IPv6: Set loopback-policy for output traffic
[project/netifd.git] / interface-ip.c
index ea4c3dd..e265563 100644 (file)
@@ -1,6 +1,7 @@
 /*
  * netifd - network interface daemon
  * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
+ * Copyright (C) 2012 Steven Barth <steven@midlink.org>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2
@@ -33,6 +34,8 @@ enum {
        ROUTE_GATEWAY,
        ROUTE_METRIC,
        ROUTE_MTU,
+       ROUTE_VALID,
+       ROUTE_TABLE,
        __ROUTE_MAX
 };
 
@@ -43,6 +46,8 @@ static const struct blobmsg_policy route_attr[__ROUTE_MAX] = {
        [ROUTE_GATEWAY] = { .name = "gateway", .type = BLOBMSG_TYPE_STRING },
        [ROUTE_METRIC] = { .name = "metric", .type = BLOBMSG_TYPE_INT32 },
        [ROUTE_MTU] = { .name = "mtu", .type = BLOBMSG_TYPE_INT32 },
+       [ROUTE_TABLE] = { .name = "table", .type = BLOBMSG_TYPE_STRING },
+       [ROUTE_VALID] = { .name = "valid", .type = BLOBMSG_TYPE_INT32 },
 };
 
 const struct config_param_list route_attr_list = {
@@ -53,6 +58,7 @@ const struct config_param_list route_attr_list = {
 
 struct list_head prefixes = LIST_HEAD_INIT(prefixes);
 static struct device_prefix *ula_prefix = NULL;
+static struct uloop_timeout valid_until_timeout;
 
 
 static void
@@ -84,6 +90,31 @@ match_if_addr(union if_addr *a1, union if_addr *a2, int mask)
        return !memcmp(p1, p2, sizeof(*p1));
 }
 
+static int set_ipv6_source_policy(bool add, const union if_addr *addr, uint8_t mask, int ifindex)
+{
+       struct iprule rule = {
+               .flags = IPRULE_INET6 | IPRULE_SRC | IPRULE_LOOKUP | IPRULE_PRIORITY,
+               .priority = 65535,
+               .lookup = interface_ip_resolve_v6_rtable(ifindex),
+               .src_addr = *addr,
+               .src_mask = mask,
+       };
+
+       return (add) ? system_add_iprule(&rule) : system_del_iprule(&rule);
+}
+
+static int set_ipv6_lo_policy(bool add, int ifindex)
+{
+       struct iprule rule = {
+               .flags = IPRULE_INET6 | IPRULE_IN | IPRULE_LOOKUP | IPRULE_PRIORITY,
+               .priority = 65535,
+               .lookup = interface_ip_resolve_v6_rtable(ifindex),
+               .in_dev = "lo"
+       };
+
+       return (add) ? system_add_iprule(&rule) : system_del_iprule(&rule);
+}
+
 static bool
 __find_ip_addr_target(struct interface_ip_settings *ip, union if_addr *a, bool v6)
 {
@@ -96,7 +127,13 @@ __find_ip_addr_target(struct interface_ip_settings *ip, union if_addr *a, bool v
                if (v6 != ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET6))
                        continue;
 
-               if (!match_if_addr(&addr->addr, a, addr->mask))
+               // Handle offlink addresses correctly
+               unsigned int mask = addr->mask;
+               if ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET6 &&
+                               (addr->flags & DEVADDR_OFFLINK))
+                       mask = 128;
+
+               if (!match_if_addr(&addr->addr, a, mask))
                        continue;
 
                return true;
@@ -121,6 +158,9 @@ __find_ip_route_target(struct interface_ip_settings *ip, union if_addr *a,
                if (!match_if_addr(&route->addr, a, route->mask))
                        continue;
 
+               if (route->flags & DEVROUTE_TABLE)
+                       continue;
+
                if (!*res || route->mask < (*res)->mask)
                        *res = route;
        }
@@ -142,9 +182,8 @@ interface_ip_find_route_target(struct interface *iface, union if_addr *a,
 }
 
 struct interface *
-interface_ip_add_target_route(union if_addr *addr, bool v6)
+interface_ip_add_target_route(union if_addr *addr, bool v6, struct interface *iface)
 {
-       struct interface *iface;
        struct device_route *route, *r_next = NULL;
        bool defaultroute_target = false;
        int addrsize = v6 ? sizeof(addr->in6) : sizeof(addr->in);
@@ -160,7 +199,7 @@ interface_ip_add_target_route(union if_addr *addr, bool v6)
        else
                memcpy(&route->addr, addr, addrsize);
 
-       vlist_for_each_element(&interfaces, iface, node) {
+       if (iface) {
                /* look for locally addressable target first */
                if (interface_ip_find_addr_target(iface, addr, v6))
                        goto done;
@@ -168,6 +207,16 @@ interface_ip_add_target_route(union if_addr *addr, bool v6)
                /* do not stop at the first route, let the lookup compare
                 * masks to find the best match */
                interface_ip_find_route_target(iface, addr, v6, &r_next);
+       } else {
+               vlist_for_each_element(&interfaces, iface, node) {
+                       /* look for locally addressable target first */
+                       if (interface_ip_find_addr_target(iface, addr, v6))
+                               goto done;
+
+                       /* do not stop at the first route, let the lookup compare
+                        * masks to find the best match */
+                       interface_ip_find_route_target(iface, addr, v6, &r_next);
+               }
        }
 
        if (!r_next) {
@@ -179,13 +228,14 @@ interface_ip_add_target_route(union if_addr *addr, bool v6)
        memcpy(&route->nexthop, &r_next->nexthop, sizeof(route->nexthop));
        route->mtu = r_next->mtu;
        route->metric = r_next->metric;
+       route->table = r_next->table;
 
 done:
        route->iface = iface;
        if (defaultroute_target)
                free(route);
        else
-               vlist_add(&iface->host_routes, &route->node, &route->flags);
+               vlist_add(&iface->host_routes, &route->node, route);
        return iface;
 }
 
@@ -196,6 +246,7 @@ interface_ip_add_route(struct interface *iface, struct blob_attr *attr, bool v6)
        struct blob_attr *tb[__ROUTE_MAX], *cur;
        struct device_route *route;
        int af = v6 ? AF_INET6 : AF_INET;
+       bool is_v6_proto_route = v6 && iface;
 
        blobmsg_parse(route_attr, __ROUTE_MAX, tb, blobmsg_data(attr), blobmsg_data_len(attr));
 
@@ -248,7 +299,26 @@ interface_ip_add_route(struct interface *iface, struct blob_attr *attr, bool v6)
                route->flags |= DEVROUTE_MTU;
        }
 
-       vlist_add(&ip->route, &route->node, &route->flags);
+       // Use source-based routing
+       if (is_v6_proto_route) {
+               route->table = interface_ip_resolve_v6_rtable(iface->l3_dev.dev->ifindex);
+               route->flags |= DEVROUTE_SRCTABLE;
+       }
+
+       if ((cur = tb[ROUTE_TABLE]) != NULL) {
+               if (!system_resolve_rt_table(blobmsg_data(cur), &route->table)) {
+                       DPRINTF("Failed to resolve routing table: %s\n", (char *) blobmsg_data(cur));
+                       goto error;
+               }
+
+               if (route->table)
+                       route->flags |= DEVROUTE_TABLE;
+       }
+
+       if ((cur = tb[ROUTE_VALID]) != NULL)
+               route->valid_until = system_get_rtime() + blobmsg_get_u32(cur);
+
+       vlist_add(&ip->route, &route->node, route);
        return;
 
 error:
@@ -265,8 +335,18 @@ addr_cmp(const void *k1, const void *k2, void *ptr)
 static int
 route_cmp(const void *k1, const void *k2, void *ptr)
 {
-       return memcmp(k1, k2, sizeof(struct device_route) -
-                     offsetof(struct device_route, flags));
+       const struct device_route *r1 = k1, *r2 = k2;
+
+       if (r1->mask != r2->mask)
+               return r2->mask - r1->mask;
+
+       if (r1->metric != r2->metric)
+               return r1->metric - r2->metric;
+
+       if (r1->flags != r2->flags)
+               return r2->flags - r1->flags;
+
+       return memcmp(&r1->addr, &r2->addr, sizeof(r1->addr));
 }
 
 static int
@@ -293,11 +373,14 @@ interface_handle_subnet_route(struct interface *iface, struct device_addr *addr,
                route.flags |= DEVADDR_KERNEL;
                system_del_route(dev, &route);
 
-               route.flags &= ~DEVADDR_KERNEL;
-               route.metric = iface->metric;
-               system_add_route(dev, &route);
+               if (!(addr->flags & DEVADDR_OFFLINK)) {
+                       route.flags &= ~DEVADDR_KERNEL;
+                       route.metric = iface->metric;
+                       system_add_route(dev, &route);
+               }
        } else {
-               system_del_route(dev, &route);
+               if (!(addr->flags & DEVADDR_OFFLINK))
+                       system_del_route(dev, &route);
        }
 }
 
@@ -336,7 +419,9 @@ interface_update_proto_addr(struct vlist_tree *tree,
        if (a_new && a_old) {
                keep = true;
 
-               if (a_old->flags != a_new->flags)
+               if (a_old->flags != a_new->flags ||
+                               a_old->valid_until != a_new->valid_until ||
+                               a_old->preferred_until != a_new->preferred_until)
                        keep = false;
 
                if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
@@ -347,6 +432,10 @@ interface_update_proto_addr(struct vlist_tree *tree,
        if (node_old) {
                if (!(a_old->flags & DEVADDR_EXTERNAL) && a_old->enabled && !keep) {
                        interface_handle_subnet_route(iface, a_old, false);
+
+                       if ((a_old->flags & DEVADDR_FAMILY) == DEVADDR_INET6)
+                               set_ipv6_source_policy(false, &a_old->addr, a_old->mask, dev->ifindex);
+
                        system_del_address(dev, a_old);
                }
                free(a_old);
@@ -356,7 +445,11 @@ interface_update_proto_addr(struct vlist_tree *tree,
                a_new->enabled = true;
                if (!(a_new->flags & DEVADDR_EXTERNAL) && !keep) {
                        system_add_address(dev, a_new);
-                       if (iface->metric)
+
+                       if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET6)
+                               set_ipv6_source_policy(true, &a_new->addr, a_new->mask, dev->ifindex);
+
+                       if ((a_new->flags & DEVADDR_OFFLINK) || iface->metric)
                                interface_handle_subnet_route(iface, a_new, true);
                }
        }
@@ -438,10 +531,45 @@ interface_update_host_route(struct vlist_tree *tree,
 
 
 static void
-interface_set_prefix_address(struct interface *iface, bool add,
-               struct device_prefix_assignment *assignment)
+interface_set_prefix_address(struct device_prefix_assignment *assignment,
+               const struct device_prefix *prefix, struct interface *iface, bool add);
+
+static void interface_trigger_ula_prefix(struct interface *iface,
+               const struct device_prefix *prefix, bool enable)
 {
-       struct interface *uplink = assignment->prefix->iface;
+       if (prefix == ula_prefix || (prefix->addr.s6_addr[0] & 0xfe) != 0xfc)
+               return;
+
+       bool external_ula = false;
+       struct device_prefix_assignment *ula_assign = NULL;
+       struct device_prefix *c;
+       list_for_each_entry(c, &prefixes, head) {
+               if (c != ula_prefix && (c->addr.s6_addr[0] & 0xfe) != 0xfc)
+                       continue;
+
+               struct device_prefix_assignment *a;
+               list_for_each_entry(a, &c->assignments, head) {
+                       if (!strcmp(a->name, iface->name)) {
+                               if (c == ula_prefix)
+                                       ula_assign = a;
+                               else if (a->enabled)
+                                       external_ula = true;
+                       }
+               }
+
+       }
+
+       // Remove ULA assignment if there is an externally managed ULA and vice versa
+       if (ula_assign && ((enable && !external_ula) || (!enable && external_ula)))
+               interface_set_prefix_address(ula_assign, ula_prefix, iface, enable);
+}
+
+
+static void
+interface_set_prefix_address(struct device_prefix_assignment *assignment,
+               const struct device_prefix *prefix, struct interface *iface, bool add)
+{
+       const struct interface *uplink = prefix->iface;
        if (!iface->l3_dev.dev)
                return;
 
@@ -449,108 +577,156 @@ interface_set_prefix_address(struct interface *iface, bool add,
 
        struct device_addr addr;
        memset(&addr, 0, sizeof(addr));
-       addr.addr.in6 = assignment->addr;
+       addr.addr.in6 = prefix->addr;
+       addr.addr.in6.s6_addr32[1] |= htonl(assignment->assigned);
+       addr.addr.in6.s6_addr[15] += 1;
        addr.mask = assignment->length;
        addr.flags = DEVADDR_INET6;
-       addr.preferred_until = assignment->prefix->preferred_until;
-       addr.valid_until = assignment->prefix->valid_until;
-
-       if (!add) {
-               if (assignment->enabled)
-                       system_del_address(l3_downlink, &addr);
-       } else {
+       addr.preferred_until = prefix->preferred_until;
+       addr.valid_until = prefix->valid_until;
+
+       if (!add && assignment->enabled) {
+               time_t now = system_get_rtime();
+               addr.preferred_until = now;
+               if (!addr.valid_until || addr.valid_until - now > 7200)
+                       addr.valid_until = now + 7200;
                system_add_address(l3_downlink, &addr);
+               assignment->enabled = false;
 
+               interface_trigger_ula_prefix(iface, prefix, true);
+       } else if (add && (iface->state == IFS_UP || iface->state == IFS_SETUP)) {
+               system_add_address(l3_downlink, &addr);
                if (uplink && uplink->l3_dev.dev) {
                        int mtu = system_update_ipv6_mtu(
                                        uplink->l3_dev.dev, 0);
                        if (mtu > 0)
                                system_update_ipv6_mtu(l3_downlink, mtu);
                }
+               assignment->enabled = true;
+
+               interface_trigger_ula_prefix(iface, prefix, false);
        }
-       assignment->enabled = add;
 }
 
-
-static void
-interface_update_prefix_assignments(struct vlist_tree *tree,
-                            struct vlist_node *node_new,
-                            struct vlist_node *node_old)
+static bool interface_prefix_assign(struct list_head *list,
+               struct device_prefix_assignment *assign)
 {
-       struct device_prefix_assignment *old, *new;
-       old = container_of(node_old, struct device_prefix_assignment, node);
-       new = container_of(node_new, struct device_prefix_assignment, node);
+       int32_t current = 0, asize = (1 << (64 - assign->length)) - 1;
+       struct device_prefix_assignment *c;
+       list_for_each_entry(c, list, head) {
+               if (assign->assigned != -1) {
+                       if (assign->assigned > current && assign->assigned + asize < c->assigned) {
+                               list_add_tail(&assign->head, &c->head);
+                               return true;
+                       }
+               } else if (assign->assigned == -1) {
+                       current = (current + asize) & (~asize);
+                       if (current + asize < c->assigned) {
+                               assign->assigned = current;
+                               list_add_tail(&assign->head, &c->head);
+                               return true;
+                       }
+               }
+               current = (c->assigned + (1 << (64 - c->length)));
+       }
+       return false;
+}
 
-       // Assignments persist across interface reloads etc.
-       // so use indirection to avoid dangling pointers
-       struct interface *iface = vlist_find(&interfaces,
-                       (node_new) ? new->name : old->name, iface, node);
+static void interface_update_prefix_assignments(struct device_prefix *prefix, bool setup)
+{
+       struct device_prefix_assignment *c;
+       struct interface *iface;
 
-       if (node_old && node_new) {
-               new->addr = old->addr;
-               new->length = old->length;
-       } else if (node_old) {
-               if (iface)
-                       interface_set_prefix_address(iface, false, old);
-               free(old);
-       } else if (node_new) {
-               struct device_prefix *prefix = new->prefix;
-               uint64_t want = 1ULL << (64 - new->length);
-               prefix->avail &= ~(want - 1);
-               prefix->avail -= want;
+       // Delete all assignments
+       while (!list_empty(&prefix->assignments)) {
+               c = list_first_entry(&prefix->assignments,
+                               struct device_prefix_assignment, head);
+               if ((iface = vlist_find(&interfaces, c->name, iface, node)))
+                       interface_set_prefix_address(c, prefix, iface, false);
+               list_del(&c->head);
+               free(c);
+       }
 
-               // Invert assignment
-               uint64_t assigned = ~prefix->avail;
-               assigned &= (1ULL << (64 - prefix->length)) - 1;
-               assigned &= ~(want - 1);
+       if (!setup)
+               return;
 
-               // Assignment
-               new->addr = prefix->addr;
-               new->addr.s6_addr32[0] |=
-                               htonl(assigned >> 32);
-               new->addr.s6_addr32[1] |=
-                               htonl(assigned & 0xffffffffU);
-               new->addr.s6_addr[15] += 1;
+       // End-of-assignment sentinel
+       c = malloc(sizeof(*c) + 1);
+       c->assigned = 1 << (64 - prefix->length);
+       c->length = 64;
+       c->name[0] = 0;
+       list_add(&c->head, &prefix->assignments);
+
+       // Excluded prefix
+       if (prefix->excl_length > 0) {
+               const char name[] = "!excluded";
+               c = malloc(sizeof(*c) + sizeof(name));
+               c->assigned = ntohl(prefix->excl_addr.s6_addr32[1]) &
+                               ((1 << (64 - prefix->length)) - 1);
+               c->length = prefix->excl_length;
+               memcpy(c->name, name, sizeof(name));
+               list_add(&c->head, &prefix->assignments);
        }
 
-       if (node_new && (iface->state == IFS_UP || iface->state == IFS_SETUP))
-               interface_set_prefix_address(iface, true, new);
-}
+       struct list_head assign_later = LIST_HEAD_INIT(assign_later);
+       vlist_for_each_element(&interfaces, iface, node) {
+               if (iface->config_ip.assignment_length < 48 ||
+                               iface->config_ip.assignment_length > 64)
+                       continue;
 
+               size_t namelen = strlen(iface->name) + 1;
+               c = malloc(sizeof(*c) + namelen);
+               c->length = iface->config_ip.assignment_length;
+               c->assigned = iface->config_ip.assignment_hint;
+               c->enabled = false;
+               memcpy(c->name, iface->name, namelen);
+
+               // First process all custom assignments, put all others in later-list
+               if (c->assigned == -1 || !interface_prefix_assign(&prefix->assignments, c)) {
+                       if (c->assigned != -1) {
+                               c->assigned = -1;
+                               netifd_log_message(L_WARNING, "Failed to assign requested subprefix "
+                                               "of size %hhu for %s, trying other\n", c->length, c->name);
+                       }
+                       list_add_tail(&c->head, &assign_later);
+               }
+       }
 
-void
-interface_ip_set_prefix_assignment(struct device_prefix *prefix,
-               struct interface *iface, uint8_t length)
-{
-       struct device_prefix_assignment *assignment;
+       // Then try to assign all other + failed custom assignments
+       while (!list_empty(&assign_later)) {
+               c = list_first_entry(&assign_later, struct device_prefix_assignment, head);
+               list_del(&c->head);
 
-       if (!length || length > 64) {
-               assignment = vlist_find(prefix->assignments, iface->name, assignment, node);
-               if (assignment)
-                       interface_set_prefix_address(iface, false, assignment);
-       } else {
-               uint64_t want = 1ULL << (64 - length);
-               char *name;
+               bool assigned = false;
+               do {
+                       assigned = interface_prefix_assign(&prefix->assignments, c);
+               } while (!assigned && ++c->length <= 64);
 
-               if (prefix->avail < want && prefix->avail > 0) {
-                       do {
-                               want = 1ULL << (64 - ++length);
-                       } while (want > prefix->avail);
+               if (!assigned) {
+                       netifd_log_message(L_WARNING, "Failed to assign subprefix "
+                                       "of size %hhu for %s\n", c->length, c->name);
+                       free(c);
                }
+       }
 
-               if (prefix->avail < want)
-                       return;
+       list_for_each_entry(c, &prefix->assignments, head)
+               if ((iface = vlist_find(&interfaces, c->name, iface, node)))
+                       interface_set_prefix_address(c, prefix, iface, true);
+}
 
-               assignment = calloc_a(sizeof(*assignment),
-                       &name, strlen(iface->name) + 1);
-               assignment->prefix = prefix;
-               assignment->length = length;
-               assignment->name = strcpy(name, iface->name);
 
-               vlist_add(prefix->assignments, &assignment->node, assignment->name);
+void interface_refresh_assignments(bool hint)
+{
+       static bool refresh = false;
+       if (!hint && refresh) {
+               struct device_prefix *p;
+               list_for_each_entry(p, &prefixes, head)
+                       interface_update_prefix_assignments(p, true);
        }
+       refresh = hint;
 }
 
+
 static void
 interface_update_prefix(struct vlist_tree *tree,
                             struct vlist_node *node_new,
@@ -567,55 +743,50 @@ interface_update_prefix(struct vlist_tree *tree,
        route.mask = (node_new) ? prefix_new->length : prefix_old->length;
        route.addr.in6 = (node_new) ? prefix_new->addr : prefix_old->addr;
 
+
+       struct device_prefix_assignment *c;
+       struct interface *iface;
+
        if (node_old && node_new) {
-               prefix_new->avail = prefix_old->avail;
-               prefix_new->assignments = prefix_old->assignments;
-               prefix_old->assignments = NULL;
-
-               // Update all assignments
-               struct device_prefix_assignment *assignment;
-               struct vlist_tree *assignments = prefix_new->assignments;
-               vlist_for_each_element(assignments, assignment, node) {
-                       assignment->prefix = prefix_new;
-                       assignments->update(assignments,
-                                       &assignment->node, &assignment->node);
-               }
+               // Move assignments and refresh addresses to update valid times
+               list_splice(&prefix_old->assignments, &prefix_new->assignments);
+
+               list_for_each_entry(c, &prefix_new->assignments, head)
+                       if ((iface = vlist_find(&interfaces, c->name, iface, node)))
+                               interface_set_prefix_address(c, prefix_new, iface, true);
        } else if (node_new) {
-               prefix_new->avail = 1ULL << (64 - prefix_new->length);
-               prefix_new->assignments = calloc(1, sizeof(*prefix_new->assignments));
-               vlist_init(prefix_new->assignments, avl_strcmp,
-                               interface_update_prefix_assignments);
-
-               // Create initial assignments for interfaces
-               struct interface *iface;
-               vlist_for_each_element(&interfaces, iface, node)
-                       interface_ip_set_prefix_assignment(prefix_new, iface,
-                                       iface->proto_ip.assignment_length);
-
-               // Set null-route to avoid routing loops
+               // Set null-route to avoid routing loops and set routing policy
                system_add_route(NULL, &route);
-       }
+               if (prefix_new->iface)
+                       set_ipv6_source_policy(true, &route.addr, route.mask,
+                                       prefix_new->iface->l3_dev.dev->ifindex);
+
+
+               interface_update_prefix_assignments(prefix_new, true);
+       } else if (node_old) {
+               interface_update_prefix_assignments(prefix_old, false);
 
-       if (node_old) {
                // Remove null-route
+               if (prefix_old->iface)
+                       set_ipv6_source_policy(false, &route.addr, route.mask,
+                                       prefix_old->iface->l3_dev.dev->ifindex);
                system_del_route(NULL, &route);
+       }
 
+       if (node_old) {
                list_del(&prefix_old->head);
-
-               if (prefix_old->assignments) {
-                       vlist_flush_all(prefix_old->assignments);
-                       free(prefix_old->assignments);
-               }
                free(prefix_old);
        }
 
        if (node_new)
                list_add(&prefix_new->head, &prefixes);
+
 }
 
-void
+struct device_prefix*
 interface_ip_add_device_prefix(struct interface *iface, struct in6_addr *addr,
-               uint8_t length, time_t valid_until, time_t preferred_until)
+               uint8_t length, time_t valid_until, time_t preferred_until,
+               struct in6_addr *excl_addr, uint8_t excl_length)
 {
        struct device_prefix *prefix = calloc(1, sizeof(*prefix));
        prefix->length = length;
@@ -623,11 +794,19 @@ interface_ip_add_device_prefix(struct interface *iface, struct in6_addr *addr,
        prefix->preferred_until = preferred_until;
        prefix->valid_until = valid_until;
        prefix->iface = iface;
+       INIT_LIST_HEAD(&prefix->assignments);
+
+       if (excl_addr) {
+               prefix->excl_addr = *excl_addr;
+               prefix->excl_length = excl_length;
+       }
 
        if (iface)
                vlist_add(&iface->proto_ip.prefix, &prefix->node, &prefix->addr);
        else
                interface_update_prefix(NULL, &prefix->node, NULL);
+
+       return prefix;
 }
 
 void
@@ -652,13 +831,19 @@ interface_ip_set_ula_prefix(const char *prefix)
        if (!prefixlen || (length = atoi(prefixlen)) < 1 || length > 64)
                return;
 
-       if (ula_prefix && (!IN6_ARE_ADDR_EQUAL(&addr, &ula_prefix->addr) ||
-                       ula_prefix->length != length)) {
-               interface_update_prefix(NULL, NULL, &ula_prefix->node);
-               ula_prefix = NULL;
+       if (!ula_prefix || !IN6_ARE_ADDR_EQUAL(&addr, &ula_prefix->addr) ||
+                       ula_prefix->length != length) {
+               if (ula_prefix)
+                       interface_update_prefix(NULL, NULL, &ula_prefix->node);
+
+               ula_prefix = interface_ip_add_device_prefix(NULL, &addr, length,
+                               0, 0, NULL, 0);
        }
+}
 
-       interface_ip_add_device_prefix(NULL, &addr, length, 0, 0);
+int interface_ip_resolve_v6_rtable(int ifindex)
+{
+       return ifindex + 1000;
 }
 
 void
@@ -742,7 +927,7 @@ write_resolv_conf_entries(FILE *f, struct interface_ip_settings *ip)
        struct dns_server *s;
        struct dns_search_domain *d;
        const char *str;
-       char buf[32];
+       char buf[INET6_ADDRSTRLEN];
 
        vlist_simple_for_each_element(&ip->dns_servers, s, node) {
                str = inet_ntop(s->af, &s->addr, buf, sizeof(buf));
@@ -763,10 +948,11 @@ interface_write_resolv_conf(void)
        struct interface *iface;
        char *path = alloca(strlen(resolv_conf) + 5);
        FILE *f;
+       uint32_t crcold, crcnew;
 
        sprintf(path, "%s.tmp", resolv_conf);
        unlink(path);
-       f = fopen(path, "w");
+       f = fopen(path, "w+");
        if (!f) {
                D(INTERFACE, "Failed to open %s for writing\n", path);
                return;
@@ -787,8 +973,21 @@ interface_write_resolv_conf(void)
                if (!iface->proto_ip.no_dns)
                        write_resolv_conf_entries(f, &iface->proto_ip);
        }
+       fflush(f);
+       rewind(f);
+       crcnew = crc32_file(f);
        fclose(f);
-       if (rename(path, resolv_conf) < 0) {
+
+       crcold = crcnew + 1;
+       f = fopen(resolv_conf, "r");
+       if (f) {
+               crcold = crc32_file(f);
+               fclose(f);
+       }
+
+       if (crcold == crcnew) {
+               unlink(path);
+       } else if (rename(path, resolv_conf) < 0) {
                D(INTERFACE, "Failed to replace %s\n", resolv_conf);
                unlink(path);
        }
@@ -834,6 +1033,15 @@ void interface_ip_set_enabled(struct interface_ip_settings *ip, bool enabled)
                        system_del_route(dev, route);
                route->enabled = _enabled;
        }
+
+       struct device_prefix *c;
+       struct device_prefix_assignment *a;
+       list_for_each_entry(c, &prefixes, head)
+               list_for_each_entry(a, &c->assignments, head)
+                       if (!strcmp(a->name, ip->iface->name))
+                               interface_set_prefix_address(a, c, ip->iface, enabled);
+
+       set_ipv6_lo_policy(enabled, dev->ifindex);
 }
 
 void
@@ -889,4 +1097,42 @@ interface_ip_init(struct interface *iface)
        __interface_ip_init(&iface->proto_ip, iface);
        __interface_ip_init(&iface->config_ip, iface);
        vlist_init(&iface->host_routes, route_cmp, interface_update_host_route);
+
+}
+
+static void
+interface_ip_valid_until_handler(struct uloop_timeout *t)
+{
+       time_t now = system_get_rtime();
+       struct interface *iface;
+       vlist_for_each_element(&interfaces, iface, node) {
+               if (iface->state != IFS_UP)
+                       continue;
+
+               struct device_addr *addr, *addrp;
+               struct device_route *route, *routep;
+               struct device_prefix *pref, *prefp;
+
+               vlist_for_each_element_safe(&iface->proto_ip.addr, addr, node, addrp)
+                       if (addr->valid_until && addr->valid_until < now)
+                               vlist_delete(&iface->proto_ip.addr, &addr->node);
+
+               vlist_for_each_element_safe(&iface->proto_ip.route, route, node, routep)
+                       if (route->valid_until && route->valid_until < now)
+                               vlist_delete(&iface->proto_ip.route, &route->node);
+
+               vlist_for_each_element_safe(&iface->proto_ip.prefix, pref, node, prefp)
+                       if (pref->valid_until && pref->valid_until < now)
+                               vlist_delete(&iface->proto_ip.prefix, &pref->node);
+
+       }
+
+       uloop_timeout_set(t, 1000);
+}
+
+static void __init
+interface_ip_init_worker(void)
+{
+       valid_until_timeout.cb = interface_ip_valid_until_handler;
+       uloop_timeout_set(&valid_until_timeout, 1000);
 }