Persist server's crypto config data to disk cache for 0-RTT

net/quic/crypto/quic_crypto_client_config.cc

Index: net/quic/crypto/quic_crypto_client_config.cc
diff --git a/net/quic/crypto/quic_crypto_client_config.cc b/net/quic/crypto/quic_crypto_client_config.cc
index 0ce7e83d27c85ea32f3c7c6e98cc9fa55fcfc58b..a273e43fc5d1778e4fd0e65e5e109b84538e7ba8 100644
--- a/net/quic/crypto/quic_crypto_client_config.cc
+++ b/net/quic/crypto/quic_crypto_client_config.cc
@@ -38,13 +38,23 @@ QuicCryptoClientConfig::~QuicCryptoClientConfig() {
 
 QuicCryptoClientConfig::CachedState::CachedState()
     : server_config_valid_(false),
+      need_to_persist_(false),
       generation_counter_(0) {}
 
 QuicCryptoClientConfig::CachedState::CachedState(
     scoped_ptr<QuicServerInfo> quic_server_info)
     : server_config_valid_(false),
+      need_to_persist_(false),
       generation_counter_(0),
-      quic_server_info_(quic_server_info.Pass()) {}
+      quic_server_info_(quic_server_info.Pass()) {
+    if (quic_server_info_.get()) {
+      QuicServerInfo::State* state = quic_server_info_->mutable_state();
+      state->SetConfigData(&server_config_,

[wtc, 2014/02/19 02:24:11]

It is a little dangerous for quic_server_info_ to point directly at the members
of CachedState because quic_server_info_->Persist() does not complete right
away. When quic_server_info_ actually writes the data to the disk cache, the
members of CachedState may have changed.

[ramant (doing other things), 2014/02/19 02:57:53]

This change shouldn't have been uploaded. I was having issues uploading the
changes. Let me upload again. Sorry about that.

+                           &source_address_token_,
+                           &certs_,
+                           &server_config_sig_);
+    }
+}
 
 QuicCryptoClientConfig::CachedState::~CachedState() {}
 
@@ -69,6 +79,10 @@ bool QuicCryptoClientConfig::CachedState::IsComplete(QuicWallTime now) const {
   return true;
 }
 
+bool QuicCryptoClientConfig::CachedState::IsEmpty() const {
+  return server_config_.empty();
+}
+
 const CryptoHandshakeMessage*
 QuicCryptoClientConfig::CachedState::GetServerConfig() const {
   if (server_config_.empty()) {
@@ -118,6 +132,7 @@ QuicErrorCode QuicCryptoClientConfig::CachedState::SetServerConfig(
     server_config_ = server_config.as_string();
     SetProofInvalid();
     scfg_.reset(new_scfg_storage.release());
+    need_to_persist_ = true;
   }
   return QUIC_NO_ERROR;
 }
@@ -160,6 +175,7 @@ void QuicCryptoClientConfig::CachedState::ClearProof() {
 
 void QuicCryptoClientConfig::CachedState::SetProofValid() {
   server_config_valid_ = true;
+  SaveQuicServerInfo();
 }
 
 void QuicCryptoClientConfig::CachedState::SetProofInvalid() {
@@ -197,6 +213,10 @@ QuicCryptoClientConfig::CachedState::proof_verify_details() const {
   return proof_verify_details_.get();
 }
 
+QuicServerInfo* QuicCryptoClientConfig::CachedState::quic_server_info() const {
+  return quic_server_info_.get();
+}
+
 void QuicCryptoClientConfig::CachedState::set_source_address_token(
     StringPiece token) {
   source_address_token_ = token.as_string();
@@ -218,6 +238,39 @@ void QuicCryptoClientConfig::CachedState::InitializeFrom(
   server_config_valid_ = other.server_config_valid_;
 }
 
+// TODO(rtenneti): LoadQuicServerInfo and SaveQuicServerInfo have duplication of
+// data in CachedState and QuicServerInfo. We should eliminate the duplication
+// of data.

[wtc, 2014/02/19 02:24:11]

I think you should remove this TODO comment now.

+// An issue to be solved: while we are loading the data from disk cache, it is
+// possible for another request for the same hostname update the CachedState
+// because that request has sent FillInchoateClientHello and got REJ message.
+// Loading of data from disk cache shouldn't blindly overwrite what is in
+// CachedState.
+bool QuicCryptoClientConfig::CachedState::LoadQuicServerInfo(QuicWallTime now) {
+  DCHECK(server_config_.empty());
+  DCHECK(quic_server_info_.get());
+  DCHECK(quic_server_info_->IsDataReady());
+
+  // TODO (rtenneti): Implement check for expiration.
+  return true;
+}
+
+void QuicCryptoClientConfig::CachedState::SaveQuicServerInfo() {
+  if (!quic_server_info_.get() || !need_to_persist_) {
+    return;
+  }
+  DCHECK(server_config_valid_);
+
+  // If the QuicServerInfo hasn't managed to load from disk yet then we can't
+  // save anything.
+  if (!quic_server_info_->IsDataReady()) {
+    return;
+  }
+
+  quic_server_info_->Persist();
+  need_to_persist_ = false;
+}
+
 void QuicCryptoClientConfig::SetDefaults() {
   // Key exchange methods.
   kexs.resize(2);