blob: 8f3505a76b79613d0e950290233b48217c6e9503 [file] [log] [blame]
// Copyright (c) 2011 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.
#pragma once
#include <deque>
#include <list>
#include <map>
#include <queue>
#include <string>
#include "base/gtest_prod_util.h"
#include "base/memory/linked_ptr.h"
#include "base/memory/ref_counted.h"
#include "base/task.h"
#include "net/base/io_buffer.h"
#include "net/base/load_states.h"
#include "net/base/net_errors.h"
#include "net/base/net_log.h"
#include "net/base/request_priority.h"
#include "net/base/ssl_config_service.h"
#include "net/base/upload_data_stream.h"
#include "net/socket/client_socket_handle.h"
#include "net/socket/stream_socket.h"
#include "net/spdy/spdy_framer.h"
#include "net/spdy/spdy_io_buffer.h"
#include "net/spdy/spdy_protocol.h"
#include "net/spdy/spdy_session_pool.h"
namespace net {
// This is somewhat arbitrary and not really fixed, but it will always work
// reasonably with ethernet. Chop the world into 2-packet chunks. This is
// somewhat arbitrary, but is reasonably small and ensures that we elicit
// ACKs quickly from TCP (because TCP tries to only ACK every other packet).
const int kMss = 1430;
const int kMaxSpdyFrameChunkSize = (2 * kMss) - spdy::SpdyFrame::size();
class BoundNetLog;
class SpdySettingsStorage;
class SpdyStream;
class SSLInfo;
class NET_EXPORT SpdySession : public base::RefCounted<SpdySession>,
public spdy::SpdyFramerVisitorInterface {
// Create a new SpdySession.
// |host_port_proxy_pair| is the host/port that this session connects to, and
// the proxy configuration settings that it's using.
// |spdy_session_pool| is the SpdySessionPool that owns us. Its lifetime must
// strictly be greater than |this|.
// |session| is the HttpNetworkSession. |net_log| is the NetLog that we log
// network events to.
SpdySession(const HostPortProxyPair& host_port_proxy_pair,
SpdySessionPool* spdy_session_pool,
SpdySettingsStorage* spdy_settings,
bool verify_domain_authentication,
NetLog* net_log);
const HostPortPair& host_port_pair() const {
return host_port_proxy_pair_.first;
const HostPortProxyPair& host_port_proxy_pair() const {
return host_port_proxy_pair_;
// Get a pushed stream for a given |url|.
// If the server initiates a stream, it might already exist for a given path.
// The server might also not have initiated the stream yet, but indicated it
// will via X-Associated-Content. Writes the stream out to |spdy_stream|.
// Returns a net error code.
int GetPushStream(
const GURL& url,
scoped_refptr<SpdyStream>* spdy_stream,
const BoundNetLog& stream_net_log);
// Create a new stream for a given |url|. Writes it out to |spdy_stream|.
// Returns a net error code, possibly ERR_IO_PENDING.
int CreateStream(
const GURL& url,
RequestPriority priority,
scoped_refptr<SpdyStream>* spdy_stream,
const BoundNetLog& stream_net_log,
OldCompletionCallback* callback);
// Remove PendingCreateStream objects on transaction deletion
void CancelPendingCreateStreams(const scoped_refptr<SpdyStream>* spdy_stream);
// Used by SpdySessionPool to initialize with a pre-existing SSL socket. For
// testing, setting is_secure to false allows initialization with a
// pre-existing TCP socket.
// Returns OK on success, or an error on failure.
net::Error InitializeWithSocket(ClientSocketHandle* connection,
bool is_secure,
int certificate_error_code);
// Check to see if this SPDY session can support an additional domain.
// If the session is un-authenticated, then this call always returns true.
// For SSL-based sessions, verifies that the certificate in use by this
// session provides authentication for the domain.
// NOTE: This function can have false negatives on some platforms.
bool VerifyDomainAuthentication(const std::string& domain);
// Send the SYN frame for |stream_id|. This also sends PING message to check
// the status of the connection.
int WriteSynStream(
spdy::SpdyStreamId stream_id,
RequestPriority priority,
spdy::SpdyControlFlags flags,
const linked_ptr<spdy::SpdyHeaderBlock>& headers);
// Write a data frame to the stream.
// Used to create and queue a data frame for the given stream.
int WriteStreamData(spdy::SpdyStreamId stream_id, net::IOBuffer* data,
int len,
spdy::SpdyDataFlags flags);
// Close a stream.
void CloseStream(spdy::SpdyStreamId stream_id, int status);
// Reset a stream by sending a RST_STREAM frame with given status code.
// Also closes the stream. Was not piggybacked to CloseStream since not
// all of the calls to CloseStream necessitate sending a RST_STREAM.
void ResetStream(spdy::SpdyStreamId stream_id, spdy::SpdyStatusCodes status);
// Check if a stream is active.
bool IsStreamActive(spdy::SpdyStreamId stream_id) const;
// The LoadState is used for informing the user of the current network
// status, such as "resolving host", "connecting", etc.
LoadState GetLoadState() const;
// Fills SSL info in |ssl_info| and returns true when SSL is in use.
bool GetSSLInfo(SSLInfo* ssl_info, bool* was_npn_negotiated);
// Fills SSL Certificate Request info |cert_request_info| and returns
// true when SSL is in use.
bool GetSSLCertRequestInfo(SSLCertRequestInfo* cert_request_info);
// Enable or disable SSL.
static void SetSSLMode(bool enable) { use_ssl_ = enable; }
static bool SSLMode() { return use_ssl_; }
// Enable or disable flow control.
static void set_flow_control(bool enable) { use_flow_control_ = enable; }
static bool flow_control() { return use_flow_control_; }
// Sets the max concurrent streams per session, as a ceiling on any server
// specific SETTINGS value.
static void set_max_concurrent_streams(size_t value) {
max_concurrent_stream_limit_ = value;
static size_t max_concurrent_streams() {
return max_concurrent_stream_limit_;
// Enable sending of PING frame with each request.
static void set_enable_ping_based_connection_checking(bool enable) {
enable_ping_based_connection_checking_ = enable;
static bool enable_ping_based_connection_checking() {
return enable_ping_based_connection_checking_;
// The initial max concurrent streams per session, can be overridden by the
// server via SETTINGS.
static void set_init_max_concurrent_streams(size_t value) {
init_max_concurrent_streams_ =
std::min(value, max_concurrent_stream_limit_);
// Send WINDOW_UPDATE frame, called by a stream whenever receive window
// size is increased.
void SendWindowUpdate(spdy::SpdyStreamId stream_id, int delta_window_size);
// If session is closed, no new streams/transactions should be created.
bool IsClosed() const { return state_ == CLOSED; }
// Closes this session. This will close all active streams and mark
// the session as permanently closed.
// |err| should not be OK; this function is intended to be called on
// error.
// |remove_from_pool| indicates whether to also remove the session from the
// session pool.
void CloseSessionOnError(net::Error err, bool remove_from_pool);
// Retrieves information on the current state of the SPDY session as a
// Value. Caller takes possession of the returned value.
base::Value* GetInfoAsValue() const;
// Indicates whether the session is being reused after having successfully
// used to send/receive data in the past.
bool IsReused() const {
return frames_received_ > 0;
// Returns true if the underlying transport socket ever had any reads or
// writes.
bool WasEverUsed() const {
return connection_->socket()->WasEverUsed();
void set_spdy_session_pool(SpdySessionPool* pool) {
spdy_session_pool_ = NULL;
// Returns true if session is not currently active
bool is_active() const {
return !active_streams_.empty();
// Access to the number of active and pending streams. These are primarily
// available for testing and diagnostics.
size_t num_active_streams() const { return active_streams_.size(); }
size_t num_unclaimed_pushed_streams() const {
return unclaimed_pushed_streams_.size();
const BoundNetLog& net_log() const { return net_log_; }
int GetPeerAddress(AddressList* address) const;
int GetLocalAddress(IPEndPoint* address) const;
friend class base::RefCounted<SpdySession>;
// Allow tests to access our innards for testing purposes.
FRIEND_TEST_ALL_PREFIXES(SpdySessionTest, FailedPing);
FRIEND_TEST_ALL_PREFIXES(SpdySessionTest, GetActivePushStream);
struct PendingCreateStream {
PendingCreateStream(const GURL& url, RequestPriority priority,
scoped_refptr<SpdyStream>* spdy_stream,
const BoundNetLog& stream_net_log,
OldCompletionCallback* callback)
: url(&url), priority(priority), spdy_stream(spdy_stream),
stream_net_log(&stream_net_log), callback(callback) { }
const GURL* url;
RequestPriority priority;
scoped_refptr<SpdyStream>* spdy_stream;
const BoundNetLog* stream_net_log;
OldCompletionCallback* callback;
typedef std::queue<PendingCreateStream, std::list< PendingCreateStream> >
typedef std::map<int, scoped_refptr<SpdyStream> > ActiveStreamMap;
// Only HTTP push a stream.
typedef std::map<std::string, scoped_refptr<SpdyStream> > PushedStreamMap;
typedef std::priority_queue<SpdyIOBuffer> OutputQueue;
struct CallbackResultPair {
CallbackResultPair() : callback(NULL), result(OK) {}
CallbackResultPair(OldCompletionCallback* callback_in, int result_in)
: callback(callback_in), result(result_in) {}
OldCompletionCallback* callback;
int result;
typedef std::map<const scoped_refptr<SpdyStream>*, CallbackResultPair>
enum State {
virtual ~SpdySession();
void ProcessPendingCreateStreams();
int CreateStreamImpl(
const GURL& url,
RequestPriority priority,
scoped_refptr<SpdyStream>* spdy_stream,
const BoundNetLog& stream_net_log);
// Control frame handlers.
void OnSyn(const spdy::SpdySynStreamControlFrame& frame,
const linked_ptr<spdy::SpdyHeaderBlock>& headers);
void OnSynReply(const spdy::SpdySynReplyControlFrame& frame,
const linked_ptr<spdy::SpdyHeaderBlock>& headers);
void OnHeaders(const spdy::SpdyHeadersControlFrame& frame,
const linked_ptr<spdy::SpdyHeaderBlock>& headers);
void OnRst(const spdy::SpdyRstStreamControlFrame& frame);
void OnGoAway(const spdy::SpdyGoAwayControlFrame& frame);
void OnPing(const spdy::SpdyPingControlFrame& frame);
void OnSettings(const spdy::SpdySettingsControlFrame& frame);
void OnWindowUpdate(const spdy::SpdyWindowUpdateControlFrame& frame);
// IO Callbacks
void OnReadComplete(int result);
void OnWriteComplete(int result);
// Send relevant SETTINGS. This is generally called on connection setup.
void SendSettings();
// Handle SETTINGS. Either when we send settings, or when we receive a
// SETTINGS ontrol frame, update our SpdySession accordingly.
void HandleSettings(const spdy::SpdySettings& settings);
// Send the PING (preface-PING and trailing-PING) frames.
void SendPrefacePingIfNoneInFlight();
// Send PING if there are no PINGs in flight and we haven't heard from server.
void SendPrefacePing();
// Send a PING after delay. Don't post a PING if there is already
// a trailing PING pending.
void PlanToSendTrailingPing();
// Send a PING if there is no |trailing_ping_pending_|. This PING verifies
// that the requests are being received by the server.
void SendTrailingPing();
// Send the PING frame.
void WritePingFrame(uint32 unique_id);
// Post a CheckPingStatus call after delay. Don't post if there is already
// CheckPingStatus running.
void PlanToCheckPingStatus();
// Check the status of the connection. It calls |CloseSessionOnError| if we
// haven't received any data in |kHungInterval| time period.
void CheckPingStatus(base::TimeTicks last_check_time);
// Start reading from the socket.
// Returns OK on success, or an error on failure.
net::Error ReadSocket();
// Write current data to the socket.
void WriteSocketLater();
void WriteSocket();
// Get a new stream id.
int GetNewStreamId();
// Queue a frame for sending.
// |frame| is the frame to send.
// |priority| is the priority for insertion into the queue.
// |stream| is the stream which this IO is associated with (or NULL).
void QueueFrame(spdy::SpdyFrame* frame, spdy::SpdyPriority priority,
SpdyStream* stream);
// Track active streams in the active stream list.
void ActivateStream(SpdyStream* stream);
void DeleteStream(spdy::SpdyStreamId id, int status);
// Removes this session from the session pool.
void RemoveFromPool();
// Check if we have a pending pushed-stream for this url
// Returns the stream if found (and returns it from the pending
// list), returns NULL otherwise.
scoped_refptr<SpdyStream> GetActivePushStream(const std::string& url);
// Calls OnResponseReceived().
// Returns true if successful.
bool Respond(const spdy::SpdyHeaderBlock& headers,
const scoped_refptr<SpdyStream> stream);
void RecordPingRTTHistogram(base::TimeDelta duration);
void RecordHistograms();
// Closes all streams. Used as part of shutdown.
void CloseAllStreams(net::Error status);
// Invokes a user callback for stream creation. We provide this method so it
// can be deferred to the MessageLoop, so we avoid re-entrancy problems.
void InvokeUserStreamCreationCallback(scoped_refptr<SpdyStream>* stream);
// SpdyFramerVisitorInterface:
virtual void OnError(spdy::SpdyFramer*);
virtual void OnStreamFrameData(spdy::SpdyStreamId stream_id,
const char* data,
size_t len);
virtual void OnControl(const spdy::SpdyControlFrame* frame);
virtual bool OnControlFrameHeaderData(spdy::SpdyStreamId stream_id,
const char* header_data,
size_t len);
virtual void OnDataFrameHeader(const spdy::SpdyDataFrame* frame);
// --------------------------
// Helper methods for testing
// --------------------------
static void set_connection_at_risk_of_loss_ms(int duration) {
connection_at_risk_of_loss_ms_ = duration;
static int connection_at_risk_of_loss_ms() {
return connection_at_risk_of_loss_ms_;
static void set_trailing_ping_delay_time_ms(int duration) {
trailing_ping_delay_time_ms_ = duration;
static int trailing_ping_delay_time_ms() {
return trailing_ping_delay_time_ms_;
static void set_hung_interval_ms(int duration) {
hung_interval_ms_ = duration;
static int hung_interval_ms() {
return hung_interval_ms_;
int64 pings_in_flight() const { return pings_in_flight_; }
uint32 next_ping_id() const { return next_ping_id_; }
base::TimeTicks received_data_time() const { return received_data_time_; }
bool trailing_ping_pending() const { return trailing_ping_pending_; }
bool check_ping_status_pending() const { return check_ping_status_pending_; }
// Callbacks for the Spdy session.
OldCompletionCallbackImpl<SpdySession> read_callback_;
OldCompletionCallbackImpl<SpdySession> write_callback_;
// Used for posting asynchronous IO tasks. We use this even though
// SpdySession is refcounted because we don't need to keep the SpdySession
// alive if the last reference is within a RunnableMethod. Just revoke the
// method.
ScopedRunnableMethodFactory<SpdySession> method_factory_;
// Map of the SpdyStreams for which we have a pending Task to invoke a
// callback. This is necessary since, before we invoke said callback, it's
// possible that the request is cancelled.
PendingCallbackMap pending_callback_map_;
// The domain this session is connected to.
const HostPortProxyPair host_port_proxy_pair_;
// |spdy_session_pool_| owns us, therefore its lifetime must exceed ours. We
// set this to NULL after we are removed from the pool.
SpdySessionPool* spdy_session_pool_;
SpdySettingsStorage* const spdy_settings_;
// The socket handle for this session.
scoped_ptr<ClientSocketHandle> connection_;
// The read buffer used to read data from the socket.
scoped_refptr<IOBuffer> read_buffer_;
bool read_pending_;
int stream_hi_water_mark_; // The next stream id to use.
// Queue, for each priority, of pending Create Streams that have not
// yet been satisfied
PendingCreateStreamQueue create_stream_queues_[NUM_PRIORITIES];
// Map from stream id to all active streams. Streams are active in the sense
// that they have a consumer (typically SpdyNetworkTransaction and regardless
// of whether or not there is currently any ongoing IO [might be waiting for
// the server to start pushing the stream]) or there are still network events
// incoming even though the consumer has already gone away (cancellation).
// TODO(willchan): Perhaps we should separate out cancelled streams and move
// them into a separate ActiveStreamMap, and not deliver network events to
// them?
ActiveStreamMap active_streams_;
// Map of all the streams that have already started to be pushed by the
// server, but do not have consumers yet.
PushedStreamMap unclaimed_pushed_streams_;
// As we gather data to be sent, we put it into the output queue.
OutputQueue queue_;
// The packet we are currently sending.
bool write_pending_; // Will be true when a write is in progress.
SpdyIOBuffer in_flight_write_; // This is the write buffer in progress.
// Flag if we have a pending message scheduled for WriteSocket.
bool delayed_write_pending_;
// Flag if we're using an SSL connection for this SpdySession.
bool is_secure_;
// Certificate error code when using a secure connection.
int certificate_error_code_;
// Spdy Frame state.
spdy::SpdyFramer spdy_framer_;
// If an error has occurred on the session, the session is effectively
// dead. Record this error here. When no error has occurred, |error_| will
// be OK.
net::Error error_;
State state_;
// Limits
size_t max_concurrent_streams_; // 0 if no limit
// Some statistics counters for the session.
int streams_initiated_count_;
int streams_pushed_count_;
int streams_pushed_and_claimed_count_;
int streams_abandoned_count_;
int frames_received_;
int bytes_received_;
bool sent_settings_; // Did this session send settings when it started.
bool received_settings_; // Did this session receive at least one settings
// frame.
int stalled_streams_; // Count of streams that were ever stalled.
// Count of all pings on the wire, for which we have not gotten a response.
int64 pings_in_flight_;
// This is the next ping_id (unique_id) to be sent in PING frame.
uint32 next_ping_id_;
// This is the last time we have sent a PING.
base::TimeTicks last_ping_sent_time_;
// This is the last time we have received data.
base::TimeTicks received_data_time_;
// Indicate if we have already scheduled a delayed task to send a trailing
// ping (and we never have more than one scheduled at a time).
bool trailing_ping_pending_;
// Indicate if we have already scheduled a delayed task to check the ping
// status.
bool check_ping_status_pending_;
// Indicate if we need to send a ping (generally, a trailing ping). This helps
// us to decide if we need yet another trailing ping, or if it would be a
// waste of effort (and MUST not be done).
bool need_to_send_ping_;
// Initial send window size for the session; can be changed by an
// arriving SETTINGS frame; newly created streams use this value for the
// initial send window size.
int initial_send_window_size_;
// Initial receive window size for the session; there are plans to add a
// command line switch that would cause a SETTINGS frame with window size
// announcement to be sent on startup; newly created streams will use
// this value for the initial receive window size.
int initial_recv_window_size_;
BoundNetLog net_log_;
// Outside of tests, this should always be true.
bool verify_domain_authentication_;
static bool use_ssl_;
static bool use_flow_control_;
static size_t init_max_concurrent_streams_;
static size_t max_concurrent_stream_limit_;
// This enables or disables connection health checking system.
static bool enable_ping_based_connection_checking_;
// |connection_at_risk_of_loss_ms_| is an optimization to avoid sending
// wasteful preface pings (when we just got some data).
// If it is zero (the most conservative figure), then we always send the
// preface ping (when none are in flight).
// It is common for TCP/IP sessions to time out in about 3-5 minutes.
// Certainly if it has been more than 3 minutes, we do want to send a preface
// ping.
// We don't think any connection will time out in under about 10 seconds. So
// this might as well be set to something conservative like 10 seconds. Later,
// we could adjust it to send fewer pings perhaps.
static int connection_at_risk_of_loss_ms_;
// This is the amount of time (in milliseconds) we wait before sending a
// trailing ping. We use a trailing ping (sent after all data) to get an
// effective acknowlegement from the server that it has indeed received all
// (prior) data frames. With that assurance, we are willing to enter into a
// wait state for responses to our last data frame(s) without further pings.
static int trailing_ping_delay_time_ms_;
// The amount of time (in milliseconds) that we are willing to tolerate with
// no data received (of any form), while there is a ping in flight, before we
// declare the connection to be hung.
static int hung_interval_ms_;
class NetLogSpdySynParameter : public NetLog::EventParameters {
NetLogSpdySynParameter(const linked_ptr<spdy::SpdyHeaderBlock>& headers,
spdy::SpdyControlFlags flags,
spdy::SpdyStreamId id,
spdy::SpdyStreamId associated_stream);
const linked_ptr<spdy::SpdyHeaderBlock>& GetHeaders() const {
return headers_;
virtual base::Value* ToValue() const;
virtual ~NetLogSpdySynParameter();
const linked_ptr<spdy::SpdyHeaderBlock> headers_;
const spdy::SpdyControlFlags flags_;
const spdy::SpdyStreamId id_;
const spdy::SpdyStreamId associated_stream_;
} // namespace net