3 files changed, 107 insertions, 0 deletions

diff --git a/usr.sbin/dhcp/common/dispatch.c b/usr.sbin/dhcp/common/dispatch.c
index c830a5d6f34..d978223bc1b 100644
--- a/usr.sbin/dhcp/common/dispatch.c
+++ b/usr.sbin/dhcp/common/dispatch.c
@@ -139,6 +139,7 @@ void discover_interfaces (state)
 		if (ifa -> ifa_addr->sa_family == AF_LINK) {
 			struct sockaddr_dl *foo = ((struct sockaddr_dl *)
 						   (ifa -> ifa_addr));
+			tmp -> index = foo->sdl_index;
 			tmp -> hw_address.hlen = foo -> sdl_alen;
 			tmp -> hw_address.htype = HTYPE_ETHER; /* XXX */
 			memcpy (tmp -> hw_address.haddr,
diff --git a/usr.sbin/dhcp/dhclient/dhclient.c b/usr.sbin/dhcp/dhclient/dhclient.c
index d5dd7f08d31..959bd444e00 100644
--- a/usr.sbin/dhcp/dhclient/dhclient.c
+++ b/usr.sbin/dhcp/dhclient/dhclient.c
@@ -117,6 +117,107 @@ static int res_hnok(const char *dn);
 
 char *option_as_string (unsigned int code, unsigned char *data, int len);
 
+int  routefd;
+
+struct interface_info *
+isours(u_int16_t index)
+{
+	struct interface_info *ip;
+
+	for(ip = interfaces; ip; ip = ip->next) {
+		if (index == ip->index)
+			return (ip);
+	}
+	return (NULL);
+}
+
+#define ROUNDUP(a) \
+        ((a) > 0 ? (1 + (((a) - 1) | (sizeof(long) - 1))) : sizeof(long))
+#define ADVANCE(x, n) (x += ROUNDUP((n)->sa_len))
+
+int
+findproto(char *cp, int n)
+{
+	struct sockaddr *sa;
+	int i;
+
+	if (n == 0)
+		return -1;
+	for (i = 1; i; i <<= 1) {
+		if (i & n) {
+			sa = (struct sockaddr *)cp;
+			switch (i) {
+			case RTA_IFA:
+			case RTA_DST:
+			case RTA_GATEWAY:
+			case RTA_NETMASK:
+				if (sa->sa_family == AF_INET)
+					return AF_INET;
+				if (sa->sa_family == AF_INET6)
+					return AF_INET6;
+				break;
+			case RTA_IFP:
+				break;
+			}
+			ADVANCE(cp, sa);
+		}
+	}
+	return (-1);
+}
+
+void
+routehandler(struct protocol *p)
+{
+	char msg[2048];
+	struct rt_msghdr *rtm;
+	struct if_msghdr *ifm;
+	struct ifa_msghdr *ifam;
+	struct interface_info *ip;
+	ssize_t n;
+
+	n = read(routefd, &msg, sizeof msg);
+	rtm = (struct rt_msghdr *)msg;
+	if (n < sizeof(rtm->rtm_msglen) || n < rtm->rtm_msglen ||
+	    rtm->rtm_version != RTM_VERSION)
+		return;
+
+	switch (rtm->rtm_type) {
+	case RTM_NEWADDR:
+		ifam = (struct ifa_msghdr *)rtm;
+		if ((ip = isours(ifam->ifam_index)) == NULL)
+			break;
+		if (findproto((char *)(ifam + 1), ifam->ifam_addrs) != AF_INET)
+			break;
+		/* goto die; */
+		break;
+	case RTM_DELADDR:
+		ifam = (struct ifa_msghdr *)rtm;
+		if ((ip = isours(ifam->ifam_index)) == 0)
+			break;
+		if (findproto((char *)(ifam + 1), ifam->ifam_addrs) != AF_INET)
+			break;
+		goto die;
+		break;
+	case RTM_IFINFO:
+		ifm = (struct if_msghdr *)rtm;
+		if ((ip = isours(ifm->ifm_index)) == 0)
+			break;
+		if ((rtm->rtm_flags & RTF_UP) == 0)
+			goto die;
+		break;
+	default:
+		break;
+	}
+	return;
+
+die:
+	script_init(ip, "FAIL", (struct string_list *)0);
+	if (ip->client->alias)
+		script_write_params(ip, "alias_", ip->client->alias);
+	script_go(ip);
+	exit(1);
+}
+
 int main (argc, argv)
 	int argc;
 	char **argv;
@@ -262,6 +363,10 @@ int main (argc, argv)
 		}
 	}
 
+	routefd = socket(PF_ROUTE, SOCK_RAW, 0);
+	if (routefd != -1)
+		add_protocol("AF_ROUTE", routefd, routehandler, interfaces);
+
 	/* At this point, all the interfaces that the script thinks
 	   are relevant should be running, so now we once again call
 	   discover_interfaces(), and this time ask it to actually set
diff --git a/usr.sbin/dhcp/includes/dhcpd.h b/usr.sbin/dhcp/includes/dhcpd.h
index 16c1ec7382f..9936965615b 100644
--- a/usr.sbin/dhcp/includes/dhcpd.h
+++ b/usr.sbin/dhcp/includes/dhcpd.h
@@ -392,6 +392,7 @@ struct interface_info {
 	int noifmedia;
 	int errors;
 	int dead;
+	u_int16_t	index;
 };
 
 struct hardware_link {