1 // Copyright 2016 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "quiche/http2/decoder/payload_decoders/settings_payload_decoder.h"
6
7 #include "quiche/http2/decoder/decode_buffer.h"
8 #include "quiche/http2/decoder/http2_frame_decoder_listener.h"
9 #include "quiche/http2/http2_constants.h"
10 #include "quiche/http2/http2_structures.h"
11 #include "quiche/common/platform/api/quiche_logging.h"
12
13 namespace http2 {
14
StartDecodingPayload(FrameDecoderState * state,DecodeBuffer * db)15 DecodeStatus SettingsPayloadDecoder::StartDecodingPayload(
16 FrameDecoderState* state, DecodeBuffer* db) {
17 const Http2FrameHeader& frame_header = state->frame_header();
18 const uint32_t total_length = frame_header.payload_length;
19
20 QUICHE_DVLOG(2) << "SettingsPayloadDecoder::StartDecodingPayload: "
21 << frame_header;
22 QUICHE_DCHECK_EQ(Http2FrameType::SETTINGS, frame_header.type);
23 QUICHE_DCHECK_LE(db->Remaining(), total_length);
24 QUICHE_DCHECK_EQ(0, frame_header.flags & ~(Http2FrameFlag::ACK));
25
26 if (frame_header.IsAck()) {
27 if (total_length == 0) {
28 state->listener()->OnSettingsAck(frame_header);
29 return DecodeStatus::kDecodeDone;
30 } else {
31 state->InitializeRemainders();
32 return state->ReportFrameSizeError();
33 }
34 } else {
35 state->InitializeRemainders();
36 state->listener()->OnSettingsStart(frame_header);
37 return StartDecodingSettings(state, db);
38 }
39 }
40
ResumeDecodingPayload(FrameDecoderState * state,DecodeBuffer * db)41 DecodeStatus SettingsPayloadDecoder::ResumeDecodingPayload(
42 FrameDecoderState* state, DecodeBuffer* db) {
43 QUICHE_DVLOG(2) << "SettingsPayloadDecoder::ResumeDecodingPayload"
44 << " remaining_payload=" << state->remaining_payload()
45 << " db->Remaining=" << db->Remaining();
46 QUICHE_DCHECK_EQ(Http2FrameType::SETTINGS, state->frame_header().type);
47 QUICHE_DCHECK_LE(db->Remaining(), state->frame_header().payload_length);
48
49 DecodeStatus status =
50 state->ResumeDecodingStructureInPayload(&setting_fields_, db);
51 if (status == DecodeStatus::kDecodeDone) {
52 state->listener()->OnSetting(setting_fields_);
53 return StartDecodingSettings(state, db);
54 }
55 return HandleNotDone(state, db, status);
56 }
57
StartDecodingSettings(FrameDecoderState * state,DecodeBuffer * db)58 DecodeStatus SettingsPayloadDecoder::StartDecodingSettings(
59 FrameDecoderState* state, DecodeBuffer* db) {
60 QUICHE_DVLOG(2) << "SettingsPayloadDecoder::StartDecodingSettings"
61 << " remaining_payload=" << state->remaining_payload()
62 << " db->Remaining=" << db->Remaining();
63 while (state->remaining_payload() > 0) {
64 DecodeStatus status =
65 state->StartDecodingStructureInPayload(&setting_fields_, db);
66 if (status == DecodeStatus::kDecodeDone) {
67 state->listener()->OnSetting(setting_fields_);
68 continue;
69 }
70 return HandleNotDone(state, db, status);
71 }
72 QUICHE_DVLOG(2) << "LEAVING SettingsPayloadDecoder::StartDecodingSettings"
73 << "\n\tdb->Remaining=" << db->Remaining()
74 << "\n\t remaining_payload=" << state->remaining_payload();
75 state->listener()->OnSettingsEnd();
76 return DecodeStatus::kDecodeDone;
77 }
78
HandleNotDone(FrameDecoderState * state,DecodeBuffer * db,DecodeStatus status)79 DecodeStatus SettingsPayloadDecoder::HandleNotDone(FrameDecoderState* state,
80 DecodeBuffer* db,
81 DecodeStatus status) {
82 // Not done decoding the structure. Either we've got more payload to decode,
83 // or we've run out because the payload is too short, in which case
84 // OnFrameSizeError will have already been called.
85 QUICHE_DCHECK(
86 (status == DecodeStatus::kDecodeInProgress &&
87 state->remaining_payload() > 0) ||
88 (status == DecodeStatus::kDecodeError && state->remaining_payload() == 0))
89 << "\n status=" << status
90 << "; remaining_payload=" << state->remaining_payload()
91 << "; db->Remaining=" << db->Remaining();
92 return status;
93 }
94
95 } // namespace http2
96