1 /*
2 * Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 #include "modules/rtp_rtcp/source/rtcp_packet/extended_reports.h"
12
13 #include "modules/rtp_rtcp/source/byte_io.h"
14 #include "modules/rtp_rtcp/source/rtcp_packet/common_header.h"
15 #include "rtc_base/checks.h"
16 #include "rtc_base/logging.h"
17
18 namespace webrtc {
19 namespace rtcp {
20 constexpr uint8_t ExtendedReports::kPacketType;
21 // From RFC 3611: RTP Control Protocol Extended Reports (RTCP XR).
22 //
23 // Format for XR packets:
24 //
25 // 0 1 2 3
26 // 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
27 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
28 // |V=2|P|reserved | PT=XR=207 | length |
29 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
30 // | SSRC |
31 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
32 // : report blocks :
33 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
34 //
35 // Extended report block:
36 // 0 1 2 3
37 // 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
38 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
39 // | Block Type | reserved | block length |
40 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41 // : type-specific block contents :
42 // +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
ExtendedReports()43 ExtendedReports::ExtendedReports() : sender_ssrc_(0) {}
~ExtendedReports()44 ExtendedReports::~ExtendedReports() {}
45
Parse(const CommonHeader & packet)46 bool ExtendedReports::Parse(const CommonHeader& packet) {
47 RTC_DCHECK_EQ(packet.type(), kPacketType);
48
49 if (packet.payload_size_bytes() < kXrBaseLength) {
50 RTC_LOG(LS_WARNING)
51 << "Packet is too small to be an ExtendedReports packet.";
52 return false;
53 }
54
55 sender_ssrc_ = ByteReader<uint32_t>::ReadBigEndian(packet.payload());
56 rrtr_block_.reset();
57 dlrr_block_.ClearItems();
58 voip_metric_block_.reset();
59 target_bitrate_ = rtc::nullopt;
60
61 const uint8_t* current_block = packet.payload() + kXrBaseLength;
62 const uint8_t* const packet_end =
63 packet.payload() + packet.payload_size_bytes();
64 constexpr size_t kBlockHeaderSizeBytes = 4;
65 while (current_block + kBlockHeaderSizeBytes <= packet_end) {
66 uint8_t block_type = ByteReader<uint8_t>::ReadBigEndian(current_block);
67 uint16_t block_length =
68 ByteReader<uint16_t>::ReadBigEndian(current_block + 2);
69 const uint8_t* next_block =
70 current_block + kBlockHeaderSizeBytes + block_length * 4;
71 if (next_block > packet_end) {
72 RTC_LOG(LS_WARNING)
73 << "Report block in extended report packet is too big.";
74 return false;
75 }
76 switch (block_type) {
77 case Rrtr::kBlockType:
78 ParseRrtrBlock(current_block, block_length);
79 break;
80 case Dlrr::kBlockType:
81 ParseDlrrBlock(current_block, block_length);
82 break;
83 case VoipMetric::kBlockType:
84 ParseVoipMetricBlock(current_block, block_length);
85 break;
86 case TargetBitrate::kBlockType:
87 ParseTargetBitrateBlock(current_block, block_length);
88 break;
89 default:
90 // Unknown block, ignore.
91 RTC_LOG(LS_WARNING)
92 << "Unknown extended report block type " << block_type;
93 break;
94 }
95 current_block = next_block;
96 }
97
98 return true;
99 }
100
SetRrtr(const Rrtr & rrtr)101 void ExtendedReports::SetRrtr(const Rrtr& rrtr) {
102 if (rrtr_block_)
103 RTC_LOG(LS_WARNING) << "Rrtr already set, overwriting.";
104 rrtr_block_.emplace(rrtr);
105 }
106
AddDlrrItem(const ReceiveTimeInfo & time_info)107 void ExtendedReports::AddDlrrItem(const ReceiveTimeInfo& time_info) {
108 dlrr_block_.AddDlrrItem(time_info);
109 }
110
SetVoipMetric(const VoipMetric & voip_metric)111 void ExtendedReports::SetVoipMetric(const VoipMetric& voip_metric) {
112 if (voip_metric_block_)
113 RTC_LOG(LS_WARNING) << "Voip metric already set, overwriting.";
114 voip_metric_block_.emplace(voip_metric);
115 }
116
SetTargetBitrate(const TargetBitrate & bitrate)117 void ExtendedReports::SetTargetBitrate(const TargetBitrate& bitrate) {
118 if (target_bitrate_)
119 RTC_LOG(LS_WARNING) << "TargetBitrate already set, overwriting.";
120
121 target_bitrate_ = bitrate;
122 }
123
BlockLength() const124 size_t ExtendedReports::BlockLength() const {
125 return kHeaderLength + kXrBaseLength + RrtrLength() + DlrrLength() +
126 VoipMetricLength() + TargetBitrateLength();
127 }
128
Create(uint8_t * packet,size_t * index,size_t max_length,RtcpPacket::PacketReadyCallback * callback) const129 bool ExtendedReports::Create(uint8_t* packet,
130 size_t* index,
131 size_t max_length,
132 RtcpPacket::PacketReadyCallback* callback) const {
133 while (*index + BlockLength() > max_length) {
134 if (!OnBufferFull(packet, index, callback))
135 return false;
136 }
137 size_t index_end = *index + BlockLength();
138 const uint8_t kReserved = 0;
139 CreateHeader(kReserved, kPacketType, HeaderLength(), packet, index);
140 ByteWriter<uint32_t>::WriteBigEndian(packet + *index, sender_ssrc_);
141 *index += sizeof(uint32_t);
142 if (rrtr_block_) {
143 rrtr_block_->Create(packet + *index);
144 *index += Rrtr::kLength;
145 }
146 if (dlrr_block_) {
147 dlrr_block_.Create(packet + *index);
148 *index += dlrr_block_.BlockLength();
149 }
150 if (voip_metric_block_) {
151 voip_metric_block_->Create(packet + *index);
152 *index += VoipMetric::kLength;
153 }
154 if (target_bitrate_) {
155 target_bitrate_->Create(packet + *index);
156 *index += target_bitrate_->BlockLength();
157 }
158 RTC_CHECK_EQ(*index, index_end);
159 return true;
160 }
161
TargetBitrateLength() const162 size_t ExtendedReports::TargetBitrateLength() const {
163 if (target_bitrate_)
164 return target_bitrate_->BlockLength();
165 return 0;
166 }
167
ParseRrtrBlock(const uint8_t * block,uint16_t block_length)168 void ExtendedReports::ParseRrtrBlock(const uint8_t* block,
169 uint16_t block_length) {
170 if (block_length != Rrtr::kBlockLength) {
171 RTC_LOG(LS_WARNING) << "Incorrect rrtr block size " << block_length
172 << " Should be " << Rrtr::kBlockLength;
173 return;
174 }
175 if (rrtr_block_) {
176 RTC_LOG(LS_WARNING)
177 << "Two rrtr blocks found in same Extended Report packet";
178 return;
179 }
180 rrtr_block_.emplace();
181 rrtr_block_->Parse(block);
182 }
183
ParseDlrrBlock(const uint8_t * block,uint16_t block_length)184 void ExtendedReports::ParseDlrrBlock(const uint8_t* block,
185 uint16_t block_length) {
186 if (dlrr_block_) {
187 RTC_LOG(LS_WARNING)
188 << "Two Dlrr blocks found in same Extended Report packet";
189 return;
190 }
191 dlrr_block_.Parse(block, block_length);
192 }
193
ParseVoipMetricBlock(const uint8_t * block,uint16_t block_length)194 void ExtendedReports::ParseVoipMetricBlock(const uint8_t* block,
195 uint16_t block_length) {
196 if (block_length != VoipMetric::kBlockLength) {
197 RTC_LOG(LS_WARNING) << "Incorrect voip metric block size " << block_length
198 << " Should be " << VoipMetric::kBlockLength;
199 return;
200 }
201 if (voip_metric_block_) {
202 RTC_LOG(LS_WARNING)
203 << "Two Voip Metric blocks found in same Extended Report packet";
204 return;
205 }
206 voip_metric_block_.emplace();
207 voip_metric_block_->Parse(block);
208 }
209
ParseTargetBitrateBlock(const uint8_t * block,uint16_t block_length)210 void ExtendedReports::ParseTargetBitrateBlock(const uint8_t* block,
211 uint16_t block_length) {
212 target_bitrate_.emplace();
213 target_bitrate_->Parse(block, block_length);
214 }
215 } // namespace rtcp
216 } // namespace webrtc
217