blob: 51ed305f3e7c9419743d9decb456751b44372810 [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 "http2/decoder/payload_decoders/goaway_payload_decoder.h"
#include <stddef.h>
#include "http2/decoder/decode_buffer.h"
#include "http2/decoder/http2_frame_decoder_listener.h"
#include "http2/http2_constants.h"
#include "http2/http2_structures.h"
#include "http2/platform/api/http2_bug_tracker.h"
#include "http2/platform/api/http2_logging.h"
#include "http2/platform/api/http2_macros.h"
namespace http2 {
std::ostream& operator<<(std::ostream& out,
GoAwayPayloadDecoder::PayloadState v) {
switch (v) {
case GoAwayPayloadDecoder::PayloadState::kStartDecodingFixedFields:
return out << "kStartDecodingFixedFields";
case GoAwayPayloadDecoder::PayloadState::kHandleFixedFieldsStatus:
return out << "kHandleFixedFieldsStatus";
case GoAwayPayloadDecoder::PayloadState::kReadOpaqueData:
return out << "kReadOpaqueData";
case GoAwayPayloadDecoder::PayloadState::kResumeDecodingFixedFields:
return out << "kResumeDecodingFixedFields";
}
// 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);
HTTP2_BUG << "Invalid GoAwayPayloadDecoder::PayloadState: " << unknown;
return out << "GoAwayPayloadDecoder::PayloadState(" << unknown << ")";
}
DecodeStatus GoAwayPayloadDecoder::StartDecodingPayload(
FrameDecoderState* state,
DecodeBuffer* db) {
HTTP2_DVLOG(2) << "GoAwayPayloadDecoder::StartDecodingPayload: "
<< state->frame_header();
DCHECK_EQ(Http2FrameType::GOAWAY, state->frame_header().type);
DCHECK_LE(db->Remaining(), state->frame_header().payload_length);
DCHECK_EQ(0, state->frame_header().flags);
state->InitializeRemainders();
payload_state_ = PayloadState::kStartDecodingFixedFields;
return ResumeDecodingPayload(state, db);
}
DecodeStatus GoAwayPayloadDecoder::ResumeDecodingPayload(
FrameDecoderState* state,
DecodeBuffer* db) {
HTTP2_DVLOG(2)
<< "GoAwayPayloadDecoder::ResumeDecodingPayload: remaining_payload="
<< state->remaining_payload() << ", db->Remaining=" << db->Remaining();
const Http2FrameHeader& frame_header = state->frame_header();
DCHECK_EQ(Http2FrameType::GOAWAY, frame_header.type);
DCHECK_LE(db->Remaining(), frame_header.payload_length);
DCHECK_NE(PayloadState::kHandleFixedFieldsStatus, payload_state_);
// |status| has to be initialized to some value to avoid compiler error in
// case PayloadState::kHandleFixedFieldsStatus below, but value does not
// matter, see DCHECK_NE above.
DecodeStatus status = DecodeStatus::kDecodeError;
size_t avail;
while (true) {
HTTP2_DVLOG(2)
<< "GoAwayPayloadDecoder::ResumeDecodingPayload payload_state_="
<< payload_state_;
switch (payload_state_) {
case PayloadState::kStartDecodingFixedFields:
status = state->StartDecodingStructureInPayload(&goaway_fields_, db);
HTTP2_FALLTHROUGH;
case PayloadState::kHandleFixedFieldsStatus:
if (status == DecodeStatus::kDecodeDone) {
state->listener()->OnGoAwayStart(frame_header, goaway_fields_);
} else {
// Not done decoding the structure. Either we've got more payload
// to decode, or we've run out because the payload is too short,
// in which case OnFrameSizeError will have already been called.
DCHECK((status == DecodeStatus::kDecodeInProgress &&
state->remaining_payload() > 0) ||
(status == DecodeStatus::kDecodeError &&
state->remaining_payload() == 0))
<< "\n status=" << status
<< "; remaining_payload=" << state->remaining_payload();
payload_state_ = PayloadState::kResumeDecodingFixedFields;
return status;
}
HTTP2_FALLTHROUGH;
case PayloadState::kReadOpaqueData:
// The opaque data is all the remains to be decoded, so anything left
// in the decode buffer is opaque data.
avail = db->Remaining();
if (avail > 0) {
state->listener()->OnGoAwayOpaqueData(db->cursor(), avail);
db->AdvanceCursor(avail);
state->ConsumePayload(avail);
}
if (state->remaining_payload() > 0) {
payload_state_ = PayloadState::kReadOpaqueData;
return DecodeStatus::kDecodeInProgress;
}
state->listener()->OnGoAwayEnd();
return DecodeStatus::kDecodeDone;
case PayloadState::kResumeDecodingFixedFields:
status = state->ResumeDecodingStructureInPayload(&goaway_fields_, db);
payload_state_ = PayloadState::kHandleFixedFieldsStatus;
continue;
}
HTTP2_BUG << "PayloadState: " << payload_state_;
}
}
} // namespace http2