*: convert zclient callbacks to table

This removes a giant `switch { }` block from lib/zclient.c and
harmonizes all zclient callback function types to be the same (some had
a subset of the args, some had a void return, now they all have
ZAPI_CALLBACK_ARGS and int return.)

Apart from getting rid of the giant switch, this is a minor security
benefit since the function pointers are now in a `const` array, so they
can't be overwritten by e.g. heap overflows for code execution anymore.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

1 files changed, 7 insertions, 4 deletions

diff --git a/bgpd/rfapi/vnc_zebra.c b/bgpd/rfapi/vnc_zebra.c
index ba849e4e0b..672a0e9780 100644
--- a/bgpd/rfapi/vnc_zebra.c
+++ b/bgpd/rfapi/vnc_zebra.c
@@ -895,6 +895,11 @@ int vnc_redistribute_unset(struct bgp *bgp, afi_t afi, int type)
 
 extern struct zebra_privs_t bgpd_privs;
 
+static zclient_handler *const vnc_handlers[] = {
+	[ZEBRA_REDISTRIBUTE_ROUTE_ADD] = vnc_zebra_read_route,
+	[ZEBRA_REDISTRIBUTE_ROUTE_DEL] = vnc_zebra_read_route,
+};
+
 /*
  * Modeled after bgp_zebra.c'bgp_zebra_init()
  * Charriere asks, "Is it possible to carry two?"
@@ -902,11 +907,9 @@ extern struct zebra_privs_t bgpd_privs;
 void vnc_zebra_init(struct thread_master *master)
 {
 	/* Set default values. */
-	zclient_vnc = zclient_new(master, &zclient_options_default);
+	zclient_vnc = zclient_new(master, &zclient_options_default,
+				  vnc_handlers, array_size(vnc_handlers));
 	zclient_init(zclient_vnc, ZEBRA_ROUTE_VNC, 0, &bgpd_privs);
-
-	zclient_vnc->redistribute_route_add = vnc_zebra_read_route;
-	zclient_vnc->redistribute_route_del = vnc_zebra_read_route;
 }
 
 void vnc_zebra_destroy(void)