diff options
| author | Mark Stapp <mstapp@nvidia.com> | 2021-10-05 11:49:20 -0400 |
|---|---|---|
| committer | Mark Stapp <mstapp@nvidia.com> | 2021-10-08 09:11:51 -0400 |
| commit | bb2ca6927f98b53e9d860697ed82477eddbebe5c (patch) | |
| tree | 78287df4b0fc813637a98ce407b9932ff0781608 | |
| parent | 01236d7aa7dab0891fa25012f87bc1fe3bbcfe9b (diff) | |
bgpd: BGP-LU use implicit-null in some cases
In some cases where bgp is at the mpls edge, where it has a BGP-LU
peer downstream but an IP peer upstream, it can advertise the
IMPLICIT_NULL label instead of a per-prefix label.
Signed-off-by: Mark Stapp <mstapp@nvidia.com>
| -rw-r--r-- | bgpd/bgp_label.c | 4 | ||||
| -rw-r--r-- | bgpd/bgp_route.c | 28 |
2 files changed, 27 insertions, 5 deletions
diff --git a/bgpd/bgp_label.c b/bgpd/bgp_label.c index 3c8f2f3668..fa2a445165 100644 --- a/bgpd/bgp_label.c +++ b/bgpd/bgp_label.c @@ -244,6 +244,10 @@ void bgp_reg_dereg_for_label(struct bgp_dest *dest, struct bgp_path_info *pi, p = bgp_dest_get_prefix(dest); + if (BGP_DEBUG(labelpool, LABELPOOL)) + zlog_debug("%s: %pFX: %s ", __func__, p, + (reg ? "reg" : "dereg")); + if (reg) { assert(pi); /* diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c index fc97178450..f278cef77c 100644 --- a/bgpd/bgp_route.c +++ b/bgpd/bgp_route.c @@ -2712,6 +2712,28 @@ static void bgp_process_evpn_route_injection(struct bgp *bgp, afi_t afi, } /* + * Utility to determine whether a particular path_info should use + * the IMPLICIT_NULL label. This is pretty specialized: it's only called + * in a path where we basically _know_ this is a BGP-LU route. + */ +static bool bgp_lu_need_imp_null(const struct bgp_path_info *new_select) +{ + /* Certain types get imp null; so do paths where the nexthop is + * not labeled. + */ + if (new_select->sub_type == BGP_ROUTE_STATIC + || new_select->sub_type == BGP_ROUTE_AGGREGATE + || new_select->sub_type == BGP_ROUTE_REDISTRIBUTE) + return true; + else if (new_select->extra == NULL || + !bgp_is_valid_label(&new_select->extra->label[0])) + /* TODO -- should be configurable? */ + return true; + else + return false; +} + +/* * old_select = The old best path * new_select = the new best path * @@ -2802,11 +2824,7 @@ static void bgp_process_main_one(struct bgp *bgp, struct bgp_dest *dest, * implicit-null for local routes, aggregate * and redistributed routes */ - if (new_select->sub_type == BGP_ROUTE_STATIC - || new_select->sub_type - == BGP_ROUTE_AGGREGATE - || new_select->sub_type - == BGP_ROUTE_REDISTRIBUTE) { + if (bgp_lu_need_imp_null(new_select)) { if (CHECK_FLAG( dest->flags, BGP_NODE_REGISTERED_FOR_LABEL) |