blob: 13837877e4bae36b58b918eef8a7cff00d17aa5e [file] [log] [blame]
// 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