Add WT_ENABLED setting

Summary:
Adding new WT_ENABLED setting from H3 WebTransport draft 15:
> When an HTTP/3 connection is established, the server sends a SETTINGS_WT_ENABLED setting to indicate support for WebTransport over HTTP/3.

Reviewed By: hanidamlaj

Differential Revision: D100703616

fbshipit-source-id: 1cbf5ea427e74be956078c94de1e2d169b759fda

Author: Joanna Jo

proxygen/lib/http/codec/H3EarlyDataHandler.cpp

@@ -51,6 +51,7 @@ bool isLimitSetting(hq::SettingId id) {
     case hq::SettingId::H3_DATAGRAM_DRAFT_8:
     case hq::SettingId::H3_DATAGRAM_RFC:
     case hq::SettingId::ENABLE_WEBTRANSPORT:
+    case hq::SettingId::WT_ENABLED:
       return false;
   }
   // Unknown settings are treated as limits

proxygen/lib/http/codec/HQControlCodec.cpp

@@ -105,6 +105,7 @@ ParseResult HQControlCodec::parseSettings(Cursor& cursor,
       case hq::SettingId::H3_DATAGRAM_DRAFT_8:
       case hq::SettingId::H3_DATAGRAM_RFC:
       case hq::SettingId::ENABLE_WEBTRANSPORT:
+      case hq::SettingId::WT_ENABLED:
         // only 0/1 are legal
         if (setting.second > 1) {
           return HTTP3::ErrorCode::HTTP_SETTINGS_ERROR;
@@ -234,6 +235,7 @@ size_t HQControlCodec::generateSettings(folly::IOBufQueue& writeBuf) {
         case hq::SettingId::ENABLE_WEBTRANSPORT:
         case hq::SettingId::H3_WT_MAX_SESSIONS:
         case hq::SettingId::WT_INITIAL_MAX_DATA:
+        case hq::SettingId::WT_ENABLED:
           break;
       }
       settings.emplace_back(*id, (SettingValue)setting.value);

proxygen/lib/http/codec/HQFramer.cpp

@@ -101,6 +101,7 @@ decodeSettingValue(folly::io::Cursor& cursor,
     case SettingId::ENABLE_WEBTRANSPORT:
     case SettingId::H3_WT_MAX_SESSIONS:
     case SettingId::WT_INITIAL_MAX_DATA:
+    case SettingId::WT_ENABLED:
       return value;
   }
   return folly::none;

proxygen/lib/http/codec/HQFramer.h

@@ -103,6 +103,7 @@ enum class SettingId : uint64_t {
   ENABLE_WEBTRANSPORT = 0x2b603742,
   H3_WT_MAX_SESSIONS = 0x14e9cd29,
   WT_INITIAL_MAX_DATA = 0x2b61,
+  WT_ENABLED = 0x2c7cf000,
 };
 
 using SettingValue = uint64_t;

proxygen/lib/http/codec/HQUtils.cpp

@@ -99,6 +99,8 @@ folly::Optional<hq::SettingId> httpToHqSettingsId(proxygen::SettingsId id) {
       return hq::SettingId::H3_WT_MAX_SESSIONS;
     case proxygen::SettingsId::WT_INITIAL_MAX_DATA:
       return hq::SettingId::WT_INITIAL_MAX_DATA;
+    case proxygen::SettingsId::WT_ENABLED:
+      return hq::SettingId::WT_ENABLED;
     default:
       return folly::none; // this setting has no meaning in HQ
   }
@@ -126,6 +128,8 @@ folly::Optional<proxygen::SettingsId> hqToHttpSettingsId(hq::SettingId id) {
       return proxygen::SettingsId::H3_WT_MAX_SESSIONS;
     case hq::SettingId::WT_INITIAL_MAX_DATA:
       return proxygen::SettingsId::WT_INITIAL_MAX_DATA;
+    case hq::SettingId::WT_ENABLED:
+      return proxygen::SettingsId::WT_ENABLED;
   }
   return folly::none;
 }

proxygen/lib/http/codec/SettingsId.h

@@ -51,6 +51,7 @@ enum class SettingsId : uint64_t {
   _HQ_DATAGRAM_RFC = HQ_SETTINGS_MASK | 0x33,
   ENABLE_WEBTRANSPORT = 0x2b603742,
   H3_WT_MAX_SESSIONS = 0x14e9cd29,
+  WT_ENABLED = 0x2c7cf000,
 };
 
 using SettingPair = std::pair<SettingsId, uint32_t>;

proxygen/lib/http/coro/HTTPCoroSession.cpp

@@ -775,6 +775,7 @@ void HTTPQuicCoroSession::applyEgressSettings() {
         case hq::SettingId::ENABLE_WEBTRANSPORT:
         case hq::SettingId::H3_WT_MAX_SESSIONS:
         case hq::SettingId::WT_INITIAL_MAX_DATA:
+        case hq::SettingId::WT_ENABLED:
           // TODO
           break;
       }
@@ -1608,6 +1609,7 @@ void HTTPQuicCoroSession::onSettings(const SettingsList& settings) {
         case hq::SettingId::ENABLE_WEBTRANSPORT:
         case hq::SettingId::H3_WT_MAX_SESSIONS:
         case hq::SettingId::WT_INITIAL_MAX_DATA:
+        case hq::SettingId::WT_ENABLED:
           // TODO
           break;
       }

proxygen/lib/http/session/HQSession.cpp

@@ -804,6 +804,7 @@ size_t HQSession::sendSettings() {
         case hq::SettingId::H3_DATAGRAM_RFC:
         case hq::SettingId::H3_WT_MAX_SESSIONS:
         case hq::SettingId::WT_INITIAL_MAX_DATA:
+        case hq::SettingId::WT_ENABLED:
           break;
         case hq::SettingId::ENABLE_WEBTRANSPORT:
           if (setting.value) {
@@ -1585,6 +1586,11 @@ void HQSession::applySettings(const SettingsList& settings) {
           VLOG(3) << "Peer sent WT_INITIAL_MAX_DATA=" << setting.value;
           wtInitialSendWindow_ = setting.value;
           break;
+        case hq::SettingId::WT_ENABLED:
+          // TODO: This part of the code needs a larger refactor. We shouldn't
+          // be setting supportsWebTransport_ unless: 1) WT_ENABLED =
+          // ENABLE_CONNECT_PROTOCOL = H3_DATAGRAM == 1 or 2) H3_DATAGRAM == 1
+          break;
       }
     }
   }