diff options
Diffstat (limited to 'bgpd/bgp_route.c')
| -rw-r--r-- | bgpd/bgp_route.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c index 1d1f3d9b26..6735c1a952 100644 --- a/bgpd/bgp_route.c +++ b/bgpd/bgp_route.c @@ -3505,6 +3505,34 @@ bool bgp_update_martian_nexthop(struct bgp *bgp, afi_t afi, safi_t safi, return ret; } +static void bgp_attr_add_no_advertise_community(struct attr *attr) +{ + struct community *old; + struct community *new; + struct community *merge; + struct community *noadv; + + old = attr->community; + noadv = community_str2com("no-advertise"); + + if (old) { + merge = community_merge(community_dup(old), noadv); + + if (!old->refcnt) + community_free(&old); + + new = community_uniq_sort(merge); + community_free(&merge); + } else { + new = community_dup(noadv); + } + + community_free(&noadv); + + attr->community = new; + attr->flag |= ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES); +} + int bgp_update(struct peer *peer, const struct prefix *p, uint32_t addpath_id, struct attr *attr, afi_t afi, safi_t safi, int type, int sub_type, struct prefix_rd *prd, mpls_label_t *label, @@ -3697,6 +3725,20 @@ int bgp_update(struct peer *peer, const struct prefix *p, uint32_t addpath_id, if (peer->sort == BGP_PEER_EBGP) { + /* rfc7999: + * A BGP speaker receiving an announcement tagged with the + * BLACKHOLE community SHOULD add the NO_ADVERTISE or + * NO_EXPORT community as defined in RFC1997, or a + * similar community, to prevent propagation of the + * prefix outside the local AS. The community to prevent + * propagation SHOULD be chosen according to the operator's + * routing policy. + */ + if (new_attr.community + && community_include(new_attr.community, + COMMUNITY_BLACKHOLE)) + bgp_attr_add_no_advertise_community(&new_attr); + /* If we receive the graceful-shutdown community from an eBGP * peer we must lower local-preference */ if (new_attr.community |