dhcpv6-ia: fix border assignment size setting

The border assignment size is not updated by address list change events if
the interface is not configured as DHCPv6 server; therefore set the border
assignment size when an interface is enabled and configured as a DHCPv6
server in order to keep the assignment size in sync with the available
prefix sizes

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>

diff --git a/src/dhcpv6-ia.c b/src/dhcpv6-ia.c
index fa652ab9b2c63bf20d177d3e5721dccc4b7c9ebf..4ee6dd2639156bdc6310cb37efd5902913b24cc3 100644 (file)
--- a/src/dhcpv6-ia.c
+++ b/src/dhcpv6-ia.c
@@ -41,6 +41,7 @@
 
 static void dhcpv6_netevent_cb(unsigned long event, struct netevent_handler_info *info);
 static void free_dhcpv6_assignment(struct dhcpv6_assignment *c);
+static void set_border_assignment_size(struct interface *iface, struct dhcpv6_assignment *b);
 static void handle_addrlist_change(struct netevent_handler_info *info);
 static void start_reconf(struct dhcpv6_assignment *a);
 static void stop_reconf(struct dhcpv6_assignment *a);
@@ -72,11 +73,15 @@ int dhcpv6_setup_ia_interface(struct interface *iface, bool enable)
        }
 
        if (enable && iface->dhcpv6 == MODE_SERVER) {
+               struct dhcpv6_assignment *border;
+               struct lease *lease;
+
                if (!iface->ia_assignments.next)
                        INIT_LIST_HEAD(&iface->ia_assignments);
 
                if (list_empty(&iface->ia_assignments)) {
-                       struct dhcpv6_assignment *border = calloc(1, sizeof(*border));
+                       border = calloc(1, sizeof(*border));
+
                        if (!border) {
                                syslog(LOG_ERR, "Calloc failed for border on interface %s", iface->ifname);
                                return -1;
@@ -84,10 +89,12 @@ int dhcpv6_setup_ia_interface(struct interface *iface, bool enable)
 
                        border->length = 64;
                        list_add(&border->head, &iface->ia_assignments);
-               }
+               } else
+                       border = list_last_entry(&iface->ia_assignments, struct dhcpv6_assignment, head);
+
+               set_border_assignment_size(iface, border);
 
                /* Parse static entries */
-               struct lease *lease;
                list_for_each_entry(lease, &leases, head) {
                        /* Construct entry */
                        size_t duid_len = lease->duid_len ? lease->duid_len : 14;
@@ -489,6 +496,25 @@ static void apply_lease(struct interface *iface, struct dhcpv6_assignment *a, bo
        __apply_lease(iface, a, addrs, addrlen, add);
 }
 
+/* Set border assignment size based on the IPv6 address prefixes */
+static void set_border_assignment_size(struct interface *iface, struct dhcpv6_assignment *b)
+{
+       time_t now = odhcpd_time();
+       int minprefix = -1;
+
+       for (size_t i = 0; i < iface->addr6_len; ++i) {
+               if (iface->addr6[i].preferred > (uint32_t)now &&
+                               iface->addr6[i].prefix < 64 &&
+                               iface->addr6[i].prefix > minprefix)
+                       minprefix = iface->addr6[i].prefix;
+       }
+
+       if (minprefix > 32 && minprefix <= 64)
+               b->assigned = 1U << (64 - minprefix);
+       else
+               b->assigned = 0;
+}
+
 /* More data was received from TCP connection */
 static void managed_handle_pd_data(struct ustream *s, _unused int bytes_new)
 {
@@ -695,28 +721,18 @@ static void handle_addrlist_change(struct netevent_handler_info *info)
        struct interface *iface = info->iface;
        struct dhcpv6_assignment *c, *d, *border = list_last_entry(
                        &iface->ia_assignments, struct dhcpv6_assignment, head);
+       struct list_head reassign = LIST_HEAD_INIT(reassign);
        time_t now = odhcpd_time();
-       int minprefix = -1;
 
-       list_for_each_entry(c, &iface->ia_assignments, head)
+       list_for_each_entry(c, &iface->ia_assignments, head) {
                if (c != border && iface->ra_managed == RA_MANAGED_NO_MFLAG
                                && (c->flags & OAF_BOUND))
                        __apply_lease(iface, c, info->addrs_old.addrs,
                                        info->addrs_old.len, false);
-
-       for (size_t i = 0; i < iface->addr6_len; ++i) {
-               if (iface->addr6[i].preferred > (uint32_t)now &&
-                               iface->addr6[i].prefix < 64 &&
-                               iface->addr6[i].prefix > minprefix)
-                       minprefix = iface->addr6[i].prefix;
        }
 
-       if (minprefix > 32 && minprefix <= 64)
-               border->assigned = 1U << (64 - minprefix);
-       else
-               border->assigned = 0;
+       set_border_assignment_size(iface, border);
 
-       struct list_head reassign = LIST_HEAD_INIT(reassign);
        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)
@@ -728,10 +744,11 @@ static void handle_addrlist_change(struct netevent_handler_info *info)
                        apply_lease(iface, c, true);
 
                if (c->accept_reconf && c->reconf_cnt == 0) {
+                       struct dhcpv6_assignment *a;
+
                        start_reconf(c);
 
                        /* Leave all other assignments of that client alone */
-                       struct dhcpv6_assignment *a;
                        list_for_each_entry(a, &iface->ia_assignments, head)
                                if (a != c && a->clid_len == c->clid_len &&
                                                !memcmp(a->clid_data, c->clid_data, a->clid_len))