1 files changed, 32 insertions, 3 deletions
diff --git a/pkg/tcpip/header/ndp_options.go b/pkg/tcpip/header/ndp_options.go
index 1e60f3d4f..e6a6ad39b 100755
--- a/pkg/tcpip/header/ndp_options.go
+++ b/pkg/tcpip/header/ndp_options.go
@@ -17,6 +17,7 @@ package header
 import (
 	"encoding/binary"
 	"errors"
+	"fmt"
 	"math"
 	"time"
 
@@ -32,9 +33,9 @@ const (
 	// Address option, as per RFC 4861 section 4.6.1.
 	NDPTargetLinkLayerAddressOptionType = 2
 
-	// ndpLinkLayerAddressSize is the size of a Source or Target Link Layer
-	// Address option.
-	ndpLinkLayerAddressSize = 8
+	// NDPLinkLayerAddressSize is the size of a Source or Target Link Layer
+	// Address option for an Ethernet address.
+	NDPLinkLayerAddressSize = 8
 
 	// NDPPrefixInformationType is the type of the Prefix Information
 	// option, as per RFC 4861 section 4.6.2.
@@ -300,6 +301,8 @@ func (b NDPOptions) Serialize(s NDPOptionsSerializer) int {
 
 // NDPOption is the set of functions to be implemented by all NDP option types.
 type NDPOption interface {
+	fmt.Stringer
+
 	// Type returns the type of the receiver.
 	Type() uint8
 
@@ -397,6 +400,11 @@ func (o NDPSourceLinkLayerAddressOption) serializeInto(b []byte) int {
 	return copy(b, o)
 }
 
+// String implements fmt.Stringer.String.
+func (o NDPSourceLinkLayerAddressOption) String() string {
+	return fmt.Sprintf("%T(%s)", o, tcpip.LinkAddress(o))
+}
+
 // EthernetAddress will return an ethernet (MAC) address if the
 // NDPSourceLinkLayerAddressOption's body has at minimum EthernetAddressSize
 // bytes. If the body has more than EthernetAddressSize bytes, only the first
@@ -432,6 +440,11 @@ func (o NDPTargetLinkLayerAddressOption) serializeInto(b []byte) int {
 	return copy(b, o)
 }
 
+// String implements fmt.Stringer.String.
+func (o NDPTargetLinkLayerAddressOption) String() string {
+	return fmt.Sprintf("%T(%s)", o, tcpip.LinkAddress(o))
+}
+
 // EthernetAddress will return an ethernet (MAC) address if the
 // NDPTargetLinkLayerAddressOption's body has at minimum EthernetAddressSize
 // bytes. If the body has more than EthernetAddressSize bytes, only the first
@@ -478,6 +491,17 @@ func (o NDPPrefixInformation) serializeInto(b []byte) int {
 	return used
 }
 
+// String implements fmt.Stringer.String.
+func (o NDPPrefixInformation) String() string {
+	return fmt.Sprintf("%T(O=%t, A=%t, PL=%s, VL=%s, Prefix=%s)",
+		o,
+		o.OnLinkFlag(),
+		o.AutonomousAddressConfigurationFlag(),
+		o.PreferredLifetime(),
+		o.ValidLifetime(),
+		o.Subnet())
+}
+
 // PrefixLength returns the value in the number of leading bits in the Prefix
 // that are valid.
 //
@@ -587,6 +611,11 @@ func (o NDPRecursiveDNSServer) serializeInto(b []byte) int {
 	return used
 }
 
+// String implements fmt.Stringer.String.
+func (o NDPRecursiveDNSServer) String() string {
+	return fmt.Sprintf("%T(%s valid for %s)", o, o.Addresses(), o.Lifetime())
+}
+
 // Lifetime returns the length of time that the DNS server addresses
 // in this option may be used for name resolution.
 //