ubus: fix invalid ipv6-prefix json
[project/odhcpd.git] / src / dhcpv6-ia.c
index c8786c3..e94dc38 100644 (file)
@@ -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>
 #include <arpa/inet.h>
 #include <sys/timerfd.h>
 
+#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 dhcpv6_assignment *c);
-static void reconf_timer(struct uloop_timeout *event);
-static struct uloop_timeout reconf_event = {.cb = reconf_timer};
+static void handle_addrlist_change(struct netevent_handler_info *info);
+static void start_reconf(struct dhcpv6_assignment *a);
+static void stop_reconf(struct dhcpv6_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_setup_ia_interface(struct interface *iface, bool enable)
 {
        if (!enable && iface->ia_assignments.next) {
                struct dhcpv6_assignment *c;
+
                while (!list_empty(&iface->ia_assignments)) {
                        c = list_first_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
                        free_dhcpv6_assignment(c);
                }
        }
 
-       if (enable && iface->dhcpv6 == RELAYD_SERVER) {
+       if (enable && iface->dhcpv6 == MODE_SERVER) {
                if (!iface->ia_assignments.next)
                        INIT_LIST_HEAD(&iface->ia_assignments);
 
@@ -83,8 +98,7 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
                                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;
@@ -103,7 +117,7 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
                        /* Infinite valid */
                        a->valid_until = 0;
 
-                       // Assign to all interfaces
+                       /* Assign to all interfaces */
                        struct dhcpv6_assignment *c;
                        list_for_each_entry(c, &iface->ia_assignments, head) {
                                if (c->length != 128 || c->assigned > a->assigned) {
@@ -115,6 +129,7 @@ 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);
@@ -126,6 +141,24 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
        return 0;
 }
 
+
+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 dhcpv6_assignment *c)
 {
        if (c->managed_sock.fd.registered) {
@@ -136,31 +169,39 @@ 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 dhcpv6_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 dhcpv6_assignment *assign)
 {
        struct {
                struct dhcpv6_client_header hdr;
@@ -192,6 +233,7 @@ 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);
@@ -223,139 +265,196 @@ 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_enum_ia_addrs(struct interface *iface, struct dhcpv6_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 dhcpv6_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) {
+               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_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);
+
+               list_for_each_entry(ctxt.iface, &interfaces, head) {
+                       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);
+                                       odhcpd_hexlify(duidbuf, ctxt.c->clid_data, ctxt.c->clid_len);
 
-                                               inet_ntop(AF_INET6, &addr, ipbuf, sizeof(ipbuf) - 1);
+                                       /* iface DUID iaid hostname lifetime assigned length [addrs...] */
+                                       ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s %x %s %ld %x %u ",
+                                                               ctxt.iface->ifname, duidbuf, ntohl(ctxt.c->iaid),
+                                                               (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 (c->length == 128 && c->hostname) {
-                                                       fputs(ipbuf, fp);
+                                       if (INFINITE_VALID(ctxt.c->valid_until) || ctxt.c->valid_until > now)
+                                               dhcpv6_enum_ia_addrs(ctxt.iface, ctxt.c, now,
+                                                                       dhcpv6_write_ia_addr, &ctxt);
 
-                                                       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);
+                                       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) {
+                       if (ctxt.iface->dhcpv4 == MODE_SERVER &&
+                                       ctxt.iface->dhcpv4_assignments.next) {
                                struct dhcpv4_assignment *c;
-                               list_for_each_entry(c, &iface->dhcpv4_assignments, head) {
+                               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);
+                                       /* iface DUID iaid hostname lifetime assigned length [addrs...] */
+                                       ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s ipv4 %s %ld %x 32 ",
+                                                               ctxt.iface->ifname, duidbuf,
+                                                               (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 = {htonl(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);
+                                               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));
@@ -367,24 +466,30 @@ 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 dhcpv6_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);
        }
 }
 
-// More data was received from TCP connection
+static void apply_lease(struct interface *iface, struct dhcpv6_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);
+}
+
+/* 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);
@@ -450,7 +555,7 @@ 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;
 }
 
@@ -502,7 +607,7 @@ 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 */
@@ -514,7 +619,10 @@ 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;
                        }
 
@@ -533,7 +641,10 @@ 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;
                }
 
@@ -574,42 +685,33 @@ 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(
+       struct interface *iface = info->iface;
+       struct dhcpv6_assignment *c, *d, *border = list_last_entry(
                        &iface->ia_assignments, struct dhcpv6_assignment, head);
+       time_t now = odhcpd_time();
+       int minprefix = -1;
 
        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;
-
-       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;
+               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);
+
+       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;
        }
 
-       struct dhcpv6_assignment *border = list_last_entry(
-                       &iface->ia_assignments, struct dhcpv6_assignment, head);
-
        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)
@@ -617,20 +719,18 @@ 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);
+                       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;
                }
        }
 
@@ -646,12 +746,42 @@ void dhcpv6_ia_postupdate(struct interface *iface, time_t now)
        dhcpv6_write_statefile();
 }
 
-static void reconf_timer(struct uloop_timeout *event)
+static void reconf_timeout_cb(struct uloop_timeout *event)
+{
+       struct dhcpv6_assignment *a = container_of(event, struct dhcpv6_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 dhcpv6_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 dhcpv6_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)
+               if (iface->dhcpv6 != MODE_SERVER || iface->ia_assignments.next == NULL)
                        continue;
 
                struct dhcpv6_assignment *a, *n;
@@ -661,15 +791,10 @@ static void reconf_timer(struct uloop_timeout *event)
                                                (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,
@@ -696,22 +821,17 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
        } else {
                if (a) {
                        uint32_t leasetime;
-                       if (a->leasetime > 0)
+                       if (a->leasetime)
                                leasetime = a->leasetime;
                        else
                                leasetime = iface->dhcpv4_leasetime;
 
-                       if (leasetime == 0)
-                               leasetime = 3600;
-                       else if (leasetime < 60)
-                               leasetime = 60;
-
                        uint32_t pref = leasetime;
                        uint32_t valid = leasetime;
 
-                       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);
+                       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);
 
                        for (size_t i = 0; i < addrlen; ++i) {
                                uint32_t prefix_pref = addrs[i].preferred;
@@ -733,15 +853,16 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                                                .preferred = htonl(prefix_pref),
                                                .valid = htonl(prefix_valid),
                                                .prefix = (a->managed_size) ? addrs[i].prefix : a->length,
-                                               .addr = addrs[i].addr
+                                               .addr = addrs[i].addr.in6,
                                        };
                                        p.addr.s6_addr32[1] |= htonl(a->assigned);
+                                       p.addr.s6_addr32[2] = p.addr.s6_addr32[3] = 0;
 
                                        size_t entrlen = sizeof(p) - 4;
 
                                        if (datalen + entrlen + 4 > buflen ||
                                                        (a->assigned == 0 && a->managed_size == 0) ||
-                                                       (!a->managed_size && a->length <= addrs[i].prefix))
+                                                       !valid_prefix_length(a, addrs[i].prefix))
                                                continue;
 
                                        memcpy(buf + datalen, &p, sizeof(p));
@@ -750,18 +871,16 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                                        struct dhcpv6_ia_addr n = {
                                                .type = htons(DHCPV6_OPT_IA_ADDR),
                                                .len = htons(sizeof(n) - 4),
-                                               .addr = addrs[i].addr,
+                                               .addr = addrs[i].addr.in6,
                                                .preferred = htonl(prefix_pref),
                                                .valid = htonl(prefix_valid)
                                        };
                                        n.addr.s6_addr32[3] = htonl(a->assigned);
                                        size_t entrlen = sizeof(n) - 4;
 
-                                       if (iface->managed < RELAYD_MANAGED_NO_AFLAG && i != m &&
-                                                       addrs[i].prefix <= 64)
-                                               continue;
-
-                                       if (datalen + entrlen + 4 > buflen || a->assigned == 0)
+                                       if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) ||
+                                                       a->assigned == 0 ||
+                                                       datalen + entrlen + 4 > buflen)
                                                continue;
 
                                        memcpy(buf + datalen, &n, sizeof(n));
@@ -804,16 +923,17 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
 
                                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;
+                                       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;
+                                               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(&p->addr, &addr, sizeof(addr)) &&
                                                                        p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
@@ -868,6 +988,23 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
        return datalen;
 }
 
+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)
 {
@@ -922,25 +1059,11 @@ 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];
-
-               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);
+               struct log_ctxt ctxt = {.buf = leasebuf,
+                                       .buf_len = sizeof(leasebuf),
+                                       .buf_idx = 0 };
 
-                       inet_ntop(AF_INET6, &addr, addrbuf, sizeof(addrbuf));
-                       lbsize += snprintf(leasebuf + lbsize, sizeof(leasebuf) - lbsize, "%s/%d ", addrbuf, prefix);
-               }
+               dhcpv6_enum_ia_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",
@@ -1037,19 +1160,21 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                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) &&
+                                               && !memcmp(c->mac, mac, sizeof(mac)))) &&
+                                       (!(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;
                        }
                }
@@ -1059,7 +1184,9 @@ 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) {
@@ -1074,6 +1201,7 @@ 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));
@@ -1092,10 +1220,11 @@ 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 (accept_reconf && assigned && !first &&
+                                       hdr->msg_type != DHCPV6_MSG_REBIND) {
                                size_t handshake_len = 4;
                                buf[0] = 0;
                                buf[1] = DHCPV6_OPT_RECONF_ACCEPT;
@@ -1123,15 +1252,20 @@ 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 = append_reply(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) {
                                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_REQUEST ||
+                                        hdr->msg_type == DHCPV6_MSG_REBIND)) {
                                if (hostname_len > 0) {
                                        a->hostname = realloc(a->hostname, hostname_len + 1);
                                        if (a->hostname) {
@@ -1140,12 +1274,14 @@ ssize_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                                        }
                                }
                                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 ||
@@ -1164,8 +1300,10 @@ 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;