Remove unsolicited unicast RAs, adjust intervals

6 files changed, 33 insertions, 104 deletions

diff --git a/src/config.c b/src/config.c
index f9ad3b8..7d870f1 100644
--- a/src/config.c
+++ b/src/config.c
@@ -40,6 +40,7 @@ enum {
 	IFACE_ATTR_RA_OFFLINK,
 	IFACE_ATTR_RA_PREFERENCE,
 	IFACE_ATTR_RA_ADVROUTER,
+	IFACE_ATTR_RA_MAXINTERVAL,
 	IFACE_ATTR_PD_MANAGER,
 	IFACE_ATTR_PD_CER,
 	IFACE_ATTR_NDPROXY_ROUTING,
@@ -74,6 +75,7 @@ static const struct blobmsg_policy iface_attrs[IFACE_ATTR_MAX] = {
 	[IFACE_ATTR_RA_OFFLINK] = { .name = "ra_offlink", .type = BLOBMSG_TYPE_BOOL },
 	[IFACE_ATTR_RA_PREFERENCE] = { .name = "ra_preference", .type = BLOBMSG_TYPE_STRING },
 	[IFACE_ATTR_RA_ADVROUTER] = { .name = "ra_advrouter", .type = BLOBMSG_TYPE_BOOL },
+	[IFACE_ATTR_RA_MAXINTERVAL] = { .name = "ra_maxinterval", .type = BLOBMSG_TYPE_INT32 },
 	[IFACE_ATTR_NDPROXY_ROUTING] = { .name = "ndproxy_routing", .type = BLOBMSG_TYPE_BOOL },
 	[IFACE_ATTR_NDPROXY_SLAVE] = { .name = "ndproxy_slave", .type = BLOBMSG_TYPE_BOOL },
 };
@@ -515,6 +517,9 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 	if ((c = tb[IFACE_ATTR_RA_ADVROUTER]))
 		iface->ra_advrouter = blobmsg_get_bool(c);
 
+	if ((c = tb[IFACE_ATTR_RA_MAXINTERVAL]))
+		iface->ra_maxinterval = blobmsg_get_u32(c);
+
 	if ((c = tb[IFACE_ATTR_RA_PREFERENCE])) {
 		const char *prio = blobmsg_get_string(c);
 
diff --git a/src/ndp.c b/src/ndp.c
index d5e9a39..d1683b9 100644
--- a/src/ndp.c
+++ b/src/ndp.c
@@ -324,11 +324,6 @@ static void handle_rtnetlink(_unused void *addr, void *data, size_t len,
 		if (!iface)
 			continue;
 
-		// Keep-alive neighbor entries for RA sending
-		if (nh->nlmsg_type == RTM_DELNEIGH && !(ndm->ndm_state & NUD_FAILED) &&
-				addr && IN6_IS_ADDR_LINKLOCAL(addr) && iface->ra == RELAYD_SERVER)
-			ping6(addr, iface);
-
 		// Address not specified or unrelated
 		if (!addr || IN6_IS_ADDR_LINKLOCAL(addr) ||
 				IN6_IS_ADDR_MULTICAST(addr))
diff --git a/src/odhcpd.c b/src/odhcpd.c
index c411542..5774a4f 100644
--- a/src/odhcpd.c
+++ b/src/odhcpd.c
@@ -188,61 +188,6 @@ ssize_t odhcpd_send(int socket, struct sockaddr_in6 *dest,
 }
 
 
-int odhcpd_iterate_interface_neighbors(const struct interface *iface,
-		void(*cb_neigh)(const struct in6_addr *addr,
-				const struct interface *iface, void *data), void *data)
-{
-	struct {
-		struct nlmsghdr nhm;
-		struct ndmsg ndm;
-	} req = {{sizeof(req), RTM_GETNEIGH, NLM_F_REQUEST | NLM_F_DUMP,
-			++rtnl_seq, 0}, {AF_INET6, 0, 0, iface->ifindex, 0, 0, 0}};
-
-	if (send(rtnl_socket, &req, sizeof(req), 0) < (ssize_t)sizeof(req))
-		return -1;
-
-	uint8_t buf[8192];
-	ssize_t len = 0;
-
-	for (struct nlmsghdr *nhm = NULL; ; nhm = NLMSG_NEXT(nhm, len)) {
-		while (len < 0 || !NLMSG_OK(nhm, (size_t)len)) {
-			len = recv(rtnl_socket, buf, sizeof(buf), 0);
-			nhm = (struct nlmsghdr*)buf;
-			if (len < 0 || !NLMSG_OK(nhm, (size_t)len)) {
-				if (errno == EINTR)
-					continue;
-				else
-					return -1;
-			}
-		}
-
-		if (nhm->nlmsg_type != RTM_NEWNEIGH)
-			break;
-
-		struct ndmsg *ndm = NLMSG_DATA(nhm);
-		if (ndm->ndm_ifindex != iface->ifindex ||
-				!(ndm->ndm_state & (NUD_STALE | NUD_REACHABLE | NUD_PERMANENT)))
-			continue;
-
-		struct rtattr *rta = (struct rtattr*)&ndm[1];
-		size_t alen = NLMSG_PAYLOAD(nhm, sizeof(*ndm));
-
-		while (RTA_OK(rta, alen)) {
-			if (rta->rta_type == NDA_DST &&
-					RTA_PAYLOAD(rta) == sizeof(struct in6_addr)) {
-				cb_neigh(RTA_DATA(rta), iface, data);
-				break;
-			} else {
-				rta = RTA_NEXT(rta, alen);
-			}
-		}
-
-	}
-
-	return 0;
-}
-
-
 // Detect an IPV6-address currently assigned to the given interface
 ssize_t odhcpd_get_interface_addresses(int ifindex,
 		struct odhcpd_ipaddr *addrs, size_t cnt)
diff --git a/src/odhcpd.h b/src/odhcpd.h
index 729b629..ab24674 100644
--- a/src/odhcpd.h
+++ b/src/odhcpd.h
@@ -143,6 +143,7 @@ struct interface {
 	int default_router;
 	int managed;
 	int route_preference;
+	int ra_maxinterval;
 
 	// DHCPv4
 	struct in_addr dhcpv4_start;
@@ -203,10 +204,6 @@ void odhcpd_hexlify(char *dst, const uint8_t *src, size_t len);
 int odhcpd_bmemcmp(const void *av, const void *bv, size_t bits);
 void odhcpd_bmemcpy(void *av, const void *bv, size_t bits);
 
-int odhcpd_iterate_interface_neighbors(const struct interface *iface,
-		void(*cb_neigh)(const struct in6_addr *addr,
-				const struct interface *iface, void *data), void *data);
-
 int config_parse_interface(void *data, size_t len, const char *iname, bool overwrite);
 
 #ifdef WITH_UBUS
diff --git a/src/router.c b/src/router.c
index a66f65f..e3a9aa9 100644
--- a/src/router.c
+++ b/src/router.c
@@ -206,20 +206,6 @@ static bool parse_routes(struct odhcpd_ipaddr *n, ssize_t len)
 	return found_default;
 }
 
-// Unicsat RAs
-static void send_neigh_ra(const struct in6_addr *addr,
-		const struct interface *iface, void *data)
-{
-	struct sockaddr_in6 dest = {
-		.sin6_family = AF_INET6,
-		.sin6_addr = *addr,
-		.sin6_scope_id = iface->ifindex,
-	};
-	if (IN6_IS_ADDR_LINKLOCAL(addr))
-		odhcpd_send(router_event.uloop.fd, &dest, data, RA_IOV_LEN, iface);
-}
-
-
 // Router Advert server mode
 static uint64_t send_router_advert(struct interface *iface, const struct in6_addr *from)
 {
@@ -258,7 +244,8 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 	// If not currently shutting down
 	struct odhcpd_ipaddr addrs[RELAYD_MAX_PREFIXES];
 	ssize_t ipcnt = 0;
-	uint64_t maxpreferred = 0;
+	uint64_t minvalid = UINT64_MAX;
+	uint64_t maxvalid = 0;
 
 	// If not shutdown
 	if (iface->timer_rs.cb) {
@@ -267,12 +254,10 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 
 		// Check default route
 		if (parse_routes(addrs, ipcnt) || iface->default_router > 1)
-			adv.h.nd_ra_router_lifetime =
-					htons(3 * MaxRtrAdvInterval);
+			adv.h.nd_ra_router_lifetime = 1;
 	}
 
 	// Construct Prefix Information options
-	bool have_public = false;
 	size_t cnt = 0;
 
 	struct in6_addr dns_pref = IN6ADDR_ANY_INIT, *dns_addr = &dns_pref;
@@ -284,8 +269,8 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 		if (addr->prefix > 96)
 			continue; // Address not suitable
 
-		if (addr->preferred > MaxPreferredTime)
-			addr->preferred = MaxPreferredTime;
+		if (addr->preferred > MaxValidTime)
+			addr->preferred = MaxValidTime;
 
 		if (addr->valid > MaxValidTime)
 			addr->valid = MaxValidTime;
@@ -305,13 +290,16 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 			p = &adv.prefix[cnt++];
 		}
 
-		if ((addr->addr.s6_addr[0] & 0xfe) != 0xfc && addr->preferred > 0) {
-			have_public = true;
+		if (addr->preferred > 0) {
+			if (minvalid > 1000ULL * addr->valid)
+				minvalid = 1000ULL * addr->valid;
 
-			if (maxpreferred < 1000 * addr->preferred)
-				maxpreferred = 1000 * addr->preferred;
+			if (maxvalid < 1000ULL * addr->valid && (iface->default_router ||
+					(addr->addr.s6_addr[0] & 0xfe) != 0xfc))
+				maxvalid = 1000ULL * addr->valid;
 		}
 
+
 		odhcpd_bmemcpy(&p->nd_opt_pi_prefix, &addr->addr,
 				(iface->ra_advrouter) ? 128 : addr->prefix);
 		p->nd_opt_pi_type = ND_OPT_PREFIX_INFORMATION;
@@ -333,7 +321,7 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 		}
 	}
 
-	if (!have_public && !iface->default_router && adv.h.nd_ra_router_lifetime) {
+	if (maxvalid && !iface->default_router && adv.h.nd_ra_router_lifetime) {
 		syslog(LOG_WARNING, "A default route is present but there is no public prefix "
 				"on %s thus we don't announce a default route!", iface->ifname);
 		adv.h.nd_ra_router_lifetime = 0;
@@ -434,20 +422,23 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 
 	// Calculate periodic transmit
 	int msecs = 0;
-	uint32_t maxival = MaxRtrAdvInterval * 1000;
-	uint32_t minival = MinRtrAdvInterval * 1000;
+	uint32_t maxival = iface->ra_maxinterval * 1000;
+	uint32_t minival;
+
+	if (maxival < 4000 || maxival > MaxRtrAdvInterval * 1000)
+		maxival = MaxRtrAdvInterval * 1000;
+
+	if (minvalid < maxival / 3) {
+		maxival = minvalid / 3;
 
-	if (maxpreferred > 0 && maxival > maxpreferred / 2) {
-		maxival = maxpreferred / 2;
 		if (maxival < 4000)
 			maxival = 4000;
-
-		if (maxival >= 9000)
-			minival = maxival / 3;
-		else
-			minival = (maxival * 3) / 4;
 	}
 
+	minival = (maxival * 3) / 4;
+	if (adv.h.nd_ra_router_lifetime)
+		adv.h.nd_ra_router_lifetime = htons(maxvalid);
+
 	odhcpd_urandom(&msecs, sizeof(msecs));
 	msecs = (labs(msecs) % (maxival - minival)) + minival;
 
@@ -468,8 +459,6 @@ static uint64_t send_router_advert(struct interface *iface, const struct in6_add
 
 	if (from && !IN6_IS_ADDR_UNSPECIFIED(from))
 		dest.sin6_addr = *from;
-	else
-		odhcpd_iterate_interface_neighbors(iface, send_neigh_ra, iov);
 
 	odhcpd_send(router_event.uloop.fd,
 			&dest, iov, ARRAY_SIZE(iov), iface);
diff --git a/src/router.h b/src/router.h
index 1e8649c..db8ab9d 100644
--- a/src/router.h
+++ b/src/router.h
@@ -30,10 +30,8 @@ struct icmpv6_opt {
 	(void*)(opt + opt->len) <= (void*)(end); opt += opt->len)
 
 
-#define MaxRtrAdvInterval 600
-#define MinRtrAdvInterval (MaxRtrAdvInterval / 3)
-#define MaxValidTime 7200
-#define MaxPreferredTime  (3 * MaxRtrAdvInterval)
+#define MaxRtrAdvInterval 1800
+#define MaxValidTime 65535
 
 #define ND_RA_FLAG_PROXY	0x4
 #define ND_RA_PREF_HIGH	(1 << 3)