BGP: Some fixes related to VRF and MPLS interactions

- When next hop is reset to local IP, we should remove BGP label stack,
   as it is related to original next hop

 - BGP next hop or immediate next hop from one VRF should not be passed
   to another VRF, as they are different IP namespaces
This commit is contained in:
Ondrej Zajicek 2022-09-27 16:13:27 +02:00
parent 54430df953
commit da0b589e7b

View file

@ -1112,6 +1112,10 @@ bgp_use_next_hop(struct bgp_export_state *s, eattr *a)
if ((ipa_is_ip4(*nh) != bgp_channel_is_ipv4(c)) && !c->ext_next_hop) if ((ipa_is_ip4(*nh) != bgp_channel_is_ipv4(c)) && !c->ext_next_hop)
return 0; return 0;
/* Do not pass NEXT_HOP between different VRFs */
if (p->p.vrf_set && s->src && s->src->p.vrf_set && (p->p.vrf != s->src->p.vrf))
return 0;
/* Keep it when exported to internal peers */ /* Keep it when exported to internal peers */
if (p->is_interior && ipa_nonzero(*nh)) if (p->is_interior && ipa_nonzero(*nh))
return 1; return 1;
@ -1141,6 +1145,10 @@ bgp_use_gateway(struct bgp_export_state *s)
if ((ipa_is_ip4(ra->nh.gw) != bgp_channel_is_ipv4(c)) && !c->ext_next_hop) if ((ipa_is_ip4(ra->nh.gw) != bgp_channel_is_ipv4(c)) && !c->ext_next_hop)
return 0; return 0;
/* Do not use gateway from different VRF */
if (p->p.vrf_set && ra->nh.iface && (p->p.vrf != ra->nh.iface->master))
return 0;
/* Use it when exported to internal peers */ /* Use it when exported to internal peers */
if (p->is_interior) if (p->is_interior)
return 1; return 1;
@ -1167,6 +1175,8 @@ bgp_update_next_hop_ip(struct bgp_export_state *s, eattr *a, ea_list **to)
uint lnum = ra->nh.labels ? ra->nh.labels : 1; uint lnum = ra->nh.labels ? ra->nh.labels : 1;
bgp_set_attr_data(to, s->pool, BA_MPLS_LABEL_STACK, 0, labels, lnum * 4); bgp_set_attr_data(to, s->pool, BA_MPLS_LABEL_STACK, 0, labels, lnum * 4);
} }
else
bgp_unset_attr(to, s->pool, BA_MPLS_LABEL_STACK);
} }
else else
{ {
@ -1180,6 +1190,8 @@ bgp_update_next_hop_ip(struct bgp_export_state *s, eattr *a, ea_list **to)
u32 implicit_null = BGP_MPLS_NULL; u32 implicit_null = BGP_MPLS_NULL;
bgp_set_attr_data(to, s->pool, BA_MPLS_LABEL_STACK, 0, &implicit_null, 4); bgp_set_attr_data(to, s->pool, BA_MPLS_LABEL_STACK, 0, &implicit_null, 4);
} }
else
bgp_unset_attr(to, s->pool, BA_MPLS_LABEL_STACK);
} }
} }