lib, zebra: Check for not being a blackhole route

In zebra_interface_nhg_reinstall zebra is checking that the
nhg is a singleton and not a blackhole nhg.  This was originally
done with checking that the nexthop is a NEXTHOP_TYPE_IFINDEX,
NEXTHOP_TYPE_IPV4_IFINDEX and NEXTHOP_TYPE_IPV6_IFINDEX.  This
was excluding NEXTHOP_TYPE_IPV4 and NEXTHOP_TYPE_IPV6.  These
were both possible to be received and maintained from the upper
level protocol for when a route is being recursively resolved.
If we have gotten to this point in zebra_interface_nhg_reinstall
the nexthop group has already been installed at least once
and we *know* that it is actually a valid nexthop.  What the
test is really trying to do is ensure that we are not reinstalling
a blackhole nexthop group( Which is not possible to even be
here by the way, but safety first! ).  So let's change
to test for that instead.

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

1 files changed, 2 insertions, 6 deletions

diff --git a/lib/nexthop.c b/lib/nexthop.c
index 4ddb53cd96..243b52d554 100644
--- a/lib/nexthop.c
+++ b/lib/nexthop.c
@@ -1150,11 +1150,7 @@ static ssize_t printfrr_nh(struct fbuf *buf, struct printfrr_eargs *ea,
 	return -1;
 }
 
-bool nexthop_is_ifindex_type(const struct nexthop *nh)
+bool nexthop_is_blackhole(const struct nexthop *nh)
 {
-	if (nh->type == NEXTHOP_TYPE_IFINDEX ||
-	    nh->type == NEXTHOP_TYPE_IPV4_IFINDEX ||
-	    nh->type == NEXTHOP_TYPE_IPV6_IFINDEX)
-		return true;
-	return false;
+	return nh->type == NEXTHOP_TYPE_BLACKHOLE;
 }