1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #include "google_apis/gcm/engine/connection_factory_impl.h"
7 #include "base/location.h"
8 #include "base/metrics/histogram.h"
9 #include "base/metrics/sparse_histogram.h"
10 #include "base/profiler/scoped_tracker.h"
11 #include "base/thread_task_runner_handle.h"
12 #include "google_apis/gcm/engine/connection_handler_impl.h"
13 #include "google_apis/gcm/monitoring/gcm_stats_recorder.h"
14 #include "google_apis/gcm/protocol/mcs.pb.h"
15 #include "net/base/load_flags.h"
16 #include "net/base/net_errors.h"
17 #include "net/http/http_network_session.h"
18 #include "net/http/http_request_headers.h"
19 #include "net/proxy/proxy_info.h"
20 #include "net/socket/client_socket_handle.h"
21 #include "net/socket/client_socket_pool_manager.h"
22 #include "net/ssl/ssl_config_service.h"
28 // The amount of time a Socket read should wait before timing out.
29 const int kReadTimeoutMs
= 30000; // 30 seconds.
31 // If a connection is reset after succeeding within this window of time,
32 // the previous backoff entry is restored (and the connection success is treated
33 // as if it was transient).
34 const int kConnectionResetWindowSecs
= 10; // 10 seconds.
36 // Decides whether the last login was within kConnectionResetWindowSecs of now
38 bool ShouldRestorePreviousBackoff(const base::TimeTicks
& login_time
,
39 const base::TimeTicks
& now_ticks
) {
40 return !login_time
.is_null() &&
41 now_ticks
- login_time
<=
42 base::TimeDelta::FromSeconds(kConnectionResetWindowSecs
);
47 ConnectionFactoryImpl::ConnectionFactoryImpl(
48 const std::vector
<GURL
>& mcs_endpoints
,
49 const net::BackoffEntry::Policy
& backoff_policy
,
50 const scoped_refptr
<net::HttpNetworkSession
>& gcm_network_session
,
51 const scoped_refptr
<net::HttpNetworkSession
>& http_network_session
,
53 GCMStatsRecorder
* recorder
)
54 : mcs_endpoints_(mcs_endpoints
),
56 last_successful_endpoint_(0),
57 backoff_policy_(backoff_policy
),
58 gcm_network_session_(gcm_network_session
),
59 http_network_session_(http_network_session
),
61 net::BoundNetLog::Make(net_log
, net::NetLog::SOURCE_SOCKET
)),
64 waiting_for_backoff_(false),
65 waiting_for_network_online_(false),
69 weak_ptr_factory_(this) {
70 DCHECK_GE(mcs_endpoints_
.size(), 1U);
71 DCHECK(!http_network_session_
.get() ||
72 (gcm_network_session_
.get() != http_network_session_
.get()));
75 ConnectionFactoryImpl::~ConnectionFactoryImpl() {
77 net::NetworkChangeNotifier::RemoveNetworkChangeObserver(this);
79 gcm_network_session_
->proxy_service()->CancelPacRequest(pac_request_
);
84 void ConnectionFactoryImpl::Initialize(
85 const BuildLoginRequestCallback
& request_builder
,
86 const ConnectionHandler::ProtoReceivedCallback
& read_callback
,
87 const ConnectionHandler::ProtoSentCallback
& write_callback
) {
88 DCHECK(!connection_handler_
);
89 DCHECK(read_callback_
.is_null());
90 DCHECK(write_callback_
.is_null());
92 previous_backoff_
= CreateBackoffEntry(&backoff_policy_
);
93 backoff_entry_
= CreateBackoffEntry(&backoff_policy_
);
94 request_builder_
= request_builder
;
95 read_callback_
= read_callback
;
96 write_callback_
= write_callback
;
98 net::NetworkChangeNotifier::AddNetworkChangeObserver(this);
99 waiting_for_network_online_
= net::NetworkChangeNotifier::IsOffline();
102 ConnectionHandler
* ConnectionFactoryImpl::GetConnectionHandler() const {
103 return connection_handler_
.get();
106 void ConnectionFactoryImpl::Connect() {
107 if (!connection_handler_
) {
108 connection_handler_
= CreateConnectionHandler(
109 base::TimeDelta::FromMilliseconds(kReadTimeoutMs
),
112 base::Bind(&ConnectionFactoryImpl::ConnectionHandlerCallback
,
113 weak_ptr_factory_
.GetWeakPtr())).Pass();
116 if (connecting_
|| waiting_for_backoff_
)
117 return; // Connection attempt already in progress or pending.
119 if (IsEndpointReachable())
120 return; // Already connected.
122 ConnectWithBackoff();
125 void ConnectionFactoryImpl::ConnectWithBackoff() {
126 // If a canary managed to connect while a backoff expiration was pending,
127 // just cleanup the internal state.
128 if (connecting_
|| logging_in_
|| IsEndpointReachable()) {
129 waiting_for_backoff_
= false;
133 if (backoff_entry_
->ShouldRejectRequest()) {
134 DVLOG(1) << "Delaying MCS endpoint connection for "
135 << backoff_entry_
->GetTimeUntilRelease().InMilliseconds()
137 waiting_for_backoff_
= true;
138 recorder_
->RecordConnectionDelayedDueToBackoff(
139 backoff_entry_
->GetTimeUntilRelease().InMilliseconds());
140 base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
142 base::Bind(&ConnectionFactoryImpl::ConnectWithBackoff
,
143 weak_ptr_factory_
.GetWeakPtr()),
144 backoff_entry_
->GetTimeUntilRelease());
148 DVLOG(1) << "Attempting connection to MCS endpoint.";
149 waiting_for_backoff_
= false;
150 // It's necessary to close the socket before attempting any new connection,
151 // otherwise it's possible to hit a use-after-free in the connection handler.
157 bool ConnectionFactoryImpl::IsEndpointReachable() const {
158 return connection_handler_
&& connection_handler_
->CanSendMessage();
161 std::string
ConnectionFactoryImpl::GetConnectionStateString() const {
162 if (IsEndpointReachable())
168 if (waiting_for_backoff_
)
169 return "WAITING FOR BACKOFF";
170 if (waiting_for_network_online_
)
171 return "WAITING FOR NETWORK CHANGE";
172 return "NOT CONNECTED";
175 void ConnectionFactoryImpl::SignalConnectionReset(
176 ConnectionResetReason reason
) {
177 if (!connection_handler_
) {
178 // No initial connection has been made. No need to do anything.
182 // A failure can trigger multiple resets, so no need to do anything if a
183 // connection is already in progress.
185 DVLOG(1) << "Connection in progress, ignoring reset.";
190 listener_
->OnDisconnected();
192 UMA_HISTOGRAM_ENUMERATION("GCM.ConnectionResetReason",
194 CONNECTION_RESET_COUNT
);
195 recorder_
->RecordConnectionResetSignaled(reason
);
196 if (!last_login_time_
.is_null()) {
197 UMA_HISTOGRAM_CUSTOM_TIMES("GCM.ConnectionUpTime",
198 NowTicks() - last_login_time_
,
199 base::TimeDelta::FromSeconds(1),
200 base::TimeDelta::FromHours(24),
202 // |last_login_time_| will be reset below, before attempting the new
207 DCHECK(!IsEndpointReachable());
209 // TODO(zea): if the network is offline, don't attempt to connect.
210 // See crbug.com/396687
212 // Network changes get special treatment as they can trigger a one-off canary
213 // request that bypasses backoff (but does nothing if a connection is in
214 // progress). Other connection reset events can be ignored as a connection
215 // is already awaiting backoff expiration.
216 if (waiting_for_backoff_
&& reason
!= NETWORK_CHANGE
) {
217 DVLOG(1) << "Backoff expiration pending, ignoring reset.";
221 if (reason
== NETWORK_CHANGE
) {
222 // Canary attempts bypass backoff without resetting it. These will have no
223 // effect if we're already in the process of connecting.
226 } else if (logging_in_
) {
227 // Failures prior to login completion just reuse the existing backoff entry.
229 backoff_entry_
->InformOfRequest(false);
230 } else if (reason
== LOGIN_FAILURE
||
231 ShouldRestorePreviousBackoff(last_login_time_
, NowTicks())) {
232 // Failures due to login, or within the reset window of a login, restore
233 // the backoff entry that was saved off at login completion time.
234 backoff_entry_
.swap(previous_backoff_
);
235 backoff_entry_
->InformOfRequest(false);
237 // We shouldn't be in backoff in thise case.
238 DCHECK_EQ(0, backoff_entry_
->failure_count());
241 // At this point the last login time has been consumed or deemed irrelevant,
243 last_login_time_
= base::TimeTicks();
248 void ConnectionFactoryImpl::SetConnectionListener(
249 ConnectionListener
* listener
) {
250 listener_
= listener
;
253 base::TimeTicks
ConnectionFactoryImpl::NextRetryAttempt() const {
255 return base::TimeTicks();
256 return backoff_entry_
->GetReleaseTime();
259 void ConnectionFactoryImpl::OnNetworkChanged(
260 net::NetworkChangeNotifier::ConnectionType type
) {
261 if (type
== net::NetworkChangeNotifier::CONNECTION_NONE
) {
262 DVLOG(1) << "Network lost, resettion connection.";
263 waiting_for_network_online_
= true;
265 // Will do nothing due to |waiting_for_network_online_ == true|.
266 // TODO(zea): make the above statement actually true. See crbug.com/396687
267 SignalConnectionReset(NETWORK_CHANGE
);
271 DVLOG(1) << "Connection type changed to " << type
<< ", reconnecting.";
272 waiting_for_network_online_
= false;
273 SignalConnectionReset(NETWORK_CHANGE
);
276 GURL
ConnectionFactoryImpl::GetCurrentEndpoint() const {
277 // Note that IsEndpointReachable() returns false anytime connecting_ is true,
278 // so while connecting this always uses |next_endpoint_|.
279 if (IsEndpointReachable())
280 return mcs_endpoints_
[last_successful_endpoint_
];
281 return mcs_endpoints_
[next_endpoint_
];
284 net::IPEndPoint
ConnectionFactoryImpl::GetPeerIP() {
285 if (!socket_handle_
.socket())
286 return net::IPEndPoint();
288 net::IPEndPoint ip_endpoint
;
289 int result
= socket_handle_
.socket()->GetPeerAddress(&ip_endpoint
);
290 if (result
!= net::OK
)
291 return net::IPEndPoint();
296 void ConnectionFactoryImpl::ConnectImpl() {
297 DCHECK(!IsEndpointReachable());
298 // TODO(zea): Make this a dcheck again. crbug.com/462319
299 CHECK(!socket_handle_
.socket());
301 // TODO(zea): if the network is offline, don't attempt to connect.
302 // See crbug.com/396687
305 GURL current_endpoint
= GetCurrentEndpoint();
306 recorder_
->RecordConnectionInitiated(current_endpoint
.host());
307 RebuildNetworkSessionAuthCache();
308 int status
= gcm_network_session_
->proxy_service()->ResolveProxy(
312 base::Bind(&ConnectionFactoryImpl::OnProxyResolveDone
,
313 weak_ptr_factory_
.GetWeakPtr()),
317 if (status
!= net::ERR_IO_PENDING
)
318 OnProxyResolveDone(status
);
321 void ConnectionFactoryImpl::InitHandler() {
322 // May be null in tests.
323 mcs_proto::LoginRequest login_request
;
324 if (!request_builder_
.is_null()) {
325 request_builder_
.Run(&login_request
);
326 DCHECK(login_request
.IsInitialized());
329 connection_handler_
->Init(login_request
, socket_handle_
.socket());
332 scoped_ptr
<net::BackoffEntry
> ConnectionFactoryImpl::CreateBackoffEntry(
333 const net::BackoffEntry::Policy
* const policy
) {
334 return scoped_ptr
<net::BackoffEntry
>(new net::BackoffEntry(policy
));
337 scoped_ptr
<ConnectionHandler
> ConnectionFactoryImpl::CreateConnectionHandler(
338 base::TimeDelta read_timeout
,
339 const ConnectionHandler::ProtoReceivedCallback
& read_callback
,
340 const ConnectionHandler::ProtoSentCallback
& write_callback
,
341 const ConnectionHandler::ConnectionChangedCallback
& connection_callback
) {
342 return make_scoped_ptr
<ConnectionHandler
>(
343 new ConnectionHandlerImpl(read_timeout
,
346 connection_callback
));
349 base::TimeTicks
ConnectionFactoryImpl::NowTicks() {
350 return base::TimeTicks::Now();
353 void ConnectionFactoryImpl::OnConnectDone(int result
) {
354 // TODO(zea): Remove ScopedTracker below once crbug.com/455884 is fixed.
355 tracked_objects::ScopedTracker
tracking_profile(
356 FROM_HERE_WITH_EXPLICIT_FUNCTION(
357 "455884 ConnectionFactoryImpl::OnConnectDone"));
358 if (result
!= net::OK
) {
359 // If the connection fails, try another proxy.
360 result
= ReconsiderProxyAfterError(result
);
361 // ReconsiderProxyAfterError either returns an error (in which case it is
362 // not reconsidering a proxy) or returns ERR_IO_PENDING if it is considering
364 DCHECK_NE(result
, net::OK
);
365 if (result
== net::ERR_IO_PENDING
)
366 return; // Proxy reconsideration pending. Return.
367 LOG(ERROR
) << "Failed to connect to MCS endpoint with error " << result
;
368 UMA_HISTOGRAM_BOOLEAN("GCM.ConnectionSuccessRate", false);
369 recorder_
->RecordConnectionFailure(result
);
371 backoff_entry_
->InformOfRequest(false);
372 UMA_HISTOGRAM_SPARSE_SLOWLY("GCM.ConnectionFailureErrorCode", result
);
374 // If there are other endpoints available, use the next endpoint on the
377 if (next_endpoint_
>= mcs_endpoints_
.size())
384 UMA_HISTOGRAM_BOOLEAN("GCM.ConnectionSuccessRate", true);
385 UMA_HISTOGRAM_COUNTS("GCM.ConnectionEndpoint", next_endpoint_
);
386 UMA_HISTOGRAM_BOOLEAN("GCM.ConnectedViaProxy",
387 !(proxy_info_
.is_empty() || proxy_info_
.is_direct()));
388 ReportSuccessfulProxyConnection();
389 recorder_
->RecordConnectionSuccess();
391 // Reset the endpoint back to the default.
392 // TODO(zea): consider prioritizing endpoints more intelligently based on
393 // which ones succeed most for this client? Although that will affect
394 // measuring the success rate of the default endpoint vs fallback.
395 last_successful_endpoint_
= next_endpoint_
;
399 DVLOG(1) << "MCS endpoint socket connection success, starting login.";
403 void ConnectionFactoryImpl::ConnectionHandlerCallback(int result
) {
404 DCHECK(!connecting_
);
405 if (result
!= net::OK
) {
406 // TODO(zea): Consider how to handle errors that may require some sort of
407 // user intervention (login page, etc.).
408 UMA_HISTOGRAM_SPARSE_SLOWLY("GCM.ConnectionDisconnectErrorCode", result
);
409 SignalConnectionReset(SOCKET_FAILURE
);
413 // Handshake complete, reset backoff. If the login failed with an error,
414 // the client should invoke SignalConnectionReset(LOGIN_FAILURE), which will
415 // restore the previous backoff.
416 DVLOG(1) << "Handshake complete.";
417 last_login_time_
= NowTicks();
418 previous_backoff_
.swap(backoff_entry_
);
419 backoff_entry_
->Reset();
423 listener_
->OnConnected(GetCurrentEndpoint(), GetPeerIP());
426 // This has largely been copied from
427 // HttpStreamFactoryImpl::Job::DoResolveProxyComplete. This should be
428 // refactored into some common place.
429 void ConnectionFactoryImpl::OnProxyResolveDone(int status
) {
431 DVLOG(1) << "Proxy resolution status: " << status
;
433 DCHECK_NE(status
, net::ERR_IO_PENDING
);
434 if (status
== net::OK
) {
435 // Remove unsupported proxies from the list.
436 proxy_info_
.RemoveProxiesWithoutScheme(
437 net::ProxyServer::SCHEME_DIRECT
|
438 net::ProxyServer::SCHEME_HTTP
| net::ProxyServer::SCHEME_HTTPS
|
439 net::ProxyServer::SCHEME_SOCKS4
| net::ProxyServer::SCHEME_SOCKS5
);
441 if (proxy_info_
.is_empty()) {
442 // No proxies/direct to choose from. This happens when we don't support
443 // any of the proxies in the returned list.
444 status
= net::ERR_NO_SUPPORTED_PROXIES
;
448 if (status
!= net::OK
) {
449 // Failed to resolve proxy. Retry later.
450 OnConnectDone(status
);
454 DVLOG(1) << "Resolved proxy with PAC:" << proxy_info_
.ToPacString();
456 net::SSLConfig ssl_config
;
457 gcm_network_session_
->ssl_config_service()->GetSSLConfig(&ssl_config
);
458 status
= net::InitSocketHandleForTlsConnect(
459 net::HostPortPair::FromURL(GetCurrentEndpoint()),
460 gcm_network_session_
.get(),
464 net::PRIVACY_MODE_DISABLED
,
467 base::Bind(&ConnectionFactoryImpl::OnConnectDone
,
468 weak_ptr_factory_
.GetWeakPtr()));
469 if (status
!= net::ERR_IO_PENDING
)
470 OnConnectDone(status
);
473 // This has largely been copied from
474 // HttpStreamFactoryImpl::Job::ReconsiderProxyAfterError. This should be
475 // refactored into some common place.
476 // This method reconsiders the proxy on certain errors. If it does reconsider
477 // a proxy it always returns ERR_IO_PENDING and posts a call to
478 // OnProxyResolveDone with the result of the reconsideration.
479 int ConnectionFactoryImpl::ReconsiderProxyAfterError(int error
) {
480 DCHECK(!pac_request_
);
481 DCHECK_NE(error
, net::OK
);
482 DCHECK_NE(error
, net::ERR_IO_PENDING
);
483 // A failure to resolve the hostname or any error related to establishing a
484 // TCP connection could be grounds for trying a new proxy configuration.
486 // Why do this when a hostname cannot be resolved? Some URLs only make sense
487 // to proxy servers. The hostname in those URLs might fail to resolve if we
488 // are still using a non-proxy config. We need to check if a proxy config
489 // now exists that corresponds to a proxy server that could load the URL.
492 case net::ERR_PROXY_CONNECTION_FAILED
:
493 case net::ERR_NAME_NOT_RESOLVED
:
494 case net::ERR_INTERNET_DISCONNECTED
:
495 case net::ERR_ADDRESS_UNREACHABLE
:
496 case net::ERR_CONNECTION_CLOSED
:
497 case net::ERR_CONNECTION_TIMED_OUT
:
498 case net::ERR_CONNECTION_RESET
:
499 case net::ERR_CONNECTION_REFUSED
:
500 case net::ERR_CONNECTION_ABORTED
:
501 case net::ERR_TIMED_OUT
:
502 case net::ERR_TUNNEL_CONNECTION_FAILED
:
503 case net::ERR_SOCKS_CONNECTION_FAILED
:
504 // This can happen in the case of trying to talk to a proxy using SSL, and
505 // ending up talking to a captive portal that supports SSL instead.
506 case net::ERR_PROXY_CERTIFICATE_INVALID
:
507 // This can happen when trying to talk SSL to a non-SSL server (Like a
509 case net::ERR_SSL_PROTOCOL_ERROR
:
511 case net::ERR_SOCKS_CONNECTION_HOST_UNREACHABLE
:
512 // Remap the SOCKS-specific "host unreachable" error to a more
513 // generic error code (this way consumers like the link doctor
514 // know to substitute their error page).
516 // Note that if the host resolving was done by the SOCKS5 proxy, we can't
517 // differentiate between a proxy-side "host not found" versus a proxy-side
518 // "address unreachable" error, and will report both of these failures as
519 // ERR_ADDRESS_UNREACHABLE.
520 return net::ERR_ADDRESS_UNREACHABLE
;
525 net::SSLConfig ssl_config
;
526 gcm_network_session_
->ssl_config_service()->GetSSLConfig(&ssl_config
);
527 if (proxy_info_
.is_https() && ssl_config
.send_client_cert
) {
528 gcm_network_session_
->ssl_client_auth_cache()->Remove(
529 proxy_info_
.proxy_server().host_port_pair());
532 int status
= gcm_network_session_
->proxy_service()->ReconsiderProxyAfterError(
533 GetCurrentEndpoint(), net::LOAD_NORMAL
, error
, &proxy_info_
,
534 base::Bind(&ConnectionFactoryImpl::OnProxyResolveDone
,
535 weak_ptr_factory_
.GetWeakPtr()),
539 if (status
== net::OK
|| status
== net::ERR_IO_PENDING
) {
542 // If ReconsiderProxyAfterError() failed synchronously, it means
543 // there was nothing left to fall-back to, so fail the transaction
544 // with the last connection error we got.
548 // If there is new proxy info, post OnProxyResolveDone to retry it. Otherwise,
549 // if there was an error falling back, fail synchronously.
550 if (status
== net::OK
) {
551 base::ThreadTaskRunnerHandle::Get()->PostTask(
553 base::Bind(&ConnectionFactoryImpl::OnProxyResolveDone
,
554 weak_ptr_factory_
.GetWeakPtr(), status
));
555 status
= net::ERR_IO_PENDING
;
560 void ConnectionFactoryImpl::ReportSuccessfulProxyConnection() {
561 if (gcm_network_session_
.get() && gcm_network_session_
->proxy_service())
562 gcm_network_session_
->proxy_service()->ReportSuccess(proxy_info_
, NULL
);
565 void ConnectionFactoryImpl::CloseSocket() {
566 // The connection handler needs to be reset, else it'll attempt to keep using
567 // the destroyed socket.
568 if (connection_handler_
)
569 connection_handler_
->Reset();
571 if (socket_handle_
.socket() && socket_handle_
.socket()->IsConnected())
572 socket_handle_
.socket()->Disconnect();
573 socket_handle_
.Reset();
576 void ConnectionFactoryImpl::RebuildNetworkSessionAuthCache() {
577 if (!http_network_session_
.get() || !http_network_session_
->http_auth_cache())
580 gcm_network_session_
->http_auth_cache()->UpdateAllFrom(
581 *http_network_session_
->http_auth_cache());