refactor: extract pdu statics into separate file

router/consts.go

@@ -6,8 +6,6 @@ import (
 )
 
 const (
-	Protocol           = "weave"
-	ProtocolVersion    = 10
 	EthernetOverhead   = 14
 	UDPOverhead        = 28 // 20 bytes for IPv4, 8 bytes for UDP
 	Port               = 6783
@@ -28,24 +26,7 @@ const (
 	MaxDuration        = time.Duration(math.MaxInt64)
 )
 
-const (
-	ProtocolConnectionEstablished = iota
-	ProtocolFragmentationReceived
-	ProtocolStartFragmentationTest
-	ProtocolNonce
-	ProtocolFetchAll
-	ProtocolUpdate
-	ProtocolPMTUVerified
-)
-
 var (
-	FragTest                           = make([]byte, FragTestSize)
-	PMTUDiscovery                      = make([]byte, PMTUDiscoverySize)
-	ProtocolConnectionEstablishedByte  = []byte{ProtocolConnectionEstablished}
-	ProtocolFragmentationReceivedByte  = []byte{ProtocolFragmentationReceived}
-	ProtocolStartFragmentationTestByte = []byte{ProtocolStartFragmentationTest}
-	ProtocolNonceByte                  = []byte{ProtocolNonce}
-	ProtocolFetchAllByte               = []byte{ProtocolFetchAll}
-	ProtocolUpdateByte                 = []byte{ProtocolUpdate}
-	ProtocolPMTUVerifiedByte           = []byte{ProtocolPMTUVerified}
+	FragTest      = make([]byte, FragTestSize)
+	PMTUDiscovery = make([]byte, PMTUDiscoverySize)
 )

router/protocol.go

@@ -0,0 +1,26 @@
+package router
+
+const (
+	Protocol        = "weave"
+	ProtocolVersion = 10
+)
+
+const (
+	ProtocolConnectionEstablished = iota
+	ProtocolFragmentationReceived
+	ProtocolStartFragmentationTest
+	ProtocolNonce
+	ProtocolFetchAll
+	ProtocolUpdate
+	ProtocolPMTUVerified
+)
+
+var (
+	ProtocolConnectionEstablishedByte  = []byte{ProtocolConnectionEstablished}
+	ProtocolFragmentationReceivedByte  = []byte{ProtocolFragmentationReceived}
+	ProtocolStartFragmentationTestByte = []byte{ProtocolStartFragmentationTest}
+	ProtocolNonceByte                  = []byte{ProtocolNonce}
+	ProtocolFetchAllByte               = []byte{ProtocolFetchAll}
+	ProtocolUpdateByte                 = []byte{ProtocolUpdate}
+	ProtocolPMTUVerifiedByte           = []byte{ProtocolPMTUVerified}
+)