naiveproxy/net/http2/decoder/frame_decoder_state.cc
2018-02-02 05:49:39 -05:00

82 lines
3.0 KiB
C++

// 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 "net/http2/decoder/frame_decoder_state.h"
namespace net {
DecodeStatus FrameDecoderState::ReadPadLength(DecodeBuffer* db,
bool report_pad_length) {
DVLOG(2) << "ReadPadLength db->Remaining=" << db->Remaining()
<< "; payload_length=" << frame_header().payload_length;
DCHECK(IsPaddable());
DCHECK(frame_header().IsPadded());
// Pad Length is always at the start of the frame, so remaining_payload_
// should equal payload_length at this point.
const uint32_t total_payload = frame_header().payload_length;
DCHECK_EQ(total_payload, remaining_payload_);
DCHECK_EQ(0u, remaining_padding_);
if (db->HasData()) {
const uint32_t pad_length = db->DecodeUInt8();
const uint32_t total_padding = pad_length + 1;
if (total_padding <= total_payload) {
remaining_padding_ = pad_length;
remaining_payload_ = total_payload - total_padding;
if (report_pad_length) {
listener()->OnPadLength(pad_length);
}
return DecodeStatus::kDecodeDone;
}
const uint32_t missing_length = total_padding - total_payload;
// To allow for the possibility of recovery, record the number of
// remaining bytes of the frame's payload (invalid though it is)
// in remaining_payload_.
remaining_payload_ = total_payload - 1; // 1 for sizeof(Pad Length).
remaining_padding_ = 0;
listener()->OnPaddingTooLong(frame_header(), missing_length);
return DecodeStatus::kDecodeError;
}
if (total_payload == 0) {
remaining_payload_ = 0;
remaining_padding_ = 0;
listener()->OnPaddingTooLong(frame_header(), 1);
return DecodeStatus::kDecodeError;
}
// Need to wait for another buffer.
return DecodeStatus::kDecodeInProgress;
}
bool FrameDecoderState::SkipPadding(DecodeBuffer* db) {
DVLOG(2) << "SkipPadding remaining_padding_=" << remaining_padding_
<< ", db->Remaining=" << db->Remaining()
<< ", header: " << frame_header();
DCHECK_EQ(remaining_payload_, 0u);
DCHECK(IsPaddable()) << "header: " << frame_header();
DCHECK_GE(remaining_padding_, 0u);
DCHECK(remaining_padding_ == 0 || frame_header().IsPadded())
<< "remaining_padding_=" << remaining_padding_
<< ", header: " << frame_header();
const size_t avail = AvailablePadding(db);
if (avail > 0) {
listener()->OnPadding(db->cursor(), avail);
db->AdvanceCursor(avail);
remaining_padding_ -= avail;
}
return remaining_padding_ == 0;
}
DecodeStatus FrameDecoderState::ReportFrameSizeError() {
DVLOG(2) << "FrameDecoderState::ReportFrameSizeError: "
<< " remaining_payload_=" << remaining_payload_
<< "; remaining_padding_=" << remaining_padding_
<< ", header: " << frame_header();
listener()->OnFrameSizeError(frame_header());
return DecodeStatus::kDecodeError;
}
} // namespace net