add a 0-RTT encryption level

internal/protocol/encryption_level.go

@@ -11,6 +11,8 @@ const (
 	EncryptionInitial
 	// EncryptionHandshake is the Handshake encryption level
 	EncryptionHandshake
+	// Encryption0RTT is the 0-RTT encryption level
+	Encryption0RTT
 	// Encryption1RTT is the 1-RTT encryption level
 	Encryption1RTT
 )
@@ -21,6 +23,8 @@ func (e EncryptionLevel) String() string {
 		return "Initial"
 	case EncryptionHandshake:
 		return "Handshake"
+	case Encryption0RTT:
+		return "0-RTT"
 	case Encryption1RTT:
 		return "1-RTT"
 	}

internal/protocol/encryption_level_test.go

@@ -10,6 +10,7 @@ var _ = Describe("Encryption Level", func() {
 		Expect(EncryptionUnspecified.String()).To(Equal("unknown"))
 		Expect(EncryptionInitial.String()).To(Equal("Initial"))
 		Expect(EncryptionHandshake.String()).To(Equal("Handshake"))
+		Expect(Encryption0RTT.String()).To(Equal("0-RTT"))
 		Expect(Encryption1RTT.String()).To(Equal("1-RTT"))
 	})
 })