From: Roy Marples <roy@marples.name>
Date: Fri, 6 Sep 2013 09:38:24 +0000 (+0000)
Subject: It seems that FreeBSD will send RTM_DELADDR + RTM_NEWADDR when
X-Git-Tag: v6.1.0~24
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=27f61373d14c2e44b06f6f2ce26baf899ad8c283;p=thirdparty%2Fdhcpcd.git

It seems that FreeBSD will send RTM_DELADDR + RTM_NEWADDR when
replacing an existing IPv4 address with the same values.
As such, we need to maintain a list of configured IPv4 addresses
for each interface so we know when to add it and when to skip it
to avoid receiving bogus RTM_DELADDR messages from ourself.
---

diff --git a/dhcp.c b/dhcp.c
index 30c1ecd6..b13778c2 100644
--- a/dhcp.c
+++ b/dhcp.c
@@ -1699,7 +1699,6 @@ dhcp_rebind(void *arg)
 	send_rebind(ifp);
 }
 
-
 void
 dhcp_bind(void *arg)
 {
@@ -1721,10 +1720,10 @@ dhcp_bind(void *arg)
 	state->offer = NULL;
 	get_lease(lease, state->new);
 	if (ifo->options & DHCPCD_STATIC) {
-		syslog(LOG_INFO, "%s: using static address %s",
-		    iface->name, inet_ntoa(lease->addr));
+		syslog(LOG_INFO, "%s: using static address %s/%d",
+		    iface->name, inet_ntoa(lease->addr),
+		    inet_ntocidr(lease->net));
 		lease->leasetime = ~0U;
-		lease->net.s_addr = ifo->req_mask.s_addr;
 		state->reason = "STATIC";
 	} else if (state->new->cookie != htonl(MAGIC_COOKIE)) {
 		syslog(LOG_INFO, "%s: using IPv4LL address %s",
@@ -1831,7 +1830,7 @@ dhcp_timeout(void *arg)
 }
 
 struct dhcp_message *
-dhcp_message_new(struct in_addr *addr, struct in_addr *mask)
+dhcp_message_new(const struct in_addr *addr, const struct in_addr *mask)
 {
 	struct dhcp_message *dhcp;
 	uint8_t *p;
@@ -1851,60 +1850,65 @@ dhcp_message_new(struct in_addr *addr, struct in_addr *mask)
 	return dhcp;
 }
 
-static int
-handle_3rdparty(struct interface *ifp)
+static void
+dhcp_static(struct interface *ifp)
 {
 	struct if_options *ifo;
 	struct dhcp_state *state;
-	struct in_addr addr, net, dst;
 
+	state = D_STATE(ifp);
 	ifo = ifp->options;
-	if (ifo->req_addr.s_addr != INADDR_ANY)
-		return 0;
-
-	if (ipv4_getaddress(ifp->name, &addr, &net, &dst) == 1)
-		ipv4_handleifa(RTM_NEWADDR, ifp->name, &addr, &net, &dst);
-	else {
+	if (ifo->req_addr.s_addr == INADDR_ANY) {
 		syslog(LOG_INFO,
-		    "%s: waiting for 3rd party to configure IP address",
+		    "%s: waiting for 3rd party to "
+		    "configure IP address",
 		    ifp->name);
-		state = D_STATE(ifp);
 		state->reason = "3RDPARTY";
 		script_runreason(ifp, state->reason);
-	}
-	return 1;
-}
-
-static void
-dhcp_static(struct interface *ifp)
-{
-	struct if_options *ifo;
-	struct dhcp_state *state;
-
-	if (handle_3rdparty(ifp))
 		return;
-	ifo = ifp->options;
-	state = D_STATE(ifp);
+	}
 	state->offer = dhcp_message_new(&ifo->req_addr, &ifo->req_mask);
-	eloop_timeout_delete(NULL, ifp);
-	dhcp_bind(ifp);
+	if (state->offer) {
+		eloop_timeout_delete(NULL, ifp);
+		dhcp_bind(ifp);
+	}
 }
 
 void
 dhcp_inform(struct interface *ifp)
 {
 	struct dhcp_state *state;
-
-	if (handle_3rdparty(ifp))
-		return;
+	struct if_options *ifo;
+	struct ipv4_addr *ap;
 
 	state = D_STATE(ifp);
+	ifo = ifp->options;
 	if (options & DHCPCD_TEST) {
-		state->addr.s_addr = ifp->options->req_addr.s_addr;
-		state->net.s_addr = ifp->options->req_mask.s_addr;
+		state->addr.s_addr = ifo->req_addr.s_addr;
+		state->net.s_addr = ifo->req_mask.s_addr;
 	} else {
-		ifp->options->options |= DHCPCD_STATIC;
-		dhcp_static(ifp);
+		if (ifo->req_addr.s_addr == INADDR_ANY) {
+			state = D_STATE(ifp);
+			ap = ipv4_findaddr(ifp, NULL, NULL);
+			if (ap == NULL) {
+				syslog(LOG_INFO,
+					"%s: waiting for 3rd party to "
+					"configure IP address",
+					ifp->name);
+				state->reason = "3RDPARTY";
+				script_runreason(ifp, state->reason);
+				return;
+			}
+			state->offer =
+			    dhcp_message_new(&ap->addr, &ap->net);
+		} else 
+			state->offer =
+			    dhcp_message_new(&ifo->req_addr, &ifo->req_mask);
+		if (state->offer) {
+			ifo->options |= DHCPCD_STATIC;
+			dhcp_bind(ifp);
+			ifo->options &= ~DHCPCD_STATIC;
+		}
 	}
 
 	state->state = DHS_INFORM;
@@ -2217,6 +2221,8 @@ dhcp_handle(struct interface *iface, struct dhcp_message **dhcpp,
 
 		if (!(ifo->options & DHCPCD_INFORM))
 			log_dhcp(LOG_DEBUG, "acknowledged", iface, dhcp, from);
+		else
+		    ifo->options &= ~DHCPCD_STATIC;
 	}
 
 	/* BOOTP could have already assigned this above, so check we still
@@ -2241,7 +2247,7 @@ dhcp_handle(struct interface *iface, struct dhcp_message **dhcpp,
 		/* If the interface already has the address configured
 		 * then we can't ARP for duplicate detection. */
 		addr.s_addr = state->offer->yiaddr;
-		if (ipv4_hasaddress(iface->name, &addr, NULL) != 1) {
+		if (!ipv4_findaddr(iface, &addr, NULL)) {
 			state->claims = 0;
 			state->probes = 0;
 			state->conflicts = 0;
@@ -2684,3 +2690,65 @@ dhcp_start(struct interface *ifp)
 	else
 		dhcp_reboot(ifp);
 }
+
+void
+dhcp_handleifa(int type, struct interface *ifp,
+	const struct in_addr *addr,
+	const struct in_addr *net,
+	const struct in_addr *dst)
+{
+	struct dhcp_state *state;
+	struct if_options *ifo;
+	int i;
+
+	state = D_STATE(ifp);
+	if (state == NULL)
+		return;
+
+	if (type == RTM_DELADDR) {
+		if (state->new &&
+		    state->new->yiaddr == addr->s_addr)
+			syslog(LOG_INFO, "%s: removing IP address %s/%d",
+			    ifp->name, inet_ntoa(state->lease.addr),
+			    inet_ntocidr(state->lease.net));
+		return;
+	}
+
+	if (type != RTM_NEWADDR)
+		return;
+
+	ifo = ifp->options;
+	if (ifo->options & DHCPCD_INFORM) {
+		if (state->state != DHS_INFORM)
+			dhcp_inform(ifp);
+		return;
+	}
+
+	if (!(ifo->options & DHCPCD_STATIC))
+		return;
+	if (ifo->req_addr.s_addr != INADDR_ANY)
+		return;
+
+	free(state->old);
+	state->old = state->new;
+	state->new = dhcp_message_new(addr, net);
+	if (state->new == NULL)
+		return;
+	state->dst.s_addr = dst ? dst->s_addr : INADDR_ANY;
+	if (dst) {
+		for (i = 1; i < 255; i++)
+			if (i != DHO_ROUTER && has_option_mask(ifo->dstmask,i))
+				dhcp_message_add_addr(state->new, i, *dst);
+	}
+	state->reason = "STATIC";
+	ipv4_buildroutes();
+	script_runreason(ifp, state->reason);
+	if (ifo->options & DHCPCD_INFORM) {
+		state->state = DHS_INFORM;
+		state->xid = dhcp_xid(ifp);
+		state->lease.server.s_addr = dst ? dst->s_addr : INADDR_ANY;
+		state->addr = *addr;
+		state->net = *net;
+		dhcp_inform(ifp);
+	}
+}
diff --git a/dhcp.h b/dhcp.h
index 60586988..986fd98a 100644
--- a/dhcp.h
+++ b/dhcp.h
@@ -259,8 +259,8 @@ ssize_t dhcp_env(char **, const char *, const struct dhcp_message *,
     const struct interface *);
 
 uint32_t dhcp_xid(const struct interface *);
-struct dhcp_message *dhcp_message_new(struct in_addr *addr,
-    struct in_addr *mask);
+struct dhcp_message *dhcp_message_new(const struct in_addr *addr,
+    const struct in_addr *mask);
 int dhcp_message_add_addr(struct dhcp_message *, uint8_t, struct in_addr);
 ssize_t make_message(struct dhcp_message **, const struct interface *,
     uint8_t);
@@ -270,6 +270,9 @@ ssize_t write_lease(const struct interface *, const struct dhcp_message *);
 struct dhcp_message *read_lease(const struct interface *);
 void get_lease(struct dhcp_lease *, const struct dhcp_message *);
 
+void dhcp_handleifa(int, struct interface *,
+    const struct in_addr *, const struct in_addr *, const struct in_addr *);
+
 void dhcp_drop(struct interface *, const char *);
 void dhcp_start(struct interface *);
 void dhcp_stop(struct interface *);
diff --git a/dhcpcd.h b/dhcpcd.h
index a55cef7c..4f0f56f5 100644
--- a/dhcpcd.h
+++ b/dhcpcd.h
@@ -43,11 +43,12 @@
 #define LINK_UNKNOWN	0
 #define LINK_DOWN	-1
 
-#define IF_DATA_DHCP	0
-#define IF_DATA_IPV6	1
-#define IF_DATA_IPV6ND	2
-#define IF_DATA_DHCP6	3
-#define IF_DATA_MAX	4
+#define IF_DATA_IPV4	0
+#define IF_DATA_DHCP	1	
+#define IF_DATA_IPV6	2
+#define IF_DATA_IPV6ND	3
+#define IF_DATA_DHCP6	4
+#define IF_DATA_MAX	5
 
 struct interface {
 	TAILQ_ENTRY(interface) next;
diff --git a/if-bsd.c b/if-bsd.c
index ba607e3b..d7e466f8 100644
--- a/if-bsd.c
+++ b/if-bsd.c
@@ -659,7 +659,8 @@ manage_link(int fd)
 					COPYOUT(rt.dest, rti_info[RTAX_IFA]);
 					COPYOUT(rt.net, rti_info[RTAX_NETMASK]);
 					COPYOUT(rt.gate, rti_info[RTAX_BRD]);
-					ipv4_handleifa(rtm->rtm_type, ifname,
+					ipv4_handleifa(rtm->rtm_type,
+					    NULL, ifname,
 					    &rt.dest, &rt.net, &rt.gate);
 					break;
 #endif
diff --git a/if-options.h b/if-options.h
index a3ef0514..69c7200a 100644
--- a/if-options.h
+++ b/if-options.h
@@ -36,8 +36,6 @@
 #include <limits.h>
 #include <stdint.h>
 
-#include "ipv4.h"
-
 /* Don't set any optional arguments here so we retain POSIX
  * compatibility with getopt */
 #define IF_OPTS "46bc:de:f:gh:i:kl:m:no:pqr:s:t:u:v:wxy:z:ABC:DEF:GHI:JKLO:Q:S:TUVW:X:Z:"
diff --git a/ipv4.c b/ipv4.c
index bd33ad6b..06dc761a 100644
--- a/ipv4.c
+++ b/ipv4.c
@@ -25,6 +25,7 @@
  * SUCH DAMAGE.
  */
 
+#include <sys/queue.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 
@@ -47,6 +48,7 @@
 
 #include "config.h"
 #include "common.h"
+#include "dhcpcd.h"
 #include "dhcp.h"
 #include "if-options.h"
 #include "if-pref.h"
@@ -109,74 +111,45 @@ ipv4_getnetmask(uint32_t addr)
 	return 0;
 }
 
+struct ipv4_addr *
+ipv4_findaddr(struct interface *ifp,
+    const struct in_addr *addr, const struct in_addr *net)
+{
+	struct ipv4_state *state;
+	struct ipv4_addr *ap;
+
+	state = IPV4_STATE(ifp);
+	if (state) {
+		TAILQ_FOREACH(ap, &state->addrs, next) {
+			if ((addr == NULL || ap->addr.s_addr == addr->s_addr) &&
+			    (net == NULL || ap->net.s_addr == net->s_addr))
+				return ap;
+		}
+	}
+	return NULL;
+}
+
 int
 ipv4_addrexists(const struct in_addr *addr)
 {
-	const struct interface *ifp;
-	const struct dhcp_state *state;
+	struct interface *ifp;
+	struct dhcp_state *state;
 
 	TAILQ_FOREACH(ifp, ifaces, next) {
-		state = D_CSTATE(ifp);
+		state = D_STATE(ifp);
 		if (state) {
 			if (addr == NULL) {
-				if (state->addr.s_addr)
+				if (state->addr.s_addr != INADDR_ANY)
 					return 1;
-			} else if (memcmp(&addr->s_addr,
-			    &state->addr.s_addr,
-			    sizeof(state->addr.s_addr)) == 0)
+			} else if (addr->s_addr == state->addr.s_addr)
 				return 1;
 		}
+		if (addr != NULL && ipv4_findaddr(ifp, addr, NULL))
+			return 1;
 	}
 	return 0;
 }
 
-int
-ipv4_doaddress(const char *ifname,
-    struct in_addr *addr, struct in_addr *net, struct in_addr *dst, int act)
-{
-	struct ifaddrs *ifaddrs, *ifa;
-	const struct sockaddr_in *a, *n, *d;
-	int retval;
-
-	if (getifaddrs(&ifaddrs) == -1)
-		return -1;
-
-	retval = 0;
-	for (ifa = ifaddrs; ifa; ifa = ifa->ifa_next) {
-		if (ifa->ifa_addr == NULL ||
-		    ifa->ifa_addr->sa_family != AF_INET ||
-		    strcmp(ifa->ifa_name, ifname) != 0)
-			continue;
-		a = (const struct sockaddr_in *)(void *)ifa->ifa_addr;
-		n = (const struct sockaddr_in *)(void *)ifa->ifa_netmask;
-		if (ifa->ifa_flags & IFF_POINTOPOINT)
-			d = (const struct sockaddr_in *)(void *)
-			    ifa->ifa_dstaddr;
-		else
-			d = NULL;
-		if (act == 1) {
-			addr->s_addr = a->sin_addr.s_addr;
-			net->s_addr = n->sin_addr.s_addr;
-			if (dst) {
-				if (ifa->ifa_flags & IFF_POINTOPOINT)
-					dst->s_addr = d->sin_addr.s_addr;
-				else
-					dst->s_addr = INADDR_ANY;
-			}
-			retval = 1;
-			break;
-		}
-		if (addr->s_addr == a->sin_addr.s_addr &&
-		    (net == NULL || net->s_addr == n->sin_addr.s_addr))
-		{
-			retval = 1;
-			break;
-		}
-	}
-	freeifaddrs(ifaddrs);
-	return retval;
-}
-
 void
 ipv4_freeroutes(struct rt_head *rts)
 {
@@ -586,26 +559,49 @@ ipv4_buildroutes(void)
 }
 
 static int
-delete_address(struct interface *iface)
+delete_address1(struct interface *ifp,
+    const struct in_addr *addr, const struct in_addr *net)
 {
-	int retval;
+	int r;
+	struct ipv4_state *state;
+	struct ipv4_addr *ap;
+
+	syslog(LOG_DEBUG, "%s: deleting IP address %s/%d",
+	    ifp->name, inet_ntoa(*addr), inet_ntocidr(*net));
+	r = ipv4_deleteaddress(ifp, addr, net);
+	if (r == -1 && errno != EADDRNOTAVAIL && errno != ENXIO &&
+	    errno != ENODEV)
+		syslog(LOG_ERR, "%s: %s: %m", ifp->name, __func__);
+
+	state = IPV4_STATE(ifp);
+	TAILQ_FOREACH(ap, &state->addrs, next) {
+		if (ap->addr.s_addr == addr->s_addr &&
+		    ap->net.s_addr == net->s_addr)
+		{
+			TAILQ_REMOVE(&state->addrs, ap, next);
+			free(ap);
+			break;
+		}
+	}
+	return r;
+}
+    
+static int
+delete_address(struct interface *ifp)
+{
+	int r;
 	struct if_options *ifo;
 	struct dhcp_state *state;
 
-	state = D_STATE(iface);
-	ifo = iface->options;
+	state = D_STATE(ifp);
+	ifo = ifp->options;
 	if (ifo->options & DHCPCD_INFORM ||
 	    (ifo->options & DHCPCD_STATIC && ifo->req_addr.s_addr == 0))
 		return 0;
-	syslog(LOG_DEBUG, "%s: deleting IP address %s/%d",
-	    iface->name, inet_ntoa(state->addr), inet_ntocidr(state->net));
-	retval = ipv4_deleteaddress(iface, &state->addr, &state->net);
-	if (retval == -1 && errno != EADDRNOTAVAIL && errno != ENXIO &&
-	    errno != ENODEV)
-		syslog(LOG_ERR, "del_address: %m");
+	r = delete_address1(ifp, &state->addr, &state->net);
 	state->addr.s_addr = 0;
 	state->net.s_addr = 0;
-	return retval;
+	return r;
 }
 
 void
@@ -616,6 +612,7 @@ ipv4_applyaddr(void *arg)
 	struct dhcp_message *dhcp;
 	struct dhcp_lease *lease;
 	struct if_options *ifo = ifp->options;
+	struct ipv4_addr *ap;
 	struct rt *rt;
 	int r;
 
@@ -640,10 +637,16 @@ ipv4_applyaddr(void *arg)
 		return;
 	}
 
-	/* This also changes netmask */
-	if (!(ifo->options & DHCPCD_INFORM) ||
-	    !ipv4_hasaddress(ifp->name, &lease->addr, &lease->net))
-	{
+	/* If the netmask is different, delete the addresss */
+	ap = ipv4_findaddr(ifp, &lease->addr, NULL);
+	if (ap && ap->net.s_addr != lease->net.s_addr)
+		delete_address1(ifp, &ap->addr, &ap->net);
+
+	if (ipv4_findaddr(ifp, &lease->addr, &lease->net))
+		syslog(LOG_DEBUG, "%s: IP address %s/%d already exists",
+		    ifp->name, inet_ntoa(lease->addr),
+		    inet_ntocidr(lease->net));
+	else {
 		syslog(LOG_DEBUG, "%s: adding IP address %s/%d",
 		    ifp->name, inet_ntoa(lease->addr),
 		    inet_ntocidr(lease->net));
@@ -687,62 +690,74 @@ ipv4_applyaddr(void *arg)
 }
 
 void
-ipv4_handleifa(int type, const char *ifname,
-    struct in_addr *addr, struct in_addr *net, struct in_addr *dst)
+ipv4_handleifa(int type, struct if_head *ifs, const char *ifname,
+    const struct in_addr *addr, const struct in_addr *net,
+    const struct in_addr *dst)
 {
 	struct interface *ifp;
-	struct if_options *ifo;
-	struct dhcp_state *state;
-	int i;
+	struct ipv4_state *state;
+	struct ipv4_addr *ap;
 
+	if (ifs == NULL)
+		ifs = ifaces;
+	if (ifs == NULL)
+		return;
 	if (addr->s_addr == INADDR_ANY)
 		return;
-	TAILQ_FOREACH(ifp, ifaces, next) {
+
+	TAILQ_FOREACH(ifp, ifs, next) {
 		if (strcmp(ifp->name, ifname) == 0)
 			break;
 	}
 	if (ifp == NULL)
 		return;
 
-	state = D_STATE(ifp);
-	if (state == NULL)
-		return;
-
-	if (type == RTM_DELADDR) {
-		if (state->new &&
-		    state->new->yiaddr == addr->s_addr)
-			syslog(LOG_INFO, "%s: removing IP address %s/%d",
-			    ifp->name, inet_ntoa(state->lease.addr),
-			    inet_ntocidr(state->lease.net));
-		return;
+	state = IPV4_STATE(ifp);
+	if (state == NULL) {
+	        ifp->if_data[IF_DATA_IPV4] = malloc(sizeof(*state));
+		state = IPV4_STATE(ifp);
+		if (state == NULL) {
+			syslog(LOG_ERR, "%s: %m", __func__);
+			return;
+		}
+		TAILQ_INIT(&state->addrs);
+		ap = NULL;
+	} else
+		ap = ipv4_findaddr(ifp, addr, net);
+	if (type == RTM_NEWADDR && ap == NULL) {
+		ap = malloc(sizeof(*ap));
+		if (ap == NULL) {
+			syslog(LOG_ERR, "%s: %m", __func__);
+			return;
+		}
+		ap->addr.s_addr = addr->s_addr;
+		ap->net.s_addr = net->s_addr;
+		if (dst)
+			ap->dst.s_addr = dst->s_addr;
+		else
+			ap->dst.s_addr = INADDR_ANY;
+		TAILQ_INSERT_TAIL(&state->addrs, ap, next);
+	} else if (type == RTM_DELADDR) {
+		if (ap == NULL)
+			return;
+		TAILQ_REMOVE(&state->addrs, ap, next);
+		free(ap);
 	}
 
-	if (type != RTM_NEWADDR)
-		return;
-
-	ifo = ifp->options;
-	if ((ifo->options & (DHCPCD_INFORM | DHCPCD_STATIC)) == 0 ||
-	    ifo->req_addr.s_addr != INADDR_ANY)
-		return;
+	dhcp_handleifa(type, ifp, addr, net, dst);
+}
 
-	free(state->old);
-	state->old = state->new;
-	state->new = dhcp_message_new(addr, net);
-	state->dst.s_addr = dst ? dst->s_addr : INADDR_ANY;
-	if (dst) {
-		for (i = 1; i < 255; i++)
-			if (i != DHO_ROUTER && has_option_mask(ifo->dstmask,i))
-				dhcp_message_add_addr(state->new, i, *dst);
-	}
-	state->reason = "STATIC";
-	ipv4_buildroutes();
-	script_runreason(ifp, state->reason);
-	if (ifo->options & DHCPCD_INFORM) {
-		state->state = DHS_INFORM;
-		state->xid = dhcp_xid(ifp);
-		state->lease.server.s_addr = dst ? dst->s_addr : INADDR_ANY;
-		state->addr = *addr;
-		state->net = *net;
-		dhcp_inform(ifp);
+void
+ipv4_free(struct interface *ifp)
+{
+	struct ipv4_state *state;
+	struct ipv4_addr *addr;
+
+	state = IPV4_STATE(ifp);
+	if (state) {
+		while ((addr = TAILQ_FIRST(&state->addrs))) {
+			TAILQ_REMOVE(&state->addrs, addr, next);
+			free(addr);
+		}
 	}
 }
diff --git a/ipv4.h b/ipv4.h
index eec0000a..ebab2cd3 100644
--- a/ipv4.h
+++ b/ipv4.h
@@ -41,6 +41,23 @@ struct rt {
 };
 TAILQ_HEAD(rt_head, rt);
 
+struct ipv4_addr {
+	TAILQ_ENTRY(ipv4_addr) next;
+	struct in_addr addr;
+	struct in_addr net;
+	struct in_addr dst;
+};
+TAILQ_HEAD(ipv4_addrhead, ipv4_addr);
+
+struct ipv4_state {
+	struct ipv4_addrhead addrs;
+};
+
+#define IPV4_STATE(ifp)							       \
+	((struct ipv4_state *)(ifp)->if_data[IF_DATA_IPV4])
+#define IPV4_CSTATE(ifp)						       \
+	((const struct ipv4_state *)(ifp)->if_data[IF_DATA_IPV4])
+
 #ifdef INET
 int ipv4_init(void);
 int inet_ntocidr(struct in_addr);
@@ -52,11 +69,11 @@ void ipv4_buildroutes(void);
 void ipv4_applyaddr(void *);
 int ipv4_routedeleted(const struct rt *);
 
-void ipv4_handleifa(int, const char *,
-    struct in_addr *, struct in_addr *, struct in_addr *);
+struct ipv4_addr *ipv4_findaddr(struct interface *,
+    const struct in_addr *, const struct in_addr *);
+void ipv4_handleifa(int, struct if_head *, const char *,
+    const struct in_addr *, const struct in_addr *, const struct in_addr *);
 
-int ipv4_doaddress(const char *,
-    struct in_addr *, struct in_addr *, struct in_addr *, int);
 int if_address(const struct interface *,
     const struct in_addr *, const struct in_addr *,
     const struct in_addr *, int);
@@ -66,10 +83,6 @@ int if_address(const struct interface *,
 	if_address(iface, addr, net, brd, 2)
 #define ipv4_deleteaddress(iface, addr, net)				      \
 	if_address(iface, addr, net, NULL, -1)
-#define ipv4_hasaddress(iface, addr, net)				      \
-	ipv4_doaddress(iface, addr, net, NULL, 0)
-#define ipv4_getaddress(iface, addr, net, dst)				      \
-	ipv4_doaddress(iface, addr, net, dst, 1)
 
 int if_route(const struct rt *rt, int);
 #define ipv4_addroute(rt) if_route(rt, 1)
@@ -82,6 +95,7 @@ int ipv4_opensocket(struct interface *, int);
 ssize_t ipv4_sendrawpacket(const struct interface *,
     int, const void *, ssize_t);
 ssize_t ipv4_getrawpacket(struct interface *, int, void *, ssize_t, int *);
+void ipv4_free(struct interface *);
 #else
 #define ipv4_init() -1
 #define ipv4_applyaddr(a) {}
diff --git a/net.c b/net.c
index 898b2221..0720a0f4 100644
--- a/net.c
+++ b/net.c
@@ -70,6 +70,7 @@
 #include "dhcp.h"
 #include "dhcp6.h"
 #include "if-options.h"
+#include "ipv4.h"
 #include "ipv6nd.h"
 #include "net.h"
 
@@ -138,6 +139,7 @@ free_interface(struct interface *ifp)
 
 	if (ifp == NULL)
 		return;
+	ipv4_free(ifp);
 	dhcp_free(ifp);
 	ipv6_free(ifp);
 	dhcp6_free(ifp);
@@ -223,6 +225,10 @@ discover_interfaces(int argc, char * const *argv)
 #ifdef __linux__
 	char ifn[IF_NAMESIZE];
 #endif
+#ifdef INET
+	const struct sockaddr_in *addr;
+	const struct sockaddr_in *net;
+	const struct sockaddr_in *dst;
 #ifdef INET6
 	const struct sockaddr_in6 *sin6;
 	int ifa_flags;
@@ -441,11 +447,29 @@ discover_interfaces(int argc, char * const *argv)
 		TAILQ_INSERT_TAIL(ifs, ifp, next);
 	}
 
-#ifdef INET6
 	for (ifa = ifaddrs; ifa; ifa = ifa->ifa_next) {
-		if (ifa->ifa_addr != NULL &&
-		    ifa->ifa_addr->sa_family == AF_INET6)
-		{
+		if (ifa->ifa_addr == NULL)
+			continue;
+		switch(ifa->ifa_addr->sa_family) {
+#ifdef INET
+		case AF_INET:
+			addr = (const struct sockaddr_in *)
+			    (void *)ifa->ifa_addr;
+			net = (const struct sockaddr_in *)
+			    (void *)ifa->ifa_netmask;
+			if (ifa->ifa_flags & IFF_POINTOPOINT)
+				dst = (const struct sockaddr_in *)
+				    (void *)ifa->ifa_dstaddr;
+			else
+				dst = NULL;
+			ipv4_handleifa(RTM_NEWADDR, ifs, ifa->ifa_name,
+				&addr->sin_addr,
+				&net->sin_addr,
+				dst ? &dst->sin_addr : NULL);
+			break;
+#endif
+#ifdef INET6
+		case AF_INET6:
 			sin6 = (const struct sockaddr_in6 *)
 			    (void *)ifa->ifa_addr;
 			ifa_flags = in6_addr_flags(ifa->ifa_name,
@@ -454,6 +478,8 @@ discover_interfaces(int argc, char * const *argv)
 				ipv6_handleifa(RTM_NEWADDR, ifs,
 				    ifa->ifa_name,
 				    &sin6->sin6_addr, ifa_flags);
+			break;
+#endif
 		}
 	}
 #endif