BGP: Log route updates that were changed to withdraws

Typical BGP error handling is treat-as-withdraw, where an invalid route
is replaced with a withdraw. Log route network when it happens.
This commit is contained in:
Ondrej Zajicek (work) 2022-01-24 03:44:21 +01:00
parent a9646efd40
commit 9dbb7eb6eb
3 changed files with 12 additions and 1 deletions

View file

@ -1845,6 +1845,10 @@ 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); 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log(L_ERR "%s: Invalid route %N withdrawn", p-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 */ /* If attributes are invalid, we fail back to withdraw */
buck = attrs ? bgp_get_bucket(c, attrs) : bgp_get_withdraw_bucket(c); buck = attrs ? bgp_get_bucket(c, attrs) : bgp_get_withdraw_bucket(c);
path = new->attrs->src->global_id; path = new->attrs->src->global_id;

View file

@ -423,6 +423,7 @@ struct bgp_parse_state {
int as4_session; int as4_session;
int add_path; int add_path;
int mpls; int mpls;
int reach_nlri_step;
u32 attrs_seen[256/32]; u32 attrs_seen[256/32];

View file

@ -1335,7 +1335,7 @@ bgp_update_next_hop_none(struct bgp_export_state *s, eattr *a, ea_list **to)
*/ */
static void static void
bgp_rte_update(struct bgp_parse_state *s, net_addr *n, u32 path_id, rta *a0) bgp_rte_update(struct bgp_parse_state *s, const net_addr *n, u32 path_id, rta *a0)
{ {
if (path_id != s->last_id) if (path_id != s->last_id)
{ {
@ -1348,6 +1348,10 @@ bgp_rte_update(struct bgp_parse_state *s, net_addr *n, u32 path_id, rta *a0)
if (!a0) if (!a0)
{ {
/* Route update was changed to withdraw */
if (s->err_withdraw && s->reach_nlri_step)
REPORT("Invalid route %N withdrawn", n);
/* Route withdraw */ /* Route withdraw */
rte_update3(&s->channel->c, n, NULL, s->last_src); rte_update3(&s->channel->c, n, NULL, s->last_src);
return; return;
@ -2543,6 +2547,8 @@ bgp_rx_update(struct bgp_conn *conn, byte *pkt, uint len)
if (s.mp_unreach_len) if (s.mp_unreach_len)
bgp_decode_nlri(&s, s.mp_unreach_af, s.mp_unreach_nlri, s.mp_unreach_len, NULL, NULL, 0); bgp_decode_nlri(&s, s.mp_unreach_af, s.mp_unreach_nlri, s.mp_unreach_len, NULL, NULL, 0);
s.reach_nlri_step = 1;
if (s.ip_reach_len) if (s.ip_reach_len)
bgp_decode_nlri(&s, BGP_AF_IPV4, s.ip_reach_nlri, s.ip_reach_len, bgp_decode_nlri(&s, BGP_AF_IPV4, s.ip_reach_nlri, s.ip_reach_len,
ea, s.ip_next_hop_data, s.ip_next_hop_len); ea, s.ip_next_hop_data, s.ip_next_hop_len);