| /* |
| * Copyright (c) 2016 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #include "modules/rtp_rtcp/source/ulpfec_header_reader_writer.h" |
| |
| #include <string.h> |
| |
| #include <memory> |
| #include <utility> |
| |
| #include "api/scoped_refptr.h" |
| #include "modules/rtp_rtcp/source/byte_io.h" |
| #include "modules/rtp_rtcp/source/forward_error_correction.h" |
| #include "modules/rtp_rtcp/source/forward_error_correction_internal.h" |
| #include "rtc_base/checks.h" |
| #include "rtc_base/random.h" |
| #include "test/gmock.h" |
| #include "test/gtest.h" |
| |
| namespace webrtc { |
| |
| namespace { |
| |
| using Packet = ForwardErrorCorrection::Packet; |
| using ReceivedFecPacket = ForwardErrorCorrection::ReceivedFecPacket; |
| using ::testing::SizeIs; |
| |
| constexpr uint32_t kMediaSsrc = 1254983; |
| constexpr uint16_t kMediaStartSeqNum = 825; |
| constexpr size_t kMediaPacketLength = 1234; |
| |
| constexpr size_t kUlpfecHeaderSizeLBitClear = 14; |
| constexpr size_t kUlpfecHeaderSizeLBitSet = 18; |
| constexpr size_t kUlpfecPacketMaskOffset = 12; |
| |
| std::unique_ptr<uint8_t[]> GeneratePacketMask(size_t packet_mask_size, |
| uint64_t seed) { |
| Random random(seed); |
| std::unique_ptr<uint8_t[]> packet_mask(new uint8_t[packet_mask_size]); |
| for (size_t i = 0; i < packet_mask_size; ++i) { |
| packet_mask[i] = random.Rand<uint8_t>(); |
| } |
| return packet_mask; |
| } |
| |
| std::unique_ptr<Packet> WriteHeader(const uint8_t* packet_mask, |
| size_t packet_mask_size) { |
| UlpfecHeaderWriter writer; |
| std::unique_ptr<Packet> written_packet(new Packet()); |
| written_packet->data.SetSize(kMediaPacketLength); |
| uint8_t* data = written_packet->data.MutableData(); |
| for (size_t i = 0; i < written_packet->data.size(); ++i) { |
| data[i] = i; // Actual content doesn't matter. |
| } |
| const FecHeaderWriter::ProtectedStream protected_streams[] = { |
| {.ssrc = kMediaSsrc, |
| .seq_num_base = kMediaStartSeqNum, |
| .packet_mask = {packet_mask, packet_mask_size}}}; |
| writer.FinalizeFecHeader(protected_streams, *written_packet); |
| return written_packet; |
| } |
| |
| std::unique_ptr<ReceivedFecPacket> ReadHeader(const Packet& written_packet) { |
| UlpfecHeaderReader reader; |
| std::unique_ptr<ReceivedFecPacket> read_packet(new ReceivedFecPacket()); |
| read_packet->ssrc = kMediaSsrc; |
| read_packet->pkt = rtc::scoped_refptr<Packet>(new Packet()); |
| read_packet->pkt->data = written_packet.data; |
| EXPECT_TRUE(reader.ReadFecHeader(read_packet.get())); |
| return read_packet; |
| } |
| |
| void VerifyHeaders(size_t expected_fec_header_size, |
| const uint8_t* expected_packet_mask, |
| size_t expected_packet_mask_size, |
| const Packet& written_packet, |
| const ReceivedFecPacket& read_packet) { |
| EXPECT_EQ(kMediaSsrc, read_packet.ssrc); |
| EXPECT_EQ(expected_fec_header_size, read_packet.fec_header_size); |
| ASSERT_THAT(read_packet.protected_streams, SizeIs(1)); |
| EXPECT_EQ(read_packet.protected_streams[0].ssrc, kMediaSsrc); |
| EXPECT_EQ(read_packet.protected_streams[0].seq_num_base, kMediaStartSeqNum); |
| EXPECT_EQ(read_packet.protected_streams[0].packet_mask_offset, |
| kUlpfecPacketMaskOffset); |
| ASSERT_EQ(read_packet.protected_streams[0].packet_mask_size, |
| expected_packet_mask_size); |
| EXPECT_EQ(written_packet.data.size() - expected_fec_header_size, |
| read_packet.protection_length); |
| EXPECT_EQ(0, memcmp(expected_packet_mask, |
| read_packet.pkt->data.MutableData() + |
| read_packet.protected_streams[0].packet_mask_offset, |
| read_packet.protected_streams[0].packet_mask_size)); |
| // Verify that the call to ReadFecHeader did not tamper with the payload. |
| EXPECT_EQ(0, memcmp(written_packet.data.data() + expected_fec_header_size, |
| read_packet.pkt->data.cdata() + expected_fec_header_size, |
| written_packet.data.size() - expected_fec_header_size)); |
| } |
| |
| } // namespace |
| |
| TEST(UlpfecHeaderReaderTest, ReadsSmallHeader) { |
| const uint8_t packet[] = { |
| 0x00, 0x12, 0xab, 0xcd, // L bit clear, "random" payload type and SN base |
| 0x12, 0x34, 0x56, 0x78, // "random" TS recovery |
| 0xab, 0xcd, 0x11, 0x22, // "random" length recovery and protection length |
| 0x33, 0x44, // "random" packet mask |
| 0x00, 0x00, 0x00, 0x00 // payload |
| }; |
| const size_t packet_length = sizeof(packet); |
| ReceivedFecPacket read_packet; |
| read_packet.pkt = rtc::scoped_refptr<Packet>(new Packet()); |
| read_packet.pkt->data.SetData(packet, packet_length); |
| |
| UlpfecHeaderReader reader; |
| EXPECT_TRUE(reader.ReadFecHeader(&read_packet)); |
| |
| EXPECT_EQ(14U, read_packet.fec_header_size); |
| EXPECT_EQ(0xabcdU, read_packet.protected_streams[0].seq_num_base); |
| EXPECT_EQ(12U, read_packet.protected_streams[0].packet_mask_offset); |
| EXPECT_EQ(2U, read_packet.protected_streams[0].packet_mask_size); |
| EXPECT_EQ(0x1122U, read_packet.protection_length); |
| } |
| |
| TEST(UlpfecHeaderReaderTest, ReadsLargeHeader) { |
| const uint8_t packet[] = { |
| 0x40, 0x12, 0xab, 0xcd, // L bit set, "random" payload type and SN base |
| 0x12, 0x34, 0x56, 0x78, // "random" TS recovery |
| 0xab, 0xcd, 0x11, 0x22, // "random" length recovery and protection length |
| 0x33, 0x44, 0x55, 0x66, // "random" packet mask |
| 0x77, 0x88, // |
| 0x00, 0x00, 0x00, 0x00 // payload |
| }; |
| const size_t packet_length = sizeof(packet); |
| ReceivedFecPacket read_packet; |
| read_packet.pkt = rtc::scoped_refptr<Packet>(new Packet()); |
| read_packet.pkt->data.SetData(packet, packet_length); |
| |
| UlpfecHeaderReader reader; |
| EXPECT_TRUE(reader.ReadFecHeader(&read_packet)); |
| |
| EXPECT_EQ(18U, read_packet.fec_header_size); |
| EXPECT_EQ(0xabcdU, read_packet.protected_streams[0].seq_num_base); |
| EXPECT_EQ(12U, read_packet.protected_streams[0].packet_mask_offset); |
| EXPECT_EQ(6U, read_packet.protected_streams[0].packet_mask_size); |
| EXPECT_EQ(0x1122U, read_packet.protection_length); |
| } |
| |
| TEST(UlpfecHeaderWriterTest, FinalizesSmallHeader) { |
| const size_t packet_mask_size = kUlpfecPacketMaskSizeLBitClear; |
| auto packet_mask = GeneratePacketMask(packet_mask_size, 0xabcd); |
| Packet written_packet; |
| written_packet.data.SetSize(kMediaPacketLength); |
| uint8_t* data = written_packet.data.MutableData(); |
| for (size_t i = 0; i < written_packet.data.size(); ++i) { |
| data[i] = i; |
| } |
| |
| UlpfecHeaderWriter writer; |
| const FecHeaderWriter::ProtectedStream protected_streams[] = { |
| {.ssrc = kMediaSsrc, |
| .seq_num_base = kMediaStartSeqNum, |
| .packet_mask = {packet_mask.get(), packet_mask_size}}}; |
| writer.FinalizeFecHeader(protected_streams, written_packet); |
| |
| const uint8_t* packet = written_packet.data.cdata(); |
| EXPECT_EQ(0x00, packet[0] & 0x80); // E bit. |
| EXPECT_EQ(0x00, packet[0] & 0x40); // L bit. |
| EXPECT_EQ(kMediaStartSeqNum, ByteReader<uint16_t>::ReadBigEndian(packet + 2)); |
| EXPECT_EQ( |
| static_cast<uint16_t>(kMediaPacketLength - kUlpfecHeaderSizeLBitClear), |
| ByteReader<uint16_t>::ReadBigEndian(packet + 10)); |
| EXPECT_EQ(0, memcmp(packet + kUlpfecPacketMaskOffset, packet_mask.get(), |
| packet_mask_size)); |
| } |
| |
| TEST(UlpfecHeaderWriterTest, FinalizesLargeHeader) { |
| const size_t packet_mask_size = kUlpfecPacketMaskSizeLBitSet; |
| auto packet_mask = GeneratePacketMask(packet_mask_size, 0xabcd); |
| Packet written_packet; |
| written_packet.data.SetSize(kMediaPacketLength); |
| uint8_t* data = written_packet.data.MutableData(); |
| for (size_t i = 0; i < written_packet.data.size(); ++i) { |
| data[i] = i; |
| } |
| |
| UlpfecHeaderWriter writer; |
| const FecHeaderWriter::ProtectedStream protected_streams[] = { |
| {.ssrc = kMediaSsrc, |
| .seq_num_base = kMediaStartSeqNum, |
| .packet_mask = {packet_mask.get(), packet_mask_size}}}; |
| writer.FinalizeFecHeader(protected_streams, written_packet); |
| |
| const uint8_t* packet = written_packet.data.cdata(); |
| EXPECT_EQ(0x00, packet[0] & 0x80); // E bit. |
| EXPECT_EQ(0x40, packet[0] & 0x40); // L bit. |
| EXPECT_EQ(kMediaStartSeqNum, ByteReader<uint16_t>::ReadBigEndian(packet + 2)); |
| EXPECT_EQ( |
| static_cast<uint16_t>(kMediaPacketLength - kUlpfecHeaderSizeLBitSet), |
| ByteReader<uint16_t>::ReadBigEndian(packet + 10)); |
| EXPECT_EQ(0, memcmp(packet + kUlpfecPacketMaskOffset, packet_mask.get(), |
| packet_mask_size)); |
| } |
| |
| TEST(UlpfecHeaderWriterTest, CalculateSmallHeaderSize) { |
| const size_t packet_mask_size = kUlpfecPacketMaskSizeLBitClear; |
| auto packet_mask = GeneratePacketMask(packet_mask_size, 0xabcd); |
| |
| UlpfecHeaderWriter writer; |
| size_t min_packet_mask_size = |
| writer.MinPacketMaskSize(packet_mask.get(), packet_mask_size); |
| |
| EXPECT_EQ(kUlpfecPacketMaskSizeLBitClear, min_packet_mask_size); |
| EXPECT_EQ(kUlpfecHeaderSizeLBitClear, |
| writer.FecHeaderSize(min_packet_mask_size)); |
| } |
| |
| TEST(UlpfecHeaderWriterTest, CalculateLargeHeaderSize) { |
| const size_t packet_mask_size = kUlpfecPacketMaskSizeLBitSet; |
| auto packet_mask = GeneratePacketMask(packet_mask_size, 0xabcd); |
| |
| UlpfecHeaderWriter writer; |
| size_t min_packet_mask_size = |
| writer.MinPacketMaskSize(packet_mask.get(), packet_mask_size); |
| |
| EXPECT_EQ(kUlpfecPacketMaskSizeLBitSet, min_packet_mask_size); |
| EXPECT_EQ(kUlpfecHeaderSizeLBitSet, |
| writer.FecHeaderSize(min_packet_mask_size)); |
| } |
| |
| TEST(UlpfecHeaderReaderWriterTest, WriteAndReadSmallHeader) { |
| const size_t packet_mask_size = kUlpfecPacketMaskSizeLBitClear; |
| auto packet_mask = GeneratePacketMask(packet_mask_size, 0xabcd); |
| |
| auto written_packet = WriteHeader(packet_mask.get(), packet_mask_size); |
| auto read_packet = ReadHeader(*written_packet); |
| |
| VerifyHeaders(kUlpfecHeaderSizeLBitClear, packet_mask.get(), packet_mask_size, |
| *written_packet, *read_packet); |
| } |
| |
| TEST(UlpfecHeaderReaderWriterTest, WriteAndReadLargeHeader) { |
| const size_t packet_mask_size = kUlpfecPacketMaskSizeLBitSet; |
| auto packet_mask = GeneratePacketMask(packet_mask_size, 0xabcd); |
| |
| auto written_packet = WriteHeader(packet_mask.get(), packet_mask_size); |
| auto read_packet = ReadHeader(*written_packet); |
| |
| VerifyHeaders(kUlpfecHeaderSizeLBitSet, packet_mask.get(), packet_mask_size, |
| *written_packet, *read_packet); |
| } |
| |
| } // namespace webrtc |