implement receiving of DATAGRAM frames

internal/mocks/quic/early_session.go

@@ -197,6 +197,21 @@ func (mr *MockEarlySessionMockRecorder) OpenUniStreamSync(arg0 interface{}) *gom
 	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "OpenUniStreamSync", reflect.TypeOf((*MockEarlySession)(nil).OpenUniStreamSync), arg0)
 }
 
+// ReceiveMessage mocks base method
+func (m *MockEarlySession) ReceiveMessage() ([]byte, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "ReceiveMessage")
+	ret0, _ := ret[0].([]byte)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// ReceiveMessage indicates an expected call of ReceiveMessage
+func (mr *MockEarlySessionMockRecorder) ReceiveMessage() *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ReceiveMessage", reflect.TypeOf((*MockEarlySession)(nil).ReceiveMessage))
+}
+
 // RemoteAddr mocks base method
 func (m *MockEarlySession) RemoteAddr() net.Addr {
 	m.ctrl.T.Helper()

internal/protocol/params.go

@@ -130,6 +130,10 @@ const MaxAckFrameSize ByteCount = 1000
 // The size is chosen such that a DATAGRAM frame fits into a QUIC packet.
 const MaxDatagramFrameSize ByteCount = 1200
 
+// DatagramRcvQueueLen is the length of the receive queue for DATAGRAM frames.
+// See https://datatracker.ietf.org/doc/draft-pauly-quic-datagram/.
+const DatagramRcvQueueLen = 128
+
 // MaxNumAckRanges is the maximum number of ACK ranges that we send in an ACK frame.
 // It also serves as a limit for the packet history.
 // If at any point we keep track of more ranges, old ranges are discarded.