Implements new, more robust design for communicating between SSLConnectJobs.

net/socket/ssl_client_socket_pool.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/socket/ssl_client_socket_pool.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
@@ skipping 76 matching lines @@
   DCHECK_EQ(GetConnectionType(), SOCKS_PROXY);
   return socks_proxy_params_;
 }
 
 const scoped_refptr<HttpProxySocketParams>&
 SSLSocketParams::GetHttpProxyConnectionParams() const {
   DCHECK_EQ(GetConnectionType(), HTTP_PROXY);
   return http_proxy_params_;
 }
 
+bool SSLConnectJobMessenger::CanProceed(SSLClientSocket* ssl_socket) {
+  // If the session is in the session cache, or there are no connecting
+  // sockets allow the connection to proceed.
+  if (ssl_socket->InSessionCache() || connecting_sockets_.empty()) {
+    return true;
+  }
+  return false;

[wtc, 2014/07/11 00:48:55]

You can just say
  return ssl_socket->InSessionCache() || connecting_sockets_.empty();

[mshelley, 2014/07/11 23:26:27]

Done.

+}
+
+void SSLConnectJobMessenger::MonitorConnectionResult(
+    SSLClientSocket* ssl_socket) {
+  connecting_sockets_.push_back(ssl_socket);
+  ssl_socket->SetIsLeader();
+  ssl_socket->SetSocketFailureCallback(
+      base::Bind(&SSLConnectJobMessenger::OnJobFailed, base::Unretained(this)));
+  ssl_socket->WatchSessionForCompletion(base::Bind(
+      &SSLConnectJobMessenger::OnJobSucceeded, base::Unretained(this)));

[wtc, 2014/07/11 00:48:54]

IMPORTANT: we need to convince ourselves that we don't need to pass weak
pointers of the Messenger. I think this is correct, but this requires careful
checking.

In particular, this means the Messenger destructor needs to assert that
connecting_sockets_ is empty.

+}
+
+void SSLConnectJobMessenger::AddPendingSocket(SSLClientSocket* socket,
+                                              const base::Closure& callback) {
+  pending_sockets_and_callbacks_.push_back(SocketAndCallback(socket, callback));
+}
+
+void SSLConnectJobMessenger::OnJobSucceeded() {
+  SSLPendingSocketsAndCallbacks temp_list = pending_sockets_and_callbacks_;
+  pending_sockets_and_callbacks_.clear();
+  connecting_sockets_.clear();
+  RunAllJobs(temp_list);
+}
+
+void SSLConnectJobMessenger::OnJobFailed() {
+  if (pending_sockets_and_callbacks_.empty())
+    return;
+  base::Closure callback = pending_sockets_and_callbacks_[0].callback;
+  connecting_sockets_.erase(connecting_sockets_.begin());
+  SSLClientSocket* ssl_socket = pending_sockets_and_callbacks_[0].socket;
+  pending_sockets_and_callbacks_.erase(pending_sockets_and_callbacks_.begin());
+  MonitorConnectionResult(ssl_socket);
+  callback.Run();
+}
+
+void SSLConnectJobMessenger::RunAllJobs(
+    std::vector<SocketAndCallback>& pending_sockets_and_callbacks) {
+  for (std::vector<SocketAndCallback>::const_iterator it =
+           pending_sockets_and_callbacks.begin();
+       it != pending_sockets_and_callbacks.end();
+       ++it)
+    it->callback.Run();
+}
+
 // Timeout for the SSL handshake portion of the connect.
 static const int kSSLHandshakeTimeoutInSeconds = 30;
 
 SSLConnectJob::SSLConnectJob(const std::string& group_name,
                              RequestPriority priority,
                              const scoped_refptr<SSLSocketParams>& params,
                              const base::TimeDelta& timeout_duration,
                              TransportClientSocketPool* transport_pool,
                              SOCKSClientSocketPool* socks_pool,
                              HttpProxyClientSocketPool* http_proxy_pool,
                              ClientSocketFactory* client_socket_factory,
                              HostResolver* host_resolver,
                              const SSLClientSocketContext& context,
+                             SSLConnectJobMessenger* messenger,
                              Delegate* delegate,
                              NetLog* net_log)
     : ConnectJob(group_name,
                  timeout_duration,
                  priority,
                  delegate,
                  BoundNetLog::Make(net_log, NetLog::SOURCE_CONNECT_JOB)),
       params_(params),
       transport_pool_(transport_pool),
       socks_pool_(socks_pool),
       http_proxy_pool_(http_proxy_pool),
       client_socket_factory_(client_socket_factory),
       host_resolver_(host_resolver),
       context_(context.cert_verifier,
                context.server_bound_cert_service,
                context.transport_security_state,
                context.cert_transparency_verifier,
                (params->privacy_mode() == PRIVACY_MODE_ENABLED
                     ? "pm/" + context.ssl_session_cache_shard
                     : context.ssl_session_cache_shard)),
-      callback_(base::Bind(&SSLConnectJob::OnIOComplete,
-                           base::Unretained(this))) {}
+      io_callback_(
+          base::Bind(&SSLConnectJob::OnIOComplete, base::Unretained(this))),
+      messenger_(messenger),
+      weak_factory_(this) {
+}
 
 SSLConnectJob::~SSLConnectJob() {}

[wtc, 2014/07/11 00:48:54]

IMPORTANT: we should remove the SSLClientSocket of the SSLConnectJob from the
Messenger.

[mshelley, 2014/07/11 23:26:27]

Done.

 
 LoadState SSLConnectJob::GetLoadState() const {
   switch (next_state_) {
     case STATE_TUNNEL_CONNECT_COMPLETE:
       if (transport_socket_handle_->socket())
         return LOAD_STATE_ESTABLISHING_PROXY_TUNNEL;
       // else, fall through.
     case STATE_TRANSPORT_CONNECT:
     case STATE_TRANSPORT_CONNECT_COMPLETE:
     case STATE_SOCKS_CONNECT:
     case STATE_SOCKS_CONNECT_COMPLETE:
     case STATE_TUNNEL_CONNECT:
       return transport_socket_handle_->GetLoadState();
+    case STATE_CREATE_SSL_SOCKET:
+    case STATE_CHECK_FOR_RESUME:
     case STATE_SSL_CONNECT:
     case STATE_SSL_CONNECT_COMPLETE:
       return LOAD_STATE_SSL_HANDSHAKE;
     default:
       NOTREACHED();
       return LOAD_STATE_IDLE;
   }
 }
 
 void SSLConnectJob::GetAdditionalErrorState(ClientSocketHandle* handle) {
@@ skipping 36 matching lines @@
       case STATE_SOCKS_CONNECT_COMPLETE:
         rv = DoSOCKSConnectComplete(rv);
         break;
       case STATE_TUNNEL_CONNECT:
         DCHECK_EQ(OK, rv);
         rv = DoTunnelConnect();
         break;
       case STATE_TUNNEL_CONNECT_COMPLETE:
         rv = DoTunnelConnectComplete(rv);
         break;
+      case STATE_CREATE_SSL_SOCKET:
+        rv = DoCreateSSLSocket();
+        break;
+      case STATE_CHECK_FOR_RESUME:
+        rv = DoCheckForResume();
+        break;
       case STATE_SSL_CONNECT:
         DCHECK_EQ(OK, rv);
         rv = DoSSLConnect();
         break;
       case STATE_SSL_CONNECT_COMPLETE:
         rv = DoSSLConnectComplete(rv);
         break;
       default:
         NOTREACHED() << "bad state";
         rv = ERR_FAILED;
         break;
     }
   } while (rv != ERR_IO_PENDING && next_state_ != STATE_NONE);
 
   return rv;
 }
 
 int SSLConnectJob::DoTransportConnect() {
   DCHECK(transport_pool_);
 
   next_state_ = STATE_TRANSPORT_CONNECT_COMPLETE;
   transport_socket_handle_.reset(new ClientSocketHandle());
   scoped_refptr<TransportSocketParams> direct_params =
       params_->GetDirectConnectionParams();
   return transport_socket_handle_->Init(group_name(),
                                         direct_params,
                                         priority(),
-                                        callback_,
+                                        io_callback_,
                                         transport_pool_,
                                         net_log());
 }
 
 int SSLConnectJob::DoTransportConnectComplete(int result) {
-  if (result == OK)
-    next_state_ = STATE_SSL_CONNECT;
+  if (result != OK)
+    return result;
+
+  next_state_ = STATE_CREATE_SSL_SOCKET;
 
   return result;
 }
 
 int SSLConnectJob::DoSOCKSConnect() {
   DCHECK(socks_pool_);
   next_state_ = STATE_SOCKS_CONNECT_COMPLETE;
   transport_socket_handle_.reset(new ClientSocketHandle());
   scoped_refptr<SOCKSSocketParams> socks_proxy_params =
       params_->GetSocksProxyConnectionParams();
   return transport_socket_handle_->Init(group_name(),
                                         socks_proxy_params,
                                         priority(),
-                                        callback_,
+                                        io_callback_,
                                         socks_pool_,
                                         net_log());
 }
 
 int SSLConnectJob::DoSOCKSConnectComplete(int result) {
-  if (result == OK)
-    next_state_ = STATE_SSL_CONNECT;
+  if (result != OK)
+    return result;
+
+  next_state_ = STATE_CREATE_SSL_SOCKET;
 
   return result;
 }
 
 int SSLConnectJob::DoTunnelConnect() {
   DCHECK(http_proxy_pool_);
   next_state_ = STATE_TUNNEL_CONNECT_COMPLETE;
 
   transport_socket_handle_.reset(new ClientSocketHandle());
   scoped_refptr<HttpProxySocketParams> http_proxy_params =
       params_->GetHttpProxyConnectionParams();
   return transport_socket_handle_->Init(group_name(),
                                         http_proxy_params,
                                         priority(),
-                                        callback_,
+                                        io_callback_,
                                         http_proxy_pool_,
                                         net_log());
 }
 
 int SSLConnectJob::DoTunnelConnectComplete(int result) {
   // Extract the information needed to prompt for appropriate proxy
   // authentication so that when ClientSocketPoolBaseHelper calls
   // |GetAdditionalErrorState|, we can easily set the state.
   if (result == ERR_SSL_CLIENT_AUTH_CERT_NEEDED) {
     error_response_info_ = transport_socket_handle_->ssl_error_response_info();
   } else if (result == ERR_PROXY_AUTH_REQUESTED ||
              result == ERR_HTTPS_PROXY_TUNNEL_RESPONSE) {
     StreamSocket* socket = transport_socket_handle_->socket();
     HttpProxyClientSocket* tunnel_socket =
         static_cast<HttpProxyClientSocket*>(socket);
     error_response_info_ = *tunnel_socket->GetConnectResponseInfo();
   }
   if (result < 0)
     return result;
 
-  next_state_ = STATE_SSL_CONNECT;
+  next_state_ = STATE_CREATE_SSL_SOCKET;
   return result;
 }
 
-int SSLConnectJob::DoSSLConnect() {
-  next_state_ = STATE_SSL_CONNECT_COMPLETE;
+int SSLConnectJob::DoCreateSSLSocket() {
+  if (SSLClientSocketPool::GetEnableConnectJobWaiting())

[wtc, 2014/07/11 00:48:55]

You can just test |messenger_|.

[mshelley, 2014/07/11 23:26:27]

Done.

+    next_state_ = STATE_CHECK_FOR_RESUME;
+  else
+    next_state_ = STATE_SSL_CONNECT;
   // Reset the timeout to just the time allowed for the SSL handshake.
   ResetTimer(base::TimeDelta::FromSeconds(kSSLHandshakeTimeoutInSeconds));
 
   // If the handle has a fresh socket, get its connect start and DNS times.
   // This should always be the case.
   const LoadTimingInfo::ConnectTiming& socket_connect_timing =
       transport_socket_handle_->connect_timing();
   if (!transport_socket_handle_->is_reused() &&
       !socket_connect_timing.connect_start.is_null()) {
     // Overwriting |connect_start| serves two purposes - it adjusts timing so
     // |connect_start| doesn't include dns times, and it adjusts the time so
     // as not to include time spent waiting for an idle socket.
     connect_timing_.connect_start = socket_connect_timing.connect_start;
     connect_timing_.dns_start = socket_connect_timing.dns_start;
     connect_timing_.dns_end = socket_connect_timing.dns_end;
   }
 
-  connect_timing_.ssl_start = base::TimeTicks::Now();
-
   ssl_socket_ = client_socket_factory_->CreateSSLClientSocket(
       transport_socket_handle_.Pass(),
       params_->host_and_port(),
       params_->ssl_config(),
       context_);
-  return ssl_socket_->Connect(callback_);
+  return OK;
+}
+
+int SSLConnectJob::DoCheckForResume() {
+  next_state_ = STATE_SSL_CONNECT;
+  if (messenger_->CanProceed(ssl_socket_.get())) {
+    if (ssl_socket_->InSessionCache())

[wtc, 2014/07/11 00:48:55]

Doing it this way means we are calling ssl_socket_->InSessionCache() twice. This
should be avoided.

You can go back to your old function prototype for CanProceed, or change
CanProceed to return a three-value enum type.

Another solution is to have messenger provide two methods:
  InSessionCache()
  HasConnectingSockets()

[mshelley, 2014/07/11 23:26:27]

Acknowledged.

+      return OK;
+    messenger_->MonitorConnectionResult(ssl_socket_.get());
+    return OK;
+  }
+  messenger_->AddPendingSocket(
+      ssl_socket_.get(),
+      base::Bind(&net::SSLConnectJob::ResumeSSLConnection,
+                 weak_factory_.GetWeakPtr()));

[wtc, 2014/07/11 00:48:55]

IMPORTANT: this weak pointer only protects the job resumption callback, but note
that we also pass the ssl_socket_ pointer to the Messenger, and the Messenger
will use it at the end of OnJobFailed():
	
  MonitorConnectionResult(ssl_socket);  <== PROBLEM
  callback.Run();  <== Protected by the weak pointer

[mshelley, 2014/07/11 23:26:27]

Done.

+  return ERR_IO_PENDING;
+}
+
+int SSLConnectJob::DoSSLConnect() {
+  next_state_ = STATE_SSL_CONNECT_COMPLETE;
+
+  connect_timing_.ssl_start = base::TimeTicks::Now();
+
+  return ssl_socket_->Connect(io_callback_);
 }
 
 int SSLConnectJob::DoSSLConnectComplete(int result) {
   connect_timing_.ssl_end = base::TimeTicks::Now();
 
+  if (result != OK && SSLClientSocketPool::GetEnableConnectJobWaiting())

[wtc, 2014/07/11 00:48:54]

1. BUG? : messenger_->OnJobFailed() will be invoked by SSLClientSocket, so I
think we should delete lines 421-422.

2. (Only if this code should stay) We should be able to replace the
SSLClientSocketPool::GetEnableConnectJobWaiting() test with |messenger_|:

  if (result != OK && messenger_)
    messenger_->OnJobFailed();

[mshelley, 2014/07/11 23:26:27]

Done.

+    messenger_->OnJobFailed();
+
   SSLClientSocket::NextProtoStatus status =
       SSLClientSocket::kNextProtoUnsupported;
   std::string proto;
   std::string server_protos;
   // GetNextProto will fail and and trigger a NOTREACHED if we pass in a socket
   // that hasn't had SSL_ImportFD called on it. If we get a certificate error
   // here, then we know that we called SSL_ImportFD.
   if (result == OK || IsCertificateError(result))
     status = ssl_socket_->GetNextProto(&proto, &server_protos);
 
@@ skipping 64 matching lines @@
                                  100);
     } else if (ssl_info.handshake_type == SSLInfo::HANDSHAKE_FULL) {
       UMA_HISTOGRAM_CUSTOM_TIMES("Net.SSL_Connection_Latency_Full_Handshake",
                                  connect_duration,
                                  base::TimeDelta::FromMilliseconds(1),
                                  base::TimeDelta::FromMinutes(1),
                                  100);
     }
 
     const std::string& host = params_->host_and_port().host();
-    bool is_google = host == "google.com" ||
-                     (host.size() > 11 &&
-                      host.rfind(".google.com") == host.size() - 11);
+    bool is_google =
+        host == "google.com" ||
+        (host.size() > 11 && host.rfind(".google.com") == host.size() - 11);
     if (is_google) {
       UMA_HISTOGRAM_CUSTOM_TIMES("Net.SSL_Connection_Latency_Google2",
                                  connect_duration,
                                  base::TimeDelta::FromMilliseconds(1),
                                  base::TimeDelta::FromMinutes(1),
                                  100);
       if (ssl_info.handshake_type == SSLInfo::HANDSHAKE_RESUME) {
         UMA_HISTOGRAM_CUSTOM_TIMES("Net.SSL_Connection_Latency_Google_"
                                        "Resume_Handshake",
                                    connect_duration,
@@ skipping 15 matching lines @@
     SetSocket(ssl_socket_.PassAs<StreamSocket>());
   } else if (result == ERR_SSL_CLIENT_AUTH_CERT_NEEDED) {
     error_response_info_.cert_request_info = new SSLCertRequestInfo;
     ssl_socket_->GetSSLCertRequestInfo(
         error_response_info_.cert_request_info.get());
   }
 
   return result;
 }
 
+void SSLConnectJob::ResumeSSLConnection() {
+  DCHECK_EQ(next_state_, STATE_SSL_CONNECT);
+  OnIOComplete(OK);
+}
+
 SSLConnectJob::State SSLConnectJob::GetInitialState(
     SSLSocketParams::ConnectionType connection_type) {
   switch (connection_type) {
     case SSLSocketParams::DIRECT:
       return STATE_TRANSPORT_CONNECT;
     case SSLSocketParams::HTTP_PROXY:
       return STATE_TUNNEL_CONNECT;
     case SSLSocketParams::SOCKS_PROXY:
       return STATE_SOCKS_CONNECT;
   }
@@ skipping 13 matching lines @@
     ClientSocketFactory* client_socket_factory,
     HostResolver* host_resolver,
     const SSLClientSocketContext& context,
     NetLog* net_log)
     : transport_pool_(transport_pool),
       socks_pool_(socks_pool),
       http_proxy_pool_(http_proxy_pool),
       client_socket_factory_(client_socket_factory),
       host_resolver_(host_resolver),
       context_(context),
-      net_log_(net_log) {
+      net_log_(net_log),
+      messenger_map_(new MessengerMap) {
   base::TimeDelta max_transport_timeout = base::TimeDelta();
   base::TimeDelta pool_timeout;
   if (transport_pool_)
     max_transport_timeout = transport_pool_->ConnectionTimeout();
   if (socks_pool_) {
     pool_timeout = socks_pool_->ConnectionTimeout();
     if (pool_timeout > max_transport_timeout)
       max_transport_timeout = pool_timeout;
   }
   if (http_proxy_pool_) {
@@ skipping 17 matching lines @@
     const std::string& ssl_session_cache_shard,
     ClientSocketFactory* client_socket_factory,
     TransportClientSocketPool* transport_pool,
     SOCKSClientSocketPool* socks_pool,
     HttpProxyClientSocketPool* http_proxy_pool,
     SSLConfigService* ssl_config_service,
     NetLog* net_log)
     : transport_pool_(transport_pool),
       socks_pool_(socks_pool),
       http_proxy_pool_(http_proxy_pool),
-      base_(this, max_sockets, max_sockets_per_group, histograms,
+      base_(this,
+            max_sockets,
+            max_sockets_per_group,
+            histograms,
             ClientSocketPool::unused_idle_socket_timeout(),
             ClientSocketPool::used_idle_socket_timeout(),
-            new SSLConnectJobFactory(transport_pool,
-                                     socks_pool,
-                                     http_proxy_pool,
-                                     client_socket_factory,
-                                     host_resolver,
-                                     SSLClientSocketContext(
-                                         cert_verifier,
-                                         server_bound_cert_service,
-                                         transport_security_state,
-                                         cert_transparency_verifier,
-                                         ssl_session_cache_shard),
-                                     net_log)),
+            new SSLConnectJobFactory(
+                transport_pool,
+                socks_pool,
+                http_proxy_pool,
+                client_socket_factory,
+                host_resolver,
+                SSLClientSocketContext(cert_verifier,
+                                       server_bound_cert_service,
+                                       transport_security_state,
+                                       cert_transparency_verifier,
+                                       ssl_session_cache_shard),
+                net_log)),
       ssl_config_service_(ssl_config_service) {
   if (ssl_config_service_.get())
     ssl_config_service_->AddObserver(this);
   if (transport_pool_)
     base_.AddLowerLayeredPool(transport_pool_);
   if (socks_pool_)
     base_.AddLowerLayeredPool(socks_pool_);
   if (http_proxy_pool_)
     base_.AddLowerLayeredPool(http_proxy_pool_);
 }
 
 SSLClientSocketPool::~SSLClientSocketPool() {
   if (ssl_config_service_.get())
     ssl_config_service_->RemoveObserver(this);
 }
 
 scoped_ptr<ConnectJob>
 SSLClientSocketPool::SSLConnectJobFactory::NewConnectJob(
     const std::string& group_name,
     const PoolBase::Request& request,
     ConnectJob::Delegate* delegate) const {
-  return scoped_ptr<ConnectJob>(
-      new SSLConnectJob(group_name, request.priority(), request.params(),
-                        ConnectionTimeout(), transport_pool_, socks_pool_,
-                        http_proxy_pool_, client_socket_factory_,
-                        host_resolver_, context_, delegate, net_log_));
+  SSLConnectJobMessenger* messenger;
+  std::string cache_key = SSLClientSocket::FormatSessionCacheKey(
+      request.params()->host_and_port().ToString(),
+      context_.ssl_session_cache_shard);

[wtc, 2014/07/11 00:48:55]

Move the |cache_key| declaration into the if statement.

[mshelley, 2014/07/11 23:26:27]

Done.

+  if (SSLClientSocketPool::GetEnableConnectJobWaiting()) {
+    MessengerMap::const_iterator it = messenger_map_->find(cache_key);
+    if (it == messenger_map_->end()) {
+      std::pair<MessengerMap::iterator, bool> iter = messenger_map_->insert(
+          MessengerMap::value_type(cache_key, new SSLConnectJobMessenger()));
+      it = iter.first;
+    }
+    messenger = it->second;
+  } else {
+    messenger = NULL;

[wtc, 2014/07/11 00:48:54]

Nit: you can initialize |messager| to NULL on line 662 and delete this "else"
block.

[mshelley, 2014/07/11 23:26:27]

Done.

+  }
+
+  return scoped_ptr<ConnectJob>(new SSLConnectJob(group_name,
+                                                  request.priority(),
+                                                  request.params(),
+                                                  ConnectionTimeout(),
+                                                  transport_pool_,
+                                                  socks_pool_,
+                                                  http_proxy_pool_,
+                                                  client_socket_factory_,
+                                                  host_resolver_,
+                                                  context_,
+                                                  messenger,
+                                                  delegate,
+                                                  net_log_));
 }
 
 base::TimeDelta
 SSLClientSocketPool::SSLConnectJobFactory::ConnectionTimeout() const {
   return timeout_;
 }
 
 int SSLClientSocketPool::RequestSocket(const std::string& group_name,
                                        const void* socket_params,
                                        RequestPriority priority,
@@ skipping 98 matching lines @@
     HigherLayeredPool* higher_pool) {
   base_.RemoveHigherLayeredPool(higher_pool);
 }
 
 bool SSLClientSocketPool::CloseOneIdleConnection() {
   if (base_.CloseOneIdleSocket())
     return true;
   return base_.CloseOneIdleConnectionInHigherLayeredPool();
 }
 
+// static
+bool SSLClientSocketPool::enable_connect_job_waiting_ = false;

[wtc, 2014/07/11 00:48:55]

We usually initialize static data members before the constructor. (I don't think
the Style Guide has a recommendation for this.)

[mshelley, 2014/07/11 23:26:27]

Done.

+
+// static
+void SSLClientSocketPool::EnableConnectJobWaiting(bool enable) {
+  enable_connect_job_waiting_ = enable;
+}
+
+// static
+bool SSLClientSocketPool::GetEnableConnectJobWaiting() {
+  return enable_connect_job_waiting_;
+}
+
 void SSLClientSocketPool::OnSSLConfigChanged() {
   FlushWithError(ERR_NETWORK_CHANGED);
 }
 
 }  // namespace net