NetBSD SO_TIMESTAMPNS option

--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1514,6 +1514,16 @@ void
 ip_savecontrol(struct inpcb *inp, struct mbuf **mp, struct ip *ip,
     struct mbuf *m)
 {
+       if (inp->inp_socket->so_options & SO_TIMESTAMPNS) {
+               struct timespec tc;
+
+               nanotime(&tc);
+               *mp = sbcreatecontrol((void *) &tc, sizeof(tc),
+                                                         SCM_TIMESTAMPNS, SOL_SOCKET);
+
+               if (*mp)
+                       mp = &(*mp)->m_next;
+       }

        if (inp->inp_socket->so_options & SO_TIMESTAMP
 #ifdef SO_OTIMESTAMP