| /* |
| * Copyright 2011 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 "p2p/base/dtls_transport.h" |
| |
| #include <algorithm> |
| #include <memory> |
| #include <set> |
| #include <utility> |
| |
| #include "api/dtls_transport_interface.h" |
| #include "p2p/base/fake_ice_transport.h" |
| #include "p2p/base/packet_transport_internal.h" |
| #include "rtc_base/checks.h" |
| #include "rtc_base/dscp.h" |
| #include "rtc_base/gunit.h" |
| #include "rtc_base/helpers.h" |
| #include "rtc_base/rtc_certificate.h" |
| #include "rtc_base/ssl_adapter.h" |
| #include "rtc_base/ssl_identity.h" |
| #include "rtc_base/ssl_stream_adapter.h" |
| |
| #define MAYBE_SKIP_TEST(feature) \ |
| if (!(rtc::SSLStreamAdapter::feature())) { \ |
| RTC_LOG(LS_INFO) << #feature " feature disabled... skipping"; \ |
| return; \ |
| } |
| |
| namespace cricket { |
| |
| static const size_t kPacketNumOffset = 8; |
| static const size_t kPacketHeaderLen = 12; |
| static const int kFakePacketId = 0x1234; |
| static const int kTimeout = 10000; |
| |
| static bool IsRtpLeadByte(uint8_t b) { |
| return ((b & 0xC0) == 0x80); |
| } |
| |
| // `modify_digest` is used to set modified fingerprints that are meant to fail |
| // validation. |
| void SetRemoteFingerprintFromCert( |
| DtlsTransport* transport, |
| const rtc::scoped_refptr<rtc::RTCCertificate>& cert, |
| bool modify_digest = false) { |
| std::unique_ptr<rtc::SSLFingerprint> fingerprint = |
| rtc::SSLFingerprint::CreateFromCertificate(*cert); |
| if (modify_digest) { |
| ++fingerprint->digest.MutableData()[0]; |
| } |
| // Even if digest is verified to be incorrect, should fail asynchrnously. |
| EXPECT_TRUE(transport->SetRemoteFingerprint( |
| fingerprint->algorithm, |
| reinterpret_cast<const uint8_t*>(fingerprint->digest.data()), |
| fingerprint->digest.size())); |
| } |
| |
| class DtlsTestClient : public sigslot::has_slots<> { |
| public: |
| explicit DtlsTestClient(const std::string& name) : name_(name) {} |
| void CreateCertificate(rtc::KeyType key_type) { |
| certificate_ = |
| rtc::RTCCertificate::Create(rtc::SSLIdentity::Create(name_, key_type)); |
| } |
| const rtc::scoped_refptr<rtc::RTCCertificate>& certificate() { |
| return certificate_; |
| } |
| void SetupMaxProtocolVersion(rtc::SSLProtocolVersion version) { |
| ssl_max_version_ = version; |
| } |
| // Set up fake ICE transport and real DTLS transport under test. |
| void SetupTransports(IceRole role, int async_delay_ms = 0) { |
| fake_ice_transport_.reset(new FakeIceTransport("fake", 0)); |
| fake_ice_transport_->SetAsync(true); |
| fake_ice_transport_->SetAsyncDelay(async_delay_ms); |
| fake_ice_transport_->SetIceRole(role); |
| fake_ice_transport_->SetIceTiebreaker((role == ICEROLE_CONTROLLING) ? 1 |
| : 2); |
| // Hook the raw packets so that we can verify they are encrypted. |
| fake_ice_transport_->SignalReadPacket.connect( |
| this, &DtlsTestClient::OnFakeIceTransportReadPacket); |
| |
| dtls_transport_ = std::make_unique<DtlsTransport>( |
| fake_ice_transport_.get(), webrtc::CryptoOptions(), |
| /*event_log=*/nullptr, ssl_max_version_); |
| // Note: Certificate may be null here if testing passthrough. |
| dtls_transport_->SetLocalCertificate(certificate_); |
| dtls_transport_->SignalWritableState.connect( |
| this, &DtlsTestClient::OnTransportWritableState); |
| dtls_transport_->SignalReadPacket.connect( |
| this, &DtlsTestClient::OnTransportReadPacket); |
| dtls_transport_->SignalSentPacket.connect( |
| this, &DtlsTestClient::OnTransportSentPacket); |
| } |
| |
| FakeIceTransport* fake_ice_transport() { |
| return static_cast<FakeIceTransport*>(dtls_transport_->ice_transport()); |
| } |
| |
| DtlsTransport* dtls_transport() { return dtls_transport_.get(); } |
| |
| // Simulate fake ICE transports connecting. |
| bool Connect(DtlsTestClient* peer, bool asymmetric) { |
| fake_ice_transport()->SetDestination(peer->fake_ice_transport(), |
| asymmetric); |
| return true; |
| } |
| |
| int received_dtls_client_hellos() const { |
| return received_dtls_client_hellos_; |
| } |
| |
| int received_dtls_server_hellos() const { |
| return received_dtls_server_hellos_; |
| } |
| |
| void CheckRole(rtc::SSLRole role) { |
| if (role == rtc::SSL_CLIENT) { |
| ASSERT_EQ(0, received_dtls_client_hellos_); |
| ASSERT_GT(received_dtls_server_hellos_, 0); |
| } else { |
| ASSERT_GT(received_dtls_client_hellos_, 0); |
| ASSERT_EQ(0, received_dtls_server_hellos_); |
| } |
| } |
| |
| void CheckSrtp(int expected_crypto_suite) { |
| int crypto_suite; |
| bool rv = dtls_transport_->GetSrtpCryptoSuite(&crypto_suite); |
| if (dtls_transport_->IsDtlsActive() && expected_crypto_suite) { |
| ASSERT_TRUE(rv); |
| ASSERT_EQ(crypto_suite, expected_crypto_suite); |
| } else { |
| ASSERT_FALSE(rv); |
| } |
| } |
| |
| void CheckSsl() { |
| int cipher; |
| bool rv = dtls_transport_->GetSslCipherSuite(&cipher); |
| if (dtls_transport_->IsDtlsActive()) { |
| ASSERT_TRUE(rv); |
| EXPECT_TRUE( |
| rtc::SSLStreamAdapter::IsAcceptableCipher(cipher, rtc::KT_DEFAULT)); |
| } else { |
| ASSERT_FALSE(rv); |
| } |
| } |
| |
| void SendPackets(size_t size, size_t count, bool srtp) { |
| std::unique_ptr<char[]> packet(new char[size]); |
| size_t sent = 0; |
| do { |
| // Fill the packet with a known value and a sequence number to check |
| // against, and make sure that it doesn't look like DTLS. |
| memset(packet.get(), sent & 0xff, size); |
| packet[0] = (srtp) ? 0x80 : 0x00; |
| rtc::SetBE32(packet.get() + kPacketNumOffset, |
| static_cast<uint32_t>(sent)); |
| |
| // Only set the bypass flag if we've activated DTLS. |
| int flags = (certificate_ && srtp) ? PF_SRTP_BYPASS : 0; |
| rtc::PacketOptions packet_options; |
| packet_options.packet_id = kFakePacketId; |
| int rv = dtls_transport_->SendPacket(packet.get(), size, packet_options, |
| flags); |
| ASSERT_GT(rv, 0); |
| ASSERT_EQ(size, static_cast<size_t>(rv)); |
| ++sent; |
| } while (sent < count); |
| } |
| |
| int SendInvalidSrtpPacket(size_t size) { |
| std::unique_ptr<char[]> packet(new char[size]); |
| // Fill the packet with 0 to form an invalid SRTP packet. |
| memset(packet.get(), 0, size); |
| |
| rtc::PacketOptions packet_options; |
| return dtls_transport_->SendPacket(packet.get(), size, packet_options, |
| PF_SRTP_BYPASS); |
| } |
| |
| void ExpectPackets(size_t size) { |
| packet_size_ = size; |
| received_.clear(); |
| } |
| |
| size_t NumPacketsReceived() { return received_.size(); } |
| |
| // Inverse of SendPackets. |
| bool VerifyPacket(const char* data, size_t size, uint32_t* out_num) { |
| if (size != packet_size_ || |
| (data[0] != 0 && static_cast<uint8_t>(data[0]) != 0x80)) { |
| return false; |
| } |
| uint32_t packet_num = rtc::GetBE32(data + kPacketNumOffset); |
| for (size_t i = kPacketHeaderLen; i < size; ++i) { |
| if (static_cast<uint8_t>(data[i]) != (packet_num & 0xff)) { |
| return false; |
| } |
| } |
| if (out_num) { |
| *out_num = packet_num; |
| } |
| return true; |
| } |
| bool VerifyEncryptedPacket(const char* data, size_t size) { |
| // This is an encrypted data packet; let's make sure it's mostly random; |
| // less than 10% of the bytes should be equal to the cleartext packet. |
| if (size <= packet_size_) { |
| return false; |
| } |
| uint32_t packet_num = rtc::GetBE32(data + kPacketNumOffset); |
| int num_matches = 0; |
| for (size_t i = kPacketNumOffset; i < size; ++i) { |
| if (static_cast<uint8_t>(data[i]) == (packet_num & 0xff)) { |
| ++num_matches; |
| } |
| } |
| return (num_matches < ((static_cast<int>(size) - 5) / 10)); |
| } |
| |
| // Transport callbacks |
| void OnTransportWritableState(rtc::PacketTransportInternal* transport) { |
| RTC_LOG(LS_INFO) << name_ << ": Transport '" << transport->transport_name() |
| << "' is writable"; |
| } |
| |
| void OnTransportReadPacket(rtc::PacketTransportInternal* transport, |
| const char* data, |
| size_t size, |
| const int64_t& /* packet_time_us */, |
| int flags) { |
| uint32_t packet_num = 0; |
| ASSERT_TRUE(VerifyPacket(data, size, &packet_num)); |
| received_.insert(packet_num); |
| // Only DTLS-SRTP packets should have the bypass flag set. |
| int expected_flags = |
| (certificate_ && IsRtpLeadByte(data[0])) ? PF_SRTP_BYPASS : 0; |
| ASSERT_EQ(expected_flags, flags); |
| } |
| |
| void OnTransportSentPacket(rtc::PacketTransportInternal* transport, |
| const rtc::SentPacket& sent_packet) { |
| sent_packet_ = sent_packet; |
| } |
| |
| rtc::SentPacket sent_packet() const { return sent_packet_; } |
| |
| // Hook into the raw packet stream to make sure DTLS packets are encrypted. |
| void OnFakeIceTransportReadPacket(rtc::PacketTransportInternal* transport, |
| const char* data, |
| size_t size, |
| const int64_t& /* packet_time_us */, |
| int flags) { |
| // Flags shouldn't be set on the underlying Transport packets. |
| ASSERT_EQ(0, flags); |
| |
| // Look at the handshake packets to see what role we played. |
| // Check that non-handshake packets are DTLS data or SRTP bypass. |
| if (data[0] == 22 && size > 17) { |
| if (data[13] == 1) { |
| ++received_dtls_client_hellos_; |
| } else if (data[13] == 2) { |
| ++received_dtls_server_hellos_; |
| } |
| } else if (dtls_transport_->IsDtlsActive() && |
| !(data[0] >= 20 && data[0] <= 22)) { |
| ASSERT_TRUE(data[0] == 23 || IsRtpLeadByte(data[0])); |
| if (data[0] == 23) { |
| ASSERT_TRUE(VerifyEncryptedPacket(data, size)); |
| } else if (IsRtpLeadByte(data[0])) { |
| ASSERT_TRUE(VerifyPacket(data, size, NULL)); |
| } |
| } |
| } |
| |
| private: |
| std::string name_; |
| rtc::scoped_refptr<rtc::RTCCertificate> certificate_; |
| std::unique_ptr<FakeIceTransport> fake_ice_transport_; |
| std::unique_ptr<DtlsTransport> dtls_transport_; |
| size_t packet_size_ = 0u; |
| std::set<int> received_; |
| rtc::SSLProtocolVersion ssl_max_version_ = rtc::SSL_PROTOCOL_DTLS_12; |
| int received_dtls_client_hellos_ = 0; |
| int received_dtls_server_hellos_ = 0; |
| rtc::SentPacket sent_packet_; |
| }; |
| |
| // Base class for DtlsTransportTest and DtlsEventOrderingTest, which |
| // inherit from different variants of ::testing::Test. |
| // |
| // Note that this test always uses a FakeClock, due to the `fake_clock_` member |
| // variable. |
| class DtlsTransportTestBase { |
| public: |
| DtlsTransportTestBase() : client1_("P1"), client2_("P2"), use_dtls_(false) {} |
| |
| void SetMaxProtocolVersions(rtc::SSLProtocolVersion c1, |
| rtc::SSLProtocolVersion c2) { |
| client1_.SetupMaxProtocolVersion(c1); |
| client2_.SetupMaxProtocolVersion(c2); |
| } |
| // If not called, DtlsTransport will be used in SRTP bypass mode. |
| void PrepareDtls(rtc::KeyType key_type) { |
| client1_.CreateCertificate(key_type); |
| client2_.CreateCertificate(key_type); |
| use_dtls_ = true; |
| } |
| |
| // This test negotiates DTLS parameters before the underlying transports are |
| // writable. DtlsEventOrderingTest is responsible for exercising differerent |
| // orderings. |
| bool Connect(bool client1_server = true) { |
| Negotiate(client1_server); |
| EXPECT_TRUE(client1_.Connect(&client2_, false)); |
| |
| EXPECT_TRUE_SIMULATED_WAIT(client1_.dtls_transport()->writable() && |
| client2_.dtls_transport()->writable(), |
| kTimeout, fake_clock_); |
| if (!client1_.dtls_transport()->writable() || |
| !client2_.dtls_transport()->writable()) |
| return false; |
| |
| // Check that we used the right roles. |
| if (use_dtls_) { |
| client1_.CheckRole(client1_server ? rtc::SSL_SERVER : rtc::SSL_CLIENT); |
| client2_.CheckRole(client1_server ? rtc::SSL_CLIENT : rtc::SSL_SERVER); |
| } |
| |
| if (use_dtls_) { |
| // Check that we negotiated the right ciphers. Since GCM ciphers are not |
| // negotiated by default, we should end up with kSrtpAes128CmSha1_80. |
| client1_.CheckSrtp(rtc::kSrtpAes128CmSha1_80); |
| client2_.CheckSrtp(rtc::kSrtpAes128CmSha1_80); |
| } else { |
| // If DTLS isn't actually being used, GetSrtpCryptoSuite should return |
| // false. |
| client1_.CheckSrtp(rtc::kSrtpInvalidCryptoSuite); |
| client2_.CheckSrtp(rtc::kSrtpInvalidCryptoSuite); |
| } |
| |
| client1_.CheckSsl(); |
| client2_.CheckSsl(); |
| |
| return true; |
| } |
| |
| void Negotiate(bool client1_server = true) { |
| client1_.SetupTransports(ICEROLE_CONTROLLING); |
| client2_.SetupTransports(ICEROLE_CONTROLLED); |
| client1_.dtls_transport()->SetDtlsRole(client1_server ? rtc::SSL_SERVER |
| : rtc::SSL_CLIENT); |
| client2_.dtls_transport()->SetDtlsRole(client1_server ? rtc::SSL_CLIENT |
| : rtc::SSL_SERVER); |
| if (client2_.certificate()) { |
| SetRemoteFingerprintFromCert(client1_.dtls_transport(), |
| client2_.certificate()); |
| } |
| if (client1_.certificate()) { |
| SetRemoteFingerprintFromCert(client2_.dtls_transport(), |
| client1_.certificate()); |
| } |
| } |
| |
| void TestTransfer(size_t size, size_t count, bool srtp) { |
| RTC_LOG(LS_INFO) << "Expect packets, size=" << size; |
| client2_.ExpectPackets(size); |
| client1_.SendPackets(size, count, srtp); |
| EXPECT_EQ_SIMULATED_WAIT(count, client2_.NumPacketsReceived(), kTimeout, |
| fake_clock_); |
| } |
| |
| protected: |
| rtc::ScopedFakeClock fake_clock_; |
| DtlsTestClient client1_; |
| DtlsTestClient client2_; |
| bool use_dtls_; |
| rtc::SSLProtocolVersion ssl_expected_version_; |
| }; |
| |
| class DtlsTransportTest : public DtlsTransportTestBase, |
| public ::testing::Test {}; |
| |
| // Connect without DTLS, and transfer RTP data. |
| TEST_F(DtlsTransportTest, TestTransferRtp) { |
| ASSERT_TRUE(Connect()); |
| TestTransfer(1000, 100, /*srtp=*/false); |
| } |
| |
| // Test that the SignalSentPacket signal is wired up. |
| TEST_F(DtlsTransportTest, TestSignalSentPacket) { |
| ASSERT_TRUE(Connect()); |
| // Sanity check default value (-1). |
| ASSERT_EQ(client1_.sent_packet().send_time_ms, -1); |
| TestTransfer(1000, 100, false); |
| // Check that we get the expected fake packet ID, and a time of 0 from the |
| // fake clock. |
| EXPECT_EQ(kFakePacketId, client1_.sent_packet().packet_id); |
| EXPECT_GE(client1_.sent_packet().send_time_ms, 0); |
| } |
| |
| // Connect without DTLS, and transfer SRTP data. |
| TEST_F(DtlsTransportTest, TestTransferSrtp) { |
| ASSERT_TRUE(Connect()); |
| TestTransfer(1000, 100, /*srtp=*/true); |
| } |
| |
| // Connect with DTLS, and transfer data over DTLS. |
| TEST_F(DtlsTransportTest, TestTransferDtls) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| ASSERT_TRUE(Connect()); |
| TestTransfer(1000, 100, /*srtp=*/false); |
| } |
| |
| // Connect with DTLS, combine multiple DTLS records into one packet. |
| // Our DTLS implementation doesn't do this, but other implementations may; |
| // see https://tools.ietf.org/html/rfc6347#section-4.1.1. |
| // This has caused interoperability problems with ORTCLib in the past. |
| TEST_F(DtlsTransportTest, TestTransferDtlsCombineRecords) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| ASSERT_TRUE(Connect()); |
| // Our DTLS implementation always sends one record per packet, so to simulate |
| // an endpoint that sends multiple records per packet, we configure the fake |
| // ICE transport to combine every two consecutive packets into a single |
| // packet. |
| FakeIceTransport* transport = client1_.fake_ice_transport(); |
| transport->combine_outgoing_packets(true); |
| TestTransfer(500, 100, /*srtp=*/false); |
| } |
| |
| class DtlsTransportVersionTest |
| : public DtlsTransportTestBase, |
| public ::testing::TestWithParam< |
| ::testing::tuple<rtc::SSLProtocolVersion, rtc::SSLProtocolVersion>> { |
| }; |
| |
| // Test that an acceptable cipher suite is negotiated when different versions |
| // of DTLS are supported. Note that it's IsAcceptableCipher that does the actual |
| // work. |
| TEST_P(DtlsTransportVersionTest, TestCipherSuiteNegotiation) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| SetMaxProtocolVersions(::testing::get<0>(GetParam()), |
| ::testing::get<1>(GetParam())); |
| ASSERT_TRUE(Connect()); |
| } |
| |
| // Will test every combination of 1.0/1.2 on the client and server. |
| INSTANTIATE_TEST_SUITE_P( |
| TestCipherSuiteNegotiation, |
| DtlsTransportVersionTest, |
| ::testing::Combine(::testing::Values(rtc::SSL_PROTOCOL_DTLS_10, |
| rtc::SSL_PROTOCOL_DTLS_12), |
| ::testing::Values(rtc::SSL_PROTOCOL_DTLS_10, |
| rtc::SSL_PROTOCOL_DTLS_12))); |
| |
| // Connect with DTLS, negotiating DTLS-SRTP, and transfer SRTP using bypass. |
| TEST_F(DtlsTransportTest, TestTransferDtlsSrtp) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| ASSERT_TRUE(Connect()); |
| TestTransfer(1000, 100, /*srtp=*/true); |
| } |
| |
| // Connect with DTLS-SRTP, transfer an invalid SRTP packet, and expects -1 |
| // returned. |
| TEST_F(DtlsTransportTest, TestTransferDtlsInvalidSrtpPacket) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| ASSERT_TRUE(Connect()); |
| EXPECT_EQ(-1, client1_.SendInvalidSrtpPacket(100)); |
| } |
| |
| // Create a single transport with DTLS, and send normal data and SRTP data on |
| // it. |
| TEST_F(DtlsTransportTest, TestTransferDtlsSrtpDemux) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| ASSERT_TRUE(Connect()); |
| TestTransfer(1000, 100, /*srtp=*/false); |
| TestTransfer(1000, 100, /*srtp=*/true); |
| } |
| |
| // Test transferring when the "answerer" has the server role. |
| TEST_F(DtlsTransportTest, TestTransferDtlsSrtpAnswererIsPassive) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| ASSERT_TRUE(Connect(/*client1_server=*/false)); |
| TestTransfer(1000, 100, /*srtp=*/true); |
| } |
| |
| // Test that renegotiation (setting same role and fingerprint again) can be |
| // started before the clients become connected in the first negotiation. |
| TEST_F(DtlsTransportTest, TestRenegotiateBeforeConnect) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| // Note: This is doing the same thing Connect normally does, minus some |
| // additional checks not relevant for this test. |
| Negotiate(); |
| Negotiate(); |
| EXPECT_TRUE(client1_.Connect(&client2_, false)); |
| EXPECT_TRUE_SIMULATED_WAIT(client1_.dtls_transport()->writable() && |
| client2_.dtls_transport()->writable(), |
| kTimeout, fake_clock_); |
| TestTransfer(1000, 100, true); |
| } |
| |
| // Test Certificates state after negotiation but before connection. |
| TEST_F(DtlsTransportTest, TestCertificatesBeforeConnect) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| Negotiate(); |
| |
| // After negotiation, each side has a distinct local certificate, but still no |
| // remote certificate, because connection has not yet occurred. |
| auto certificate1 = client1_.dtls_transport()->GetLocalCertificate(); |
| auto certificate2 = client2_.dtls_transport()->GetLocalCertificate(); |
| ASSERT_NE(certificate1->GetSSLCertificate().ToPEMString(), |
| certificate2->GetSSLCertificate().ToPEMString()); |
| ASSERT_FALSE(client1_.dtls_transport()->GetRemoteSSLCertChain()); |
| ASSERT_FALSE(client2_.dtls_transport()->GetRemoteSSLCertChain()); |
| } |
| |
| // Test Certificates state after connection. |
| TEST_F(DtlsTransportTest, TestCertificatesAfterConnect) { |
| PrepareDtls(rtc::KT_DEFAULT); |
| ASSERT_TRUE(Connect()); |
| |
| // After connection, each side has a distinct local certificate. |
| auto certificate1 = client1_.dtls_transport()->GetLocalCertificate(); |
| auto certificate2 = client2_.dtls_transport()->GetLocalCertificate(); |
| ASSERT_NE(certificate1->GetSSLCertificate().ToPEMString(), |
| certificate2->GetSSLCertificate().ToPEMString()); |
| |
| // Each side's remote certificate is the other side's local certificate. |
| std::unique_ptr<rtc::SSLCertChain> remote_cert1 = |
| client1_.dtls_transport()->GetRemoteSSLCertChain(); |
| ASSERT_TRUE(remote_cert1); |
| ASSERT_EQ(1u, remote_cert1->GetSize()); |
| ASSERT_EQ(remote_cert1->Get(0).ToPEMString(), |
| certificate2->GetSSLCertificate().ToPEMString()); |
| std::unique_ptr<rtc::SSLCertChain> remote_cert2 = |
| client2_.dtls_transport()->GetRemoteSSLCertChain(); |
| ASSERT_TRUE(remote_cert2); |
| ASSERT_EQ(1u, remote_cert2->GetSize()); |
| ASSERT_EQ(remote_cert2->Get(0).ToPEMString(), |
| certificate1->GetSSLCertificate().ToPEMString()); |
| } |
| |
| // Test that packets are retransmitted according to the expected schedule. |
| // Each time a timeout occurs, the retransmission timer should be doubled up to |
| // 60 seconds. The timer defaults to 1 second, but for WebRTC we should be |
| // initializing it to 50ms. |
| TEST_F(DtlsTransportTest, TestRetransmissionSchedule) { |
| // We can only change the retransmission schedule with a recently-added |
| // BoringSSL API. Skip the test if not built with BoringSSL. |
| MAYBE_SKIP_TEST(IsBoringSsl); |
| |
| PrepareDtls(rtc::KT_DEFAULT); |
| // Exchange fingerprints and set SSL roles. |
| Negotiate(); |
| |
| // Make client2_ writable, but not client1_. |
| // This means client1_ will send DTLS client hellos but get no response. |
| EXPECT_TRUE(client2_.Connect(&client1_, true)); |
| EXPECT_TRUE_SIMULATED_WAIT(client2_.fake_ice_transport()->writable(), |
| kTimeout, fake_clock_); |
| |
| // Wait for the first client hello to be sent. |
| EXPECT_EQ_WAIT(1, client1_.received_dtls_client_hellos(), kTimeout); |
| EXPECT_FALSE(client1_.fake_ice_transport()->writable()); |
| |
| static int timeout_schedule_ms[] = {50, 100, 200, 400, 800, 1600, |
| 3200, 6400, 12800, 25600, 51200, 60000}; |
| |
| int expected_hellos = 1; |
| for (size_t i = 0; |
| i < (sizeof(timeout_schedule_ms) / sizeof(timeout_schedule_ms[0])); |
| ++i) { |
| // For each expected retransmission time, advance the fake clock a |
| // millisecond before the expected time and verify that no unexpected |
| // retransmissions were sent. Then advance it the final millisecond and |
| // verify that the expected retransmission was sent. |
| fake_clock_.AdvanceTime( |
| webrtc::TimeDelta::Millis(timeout_schedule_ms[i] - 1)); |
| EXPECT_EQ(expected_hellos, client1_.received_dtls_client_hellos()); |
| fake_clock_.AdvanceTime(webrtc::TimeDelta::Millis(1)); |
| EXPECT_EQ(++expected_hellos, client1_.received_dtls_client_hellos()); |
| } |
| } |
| |
| // The following events can occur in many different orders: |
| // 1. Caller receives remote fingerprint. |
| // 2. Caller is writable. |
| // 3. Caller receives ClientHello. |
| // 4. DTLS handshake finishes. |
| // |
| // The tests below cover all causally consistent permutations of these events; |
| // the caller must be writable and receive a ClientHello before the handshake |
| // finishes, but otherwise any ordering is possible. |
| // |
| // For each permutation, the test verifies that a connection is established and |
| // fingerprint verified without any DTLS packet needing to be retransmitted. |
| // |
| // Each permutation is also tested with valid and invalid fingerprints, |
| // ensuring that the handshake fails with an invalid fingerprint. |
| enum DtlsTransportEvent { |
| CALLER_RECEIVES_FINGERPRINT, |
| CALLER_WRITABLE, |
| CALLER_RECEIVES_CLIENTHELLO, |
| HANDSHAKE_FINISHES |
| }; |
| |
| class DtlsEventOrderingTest |
| : public DtlsTransportTestBase, |
| public ::testing::TestWithParam< |
| ::testing::tuple<std::vector<DtlsTransportEvent>, bool>> { |
| protected: |
| // If `valid_fingerprint` is false, the caller will receive a fingerprint |
| // that doesn't match the callee's certificate, so the handshake should fail. |
| void TestEventOrdering(const std::vector<DtlsTransportEvent>& events, |
| bool valid_fingerprint) { |
| // Pre-setup: Set local certificate on both caller and callee, and |
| // remote fingerprint on callee, but neither is writable and the caller |
| // doesn't have the callee's fingerprint. |
| PrepareDtls(rtc::KT_DEFAULT); |
| // Simulate packets being sent and arriving asynchronously. |
| // Otherwise the entire DTLS handshake would occur in one clock tick, and |
| // we couldn't inject method calls in the middle of it. |
| int simulated_delay_ms = 10; |
| client1_.SetupTransports(ICEROLE_CONTROLLING, simulated_delay_ms); |
| client2_.SetupTransports(ICEROLE_CONTROLLED, simulated_delay_ms); |
| // Similar to how NegotiateOrdering works. |
| client1_.dtls_transport()->SetDtlsRole(rtc::SSL_SERVER); |
| client2_.dtls_transport()->SetDtlsRole(rtc::SSL_CLIENT); |
| SetRemoteFingerprintFromCert(client2_.dtls_transport(), |
| client1_.certificate()); |
| |
| for (DtlsTransportEvent e : events) { |
| switch (e) { |
| case CALLER_RECEIVES_FINGERPRINT: |
| if (valid_fingerprint) { |
| SetRemoteFingerprintFromCert(client1_.dtls_transport(), |
| client2_.certificate()); |
| } else { |
| SetRemoteFingerprintFromCert(client1_.dtls_transport(), |
| client2_.certificate(), |
| true /*modify_digest*/); |
| } |
| break; |
| case CALLER_WRITABLE: |
| EXPECT_TRUE(client1_.Connect(&client2_, true)); |
| EXPECT_TRUE_SIMULATED_WAIT(client1_.fake_ice_transport()->writable(), |
| kTimeout, fake_clock_); |
| break; |
| case CALLER_RECEIVES_CLIENTHELLO: |
| // Sanity check that a ClientHello hasn't already been received. |
| EXPECT_EQ(0, client1_.received_dtls_client_hellos()); |
| // Making client2_ writable will cause it to send the ClientHello. |
| EXPECT_TRUE(client2_.Connect(&client1_, true)); |
| EXPECT_TRUE_SIMULATED_WAIT(client2_.fake_ice_transport()->writable(), |
| kTimeout, fake_clock_); |
| EXPECT_EQ_SIMULATED_WAIT(1, client1_.received_dtls_client_hellos(), |
| kTimeout, fake_clock_); |
| break; |
| case HANDSHAKE_FINISHES: |
| // Sanity check that the handshake hasn't already finished. |
| EXPECT_FALSE(client1_.dtls_transport()->IsDtlsConnected() || |
| client1_.dtls_transport()->dtls_state() == |
| webrtc::DtlsTransportState::kFailed); |
| EXPECT_TRUE_SIMULATED_WAIT( |
| client1_.dtls_transport()->IsDtlsConnected() || |
| client1_.dtls_transport()->dtls_state() == |
| webrtc::DtlsTransportState::kFailed, |
| kTimeout, fake_clock_); |
| break; |
| } |
| } |
| |
| webrtc::DtlsTransportState expected_final_state = |
| valid_fingerprint ? webrtc::DtlsTransportState::kConnected |
| : webrtc::DtlsTransportState::kFailed; |
| EXPECT_EQ_SIMULATED_WAIT(expected_final_state, |
| client1_.dtls_transport()->dtls_state(), kTimeout, |
| fake_clock_); |
| EXPECT_EQ_SIMULATED_WAIT(expected_final_state, |
| client2_.dtls_transport()->dtls_state(), kTimeout, |
| fake_clock_); |
| |
| // Transports should be writable iff there was a valid fingerprint. |
| EXPECT_EQ(valid_fingerprint, client1_.dtls_transport()->writable()); |
| EXPECT_EQ(valid_fingerprint, client2_.dtls_transport()->writable()); |
| |
| // Check that no hello needed to be retransmitted. |
| EXPECT_EQ(1, client1_.received_dtls_client_hellos()); |
| EXPECT_EQ(1, client2_.received_dtls_server_hellos()); |
| |
| if (valid_fingerprint) { |
| TestTransfer(1000, 100, false); |
| } |
| } |
| }; |
| |
| TEST_P(DtlsEventOrderingTest, TestEventOrdering) { |
| TestEventOrdering(::testing::get<0>(GetParam()), |
| ::testing::get<1>(GetParam())); |
| } |
| |
| INSTANTIATE_TEST_SUITE_P( |
| TestEventOrdering, |
| DtlsEventOrderingTest, |
| ::testing::Combine( |
| ::testing::Values( |
| std::vector<DtlsTransportEvent>{ |
| CALLER_RECEIVES_FINGERPRINT, CALLER_WRITABLE, |
| CALLER_RECEIVES_CLIENTHELLO, HANDSHAKE_FINISHES}, |
| std::vector<DtlsTransportEvent>{ |
| CALLER_WRITABLE, CALLER_RECEIVES_FINGERPRINT, |
| CALLER_RECEIVES_CLIENTHELLO, HANDSHAKE_FINISHES}, |
| std::vector<DtlsTransportEvent>{ |
| CALLER_WRITABLE, CALLER_RECEIVES_CLIENTHELLO, |
| CALLER_RECEIVES_FINGERPRINT, HANDSHAKE_FINISHES}, |
| std::vector<DtlsTransportEvent>{ |
| CALLER_WRITABLE, CALLER_RECEIVES_CLIENTHELLO, |
| HANDSHAKE_FINISHES, CALLER_RECEIVES_FINGERPRINT}, |
| std::vector<DtlsTransportEvent>{ |
| CALLER_RECEIVES_FINGERPRINT, CALLER_RECEIVES_CLIENTHELLO, |
| CALLER_WRITABLE, HANDSHAKE_FINISHES}, |
| std::vector<DtlsTransportEvent>{ |
| CALLER_RECEIVES_CLIENTHELLO, CALLER_RECEIVES_FINGERPRINT, |
| CALLER_WRITABLE, HANDSHAKE_FINISHES}, |
| std::vector<DtlsTransportEvent>{ |
| CALLER_RECEIVES_CLIENTHELLO, CALLER_WRITABLE, |
| CALLER_RECEIVES_FINGERPRINT, HANDSHAKE_FINISHES}, |
| std::vector<DtlsTransportEvent>{CALLER_RECEIVES_CLIENTHELLO, |
| CALLER_WRITABLE, HANDSHAKE_FINISHES, |
| CALLER_RECEIVES_FINGERPRINT}), |
| ::testing::Bool())); |
| |
| } // namespace cricket |
