X-Git-Url: https://git.librecmc.org/?p=oweals%2Fodhcpd.git;a=blobdiff_plain;f=src%2Fdhcpv6-ia.c;h=7c3ccad5b0d219ab8e95349481251ac4901c6c38;hp=abcbe8904b83a2691cee929c485df650b24e3f98;hb=36833ea26684b70b0d6093ecec648fe192a582ec;hpb=11ce6b5f0eaa9eac8cfcb77a89829275ebf04f96

diff --git a/src/dhcpv6-ia.c b/src/dhcpv6-ia.c
index abcbe89..7c3ccad 100644
--- a/src/dhcpv6-ia.c
+++ b/src/dhcpv6-ia.c
@@ -16,8 +16,6 @@
 #include "odhcpd.h"
 #include "dhcpv6.h"
 #include "dhcpv4.h"
-#include "libubox/md5.h"
-#include "libubox/usock.h"
 
 #include <time.h>
 #include <errno.h>
@@ -34,58 +32,80 @@
 #include <arpa/inet.h>
 #include <sys/timerfd.h>
 
-static void free_dhcpv6_assignment(struct dhcpv6_assignment *c);
-static void reconf_timer(struct uloop_timeout *event);
-static struct uloop_timeout reconf_event = {.cb = reconf_timer};
+#include <libubox/md5.h>
+#include <libubox/usock.h>
+
+#define ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) \
+    ((iface)->dhcpv6_assignall || (i) == (m) || \
+     (addrs)[(i)].prefix > 64)
+
+static void dhcpv6_netevent_cb(unsigned long event, struct netevent_handler_info *info);
+static void free_dhcpv6_assignment(struct dhcp_assignment *c);
+static void set_border_assignment_size(struct interface *iface, struct dhcp_assignment *b);
+static void handle_addrlist_change(struct netevent_handler_info *info);
+static void start_reconf(struct dhcp_assignment *a);
+static void stop_reconf(struct dhcp_assignment *a);
+static void valid_until_cb(struct uloop_timeout *event);
+
+static struct netevent_handler dhcpv6_netevent_handler = { .cb = dhcpv6_netevent_cb, };
+static struct uloop_timeout valid_until_timeout = {.cb = valid_until_cb};
 static uint32_t serial = 0;
 static uint8_t statemd5[16];
 
 int dhcpv6_ia_init(void)
 {
-	uloop_timeout_set(&reconf_event, 2000);
+	uloop_timeout_set(&valid_until_timeout, 1000);
+
+	netlink_add_netevent_handler(&dhcpv6_netevent_handler);
+
 	return 0;
 }
 
-int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
+int dhcpv6_ia_setup_interface(struct interface *iface, bool enable)
 {
 	if (!enable && iface->ia_assignments.next) {
-		struct dhcpv6_assignment *c;
+		struct dhcp_assignment *c;
 
 		while (!list_empty(&iface->ia_assignments)) {
-			c = list_first_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
+			c = list_first_entry(&iface->ia_assignments, struct dhcp_assignment, head);
 			free_dhcpv6_assignment(c);
 		}
 	}
 
-	if (enable && iface->dhcpv6 == RELAYD_SERVER) {
+	if (enable && iface->dhcpv6 == MODE_SERVER) {
+		struct dhcp_assignment *border;
+		struct lease *lease;
+
 		if (!iface->ia_assignments.next)
 			INIT_LIST_HEAD(&iface->ia_assignments);
 
 		if (list_empty(&iface->ia_assignments)) {
-			struct dhcpv6_assignment *border = calloc(1, sizeof(*border));
+			border = calloc(1, sizeof(*border));
+
 			if (!border) {
-				syslog(LOG_ERR, "Calloc failed for border on interface %s", iface->ifname);
+				syslog(LOG_ERR, "Calloc failed for border on %s", iface->name);
 				return -1;
 			}
 
 			border->length = 64;
 			list_add(&border->head, &iface->ia_assignments);
-		}
+		} else
+			border = list_last_entry(&iface->ia_assignments, struct dhcp_assignment, head);
+
+		set_border_assignment_size(iface, border);
 
 		/* Parse static entries */
-		struct lease *lease;
 		list_for_each_entry(lease, &leases, head) {
 			/* Construct entry */
 			size_t duid_len = lease->duid_len ? lease->duid_len : 14;
-			struct dhcpv6_assignment *a = calloc(1, sizeof(*a) + duid_len);
+			struct dhcp_assignment *a = calloc(1, sizeof(*a) + duid_len);
 			if (!a) {
-				syslog(LOG_ERR, "Calloc failed for static lease assignment on interface %s",
-					iface->ifname);
+				syslog(LOG_ERR, "Calloc failed for static lease assignment on %s",
+					iface->name);
 				return -1;
 			}
 
-			if (lease->dhcpv4_leasetime > 0)
-				a->leasetime = lease->dhcpv4_leasetime;
+			a->leasetime = lease->dhcpv4_leasetime;
 
 			a->clid_len = duid_len;
 			a->length = 128;
@@ -105,7 +125,7 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
 			a->valid_until = 0;
 
 			/* Assign to all interfaces */
-			struct dhcpv6_assignment *c;
+			struct dhcp_assignment *c;
 			list_for_each_entry(c, &iface->ia_assignments, head) {
 				if (c->length != 128 || c->assigned > a->assigned) {
 					list_add_tail(&a->head, &c->head);
@@ -116,6 +136,7 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
 			}
 
 			if (a->head.next) {
+				a->iface = iface;
 				if (lease->hostname[0]) {
 					free(a->hostname);
 					a->hostname = strdup(lease->hostname);
@@ -127,7 +148,25 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
 	return 0;
 }
 
-static void free_dhcpv6_assignment(struct dhcpv6_assignment *c)
+
+static void dhcpv6_netevent_cb(unsigned long event, struct netevent_handler_info *info)
+{
+	struct interface *iface = info->iface;
+
+	if (!iface || iface->dhcpv6 != MODE_SERVER)
+		return;
+
+	switch (event) {
+	case NETEV_ADDR6LIST_CHANGE:
+		handle_addrlist_change(info);
+		break;
+	default:
+		break;
+	}
+}
+
+
+static void free_dhcpv6_assignment(struct dhcp_assignment *c)
 {
 	if (c->managed_sock.fd.registered) {
 		ustream_free(&c->managed_sock.stream);
@@ -137,31 +176,39 @@ static void free_dhcpv6_assignment(struct dhcpv6_assignment *c)
 	if (c->head.next)
 		list_del(&c->head);
 
+	if (c->reconf_cnt)
+		stop_reconf(c);
+
 	free(c->managed);
 	free(c->hostname);
 	free(c);
 }
 
+static inline bool valid_prefix_length(const struct dhcp_assignment *a, const uint8_t prefix_length)
+{
+	return (a->managed_size || a->length > prefix_length);
+}
+
 static inline bool valid_addr(const struct odhcpd_ipaddr *addr, time_t now)
 {
 	return (addr->prefix <= 96 && addr->preferred > (uint32_t)now);
 }
 
-static size_t elect_addr(const struct odhcpd_ipaddr *addrs, const size_t addrlen)
+static size_t get_preferred_addr(const struct odhcpd_ipaddr *addrs, const size_t addrlen)
 {
 	size_t i, m;
 
 	for (i = 0, m = 0; i < addrlen; ++i) {
 		if (addrs[i].preferred > addrs[m].preferred ||
-			(addrs[i].preferred == addrs[m].preferred &&
-			 memcmp(&addrs[i].addr, &addrs[m].addr, 16) > 0))
+				(addrs[i].preferred == addrs[m].preferred &&
+				memcmp(&addrs[i].addr, &addrs[m].addr, 16) > 0))
 			m = i;
 	}
 
 	return m;
 }
 
-static int send_reconf(struct interface *iface, struct dhcpv6_assignment *assign)
+static int send_reconf(struct dhcp_assignment *assign)
 {
 	struct {
 		struct dhcpv6_client_header hdr;
@@ -193,6 +240,7 @@ static int send_reconf(struct interface *iface, struct dhcpv6_assignment *assign
 		.clid_len = htons(assign->clid_len),
 		.clid_data = {0},
 	};
+	struct interface *iface = assign->iface;
 
 	odhcpd_get_mac(iface, reconf_msg.mac);
 	memcpy(reconf_msg.clid_data, assign->clid_data, assign->clid_len);
@@ -224,139 +272,199 @@ static int send_reconf(struct interface *iface, struct dhcpv6_assignment *assign
 	return odhcpd_send(iface->dhcpv6_event.uloop.fd, &assign->peer, &iov, 1, iface);
 }
 
-void dhcpv6_write_statefile(void)
+void dhcpv6_ia_enum_addrs(struct interface *iface, struct dhcp_assignment *c,
+				time_t now, dhcpv6_binding_cb_handler_t func, void *arg)
 {
+	struct odhcpd_ipaddr *addrs = (c->managed) ? c->managed : iface->addr6;
+	size_t addrlen = (c->managed) ? (size_t)c->managed_size : iface->addr6_len;
+	size_t m = get_preferred_addr(addrs, addrlen);
+
+	for (size_t i = 0; i < addrlen; ++i) {
+		struct in6_addr addr;
+		uint32_t pref, valid;
+		int prefix = c->managed ? addrs[i].prefix : c->length;
+
+		if (!valid_addr(&addrs[i], now))
+			continue;
+
+		addr = addrs[i].addr.in6;
+		pref = addrs[i].preferred;
+		valid = addrs[i].valid;
+		if (prefix == 128) {
+			if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs))
+				continue;
+
+			addr.s6_addr32[3] = htonl(c->assigned);
+		} else {
+			if (!valid_prefix_length(c, addrs[i].prefix))
+				continue;
+
+			addr.s6_addr32[1] |= htonl(c->assigned);
+			addr.s6_addr32[2] = addr.s6_addr32[3] = 0;
+		}
+
+		if (pref != UINT32_MAX)
+			pref -= now;
+
+		if (valid != UINT32_MAX)
+			valid -= now;
+
+		func(&addr, prefix, pref, valid, arg);
+	}
+}
+
+struct write_ctxt {
+	FILE *fp;
 	md5_ctx_t md5;
-	md5_begin(&md5);
+	struct dhcp_assignment *c;
+	struct interface *iface;
+	char *buf;
+	int buf_len;
+	int buf_idx;
+};
+
+void dhcpv6_write_ia_addr(struct in6_addr *addr, int prefix, _unused uint32_t pref,
+				_unused uint32_t valid, void *arg)
+{
+	struct write_ctxt *ctxt = (struct write_ctxt *)arg;
+	char ipbuf[INET6_ADDRSTRLEN];
+
+	inet_ntop(AF_INET6, addr, ipbuf, sizeof(ipbuf) - 1);
+
+	if (ctxt->c->length == 128 && ctxt->c->hostname &&
+	    !(ctxt->c->flags & OAF_BROKEN_HOSTNAME)) {
+		fputs(ipbuf, ctxt->fp);
+
+		char b[256];
+		if (dn_expand(ctxt->iface->search, ctxt->iface->search + ctxt->iface->search_len,
+				ctxt->iface->search, b, sizeof(b)) > 0)
+			fprintf(ctxt->fp, "\t%s.%s", ctxt->c->hostname, b);
+
+		fprintf(ctxt->fp, "\t%s\n", ctxt->c->hostname);
+		md5_hash(ipbuf, strlen(ipbuf), &ctxt->md5);
+		md5_hash(ctxt->c->hostname, strlen(ctxt->c->hostname), &ctxt->md5);
+	}
+
+	ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx,ctxt->buf_len - ctxt->buf_idx,
+					"%s/%d ", ipbuf, prefix);
+}
+
+void dhcpv6_ia_write_statefile(void)
+{
+	struct write_ctxt ctxt;
+
+	md5_begin(&ctxt.md5);
 
 	if (config.dhcp_statefile) {
 		time_t now = odhcpd_time(), wall_time = time(NULL);
 		int fd = open(config.dhcp_statefile, O_CREAT | O_WRONLY | O_CLOEXEC, 0644);
+		char leasebuf[512];
+
 		if (fd < 0)
 			return;
-
-		lockf(fd, F_LOCK, 0);
+		int ret;
+		ret = lockf(fd, F_LOCK, 0);
+		if (ret < 0) {
+			close(fd);
+			return;
+		}
 		if (ftruncate(fd, 0) < 0) {}
 
-		FILE *fp = fdopen(fd, "w");
-		if (!fp) {
+		ctxt.fp = fdopen(fd, "w");
+		if (!ctxt.fp) {
 			close(fd);
 			return;
 		}
 
-		struct interface *iface;
-		list_for_each_entry(iface, &interfaces, head) {
-			if (iface->dhcpv6 != RELAYD_SERVER && iface->dhcpv4 != RELAYD_SERVER)
+		ctxt.buf = leasebuf;
+		ctxt.buf_len = sizeof(leasebuf);
+
+		avl_for_each_element(&interfaces, ctxt.iface, avl) {
+			if (ctxt.iface->dhcpv6 != MODE_SERVER &&
+					ctxt.iface->dhcpv4 != MODE_SERVER)
 				continue;
 
-			if (iface->dhcpv6 == RELAYD_SERVER && iface->ia_assignments.next) {
-				struct dhcpv6_assignment *c;
-				list_for_each_entry(c, &iface->ia_assignments, head) {
-					if (!(c->flags & OAF_BOUND) || c->managed_size < 0)
+			if (ctxt.iface->dhcpv6 == MODE_SERVER &&
+					ctxt.iface->ia_assignments.next) {
+				list_for_each_entry(ctxt.c, &ctxt.iface->ia_assignments, head) {
+					if (!(ctxt.c->flags & OAF_BOUND) || ctxt.c->managed_size < 0)
 						continue;
 
-					char ipbuf[INET6_ADDRSTRLEN];
-					char leasebuf[512];
 					char duidbuf[264];
-					odhcpd_hexlify(duidbuf, c->clid_data, c->clid_len);
-
-					/* iface DUID iaid hostname lifetime assigned length [addrs...] */
-					int l = snprintf(leasebuf, sizeof(leasebuf), "# %s %s %x %s %ld %x %u ",
-							iface->ifname, duidbuf, ntohl(c->iaid),
-							(c->hostname ? c->hostname : "-"),
-							(c->valid_until > now ?
-								(c->valid_until - now + wall_time) :
-								(INFINITE_VALID(c->valid_until) ? -1 : 0)),
-							c->assigned, (unsigned)c->length);
-
-					struct in6_addr addr;
-					struct odhcpd_ipaddr *addrs = (c->managed) ? c->managed : iface->ia_addr;
-					size_t addrlen = (c->managed) ? (size_t)c->managed_size : iface->ia_addr_len;
-					size_t m = elect_addr(addrs, addrlen);
-
-					for (size_t i = 0; i < addrlen; ++i) {
-						if (!valid_addr(&addrs[i], now) || (!INFINITE_VALID(c->valid_until) && c->valid_until <= now) ||
-								(iface->managed < RELAYD_MANAGED_NO_AFLAG && i != m &&
-										addrs[i].prefix <= 64))
-							continue;
-
-						addr = addrs[i].addr;
-						if (c->length == 128)
-							addr.s6_addr32[3] = htonl(c->assigned);
-						else
-							addr.s6_addr32[1] |= htonl(c->assigned);
-
-						inet_ntop(AF_INET6, &addr, ipbuf, sizeof(ipbuf) - 1);
 
-						if (c->length == 128 && c->hostname) {
-							fputs(ipbuf, fp);
+					odhcpd_hexlify(duidbuf, ctxt.c->clid_data, ctxt.c->clid_len);
 
-							char b[256];
-							if (dn_expand(iface->search, iface->search + iface->search_len,
-									iface->search, b, sizeof(b)) > 0)
-								fprintf(fp, "\t%s.%s", c->hostname, b);
-
-							fprintf(fp, "\t%s\n", c->hostname);
-							md5_hash(ipbuf, strlen(ipbuf), &md5);
-							md5_hash(c->hostname, strlen(c->hostname), &md5);
-						}
-
-						l += snprintf(leasebuf + l, sizeof(leasebuf) - l, "%s/%d ", ipbuf,
-								(c->managed_size) ? addrs[i].prefix : c->length);
-					}
-					leasebuf[l - 1] = '\n';
-					fwrite(leasebuf, 1, l, fp);
+					/* iface DUID iaid hostname lifetime assigned length [addrs...] */
+					ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s %x %s%s %ld %x %u ",
+								ctxt.iface->ifname, duidbuf, ntohl(ctxt.c->iaid),
+								(ctxt.c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
+								(ctxt.c->hostname ? ctxt.c->hostname : "-"),
+								(ctxt.c->valid_until > now ?
+									(ctxt.c->valid_until - now + wall_time) :
+									(INFINITE_VALID(ctxt.c->valid_until) ? -1 : 0)),
+								ctxt.c->assigned, (unsigned)ctxt.c->length);
+
+					if (INFINITE_VALID(ctxt.c->valid_until) || ctxt.c->valid_until > now)
+						dhcpv6_ia_enum_addrs(ctxt.iface, ctxt.c, now,
+									dhcpv6_write_ia_addr, &ctxt);
+
+					ctxt.buf[ctxt.buf_idx - 1] = '\n';
+					fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
 				}
 			}
 
-			if (iface->dhcpv4 == RELAYD_SERVER && iface->dhcpv4_assignments.next) {
-				struct dhcpv4_assignment *c;
-				list_for_each_entry(c, &iface->dhcpv4_assignments, head) {
+			if (ctxt.iface->dhcpv4 == MODE_SERVER &&
+					ctxt.iface->dhcpv4_assignments.next) {
+				struct dhcp_assignment *c;
+				list_for_each_entry(c, &ctxt.iface->dhcpv4_assignments, head) {
 					if (!(c->flags & OAF_BOUND))
 						continue;
 
 					char ipbuf[INET6_ADDRSTRLEN];
-					char leasebuf[512];
 					char duidbuf[16];
 					odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
 
 					/* iface DUID iaid hostname lifetime assigned length [addrs...] */
-					int l = snprintf(leasebuf, sizeof(leasebuf), "# %s %s ipv4 %s %ld %x 32 ",
-							iface->ifname, duidbuf,
-							(c->hostname ? c->hostname : "-"),
-							(c->valid_until > now ?
-								(c->valid_until - now + wall_time) :
-								(INFINITE_VALID(c->valid_until) ? -1 : 0)),
-							c->addr);
-
-					struct in_addr addr = {htonl(c->addr)};
+					ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s ipv4 %s%s %ld %x 32 ",
+								ctxt.iface->ifname, duidbuf,
+								(c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
+								(c->hostname ? c->hostname : "-"),
+								(c->valid_until > now ?
+									(c->valid_until - now + wall_time) :
+									(INFINITE_VALID(c->valid_until) ? -1 : 0)),
+								ntohl(c->addr));
+
+					struct in_addr addr = {.s_addr = c->addr};
 					inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
 
-					if (c->hostname) {
-						fputs(ipbuf, fp);
+					if (c->hostname && !(c->flags & OAF_BROKEN_HOSTNAME)) {
+						fputs(ipbuf, ctxt.fp);
 
 						char b[256];
-						if (dn_expand(iface->search, iface->search + iface->search_len,
-								iface->search, b, sizeof(b)) > 0)
-							fprintf(fp, "\t%s.%s", c->hostname, b);
-
-						fprintf(fp, "\t%s\n", c->hostname);
-						md5_hash(ipbuf, strlen(ipbuf), &md5);
-						md5_hash(c->hostname, strlen(c->hostname), &md5);
+						if (dn_expand(ctxt.iface->search,
+								ctxt.iface->search + ctxt.iface->search_len,
+								ctxt.iface->search, b, sizeof(b)) > 0)
+							fprintf(ctxt.fp, "\t%s.%s", c->hostname, b);
+
+						fprintf(ctxt.fp, "\t%s\n", c->hostname);
+						md5_hash(ipbuf, strlen(ipbuf), &ctxt.md5);
+						md5_hash(c->hostname, strlen(c->hostname), &ctxt.md5);
 					}
 
-					l += snprintf(leasebuf + l, sizeof(leasebuf) - l, "%s/32 ", ipbuf);
-					leasebuf[l - 1] = '\n';
-					fwrite(leasebuf, 1, l, fp);
+					ctxt.buf_idx += snprintf(ctxt.buf + ctxt.buf_idx,
+									ctxt.buf_len - ctxt.buf_idx,
+									"%s/32 ", ipbuf);
+					ctxt.buf[ctxt.buf_idx - 1] = '\n';
+					fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
 				}
 			}
 		}
 
-		fclose(fp);
+		fclose(ctxt.fp);
 	}
 
 	uint8_t newmd5[16];
-	md5_end(newmd5, &md5);
+	md5_end(newmd5, &ctxt.md5);
 
 	if (config.dhcp_cb && memcmp(newmd5, statemd5, sizeof(newmd5))) {
 		memcpy(statemd5, newmd5, sizeof(statemd5));
@@ -368,27 +476,53 @@ void dhcpv6_write_statefile(void)
 	}
 }
 
-
-static void apply_lease(struct interface *iface, struct dhcpv6_assignment *a, bool add)
+static void __apply_lease(struct interface *iface, struct dhcp_assignment *a,
+		struct odhcpd_ipaddr *addrs, ssize_t addr_len, bool add)
 {
-	if (a->length > 64 || a->managed_size < 0)
+	if (a->length > 64)
 		return;
 
-	struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
-	size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
-
-	for (size_t i = 0; i < addrlen; ++i) {
-		struct in6_addr prefix = addrs[i].addr;
+	for (ssize_t i = 0; i < addr_len; ++i) {
+		struct in6_addr prefix = addrs[i].addr.in6;
 		prefix.s6_addr32[1] |= htonl(a->assigned);
-		odhcpd_setup_route(&prefix, (a->managed_size) ? addrs[i].prefix : a->length,
-				iface, &a->peer.sin6_addr, 1024, add);
+		prefix.s6_addr32[2] = prefix.s6_addr32[3] = 0;
+		netlink_setup_route(&prefix, (a->managed_size) ? addrs[i].prefix : a->length,
+				iface->ifindex, &a->peer.sin6_addr, 1024, add);
 	}
 }
 
+static void apply_lease(struct interface *iface, struct dhcp_assignment *a, bool add)
+{
+	struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
+	ssize_t addrlen = (a->managed) ? a->managed_size : (ssize_t)iface->addr6_len;
+
+	__apply_lease(iface, a, addrs, addrlen, add);
+}
+
+/* Set border assignment size based on the IPv6 address prefixes */
+static void set_border_assignment_size(struct interface *iface, struct dhcp_assignment *b)
+{
+	time_t now = odhcpd_time();
+	int minprefix = -1;
+
+	for (size_t i = 0; i < iface->addr6_len; ++i) {
+		if (iface->addr6[i].preferred > (uint32_t)now &&
+				iface->addr6[i].prefix < 64 &&
+				iface->addr6[i].prefix > minprefix)
+			minprefix = iface->addr6[i].prefix;
+	}
+
+	if (minprefix > 32 && minprefix <= 64)
+		b->assigned = 1U << (64 - minprefix);
+	else
+		b->assigned = 0;
+}
+
 /* More data was received from TCP connection */
 static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
 {
-	struct dhcpv6_assignment *c = container_of(s, struct dhcpv6_assignment, managed_sock);
+	struct ustream_fd *fd = container_of(s, struct ustream_fd, stream);
+	struct dhcp_assignment *c = container_of(fd, struct dhcp_assignment, managed_sock);
 	time_t now = odhcpd_time();
 	bool first = c->managed_size < 0;
 
@@ -451,7 +585,7 @@ static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
 
 	if (first && c->managed_size == 0)
 		free_dhcpv6_assignment(c);
-	else if (first & !(c->flags & OAF_STATIC))
+	else if (first && !(c->flags & OAF_STATIC))
 		c->valid_until = now + 150;
 }
 
@@ -459,7 +593,8 @@ static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
 /* TCP transmission has ended, either because of success or timeout or other error */
 static void managed_handle_pd_done(struct ustream *s)
 {
-	struct dhcpv6_assignment *c = container_of(s, struct dhcpv6_assignment, managed_sock);
+	struct ustream_fd *fd = container_of(s, struct ustream_fd, stream);
+	struct dhcp_assignment *c = container_of(fd, struct dhcp_assignment, managed_sock);
 
 	if (!(c->flags & OAF_STATIC))
 		c->valid_until = odhcpd_time() + 15;
@@ -470,14 +605,16 @@ static void managed_handle_pd_done(struct ustream *s)
 		c->reconf_cnt = 1;
 }
 
-static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
+static bool assign_pd(struct interface *iface, struct dhcp_assignment *assign)
 {
-	struct dhcpv6_assignment *c;
+	struct dhcp_assignment *c;
 
 	if (iface->dhcpv6_pd_manager[0]) {
 		int fd = usock(USOCK_UNIX | USOCK_TCP, iface->dhcpv6_pd_manager, NULL);
 		if (fd >= 0) {
+			struct pollfd pfd = { .fd = fd, .events = POLLIN };
 			char iaidbuf[298];
+
 			odhcpd_hexlify(iaidbuf, assign->clid_data, assign->clid_len);
 
 			assign->managed_sock.stream.notify_read = managed_handle_pd_data;
@@ -494,8 +631,11 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
 			list_add(&assign->head, &iface->ia_assignments);
 
 			/* Wait initial period of up to 250ms for immediate assignment */
-			struct pollfd pfd = { .fd = fd, .events = POLLIN };
-			poll(&pfd, 1, 250);
+			if (poll(&pfd, 1, 250) < 0) {
+				syslog(LOG_ERR, "poll(): %m");
+				return false;
+			}
+
 			managed_handle_pd_data(&assign->managed_sock.stream, 0);
 
 			if (fcntl(fd, F_GETFL) >= 0 && assign->managed_size > 0)
@@ -503,7 +643,7 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
 		}
 
 		return false;
-	} else if (iface->ia_addr_len < 1)
+	} else if (iface->addr6_len < 1)
 		return false;
 
 	/* Try honoring the hint first */
@@ -515,7 +655,10 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
 
 			if (assign->assigned >= current && assign->assigned + asize < c->assigned) {
 				list_add_tail(&assign->head, &c->head);
-				apply_lease(iface, assign, true);
+
+				if (assign->flags & OAF_BOUND)
+					apply_lease(iface, assign, true);
+
 				return true;
 			}
 
@@ -534,7 +677,10 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
 		if (current + asize < c->assigned) {
 			assign->assigned = current;
 			list_add_tail(&assign->head, &c->head);
-			apply_lease(iface, assign, true);
+
+			if (assign->flags & OAF_BOUND)
+				apply_lease(iface, assign, true);
+
 			return true;
 		}
 
@@ -545,7 +691,7 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
 	return false;
 }
 
-static bool assign_na(struct interface *iface, struct dhcpv6_assignment *assign)
+static bool assign_na(struct interface *iface, struct dhcp_assignment *assign)
 {
 	/* Seed RNG with checksum of DUID */
 	uint32_t seed = 0;
@@ -558,7 +704,7 @@ static bool assign_na(struct interface *iface, struct dhcpv6_assignment *assign)
 		uint32_t try;
 		do try = ((uint32_t)rand()) % 0x0fff; while (try < 0x100);
 
-		struct dhcpv6_assignment *c;
+		struct dhcp_assignment *c;
 		list_for_each_entry(c, &iface->ia_assignments, head) {
 			if (c->length == 0)
 				continue;
@@ -575,42 +721,23 @@ static bool assign_na(struct interface *iface, struct dhcpv6_assignment *assign)
 	return false;
 }
 
-void dhcpv6_ia_preupdate(struct interface *iface)
+static void handle_addrlist_change(struct netevent_handler_info *info)
 {
-	if (iface->dhcpv6 != RELAYD_SERVER)
-		return;
-
-	struct dhcpv6_assignment *c, *border = list_last_entry(
-			&iface->ia_assignments, struct dhcpv6_assignment, head);
-
-	list_for_each_entry(c, &iface->ia_assignments, head)
-		if (c != border && !iface->managed)
-			apply_lease(iface, c, false);
-}
-
-void dhcpv6_ia_postupdate(struct interface *iface, time_t now)
-{
-	if (iface->dhcpv6 != RELAYD_SERVER)
-		return;
+	struct interface *iface = info->iface;
+	struct dhcp_assignment *c, *d, *border = list_last_entry(
+			&iface->ia_assignments, struct dhcp_assignment, head);
+	struct list_head reassign = LIST_HEAD_INIT(reassign);
+	time_t now = odhcpd_time();
 
-	int minprefix = -1;
-	for (size_t i = 0; i < iface->ia_addr_len; ++i) {
-		if (iface->ia_addr[i].preferred > (uint32_t)now &&
-				iface->ia_addr[i].prefix < 64 &&
-				iface->ia_addr[i].prefix > minprefix)
-			minprefix = iface->ia_addr[i].prefix;
+	list_for_each_entry(c, &iface->ia_assignments, head) {
+		if (c != border && iface->ra_managed == RA_MANAGED_NO_MFLAG
+				&& (c->flags & OAF_BOUND))
+			__apply_lease(iface, c, info->addrs_old.addrs,
+					info->addrs_old.len, false);
 	}
 
-	struct dhcpv6_assignment *border = list_last_entry(
-			&iface->ia_assignments, struct dhcpv6_assignment, head);
+	set_border_assignment_size(iface, border);
 
-	if (minprefix > 32 && minprefix <= 64)
-		border->assigned = 1U << (64 - minprefix);
-	else
-		border->assigned = 0;
-
-	struct list_head reassign = LIST_HEAD_INIT(reassign);
-	struct dhcpv6_assignment *c, *d;
 	list_for_each_entry_safe(c, d, &iface->ia_assignments, head) {
 		if (c->clid_len == 0 || (!INFINITE_VALID(c->valid_until) && c->valid_until < now) ||
 				c->managed_size)
@@ -618,25 +745,24 @@ void dhcpv6_ia_postupdate(struct interface *iface, time_t now)
 
 		if (c->length < 128 && c->assigned >= border->assigned && c != border)
 			list_move(&c->head, &reassign);
-		else if (c != border)
+		else if (c != border && (c->flags & OAF_BOUND))
 			apply_lease(iface, c, true);
 
 		if (c->accept_reconf && c->reconf_cnt == 0) {
-			c->reconf_cnt = 1;
-			c->reconf_sent = now;
-			send_reconf(iface, c);
+			struct dhcp_assignment *a;
+
+			start_reconf(c);
 
 			/* Leave all other assignments of that client alone */
-			struct dhcpv6_assignment *a;
 			list_for_each_entry(a, &iface->ia_assignments, head)
 				if (a != c && a->clid_len == c->clid_len &&
 						!memcmp(a->clid_data, c->clid_data, a->clid_len))
-					c->reconf_cnt = INT_MAX;
+					a->reconf_cnt = INT_MAX;
 		}
 	}
 
 	while (!list_empty(&reassign)) {
-		c = list_first_entry(&reassign, struct dhcpv6_assignment, head);
+		c = list_first_entry(&reassign, struct dhcp_assignment, head);
 		list_del(&c->head);
 		if (!assign_pd(iface, c)) {
 			c->assigned = 0;
@@ -644,240 +770,296 @@ void dhcpv6_ia_postupdate(struct interface *iface, time_t now)
 		}
 	}
 
-	dhcpv6_write_statefile();
+	dhcpv6_ia_write_statefile();
 }
 
-static void reconf_timer(struct uloop_timeout *event)
+static void reconf_timeout_cb(struct uloop_timeout *event)
+{
+	struct dhcp_assignment *a = container_of(event, struct dhcp_assignment, reconf_timer);
+
+	if (a->reconf_cnt > 0 && a->reconf_cnt < DHCPV6_REC_MAX_RC) {
+		send_reconf(a);
+		uloop_timeout_set(&a->reconf_timer,
+					DHCPV6_REC_TIMEOUT << a->reconf_cnt);
+		a->reconf_cnt++;
+	} else
+		stop_reconf(a);
+}
+
+static void start_reconf(struct dhcp_assignment *a)
+{
+	uloop_timeout_set(&a->reconf_timer,
+				DHCPV6_REC_TIMEOUT << a->reconf_cnt);
+	a->reconf_timer.cb = reconf_timeout_cb;
+	a->reconf_cnt++;
+
+	send_reconf(a);
+}
+
+static void stop_reconf(struct dhcp_assignment *a)
+{
+	uloop_timeout_cancel(&a->reconf_timer);
+	a->reconf_cnt = 0;
+	a->reconf_timer.cb = NULL;
+}
+
+static void valid_until_cb(struct uloop_timeout *event)
 {
-	time_t now = odhcpd_time();
 	struct interface *iface;
-	list_for_each_entry(iface, &interfaces, head) {
-		if (iface->dhcpv6 != RELAYD_SERVER || iface->ia_assignments.next == NULL)
+	time_t now = odhcpd_time();
+
+	avl_for_each_element(&interfaces, iface, avl) {
+		struct dhcp_assignment *a, *n;
+
+		if (iface->dhcpv6 != MODE_SERVER || iface->ia_assignments.next == NULL)
 			continue;
 
-		struct dhcpv6_assignment *a, *n;
 		list_for_each_entry_safe(a, n, &iface->ia_assignments, head) {
 			if (!INFINITE_VALID(a->valid_until) && a->valid_until < now) {
 				if ((a->length < 128 && a->clid_len > 0) ||
 						(a->length == 128 && a->clid_len == 0))
 					free_dhcpv6_assignment(a);
 
-			} else if (a->reconf_cnt > 0 && a->reconf_cnt < 8 &&
-					now > a->reconf_sent + (1 << a->reconf_cnt)) {
-				++a->reconf_cnt;
-				a->reconf_sent = now;
-				send_reconf(iface, a);
 			}
 		}
 	}
-	uloop_timeout_set(event, 2000);
+	uloop_timeout_set(event, 1000);
 }
 
-static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
-		const struct dhcpv6_ia_hdr *ia, struct dhcpv6_assignment *a,
+static size_t build_ia(uint8_t *buf, size_t buflen, uint16_t status,
+		const struct dhcpv6_ia_hdr *ia, struct dhcp_assignment *a,
 		struct interface *iface, bool request)
 {
-	if (buflen < sizeof(*ia) + sizeof(struct dhcpv6_ia_prefix))
-		return 0;
-
-	struct dhcpv6_ia_hdr out = {ia->type, 0, ia->iaid, 0, 0};
-	size_t datalen = sizeof(out);
+	struct dhcpv6_ia_hdr o_ia = {
+		.type = ia->type,
+		.len = 0,
+		.iaid = ia->iaid,
+		.t1 = 0,
+		.t2 = 0,
+	};
+	size_t ia_len = sizeof(o_ia);
 	time_t now = odhcpd_time();
 
+	if (buflen < ia_len)
+		return 0;
+
 	if (status) {
 		struct __attribute__((packed)) {
 			uint16_t type;
 			uint16_t len;
-			uint16_t value;
-		} stat = {htons(DHCPV6_OPT_STATUS), htons(sizeof(stat) - 4),
-				htons(status)};
-
-		memcpy(buf + datalen, &stat, sizeof(stat));
-		datalen += sizeof(stat);
-	} else {
-		if (a) {
-			uint32_t leasetime;
-			if (a->leasetime > 0)
-				leasetime = a->leasetime;
-			else
-				leasetime = iface->dhcpv4_leasetime;
+			uint16_t val;
+		} o_status = {
+			.type = htons(DHCPV6_OPT_STATUS),
+			.len = htons(sizeof(o_status) - 4),
+			.val = htons(status),
+		};
 
-			if (leasetime == 0)
-				leasetime = 3600;
-			else if (leasetime < 60)
-				leasetime = 60;
+		memcpy(buf + ia_len, &o_status, sizeof(o_status));
+		ia_len += sizeof(o_status);
 
-			uint32_t pref = leasetime;
-			uint32_t valid = leasetime;
+		o_ia.len = htons(ia_len - 4);
+		memcpy(buf, &o_ia, sizeof(o_ia));
 
-			struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
-			size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
-			size_t m = elect_addr(addrs, addrlen);
+		return ia_len;
+	}
 
-			for (size_t i = 0; i < addrlen; ++i) {
-				uint32_t prefix_pref = addrs[i].preferred;
-				uint32_t prefix_valid = addrs[i].valid;
+	if (a) {
+		uint32_t leasetime;
 
-				if (!valid_addr(&addrs[i], now))
-					continue;
+		if (a->leasetime)
+			leasetime = a->leasetime;
+		else
+			leasetime = iface->dhcpv4_leasetime;
 
-				if (prefix_pref != UINT32_MAX)
-					prefix_pref -= now;
+		uint32_t pref = leasetime;
+		uint32_t valid = leasetime;
 
-				if (prefix_valid != UINT32_MAX)
-					prefix_valid -= now;
+		struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
+		size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->addr6_len;
+		size_t m = get_preferred_addr(addrs, addrlen);
 
-				if (a->length < 128) {
-					struct dhcpv6_ia_prefix p = {
-						.type = htons(DHCPV6_OPT_IA_PREFIX),
-						.len = htons(sizeof(p) - 4),
-						.preferred = htonl(prefix_pref),
-						.valid = htonl(prefix_valid),
-						.prefix = (a->managed_size) ? addrs[i].prefix : a->length,
-						.addr = addrs[i].addr
-					};
-					p.addr.s6_addr32[1] |= htonl(a->assigned);
+		for (size_t i = 0; i < addrlen; ++i) {
+			uint32_t prefix_pref = addrs[i].preferred;
+			uint32_t prefix_valid = addrs[i].valid;
 
-					size_t entrlen = sizeof(p) - 4;
+			if (!valid_addr(&addrs[i], now))
+				continue;
 
-					if (datalen + entrlen + 4 > buflen ||
-							(a->assigned == 0 && a->managed_size == 0) ||
-							(!a->managed_size && a->length <= addrs[i].prefix))
-						continue;
+			if (prefix_pref != UINT32_MAX)
+				prefix_pref -= now;
 
-					memcpy(buf + datalen, &p, sizeof(p));
-					datalen += entrlen + 4;
-				} else {
-					struct dhcpv6_ia_addr n = {
-						.type = htons(DHCPV6_OPT_IA_ADDR),
-						.len = htons(sizeof(n) - 4),
-						.addr = addrs[i].addr,
-						.preferred = htonl(prefix_pref),
-						.valid = htonl(prefix_valid)
-					};
-					n.addr.s6_addr32[3] = htonl(a->assigned);
-					size_t entrlen = sizeof(n) - 4;
+			if (prefix_valid != UINT32_MAX)
+				prefix_valid -= now;
 
-					if (iface->managed < RELAYD_MANAGED_NO_AFLAG && i != m &&
-							addrs[i].prefix <= 64)
-						continue;
+			if (a->length < 128) {
+				struct dhcpv6_ia_prefix o_ia_p = {
+					.type = htons(DHCPV6_OPT_IA_PREFIX),
+					.len = htons(sizeof(o_ia_p) - 4),
+					.preferred = htonl(prefix_pref),
+					.valid = htonl(prefix_valid),
+					.prefix = (a->managed_size) ? addrs[i].prefix : a->length,
+					.addr = addrs[i].addr.in6,
+				};
 
-					if (datalen + entrlen + 4 > buflen || a->assigned == 0)
-						continue;
+				o_ia_p.addr.s6_addr32[1] |= htonl(a->assigned);
+				o_ia_p.addr.s6_addr32[2] = o_ia_p.addr.s6_addr32[3] = 0;
 
-					memcpy(buf + datalen, &n, sizeof(n));
-					datalen += entrlen + 4;
-				}
+				if ((a->assigned == 0 && a->managed_size == 0) ||
+						!valid_prefix_length(a, addrs[i].prefix))
+					continue;
 
-				/* Calculate T1 / T2 based on non-deprecated addresses */
-				if (prefix_pref > 0) {
-					if (prefix_pref < pref)
-						pref = prefix_pref;
+				if (buflen < ia_len + sizeof(o_ia_p))
+					return 0;
 
-					if (prefix_valid < valid)
-						valid = prefix_valid;
-				}
-			}
+				memcpy(buf + ia_len, &o_ia_p, sizeof(o_ia_p));
+				ia_len += sizeof(o_ia_p);
+			} else {
+				struct dhcpv6_ia_addr o_ia_a = {
+					.type = htons(DHCPV6_OPT_IA_ADDR),
+					.len = htons(sizeof(o_ia_a) - 4),
+					.addr = addrs[i].addr.in6,
+					.preferred = htonl(prefix_pref),
+					.valid = htonl(prefix_valid)
+				};
+
+				o_ia_a.addr.s6_addr32[3] = htonl(a->assigned);
+
+				if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) ||
+						a->assigned == 0)
+					continue;
 
-			if (!INFINITE_VALID(a->valid_until))
-				/* UINT32_MAX is considered as infinite leasetime */
-				a->valid_until = (valid == UINT32_MAX) ? 0 : valid + now;
+				if (buflen < ia_len + sizeof(o_ia_a))
+					return 0;
 
-			out.t1 = htonl((pref == UINT32_MAX) ? pref : pref * 5 / 10);
-			out.t2 = htonl((pref == UINT32_MAX) ? pref : pref * 8 / 10);
+				memcpy(buf + ia_len, &o_ia_a, sizeof(o_ia_a));
+				ia_len += sizeof(o_ia_a);
+			}
 
-			if (!out.t1)
-				out.t1 = htonl(1);
+			/* Calculate T1 / T2 based on non-deprecated addresses */
+			if (prefix_pref > 0) {
+				if (prefix_pref < pref)
+					pref = prefix_pref;
 
-			if (!out.t2)
-				out.t2 = htonl(1);
+				if (prefix_valid < valid)
+					valid = prefix_valid;
+			}
 		}
 
-		if (!request) {
-			uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
-			uint16_t otype, olen;
-			dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
-				struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix*)&odata[-4];
-				struct dhcpv6_ia_addr *n = (struct dhcpv6_ia_addr*)&odata[-4];
-				if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*p) - 4) &&
-						(otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*n) - 4))
-					continue;
+		if (!INFINITE_VALID(a->valid_until))
+			/* UINT32_MAX is considered as infinite leasetime */
+			a->valid_until = (valid == UINT32_MAX) ? 0 : valid + now;
 
-				bool found = false;
-				if (a) {
-					struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
-					size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
-
-					for (size_t i = 0; i < addrlen; ++i) {
-						if (!valid_addr(&addrs[i], now))
-							continue;
-
-						struct in6_addr addr = addrs[i].addr;
-						if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
-							addr.s6_addr32[1] |= htonl(a->assigned);
-
-							if (!memcmp(&p->addr, &addr, sizeof(addr)) &&
-									p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
-								found = true;
-						} else {
-							addr.s6_addr32[3] = htonl(a->assigned);
-
-							if (!memcmp(&n->addr, &addr, sizeof(addr)))
-								found = true;
-						}
-					}
-				}
+		o_ia.t1 = htonl((pref == UINT32_MAX) ? pref : pref * 5 / 10);
+		o_ia.t2 = htonl((pref == UINT32_MAX) ? pref : pref * 8 / 10);
 
-				if (!found) {
-					if (otype == DHCPV6_OPT_IA_PREFIX) {
-						struct dhcpv6_ia_prefix inv = {
-							.type = htons(DHCPV6_OPT_IA_PREFIX),
-							.len = htons(sizeof(inv) - 4),
-							.preferred = 0,
-							.valid = 0,
-							.prefix = p->prefix,
-							.addr = p->addr
-						};
-
-						if (datalen + sizeof(inv) > buflen)
-							continue;
-
-						memcpy(buf + datalen, &inv, sizeof(inv));
-						datalen += sizeof(inv);
+		if (!o_ia.t1)
+			o_ia.t1 = htonl(1);
+
+		if (!o_ia.t2)
+			o_ia.t2 = htonl(1);
+	}
+
+	if (!request) {
+		uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
+		uint16_t otype, olen;
+
+		dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
+			struct dhcpv6_ia_prefix *ia_p = (struct dhcpv6_ia_prefix *)&odata[-4];
+			struct dhcpv6_ia_addr *ia_a = (struct dhcpv6_ia_addr *)&odata[-4];
+			bool found = false;
+
+			if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*ia_p) - 4) &&
+					(otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*ia_a) - 4))
+				continue;
+
+			if (a) {
+				struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->addr6;
+				size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->addr6_len;
+
+				for (size_t i = 0; i < addrlen; ++i) {
+					if (!valid_addr(&addrs[i], now))
+						continue;
+
+					struct in6_addr addr = addrs[i].addr.in6;
+					if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
+						addr.s6_addr32[1] |= htonl(a->assigned);
+						addr.s6_addr32[2] = addr.s6_addr32[3] = 0;
+
+						if (!memcmp(&ia_p->addr, &addr, sizeof(addr)) &&
+								ia_p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
+							found = true;
 					} else {
-						struct dhcpv6_ia_addr inv = {
-							.type = htons(DHCPV6_OPT_IA_ADDR),
-							.len = htons(sizeof(inv) - 4),
-							.addr = n->addr,
-							.preferred = 0,
-							.valid = 0
-						};
-
-						if (datalen + sizeof(inv) > buflen)
-							continue;
-
-						memcpy(buf + datalen, &inv, sizeof(inv));
-						datalen += sizeof(inv);
+						addr.s6_addr32[3] = htonl(a->assigned);
+
+						if (!memcmp(&ia_a->addr, &addr, sizeof(addr)))
+							found = true;
 					}
 				}
 			}
+
+			if (!found) {
+				if (otype == DHCPV6_OPT_IA_PREFIX) {
+					struct dhcpv6_ia_prefix o_ia_p = {
+						.type = htons(DHCPV6_OPT_IA_PREFIX),
+						.len = htons(sizeof(o_ia_p) - 4),
+						.preferred = 0,
+						.valid = 0,
+						.prefix = ia_p->prefix,
+						.addr = ia_p->addr,
+					};
+
+					if (buflen < ia_len + sizeof(o_ia_p))
+						return 0;
+
+					memcpy(buf + ia_len, &o_ia_p, sizeof(o_ia_p));
+					ia_len += sizeof(o_ia_p);
+				} else {
+					struct dhcpv6_ia_addr o_ia_a = {
+						.type = htons(DHCPV6_OPT_IA_ADDR),
+						.len = htons(sizeof(o_ia_a) - 4),
+						.addr = ia_a->addr,
+						.preferred = 0,
+						.valid = 0,
+					};
+
+					if (buflen < ia_len + sizeof(o_ia_a))
+						continue;
+
+					memcpy(buf + ia_len, &o_ia_a, sizeof(o_ia_a));
+					ia_len += sizeof(o_ia_a);
+				}
+			}
 		}
 	}
 
-	out.len = htons(datalen - 4);
-	memcpy(buf, &out, sizeof(out));
-	return datalen;
+	o_ia.len = htons(ia_len - 4);
+	memcpy(buf, &o_ia, sizeof(o_ia));
+	return ia_len;
+}
+
+struct log_ctxt {
+	char *buf;
+	int buf_len;
+	int buf_idx;
+};
+
+static void dhcpv6_log_ia_addr(struct in6_addr *addr, int prefix, _unused uint32_t pref,
+				_unused uint32_t valid, void *arg)
+{
+	struct log_ctxt *ctxt = (struct log_ctxt *)arg;
+	char addrbuf[INET6_ADDRSTRLEN];
+
+	inet_ntop(AF_INET6, addr, addrbuf, sizeof(addrbuf));
+	ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx, ctxt->buf_len - ctxt->buf_idx,
+					"%s/%d ", addrbuf, prefix);
 }
 
 static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
-		const char *duidbuf, bool is_pd, struct dhcpv6_assignment *a, int code)
+		const char *duidbuf, bool is_pd, struct dhcp_assignment *a, int code)
 {
 	const char *type = "UNKNOWN";
 	const char *status = "UNKNOWN";
 
-	if (msgtype == DHCPV6_MSG_RENEW)
-		return;
-
 	switch (msgtype) {
 	case DHCPV6_MSG_SOLICIT:
 		type = "SOLICIT";
@@ -923,32 +1105,59 @@ static void dhcpv6_log(uint8_t msgtype, struct interface *iface, time_t now,
 	char leasebuf[256] = "";
 
 	if (a) {
-		struct odhcpd_ipaddr *addrs = (a->managed) ? a->managed : iface->ia_addr;
-		size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
-		size_t lbsize = 0;
-		char addrbuf[INET6_ADDRSTRLEN];
+		struct log_ctxt ctxt = {.buf = leasebuf,
+					.buf_len = sizeof(leasebuf),
+					.buf_idx = 0 };
+
+		dhcpv6_ia_enum_addrs(iface, a, now, dhcpv6_log_ia_addr, &ctxt);
+	}
+
+	syslog(LOG_WARNING, "DHCPV6 %s %s from %s on %s: %s %s", type, (is_pd) ? "IA_PD" : "IA_NA",
+			duidbuf, iface->name, status, leasebuf);
+}
+
+static bool dhcpv6_ia_on_link(const struct dhcpv6_ia_hdr *ia, struct dhcp_assignment *a,
+		struct interface *iface)
+{
+	struct odhcpd_ipaddr *addrs = (a && a->managed) ? a->managed : iface->addr6;
+	size_t addrlen = (a && a->managed) ? (size_t)a->managed_size : iface->addr6_len;
+	time_t now = odhcpd_time();
+	uint8_t *odata, *end = ((uint8_t*)ia) + htons(ia->len) + 4;
+	uint16_t otype, olen;
+	bool onlink = true;
+
+	dhcpv6_for_each_option((uint8_t*)&ia[1], end, otype, olen, odata) {
+		struct dhcpv6_ia_prefix *p = (struct dhcpv6_ia_prefix *)&odata[-4];
+		struct dhcpv6_ia_addr *n = (struct dhcpv6_ia_addr *)&odata[-4];
+
+		if ((otype != DHCPV6_OPT_IA_PREFIX || olen < sizeof(*p) - 4) &&
+				(otype != DHCPV6_OPT_IA_ADDR || olen < sizeof(*n) - 4))
+			continue;
 
+		onlink = false;
 		for (size_t i = 0; i < addrlen; ++i) {
 			if (!valid_addr(&addrs[i], now))
 				continue;
 
-			struct in6_addr addr = addrs[i].addr;
-			int prefix = a->managed ? addrs[i].prefix : a->length;
-			if (prefix == 128)
-				addr.s6_addr32[3] = htonl(a->assigned);
-			else
-				addr.s6_addr32[1] |= htonl(a->assigned);
+			if (ia->type == htons(DHCPV6_OPT_IA_PD)) {
+				if (p->prefix < addrs[i].prefix ||
+				    odhcpd_bmemcmp(&p->addr, &addrs[i].addr.in6, addrs[i].prefix))
+					continue;
+
+			} else if (odhcpd_bmemcmp(&n->addr, &addrs[i].addr.in6, addrs[i].prefix))
+				continue;
 
-			inet_ntop(AF_INET6, &addr, addrbuf, sizeof(addrbuf));
-			lbsize += snprintf(leasebuf + lbsize, sizeof(leasebuf) - lbsize, "%s/%d ", addrbuf, prefix);
+			onlink = true;
 		}
+
+		if (!onlink)
+			break;
 	}
 
-	syslog(LOG_WARNING, "DHCPV6 %s %s from %s on %s: %s %s", type, (is_pd) ? "IA_PD" : "IA_NA",
-			duidbuf, iface->ifname, status, leasebuf);
+	return onlink;
 }
 
-ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
+ssize_t dhcpv6_ia_handle_IAs(uint8_t *buf, size_t buflen, struct interface *iface,
 		const struct sockaddr_in6 *addr, const void *data, const uint8_t *end)
 {
 	time_t now = odhcpd_time();
@@ -961,7 +1170,7 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 	uint8_t *clid_data = NULL, clid_len = 0, mac[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 	char hostname[256];
 	size_t hostname_len = 0;
-	bool notonlink = false;
+	bool notonlink = false, rapid_commit = false;
 	char duidbuf[261];
 
 	dhcpv6_for_each_option(start, end, otype, olen, odata) {
@@ -985,12 +1194,14 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 				hostname_len = strcspn(hostname, ".");
 		} else if (otype == DHCPV6_OPT_RECONF_ACCEPT)
 			accept_reconf = true;
+		else if (otype == DHCPV6_OPT_RAPID_COMMIT && hdr->msg_type == DHCPV6_MSG_SOLICIT)
+			rapid_commit = true;
 	}
 
 	if (!clid_data || !clid_len || clid_len > 130)
 		goto out;
 
-	struct dhcpv6_assignment *first = NULL;
+	struct dhcp_assignment *first = NULL;
 	dhcpv6_for_each_option(start, end, otype, olen, odata) {
 		bool is_pd = (otype == DHCPV6_OPT_IA_PD);
 		bool is_na = (otype == DHCPV6_OPT_IA_NA);
@@ -1034,23 +1245,25 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 		}
 
 		/* Find assignment */
-		struct dhcpv6_assignment *c, *a = NULL;
+		struct dhcp_assignment *c, *a = NULL;
 		list_for_each_entry(c, &iface->ia_assignments, head) {
 			if (((c->clid_len == clid_len && !memcmp(c->clid_data, clid_data, clid_len)) ||
 					(c->clid_len >= clid_len && !c->clid_data[0] && !c->clid_data[1]
 						&& !memcmp(c->mac, mac, sizeof(mac)))) &&
-					(c->iaid == ia->iaid || INFINITE_VALID(c->valid_until) || now < c->valid_until) &&
+					(!(c->flags & (OAF_BOUND|OAF_TENTATIVE)) || c->iaid == ia->iaid) &&
+					(INFINITE_VALID(c->valid_until) || now < c->valid_until) &&
 					((is_pd && c->length <= 64) || (is_na && c->length == 128))) {
 				a = c;
 
-				// Reset state
-				apply_lease(iface, a, false);
+				/* Reset state */
+				if (a->flags & OAF_BOUND)
+					apply_lease(iface, a, false);
+
 				memcpy(a->clid_data, clid_data, clid_len);
 				a->clid_len = clid_len;
 				a->iaid = ia->iaid;
 				a->peer = *addr;
-				a->reconf_cnt = 0;
-				a->reconf_sent = 0;
+				stop_reconf(a);
 				break;
 			}
 		}
@@ -1060,10 +1273,12 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 		if (a && a->managed_size < 0)
 			return -1;
 
-		if (hdr->msg_type == DHCPV6_MSG_SOLICIT || hdr->msg_type == DHCPV6_MSG_REQUEST) {
+		if (hdr->msg_type == DHCPV6_MSG_SOLICIT ||
+				hdr->msg_type == DHCPV6_MSG_REQUEST ||
+				(hdr->msg_type == DHCPV6_MSG_REBIND && !a)) {
 			bool assigned = !!a;
 
-			if (!a && !iface->no_dynamic_dhcp) {
+			if (!a && !iface->no_dynamic_dhcp && (iface->dhcpv6_pd || iface->dhcpv6_na)) {
 				/* Create new binding */
 				a = calloc(1, sizeof(*a) + clid_len);
 				if (a) {
@@ -1075,6 +1290,7 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 					/* Set valid time to current time indicating  */
 					/* assignment is not having infinite lifetime */
 					a->valid_until = now;
+					a->iface = iface;
 
 					if (first)
 						memcpy(a->key, first->key, sizeof(a->key));
@@ -1082,10 +1298,10 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 						odhcpd_urandom(a->key, sizeof(a->key));
 					memcpy(a->clid_data, clid_data, clid_len);
 
-					if (is_pd)
+					if (is_pd && iface->dhcpv6_pd)
 						while (!(assigned = assign_pd(iface, a)) &&
 								!a->managed_size && ++a->length <= 64);
-					else
+					else if (is_na && iface->dhcpv6_na)
 						assigned = assign_na(iface, a);
 
 					if (a->managed_size && !assigned)
@@ -1093,10 +1309,15 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 				}
 			}
 
-			if (!assigned || iface->ia_addr_len == 0)
+			if (!assigned || iface->addr6_len == 0)
 				/* Set error status */
 				status = (is_pd) ? DHCPV6_STATUS_NOPREFIXAVAIL : DHCPV6_STATUS_NOADDRSAVAIL;
-			else if (assigned && !first) {
+			else if (hdr->msg_type == DHCPV6_MSG_REQUEST && !dhcpv6_ia_on_link(ia, a, iface)) {
+				/* Send NOTONLINK staus for the IA */
+				status = DHCPV6_STATUS_NOTONLINK;
+				assigned = false;
+			} else if (accept_reconf && assigned && !first &&
+					hdr->msg_type != DHCPV6_MSG_REBIND) {
 				size_t handshake_len = 4;
 				buf[0] = 0;
 				buf[1] = DHCPV6_OPT_RECONF_ACCEPT;
@@ -1117,6 +1338,7 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 					handshake_len += sizeof(auth);
 				}
 
+
 				buf += handshake_len;
 				buflen -= handshake_len;
 				response_len += handshake_len;
@@ -1124,39 +1346,53 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 				first = a;
 			}
 
-			ia_response_len = append_reply(buf, buflen, status, ia, a, iface, true);
+			ia_response_len = build_ia(buf, buflen, status, ia, a, iface,
+							hdr->msg_type == DHCPV6_MSG_REBIND ? false : true);
 
 			/* Was only a solicitation: mark binding for removal */
-			if (assigned && hdr->msg_type == DHCPV6_MSG_SOLICIT) {
+			if (assigned && hdr->msg_type == DHCPV6_MSG_SOLICIT && !rapid_commit) {
 				a->flags &= ~OAF_BOUND;
+				a->flags |= OAF_TENTATIVE;
 
 				if (!(a->flags & OAF_STATIC))
-					a->valid_until = now;
-			} else if (assigned && hdr->msg_type == DHCPV6_MSG_REQUEST) {
+					/* Keep tentative assignment around for 60 seconds */
+					a->valid_until = now + 60;
+
+			} else if (assigned &&
+				   ((hdr->msg_type == DHCPV6_MSG_SOLICIT && rapid_commit) ||
+				    hdr->msg_type == DHCPV6_MSG_REQUEST ||
+				    hdr->msg_type == DHCPV6_MSG_REBIND)) {
 				if (hostname_len > 0) {
 					a->hostname = realloc(a->hostname, hostname_len + 1);
 					if (a->hostname) {
 						memcpy(a->hostname, hostname, hostname_len);
 						a->hostname[hostname_len] = 0;
+
+						if (odhcpd_valid_hostname(a->hostname))
+							a->flags &= ~OAF_BROKEN_HOSTNAME;
+						else
+							a->flags |= OAF_BROKEN_HOSTNAME;
 					}
 				}
 				a->accept_reconf = accept_reconf;
+				a->flags &= ~OAF_TENTATIVE;
 				a->flags |= OAF_BOUND;
 				apply_lease(iface, a, true);
-			} else if (!assigned && a && a->managed_size == 0)
+			} else if (!assigned && a && a->managed_size == 0) {
 				/* Cleanup failed assignment */
 				free_dhcpv6_assignment(a);
-
+				a = NULL;
+			}
 		} else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
 				hdr->msg_type == DHCPV6_MSG_RELEASE ||
 				hdr->msg_type == DHCPV6_MSG_REBIND ||
 				hdr->msg_type == DHCPV6_MSG_DECLINE) {
 			if (!a && hdr->msg_type != DHCPV6_MSG_REBIND) {
 				status = DHCPV6_STATUS_NOBINDING;
-				ia_response_len = append_reply(buf, buflen, status, ia, a, iface, false);
+				ia_response_len = build_ia(buf, buflen, status, ia, a, iface, false);
 			} else if (hdr->msg_type == DHCPV6_MSG_RENEW ||
 					hdr->msg_type == DHCPV6_MSG_REBIND) {
-				ia_response_len = append_reply(buf, buflen, status, ia, a, iface, false);
+				ia_response_len = build_ia(buf, buflen, status, ia, a, iface, false);
 				if (a) {
 					a->flags |= OAF_BOUND;
 					apply_lease(iface, a, true);
@@ -1165,8 +1401,10 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 				if (!(a->flags & OAF_STATIC))
 					a->valid_until = now - 1;
 
-				a->flags &= ~OAF_BOUND;
-				apply_lease(iface, a, false);
+				if (a->flags & OAF_BOUND) {
+					apply_lease(iface, a, false);
+					a->flags &= ~OAF_BOUND;
+				}
 			} else if (hdr->msg_type == DHCPV6_MSG_DECLINE && a->length == 128) {
 				a->flags &= ~OAF_BOUND;
 
@@ -1175,11 +1413,16 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 					a->valid_until = now + 3600; /* Block address for 1h */
 				}
 			}
-		} else if (hdr->msg_type == DHCPV6_MSG_CONFIRM && ia_addr_present) {
-			/* Send NOTONLINK for CONFIRM with addr present so that clients restart connection */
-			status = DHCPV6_STATUS_NOTONLINK;
-			ia_response_len = append_reply(buf, buflen, status, ia, a, iface, true);
-			notonlink = true;
+		} else if (hdr->msg_type == DHCPV6_MSG_CONFIRM) {
+			if (ia_addr_present && !dhcpv6_ia_on_link(ia, a, iface)) {
+				notonlink = true;
+				break;
+			}
+
+			if (!ia_addr_present || !a || !(a->flags & OAF_BOUND)) {
+				response_len = 0;
+				goto out;
+			}
 		}
 
 		buf += ia_response_len;
@@ -1188,18 +1431,26 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 		dhcpv6_log(hdr->msg_type, iface, now, duidbuf, is_pd, a, status);
 	}
 
-	if ((hdr->msg_type == DHCPV6_MSG_RELEASE || hdr->msg_type == DHCPV6_MSG_DECLINE || notonlink) &&
-			response_len + 6 < buflen) {
-		buf[0] = 0;
-		buf[1] = DHCPV6_OPT_STATUS;
-		buf[2] = 0;
-		buf[3] = 2;
-		buf[4] = 0;
-		buf[5] = (notonlink) ? DHCPV6_STATUS_NOTONLINK : DHCPV6_STATUS_OK;
-		response_len += 6;
+	switch (hdr->msg_type) {
+	case DHCPV6_MSG_RELEASE:
+	case DHCPV6_MSG_DECLINE:
+	case DHCPV6_MSG_CONFIRM:
+		if (response_len + 6 < buflen) {
+			buf[0] = 0;
+			buf[1] = DHCPV6_OPT_STATUS;
+			buf[2] = 0;
+			buf[3] = 2;
+			buf[4] = 0;
+			buf[5] = (notonlink) ? DHCPV6_STATUS_NOTONLINK : DHCPV6_STATUS_OK;
+			response_len += 6;
+		}
+		break;
+
+	default:
+		break;
 	}
 
-	dhcpv6_write_statefile();
+	dhcpv6_ia_write_statefile();
 
 out:
 	return response_len;