bgpd: Add code to track the addition/removal of mac addresses

When a mac address is added/changed/deleted track it.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

bgpd/bgp_mac.c

@@ -32,6 +32,7 @@
 #include "bgpd/bgp_debug.h"
 
 DEFINE_MTYPE_STATIC(BGPD, BSM, "Mac Hash Entry");
+DEFINE_MTYPE_STATIC(BGPD, BSM_STRING, "Mac Hash Entry Interface String");
 
 struct bgp_self_mac {
 	struct ethaddr macaddr;
@@ -76,6 +77,137 @@ void bgp_mac_finish(void)
 	hash_free(bm->self_mac_hash);
 }
 
+static void bgp_mac_hash_interface_string_del(void *val)
+{
+	char *data = val;
+
+	XFREE(MTYPE_BSM_STRING, data);
+}
+
+static void *bgp_mac_hash_alloc(void *p)
+{
+	const struct bgp_self_mac *orig = p;
+	struct bgp_self_mac *bsm;
+
+	bsm = XCALLOC(MTYPE_BSM, sizeof(struct bgp_self_mac));
+	memcpy(&bsm->macaddr, &orig->macaddr, ETH_ALEN);
+
+	bsm->ifp_list = list_new();
+	bsm->ifp_list->del = bgp_mac_hash_interface_string_del;
+
+	return bsm;
+}
+
+struct bgp_mac_find_internal {
+	struct bgp_self_mac *bsm;
+	const char *ifname;
+};
+
+static void bgp_mac_find_ifp_internal(struct hash_backet *backet, void *arg)
+{
+	struct bgp_mac_find_internal *bmfi = arg;
+	struct bgp_self_mac *bsm = backet->data;
+	struct listnode *node;
+	char *name;
+
+	for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name)) {
+		if (strcmp(name, bmfi->ifname) == 0) {
+			bmfi->bsm = bsm;
+			return;
+		}
+	}
+}
+
+static struct bgp_self_mac *bgp_mac_find_interface_name(const char *ifname)
+{
+	struct bgp_mac_find_internal bmfi;
+
+	bmfi.bsm = NULL;
+	bmfi.ifname = ifname;
+	hash_iterate(bm->self_mac_hash, bgp_mac_find_ifp_internal, &bmfi);
+
+	return bmfi.bsm;
+}
+
+static void bgp_mac_remove_ifp_internal(struct bgp_self_mac *bsm, char *ifname)
+{
+	struct listnode *node;
+	char *name;
+
+	for (ALL_LIST_ELEMENTS_RO(bsm->ifp_list, node, name)) {
+		if (strcmp(name, ifname) == 0)
+			break;
+	}
+
+	if (node) {
+		list_delete_node(bsm->ifp_list, node);
+		XFREE(MTYPE_BSM_STRING, name);
+	}
+
+	if (bsm->ifp_list->count == 0) {
+		hash_release(bm->self_mac_hash, bsm);
+		list_delete(&bsm->ifp_list);
+		XFREE(MTYPE_BSM, bsm);
+
+		/* Code to rescan tables */
+	}
+}
+
+void bgp_mac_add_mac_entry(struct interface *ifp)
+{
+	struct bgp_self_mac lookup;
+	struct bgp_self_mac *bsm;
+	struct bgp_self_mac *old_bsm;
+	char *ifname;
+
+	memcpy(&lookup.macaddr, &ifp->hw_addr, ETH_ALEN);
+	bsm = hash_get(bm->self_mac_hash, &lookup, bgp_mac_hash_alloc);
+
+	/*
+	 * Does this happen to be a move
+	 */
+	old_bsm = bgp_mac_find_interface_name(ifp->name);
+	ifname = XSTRDUP(MTYPE_BSM_STRING, ifp->name);
+
+	if (bsm->ifp_list->count == 0) {
+
+		listnode_add(bsm->ifp_list, ifname);
+		if (old_bsm)
+			bgp_mac_remove_ifp_internal(old_bsm, ifname);
+	} else {
+		/*
+		 * If old mac address is the same as the new,
+		 * then there is nothing to do here
+		 */
+		if (old_bsm == bsm)
+			return;
+
+		if (old_bsm)
+			bgp_mac_remove_ifp_internal(old_bsm, ifp->name);
+
+		listnode_add(bsm->ifp_list, ifname);
+	}
+
+	/* Code to rescan */
+}
+
+void bgp_mac_del_mac_entry(struct interface *ifp)
+{
+	struct bgp_self_mac lookup;
+	struct bgp_self_mac *bsm;
+
+	memcpy(&lookup.macaddr, &ifp->hw_addr, ETH_ALEN);
+	bsm = hash_lookup(bm->self_mac_hash, &lookup);
+	if (!bsm)
+		return;
+
+	/*
+	 * Write code to allow old mac address to no-longer
+	 * win if we happen to have received it from a peer.
+	 */
+	bgp_mac_remove_ifp_internal(bsm, ifp->name);
+}
+
 static void bgp_mac_show_mac_entry(struct hash_backet *backet, void *arg)
 {
 	struct vty *vty = arg;

bgpd/bgp_mac.h

@@ -23,5 +23,13 @@
 void bgp_mac_init(void);
 void bgp_mac_finish(void);
 
+/*
+ * Functions to add/delete the mac entry from the appropriate
+ * bgp hash's.  Additionally to do some additional processing
+ * to allow the win/loss to be processed.
+ */
+void bgp_mac_add_mac_entry(struct interface *ifp);
+void bgp_mac_del_mac_entry(struct interface *ifp);
+
 void bgp_mac_dump_table(struct vty *vty);
 #endif

bgpd/bgp_zebra.c

@@ -59,6 +59,7 @@
 #include "bgpd/bgp_labelpool.h"
 #include "bgpd/bgp_pbr.h"
 #include "bgpd/bgp_evpn_private.h"
+#include "bgpd/bgp_mac.h"
 
 /* All information about zebra. */
 struct zclient *zclient = NULL;
@@ -221,6 +222,8 @@ static int bgp_interface_add(int command, struct zclient *zclient,
 	if (!bgp)
 		return 0;
 
+	bgp_mac_add_mac_entry(ifp);
+
 	bgp_update_interface_nbrs(bgp, ifp, ifp);
 	return 0;
 }
@@ -245,6 +248,8 @@ static int bgp_interface_delete(int command, struct zclient *zclient,
 	if (bgp)
 		bgp_update_interface_nbrs(bgp, ifp, NULL);
 
+	bgp_mac_del_mac_entry(ifp);
+
 	if_set_index(ifp, IFINDEX_INTERNAL);
 	return 0;
 }
@@ -267,6 +272,8 @@ static int bgp_interface_up(int command, struct zclient *zclient,
 	if (!ifp)
 		return 0;
 
+	bgp_mac_add_mac_entry(ifp);
+
 	if (BGP_DEBUG(zebra, ZEBRA))
 		zlog_debug("Rx Intf up VRF %u IF %s", vrf_id, ifp->name);
 
@@ -300,6 +307,8 @@ static int bgp_interface_down(int command, struct zclient *zclient,
 	if (!ifp)
 		return 0;
 
+	bgp_mac_del_mac_entry(ifp);
+
 	if (BGP_DEBUG(zebra, ZEBRA))
 		zlog_debug("Rx Intf down VRF %u IF %s", vrf_id, ifp->name);