {
   if (parent_ != nullptr) {
     parent_->FinishProcessingHandshakeMessage(client_hello, result);
   }
 }
 
 }  // namespace net