diff --git a/sys/dev/iicbus/if_ic.c b/sys/dev/iicbus/if_ic.c
index fd072c123734..6579663d9564 100644
--- a/sys/dev/iicbus/if_ic.c
+++ b/sys/dev/iicbus/if_ic.c
@@ -99,7 +99,7 @@ static int icprobe(device_t);
 static int icattach(device_t);
 
 static int icioctl(struct ifnet *, u_long, caddr_t);
-static int icoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
+static int icoutput(struct ifnet *, struct mbuf *, const struct sockaddr *,
                struct route *);
 
 static int icintr(device_t, int, char *);
@@ -351,7 +351,7 @@ icintr(device_t dev, int event, char *ptr)
  * icoutput()
  */
 static int
-icoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+icoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
     struct route *ro)
 {
 	struct ic_softc *sc = ifp->if_softc;
diff --git a/sys/dev/lmc/if_lmc.c b/sys/dev/lmc/if_lmc.c
index 9d1ec8cdc847..49d0a5009c67 100644
--- a/sys/dev/lmc/if_lmc.c
+++ b/sys/dev/lmc/if_lmc.c
@@ -4587,7 +4587,7 @@ lmc_ifnet_start(struct ifnet *ifp)
 /* Called from a syscall (user context; no spinlocks). */
 static int
 lmc_raw_output(struct ifnet *ifp, struct mbuf *m,
- struct sockaddr *dst, struct route *ro)
+ const struct sockaddr *dst, struct route *ro)
   {
   softc_t *sc = IFP2SC(ifp);
   int error = 0;
diff --git a/sys/dev/lmc/if_lmc.h b/sys/dev/lmc/if_lmc.h
index 0212f514bf23..f3c19479556a 100644
--- a/sys/dev/lmc/if_lmc.h
+++ b/sys/dev/lmc/if_lmc.h
@@ -1595,7 +1595,7 @@ static int lmc_raw_ioctl(struct ifnet *, u_long, caddr_t);
 static int lmc_ifnet_ioctl(struct ifnet *, u_long, caddr_t);
 static void lmc_ifnet_start(struct ifnet *);
 static int lmc_raw_output(struct ifnet *, struct mbuf *,
- struct sockaddr *, struct route *);
+ const struct sockaddr *, struct route *);
 # ifdef __OpenBSD__
 static int ifmedia_change(struct ifnet *);
 static void ifmedia_status(struct ifnet *, struct ifmediareq *);
diff --git a/sys/dev/ppbus/if_plip.c b/sys/dev/ppbus/if_plip.c
index 281baf2e0e56..ceb4bce42506 100644
--- a/sys/dev/ppbus/if_plip.c
+++ b/sys/dev/ppbus/if_plip.c
@@ -173,7 +173,7 @@ static u_char *ctxmith;
 /* Functions for the lp# interface */
 static int lpinittables(void);
 static int lpioctl(struct ifnet *, u_long, caddr_t);
-static int lpoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
+static int lpoutput(struct ifnet *, struct mbuf *, const struct sockaddr *,
        struct route *);
 static void lpstop(struct lp_data *);
 static void lp_intr(void *);
@@ -682,7 +682,7 @@ lpoutbyte(u_char byte, int spin, device_t ppbus)
 }
 
 static int
-lpoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+lpoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
     struct route *ro)
 {
 	struct lp_data *sc = ifp->if_softc;
diff --git a/sys/dev/usb/net/if_usie.c b/sys/dev/usb/net/if_usie.c
index f3dbd9e15430..67f23b49232c 100644
--- a/sys/dev/usb/net/if_usie.c
+++ b/sys/dev/usb/net/if_usie.c
@@ -121,7 +121,8 @@ static void usie_if_sync_cb(void *, int);
 static void usie_if_status_cb(void *, int);
 
 static void usie_if_start(struct ifnet *);
-static int usie_if_output(struct ifnet *, struct mbuf *, struct sockaddr *, struct route *);
+static int usie_if_output(struct ifnet *, struct mbuf *,
+	const struct sockaddr *, struct route *);
 static void usie_if_init(void *);
 static void usie_if_stop(struct usie_softc *);
 static int usie_if_ioctl(struct ifnet *, u_long, caddr_t);
@@ -1181,7 +1182,7 @@ usie_if_start(struct ifnet *ifp)
 }
 
 static int
-usie_if_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+usie_if_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
     struct route *ro)
 {
 	int err;
diff --git a/sys/dev/usb/net/uhso.c b/sys/dev/usb/net/uhso.c
index 96c633533405..c56e1641cb31 100644
--- a/sys/dev/usb/net/uhso.c
+++ b/sys/dev/usb/net/uhso.c
@@ -467,8 +467,8 @@ static void uhso_if_init(void *);
 static void uhso_if_start(struct ifnet *);
 static void uhso_if_stop(struct uhso_softc *);
 static int  uhso_if_ioctl(struct ifnet *, u_long, caddr_t);
-static int  uhso_if_output(struct ifnet *, struct mbuf *, struct sockaddr *,
-    struct route *);
+static int  uhso_if_output(struct ifnet *, struct mbuf *,
+    const struct sockaddr *, struct route *);
 static void uhso_if_rxflush(void *);
 
 static device_probe_t uhso_probe;
@@ -1881,7 +1881,7 @@ uhso_if_init(void *priv)
 }
 
 static int
-uhso_if_output(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
+uhso_if_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst,
     struct route *ro)
 {
 	int error;
diff --git a/sys/net/ethernet.h b/sys/net/ethernet.h
index ae7341ee8191..10abf641d9fc 100644
--- a/sys/net/ethernet.h
+++ b/sys/net/ethernet.h
@@ -375,8 +375,8 @@ extern	void ether_demux(struct ifnet *, struct mbuf *);
 extern	void ether_ifattach(struct ifnet *, const u_int8_t *);
 extern	void ether_ifdetach(struct ifnet *);
 extern	int  ether_ioctl(struct ifnet *, u_long, caddr_t);
-extern	int  ether_output(struct ifnet *,
-		   struct mbuf *, struct sockaddr *, struct route *);
+extern	int  ether_output(struct ifnet *, struct mbuf *,
+	    const struct sockaddr *, struct route *);
 extern	int  ether_output_frame(struct ifnet *, struct mbuf *);
 extern	char *ether_sprintf(const u_int8_t *);
 void	ether_vlan_mtap(struct bpf_if *, struct mbuf *,
diff --git a/sys/net/if.c b/sys/net/if.c
index 712cd13ca23c..39dc941a485a 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -134,7 +134,7 @@ int	(*carp_master_p)(struct ifaddr *);
 #if defined(INET) || defined(INET6)
 int	(*carp_forus_p)(struct ifnet *ifp, u_char *dhost);
 int	(*carp_output_p)(struct ifnet *ifp, struct mbuf *m,
-    struct sockaddr *sa);
+    const struct sockaddr *sa);
 int	(*carp_ioctl_p)(struct ifreq *, u_long, struct thread *);   
 int	(*carp_attach_p)(struct ifaddr *, int);
 void	(*carp_detach_p)(struct ifaddr *);
diff --git a/sys/net/if_arc.h b/sys/net/if_arc.h
index 88a72403beee..23139aa6f669 100644
--- a/sys/net/if_arc.h
+++ b/sys/net/if_arc.h
@@ -133,7 +133,7 @@ void	arc_storelladdr(struct ifnet *, u_int8_t);
 int	arc_isphds(u_int8_t);
 void	arc_input(struct ifnet *, struct mbuf *);
 int	arc_output(struct ifnet *, struct mbuf *,
-	    struct sockaddr *, struct route *);
+	    const struct sockaddr *, struct route *);
 int	arc_ioctl(struct ifnet *, u_long, caddr_t);
 
 void		arc_frag_init(struct ifnet *);
diff --git a/sys/net/if_arcsubr.c b/sys/net/if_arcsubr.c
index 0371df76d018..2f9478582d11 100644
--- a/sys/net/if_arcsubr.c
+++ b/sys/net/if_arcsubr.c
@@ -92,8 +92,8 @@ u_int8_t  arcbroadcastaddr = 0;
 #define ARC_LLADDR(ifp)	(*(u_int8_t *)IF_LLADDR(ifp))
 
 #define senderr(e) { error = (e); goto bad;}
-#define SIN(s)	((struct sockaddr_in *)s)
-#define SIPX(s)	((struct sockaddr_ipx *)s)
+#define SIN(s)	((const struct sockaddr_in *)(s))
+#define SIPX(s)	((const struct sockaddr_ipx *)(s))
 
 /*
  * ARCnet output routine.
@@ -101,7 +101,7 @@ u_int8_t  arcbroadcastaddr = 0;
  * Assumes that ifp is actually pointer to arccom structure.
  */
 int
-arc_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+arc_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
     struct route *ro)
 {
 	struct arc_header	*ah;
@@ -186,8 +186,11 @@ arc_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 #endif
 
 	case AF_UNSPEC:
+	    {
+		const struct arc_header *ah;
+
 		loop_copy = -1;
-		ah = (struct arc_header *)dst->sa_data;
+		ah = (const struct arc_header *)dst->sa_data;
 		adst = ah->arc_dhost;
 		atype = ah->arc_type;
 
@@ -207,7 +210,7 @@ arc_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 #endif
 		}
 		break;
-
+	    }
 	default:
 		if_printf(ifp, "can't handle af%d\n", dst->sa_family);
 		senderr(EAFNOSUPPORT);
diff --git a/sys/net/if_atm.h b/sys/net/if_atm.h
index e8f69da09d02..c669c3dd3cac 100644
--- a/sys/net/if_atm.h
+++ b/sys/net/if_atm.h
@@ -292,7 +292,7 @@ void	atm_ifattach(struct ifnet *);
 void	atm_ifdetach(struct ifnet *);
 void	atm_input(struct ifnet *, struct atm_pseudohdr *,
 	    struct mbuf *, void *);
-int	atm_output(struct ifnet *, struct mbuf *, struct sockaddr *, 
+int	atm_output(struct ifnet *, struct mbuf *, const struct sockaddr *, 
 	    struct route *);
 struct atmio_vcctable *atm_getvccs(struct atmio_vcc **, u_int, u_int,
 	    struct mtx *, int);
diff --git a/sys/net/if_atmsubr.c b/sys/net/if_atmsubr.c
index fdb8931ec76b..d6190ec9fcd3 100644
--- a/sys/net/if_atmsubr.c
+++ b/sys/net/if_atmsubr.c
@@ -121,7 +121,7 @@ static MALLOC_DEFINE(M_IFATM, "ifatm", "atm interface internals");
  *		ro->ro_rt must also be NULL.
  */
 int
-atm_output(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
+atm_output(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst,
     struct route *ro)
 {
 	u_int16_t etype = 0;			/* if using LLC/SNAP */
@@ -129,7 +129,7 @@ atm_output(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
 	struct atm_pseudohdr atmdst, *ad;
 	struct mbuf *m = m0;
 	struct atmllc *atmllc;
-	struct atmllc *llc_hdr = NULL;
+	const struct atmllc *llc_hdr = NULL;
 	u_int32_t atm_flags;
 
 #ifdef MAC
@@ -173,7 +173,7 @@ atm_output(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
 			 * (atm pseudo header (4) + LLC/SNAP (8))
 			 */
 			bcopy(dst->sa_data, &atmdst, sizeof(atmdst));
-			llc_hdr = (struct atmllc *)(dst->sa_data +
+			llc_hdr = (const struct atmllc *)(dst->sa_data +
 			    sizeof(atmdst));
 			break;
 			
diff --git a/sys/net/if_dead.c b/sys/net/if_dead.c
index 7c941d830522..cd6dff365fb3 100644
--- a/sys/net/if_dead.c
+++ b/sys/net/if_dead.c
@@ -42,7 +42,7 @@ __FBSDID("$FreeBSD$");
 #include <net/if_var.h>
 
 static int
-ifdead_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *sa,
+ifdead_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa,
     struct route *ro)
 {
 
diff --git a/sys/net/if_disc.c b/sys/net/if_disc.c
index f2f902e12ccf..16a1e7b02f44 100644
--- a/sys/net/if_disc.c
+++ b/sys/net/if_disc.c
@@ -64,7 +64,7 @@ struct disc_softc {
 };
 
 static int	discoutput(struct ifnet *, struct mbuf *,
-		    struct sockaddr *, struct route *);
+		    const struct sockaddr *, struct route *);
 static void	discrtrequest(int, struct rtentry *, struct rt_addrinfo *);
 static int	discioctl(struct ifnet *, u_long, caddr_t);
 static int	disc_clone_create(struct if_clone *, int, caddr_t);
@@ -155,7 +155,7 @@ static moduledata_t disc_mod = {
 DECLARE_MODULE(if_disc, disc_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
 
 static int
-discoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+discoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
     struct route *ro)
 {
 	u_int32_t af;
@@ -163,15 +163,14 @@ discoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 	M_ASSERTPKTHDR(m);
 
 	/* BPF writes need to be handled specially. */
-	if (dst->sa_family == AF_UNSPEC) {
+	if (dst->sa_family == AF_UNSPEC)
 		bcopy(dst->sa_data, &af, sizeof(af));
-		dst->sa_family = af;
-	}
+	else
+		af = dst->sa_family;
 
-	if (bpf_peers_present(ifp->if_bpf)) {
-		u_int af = dst->sa_family;
+	if (bpf_peers_present(ifp->if_bpf))
 		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
-	}
+
 	m->m_pkthdr.rcvif = ifp;
 
 	ifp->if_opackets++;
diff --git a/sys/net/if_ef.c b/sys/net/if_ef.c
index 94337934b521..fc6402c137d7 100644
--- a/sys/net/if_ef.c
+++ b/sys/net/if_ef.c
@@ -102,7 +102,7 @@ static int efcount;
 
 extern int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m);
 extern int (*ef_outputp)(struct ifnet *ifp, struct mbuf **mp,
-		struct sockaddr *dst, short *tp, int *hlen);
+		const struct sockaddr *dst, short *tp, int *hlen);
 
 /*
 static void ef_reset (struct ifnet *);
@@ -114,7 +114,7 @@ static int ef_ioctl(struct ifnet *, u_long, caddr_t);
 static void ef_start(struct ifnet *);
 static int ef_input(struct ifnet*, struct ether_header *, struct mbuf *);
 static int ef_output(struct ifnet *ifp, struct mbuf **mp,
-		struct sockaddr *dst, short *tp, int *hlen);
+		const struct sockaddr *dst, short *tp, int *hlen);
 
 static int ef_load(void);
 static int ef_unload(void);
@@ -386,8 +386,8 @@ ef_input(struct ifnet *ifp, struct ether_header *eh, struct mbuf *m)
 }
 
 static int
-ef_output(struct ifnet *ifp, struct mbuf **mp, struct sockaddr *dst, short *tp,
-	int *hlen)
+ef_output(struct ifnet *ifp, struct mbuf **mp, const struct sockaddr *dst,
+	short *tp, int *hlen)
 {
 	struct efnet *sc = (struct efnet*)ifp->if_softc;
 	struct mbuf *m = *mp;
diff --git a/sys/net/if_enc.c b/sys/net/if_enc.c
index ecc24151567e..e49f40c18db5 100644
--- a/sys/net/if_enc.c
+++ b/sys/net/if_enc.c
@@ -88,7 +88,7 @@ struct enc_softc {
 
 static int	enc_ioctl(struct ifnet *, u_long, caddr_t);
 static int	enc_output(struct ifnet *ifp, struct mbuf *m,
-		    struct sockaddr *dst, struct route *ro);
+		    const struct sockaddr *dst, struct route *ro);
 static int	enc_clone_create(struct if_clone *, int, caddr_t);
 static void	enc_clone_destroy(struct ifnet *);
 static struct if_clone *enc_cloner;
@@ -188,7 +188,7 @@ static moduledata_t enc_mod = {
 DECLARE_MODULE(if_enc, enc_mod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY);
 
 static int
-enc_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+enc_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
     struct route *ro)
 {
 	m_freem(m);
diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index bb4029e95dfc..6a42214e4a83 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -83,7 +83,7 @@
 
 int (*ef_inputp)(struct ifnet*, struct ether_header *eh, struct mbuf *m);
 int (*ef_outputp)(struct ifnet *ifp, struct mbuf **mp,
-		struct sockaddr *dst, short *tp, int *hlen);
+		const struct sockaddr *dst, short *tp, int *hlen);
 
 #ifdef NETATALK
 #include <netatalk/at.h>
@@ -149,7 +149,7 @@ static MALLOC_DEFINE(M_ARPCOM, "arpcom", "802.* interface internals");
  */
 int
 ether_output(struct ifnet *ifp, struct mbuf *m,
-	struct sockaddr *dst, struct route *ro)
+	const struct sockaddr *dst, struct route *ro)
 {
 	short type;
 	int error = 0, hdrcmplt = 0;
@@ -238,8 +238,8 @@ ether_output(struct ifnet *ifp, struct mbuf *m,
 			goto bad;
 		} else
 		    type = htons(ETHERTYPE_IPX);
-		bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host),
-		    (caddr_t)edst, sizeof (edst));
+		bcopy(&((const struct sockaddr_ipx *)dst)->sipx_addr.x_host,
+		    edst, sizeof (edst));
 		break;
 #endif
 #ifdef NETATALK
@@ -247,9 +247,9 @@ ether_output(struct ifnet *ifp, struct mbuf *m,
 	  {
 	    struct at_ifaddr *aa;
 
-	    if ((aa = at_ifawithnet((struct sockaddr_at *)dst)) == NULL)
+	    if ((aa = at_ifawithnet((const struct sockaddr_at *)dst)) == NULL)
 		    senderr(EHOSTUNREACH); /* XXX */
-	    if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst)) {
+	    if (!aarpresolve(ifp, m, (const struct sockaddr_at *)dst, edst)) {
 		    ifa_free(&aa->aa_ifa);
 		    return (0);
 	    }
@@ -279,18 +279,21 @@ ether_output(struct ifnet *ifp, struct mbuf *m,
 #endif /* NETATALK */
 
 	case pseudo_AF_HDRCMPLT:
+	    {
+		const struct ether_header *eh;
+		
 		hdrcmplt = 1;
-		eh = (struct ether_header *)dst->sa_data;
+		eh = (const struct ether_header *)dst->sa_data;
 		(void)memcpy(esrc, eh->ether_shost, sizeof (esrc));
 		/* FALLTHROUGH */
 
 	case AF_UNSPEC:
 		loop_copy = 0; /* if this is for us, don't do it */
-		eh = (struct ether_header *)dst->sa_data;
+		eh = (const struct ether_header *)dst->sa_data;
 		(void)memcpy(edst, eh->ether_dhost, sizeof (edst));
 		type = eh->ether_type;
 		break;
-
+            }
 	default:
 		if_printf(ifp, "can't handle af%d\n", dst->sa_family);
 		senderr(EAFNOSUPPORT);
diff --git a/sys/net/if_faith.c b/sys/net/if_faith.c
index 907dcce9139f..37a53bbeb8f3 100644
--- a/sys/net/if_faith.c
+++ b/sys/net/if_faith.c
@@ -84,7 +84,7 @@ struct faith_softc {
 };
 
 static int faithioctl(struct ifnet *, u_long, caddr_t);
-int faithoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
+static int faithoutput(struct ifnet *, struct mbuf *, const struct sockaddr *,
 	struct route *);
 static void faithrtrequest(int, struct rtentry *, struct rt_addrinfo *);
 #ifdef INET6
@@ -184,12 +184,9 @@ faith_clone_destroy(ifp)
 	free(sc, M_FAITH);
 }
 
-int
-faithoutput(ifp, m, dst, ro)
-	struct ifnet *ifp;
-	struct mbuf *m;
-	struct sockaddr *dst;
-	struct route *ro;
+static int
+faithoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
+	struct route *ro)
 {
 	int isr;
 	u_int32_t af;
@@ -200,15 +197,13 @@ faithoutput(ifp, m, dst, ro)
 	if (ro != NULL)
 		rt = ro->ro_rt;
 	/* BPF writes need to be handled specially. */
-	if (dst->sa_family == AF_UNSPEC) {
+	if (dst->sa_family == AF_UNSPEC)
 		bcopy(dst->sa_data, &af, sizeof(af));
-		dst->sa_family = af;
-	}
-
-	if (bpf_peers_present(ifp->if_bpf)) {
+	else
 		af = dst->sa_family;
+
+	if (bpf_peers_present(ifp->if_bpf))
 		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
-	}
 
 	if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
 		m_freem(m);
@@ -217,7 +212,7 @@ faithoutput(ifp, m, dst, ro)
 	}
 	ifp->if_opackets++;
 	ifp->if_obytes += m->m_pkthdr.len;
-	switch (dst->sa_family) {
+	switch (af) {
 #ifdef INET
 	case AF_INET:
 		isr = NETISR_IP;
diff --git a/sys/net/if_fddisubr.c b/sys/net/if_fddisubr.c
index 57fb27d36d51..5e7dbe626967 100644
--- a/sys/net/if_fddisubr.c
+++ b/sys/net/if_fddisubr.c
@@ -96,7 +96,7 @@ static const u_char fddibroadcastaddr[FDDI_ADDR_LEN] =
 
 static int fddi_resolvemulti(struct ifnet *, struct sockaddr **,
 			      struct sockaddr *);
-static int fddi_output(struct ifnet *, struct mbuf *, struct sockaddr *,
+static int fddi_output(struct ifnet *, struct mbuf *, const struct sockaddr *,
 		       struct route *); 
 static void fddi_input(struct ifnet *ifp, struct mbuf *m);
 
@@ -110,11 +110,8 @@ static void fddi_input(struct ifnet *ifp, struct mbuf *m);
  * Assumes that ifp is actually pointer to arpcom structure.
  */
 static int
-fddi_output(ifp, m, dst, ro)
-	struct ifnet *ifp;
-	struct mbuf *m;
-	struct sockaddr *dst;
-	struct route *ro;
+fddi_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
+	struct route *ro)
 {
 	u_int16_t type;
 	int loop_copy = 0, error = 0, hdrcmplt = 0;
@@ -189,19 +186,19 @@ fddi_output(ifp, m, dst, ro)
 #ifdef IPX
 	case AF_IPX:
 		type = htons(ETHERTYPE_IPX);
- 		bcopy((caddr_t)&(((struct sockaddr_ipx *)dst)->sipx_addr.x_host),
-		    (caddr_t)edst, FDDI_ADDR_LEN);
+ 		bcopy(&((const struct sockaddr_ipx *)dst)->sipx_addr.x_host,
+		    edst, FDDI_ADDR_LEN);
 		break;
 #endif /* IPX */
 #ifdef NETATALK
 	case AF_APPLETALK: {
 	    struct at_ifaddr *aa;
-            if (!aarpresolve(ifp, m, (struct sockaddr_at *)dst, edst))
+            if (!aarpresolve(ifp, m, (const struct sockaddr_at *)dst, edst))
                 return (0);
 	    /*
 	     * ifaddr is the first thing in at_ifaddr
 	     */
-	    if ((aa = at_ifawithnet( (struct sockaddr_at *)dst)) == 0)
+	    if ((aa = at_ifawithnet((const struct sockaddr_at *)dst)) == 0)
 		goto bad;
 	    
 	    /*
@@ -229,19 +226,21 @@ fddi_output(ifp, m, dst, ro)
 
 	case pseudo_AF_HDRCMPLT:
 	{
-		struct ether_header *eh;
+		const struct ether_header *eh;
+
 		hdrcmplt = 1;
-		eh = (struct ether_header *)dst->sa_data;
-		bcopy((caddr_t)eh->ether_shost, (caddr_t)esrc, FDDI_ADDR_LEN);
+		eh = (const struct ether_header *)dst->sa_data;
+		bcopy(eh->ether_shost, esrc, FDDI_ADDR_LEN);
 		/* FALLTHROUGH */
 	}
 
 	case AF_UNSPEC:
 	{
-		struct ether_header *eh;
+		const struct ether_header *eh;
+
 		loop_copy = -1;
-		eh = (struct ether_header *)dst->sa_data;
-		bcopy((caddr_t)eh->ether_dhost, (caddr_t)edst, FDDI_ADDR_LEN);
+		eh = (const struct ether_header *)dst->sa_data;
+		bcopy(eh->ether_dhost, edst, FDDI_ADDR_LEN);
 		if (*edst & 1)
 			m->m_flags |= (M_BCAST|M_MCAST);
 		type = eh->ether_type;
diff --git a/sys/net/if_fwsubr.c b/sys/net/if_fwsubr.c
index e1d5c01022a6..31fc2a949bf3 100644
--- a/sys/net/if_fwsubr.c
+++ b/sys/net/if_fwsubr.c
@@ -75,7 +75,7 @@ struct fw_hwaddr firewire_broadcastaddr = {
 };
 
 static int
-firewire_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+firewire_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
     struct route *ro)
 {
 	struct fw_com *fc = IFP2FWC(ifp);
diff --git a/sys/net/if_gif.c b/sys/net/if_gif.c
index 9fef6c7e6361..2a6f8902678e 100644
--- a/sys/net/if_gif.c
+++ b/sys/net/if_gif.c
@@ -422,11 +422,8 @@ gif_start(struct ifnet *ifp)
 }
 
 int
-gif_output(ifp, m, dst, ro)
-	struct ifnet *ifp;
-	struct mbuf *m;
-	struct sockaddr *dst;
-	struct route *ro;
+gif_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
+	struct route *ro)
 {
 	struct gif_softc *sc = ifp->if_softc;
 	struct m_tag *mtag;
@@ -482,11 +479,10 @@ gif_output(ifp, m, dst, ro)
 
 	m->m_flags &= ~(M_BCAST|M_MCAST);
 	/* BPF writes need to be handled specially. */
-	if (dst->sa_family == AF_UNSPEC) {
+	if (dst->sa_family == AF_UNSPEC)
 		bcopy(dst->sa_data, &af, sizeof(af));
-		dst->sa_family = af;
-	}
-	af = dst->sa_family;
+	else
+		af = dst->sa_family;
 	/* 
 	 * Now save the af in the inbound pkt csum
 	 * data, this is a cheat since we are using
diff --git a/sys/net/if_gif.h b/sys/net/if_gif.h
index 5d0db6d14337..d6e58f5c1b61 100644
--- a/sys/net/if_gif.h
+++ b/sys/net/if_gif.h
@@ -112,7 +112,7 @@ struct etherip_header {
 
 /* Prototypes */
 void gif_input(struct mbuf *, int, struct ifnet *);
-int gif_output(struct ifnet *, struct mbuf *, struct sockaddr *,
+int gif_output(struct ifnet *, struct mbuf *, const struct sockaddr *,
 	       struct route *);
 int gif_ioctl(struct ifnet *, u_long, caddr_t);
 int gif_set_tunnel(struct ifnet *, struct sockaddr *, struct sockaddr *);
diff --git a/sys/net/if_gre.c b/sys/net/if_gre.c
index 48255b06a7ad..3d337669ed1f 100644
--- a/sys/net/if_gre.c
+++ b/sys/net/if_gre.c
@@ -113,8 +113,8 @@ static void	gre_clone_destroy(struct ifnet *);
 static struct if_clone *gre_cloner;
 
 static int	gre_ioctl(struct ifnet *, u_long, caddr_t);
-static int	gre_output(struct ifnet *, struct mbuf *, struct sockaddr *,
-		    struct route *ro);
+static int	gre_output(struct ifnet *, struct mbuf *,
+		    const struct sockaddr *, struct route *);
 
 static int gre_compute_route(struct gre_softc *sc);
 
@@ -241,7 +241,7 @@ gre_clone_destroy(ifp)
  * given by sc->g_proto. See also RFC 1701 and RFC 2004
  */
 static int
-gre_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+gre_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
 	   struct route *ro)
 {
 	int error = 0;
@@ -333,20 +333,18 @@ gre_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 	ip = NULL;
 
 	/* BPF writes need to be handled specially. */
-	if (dst->sa_family == AF_UNSPEC) {
+	if (dst->sa_family == AF_UNSPEC)
 		bcopy(dst->sa_data, &af, sizeof(af));
-		dst->sa_family = af;
-	}
-
-	if (bpf_peers_present(ifp->if_bpf)) {
+	else
 		af = dst->sa_family;
+
+	if (bpf_peers_present(ifp->if_bpf))
 		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
-	}
 
 	m->m_flags &= ~(M_BCAST|M_MCAST);
 
 	if (sc->g_proto == IPPROTO_MOBILE) {
-		if (dst->sa_family == AF_INET) {
+		if (af == AF_INET) {
 			struct mbuf *m0;
 			int msiz;
 
@@ -417,7 +415,7 @@ gre_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 			goto end;
 		}
 	} else if (sc->g_proto == IPPROTO_GRE) {
-		switch (dst->sa_family) {
+		switch (af) {
 		case AF_INET:
 			ip = mtod(m, struct ip *);
 			gre_ip_tos = ip->ip_tos;
diff --git a/sys/net/if_iso88025subr.c b/sys/net/if_iso88025subr.c
index 7f9e8bd10ae0..63b210760e60 100644
--- a/sys/net/if_iso88025subr.c
+++ b/sys/net/if_iso88025subr.c
@@ -231,11 +231,8 @@ iso88025_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
  * ISO88025 encapsulation
  */
 int
-iso88025_output(ifp, m, dst, ro)
-	struct ifnet *ifp;
-	struct mbuf *m;
-	struct sockaddr *dst;
-	struct route *ro;
+iso88025_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
+	struct route *ro)
 {
 	u_int16_t snap_type = 0;
 	int loop_copy = 0, error = 0, rif_len = 0;
@@ -351,7 +348,7 @@ iso88025_output(ifp, m, dst, ro)
 #endif	/* IPX */
 	case AF_UNSPEC:
 	{
-		struct iso88025_sockaddr_data *sd;
+		const struct iso88025_sockaddr_data *sd;
 		/*
 		 * For AF_UNSPEC sockaddr.sa_data must contain all of the
 		 * mac information needed to send the packet.  This allows
@@ -361,13 +358,12 @@ iso88025_output(ifp, m, dst, ro)
 		 * should be an iso88025_sockaddr_data structure see iso88025.h
 		 */
                 loop_copy = -1;
-		sd = (struct iso88025_sockaddr_data *)dst->sa_data;
+		sd = (const struct iso88025_sockaddr_data *)dst->sa_data;
 		gen_th.ac = sd->ac;
 		gen_th.fc = sd->fc;
-		(void)memcpy((caddr_t)edst, (caddr_t)sd->ether_dhost,
-			     ISO88025_ADDR_LEN);
-		(void)memcpy((caddr_t)gen_th.iso88025_shost,
-			     (caddr_t)sd->ether_shost, ISO88025_ADDR_LEN);
+		(void)memcpy(edst, sd->ether_dhost, ISO88025_ADDR_LEN);
+		(void)memcpy(gen_th.iso88025_shost, sd->ether_shost,
+		    ISO88025_ADDR_LEN);
 		rif_len = 0;
 		break;
 	}
diff --git a/sys/net/if_lagg.c b/sys/net/if_lagg.c
index 0f5ca0d2178a..5688b76e1d50 100644
--- a/sys/net/if_lagg.c
+++ b/sys/net/if_lagg.c
@@ -99,7 +99,7 @@ static void	lagg_linkstate(struct lagg_softc *);
 static void	lagg_port_state(struct ifnet *, int);
 static int	lagg_port_ioctl(struct ifnet *, u_long, caddr_t);
 static int	lagg_port_output(struct ifnet *, struct mbuf *,
-		    struct sockaddr *, struct route *);
+		    const struct sockaddr *, struct route *);
 static void	lagg_port_ifdetach(void *arg __unused, struct ifnet *);
 #ifdef LAGG_PORT_STACKING
 static int	lagg_port_checkstacking(struct lagg_softc *);
@@ -787,7 +787,7 @@ lagg_port_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
  */
 static int
 lagg_port_output(struct ifnet *ifp, struct mbuf *m,
-	struct sockaddr *dst, struct route *ro)
+	const struct sockaddr *dst, struct route *ro)
 {
 	struct lagg_port *lp = ifp->if_lagg;
 
diff --git a/sys/net/if_lagg.h b/sys/net/if_lagg.h
index 7170128f9918..fe3365bcf66b 100644
--- a/sys/net/if_lagg.h
+++ b/sys/net/if_lagg.h
@@ -245,8 +245,8 @@ struct lagg_port {
 
 	/* Redirected callbacks */
 	int	(*lp_ioctl)(struct ifnet *, u_long, caddr_t);
-	int	(*lp_output)(struct ifnet *, struct mbuf *, struct sockaddr *,
-		     struct route *);
+	int	(*lp_output)(struct ifnet *, struct mbuf *,
+		     const struct sockaddr *, struct route *);
 
 	SLIST_ENTRY(lagg_port)		lp_entries;
 };
diff --git a/sys/net/if_loop.c b/sys/net/if_loop.c
index acf8012c96bf..499cd2c06f8e 100644
--- a/sys/net/if_loop.c
+++ b/sys/net/if_loop.c
@@ -101,7 +101,7 @@
 int		loioctl(struct ifnet *, u_long, caddr_t);
 static void	lortrequest(int, struct rtentry *, struct rt_addrinfo *);
 int		looutput(struct ifnet *ifp, struct mbuf *m,
-		    struct sockaddr *dst, struct route *ro);
+		    const struct sockaddr *dst, struct route *ro);
 static int	lo_clone_create(struct if_clone *, int, caddr_t);
 static void	lo_clone_destroy(struct ifnet *);
 
@@ -210,7 +210,7 @@ static moduledata_t loop_mod = {
 DECLARE_MODULE(if_lo, loop_mod, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY);
 
 int
-looutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+looutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
     struct route *ro)
 {
 	u_int32_t af;
@@ -241,13 +241,13 @@ looutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 	ifp->if_obytes += m->m_pkthdr.len;
 
 	/* BPF writes need to be handled specially. */
-	if (dst->sa_family == AF_UNSPEC) {
+	if (dst->sa_family == AF_UNSPEC)
 		bcopy(dst->sa_data, &af, sizeof(af));
-		dst->sa_family = af;
-	}
+	else
+		af = dst->sa_family;
 
 #if 1	/* XXX */
-	switch (dst->sa_family) {
+	switch (af) {
 	case AF_INET:
 		if (ifp->if_capenable & IFCAP_RXCSUM) {
 			m->m_pkthdr.csum_data = 0xffff;
@@ -276,12 +276,12 @@ looutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
 	case AF_APPLETALK:
 		break;
 	default:
-		printf("looutput: af=%d unexpected\n", dst->sa_family);
+		printf("looutput: af=%d unexpected\n", af);
 		m_freem(m);
 		return (EAFNOSUPPORT);
 	}
 #endif
-	return (if_simloop(ifp, m, dst->sa_family, 0));
+	return (if_simloop(ifp, m, af, 0));
 }
 
 /*
diff --git a/sys/net/if_spppsubr.c b/sys/net/if_spppsubr.c
index 23851099f81b..1c6399f11b26 100644
--- a/sys/net/if_spppsubr.c
+++ b/sys/net/if_spppsubr.c
@@ -262,7 +262,7 @@ static const u_short interactive_ports[8] = {
 	int debug = ifp->if_flags & IFF_DEBUG
 
 static int sppp_output(struct ifnet *ifp, struct mbuf *m,
-		       struct sockaddr *dst, struct route *ro);
+	const struct sockaddr *dst, struct route *ro);
 
 static void sppp_cisco_send(struct sppp *sp, int type, long par1, long par2);
 static void sppp_cisco_input(struct sppp *sp, struct mbuf *m);
@@ -785,8 +785,8 @@ sppp_ifstart(struct ifnet *ifp)
  * Enqueue transmit packet.
  */
 static int
-sppp_output(struct ifnet *ifp, struct mbuf *m,
-	    struct sockaddr *dst, struct route *ro)
+sppp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
+	struct route *ro)
 {
 	struct sppp *sp = IFP2SP(ifp);
 	struct ppp_header *h;
diff --git a/sys/net/if_stf.c b/sys/net/if_stf.c
index c8f2ec8802dd..2c347398be66 100644
--- a/sys/net/if_stf.c
+++ b/sys/net/if_stf.c
@@ -140,7 +140,7 @@ SYSCTL_INT(_net_link_stf, OID_AUTO, permit_rfc1918, CTLFLAG_RW | CTLFLAG_TUN,
  * XXX: Return a pointer with 16-bit aligned.  Don't cast it to
  * struct in_addr *; use bcopy() instead.
  */
-#define GET_V4(x)	((caddr_t)(&(x)->s6_addr16[1]))
+#define GET_V4(x)	(&(x)->s6_addr16[1])
 
 struct stf_softc {
 	struct ifnet	*sc_ifp;
@@ -181,7 +181,7 @@ static char *stfnames[] = {"stf0", "stf", "6to4", NULL};
 static int stfmodevent(module_t, int, void *);
 static int stf_encapcheck(const struct mbuf *, int, int, void *);
 static struct in6_ifaddr *stf_getsrcifa6(struct ifnet *);
-static int stf_output(struct ifnet *, struct mbuf *, struct sockaddr *,
+static int stf_output(struct ifnet *, struct mbuf *, const struct sockaddr *,
 	struct route *);
 static int isrfc1918addr(struct in_addr *);
 static int stf_checkaddr4(struct stf_softc *, struct in_addr *,
@@ -413,23 +413,19 @@ stf_getsrcifa6(ifp)
 }
 
 static int
-stf_output(ifp, m, dst, ro)
-	struct ifnet *ifp;
-	struct mbuf *m;
-	struct sockaddr *dst;
-	struct route *ro;
+stf_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
+	struct route *ro)
 {
 	struct stf_softc *sc;
-	struct sockaddr_in6 *dst6;
+	const struct sockaddr_in6 *dst6;
 	struct route *cached_route;
 	struct in_addr in4;
-	caddr_t ptr;
+	const void *ptr;
 	struct sockaddr_in *dst4;
 	u_int8_t tos;
 	struct ip *ip;
 	struct ip6_hdr *ip6;
 	struct in6_ifaddr *ia6;
-	u_int32_t af;
 	int error;
 
 #ifdef MAC
@@ -441,7 +437,7 @@ stf_output(ifp, m, dst, ro)
 #endif
 
 	sc = ifp->if_softc;
-	dst6 = (struct sockaddr_in6 *)dst;
+	dst6 = (const struct sockaddr_in6 *)dst;
 
 	/* just in case */
 	if ((ifp->if_flags & IFF_UP) == 0) {
@@ -473,15 +469,6 @@ stf_output(ifp, m, dst, ro)
 	ip6 = mtod(m, struct ip6_hdr *);
 	tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
 
-	/*
-	 * BPF writes need to be handled specially.
-	 * This is a null operation, nothing here checks dst->sa_family.
-	 */
-	if (dst->sa_family == AF_UNSPEC) {
-		bcopy(dst->sa_data, &af, sizeof(af));
-		dst->sa_family = af;
-	}
-
 	/*
 	 * Pickup the right outer dst addr from the list of candidates.
 	 * ip6_dst has priority as it may be able to give us shorter IPv4 hops.
@@ -507,7 +494,7 @@ stf_output(ifp, m, dst, ro)
 		 * will only read from the mbuf (i.e., it won't
 		 * try to free it or keep a pointer a to it).
 		 */
-		af = AF_INET6;
+		u_int af = AF_INET6;
 		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m);
 	}
 
diff --git a/sys/net/if_tun.c b/sys/net/if_tun.c
index 3630732deedd..d88502493f18 100644
--- a/sys/net/if_tun.c
+++ b/sys/net/if_tun.c
@@ -128,8 +128,8 @@ static void	tuncreate(const char *name, struct cdev *dev);
 static int	tunifioctl(struct ifnet *, u_long, caddr_t);
 static void	tuninit(struct ifnet *);
 static int	tunmodevent(module_t, int, void *);
-static int	tunoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
-		    struct route *ro);
+static int	tunoutput(struct ifnet *, struct mbuf *,
+		    const struct sockaddr *, struct route *ro);
 static void	tunstart(struct ifnet *);
 
 static int	tun_clone_create(struct if_clone *, int, caddr_t);
@@ -575,7 +575,7 @@ tunifioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
  * tunoutput - queue packets from higher level ready to put out.
  */
 static int
-tunoutput(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
+tunoutput(struct ifnet *ifp, struct mbuf *m0, const struct sockaddr *dst,
     struct route *ro)
 {
 	struct tun_softc *tp = ifp->if_softc;
@@ -609,15 +609,13 @@ tunoutput(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
 	}
 
 	/* BPF writes need to be handled specially. */
-	if (dst->sa_family == AF_UNSPEC) {
+	if (dst->sa_family == AF_UNSPEC)
 		bcopy(dst->sa_data, &af, sizeof(af));
-		dst->sa_family = af; 
-	}
-
-	if (bpf_peers_present(ifp->if_bpf)) {
+	else
 		af = dst->sa_family;
+
+	if (bpf_peers_present(ifp->if_bpf))
 		bpf_mtap2(ifp->if_bpf, &af, sizeof(af), m0);
-	}
 
 	/* prepend sockaddr? this may abort if the mbuf allocation fails */
 	if (cached_tun_flags & TUN_LMODE) {
@@ -644,10 +642,10 @@ tunoutput(struct ifnet *ifp, struct mbuf *m0, struct sockaddr *dst,
 			ifp->if_oerrors++;
 			return (ENOBUFS);
 		} else
-			*(u_int32_t *)m0->m_data = htonl(dst->sa_family);
+			*(u_int32_t *)m0->m_data = htonl(af);
 	} else {
 #ifdef INET
-		if (dst->sa_family != AF_INET)
+		if (af != AF_INET)
 #endif
 		{
 			m_freem(m0);
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 6b3a4684075a..41ac056c3d57 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -158,7 +158,7 @@ struct ifnet {
 	int	if_amcount;		/* number of all-multicast requests */
 /* procedure handles */
 	int	(*if_output)		/* output routine (enqueue) */
-		(struct ifnet *, struct mbuf *, struct sockaddr *,
+		(struct ifnet *, struct mbuf *, const struct sockaddr *,
 		     struct route *);
 	void	(*if_input)		/* input routine (from h/w driver) */
 		(struct ifnet *, struct mbuf *);
diff --git a/sys/net/iso88025.h b/sys/net/iso88025.h
index 6edd2e0b1bc7..2faab843d823 100644
--- a/sys/net/iso88025.h
+++ b/sys/net/iso88025.h
@@ -165,8 +165,8 @@ struct	iso88025_addr {
 void	iso88025_ifattach	(struct ifnet *, const u_int8_t *, int);
 void	iso88025_ifdetach	(struct ifnet *, int);
 int	iso88025_ioctl		(struct ifnet *, u_long, caddr_t );
-int	iso88025_output		(struct ifnet *, struct mbuf *, struct sockaddr *,
-    				 struct route *);
+int	iso88025_output		(struct ifnet *, struct mbuf *,
+				 const struct sockaddr *, struct route *);
 void	iso88025_input		(struct ifnet *, struct mbuf *);
 
 #endif
diff --git a/sys/net80211/ieee80211.c b/sys/net80211/ieee80211.c
index c5ebc62a1b22..6b6987d69dc3 100644
--- a/sys/net80211/ieee80211.c
+++ b/sys/net80211/ieee80211.c
@@ -243,7 +243,7 @@ null_transmit(struct ifnet *ifp, struct mbuf *m)
 
 static int
 null_output(struct ifnet *ifp, struct mbuf *m,
-	struct sockaddr *dst, struct route *ro)
+	const struct sockaddr *dst, struct route *ro)
 {
 	if_printf(ifp, "discard raw packet\n");
 	return null_transmit(ifp, m);
diff --git a/sys/net80211/ieee80211_output.c b/sys/net80211/ieee80211_output.c
index 675c87b1b239..e9ba1673f941 100644
--- a/sys/net80211/ieee80211_output.c
+++ b/sys/net80211/ieee80211_output.c
@@ -450,7 +450,7 @@ ieee80211_raw_output(struct ieee80211vap *vap, struct ieee80211_node *ni,
  */
 int
 ieee80211_output(struct ifnet *ifp, struct mbuf *m,
-	struct sockaddr *dst, struct route *ro)
+	const struct sockaddr *dst, struct route *ro)
 {
 #define senderr(e) do { error = (e); goto bad;} while (0)
 	struct ieee80211_node *ni = NULL;
diff --git a/sys/net80211/ieee80211_proto.h b/sys/net80211/ieee80211_proto.h
index a73df52fbab1..e4bca5b51603 100644
--- a/sys/net80211/ieee80211_proto.h
+++ b/sys/net80211/ieee80211_proto.h
@@ -97,7 +97,7 @@ int	ieee80211_mgmt_output(struct ieee80211_node *, struct mbuf *, int,
 int	ieee80211_raw_xmit(struct ieee80211_node *, struct mbuf *,
 		const struct ieee80211_bpf_params *);
 int	ieee80211_output(struct ifnet *, struct mbuf *,
-               struct sockaddr *, struct route *ro);
+               const struct sockaddr *, struct route *ro);
 int	ieee80211_raw_output(struct ieee80211vap *, struct ieee80211_node *,
 		struct mbuf *, const struct ieee80211_bpf_params *);
 void	ieee80211_send_setup(struct ieee80211_node *, struct mbuf *, int, int,
diff --git a/sys/net80211/ieee80211_var.h b/sys/net80211/ieee80211_var.h
index 9593ffe58f7d..f35506e5a1e6 100644
--- a/sys/net80211/ieee80211_var.h
+++ b/sys/net80211/ieee80211_var.h
@@ -497,7 +497,7 @@ struct ieee80211vap {
 				    enum ieee80211_state, int);
 	/* 802.3 output method for raw frame xmit */
 	int			(*iv_output)(struct ifnet *, struct mbuf *,
-				    struct sockaddr *, struct route *);
+				    const struct sockaddr *, struct route *);
 	uint64_t		iv_spare[6];
 };
 MALLOC_DECLARE(M_80211_VAP);
diff --git a/sys/netatalk/aarp.c b/sys/netatalk/aarp.c
index 4426d57c11fa..8d4f76fddd4c 100644
--- a/sys/netatalk/aarp.c
+++ b/sys/netatalk/aarp.c
@@ -147,7 +147,7 @@ aarptimer(void *ignored)
  * unlocked variant returns a reference that the caller must dispose of.
  */
 struct at_ifaddr *
-at_ifawithnet_locked(struct sockaddr_at  *sat)
+at_ifawithnet_locked(const struct sockaddr_at  *sat)
 {
 	struct at_ifaddr *aa;
 	struct sockaddr_at *sat2;
@@ -167,7 +167,7 @@ at_ifawithnet_locked(struct sockaddr_at  *sat)
 }
 
 struct at_ifaddr *
-at_ifawithnet(struct sockaddr_at *sat)
+at_ifawithnet(const struct sockaddr_at *sat)
 {
 	struct at_ifaddr *aa;
 
@@ -180,7 +180,7 @@ at_ifawithnet(struct sockaddr_at *sat)
 }
 
 static void
-aarpwhohas(struct ifnet *ifp, struct sockaddr_at *sat)
+aarpwhohas(struct ifnet *ifp, const struct sockaddr_at *sat)
 {
 	struct mbuf *m;
 	struct ether_header *eh;
@@ -267,8 +267,8 @@ aarpwhohas(struct ifnet *ifp, struct sockaddr_at *sat)
 }
 
 int
-aarpresolve(struct ifnet *ifp, struct mbuf *m, struct sockaddr_at *destsat,
-    u_char *desten)
+aarpresolve(struct ifnet *ifp, struct mbuf *m,
+    const struct sockaddr_at *destsat, u_char *desten)
 {
 	struct at_ifaddr *aa;
 	struct aarptab *aat;
@@ -567,7 +567,7 @@ aarptfree(struct aarptab *aat)
 }
 
 struct aarptab *
-aarptnew(struct at_addr *addr)
+aarptnew(const struct at_addr *addr)
 {
 	int n;
 	int oldest = -1;
diff --git a/sys/netatalk/aarp.h b/sys/netatalk/aarp.h
index b55a9a7cc66c..f290c2338149 100644
--- a/sys/netatalk/aarp.h
+++ b/sys/netatalk/aarp.h
@@ -80,7 +80,7 @@ struct aarptab {
 #define	AARPOP_PROBE	0x03
 
 #ifdef _KERNEL
-struct aarptab		*aarptnew(struct at_addr      *);
+struct aarptab		*aarptnew(const struct at_addr *);
 #endif
 
 #endif /* _NETATALK_AARP_H_ */
diff --git a/sys/netatalk/at_control.c b/sys/netatalk/at_control.c
index cf470da82599..9d92a05a3cf8 100644
--- a/sys/netatalk/at_control.c
+++ b/sys/netatalk/at_control.c
@@ -721,7 +721,7 @@ at_ifinit(struct ifnet *ifp, struct at_ifaddr *aa, struct sockaddr_at *sat)
  * check whether a given address is a broadcast address for us..
  */
 int
-at_broadcast(struct sockaddr_at *sat)
+at_broadcast(const struct sockaddr_at *sat)
 {
 	struct at_ifaddr *aa;
 
diff --git a/sys/netatalk/at_extern.h b/sys/netatalk/at_extern.h
index c00e526d2343..15c785829003 100644
--- a/sys/netatalk/at_extern.h
+++ b/sys/netatalk/at_extern.h
@@ -46,16 +46,16 @@ struct socket;
 void		 aarpintr(struct mbuf *);
 void		 aarpprobe(void *arg);
 int		 aarpresolve(struct ifnet *, struct mbuf *,
-		    struct sockaddr_at *, u_char *);
+		    const struct sockaddr_at *, u_char *);
 void		 aarp_clean(void);
 void		 at1intr(struct mbuf *);
 void		 at2intr(struct mbuf *);
-int		 at_broadcast(struct sockaddr_at  *);
+int		 at_broadcast(const struct sockaddr_at  *);
 u_short		 at_cksum(struct mbuf *m, int skip);
 int		 at_control(struct socket *so, u_long cmd, caddr_t data,
 		    struct ifnet *ifp, struct thread *td);
-struct at_ifaddr	*at_ifawithnet(struct sockaddr_at *);
-struct at_ifaddr	*at_ifawithnet_locked(struct sockaddr_at  *sat);
+struct at_ifaddr	*at_ifawithnet(const struct sockaddr_at *);
+struct at_ifaddr	*at_ifawithnet_locked(const struct sockaddr_at  *sat);
 
 int		 at_inithead(void**, int);
 void		 ddp_init(void);
diff --git a/sys/netgraph/ng_fec.c b/sys/netgraph/ng_fec.c
index 459931a32cb6..b7c1f5671804 100644
--- a/sys/netgraph/ng_fec.c
+++ b/sys/netgraph/ng_fec.c
@@ -165,7 +165,7 @@ struct ng_fec_bundle {
 	int			fec_btype;
 	int			(*fec_if_output) (struct ifnet *,
 						  struct mbuf *,
-						  struct sockaddr *,
+						  const struct sockaddr *,
 						  struct route *);
 };
 
@@ -198,7 +198,7 @@ static int	ng_fec_ifmedia_upd(struct ifnet *ifp);
 static void	ng_fec_ifmedia_sts(struct ifnet *ifp, struct ifmediareq *ifmr);
 static int	ng_fec_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
 static int	ng_fec_output(struct ifnet *ifp, struct mbuf *m0,
-			struct sockaddr *dst, struct route *ro);
+			const struct sockaddr *dst, struct route *ro);
 static void	ng_fec_tick(void *arg);
 static int	ng_fec_addport(struct ng_fec_private *priv, char *iface);
 static int	ng_fec_delport(struct ng_fec_private *priv, char *iface);
@@ -923,7 +923,7 @@ ng_fec_input(struct ifnet *ifp, struct mbuf *m0)
 
 static int
 ng_fec_output(struct ifnet *ifp, struct mbuf *m,
-		struct sockaddr *dst, struct route *ro)
+	const struct sockaddr *dst, struct route *ro)
 {
 	const priv_p priv = (priv_p) ifp->if_softc;
 	struct ng_fec_bundle *b;
diff --git a/sys/netgraph/ng_iface.c b/sys/netgraph/ng_iface.c
index 5e6f12fb4b5d..e6ac5085368d 100644
--- a/sys/netgraph/ng_iface.c
+++ b/sys/netgraph/ng_iface.c
@@ -123,7 +123,7 @@ typedef struct ng_iface_private *priv_p;
 static void	ng_iface_start(struct ifnet *ifp);
 static int	ng_iface_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
 static int	ng_iface_output(struct ifnet *ifp, struct mbuf *m0,
-    			struct sockaddr *dst, struct route *ro);
+    			const struct sockaddr *dst, struct route *ro);
 static void	ng_iface_bpftap(struct ifnet *ifp,
 			struct mbuf *m, sa_family_t family);
 static int	ng_iface_send(struct ifnet *ifp, struct mbuf *m,
@@ -353,7 +353,7 @@ ng_iface_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
 
 static int
 ng_iface_output(struct ifnet *ifp, struct mbuf *m,
-    		struct sockaddr *dst, struct route *ro)
+	const struct sockaddr *dst, struct route *ro)
 {
 	struct m_tag *mtag;
 	uint32_t af;
@@ -385,13 +385,13 @@ ng_iface_output(struct ifnet *ifp, struct mbuf *m,
 	m_tag_prepend(m, mtag);
 
 	/* BPF writes need to be handled specially. */
-	if (dst->sa_family == AF_UNSPEC) {
+	if (dst->sa_family == AF_UNSPEC)
 		bcopy(dst->sa_data, &af, sizeof(af));
-		dst->sa_family = af;
-	}
+	else
+		af = dst->sa_family;
 
 	/* Berkeley packet filter */
-	ng_iface_bpftap(ifp, m, dst->sa_family);
+	ng_iface_bpftap(ifp, m, af);
 
 	if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
 		M_PREPEND(m, sizeof(sa_family_t), M_NOWAIT);
@@ -402,10 +402,10 @@ ng_iface_output(struct ifnet *ifp, struct mbuf *m,
 			ifp->if_oerrors++;
 			return (ENOBUFS);
 		}
-		*(sa_family_t *)m->m_data = dst->sa_family;
+		*(sa_family_t *)m->m_data = af;
 		error = (ifp->if_transmit)(ifp, m);
 	} else
-		error = ng_iface_send(ifp, m, dst->sa_family);
+		error = ng_iface_send(ifp, m, af);
 
 	return (error);
 }
diff --git a/sys/netinet/if_atm.c b/sys/netinet/if_atm.c
index c46460e11bc3..4816678ed2ff 100644
--- a/sys/netinet/if_atm.c
+++ b/sys/netinet/if_atm.c
@@ -317,7 +317,7 @@ atm_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info)
  *   but this is enough for PVCs entered via the "route" command.
  */
 int
-atmresolve(struct rtentry *rt, struct mbuf *m, struct sockaddr *dst,
+atmresolve(struct rtentry *rt, struct mbuf *m, const struct sockaddr *dst,
     struct atm_pseudohdr *desten)
 {
 	struct sockaddr_dl *sdl;
@@ -329,7 +329,8 @@ atmresolve(struct rtentry *rt, struct mbuf *m, struct sockaddr *dst,
 	}
 
 	if (rt == NULL) {
-		rt = RTALLOC1(dst, 0); /* link level on table 0 XXX MRT */
+		/* link level on table 0 XXX MRT */
+		rt = RTALLOC1(__DECONST(struct sockaddr *, dst), 0);
 		if (rt == NULL)
 			goto bad;	/* failed */
 		RT_REMREF(rt);		/* don't keep LL references */
diff --git a/sys/netinet/if_atm.h b/sys/netinet/if_atm.h
index bd8b51437ecc..04ad218d82c3 100644
--- a/sys/netinet/if_atm.h
+++ b/sys/netinet/if_atm.h
@@ -43,5 +43,5 @@ struct rtentry;
 struct sockaddr;
 
 void atm_rtrequest(int, struct rtentry *, struct rt_addrinfo *);
-int atmresolve(struct rtentry *, struct mbuf *, struct sockaddr *,
+int atmresolve(struct rtentry *, struct mbuf *, const struct sockaddr *,
 		struct atm_pseudohdr *);
diff --git a/sys/netinet/if_ether.c b/sys/netinet/if_ether.c
index 7031784fc85a..9ba356c1655a 100644
--- a/sys/netinet/if_ether.c
+++ b/sys/netinet/if_ether.c
@@ -73,7 +73,7 @@ __FBSDID("$FreeBSD$");
 
 #include <security/mac/mac_framework.h>
 
-#define SIN(s) ((struct sockaddr_in *)s)
+#define SIN(s) ((const struct sockaddr_in *)(s))
 #define SDL(s) ((struct sockaddr_dl *)s)
 
 SYSCTL_DECL(_net_link_ether);
@@ -215,8 +215,8 @@ arptimer(void *arg)
  *	- arp header source ethernet address
  */
 void
-arprequest(struct ifnet *ifp, struct in_addr *sip, struct in_addr  *tip,
-    u_char *enaddr)
+arprequest(struct ifnet *ifp, const struct in_addr *sip,
+    const struct in_addr *tip, u_char *enaddr)
 {
 	struct mbuf *m;
 	struct arphdr *ah;
@@ -272,9 +272,9 @@ arprequest(struct ifnet *ifp, struct in_addr *sip, struct in_addr  *tip,
 	ah->ar_hln = ifp->if_addrlen;		/* hardware address length */
 	ah->ar_pln = sizeof(struct in_addr);	/* protocol address length */
 	ah->ar_op = htons(ARPOP_REQUEST);
-	bcopy((caddr_t)enaddr, (caddr_t)ar_sha(ah), ah->ar_hln);
-	bcopy((caddr_t)sip, (caddr_t)ar_spa(ah), ah->ar_pln);
-	bcopy((caddr_t)tip, (caddr_t)ar_tpa(ah), ah->ar_pln);
+	bcopy(enaddr, ar_sha(ah), ah->ar_hln);
+	bcopy(sip, ar_spa(ah), ah->ar_pln);
+	bcopy(tip, ar_tpa(ah), ah->ar_pln);
 	sa.sa_family = AF_ARP;
 	sa.sa_len = 2;
 	m->m_flags |= M_BCAST;
@@ -298,7 +298,7 @@ arprequest(struct ifnet *ifp, struct in_addr *sip, struct in_addr  *tip,
  */
 int
 arpresolve(struct ifnet *ifp, struct rtentry *rt0, struct mbuf *m,
-	struct sockaddr *dst, u_char *desten, struct llentry **lle)
+	const struct sockaddr *dst, u_char *desten, struct llentry **lle)
 {
 	struct llentry *la = 0;
 	u_int flags = 0;
diff --git a/sys/netinet/if_ether.h b/sys/netinet/if_ether.h
index 6b47912381f1..fbd0a1ac4e9e 100644
--- a/sys/netinet/if_ether.h
+++ b/sys/netinet/if_ether.h
@@ -48,9 +48,9 @@
 	(enaddr)[0] = 0x01; \
 	(enaddr)[1] = 0x00; \
 	(enaddr)[2] = 0x5e; \
-	(enaddr)[3] = ((u_char *)ipaddr)[1] & 0x7f; \
-	(enaddr)[4] = ((u_char *)ipaddr)[2]; \
-	(enaddr)[5] = ((u_char *)ipaddr)[3]; \
+	(enaddr)[3] = ((const u_char *)ipaddr)[1] & 0x7f; \
+	(enaddr)[4] = ((const u_char *)ipaddr)[2]; \
+	(enaddr)[5] = ((const u_char *)ipaddr)[3]; \
 }
 /*
  * Macro to map an IP6 multicast address to an Ethernet multicast address.
@@ -63,10 +63,10 @@
 {                                                                       \
 	(enaddr)[0] = 0x33;						\
 	(enaddr)[1] = 0x33;						\
-	(enaddr)[2] = ((u_char *)ip6addr)[12];				\
-	(enaddr)[3] = ((u_char *)ip6addr)[13];				\
-	(enaddr)[4] = ((u_char *)ip6addr)[14];				\
-	(enaddr)[5] = ((u_char *)ip6addr)[15];				\
+	(enaddr)[2] = ((const u_char *)ip6addr)[12];			\
+	(enaddr)[3] = ((const u_char *)ip6addr)[13];			\
+	(enaddr)[4] = ((const u_char *)ip6addr)[14];			\
+	(enaddr)[5] = ((const u_char *)ip6addr)[15];			\
 }
 
 /*
@@ -115,11 +115,10 @@ extern u_char	ether_ipmulticast_max[ETHER_ADDR_LEN];
 struct llentry;
 struct ifaddr;
 
-int	arpresolve(struct ifnet *ifp, struct rtentry *rt,
-		    struct mbuf *m, struct sockaddr *dst, u_char *desten,
-		    struct llentry **lle);
-void	arprequest(struct ifnet *, struct in_addr *, struct in_addr *,
-		    u_char *);
+int	arpresolve(struct ifnet *ifp, struct rtentry *rt, struct mbuf *m,
+	    const struct sockaddr *dst, u_char *desten, struct llentry **lle);
+void	arprequest(struct ifnet *, const struct in_addr *,
+	    const struct in_addr *, u_char *);
 void	arp_ifinit(struct ifnet *, struct ifaddr *);
 void	arp_ifinit2(struct ifnet *, struct ifaddr *, u_char *);
 void	arp_ifscrub(struct ifnet *, uint32_t);
diff --git a/sys/netinet/ip_carp.c b/sys/netinet/ip_carp.c
index eaff4f6fcad1..43c387fc129c 100644
--- a/sys/netinet/ip_carp.c
+++ b/sys/netinet/ip_carp.c
@@ -1372,7 +1372,7 @@ carp_multicast_cleanup(struct carp_if *cif, sa_family_t sa)
 }
 
 int
-carp_output(struct ifnet *ifp, struct mbuf *m, struct sockaddr *sa)
+carp_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa)
 {
 	struct m_tag *mtag;
 	struct carp_softc *sc;
diff --git a/sys/netinet/ip_carp.h b/sys/netinet/ip_carp.h
index 22b08b2400ac..de71185a0f83 100644
--- a/sys/netinet/ip_carp.h
+++ b/sys/netinet/ip_carp.h
@@ -147,7 +147,8 @@ void		carp_detach(struct ifaddr *);
 void		carp_carpdev_state(struct ifnet *);
 void		carp_input (struct mbuf *, int);
 int		carp6_input (struct mbuf **, int *, int);
-int		carp_output (struct ifnet *, struct mbuf *, struct sockaddr *);
+int		carp_output (struct ifnet *, struct mbuf *,
+		    const struct sockaddr *);
 int		carp_master(struct ifaddr *);
 int		carp_iamatch(struct ifaddr *, uint8_t **);
 struct ifaddr	*carp_iamatch6(struct ifnet *, struct in6_addr *);
@@ -166,7 +167,7 @@ extern int (*carp_master_p)(struct ifaddr *);
 extern int (*carp_forus_p)(struct ifnet *, u_char *);
 /* net/if_ethersubr.c */
 extern int (*carp_output_p)(struct ifnet *, struct mbuf *,
-    struct sockaddr *);
+    const struct sockaddr *);
 /* net/rtsock.c */
 extern int (*carp_get_vhid_p)(struct ifaddr *);
 #ifdef INET
diff --git a/sys/netinet/ip_output.c b/sys/netinet/ip_output.c
index 5770ae76d53f..21d47f791caa 100644
--- a/sys/netinet/ip_output.c
+++ b/sys/netinet/ip_output.c
@@ -622,7 +622,8 @@ ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 		 * to avoid confusing lower layers.
 		 */
 		m->m_flags &= ~(M_PROTOFLAGS);
-		error = (*ifp->if_output)(ifp, m, (struct sockaddr *)gw, ro);
+		error = (*ifp->if_output)(ifp, m,
+		    (const struct sockaddr *)gw, ro);
 		goto done;
 	}
 
@@ -656,7 +657,7 @@ ip_output(struct mbuf *m, struct mbuf *opt, struct route *ro, int flags,
 			m->m_flags &= ~(M_PROTOFLAGS);
 
 			error = (*ifp->if_output)(ifp, m,
-			    (struct sockaddr *)gw, ro);
+			    (const struct sockaddr *)gw, ro);
 		} else
 			m_freem(m);
 	}
diff --git a/sys/netinet6/nd6.c b/sys/netinet6/nd6.c
index 7dbdcb8d9f7f..0e308252814d 100644
--- a/sys/netinet6/nd6.c
+++ b/sys/netinet6/nd6.c
@@ -81,7 +81,7 @@ __FBSDID("$FreeBSD$");
 #define ND6_SLOWTIMER_INTERVAL (60 * 60) /* 1 hour */
 #define ND6_RECALC_REACHTM_INTERVAL (60 * 120) /* 2 hours */
 
-#define SIN6(s) ((struct sockaddr_in6 *)s)
+#define SIN6(s) ((const struct sockaddr_in6 *)(s))
 
 /* timer values */
 VNET_DEFINE(int, nd6_prune)	= 1;	/* walk list every 1 seconds */
@@ -2156,7 +2156,7 @@ nd6_need_cache(struct ifnet *ifp)
  */
 int
 nd6_storelladdr(struct ifnet *ifp, struct mbuf *m,
-    struct sockaddr *dst, u_char *desten, struct llentry **lle)
+    const struct sockaddr *dst, u_char *desten, struct llentry **lle)
 {
 	struct llentry *ln;
 
diff --git a/sys/netinet6/nd6.h b/sys/netinet6/nd6.h
index 94202e10a6d4..25d8c5d1f6ba 100644
--- a/sys/netinet6/nd6.h
+++ b/sys/netinet6/nd6.h
@@ -417,7 +417,7 @@ int nd6_output_flush(struct ifnet *, struct ifnet *, struct mbuf *,
 	struct sockaddr_in6 *, struct route *);
 int nd6_need_cache(struct ifnet *);
 int nd6_storelladdr(struct ifnet *, struct mbuf *,
-	struct sockaddr *, u_char *, struct llentry **);
+	const struct sockaddr *, u_char *, struct llentry **);
 
 /* nd6_nbr.c */
 void nd6_na_input(struct mbuf *, int, int);
diff --git a/sys/netpfil/ipfw/ip_fw_log.c b/sys/netpfil/ipfw/ip_fw_log.c
index 0f3ab9da9e05..0eb918b1adb4 100644
--- a/sys/netpfil/ipfw/ip_fw_log.c
+++ b/sys/netpfil/ipfw/ip_fw_log.c
@@ -113,7 +113,7 @@ log_dummy(struct ifnet *ifp, u_long cmd, caddr_t addr)
 
 static int
 ipfw_log_output(struct ifnet *ifp, struct mbuf *m,
-	struct sockaddr *dst, struct route *ro)
+	const struct sockaddr *dst, struct route *ro)
 {
 	if (m != NULL)
 		FREE_PKT(m);
diff --git a/sys/netpfil/pf/if_pflog.c b/sys/netpfil/pf/if_pflog.c
index b9e716bb42fb..1efd5e2b4fe6 100644
--- a/sys/netpfil/pf/if_pflog.c
+++ b/sys/netpfil/pf/if_pflog.c
@@ -82,8 +82,8 @@ __FBSDID("$FreeBSD$");
 #define DPRINTF(x)
 #endif
 
-static int	pflogoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
-		    struct route *);
+static int	pflogoutput(struct ifnet *, struct mbuf *,
+		    const struct sockaddr *, struct route *);
 static void	pflogattach(int);
 static int	pflogioctl(struct ifnet *, u_long, caddr_t);
 static void	pflogstart(struct ifnet *);
@@ -169,7 +169,7 @@ pflogstart(struct ifnet *ifp)
 }
 
 static int
-pflogoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+pflogoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
 	struct route *rt)
 {
 	m_freem(m);
diff --git a/sys/netpfil/pf/if_pfsync.c b/sys/netpfil/pf/if_pfsync.c
index 1ee99767393d..03276552029c 100644
--- a/sys/netpfil/pf/if_pfsync.c
+++ b/sys/netpfil/pf/if_pfsync.c
@@ -255,8 +255,8 @@ static int	pfsync_clone_create(struct if_clone *, int, caddr_t);
 static void	pfsync_clone_destroy(struct ifnet *);
 static int	pfsync_alloc_scrub_memory(struct pfsync_state_peer *,
 		    struct pf_state_peer *);
-static int	pfsyncoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
-		    struct route *);
+static int	pfsyncoutput(struct ifnet *, struct mbuf *,
+		    const struct sockaddr *, struct route *);
 static int	pfsyncioctl(struct ifnet *, u_long, caddr_t);
 
 static int	pfsync_defer(struct pf_state *, struct mbuf *);
@@ -1247,7 +1247,7 @@ pfsync_in_error(struct pfsync_pkt *pkt, struct mbuf *m, int offset, int count)
 }
 
 static int
-pfsyncoutput(struct ifnet *ifp, struct mbuf *m, struct sockaddr *dst,
+pfsyncoutput(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *dst,
 	struct route *rt)
 {
 	m_freem(m);