diff --git a/ipv4/gen.go b/ipv4/gen.go
index 9d490fa..1bb1737 100644
--- a/ipv4/gen.go
+++ b/ipv4/gen.go
@@ -80,7 +80,7 @@
 func geniana() error {
 	var bb bytes.Buffer
 	fmt.Fprintf(&bb, "// go generate gen.go\n")
-	fmt.Fprintf(&bb, "// GENERATED BY THE COMMAND ABOVE; DO NOT EDIT\n\n")
+	fmt.Fprintf(&bb, "// Code generated by the command above; DO NOT EDIT.\n\n")
 	fmt.Fprintf(&bb, "package ipv4\n\n")
 	for _, r := range registries {
 		resp, err := http.Get(r.url)
diff --git a/ipv4/iana.go b/ipv4/iana.go
index be10c94..4375b40 100644
--- a/ipv4/iana.go
+++ b/ipv4/iana.go
@@ -1,9 +1,9 @@
 // go generate gen.go
-// GENERATED BY THE COMMAND ABOVE; DO NOT EDIT
+// Code generated by the command above; DO NOT EDIT.
 
 package ipv4
 
-// Internet Control Message Protocol (ICMP) Parameters, Updated: 2013-04-19
+// Internet Control Message Protocol (ICMP) Parameters, Updated: 2018-02-26
 const (
 	ICMPTypeEchoReply              ICMPType = 0  // Echo Reply
 	ICMPTypeDestinationUnreachable ICMPType = 3  // Destination Unreachable
@@ -16,9 +16,11 @@
 	ICMPTypeTimestamp              ICMPType = 13 // Timestamp
 	ICMPTypeTimestampReply         ICMPType = 14 // Timestamp Reply
 	ICMPTypePhoturis               ICMPType = 40 // Photuris
+	ICMPTypeExtendedEchoRequest    ICMPType = 42 // Extended Echo Request
+	ICMPTypeExtendedEchoReply      ICMPType = 43 // Extended Echo Reply
 )
 
-// Internet Control Message Protocol (ICMP) Parameters, Updated: 2013-04-19
+// Internet Control Message Protocol (ICMP) Parameters, Updated: 2018-02-26
 var icmpTypes = map[ICMPType]string{
 	0:  "echo reply",
 	3:  "destination unreachable",
@@ -31,4 +33,6 @@
 	13: "timestamp",
 	14: "timestamp reply",
 	40: "photuris",
+	42: "extended echo request",
+	43: "extended echo reply",
 }