zebra: link layer config and notification, implementation in zebra

zebra implements zebra api for configuring link layer information. that
can be an arp entry (for ipv4) or ipv6 neighbor discovery entry. This
can also be an ipv4/ipv6 entry associated to an underlay ipv4 address,
as it is used in gre point to multipoint interfaces.
this api will also be used as monitoring. an hash list is instantiated
into zebra (this is the vrf bitmap). each client interested in those entries
in a specific vrf, will listen for following messages: entries added, removed,
or who-has messages.

Signed-off-by: Philippe Guibert <philippe.guibert@6wind.com>

1 files changed, 81 insertions, 0 deletions

diff --git a/zebra/zapi_msg.c b/zebra/zapi_msg.c
index b482914418..304a6a03f1 100644
--- a/zebra/zapi_msg.c
+++ b/zebra/zapi_msg.c
@@ -974,6 +974,52 @@ void zsend_ipset_entry_notify_owner(const struct zebra_dplane_ctx *ctx,
 	zserv_send_message(client, s);
 }
 
+void zsend_nhrp_neighbor_notify(int cmd, struct interface *ifp,
+				struct ipaddr *ipaddr, int ndm_state,
+				void *mac, int macsize)
+{
+	struct stream *s;
+	struct listnode *node, *nnode;
+	struct zserv *client;
+	afi_t afi;
+
+	if (IS_ZEBRA_DEBUG_PACKET)
+		zlog_debug("%s: Notifying Neighbor entry (%u)",
+			   __PRETTY_FUNCTION__, cmd);
+
+	if (ipaddr->ipa_type == IPADDR_V4)
+		afi = AFI_IP;
+	else if (ipaddr->ipa_type == IPADDR_V6)
+		afi = AFI_IP6;
+	else
+		return;
+	for (ALL_LIST_ELEMENTS(zrouter.client_list, node, nnode, client)) {
+		if (!vrf_bitmap_check(client->nhrp_neighinfo[afi], ifp->vrf_id))
+			continue;
+
+		s = stream_new(ZEBRA_MAX_PACKET_SIZ);
+
+		zclient_create_header(s, cmd, ifp->vrf_id);
+		stream_putl(s, ifp->ifindex);
+		if (ipaddr->ipa_type == IPADDR_V4) {
+			stream_putw(s, AF_INET);
+			stream_put(s, &ipaddr->ip._v4_addr, IPV4_MAX_BYTELEN);
+		} else if (ipaddr->ipa_type == IPADDR_V6) {
+			stream_putw(s, AF_INET6);
+			stream_put(s, &ipaddr->ip._v6_addr, IPV6_MAX_BYTELEN);
+		} else
+			return;
+		stream_putl(s, ndm_state);
+		stream_putl(s, macsize);
+		if (mac)
+			stream_put(s, mac, macsize);
+		stream_putw_at(s, 0, stream_get_endp(s));
+
+		zserv_send_message(client, s);
+	}
+}
+
+
 /* Router-id is updated. Send ZEBRA_ROUTER_ID_UPDATE to client. */
 int zsend_router_id_update(struct zserv *client, afi_t afi, struct prefix *p,
 			   vrf_id_t vrf_id)
@@ -2277,6 +2323,7 @@ static void zread_vrf_unregister(ZAPI_HANDLER_ARGS)
 			vrf_bitmap_unset(client->redist[afi][i], zvrf_id(zvrf));
 		vrf_bitmap_unset(client->redist_default[afi], zvrf_id(zvrf));
 		vrf_bitmap_unset(client->ridinfo[afi], zvrf_id(zvrf));
+		vrf_bitmap_unset(client->nhrp_neighinfo[afi], zvrf_id(zvrf));
 	}
 }
 
@@ -3167,6 +3214,38 @@ stream_failure:
 	return;
 }
 
+static inline void zebra_neigh_register(ZAPI_HANDLER_ARGS)
+{
+	afi_t afi;
+
+	STREAM_GETW(msg, afi);
+	if (afi <= AFI_UNSPEC || afi >= AFI_MAX) {
+		zlog_warn(
+			"Invalid AFI %u while registering for neighbors notifications",
+			afi);
+		goto stream_failure;
+	}
+	vrf_bitmap_set(client->nhrp_neighinfo[afi], zvrf_id(zvrf));
+stream_failure:
+	return;
+}
+
+static inline void zebra_neigh_unregister(ZAPI_HANDLER_ARGS)
+{
+	afi_t afi;
+
+	STREAM_GETW(msg, afi);
+	if (afi <= AFI_UNSPEC || afi >= AFI_MAX) {
+		zlog_warn(
+			"Invalid AFI %u while unregistering from neighbor notifications",
+			afi);
+		goto stream_failure;
+	}
+	vrf_bitmap_unset(client->nhrp_neighinfo[afi], zvrf_id(zvrf));
+stream_failure:
+	return;
+}
+
 static inline void zread_iptable(ZAPI_HANDLER_ARGS)
 {
 	struct zebra_pbr_iptable *zpi =
@@ -3352,6 +3431,8 @@ void (*const zserv_handlers[])(ZAPI_HANDLER_ARGS) = {
 	[ZEBRA_ROUTE_NOTIFY_REQUEST] = zread_route_notify_request,
 	[ZEBRA_EVPN_REMOTE_NH_ADD] = zebra_evpn_proc_remote_nh,
 	[ZEBRA_EVPN_REMOTE_NH_DEL] = zebra_evpn_proc_remote_nh,
+	[ZEBRA_NHRP_NEIGH_REGISTER] = zebra_neigh_register,
+	[ZEBRA_NHRP_NEIGH_UNREGISTER] = zebra_neigh_unregister,
 };
 
 /*