diff options
Diffstat (limited to 'proto/bgp/attrs.c')
| -rw-r--r-- | proto/bgp/attrs.c | 37 |
1 files changed, 24 insertions, 13 deletions
diff --git a/proto/bgp/attrs.c b/proto/bgp/attrs.c index b28cbd55..1f927cbd 100644 --- a/proto/bgp/attrs.c +++ b/proto/bgp/attrs.c @@ -45,9 +45,9 @@ * * export - Hook that validates and normalizes attribute during export phase. * Receives eattr, may modify it (e.g., sort community lists for canonical - * representation), UNSET() it (e.g., skip empty lists), or WITHDRAW() it if - * necessary. May assume that eattr has value valid w.r.t. its type, but may be - * invalid w.r.t. BGP constraints. Optional. + * representation), UNSET() it (e.g., skip empty lists), or REJECT() the route + * if necessary. May assume that eattr has value valid w.r.t. its type, but may + * be invalid w.r.t. BGP constraints. Optional. * * encode - Hook that converts internal representation to external one during * packet writing. Receives eattr and puts it in the buffer (including attribute @@ -108,6 +108,9 @@ bgp_set_attr(ea_list **attrs, struct linpool *pool, uint code, uint flags, uintp #define UNSET(a) \ ({ a->type = EAF_TYPE_UNDEF; return; }) +#define REJECT(msg, args...) \ + ({ log(L_ERR "%s: " msg, s->proto->p.name, ## args); s->err_reject = 1; return; }) + #define NEW_BGP "Discarding %s attribute received from AS4-aware neighbor" #define BAD_EBGP "Discarding %s attribute received from EBGP neighbor" #define BAD_LENGTH "Malformed %s attribute - invalid length (%u)" @@ -380,7 +383,7 @@ static void bgp_export_origin(struct bgp_export_state *s, eattr *a) { if (a->u.data > 2) - WITHDRAW(BAD_VALUE, "ORIGIN", a->u.data); + REJECT(BAD_VALUE, "ORIGIN", a->u.data); } static void @@ -902,20 +905,20 @@ bgp_export_mpls_label_stack(struct bgp_export_state *s, eattr *a) /* Perhaps we should just ignore it? */ if (!s->mpls) - WITHDRAW("Unexpected MPLS stack"); + REJECT("Unexpected MPLS stack"); /* Empty MPLS stack is not allowed */ if (!lnum) - WITHDRAW("Malformed MPLS stack - empty"); + REJECT("Malformed MPLS stack - empty"); /* This is ugly, but we must ensure that labels fit into NLRI field */ if ((24*lnum + (net_is_vpn(n) ? 64 : 0) + net_pxlen(n)) > 255) - WITHDRAW("Malformed MPLS stack - too many labels (%u)", lnum); + REJECT("Malformed MPLS stack - too many labels (%u)", lnum); for (uint i = 0; i < lnum; i++) { if (labels[i] > 0xfffff) - WITHDRAW("Malformed MPLS stack - invalid label (%u)", labels[i]); + REJECT("Malformed MPLS stack - invalid label (%u)", labels[i]); /* TODO: Check for special-purpose label values? */ } @@ -1196,7 +1199,7 @@ bgp_export_attrs(struct bgp_export_state *s, ea_list *attrs) for (i = 0; i < count; i++) bgp_export_attr(s, &new->attrs[i], new); - if (s->err_withdraw) + if (s->err_reject) return NULL; return new; @@ -1394,19 +1397,19 @@ bgp_decode_attrs(struct bgp_parse_state *s, byte *data, uint len) /* Reject routes with our ASN in AS_PATH attribute */ if (bgp_as_path_loopy(p, attrs, p->local_as)) - goto withdraw; + goto loop; /* Reject routes with our Confederation ID in AS_PATH attribute; RFC 5065 4.0 */ if ((p->public_as != p->local_as) && bgp_as_path_loopy(p, attrs, p->public_as)) - goto withdraw; + goto loop; /* Reject routes with our Router ID in ORIGINATOR_ID attribute; RFC 4456 8 */ if (p->is_internal && bgp_originator_id_loopy(p, attrs)) - goto withdraw; + goto loop; /* Reject routes with our Cluster ID in CLUSTER_LIST attribute; RFC 4456 8 */ if (p->rr_client && bgp_cluster_list_loopy(p, attrs)) - goto withdraw; + goto loop; /* If there is no local preference, define one */ if (!BIT32_TEST(s->attrs_seen, BA_LOCAL_PREF)) @@ -1427,6 +1430,10 @@ withdraw: s->err_withdraw = 1; return NULL; + +loop: + /* Loops are handled as withdraws, but ignored silently. Do not set err_withdraw. */ + return NULL; } void @@ -1849,6 +1856,10 @@ bgp_rt_notify(struct proto *P, struct channel *C, net *n, rte *new, rte *old) { struct ea_list *attrs = bgp_update_attrs(p, c, new, new->attrs->eattrs, bgp_linpool2); + /* Error during attribute processing */ + if (!attrs) + log(L_ERR "%s: Invalid route %N withdrawn", p->p.name, n->n.addr); + /* If attributes are invalid, we fail back to withdraw */ buck = attrs ? bgp_get_bucket(c, attrs) : bgp_get_withdraw_bucket(c); path = new->attrs->src->global_id; |