Default-enable IETF QUIC h3-29

This CL changes the default list of supported versions to both
Q050 and h3-29. This means that users of Chrome that do not use
Finch will now have support for h3-29, and also that cronet users
also get support for it. Note that this is disabled for cronet users
that use connection migration, as we are not yet spec-compliant there.

This CL also default-disabled 0-RTT for QUIC+TLS because we haven't
yet launched it via Finch.

R=renjietang@chromium.org

Change-Id: Ic547396c55e26136468c73d3c35b60ec2066f196
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2702157
Commit-Queue: David Schinazi <dschinazi@chromium.org>
Auto-Submit: David Schinazi <dschinazi@chromium.org>
Reviewed-by: Renjie Tang <renjietang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#855084}

components/cronet/url_request_context_config.cc

@@ -553,6 +553,27 @@ void URLRequestContextConfig::ParseAndSetExperimentalOptions(
         quic_params->ios_network_service_type = quic_ios_network_service_type;
       }
 
+      // Do not enable IETF QUIC when connection migration is enabled because
+      // our current connection migration code does not yet fully support the
+      // version of connection migration in the IETF spec.
+      // TODO(dschinazi) remove this once we support the spec.
+      if ((quic_migrate_sessions_on_network_change_v2 ||
+           quic_migrate_idle_sessions || quic_migrate_sessions_early_v2) &&
+          quic_version_string.empty()) {
+        quic::ParsedQuicVersionVector migration_versions;
+        for (const quic::ParsedQuicVersion& version :
+             quic_params->supported_versions) {
+          if (!version.UsesHttp3()) {
+            migration_versions.push_back(version);
+          }
+        }
+        quic_params->supported_versions = migration_versions;
+        if (quic_params->supported_versions.empty()) {
+          quic_params->supported_versions =
+              quic::ParsedQuicVersionVector{quic::ParsedQuicVersion::Q050()};
+        }
+      }
+
     } else if (it.key() == kAsyncDnsFieldTrialName) {
       const base::DictionaryValue* async_dns_args = nullptr;
       if (!it.value().GetAsDictionary(&async_dns_args)) {

components/cronet/url_request_context_config_unittest.cc

@@ -862,6 +862,8 @@ TEST(URLRequestContextConfigTest, SetQuicConnectionMigrationV2Options) {
             quic_params->max_migrations_to_non_default_network_on_write_error);
   EXPECT_EQ(
       4, quic_params->max_migrations_to_non_default_network_on_path_degrading);
+  EXPECT_EQ(quic::ParsedQuicVersionVector{quic::ParsedQuicVersion::Q050()},
+            quic_params->supported_versions);
 }
 
 TEST(URLRequestContextConfigTest, SetQuicStaleDNSracing) {

net/http/http_server_properties_manager_unittest.cc

@@ -1527,7 +1527,7 @@ TEST_F(HttpServerPropertiesManagerTest, PersistAdvertisedVersionsToPref) {
       "\"isolation\":[],"
       "\"server\":\"https://www.google.com:80\"},"
       "{\"alternative_service\":[{"
-      "\"advertised_versions\":[50],\"expiration\":\"9223372036854775807\","
+      "\"advertised_versions\":[50,73],\"expiration\":\"9223372036854775807\","
       "\"host\":\"foo.google.com\",\"port\":444,\"protocol_str\":\"quic\"}],"
       "\"isolation\":[],"
       "\"network_stats\":{\"srtt\":42},"
@@ -1638,7 +1638,7 @@ TEST_F(HttpServerPropertiesManagerTest,
       "\"server_id\":\"https://mail.google.com:80\","
       "\"server_info\":\"quic_server_info1\"}],"
       "\"servers\":["
-      "{\"alternative_service\":[{\"advertised_versions\":[50],"
+      "{\"alternative_service\":[{\"advertised_versions\":[50,73],"
       "\"expiration\":\"13756212000000000\",\"port\":443,"
       "\"protocol_str\":\"quic\"}],"
       "\"isolation\":[],"

net/quic/quic_context.h

@@ -16,7 +16,15 @@ namespace net {
 // configuration.
 inline NET_EXPORT_PRIVATE quic::ParsedQuicVersionVector
 DefaultSupportedQuicVersions() {
-  return quic::ParsedQuicVersionVector{quic::ParsedQuicVersion::Q050()};
+  // The ordering of this list does not matter for Chrome because it respects
+  // the ordering received from the server via Alt-Svc. However, cronet offers
+  // an addQuicHint() API which uses the first version from this list until
+  // it receives Alt-Svc from the server. We therefore list Q050 first here
+  // because there are some cronet applications which communicate with servers
+  // that speak Q050 but not Draft29.
+  // TODO(dschinazi) Move Draft29 first once those servers support it.
+  return quic::ParsedQuicVersionVector{quic::ParsedQuicVersion::Q050(),
+                                       quic::ParsedQuicVersion::Draft29()};
 }
 
 // Obsolete QUIC supported versions are versions that are supported by the
@@ -171,7 +179,7 @@ struct NET_EXPORT QuicParams {
   // smoothed rtt is present.
   base::TimeDelta initial_rtt_for_handshake;
   // If true, QUIC with TLS will not try 0-RTT connection.
-  bool disable_tls_zero_rtt = false;
+  bool disable_tls_zero_rtt = true;
   // If true, gQUIC requests will always require confirmation.
   bool disable_gquic_zero_rtt = false;
   // Network Service Type of the socket for iOS. Default is NET_SERVICE_TYPE_BE