diff options
Diffstat (limited to 'zebra/zebra_nhg.c')
| -rw-r--r-- | zebra/zebra_nhg.c | 3524 |
1 files changed, 3524 insertions, 0 deletions
diff --git a/zebra/zebra_nhg.c b/zebra/zebra_nhg.c new file mode 100644 index 0000000..e500232 --- /dev/null +++ b/zebra/zebra_nhg.c @@ -0,0 +1,3524 @@ +/* Zebra Nexthop Group Code. + * Copyright (C) 2019 Cumulus Networks, Inc. + * Donald Sharp + * Stephen Worley + * + * This file is part of FRR. + * + * FRR 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. + * + * FRR 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 FRR; see the file COPYING. If not, write to the Free + * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA + * 02111-1307, USA. + */ +#include <zebra.h> + +#include "lib/nexthop.h" +#include "lib/nexthop_group_private.h" +#include "lib/routemap.h" +#include "lib/mpls.h" +#include "lib/jhash.h" +#include "lib/debug.h" +#include "lib/lib_errors.h" + +#include "zebra/connected.h" +#include "zebra/debug.h" +#include "zebra/zebra_router.h" +#include "zebra/zebra_nhg_private.h" +#include "zebra/zebra_rnh.h" +#include "zebra/zebra_routemap.h" +#include "zebra/zebra_srte.h" +#include "zebra/zserv.h" +#include "zebra/rt.h" +#include "zebra_errors.h" +#include "zebra_dplane.h" +#include "zebra/interface.h" +#include "zebra/zapi_msg.h" +#include "zebra/rib.h" + +DEFINE_MTYPE_STATIC(ZEBRA, NHG, "Nexthop Group Entry"); +DEFINE_MTYPE_STATIC(ZEBRA, NHG_CONNECTED, "Nexthop Group Connected"); +DEFINE_MTYPE_STATIC(ZEBRA, NHG_CTX, "Nexthop Group Context"); + +/* Map backup nexthop indices between two nhes */ +struct backup_nh_map_s { + int map_count; + + struct { + uint8_t orig_idx; + uint8_t new_idx; + } map[MULTIPATH_NUM]; +}; + +/* id counter to keep in sync with kernel */ +uint32_t id_counter; + +/* Controlled through ui */ +static bool g_nexthops_enabled = true; +static bool proto_nexthops_only; +static bool use_recursive_backups = true; + +static struct nhg_hash_entry *depends_find(const struct nexthop *nh, afi_t afi, + int type, bool from_dplane); +static void depends_add(struct nhg_connected_tree_head *head, + struct nhg_hash_entry *depend); +static struct nhg_hash_entry * +depends_find_add(struct nhg_connected_tree_head *head, struct nexthop *nh, + afi_t afi, int type, bool from_dplane); +static struct nhg_hash_entry * +depends_find_id_add(struct nhg_connected_tree_head *head, uint32_t id); +static void depends_decrement_free(struct nhg_connected_tree_head *head); + +static struct nhg_backup_info * +nhg_backup_copy(const struct nhg_backup_info *orig); + +/* Helper function for getting the next allocatable ID */ +static uint32_t nhg_get_next_id(void) +{ + while (1) { + id_counter++; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: ID %u checking", __func__, id_counter); + + if (id_counter == ZEBRA_NHG_PROTO_LOWER) { + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: ID counter wrapped", __func__); + + id_counter = 0; + continue; + } + + if (zebra_nhg_lookup_id(id_counter)) { + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: ID already exists", __func__); + + continue; + } + + break; + } + + return id_counter; +} + +static void nhg_connected_free(struct nhg_connected *dep) +{ + XFREE(MTYPE_NHG_CONNECTED, dep); +} + +static struct nhg_connected *nhg_connected_new(struct nhg_hash_entry *nhe) +{ + struct nhg_connected *new = NULL; + + new = XCALLOC(MTYPE_NHG_CONNECTED, sizeof(struct nhg_connected)); + new->nhe = nhe; + + return new; +} + +void nhg_connected_tree_free(struct nhg_connected_tree_head *head) +{ + struct nhg_connected *rb_node_dep = NULL; + + if (!nhg_connected_tree_is_empty(head)) { + frr_each_safe(nhg_connected_tree, head, rb_node_dep) { + nhg_connected_tree_del(head, rb_node_dep); + nhg_connected_free(rb_node_dep); + } + } +} + +bool nhg_connected_tree_is_empty(const struct nhg_connected_tree_head *head) +{ + return nhg_connected_tree_count(head) ? false : true; +} + +struct nhg_connected * +nhg_connected_tree_root(struct nhg_connected_tree_head *head) +{ + return nhg_connected_tree_first(head); +} + +struct nhg_hash_entry * +nhg_connected_tree_del_nhe(struct nhg_connected_tree_head *head, + struct nhg_hash_entry *depend) +{ + struct nhg_connected lookup = {}; + struct nhg_connected *remove = NULL; + struct nhg_hash_entry *removed_nhe; + + lookup.nhe = depend; + + /* Lookup to find the element, then remove it */ + remove = nhg_connected_tree_find(head, &lookup); + if (remove) + /* Re-returning here just in case this API changes.. + * the _del list api's are a bit undefined at the moment. + * + * So hopefully returning here will make it fail if the api + * changes to something different than currently expected. + */ + remove = nhg_connected_tree_del(head, remove); + + /* If the entry was sucessfully removed, free the 'connected` struct */ + if (remove) { + removed_nhe = remove->nhe; + nhg_connected_free(remove); + return removed_nhe; + } + + return NULL; +} + +/* Assuming UNIQUE RB tree. If this changes, assumptions here about + * insertion need to change. + */ +struct nhg_hash_entry * +nhg_connected_tree_add_nhe(struct nhg_connected_tree_head *head, + struct nhg_hash_entry *depend) +{ + struct nhg_connected *new = NULL; + + new = nhg_connected_new(depend); + + /* On success, NULL will be returned from the + * RB code. + */ + if (new && (nhg_connected_tree_add(head, new) == NULL)) + return NULL; + + /* If it wasn't successful, it must be a duplicate. We enforce the + * unique property for the `nhg_connected` tree. + */ + nhg_connected_free(new); + + return depend; +} + +static void +nhg_connected_tree_decrement_ref(struct nhg_connected_tree_head *head) +{ + struct nhg_connected *rb_node_dep = NULL; + + frr_each_safe(nhg_connected_tree, head, rb_node_dep) { + zebra_nhg_decrement_ref(rb_node_dep->nhe); + } +} + +static void +nhg_connected_tree_increment_ref(struct nhg_connected_tree_head *head) +{ + struct nhg_connected *rb_node_dep = NULL; + + frr_each(nhg_connected_tree, head, rb_node_dep) { + zebra_nhg_increment_ref(rb_node_dep->nhe); + } +} + +struct nhg_hash_entry *zebra_nhg_resolve(struct nhg_hash_entry *nhe) +{ + if (CHECK_FLAG(nhe->flags, NEXTHOP_GROUP_RECURSIVE) + && !zebra_nhg_depends_is_empty(nhe)) { + nhe = nhg_connected_tree_root(&nhe->nhg_depends)->nhe; + return zebra_nhg_resolve(nhe); + } + + return nhe; +} + +unsigned int zebra_nhg_depends_count(const struct nhg_hash_entry *nhe) +{ + return nhg_connected_tree_count(&nhe->nhg_depends); +} + +bool zebra_nhg_depends_is_empty(const struct nhg_hash_entry *nhe) +{ + return nhg_connected_tree_is_empty(&nhe->nhg_depends); +} + +static void zebra_nhg_depends_del(struct nhg_hash_entry *from, + struct nhg_hash_entry *depend) +{ + nhg_connected_tree_del_nhe(&from->nhg_depends, depend); +} + +static void zebra_nhg_depends_init(struct nhg_hash_entry *nhe) +{ + nhg_connected_tree_init(&nhe->nhg_depends); +} + +unsigned int zebra_nhg_dependents_count(const struct nhg_hash_entry *nhe) +{ + return nhg_connected_tree_count(&nhe->nhg_dependents); +} + + +bool zebra_nhg_dependents_is_empty(const struct nhg_hash_entry *nhe) +{ + return nhg_connected_tree_is_empty(&nhe->nhg_dependents); +} + +static void zebra_nhg_dependents_del(struct nhg_hash_entry *from, + struct nhg_hash_entry *dependent) +{ + nhg_connected_tree_del_nhe(&from->nhg_dependents, dependent); +} + +static void zebra_nhg_dependents_add(struct nhg_hash_entry *to, + struct nhg_hash_entry *dependent) +{ + nhg_connected_tree_add_nhe(&to->nhg_dependents, dependent); +} + +static void zebra_nhg_dependents_init(struct nhg_hash_entry *nhe) +{ + nhg_connected_tree_init(&nhe->nhg_dependents); +} + +/* Release this nhe from anything depending on it */ +static void zebra_nhg_dependents_release(struct nhg_hash_entry *nhe) +{ + struct nhg_connected *rb_node_dep = NULL; + + frr_each_safe(nhg_connected_tree, &nhe->nhg_dependents, rb_node_dep) { + zebra_nhg_depends_del(rb_node_dep->nhe, nhe); + /* recheck validity of the dependent */ + zebra_nhg_check_valid(rb_node_dep->nhe); + } +} + +/* Release this nhe from anything that it depends on */ +static void zebra_nhg_depends_release(struct nhg_hash_entry *nhe) +{ + if (!zebra_nhg_depends_is_empty(nhe)) { + struct nhg_connected *rb_node_dep = NULL; + + frr_each_safe(nhg_connected_tree, &nhe->nhg_depends, + rb_node_dep) { + zebra_nhg_dependents_del(rb_node_dep->nhe, nhe); + } + } +} + + +struct nhg_hash_entry *zebra_nhg_lookup_id(uint32_t id) +{ + struct nhg_hash_entry lookup = {}; + + lookup.id = id; + return hash_lookup(zrouter.nhgs_id, &lookup); +} + +static int zebra_nhg_insert_id(struct nhg_hash_entry *nhe) +{ + if (hash_lookup(zrouter.nhgs_id, nhe)) { + flog_err( + EC_ZEBRA_NHG_TABLE_INSERT_FAILED, + "Failed inserting NHG %pNG into the ID hash table, entry already exists", + nhe); + return -1; + } + + (void)hash_get(zrouter.nhgs_id, nhe, hash_alloc_intern); + + return 0; +} + +static void zebra_nhg_set_if(struct nhg_hash_entry *nhe, struct interface *ifp) +{ + nhe->ifp = ifp; + if_nhg_dependents_add(ifp, nhe); +} + +static void +zebra_nhg_connect_depends(struct nhg_hash_entry *nhe, + struct nhg_connected_tree_head *nhg_depends) +{ + struct nhg_connected *rb_node_dep = NULL; + + /* This has been allocated higher above in the stack. Could probably + * re-allocate and free the old stuff but just using the same memory + * for now. Otherwise, their might be a time trade-off for repeated + * alloc/frees as startup. + */ + nhe->nhg_depends = *nhg_depends; + + /* Attach backpointer to anything that it depends on */ + zebra_nhg_dependents_init(nhe); + if (!zebra_nhg_depends_is_empty(nhe)) { + frr_each(nhg_connected_tree, &nhe->nhg_depends, rb_node_dep) { + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nhe %p (%pNG), dep %p (%pNG)", + __func__, nhe, nhe, rb_node_dep->nhe, + rb_node_dep->nhe); + + zebra_nhg_dependents_add(rb_node_dep->nhe, nhe); + } + } +} + +/* Init an nhe, for use in a hash lookup for example */ +void zebra_nhe_init(struct nhg_hash_entry *nhe, afi_t afi, + const struct nexthop *nh) +{ + memset(nhe, 0, sizeof(struct nhg_hash_entry)); + nhe->vrf_id = VRF_DEFAULT; + nhe->type = ZEBRA_ROUTE_NHG; + nhe->afi = AFI_UNSPEC; + + /* There are some special rules that apply to groups representing + * a single nexthop. + */ + if (nh && (nh->next == NULL)) { + switch (nh->type) { + case NEXTHOP_TYPE_IFINDEX: + case NEXTHOP_TYPE_BLACKHOLE: + /* + * This switch case handles setting the afi different + * for ipv4/v6 routes. Ifindex/blackhole nexthop + * objects cannot be ambiguous, they must be Address + * Family specific. If we get here, we will either use + * the AF of the route, or the one we got passed from + * here from the kernel. + */ + nhe->afi = afi; + break; + case NEXTHOP_TYPE_IPV4_IFINDEX: + case NEXTHOP_TYPE_IPV4: + nhe->afi = AFI_IP; + break; + case NEXTHOP_TYPE_IPV6_IFINDEX: + case NEXTHOP_TYPE_IPV6: + nhe->afi = AFI_IP6; + break; + } + } +} + +struct nhg_hash_entry *zebra_nhg_alloc(void) +{ + struct nhg_hash_entry *nhe; + + nhe = XCALLOC(MTYPE_NHG, sizeof(struct nhg_hash_entry)); + + return nhe; +} + +/* + * Allocate new nhe and make shallow copy of 'orig'; no + * recursive info is copied. + */ +struct nhg_hash_entry *zebra_nhe_copy(const struct nhg_hash_entry *orig, + uint32_t id) +{ + struct nhg_hash_entry *nhe; + + nhe = zebra_nhg_alloc(); + + nhe->id = id; + + nexthop_group_copy(&(nhe->nhg), &(orig->nhg)); + + nhe->vrf_id = orig->vrf_id; + nhe->afi = orig->afi; + nhe->type = orig->type ? orig->type : ZEBRA_ROUTE_NHG; + nhe->refcnt = 0; + nhe->dplane_ref = zebra_router_get_next_sequence(); + + /* Copy backup info also, if present */ + if (orig->backup_info) + nhe->backup_info = nhg_backup_copy(orig->backup_info); + + return nhe; +} + +/* Allocation via hash handler */ +static void *zebra_nhg_hash_alloc(void *arg) +{ + struct nhg_hash_entry *nhe = NULL; + struct nhg_hash_entry *copy = arg; + + nhe = zebra_nhe_copy(copy, copy->id); + + /* Mark duplicate nexthops in a group at creation time. */ + nexthop_group_mark_duplicates(&(nhe->nhg)); + + /* + * Add the ifp now if it's not a group or recursive and has ifindex. + * + * A proto-owned ID is always a group. + */ + if (!PROTO_OWNED(nhe) && nhe->nhg.nexthop && !nhe->nhg.nexthop->next + && !nhe->nhg.nexthop->resolved && nhe->nhg.nexthop->ifindex) { + struct interface *ifp = NULL; + + ifp = if_lookup_by_index(nhe->nhg.nexthop->ifindex, + nhe->nhg.nexthop->vrf_id); + if (ifp) + zebra_nhg_set_if(nhe, ifp); + else { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "Failed to lookup an interface with ifindex=%d in vrf=%u for NHE %pNG", + nhe->nhg.nexthop->ifindex, + nhe->nhg.nexthop->vrf_id, nhe); + } + } + + return nhe; +} + +uint32_t zebra_nhg_hash_key(const void *arg) +{ + const struct nhg_hash_entry *nhe = arg; + uint32_t key = 0x5a351234; + uint32_t primary = 0; + uint32_t backup = 0; + + primary = nexthop_group_hash(&(nhe->nhg)); + if (nhe->backup_info) + backup = nexthop_group_hash(&(nhe->backup_info->nhe->nhg)); + + key = jhash_3words(primary, backup, nhe->type, key); + + key = jhash_2words(nhe->vrf_id, nhe->afi, key); + + return key; +} + +uint32_t zebra_nhg_id_key(const void *arg) +{ + const struct nhg_hash_entry *nhe = arg; + + return nhe->id; +} + +/* Helper with common nhg/nhe nexthop comparison logic */ +static bool nhg_compare_nexthops(const struct nexthop *nh1, + const struct nexthop *nh2) +{ + assert(nh1 != NULL && nh2 != NULL); + + /* + * We have to check the active flag of each individual one, + * not just the overall active_num. This solves the special case + * issue of a route with a nexthop group with one nexthop + * resolving to itself and thus marking it inactive. If we + * have two different routes each wanting to mark a different + * nexthop inactive, they need to hash to two different groups. + * + * If we just hashed on num_active, they would hash the same + * which is incorrect. + * + * ex) + * 1.1.1.0/24 + * -> 1.1.1.1 dummy1 (inactive) + * -> 1.1.2.1 dummy2 + * + * 1.1.2.0/24 + * -> 1.1.1.1 dummy1 + * -> 1.1.2.1 dummy2 (inactive) + * + * Without checking each individual one, they would hash to + * the same group and both have 1.1.1.1 dummy1 marked inactive. + * + */ + if (CHECK_FLAG(nh1->flags, NEXTHOP_FLAG_ACTIVE) + != CHECK_FLAG(nh2->flags, NEXTHOP_FLAG_ACTIVE)) + return false; + + if (!nexthop_same(nh1, nh2)) + return false; + + return true; +} + +bool zebra_nhg_hash_equal(const void *arg1, const void *arg2) +{ + const struct nhg_hash_entry *nhe1 = arg1; + const struct nhg_hash_entry *nhe2 = arg2; + struct nexthop *nexthop1; + struct nexthop *nexthop2; + + /* No matter what if they equal IDs, assume equal */ + if (nhe1->id && nhe2->id && (nhe1->id == nhe2->id)) + return true; + + if (nhe1->type != nhe2->type) + return false; + + if (nhe1->vrf_id != nhe2->vrf_id) + return false; + + if (nhe1->afi != nhe2->afi) + return false; + + /* Nexthops should be in-order, so we simply compare them in-place */ + for (nexthop1 = nhe1->nhg.nexthop, nexthop2 = nhe2->nhg.nexthop; + nexthop1 && nexthop2; + nexthop1 = nexthop1->next, nexthop2 = nexthop2->next) { + + if (!nhg_compare_nexthops(nexthop1, nexthop2)) + return false; + } + + /* Check for unequal list lengths */ + if (nexthop1 || nexthop2) + return false; + + /* If there's no backup info, comparison is done. */ + if ((nhe1->backup_info == NULL) && (nhe2->backup_info == NULL)) + return true; + + /* Compare backup info also - test the easy things first */ + if (nhe1->backup_info && (nhe2->backup_info == NULL)) + return false; + if (nhe2->backup_info && (nhe1->backup_info == NULL)) + return false; + + /* Compare number of backups before actually comparing any */ + for (nexthop1 = nhe1->backup_info->nhe->nhg.nexthop, + nexthop2 = nhe2->backup_info->nhe->nhg.nexthop; + nexthop1 && nexthop2; + nexthop1 = nexthop1->next, nexthop2 = nexthop2->next) { + ; + } + + /* Did we find the end of one list before the other? */ + if (nexthop1 || nexthop2) + return false; + + /* Have to compare the backup nexthops */ + for (nexthop1 = nhe1->backup_info->nhe->nhg.nexthop, + nexthop2 = nhe2->backup_info->nhe->nhg.nexthop; + nexthop1 && nexthop2; + nexthop1 = nexthop1->next, nexthop2 = nexthop2->next) { + + if (!nhg_compare_nexthops(nexthop1, nexthop2)) + return false; + } + + return true; +} + +bool zebra_nhg_hash_id_equal(const void *arg1, const void *arg2) +{ + const struct nhg_hash_entry *nhe1 = arg1; + const struct nhg_hash_entry *nhe2 = arg2; + + return nhe1->id == nhe2->id; +} + +static int zebra_nhg_process_grp(struct nexthop_group *nhg, + struct nhg_connected_tree_head *depends, + struct nh_grp *grp, uint8_t count) +{ + nhg_connected_tree_init(depends); + + for (int i = 0; i < count; i++) { + struct nhg_hash_entry *depend = NULL; + /* We do not care about nexthop_grp.weight at + * this time. But we should figure out + * how to adapt this to our code in + * the future. + */ + depend = depends_find_id_add(depends, grp[i].id); + + if (!depend) { + flog_err( + EC_ZEBRA_NHG_SYNC, + "Received Nexthop Group from the kernel with a dependent Nexthop ID (%u) which we do not have in our table", + grp[i].id); + return -1; + } + + /* + * If this is a nexthop with its own group + * dependencies, add them as well. Not sure its + * even possible to have a group within a group + * in the kernel. + */ + + copy_nexthops(&nhg->nexthop, depend->nhg.nexthop, NULL); + } + + return 0; +} + +static void handle_recursive_depend(struct nhg_connected_tree_head *nhg_depends, + struct nexthop *nh, afi_t afi, int type) +{ + struct nhg_hash_entry *depend = NULL; + struct nexthop_group resolved_ng = {}; + + resolved_ng.nexthop = nh; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: head %p, nh %pNHv", + __func__, nhg_depends, nh); + + depend = zebra_nhg_rib_find(0, &resolved_ng, afi, type); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nh %pNHv => %p (%u)", + __func__, nh, depend, + depend ? depend->id : 0); + + if (depend) + depends_add(nhg_depends, depend); +} + +/* + * Lookup an nhe in the global hash, using data from another nhe. If 'lookup' + * has an id value, that's used. Create a new global/shared nhe if not found. + */ +static bool zebra_nhe_find(struct nhg_hash_entry **nhe, /* return value */ + struct nhg_hash_entry *lookup, + struct nhg_connected_tree_head *nhg_depends, + afi_t afi, bool from_dplane) +{ + bool created = false; + bool recursive = false; + struct nhg_hash_entry *newnhe, *backup_nhe; + struct nexthop *nh = NULL; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug( + "%s: id %u, lookup %p, vrf %d, type %d, depends %p%s", + __func__, lookup->id, lookup, lookup->vrf_id, + lookup->type, nhg_depends, + (from_dplane ? " (from dplane)" : "")); + + if (lookup->id) + (*nhe) = zebra_nhg_lookup_id(lookup->id); + else + (*nhe) = hash_lookup(zrouter.nhgs, lookup); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: lookup => %p (%pNG)", __func__, *nhe, *nhe); + + /* If we found an existing object, we're done */ + if (*nhe) + goto done; + + /* We're going to create/insert a new nhe: + * assign the next global id value if necessary. + */ + if (lookup->id == 0) + lookup->id = nhg_get_next_id(); + + if (!from_dplane && lookup->id < ZEBRA_NHG_PROTO_LOWER) { + /* + * This is a zebra hashed/owned NHG. + * + * It goes in HASH and ID table. + */ + newnhe = hash_get(zrouter.nhgs, lookup, zebra_nhg_hash_alloc); + zebra_nhg_insert_id(newnhe); + } else { + /* + * This is upperproto owned NHG or one we read in from dataplane + * and should not be hashed to. + * + * It goes in ID table. + */ + newnhe = + hash_get(zrouter.nhgs_id, lookup, zebra_nhg_hash_alloc); + } + + created = true; + + /* Mail back the new object */ + *nhe = newnhe; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: => created %p (%pNG)", __func__, newnhe, + newnhe); + + /* Only hash/lookup the depends if the first lookup + * fails to find something. This should hopefully save a + * lot of cycles for larger ecmp sizes. + */ + if (nhg_depends) { + /* If you don't want to hash on each nexthop in the + * nexthop group struct you can pass the depends + * directly. Kernel-side we do this since it just looks + * them up via IDs. + */ + zebra_nhg_connect_depends(newnhe, nhg_depends); + goto done; + } + + /* Prepare dependency relationships if this is not a + * singleton nexthop. There are two cases: a single + * recursive nexthop, where we need a relationship to the + * resolving nexthop; or a group of nexthops, where we need + * relationships with the corresponding singletons. + */ + zebra_nhg_depends_init(newnhe); + + nh = newnhe->nhg.nexthop; + + if (CHECK_FLAG(nh->flags, NEXTHOP_FLAG_ACTIVE)) + SET_FLAG(newnhe->flags, NEXTHOP_GROUP_VALID); + + if (nh->next == NULL && newnhe->id < ZEBRA_NHG_PROTO_LOWER) { + if (CHECK_FLAG(nh->flags, NEXTHOP_FLAG_RECURSIVE)) { + /* Single recursive nexthop */ + handle_recursive_depend(&newnhe->nhg_depends, + nh->resolved, afi, + newnhe->type); + recursive = true; + } + } else { + /* Proto-owned are groups by default */ + /* List of nexthops */ + for (nh = newnhe->nhg.nexthop; nh; nh = nh->next) { + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: depends NH %pNHv %s", + __func__, nh, + CHECK_FLAG(nh->flags, + NEXTHOP_FLAG_RECURSIVE) ? + "(R)" : ""); + + depends_find_add(&newnhe->nhg_depends, nh, afi, + newnhe->type, from_dplane); + } + } + + if (recursive) + SET_FLAG(newnhe->flags, NEXTHOP_GROUP_RECURSIVE); + + /* Attach dependent backpointers to singletons */ + zebra_nhg_connect_depends(newnhe, &newnhe->nhg_depends); + + /** + * Backup Nexthops + */ + + if (zebra_nhg_get_backup_nhg(newnhe) == NULL || + zebra_nhg_get_backup_nhg(newnhe)->nexthop == NULL) + goto done; + + /* If there are backup nexthops, add them to the backup + * depends tree. The rules here are a little different. + */ + recursive = false; + backup_nhe = newnhe->backup_info->nhe; + + nh = backup_nhe->nhg.nexthop; + + /* Singleton recursive NH */ + if (nh->next == NULL && + CHECK_FLAG(nh->flags, NEXTHOP_FLAG_RECURSIVE)) { + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: backup depend NH %pNHv (R)", + __func__, nh); + + /* Single recursive nexthop */ + handle_recursive_depend(&backup_nhe->nhg_depends, nh->resolved, + afi, backup_nhe->type); + recursive = true; + } else { + /* One or more backup NHs */ + for (; nh; nh = nh->next) { + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: backup depend NH %pNHv %s", + __func__, nh, + CHECK_FLAG(nh->flags, + NEXTHOP_FLAG_RECURSIVE) ? + "(R)" : ""); + + depends_find_add(&backup_nhe->nhg_depends, nh, afi, + backup_nhe->type, from_dplane); + } + } + + if (recursive) + SET_FLAG(backup_nhe->flags, NEXTHOP_GROUP_RECURSIVE); + +done: + /* Reset time since last update */ + (*nhe)->uptime = monotime(NULL); + + return created; +} + +/* + * Lookup or create an nhe, based on an nhg or an nhe id. + */ +static bool zebra_nhg_find(struct nhg_hash_entry **nhe, uint32_t id, + struct nexthop_group *nhg, + struct nhg_connected_tree_head *nhg_depends, + vrf_id_t vrf_id, afi_t afi, int type, + bool from_dplane) +{ + struct nhg_hash_entry lookup = {}; + bool created = false; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: id %u, nhg %p, vrf %d, type %d, depends %p", + __func__, id, nhg, vrf_id, type, + nhg_depends); + + /* Use a temporary nhe and call into the superset/common code */ + lookup.id = id; + lookup.type = type ? type : ZEBRA_ROUTE_NHG; + lookup.nhg = *nhg; + + lookup.vrf_id = vrf_id; + if (nhg_depends || lookup.nhg.nexthop->next) { + /* Groups can have all vrfs and AF's in them */ + lookup.afi = AFI_UNSPEC; + } else { + switch (lookup.nhg.nexthop->type) { + case (NEXTHOP_TYPE_IFINDEX): + case (NEXTHOP_TYPE_BLACKHOLE): + /* + * This switch case handles setting the afi different + * for ipv4/v6 routes. Ifindex/blackhole nexthop + * objects cannot be ambiguous, they must be Address + * Family specific. If we get here, we will either use + * the AF of the route, or the one we got passed from + * here from the kernel. + */ + lookup.afi = afi; + break; + case (NEXTHOP_TYPE_IPV4_IFINDEX): + case (NEXTHOP_TYPE_IPV4): + lookup.afi = AFI_IP; + break; + case (NEXTHOP_TYPE_IPV6_IFINDEX): + case (NEXTHOP_TYPE_IPV6): + lookup.afi = AFI_IP6; + break; + } + } + + created = zebra_nhe_find(nhe, &lookup, nhg_depends, afi, from_dplane); + + return created; +} + +/* Find/create a single nexthop */ +static struct nhg_hash_entry *zebra_nhg_find_nexthop(uint32_t id, + struct nexthop *nh, + afi_t afi, int type, + bool from_dplane) +{ + struct nhg_hash_entry *nhe = NULL; + struct nexthop_group nhg = {}; + vrf_id_t vrf_id = !vrf_is_backend_netns() ? VRF_DEFAULT : nh->vrf_id; + + nexthop_group_add_sorted(&nhg, nh); + + zebra_nhg_find(&nhe, id, &nhg, NULL, vrf_id, afi, type, from_dplane); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nh %pNHv => %p (%pNG)", __func__, nh, nhe, nhe); + + return nhe; +} + +static uint32_t nhg_ctx_get_id(const struct nhg_ctx *ctx) +{ + return ctx->id; +} + +static void nhg_ctx_set_status(struct nhg_ctx *ctx, enum nhg_ctx_status status) +{ + ctx->status = status; +} + +static enum nhg_ctx_status nhg_ctx_get_status(const struct nhg_ctx *ctx) +{ + return ctx->status; +} + +static void nhg_ctx_set_op(struct nhg_ctx *ctx, enum nhg_ctx_op_e op) +{ + ctx->op = op; +} + +static enum nhg_ctx_op_e nhg_ctx_get_op(const struct nhg_ctx *ctx) +{ + return ctx->op; +} + +static vrf_id_t nhg_ctx_get_vrf_id(const struct nhg_ctx *ctx) +{ + return ctx->vrf_id; +} + +static int nhg_ctx_get_type(const struct nhg_ctx *ctx) +{ + return ctx->type; +} + +static int nhg_ctx_get_afi(const struct nhg_ctx *ctx) +{ + return ctx->afi; +} + +static struct nexthop *nhg_ctx_get_nh(struct nhg_ctx *ctx) +{ + return &ctx->u.nh; +} + +static uint8_t nhg_ctx_get_count(const struct nhg_ctx *ctx) +{ + return ctx->count; +} + +static struct nh_grp *nhg_ctx_get_grp(struct nhg_ctx *ctx) +{ + return ctx->u.grp; +} + +static struct nhg_ctx *nhg_ctx_new(void) +{ + struct nhg_ctx *new; + + new = XCALLOC(MTYPE_NHG_CTX, sizeof(struct nhg_ctx)); + + return new; +} + +void nhg_ctx_free(struct nhg_ctx **ctx) +{ + struct nexthop *nh; + + if (ctx == NULL) + return; + + assert((*ctx) != NULL); + + if (nhg_ctx_get_count(*ctx)) + goto done; + + nh = nhg_ctx_get_nh(*ctx); + + nexthop_del_labels(nh); + nexthop_del_srv6_seg6local(nh); + nexthop_del_srv6_seg6(nh); + +done: + XFREE(MTYPE_NHG_CTX, *ctx); +} + +static struct nhg_ctx *nhg_ctx_init(uint32_t id, struct nexthop *nh, + struct nh_grp *grp, vrf_id_t vrf_id, + afi_t afi, int type, uint8_t count) +{ + struct nhg_ctx *ctx = NULL; + + ctx = nhg_ctx_new(); + + ctx->id = id; + ctx->vrf_id = vrf_id; + ctx->afi = afi; + ctx->type = type; + ctx->count = count; + + if (count) + /* Copy over the array */ + memcpy(&ctx->u.grp, grp, count * sizeof(struct nh_grp)); + else if (nh) + ctx->u.nh = *nh; + + return ctx; +} + +static void zebra_nhg_set_valid(struct nhg_hash_entry *nhe) +{ + struct nhg_connected *rb_node_dep; + + SET_FLAG(nhe->flags, NEXTHOP_GROUP_VALID); + + frr_each(nhg_connected_tree, &nhe->nhg_dependents, rb_node_dep) + zebra_nhg_set_valid(rb_node_dep->nhe); +} + +static void zebra_nhg_set_invalid(struct nhg_hash_entry *nhe) +{ + struct nhg_connected *rb_node_dep; + + UNSET_FLAG(nhe->flags, NEXTHOP_GROUP_VALID); + + /* If we're in shutdown, this interface event needs to clean + * up installed NHGs, so don't clear that flag directly. + */ + if (!zebra_router_in_shutdown()) + UNSET_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED); + + /* Update validity of nexthops depending on it */ + frr_each(nhg_connected_tree, &nhe->nhg_dependents, rb_node_dep) + zebra_nhg_check_valid(rb_node_dep->nhe); +} + +void zebra_nhg_check_valid(struct nhg_hash_entry *nhe) +{ + struct nhg_connected *rb_node_dep = NULL; + bool valid = false; + + /* If anthing else in the group is valid, the group is valid */ + frr_each(nhg_connected_tree, &nhe->nhg_depends, rb_node_dep) { + if (CHECK_FLAG(rb_node_dep->nhe->flags, NEXTHOP_GROUP_VALID)) { + valid = true; + goto done; + } + } + +done: + if (valid) + zebra_nhg_set_valid(nhe); + else + zebra_nhg_set_invalid(nhe); +} + +static void zebra_nhg_release_all_deps(struct nhg_hash_entry *nhe) +{ + /* Remove it from any lists it may be on */ + zebra_nhg_depends_release(nhe); + zebra_nhg_dependents_release(nhe); + if (nhe->ifp) + if_nhg_dependents_del(nhe->ifp, nhe); +} + +static void zebra_nhg_release(struct nhg_hash_entry *nhe) +{ + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nhe %p (%pNG)", __func__, nhe, nhe); + + zebra_nhg_release_all_deps(nhe); + + /* + * If its not zebra owned, we didn't store it here and have to be + * sure we don't clear one thats actually being used. + */ + if (nhe->id < ZEBRA_NHG_PROTO_LOWER) + hash_release(zrouter.nhgs, nhe); + + hash_release(zrouter.nhgs_id, nhe); +} + +static void zebra_nhg_handle_uninstall(struct nhg_hash_entry *nhe) +{ + zebra_nhg_release(nhe); + zebra_nhg_free(nhe); +} + +static void zebra_nhg_handle_install(struct nhg_hash_entry *nhe) +{ + /* Update validity of groups depending on it */ + struct nhg_connected *rb_node_dep; + + frr_each_safe(nhg_connected_tree, &nhe->nhg_dependents, rb_node_dep) + zebra_nhg_set_valid(rb_node_dep->nhe); +} + +/* + * The kernel/other program has changed the state of a nexthop object we are + * using. + */ +static void zebra_nhg_handle_kernel_state_change(struct nhg_hash_entry *nhe, + bool is_delete) +{ + if (nhe->refcnt) { + flog_err( + EC_ZEBRA_NHG_SYNC, + "Kernel %s a nexthop group with ID (%pNG) that we are still using for a route, sending it back down", + (is_delete ? "deleted" : "updated"), nhe); + + UNSET_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED); + zebra_nhg_install_kernel(nhe); + } else + zebra_nhg_handle_uninstall(nhe); +} + +static int nhg_ctx_process_new(struct nhg_ctx *ctx) +{ + struct nexthop_group *nhg = NULL; + struct nhg_connected_tree_head nhg_depends = {}; + struct nhg_hash_entry *lookup = NULL; + struct nhg_hash_entry *nhe = NULL; + + uint32_t id = nhg_ctx_get_id(ctx); + uint8_t count = nhg_ctx_get_count(ctx); + vrf_id_t vrf_id = nhg_ctx_get_vrf_id(ctx); + int type = nhg_ctx_get_type(ctx); + afi_t afi = nhg_ctx_get_afi(ctx); + + lookup = zebra_nhg_lookup_id(id); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: id %u, count %d, lookup => %p", + __func__, id, count, lookup); + + if (lookup) { + /* This is already present in our table, hence an update + * that we did not initate. + */ + zebra_nhg_handle_kernel_state_change(lookup, false); + return 0; + } + + if (nhg_ctx_get_count(ctx)) { + nhg = nexthop_group_new(); + if (zebra_nhg_process_grp(nhg, &nhg_depends, + nhg_ctx_get_grp(ctx), count)) { + depends_decrement_free(&nhg_depends); + nexthop_group_delete(&nhg); + return -ENOENT; + } + + if (!zebra_nhg_find(&nhe, id, nhg, &nhg_depends, vrf_id, afi, + type, true)) + depends_decrement_free(&nhg_depends); + + /* These got copied over in zebra_nhg_alloc() */ + nexthop_group_delete(&nhg); + } else + nhe = zebra_nhg_find_nexthop(id, nhg_ctx_get_nh(ctx), afi, type, + true); + + if (!nhe) { + flog_err( + EC_ZEBRA_TABLE_LOOKUP_FAILED, + "Zebra failed to find or create a nexthop hash entry for ID (%u)", + id); + return -1; + } + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nhe %p (%pNG) is new", __func__, nhe, nhe); + + /* + * If daemon nhg from the kernel, add a refcnt here to indicate the + * daemon owns it. + */ + if (PROTO_OWNED(nhe)) + zebra_nhg_increment_ref(nhe); + + SET_FLAG(nhe->flags, NEXTHOP_GROUP_VALID); + SET_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED); + + return 0; +} + +static int nhg_ctx_process_del(struct nhg_ctx *ctx) +{ + struct nhg_hash_entry *nhe = NULL; + uint32_t id = nhg_ctx_get_id(ctx); + + nhe = zebra_nhg_lookup_id(id); + + if (!nhe) { + flog_warn( + EC_ZEBRA_BAD_NHG_MESSAGE, + "Kernel delete message received for nexthop group ID (%u) that we do not have in our ID table", + id); + return -1; + } + + zebra_nhg_handle_kernel_state_change(nhe, true); + + return 0; +} + +static void nhg_ctx_fini(struct nhg_ctx **ctx) +{ + /* + * Just freeing for now, maybe do something more in the future + * based on flag. + */ + + nhg_ctx_free(ctx); +} + +static int queue_add(struct nhg_ctx *ctx) +{ + /* If its queued or already processed do nothing */ + if (nhg_ctx_get_status(ctx) == NHG_CTX_QUEUED) + return 0; + + if (rib_queue_nhg_ctx_add(ctx)) { + nhg_ctx_set_status(ctx, NHG_CTX_FAILURE); + return -1; + } + + nhg_ctx_set_status(ctx, NHG_CTX_QUEUED); + + return 0; +} + +int nhg_ctx_process(struct nhg_ctx *ctx) +{ + int ret = 0; + + switch (nhg_ctx_get_op(ctx)) { + case NHG_CTX_OP_NEW: + ret = nhg_ctx_process_new(ctx); + if (nhg_ctx_get_count(ctx) && ret == -ENOENT + && nhg_ctx_get_status(ctx) != NHG_CTX_REQUEUED) { + /** + * We have entered a situation where we are + * processing a group from the kernel + * that has a contained nexthop which + * we have not yet processed. + * + * Re-enqueue this ctx to be handled exactly one + * more time (indicated by the flag). + * + * By the time we get back to it, we + * should have processed its depends. + */ + nhg_ctx_set_status(ctx, NHG_CTX_NONE); + if (queue_add(ctx) == 0) { + nhg_ctx_set_status(ctx, NHG_CTX_REQUEUED); + return 0; + } + } + break; + case NHG_CTX_OP_DEL: + ret = nhg_ctx_process_del(ctx); + case NHG_CTX_OP_NONE: + break; + } + + nhg_ctx_set_status(ctx, (ret ? NHG_CTX_FAILURE : NHG_CTX_SUCCESS)); + + nhg_ctx_fini(&ctx); + + return ret; +} + +/* Kernel-side, you either get a single new nexthop or a array of ID's */ +int zebra_nhg_kernel_find(uint32_t id, struct nexthop *nh, struct nh_grp *grp, + uint8_t count, vrf_id_t vrf_id, afi_t afi, int type, + int startup) +{ + struct nhg_ctx *ctx = NULL; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nh %pNHv, id %u, count %d", + __func__, nh, id, (int)count); + + if (id > id_counter && id < ZEBRA_NHG_PROTO_LOWER) + /* Increase our counter so we don't try to create + * an ID that already exists + */ + id_counter = id; + + ctx = nhg_ctx_init(id, nh, grp, vrf_id, afi, type, count); + nhg_ctx_set_op(ctx, NHG_CTX_OP_NEW); + + /* Under statup conditions, we need to handle them immediately + * like we do for routes. Otherwise, we are going to get a route + * with a nhe_id that we have not handled. + */ + if (startup) + return nhg_ctx_process(ctx); + + if (queue_add(ctx)) { + nhg_ctx_fini(&ctx); + return -1; + } + + return 0; +} + +/* Kernel-side, received delete message */ +int zebra_nhg_kernel_del(uint32_t id, vrf_id_t vrf_id) +{ + struct nhg_ctx *ctx = NULL; + + ctx = nhg_ctx_init(id, NULL, NULL, vrf_id, 0, 0, 0); + + nhg_ctx_set_op(ctx, NHG_CTX_OP_DEL); + + if (queue_add(ctx)) { + nhg_ctx_fini(&ctx); + return -1; + } + + return 0; +} + +/* Some dependency helper functions */ +static struct nhg_hash_entry *depends_find_recursive(const struct nexthop *nh, + afi_t afi, int type) +{ + struct nhg_hash_entry *nhe; + struct nexthop *lookup = NULL; + + lookup = nexthop_dup(nh, NULL); + + nhe = zebra_nhg_find_nexthop(0, lookup, afi, type, false); + + nexthops_free(lookup); + + return nhe; +} + +static struct nhg_hash_entry *depends_find_singleton(const struct nexthop *nh, + afi_t afi, int type, + bool from_dplane) +{ + struct nhg_hash_entry *nhe; + struct nexthop lookup = {}; + + /* Capture a snapshot of this single nh; it might be part of a list, + * so we need to make a standalone copy. + */ + nexthop_copy_no_recurse(&lookup, nh, NULL); + + nhe = zebra_nhg_find_nexthop(0, &lookup, afi, type, from_dplane); + + /* The copy may have allocated labels; free them if necessary. */ + nexthop_del_labels(&lookup); + nexthop_del_srv6_seg6local(&lookup); + nexthop_del_srv6_seg6(&lookup); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nh %pNHv => %p (%pNG)", __func__, nh, nhe, nhe); + + return nhe; +} + +static struct nhg_hash_entry *depends_find(const struct nexthop *nh, afi_t afi, + int type, bool from_dplane) +{ + struct nhg_hash_entry *nhe = NULL; + + if (!nh) + goto done; + + /* We are separating these functions out to increase handling speed + * in the non-recursive case (by not alloc/freeing) + */ + if (CHECK_FLAG(nh->flags, NEXTHOP_FLAG_RECURSIVE)) + nhe = depends_find_recursive(nh, afi, type); + else + nhe = depends_find_singleton(nh, afi, type, from_dplane); + + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) { + zlog_debug("%s: nh %pNHv %s => %p (%pNG)", __func__, nh, + CHECK_FLAG(nh->flags, NEXTHOP_FLAG_RECURSIVE) ? "(R)" + : "", + nhe, nhe); + } + +done: + return nhe; +} + +static void depends_add(struct nhg_connected_tree_head *head, + struct nhg_hash_entry *depend) +{ + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: head %p nh %pNHv", + __func__, head, depend->nhg.nexthop); + + /* If NULL is returned, it was successfully added and + * needs to have its refcnt incremented. + * + * Else the NHE is already present in the tree and doesn't + * need to increment the refcnt. + */ + if (nhg_connected_tree_add_nhe(head, depend) == NULL) + zebra_nhg_increment_ref(depend); +} + +static struct nhg_hash_entry * +depends_find_add(struct nhg_connected_tree_head *head, struct nexthop *nh, + afi_t afi, int type, bool from_dplane) +{ + struct nhg_hash_entry *depend = NULL; + + depend = depends_find(nh, afi, type, from_dplane); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nh %pNHv => %p", + __func__, nh, depend); + + if (depend) + depends_add(head, depend); + + return depend; +} + +static struct nhg_hash_entry * +depends_find_id_add(struct nhg_connected_tree_head *head, uint32_t id) +{ + struct nhg_hash_entry *depend = NULL; + + depend = zebra_nhg_lookup_id(id); + + if (depend) + depends_add(head, depend); + + return depend; +} + +static void depends_decrement_free(struct nhg_connected_tree_head *head) +{ + nhg_connected_tree_decrement_ref(head); + nhg_connected_tree_free(head); +} + +/* Find an nhe based on a list of nexthops */ +struct nhg_hash_entry *zebra_nhg_rib_find(uint32_t id, + struct nexthop_group *nhg, + afi_t rt_afi, int type) +{ + struct nhg_hash_entry *nhe = NULL; + vrf_id_t vrf_id; + + /* + * CLANG SA is complaining that nexthop may be NULL + * Make it happy but this is ridonc + */ + assert(nhg->nexthop); + vrf_id = !vrf_is_backend_netns() ? VRF_DEFAULT : nhg->nexthop->vrf_id; + + zebra_nhg_find(&nhe, id, nhg, NULL, vrf_id, rt_afi, type, false); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: => nhe %p (%pNG)", __func__, nhe, nhe); + + return nhe; +} + +/* Find an nhe based on a route's nhe */ +struct nhg_hash_entry * +zebra_nhg_rib_find_nhe(struct nhg_hash_entry *rt_nhe, afi_t rt_afi) +{ + struct nhg_hash_entry *nhe = NULL; + + if (!(rt_nhe && rt_nhe->nhg.nexthop)) { + flog_err(EC_ZEBRA_TABLE_LOOKUP_FAILED, + "No nexthop passed to %s", __func__); + return NULL; + } + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: rt_nhe %p (%pNG)", __func__, rt_nhe, rt_nhe); + + zebra_nhe_find(&nhe, rt_nhe, NULL, rt_afi, false); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: => nhe %p (%pNG)", __func__, nhe, nhe); + + return nhe; +} + +/* + * Allocate backup nexthop info object. Typically these are embedded in + * nhg_hash_entry objects. + */ +struct nhg_backup_info *zebra_nhg_backup_alloc(void) +{ + struct nhg_backup_info *p; + + p = XCALLOC(MTYPE_NHG, sizeof(struct nhg_backup_info)); + + p->nhe = zebra_nhg_alloc(); + + /* Identify the embedded group used to hold the list of backups */ + SET_FLAG(p->nhe->flags, NEXTHOP_GROUP_BACKUP); + + return p; +} + +/* + * Free backup nexthop info object, deal with any embedded allocations + */ +void zebra_nhg_backup_free(struct nhg_backup_info **p) +{ + if (p && *p) { + if ((*p)->nhe) + zebra_nhg_free((*p)->nhe); + + XFREE(MTYPE_NHG, (*p)); + } +} + +/* Accessor for backup nexthop group */ +struct nexthop_group *zebra_nhg_get_backup_nhg(struct nhg_hash_entry *nhe) +{ + struct nexthop_group *p = NULL; + + if (nhe) { + if (nhe->backup_info && nhe->backup_info->nhe) + p = &(nhe->backup_info->nhe->nhg); + } + + return p; +} + +/* + * Helper to return a copy of a backup_info - note that this is a shallow + * copy, meant to be used when creating a new nhe from info passed in with + * a route e.g. + */ +static struct nhg_backup_info * +nhg_backup_copy(const struct nhg_backup_info *orig) +{ + struct nhg_backup_info *b; + + b = zebra_nhg_backup_alloc(); + + /* Copy list of nexthops */ + nexthop_group_copy(&(b->nhe->nhg), &(orig->nhe->nhg)); + + return b; +} + +static void zebra_nhg_free_members(struct nhg_hash_entry *nhe) +{ + nexthops_free(nhe->nhg.nexthop); + + zebra_nhg_backup_free(&nhe->backup_info); + + /* Decrement to remove connection ref */ + nhg_connected_tree_decrement_ref(&nhe->nhg_depends); + nhg_connected_tree_free(&nhe->nhg_depends); + nhg_connected_tree_free(&nhe->nhg_dependents); +} + +void zebra_nhg_free(struct nhg_hash_entry *nhe) +{ + if (IS_ZEBRA_DEBUG_NHG_DETAIL) { + /* Group or singleton? */ + if (nhe->nhg.nexthop && nhe->nhg.nexthop->next) + zlog_debug("%s: nhe %p (%pNG), refcnt %d", __func__, + nhe, nhe, nhe->refcnt); + else + zlog_debug("%s: nhe %p (%pNG), refcnt %d, NH %pNHv", + __func__, nhe, nhe, nhe->refcnt, + nhe->nhg.nexthop); + } + + THREAD_OFF(nhe->timer); + + zebra_nhg_free_members(nhe); + + XFREE(MTYPE_NHG, nhe); +} + +/* + * Let's just drop the memory associated with each item + */ +void zebra_nhg_hash_free(void *p) +{ + struct nhg_hash_entry *nhe = p; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) { + /* Group or singleton? */ + if (nhe->nhg.nexthop && nhe->nhg.nexthop->next) + zlog_debug("%s: nhe %p (%u), refcnt %d", __func__, nhe, + nhe->id, nhe->refcnt); + else + zlog_debug("%s: nhe %p (%pNG), refcnt %d, NH %pNHv", + __func__, nhe, nhe, nhe->refcnt, + nhe->nhg.nexthop); + } + + THREAD_OFF(nhe->timer); + + nexthops_free(nhe->nhg.nexthop); + + XFREE(MTYPE_NHG, nhe); +} + +/* + * On cleanup there are nexthop groups that have not + * been resolved at all( a nhe->id of 0 ). As such + * zebra needs to clean up the memory associated with + * those entries. + */ +void zebra_nhg_hash_free_zero_id(struct hash_bucket *b, void *arg) +{ + struct nhg_hash_entry *nhe = b->data; + struct nhg_connected *dep; + + while ((dep = nhg_connected_tree_pop(&nhe->nhg_depends))) { + if (dep->nhe->id == 0) + zebra_nhg_hash_free(dep->nhe); + + nhg_connected_free(dep); + } + + while ((dep = nhg_connected_tree_pop(&nhe->nhg_dependents))) + nhg_connected_free(dep); + + if (nhe->backup_info && nhe->backup_info->nhe->id == 0) { + while ((dep = nhg_connected_tree_pop( + &nhe->backup_info->nhe->nhg_depends))) + nhg_connected_free(dep); + + zebra_nhg_hash_free(nhe->backup_info->nhe); + + XFREE(MTYPE_NHG, nhe->backup_info); + } +} + +static void zebra_nhg_timer(struct thread *thread) +{ + struct nhg_hash_entry *nhe = THREAD_ARG(thread); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("Nexthop Timer for nhe: %pNG", nhe); + + if (nhe->refcnt == 1) + zebra_nhg_decrement_ref(nhe); +} + +void zebra_nhg_decrement_ref(struct nhg_hash_entry *nhe) +{ + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nhe %p (%pNG) %d => %d", __func__, nhe, nhe, + nhe->refcnt, nhe->refcnt - 1); + + nhe->refcnt--; + + if (!zebra_router_in_shutdown() && nhe->refcnt <= 0 && + CHECK_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED) && + !CHECK_FLAG(nhe->flags, NEXTHOP_GROUP_KEEP_AROUND)) { + nhe->refcnt = 1; + SET_FLAG(nhe->flags, NEXTHOP_GROUP_KEEP_AROUND); + thread_add_timer(zrouter.master, zebra_nhg_timer, nhe, + zrouter.nhg_keep, &nhe->timer); + return; + } + + if (!zebra_nhg_depends_is_empty(nhe)) + nhg_connected_tree_decrement_ref(&nhe->nhg_depends); + + if (ZEBRA_NHG_CREATED(nhe) && nhe->refcnt <= 0) + zebra_nhg_uninstall_kernel(nhe); +} + +void zebra_nhg_increment_ref(struct nhg_hash_entry *nhe) +{ + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: nhe %p (%pNG) %d => %d", __func__, nhe, nhe, + nhe->refcnt, nhe->refcnt + 1); + + nhe->refcnt++; + + if (thread_is_scheduled(nhe->timer)) { + THREAD_OFF(nhe->timer); + nhe->refcnt--; + UNSET_FLAG(nhe->flags, NEXTHOP_GROUP_KEEP_AROUND); + } + + if (!zebra_nhg_depends_is_empty(nhe)) + nhg_connected_tree_increment_ref(&nhe->nhg_depends); +} + +static struct nexthop *nexthop_set_resolved(afi_t afi, + const struct nexthop *newhop, + struct nexthop *nexthop, + struct zebra_sr_policy *policy) +{ + struct nexthop *resolved_hop; + uint8_t num_labels = 0; + mpls_label_t labels[MPLS_MAX_LABELS]; + enum lsp_types_t label_type = ZEBRA_LSP_NONE; + int i = 0; + + resolved_hop = nexthop_new(); + SET_FLAG(resolved_hop->flags, NEXTHOP_FLAG_ACTIVE); + + resolved_hop->vrf_id = nexthop->vrf_id; + switch (newhop->type) { + case NEXTHOP_TYPE_IPV4: + case NEXTHOP_TYPE_IPV4_IFINDEX: + /* If the resolving route specifies a gateway, use it */ + resolved_hop->type = newhop->type; + resolved_hop->gate.ipv4 = newhop->gate.ipv4; + + if (newhop->ifindex) { + resolved_hop->type = NEXTHOP_TYPE_IPV4_IFINDEX; + resolved_hop->ifindex = newhop->ifindex; + } + break; + case NEXTHOP_TYPE_IPV6: + case NEXTHOP_TYPE_IPV6_IFINDEX: + resolved_hop->type = newhop->type; + resolved_hop->gate.ipv6 = newhop->gate.ipv6; + + if (newhop->ifindex) { + resolved_hop->type = NEXTHOP_TYPE_IPV6_IFINDEX; + resolved_hop->ifindex = newhop->ifindex; + } + break; + case NEXTHOP_TYPE_IFINDEX: + /* If the resolving route is an interface route, + * it means the gateway we are looking up is connected + * to that interface. (The actual network is _not_ onlink). + * Therefore, the resolved route should have the original + * gateway as nexthop as it is directly connected. + * + * On Linux, we have to set the onlink netlink flag because + * otherwise, the kernel won't accept the route. + */ + resolved_hop->flags |= NEXTHOP_FLAG_ONLINK; + if (afi == AFI_IP) { + resolved_hop->type = NEXTHOP_TYPE_IPV4_IFINDEX; + resolved_hop->gate.ipv4 = nexthop->gate.ipv4; + } else if (afi == AFI_IP6) { + resolved_hop->type = NEXTHOP_TYPE_IPV6_IFINDEX; + resolved_hop->gate.ipv6 = nexthop->gate.ipv6; + } + resolved_hop->ifindex = newhop->ifindex; + break; + case NEXTHOP_TYPE_BLACKHOLE: + resolved_hop->type = NEXTHOP_TYPE_BLACKHOLE; + resolved_hop->bh_type = newhop->bh_type; + break; + } + + if (newhop->flags & NEXTHOP_FLAG_ONLINK) + resolved_hop->flags |= NEXTHOP_FLAG_ONLINK; + + /* Copy labels of the resolved route and the parent resolving to it */ + if (policy) { + int i = 0; + + /* + * Don't push the first SID if the corresponding action in the + * LFIB is POP. + */ + if (!newhop->nh_label || !newhop->nh_label->num_labels + || newhop->nh_label->label[0] == MPLS_LABEL_IMPLICIT_NULL) + i = 1; + + for (; i < policy->segment_list.label_num; i++) + labels[num_labels++] = policy->segment_list.labels[i]; + label_type = policy->segment_list.type; + } else if (newhop->nh_label) { + for (i = 0; i < newhop->nh_label->num_labels; i++) { + /* Be a bit picky about overrunning the local array */ + if (num_labels >= MPLS_MAX_LABELS) { + if (IS_ZEBRA_DEBUG_NHG || IS_ZEBRA_DEBUG_RIB) + zlog_debug("%s: too many labels in newhop %pNHv", + __func__, newhop); + break; + } + labels[num_labels++] = newhop->nh_label->label[i]; + } + /* Use the "outer" type */ + label_type = newhop->nh_label_type; + } + + if (nexthop->nh_label) { + for (i = 0; i < nexthop->nh_label->num_labels; i++) { + /* Be a bit picky about overrunning the local array */ + if (num_labels >= MPLS_MAX_LABELS) { + if (IS_ZEBRA_DEBUG_NHG || IS_ZEBRA_DEBUG_RIB) + zlog_debug("%s: too many labels in nexthop %pNHv", + __func__, nexthop); + break; + } + labels[num_labels++] = nexthop->nh_label->label[i]; + } + + /* If the parent has labels, use its type if + * we don't already have one. + */ + if (label_type == ZEBRA_LSP_NONE) + label_type = nexthop->nh_label_type; + } + + if (num_labels) + nexthop_add_labels(resolved_hop, label_type, num_labels, + labels); + + if (nexthop->nh_srv6) { + nexthop_add_srv6_seg6local(resolved_hop, + nexthop->nh_srv6->seg6local_action, + &nexthop->nh_srv6->seg6local_ctx); + nexthop_add_srv6_seg6(resolved_hop, + &nexthop->nh_srv6->seg6_segs); + } + + resolved_hop->rparent = nexthop; + _nexthop_add(&nexthop->resolved, resolved_hop); + + return resolved_hop; +} + +/* Checks if nexthop we are trying to resolve to is valid */ +static bool nexthop_valid_resolve(const struct nexthop *nexthop, + const struct nexthop *resolved) +{ + /* Can't resolve to a recursive nexthop */ + if (CHECK_FLAG(resolved->flags, NEXTHOP_FLAG_RECURSIVE)) + return false; + + /* Must be ACTIVE */ + if (!CHECK_FLAG(resolved->flags, NEXTHOP_FLAG_ACTIVE)) + return false; + + /* Must not be duplicate */ + if (CHECK_FLAG(resolved->flags, NEXTHOP_FLAG_DUPLICATE)) + return false; + + switch (nexthop->type) { + case NEXTHOP_TYPE_IPV4_IFINDEX: + case NEXTHOP_TYPE_IPV6_IFINDEX: + /* If the nexthop we are resolving to does not match the + * ifindex for the nexthop the route wanted, its not valid. + */ + if (nexthop->ifindex != resolved->ifindex) + return false; + break; + case NEXTHOP_TYPE_IPV4: + case NEXTHOP_TYPE_IPV6: + case NEXTHOP_TYPE_IFINDEX: + case NEXTHOP_TYPE_BLACKHOLE: + break; + } + + return true; +} + +/* + * When resolving a recursive nexthop, capture backup nexthop(s) also + * so they can be conveyed through the dataplane to the FIB. We'll look + * at the backups in the resolving nh 'nexthop' and its nhe, and copy them + * into the route's resolved nh 'resolved' and its nhe 'nhe'. + */ +static int resolve_backup_nexthops(const struct nexthop *nexthop, + const struct nhg_hash_entry *nhe, + struct nexthop *resolved, + struct nhg_hash_entry *resolve_nhe, + struct backup_nh_map_s *map) +{ + int i, j, idx; + const struct nexthop *bnh; + struct nexthop *nh, *newnh; + mpls_label_t labels[MPLS_MAX_LABELS]; + uint8_t num_labels; + + assert(nexthop->backup_num <= NEXTHOP_MAX_BACKUPS); + + /* Locate backups from the original nexthop's backup index and nhe */ + for (i = 0; i < nexthop->backup_num; i++) { + idx = nexthop->backup_idx[i]; + + /* Do we already know about this particular backup? */ + for (j = 0; j < map->map_count; j++) { + if (map->map[j].orig_idx == idx) + break; + } + + if (j < map->map_count) { + resolved->backup_idx[resolved->backup_num] = + map->map[j].new_idx; + resolved->backup_num++; + + SET_FLAG(resolved->flags, NEXTHOP_FLAG_HAS_BACKUP); + + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug("%s: found map idx orig %d, new %d", + __func__, map->map[j].orig_idx, + map->map[j].new_idx); + + continue; + } + + /* We can't handle any new map entries at this point. */ + if (map->map_count == MULTIPATH_NUM) + break; + + /* Need to create/copy a new backup */ + bnh = nhe->backup_info->nhe->nhg.nexthop; + for (j = 0; j < idx; j++) { + if (bnh == NULL) + break; + bnh = bnh->next; + } + + /* Whoops - bad index in the nexthop? */ + if (bnh == NULL) + continue; + + if (resolve_nhe->backup_info == NULL) + resolve_nhe->backup_info = zebra_nhg_backup_alloc(); + + /* Update backup info in the resolving nexthop and its nhe */ + newnh = nexthop_dup_no_recurse(bnh, NULL); + + /* We may need some special handling for mpls labels: the new + * backup needs to carry the recursive nexthop's labels, + * if any: they may be vrf labels e.g. + * The original/inner labels are in the stack of 'resolve_nhe', + * if that is longer than the stack in 'nexthop'. + */ + if (newnh->nh_label && resolved->nh_label && + nexthop->nh_label) { + if (resolved->nh_label->num_labels > + nexthop->nh_label->num_labels) { + /* Prepare new label stack */ + num_labels = 0; + for (j = 0; j < newnh->nh_label->num_labels; + j++) { + labels[j] = newnh->nh_label->label[j]; + num_labels++; + } + + /* Include inner labels */ + for (j = nexthop->nh_label->num_labels; + j < resolved->nh_label->num_labels; + j++) { + labels[num_labels] = + resolved->nh_label->label[j]; + num_labels++; + } + + /* Replace existing label stack in the backup */ + nexthop_del_labels(newnh); + nexthop_add_labels(newnh, bnh->nh_label_type, + num_labels, labels); + } + } + + /* Need to compute the new backup index in the new + * backup list, and add to map struct. + */ + j = 0; + nh = resolve_nhe->backup_info->nhe->nhg.nexthop; + if (nh) { + while (nh->next) { + nh = nh->next; + j++; + } + + nh->next = newnh; + j++; + + } else /* First one */ + resolve_nhe->backup_info->nhe->nhg.nexthop = newnh; + + /* Capture index */ + resolved->backup_idx[resolved->backup_num] = j; + resolved->backup_num++; + + SET_FLAG(resolved->flags, NEXTHOP_FLAG_HAS_BACKUP); + + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug("%s: added idx orig %d, new %d", + __func__, idx, j); + + /* Update map/cache */ + map->map[map->map_count].orig_idx = idx; + map->map[map->map_count].new_idx = j; + map->map_count++; + } + + return 0; +} + +/* + * So this nexthop resolution has decided that a connected route + * is the correct choice. At this point in time if FRR has multiple + * connected routes that all point to the same prefix one will be + * selected, *but* the particular interface may not be the one + * that the nexthop points at. Let's look at all the available + * connected routes on this node and if any of them auto match + * the routes nexthops ifindex that is good enough for a match + * + * This code is depending on the fact that a nexthop->ifindex is 0 + * if it is not known, if this assumption changes, yummy! + * Additionally a ifindx of 0 means figure it out for us. + */ +static struct route_entry * +zebra_nhg_connected_ifindex(struct route_node *rn, struct route_entry *match, + int32_t curr_ifindex) +{ + struct nexthop *newhop = match->nhe->nhg.nexthop; + struct route_entry *re; + + assert(newhop); /* What a kick in the patooey */ + + if (curr_ifindex == 0) + return match; + + if (curr_ifindex == newhop->ifindex) + return match; + + /* + * At this point we know that this route is matching a connected + * but there are possibly a bunch of connected routes that are + * alive that should be considered as well. So let's iterate over + * all the re's and see if they are connected as well and maybe one + * of those ifindexes match as well. + */ + RNODE_FOREACH_RE (rn, re) { + if (re->type != ZEBRA_ROUTE_CONNECT) + continue; + + if (CHECK_FLAG(re->status, ROUTE_ENTRY_REMOVED)) + continue; + + /* + * zebra has a connected route that is not removed + * let's test if it is good + */ + newhop = re->nhe->nhg.nexthop; + assert(newhop); + if (curr_ifindex == newhop->ifindex) + return re; + } + + return match; +} + +/* + * Given a nexthop we need to properly recursively resolve, + * do a table lookup to find and match if at all possible. + * Set the nexthop->ifindex and resolution info as appropriate. + */ +static int nexthop_active(struct nexthop *nexthop, struct nhg_hash_entry *nhe, + const struct prefix *top, int type, uint32_t flags, + uint32_t *pmtu, vrf_id_t vrf_id) +{ + struct prefix p; + struct route_table *table; + struct route_node *rn; + struct route_entry *match = NULL; + int resolved; + struct zebra_nhlfe *nhlfe; + struct nexthop *newhop; + struct interface *ifp; + rib_dest_t *dest; + struct zebra_vrf *zvrf; + struct in_addr local_ipv4; + struct in_addr *ipv4; + afi_t afi = AFI_IP; + + /* Reset some nexthop attributes that we'll recompute if necessary */ + if ((nexthop->type == NEXTHOP_TYPE_IPV4) + || (nexthop->type == NEXTHOP_TYPE_IPV6)) + nexthop->ifindex = 0; + + UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_RECURSIVE); + nexthops_free(nexthop->resolved); + nexthop->resolved = NULL; + + /* + * Set afi based on nexthop type. + * Some nexthop types get special handling, possibly skipping + * the normal processing. + */ + switch (nexthop->type) { + case NEXTHOP_TYPE_IFINDEX: + + ifp = if_lookup_by_index(nexthop->ifindex, nexthop->vrf_id); + /* + * If the interface exists and its operative or its a kernel + * route and interface is up, its active. We trust kernel routes + * to be good. + */ + if (ifp && (if_is_operative(ifp))) + return 1; + else + return 0; + break; + + case NEXTHOP_TYPE_IPV6_IFINDEX: + afi = AFI_IP6; + + if (IN6_IS_ADDR_LINKLOCAL(&nexthop->gate.ipv6)) { + ifp = if_lookup_by_index(nexthop->ifindex, + nexthop->vrf_id); + if (ifp && if_is_operative(ifp)) + return 1; + else + return 0; + } + break; + + case NEXTHOP_TYPE_IPV4: + case NEXTHOP_TYPE_IPV4_IFINDEX: + afi = AFI_IP; + break; + case NEXTHOP_TYPE_IPV6: + afi = AFI_IP6; + break; + + case NEXTHOP_TYPE_BLACKHOLE: + return 1; + } + + /* + * If the nexthop has been marked as 'onlink' we just need to make + * sure the nexthop's interface is known and is operational. + */ + if (CHECK_FLAG(nexthop->flags, NEXTHOP_FLAG_ONLINK)) { + ifp = if_lookup_by_index(nexthop->ifindex, nexthop->vrf_id); + if (!ifp) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug("nexthop %pNHv marked onlink but nhif %u doesn't exist", + nexthop, nexthop->ifindex); + return 0; + } + if (!if_is_operative(ifp)) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug("nexthop %pNHv marked onlink but nhif %s is not operational", + nexthop, ifp->name); + return 0; + } + return 1; + } + + if (top && + ((top->family == AF_INET && top->prefixlen == IPV4_MAX_BITLEN && + nexthop->gate.ipv4.s_addr == top->u.prefix4.s_addr) || + (top->family == AF_INET6 && top->prefixlen == IPV6_MAX_BITLEN && + memcmp(&nexthop->gate.ipv6, &top->u.prefix6, IPV6_MAX_BYTELEN) == + 0)) && + nexthop->vrf_id == vrf_id) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug( + " :%s: Attempting to install a max prefixlength route through itself", + __func__); + return 0; + } + + /* Validation for ipv4 mapped ipv6 nexthop. */ + if (IS_MAPPED_IPV6(&nexthop->gate.ipv6)) { + afi = AFI_IP; + ipv4 = &local_ipv4; + ipv4_mapped_ipv6_to_ipv4(&nexthop->gate.ipv6, ipv4); + } else { + ipv4 = &nexthop->gate.ipv4; + } + + /* Processing for nexthops with SR 'color' attribute, using + * the corresponding SR policy object. + */ + if (nexthop->srte_color) { + struct ipaddr endpoint = {0}; + struct zebra_sr_policy *policy; + + switch (afi) { + case AFI_IP: + endpoint.ipa_type = IPADDR_V4; + endpoint.ipaddr_v4 = *ipv4; + break; + case AFI_IP6: + endpoint.ipa_type = IPADDR_V6; + endpoint.ipaddr_v6 = nexthop->gate.ipv6; + break; + default: + flog_err(EC_LIB_DEVELOPMENT, + "%s: unknown address-family: %u", __func__, + afi); + exit(1); + } + + policy = zebra_sr_policy_find(nexthop->srte_color, &endpoint); + if (policy && policy->status == ZEBRA_SR_POLICY_UP) { + resolved = 0; + frr_each_safe (nhlfe_list, &policy->lsp->nhlfe_list, + nhlfe) { + if (!CHECK_FLAG(nhlfe->flags, + NHLFE_FLAG_SELECTED) + || CHECK_FLAG(nhlfe->flags, + NHLFE_FLAG_DELETED)) + continue; + SET_FLAG(nexthop->flags, + NEXTHOP_FLAG_RECURSIVE); + nexthop_set_resolved(afi, nhlfe->nexthop, + nexthop, policy); + resolved = 1; + } + if (resolved) + return 1; + } + } + + /* Make lookup prefix. */ + memset(&p, 0, sizeof(struct prefix)); + switch (afi) { + case AFI_IP: + p.family = AF_INET; + p.prefixlen = IPV4_MAX_BITLEN; + p.u.prefix4 = *ipv4; + break; + case AFI_IP6: + p.family = AF_INET6; + p.prefixlen = IPV6_MAX_BITLEN; + p.u.prefix6 = nexthop->gate.ipv6; + break; + default: + assert(afi != AFI_IP && afi != AFI_IP6); + break; + } + /* Lookup table. */ + table = zebra_vrf_table(afi, SAFI_UNICAST, nexthop->vrf_id); + /* get zvrf */ + zvrf = zebra_vrf_lookup_by_id(nexthop->vrf_id); + if (!table || !zvrf) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug(" %s: Table not found", __func__); + return 0; + } + + rn = route_node_match(table, (struct prefix *)&p); + while (rn) { + route_unlock_node(rn); + + /* Lookup should halt if we've matched against ourselves ('top', + * if specified) - i.e., we cannot have a nexthop NH1 is + * resolved by a route NH1. The exception is if the route is a + * host route. + */ + if (prefix_same(&rn->p, top)) + if (((afi == AFI_IP) + && (rn->p.prefixlen != IPV4_MAX_BITLEN)) + || ((afi == AFI_IP6) + && (rn->p.prefixlen != IPV6_MAX_BITLEN))) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug( + " %s: Matched against ourself and prefix length is not max bit length", + __func__); + return 0; + } + + /* Pick up selected route. */ + /* However, do not resolve over default route unless explicitly + * allowed. + */ + if (is_default_prefix(&rn->p) + && !rnh_resolve_via_default(zvrf, p.family)) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug( + " :%s: Resolved against default route", + __func__); + return 0; + } + + dest = rib_dest_from_rnode(rn); + if (dest && dest->selected_fib + && !CHECK_FLAG(dest->selected_fib->status, + ROUTE_ENTRY_REMOVED) + && dest->selected_fib->type != ZEBRA_ROUTE_TABLE) + match = dest->selected_fib; + + /* If there is no selected route or matched route is EGP, go up + * tree. + */ + if (!match) { + do { + rn = rn->parent; + } while (rn && rn->info == NULL); + if (rn) + route_lock_node(rn); + + continue; + } + + if ((match->type == ZEBRA_ROUTE_CONNECT) || + (RIB_SYSTEM_ROUTE(match) && RSYSTEM_ROUTE(type))) { + match = zebra_nhg_connected_ifindex(rn, match, + nexthop->ifindex); + + newhop = match->nhe->nhg.nexthop; + if (nexthop->type == NEXTHOP_TYPE_IPV4 || + nexthop->type == NEXTHOP_TYPE_IPV6) + nexthop->ifindex = newhop->ifindex; + else if (nexthop->ifindex != newhop->ifindex) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug( + "%s: %pNHv given ifindex does not match nexthops ifindex found: %pNHv", + __func__, nexthop, newhop); + /* + * NEXTHOP_TYPE_*_IFINDEX but ifindex + * doesn't match what we found. + */ + return 0; + } + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug( + "%s: CONNECT match %p (%pNG), newhop %pNHv", + __func__, match, match->nhe, newhop); + + return 1; + } else if (CHECK_FLAG(flags, ZEBRA_FLAG_ALLOW_RECURSION)) { + struct nexthop_group *nhg; + struct nexthop *resolver; + struct backup_nh_map_s map = {}; + + resolved = 0; + + /* Only useful if installed */ + if (!CHECK_FLAG(match->status, ROUTE_ENTRY_INSTALLED)) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug( + "%s: match %p (%pNG) not installed", + __func__, match, match->nhe); + + goto done_with_match; + } + + /* Examine installed nexthops; note that there + * may not be any installed primary nexthops if + * only backups are installed. + */ + nhg = rib_get_fib_nhg(match); + for (ALL_NEXTHOPS_PTR(nhg, newhop)) { + if (!nexthop_valid_resolve(nexthop, newhop)) + continue; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug( + "%s: RECURSIVE match %p (%pNG), newhop %pNHv", + __func__, match, match->nhe, + newhop); + + SET_FLAG(nexthop->flags, + NEXTHOP_FLAG_RECURSIVE); + resolver = nexthop_set_resolved(afi, newhop, + nexthop, NULL); + resolved = 1; + + /* If there are backup nexthops, capture + * that info with the resolving nexthop. + */ + if (resolver && newhop->backup_num > 0) { + resolve_backup_nexthops(newhop, + match->nhe, + resolver, nhe, + &map); + } + } + + /* Examine installed backup nexthops, if any. There + * are only installed backups *if* there is a + * dedicated fib list. The UI can also control use + * of backups for resolution. + */ + nhg = rib_get_fib_backup_nhg(match); + if (!use_recursive_backups || + nhg == NULL || nhg->nexthop == NULL) + goto done_with_match; + + for (ALL_NEXTHOPS_PTR(nhg, newhop)) { + if (!nexthop_valid_resolve(nexthop, newhop)) + continue; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug( + "%s: RECURSIVE match backup %p (%pNG), newhop %pNHv", + __func__, match, match->nhe, + newhop); + + SET_FLAG(nexthop->flags, + NEXTHOP_FLAG_RECURSIVE); + nexthop_set_resolved(afi, newhop, nexthop, + NULL); + resolved = 1; + } + +done_with_match: + /* Capture resolving mtu */ + if (resolved) { + if (pmtu) + *pmtu = match->mtu; + + } else if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug( + " %s: Recursion failed to find", + __func__); + + return resolved; + } else { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) { + zlog_debug( + " %s: Route Type %s has not turned on recursion", + __func__, zebra_route_string(type)); + if (type == ZEBRA_ROUTE_BGP + && !CHECK_FLAG(flags, ZEBRA_FLAG_IBGP)) + zlog_debug( + " EBGP: see \"disable-ebgp-connected-route-check\" or \"disable-connected-check\""); + } + return 0; + } + } + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug(" %s: Nexthop did not lookup in table", + __func__); + return 0; +} + +/* This function verifies reachability of one given nexthop, which can be + * numbered or unnumbered, IPv4 or IPv6. The result is unconditionally stored + * in nexthop->flags field. The nexthop->ifindex will be updated + * appropriately as well. + * + * An existing route map can turn an otherwise active nexthop into inactive, + * but not vice versa. + * + * The return value is the final value of 'ACTIVE' flag. + */ +static unsigned nexthop_active_check(struct route_node *rn, + struct route_entry *re, + struct nexthop *nexthop, + struct nhg_hash_entry *nhe) +{ + route_map_result_t ret = RMAP_PERMITMATCH; + afi_t family; + const struct prefix *p, *src_p; + struct zebra_vrf *zvrf; + uint32_t mtu = 0; + vrf_id_t vrf_id; + + srcdest_rnode_prefixes(rn, &p, &src_p); + + if (rn->p.family == AF_INET) + family = AFI_IP; + else if (rn->p.family == AF_INET6) + family = AFI_IP6; + else + family = AF_UNSPEC; + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: re %p, nexthop %pNHv", __func__, re, nexthop); + + /* + * If this is a kernel route, then if the interface is *up* then + * by golly gee whiz it's a good route. + */ + if (re->type == ZEBRA_ROUTE_KERNEL || re->type == ZEBRA_ROUTE_SYSTEM) { + struct interface *ifp; + + ifp = if_lookup_by_index(nexthop->ifindex, nexthop->vrf_id); + + if (ifp && (if_is_operative(ifp) || if_is_up(ifp))) { + SET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + goto skip_check; + } + } + + vrf_id = zvrf_id(rib_dest_vrf(rib_dest_from_rnode(rn))); + switch (nexthop->type) { + case NEXTHOP_TYPE_IFINDEX: + if (nexthop_active(nexthop, nhe, &rn->p, re->type, re->flags, + &mtu, vrf_id)) + SET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + else + UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + break; + case NEXTHOP_TYPE_IPV4: + case NEXTHOP_TYPE_IPV4_IFINDEX: + family = AFI_IP; + if (nexthop_active(nexthop, nhe, &rn->p, re->type, re->flags, + &mtu, vrf_id)) + SET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + else + UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + break; + case NEXTHOP_TYPE_IPV6: + family = AFI_IP6; + if (nexthop_active(nexthop, nhe, &rn->p, re->type, re->flags, + &mtu, vrf_id)) + SET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + else + UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + break; + case NEXTHOP_TYPE_IPV6_IFINDEX: + /* RFC 5549, v4 prefix with v6 NH */ + if (rn->p.family != AF_INET) + family = AFI_IP6; + + if (nexthop_active(nexthop, nhe, &rn->p, re->type, re->flags, + &mtu, vrf_id)) + SET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + else + UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + break; + case NEXTHOP_TYPE_BLACKHOLE: + SET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + break; + default: + break; + } + +skip_check: + + if (!CHECK_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE)) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug(" %s: Unable to find active nexthop", + __func__); + return 0; + } + + /* Capture recursive nexthop mtu. + * TODO -- the code used to just reset the re's value to zero + * for each nexthop, and then jam any resolving route's mtu value in, + * whether or not that was zero, or lt/gt any existing value? The + * way this is used appears to be as a floor value, so let's try + * using it that way here. + */ + if (mtu > 0) { + if (re->nexthop_mtu == 0 || re->nexthop_mtu > mtu) + re->nexthop_mtu = mtu; + } + + /* XXX: What exactly do those checks do? Do we support + * e.g. IPv4 routes with IPv6 nexthops or vice versa? + */ + if (RIB_SYSTEM_ROUTE(re) || (family == AFI_IP && p->family != AF_INET) + || (family == AFI_IP6 && p->family != AF_INET6)) + return CHECK_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + + /* The original code didn't determine the family correctly + * e.g. for NEXTHOP_TYPE_IFINDEX. Retrieve the correct afi + * from the rib_table_info in those cases. + * Possibly it may be better to use only the rib_table_info + * in every case. + */ + if (family == 0) { + struct rib_table_info *info; + + info = srcdest_rnode_table_info(rn); + family = info->afi; + } + + memset(&nexthop->rmap_src.ipv6, 0, sizeof(union g_addr)); + + zvrf = zebra_vrf_lookup_by_id(re->vrf_id); + if (!zvrf) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED) + zlog_debug(" %s: zvrf is NULL", __func__); + return CHECK_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + } + + /* It'll get set if required inside */ + ret = zebra_route_map_check(family, re->type, re->instance, p, nexthop, + zvrf, re->tag); + if (ret == RMAP_DENYMATCH) { + if (IS_ZEBRA_DEBUG_RIB) { + zlog_debug( + "%u:%pRN: Filtering out with NH %pNHv due to route map", + re->vrf_id, rn, nexthop); + } + UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + } + return CHECK_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); +} + +/* Helper function called after resolution to walk nhg rb trees + * and toggle the NEXTHOP_GROUP_VALID flag if the nexthop + * is active on singleton NHEs. + */ +static bool zebra_nhg_set_valid_if_active(struct nhg_hash_entry *nhe) +{ + struct nhg_connected *rb_node_dep = NULL; + bool valid = false; + + if (!zebra_nhg_depends_is_empty(nhe)) { + /* Is at least one depend valid? */ + frr_each(nhg_connected_tree, &nhe->nhg_depends, rb_node_dep) { + if (zebra_nhg_set_valid_if_active(rb_node_dep->nhe)) + valid = true; + } + + goto done; + } + + /* should be fully resolved singleton at this point */ + if (CHECK_FLAG(nhe->nhg.nexthop->flags, NEXTHOP_FLAG_ACTIVE)) + valid = true; + +done: + if (valid) + SET_FLAG(nhe->flags, NEXTHOP_GROUP_VALID); + + return valid; +} + +/* + * Process a list of nexthops, given an nhe, determining + * whether each one is ACTIVE/installable at this time. + */ +static uint32_t nexthop_list_active_update(struct route_node *rn, + struct route_entry *re, + struct nhg_hash_entry *nhe, + bool is_backup) +{ + union g_addr prev_src; + unsigned int prev_active, new_active; + ifindex_t prev_index; + uint32_t counter = 0; + struct nexthop *nexthop; + struct nexthop_group *nhg = &nhe->nhg; + + nexthop = nhg->nexthop; + + /* Init recursive nh mtu */ + re->nexthop_mtu = 0; + + /* Process nexthops one-by-one */ + for ( ; nexthop; nexthop = nexthop->next) { + + /* No protocol daemon provides src and so we're skipping + * tracking it + */ + prev_src = nexthop->rmap_src; + prev_active = CHECK_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE); + prev_index = nexthop->ifindex; + + /* Include the containing nhe for primary nexthops: if there's + * recursive resolution, we capture the backup info also. + */ + new_active = + nexthop_active_check(rn, re, nexthop, + (is_backup ? NULL : nhe)); + + /* + * We need to respect the multipath_num here + * as that what we should be able to install from + * a multipath perspective should not be a data plane + * decision point. + */ + if (new_active && counter >= zrouter.multipath_num) { + struct nexthop *nh; + + /* Set it and its resolved nexthop as inactive. */ + for (nh = nexthop; nh; nh = nh->resolved) + UNSET_FLAG(nh->flags, NEXTHOP_FLAG_ACTIVE); + + new_active = 0; + } + + if (new_active) + counter++; + + /* Check for changes to the nexthop - set ROUTE_ENTRY_CHANGED */ + if (prev_active != new_active || prev_index != nexthop->ifindex + || ((nexthop->type >= NEXTHOP_TYPE_IFINDEX + && nexthop->type < NEXTHOP_TYPE_IPV6) + && prev_src.ipv4.s_addr + != nexthop->rmap_src.ipv4.s_addr) + || ((nexthop->type >= NEXTHOP_TYPE_IPV6 + && nexthop->type < NEXTHOP_TYPE_BLACKHOLE) + && !(IPV6_ADDR_SAME(&prev_src.ipv6, + &nexthop->rmap_src.ipv6))) + || CHECK_FLAG(re->status, ROUTE_ENTRY_LABELS_CHANGED)) + SET_FLAG(re->status, ROUTE_ENTRY_CHANGED); + } + + return counter; +} + + +static uint32_t proto_nhg_nexthop_active_update(struct nexthop_group *nhg) +{ + struct nexthop *nh; + uint32_t curr_active = 0; + + /* Assume all active for now */ + + for (nh = nhg->nexthop; nh; nh = nh->next) { + SET_FLAG(nh->flags, NEXTHOP_FLAG_ACTIVE); + curr_active++; + } + + return curr_active; +} + +/* + * Iterate over all nexthops of the given RIB entry and refresh their + * ACTIVE flag. If any nexthop is found to toggle the ACTIVE flag, + * the whole re structure is flagged with ROUTE_ENTRY_CHANGED. + * + * Return value is the new number of active nexthops. + */ +int nexthop_active_update(struct route_node *rn, struct route_entry *re) +{ + struct nhg_hash_entry *curr_nhe; + uint32_t curr_active = 0, backup_active = 0; + + if (PROTO_OWNED(re->nhe)) + return proto_nhg_nexthop_active_update(&re->nhe->nhg); + + afi_t rt_afi = family2afi(rn->p.family); + + UNSET_FLAG(re->status, ROUTE_ENTRY_CHANGED); + + /* Make a local copy of the existing nhe, so we don't work on/modify + * the shared nhe. + */ + curr_nhe = zebra_nhe_copy(re->nhe, re->nhe->id); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: re %p nhe %p (%pNG), curr_nhe %p", __func__, re, + re->nhe, re->nhe, curr_nhe); + + /* Clear the existing id, if any: this will avoid any confusion + * if the id exists, and will also force the creation + * of a new nhe reflecting the changes we may make in this local copy. + */ + curr_nhe->id = 0; + + /* Process nexthops */ + curr_active = nexthop_list_active_update(rn, re, curr_nhe, false); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: re %p curr_active %u", __func__, re, + curr_active); + + /* If there are no backup nexthops, we are done */ + if (zebra_nhg_get_backup_nhg(curr_nhe) == NULL) + goto backups_done; + + backup_active = nexthop_list_active_update( + rn, re, curr_nhe->backup_info->nhe, true /*is_backup*/); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: re %p backup_active %u", __func__, re, + backup_active); + +backups_done: + + /* + * Ref or create an nhe that matches the current state of the + * nexthop(s). + */ + if (CHECK_FLAG(re->status, ROUTE_ENTRY_CHANGED)) { + struct nhg_hash_entry *new_nhe = NULL; + + new_nhe = zebra_nhg_rib_find_nhe(curr_nhe, rt_afi); + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug( + "%s: re %p CHANGED: nhe %p (%pNG) => new_nhe %p (%pNG)", + __func__, re, re->nhe, re->nhe, new_nhe, + new_nhe); + + route_entry_update_nhe(re, new_nhe); + } + + + /* Walk the NHE depends tree and toggle NEXTHOP_GROUP_VALID + * flag where appropriate. + */ + if (curr_active) + zebra_nhg_set_valid_if_active(re->nhe); + + /* + * Do not need the old / copied nhe anymore since it + * was either copied over into a new nhe or not + * used at all. + */ + zebra_nhg_free(curr_nhe); + return curr_active; +} + +/* Recursively construct a grp array of fully resolved IDs. + * + * This function allows us to account for groups within groups, + * by converting them into a flat array of IDs. + * + * nh_grp is modified at every level of recursion to append + * to it the next unique, fully resolved ID from the entire tree. + * + * + * Note: + * I'm pretty sure we only allow ONE level of group within group currently. + * But making this recursive just in case that ever changes. + */ +static uint8_t zebra_nhg_nhe2grp_internal(struct nh_grp *grp, + uint8_t curr_index, + struct nhg_hash_entry *nhe, + int max_num) +{ + struct nhg_connected *rb_node_dep = NULL; + struct nhg_hash_entry *depend = NULL; + uint8_t i = curr_index; + + frr_each(nhg_connected_tree, &nhe->nhg_depends, rb_node_dep) { + bool duplicate = false; + + if (i >= max_num) + goto done; + + depend = rb_node_dep->nhe; + + /* + * If its recursive, use its resolved nhe in the group + */ + if (CHECK_FLAG(depend->flags, NEXTHOP_GROUP_RECURSIVE)) { + depend = zebra_nhg_resolve(depend); + if (!depend) { + flog_err( + EC_ZEBRA_NHG_FIB_UPDATE, + "Failed to recursively resolve Nexthop Hash Entry in the group id=%pNG", + nhe); + continue; + } + } + + if (!zebra_nhg_depends_is_empty(depend)) { + /* This is a group within a group */ + i = zebra_nhg_nhe2grp_internal(grp, i, depend, max_num); + } else { + if (!CHECK_FLAG(depend->flags, NEXTHOP_GROUP_VALID)) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED + || IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: Nexthop ID (%u) not valid, not appending to dataplane install group", + __func__, depend->id); + continue; + } + + /* If the nexthop not installed/queued for install don't + * put in the ID array. + */ + if (!(CHECK_FLAG(depend->flags, NEXTHOP_GROUP_INSTALLED) + || CHECK_FLAG(depend->flags, + NEXTHOP_GROUP_QUEUED))) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED + || IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: Nexthop ID (%u) not installed or queued for install, not appending to dataplane install group", + __func__, depend->id); + continue; + } + + /* Check for duplicate IDs, ignore if found. */ + for (int j = 0; j < i; j++) { + if (depend->id == grp[j].id) { + duplicate = true; + break; + } + } + + if (duplicate) { + if (IS_ZEBRA_DEBUG_RIB_DETAILED + || IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: Nexthop ID (%u) is duplicate, not appending to dataplane install group", + __func__, depend->id); + continue; + } + + grp[i].id = depend->id; + grp[i].weight = depend->nhg.nexthop->weight; + i++; + } + } + + if (nhe->backup_info == NULL || nhe->backup_info->nhe == NULL) + goto done; + + /* TODO -- For now, we are not trying to use or install any + * backup info in this nexthop-id path: we aren't prepared + * to use the backups here yet. We're just debugging what we find. + */ + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: skipping backup nhe", __func__); + +done: + return i; +} + +/* Convert a nhe into a group array */ +uint8_t zebra_nhg_nhe2grp(struct nh_grp *grp, struct nhg_hash_entry *nhe, + int max_num) +{ + /* Call into the recursive function */ + return zebra_nhg_nhe2grp_internal(grp, 0, nhe, max_num); +} + +void zebra_nhg_install_kernel(struct nhg_hash_entry *nhe) +{ + struct nhg_connected *rb_node_dep = NULL; + + /* Resolve it first */ + nhe = zebra_nhg_resolve(nhe); + + /* Make sure all depends are installed/queued */ + frr_each(nhg_connected_tree, &nhe->nhg_depends, rb_node_dep) { + zebra_nhg_install_kernel(rb_node_dep->nhe); + } + + if (CHECK_FLAG(nhe->flags, NEXTHOP_GROUP_VALID) + && !CHECK_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED) + && !CHECK_FLAG(nhe->flags, NEXTHOP_GROUP_QUEUED)) { + /* Change its type to us since we are installing it */ + if (!ZEBRA_NHG_CREATED(nhe)) + nhe->type = ZEBRA_ROUTE_NHG; + + int ret = dplane_nexthop_add(nhe); + + switch (ret) { + case ZEBRA_DPLANE_REQUEST_QUEUED: + SET_FLAG(nhe->flags, NEXTHOP_GROUP_QUEUED); + break; + case ZEBRA_DPLANE_REQUEST_FAILURE: + flog_err( + EC_ZEBRA_DP_INSTALL_FAIL, + "Failed to install Nexthop ID (%pNG) into the kernel", + nhe); + break; + case ZEBRA_DPLANE_REQUEST_SUCCESS: + SET_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED); + zebra_nhg_handle_install(nhe); + break; + } + } +} + +void zebra_nhg_uninstall_kernel(struct nhg_hash_entry *nhe) +{ + if (CHECK_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED)) { + int ret = dplane_nexthop_delete(nhe); + + switch (ret) { + case ZEBRA_DPLANE_REQUEST_QUEUED: + SET_FLAG(nhe->flags, NEXTHOP_GROUP_QUEUED); + break; + case ZEBRA_DPLANE_REQUEST_FAILURE: + flog_err( + EC_ZEBRA_DP_DELETE_FAIL, + "Failed to uninstall Nexthop ID (%pNG) from the kernel", + nhe); + break; + case ZEBRA_DPLANE_REQUEST_SUCCESS: + UNSET_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED); + break; + } + } + + zebra_nhg_handle_uninstall(nhe); +} + +void zebra_nhg_dplane_result(struct zebra_dplane_ctx *ctx) +{ + enum dplane_op_e op; + enum zebra_dplane_result status; + uint32_t id = 0; + struct nhg_hash_entry *nhe = NULL; + + op = dplane_ctx_get_op(ctx); + status = dplane_ctx_get_status(ctx); + + id = dplane_ctx_get_nhe_id(ctx); + + if (IS_ZEBRA_DEBUG_DPLANE_DETAIL || IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug( + "Nexthop dplane ctx %p, op %s, nexthop ID (%u), result %s", + ctx, dplane_op2str(op), id, dplane_res2str(status)); + + switch (op) { + case DPLANE_OP_NH_DELETE: + if (status != ZEBRA_DPLANE_REQUEST_SUCCESS) + flog_err( + EC_ZEBRA_DP_DELETE_FAIL, + "Failed to uninstall Nexthop ID (%u) from the kernel", + id); + + /* We already free'd the data, nothing to do */ + break; + case DPLANE_OP_NH_INSTALL: + case DPLANE_OP_NH_UPDATE: + nhe = zebra_nhg_lookup_id(id); + + if (!nhe) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s operation preformed on Nexthop ID (%u) in the kernel, that we no longer have in our table", + dplane_op2str(op), id); + + break; + } + + UNSET_FLAG(nhe->flags, NEXTHOP_GROUP_QUEUED); + if (status == ZEBRA_DPLANE_REQUEST_SUCCESS) { + SET_FLAG(nhe->flags, NEXTHOP_GROUP_VALID); + SET_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED); + zebra_nhg_handle_install(nhe); + + /* If daemon nhg, send it an update */ + if (PROTO_OWNED(nhe)) + zsend_nhg_notify(nhe->type, nhe->zapi_instance, + nhe->zapi_session, nhe->id, + ZAPI_NHG_INSTALLED); + } else { + /* If daemon nhg, send it an update */ + if (PROTO_OWNED(nhe)) + zsend_nhg_notify(nhe->type, nhe->zapi_instance, + nhe->zapi_session, nhe->id, + ZAPI_NHG_FAIL_INSTALL); + + if (!(zebra_nhg_proto_nexthops_only() && + !PROTO_OWNED(nhe))) + flog_err( + EC_ZEBRA_DP_INSTALL_FAIL, + "Failed to install Nexthop (%pNG) into the kernel", + nhe); + } + break; + + case DPLANE_OP_ROUTE_INSTALL: + case DPLANE_OP_ROUTE_UPDATE: + case DPLANE_OP_ROUTE_DELETE: + case DPLANE_OP_ROUTE_NOTIFY: + case DPLANE_OP_LSP_INSTALL: + case DPLANE_OP_LSP_UPDATE: + case DPLANE_OP_LSP_DELETE: + case DPLANE_OP_LSP_NOTIFY: + case DPLANE_OP_PW_INSTALL: + case DPLANE_OP_PW_UNINSTALL: + case DPLANE_OP_SYS_ROUTE_ADD: + case DPLANE_OP_SYS_ROUTE_DELETE: + case DPLANE_OP_ADDR_INSTALL: + case DPLANE_OP_ADDR_UNINSTALL: + case DPLANE_OP_MAC_INSTALL: + case DPLANE_OP_MAC_DELETE: + case DPLANE_OP_NEIGH_INSTALL: + case DPLANE_OP_NEIGH_UPDATE: + case DPLANE_OP_NEIGH_DELETE: + case DPLANE_OP_NEIGH_IP_INSTALL: + case DPLANE_OP_NEIGH_IP_DELETE: + case DPLANE_OP_VTEP_ADD: + case DPLANE_OP_VTEP_DELETE: + case DPLANE_OP_RULE_ADD: + case DPLANE_OP_RULE_DELETE: + case DPLANE_OP_RULE_UPDATE: + case DPLANE_OP_NEIGH_DISCOVER: + case DPLANE_OP_BR_PORT_UPDATE: + case DPLANE_OP_NONE: + case DPLANE_OP_IPTABLE_ADD: + case DPLANE_OP_IPTABLE_DELETE: + case DPLANE_OP_IPSET_ADD: + case DPLANE_OP_IPSET_DELETE: + case DPLANE_OP_IPSET_ENTRY_ADD: + case DPLANE_OP_IPSET_ENTRY_DELETE: + case DPLANE_OP_NEIGH_TABLE_UPDATE: + case DPLANE_OP_GRE_SET: + case DPLANE_OP_INTF_ADDR_ADD: + case DPLANE_OP_INTF_ADDR_DEL: + case DPLANE_OP_INTF_NETCONFIG: + case DPLANE_OP_INTF_INSTALL: + case DPLANE_OP_INTF_UPDATE: + case DPLANE_OP_INTF_DELETE: + case DPLANE_OP_TC_INSTALL: + case DPLANE_OP_TC_UPDATE: + case DPLANE_OP_TC_DELETE: + break; + } +} + +static int zebra_nhg_sweep_entry(struct hash_bucket *bucket, void *arg) +{ + struct nhg_hash_entry *nhe = NULL; + + nhe = (struct nhg_hash_entry *)bucket->data; + + /* + * same logic as with routes. + * + * If older than startup time, we know we read them in from the + * kernel and have not gotten and update for them since startup + * from an upper level proto. + */ + if (zrouter.startup_time < nhe->uptime) + return HASHWALK_CONTINUE; + + /* + * If it's proto-owned and not being used by a route, remove it since + * we haven't gotten an update about it from the proto since startup. + * This means that either the config for it was removed or the daemon + * didn't get started. This handles graceful restart & retain scenario. + */ + if (PROTO_OWNED(nhe) && nhe->refcnt == 1) { + zebra_nhg_decrement_ref(nhe); + return HASHWALK_ABORT; + } + + /* + * If its being ref'd by routes, just let it be uninstalled via a route + * removal. + */ + if (ZEBRA_NHG_CREATED(nhe) && nhe->refcnt <= 0) { + zebra_nhg_uninstall_kernel(nhe); + return HASHWALK_ABORT; + } + + return HASHWALK_CONTINUE; +} + +void zebra_nhg_sweep_table(struct hash *hash) +{ + uint32_t count; + + /* + * Yes this is extremely odd. Effectively nhg's have + * other nexthop groups that depend on them and when you + * remove them, you can have other entries blown up. + * our hash code does not work with deleting multiple + * entries at a time and will possibly cause crashes + * So what to do? Whenever zebra_nhg_sweep_entry + * deletes an entry it will return HASHWALK_ABORT, + * cause that deletion might have triggered more. + * then we can just keep sweeping this table + * until nothing more is found to do. + */ + do { + count = hashcount(hash); + hash_walk(hash, zebra_nhg_sweep_entry, NULL); + } while (count != hashcount(hash)); +} + +static void zebra_nhg_mark_keep_entry(struct hash_bucket *bucket, void *arg) +{ + struct nhg_hash_entry *nhe = bucket->data; + + UNSET_FLAG(nhe->flags, NEXTHOP_GROUP_INSTALLED); +} + +/* + * When we are shutting down and we have retain mode enabled + * in zebra the process is to mark each vrf that it's + * routes should not be deleted. The problem with that + * is that shutdown actually free's up memory which + * causes the nexthop group's ref counts to go to zero + * we need a way to subtly tell the system to not remove + * the nexthop groups from the kernel at the same time. + * The easiest just looks like that we should not mark + * the nhg's as installed any more and when the ref count + * goes to zero we'll attempt to delete and do nothing + */ +void zebra_nhg_mark_keep(void) +{ + hash_iterate(zrouter.nhgs_id, zebra_nhg_mark_keep_entry, NULL); +} + +/* Global control to disable use of kernel nexthops, if available. We can't + * force the kernel to support nexthop ids, of course, but we can disable + * zebra's use of them, for testing e.g. By default, if the kernel supports + * nexthop ids, zebra uses them. + */ +void zebra_nhg_enable_kernel_nexthops(bool set) +{ + g_nexthops_enabled = set; +} + +bool zebra_nhg_kernel_nexthops_enabled(void) +{ + return g_nexthops_enabled; +} + +/* Global control for use of activated backups for recursive resolution. */ +void zebra_nhg_set_recursive_use_backups(bool set) +{ + use_recursive_backups = set; +} + +bool zebra_nhg_recursive_use_backups(void) +{ + return use_recursive_backups; +} + +/* + * Global control to only use kernel nexthops for protocol created NHGs. + * There are some use cases where you may not want zebra to implicitly + * create kernel nexthops for all routes and only create them for NHGs + * passed down by upper level protos. + * + * Default is off. + */ +void zebra_nhg_set_proto_nexthops_only(bool set) +{ + proto_nexthops_only = set; +} + +bool zebra_nhg_proto_nexthops_only(void) +{ + return proto_nexthops_only; +} + +/* Add NHE from upper level proto */ +struct nhg_hash_entry *zebra_nhg_proto_add(uint32_t id, int type, + uint16_t instance, uint32_t session, + struct nexthop_group *nhg, afi_t afi) +{ + struct nhg_hash_entry lookup; + struct nhg_hash_entry *new, *old; + struct nhg_connected *rb_node_dep = NULL; + struct nexthop *newhop; + bool replace = false; + + if (!nhg->nexthop) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug("%s: id %u, no nexthops passed to add", + __func__, id); + return NULL; + } + + + /* Set nexthop list as active, since they wont go through rib + * processing. + * + * Assuming valid/onlink for now. + * + * Once resolution is figured out, we won't need this! + */ + for (ALL_NEXTHOPS_PTR(nhg, newhop)) { + if (CHECK_FLAG(newhop->flags, NEXTHOP_FLAG_HAS_BACKUP)) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: id %u, backup nexthops not supported", + __func__, id); + return NULL; + } + + if (newhop->type == NEXTHOP_TYPE_BLACKHOLE) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: id %u, blackhole nexthop not supported", + __func__, id); + return NULL; + } + + if (newhop->type == NEXTHOP_TYPE_IFINDEX) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: id %u, nexthop without gateway not supported", + __func__, id); + return NULL; + } + + if (!newhop->ifindex) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: id %u, nexthop without ifindex is not supported", + __func__, id); + return NULL; + } + SET_FLAG(newhop->flags, NEXTHOP_FLAG_ACTIVE); + } + + zebra_nhe_init(&lookup, afi, nhg->nexthop); + lookup.nhg.nexthop = nhg->nexthop; + lookup.id = id; + lookup.type = type; + + old = zebra_nhg_lookup_id(id); + + if (old) { + /* + * This is a replace, just release NHE from ID for now, The + * depends/dependents may still be used in the replacement so + * we don't touch them other than to remove their refs to their + * old parent. + */ + replace = true; + hash_release(zrouter.nhgs_id, old); + + /* Free all the things */ + zebra_nhg_release_all_deps(old); + } + + new = zebra_nhg_rib_find_nhe(&lookup, afi); + + zebra_nhg_increment_ref(new); + + /* Capture zapi client info */ + new->zapi_instance = instance; + new->zapi_session = session; + + zebra_nhg_set_valid_if_active(new); + + zebra_nhg_install_kernel(new); + + if (old) { + /* + * Check to handle recving DEL while routes still in use then + * a replace. + * + * In this case we would have decremented the refcnt already + * but set the FLAG here. Go ahead and increment once to fix + * the misordering we have been sent. + */ + if (CHECK_FLAG(old->flags, NEXTHOP_GROUP_PROTO_RELEASED)) + zebra_nhg_increment_ref(old); + + rib_handle_nhg_replace(old, new); + + /* We have to decrement its singletons + * because some might not exist in NEW. + */ + if (!zebra_nhg_depends_is_empty(old)) { + frr_each (nhg_connected_tree, &old->nhg_depends, + rb_node_dep) + zebra_nhg_decrement_ref(rb_node_dep->nhe); + } + + /* Dont call the dec API, we dont want to uninstall the ID */ + old->refcnt = 0; + THREAD_OFF(old->timer); + zebra_nhg_free(old); + old = NULL; + } + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: %s nhe %p (%u), vrf %d, type %s", __func__, + (replace ? "replaced" : "added"), new, new->id, + new->vrf_id, zebra_route_string(new->type)); + + return new; +} + +/* Delete NHE from upper level proto, caller must decrement ref */ +struct nhg_hash_entry *zebra_nhg_proto_del(uint32_t id, int type) +{ + struct nhg_hash_entry *nhe; + + nhe = zebra_nhg_lookup_id(id); + + if (!nhe) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug("%s: id %u, lookup failed", __func__, id); + + return NULL; + } + + if (type != nhe->type) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: id %u, type %s mismatch, sent by %s, ignoring", + __func__, id, zebra_route_string(nhe->type), + zebra_route_string(type)); + return NULL; + } + + if (CHECK_FLAG(nhe->flags, NEXTHOP_GROUP_PROTO_RELEASED)) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug("%s: id %u, already released", __func__, id); + + return NULL; + } + + SET_FLAG(nhe->flags, NEXTHOP_GROUP_PROTO_RELEASED); + + if (nhe->refcnt > 1) { + if (IS_ZEBRA_DEBUG_NHG) + zlog_debug( + "%s: %pNG, still being used by routes refcnt %u", + __func__, nhe, nhe->refcnt); + return nhe; + } + + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug("%s: deleted nhe %p (%pNG), vrf %d, type %s", + __func__, nhe, nhe, nhe->vrf_id, + zebra_route_string(nhe->type)); + + return nhe; +} + +struct nhg_score_proto_iter { + int type; + struct list *found; +}; + +static void zebra_nhg_score_proto_entry(struct hash_bucket *bucket, void *arg) +{ + struct nhg_hash_entry *nhe; + struct nhg_score_proto_iter *iter; + + nhe = (struct nhg_hash_entry *)bucket->data; + iter = arg; + + /* Needs to match type and outside zebra ID space */ + if (nhe->type == iter->type && PROTO_OWNED(nhe)) { + if (IS_ZEBRA_DEBUG_NHG_DETAIL) + zlog_debug( + "%s: found nhe %p (%pNG), vrf %d, type %s after client disconnect", + __func__, nhe, nhe, nhe->vrf_id, + zebra_route_string(nhe->type)); + + /* Add to removal list */ + listnode_add(iter->found, nhe); + } +} + +/* Remove specific by proto NHGs */ +unsigned long zebra_nhg_score_proto(int type) +{ + struct nhg_hash_entry *nhe; + struct nhg_score_proto_iter iter = {}; + struct listnode *ln; + unsigned long count; + + iter.type = type; + iter.found = list_new(); + + /* Find matching entries to remove */ + hash_iterate(zrouter.nhgs_id, zebra_nhg_score_proto_entry, &iter); + + /* Now remove them */ + for (ALL_LIST_ELEMENTS_RO(iter.found, ln, nhe)) { + /* + * This should be the last ref if we remove client routes too, + * and thus should remove and free them. + */ + zebra_nhg_decrement_ref(nhe); + } + + count = iter.found->count; + list_delete(&iter.found); + + return count; +} + +printfrr_ext_autoreg_p("NG", printfrr_nhghe); +static ssize_t printfrr_nhghe(struct fbuf *buf, struct printfrr_eargs *ea, + const void *ptr) +{ + const struct nhg_hash_entry *nhe = ptr; + const struct nhg_connected *dep; + ssize_t ret = 0; + + if (!nhe) + return bputs(buf, "[NULL]"); + + ret += bprintfrr(buf, "%u[", nhe->id); + if (nhe->ifp) + ret += printfrr_nhs(buf, nhe->nhg.nexthop); + else { + int count = zebra_nhg_depends_count(nhe); + + frr_each (nhg_connected_tree_const, &nhe->nhg_depends, dep) { + ret += bprintfrr(buf, "%u", dep->nhe->id); + if (count > 1) + ret += bputs(buf, "/"); + count--; + } + } + + ret += bputs(buf, "]"); + return ret; +} |