 @@ -1,14 +1,14 @@
-/*	$NetBSD: if_arp.c,v 1.229 2016/10/11 12:32:30 roy Exp $	*/
+/*	$NetBSD: if_arp.c,v 1.230 2016/10/11 13:59:30 roy Exp $	*/
 /*-
  * Copyright (c) 1998, 2000, 2008 The NetBSD Foundation, Inc.
  * All rights reserved.
+ *
  * This code is derived from software contributed to The NetBSD Foundation
  * by Public Access Networks Corporation ("Panix").  It was developed under
  * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
 @@ -58,27 +58,27 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
+ *
  *	@(#)if_ether.c	8.2 (Berkeley) 9/26/94
  */
 /*
  * Ethernet address resolution protocol.
  * TODO:
  *	add "inuse/lock" bit (or ref. count) along with valid bit
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.229 2016/10/11 12:32:30 roy Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.230 2016/10/11 13:59:30 roy Exp $");
 #ifdef _KERNEL_OPT
 #include "opt_ddb.h"
 #include "opt_inet.h"
 #endif
 #ifdef INET
 #include "arp.h"
 #include "bridge.h"
 #include <sys/param.h>
 #include <sys/systm.h>
 @@ -168,27 +168,27 @@ static	void arp_settimer(struct llentry
 static	struct llentry *arplookup(struct ifnet *, struct mbuf *,
 	    const struct in_addr *, const struct sockaddr *, int);
 static	struct llentry *arpcreate(struct ifnet *, struct mbuf *,
 	    const struct in_addr *, const struct sockaddr *, int);
 static	void in_arpinput(struct mbuf *);
 static	void in_revarpinput(struct mbuf *);
 static	void revarprequest(struct ifnet *);
 static	void arp_drainstub(void);
 static void arp_dad_timer(struct ifaddr *);
 static void arp_dad_start(struct ifaddr *);
 static void arp_dad_stop(struct ifaddr *);
-static void arp_dad_duplicated(struct ifaddr *);
+static void arp_dad_duplicated(struct ifaddr *, const char *);
 static void arp_init_llentry(struct ifnet *, struct llentry *);
 #if NTOKEN > 0
 static void arp_free_llentry_tokenring(struct llentry *);
 #endif
 struct	ifqueue arpintrq = {
 	.ifq_head = NULL,
 	.ifq_tail = NULL,
 	.ifq_len = 0,
 	.ifq_maxlen = 50,
 	.ifq_drops = 0,
 };
 @@ -1123,57 +1123,46 @@ in_arpinput(struct mbuf *m)
+	}
 	/*
 	 * If the source IP address is zero, this is an RFC 5227 ARP probe
 	 */
 	if (in_nullhost(isaddr))
 		ARP_STATINC(ARP_STAT_RCVZEROSPA);
 	else if (in_hosteq(isaddr, myaddr))
 		ARP_STATINC(ARP_STAT_RCVLOCALSPA);
 	if (in_nullhost(itaddr))
 		ARP_STATINC(ARP_STAT_RCVZEROTPA);
-	/* DAD check, RFC 5227 2.1.1, Probe Details */
+	/* DAD check, RFC 5227 */
 	if (in_hosteq(isaddr, myaddr) ||
 	    (in_nullhost(isaddr) && in_hosteq(itaddr, myaddr)))
+	{
-		/* If our address is tentative, mark it as duplicated */
+		arp_dad_duplicated((struct ifaddr *)ia,
-		if (ia->ia4_flags & IN_IFF_TENTATIVE)
+		    lla_snprintf(ar_sha(ah), ah->ar_hln));
-			arp_dad_duplicated((struct ifaddr *)ia);
+		goto out;
 		/* If our address is unuseable, don't reply */
 		if (ia->ia4_flags & (IN_IFF_NOTREADY | IN_IFF_DETACHED))
 			goto out;
+	}
 	/*
 	 * If the target IP address is zero, ignore the packet.
 	 * This prevents the code below from tring to answer
 	 * when we are using IP address zero (booting).
 	 */
 	if (in_nullhost(itaddr))
 		goto out;
 	if (in_nullhost(isaddr))
 		goto reply;
 	if (in_hosteq(isaddr, myaddr)) {
 		log(LOG_ERR,
 		   "duplicate IP address %s sent from link address %s\n",
 		   in_fmtaddr(isaddr), lla_snprintf(ar_sha(ah), ah->ar_hln));
 		itaddr = myaddr;
 		goto reply;
 	if (in_hosteq(itaddr, myaddr))
 		la = arpcreate(ifp, m, &isaddr, NULL, 1);
 	else
 		la = arplookup(ifp, m, &isaddr, NULL, 1);
 	if (la == NULL)
 		goto reply;
 	if ((la->la_flags & LLE_VALID) &&
 	    memcmp(ar_sha(ah), &la->ll_addr, ifp->if_addrlen)) {
 		if (la->la_flags & LLE_STATIC) {
 			ARP_STATINC(ARP_STAT_RCVOVERPERM);
 			if (!log_permanent_modify)
 				goto out;
 @@ -1764,61 +1753,65 @@ announce:
 	TAILQ_REMOVE(&dadq, dp, dad_list);
 	free(dp, M_IPARP);
 	dp = NULL;
 	ifafree(ifa);
 done:
 	mutex_exit(&arp_dad_lock);
 	KERNEL_UNLOCK_ONE(NULL);
 	mutex_exit(softnet_lock);
+}
 static void
-arp_dad_duplicated(struct ifaddr *ifa)
+arp_dad_duplicated(struct ifaddr *ifa, const char *sha)
+{
 	struct in_ifaddr *ia = (struct in_ifaddr *)ifa;
-	struct ifnet *ifp;
+	struct ifnet *ifp = ifa->ifa_ifp;
-	struct dadq *dp;
+	const char *iastr = in_fmtaddr(ia->ia_addr.sin_addr);
-	mutex_enter(&arp_dad_lock);
+	if (ia->ia4_flags & (IN_IFF_TENTATIVE|IN_IFF_DUPLICATED)) {
-	dp = arp_dad_find(ifa);
+		log(LOG_ERR,
-	if (dp == NULL) {
+		    "%s: DAD duplicate address %s from %s\n",
-		mutex_exit(&arp_dad_lock);
+		    if_name(ifp), iastr, sha);
-		/* DAD seems to be stopping, so do nothing. */
+	} else if (ia->ia_dad_defended == 0 ||
 		   ia->ia_dad_defended < time_uptime - DEFEND_INTERVAL) {
 		ia->ia_dad_defended = time_uptime;
 		arpannounce1(ifa);
 		log(LOG_ERR,
 		    "%s: DAD defended address %s from %s\n",
 		    if_name(ifp), iastr, sha);
 		return;
 	} else {
 		/* If DAD is disabled, just report the duplicate. */
 		if (ip_dad_count == 0) {
 			log(LOG_ERR,
 			    "%s: DAD ignoring duplicate address %s from %s\n",
 			    if_name(ifp), iastr, sha);
 			return;
+		}
 		log(LOG_ERR,
 		    "%s: DAD defence failed for %s from %s\n",
 		    if_name(ifp), iastr, sha);
+	}
-	ifp = ifa->ifa_ifp;
+	arp_dad_stop(ifa);
 	log(LOG_ERR,
 	    "%s: DAD detected duplicate IPv4 address %s: ARP out=%d\n",
 	    if_name(ifp), in_fmtaddr(ia->ia_addr.sin_addr),
 	    dp->dad_arp_ocount);
 	ia->ia4_flags &= ~IN_IFF_TENTATIVE;
-	ia->ia4_flags |= IN_IFF_DUPLICATED;
+	if ((ia->ia4_flags & IN_IFF_DUPLICATED) == 0) {
 		ia->ia4_flags |= IN_IFF_DUPLICATED;
-	/* We are done with DAD, with duplicated address found. (failure) */
+		/* Inform the routing socket of the duplicate address */
-	arp_dad_stoptimer(dp);
+		rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
+	}
 	/* Inform the routing socket that DAD has completed */
 	rt_newaddrmsg(RTM_NEWADDR, ifa, 0, NULL);
 	TAILQ_REMOVE(&dadq, dp, dad_list);
 	mutex_exit(&arp_dad_lock);
 	free(dp, M_IPARP);
 	dp = NULL;
 	ifafree(ifa);
+}
 /*
  * Called from 10 Mb/s Ethernet interrupt handlers
  * when ether packet type ETHERTYPE_REVARP
  * is received.  Common length and type checks are done here,
  * then the protocol-specific routine is called.
  */
 void
 revarpinput(struct mbuf *m)
+{
 	struct arphdr *ar;

 @@ -1,14 +1,14 @@
-/*	$NetBSD: in_var.h,v 1.87 2016/09/29 15:18:18 roy Exp $	*/
+/*	$NetBSD: in_var.h,v 1.88 2016/10/11 13:59:30 roy Exp $	*/
 /*-
  * Copyright (c) 1998 The NetBSD Foundation, Inc.
  * All rights reserved.
+ *
  * This code is derived from software contributed to The NetBSD Foundation
  * by Public Access Networks Corporation ("Panix").  It was developed under
  * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
 @@ -97,26 +97,27 @@ struct in_ifaddr {
 	LIST_ENTRY(in_ifaddr) ia_hash;	/* entry in bucket of inet addresses */
 	TAILQ_ENTRY(in_ifaddr) ia_list;	/* list of internet addresses */
 	struct	sockaddr_in ia_addr;	/* reserve space for interface name */
 	struct	sockaddr_in ia_dstaddr;	/* reserve space for broadcast addr */
 #define	ia_broadaddr	ia_dstaddr
 	struct	sockaddr_in ia_sockmask; /* reserve space for general netmask */
 	LIST_HEAD(, in_multi) ia_multiaddrs; /* list of multicast addresses */
 	struct	in_multi *ia_allhosts;	/* multicast address record for
 					   the allhosts multicast group */
 	uint16_t ia_idsalt;		/* ip_id salt for this ia */
 	int	ia4_flags;		/* address flags */
 	void	(*ia_dad_start) (struct ifaddr *);	/* DAD start function */
 	void	(*ia_dad_stop) (struct ifaddr *);	/* DAD stop function */
 	time_t	ia_dad_defended;	/* last time of DAD defence */
 #ifdef _KERNEL
 	struct pslist_entry	ia_hash_pslist_entry;
 	struct pslist_entry	ia_pslist_entry;
 #endif
 };
 #ifdef _KERNEL
 static inline void
 ia4_acquire(struct in_ifaddr *ia, struct psref *psref)
+{
 	KASSERT(ia != NULL);