dhcpv6-ia: apply lease delete based on assignment bound state
[project/odhcpd.git] / src / dhcpv6-ia.c
index 593b5bd..84f368e 100644 (file)
@@ -1,5 +1,6 @@
 /**
  * Copyright (C) 2013 Steven Barth <steven@midlink.org>
+ * Copyright (C) 2016 Hans Dedecker <dedeckeh@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License v2 as published by
@@ -22,6 +23,7 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <stdio.h>
+#include <poll.h>
 #include <alloca.h>
 #include <resolv.h>
 #include <limits.h>
 #include <arpa/inet.h>
 #include <sys/timerfd.h>
 
+#define ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) \
+    ((iface)->managed == RELAYD_MANAGED_NO_AFLAG || (i) == (m) || \
+     (addrs)[(i)].prefix > 64)
 
-static void update(struct interface *iface);
+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 uint32_t serial = 0;
 static uint8_t statemd5[16];
 
-
 int dhcpv6_ia_init(void)
 {
        uloop_timeout_set(&reconf_event, 2000);
        return 0;
 }
 
-
-void free_dhcpv6_assignment(struct dhcpv6_assignment *c)
-{
-       if (c->managed_sock.fd.registered) {
-               close(c->managed_sock.fd.fd);
-               ustream_free(&c->managed_sock.stream);
-       }
-
-       free(c->managed);
-       free(c->hostname);
-       free(c->classes);
-       free(c);
-}
-
-
 int setup_dhcpv6_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);
-                       list_del(&c->head);
                        free_dhcpv6_assignment(c);
                }
        }
 
-       if (iface->dhcpv6 == RELAYD_SERVER) {
+       if (enable && iface->dhcpv6 == RELAYD_SERVER) {
                if (!iface->ia_assignments.next)
                        INIT_LIST_HEAD(&iface->ia_assignments);
 
@@ -82,25 +71,27 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
                                syslog(LOG_ERR, "Calloc failed for border on interface %s", iface->ifname);
                                return -1;
                        }
-                       
+
                        border->length = 64;
                        list_add(&border->head, &iface->ia_assignments);
                }
 
-               update(iface);
-
-               // Parse static entries
+               /* Parse static entries */
                struct lease *lease;
                list_for_each_entry(lease, &leases, head) {
-                       // Construct entry
-                       struct dhcpv6_assignment *a = calloc(1, sizeof(*a) + lease->duid_len);
+                       /* Construct entry */
+                       size_t duid_len = lease->duid_len ? lease->duid_len : 14;
+                       struct dhcpv6_assignment *a = calloc(1, sizeof(*a) + duid_len);
                        if (!a) {
                                syslog(LOG_ERR, "Calloc failed for static lease assignment on interface %s",
                                        iface->ifname);
                                return -1;
                        }
 
-                       a->clid_len = lease->duid_len;
+                       if (lease->dhcpv4_leasetime > 0)
+                               a->leasetime = lease->dhcpv4_leasetime;
+
+                       a->clid_len = duid_len;
                        a->length = 128;
                        if (lease->hostid) {
                                a->assigned = lease->hostid;
@@ -108,20 +99,24 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
                                uint32_t i4a = ntohl(lease->ipaddr.s_addr) & 0xff;
                                a->assigned = ((i4a / 100) << 8) | (((i4a % 100) / 10) << 4) | (i4a % 10);
                        }
+
                        odhcpd_urandom(a->key, sizeof(a->key));
-                       memcpy(a->clid_data, lease->duid, a->clid_len);
+                       memcpy(a->clid_data, lease->duid, lease->duid_len);
                        memcpy(a->mac, lease->mac.ether_addr_octet, sizeof(a->mac));
+                       /* Static assignment */
+                       a->flags |= OAF_STATIC;
+                       /* 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) {
                                        list_add_tail(&a->head, &c->head);
                                        break;
-                               } else if (c->assigned == a->assigned) {
-                                       // Already an assignment with that number
+                               } else if (c->assigned == a->assigned)
+                                       /* Already an assignment with that number */
                                        break;
-                               }
                        }
 
                        if (a->head.next) {
@@ -129,16 +124,51 @@ int setup_dhcpv6_ia_interface(struct interface *iface, bool enable)
                                        free(a->hostname);
                                        a->hostname = strdup(lease->hostname);
                                }
-                       } else {
-                               free(a->classes);
-                               free(a->hostname);
-                               free(a);
-                       }
+                       } else
+                               free_dhcpv6_assignment(a);
                }
        }
        return 0;
 }
 
+static void free_dhcpv6_assignment(struct dhcpv6_assignment *c)
+{
+       if (c->managed_sock.fd.registered) {
+               ustream_free(&c->managed_sock.stream);
+               close(c->managed_sock.fd.fd);
+       }
+
+       if (c->head.next)
+               list_del(&c->head);
+
+       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)
+{
+       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))
+                       m = i;
+       }
+
+       return m;
+}
 
 static int send_reconf(struct interface *iface, struct dhcpv6_assignment *assign)
 {
@@ -203,7 +233,6 @@ 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)
 {
        md5_ctx_t md5;
@@ -216,7 +245,7 @@ void dhcpv6_write_statefile(void)
                        return;
 
                lockf(fd, F_LOCK, 0);
-               ftruncate(fd, 0);
+               if (ftruncate(fd, 0) < 0) {}
 
                FILE *fp = fdopen(fd, "w");
                if (!fp) {
@@ -232,7 +261,7 @@ void dhcpv6_write_statefile(void)
                        if (iface->dhcpv6 == RELAYD_SERVER && iface->ia_assignments.next) {
                                struct dhcpv6_assignment *c;
                                list_for_each_entry(c, &iface->ia_assignments, head) {
-                                       if (c->clid_len == 0 || c->managed_size < 0)
+                                       if (!(c->flags & OAF_BOUND) || c->managed_size < 0)
                                                continue;
 
                                        char ipbuf[INET6_ADDRSTRLEN];
@@ -240,44 +269,55 @@ void dhcpv6_write_statefile(void)
                                        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 %u %x %u ",
+                                       /* 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 : "-"),
-                                                       (unsigned)(c->valid_until > now ?
-                                                                       (c->valid_until - now + wall_time) : 0),
+                                                       (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 (addrs[i].prefix > 96)
+                                               if (!valid_addr(&addrs[i], now) ||
+                                                           (!INFINITE_VALID(c->valid_until) && c->valid_until <= now))
                                                        continue;
 
                                                addr = addrs[i].addr;
-                                               if (c->length == 128)
+                                               if (c->length == 128) {
+                                                       if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs))
+                                                               continue;
+
                                                        addr.s6_addr32[3] = htonl(c->assigned);
-                                               else
+                                               }
+                                               else {
+                                                       if (!valid_prefix_length(c, addrs[i].prefix))
+                                                               continue;
+
                                                        addr.s6_addr32[1] |= htonl(c->assigned);
+                                               }
 
                                                inet_ntop(AF_INET6, &addr, ipbuf, sizeof(ipbuf) - 1);
 
-                                               if (c->length == 128 && c->hostname && i == 0) {
+                                               if (c->length == 128 && c->hostname) {
                                                        fputs(ipbuf, 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);
+                                                       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/%hhu ", ipbuf,
+                                               l += snprintf(leasebuf + l, sizeof(leasebuf) - l, "%s/%d ", ipbuf,
                                                                (c->managed_size) ? addrs[i].prefix : c->length);
                                        }
                                        leasebuf[l - 1] = '\n';
@@ -288,29 +328,33 @@ void dhcpv6_write_statefile(void)
                        if (iface->dhcpv4 == RELAYD_SERVER && iface->dhcpv4_assignments.next) {
                                struct dhcpv4_assignment *c;
                                list_for_each_entry(c, &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 %u %x 32 ",
+                                       /* 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 : "-"),
-                                                       (unsigned)(c->valid_until > now ?
-                                                                       (c->valid_until - now + wall_time) : 0),
+                                                       (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)};
                                        inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
 
-                                       if (c->hostname[0]) {
+                                       if (c->hostname) {
                                                fputs(ipbuf, 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);
+                                               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);
@@ -353,12 +397,11 @@ static void apply_lease(struct interface *iface, struct dhcpv6_assignment *a, bo
                struct in6_addr prefix = addrs[i].addr;
                prefix.s6_addr32[1] |= htonl(a->assigned);
                odhcpd_setup_route(&prefix, (a->managed_size) ? addrs[i].prefix : a->length,
-                               iface, &a->peer.sin6_addr, add);
+                               iface, &a->peer.sin6_addr, 1024, add);
        }
 }
 
-
-// More data was received from TCP connection
+/* 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);
@@ -401,8 +444,20 @@ static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
                        if (sscanf(x, "%u", &n->valid) < 1)
                                continue;
 
-                       n->preferred += now;
-                       n->valid += now;
+                       if (n->preferred > n->valid)
+                               continue;
+
+                       if (UINT32_MAX - now < n->preferred)
+                               n->preferred = UINT32_MAX;
+                       else
+                               n->preferred += now;
+
+                       if (UINT32_MAX - now < n->valid)
+                               n->valid = UINT32_MAX;
+                       else
+                               n->valid += now;
+
+                       n->dprefix = 0;
 
                        ++c->managed_size;
                }
@@ -410,25 +465,27 @@ static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
                ustream_consume(s, end - data);
        }
 
-       if (first && c->managed_size == 0) {
-               list_del(&c->head);
+       if (first && c->managed_size == 0)
                free_dhcpv6_assignment(c);
-       }
+       else if (first && !(c->flags & OAF_STATIC))
+               c->valid_until = now + 150;
 }
 
 
-// TCP transmission has ended, either because of success or timeout or other error
+/* 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);
-       c->valid_until = odhcpd_time() + 15;
+
+       if (!(c->flags & OAF_STATIC))
+               c->valid_until = odhcpd_time() + 15;
+
        c->managed_size = 0;
+
        if (c->accept_reconf)
                c->reconf_cnt = 1;
 }
 
-
-
 static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
 {
        struct dhcpv6_assignment *c;
@@ -436,21 +493,36 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
        if (iface->dhcpv6_pd_manager[0]) {
                int fd = usock(USOCK_UNIX | USOCK_TCP, iface->dhcpv6_pd_manager, NULL);
                if (fd >= 0) {
+                       char iaidbuf[298];
+                       odhcpd_hexlify(iaidbuf, assign->clid_data, assign->clid_len);
+
                        assign->managed_sock.stream.notify_read = managed_handle_pd_data;
                        assign->managed_sock.stream.notify_state = managed_handle_pd_done;
                        ustream_fd_init(&assign->managed_sock, fd);
-                       ustream_printf(&assign->managed_sock.stream, "::/%d,0,0\n\n", assign->length);
+                       ustream_printf(&assign->managed_sock.stream, "%s,%x\n::/%d,0,0\n\n",
+                                       iaidbuf, assign->iaid, assign->length);
                        ustream_write_pending(&assign->managed_sock.stream);
                        assign->managed_size = -1;
+
+                       if (!(assign->flags & OAF_STATIC))
+                               assign->valid_until = odhcpd_time() + 15;
+
                        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);
+                       managed_handle_pd_data(&assign->managed_sock.stream, 0);
+
+                       if (fcntl(fd, F_GETFL) >= 0 && assign->managed_size > 0)
+                               return true;
                }
 
                return false;
-       } else if (iface->ia_addr_len < 1) {
+       } else if (iface->ia_addr_len < 1)
                return false;
-       }
 
-       // Try honoring the hint first
+       /* Try honoring the hint first */
        uint32_t current = 1, asize = (1 << (64 - assign->length)) - 1;
        if (assign->assigned) {
                list_for_each_entry(c, &iface->ia_assignments, head) {
@@ -459,7 +531,10 @@ 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;
                        }
 
@@ -468,7 +543,7 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
                }
        }
 
-       // Fallback to a variable assignment
+       /* Fallback to a variable assignment */
        current = 1;
        list_for_each_entry(c, &iface->ia_assignments, head) {
                if (c->length == 128 || c->length == 0)
@@ -478,7 +553,10 @@ 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;
                }
 
@@ -489,33 +567,15 @@ static bool assign_pd(struct interface *iface, struct dhcpv6_assignment *assign)
        return false;
 }
 
-
 static bool assign_na(struct interface *iface, struct dhcpv6_assignment *assign)
 {
-       bool match = false;
-       for (size_t i = 0; i < iface->ia_addr_len; ++i) {
-               if (!iface->ia_addr[i].has_class) {
-                       match = true;
-                       continue;
-               } else if (assign->classes_cnt) {
-                       for (size_t j = 0; j < assign->classes_cnt; ++j)
-                               if (assign->classes[j] == iface->ia_addr[i].class)
-                                       match = true;
-               } else if (assign->all_class) {
-                       match = true;
-               }
-       }
-
-       if (!match)
-               return false;
-
-       // Seed RNG with checksum of DUID
+       /* Seed RNG with checksum of DUID */
        uint32_t seed = 0;
        for (size_t i = 0; i < assign->clid_len; ++i)
                seed += assign->clid_data[i];
        srand(seed);
 
-       // Try to assign up to 100x
+       /* Try to assign up to 100x */
        for (size_t i = 0; i < 100; ++i) {
                uint32_t try;
                do try = ((uint32_t)rand()) % 0x0fff; while (try < 0x100);
@@ -529,113 +589,85 @@ static bool assign_na(struct interface *iface, struct dhcpv6_assignment *assign)
                                assign->assigned = try;
                                list_add_tail(&assign->head, &c->head);
                                return true;
-                       } else if (c->assigned == try) {
+                       } else if (c->assigned == try)
                                break;
-                       }
                }
        }
 
        return false;
 }
 
-
-static int prefixcmp(const void *va, const void *vb)
+void dhcpv6_ia_preupdate(struct interface *iface)
 {
-       const struct odhcpd_ipaddr *a = va, *b = vb;
-       uint32_t a_pref = ((a->addr.s6_addr[0] & 0xfe) != 0xfc) ? a->preferred : 1;
-       uint32_t b_pref = ((b->addr.s6_addr[0] & 0xfe) != 0xfc) ? b->preferred : 1;
-       return (a_pref < b_pref) ? 1 : (a_pref > b_pref) ? -1 : 0;
-}
+       if (iface->dhcpv6 != RELAYD_SERVER)
+               return;
 
+       struct dhcpv6_assignment *c, *border = list_last_entry(
+                       &iface->ia_assignments, struct dhcpv6_assignment, head);
 
-static void update(struct interface *iface)
-{
-       struct odhcpd_ipaddr addr[8];
-       memset(addr, 0, sizeof(addr));
-       int len = odhcpd_get_interface_addresses(iface->ifindex, addr, 8);
+       list_for_each_entry(c, &iface->ia_assignments, head)
+               if (c != border && !iface->managed && (c->flags & OAF_BOUND))
+                       apply_lease(iface, c, false);
+}
 
-       if (len < 0)
+void dhcpv6_ia_postupdate(struct interface *iface, time_t now)
+{
+       if (iface->dhcpv6 != RELAYD_SERVER)
                return;
 
-       qsort(addr, len, sizeof(*addr), prefixcmp);
-
-       time_t now = odhcpd_time();
        int minprefix = -1;
-
-       for (int i = 0; i < len; ++i) {
-               if (addr[i].prefix > minprefix)
-                       minprefix = addr[i].prefix;
-
-               addr[i].addr.s6_addr32[3] = 0;
-
-               if (addr[i].preferred < UINT32_MAX - now)
-                       addr[i].preferred += now;
-
-               if (addr[i].valid < UINT32_MAX - now)
-                       addr[i].valid += now;
+       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;
        }
 
-       struct dhcpv6_assignment *border = list_last_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
-       border->assigned = 1 << (64 - minprefix);
+       struct dhcpv6_assignment *border = list_last_entry(
+                       &iface->ia_assignments, struct dhcpv6_assignment, head);
 
-       bool change = len != (int)iface->ia_addr_len;
-       for (int i = 0; !change && i < len; ++i)
-               if (addr[i].addr.s6_addr32[0] != iface->ia_addr[i].addr.s6_addr32[0] ||
-                               addr[i].addr.s6_addr32[1] != iface->ia_addr[i].addr.s6_addr32[1] ||
-                               (addr[i].preferred > 0) != (iface->ia_addr[i].preferred > 0) ||
-                               (addr[i].valid > (uint32_t)now + 7200) !=
-                                               (iface->ia_addr[i].valid > (uint32_t)now + 7200))
-                       change = true;
+       if (minprefix > 32 && minprefix <= 64)
+               border->assigned = 1U << (64 - minprefix);
+       else
+               border->assigned = 0;
 
-       if (change) {
-               struct dhcpv6_assignment *c;
-               list_for_each_entry(c, &iface->ia_assignments, head)
-                       if (c != border)
-                               apply_lease(iface, c, false);
-       }
-
-       memcpy(iface->ia_addr, addr, len * sizeof(*addr));
-       iface->ia_addr_len = len;
+       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)
+                       continue;
 
-       if (change) { // Addresses / prefixes have changed
-               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 || c->valid_until < now || c->managed_size)
-                               continue;
+               if (c->length < 128 && c->assigned >= border->assigned && c != border)
+                       list_move(&c->head, &reassign);
+               else if (c != border && (c->flags & OAF_BOUND))
+                       apply_lease(iface, c, true);
 
-                       if (c->length < 128 && c->assigned >= border->assigned && c != border)
-                               list_move(&c->head, &reassign);
-                       else if (c != border)
-                               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);
-
-                               // 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;
-                       }
+               if (c->accept_reconf && c->reconf_cnt == 0) {
+                       c->reconf_cnt = 1;
+                       c->reconf_sent = now;
+                       send_reconf(iface, 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;
                }
+       }
 
-               while (!list_empty(&reassign)) {
-                       c = list_first_entry(&reassign, struct dhcpv6_assignment, head);
-                       list_del(&c->head);
-                       if (!assign_pd(iface, c)) {
-                               c->assigned = 0;
-                               list_add(&c->head, &iface->ia_assignments);
-                       }
+       while (!list_empty(&reassign)) {
+               c = list_first_entry(&reassign, struct dhcpv6_assignment, head);
+               list_del(&c->head);
+               if (!assign_pd(iface, c)) {
+                       c->assigned = 0;
+                       list_add(&c->head, &iface->ia_assignments);
                }
-
-               dhcpv6_write_statefile();
        }
-}
 
+       dhcpv6_write_statefile();
+}
 
 static void reconf_timer(struct uloop_timeout *event)
 {
@@ -647,12 +679,11 @@ static void reconf_timer(struct uloop_timeout *event)
 
                struct dhcpv6_assignment *a, *n;
                list_for_each_entry_safe(a, n, &iface->ia_assignments, head) {
-                       if (a->valid_until < now) {
+                       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)) {
-                                       list_del(&a->head);
+                                               (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;
@@ -664,7 +695,6 @@ static void reconf_timer(struct uloop_timeout *event)
        uloop_timeout_set(event, 2000);
 }
 
-
 static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                const struct dhcpv6_ia_hdr *ia, struct dhcpv6_assignment *a,
                struct interface *iface, bool request)
@@ -688,48 +718,36 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                datalen += sizeof(stat);
        } else {
                if (a) {
-                       uint32_t pref = 3600;
-                       uint32_t valid = 3600;
+                       uint32_t leasetime;
+                       if (a->leasetime > 0)
+                               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;
-                       for (size_t i = 0; i < addrlen; ++i) {
-                               bool match = true;
-                               if (addrs[i].has_class) {
-                                       match = false;
-                                       if (a->classes_cnt) {
-                                               for (size_t j = 0; j < a->classes_cnt; ++j)
-                                                       if (a->classes[j] == addrs[i].class)
-                                                               match = true;
-                                       } else if (a->all_class) {
-                                               match = true;
-                                       }
-                               }
+                       size_t m = elect_addr(addrs, addrlen);
 
-                               if (!match)
-                                       continue;
-
-                               uint32_t prefix_pref = addrs[i].preferred - now;
-                               uint32_t prefix_valid = addrs[i].valid - now;
+                       for (size_t i = 0; i < addrlen; ++i) {
+                               uint32_t prefix_pref = addrs[i].preferred;
+                               uint32_t prefix_valid = addrs[i].valid;
 
-                               if (addrs[i].prefix > 96 ||
-                                               addrs[i].preferred <= (uint32_t)now)
+                               if (!valid_addr(&addrs[i], now))
                                        continue;
 
-                               if (prefix_pref > 86400)
-                                       prefix_pref = 86400;
+                               if (prefix_pref != UINT32_MAX)
+                                       prefix_pref -= now;
 
-                               if (prefix_valid > 86400)
-                                       prefix_valid = 86400;
-
-#ifdef DHCPV6_OPT_PREFIX_CLASS
-                               struct {
-                                       uint16_t code;
-                                       uint16_t length;
-                                       uint16_t class;
-                               } pclass = {htons(DHCPV6_OPT_PREFIX_CLASS),
-                                       htons(2), htons(iface->ia_addr[i].class)};
-#endif
+                               if (prefix_valid != UINT32_MAX)
+                                       prefix_valid -= now;
 
                                if (a->length < 128) {
                                        struct dhcpv6_ia_prefix p = {
@@ -737,27 +755,19 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                                                .len = htons(sizeof(p) - 4),
                                                .preferred = htonl(prefix_pref),
                                                .valid = htonl(prefix_valid),
-                                               .prefix = (a->managed_size) ? a->managed_size : a->length,
+                                               .prefix = (a->managed_size) ? addrs[i].prefix : a->length,
                                                .addr = addrs[i].addr
                                        };
                                        p.addr.s6_addr32[1] |= htonl(a->assigned);
 
                                        size_t entrlen = sizeof(p) - 4;
 
-#ifdef DHCPV6_OPT_PREFIX_CLASS
-                                       if (iface->ia_addr[i].has_class) {
-                                               entrlen += sizeof(pclass);
-                                               p.len = htons(entrlen);
-                                       }
-#endif
-
-                                       if (datalen + entrlen + 4 > buflen || a->assigned == 0)
+                                       if (datalen + entrlen + 4 > buflen ||
+                                                       (a->assigned == 0 && a->managed_size == 0) ||
+                                                       !valid_prefix_length(a, addrs[i].prefix))
                                                continue;
 
                                        memcpy(buf + datalen, &p, sizeof(p));
-#ifdef DHCPV6_OPT_PREFIX_CLASS
-                                       memcpy(buf + datalen + sizeof(p), &pclass, sizeof(pclass));
-#endif
                                        datalen += entrlen + 4;
                                } else {
                                        struct dhcpv6_ia_addr n = {
@@ -770,24 +780,16 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                                        n.addr.s6_addr32[3] = htonl(a->assigned);
                                        size_t entrlen = sizeof(n) - 4;
 
-#ifdef DHCPV6_OPT_PREFIX_CLASS
-                                       if (iface->ia_addr[i].has_class) {
-                                               entrlen += sizeof(pclass);
-                                               n.len = htons(entrlen);
-                                       }
-#endif
-
-                                       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));
-#ifdef DHCPV6_OPT_PREFIX_CLASS
-                                       memcpy(buf + datalen + sizeof(n), &pclass, sizeof(pclass));
-#endif
                                        datalen += entrlen + 4;
                                }
 
-                               // Calculate T1 / T2 based on non-deprecated addresses
+                               /* Calculate T1 / T2 based on non-deprecated addresses */
                                if (prefix_pref > 0) {
                                        if (prefix_pref < pref)
                                                pref = prefix_pref;
@@ -797,9 +799,12 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                                }
                        }
 
-                       a->valid_until = valid + now;
-                       out.t1 = htonl(pref * 5 / 10);
-                       out.t2 = htonl(pref * 8 / 10);
+                       if (!INFINITE_VALID(a->valid_until))
+                               /* UINT32_MAX is considered as infinite leasetime */
+                               a->valid_until = (valid == UINT32_MAX) ? 0 : valid + now;
+
+                       out.t1 = htonl((pref == UINT32_MAX) ? pref : pref * 5 / 10);
+                       out.t2 = htonl((pref == UINT32_MAX) ? pref : pref * 8 / 10);
 
                        if (!out.t1)
                                out.t1 = htonl(1);
@@ -824,8 +829,7 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                                        size_t addrlen = (a->managed) ? (size_t)a->managed_size : iface->ia_addr_len;
 
                                        for (size_t i = 0; i < addrlen; ++i) {
-                                               if (addrs[i].prefix > 96 ||
-                                                               addrs[i].preferred <= (uint32_t)now)
+                                               if (!valid_addr(&addrs[i], now))
                                                        continue;
 
                                                struct in6_addr addr = addrs[i].addr;
@@ -833,7 +837,7 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
                                                        addr.s6_addr32[1] |= htonl(a->assigned);
 
                                                        if (!memcmp(&p->addr, &addr, sizeof(addr)) &&
-                                                                       p->prefix == a->length)
+                                                                       p->prefix == ((a->managed) ? addrs[i].prefix : a->length))
                                                                found = true;
                                                } else {
                                                        addr.s6_addr32[3] = htonl(a->assigned);
@@ -885,8 +889,96 @@ static size_t append_reply(uint8_t *buf, size_t buflen, uint16_t status,
        return datalen;
 }
 
+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 *type = "UNKNOWN";
+       const char *status = "UNKNOWN";
+
+       if (msgtype == DHCPV6_MSG_RENEW)
+               return;
+
+       switch (msgtype) {
+       case DHCPV6_MSG_SOLICIT:
+               type = "SOLICIT";
+               break;
+       case DHCPV6_MSG_REQUEST:
+               type = "REQUEST";
+               break;
+       case DHCPV6_MSG_CONFIRM:
+               type = "CONFIRM";
+               break;
+       case DHCPV6_MSG_RENEW:
+               type = "RENEW";
+               break;
+       case DHCPV6_MSG_REBIND:
+               type = "REBIND";
+               break;
+       case DHCPV6_MSG_RELEASE:
+               type = "RELEASE";
+               break;
+       case DHCPV6_MSG_DECLINE:
+               type = "DECLINE";
+               break;
+       }
+
+       switch (code) {
+       case DHCPV6_STATUS_OK:
+               status = "ok";
+               break;
+       case DHCPV6_STATUS_NOADDRSAVAIL:
+               status = "no addresses available";
+               break;
+       case DHCPV6_STATUS_NOBINDING:
+               status = "no binding";
+               break;
+       case DHCPV6_STATUS_NOTONLINK:
+               status = "not on-link";
+               break;
+       case DHCPV6_STATUS_NOPREFIXAVAIL:
+               status = "no prefix available";
+               break;
+       }
+
+       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;
+               size_t m = elect_addr(addrs, addrlen);
+               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) {
+                               if (!ADDR_ENTRY_VALID_IA_ADDR(iface, i, m, addrs) ||
+                                               a->assigned == 0)
+                                       continue;
+
+                               addr.s6_addr32[3] = htonl(a->assigned);
+                       }
+                       else {
+                               if (!valid_prefix_length(a, addrs[i].prefix))
+                                       continue;
+
+                               addr.s6_addr32[1] |= htonl(a->assigned);
+                       }
+
+                       inet_ntop(AF_INET6, &addr, addrbuf, sizeof(addrbuf));
+                       lbsize += snprintf(leasebuf + lbsize, sizeof(leasebuf) - lbsize, "%s/%d ", addrbuf, prefix);
+               }
+       }
+
+       syslog(LOG_WARNING, "DHCPV6 %s %s from %s on %s: %s %s", type, (is_pd) ? "IA_PD" : "IA_NA",
+                       duidbuf, iface->ifname, status, leasebuf);
+}
 
-size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
+ssize_t dhcpv6_handle_ia(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();
@@ -894,13 +986,14 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
        const struct dhcpv6_client_header *hdr = data;
        uint8_t *start = (uint8_t*)&hdr[1], *odata;
        uint16_t otype, olen;
-
-       // Find and parse client-id and hostname
+       /* Find and parse client-id and hostname */
        bool accept_reconf = false;
        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 class_oro = false;
+       bool notonlink = false;
+       char duidbuf[261];
+
        dhcpv6_for_each_option(start, end, otype, olen, odata) {
                if (otype == DHCPV6_OPT_CLIENTID) {
                        clid_data = odata;
@@ -910,6 +1003,9 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                                memcpy(mac, &odata[8], sizeof(mac));
                        else if (olen == 10 && odata[0] == 0 && odata[1] == 3)
                                memcpy(mac, &odata[4], sizeof(mac));
+
+                       if (olen <= 130)
+                               odhcpd_hexlify(duidbuf, odata, olen);
                } else if (otype == DHCPV6_OPT_FQDN && olen >= 2 && olen <= 255) {
                        uint8_t fqdn_buf[256];
                        memcpy(fqdn_buf, odata, olen);
@@ -917,30 +1013,18 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 
                        if (dn_expand(&fqdn_buf[1], &fqdn_buf[olen], &fqdn_buf[1], hostname, sizeof(hostname)) > 0)
                                hostname_len = strcspn(hostname, ".");
-               } else if (otype == DHCPV6_OPT_ORO) {
-#ifdef DHCPV6_OPT_PREFIX_CLASS
-                       for (size_t i = 0; i + 1 < olen; i += 2) {
-                               if (odata[i] == (DHCPV6_OPT_PREFIX_CLASS >> 8) &&
-                                               odata[i + 1] == (DHCPV6_OPT_PREFIX_CLASS & 0xff))
-                                       class_oro = true;
-                       }
-#endif
-               } else if (otype == DHCPV6_OPT_RECONF_ACCEPT) {
+               } else if (otype == DHCPV6_OPT_RECONF_ACCEPT)
                        accept_reconf = true;
-               }
        }
 
        if (!clid_data || !clid_len || clid_len > 130)
                goto out;
 
-       update(iface);
-       bool update_state = false;
-       bool managed_pd_out = false;
-
        struct dhcpv6_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);
+               bool ia_addr_present = false;
                if (!is_pd && !is_na)
                        continue;
 
@@ -949,11 +1033,7 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                uint8_t reqlen = (is_pd) ? 62 : 128;
                uint32_t reqhint = 0;
 
-               const uint8_t classes_max = 32;
-               uint8_t classes_cnt = 0;
-               uint16_t classes[classes_max];
-
-               // Parse request hint for IA-PD
+               /* Parse request hint for IA-PD */
                if (is_pd) {
                        uint8_t *sdata;
                        uint16_t stype, slen;
@@ -968,20 +1048,6 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                                        if (reqlen > 32 && reqlen <= 64)
                                                reqhint &= (1U << (64 - reqlen)) - 1;
                                }
-
-#ifdef DHCPV6_OPT_PREFIX_CLASS
-                               uint8_t *xdata;
-                               uint16_t xtype, xlen;
-                               dhcpv6_for_each_option(&p[1], sdata + slen, xtype, xlen, xdata) {
-                                       if (xtype != DHCPV6_OPT_PREFIX_CLASS || xlen != 2)
-                                               continue;
-
-                                       if (classes_cnt >= classes_max)
-                                               continue;
-
-                                       classes[classes_cnt++] = (uint16_t)xdata[0] << 8 | (uint16_t)xdata[1];
-                               }
-#endif
                        }
 
                        if (reqlen > 64)
@@ -993,60 +1059,44 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                                if (stype != DHCPV6_OPT_IA_ADDR || slen < sizeof(struct dhcpv6_ia_addr) - 4)
                                        continue;
 
-#ifdef DHCPV6_OPT_PREFIX_CLASS
-                               uint8_t *xdata;
-                               uint16_t xtype, xlen;
-                               struct dhcpv6_ia_addr *p = (struct dhcpv6_ia_addr*)&sdata[-4];
-                               dhcpv6_for_each_option(&p[1], sdata + slen, xtype, xlen, xdata) {
-                                       if (xtype != DHCPV6_OPT_PREFIX_CLASS || xlen != 2)
-                                               continue;
-
-                                       if (classes_cnt >= classes_max)
-                                               continue;
-
-                                       classes[classes_cnt++] = (uint16_t)xdata[0] << 8 | (uint16_t)xdata[1];
-                               }
-#endif
+                               ia_addr_present = true;
                        }
                }
 
-               // Find assignment
+               /* Find assignment */
                struct dhcpv6_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 || c->valid_until < now) &&
+                                               && !memcmp(c->mac, mac, sizeof(mac)))) &&
+                                       (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;
-                               a->all_class = class_oro;
-                               a->classes_cnt = classes_cnt;
-                               a->classes = realloc(a->classes, classes_cnt * sizeof(uint16_t));
-                               if (a->classes)
-                                       memcpy(a->classes, classes, classes_cnt * sizeof(uint16_t));
                                break;
                        }
                }
 
-               // Generic message handling
+               /* Generic message handling */
                uint16_t status = DHCPV6_STATUS_OK;
-               if (a && a->managed_size < 0) {
-                       managed_pd_out = true;
-                       status = DHCPV6_STATUS_NOTONLINK;
-                       ia_response_len = append_reply(buf, buflen, status, ia, NULL, iface, true);
-               } else if (hdr->msg_type == DHCPV6_MSG_SOLICIT || hdr->msg_type == DHCPV6_MSG_REQUEST) {
+               if (a && a->managed_size < 0)
+                       return -1;
+
+               if (hdr->msg_type == DHCPV6_MSG_SOLICIT || hdr->msg_type == DHCPV6_MSG_REQUEST) {
                        bool assigned = !!a;
 
-                       if (!a && !iface->no_dynamic_dhcp) { // Create new binding
+                       if (!a && !iface->no_dynamic_dhcp) {
+                               /* Create new binding */
                                a = calloc(1, sizeof(*a) + clid_len);
                                if (a) {
                                        a->clid_len = clid_len;
@@ -1054,13 +1104,9 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                                        a->length = reqlen;
                                        a->peer = *addr;
                                        a->assigned = reqhint;
-                                       a->all_class = class_oro;
-                                       a->classes_cnt = classes_cnt;
-                                       if (classes_cnt) {
-                                               a->classes = malloc(classes_cnt * sizeof(uint16_t));
-                                               if (a->classes)
-                                                       memcpy(a->classes, classes, classes_cnt * sizeof(uint16_t));
-                                       }
+                                       /* Set valid time to current time indicating  */
+                                       /* assignment is not having infinite lifetime */
+                                       a->valid_until = now;
 
                                        if (first)
                                                memcpy(a->key, first->key, sizeof(a->key));
@@ -1070,18 +1116,19 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 
                                        if (is_pd)
                                                while (!(assigned = assign_pd(iface, a)) &&
-                                                               ++a->length <= 64 && !a->managed_size);
+                                                               !a->managed_size && ++a->length <= 64);
                                        else
                                                assigned = assign_na(iface, a);
 
                                        if (a->managed_size && !assigned)
-                                               managed_pd_out = true;
+                                               return -1;
                                }
                        }
 
-                       if (!assigned || iface->ia_addr_len == 0) { // Set error status
+                       if (!assigned || iface->ia_addr_len == 0)
+                               /* Set error status */
                                status = (is_pd) ? DHCPV6_STATUS_NOPREFIXAVAIL : DHCPV6_STATUS_NOADDRSAVAIL;
-                       } else if (assigned && !first) { //
+                       else if (assigned && !first) {
                                size_t handshake_len = 4;
                                buf[0] = 0;
                                buf[1] = DHCPV6_OPT_RECONF_ACCEPT;
@@ -1111,9 +1158,12 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
 
                        ia_response_len = append_reply(buf, buflen, status, ia, a, iface, true);
 
-                       // Was only a solicitation: mark binding for removal
+                       /* Was only a solicitation: mark binding for removal */
                        if (assigned && hdr->msg_type == DHCPV6_MSG_SOLICIT) {
-                               a->valid_until = now + 15;
+                               a->flags &= ~OAF_BOUND;
+
+                               if (!(a->flags & OAF_STATIC))
+                                       a->valid_until = now;
                        } else if (assigned && hdr->msg_type == DHCPV6_MSG_REQUEST) {
                                if (hostname_len > 0) {
                                        a->hostname = realloc(a->hostname, hostname_len + 1);
@@ -1123,10 +1173,12 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                                        }
                                }
                                a->accept_reconf = accept_reconf;
+                               a->flags |= OAF_BOUND;
                                apply_lease(iface, a, true);
-                               update_state = true;
-                       } else if (!assigned && a) { // Cleanup failed assignment
+                       } 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 ||
@@ -1138,48 +1190,51 @@ size_t dhcpv6_handle_ia(uint8_t *buf, size_t buflen, struct interface *iface,
                        } 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);
-                               if (a)
+                               if (a) {
+                                       a->flags |= OAF_BOUND;
                                        apply_lease(iface, a, true);
+                               }
                        } else if (hdr->msg_type == DHCPV6_MSG_RELEASE) {
-                               a->valid_until = 0;
-                               apply_lease(iface, a, false);
-                               update_state = true;
+                               if (!(a->flags & OAF_STATIC))
+                                       a->valid_until = now - 1;
+
+                               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->clid_len = 0;
-                               a->valid_until = now + 3600; // Block address for 1h
-                               update_state = true;
+                               a->flags &= ~OAF_BOUND;
+
+                               if (!(a->flags & OAF_STATIC)) {
+                                       a->clid_len = 0;
+                                       a->valid_until = now + 3600; /* Block address for 1h */
+                               }
                        }
-               } else if (hdr->msg_type == DHCPV6_MSG_CONFIRM) {
-                       // Always send NOTONLINK for CONFIRM so that clients restart connection
+               } 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;
                }
 
                buf += ia_response_len;
                buflen -= ia_response_len;
                response_len += ia_response_len;
+               dhcpv6_log(hdr->msg_type, iface, now, duidbuf, is_pd, a, status);
        }
 
-       if (hdr->msg_type == DHCPV6_MSG_RELEASE && response_len + 6 < buflen) {
-               buf[0] = 0;
-               buf[1] = DHCPV6_OPT_STATUS;
-               buf[2] = 0;
-               buf[3] = 2;
-               buf[4] = 0;
-               buf[5] = DHCPV6_STATUS_OK;
-               response_len += 6;
-       } else if (managed_pd_out && response_len + 6 < buflen) {
+       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] = DHCPV6_STATUS_NOADDRSAVAIL;
+               buf[5] = (notonlink) ? DHCPV6_STATUS_NOTONLINK : DHCPV6_STATUS_OK;
                response_len += 6;
        }
 
-       if (update_state)
-               dhcpv6_write_statefile();
+       dhcpv6_write_statefile();
 
 out:
        return response_len;