ndisc: add logic for acting as a router

src/ndisc/nm-fake-ndisc.c

@@ -373,6 +373,7 @@ nm_fake_ndisc_new (int ifindex, const char *ifname)
 	return g_object_new (NM_TYPE_FAKE_NDISC,
 	                     NM_NDISC_IFINDEX, ifindex,
 	                     NM_NDISC_IFNAME, ifname,
+	                     NM_NDISC_NODE_TYPE, (int) NM_NDISC_NODE_TYPE_HOST,
 	                     NULL);
 }
 

src/ndisc/nm-lndp-ndisc.c

@@ -380,6 +380,7 @@ nm_lndp_ndisc_new (NMPlatform *platform,
 	                      NM_NDISC_IFNAME, ifname,
 	                      NM_NDISC_NETWORK_ID, network_id,
 	                      NM_NDISC_ADDR_GEN_MODE, (int) addr_gen_mode,
+	                      NM_NDISC_NODE_TYPE, (int) NM_NDISC_NODE_TYPE_HOST,
 	                      NM_NDISC_MAX_ADDRESSES, ipv6_sysctl_get (platform, ifname,
 	                                                               "max_addresses",
 	                                                               0, G_MAXINT32, NM_NDISC_MAX_ADDRESSES_DEFAULT),

src/ndisc/nm-ndisc-private.h

@@ -37,6 +37,7 @@ struct _NMNDiscDataInternal {
 typedef struct _NMNDiscDataInternal NMNDiscDataInternal;
 
 void nm_ndisc_ra_received (NMNDisc *ndisc, guint32 now, NMNDiscConfigMap changed);
+void nm_ndisc_rs_received (NMNDisc *ndisc);
 
 gboolean nm_ndisc_add_gateway              (NMNDisc *ndisc, const NMNDiscGateway *new);
 gboolean nm_ndisc_complete_and_add_address (NMNDisc *ndisc, NMNDiscAddress *new);

src/ndisc/nm-ndisc.c

@@ -41,9 +41,18 @@ struct _NMNDiscPrivate {
 	/* this *must* be the first field. */
 	NMNDiscDataInternal rdata;
 
+	union {
 		gint32 solicitations_left;
+		gint32 announcements_left;
+	};
+	union {
 		guint send_rs_id;
+		guint send_ra_id;
+	};
+	union {
 		gint32 last_rs;
+		gint32 last_ra;
+	};
 	guint ra_timeout_id;  /* first RA timeout */
 	guint timeout_id;   /* prefix/dns/etc lifetime timeout */
 	char *last_error;
@@ -58,6 +67,7 @@ struct _NMNDiscPrivate {
 	gint32 max_addresses;
 	gint32 router_solicitations;
 	gint32 router_solicitation_interval;
+	NMNDiscNodeType node_type;
 
 	NMPlatform *platform;
 	NMPNetns *netns;
@@ -75,6 +85,7 @@ NM_GOBJECT_PROPERTIES_DEFINE_BASE (
 	PROP_MAX_ADDRESSES,
 	PROP_ROUTER_SOLICITATIONS,
 	PROP_ROUTER_SOLICITATION_INTERVAL,
+	PROP_NODE_TYPE,
 );
 
 enum {
@@ -139,6 +150,14 @@ nm_ndisc_get_ifname (NMNDisc *self)
 	return NM_NDISC_GET_PRIVATE (self)->ifname;
 }
 
+NMNDiscNodeType
+nm_ndisc_get_node_type (NMNDisc *self)
+{
+	g_return_val_if_fail (NM_IS_NDISC (self), NM_NDISC_NODE_TYPE_INVALID);
+
+	return NM_NDISC_GET_PRIVATE (self)->node_type;
+}
+
 /*****************************************************************************/
 
 static const NMNDiscData *
@@ -259,19 +278,13 @@ complete_address (NMNDisc *ndisc, NMNDiscAddress *addr)
 	return FALSE;
 }
 
-gboolean
+static gboolean
-nm_ndisc_complete_and_add_address (NMNDisc *ndisc, NMNDiscAddress *new)
+nm_ndisc_add_address (NMNDisc *ndisc, const NMNDiscAddress *new)
 {
-	NMNDiscPrivate *priv;
+	NMNDiscPrivate *priv = NM_NDISC_GET_PRIVATE (ndisc);
-	NMNDiscDataInternal *rdata;
+	NMNDiscDataInternal *rdata = &priv->rdata;
 	int i;
 
-	if (!complete_address (ndisc, new))
-		return FALSE;
-
-	priv = NM_NDISC_GET_PRIVATE (ndisc);
-	rdata = &priv->rdata;
-
 	for (i = 0; i < rdata->addresses->len; i++) {
 		NMNDiscAddress *item = &g_array_index (rdata->addresses, NMNDiscAddress, i);
 
@@ -302,6 +315,15 @@ nm_ndisc_complete_and_add_address (NMNDisc *ndisc, NMNDiscAddress *new)
 	return !!new->lifetime;
 }
 
+gboolean
+nm_ndisc_complete_and_add_address (NMNDisc *ndisc, NMNDiscAddress *new)
+{
+	if (!complete_address (ndisc, new))
+		return FALSE;
+
+	return nm_ndisc_add_address (ndisc, new);
+}
+
 gboolean
 nm_ndisc_add_route (NMNDisc *ndisc, const NMNDiscRoute *new)
 {
@@ -473,7 +495,7 @@ send_rs_timeout (NMNDisc *ndisc)
 }
 
 static void
-solicit (NMNDisc *ndisc)
+solicit_routers (NMNDisc *ndisc)
 {
 	NMNDiscPrivate *priv = NM_NDISC_GET_PRIVATE (ndisc);
 	gint64 next, now;
@@ -482,7 +504,6 @@ solicit (NMNDisc *ndisc)
 		return;
 
 	now = nm_utils_get_monotonic_timestamp_s ();
-
 	priv->solicitations_left = priv->router_solicitations;
 
 	next = (((gint64) priv->last_rs) + priv->router_solicitation_interval) - now;
@@ -492,8 +513,114 @@ solicit (NMNDisc *ndisc)
 	priv->send_rs_id = g_timeout_add_seconds ((guint32) next, (GSourceFunc) send_rs_timeout, ndisc);
 }
 
+static gboolean
+announce_router (NMNDisc *ndisc)
+{
+	nm_auto_pop_netns NMPNetns *netns = NULL;
+	NMNDiscClass *klass = NM_NDISC_GET_CLASS (ndisc);
+	NMNDiscPrivate *priv = NM_NDISC_GET_PRIVATE (ndisc);
+	GError *error = NULL;
+
+	if (!nm_ndisc_netns_push (ndisc, &netns))
+		return G_SOURCE_REMOVE;
+
+	priv->last_ra = nm_utils_get_monotonic_timestamp_s ();
+	if (klass->send_ra (ndisc, &error)) {
+		_LOGD ("router advertisement sent");
+		g_clear_pointer (&priv->last_error, g_free);
+	} else {
+		_MAYBE_WARN ("failure sending router advertisement: %s", error->message);
+		g_clear_error (&error);
+	}
+
+	if (--priv->announcements_left) {
+		_LOGD ("will resend an initial router advertisement");
+
+		/* Schedule next initial announcement retransmit. */
+		priv->send_ra_id = g_timeout_add_seconds (g_random_int_range (0, NM_NDISC_ROUTER_ADVERT_INITIAL_INTERVAL),
+		                                          (GSourceFunc) announce_router, ndisc);
+	} else {
+		_LOGD ("will send an unsolicited router advertisement");
+
+		/* Schedule next unsolicited announcement. */
+		priv->announcements_left = 1;
+		priv->send_ra_id = g_timeout_add_seconds (NM_NDISC_ROUTER_ADVERT_MAX_INTERVAL,
+		                                          (GSourceFunc) announce_router,
+		                                          ndisc);
+	}
+
+	return G_SOURCE_REMOVE;
+}
+
+static void
+announce_router_initial (NMNDisc *ndisc)
+{
+	NMNDiscPrivate *priv = NM_NDISC_GET_PRIVATE (ndisc);
+
+	_LOGD ("will send an initial router advertisement");
+
+	/* Retry three more times. */
+	priv->announcements_left = NM_NDISC_ROUTER_ADVERTISEMENTS_DEFAULT;
+
+	/* Unschedule an unsolicited resend if we are allowed to send now. */
+	if (G_LIKELY (nm_utils_get_monotonic_timestamp_s () - priv->last_ra > NM_NDISC_ROUTER_ADVERT_DELAY))
+		nm_clear_g_source (&priv->send_ra_id);
+
+	/* Schedule the initial send rather early. Clamp the delay by minimal
+	 * delay and not the initial advert internal so that we start fast. */
+	if (G_LIKELY (!priv->send_ra_id)) {
+		priv->send_ra_id = g_timeout_add_seconds (g_random_int_range (0, NM_NDISC_ROUTER_ADVERT_DELAY),
+		                                          (GSourceFunc) announce_router, ndisc);
+	}
+}
+
+static void
+announce_router_solicited (NMNDisc *ndisc)
+{
+	NMNDiscPrivate *priv = NM_NDISC_GET_PRIVATE (ndisc);
+
+	_LOGD ("will send an solicited router advertisement");
+
+	/* Unschedule an unsolicited resend if we are allowed to send now. */
+	if (nm_utils_get_monotonic_timestamp_s () - priv->last_ra > NM_NDISC_ROUTER_ADVERT_DELAY)
+		nm_clear_g_source (&priv->send_ra_id);
+
+	if (!priv->send_ra_id) {
+		priv->send_ra_id = g_timeout_add (g_random_int_range (0, 500),
+		                                  (GSourceFunc) announce_router, ndisc);
+	}
+}
+
 /*****************************************************************************/
 
+void
+nm_ndisc_set_config (NMNDisc *ndisc,
+                     const GArray *addresses,
+                     const GArray *dns_servers,
+                     const GArray *dns_domains)
+{
+	int changed = FALSE;
+	guint i;
+
+	for (i = 0; i < addresses->len; i++) {
+		if (nm_ndisc_add_address (ndisc, &g_array_index (addresses, NMNDiscAddress, i)))
+			changed = TRUE;
+	}
+
+	for (i = 0; i < dns_servers->len; i++) {
+		if (nm_ndisc_add_dns_server (ndisc, &g_array_index (dns_servers, NMNDiscDNSServer, i)))
+			changed = TRUE;
+	}
+
+	for (i = 0; i < dns_domains->len; i++) {
+		if (nm_ndisc_add_dns_domain (ndisc, &g_array_index (dns_domains, NMNDiscDNSDomain, i)))
+			changed = TRUE;
+	}
+
+	if (changed)
+		announce_router_initial (ndisc);
+}
+
 /**
  * nm_ndisc_set_iid:
  * @ndisc: the #NMNDisc
@@ -534,7 +661,7 @@ nm_ndisc_set_iid (NMNDisc *ndisc, const NMUtilsIPv6IfaceId iid)
 			_LOGD ("IPv6 interface identifier changed, flushing addresses");
 			g_array_remove_range (rdata->addresses, 0, rdata->addresses->len);
 			_emit_config_change (ndisc, NM_NDISC_CONFIG_ADDRESSES);
-			solicit (ndisc);
+			solicit_routers (ndisc);
 		}
 		return TRUE;
 	}
@@ -568,14 +695,22 @@ nm_ndisc_start (NMNDisc *ndisc)
 	if (!nm_ndisc_netns_push (ndisc, &netns))
 		return;
 
+	klass->start (ndisc);
+
+	switch (priv->node_type) {
+	case NM_NDISC_NODE_TYPE_HOST:
 		ra_wait_secs = (((gint64) priv->router_solicitations) * priv->router_solicitation_interval) + 1;
 		ra_wait_secs = CLAMP (ra_wait_secs, 30, 120);
 		priv->ra_timeout_id = g_timeout_add_seconds (ra_wait_secs, ndisc_ra_timeout_cb, ndisc);
 		_LOGD ("scheduling RA timeout in %d seconds", (int) ra_wait_secs);
-
+		solicit_routers (ndisc);
-	klass->start (ndisc);
+		break;
-
+	case NM_NDISC_NODE_TYPE_ROUTER:
-	solicit (ndisc);
+		announce_router_initial (ndisc);
+		break;
+	default:
+		g_assert_not_reached ();
+	}
 }
 
 void
@@ -780,7 +915,7 @@ clean_dns_servers (NMNDisc *ndisc, guint32 now, NMNDiscConfigMap *changed, guint
 			g_array_remove_index (rdata->dns_servers, i--);
 			*changed |= NM_NDISC_CONFIG_DNS_SERVERS;
 		} else if (now >= refresh)
-			solicit (ndisc);
+			solicit_routers (ndisc);
 		else if (*nextevent > refresh)
 			*nextevent = refresh;
 	}
@@ -806,7 +941,7 @@ clean_dns_domains (NMNDisc *ndisc, guint32 now, NMNDiscConfigMap *changed, guint
 			g_array_remove_index (rdata->dns_domains, i--);
 			*changed |= NM_NDISC_CONFIG_DNS_DOMAINS;
 		} else if (now >= refresh)
-			solicit (ndisc);
+			solicit_routers (ndisc);
 		else if (*nextevent > refresh)
 			*nextevent = refresh;
 	}
@@ -862,6 +997,15 @@ nm_ndisc_ra_received (NMNDisc *ndisc, guint32 now, NMNDiscConfigMap changed)
 	check_timestamps (ndisc, now, changed);
 }
 
+void
+nm_ndisc_rs_received (NMNDisc *ndisc)
+{
+	NMNDiscPrivate *priv = NM_NDISC_GET_PRIVATE (ndisc);
+
+	g_clear_pointer (&priv->last_error, g_free);
+	announce_router_solicited (ndisc);
+}
+
 /*****************************************************************************/
 
 static void
@@ -926,6 +1070,10 @@ set_property (GObject *object, guint prop_id,
 		/* construct-only */
 		priv->router_solicitation_interval = g_value_get_int (value);
 		break;
+	case PROP_NODE_TYPE:
+		/* construct-only */
+		priv->node_type = g_value_get_int (value);
+		break;
 	default:
 		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 		break;
@@ -965,6 +1113,7 @@ dispose (GObject *object)
 
 	nm_clear_g_source (&priv->ra_timeout_id);
 	nm_clear_g_source (&priv->send_rs_id);
+	nm_clear_g_source (&priv->send_ra_id);
 	g_clear_pointer (&priv->last_error, g_free);
 
 	nm_clear_g_source (&priv->timeout_id);
@@ -1059,6 +1208,12 @@ nm_ndisc_class_init (NMNDiscClass *klass)
 	                      G_PARAM_WRITABLE |
 	                      G_PARAM_CONSTRUCT_ONLY |
 	                      G_PARAM_STATIC_STRINGS);
+	obj_properties[PROP_NODE_TYPE] =
+	    g_param_spec_int (NM_NDISC_NODE_TYPE, "", "",
+	                      NM_NDISC_NODE_TYPE_INVALID, NM_NDISC_NODE_TYPE_ROUTER, NM_NDISC_NODE_TYPE_INVALID,
+	                      G_PARAM_WRITABLE |
+	                      G_PARAM_CONSTRUCT_ONLY |
+	                      G_PARAM_STATIC_STRINGS);
 	g_object_class_install_properties (object_class, _PROPERTY_ENUMS_LAST, obj_properties);
 
 	signals[CONFIG_CHANGED] =

src/ndisc/nm-ndisc.h

@@ -40,6 +40,7 @@
 #define NM_NDISC_NETWORK_ID     "network-id"
 #define NM_NDISC_ADDR_GEN_MODE  "addr-gen-mode"
 #define NM_NDISC_STABLE_TYPE    "stable-type"
+#define NM_NDISC_NODE_TYPE      "node-type"
 #define NM_NDISC_MAX_ADDRESSES  "max-addresses"
 #define NM_NDISC_ROUTER_SOLICITATIONS "router-solicitations"
 #define NM_NDISC_ROUTER_SOLICITATION_INTERVAL "router-solicitation-interval"
@@ -108,9 +109,19 @@ typedef enum {
 	NM_NDISC_CONFIG_MTU                                 = 1 << 7,
 } NMNDiscConfigMap;
 
+typedef enum {
+	NM_NDISC_NODE_TYPE_INVALID,
+	NM_NDISC_NODE_TYPE_HOST,
+	NM_NDISC_NODE_TYPE_ROUTER,
+} NMNDiscNodeType;
+
 #define NM_NDISC_MAX_ADDRESSES_DEFAULT 16
 #define NM_NDISC_ROUTER_SOLICITATIONS_DEFAULT 3          /* RFC4861 MAX_RTR_SOLICITATIONS */
 #define NM_NDISC_ROUTER_SOLICITATION_INTERVAL_DEFAULT 4  /* RFC4861 RTR_SOLICITATION_INTERVAL */
+#define NM_NDISC_ROUTER_ADVERTISEMENTS_DEFAULT 3         /* RFC4861 MAX_INITIAL_RTR_ADVERTISEMENTS */
+#define NM_NDISC_ROUTER_ADVERT_DELAY 3                   /* RFC4861 MIN_DELAY_BETWEEN_RAS */
+#define NM_NDISC_ROUTER_ADVERT_INITIAL_INTERVAL 16       /* RFC4861 MAX_INITIAL_RTR_ADVERT_INTERVAL */
+#define NM_NDISC_ROUTER_ADVERT_MAX_INTERVAL 600          /* RFC4861 MaxRtrAdvInterval default */
 
 struct _NMNDiscPrivate;
 struct _NMNDiscDataInternal;
@@ -152,16 +163,22 @@ typedef struct {
 
 	void (*start) (NMNDisc *ndisc);
 	gboolean (*send_rs) (NMNDisc *ndisc, GError **error);
+	gboolean (*send_ra) (NMNDisc *ndisc, GError **error);
 } NMNDiscClass;
 
 GType nm_ndisc_get_type (void);
 
 int nm_ndisc_get_ifindex (NMNDisc *self);
 const char *nm_ndisc_get_ifname (NMNDisc *self);
+NMNDiscNodeType nm_ndisc_get_node_type (NMNDisc *self);
 
 gboolean nm_ndisc_set_iid (NMNDisc *ndisc, const NMUtilsIPv6IfaceId iid);
 void nm_ndisc_start (NMNDisc *ndisc);
 void nm_ndisc_dad_failed (NMNDisc *ndisc, struct in6_addr *address);
+void nm_ndisc_set_config (NMNDisc *ndisc,
+                          const GArray *addresses,
+                          const GArray *dns_servers,
+                          const GArray *dns_domains);
 
 NMPlatform *nm_ndisc_get_platform (NMNDisc *self);
 NMPNetns *nm_ndisc_netns_get (NMNDisc *self);