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Diffstat (limited to '')
| -rw-r--r-- | zebra/zebra_rnh.c | 1414 |
1 files changed, 1414 insertions, 0 deletions
diff --git a/zebra/zebra_rnh.c b/zebra/zebra_rnh.c new file mode 100644 index 0000000..7934a9d --- /dev/null +++ b/zebra/zebra_rnh.c @@ -0,0 +1,1414 @@ +/* Zebra next hop tracking code + * Copyright (C) 2013 Cumulus Networks, Inc. + * + * This file is part of GNU Zebra. + * + * GNU Zebra is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2, or (at your option) any + * later version. + * + * GNU Zebra is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; see the file COPYING; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <zebra.h> + +#include "prefix.h" +#include "table.h" +#include "memory.h" +#include "command.h" +#include "if.h" +#include "log.h" +#include "sockunion.h" +#include "linklist.h" +#include "thread.h" +#include "workqueue.h" +#include "prefix.h" +#include "routemap.h" +#include "stream.h" +#include "nexthop.h" +#include "vrf.h" + +#include "zebra/zebra_router.h" +#include "zebra/rib.h" +#include "zebra/rt.h" +#include "zebra/zserv.h" +#include "zebra/zebra_ns.h" +#include "zebra/zebra_vrf.h" +#include "zebra/redistribute.h" +#include "zebra/debug.h" +#include "zebra/zebra_rnh.h" +#include "zebra/zebra_routemap.h" +#include "zebra/zebra_srte.h" +#include "zebra/interface.h" +#include "zebra/zebra_errors.h" + +DEFINE_MTYPE_STATIC(ZEBRA, RNH, "Nexthop tracking object"); + +/* UI controls whether to notify about changes that only involve backup + * nexthops. Default is to notify all changes. + */ +static bool rnh_hide_backups; + +static void free_state(vrf_id_t vrf_id, struct route_entry *re, + struct route_node *rn); +static void copy_state(struct rnh *rnh, const struct route_entry *re, + struct route_node *rn); +static bool compare_state(struct route_entry *r1, struct route_entry *r2); +static void print_rnh(struct route_node *rn, struct vty *vty); +static int zebra_client_cleanup_rnh(struct zserv *client); + +void zebra_rnh_init(void) +{ + hook_register(zserv_client_close, zebra_client_cleanup_rnh); +} + +static inline struct route_table *get_rnh_table(vrf_id_t vrfid, afi_t afi, + safi_t safi) +{ + struct zebra_vrf *zvrf; + struct route_table *t = NULL; + + zvrf = zebra_vrf_lookup_by_id(vrfid); + if (zvrf) { + if (safi == SAFI_UNICAST) + t = zvrf->rnh_table[afi]; + else if (safi == SAFI_MULTICAST) + t = zvrf->rnh_table_multicast[afi]; + } + + return t; +} + +static void zebra_rnh_remove_from_routing_table(struct rnh *rnh) +{ + struct zebra_vrf *zvrf = zebra_vrf_lookup_by_id(rnh->vrf_id); + struct route_table *table = zvrf->table[rnh->afi][rnh->safi]; + struct route_node *rn; + rib_dest_t *dest; + + if (!table) + return; + + rn = route_node_match(table, &rnh->resolved_route); + if (!rn) + return; + + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: %s(%u):%pRN removed from tracking on %pRN", + __func__, VRF_LOGNAME(zvrf->vrf), rnh->vrf_id, + rnh->node, rn); + + dest = rib_dest_from_rnode(rn); + rnh_list_del(&dest->nht, rnh); + route_unlock_node(rn); +} + +static void zebra_rnh_store_in_routing_table(struct rnh *rnh) +{ + struct zebra_vrf *zvrf = zebra_vrf_lookup_by_id(rnh->vrf_id); + struct route_table *table = zvrf->table[rnh->afi][rnh->safi]; + struct route_node *rn; + rib_dest_t *dest; + + rn = route_node_match(table, &rnh->resolved_route); + if (!rn) + return; + + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: %s(%u):%pRN added for tracking on %pRN", + __func__, VRF_LOGNAME(zvrf->vrf), rnh->vrf_id, + rnh->node, rn); + + dest = rib_dest_from_rnode(rn); + rnh_list_add_tail(&dest->nht, rnh); + route_unlock_node(rn); +} + +struct rnh *zebra_add_rnh(struct prefix *p, vrf_id_t vrfid, safi_t safi, + bool *exists) +{ + struct route_table *table; + struct route_node *rn; + struct rnh *rnh = NULL; + afi_t afi = family2afi(p->family); + + if (IS_ZEBRA_DEBUG_NHT) { + struct vrf *vrf = vrf_lookup_by_id(vrfid); + + zlog_debug("%s(%u): Add RNH %pFX for safi: %u", + VRF_LOGNAME(vrf), vrfid, p, safi); + } + + table = get_rnh_table(vrfid, afi, safi); + if (!table) { + struct vrf *vrf = vrf_lookup_by_id(vrfid); + + flog_warn(EC_ZEBRA_RNH_NO_TABLE, + "%s(%u): Add RNH %pFX - table not found", + VRF_LOGNAME(vrf), vrfid, p); + *exists = false; + return NULL; + } + + /* Make it sure prefixlen is applied to the prefix. */ + apply_mask(p); + + /* Lookup (or add) route node.*/ + rn = route_node_get(table, p); + + if (!rn->info) { + rnh = XCALLOC(MTYPE_RNH, sizeof(struct rnh)); + + /* + * The resolved route is already 0.0.0.0/0 or + * 0::0/0 due to the calloc right above, but + * we should set the family so that future + * comparisons can just be done + */ + rnh->resolved_route.family = p->family; + rnh->client_list = list_new(); + rnh->vrf_id = vrfid; + rnh->seqno = 0; + rnh->afi = afi; + rnh->safi = safi; + rnh->zebra_pseudowire_list = list_new(); + route_lock_node(rn); + rn->info = rnh; + rnh->node = rn; + *exists = false; + + zebra_rnh_store_in_routing_table(rnh); + } else + *exists = true; + + route_unlock_node(rn); + return (rn->info); +} + +struct rnh *zebra_lookup_rnh(struct prefix *p, vrf_id_t vrfid, safi_t safi) +{ + struct route_table *table; + struct route_node *rn; + + table = get_rnh_table(vrfid, family2afi(PREFIX_FAMILY(p)), safi); + if (!table) + return NULL; + + /* Make it sure prefixlen is applied to the prefix. */ + apply_mask(p); + + /* Lookup route node.*/ + rn = route_node_lookup(table, p); + if (!rn) + return NULL; + + route_unlock_node(rn); + return (rn->info); +} + +void zebra_free_rnh(struct rnh *rnh) +{ + struct zebra_vrf *zvrf; + struct route_table *table; + + zebra_rnh_remove_from_routing_table(rnh); + rnh->flags |= ZEBRA_NHT_DELETED; + list_delete(&rnh->client_list); + list_delete(&rnh->zebra_pseudowire_list); + + zvrf = zebra_vrf_lookup_by_id(rnh->vrf_id); + table = zvrf->table[family2afi(rnh->resolved_route.family)][rnh->safi]; + + if (table) { + struct route_node *rern; + + rern = route_node_match(table, &rnh->resolved_route); + if (rern) { + rib_dest_t *dest; + + route_unlock_node(rern); + + dest = rib_dest_from_rnode(rern); + rnh_list_del(&dest->nht, rnh); + } + } + free_state(rnh->vrf_id, rnh->state, rnh->node); + XFREE(MTYPE_RNH, rnh); +} + +static void zebra_delete_rnh(struct rnh *rnh) +{ + struct route_node *rn; + + if (!list_isempty(rnh->client_list) + || !list_isempty(rnh->zebra_pseudowire_list)) + return; + + if ((rnh->flags & ZEBRA_NHT_DELETED) || !(rn = rnh->node)) + return; + + if (IS_ZEBRA_DEBUG_NHT) { + struct vrf *vrf = vrf_lookup_by_id(rnh->vrf_id); + + zlog_debug("%s(%u): Del RNH %pRN", VRF_LOGNAME(vrf), + rnh->vrf_id, rnh->node); + } + + zebra_free_rnh(rnh); + rn->info = NULL; + route_unlock_node(rn); +} + +/* + * This code will send to the registering client + * the looked up rnh. + * For a rnh that was created, there is no data + * so it will send an empty nexthop group + * If rnh exists then we know it has been evaluated + * and as such it will have a resolved rnh. + */ +void zebra_add_rnh_client(struct rnh *rnh, struct zserv *client, + vrf_id_t vrf_id) +{ + if (IS_ZEBRA_DEBUG_NHT) { + struct vrf *vrf = vrf_lookup_by_id(vrf_id); + + zlog_debug("%s(%u): Client %s registers for RNH %pRN", + VRF_LOGNAME(vrf), vrf_id, + zebra_route_string(client->proto), rnh->node); + } + if (!listnode_lookup(rnh->client_list, client)) + listnode_add(rnh->client_list, client); + + /* + * We always need to respond with known information, + * currently multiple daemons expect this behavior + */ + zebra_send_rnh_update(rnh, client, vrf_id, 0); +} + +void zebra_remove_rnh_client(struct rnh *rnh, struct zserv *client) +{ + if (IS_ZEBRA_DEBUG_NHT) { + struct vrf *vrf = vrf_lookup_by_id(rnh->vrf_id); + + zlog_debug("Client %s unregisters for RNH %s(%u)%pRN", + zebra_route_string(client->proto), VRF_LOGNAME(vrf), + vrf->vrf_id, rnh->node); + } + listnode_delete(rnh->client_list, client); + zebra_delete_rnh(rnh); +} + +/* XXX move this utility function elsewhere? */ +static void addr2hostprefix(int af, const union g_addr *addr, + struct prefix *prefix) +{ + switch (af) { + case AF_INET: + prefix->family = AF_INET; + prefix->prefixlen = IPV4_MAX_BITLEN; + prefix->u.prefix4 = addr->ipv4; + break; + case AF_INET6: + prefix->family = AF_INET6; + prefix->prefixlen = IPV6_MAX_BITLEN; + prefix->u.prefix6 = addr->ipv6; + break; + default: + memset(prefix, 0, sizeof(*prefix)); + zlog_warn("%s: unknown address family %d", __func__, af); + break; + } +} + +void zebra_register_rnh_pseudowire(vrf_id_t vrf_id, struct zebra_pw *pw, + bool *nht_exists) +{ + struct prefix nh; + struct rnh *rnh; + bool exists; + struct zebra_vrf *zvrf; + + *nht_exists = false; + + zvrf = vrf_info_lookup(vrf_id); + if (!zvrf) + return; + + addr2hostprefix(pw->af, &pw->nexthop, &nh); + rnh = zebra_add_rnh(&nh, vrf_id, SAFI_UNICAST, &exists); + if (!rnh) + return; + + if (!listnode_lookup(rnh->zebra_pseudowire_list, pw)) { + listnode_add(rnh->zebra_pseudowire_list, pw); + pw->rnh = rnh; + zebra_evaluate_rnh(zvrf, family2afi(pw->af), 1, &nh, + SAFI_UNICAST); + } else + *nht_exists = true; +} + +void zebra_deregister_rnh_pseudowire(vrf_id_t vrf_id, struct zebra_pw *pw) +{ + struct rnh *rnh; + + rnh = pw->rnh; + if (!rnh) + return; + + listnode_delete(rnh->zebra_pseudowire_list, pw); + pw->rnh = NULL; + + zebra_delete_rnh(rnh); +} + +/* Clear the NEXTHOP_FLAG_RNH_FILTERED flags on all nexthops + */ +static void zebra_rnh_clear_nexthop_rnh_filters(struct route_entry *re) +{ + struct nexthop *nexthop; + + if (re) { + for (nexthop = re->nhe->nhg.nexthop; nexthop; + nexthop = nexthop->next) { + UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_RNH_FILTERED); + } + } +} + +/* Apply the NHT route-map for a client to the route (and nexthops) + * resolving a NH. + */ +static int zebra_rnh_apply_nht_rmap(afi_t afi, struct zebra_vrf *zvrf, + struct route_node *prn, + struct route_entry *re, int proto) +{ + int at_least_one = 0; + struct nexthop *nexthop; + route_map_result_t ret; + + if (prn && re) { + for (nexthop = re->nhe->nhg.nexthop; nexthop; + nexthop = nexthop->next) { + ret = zebra_nht_route_map_check( + afi, proto, &prn->p, zvrf, re, nexthop); + if (ret != RMAP_DENYMATCH) + at_least_one++; /* at least one valid NH */ + else { + SET_FLAG(nexthop->flags, + NEXTHOP_FLAG_RNH_FILTERED); + } + } + } + return (at_least_one); +} + +/* + * Notify clients registered for this nexthop about a change. + */ +static void zebra_rnh_notify_protocol_clients(struct zebra_vrf *zvrf, afi_t afi, + struct route_node *nrn, + struct rnh *rnh, + struct route_node *prn, + struct route_entry *re) +{ + struct listnode *node; + struct zserv *client; + int num_resolving_nh; + + if (IS_ZEBRA_DEBUG_NHT) { + if (prn && re) { + zlog_debug("%s(%u):%pRN: NH resolved over route %pRN", + VRF_LOGNAME(zvrf->vrf), zvrf->vrf->vrf_id, + nrn, prn); + } else + zlog_debug("%s(%u):%pRN: NH has become unresolved", + VRF_LOGNAME(zvrf->vrf), zvrf->vrf->vrf_id, + nrn); + } + + for (ALL_LIST_ELEMENTS_RO(rnh->client_list, node, client)) { + if (prn && re) { + /* Apply route-map for this client to route resolving + * this + * nexthop to see if it is filtered or not. + */ + zebra_rnh_clear_nexthop_rnh_filters(re); + num_resolving_nh = zebra_rnh_apply_nht_rmap( + afi, zvrf, prn, re, client->proto); + if (num_resolving_nh) + rnh->filtered[client->proto] = 0; + else + rnh->filtered[client->proto] = 1; + + if (IS_ZEBRA_DEBUG_NHT) + zlog_debug( + "%s(%u):%pRN: Notifying client %s about NH %s", + VRF_LOGNAME(zvrf->vrf), + zvrf->vrf->vrf_id, nrn, + zebra_route_string(client->proto), + num_resolving_nh + ? "" + : "(filtered by route-map)"); + } else { + rnh->filtered[client->proto] = 0; + if (IS_ZEBRA_DEBUG_NHT) + zlog_debug( + "%s(%u):%pRN: Notifying client %s about NH (unreachable)", + VRF_LOGNAME(zvrf->vrf), + zvrf->vrf->vrf_id, nrn, + zebra_route_string(client->proto)); + } + + zebra_send_rnh_update(rnh, client, zvrf->vrf->vrf_id, 0); + } + + if (re) + zebra_rnh_clear_nexthop_rnh_filters(re); +} + +/* + * Utility to determine whether a candidate nexthop is useable. We make this + * check in a couple of places, so this is a single home for the logic we + * use. + */ + +static const int RNH_INVALID_NH_FLAGS = (NEXTHOP_FLAG_RECURSIVE | + NEXTHOP_FLAG_DUPLICATE | + NEXTHOP_FLAG_RNH_FILTERED); + +bool rnh_nexthop_valid(const struct route_entry *re, const struct nexthop *nh) +{ + return (CHECK_FLAG(re->status, ROUTE_ENTRY_INSTALLED) + && CHECK_FLAG(nh->flags, NEXTHOP_FLAG_ACTIVE) + && !CHECK_FLAG(nh->flags, RNH_INVALID_NH_FLAGS)); +} + +/* + * Determine whether an re's nexthops are valid for tracking. + */ +static bool rnh_check_re_nexthops(const struct route_entry *re, + const struct rnh *rnh) +{ + bool ret = false; + const struct nexthop *nexthop = NULL; + + /* Check route's nexthops */ + for (ALL_NEXTHOPS(re->nhe->nhg, nexthop)) { + if (rnh_nexthop_valid(re, nexthop)) + break; + } + + /* Check backup nexthops, if any. */ + if (nexthop == NULL && re->nhe->backup_info && + re->nhe->backup_info->nhe) { + for (ALL_NEXTHOPS(re->nhe->backup_info->nhe->nhg, nexthop)) { + if (rnh_nexthop_valid(re, nexthop)) + break; + } + } + + if (nexthop == NULL) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug( + " Route Entry %s no nexthops", + zebra_route_string(re->type)); + + goto done; + } + + /* Some special checks if registration asked for them. */ + if (CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED)) { + if ((re->type == ZEBRA_ROUTE_CONNECT) + || (re->type == ZEBRA_ROUTE_STATIC)) + ret = true; + if (re->type == ZEBRA_ROUTE_NHRP) { + + for (nexthop = re->nhe->nhg.nexthop; + nexthop; + nexthop = nexthop->next) + if (nexthop->type == NEXTHOP_TYPE_IFINDEX) + break; + if (nexthop) + ret = true; + } + } else { + ret = true; + } + +done: + return ret; +} + +/* + * Determine appropriate route (route entry) resolving a tracked + * nexthop. + */ +static struct route_entry * +zebra_rnh_resolve_nexthop_entry(struct zebra_vrf *zvrf, afi_t afi, + struct route_node *nrn, const struct rnh *rnh, + struct route_node **prn) +{ + struct route_table *route_table; + struct route_node *rn; + struct route_entry *re; + + *prn = NULL; + + route_table = zvrf->table[afi][rnh->safi]; + if (!route_table) + return NULL; + + rn = route_node_match(route_table, &nrn->p); + if (!rn) + return NULL; + + /* Unlock route node - we don't need to lock when walking the tree. */ + route_unlock_node(rn); + + /* While resolving nexthops, we may need to walk up the tree from the + * most-specific match. Do similar logic as in zebra_rib.c + */ + while (rn) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: %s(%u):%pRN Possible Match to %pRN", + __func__, VRF_LOGNAME(zvrf->vrf), + rnh->vrf_id, rnh->node, rn); + + /* Do not resolve over default route unless allowed && + * match route to be exact if so specified + */ + if (is_default_prefix(&rn->p) + && (!CHECK_FLAG(rnh->flags, ZEBRA_NHT_RESOLVE_VIA_DEFAULT) + && !rnh_resolve_via_default(zvrf, rn->p.family))) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug( + " Not allowed to resolve through default prefix: rnh->resolve_via_default: %u", + CHECK_FLAG( + rnh->flags, + ZEBRA_NHT_RESOLVE_VIA_DEFAULT)); + return NULL; + } + + /* Identify appropriate route entry. */ + RNODE_FOREACH_RE (rn, re) { + if (CHECK_FLAG(re->status, ROUTE_ENTRY_REMOVED)) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug( + " Route Entry %s removed", + zebra_route_string(re->type)); + continue; + } + if (!CHECK_FLAG(re->flags, ZEBRA_FLAG_SELECTED) && + !CHECK_FLAG(re->flags, ZEBRA_FLAG_FIB_OVERRIDE)) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug( + " Route Entry %s !selected", + zebra_route_string(re->type)); + continue; + } + + if (CHECK_FLAG(re->status, ROUTE_ENTRY_QUEUED)) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug( + " Route Entry %s queued", + zebra_route_string(re->type)); + continue; + } + + /* Just being SELECTED isn't quite enough - must + * have an installed nexthop to be useful. + */ + if (rnh_check_re_nexthops(re, rnh)) + break; + } + + /* Route entry found, we're done; else, walk up the tree. */ + if (re) { + *prn = rn; + return re; + } else { + /* Resolve the nexthop recursively by finding matching + * route with lower prefix length + */ + rn = rn->parent; + } + } + + return NULL; +} + +static void zebra_rnh_process_pseudowires(vrf_id_t vrfid, struct rnh *rnh) +{ + struct zebra_pw *pw; + struct listnode *node; + + for (ALL_LIST_ELEMENTS_RO(rnh->zebra_pseudowire_list, node, pw)) + zebra_pw_update(pw); +} + +/* + * See if a tracked nexthop entry has undergone any change, and if so, + * take appropriate action; this involves notifying any clients and/or + * scheduling dependent static routes for processing. + */ +static void zebra_rnh_eval_nexthop_entry(struct zebra_vrf *zvrf, afi_t afi, + int force, struct route_node *nrn, + struct rnh *rnh, + struct route_node *prn, + struct route_entry *re) +{ + int state_changed = 0; + + /* If we're resolving over a different route, resolution has changed or + * the resolving route has some change (e.g., metric), there is a state + * change. + */ + zebra_rnh_remove_from_routing_table(rnh); + if (!prefix_same(&rnh->resolved_route, prn ? &prn->p : NULL)) { + if (prn) + prefix_copy(&rnh->resolved_route, &prn->p); + else { + /* + * Just quickly store the family of the resolved + * route so that we can reset it in a second here + */ + int family = rnh->resolved_route.family; + + memset(&rnh->resolved_route, 0, sizeof(struct prefix)); + rnh->resolved_route.family = family; + } + + copy_state(rnh, re, nrn); + state_changed = 1; + } else if (compare_state(re, rnh->state)) { + copy_state(rnh, re, nrn); + state_changed = 1; + } + zebra_rnh_store_in_routing_table(rnh); + + if (state_changed || force) { + /* NOTE: Use the "copy" of resolving route stored in 'rnh' i.e., + * rnh->state. + */ + /* Notify registered protocol clients. */ + zebra_rnh_notify_protocol_clients(zvrf, afi, nrn, rnh, prn, + rnh->state); + + /* Process pseudowires attached to this nexthop */ + zebra_rnh_process_pseudowires(zvrf->vrf->vrf_id, rnh); + } +} + +/* Evaluate one tracked entry */ +static void zebra_rnh_evaluate_entry(struct zebra_vrf *zvrf, afi_t afi, + int force, struct route_node *nrn) +{ + struct rnh *rnh; + struct route_entry *re; + struct route_node *prn; + + if (IS_ZEBRA_DEBUG_NHT) { + zlog_debug("%s(%u):%pRN: Evaluate RNH, %s", + VRF_LOGNAME(zvrf->vrf), zvrf->vrf->vrf_id, nrn, + force ? "(force)" : ""); + } + + rnh = nrn->info; + + /* Identify route entry (RE) resolving this tracked entry. */ + re = zebra_rnh_resolve_nexthop_entry(zvrf, afi, nrn, rnh, &prn); + + /* If the entry cannot be resolved and that is also the existing state, + * there is nothing further to do. + */ + if (!re && rnh->state == NULL && !force) + return; + + /* Process based on type of entry. */ + zebra_rnh_eval_nexthop_entry(zvrf, afi, force, nrn, rnh, prn, re); +} + +/* + * Clear the ROUTE_ENTRY_NEXTHOPS_CHANGED flag + * from the re entries. + * + * Please note we are doing this *after* we have + * notified the world about each nexthop as that + * we can have a situation where one re entry + * covers multiple nexthops we are interested in. + */ +static void zebra_rnh_clear_nhc_flag(struct zebra_vrf *zvrf, afi_t afi, + struct route_node *nrn) +{ + struct rnh *rnh; + struct route_entry *re; + struct route_node *prn; + + rnh = nrn->info; + + /* Identify route entry (RIB) resolving this tracked entry. */ + re = zebra_rnh_resolve_nexthop_entry(zvrf, afi, nrn, rnh, &prn); + + if (re) + UNSET_FLAG(re->status, ROUTE_ENTRY_LABELS_CHANGED); +} + +/* Evaluate all tracked entries (nexthops or routes for import into BGP) + * of a particular VRF and address-family or a specific prefix. + */ +void zebra_evaluate_rnh(struct zebra_vrf *zvrf, afi_t afi, int force, + const struct prefix *p, safi_t safi) +{ + struct route_table *rnh_table; + struct route_node *nrn; + + rnh_table = get_rnh_table(zvrf->vrf->vrf_id, afi, safi); + if (!rnh_table) // unexpected + return; + + if (p) { + /* Evaluating a specific entry, make sure it exists. */ + nrn = route_node_lookup(rnh_table, p); + if (nrn && nrn->info) + zebra_rnh_evaluate_entry(zvrf, afi, force, nrn); + + if (nrn) + route_unlock_node(nrn); + } else { + /* Evaluate entire table. */ + nrn = route_top(rnh_table); + while (nrn) { + if (nrn->info) + zebra_rnh_evaluate_entry(zvrf, afi, force, nrn); + nrn = route_next(nrn); /* this will also unlock nrn */ + } + nrn = route_top(rnh_table); + while (nrn) { + if (nrn->info) + zebra_rnh_clear_nhc_flag(zvrf, afi, nrn); + nrn = route_next(nrn); /* this will also unlock nrn */ + } + } +} + +void zebra_print_rnh_table(vrf_id_t vrfid, afi_t afi, safi_t safi, + struct vty *vty, const struct prefix *p) +{ + struct route_table *table; + struct route_node *rn; + + table = get_rnh_table(vrfid, afi, safi); + if (!table) { + if (IS_ZEBRA_DEBUG_NHT) + zlog_debug("print_rnhs: rnh table not found"); + return; + } + + for (rn = route_top(table); rn; rn = route_next(rn)) { + if (p && !prefix_match(&rn->p, p)) + continue; + + if (rn->info) + print_rnh(rn, vty); + } +} + +/** + * free_state - free up the re structure associated with the rnh. + */ +static void free_state(vrf_id_t vrf_id, struct route_entry *re, + struct route_node *rn) +{ + if (!re) + return; + + /* free RE and nexthops */ + zebra_nhg_free(re->nhe); + XFREE(MTYPE_RE, re); +} + +static void copy_state(struct rnh *rnh, const struct route_entry *re, + struct route_node *rn) +{ + struct route_entry *state; + + if (rnh->state) { + free_state(rnh->vrf_id, rnh->state, rn); + rnh->state = NULL; + } + + if (!re) + return; + + state = XCALLOC(MTYPE_RE, sizeof(struct route_entry)); + state->type = re->type; + state->distance = re->distance; + state->metric = re->metric; + state->vrf_id = re->vrf_id; + state->status = re->status; + + state->nhe = zebra_nhe_copy(re->nhe, 0); + + /* Copy the 'fib' nexthops also, if present - we want to capture + * the true installed nexthops. + */ + if (re->fib_ng.nexthop) + nexthop_group_copy(&state->fib_ng, &re->fib_ng); + if (re->fib_backup_ng.nexthop) + nexthop_group_copy(&state->fib_backup_ng, &re->fib_backup_ng); + + rnh->state = state; +} + +/* + * Locate the next primary nexthop, used when comparing current rnh info with + * an updated route. + */ +static struct nexthop *next_valid_primary_nh(struct route_entry *re, + struct nexthop *nh) +{ + struct nexthop_group *nhg; + struct nexthop *bnh; + int i, idx; + bool default_path = true; + + /* Fib backup ng present: some backups are installed, + * and we're configured for special handling if there are backups. + */ + if (rnh_hide_backups && (re->fib_backup_ng.nexthop != NULL)) + default_path = false; + + /* Default path: no special handling, just using the 'installed' + * primary nexthops and the common validity test. + */ + if (default_path) { + if (nh == NULL) { + nhg = rib_get_fib_nhg(re); + nh = nhg->nexthop; + } else + nh = nexthop_next(nh); + + while (nh) { + if (rnh_nexthop_valid(re, nh)) + break; + else + nh = nexthop_next(nh); + } + + return nh; + } + + /* Hide backup activation/switchover events. + * + * If we've had a switchover, an inactive primary won't be in + * the fib list at all - the 'fib' list could even be empty + * in the case where no primary is installed. But we want to consider + * those primaries "valid" if they have an activated backup nh. + * + * The logic is something like: + * if (!fib_nhg) + * // then all primaries are installed + * else + * for each primary in re nhg + * if in fib_nhg + * primary is installed + * else if a backup is installed + * primary counts as installed + * else + * primary !installed + */ + + /* Start with the first primary */ + if (nh == NULL) + nh = re->nhe->nhg.nexthop; + else + nh = nexthop_next(nh); + + while (nh) { + + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: checking primary NH %pNHv", + __func__, nh); + + /* If this nexthop is in the fib list, it's installed */ + nhg = rib_get_fib_nhg(re); + + for (bnh = nhg->nexthop; bnh; bnh = nexthop_next(bnh)) { + if (nexthop_cmp(nh, bnh) == 0) + break; + } + + if (bnh != NULL) { + /* Found the match */ + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: NH in fib list", __func__); + break; + } + + /* Else if this nexthop's backup is installed, it counts */ + nhg = rib_get_fib_backup_nhg(re); + bnh = nhg->nexthop; + + for (idx = 0; bnh != NULL; idx++) { + /* If we find an active backup nh for this + * primary, we're done; + */ + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: checking backup %pNHv [%d]", + __func__, bnh, idx); + + if (!CHECK_FLAG(bnh->flags, NEXTHOP_FLAG_ACTIVE)) + continue; + + for (i = 0; i < nh->backup_num; i++) { + /* Found a matching activated backup nh */ + if (nh->backup_idx[i] == idx) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: backup %d activated", + __func__, i); + + goto done; + } + } + + /* Note that we're not recursing here if the + * backups are recursive: the primary's index is + * only valid in the top-level backup list. + */ + bnh = bnh->next; + } + + /* Try the next primary nexthop */ + nh = nexthop_next(nh); + } + +done: + + return nh; +} + +/* + * Compare two route_entries' nexthops. Account for backup nexthops + * and for the 'fib' nexthop lists, if present. + */ +static bool compare_valid_nexthops(struct route_entry *r1, + struct route_entry *r2) +{ + bool matched_p = false; + struct nexthop_group *nhg1, *nhg2; + struct nexthop *nh1, *nh2; + + /* Start with the primary nexthops */ + + nh1 = next_valid_primary_nh(r1, NULL); + nh2 = next_valid_primary_nh(r2, NULL); + + while (1) { + /* Find any differences in the nexthop lists */ + + if (nh1 && nh2) { + /* Any difference is a no-match */ + if (nexthop_cmp(nh1, nh2) != 0) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: nh1: %pNHv, nh2: %pNHv differ", + __func__, nh1, nh2); + goto done; + } + + } else if (nh1 || nh2) { + /* One list has more valid nexthops than the other */ + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: nh1 %s, nh2 %s", __func__, + nh1 ? "non-NULL" : "NULL", + nh2 ? "non-NULL" : "NULL"); + goto done; + } else + break; /* Done with both lists */ + + nh1 = next_valid_primary_nh(r1, nh1); + nh2 = next_valid_primary_nh(r2, nh2); + } + + /* If configured, don't compare installed backup state - we've + * accounted for that with the primaries above. + * + * But we do want to compare the routes' backup info, + * in case the owning route has changed the backups - + * that change we do want to report. + */ + if (rnh_hide_backups) { + uint32_t hash1 = 0, hash2 = 0; + + if (r1->nhe->backup_info) + hash1 = nexthop_group_hash( + &r1->nhe->backup_info->nhe->nhg); + + if (r2->nhe->backup_info) + hash2 = nexthop_group_hash( + &r2->nhe->backup_info->nhe->nhg); + + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: backup hash1 %#x, hash2 %#x", + __func__, hash1, hash2); + + if (hash1 != hash2) + goto done; + else + goto finished; + } + + /* The test for the backups is slightly different: the only installed + * backups will be in the 'fib' list. + */ + nhg1 = rib_get_fib_backup_nhg(r1); + nhg2 = rib_get_fib_backup_nhg(r2); + + nh1 = nhg1->nexthop; + nh2 = nhg2->nexthop; + + while (1) { + /* Find each backup list's next valid nexthop */ + while ((nh1 != NULL) && !rnh_nexthop_valid(r1, nh1)) + nh1 = nexthop_next(nh1); + + while ((nh2 != NULL) && !rnh_nexthop_valid(r2, nh2)) + nh2 = nexthop_next(nh2); + + if (nh1 && nh2) { + /* Any difference is a no-match */ + if (nexthop_cmp(nh1, nh2) != 0) { + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: backup nh1: %pNHv, nh2: %pNHv differ", + __func__, nh1, nh2); + goto done; + } + + nh1 = nexthop_next(nh1); + nh2 = nexthop_next(nh2); + } else if (nh1 || nh2) { + /* One list has more valid nexthops than the other */ + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: backup nh1 %s, nh2 %s", + __func__, + nh1 ? "non-NULL" : "NULL", + nh2 ? "non-NULL" : "NULL"); + goto done; + } else + break; /* Done with both lists */ + } + +finished: + + /* Well, it's a match */ + matched_p = true; + +done: + + if (IS_ZEBRA_DEBUG_NHT_DETAILED) + zlog_debug("%s: %smatched", + __func__, (matched_p ? "" : "NOT ")); + + return matched_p; +} + +/* Returns 'false' if no difference. */ +static bool compare_state(struct route_entry *r1, + struct route_entry *r2) +{ + if (!r1 && !r2) + return false; + + if ((!r1 && r2) || (r1 && !r2)) + return true; + + if (r1->distance != r2->distance) + return true; + + if (r1->metric != r2->metric) + return true; + + if (!compare_valid_nexthops(r1, r2)) + return true; + + return false; +} + +int zebra_send_rnh_update(struct rnh *rnh, struct zserv *client, + vrf_id_t vrf_id, uint32_t srte_color) +{ + struct stream *s = NULL; + struct route_entry *re; + unsigned long nump; + uint8_t num; + struct nexthop *nh; + struct route_node *rn; + int ret; + uint32_t message = 0; + + rn = rnh->node; + re = rnh->state; + + /* Get output stream. */ + s = stream_new(ZEBRA_MAX_PACKET_SIZ); + + zclient_create_header(s, ZEBRA_NEXTHOP_UPDATE, vrf_id); + + /* Message flags. */ + if (srte_color) + SET_FLAG(message, ZAPI_MESSAGE_SRTE); + stream_putl(s, message); + + /* + * Put what we were told to match against + */ + stream_putw(s, rnh->safi); + stream_putw(s, rn->p.family); + stream_putc(s, rn->p.prefixlen); + switch (rn->p.family) { + case AF_INET: + stream_put_in_addr(s, &rn->p.u.prefix4); + break; + case AF_INET6: + stream_put(s, &rn->p.u.prefix6, IPV6_MAX_BYTELEN); + break; + default: + flog_err(EC_ZEBRA_RNH_UNKNOWN_FAMILY, + "%s: Unknown family (%d) notification attempted", + __func__, rn->p.family); + goto failure; + } + + /* + * What we matched against + */ + stream_putw(s, rnh->resolved_route.family); + stream_putc(s, rnh->resolved_route.prefixlen); + switch (rnh->resolved_route.family) { + case AF_INET: + stream_put_in_addr(s, &rnh->resolved_route.u.prefix4); + break; + case AF_INET6: + stream_put(s, &rnh->resolved_route.u.prefix6, IPV6_MAX_BYTELEN); + break; + default: + flog_err(EC_ZEBRA_RNH_UNKNOWN_FAMILY, + "%s: Unknown family (%d) notification attempted", + __func__, rn->p.family); + goto failure; + } + + if (srte_color) + stream_putl(s, srte_color); + + if (re) { + struct zapi_nexthop znh; + struct nexthop_group *nhg; + + stream_putc(s, re->type); + stream_putw(s, re->instance); + stream_putc(s, re->distance); + stream_putl(s, re->metric); + num = 0; + nump = stream_get_endp(s); + stream_putc(s, 0); + + nhg = rib_get_fib_nhg(re); + for (ALL_NEXTHOPS_PTR(nhg, nh)) + if (rnh_nexthop_valid(re, nh)) { + zapi_nexthop_from_nexthop(&znh, nh); + ret = zapi_nexthop_encode(s, &znh, 0, message); + if (ret < 0) + goto failure; + + num++; + } + + nhg = rib_get_fib_backup_nhg(re); + if (nhg) { + for (ALL_NEXTHOPS_PTR(nhg, nh)) + if (rnh_nexthop_valid(re, nh)) { + zapi_nexthop_from_nexthop(&znh, nh); + ret = zapi_nexthop_encode( + s, &znh, 0 /* flags */, + 0 /* message */); + if (ret < 0) + goto failure; + + num++; + } + } + + stream_putc_at(s, nump, num); + } else { + stream_putc(s, 0); // type + stream_putw(s, 0); // instance + stream_putc(s, 0); // distance + stream_putl(s, 0); // metric + stream_putc(s, 0); // nexthops + } + stream_putw_at(s, 0, stream_get_endp(s)); + + client->nh_last_upd_time = monotime(NULL); + return zserv_send_message(client, s); + +failure: + + stream_free(s); + return -1; +} + +static void print_nh(struct nexthop *nexthop, struct vty *vty) +{ + char buf[BUFSIZ]; + struct zebra_ns *zns = zebra_ns_lookup(nexthop->vrf_id); + + switch (nexthop->type) { + case NEXTHOP_TYPE_IPV4: + case NEXTHOP_TYPE_IPV4_IFINDEX: + vty_out(vty, " via %pI4", &nexthop->gate.ipv4); + if (nexthop->ifindex) + vty_out(vty, ", %s", + ifindex2ifname_per_ns(zns, nexthop->ifindex)); + break; + case NEXTHOP_TYPE_IPV6: + case NEXTHOP_TYPE_IPV6_IFINDEX: + vty_out(vty, " %s", + inet_ntop(AF_INET6, &nexthop->gate.ipv6, buf, BUFSIZ)); + if (nexthop->ifindex) + vty_out(vty, ", via %s", + ifindex2ifname_per_ns(zns, nexthop->ifindex)); + break; + case NEXTHOP_TYPE_IFINDEX: + vty_out(vty, " is directly connected, %s", + ifindex2ifname_per_ns(zns, nexthop->ifindex)); + break; + case NEXTHOP_TYPE_BLACKHOLE: + vty_out(vty, " is directly connected, Null0"); + break; + default: + break; + } + vty_out(vty, "\n"); +} + +static void print_rnh(struct route_node *rn, struct vty *vty) +{ + struct rnh *rnh; + struct nexthop *nexthop; + struct listnode *node; + struct zserv *client; + char buf[BUFSIZ]; + + rnh = rn->info; + vty_out(vty, "%s%s\n", + inet_ntop(rn->p.family, &rn->p.u.prefix, buf, BUFSIZ), + CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED) ? "(Connected)" + : ""); + if (rnh->state) { + vty_out(vty, " resolved via %s\n", + zebra_route_string(rnh->state->type)); + for (nexthop = rnh->state->nhe->nhg.nexthop; nexthop; + nexthop = nexthop->next) + print_nh(nexthop, vty); + } else + vty_out(vty, " unresolved%s\n", + CHECK_FLAG(rnh->flags, ZEBRA_NHT_CONNECTED) + ? "(Connected)" + : ""); + + vty_out(vty, " Client list:"); + for (ALL_LIST_ELEMENTS_RO(rnh->client_list, node, client)) + vty_out(vty, " %s(fd %d)%s", zebra_route_string(client->proto), + client->sock, + rnh->filtered[client->proto] ? "(filtered)" : ""); + if (!list_isempty(rnh->zebra_pseudowire_list)) + vty_out(vty, " zebra[pseudowires]"); + vty_out(vty, "\n"); +} + +static int zebra_cleanup_rnh_client(vrf_id_t vrf_id, afi_t afi, safi_t safi, + struct zserv *client) +{ + struct route_table *ntable; + struct route_node *nrn; + struct rnh *rnh; + + if (IS_ZEBRA_DEBUG_NHT) { + struct vrf *vrf = vrf_lookup_by_id(vrf_id); + + zlog_debug("%s(%u): Client %s RNH cleanup for family %s", + VRF_LOGNAME(vrf), vrf_id, + zebra_route_string(client->proto), afi2str(afi)); + } + + ntable = get_rnh_table(vrf_id, afi, safi); + if (!ntable) { + zlog_debug("cleanup_rnh_client: rnh table not found"); + return -1; + } + + for (nrn = route_top(ntable); nrn; nrn = route_next(nrn)) { + if (!nrn->info) + continue; + + rnh = nrn->info; + zebra_remove_rnh_client(rnh, client); + } + return 1; +} + +/* Cleanup registered nexthops (across VRFs) upon client disconnect. */ +static int zebra_client_cleanup_rnh(struct zserv *client) +{ + struct vrf *vrf; + struct zebra_vrf *zvrf; + + RB_FOREACH (vrf, vrf_id_head, &vrfs_by_id) { + zvrf = vrf->info; + if (zvrf) { + zebra_cleanup_rnh_client(zvrf_id(zvrf), AFI_IP, + SAFI_UNICAST, client); + zebra_cleanup_rnh_client(zvrf_id(zvrf), AFI_IP, + SAFI_MULTICAST, client); + zebra_cleanup_rnh_client(zvrf_id(zvrf), AFI_IP6, + SAFI_UNICAST, client); + zebra_cleanup_rnh_client(zvrf_id(zvrf), AFI_IP6, + SAFI_MULTICAST, client); + } + } + + return 0; +} + +int rnh_resolve_via_default(struct zebra_vrf *zvrf, int family) +{ + if (((family == AF_INET) && zvrf->zebra_rnh_ip_default_route) + || ((family == AF_INET6) && zvrf->zebra_rnh_ipv6_default_route)) + return 1; + else + return 0; +} + +/* + * UI control to avoid notifications if backup nexthop status changes + */ +void rnh_set_hide_backups(bool hide_p) +{ + rnh_hide_backups = hide_p; +} + +bool rnh_get_hide_backups(void) +{ + return rnh_hide_backups; +} |