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authorOndrej Zajicek (work) <santiago@crfreenet.org>2017-02-07 15:55:51 +0100
committerOndrej Zajicek (work) <santiago@crfreenet.org>2017-02-07 15:55:51 +0100
commit82f42ea09176afdb67ab119258d714e8c8e54d12 (patch)
treea9765b5ad88f08a2edb8fe3584cf7430b4c85904 /proto/bgp/attrs.c
parentd8022d26fc64121c3416abfdb4c38fcbaf81c12e (diff)
BGP: Minor cleanups
Diffstat (limited to 'proto/bgp/attrs.c')
-rw-r--r--proto/bgp/attrs.c47
1 files changed, 27 insertions, 20 deletions
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c
index c557403b..d5bf2add 100644
--- a/proto/bgp/attrs.c
+++ b/proto/bgp/attrs.c
@@ -1325,29 +1325,23 @@ bgp_import_control(struct proto *P, rte **new, ea_list **attrs UNUSED, struct li
static adata null_adata; /* adata of length 0 */
-static inline void
-bgp_cluster_list_prepend(ea_list **attrs, struct linpool *pool, u32 id)
-{
- eattr *a = bgp_find_attr(*attrs, BA_CLUSTER_LIST);
- adata *d = int_set_add(pool, a ? a->u.ptr : NULL, id);
- bgp_set_attr_ptr(attrs, pool, BA_CLUSTER_LIST, 0, d);
-}
-
static ea_list *
-bgp_update_attrs(struct bgp_proto *p, struct bgp_channel *c, rte *e, ea_list *attrs, struct linpool *pool)
+bgp_update_attrs(struct bgp_proto *p, struct bgp_channel *c, rte *e, ea_list *attrs0, struct linpool *pool)
{
struct proto *SRC = e->attrs->src->proto;
struct bgp_proto *src = (SRC->proto == &proto_bgp) ? (void *) SRC : NULL;
struct bgp_export_state s = { .proto = p, .channel =c, .pool = pool, .src = src, .route = e };
+ ea_list *attrs = attrs0;
eattr *a;
+ adata *ad;
/* ORIGIN attribute - mandatory, attach if missing */
- if (! bgp_find_attr(attrs, BA_ORIGIN))
+ if (! bgp_find_attr(attrs0, BA_ORIGIN))
bgp_set_attr_u32(&attrs, pool, BA_ORIGIN, 0, src ? ORIGIN_INCOMPLETE : ORIGIN_IGP);
- /* AS_PATH attribute */
- a = bgp_find_attr(attrs, BA_AS_PATH);
- adata *ad = a ? a->u.ptr : &null_adata;
+ /* AS_PATH attribute - mandatory */
+ a = bgp_find_attr(attrs0, BA_AS_PATH);
+ ad = a ? a->u.ptr : &null_adata;
/* AS_PATH attribute - strip AS_CONFED* segments outside confederation */
if ((!p->cf->confederation || !p->is_interior) && as_path_contains_confed(ad))
@@ -1374,33 +1368,40 @@ bgp_update_attrs(struct bgp_proto *p, struct bgp_channel *c, rte *e, ea_list *at
bgp_set_attr_ptr(&attrs, pool, BA_AS_PATH, 0, ad);
/* MULTI_EXIT_DESC attribute - accept only if set in export filter */
- a = bgp_find_attr(attrs, BA_MULTI_EXIT_DISC);
+ a = bgp_find_attr(attrs0, BA_MULTI_EXIT_DISC);
if (a && !(a->type & EAF_FRESH))
bgp_unset_attr(&attrs, pool, BA_MULTI_EXIT_DISC);
}
/* NEXT_HOP attribute - delegated to AF-specific hook */
- a = bgp_find_attr(attrs, BA_NEXT_HOP);
+ a = bgp_find_attr(attrs0, BA_NEXT_HOP);
bgp_update_next_hop(&s, a, &attrs);
/* LOCAL_PREF attribute - required for IBGP, attach if missing */
- if (p->is_interior && ! bgp_find_attr(attrs, BA_LOCAL_PREF))
+ if (p->is_interior && ! bgp_find_attr(attrs0, BA_LOCAL_PREF))
bgp_set_attr_u32(&attrs, pool, BA_LOCAL_PREF, 0, p->cf->default_local_pref);
/* IBGP route reflection, RFC 4456 */
if (src && src->is_internal && p->is_internal && (src->local_as == p->local_as))
{
/* ORIGINATOR_ID attribute - attach if not already set */
- if (! bgp_find_attr(attrs, BA_ORIGINATOR_ID))
+ if (! bgp_find_attr(attrs0, BA_ORIGINATOR_ID))
bgp_set_attr_u32(&attrs, pool, BA_ORIGINATOR_ID, 0, src->remote_id);
/* CLUSTER_LIST attribute - prepend cluster ID */
+ a = bgp_find_attr(attrs0, BA_CLUSTER_LIST);
+ ad = a ? a->u.ptr : NULL;
+
+ /* Prepend src cluster ID */
if (src->rr_cluster_id)
- bgp_cluster_list_prepend(&attrs, pool, src->rr_cluster_id);
+ ad = int_set_add(pool, ad, src->rr_cluster_id);
- /* Handle different src and dst cluster ID - prepend both ones */
+ /* Prepend dst cluster ID if src and dst clusters are different */
if (p->rr_cluster_id && (src->rr_cluster_id != p->rr_cluster_id))
- bgp_cluster_list_prepend(&attrs, pool, p->rr_cluster_id);
+ ad = int_set_add(pool, ad, p->rr_cluster_id);
+
+ /* Should be at least one prepended cluster ID */
+ bgp_set_attr_ptr(&attrs, pool, BA_CLUSTER_LIST, 0, ad);
}
/* AS4_* transition attributes, RFC 6793 4.2.2 */
@@ -1421,6 +1422,12 @@ bgp_update_attrs(struct bgp_proto *p, struct bgp_channel *c, rte *e, ea_list *at
}
}
+ /*
+ * Presence of mandatory attributes ORIGIN and AS_PATH is ensured by above
+ * conditions. Presence and validity of quasi-mandatory NEXT_HOP attribute
+ * should be checked in AF-specific hooks.
+ */
+
/* Apply per-attribute export hooks for validatation and normalization */
return bgp_export_attrs(&s, attrs);
}