diff options
Diffstat (limited to 'proto/bgp/attrs.c')
| -rw-r--r-- | proto/bgp/attrs.c | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c index d839ed0..7b49bdf 100644 --- a/proto/bgp/attrs.c +++ b/proto/bgp/attrs.c @@ -165,6 +165,22 @@ bgp_check_next_hop(struct bgp_proto *p UNUSED, byte *a, int len) #endif } +static void +bgp_format_next_hop(eattr *a, byte *buf, int buflen UNUSED) +{ + ip_addr *ipp = (ip_addr *) a->u.ptr->data; +#ifdef IPV6 + /* in IPv6, we might have two addresses in NEXT HOP */ + if ((a->u.ptr->length == NEXT_HOP_LENGTH) && ipa_nonzero(ipp[1])) + { + bsprintf(buf, "%I %I", ipp[0], ipp[1]); + return; + } +#endif + + bsprintf(buf, "%I", ipp[0]); +} + static int bgp_check_aggregator(struct bgp_proto *p, byte *a UNUSED, int len) { @@ -234,7 +250,7 @@ static struct attr_desc bgp_attr_table[] = { { "as_path", -1, BAF_TRANSITIVE, EAF_TYPE_AS_PATH, 1, /* BA_AS_PATH */ NULL, NULL }, /* is checked by validate_as_path() as a special case */ { "next_hop", 4, BAF_TRANSITIVE, EAF_TYPE_IP_ADDRESS, 1, /* BA_NEXT_HOP */ - bgp_check_next_hop, NULL }, + bgp_check_next_hop, bgp_format_next_hop }, { "med", 4, BAF_OPTIONAL, EAF_TYPE_INT, 1, /* BA_MULTI_EXIT_DISC */ NULL, NULL }, { "local_pref", 4, BAF_TRANSITIVE, EAF_TYPE_INT, 0, /* BA_LOCAL_PREF */ @@ -1044,7 +1060,6 @@ bgp_rte_better(rte *new, rte *old) return 0; /* RFC 4271 9.1.2.2. c) Compare MED's */ - if (bgp_get_neighbor(new) == bgp_get_neighbor(old)) { x = ea_find(new->attrs->eattrs, EA_CODE(EAP_BGP, BA_MULTI_EXIT_DISC)); @@ -1082,12 +1097,19 @@ bgp_rte_better(rte *new, rte *old) y = ea_find(old->attrs->eattrs, EA_CODE(EAP_BGP, BA_ORIGINATOR_ID)); n = x ? x->u.data : new_bgp->remote_id; o = y ? y->u.data : old_bgp->remote_id; + + /* RFC 5004 - prefer older routes */ + /* (if both are external and from different peer) */ + if ((new_bgp->cf->prefer_older || old_bgp->cf->prefer_older) && + !new_bgp->is_internal && n != o) + return 0; + + /* rest of RFC 4271 9.1.2.2. f) */ if (n < o) return 1; if (n > o) return 0; - /* RFC 4271 9.1.2.2. g) Compare peer IP adresses */ return (ipa_compare(new_bgp->cf->remote_ip, old_bgp->cf->remote_ip) < 0); } |