return new;
}
+void bgp_mplsvpn_path_nh_label_unlink(struct bgp_path_info *pi)
+{
+ struct bgp_label_per_nexthop_cache *blnc;
+
+ if (!pi)
+ return;
+
+ blnc = pi->label_nexthop_cache;
+
+ if (!blnc)
+ return;
+
+ LIST_REMOVE(pi, label_nh_thread);
+ pi->label_nexthop_cache->path_count--;
+ pi->label_nexthop_cache = NULL;
+
+ if (LIST_EMPTY(&(blnc->paths)))
+ bgp_label_per_nexthop_free(blnc);
+}
+
+/* Called upon reception of a ZAPI Message from zebra, about
+ * a new available label.
+ */
+static int bgp_mplsvpn_get_label_per_nexthop_cb(mpls_label_t label,
+ void *context, bool allocated)
+{
+ struct bgp_label_per_nexthop_cache *blnc = context;
+ mpls_label_t old_label;
+ int debug = BGP_DEBUG(vpn, VPN_LEAK_LABEL);
+ struct bgp_path_info *pi;
+ struct bgp_table *table;
+
+ old_label = blnc->label;
+
+ if (debug)
+ zlog_debug("%s: label=%u, allocated=%d, nexthop=%pFX", __func__,
+ label, allocated, &blnc->nexthop);
+ if (allocated)
+ /* update the entry with the new label */
+ blnc->label = label;
+ else
+ /*
+ * previously-allocated label is now invalid
+ * eg: zebra deallocated the labels and notifies it
+ */
+ blnc->label = MPLS_INVALID_LABEL;
+
+ if (old_label == blnc->label)
+ return 0; /* no change */
+
+ /* update paths */
+ if (blnc->label != MPLS_INVALID_LABEL)
+ bgp_zebra_send_nexthop_label(ZEBRA_MPLS_LABELS_ADD, blnc->label,
+ ZEBRA_LSP_BGP, &blnc->nexthop);
+
+ LIST_FOREACH (pi, &(blnc->paths), label_nh_thread) {
+ if (!pi->net)
+ continue;
+ table = bgp_dest_table(pi->net);
+ if (!table)
+ continue;
+ vpn_leak_from_vrf_update(blnc->to_bgp, table->bgp, pi);
+ }
+
+ return 0;
+}
+
+/* Get a per label nexthop value:
+ * - Find and return a per label nexthop from the cache
+ * - else allocate a new per label nexthop cache entry and request a
+ * label to zebra. Return MPLS_INVALID_LABEL
+ */
+static mpls_label_t _vpn_leak_from_vrf_get_per_nexthop_label(
+ struct bgp_path_info *pi, struct bgp *to_bgp, struct bgp *from_bgp,
+ afi_t afi, safi_t safi)
+{
+ struct bgp_nexthop_cache *bnc = pi->nexthop;
+ struct bgp_label_per_nexthop_cache *blnc;
+ struct bgp_label_per_nexthop_cache_head *tree;
+ struct prefix *nh_pfx = NULL;
+ struct prefix nh_gate = {0};
+
+ /* extract the nexthop from the BNC nexthop cache */
+ switch (bnc->nexthop->type) {
+ case NEXTHOP_TYPE_IPV4:
+ case NEXTHOP_TYPE_IPV4_IFINDEX:
+ /* the nexthop is recursive */
+ nh_gate.family = AF_INET;
+ nh_gate.prefixlen = IPV4_MAX_BITLEN;
+ IPV4_ADDR_COPY(&nh_gate.u.prefix4, &bnc->nexthop->gate.ipv4);
+ nh_pfx = &nh_gate;
+ break;
+ case NEXTHOP_TYPE_IPV6:
+ case NEXTHOP_TYPE_IPV6_IFINDEX:
+ /* the nexthop is recursive */
+ nh_gate.family = AF_INET6;
+ nh_gate.prefixlen = IPV6_MAX_BITLEN;
+ IPV6_ADDR_COPY(&nh_gate.u.prefix6, &bnc->nexthop->gate.ipv6);
+ nh_pfx = &nh_gate;
+ break;
+ case NEXTHOP_TYPE_IFINDEX:
+ /* the nexthop is direcly connected */
+ nh_pfx = &bnc->prefix;
+ break;
+ case NEXTHOP_TYPE_BLACKHOLE:
+ assert(!"Blackhole nexthop. Already checked by the caller.");
+ }
+
+ /* find or allocate a nexthop label cache entry */
+ tree = &from_bgp->mpls_labels_per_nexthop[family2afi(nh_pfx->family)];
+ blnc = bgp_label_per_nexthop_find(tree, nh_pfx);
+ if (!blnc) {
+ blnc = bgp_label_per_nexthop_new(tree, nh_pfx);
+ blnc->to_bgp = to_bgp;
+ /* request a label to zebra for this nexthop
+ * the response from zebra will trigger the callback
+ */
+ bgp_lp_get(LP_TYPE_NEXTHOP, blnc,
+ bgp_mplsvpn_get_label_per_nexthop_cb);
+ }
+
+ if (pi->label_nexthop_cache == blnc)
+ /* no change */
+ return blnc->label;
+
+ /* Unlink from any existing nexthop cache. Free the entry if unused.
+ */
+ bgp_mplsvpn_path_nh_label_unlink(pi);
+ if (blnc) {
+ /* updates NHT pi list reference */
+ LIST_INSERT_HEAD(&(blnc->paths), pi, label_nh_thread);
+ pi->label_nexthop_cache = blnc;
+ pi->label_nexthop_cache->path_count++;
+ }
+ return blnc->label;
+}
+
+/* Filter out all the cases where a per nexthop label is not possible:
+ * - return an invalid label when the nexthop is invalid
+ * - return the per VRF label when the per nexthop label is not supported
+ * Otherwise, find or request a per label nexthop.
+ */
+static mpls_label_t vpn_leak_from_vrf_get_per_nexthop_label(
+ afi_t afi, safi_t safi, struct bgp_path_info *pi, struct bgp *from_bgp,
+ struct bgp *to_bgp)
+{
+ struct bgp_path_info *bpi_ultimate = bgp_get_imported_bpi_ultimate(pi);
+ struct bgp *bgp_nexthop = NULL;
+ bool nh_valid;
+ afi_t nh_afi;
+ bool is_bgp_static_route;
+
+ is_bgp_static_route = bpi_ultimate->sub_type == BGP_ROUTE_STATIC &&
+ bpi_ultimate->type == ZEBRA_ROUTE_BGP;
+
+ if (is_bgp_static_route == false && afi == AFI_IP &&
+ CHECK_FLAG(pi->attr->flag, ATTR_FLAG_BIT(BGP_ATTR_NEXT_HOP)) &&
+ (pi->attr->nexthop.s_addr == INADDR_ANY ||
+ !ipv4_unicast_valid(&pi->attr->nexthop))) {
+ /* IPv4 nexthop in standard BGP encoding format.
+ * Format of address is not valid (not any, not unicast).
+ * Fallback to the per VRF label.
+ */
+ bgp_mplsvpn_path_nh_label_unlink(pi);
+ return from_bgp->vpn_policy[afi].tovpn_label;
+ }
+
+ if (is_bgp_static_route == false && afi == AFI_IP &&
+ pi->attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV4 &&
+ (pi->attr->mp_nexthop_global_in.s_addr == INADDR_ANY ||
+ !ipv4_unicast_valid(&pi->attr->mp_nexthop_global_in))) {
+ /* IPv4 nexthop is in MP-BGP encoding format.
+ * Format of address is not valid (not any, not unicast).
+ * Fallback to the per VRF label.
+ */
+ bgp_mplsvpn_path_nh_label_unlink(pi);
+ return from_bgp->vpn_policy[afi].tovpn_label;
+ }
+
+ if (is_bgp_static_route == false && afi == AFI_IP6 &&
+ (pi->attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV6_GLOBAL ||
+ pi->attr->mp_nexthop_len == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL) &&
+ (IN6_IS_ADDR_UNSPECIFIED(&pi->attr->mp_nexthop_global) ||
+ IN6_IS_ADDR_LOOPBACK(&pi->attr->mp_nexthop_global) ||
+ IN6_IS_ADDR_MULTICAST(&pi->attr->mp_nexthop_global))) {
+ /* IPv6 nexthop is in MP-BGP encoding format.
+ * Format of address is not valid
+ * Fallback to the per VRF label.
+ */
+ bgp_mplsvpn_path_nh_label_unlink(pi);
+ return from_bgp->vpn_policy[afi].tovpn_label;
+ }
+
+ /* Check the next-hop reachability.
+ * Get the bgp instance where the bgp_path_info originates.
+ */
+ if (pi->extra && pi->extra->bgp_orig)
+ bgp_nexthop = pi->extra->bgp_orig;
+ else
+ bgp_nexthop = from_bgp;
+
+ nh_afi = BGP_ATTR_NH_AFI(afi, pi->attr);
+ nh_valid = bgp_find_or_add_nexthop(from_bgp, bgp_nexthop, nh_afi, safi,
+ pi, NULL, 0, NULL);
+
+ if (!nh_valid && is_bgp_static_route &&
+ !CHECK_FLAG(from_bgp->flags, BGP_FLAG_IMPORT_CHECK)) {
+ /* "network" prefixes not routable, but since 'no bgp network
+ * import-check' is configured, they are always valid in the BGP
+ * table. Fallback to the per-vrf label
+ */
+ bgp_mplsvpn_path_nh_label_unlink(pi);
+ return from_bgp->vpn_policy[afi].tovpn_label;
+ }
+
+ if (!nh_valid || !pi->nexthop || pi->nexthop->nexthop_num == 0 ||
+ !pi->nexthop->nexthop) {
+ /* invalid next-hop:
+ * do not send the per-vrf label
+ * otherwise, when the next-hop becomes valid,
+ * we will have 2 BGP updates:
+ * - one with the per-vrf label
+ * - the second with the per-nexthop label
+ */
+ bgp_mplsvpn_path_nh_label_unlink(pi);
+ return MPLS_INVALID_LABEL;
+ }
+
+ if (pi->nexthop->nexthop_num > 1 ||
+ pi->nexthop->nexthop->type == NEXTHOP_TYPE_BLACKHOLE) {
+ /* Blackhole or ECMP routes
+ * is not compatible with per-nexthop label.
+ * Fallback to per-vrf label.
+ */
+ bgp_mplsvpn_path_nh_label_unlink(pi);
+ return from_bgp->vpn_policy[afi].tovpn_label;
+ }
+
+ return _vpn_leak_from_vrf_get_per_nexthop_label(pi, to_bgp, from_bgp,
+ afi, safi);
+}
+
/* cf vnc_import_bgp_add_route_mode_nvegroup() and add_vnc_route() */
void vpn_leak_from_vrf_update(struct bgp *to_bgp, /* to */
struct bgp *from_bgp, /* from */
nexthop_self_flag = 1;
}
- label_val = from_bgp->vpn_policy[afi].tovpn_label;
+ if (CHECK_FLAG(from_bgp->vpn_policy[afi].flags,
+ BGP_VPN_POLICY_TOVPN_LABEL_PER_NEXTHOP))
+ /* per nexthop label mode */
+ label_val = vpn_leak_from_vrf_get_per_nexthop_label(
+ afi, safi, path_vrf, from_bgp, to_bgp);
+ else
+ /* per VRF label mode */
+ label_val = from_bgp->vpn_policy[afi].tovpn_label;
+
+ if (label_val == MPLS_INVALID_LABEL &&
+ CHECK_FLAG(from_bgp->vpn_policy[afi].flags,
+ BGP_VPN_POLICY_TOVPN_LABEL_PER_NEXTHOP)) {
+ /* no valid label for the moment
+ * when the 'bgp_mplsvpn_get_label_per_nexthop_cb' callback gets
+ * a valid label value, it will call the current function again.
+ */
+ if (debug)
+ zlog_debug(
+ "%s: %s skipping: waiting for a valid per-label nexthop.",
+ __func__, from_bgp->name_pretty);
+ return;
+ }
if (label_val == MPLS_LABEL_NONE)
encode_label(MPLS_LABEL_IMPLICIT_NULL, &label);
else
bpi, afi, safi);
bgp_path_info_delete(bn, bpi);
bgp_process(to_bgp, bn, afi, safi);
+ bgp_mplsvpn_path_nh_label_unlink(
+ bpi->extra->parent);
}
}
}
#include "bgpd/bgp_flowspec_util.h"
#include "bgpd/bgp_evpn.h"
#include "bgpd/bgp_rd.h"
+#include "bgpd/bgp_mplsvpn.h"
extern struct zclient *zclient;
{
struct bgp_nexthop_cache *bnc = path->nexthop;
+ bgp_mplsvpn_path_nh_label_unlink(path);
+
if (!bnc)
return;
SET_FLAG(path->flags, BGP_PATH_IGP_CHANGED);
path_valid = CHECK_FLAG(path->flags, BGP_PATH_VALID);
- if (path_valid != bnc_is_valid_nexthop) {
+ if (path->type == ZEBRA_ROUTE_BGP &&
+ path->sub_type == BGP_ROUTE_STATIC &&
+ !CHECK_FLAG(bgp_path->flags, BGP_FLAG_IMPORT_CHECK))
+ /* static routes with 'no bgp network import-check' are
+ * always valid. if nht is called with static routes,
+ * the vpn exportation needs to be triggered
+ */
+ vpn_leak_from_vrf_update(bgp_get_default(), bgp_path,
+ path);
+ else if (path_valid != bnc_is_valid_nexthop) {
if (path_valid) {
/* No longer valid, clear flag; also for EVPN
* routes, unimport from VRFs if needed.
bgp_evpn_is_prefix_nht_supported(bgp_dest_get_prefix(dest)))
bgp_evpn_unimport_route(bgp_path,
afi, safi, bgp_dest_get_prefix(dest), path);
+ if (safi == SAFI_UNICAST &&
+ (bgp_path->inst_type !=
+ BGP_INSTANCE_TYPE_VIEW))
+ vpn_leak_from_vrf_withdraw(
+ bgp_get_default(), bgp_path,
+ path);
} else {
/* Path becomes valid, set flag; also for EVPN
* routes, import from VRFs if needed.
bgp_evpn_is_prefix_nht_supported(bgp_dest_get_prefix(dest)))
bgp_evpn_import_route(bgp_path,
afi, safi, bgp_dest_get_prefix(dest), path);
+ if (safi == SAFI_UNICAST &&
+ (bgp_path->inst_type !=
+ BGP_INSTANCE_TYPE_VIEW))
+ vpn_leak_from_vrf_update(
+ bgp_get_default(), bgp_path,
+ path);
}
}
projects / mirror_frr.git / commitdiff