*: When matching against a nexthop send and process what it matched against

Currently the nexthop tracking code is only sending to the requestor
what it was requested to match against.  When the nexthop tracking
code was simplified to not need an import check and a nexthop check
in b8210849b8ac1abe2d5d9a5ab2459abfde65efa5 for bgpd.  It was not
noticed that a longer prefix could match but it would be seen
as a match because FRR was not sending up both the resolved
route prefix and the route FRR was asked to match against.

This code change causes the nexthop tracking code to pass
back up the matched requested route (so that the calling
protocol can figure out which one it is being told about )
as well as the actual prefix that was matched to.

Fixes: #10766
Signed-off-by: Donald Sharp <sharpd@nvidia.com>

1 files changed, 5 insertions, 4 deletions

diff --git a/sharpd/sharp_zebra.c b/sharpd/sharp_zebra.c
index 313febd9bb..5304b17f06 100644
--- a/sharpd/sharp_zebra.c
+++ b/sharpd/sharp_zebra.c
@@ -680,16 +680,17 @@ static int sharp_nexthop_update(ZAPI_CALLBACK_ARGS)
 {
 	struct sharp_nh_tracker *nht;
 	struct zapi_route nhr;
+	struct prefix matched;
 
-	if (!zapi_nexthop_update_decode(zclient->ibuf, &nhr)) {
+	if (!zapi_nexthop_update_decode(zclient->ibuf, &matched, &nhr)) {
 		zlog_err("%s: Decode of update failed", __func__);
 		return 0;
 	}
 
-	zlog_debug("Received update for %pFX metric: %u", &nhr.prefix,
-		   nhr.metric);
+	zlog_debug("Received update for %pFX actual match: %pFX metric: %u",
+		   &matched, &nhr.prefix, nhr.metric);
 
-	nht = sharp_nh_tracker_get(&nhr.prefix);
+	nht = sharp_nh_tracker_get(&matched);
 	nht->nhop_num = nhr.nexthop_num;
 	nht->updates++;