| // Copyright (c) 2018 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. |
| #ifndef QUICHE_QUIC_CORE_QUIC_STREAM_ID_MANAGER_H_ |
| #define QUICHE_QUIC_CORE_QUIC_STREAM_ID_MANAGER_H_ |
| |
| #include "net/third_party/quiche/src/quic/core/frames/quic_frame.h" |
| #include "net/third_party/quiche/src/quic/core/quic_types.h" |
| #include "net/third_party/quiche/src/quic/core/quic_versions.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_logging.h" |
| #include "net/third_party/quiche/src/quic/platform/api/quic_str_cat.h" |
| |
| namespace quic { |
| |
| namespace test { |
| class QuicSessionPeer; |
| class QuicStreamIdManagerPeer; |
| } // namespace test |
| |
| class QuicSession; |
| |
| // Amount to increment a stream ID value to get the next stream ID in |
| // the stream ID space. |
| const QuicStreamId kV99StreamIdIncrement = 4; |
| |
| // This constant controls the size of the window when deciding whether |
| // to generate a MAX_STREAMS frame or not. See the discussion of the |
| // window, below, for more details. |
| const int kMaxStreamsWindowDivisor = 2; |
| |
| // This class manages the stream ids for Version 99/IETF QUIC. |
| class QUIC_EXPORT_PRIVATE QuicStreamIdManager { |
| public: |
| QuicStreamIdManager(QuicSession* session, |
| bool unidirectional, |
| QuicStreamCount max_allowed_outgoing_streams, |
| QuicStreamCount max_allowed_incoming_streams); |
| |
| ~QuicStreamIdManager(); |
| |
| // Generate a string suitable for sending to the log/etc to show current state |
| // of the stream ID manager. |
| std::string DebugString() const { |
| return QuicStrCat( |
| " { unidirectional_: ", unidirectional_, |
| ", perspective: ", perspective(), |
| ", outgoing_max_streams_: ", outgoing_max_streams_, |
| ", next_outgoing_stream_id_: ", next_outgoing_stream_id_, |
| ", outgoing_stream_count_: ", outgoing_stream_count_, |
| ", outgoing_static_stream_count_: ", outgoing_static_stream_count_, |
| ", using_default_max_streams_: ", using_default_max_streams_, |
| ", incoming_actual_max_streams_: ", incoming_actual_max_streams_, |
| ", incoming_advertised_max_streams_: ", |
| incoming_advertised_max_streams_, |
| ", incoming_static_stream_count_: ", incoming_static_stream_count_, |
| ", incoming_stream_count_: ", incoming_stream_count_, |
| ", available_streams_.size(): ", available_streams_.size(), |
| ", largest_peer_created_stream_id_: ", largest_peer_created_stream_id_, |
| ", max_streams_window_: ", max_streams_window_, " }"); |
| } |
| |
| // Processes the MAX_STREAMS frame, invoked from |
| // QuicSession::OnMaxStreamsFrame. It has the same semantics as the |
| // QuicFramerVisitorInterface, returning true if the framer should continue |
| // processing the packet, false if not. |
| bool OnMaxStreamsFrame(const QuicMaxStreamsFrame& frame); |
| |
| // Processes the STREAMS_BLOCKED frame, invoked from |
| // QuicSession::OnStreamsBlockedFrame. It has the same semantics as the |
| // QuicFramerVisitorInterface, returning true if the framer should continue |
| // processing the packet, false if not. |
| bool OnStreamsBlockedFrame(const QuicStreamsBlockedFrame& frame); |
| |
| // Indicates whether the next outgoing stream ID can be allocated or not. |
| bool CanOpenNextOutgoingStream(); |
| |
| // Generate and send a MAX_STREAMS frame. |
| void SendMaxStreamsFrame(); |
| |
| // Invoked to deal with releasing a stream. Does nothing if the stream is |
| // outgoing. If the stream is incoming, the number of streams that the peer |
| // can open will be updated and a MAX_STREAMS frame, informing the peer of |
| // the additional streams, may be sent. |
| void OnStreamClosed(QuicStreamId stream_id); |
| |
| // Returns the next outgoing stream id. Applications must call |
| // CanOpenNextOutgoingStream() first. A QUIC_BUG is logged if this method |
| // allocates a stream ID past the peer specified limit. |
| QuicStreamId GetNextOutgoingStreamId(); |
| |
| // Set the outgoing stream limits to be |max_open_streams| plus the number |
| // of static streams that have been opened. For outgoing and incoming, |
| // respectively. |
| // SetMaxOpenOutgoingStreams will QUIC_BUG if it is called after |
| // a MAX_STREAMS frame has been received. |
| // TODO(fkastenholz): When static streams disappear, these should be removed. |
| void SetMaxOpenOutgoingStreams(size_t max_open_streams); |
| void SetMaxOpenIncomingStreams(size_t max_open_streams); |
| |
| // Adjust the outgoing stream limit - max_open_streams is the limit, not |
| // including static streams. Does not QUIC_BUG if it is called _after_ |
| // receiving a MAX_STREAMS. |
| void AdjustMaxOpenOutgoingStreams(size_t max_open_streams); |
| |
| // Sets the maximum number of outgoing streams to max_open_streams. |
| // Used when configuration has been done and we have an initial |
| // maximum stream count from the peer. Note that if the stream count is such |
| // that it would result in stream ID values that are greater than the |
| // implementation limit, it pegs the count at the implementation limit. |
| bool ConfigureMaxOpenOutgoingStreams(size_t max_open_streams); |
| |
| // Register a new stream as a static stream. This is used so that the |
| // advertised MAX STREAMS can be calculated based on the start of the |
| // dynamic stream space. This method will take any stream ID, one that either |
| // this node or the peer will initiate. |
| // Returns false if this fails because the new static stream would cause the |
| // stream limit to be exceeded. |
| bool RegisterStaticStream(QuicStreamId stream_id); |
| |
| // Checks if the incoming stream ID exceeds the MAX_STREAMS limit. If the |
| // limit is exceeded, closes the connection and returns false. Uses the |
| // actual maximium, not the most recently advertised value, in order to |
| // enforce the Google-QUIC number of open streams behavior. |
| // This method should be called exactly once for each incoming stream |
| // creation. |
| bool MaybeIncreaseLargestPeerStreamId(const QuicStreamId stream_id); |
| |
| // Returns true if |id| is still available. |
| bool IsAvailableStream(QuicStreamId id) const; |
| |
| // Return true if given stream is peer initiated. |
| bool IsIncomingStream(QuicStreamId id) const; |
| |
| size_t outgoing_static_stream_count() const { |
| return outgoing_static_stream_count_; |
| } |
| |
| size_t incoming_initial_max_open_streams() const { |
| return incoming_initial_max_open_streams_; |
| } |
| |
| QuicStreamCount max_streams_window() const { return max_streams_window_; } |
| |
| QuicStreamId next_outgoing_stream_id() const { |
| return next_outgoing_stream_id_; |
| } |
| |
| // Number of streams that the peer believes that it can still create. |
| size_t available_incoming_streams(); |
| |
| void set_largest_peer_created_stream_id( |
| QuicStreamId largest_peer_created_stream_id) { |
| largest_peer_created_stream_id_ = largest_peer_created_stream_id; |
| } |
| |
| // These are the limits for outgoing and incoming streams, |
| // respectively. For incoming there are two limits, what has |
| // been advertised to the peer and what is actually available. |
| // The advertised incoming amount should never be more than the actual |
| // incoming one. |
| QuicStreamCount outgoing_max_streams() const { return outgoing_max_streams_; } |
| QuicStreamCount incoming_actual_max_streams() const { |
| return incoming_actual_max_streams_; |
| } |
| QuicStreamCount incoming_advertised_max_streams() const { |
| return incoming_advertised_max_streams_; |
| } |
| // Number of streams that have been opened (including those that have been |
| // opened and then closed. Must never exceed outgoing_max_streams |
| QuicStreamCount outgoing_stream_count() { return outgoing_stream_count_; } |
| |
| // Perspective (CLIENT/SERVER) of this node and the peer, respectively. |
| Perspective perspective() const; |
| Perspective peer_perspective() const; |
| |
| QuicTransportVersion transport_version() const; |
| |
| private: |
| friend class test::QuicSessionPeer; |
| friend class test::QuicStreamIdManagerPeer; |
| |
| // Check whether the MAX_STREAMS window has opened up enough and, if so, |
| // generate and send a MAX_STREAMS frame. |
| void MaybeSendMaxStreamsFrame(); |
| |
| // Get what should be the first incoming/outgoing stream ID that |
| // this stream id manager will manage, taking into account directionality and |
| // client/server perspective. |
| QuicStreamId GetFirstOutgoingStreamId() const; |
| QuicStreamId GetFirstIncomingStreamId() const; |
| |
| void CalculateIncomingMaxStreamsWindow(); |
| |
| // Back reference to the session containing this Stream ID Manager. |
| // needed to access various session methods, such as perspective() |
| QuicSession* session_; |
| |
| // Whether this stream id manager is for unidrectional (true) or bidirectional |
| // (false) streams. |
| bool unidirectional_; |
| |
| // This is the number of streams that this node can initiate. |
| // This limit applies to both static and dynamic streams - the total |
| // of the two can not exceed this count. |
| // This limit is: |
| // - Initiated to a value specified in the constructor |
| // - May be updated when the config is received. |
| // - Is updated whenever a MAX STREAMS frame is received. |
| QuicStreamCount outgoing_max_streams_; |
| |
| // The ID to use for the next outgoing stream. |
| QuicStreamId next_outgoing_stream_id_; |
| |
| // The number of outgoing streams that have ever been opened, including those |
| // that have been closed. This number must never be larger than |
| // outgoing_max_streams_. |
| QuicStreamCount outgoing_stream_count_; |
| |
| // Number of outgoing static streams created. |
| // TODO(fkastenholz): Remove when static streams no longer supported for IETF |
| // QUIC. |
| QuicStreamCount outgoing_static_stream_count_; |
| |
| // Set to true while the default (from the constructor) outgoing stream limit |
| // is in use. It is set to false when either a MAX STREAMS frame is received |
| // or the transport negotiation completes and sets the stream limit (this is |
| // equivalent to a MAX_STREAMS frame). |
| // Necessary because outgoing_max_streams_ is a "best guess" |
| // until we receive an authoritative value from the peer. |
| // outgoing_max_streams_ is initialized in the constructor |
| // to some hard-coded value, which may or may not be consistent |
| // with what the peer wants. Furthermore, as we create outgoing |
| // static streams, the cap raises as static streams get inserted |
| // "beneath" the dynamic streams because, prior to receiving |
| // a MAX_STREAMS, the values setting the limit are interpreted |
| // as "number of request/responses" that can be created. Once |
| // a MAX_STREAMS is received, it becomes a hard limit. |
| bool using_default_max_streams_; |
| |
| // FOR INCOMING STREAMS |
| |
| // The maximum number of streams that can be opened by the peer. |
| QuicStreamCount incoming_actual_max_streams_; |
| QuicStreamCount incoming_advertised_max_streams_; |
| |
| // Initial maximum on the number of open streams allowed. |
| QuicStreamCount incoming_initial_max_open_streams_; |
| |
| // Number of outgoing static streams created. |
| // TODO(fkastenholz): Remove when static streams no longer supported for IETF |
| // QUIC. |
| QuicStreamCount incoming_static_stream_count_; |
| |
| // This is the number of streams that have been created -- some are still |
| // open, the others have been closed. It is the number that is compared |
| // against MAX_STREAMS when deciding whether to accept a new stream or not. |
| QuicStreamCount incoming_stream_count_; |
| |
| // Set of stream ids that are less than the largest stream id that has been |
| // received, but are nonetheless available to be created. |
| QuicUnorderedSet<QuicStreamId> available_streams_; |
| |
| QuicStreamId largest_peer_created_stream_id_; |
| |
| // When incoming streams close the local node sends MAX_STREAMS frames. It |
| // does so only when the peer can open fewer than |max_stream_id_window_| |
| // streams. That is, when |incoming_actual_max_streams_| - |
| // |incoming_advertised_max_streams_| is less than the window. |
| // max_streams_window_ is set to 1/2 of the initial number of incoming streams |
| // that are allowed (as set in the constructor). |
| QuicStreamId max_streams_window_; |
| }; |
| } // namespace quic |
| |
| #endif // QUICHE_QUIC_CORE_QUIC_STREAM_ID_MANAGER_H_ |