router: allow RA prefix lifetime being set to leasetime value (FS#397)

[project/odhcpd.git] / src / router.c

diff --git a/src/router.c b/src/router.c
index 4ab06b6..dd3f09c 100644 (file)
--- a/src/router.c
+++ b/src/router.c
@@ -321,6 +321,8 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 
        for (ssize_t i = 0; i < ipcnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
+               uint32_t preferred = 0;
+               uint32_t valid = 0;
 
                if (addr->prefix > 96 || addr->valid <= (uint32_t)now) {
                        char namebuf[INET6_ADDRSTRLEN];
@@ -346,9 +348,23 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                        p = &adv.prefix[cnt++];
                }
 
-               if (addr->preferred > (uint32_t)now &&
-                               minvalid > TIME_LEFT(addr->valid, now))
-                       minvalid = TIME_LEFT(addr->valid, now);
+               if (addr->preferred > (uint32_t)now) {
+                       preferred = TIME_LEFT(addr->preferred, now);
+
+                       if (iface->ra_useleasetime &&
+                                       preferred > iface->dhcpv4_leasetime)
+                               preferred = iface->dhcpv4_leasetime;
+               }
+
+               valid = TIME_LEFT(addr->valid, now);
+               if (iface->ra_useleasetime) {
+                       if (valid > iface->dhcpv4_leasetime)
+                               valid = iface->dhcpv4_leasetime;
+               } else if (!preferred && valid < 7200)
+                       valid = 0;
+
+               if (minvalid > valid)
+                       minvalid = valid;
 
                if (!IN6_IS_ADDR_ULA(&addr->addr) || iface->default_router)
                        valid_prefix = true;
@@ -365,11 +381,8 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
                        p->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_AUTO;
                if (iface->ra_advrouter)
                        p->nd_opt_pi_flags_reserved |= ND_OPT_PI_FLAG_RADDR;
-               p->nd_opt_pi_valid_time = htonl(TIME_LEFT(addr->valid, now));
-               if (addr->preferred > (uint32_t)now)
-                       p->nd_opt_pi_preferred_time = htonl(TIME_LEFT(addr->preferred, now));
-               else if (addr->valid - now < 7200)
-                       p->nd_opt_pi_valid_time = 0;
+               p->nd_opt_pi_preferred_time = htonl(preferred);
+               p->nd_opt_pi_valid_time = htonl(valid);
        }
 
        // Calculate periodic transmit