1 files changed, 27 insertions, 3 deletions

diff --git a/pkg/tcpip/stack/nic.go b/pkg/tcpip/stack/nic.go
index e456e05f4..fe8f83d58 100644
--- a/pkg/tcpip/stack/nic.go
+++ b/pkg/tcpip/stack/nic.go
@@ -46,6 +46,10 @@ type NIC struct {
 
 	stats NICStats
 
+	// ndp is the NDP related state for NIC.
+	//
+	// Note, read and write operations on ndp require that the NIC is
+	// appropriately locked.
 	ndp ndpState
 }
 
@@ -80,10 +84,16 @@ const (
 	NeverPrimaryEndpoint
 )
 
+// newNIC returns a new NIC using the default NDP configurations from stack.
 func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, loopback bool) *NIC {
 	// TODO(b/141011931): Validate a LinkEndpoint (ep) is valid. For
 	// example, make sure that the link address it provides is a valid
 	// unicast ethernet address.
+
+	// TODO(b/143357959): RFC 8200 section 5 requires that IPv6 endpoints
+	// observe an MTU of at least 1280 bytes. Ensure that this requirement
+	// of IPv6 is supported on this endpoint's LinkEndpoint.
+
 	nic := &NIC{
 		stack:      stack,
 		id:         id,
@@ -105,9 +115,11 @@ func newNIC(stack *Stack, id tcpip.NICID, name string, ep LinkEndpoint, loopback
 			},
 		},
 		ndp: ndpState{
-			dad: make(map[tcpip.Address]dadState),
+			configs: stack.ndpConfigs,
+			dad:     make(map[tcpip.Address]dadState),
 		},
 	}
+	nic.ndp.nic = nic
 
 	// Register supported packet endpoint protocols.
 	for _, netProto := range header.Ethertypes {
@@ -432,7 +444,7 @@ func (n *NIC) addAddressLocked(protocolAddress tcpip.ProtocolAddress, peb Primar
 
 	// If we are adding a tentative IPv6 address, start DAD.
 	if isIPv6Unicast && kind == permanentTentative {
-		if err := n.ndp.startDuplicateAddressDetection(n, protocolAddress.AddressWithPrefix.Address, ref); err != nil {
+		if err := n.ndp.startDuplicateAddressDetection(protocolAddress.AddressWithPrefix.Address, ref); err != nil {
 			return nil, err
 		}
 	}
@@ -750,7 +762,7 @@ func (n *NIC) DeliverNetworkPacket(linkEP LinkEndpoint, remote, local tcpip.Link
 	}
 	n.mu.RUnlock()
 	for _, ep := range packetEPs {
-		ep.HandlePacket(n.id, local, protocol, vv, linkHeader)
+		ep.HandlePacket(n.id, local, protocol, vv.Clone(nil), linkHeader)
 	}
 
 	if netProto.Number() == header.IPv4ProtocolNumber || netProto.Number() == header.IPv6ProtocolNumber {
@@ -936,6 +948,18 @@ func (n *NIC) dupTentativeAddrDetected(addr tcpip.Address) *tcpip.Error {
 	return n.removePermanentAddressLocked(addr)
 }
 
+// setNDPConfigs sets the NDP configurations for n.
+//
+// Note, if c contains invalid NDP configuration values, it will be fixed to
+// use default values for the erroneous values.
+func (n *NIC) setNDPConfigs(c NDPConfigurations) {
+	c.validate()
+
+	n.mu.Lock()
+	n.ndp.configs = c
+	n.mu.Unlock()
+}
+
 type networkEndpointKind int32
 
 const (