| // Copyright 2016 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_HTTP2_DECODER_HTTP2_FRAME_DECODER_LISTENER_H_ |
| #define QUICHE_HTTP2_DECODER_HTTP2_FRAME_DECODER_LISTENER_H_ |
| |
| // Http2FrameDecoderListener is the interface which the HTTP/2 decoder uses |
| // to report the decoded frames to a listener. |
| // |
| // The general design is to assume that the listener will copy the data it needs |
| // (e.g. frame headers) and will keep track of the implicit state of the |
| // decoding process (i.e. the decoder maintains just the information it needs in |
| // order to perform the decoding). Therefore, the parameters are just those with |
| // (potentially) new data, not previously provided info about the current frame. |
| // |
| // The calls are described as if they are made in quick succession, i.e. one |
| // after another, but of course the decoder needs input to decode, and the |
| // decoder will only call the listener once the necessary input has been |
| // provided. For example: OnDataStart can only be called once the 9 bytes of |
| // of an HTTP/2 common frame header have been received. The decoder will call |
| // the listener methods as soon as possible to avoid almost all buffering. |
| // |
| // The listener interface is designed so that it is possible to exactly |
| // reconstruct the serialized frames, with the exception of reserved bits, |
| // including in the frame header's flags and stream_id fields, which will have |
| // been cleared before the methods below are called. |
| |
| #include <stddef.h> |
| |
| #include <cstdint> |
| #include <type_traits> |
| |
| #include "net/third_party/quiche/src/http2/http2_constants.h" |
| #include "net/third_party/quiche/src/http2/http2_structures.h" |
| |
| namespace http2 { |
| |
| // TODO(jamessynge): Consider sorting the methods by frequency of call, if that |
| // helps at all. |
| class Http2FrameDecoderListener { |
| public: |
| Http2FrameDecoderListener() {} |
| virtual ~Http2FrameDecoderListener() {} |
| |
| // Called once the common frame header has been decoded for any frame, and |
| // before any of the methods below, which will also be called. This method is |
| // included in this interface only for the purpose of supporting SpdyFramer |
| // semantics via an adapter. This is the only method that has a non-void |
| // return type, and this is just so that Http2FrameDecoderAdapter (called |
| // from SpdyFramer) can more readily pass existing tests that expect decoding |
| // to stop if the headers alone indicate an error. Return false to stop |
| // decoding just after decoding the header, else return true to continue |
| // decoding. |
| // TODO(jamessynge): Remove OnFrameHeader once done with supporting |
| // SpdyFramer's exact states. |
| virtual bool OnFrameHeader(const Http2FrameHeader& header) = 0; |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| |
| // Called once the common frame header has been decoded for a DATA frame, |
| // before examining the frame's payload, after which: |
| // OnPadLength will be called if header.IsPadded() is true, i.e. if the |
| // PADDED flag is set; |
| // OnDataPayload will be called as the non-padding portion of the payload |
| // is available until all of it has been provided; |
| // OnPadding will be called if the frame is padded AND the Pad Length field |
| // is greater than zero; |
| // OnDataEnd will be called last. If the frame is unpadded and has no |
| // payload, then this will be called immediately after OnDataStart. |
| virtual void OnDataStart(const Http2FrameHeader& header) = 0; |
| |
| // Called when the next non-padding portion of a DATA frame's payload is |
| // received. |
| // |data| The start of |len| bytes of data. |
| // |len| The length of the data buffer. Maybe zero in some cases, which does |
| // not mean anything special. |
| virtual void OnDataPayload(const char* data, size_t len) = 0; |
| |
| // Called after an entire DATA frame has been received. |
| // If header.IsEndStream() == true, this is the last data for the stream. |
| virtual void OnDataEnd() = 0; |
| |
| // Called once the common frame header has been decoded for a HEADERS frame, |
| // before examining the frame's payload, after which: |
| // OnPadLength will be called if header.IsPadded() is true, i.e. if the |
| // PADDED flag is set; |
| // OnHeadersPriority will be called if header.HasPriority() is true, i.e. if |
| // the frame has the PRIORITY flag; |
| // OnHpackFragment as the remainder of the non-padding payload is available |
| // until all if has been provided; |
| // OnPadding will be called if the frame is padded AND the Pad Length field |
| // is greater than zero; |
| // OnHeadersEnd will be called last; If the frame is unpadded and has no |
| // payload, then this will be called immediately after OnHeadersStart; |
| // OnHeadersEnd indicates the end of the HPACK block only if the frame |
| // header had the END_HEADERS flag set, else the END_HEADERS should be |
| // looked for on a subsequent CONTINUATION frame. |
| virtual void OnHeadersStart(const Http2FrameHeader& header) = 0; |
| |
| // Called when a HEADERS frame is received with the PRIORITY flag set and |
| // the priority fields have been decoded. |
| virtual void OnHeadersPriority( |
| const Http2PriorityFields& priority_fields) = 0; |
| |
| // Called when a fragment (i.e. some or all of an HPACK Block) is received; |
| // this may be part of a HEADERS, PUSH_PROMISE or CONTINUATION frame. |
| // |data| The start of |len| bytes of data. |
| // |len| The length of the data buffer. Maybe zero in some cases, which does |
| // not mean anything special, except that it simplified the decoder. |
| virtual void OnHpackFragment(const char* data, size_t len) = 0; |
| |
| // Called after an entire HEADERS frame has been received. The frame is the |
| // end of the HEADERS if the END_HEADERS flag is set; else there should be |
| // CONTINUATION frames after this frame. |
| virtual void OnHeadersEnd() = 0; |
| |
| // Called when an entire PRIORITY frame has been decoded. |
| virtual void OnPriorityFrame(const Http2FrameHeader& header, |
| const Http2PriorityFields& priority_fields) = 0; |
| |
| // Called once the common frame header has been decoded for a CONTINUATION |
| // frame, before examining the frame's payload, after which: |
| // OnHpackFragment as the frame's payload is available until all of it |
| // has been provided; |
| // OnContinuationEnd will be called last; If the frame has no payload, |
| // then this will be called immediately after OnContinuationStart; |
| // the HPACK block is at an end if and only if the frame header passed |
| // to OnContinuationStart had the END_HEADERS flag set. |
| virtual void OnContinuationStart(const Http2FrameHeader& header) = 0; |
| |
| // Called after an entire CONTINUATION frame has been received. The frame is |
| // the end of the HEADERS if the END_HEADERS flag is set. |
| virtual void OnContinuationEnd() = 0; |
| |
| // Called when Pad Length field has been read. Applies to DATA and HEADERS |
| // frames. For PUSH_PROMISE frames, the Pad Length + 1 is provided in the |
| // OnPushPromiseStart call as total_padding_length. |
| virtual void OnPadLength(size_t pad_length) = 0; |
| |
| // Called when padding is skipped over. |
| virtual void OnPadding(const char* padding, size_t skipped_length) = 0; |
| |
| // Called when an entire RST_STREAM frame has been decoded. |
| // This is the only callback for RST_STREAM frames. |
| virtual void OnRstStream(const Http2FrameHeader& header, |
| Http2ErrorCode error_code) = 0; |
| |
| // Called once the common frame header has been decoded for a SETTINGS frame |
| // without the ACK flag, before examining the frame's payload, after which: |
| // OnSetting will be called in turn for each pair of settings parameter and |
| // value found in the payload; |
| // OnSettingsEnd will be called last; If the frame has no payload, |
| // then this will be called immediately after OnSettingsStart. |
| // The frame header is passed so that the caller can check the stream_id, |
| // which should be zero, but that hasn't been checked by the decoder. |
| virtual void OnSettingsStart(const Http2FrameHeader& header) = 0; |
| |
| // Called for each setting parameter and value within a SETTINGS frame. |
| virtual void OnSetting(const Http2SettingFields& setting_fields) = 0; |
| |
| // Called after parsing the complete payload of SETTINGS frame (non-ACK). |
| virtual void OnSettingsEnd() = 0; |
| |
| // Called when an entire SETTINGS frame, with the ACK flag, has been decoded. |
| virtual void OnSettingsAck(const Http2FrameHeader& header) = 0; |
| |
| // Called just before starting to process the HPACK block of a PUSH_PROMISE |
| // frame. The Pad Length field has already been decoded at this point, so |
| // OnPadLength will not be called; note that total_padding_length is Pad |
| // Length + 1. After OnPushPromiseStart: |
| // OnHpackFragment as the remainder of the non-padding payload is available |
| // until all if has been provided; |
| // OnPadding will be called if the frame is padded AND the Pad Length field |
| // is greater than zero (i.e. total_padding_length > 1); |
| // OnPushPromiseEnd will be called last; If the frame is unpadded and has no |
| // payload, then this will be called immediately after OnPushPromiseStart. |
| virtual void OnPushPromiseStart(const Http2FrameHeader& header, |
| const Http2PushPromiseFields& promise, |
| size_t total_padding_length) = 0; |
| |
| // Called after all of the HPACK block fragment and padding of a PUSH_PROMISE |
| // has been decoded and delivered to the listener. This call indicates the end |
| // of the HPACK block if and only if the frame header had the END_HEADERS flag |
| // set (i.e. header.IsEndHeaders() is true); otherwise the next block must be |
| // a CONTINUATION frame with the same stream id (not the same promised stream |
| // id). |
| virtual void OnPushPromiseEnd() = 0; |
| |
| // Called when an entire PING frame, without the ACK flag, has been decoded. |
| virtual void OnPing(const Http2FrameHeader& header, |
| const Http2PingFields& ping) = 0; |
| |
| // Called when an entire PING frame, with the ACK flag, has been decoded. |
| virtual void OnPingAck(const Http2FrameHeader& header, |
| const Http2PingFields& ping) = 0; |
| |
| // Called after parsing a GOAWAY frame's header and fixed size fields, after |
| // which: |
| // OnGoAwayOpaqueData will be called as opaque data of the payload becomes |
| // available to the decoder, until all of it has been provided to the |
| // listener; |
| // OnGoAwayEnd will be called last, after all the opaque data has been |
| // provided to the listener; if there is no opaque data, then OnGoAwayEnd |
| // will be called immediately after OnGoAwayStart. |
| virtual void OnGoAwayStart(const Http2FrameHeader& header, |
| const Http2GoAwayFields& goaway) = 0; |
| |
| // Called when the next portion of a GOAWAY frame's payload is received. |
| // |data| The start of |len| bytes of opaque data. |
| // |len| The length of the opaque data buffer. Maybe zero in some cases, |
| // which does not mean anything special. |
| virtual void OnGoAwayOpaqueData(const char* data, size_t len) = 0; |
| |
| // Called after finishing decoding all of a GOAWAY frame. |
| virtual void OnGoAwayEnd() = 0; |
| |
| // Called when an entire WINDOW_UPDATE frame has been decoded. The |
| // window_size_increment is required to be non-zero, but that has not been |
| // checked. If header.stream_id==0, the connection's flow control window is |
| // being increased, else the specified stream's flow control is being |
| // increased. |
| virtual void OnWindowUpdate(const Http2FrameHeader& header, |
| uint32_t window_size_increment) = 0; |
| |
| // Called when an ALTSVC frame header and origin length have been parsed. |
| // Either or both lengths may be zero. After OnAltSvcStart: |
| // OnAltSvcOriginData will be called until all of the (optional) Origin |
| // has been provided; |
| // OnAltSvcValueData will be called until all of the Alt-Svc-Field-Value |
| // has been provided; |
| // OnAltSvcEnd will called last, after all of the origin and |
| // Alt-Svc-Field-Value have been delivered to the listener. |
| virtual void OnAltSvcStart(const Http2FrameHeader& header, |
| size_t origin_length, |
| size_t value_length) = 0; |
| |
| // Called when decoding the (optional) origin of an ALTSVC; |
| // the field is uninterpreted. |
| virtual void OnAltSvcOriginData(const char* data, size_t len) = 0; |
| |
| // Called when decoding the Alt-Svc-Field-Value of an ALTSVC; |
| // the field is uninterpreted. |
| virtual void OnAltSvcValueData(const char* data, size_t len) = 0; |
| |
| // Called after decoding all of a ALTSVC frame and providing to the listener |
| // via the above methods. |
| virtual void OnAltSvcEnd() = 0; |
| |
| // Called when the common frame header has been decoded, but the frame type |
| // is unknown, after which: |
| // OnUnknownPayload is called as the payload of the frame is provided to the |
| // decoder, until all of the payload has been decoded; |
| // OnUnknownEnd will called last, after the entire frame of the unknown type |
| // has been decoded and provided to the listener. |
| virtual void OnUnknownStart(const Http2FrameHeader& header) = 0; |
| |
| // Called when the payload of an unknown frame type is received. |
| // |data| A buffer containing the data received. |
| // |len| The length of the data buffer. |
| virtual void OnUnknownPayload(const char* data, size_t len) = 0; |
| |
| // Called after decoding all of the payload of an unknown frame type. |
| virtual void OnUnknownEnd() = 0; |
| |
| ////////////////////////////////////////////////////////////////////////////// |
| // Below here are events indicating a problem has been detected during |
| // decoding (i.e. the received frames are malformed in some way). |
| |
| // Padding field (uint8) has a value that is too large (i.e. the amount of |
| // padding is greater than the remainder of the payload that isn't required). |
| // From RFC Section 6.1, DATA: |
| // If the length of the padding is the length of the frame payload or |
| // greater, the recipient MUST treat this as a connection error |
| // (Section 5.4.1) of type PROTOCOL_ERROR. |
| // The same is true for HEADERS and PUSH_PROMISE. |
| virtual void OnPaddingTooLong(const Http2FrameHeader& header, |
| size_t missing_length) = 0; |
| |
| // Frame size error. Depending upon the effected frame, this may or may not |
| // require terminating the connection, though that is probably the best thing |
| // to do. |
| // From RFC Section 4.2, Frame Size: |
| // An endpoint MUST send an error code of FRAME_SIZE_ERROR if a frame |
| // exceeds the size defined in SETTINGS_MAX_FRAME_SIZE, exceeds any limit |
| // defined for the frame type, or is too small to contain mandatory frame |
| // data. A frame size error in a frame that could alter the state of the |
| // the entire connection MUST be treated as a connection error |
| // (Section 5.4.1); this includes any frame carrying a header block |
| // (Section 4.3) (that is, HEADERS, PUSH_PROMISE, and CONTINUATION), |
| // SETTINGS, and any frame with a stream identifier of 0. |
| virtual void OnFrameSizeError(const Http2FrameHeader& header) = 0; |
| }; |
| |
| // Do nothing for each call. Useful for ignoring a frame that is invalid. |
| class Http2FrameDecoderNoOpListener : public Http2FrameDecoderListener { |
| public: |
| Http2FrameDecoderNoOpListener() {} |
| ~Http2FrameDecoderNoOpListener() override {} |
| |
| // TODO(jamessynge): Remove OnFrameHeader once done with supporting |
| // SpdyFramer's exact states. |
| bool OnFrameHeader(const Http2FrameHeader& header) override; |
| |
| void OnDataStart(const Http2FrameHeader& header) override {} |
| void OnDataPayload(const char* data, size_t len) override {} |
| void OnDataEnd() override {} |
| void OnHeadersStart(const Http2FrameHeader& header) override {} |
| void OnHeadersPriority(const Http2PriorityFields& priority) override {} |
| void OnHpackFragment(const char* data, size_t len) override {} |
| void OnHeadersEnd() override {} |
| void OnPriorityFrame(const Http2FrameHeader& header, |
| const Http2PriorityFields& priority) override {} |
| void OnContinuationStart(const Http2FrameHeader& header) override {} |
| void OnContinuationEnd() override {} |
| void OnPadLength(size_t trailing_length) override {} |
| void OnPadding(const char* padding, size_t skipped_length) override {} |
| void OnRstStream(const Http2FrameHeader& header, |
| Http2ErrorCode error_code) override {} |
| void OnSettingsStart(const Http2FrameHeader& header) override {} |
| void OnSetting(const Http2SettingFields& setting_fields) override {} |
| void OnSettingsEnd() override {} |
| void OnSettingsAck(const Http2FrameHeader& header) override {} |
| void OnPushPromiseStart(const Http2FrameHeader& header, |
| const Http2PushPromiseFields& promise, |
| size_t total_padding_length) override {} |
| void OnPushPromiseEnd() override {} |
| void OnPing(const Http2FrameHeader& header, |
| const Http2PingFields& ping) override {} |
| void OnPingAck(const Http2FrameHeader& header, |
| const Http2PingFields& ping) override {} |
| void OnGoAwayStart(const Http2FrameHeader& header, |
| const Http2GoAwayFields& goaway) override {} |
| void OnGoAwayOpaqueData(const char* data, size_t len) override {} |
| void OnGoAwayEnd() override {} |
| void OnWindowUpdate(const Http2FrameHeader& header, |
| uint32_t increment) override {} |
| void OnAltSvcStart(const Http2FrameHeader& header, |
| size_t origin_length, |
| size_t value_length) override {} |
| void OnAltSvcOriginData(const char* data, size_t len) override {} |
| void OnAltSvcValueData(const char* data, size_t len) override {} |
| void OnAltSvcEnd() override {} |
| void OnUnknownStart(const Http2FrameHeader& header) override {} |
| void OnUnknownPayload(const char* data, size_t len) override {} |
| void OnUnknownEnd() override {} |
| void OnPaddingTooLong(const Http2FrameHeader& header, |
| size_t missing_length) override {} |
| void OnFrameSizeError(const Http2FrameHeader& header) override {} |
| }; |
| |
| static_assert(!std::is_abstract<Http2FrameDecoderNoOpListener>(), |
| "Http2FrameDecoderNoOpListener ought to be concrete."); |
| |
| } // namespace http2 |
| |
| #endif // QUICHE_HTTP2_DECODER_HTTP2_FRAME_DECODER_LISTENER_H_ |