/* vim:set ts=4 sw=4 sts=4 et cin: */ /* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ #ifndef nsHttpConnectionMgr_h__ #define nsHttpConnectionMgr_h__ #include "nsHttpConnection.h" #include "nsHttpTransaction.h" #include "nsTArray.h" #include "nsThreadUtils.h" #include "nsClassHashtable.h" #include "nsDataHashtable.h" #include "nsAutoPtr.h" #include "mozilla/ReentrantMonitor.h" #include "mozilla/TimeStamp.h" #include "mozilla/Attributes.h" #include "nsIObserver.h" #include "nsITimer.h" class nsIHttpUpgradeListener; namespace mozilla { namespace net { class EventTokenBucket; struct HttpRetParams; //----------------------------------------------------------------------------- class nsHttpConnectionMgr : public nsIObserver { public: NS_DECL_THREADSAFE_ISUPPORTS NS_DECL_NSIOBSERVER // parameter names enum nsParamName { MAX_CONNECTIONS, MAX_PERSISTENT_CONNECTIONS_PER_HOST, MAX_PERSISTENT_CONNECTIONS_PER_PROXY, MAX_REQUEST_DELAY, MAX_PIPELINED_REQUESTS, MAX_OPTIMISTIC_PIPELINED_REQUESTS }; //------------------------------------------------------------------------- // NOTE: functions below may only be called on the main thread. //------------------------------------------------------------------------- nsHttpConnectionMgr(); nsresult Init(uint16_t maxConnections, uint16_t maxPersistentConnectionsPerHost, uint16_t maxPersistentConnectionsPerProxy, uint16_t maxRequestDelay, uint16_t maxPipelinedRequests, uint16_t maxOptimisticPipelinedRequests); nsresult Shutdown(); //------------------------------------------------------------------------- // NOTE: functions below may be called on any thread. //------------------------------------------------------------------------- // Schedules next pruning of dead connection to happen after // given time. void PruneDeadConnectionsAfter(uint32_t time); // Stops timer scheduled for next pruning of dead connections if // there are no more idle connections or active spdy ones void ConditionallyStopPruneDeadConnectionsTimer(); // Stops timer used for the read timeout tick if there are no currently // active connections. void ConditionallyStopTimeoutTick(); // adds a transaction to the list of managed transactions. nsresult AddTransaction(nsHttpTransaction *, int32_t priority); // called to reschedule the given transaction. it must already have been // added to the connection manager via AddTransaction. nsresult RescheduleTransaction(nsHttpTransaction *, int32_t priority); // cancels a transaction w/ the given reason. nsresult CancelTransaction(nsHttpTransaction *, nsresult reason); // called to force the connection manager to prune its list of idle // connections. nsresult PruneDeadConnections(); // Close all idle persistent connections and prevent any active connections // from being reused. Optional connection info resets CI specific // information such as Happy Eyeballs history. nsresult DoShiftReloadConnectionCleanup(nsHttpConnectionInfo *); // called to get a reference to the socket transport service. the socket // transport service is not available when the connection manager is down. nsresult GetSocketThreadTarget(nsIEventTarget **); // called to indicate a transaction for the connectionInfo is likely coming // soon. The connection manager may use this information to start a TCP // and/or SSL level handshake for that resource immediately so that it is // ready when the transaction is submitted. No obligation is taken on by the // connection manager, nor is the submitter obligated to actually submit a // real transaction for this connectionInfo. nsresult SpeculativeConnect(nsHttpConnectionInfo *, nsIInterfaceRequestor *, uint32_t caps = 0); // called when a connection is done processing a transaction. if the // connection can be reused then it will be added to the idle list, else // it will be closed. nsresult ReclaimConnection(nsHttpConnection *conn); // called by the main thread to execute the taketransport() logic on the // socket thread after a 101 response has been received and the socket // needs to be transferred to an expectant upgrade listener such as // websockets. nsresult CompleteUpgrade(nsAHttpConnection *aConn, nsIHttpUpgradeListener *aUpgradeListener); // called to update a parameter after the connection manager has already // been initialized. nsresult UpdateParam(nsParamName name, uint16_t value); // called from main thread to post a new request token bucket // to the socket thread nsresult UpdateRequestTokenBucket(EventTokenBucket *aBucket); // Pipielining Interfaces and Datatypes const static uint32_t kPipelineInfoTypeMask = 0xffff0000; const static uint32_t kPipelineInfoIDMask = ~kPipelineInfoTypeMask; const static uint32_t kPipelineInfoTypeRed = 0x00010000; const static uint32_t kPipelineInfoTypeBad = 0x00020000; const static uint32_t kPipelineInfoTypeNeutral = 0x00040000; const static uint32_t kPipelineInfoTypeGood = 0x00080000; enum PipelineFeedbackInfoType { // Used when an HTTP response less than 1.1 is received RedVersionTooLow = kPipelineInfoTypeRed | kPipelineInfoTypeBad | 0x0001, // Used when a HTTP Server response header that is on the banned from // pipelining list is received RedBannedServer = kPipelineInfoTypeRed | kPipelineInfoTypeBad | 0x0002, // Used when a response is terminated early, when it fails an // integrity check such as assoc-req or when a 304 contained a Last-Modified // differnet than the entry being validated. RedCorruptedContent = kPipelineInfoTypeRed | kPipelineInfoTypeBad | 0x0004, // Used when a pipeline is only partly satisfied - for instance if the // server closed the connection after responding to the first // request but left some requests unprocessed. RedCanceledPipeline = kPipelineInfoTypeRed | kPipelineInfoTypeBad | 0x0005, // Used when a connection that we expected to stay persistently open // was closed by the server. Not used when simply timed out. BadExplicitClose = kPipelineInfoTypeBad | 0x0003, // Used when there is a gap of around 400 - 1200ms in between data being // read from the server BadSlowReadMinor = kPipelineInfoTypeBad | 0x0006, // Used when there is a gap of > 1200ms in between data being // read from the server BadSlowReadMajor = kPipelineInfoTypeBad | 0x0007, // Used when a response is received that is not framed with either chunked // encoding or a complete content length. BadInsufficientFraming = kPipelineInfoTypeBad | 0x0008, // Used when a very large response is recevied in a potential pipelining // context. Large responses cause head of line blocking. BadUnexpectedLarge = kPipelineInfoTypeBad | 0x000B, // Used when a response is received that has headers that appear to support // pipelining. NeutralExpectedOK = kPipelineInfoTypeNeutral | 0x0009, // Used when a response is received successfully to a pipelined request. GoodCompletedOK = kPipelineInfoTypeGood | 0x000A }; // called to provide information relevant to the pipelining manager // may be called from any thread void PipelineFeedbackInfo(nsHttpConnectionInfo *, PipelineFeedbackInfoType info, nsHttpConnection *, uint32_t); void ReportFailedToProcess(nsIURI *uri); // Causes a large amount of connection diagnostic information to be // printed to the javascript console void PrintDiagnostics(); //------------------------------------------------------------------------- // NOTE: functions below may be called only on the socket thread. //------------------------------------------------------------------------- // called to force the transaction queue to be processed once more, giving // preference to the specified connection. nsresult ProcessPendingQ(nsHttpConnectionInfo *); bool ProcessPendingQForEntry(nsHttpConnectionInfo *); // Try and process all pending transactions nsresult ProcessPendingQ(); // This is used to force an idle connection to be closed and removed from // the idle connection list. It is called when the idle connection detects // that the network peer has closed the transport. nsresult CloseIdleConnection(nsHttpConnection *); // The connection manager needs to know when a normal HTTP connection has been // upgraded to SPDY because the dispatch and idle semantics are a little // bit different. void ReportSpdyConnection(nsHttpConnection *, bool usingSpdy); // A spdy server can supply cwnd information for the session that is used // in future sessions to speed up the opening portions of the connection. void ReportSpdyCWNDSetting(nsHttpConnectionInfo *host, uint32_t cwndValue); uint32_t GetSpdyCWNDSetting(nsHttpConnectionInfo *host); bool SupportsPipelining(nsHttpConnectionInfo *); bool GetConnectionData(nsTArray *); void ResetIPFamilyPreference(nsHttpConnectionInfo *); private: virtual ~nsHttpConnectionMgr(); enum PipeliningState { // Host has proven itself pipeline capable through past experience and // large pipeline depths are allowed on multiple connections. PS_GREEN, // Not enough information is available yet with this host to be certain // of pipeline capability. Small pipelines on a single connection are // allowed in order to decide whether or not to proceed to green. PS_YELLOW, // One or more bad events has happened that indicate that pipelining // to this host (or a particular type of transaction with this host) // is a bad idea. Pipelining is not currently allowed, but time and // other positive experiences will eventually allow it to try again. PS_RED }; class nsHalfOpenSocket; // nsConnectionEntry // // mCT maps connection info hash key to nsConnectionEntry object, which // contains list of active and idle connections as well as the list of // pending transactions. // class nsConnectionEntry { public: nsConnectionEntry(nsHttpConnectionInfo *ci); ~nsConnectionEntry(); nsHttpConnectionInfo *mConnInfo; nsTArray mPendingQ; // pending transaction queue nsTArray mActiveConns; // active connections nsTArray mIdleConns; // idle persistent connections nsTArray mHalfOpens; // half open connections // calculate the number of half open sockets that have not had at least 1 // connection complete uint32_t UnconnectedHalfOpens(); // Remove a particular half open socket from the mHalfOpens array void RemoveHalfOpen(nsHalfOpenSocket *); // Pipeline depths for various states const static uint32_t kPipelineUnlimited = 1024; // fully open - extended green const static uint32_t kPipelineOpen = 6; // 6 on each conn - normal green const static uint32_t kPipelineRestricted = 2; // 2 on just 1 conn in yellow nsHttpConnectionMgr::PipeliningState PipelineState(); void OnPipelineFeedbackInfo( nsHttpConnectionMgr::PipelineFeedbackInfoType info, nsHttpConnection *, uint32_t); bool SupportsPipelining(); uint32_t MaxPipelineDepth(nsAHttpTransaction::Classifier classification); void CreditPenalty(); nsHttpConnectionMgr::PipeliningState mPipelineState; void SetYellowConnection(nsHttpConnection *); void OnYellowComplete(); uint32_t mYellowGoodEvents; uint32_t mYellowBadEvents; nsHttpConnection *mYellowConnection; // initialGreenDepth is the max depth of a pipeline when you first // transition to green. Normally this is kPipelineOpen, but it can // be kPipelineUnlimited in aggressive mode. uint32_t mInitialGreenDepth; // greenDepth is the current max allowed depth of a pipeline when // in the green state. Normally this starts as kPipelineOpen and // grows to kPipelineUnlimited after a pipeline of depth 3 has been // successfully transacted. uint32_t mGreenDepth; // pipeliningPenalty is the current amount of penalty points this host // entry has earned for participating in events that are not conducive // to good pipelines - such as head of line blocking, canceled pipelines, // etc.. penalties are paid back either through elapsed time or simply // healthy transactions. Having penalty points means that this host is // not currently eligible for pipelines. int16_t mPipeliningPenalty; // some penalty points only apply to particular classifications of // transactions - this allows a server that perhaps has head of line // blocking problems on CGI queries to still serve JS pipelined. int16_t mPipeliningClassPenalty[nsAHttpTransaction::CLASS_MAX]; // for calculating penalty repair credits TimeStamp mLastCreditTime; // Spdy sometimes resolves the address in the socket manager in order // to re-coalesce sharded HTTP hosts. The dotted decimal address is // combined with the Anonymous flag from the connection information // to build the hash key for hosts in the same ip pool. // // When a set of hosts are coalesced together one of them is marked // mSpdyPreferred. The mapping is maintained in the connection mananger // mSpdyPreferred hash. // nsCString mCoalescingKey; // The value of a recevied SPDY settings type 5 previously received // for this connection entry and the time it was set. uint32_t mSpdyCWND; TimeStamp mSpdyCWNDTimeStamp; // To have the UsingSpdy flag means some host with the same connection // entry has done NPN=spdy/* at some point. It does not mean every // connection is currently using spdy. bool mUsingSpdy; // mTestedSpdy is set after NPN negotiation has occurred and we know // with confidence whether a host speaks spdy or not (which is reflected // in mUsingSpdy). Before mTestedSpdy is set, handshake parallelism is // minimized so that we can multiplex on a single spdy connection. bool mTestedSpdy; bool mSpdyPreferred; // Flags to remember our happy-eyeballs decision. // Reset only by Ctrl-F5 reload. // True when we've first connected an IPv4 server for this host, // initially false. bool mPreferIPv4 : 1; // True when we've first connected an IPv6 server for this host, // initially false. bool mPreferIPv6 : 1; // Set the IP family preference flags according the connected family void RecordIPFamilyPreference(uint16_t family); // Resets all flags to their default values void ResetIPFamilyPreference(); }; // nsConnectionHandle // // thin wrapper around a real connection, used to keep track of references // to the connection to determine when the connection may be reused. the // transaction (or pipeline) owns a reference to this handle. this extra // layer of indirection greatly simplifies consumer code, avoiding the // need for consumer code to know when to give the connection back to the // connection manager. // class nsConnectionHandle : public nsAHttpConnection { public: NS_DECL_THREADSAFE_ISUPPORTS NS_DECL_NSAHTTPCONNECTION(mConn) nsConnectionHandle(nsHttpConnection *conn) { NS_ADDREF(mConn = conn); } virtual ~nsConnectionHandle(); nsHttpConnection *mConn; }; // nsHalfOpenSocket is used to hold the state of an opening TCP socket // while we wait for it to establish and bind it to a connection class nsHalfOpenSocket MOZ_FINAL : public nsIOutputStreamCallback, public nsITransportEventSink, public nsIInterfaceRequestor, public nsITimerCallback { public: NS_DECL_THREADSAFE_ISUPPORTS NS_DECL_NSIOUTPUTSTREAMCALLBACK NS_DECL_NSITRANSPORTEVENTSINK NS_DECL_NSIINTERFACEREQUESTOR NS_DECL_NSITIMERCALLBACK nsHalfOpenSocket(nsConnectionEntry *ent, nsAHttpTransaction *trans, uint32_t caps); ~nsHalfOpenSocket(); nsresult SetupStreams(nsISocketTransport **, nsIAsyncInputStream **, nsIAsyncOutputStream **, bool isBackup); nsresult SetupPrimaryStreams(); nsresult SetupBackupStreams(); void SetupBackupTimer(); void CancelBackupTimer(); void Abandon(); double Duration(TimeStamp epoch); nsISocketTransport *SocketTransport() { return mSocketTransport; } nsISocketTransport *BackupTransport() { return mBackupTransport; } nsAHttpTransaction *Transaction() { return mTransaction; } bool IsSpeculative() { return mSpeculative; } void SetSpeculative(bool val) { mSpeculative = val; } bool HasConnected() { return mHasConnected; } void PrintDiagnostics(nsCString &log); private: nsConnectionEntry *mEnt; nsRefPtr mTransaction; nsCOMPtr mSocketTransport; nsCOMPtr mStreamOut; nsCOMPtr mStreamIn; uint32_t mCaps; // mSpeculative is set if the socket was created from // SpeculativeConnect(). It is cleared when a transaction would normally // start a new connection from scratch but instead finds this one in // the half open list and claims it for its own use. (which due to // the vagaries of scheduling from the pending queue might not actually // match up - but it prevents a speculative connection from opening // more connections that are needed.) bool mSpeculative; TimeStamp mPrimarySynStarted; TimeStamp mBackupSynStarted; // for syn retry nsCOMPtr mSynTimer; nsCOMPtr mBackupTransport; nsCOMPtr mBackupStreamOut; nsCOMPtr mBackupStreamIn; bool mHasConnected; }; friend class nsHalfOpenSocket; //------------------------------------------------------------------------- // NOTE: these members may be accessed from any thread (use mReentrantMonitor) //------------------------------------------------------------------------- ReentrantMonitor mReentrantMonitor; nsCOMPtr mSocketThreadTarget; // connection limits uint16_t mMaxConns; uint16_t mMaxPersistConnsPerHost; uint16_t mMaxPersistConnsPerProxy; uint16_t mMaxRequestDelay; // in seconds uint16_t mMaxPipelinedRequests; uint16_t mMaxOptimisticPipelinedRequests; bool mIsShuttingDown; //------------------------------------------------------------------------- // NOTE: these members are only accessed on the socket transport thread //------------------------------------------------------------------------- static PLDHashOperator ProcessOneTransactionCB(const nsACString &, nsAutoPtr &, void *); static PLDHashOperator ProcessAllTransactionsCB(const nsACString &, nsAutoPtr &, void *); static PLDHashOperator PruneDeadConnectionsCB(const nsACString &, nsAutoPtr &, void *); static PLDHashOperator ShutdownPassCB(const nsACString &, nsAutoPtr &, void *); static PLDHashOperator PurgeExcessIdleConnectionsCB(const nsACString &, nsAutoPtr &, void *); static PLDHashOperator PurgeExcessSpdyConnectionsCB(const nsACString &, nsAutoPtr &, void *); static PLDHashOperator ClosePersistentConnectionsCB(const nsACString &, nsAutoPtr &, void *); bool ProcessPendingQForEntry(nsConnectionEntry *, bool considerAll); bool IsUnderPressure(nsConnectionEntry *ent, nsHttpTransaction::Classifier classification); bool AtActiveConnectionLimit(nsConnectionEntry *, uint32_t caps); nsresult TryDispatchTransaction(nsConnectionEntry *ent, bool onlyReusedConnection, nsHttpTransaction *trans); nsresult DispatchTransaction(nsConnectionEntry *, nsHttpTransaction *, nsHttpConnection *); nsresult DispatchAbstractTransaction(nsConnectionEntry *, nsAHttpTransaction *, uint32_t, nsHttpConnection *, int32_t); nsresult BuildPipeline(nsConnectionEntry *, nsAHttpTransaction *, nsHttpPipeline **); bool RestrictConnections(nsConnectionEntry *, bool = false); nsresult ProcessNewTransaction(nsHttpTransaction *); nsresult EnsureSocketThreadTarget(); void ClosePersistentConnections(nsConnectionEntry *ent); void ReportProxyTelemetry(nsConnectionEntry *ent); nsresult CreateTransport(nsConnectionEntry *, nsAHttpTransaction *, uint32_t, bool); void AddActiveConn(nsHttpConnection *, nsConnectionEntry *); void DecrementActiveConnCount(nsHttpConnection *); void StartedConnect(); void RecvdConnect(); nsConnectionEntry *GetOrCreateConnectionEntry(nsHttpConnectionInfo *); nsresult MakeNewConnection(nsConnectionEntry *ent, nsHttpTransaction *trans); bool AddToShortestPipeline(nsConnectionEntry *ent, nsHttpTransaction *trans, nsHttpTransaction::Classifier classification, uint16_t depthLimit); // Manage the preferred spdy connection entry for this address nsConnectionEntry *GetSpdyPreferredEnt(nsConnectionEntry *aOriginalEntry); void RemoveSpdyPreferredEnt(nsACString &aDottedDecimal); nsHttpConnection *GetSpdyPreferredConn(nsConnectionEntry *ent); nsDataHashtable mSpdyPreferredHash; nsConnectionEntry *LookupConnectionEntry(nsHttpConnectionInfo *ci, nsHttpConnection *conn, nsHttpTransaction *trans); void ProcessSpdyPendingQ(nsConnectionEntry *ent); static PLDHashOperator ProcessSpdyPendingQCB( const nsACString &key, nsAutoPtr &ent, void *closure); // message handlers have this signature typedef void (nsHttpConnectionMgr:: *nsConnEventHandler)(int32_t, void *); // nsConnEvent // // subclass of nsRunnable used to marshall events to the socket transport // thread. this class is used to implement PostEvent. // class nsConnEvent; friend class nsConnEvent; class nsConnEvent : public nsRunnable { public: nsConnEvent(nsHttpConnectionMgr *mgr, nsConnEventHandler handler, int32_t iparam, void *vparam) : mMgr(mgr) , mHandler(handler) , mIParam(iparam) , mVParam(vparam) { NS_ADDREF(mMgr); } NS_IMETHOD Run() { (mMgr->*mHandler)(mIParam, mVParam); return NS_OK; } private: virtual ~nsConnEvent() { NS_RELEASE(mMgr); } nsHttpConnectionMgr *mMgr; nsConnEventHandler mHandler; int32_t mIParam; void *mVParam; }; nsresult PostEvent(nsConnEventHandler handler, int32_t iparam = 0, void *vparam = nullptr); // message handlers void OnMsgShutdown (int32_t, void *); void OnMsgShutdownConfirm (int32_t, void *); void OnMsgNewTransaction (int32_t, void *); void OnMsgReschedTransaction (int32_t, void *); void OnMsgCancelTransaction (int32_t, void *); void OnMsgProcessPendingQ (int32_t, void *); void OnMsgPruneDeadConnections (int32_t, void *); void OnMsgSpeculativeConnect (int32_t, void *); void OnMsgReclaimConnection (int32_t, void *); void OnMsgCompleteUpgrade (int32_t, void *); void OnMsgUpdateParam (int32_t, void *); void OnMsgDoShiftReloadConnectionCleanup (int32_t, void *); void OnMsgProcessFeedback (int32_t, void *); void OnMsgProcessAllSpdyPendingQ (int32_t, void *); void OnMsgUpdateRequestTokenBucket (int32_t, void *); // Total number of active connections in all of the ConnectionEntry objects // that are accessed from mCT connection table. uint16_t mNumActiveConns; // Total number of idle connections in all of the ConnectionEntry objects // that are accessed from mCT connection table. uint16_t mNumIdleConns; // Total number of spdy connections which are a subset of the active conns uint16_t mNumSpdyActiveConns; // Total number of connections in mHalfOpens ConnectionEntry objects // that are accessed from mCT connection table uint32_t mNumHalfOpenConns; // Holds time in seconds for next wake-up to prune dead connections. uint64_t mTimeOfNextWakeUp; // Timer for next pruning of dead connections. nsCOMPtr mTimer; // A 1s tick to call nsHttpConnection::ReadTimeoutTick on // active http/1 connections and check for orphaned half opens. // Disabled when there are no active or half open connections. nsCOMPtr mTimeoutTick; bool mTimeoutTickArmed; uint32_t mTimeoutTickNext; // // the connection table // // this table is indexed by connection key. each entry is a // nsConnectionEntry object. It is unlocked and therefore must only // be accessed from the socket thread. // nsClassHashtable mCT; static PLDHashOperator ReadConnectionEntry(const nsACString &key, nsAutoPtr &ent, void *aArg); // Read Timeout Tick handlers void ActivateTimeoutTick(); void TimeoutTick(); static PLDHashOperator TimeoutTickCB(const nsACString &key, nsAutoPtr &ent, void *closure); // For diagnostics void OnMsgPrintDiagnostics(int32_t, void *); static PLDHashOperator PrintDiagnosticsCB(const nsACString &key, nsAutoPtr &ent, void *closure); nsCString mLogData; }; }} // namespace mozilla::net #endif // !nsHttpConnectionMgr_h__