| // 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. |
| |
| #include "quiche/http2/decoder/payload_decoders/data_payload_decoder.h" |
| |
| #include <stddef.h> |
| |
| #include <ostream> |
| |
| #include "absl/base/macros.h" |
| #include "quiche/http2/decoder/decode_buffer.h" |
| #include "quiche/http2/decoder/http2_frame_decoder_listener.h" |
| #include "quiche/http2/http2_constants.h" |
| #include "quiche/http2/http2_structures.h" |
| #include "quiche/common/platform/api/quiche_bug_tracker.h" |
| #include "quiche/common/platform/api/quiche_logging.h" |
| |
| namespace http2 { |
| |
| std::ostream& operator<<(std::ostream& out, |
| DataPayloadDecoder::PayloadState v) { |
| switch (v) { |
| case DataPayloadDecoder::PayloadState::kReadPadLength: |
| return out << "kReadPadLength"; |
| case DataPayloadDecoder::PayloadState::kReadPayload: |
| return out << "kReadPayload"; |
| case DataPayloadDecoder::PayloadState::kSkipPadding: |
| return out << "kSkipPadding"; |
| } |
| // Since the value doesn't come over the wire, only a programming bug should |
| // result in reaching this point. |
| int unknown = static_cast<int>(v); |
| QUICHE_BUG(http2_bug_174_1) |
| << "Invalid DataPayloadDecoder::PayloadState: " << unknown; |
| return out << "DataPayloadDecoder::PayloadState(" << unknown << ")"; |
| } |
| |
| DecodeStatus DataPayloadDecoder::StartDecodingPayload(FrameDecoderState* state, |
| DecodeBuffer* db) { |
| const Http2FrameHeader& frame_header = state->frame_header(); |
| const uint32_t total_length = frame_header.payload_length; |
| |
| QUICHE_DVLOG(2) << "DataPayloadDecoder::StartDecodingPayload: " |
| << frame_header; |
| QUICHE_DCHECK_EQ(Http2FrameType::DATA, frame_header.type); |
| QUICHE_DCHECK_LE(db->Remaining(), total_length); |
| QUICHE_DCHECK_EQ(0, frame_header.flags & ~(Http2FrameFlag::END_STREAM | |
| Http2FrameFlag::PADDED)); |
| |
| // Special case for the hoped for common case: unpadded and fits fully into |
| // the decode buffer. TO BE SEEN if that is true. It certainly requires that |
| // the transport buffers be large (e.g. >> 16KB typically). |
| // TODO(jamessynge) Add counters. |
| QUICHE_DVLOG(2) << "StartDecodingPayload total_length=" << total_length; |
| if (!frame_header.IsPadded()) { |
| QUICHE_DVLOG(2) << "StartDecodingPayload !IsPadded"; |
| if (db->Remaining() == total_length) { |
| QUICHE_DVLOG(2) << "StartDecodingPayload all present"; |
| // Note that we don't cache the listener field so that the callee can |
| // replace it if the frame is bad. |
| // If this case is common enough, consider combining the 3 callbacks |
| // into one. |
| state->listener()->OnDataStart(frame_header); |
| if (total_length > 0) { |
| state->listener()->OnDataPayload(db->cursor(), total_length); |
| db->AdvanceCursor(total_length); |
| } |
| state->listener()->OnDataEnd(); |
| return DecodeStatus::kDecodeDone; |
| } |
| payload_state_ = PayloadState::kReadPayload; |
| } else { |
| payload_state_ = PayloadState::kReadPadLength; |
| } |
| state->InitializeRemainders(); |
| state->listener()->OnDataStart(frame_header); |
| return ResumeDecodingPayload(state, db); |
| } |
| |
| DecodeStatus DataPayloadDecoder::ResumeDecodingPayload(FrameDecoderState* state, |
| DecodeBuffer* db) { |
| QUICHE_DVLOG(2) << "DataPayloadDecoder::ResumeDecodingPayload payload_state_=" |
| << payload_state_; |
| const Http2FrameHeader& frame_header = state->frame_header(); |
| QUICHE_DCHECK_EQ(Http2FrameType::DATA, frame_header.type); |
| QUICHE_DCHECK_LE(state->remaining_payload_and_padding(), |
| frame_header.payload_length); |
| QUICHE_DCHECK_LE(db->Remaining(), state->remaining_payload_and_padding()); |
| DecodeStatus status; |
| size_t avail; |
| switch (payload_state_) { |
| case PayloadState::kReadPadLength: |
| // ReadPadLength handles the OnPadLength callback, and updating the |
| // remaining_payload and remaining_padding fields. If the amount of |
| // padding is too large to fit in the frame's payload, ReadPadLength |
| // instead calls OnPaddingTooLong and returns kDecodeError. |
| status = state->ReadPadLength(db, /*report_pad_length*/ true); |
| if (status != DecodeStatus::kDecodeDone) { |
| return status; |
| } |
| ABSL_FALLTHROUGH_INTENDED; |
| |
| case PayloadState::kReadPayload: |
| avail = state->AvailablePayload(db); |
| if (avail > 0) { |
| state->listener()->OnDataPayload(db->cursor(), avail); |
| db->AdvanceCursor(avail); |
| state->ConsumePayload(avail); |
| } |
| if (state->remaining_payload() > 0) { |
| payload_state_ = PayloadState::kReadPayload; |
| return DecodeStatus::kDecodeInProgress; |
| } |
| ABSL_FALLTHROUGH_INTENDED; |
| |
| case PayloadState::kSkipPadding: |
| // SkipPadding handles the OnPadding callback. |
| if (state->SkipPadding(db)) { |
| state->listener()->OnDataEnd(); |
| return DecodeStatus::kDecodeDone; |
| } |
| payload_state_ = PayloadState::kSkipPadding; |
| return DecodeStatus::kDecodeInProgress; |
| } |
| QUICHE_BUG(http2_bug_174_2) << "PayloadState: " << payload_state_; |
| return DecodeStatus::kDecodeError; |
| } |
| |
| } // namespace http2 |