No need to clear zone index.

--- sys/netinet6/send.c	(svn+ssh://svn.freebsd.org/base/head)	(revision 261548)
+++ sys/netinet6/send.c	(working copy)
@@ -54,7 +54,6 @@ __FBSDID("$FreeBSD$");
 
 #include <netinet6/in6_var.h>
 #include <netinet6/nd6.h>
-#include <netinet6/scope6_var.h>
 #include <netinet6/send.h>
 
 static MALLOC_DEFINE(M_SEND, "send", "Secure Neighbour Discovery");
@@ -258,7 +257,6 @@ send_close(struct socket *so)
 static int
 send_input(struct mbuf *m, struct ifnet *ifp, int direction, int msglen __unused)
 {
-	struct ip6_hdr *ip6;
 	struct sockaddr_send sendsrc;
 
 	SEND_LOCK();
@@ -267,15 +265,6 @@ send_input(struct mbuf *m, struct ifnet *ifp, int
 		return (-1);
 	}
 
-	/*
-	 * Make sure to clear any possible internally embedded scope before
-	 * passing the packet to user space for SeND cryptographic signature
-	 * validation to succeed.
-	 */
-	ip6 = mtod(m, struct ip6_hdr *);
-	in6_clearscope(&ip6->ip6_src);
-	in6_clearscope(&ip6->ip6_dst);
-
 	bzero(&sendsrc, sizeof(sendsrc));
 	sendsrc.send_len = sizeof(sendsrc);
 	sendsrc.send_family = AF_INET6;