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

net/quic/quic_crypto_client_stream.cc

Index: net/quic/quic_crypto_client_stream.cc
diff --git a/net/quic/quic_crypto_client_stream.cc b/net/quic/quic_crypto_client_stream.cc
index 3e5f84059fc0ec4567c39d1da66a18f7c3f5299c..1de80213bf0f0cce744db60cfc75c0e10caf938a 100644
--- a/net/quic/quic_crypto_client_stream.cc
+++ b/net/quic/quic_crypto_client_stream.cc
@@ -11,6 +11,7 @@
 #include "net/quic/crypto/null_encrypter.h"
 #include "net/quic/crypto/proof_verifier.h"
 #include "net/quic/crypto/proof_verifier_chromium.h"
+#include "net/quic/crypto/quic_server_info.h"
 #include "net/quic/quic_protocol.h"
 #include "net/quic/quic_session.h"
 #include "net/ssl/ssl_connection_status_flags.h"
@@ -91,7 +92,7 @@ void QuicCryptoClientStream::OnHandshakeMessage(
 }
 
 bool QuicCryptoClientStream::CryptoConnect() {
-  next_state_ = STATE_SEND_CHLO;
+  next_state_ = STATE_LOAD_QUIC_SERVER_INFO;
   DoHandshakeLoop(NULL);
   return true;
 }
@@ -159,6 +160,12 @@ void QuicCryptoClientStream::DoHandshakeLoop(
     const State state = next_state_;
     next_state_ = STATE_IDLE;
     switch (state) {
+      case STATE_LOAD_QUIC_SERVER_INFO: {
+        if (DoLoadQuicServerInfo(cached) == ERR_IO_PENDING) {
+          return;
+        }
+        break;
+      }
       case STATE_SEND_CHLO: {
         // Send the client hello in plaintext.
         session()->connection()->SetDefaultEncryptionLevel(ENCRYPTION_NONE);
@@ -166,6 +173,11 @@ void QuicCryptoClientStream::DoHandshakeLoop(
           CloseConnection(QUIC_CRYPTO_TOO_MANY_REJECTS);
           return;
         }
+        if (!cached->proof_valid() && crypto_config_->proof_verifier() &&
+            !cached->signature().empty()) {
+          next_state_ = STATE_VERIFY_PROOF;
+          break;
+        }

[wtc, 2014/02/07 00:54:11]

I think this should look like lines 274-283. In particular, we should call
cached->SetProofValid() if crypto_config_->proof_verifier() is null.

[ramant (doing other things), 2014/02/07 20:30:51]

Done.

         num_client_hellos_++;
 
         if (!cached->IsComplete(session()->connection()->clock()->WallNow())) {
@@ -318,6 +330,7 @@ void QuicCryptoClientStream::DoHandshakeLoop(
         } else {
           cached->SetProofValid();
           cached->SetProofVerifyDetails(verify_details_.release());
+          cached->SaveQuicServerInfo();

[wtc, 2014/02/07 00:54:11]

This can be refined. We only need to call cached->SaveQuicServerInfo() if the
server info comes from a REJ message, rather than from the disk cache.

[ramant (doing other things), 2014/02/07 20:30:51]

ACK (and changed the code).

We set need_to_persist_ to true only when we get REJ message.
SaveQuicServerInfo saves the data if need_to_persist_ is true.

           next_state_ = STATE_SEND_CHLO;
         }
         break;
@@ -394,4 +407,33 @@ void QuicCryptoClientStream::DoHandshakeLoop(
   }
 }
 
+void QuicCryptoClientStream::OnIOComplete(int result) {
+  DCHECK_EQ(STATE_LOAD_QUIC_SERVER_INFO, next_state_);
+  DoHandshakeLoop(NULL);
+}
+
+int QuicCryptoClientStream::DoLoadQuicServerInfo(

[wtc, 2014/02/07 00:54:11]

This function should be split into two state: STATE_LOAD_QUIC_SERVER_INFO and
STATE_LOAD_QUIC_SERVER_INFO_COMPLETE.

[ramant (doing other things), 2014/02/07 20:30:51]

Done.

+    QuicCryptoClientConfig::CachedState* cached) {
+  next_state_ = STATE_SEND_CHLO;
+  QuicServerInfo* quic_server_info = cached->quic_server_info();
+  if (!quic_server_info) {
+    return OK;
+  }
+
+  int rv = quic_server_info->WaitForDataReady(
+      base::Bind(&QuicCryptoClientStream::OnIOComplete,
+                 base::Unretained(this)));
+
+  if (rv != OK) {
+    if (rv == ERR_IO_PENDING) {
+      next_state_ = STATE_LOAD_QUIC_SERVER_INFO;
+    }
+    return rv;

[wtc, 2014/02/07 00:54:11]

We may want to return OK in this case. We should add a comment that it is fine
to proceed to STATE_SEND_CHLO when we cannot load from the disk cache. We should
log a warning message in that case.

[ramant (doing other things), 2014/02/07 20:30:51]

Done.

+  }
+
+  cached->LoadQuicServerInfo();
+
+  return rv;
+}
+
 }  // namespace net