quic/core/crypto/quic_client_session_cache_test.cc - quiche - Git at Google

 // Copyright (c) 2021 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 "quic/core/crypto/quic_client_session_cache.h"

 #include "quic/platform/api/quic_test.h"
 #include "quic/test_tools/mock_clock.h"
 #include "common/quiche_text_utils.h"

 namespace quic {
 namespace test {
 namespace {

 const QuicTime::Delta kTimeout = QuicTime::Delta::FromSeconds(1000);
 const QuicVersionLabel kFakeVersionLabel = 0x01234567;
 const QuicVersionLabel kFakeVersionLabel2 = 0x89ABCDEF;
 const uint64_t kFakeIdleTimeoutMilliseconds = 12012;
 const uint8_t kFakeStatelessResetTokenData[16] = {
     0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
     0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F};
 const uint64_t kFakeMaxPacketSize = 9001;
 const uint64_t kFakeInitialMaxData = 101;
 const bool kFakeDisableMigration = true;
 const auto kCustomParameter1 =
     static_cast<TransportParameters::TransportParameterId>(0xffcd);
 const char* kCustomParameter1Value = "foo";
 const auto kCustomParameter2 =
     static_cast<TransportParameters::TransportParameterId>(0xff34);
 const char* kCustomParameter2Value = "bar";

 std::vector<uint8_t> CreateFakeStatelessResetToken() {
   return std::vector<uint8_t>(
       kFakeStatelessResetTokenData,
       kFakeStatelessResetTokenData + sizeof(kFakeStatelessResetTokenData));
 }

 TransportParameters::LegacyVersionInformation
 CreateFakeLegacyVersionInformation() {
   TransportParameters::LegacyVersionInformation legacy_version_information;
   legacy_version_information.version = kFakeVersionLabel;
   legacy_version_information.supported_versions.push_back(kFakeVersionLabel);
   legacy_version_information.supported_versions.push_back(kFakeVersionLabel2);
   return legacy_version_information;
 }

 TransportParameters::VersionInformation CreateFakeVersionInformation() {
   TransportParameters::VersionInformation version_information;
   version_information.chosen_version = kFakeVersionLabel;
   version_information.other_versions.push_back(kFakeVersionLabel);
   return version_information;
 }

 // Make a TransportParameters that has a few fields set to help test comparison.
 std::unique_ptr<TransportParameters> MakeFakeTransportParams() {
   auto params = std::make_unique<TransportParameters>();
   params->perspective = Perspective::IS_CLIENT;
   params->legacy_version_information = CreateFakeLegacyVersionInformation();
   params->version_information = CreateFakeVersionInformation();
   params->max_idle_timeout_ms.set_value(kFakeIdleTimeoutMilliseconds);
   params->stateless_reset_token = CreateFakeStatelessResetToken();
   params->max_udp_payload_size.set_value(kFakeMaxPacketSize);
   params->initial_max_data.set_value(kFakeInitialMaxData);
   params->disable_active_migration = kFakeDisableMigration;
   params->custom_parameters[kCustomParameter1] = kCustomParameter1Value;
   params->custom_parameters[kCustomParameter2] = kCustomParameter2Value;
   return params;
 }

 // Generated by running TlsClientHandshakerTest.ZeroRttResumption and in
 // TlsClientHandshaker::InsertSession calling SSL_SESSION_to_bytes to serialize
 // the received 0-RTT capable ticket.
 static const char kCachedSession[] =
     "30820ad7020101020203040402130104206594ce84e61a866b56163c4ba09079aebf1d4f"
     "6cbcbd38dc9d7066a38a76c9cf0420ec9062063582a4cc0a44f9ff93256a195153ba6032"
     "0cf3c9189990932d838adaa10602046196f7b9a205020302a300a382039f3082039b3082"
     "0183a00302010202021001300d06092a864886f70d010105050030623111300f06035504"
     "030c08426f677573204941310b300906035504080c024d41310b30090603550406130255"
     "533121301f06092a864886f70d0109011612626f67757340626f6775732d69612e636f6d"
     "3110300e060355040a0c07426f6775734941301e170d3231303132383136323030315a17"
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     "6578616d706c652e636f6d310b300906035504080c024d41310b30090603550406130255"
     "53311e301c06092a864886f70d010901160f626f67757340626f6775732e636f6d310e30"
     "0c060355040a0c05426f6775733059301306072a8648ce3d020106082a8648ce3d030107"
     "034200041ba5e2b6f24e64990b9f24ae6d23473d8c77fbcfb7f554f36559529a69a57170"
     "a10a81b7fe4a36ebf37b0a8c5e467a8443d8b8c002892aa5c1194bd843f42c9aa31f301d"
     "301b0603551d11041430128210746573742e6578616d706c652e636f6d300d06092a8648"
     "86f70d0101050500038202010019921d54ac06948763d609215f64f5d6540e3da886c6c9"
     "61bc737a437719b4621416ef1229f39282d7d3234e1a5d57535473066233bd246eec8e96"
     "1e0633cf4fe014c800e62599981820ec33d92e74ded0fa2953db1d81e19cb6890b6305b6"
     "3ede8d3e9fcf3c09f3f57283acf08aa57be4ee9a68d00bb3e2ded5920c619b5d83e5194a"
     "adb77ae5d61ed3e0a5670f0ae61cc3197329f0e71e3364dcab0405e9e4a6646adef8f022"
     "6415ec16c8046307b1769029fe780bd576114dde2fa9b4a32aa70bc436549a24ee4907a9"
     "045f6457ce8dfd8d62cc65315afe798ae1a948eefd70b035d415e73569c48fb20085de1a"
     "87de039e6b0b9a5fcb4069df27f3a7a1409e72d1ac739c72f29ef786134207e61c79855f"
     "c22e3ee5f6ad59a7b1ff0f18d79776f1c95efaebbebe381664132a58a1e7ff689945b7e0"
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     "55524500f3439e548c21d2ad6e5634cc1cc0045730819702010102020304040213010400"
     "0420ec9062063582a4cc0a44f9ff93256a195153ba60320cf3c9189990932d838adaa106"
     "02046196f7b9a205020302a300a4020400b20302011db5060404130800cdb807020500ff"
     "ffffffb9050203093a80ba0404026833bb030101ffbc23042100d27d985bfce04833f02d"
     "38366b219f4def42bc4ba1b01844d1778db11731487dbd020400be020400b20302011db3"
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     "383136313935385a180f32303730303531313136313935385a30623111300f0603550403"
     "0c08426f677573204941310b300906035504080c024d41310b3009060355040613025553"
     "3121301f06092a864886f70d0109011612626f67757340626f6775732d69612e636f6d31"
     "10300e060355040a0c07426f677573494130820222300d06092a864886f70d0101010500"
     "0382020f003082020a028202010096c03a0ffc61bcedcd5ec9bf6f848b8a066b43f08377"
     "3af518a6a0044f22e666e24d2ae741954e344302c4be04612185bd53bcd848eb322bf900"
     "724eb0848047d647033ffbddb00f01d1de7c1cdb684f83c9bf5fd18ff60afad5a53b0d7d"
     "2c2a50abc38df019cd7f50194d05bc4597a1ef8570ea04069a2c36d74496af126573ca18"
     "8e470009b56250fadf2a04e837ee3837b36b1f08b7a0cfe2533d05f26484ce4e30203d01"
     "517fffd3da63d0341079ddce16e9ab4dbf9d4049e5cc52326031e645dd682fe6220d9e0e"
     "95451f5a82f3e1720dc13e8499466426a0bdbea9f6a76b3c9228dd3c79ab4dcc4c145ef0"
     "e78d1ee8bfd4650692d7e28a54bed809d8f7b37fe24c586be59cc46638531cb291c8c156"
     "8f08d67e768e51563e95a639c1f138b275ffad6a6a2a042ba9e26ad63c2ce63b600013f0"
     "a6f0703ee51c4f457f7bab0391c2fc4c5bb3213742c9cf9941bff68cc2e1cc96139d35ed"
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     "068ab9b3486cd839d6301f0603551d23041830168014780beeefe2fa419c48a438bdb30b"
     "e37ef0b7a94e300b0603551d0f0404030202a430130603551d25040c300a06082b060105"
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     "5a5a599ea305349f1b0e545a00817d6e55c7bf85560fab429ca72186c4d520b52f5cc121"
     "abd068b06f3111494431d2522efa54642f907059e7db80b73bb5ecf621377195b8700bba"
     "df798cece8c67a9571548d0e6592e81ae5d934877cb170aef18d3b97f635600fe0890d98"
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     "68875f052c9271648d9cb54687c6fdc3ea96f2908003bc5e5e79de00a21da7b8429f8b08"
     "af4c4d34641e386d72eabf5f01f106363f2ffd18969bf0bb9a4d17627c6427ff772c4308"
     "83c276feef5fc6dba9582c22fdbe9df7e8dfca375695f028ed588df54f3c86462dbf4c07"
     "91d80ca738988a1419c86bb4dd8d738b746921f01f39422e5ffd488b6f00195b996e6392"
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     "22c7aef1af1fbcb23e93ae7622ab1ee11fcfa98319bad4c37c091cad46bd0337b3cc78b5"
     "5b9f1ea7994acc1f89c49a0b4cb540d2137e266fd43e56a9b5b778217b6f77df530e1eaf"
     "b3417262b5ddb86d3c6c5ac51e3f326c650dcc2434473973b7182c66220d1f3871bde7ee"
     "47d3f359d3d4c5bdd61baa684c03db4c75f9d6690c9e6e3abe6eaf5fa2c33c4daf26b373"
     "d85a1e8a7d671ac4a0a97b14e36e81280de4593bbb12da7695b5060404130800cdb60301"
     "0100b70402020403b807020500ffffffffb9050203093a80ba0404026833bb030101ffbd"
     "020400be020400";

 class QuicClientSessionCacheTest : public QuicTest {
  public:
   QuicClientSessionCacheTest() : ssl_ctx_(SSL_CTX_new(TLS_method())) {
     clock_.AdvanceTime(QuicTime::Delta::FromSeconds(1));
   }

  protected:
   bssl::UniquePtr<SSL_SESSION> NewSSLSession() {
     std::string cached_session =
         absl::HexStringToBytes(absl::string_view(kCachedSession));
     SSL_SESSION* session = SSL_SESSION_from_bytes(
         reinterpret_cast<const uint8_t*>(cached_session.data()),
         cached_session.size(), ssl_ctx_.get());
     QUICHE_DCHECK(session);
     return bssl::UniquePtr<SSL_SESSION>(session);
   }

   bssl::UniquePtr<SSL_SESSION> MakeTestSession(
       QuicTime::Delta timeout = kTimeout) {
     bssl::UniquePtr<SSL_SESSION> session = NewSSLSession();
     SSL_SESSION_set_time(session.get(), clock_.WallNow().ToUNIXSeconds());
     SSL_SESSION_set_timeout(session.get(), timeout.ToSeconds());
     return session;
   }

   bssl::UniquePtr<SSL_CTX> ssl_ctx_;
   MockClock clock_;
 };

 // Tests that simple insertion and lookup work correctly.
 TEST_F(QuicClientSessionCacheTest, SingleSession) {
   QuicClientSessionCache cache;

   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   QuicServerId id1("a.com", 443);

   auto params2 = MakeFakeTransportParams();
   auto session2 = MakeTestSession();
   SSL_SESSION* unowned2 = session2.get();
   QuicServerId id2("b.com", 443);

   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
   EXPECT_EQ(nullptr, cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get()));
   EXPECT_EQ(0u, cache.size());

   cache.Insert(id1, std::move(session), *params, nullptr);
   EXPECT_EQ(1u, cache.size());
   EXPECT_EQ(
       *params,
       *(cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get())->transport_params));
   EXPECT_EQ(nullptr, cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get()));
   // No session is available for id1, even though the entry exists.
   EXPECT_EQ(1u, cache.size());
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
   // Lookup() will trigger a deletion of invalid entry.
   EXPECT_EQ(0u, cache.size());

   auto session3 = MakeTestSession();
   SSL_SESSION* unowned3 = session3.get();
   QuicServerId id3("c.com", 443);
   cache.Insert(id3, std::move(session3), *params, nullptr);
   cache.Insert(id2, std::move(session2), *params2, nullptr);
   EXPECT_EQ(2u, cache.size());
   EXPECT_EQ(
       unowned2,
       cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
   EXPECT_EQ(
       unowned3,
       cache.Lookup(id3, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());

   // Verify that the cache is cleared after Lookups.
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
   EXPECT_EQ(nullptr, cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get()));
   EXPECT_EQ(nullptr, cache.Lookup(id3, clock_.WallNow(), ssl_ctx_.get()));
   EXPECT_EQ(0u, cache.size());
 }

 TEST_F(QuicClientSessionCacheTest, MultipleSessions) {
   QuicClientSessionCache cache;

   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   QuicServerId id1("a.com", 443);
   auto session2 = MakeTestSession();
   SSL_SESSION* unowned2 = session2.get();
   auto session3 = MakeTestSession();
   SSL_SESSION* unowned3 = session3.get();

   cache.Insert(id1, std::move(session), *params, nullptr);
   cache.Insert(id1, std::move(session2), *params, nullptr);
   cache.Insert(id1, std::move(session3), *params, nullptr);
   // The latest session is popped first.
   EXPECT_EQ(
       unowned3,
       cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
   EXPECT_EQ(
       unowned2,
       cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
   // Only two sessions are cached.
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
 }

 // Test that when a different TransportParameter is inserted for
 // the same server id, the existing entry is removed.
 TEST_F(QuicClientSessionCacheTest, DifferentTransportParams) {
   QuicClientSessionCache cache;

   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   QuicServerId id1("a.com", 443);
   auto session2 = MakeTestSession();
   auto session3 = MakeTestSession();
   SSL_SESSION* unowned3 = session3.get();

   cache.Insert(id1, std::move(session), *params, nullptr);
   cache.Insert(id1, std::move(session2), *params, nullptr);
   // tweak the transport parameters a little bit.
   params->perspective = Perspective::IS_SERVER;
   cache.Insert(id1, std::move(session3), *params, nullptr);
   auto resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
   EXPECT_EQ(unowned3, resumption_state->tls_session.get());
   EXPECT_EQ(*params.get(), *resumption_state->transport_params);
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
 }

 TEST_F(QuicClientSessionCacheTest, DifferentApplicationState) {
   QuicClientSessionCache cache;

   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   QuicServerId id1("a.com", 443);
   auto session2 = MakeTestSession();
   auto session3 = MakeTestSession();
   SSL_SESSION* unowned3 = session3.get();
   ApplicationState state;
   state.push_back('a');

   cache.Insert(id1, std::move(session), *params, &state);
   cache.Insert(id1, std::move(session2), *params, &state);
   cache.Insert(id1, std::move(session3), *params, nullptr);
   auto resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
   EXPECT_EQ(unowned3, resumption_state->tls_session.get());
   EXPECT_EQ(nullptr, resumption_state->application_state);
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
 }

 TEST_F(QuicClientSessionCacheTest, BothStatesDifferent) {
   QuicClientSessionCache cache;

   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   QuicServerId id1("a.com", 443);
   auto session2 = MakeTestSession();
   auto session3 = MakeTestSession();
   SSL_SESSION* unowned3 = session3.get();
   ApplicationState state;
   state.push_back('a');

   cache.Insert(id1, std::move(session), *params, &state);
   cache.Insert(id1, std::move(session2), *params, &state);
   params->perspective = Perspective::IS_SERVER;
   cache.Insert(id1, std::move(session3), *params, nullptr);
   auto resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
   EXPECT_EQ(unowned3, resumption_state->tls_session.get());
   EXPECT_EQ(*params.get(), *resumption_state->transport_params);
   EXPECT_EQ(nullptr, resumption_state->application_state);
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
 }

 // When the size limit is exceeded, the oldest entry should be erased.
 TEST_F(QuicClientSessionCacheTest, SizeLimit) {
   QuicClientSessionCache cache(2);

   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   QuicServerId id1("a.com", 443);

   auto session2 = MakeTestSession();
   SSL_SESSION* unowned2 = session2.get();
   QuicServerId id2("b.com", 443);

   auto session3 = MakeTestSession();
   SSL_SESSION* unowned3 = session3.get();
   QuicServerId id3("c.com", 443);

   cache.Insert(id1, std::move(session), *params, nullptr);
   cache.Insert(id2, std::move(session2), *params, nullptr);
   cache.Insert(id3, std::move(session3), *params, nullptr);

   EXPECT_EQ(2u, cache.size());
   EXPECT_EQ(
       unowned2,
       cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
   EXPECT_EQ(
       unowned3,
       cache.Lookup(id3, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
 }

 TEST_F(QuicClientSessionCacheTest, ClearEarlyData) {
   QuicClientSessionCache cache;
   SSL_CTX_set_early_data_enabled(ssl_ctx_.get(), 1);
   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   QuicServerId id1("a.com", 443);
   auto session2 = MakeTestSession();

   EXPECT_TRUE(SSL_SESSION_early_data_capable(session.get()));
   EXPECT_TRUE(SSL_SESSION_early_data_capable(session2.get()));

   cache.Insert(id1, std::move(session), *params, nullptr);
   cache.Insert(id1, std::move(session2), *params, nullptr);

   cache.ClearEarlyData(id1);

   auto resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
   EXPECT_FALSE(
       SSL_SESSION_early_data_capable(resumption_state->tls_session.get()));
   resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
   EXPECT_FALSE(
       SSL_SESSION_early_data_capable(resumption_state->tls_session.get()));
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
 }

 // Expired session isn't considered valid and nullptr will be returned upon
 // Lookup.
 TEST_F(QuicClientSessionCacheTest, Expiration) {
   QuicClientSessionCache cache;

   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   QuicServerId id1("a.com", 443);

   auto session2 = MakeTestSession(3 * kTimeout);
   SSL_SESSION* unowned2 = session2.get();
   QuicServerId id2("b.com", 443);

   cache.Insert(id1, std::move(session), *params, nullptr);
   cache.Insert(id2, std::move(session2), *params, nullptr);

   EXPECT_EQ(2u, cache.size());
   // Expire the session.
   clock_.AdvanceTime(kTimeout * 2);
   // The entry has not been removed yet.
   EXPECT_EQ(2u, cache.size());

   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
   EXPECT_EQ(1u, cache.size());
   EXPECT_EQ(
       unowned2,
       cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
   EXPECT_EQ(1u, cache.size());
 }

 TEST_F(QuicClientSessionCacheTest, RemoveExpiredEntriesAndClear) {
   QuicClientSessionCache cache;

   auto params = MakeFakeTransportParams();
   auto session = MakeTestSession();
   quic::QuicServerId id1("a.com", 443);

   auto session2 = MakeTestSession(3 * kTimeout);
   quic::QuicServerId id2("b.com", 443);

   cache.Insert(id1, std::move(session), *params, nullptr);
   cache.Insert(id2, std::move(session2), *params, nullptr);

   EXPECT_EQ(2u, cache.size());
   // Expire the session.
   clock_.AdvanceTime(kTimeout * 2);
   // The entry has not been removed yet.
   EXPECT_EQ(2u, cache.size());

   // Flush expired sessions.
   cache.RemoveExpiredEntries(clock_.WallNow());

   // session is expired and should be flushed.
   EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
   EXPECT_EQ(1u, cache.size());

   cache.Clear();
   EXPECT_EQ(0u, cache.size());
 }

 }  // namespace
 }  // namespace test
 }  // namespace quic
	// Copyright (c) 2021 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 "quic/core/crypto/quic_client_session_cache.h"

	#include "quic/platform/api/quic_test.h"
	#include "quic/test_tools/mock_clock.h"
	#include "common/quiche_text_utils.h"

	namespace quic {
	namespace test {
	namespace {

	const QuicTime::Delta kTimeout = QuicTime::Delta::FromSeconds(1000);
	const QuicVersionLabel kFakeVersionLabel = 0x01234567;
	const QuicVersionLabel kFakeVersionLabel2 = 0x89ABCDEF;
	const uint64_t kFakeIdleTimeoutMilliseconds = 12012;
	const uint8_t kFakeStatelessResetTokenData[16] = {
	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
	0x98, 0x99, 0x9A, 0x9B, 0x9C, 0x9D, 0x9E, 0x9F};
	const uint64_t kFakeMaxPacketSize = 9001;
	const uint64_t kFakeInitialMaxData = 101;
	const bool kFakeDisableMigration = true;
	const auto kCustomParameter1 =
	static_cast<TransportParameters::TransportParameterId>(0xffcd);
	const char* kCustomParameter1Value = "foo";
	const auto kCustomParameter2 =
	static_cast<TransportParameters::TransportParameterId>(0xff34);
	const char* kCustomParameter2Value = "bar";

	std::vector<uint8_t> CreateFakeStatelessResetToken() {
	return std::vector<uint8_t>(
	kFakeStatelessResetTokenData,
	kFakeStatelessResetTokenData + sizeof(kFakeStatelessResetTokenData));
	}

	TransportParameters::LegacyVersionInformation
	CreateFakeLegacyVersionInformation() {
	TransportParameters::LegacyVersionInformation legacy_version_information;
	legacy_version_information.version = kFakeVersionLabel;
	legacy_version_information.supported_versions.push_back(kFakeVersionLabel);
	legacy_version_information.supported_versions.push_back(kFakeVersionLabel2);
	return legacy_version_information;
	}

	TransportParameters::VersionInformation CreateFakeVersionInformation() {
	TransportParameters::VersionInformation version_information;
	version_information.chosen_version = kFakeVersionLabel;
	version_information.other_versions.push_back(kFakeVersionLabel);
	return version_information;
	}

	// Make a TransportParameters that has a few fields set to help test comparison.
	std::unique_ptr<TransportParameters> MakeFakeTransportParams() {
	auto params = std::make_unique<TransportParameters>();
	params->perspective = Perspective::IS_CLIENT;
	params->legacy_version_information = CreateFakeLegacyVersionInformation();
	params->version_information = CreateFakeVersionInformation();
	params->max_idle_timeout_ms.set_value(kFakeIdleTimeoutMilliseconds);
	params->stateless_reset_token = CreateFakeStatelessResetToken();
	params->max_udp_payload_size.set_value(kFakeMaxPacketSize);
	params->initial_max_data.set_value(kFakeInitialMaxData);
	params->disable_active_migration = kFakeDisableMigration;
	params->custom_parameters[kCustomParameter1] = kCustomParameter1Value;
	params->custom_parameters[kCustomParameter2] = kCustomParameter2Value;
	return params;
	}

	// Generated by running TlsClientHandshakerTest.ZeroRttResumption and in
	// TlsClientHandshaker::InsertSession calling SSL_SESSION_to_bytes to serialize
	// the received 0-RTT capable ticket.
	static const char kCachedSession[] =
	"30820ad7020101020203040402130104206594ce84e61a866b56163c4ba09079aebf1d4f"
	"6cbcbd38dc9d7066a38a76c9cf0420ec9062063582a4cc0a44f9ff93256a195153ba6032"
	"0cf3c9189990932d838adaa10602046196f7b9a205020302a300a382039f3082039b3082"
	"0183a00302010202021001300d06092a864886f70d010105050030623111300f06035504"
	"030c08426f677573204941310b300906035504080c024d41310b30090603550406130255"
	"533121301f06092a864886f70d0109011612626f67757340626f6775732d69612e636f6d"
	"3110300e060355040a0c07426f6775734941301e170d3231303132383136323030315a17"
	"0d3331303132363136323030315a3069311d301b06035504030c14746573745f6563632e"
	"6578616d706c652e636f6d310b300906035504080c024d41310b30090603550406130255"
	"53311e301c06092a864886f70d010901160f626f67757340626f6775732e636f6d310e30"
	"0c060355040a0c05426f6775733059301306072a8648ce3d020106082a8648ce3d030107"
	"034200041ba5e2b6f24e64990b9f24ae6d23473d8c77fbcfb7f554f36559529a69a57170"
	"a10a81b7fe4a36ebf37b0a8c5e467a8443d8b8c002892aa5c1194bd843f42c9aa31f301d"
	"301b0603551d11041430128210746573742e6578616d706c652e636f6d300d06092a8648"
	"86f70d0101050500038202010019921d54ac06948763d609215f64f5d6540e3da886c6c9"
	"61bc737a437719b4621416ef1229f39282d7d3234e1a5d57535473066233bd246eec8e96"
	"1e0633cf4fe014c800e62599981820ec33d92e74ded0fa2953db1d81e19cb6890b6305b6"
	"3ede8d3e9fcf3c09f3f57283acf08aa57be4ee9a68d00bb3e2ded5920c619b5d83e5194a"
	"adb77ae5d61ed3e0a5670f0ae61cc3197329f0e71e3364dcab0405e9e4a6646adef8f022"
	"6415ec16c8046307b1769029fe780bd576114dde2fa9b4a32aa70bc436549a24ee4907a9"
	"045f6457ce8dfd8d62cc65315afe798ae1a948eefd70b035d415e73569c48fb20085de1a"
	"87de039e6b0b9a5fcb4069df27f3a7a1409e72d1ac739c72f29ef786134207e61c79855f"
	"c22e3ee5f6ad59a7b1ff0f18d79776f1c95efaebbebe381664132a58a1e7ff689945b7e0"
	"88634b0872feeefbf6be020884b994c6a7ff435f2b3f609077ff97cb509cfa17ff479b34"
	"e633e4b5bc46b20c5f27c80a2e2943f795a928acd5a3fc43c3af8425ad600c048b41d87e"
	"6361bc72fc4e5e44680a3d325674ba6ffa760d2fc7d9e4847a8e0dd9d35a543324e18b94"
	"2d42af6391ed1dd54a39e3f4a4c6b32486eb4ba72815dbd89c56fc053743a0b0483ce676"
	"15defce6800c629b99d0cbc56da162487f475b7c246099eaf1e6d10a022b2f49c6af1da3"
	"e8ed66096f267c4a76976b9572db7456ef90278330a4020400aa81b60481b3494e534543"
	"55524500f3439e548c21d2ad6e5634cc1cc0045730819702010102020304040213010400"
	"0420ec9062063582a4cc0a44f9ff93256a195153ba60320cf3c9189990932d838adaa106"
	"02046196f7b9a205020302a300a4020400b20302011db5060404130800cdb807020500ff"
	"ffffffb9050203093a80ba0404026833bb030101ffbc23042100d27d985bfce04833f02d"
	"38366b219f4def42bc4ba1b01844d1778db11731487dbd020400be020400b20302011db3"
	"8205da308205d6308203bea00302010202021000300d06092a864886f70d010105050030"
	"62310b3009060355040613025553310b300906035504080c024d413110300e060355040a"
	"0c07426f67757343413111300f06035504030c08426f6775732043413121301f06092a86"
	"4886f70d0109011612626f67757340626f6775732d63612e636f6d3020170d3231303132"
	"383136313935385a180f32303730303531313136313935385a30623111300f0603550403"
	"0c08426f677573204941310b300906035504080c024d41310b3009060355040613025553"
	"3121301f06092a864886f70d0109011612626f67757340626f6775732d69612e636f6d31"
	"10300e060355040a0c07426f677573494130820222300d06092a864886f70d0101010500"
	"0382020f003082020a028202010096c03a0ffc61bcedcd5ec9bf6f848b8a066b43f08377"
	"3af518a6a0044f22e666e24d2ae741954e344302c4be04612185bd53bcd848eb322bf900"
	"724eb0848047d647033ffbddb00f01d1de7c1cdb684f83c9bf5fd18ff60afad5a53b0d7d"
	"2c2a50abc38df019cd7f50194d05bc4597a1ef8570ea04069a2c36d74496af126573ca18"
	"8e470009b56250fadf2a04e837ee3837b36b1f08b7a0cfe2533d05f26484ce4e30203d01"
	"517fffd3da63d0341079ddce16e9ab4dbf9d4049e5cc52326031e645dd682fe6220d9e0e"
	"95451f5a82f3e1720dc13e8499466426a0bdbea9f6a76b3c9228dd3c79ab4dcc4c145ef0"
	"e78d1ee8bfd4650692d7e28a54bed809d8f7b37fe24c586be59cc46638531cb291c8c156"
	"8f08d67e768e51563e95a639c1f138b275ffad6a6a2a042ba9e26ad63c2ce63b600013f0"
	"a6f0703ee51c4f457f7bab0391c2fc4c5bb3213742c9cf9941bff68cc2e1cc96139d35ed"
	"1885244ddde0bf658416c486701841b81f7b17503d08c59a4db08a2a80755e007aa3b6c7"
	"eadcaa9e07c8325f3689f100de23970b12c9d9f6d0a8fb35ba0fd75c64410318db4a13ac"
	"3972ad16cdf6408af37013c7bcd7c42f20d6d04c3e39436c7531e8dafa219dd04b784ef0"
	"3c70ee5a4782b33cafa925aa3deca62a14aed704f179b932efabc2b0c5c15a8a99bfc9e6"
	"189dce7da50ea303594b6af9c933dd54b6e9d17c472d0203010001a38193308190300f06"
	"03551d130101ff040530030101ff301d0603551d0e041604141a98e80029a80992b7e5e0"
	"068ab9b3486cd839d6301f0603551d23041830168014780beeefe2fa419c48a438bdb30b"
	"e37ef0b7a94e300b0603551d0f0404030202a430130603551d25040c300a06082b060105"
	"05070301301b0603551d11041430128207426f67757343418207426f6775734941300d06"
	"092a864886f70d010105050003820201009e822ed8064b1aabaddf1340010ea147f68c06"
	"5a5a599ea305349f1b0e545a00817d6e55c7bf85560fab429ca72186c4d520b52f5cc121"
	"abd068b06f3111494431d2522efa54642f907059e7db80b73bb5ecf621377195b8700bba"
	"df798cece8c67a9571548d0e6592e81ae5d934877cb170aef18d3b97f635600fe0890d98"
	"f88b33fe3d1fd34c1c915beae4e5c0b133f476c40b21d220f16ce9cdd9e8f97a36a31723"
	"68875f052c9271648d9cb54687c6fdc3ea96f2908003bc5e5e79de00a21da7b8429f8b08"
	"af4c4d34641e386d72eabf5f01f106363f2ffd18969bf0bb9a4d17627c6427ff772c4308"
	"83c276feef5fc6dba9582c22fdbe9df7e8dfca375695f028ed588df54f3c86462dbf4c07"
	"91d80ca738988a1419c86bb4dd8d738b746921f01f39422e5ffd488b6f00195b996e6392"
	"3a820a32cd78b5989f339c0fcf4f269103964a30a16347d0ffdc8df1f3653ddc1515fa09"
	"22c7aef1af1fbcb23e93ae7622ab1ee11fcfa98319bad4c37c091cad46bd0337b3cc78b5"
	"5b9f1ea7994acc1f89c49a0b4cb540d2137e266fd43e56a9b5b778217b6f77df530e1eaf"
	"b3417262b5ddb86d3c6c5ac51e3f326c650dcc2434473973b7182c66220d1f3871bde7ee"
	"47d3f359d3d4c5bdd61baa684c03db4c75f9d6690c9e6e3abe6eaf5fa2c33c4daf26b373"
	"d85a1e8a7d671ac4a0a97b14e36e81280de4593bbb12da7695b5060404130800cdb60301"
	"0100b70402020403b807020500ffffffffb9050203093a80ba0404026833bb030101ffbd"
	"020400be020400";

	class QuicClientSessionCacheTest : public QuicTest {
	public:
	QuicClientSessionCacheTest() : ssl_ctx_(SSL_CTX_new(TLS_method())) {
	clock_.AdvanceTime(QuicTime::Delta::FromSeconds(1));
	}

	protected:
	bssl::UniquePtr<SSL_SESSION> NewSSLSession() {
	std::string cached_session =
	absl::HexStringToBytes(absl::string_view(kCachedSession));
	SSL_SESSION* session = SSL_SESSION_from_bytes(
	reinterpret_cast<const uint8_t*>(cached_session.data()),
	cached_session.size(), ssl_ctx_.get());
	QUICHE_DCHECK(session);
	return bssl::UniquePtr<SSL_SESSION>(session);
	}

	bssl::UniquePtr<SSL_SESSION> MakeTestSession(
	QuicTime::Delta timeout = kTimeout) {
	bssl::UniquePtr<SSL_SESSION> session = NewSSLSession();
	SSL_SESSION_set_time(session.get(), clock_.WallNow().ToUNIXSeconds());
	SSL_SESSION_set_timeout(session.get(), timeout.ToSeconds());
	return session;
	}

	bssl::UniquePtr<SSL_CTX> ssl_ctx_;
	MockClock clock_;
	};

	// Tests that simple insertion and lookup work correctly.
	TEST_F(QuicClientSessionCacheTest, SingleSession) {
	QuicClientSessionCache cache;

	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	QuicServerId id1("a.com", 443);

	auto params2 = MakeFakeTransportParams();
	auto session2 = MakeTestSession();
	SSL_SESSION* unowned2 = session2.get();
	QuicServerId id2("b.com", 443);

	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	EXPECT_EQ(nullptr, cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get()));
	EXPECT_EQ(0u, cache.size());

	cache.Insert(id1, std::move(session), *params, nullptr);
	EXPECT_EQ(1u, cache.size());
	EXPECT_EQ(
	*params,
	*(cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get())->transport_params));
	EXPECT_EQ(nullptr, cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get()));
	// No session is available for id1, even though the entry exists.
	EXPECT_EQ(1u, cache.size());
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	// Lookup() will trigger a deletion of invalid entry.
	EXPECT_EQ(0u, cache.size());

	auto session3 = MakeTestSession();
	SSL_SESSION* unowned3 = session3.get();
	QuicServerId id3("c.com", 443);
	cache.Insert(id3, std::move(session3), *params, nullptr);
	cache.Insert(id2, std::move(session2), *params2, nullptr);
	EXPECT_EQ(2u, cache.size());
	EXPECT_EQ(
	unowned2,
	cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
	EXPECT_EQ(
	unowned3,
	cache.Lookup(id3, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());

	// Verify that the cache is cleared after Lookups.
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	EXPECT_EQ(nullptr, cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get()));
	EXPECT_EQ(nullptr, cache.Lookup(id3, clock_.WallNow(), ssl_ctx_.get()));
	EXPECT_EQ(0u, cache.size());
	}

	TEST_F(QuicClientSessionCacheTest, MultipleSessions) {
	QuicClientSessionCache cache;

	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	QuicServerId id1("a.com", 443);
	auto session2 = MakeTestSession();
	SSL_SESSION* unowned2 = session2.get();
	auto session3 = MakeTestSession();
	SSL_SESSION* unowned3 = session3.get();

	cache.Insert(id1, std::move(session), *params, nullptr);
	cache.Insert(id1, std::move(session2), *params, nullptr);
	cache.Insert(id1, std::move(session3), *params, nullptr);
	// The latest session is popped first.
	EXPECT_EQ(
	unowned3,
	cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
	EXPECT_EQ(
	unowned2,
	cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
	// Only two sessions are cached.
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	}

	// Test that when a different TransportParameter is inserted for
	// the same server id, the existing entry is removed.
	TEST_F(QuicClientSessionCacheTest, DifferentTransportParams) {
	QuicClientSessionCache cache;

	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	QuicServerId id1("a.com", 443);
	auto session2 = MakeTestSession();
	auto session3 = MakeTestSession();
	SSL_SESSION* unowned3 = session3.get();

	cache.Insert(id1, std::move(session), *params, nullptr);
	cache.Insert(id1, std::move(session2), *params, nullptr);
	// tweak the transport parameters a little bit.
	params->perspective = Perspective::IS_SERVER;
	cache.Insert(id1, std::move(session3), *params, nullptr);
	auto resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
	EXPECT_EQ(unowned3, resumption_state->tls_session.get());
	EXPECT_EQ(params.get(), resumption_state->transport_params);
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	}

	TEST_F(QuicClientSessionCacheTest, DifferentApplicationState) {
	QuicClientSessionCache cache;

	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	QuicServerId id1("a.com", 443);
	auto session2 = MakeTestSession();
	auto session3 = MakeTestSession();
	SSL_SESSION* unowned3 = session3.get();
	ApplicationState state;
	state.push_back('a');

	cache.Insert(id1, std::move(session), *params, &state);
	cache.Insert(id1, std::move(session2), *params, &state);
	cache.Insert(id1, std::move(session3), *params, nullptr);
	auto resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
	EXPECT_EQ(unowned3, resumption_state->tls_session.get());
	EXPECT_EQ(nullptr, resumption_state->application_state);
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	}

	TEST_F(QuicClientSessionCacheTest, BothStatesDifferent) {
	QuicClientSessionCache cache;

	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	QuicServerId id1("a.com", 443);
	auto session2 = MakeTestSession();
	auto session3 = MakeTestSession();
	SSL_SESSION* unowned3 = session3.get();
	ApplicationState state;
	state.push_back('a');

	cache.Insert(id1, std::move(session), *params, &state);
	cache.Insert(id1, std::move(session2), *params, &state);
	params->perspective = Perspective::IS_SERVER;
	cache.Insert(id1, std::move(session3), *params, nullptr);
	auto resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
	EXPECT_EQ(unowned3, resumption_state->tls_session.get());
	EXPECT_EQ(params.get(), resumption_state->transport_params);
	EXPECT_EQ(nullptr, resumption_state->application_state);
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	}

	// When the size limit is exceeded, the oldest entry should be erased.
	TEST_F(QuicClientSessionCacheTest, SizeLimit) {
	QuicClientSessionCache cache(2);

	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	QuicServerId id1("a.com", 443);

	auto session2 = MakeTestSession();
	SSL_SESSION* unowned2 = session2.get();
	QuicServerId id2("b.com", 443);

	auto session3 = MakeTestSession();
	SSL_SESSION* unowned3 = session3.get();
	QuicServerId id3("c.com", 443);

	cache.Insert(id1, std::move(session), *params, nullptr);
	cache.Insert(id2, std::move(session2), *params, nullptr);
	cache.Insert(id3, std::move(session3), *params, nullptr);

	EXPECT_EQ(2u, cache.size());
	EXPECT_EQ(
	unowned2,
	cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
	EXPECT_EQ(
	unowned3,
	cache.Lookup(id3, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	}

	TEST_F(QuicClientSessionCacheTest, ClearEarlyData) {
	QuicClientSessionCache cache;
	SSL_CTX_set_early_data_enabled(ssl_ctx_.get(), 1);
	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	QuicServerId id1("a.com", 443);
	auto session2 = MakeTestSession();

	EXPECT_TRUE(SSL_SESSION_early_data_capable(session.get()));
	EXPECT_TRUE(SSL_SESSION_early_data_capable(session2.get()));

	cache.Insert(id1, std::move(session), *params, nullptr);
	cache.Insert(id1, std::move(session2), *params, nullptr);

	cache.ClearEarlyData(id1);

	auto resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
	EXPECT_FALSE(
	SSL_SESSION_early_data_capable(resumption_state->tls_session.get()));
	resumption_state = cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get());
	EXPECT_FALSE(
	SSL_SESSION_early_data_capable(resumption_state->tls_session.get()));
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	}

	// Expired session isn't considered valid and nullptr will be returned upon
	// Lookup.
	TEST_F(QuicClientSessionCacheTest, Expiration) {
	QuicClientSessionCache cache;

	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	QuicServerId id1("a.com", 443);

	auto session2 = MakeTestSession(3 * kTimeout);
	SSL_SESSION* unowned2 = session2.get();
	QuicServerId id2("b.com", 443);

	cache.Insert(id1, std::move(session), *params, nullptr);
	cache.Insert(id2, std::move(session2), *params, nullptr);

	EXPECT_EQ(2u, cache.size());
	// Expire the session.
	clock_.AdvanceTime(kTimeout * 2);
	// The entry has not been removed yet.
	EXPECT_EQ(2u, cache.size());

	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	EXPECT_EQ(1u, cache.size());
	EXPECT_EQ(
	unowned2,
	cache.Lookup(id2, clock_.WallNow(), ssl_ctx_.get())->tls_session.get());
	EXPECT_EQ(1u, cache.size());
	}

	TEST_F(QuicClientSessionCacheTest, RemoveExpiredEntriesAndClear) {
	QuicClientSessionCache cache;

	auto params = MakeFakeTransportParams();
	auto session = MakeTestSession();
	quic::QuicServerId id1("a.com", 443);

	auto session2 = MakeTestSession(3 * kTimeout);
	quic::QuicServerId id2("b.com", 443);

	cache.Insert(id1, std::move(session), *params, nullptr);
	cache.Insert(id2, std::move(session2), *params, nullptr);

	EXPECT_EQ(2u, cache.size());
	// Expire the session.
	clock_.AdvanceTime(kTimeout * 2);
	// The entry has not been removed yet.
	EXPECT_EQ(2u, cache.size());

	// Flush expired sessions.
	cache.RemoveExpiredEntries(clock_.WallNow());

	// session is expired and should be flushed.
	EXPECT_EQ(nullptr, cache.Lookup(id1, clock_.WallNow(), ssl_ctx_.get()));
	EXPECT_EQ(1u, cache.size());

	cache.Clear();
	EXPECT_EQ(0u, cache.size());
	}

	} // namespace
	} // namespace test
	} // namespace quic