router: fix Lan host reachibility due to identical RIO and PIO prefixes (FS#3056)

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

diff --git a/src/router.c b/src/router.c
index 295bdfbb11fa363af7a223a5c329472f9d57825e..7198ee97cb357cf09624c427b40a0b74638f1c72 100644 (file)
--- a/src/router.c
+++ b/src/router.c
@@ -659,12 +659,22 @@ static int send_router_advert(struct interface *iface, const struct in6_addr *fr
        iov[IOV_RA_SEARCH].iov_base = (char *)search;
        iov[IOV_RA_SEARCH].iov_len = search_sz;
 
+       /*
+        * RFC7084 § 4.3 :
+        *    L-3:   An IPv6 CE router MUST advertise itself as a router for the
+        *           delegated prefix(es) (and ULA prefix if configured to provide
+        *           ULA addressing) using the "Route Information Option" specified
+        *           in Section 2.3 of [RFC4191].  This advertisement is
+        *           independent of having or not having IPv6 connectivity on the
+        *           WAN interface.
+        */
+
        for (ssize_t i = 0; i < addr_cnt; ++i) {
                struct odhcpd_ipaddr *addr = &addrs[i];
                struct nd_opt_route_info *tmp;
                uint32_t valid;
 
-               if (addr->dprefix > 64 || addr->dprefix == 0 || addr->valid <= (uint32_t)now) {
+               if (addr->dprefix >= 64 || addr->dprefix == 0 || addr->valid <= (uint32_t)now) {
                        syslog(LOG_INFO, "Address %s (dprefix %d, valid %u) not suitable as RA route on %s",
                                inet_ntop(AF_INET6, &addr->addr.in6, buf, sizeof(buf)),
                                addr->dprefix, addr->valid, iface->name);