3 files changed, 6 insertions, 15 deletions
diff --git a/pkg/tcpip/network/ipv6/icmp.go b/pkg/tcpip/network/ipv6/icmp.go
index 7b638e9d0..6c14b4aae 100644
--- a/pkg/tcpip/network/ipv6/icmp.go
+++ b/pkg/tcpip/network/ipv6/icmp.go
@@ -21,15 +21,6 @@ import (
 	"gvisor.dev/gvisor/pkg/tcpip/stack"
 )
 
-const (
-	// ndpHopLimit is the expected IP hop limit value of 255 for received
-	// NDP packets, as per RFC 4861 sections 4.1 - 4.5, 6.1.1, 6.1.2, 7.1.1,
-	// 7.1.2 and 8.1. If the hop limit value is not 255, nodes MUST silently
-	// drop the NDP packet. All outgoing NDP packets must use this value for
-	// its IP hop limit field.
-	ndpHopLimit = 255
-)
-
 // handleControl handles the case when an ICMP packet contains the headers of
 // the original packet that caused the ICMP one to be sent. This information is
 // used to find out which transport endpoint must be notified about the ICMP
@@ -90,7 +81,7 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V
 		header.ICMPv6RouterSolicit,
 		header.ICMPv6RouterAdvert,
 		header.ICMPv6RedirectMsg:
-		if iph.HopLimit() != ndpHopLimit {
+		if iph.HopLimit() != header.NDPHopLimit {
 			received.Invalid.Increment()
 			return
 		}
@@ -217,7 +208,7 @@ func (e *endpoint) handleICMP(r *stack.Route, netHeader buffer.View, vv buffer.V
 		//
 		// The IP Hop Limit field has a value of 255, i.e., the packet
 		// could not possibly have been forwarded by a router.
-		if err := r.WritePacket(nil /* gso */, hdr, buffer.VectorisedView{}, stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: ndpHopLimit, TOS: stack.DefaultTOS}); err != nil {
+		if err := r.WritePacket(nil /* gso */, hdr, buffer.VectorisedView{}, stack.NetworkHeaderParams{Protocol: header.ICMPv6ProtocolNumber, TTL: header.NDPHopLimit, TOS: stack.DefaultTOS}); err != nil {
 			sent.Dropped.Increment()
 			return
 		}
@@ -359,7 +350,7 @@ func (*protocol) LinkAddressRequest(addr, localAddr tcpip.Address, linkEP stack.
 	ip.Encode(&header.IPv6Fields{
 		PayloadLength: length,
 		NextHeader:    uint8(header.ICMPv6ProtocolNumber),
-		HopLimit:      ndpHopLimit,
+		HopLimit:      header.NDPHopLimit,
 		SrcAddr:       r.LocalAddress,
 		DstAddr:       r.RemoteAddress,
 	})
diff --git a/pkg/tcpip/network/ipv6/icmp_test.go b/pkg/tcpip/network/ipv6/icmp_test.go
index dd3c4d7c4..7c11dde55 100644
--- a/pkg/tcpip/network/ipv6/icmp_test.go
+++ b/pkg/tcpip/network/ipv6/icmp_test.go
@@ -143,7 +143,7 @@ func TestICMPCounts(t *testing.T) {
 		ip.Encode(&header.IPv6Fields{
 			PayloadLength: uint16(payloadLength),
 			NextHeader:    uint8(header.ICMPv6ProtocolNumber),
-			HopLimit:      ndpHopLimit,
+			HopLimit:      header.NDPHopLimit,
 			SrcAddr:       r.LocalAddress,
 			DstAddr:       r.RemoteAddress,
 		})
diff --git a/pkg/tcpip/network/ipv6/ndp_test.go b/pkg/tcpip/network/ipv6/ndp_test.go
index e30791fe3..c32716f2e 100644
--- a/pkg/tcpip/network/ipv6/ndp_test.go
+++ b/pkg/tcpip/network/ipv6/ndp_test.go
@@ -150,7 +150,7 @@ func TestHopLimitValidation(t *testing.T) {
 
 			// Receive the NDP packet with an invalid hop limit
 			// value.
-			handleIPv6Payload(hdr, ndpHopLimit-1, ep, &r)
+			handleIPv6Payload(hdr, header.NDPHopLimit-1, ep, &r)
 
 			// Invalid count should have increased.
 			if got := invalid.Value(); got != 1 {
@@ -164,7 +164,7 @@ func TestHopLimitValidation(t *testing.T) {
 			}
 
 			// Receive the NDP packet with a valid hop limit value.
-			handleIPv6Payload(hdr, ndpHopLimit, ep, &r)
+			handleIPv6Payload(hdr, header.NDPHopLimit, ep, &r)
 
 			// Rx count of NDP packet of type typ.typ should have
 			// increased.