zebra: handler for configuring neighbor table

neighbor table api in zebra is added. a netlink api is created for that.
the handler is called from the api defined in the previous commit.

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

4 files changed, 81 insertions, 0 deletions

diff --git a/zebra/rt.h b/zebra/rt.h
index f79ddbe95..01d324616 100644
--- a/zebra/rt.h
+++ b/zebra/rt.h
@@ -81,6 +81,7 @@ extern int mpls_kernel_init(void);
 extern uint32_t kernel_get_speed(struct interface *ifp, int *error);
 extern int kernel_get_ipmr_sg_stats(struct zebra_vrf *zvrf, void *mroute);
 
+extern int kernel_configure_arp(struct interface *ifp, int family, ns_id_t ns_id);
 /*
  * Southbound Initialization routines to get initial starting
  * state.
diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c
index 90d809475..a7fbbf133 100644
--- a/zebra/rt_netlink.c
+++ b/zebra/rt_netlink.c
@@ -1537,6 +1537,52 @@ static void _netlink_mpls_debug(int cmd, uint32_t label, const char *routedesc)
 			   routedesc, nl_msg_type_to_str(cmd), label);
 }
 
+static int netlink_configure_arp(struct interface *ifp, int family, ns_id_t ns_id)
+{
+	struct {
+		struct nlmsghdr n;
+		struct ndtmsg ndtm;
+		char buf[256];
+	} req;
+	struct zebra_ns *zns = zebra_ns_lookup(ns_id);
+	struct rtattr *nest;
+	uint32_t val;
+
+	memset(&req, 0, sizeof(req));
+
+	req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndtmsg));
+	req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_REPLACE;
+	req.n.nlmsg_type = RTM_SETNEIGHTBL;
+	req.n.nlmsg_pid = zns->netlink_cmd.snl.nl_pid;
+
+	req.ndtm.ndtm_family = family;
+
+	nl_attr_put(&req.n, sizeof(req), NDTA_NAME, family == AF_INET ? "arp_cache" :
+		    "ndisc_cache", 10);
+
+	nest = nl_attr_nest(&req.n, sizeof(req), NDTA_PARMS);
+	if (nest == NULL)
+		return;
+	if (!nl_attr_put(&req.n, sizeof(req), NDTPA_IFINDEX, &ifp->ifindex,
+			 sizeof(ifp->ifindex)))
+		return 0;
+	val = 1;
+	if (!nl_attr_put(&req.n, sizeof(req), NDTPA_APP_PROBES, &val,
+			 sizeof(val)))
+		return 0;
+	val = 0;
+	if (!nl_attr_put(&req.n, sizeof(req), NDTPA_MCAST_PROBES, &val,
+			 sizeof(val)))
+		return 0;
+	if (!nl_attr_put(&req.n, sizeof(req), NDTPA_UCAST_PROBES, &val,
+			 sizeof(val)))
+		return 0;
+	nl_attr_nest_end(&req.n, nest);
+
+	return netlink_talk(netlink_talk_filter, &req.n, &zns->netlink_cmd, zns,
+			    0);
+}
+
 static int netlink_neigh_update(int cmd, int ifindex, void *addr, char *lla,
 				int llalen, ns_id_t ns_id, uint8_t family,
 				bool permanent, uint8_t protocol)
@@ -3789,6 +3835,12 @@ netlink_put_neigh_update_msg(struct nl_batch *bth, struct zebra_dplane_ctx *ctx)
 				     false);
 }
 
+int kernel_configure_arp(struct interface *ifp, int family,
+			 ns_id_t ns_id)
+{
+	return netlink_configure_arp(ifp, family, ns_id);
+}
+
 /*
  * MPLS label forwarding table change via netlink interface, using dataplane
  * context information.
diff --git a/zebra/rt_socket.c b/zebra/rt_socket.c
index 006513ac9..cbbc9b28f 100644
--- a/zebra/rt_socket.c
+++ b/zebra/rt_socket.c
@@ -394,6 +394,11 @@ enum zebra_dplane_result kernel_mac_update_ctx(struct zebra_dplane_ctx *ctx)
 	return ZEBRA_DPLANE_REQUEST_SUCCESS;
 }
 
+int kernel_configure_arp(struct interface *ifp, int family, ns_id_t ns_id)
+{
+	return 0;
+}
+
 extern int kernel_interface_set_master(struct interface *master,
 				       struct interface *slave)
 {
diff --git a/zebra/zapi_msg.c b/zebra/zapi_msg.c
index 909b3b8ac..e880a6d7b 100644
--- a/zebra/zapi_msg.c
+++ b/zebra/zapi_msg.c
@@ -3279,6 +3279,28 @@ stream_failure:
 	return;
 }
 
+static inline void zebra_configure_arp(ZAPI_HANDLER_ARGS)
+{
+	struct stream *s;
+	int fam;
+	ifindex_t idx;
+	struct interface *ifp;
+	ns_id_t ns_id;
+
+	s = msg;
+	STREAM_GETC(s, fam);
+	if (fam != AF_INET && fam != AF_INET6)
+		return;
+	STREAM_GETL(s, idx);
+	ifp = if_lookup_by_index_per_ns(zvrf->zns, idx);
+	if (!ifp)
+		return;
+	ns_id = zvrf->zns->ns_id;
+	kernel_configure_arp(ifp, fam, ns_id);
+stream_failure:
+	return;
+}
+
 static inline void zebra_neigh_add(ZAPI_HANDLER_ARGS)
 {
 	struct stream *s;
@@ -3513,6 +3535,7 @@ void (*const zserv_handlers[])(ZAPI_HANDLER_ARGS) = {
 	[ZEBRA_NEIGH_DEL] = zebra_neigh_del,
 	[ZEBRA_NHRP_NEIGH_REGISTER] = zebra_neigh_register,
 	[ZEBRA_NHRP_NEIGH_UNREGISTER] = zebra_neigh_unregister,
+	[ZEBRA_CONFIGURE_ARP] = zebra_configure_arp,
 };
 
 /*