// SPDX-License-Identifier: GPL-2.0 /* Generic nexthop implementation * * Copyright (c) 2017-19 Cumulus Networks * Copyright (c) 2017-19 David Ahern */ #include #include #include #include #include #include #include #include #include #include #include #define NH_RES_DEFAULT_IDLE_TIMER (120 * HZ) #define NH_RES_DEFAULT_UNBALANCED_TIMER 0 /* No forced rebalancing. */ static void remove_nexthop(struct net *net, struct nexthop *nh, struct nl_info *nlinfo); #define NH_DEV_HASHBITS 8 #define NH_DEV_HASHSIZE (1U << NH_DEV_HASHBITS) #define NHA_OP_FLAGS_DUMP_ALL (NHA_OP_FLAG_DUMP_STATS | \ NHA_OP_FLAG_DUMP_HW_STATS) static const struct nla_policy rtm_nh_policy_new[] = { [NHA_ID] = { .type = NLA_U32 }, [NHA_GROUP] = { .type = NLA_BINARY }, [NHA_GROUP_TYPE] = { .type = NLA_U16 }, [NHA_BLACKHOLE] = { .type = NLA_FLAG }, [NHA_OIF] = { .type = NLA_U32 }, [NHA_GATEWAY] = { .type = NLA_BINARY }, [NHA_ENCAP_TYPE] = { .type = NLA_U16 }, [NHA_ENCAP] = { .type = NLA_NESTED }, [NHA_FDB] = { .type = NLA_FLAG }, [NHA_RES_GROUP] = { .type = NLA_NESTED }, [NHA_HW_STATS_ENABLE] = NLA_POLICY_MAX(NLA_U32, true), }; static const struct nla_policy rtm_nh_policy_get[] = { [NHA_ID] = { .type = NLA_U32 }, [NHA_OP_FLAGS] = NLA_POLICY_MASK(NLA_U32, NHA_OP_FLAGS_DUMP_ALL), }; static const struct nla_policy rtm_nh_policy_del[] = { [NHA_ID] = { .type = NLA_U32 }, }; static const struct nla_policy rtm_nh_policy_dump[] = { [NHA_OIF] = { .type = NLA_U32 }, [NHA_GROUPS] = { .type = NLA_FLAG }, [NHA_MASTER] = { .type = NLA_U32 }, [NHA_FDB] = { .type = NLA_FLAG }, [NHA_OP_FLAGS] = NLA_POLICY_MASK(NLA_U32, NHA_OP_FLAGS_DUMP_ALL), }; static const struct nla_policy rtm_nh_res_policy_new[] = { [NHA_RES_GROUP_BUCKETS] = { .type = NLA_U16 }, [NHA_RES_GROUP_IDLE_TIMER] = { .type = NLA_U32 }, [NHA_RES_GROUP_UNBALANCED_TIMER] = { .type = NLA_U32 }, }; static const struct nla_policy rtm_nh_policy_dump_bucket[] = { [NHA_ID] = { .type = NLA_U32 }, [NHA_OIF] = { .type = NLA_U32 }, [NHA_MASTER] = { .type = NLA_U32 }, [NHA_RES_BUCKET] = { .type = NLA_NESTED }, }; static const struct nla_policy rtm_nh_res_bucket_policy_dump[] = { [NHA_RES_BUCKET_NH_ID] = { .type = NLA_U32 }, }; static const struct nla_policy rtm_nh_policy_get_bucket[] = { [NHA_ID] = { .type = NLA_U32 }, [NHA_RES_BUCKET] = { .type = NLA_NESTED }, }; static const struct nla_policy rtm_nh_res_bucket_policy_get[] = { [NHA_RES_BUCKET_INDEX] = { .type = NLA_U16 }, }; static bool nexthop_notifiers_is_empty(struct net *net) { return !net->nexthop.notifier_chain.head; } static void __nh_notifier_single_info_init(struct nh_notifier_single_info *nh_info, const struct nh_info *nhi) { nh_info->dev = nhi->fib_nhc.nhc_dev; nh_info->gw_family = nhi->fib_nhc.nhc_gw_family; if (nh_info->gw_family == AF_INET) nh_info->ipv4 = nhi->fib_nhc.nhc_gw.ipv4; else if (nh_info->gw_family == AF_INET6) nh_info->ipv6 = nhi->fib_nhc.nhc_gw.ipv6; nh_info->id = nhi->nh_parent->id; nh_info->is_reject = nhi->reject_nh; nh_info->is_fdb = nhi->fdb_nh; nh_info->has_encap = !!nhi->fib_nhc.nhc_lwtstate; } static int nh_notifier_single_info_init(struct nh_notifier_info *info, const struct nexthop *nh) { struct nh_info *nhi = rtnl_dereference(nh->nh_info); info->type = NH_NOTIFIER_INFO_TYPE_SINGLE; info->nh = kzalloc(sizeof(*info->nh), GFP_KERNEL); if (!info->nh) return -ENOMEM; __nh_notifier_single_info_init(info->nh, nhi); return 0; } static void nh_notifier_single_info_fini(struct nh_notifier_info *info) { kfree(info->nh); } static int nh_notifier_mpath_info_init(struct nh_notifier_info *info, struct nh_group *nhg) { u16 num_nh = nhg->num_nh; int i; info->type = NH_NOTIFIER_INFO_TYPE_GRP; info->nh_grp = kzalloc(struct_size(info->nh_grp, nh_entries, num_nh), GFP_KERNEL); if (!info->nh_grp) return -ENOMEM; info->nh_grp->num_nh = num_nh; info->nh_grp->is_fdb = nhg->fdb_nh; info->nh_grp->hw_stats = nhg->hw_stats; for (i = 0; i < num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; struct nh_info *nhi; nhi = rtnl_dereference(nhge->nh->nh_info); info->nh_grp->nh_entries[i].weight = nhge->weight; __nh_notifier_single_info_init(&info->nh_grp->nh_entries[i].nh, nhi); } return 0; } static int nh_notifier_res_table_info_init(struct nh_notifier_info *info, struct nh_group *nhg) { struct nh_res_table *res_table = rtnl_dereference(nhg->res_table); u16 num_nh_buckets = res_table->num_nh_buckets; unsigned long size; u16 i; info->type = NH_NOTIFIER_INFO_TYPE_RES_TABLE; size = struct_size(info->nh_res_table, nhs, num_nh_buckets); info->nh_res_table = __vmalloc(size, GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN); if (!info->nh_res_table) return -ENOMEM; info->nh_res_table->num_nh_buckets = num_nh_buckets; info->nh_res_table->hw_stats = nhg->hw_stats; for (i = 0; i < num_nh_buckets; i++) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; struct nh_grp_entry *nhge; struct nh_info *nhi; nhge = rtnl_dereference(bucket->nh_entry); nhi = rtnl_dereference(nhge->nh->nh_info); __nh_notifier_single_info_init(&info->nh_res_table->nhs[i], nhi); } return 0; } static int nh_notifier_grp_info_init(struct nh_notifier_info *info, const struct nexthop *nh) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); if (nhg->hash_threshold) return nh_notifier_mpath_info_init(info, nhg); else if (nhg->resilient) return nh_notifier_res_table_info_init(info, nhg); return -EINVAL; } static void nh_notifier_grp_info_fini(struct nh_notifier_info *info, const struct nexthop *nh) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); if (nhg->hash_threshold) kfree(info->nh_grp); else if (nhg->resilient) vfree(info->nh_res_table); } static int nh_notifier_info_init(struct nh_notifier_info *info, const struct nexthop *nh) { info->id = nh->id; if (nh->is_group) return nh_notifier_grp_info_init(info, nh); else return nh_notifier_single_info_init(info, nh); } static void nh_notifier_info_fini(struct nh_notifier_info *info, const struct nexthop *nh) { if (nh->is_group) nh_notifier_grp_info_fini(info, nh); else nh_notifier_single_info_fini(info); } static int call_nexthop_notifiers(struct net *net, enum nexthop_event_type event_type, struct nexthop *nh, struct netlink_ext_ack *extack) { struct nh_notifier_info info = { .net = net, .extack = extack, }; int err; ASSERT_RTNL(); if (nexthop_notifiers_is_empty(net)) return 0; err = nh_notifier_info_init(&info, nh); if (err) { NL_SET_ERR_MSG(extack, "Failed to initialize nexthop notifier info"); return err; } err = blocking_notifier_call_chain(&net->nexthop.notifier_chain, event_type, &info); nh_notifier_info_fini(&info, nh); return notifier_to_errno(err); } static int nh_notifier_res_bucket_idle_timer_get(const struct nh_notifier_info *info, bool force, unsigned int *p_idle_timer_ms) { struct nh_res_table *res_table; struct nh_group *nhg; struct nexthop *nh; int err = 0; /* When 'force' is false, nexthop bucket replacement is performed * because the bucket was deemed to be idle. In this case, capable * listeners can choose to perform an atomic replacement: The bucket is * only replaced if it is inactive. However, if the idle timer interval * is smaller than the interval in which a listener is querying * buckets' activity from the device, then atomic replacement should * not be tried. Pass the idle timer value to listeners, so that they * could determine which type of replacement to perform. */ if (force) { *p_idle_timer_ms = 0; return 0; } rcu_read_lock(); nh = nexthop_find_by_id(info->net, info->id); if (!nh) { err = -EINVAL; goto out; } nhg = rcu_dereference(nh->nh_grp); res_table = rcu_dereference(nhg->res_table); *p_idle_timer_ms = jiffies_to_msecs(res_table->idle_timer); out: rcu_read_unlock(); return err; } static int nh_notifier_res_bucket_info_init(struct nh_notifier_info *info, u16 bucket_index, bool force, struct nh_info *oldi, struct nh_info *newi) { unsigned int idle_timer_ms; int err; err = nh_notifier_res_bucket_idle_timer_get(info, force, &idle_timer_ms); if (err) return err; info->type = NH_NOTIFIER_INFO_TYPE_RES_BUCKET; info->nh_res_bucket = kzalloc(sizeof(*info->nh_res_bucket), GFP_KERNEL); if (!info->nh_res_bucket) return -ENOMEM; info->nh_res_bucket->bucket_index = bucket_index; info->nh_res_bucket->idle_timer_ms = idle_timer_ms; info->nh_res_bucket->force = force; __nh_notifier_single_info_init(&info->nh_res_bucket->old_nh, oldi); __nh_notifier_single_info_init(&info->nh_res_bucket->new_nh, newi); return 0; } static void nh_notifier_res_bucket_info_fini(struct nh_notifier_info *info) { kfree(info->nh_res_bucket); } static int __call_nexthop_res_bucket_notifiers(struct net *net, u32 nhg_id, u16 bucket_index, bool force, struct nh_info *oldi, struct nh_info *newi, struct netlink_ext_ack *extack) { struct nh_notifier_info info = { .net = net, .extack = extack, .id = nhg_id, }; int err; if (nexthop_notifiers_is_empty(net)) return 0; err = nh_notifier_res_bucket_info_init(&info, bucket_index, force, oldi, newi); if (err) return err; err = blocking_notifier_call_chain(&net->nexthop.notifier_chain, NEXTHOP_EVENT_BUCKET_REPLACE, &info); nh_notifier_res_bucket_info_fini(&info); return notifier_to_errno(err); } /* There are three users of RES_TABLE, and NHs etc. referenced from there: * * 1) a collection of callbacks for NH maintenance. This operates under * RTNL, * 2) the delayed work that gradually balances the resilient table, * 3) and nexthop_select_path(), operating under RCU. * * Both the delayed work and the RTNL block are writers, and need to * maintain mutual exclusion. Since there are only two and well-known * writers for each table, the RTNL code can make sure it has exclusive * access thus: * * - Have the DW operate without locking; * - synchronously cancel the DW; * - do the writing; * - if the write was not actually a delete, call upkeep, which schedules * DW again if necessary. * * The functions that are always called from the RTNL context use * rtnl_dereference(). The functions that can also be called from the DW do * a raw dereference and rely on the above mutual exclusion scheme. */ #define nh_res_dereference(p) (rcu_dereference_raw(p)) static int call_nexthop_res_bucket_notifiers(struct net *net, u32 nhg_id, u16 bucket_index, bool force, struct nexthop *old_nh, struct nexthop *new_nh, struct netlink_ext_ack *extack) { struct nh_info *oldi = nh_res_dereference(old_nh->nh_info); struct nh_info *newi = nh_res_dereference(new_nh->nh_info); return __call_nexthop_res_bucket_notifiers(net, nhg_id, bucket_index, force, oldi, newi, extack); } static int call_nexthop_res_table_notifiers(struct net *net, struct nexthop *nh, struct netlink_ext_ack *extack) { struct nh_notifier_info info = { .net = net, .extack = extack, .id = nh->id, }; struct nh_group *nhg; int err; ASSERT_RTNL(); if (nexthop_notifiers_is_empty(net)) return 0; /* At this point, the nexthop buckets are still not populated. Only * emit a notification with the logical nexthops, so that a listener * could potentially veto it in case of unsupported configuration. */ nhg = rtnl_dereference(nh->nh_grp); err = nh_notifier_mpath_info_init(&info, nhg); if (err) { NL_SET_ERR_MSG(extack, "Failed to initialize nexthop notifier info"); return err; } err = blocking_notifier_call_chain(&net->nexthop.notifier_chain, NEXTHOP_EVENT_RES_TABLE_PRE_REPLACE, &info); kfree(info.nh_grp); return notifier_to_errno(err); } static int call_nexthop_notifier(struct notifier_block *nb, struct net *net, enum nexthop_event_type event_type, struct nexthop *nh, struct netlink_ext_ack *extack) { struct nh_notifier_info info = { .net = net, .extack = extack, }; int err; err = nh_notifier_info_init(&info, nh); if (err) return err; err = nb->notifier_call(nb, event_type, &info); nh_notifier_info_fini(&info, nh); return notifier_to_errno(err); } static unsigned int nh_dev_hashfn(unsigned int val) { unsigned int mask = NH_DEV_HASHSIZE - 1; return (val ^ (val >> NH_DEV_HASHBITS) ^ (val >> (NH_DEV_HASHBITS * 2))) & mask; } static void nexthop_devhash_add(struct net *net, struct nh_info *nhi) { struct net_device *dev = nhi->fib_nhc.nhc_dev; struct hlist_head *head; unsigned int hash; WARN_ON(!dev); hash = nh_dev_hashfn(dev->ifindex); head = &net->nexthop.devhash[hash]; hlist_add_head(&nhi->dev_hash, head); } static void nexthop_free_group(struct nexthop *nh) { struct nh_group *nhg; int i; nhg = rcu_dereference_raw(nh->nh_grp); for (i = 0; i < nhg->num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; WARN_ON(!list_empty(&nhge->nh_list)); free_percpu(nhge->stats); nexthop_put(nhge->nh); } WARN_ON(nhg->spare == nhg); if (nhg->resilient) vfree(rcu_dereference_raw(nhg->res_table)); kfree(nhg->spare); kfree(nhg); } static void nexthop_free_single(struct nexthop *nh) { struct nh_info *nhi; nhi = rcu_dereference_raw(nh->nh_info); switch (nhi->family) { case AF_INET: fib_nh_release(nh->net, &nhi->fib_nh); break; case AF_INET6: ipv6_stub->fib6_nh_release(&nhi->fib6_nh); break; } kfree(nhi); } void nexthop_free_rcu(struct rcu_head *head) { struct nexthop *nh = container_of(head, struct nexthop, rcu); if (nh->is_group) nexthop_free_group(nh); else nexthop_free_single(nh); kfree(nh); } EXPORT_SYMBOL_GPL(nexthop_free_rcu); static struct nexthop *nexthop_alloc(void) { struct nexthop *nh; nh = kzalloc(sizeof(struct nexthop), GFP_KERNEL); if (nh) { INIT_LIST_HEAD(&nh->fi_list); INIT_LIST_HEAD(&nh->f6i_list); INIT_LIST_HEAD(&nh->grp_list); INIT_LIST_HEAD(&nh->fdb_list); } return nh; } static struct nh_group *nexthop_grp_alloc(u16 num_nh) { struct nh_group *nhg; nhg = kzalloc(struct_size(nhg, nh_entries, num_nh), GFP_KERNEL); if (nhg) nhg->num_nh = num_nh; return nhg; } static void nh_res_table_upkeep_dw(struct work_struct *work); static struct nh_res_table * nexthop_res_table_alloc(struct net *net, u32 nhg_id, struct nh_config *cfg) { const u16 num_nh_buckets = cfg->nh_grp_res_num_buckets; struct nh_res_table *res_table; unsigned long size; size = struct_size(res_table, nh_buckets, num_nh_buckets); res_table = __vmalloc(size, GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN); if (!res_table) return NULL; res_table->net = net; res_table->nhg_id = nhg_id; INIT_DELAYED_WORK(&res_table->upkeep_dw, &nh_res_table_upkeep_dw); INIT_LIST_HEAD(&res_table->uw_nh_entries); res_table->idle_timer = cfg->nh_grp_res_idle_timer; res_table->unbalanced_timer = cfg->nh_grp_res_unbalanced_timer; res_table->num_nh_buckets = num_nh_buckets; return res_table; } static void nh_base_seq_inc(struct net *net) { while (++net->nexthop.seq == 0) ; } /* no reference taken; rcu lock or rtnl must be held */ struct nexthop *nexthop_find_by_id(struct net *net, u32 id) { struct rb_node **pp, *parent = NULL, *next; pp = &net->nexthop.rb_root.rb_node; while (1) { struct nexthop *nh; next = rcu_dereference_raw(*pp); if (!next) break; parent = next; nh = rb_entry(parent, struct nexthop, rb_node); if (id < nh->id) pp = &next->rb_left; else if (id > nh->id) pp = &next->rb_right; else return nh; } return NULL; } EXPORT_SYMBOL_GPL(nexthop_find_by_id); /* used for auto id allocation; called with rtnl held */ static u32 nh_find_unused_id(struct net *net) { u32 id_start = net->nexthop.last_id_allocated; while (1) { net->nexthop.last_id_allocated++; if (net->nexthop.last_id_allocated == id_start) break; if (!nexthop_find_by_id(net, net->nexthop.last_id_allocated)) return net->nexthop.last_id_allocated; } return 0; } static void nh_res_time_set_deadline(unsigned long next_time, unsigned long *deadline) { if (time_before(next_time, *deadline)) *deadline = next_time; } static clock_t nh_res_table_unbalanced_time(struct nh_res_table *res_table) { if (list_empty(&res_table->uw_nh_entries)) return 0; return jiffies_delta_to_clock_t(jiffies - res_table->unbalanced_since); } static int nla_put_nh_group_res(struct sk_buff *skb, struct nh_group *nhg) { struct nh_res_table *res_table = rtnl_dereference(nhg->res_table); struct nlattr *nest; nest = nla_nest_start(skb, NHA_RES_GROUP); if (!nest) return -EMSGSIZE; if (nla_put_u16(skb, NHA_RES_GROUP_BUCKETS, res_table->num_nh_buckets) || nla_put_u32(skb, NHA_RES_GROUP_IDLE_TIMER, jiffies_to_clock_t(res_table->idle_timer)) || nla_put_u32(skb, NHA_RES_GROUP_UNBALANCED_TIMER, jiffies_to_clock_t(res_table->unbalanced_timer)) || nla_put_u64_64bit(skb, NHA_RES_GROUP_UNBALANCED_TIME, nh_res_table_unbalanced_time(res_table), NHA_RES_GROUP_PAD)) goto nla_put_failure; nla_nest_end(skb, nest); return 0; nla_put_failure: nla_nest_cancel(skb, nest); return -EMSGSIZE; } static void nh_grp_entry_stats_inc(struct nh_grp_entry *nhge) { struct nh_grp_entry_stats *cpu_stats; cpu_stats = get_cpu_ptr(nhge->stats); u64_stats_update_begin(&cpu_stats->syncp); u64_stats_inc(&cpu_stats->packets); u64_stats_update_end(&cpu_stats->syncp); put_cpu_ptr(cpu_stats); } static void nh_grp_entry_stats_read(struct nh_grp_entry *nhge, u64 *ret_packets) { int i; *ret_packets = 0; for_each_possible_cpu(i) { struct nh_grp_entry_stats *cpu_stats; unsigned int start; u64 packets; cpu_stats = per_cpu_ptr(nhge->stats, i); do { start = u64_stats_fetch_begin(&cpu_stats->syncp); packets = u64_stats_read(&cpu_stats->packets); } while (u64_stats_fetch_retry(&cpu_stats->syncp, start)); *ret_packets += packets; } } static int nh_notifier_grp_hw_stats_init(struct nh_notifier_info *info, const struct nexthop *nh) { struct nh_group *nhg; int i; ASSERT_RTNL(); nhg = rtnl_dereference(nh->nh_grp); info->id = nh->id; info->type = NH_NOTIFIER_INFO_TYPE_GRP_HW_STATS; info->nh_grp_hw_stats = kzalloc(struct_size(info->nh_grp_hw_stats, stats, nhg->num_nh), GFP_KERNEL); if (!info->nh_grp_hw_stats) return -ENOMEM; info->nh_grp_hw_stats->num_nh = nhg->num_nh; for (i = 0; i < nhg->num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; info->nh_grp_hw_stats->stats[i].id = nhge->nh->id; } return 0; } static void nh_notifier_grp_hw_stats_fini(struct nh_notifier_info *info) { kfree(info->nh_grp_hw_stats); } void nh_grp_hw_stats_report_delta(struct nh_notifier_grp_hw_stats_info *info, unsigned int nh_idx, u64 delta_packets) { info->hw_stats_used = true; info->stats[nh_idx].packets += delta_packets; } EXPORT_SYMBOL(nh_grp_hw_stats_report_delta); static void nh_grp_hw_stats_apply_update(struct nexthop *nh, struct nh_notifier_info *info) { struct nh_group *nhg; int i; ASSERT_RTNL(); nhg = rtnl_dereference(nh->nh_grp); for (i = 0; i < nhg->num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; nhge->packets_hw += info->nh_grp_hw_stats->stats[i].packets; } } static int nh_grp_hw_stats_update(struct nexthop *nh, bool *hw_stats_used) { struct nh_notifier_info info = { .net = nh->net, }; struct net *net = nh->net; int err; if (nexthop_notifiers_is_empty(net)) { *hw_stats_used = false; return 0; } err = nh_notifier_grp_hw_stats_init(&info, nh); if (err) return err; err = blocking_notifier_call_chain(&net->nexthop.notifier_chain, NEXTHOP_EVENT_HW_STATS_REPORT_DELTA, &info); /* Cache whatever we got, even if there was an error, otherwise the * successful stats retrievals would get lost. */ nh_grp_hw_stats_apply_update(nh, &info); *hw_stats_used = info.nh_grp_hw_stats->hw_stats_used; nh_notifier_grp_hw_stats_fini(&info); return notifier_to_errno(err); } static int nla_put_nh_group_stats_entry(struct sk_buff *skb, struct nh_grp_entry *nhge, u32 op_flags) { struct nlattr *nest; u64 packets; nh_grp_entry_stats_read(nhge, &packets); nest = nla_nest_start(skb, NHA_GROUP_STATS_ENTRY); if (!nest) return -EMSGSIZE; if (nla_put_u32(skb, NHA_GROUP_STATS_ENTRY_ID, nhge->nh->id) || nla_put_uint(skb, NHA_GROUP_STATS_ENTRY_PACKETS, packets + nhge->packets_hw)) goto nla_put_failure; if (op_flags & NHA_OP_FLAG_DUMP_HW_STATS && nla_put_uint(skb, NHA_GROUP_STATS_ENTRY_PACKETS_HW, nhge->packets_hw)) goto nla_put_failure; nla_nest_end(skb, nest); return 0; nla_put_failure: nla_nest_cancel(skb, nest); return -EMSGSIZE; } static int nla_put_nh_group_stats(struct sk_buff *skb, struct nexthop *nh, u32 op_flags) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); struct nlattr *nest; bool hw_stats_used; int err; int i; if (nla_put_u32(skb, NHA_HW_STATS_ENABLE, nhg->hw_stats)) goto err_out; if (op_flags & NHA_OP_FLAG_DUMP_HW_STATS && nhg->hw_stats) { err = nh_grp_hw_stats_update(nh, &hw_stats_used); if (err) goto out; if (nla_put_u32(skb, NHA_HW_STATS_USED, hw_stats_used)) goto err_out; } nest = nla_nest_start(skb, NHA_GROUP_STATS); if (!nest) goto err_out; for (i = 0; i < nhg->num_nh; i++) if (nla_put_nh_group_stats_entry(skb, &nhg->nh_entries[i], op_flags)) goto cancel_out; nla_nest_end(skb, nest); return 0; cancel_out: nla_nest_cancel(skb, nest); err_out: err = -EMSGSIZE; out: return err; } static int nla_put_nh_group(struct sk_buff *skb, struct nexthop *nh, u32 op_flags, u32 *resp_op_flags) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); struct nexthop_grp *p; size_t len = nhg->num_nh * sizeof(*p); struct nlattr *nla; u16 group_type = 0; u16 weight; int i; *resp_op_flags |= NHA_OP_FLAG_RESP_GRP_RESVD_0; if (nhg->hash_threshold) group_type = NEXTHOP_GRP_TYPE_MPATH; else if (nhg->resilient) group_type = NEXTHOP_GRP_TYPE_RES; if (nla_put_u16(skb, NHA_GROUP_TYPE, group_type)) goto nla_put_failure; nla = nla_reserve(skb, NHA_GROUP, len); if (!nla) goto nla_put_failure; p = nla_data(nla); for (i = 0; i < nhg->num_nh; ++i) { weight = nhg->nh_entries[i].weight - 1; *p++ = (struct nexthop_grp) { .id = nhg->nh_entries[i].nh->id, .weight = weight, .weight_high = weight >> 8, }; } if (nhg->resilient && nla_put_nh_group_res(skb, nhg)) goto nla_put_failure; if (op_flags & NHA_OP_FLAG_DUMP_STATS && (nla_put_u32(skb, NHA_HW_STATS_ENABLE, nhg->hw_stats) || nla_put_nh_group_stats(skb, nh, op_flags))) goto nla_put_failure; return 0; nla_put_failure: return -EMSGSIZE; } static int nh_fill_node(struct sk_buff *skb, struct nexthop *nh, int event, u32 portid, u32 seq, unsigned int nlflags, u32 op_flags) { struct fib6_nh *fib6_nh; struct fib_nh *fib_nh; struct nlmsghdr *nlh; struct nh_info *nhi; struct nhmsg *nhm; nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nhm), nlflags); if (!nlh) return -EMSGSIZE; nhm = nlmsg_data(nlh); nhm->nh_family = AF_UNSPEC; nhm->nh_flags = nh->nh_flags; nhm->nh_protocol = nh->protocol; nhm->nh_scope = 0; nhm->resvd = 0; if (nla_put_u32(skb, NHA_ID, nh->id)) goto nla_put_failure; if (nh->is_group) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); u32 resp_op_flags = 0; if (nhg->fdb_nh && nla_put_flag(skb, NHA_FDB)) goto nla_put_failure; if (nla_put_nh_group(skb, nh, op_flags, &resp_op_flags) || nla_put_u32(skb, NHA_OP_FLAGS, resp_op_flags)) goto nla_put_failure; goto out; } nhi = rtnl_dereference(nh->nh_info); nhm->nh_family = nhi->family; if (nhi->reject_nh) { if (nla_put_flag(skb, NHA_BLACKHOLE)) goto nla_put_failure; goto out; } else if (nhi->fdb_nh) { if (nla_put_flag(skb, NHA_FDB)) goto nla_put_failure; } else { const struct net_device *dev; dev = nhi->fib_nhc.nhc_dev; if (dev && nla_put_u32(skb, NHA_OIF, dev->ifindex)) goto nla_put_failure; } nhm->nh_scope = nhi->fib_nhc.nhc_scope; switch (nhi->family) { case AF_INET: fib_nh = &nhi->fib_nh; if (fib_nh->fib_nh_gw_family && nla_put_be32(skb, NHA_GATEWAY, fib_nh->fib_nh_gw4)) goto nla_put_failure; break; case AF_INET6: fib6_nh = &nhi->fib6_nh; if (fib6_nh->fib_nh_gw_family && nla_put_in6_addr(skb, NHA_GATEWAY, &fib6_nh->fib_nh_gw6)) goto nla_put_failure; break; } if (nhi->fib_nhc.nhc_lwtstate && lwtunnel_fill_encap(skb, nhi->fib_nhc.nhc_lwtstate, NHA_ENCAP, NHA_ENCAP_TYPE) < 0) goto nla_put_failure; out: nlmsg_end(skb, nlh); return 0; nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static size_t nh_nlmsg_size_grp_res(struct nh_group *nhg) { return nla_total_size(0) + /* NHA_RES_GROUP */ nla_total_size(2) + /* NHA_RES_GROUP_BUCKETS */ nla_total_size(4) + /* NHA_RES_GROUP_IDLE_TIMER */ nla_total_size(4) + /* NHA_RES_GROUP_UNBALANCED_TIMER */ nla_total_size_64bit(8);/* NHA_RES_GROUP_UNBALANCED_TIME */ } static size_t nh_nlmsg_size_grp(struct nexthop *nh) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); size_t sz = sizeof(struct nexthop_grp) * nhg->num_nh; size_t tot = nla_total_size(sz) + nla_total_size(2); /* NHA_GROUP_TYPE */ if (nhg->resilient) tot += nh_nlmsg_size_grp_res(nhg); return tot; } static size_t nh_nlmsg_size_single(struct nexthop *nh) { struct nh_info *nhi = rtnl_dereference(nh->nh_info); size_t sz; /* covers NHA_BLACKHOLE since NHA_OIF and BLACKHOLE * are mutually exclusive */ sz = nla_total_size(4); /* NHA_OIF */ switch (nhi->family) { case AF_INET: if (nhi->fib_nh.fib_nh_gw_family) sz += nla_total_size(4); /* NHA_GATEWAY */ break; case AF_INET6: /* NHA_GATEWAY */ if (nhi->fib6_nh.fib_nh_gw_family) sz += nla_total_size(sizeof(const struct in6_addr)); break; } if (nhi->fib_nhc.nhc_lwtstate) { sz += lwtunnel_get_encap_size(nhi->fib_nhc.nhc_lwtstate); sz += nla_total_size(2); /* NHA_ENCAP_TYPE */ } return sz; } static size_t nh_nlmsg_size(struct nexthop *nh) { size_t sz = NLMSG_ALIGN(sizeof(struct nhmsg)); sz += nla_total_size(4); /* NHA_ID */ if (nh->is_group) sz += nh_nlmsg_size_grp(nh) + nla_total_size(4) + /* NHA_OP_FLAGS */ 0; else sz += nh_nlmsg_size_single(nh); return sz; } static void nexthop_notify(int event, struct nexthop *nh, struct nl_info *info) { unsigned int nlflags = info->nlh ? info->nlh->nlmsg_flags : 0; u32 seq = info->nlh ? info->nlh->nlmsg_seq : 0; struct sk_buff *skb; int err = -ENOBUFS; skb = nlmsg_new(nh_nlmsg_size(nh), gfp_any()); if (!skb) goto errout; err = nh_fill_node(skb, nh, event, info->portid, seq, nlflags, 0); if (err < 0) { /* -EMSGSIZE implies BUG in nh_nlmsg_size() */ WARN_ON(err == -EMSGSIZE); kfree_skb(skb); goto errout; } rtnl_notify(skb, info->nl_net, info->portid, RTNLGRP_NEXTHOP, info->nlh, gfp_any()); return; errout: rtnl_set_sk_err(info->nl_net, RTNLGRP_NEXTHOP, err); } static unsigned long nh_res_bucket_used_time(const struct nh_res_bucket *bucket) { return (unsigned long)atomic_long_read(&bucket->used_time); } static unsigned long nh_res_bucket_idle_point(const struct nh_res_table *res_table, const struct nh_res_bucket *bucket, unsigned long now) { unsigned long time = nh_res_bucket_used_time(bucket); /* Bucket was not used since it was migrated. The idle time is now. */ if (time == bucket->migrated_time) return now; return time + res_table->idle_timer; } static unsigned long nh_res_table_unb_point(const struct nh_res_table *res_table) { return res_table->unbalanced_since + res_table->unbalanced_timer; } static void nh_res_bucket_set_idle(const struct nh_res_table *res_table, struct nh_res_bucket *bucket) { unsigned long now = jiffies; atomic_long_set(&bucket->used_time, (long)now); bucket->migrated_time = now; } static void nh_res_bucket_set_busy(struct nh_res_bucket *bucket) { atomic_long_set(&bucket->used_time, (long)jiffies); } static clock_t nh_res_bucket_idle_time(const struct nh_res_bucket *bucket) { unsigned long used_time = nh_res_bucket_used_time(bucket); return jiffies_delta_to_clock_t(jiffies - used_time); } static int nh_fill_res_bucket(struct sk_buff *skb, struct nexthop *nh, struct nh_res_bucket *bucket, u16 bucket_index, int event, u32 portid, u32 seq, unsigned int nlflags, struct netlink_ext_ack *extack) { struct nh_grp_entry *nhge = nh_res_dereference(bucket->nh_entry); struct nlmsghdr *nlh; struct nlattr *nest; struct nhmsg *nhm; nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nhm), nlflags); if (!nlh) return -EMSGSIZE; nhm = nlmsg_data(nlh); nhm->nh_family = AF_UNSPEC; nhm->nh_flags = bucket->nh_flags; nhm->nh_protocol = nh->protocol; nhm->nh_scope = 0; nhm->resvd = 0; if (nla_put_u32(skb, NHA_ID, nh->id)) goto nla_put_failure; nest = nla_nest_start(skb, NHA_RES_BUCKET); if (!nest) goto nla_put_failure; if (nla_put_u16(skb, NHA_RES_BUCKET_INDEX, bucket_index) || nla_put_u32(skb, NHA_RES_BUCKET_NH_ID, nhge->nh->id) || nla_put_u64_64bit(skb, NHA_RES_BUCKET_IDLE_TIME, nh_res_bucket_idle_time(bucket), NHA_RES_BUCKET_PAD)) goto nla_put_failure_nest; nla_nest_end(skb, nest); nlmsg_end(skb, nlh); return 0; nla_put_failure_nest: nla_nest_cancel(skb, nest); nla_put_failure: nlmsg_cancel(skb, nlh); return -EMSGSIZE; } static void nexthop_bucket_notify(struct nh_res_table *res_table, u16 bucket_index) { struct nh_res_bucket *bucket = &res_table->nh_buckets[bucket_index]; struct nh_grp_entry *nhge = nh_res_dereference(bucket->nh_entry); struct nexthop *nh = nhge->nh_parent; struct sk_buff *skb; int err = -ENOBUFS; skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) goto errout; err = nh_fill_res_bucket(skb, nh, bucket, bucket_index, RTM_NEWNEXTHOPBUCKET, 0, 0, NLM_F_REPLACE, NULL); if (err < 0) { kfree_skb(skb); goto errout; } rtnl_notify(skb, nh->net, 0, RTNLGRP_NEXTHOP, NULL, GFP_KERNEL); return; errout: rtnl_set_sk_err(nh->net, RTNLGRP_NEXTHOP, err); } static bool valid_group_nh(struct nexthop *nh, unsigned int npaths, bool *is_fdb, struct netlink_ext_ack *extack) { if (nh->is_group) { struct nh_group *nhg = rtnl_dereference(nh->nh_grp); /* Nesting groups within groups is not supported. */ if (nhg->hash_threshold) { NL_SET_ERR_MSG(extack, "Hash-threshold group can not be a nexthop within a group"); return false; } if (nhg->resilient) { NL_SET_ERR_MSG(extack, "Resilient group can not be a nexthop within a group"); return false; } *is_fdb = nhg->fdb_nh; } else { struct nh_info *nhi = rtnl_dereference(nh->nh_info); if (nhi->reject_nh && npaths > 1) { NL_SET_ERR_MSG(extack, "Blackhole nexthop can not be used in a group with more than 1 path"); return false; } *is_fdb = nhi->fdb_nh; } return true; } static int nh_check_attr_fdb_group(struct nexthop *nh, u8 *nh_family, struct netlink_ext_ack *extack) { struct nh_info *nhi; nhi = rtnl_dereference(nh->nh_info); if (!nhi->fdb_nh) { NL_SET_ERR_MSG(extack, "FDB nexthop group can only have fdb nexthops"); return -EINVAL; } if (*nh_family == AF_UNSPEC) { *nh_family = nhi->family; } else if (*nh_family != nhi->family) { NL_SET_ERR_MSG(extack, "FDB nexthop group cannot have mixed family nexthops"); return -EINVAL; } return 0; } static int nh_check_attr_group(struct net *net, struct nlattr *tb[], size_t tb_size, u16 nh_grp_type, struct netlink_ext_ack *extack) { unsigned int len = nla_len(tb[NHA_GROUP]); u8 nh_family = AF_UNSPEC; struct nexthop_grp *nhg; unsigned int i, j; u8 nhg_fdb = 0; if (!len || len & (sizeof(struct nexthop_grp) - 1)) { NL_SET_ERR_MSG(extack, "Invalid length for nexthop group attribute"); return -EINVAL; } /* convert len to number of nexthop ids */ len /= sizeof(*nhg); nhg = nla_data(tb[NHA_GROUP]); for (i = 0; i < len; ++i) { if (nhg[i].resvd2) { NL_SET_ERR_MSG(extack, "Reserved field in nexthop_grp must be 0"); return -EINVAL; } if (nexthop_grp_weight(&nhg[i]) == 0) { /* 0xffff got passed in, representing weight of 0x10000, * which is too heavy. */ NL_SET_ERR_MSG(extack, "Invalid value for weight"); return -EINVAL; } for (j = i + 1; j < len; ++j) { if (nhg[i].id == nhg[j].id) { NL_SET_ERR_MSG(extack, "Nexthop id can not be used twice in a group"); return -EINVAL; } } } if (tb[NHA_FDB]) nhg_fdb = 1; nhg = nla_data(tb[NHA_GROUP]); for (i = 0; i < len; ++i) { struct nexthop *nh; bool is_fdb_nh; nh = nexthop_find_by_id(net, nhg[i].id); if (!nh) { NL_SET_ERR_MSG(extack, "Invalid nexthop id"); return -EINVAL; } if (!valid_group_nh(nh, len, &is_fdb_nh, extack)) return -EINVAL; if (nhg_fdb && nh_check_attr_fdb_group(nh, &nh_family, extack)) return -EINVAL; if (!nhg_fdb && is_fdb_nh) { NL_SET_ERR_MSG(extack, "Non FDB nexthop group cannot have fdb nexthops"); return -EINVAL; } } for (i = NHA_GROUP_TYPE + 1; i < tb_size; ++i) { if (!tb[i]) continue; switch (i) { case NHA_HW_STATS_ENABLE: case NHA_FDB: continue; case NHA_RES_GROUP: if (nh_grp_type == NEXTHOP_GRP_TYPE_RES) continue; break; } NL_SET_ERR_MSG(extack, "No other attributes can be set in nexthop groups"); return -EINVAL; } return 0; } static bool ipv6_good_nh(const struct fib6_nh *nh) { int state = NUD_REACHABLE; struct neighbour *n; rcu_read_lock(); n = __ipv6_neigh_lookup_noref_stub(nh->fib_nh_dev, &nh->fib_nh_gw6); if (n) state = READ_ONCE(n->nud_state); rcu_read_unlock(); return !!(state & NUD_VALID); } static bool ipv4_good_nh(const struct fib_nh *nh) { int state = NUD_REACHABLE; struct neighbour *n; rcu_read_lock(); n = __ipv4_neigh_lookup_noref(nh->fib_nh_dev, (__force u32)nh->fib_nh_gw4); if (n) state = READ_ONCE(n->nud_state); rcu_read_unlock(); return !!(state & NUD_VALID); } static bool nexthop_is_good_nh(const struct nexthop *nh) { struct nh_info *nhi = rcu_dereference(nh->nh_info); switch (nhi->family) { case AF_INET: return ipv4_good_nh(&nhi->fib_nh); case AF_INET6: return ipv6_good_nh(&nhi->fib6_nh); } return false; } static struct nexthop *nexthop_select_path_fdb(struct nh_group *nhg, int hash) { int i; for (i = 0; i < nhg->num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; if (hash > atomic_read(&nhge->hthr.upper_bound)) continue; nh_grp_entry_stats_inc(nhge); return nhge->nh; } WARN_ON_ONCE(1); return NULL; } static struct nexthop *nexthop_select_path_hthr(struct nh_group *nhg, int hash) { struct nh_grp_entry *nhge0 = NULL; int i; if (nhg->fdb_nh) return nexthop_select_path_fdb(nhg, hash); for (i = 0; i < nhg->num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; /* nexthops always check if it is good and does * not rely on a sysctl for this behavior */ if (!nexthop_is_good_nh(nhge->nh)) continue; if (!nhge0) nhge0 = nhge; if (hash > atomic_read(&nhge->hthr.upper_bound)) continue; nh_grp_entry_stats_inc(nhge); return nhge->nh; } if (!nhge0) nhge0 = &nhg->nh_entries[0]; nh_grp_entry_stats_inc(nhge0); return nhge0->nh; } static struct nexthop *nexthop_select_path_res(struct nh_group *nhg, int hash) { struct nh_res_table *res_table = rcu_dereference(nhg->res_table); u16 bucket_index = hash % res_table->num_nh_buckets; struct nh_res_bucket *bucket; struct nh_grp_entry *nhge; /* nexthop_select_path() is expected to return a non-NULL value, so * skip protocol validation and just hand out whatever there is. */ bucket = &res_table->nh_buckets[bucket_index]; nh_res_bucket_set_busy(bucket); nhge = rcu_dereference(bucket->nh_entry); nh_grp_entry_stats_inc(nhge); return nhge->nh; } struct nexthop *nexthop_select_path(struct nexthop *nh, int hash) { struct nh_group *nhg; if (!nh->is_group) return nh; nhg = rcu_dereference(nh->nh_grp); if (nhg->hash_threshold) return nexthop_select_path_hthr(nhg, hash); else if (nhg->resilient) return nexthop_select_path_res(nhg, hash); /* Unreachable. */ return NULL; } EXPORT_SYMBOL_GPL(nexthop_select_path); int nexthop_for_each_fib6_nh(struct nexthop *nh, int (*cb)(struct fib6_nh *nh, void *arg), void *arg) { struct nh_info *nhi; int err; if (nh->is_group) { struct nh_group *nhg; int i; nhg = rcu_dereference_rtnl(nh->nh_grp); for (i = 0; i < nhg->num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; nhi = rcu_dereference_rtnl(nhge->nh->nh_info); err = cb(&nhi->fib6_nh, arg); if (err) return err; } } else { nhi = rcu_dereference_rtnl(nh->nh_info); err = cb(&nhi->fib6_nh, arg); if (err) return err; } return 0; } EXPORT_SYMBOL_GPL(nexthop_for_each_fib6_nh); static int check_src_addr(const struct in6_addr *saddr, struct netlink_ext_ack *extack) { if (!ipv6_addr_any(saddr)) { NL_SET_ERR_MSG(extack, "IPv6 routes using source address can not use nexthop objects"); return -EINVAL; } return 0; } int fib6_check_nexthop(struct nexthop *nh, struct fib6_config *cfg, struct netlink_ext_ack *extack) { struct nh_info *nhi; bool is_fdb_nh; /* fib6_src is unique to a fib6_info and limits the ability to cache * routes in fib6_nh within a nexthop that is potentially shared * across multiple fib entries. If the config wants to use source * routing it can not use nexthop objects. mlxsw also does not allow * fib6_src on routes. */ if (cfg && check_src_addr(&cfg->fc_src, extack) < 0) return -EINVAL; if (nh->is_group) { struct nh_group *nhg; nhg = rtnl_dereference(nh->nh_grp); if (nhg->has_v4) goto no_v4_nh; is_fdb_nh = nhg->fdb_nh; } else { nhi = rtnl_dereference(nh->nh_info); if (nhi->family == AF_INET) goto no_v4_nh; is_fdb_nh = nhi->fdb_nh; } if (is_fdb_nh) { NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop"); return -EINVAL; } return 0; no_v4_nh: NL_SET_ERR_MSG(extack, "IPv6 routes can not use an IPv4 nexthop"); return -EINVAL; } EXPORT_SYMBOL_GPL(fib6_check_nexthop); /* if existing nexthop has ipv6 routes linked to it, need * to verify this new spec works with ipv6 */ static int fib6_check_nh_list(struct nexthop *old, struct nexthop *new, struct netlink_ext_ack *extack) { struct fib6_info *f6i; if (list_empty(&old->f6i_list)) return 0; list_for_each_entry(f6i, &old->f6i_list, nh_list) { if (check_src_addr(&f6i->fib6_src.addr, extack) < 0) return -EINVAL; } return fib6_check_nexthop(new, NULL, extack); } static int nexthop_check_scope(struct nh_info *nhi, u8 scope, struct netlink_ext_ack *extack) { if (scope == RT_SCOPE_HOST && nhi->fib_nhc.nhc_gw_family) { NL_SET_ERR_MSG(extack, "Route with host scope can not have a gateway"); return -EINVAL; } if (nhi->fib_nhc.nhc_flags & RTNH_F_ONLINK && scope >= RT_SCOPE_LINK) { NL_SET_ERR_MSG(extack, "Scope mismatch with nexthop"); return -EINVAL; } return 0; } /* Invoked by fib add code to verify nexthop by id is ok with * config for prefix; parts of fib_check_nh not done when nexthop * object is used. */ int fib_check_nexthop(struct nexthop *nh, u8 scope, struct netlink_ext_ack *extack) { struct nh_info *nhi; int err = 0; if (nh->is_group) { struct nh_group *nhg; nhg = rtnl_dereference(nh->nh_grp); if (nhg->fdb_nh) { NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop"); err = -EINVAL; goto out; } if (scope == RT_SCOPE_HOST) { NL_SET_ERR_MSG(extack, "Route with host scope can not have multiple nexthops"); err = -EINVAL; goto out; } /* all nexthops in a group have the same scope */ nhi = rtnl_dereference(nhg->nh_entries[0].nh->nh_info); err = nexthop_check_scope(nhi, scope, extack); } else { nhi = rtnl_dereference(nh->nh_info); if (nhi->fdb_nh) { NL_SET_ERR_MSG(extack, "Route cannot point to a fdb nexthop"); err = -EINVAL; goto out; } err = nexthop_check_scope(nhi, scope, extack); } out: return err; } static int fib_check_nh_list(struct nexthop *old, struct nexthop *new, struct netlink_ext_ack *extack) { struct fib_info *fi; list_for_each_entry(fi, &old->fi_list, nh_list) { int err; err = fib_check_nexthop(new, fi->fib_scope, extack); if (err) return err; } return 0; } static bool nh_res_nhge_is_balanced(const struct nh_grp_entry *nhge) { return nhge->res.count_buckets == nhge->res.wants_buckets; } static bool nh_res_nhge_is_ow(const struct nh_grp_entry *nhge) { return nhge->res.count_buckets > nhge->res.wants_buckets; } static bool nh_res_nhge_is_uw(const struct nh_grp_entry *nhge) { return nhge->res.count_buckets < nhge->res.wants_buckets; } static bool nh_res_table_is_balanced(const struct nh_res_table *res_table) { return list_empty(&res_table->uw_nh_entries); } static void nh_res_bucket_unset_nh(struct nh_res_bucket *bucket) { struct nh_grp_entry *nhge; if (bucket->occupied) { nhge = nh_res_dereference(bucket->nh_entry); nhge->res.count_buckets--; bucket->occupied = false; } } static void nh_res_bucket_set_nh(struct nh_res_bucket *bucket, struct nh_grp_entry *nhge) { nh_res_bucket_unset_nh(bucket); bucket->occupied = true; rcu_assign_pointer(bucket->nh_entry, nhge); nhge->res.count_buckets++; } static bool nh_res_bucket_should_migrate(struct nh_res_table *res_table, struct nh_res_bucket *bucket, unsigned long *deadline, bool *force) { unsigned long now = jiffies; struct nh_grp_entry *nhge; unsigned long idle_point; if (!bucket->occupied) { /* The bucket is not occupied, its NHGE pointer is either * NULL or obsolete. We _have to_ migrate: set force. */ *force = true; return true; } nhge = nh_res_dereference(bucket->nh_entry); /* If the bucket is populated by an underweight or balanced * nexthop, do not migrate. */ if (!nh_res_nhge_is_ow(nhge)) return false; /* At this point we know that the bucket is populated with an * overweight nexthop. It needs to be migrated to a new nexthop if * the idle timer of unbalanced timer expired. */ idle_point = nh_res_bucket_idle_point(res_table, bucket, now); if (time_after_eq(now, idle_point)) { /* The bucket is idle. We _can_ migrate: unset force. */ *force = false; return true; } /* Unbalanced timer of 0 means "never force". */ if (res_table->unbalanced_timer) { unsigned long unb_point; unb_point = nh_res_table_unb_point(res_table); if (time_after(now, unb_point)) { /* The bucket is not idle, but the unbalanced timer * expired. We _can_ migrate, but set force anyway, * so that drivers know to ignore activity reports * from the HW. */ *force = true; return true; } nh_res_time_set_deadline(unb_point, deadline); } nh_res_time_set_deadline(idle_point, deadline); return false; } static bool nh_res_bucket_migrate(struct nh_res_table *res_table, u16 bucket_index, bool notify, bool notify_nl, bool force) { struct nh_res_bucket *bucket = &res_table->nh_buckets[bucket_index]; struct nh_grp_entry *new_nhge; struct netlink_ext_ack extack; int err; new_nhge = list_first_entry_or_null(&res_table->uw_nh_entries, struct nh_grp_entry, res.uw_nh_entry); if (WARN_ON_ONCE(!new_nhge)) /* If this function is called, "bucket" is either not * occupied, or it belongs to a next hop that is * overweight. In either case, there ought to be a * corresponding underweight next hop. */ return false; if (notify) { struct nh_grp_entry *old_nhge; old_nhge = nh_res_dereference(bucket->nh_entry); err = call_nexthop_res_bucket_notifiers(res_table->net, res_table->nhg_id, bucket_index, force, old_nhge->nh, new_nhge->nh, &extack); if (err) { pr_err_ratelimited("%s\n", extack._msg); if (!force) return false; /* It is not possible to veto a forced replacement, so * just clear the hardware flags from the nexthop * bucket to indicate to user space that this bucket is * not correctly populated in hardware. */ bucket->nh_flags &= ~(RTNH_F_OFFLOAD | RTNH_F_TRAP); } } nh_res_bucket_set_nh(bucket, new_nhge); nh_res_bucket_set_idle(res_table, bucket); if (notify_nl) nexthop_bucket_notify(res_table, bucket_index); if (nh_res_nhge_is_balanced(new_nhge)) list_del(&new_nhge->res.uw_nh_entry); return true; } #define NH_RES_UPKEEP_DW_MINIMUM_INTERVAL (HZ / 2) static void nh_res_table_upkeep(struct nh_res_table *res_table, bool notify, bool notify_nl) { unsigned long now = jiffies; unsigned long deadline; u16 i; /* Deadline is the next time that upkeep should be run. It is the * earliest time at which one of the buckets might be migrated. * Start at the most pessimistic estimate: either unbalanced_timer * from now, or if there is none, idle_timer from now. For each * encountered time point, call nh_res_time_set_deadline() to * refine the estimate. */ if (res_table->unbalanced_timer) deadline = now + res_table->unbalanced_timer; else deadline = now + res_table->idle_timer; for (i = 0; i < res_table->num_nh_buckets; i++) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; bool force; if (nh_res_bucket_should_migrate(res_table, bucket, &deadline, &force)) { if (!nh_res_bucket_migrate(res_table, i, notify, notify_nl, force)) { unsigned long idle_point; /* A driver can override the migration * decision if the HW reports that the * bucket is actually not idle. Therefore * remark the bucket as busy again and * update the deadline. */ nh_res_bucket_set_busy(bucket); idle_point = nh_res_bucket_idle_point(res_table, bucket, now); nh_res_time_set_deadline(idle_point, &deadline); } } } /* If the group is still unbalanced, schedule the next upkeep to * either the deadline computed above, or the minimum deadline, * whichever comes later. */ if (!nh_res_table_is_balanced(res_table)) { unsigned long now = jiffies; unsigned long min_deadline; min_deadline = now + NH_RES_UPKEEP_DW_MINIMUM_INTERVAL; if (time_before(deadline, min_deadline)) deadline = min_deadline; queue_delayed_work(system_power_efficient_wq, &res_table->upkeep_dw, deadline - now); } } static void nh_res_table_upkeep_dw(struct work_struct *work) { struct delayed_work *dw = to_delayed_work(work); struct nh_res_table *res_table; res_table = container_of(dw, struct nh_res_table, upkeep_dw); nh_res_table_upkeep(res_table, true, true); } static void nh_res_table_cancel_upkeep(struct nh_res_table *res_table) { cancel_delayed_work_sync(&res_table->upkeep_dw); } static void nh_res_group_rebalance(struct nh_group *nhg, struct nh_res_table *res_table) { u16 prev_upper_bound = 0; u32 total = 0; u32 w = 0; int i; INIT_LIST_HEAD(&res_table->uw_nh_entries); for (i = 0; i < nhg->num_nh; ++i) total += nhg->nh_entries[i].weight; for (i = 0; i < nhg->num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; u16 upper_bound; u64 btw; w += nhge->weight; btw = ((u64)res_table->num_nh_buckets) * w; upper_bound = DIV_ROUND_CLOSEST_ULL(btw, total); nhge->res.wants_buckets = upper_bound - prev_upper_bound; prev_upper_bound = upper_bound; if (nh_res_nhge_is_uw(nhge)) { if (list_empty(&res_table->uw_nh_entries)) res_table->unbalanced_since = jiffies; list_add(&nhge->res.uw_nh_entry, &res_table->uw_nh_entries); } } } /* Migrate buckets in res_table so that they reference NHGE's from NHG with * the right NH ID. Set those buckets that do not have a corresponding NHGE * entry in NHG as not occupied. */ static void nh_res_table_migrate_buckets(struct nh_res_table *res_table, struct nh_group *nhg) { u16 i; for (i = 0; i < res_table->num_nh_buckets; i++) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; u32 id = rtnl_dereference(bucket->nh_entry)->nh->id; bool found = false; int j; for (j = 0; j < nhg->num_nh; j++) { struct nh_grp_entry *nhge = &nhg->nh_entries[j]; if (nhge->nh->id == id) { nh_res_bucket_set_nh(bucket, nhge); found = true; break; } } if (!found) nh_res_bucket_unset_nh(bucket); } } static void replace_nexthop_grp_res(struct nh_group *oldg, struct nh_group *newg) { /* For NH group replacement, the new NHG might only have a stub * hash table with 0 buckets, because the number of buckets was not * specified. For NH removal, oldg and newg both reference the same * res_table. So in any case, in the following, we want to work * with oldg->res_table. */ struct nh_res_table *old_res_table = rtnl_dereference(oldg->res_table); unsigned long prev_unbalanced_since = old_res_table->unbalanced_since; bool prev_has_uw = !list_empty(&old_res_table->uw_nh_entries); nh_res_table_cancel_upkeep(old_res_table); nh_res_table_migrate_buckets(old_res_table, newg); nh_res_group_rebalance(newg, old_res_table); if (prev_has_uw && !list_empty(&old_res_table->uw_nh_entries)) old_res_table->unbalanced_since = prev_unbalanced_since; nh_res_table_upkeep(old_res_table, true, false); } static void nh_hthr_group_rebalance(struct nh_group *nhg) { u32 total = 0; u32 w = 0; int i; for (i = 0; i < nhg->num_nh; ++i) total += nhg->nh_entries[i].weight; for (i = 0; i < nhg->num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; u32 upper_bound; w += nhge->weight; upper_bound = DIV_ROUND_CLOSEST_ULL((u64)w << 31, total) - 1; atomic_set(&nhge->hthr.upper_bound, upper_bound); } } static void remove_nh_grp_entry(struct net *net, struct nh_grp_entry *nhge, struct nl_info *nlinfo) { struct nh_grp_entry *nhges, *new_nhges; struct nexthop *nhp = nhge->nh_parent; struct netlink_ext_ack extack; struct nexthop *nh = nhge->nh; struct nh_group *nhg, *newg; int i, j, err; WARN_ON(!nh); nhg = rtnl_dereference(nhp->nh_grp); newg = nhg->spare; /* last entry, keep it visible and remove the parent */ if (nhg->num_nh == 1) { remove_nexthop(net, nhp, nlinfo); return; } newg->has_v4 = false; newg->is_multipath = nhg->is_multipath; newg->hash_threshold = nhg->hash_threshold; newg->resilient = nhg->resilient; newg->fdb_nh = nhg->fdb_nh; newg->num_nh = nhg->num_nh; /* copy old entries to new except the one getting removed */ nhges = nhg->nh_entries; new_nhges = newg->nh_entries; for (i = 0, j = 0; i < nhg->num_nh; ++i) { struct nh_info *nhi; /* current nexthop getting removed */ if (nhg->nh_entries[i].nh == nh) { newg->num_nh--; continue; } nhi = rtnl_dereference(nhges[i].nh->nh_info); if (nhi->family == AF_INET) newg->has_v4 = true; list_del(&nhges[i].nh_list); new_nhges[j].stats = nhges[i].stats; new_nhges[j].nh_parent = nhges[i].nh_parent; new_nhges[j].nh = nhges[i].nh; new_nhges[j].weight = nhges[i].weight; list_add(&new_nhges[j].nh_list, &new_nhges[j].nh->grp_list); j++; } if (newg->hash_threshold) nh_hthr_group_rebalance(newg); else if (newg->resilient) replace_nexthop_grp_res(nhg, newg); rcu_assign_pointer(nhp->nh_grp, newg); list_del(&nhge->nh_list); free_percpu(nhge->stats); nexthop_put(nhge->nh); /* Removal of a NH from a resilient group is notified through * bucket notifications. */ if (newg->hash_threshold) { err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, nhp, &extack); if (err) pr_err("%s\n", extack._msg); } if (nlinfo) nexthop_notify(RTM_NEWNEXTHOP, nhp, nlinfo); } static void remove_nexthop_from_groups(struct net *net, struct nexthop *nh, struct nl_info *nlinfo) { struct nh_grp_entry *nhge, *tmp; list_for_each_entry_safe(nhge, tmp, &nh->grp_list, nh_list) remove_nh_grp_entry(net, nhge, nlinfo); /* make sure all see the newly published array before releasing rtnl */ synchronize_net(); } static void remove_nexthop_group(struct nexthop *nh, struct nl_info *nlinfo) { struct nh_group *nhg = rcu_dereference_rtnl(nh->nh_grp); struct nh_res_table *res_table; int i, num_nh = nhg->num_nh; for (i = 0; i < num_nh; ++i) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; if (WARN_ON(!nhge->nh)) continue; list_del_init(&nhge->nh_list); } if (nhg->resilient) { res_table = rtnl_dereference(nhg->res_table); nh_res_table_cancel_upkeep(res_table); } } /* not called for nexthop replace */ static void __remove_nexthop_fib(struct net *net, struct nexthop *nh) { struct fib6_info *f6i, *tmp; bool do_flush = false; struct fib_info *fi; list_for_each_entry(fi, &nh->fi_list, nh_list) { fi->fib_flags |= RTNH_F_DEAD; do_flush = true; } if (do_flush) fib_flush(net); /* ip6_del_rt removes the entry from this list hence the _safe */ list_for_each_entry_safe(f6i, tmp, &nh->f6i_list, nh_list) { /* __ip6_del_rt does a release, so do a hold here */ fib6_info_hold(f6i); ipv6_stub->ip6_del_rt(net, f6i, !READ_ONCE(net->ipv4.sysctl_nexthop_compat_mode)); } } static void __remove_nexthop(struct net *net, struct nexthop *nh, struct nl_info *nlinfo) { __remove_nexthop_fib(net, nh); if (nh->is_group) { remove_nexthop_group(nh, nlinfo); } else { struct nh_info *nhi; nhi = rtnl_dereference(nh->nh_info); if (nhi->fib_nhc.nhc_dev) hlist_del(&nhi->dev_hash); remove_nexthop_from_groups(net, nh, nlinfo); } } static void remove_nexthop(struct net *net, struct nexthop *nh, struct nl_info *nlinfo) { call_nexthop_notifiers(net, NEXTHOP_EVENT_DEL, nh, NULL); /* remove from the tree */ rb_erase(&nh->rb_node, &net->nexthop.rb_root); if (nlinfo) nexthop_notify(RTM_DELNEXTHOP, nh, nlinfo); __remove_nexthop(net, nh, nlinfo); nh_base_seq_inc(net); nexthop_put(nh); } /* if any FIB entries reference this nexthop, any dst entries * need to be regenerated */ static void nh_rt_cache_flush(struct net *net, struct nexthop *nh, struct nexthop *replaced_nh) { struct fib6_info *f6i; struct nh_group *nhg; int i; if (!list_empty(&nh->fi_list)) rt_cache_flush(net); list_for_each_entry(f6i, &nh->f6i_list, nh_list) ipv6_stub->fib6_update_sernum(net, f6i); /* if an IPv6 group was replaced, we have to release all old * dsts to make sure all refcounts are released */ if (!replaced_nh->is_group) return; nhg = rtnl_dereference(replaced_nh->nh_grp); for (i = 0; i < nhg->num_nh; i++) { struct nh_grp_entry *nhge = &nhg->nh_entries[i]; struct nh_info *nhi = rtnl_dereference(nhge->nh->nh_info); if (nhi->family == AF_INET6) ipv6_stub->fib6_nh_release_dsts(&nhi->fib6_nh); } } static int replace_nexthop_grp(struct net *net, struct nexthop *old, struct nexthop *new, const struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nh_res_table *tmp_table = NULL; struct nh_res_table *new_res_table; struct nh_res_table *old_res_table; struct nh_group *oldg, *newg; int i, err; if (!new->is_group) { NL_SET_ERR_MSG(extack, "Can not replace a nexthop group with a nexthop."); return -EINVAL; } oldg = rtnl_dereference(old->nh_grp); newg = rtnl_dereference(new->nh_grp); if (newg->hash_threshold != oldg->hash_threshold) { NL_SET_ERR_MSG(extack, "Can not replace a nexthop group with one of a different type."); return -EINVAL; } if (newg->hash_threshold) { err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new, extack); if (err) return err; } else if (newg->resilient) { new_res_table = rtnl_dereference(newg->res_table); old_res_table = rtnl_dereference(oldg->res_table); /* Accept if num_nh_buckets was not given, but if it was * given, demand that the value be correct. */ if (cfg->nh_grp_res_has_num_buckets && cfg->nh_grp_res_num_buckets != old_res_table->num_nh_buckets) { NL_SET_ERR_MSG(extack, "Can not change number of buckets of a resilient nexthop group."); return -EINVAL; } /* Emit a pre-replace notification so that listeners could veto * a potentially unsupported configuration. Otherwise, * individual bucket replacement notifications would need to be * vetoed, which is something that should only happen if the * bucket is currently active. */ err = call_nexthop_res_table_notifiers(net, new, extack); if (err) return err; if (cfg->nh_grp_res_has_idle_timer) old_res_table->idle_timer = cfg->nh_grp_res_idle_timer; if (cfg->nh_grp_res_has_unbalanced_timer) old_res_table->unbalanced_timer = cfg->nh_grp_res_unbalanced_timer; replace_nexthop_grp_res(oldg, newg); tmp_table = new_res_table; rcu_assign_pointer(newg->res_table, old_res_table); rcu_assign_pointer(newg->spare->res_table, old_res_table); } /* update parents - used by nexthop code for cleanup */ for (i = 0; i < newg->num_nh; i++) newg->nh_entries[i].nh_parent = old; rcu_assign_pointer(old->nh_grp, newg); /* Make sure concurrent readers are not using 'oldg' anymore. */ synchronize_net(); if (newg->resilient) { rcu_assign_pointer(oldg->res_table, tmp_table); rcu_assign_pointer(oldg->spare->res_table, tmp_table); } for (i = 0; i < oldg->num_nh; i++) oldg->nh_entries[i].nh_parent = new; rcu_assign_pointer(new->nh_grp, oldg); return 0; } static void nh_group_v4_update(struct nh_group *nhg) { struct nh_grp_entry *nhges; bool has_v4 = false; int i; nhges = nhg->nh_entries; for (i = 0; i < nhg->num_nh; i++) { struct nh_info *nhi; nhi = rtnl_dereference(nhges[i].nh->nh_info); if (nhi->family == AF_INET) has_v4 = true; } nhg->has_v4 = has_v4; } static int replace_nexthop_single_notify_res(struct net *net, struct nh_res_table *res_table, struct nexthop *old, struct nh_info *oldi, struct nh_info *newi, struct netlink_ext_ack *extack) { u32 nhg_id = res_table->nhg_id; int err; u16 i; for (i = 0; i < res_table->num_nh_buckets; i++) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; struct nh_grp_entry *nhge; nhge = rtnl_dereference(bucket->nh_entry); if (nhge->nh == old) { err = __call_nexthop_res_bucket_notifiers(net, nhg_id, i, true, oldi, newi, extack); if (err) goto err_notify; } } return 0; err_notify: while (i-- > 0) { struct nh_res_bucket *bucket = &res_table->nh_buckets[i]; struct nh_grp_entry *nhge; nhge = rtnl_dereference(bucket->nh_entry); if (nhge->nh == old) __call_nexthop_res_bucket_notifiers(net, nhg_id, i, true, newi, oldi, extack); } return err; } static int replace_nexthop_single_notify(struct net *net, struct nexthop *group_nh, struct nexthop *old, struct nh_info *oldi, struct nh_info *newi, struct netlink_ext_ack *extack) { struct nh_group *nhg = rtnl_dereference(group_nh->nh_grp); struct nh_res_table *res_table; if (nhg->hash_threshold) { return call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, group_nh, extack); } else if (nhg->resilient) { res_table = rtnl_dereference(nhg->res_table); return replace_nexthop_single_notify_res(net, res_table, old, oldi, newi, extack); } return -EINVAL; } static int replace_nexthop_single(struct net *net, struct nexthop *old, struct nexthop *new, struct netlink_ext_ack *extack) { u8 old_protocol, old_nh_flags; struct nh_info *oldi, *newi; struct nh_grp_entry *nhge; int err; if (new->is_group) { NL_SET_ERR_MSG(extack, "Can not replace a nexthop with a nexthop group."); return -EINVAL; } err = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new, extack); if (err) return err; /* Hardware flags were set on 'old' as 'new' is not in the red-black * tree. Therefore, inherit the flags from 'old' to 'new'. */ new->nh_flags |= old->nh_flags & (RTNH_F_OFFLOAD | RTNH_F_TRAP); oldi = rtnl_dereference(old->nh_info); newi = rtnl_dereference(new->nh_info); newi->nh_parent = old; oldi->nh_parent = new; old_protocol = old->protocol; old_nh_flags = old->nh_flags; old->protocol = new->protocol; old->nh_flags = new->nh_flags; rcu_assign_pointer(old->nh_info, newi); rcu_assign_pointer(new->nh_info, oldi); /* Send a replace notification for all the groups using the nexthop. */ list_for_each_entry(nhge, &old->grp_list, nh_list) { struct nexthop *nhp = nhge->nh_parent; err = replace_nexthop_single_notify(net, nhp, old, oldi, newi, extack); if (err) goto err_notify; } /* When replacing an IPv4 nexthop with an IPv6 nexthop, potentially * update IPv4 indication in all the groups using the nexthop. */ if (oldi->family == AF_INET && newi->family == AF_INET6) { list_for_each_entry(nhge, &old->grp_list, nh_list) { struct nexthop *nhp = nhge->nh_parent; struct nh_group *nhg; nhg = rtnl_dereference(nhp->nh_grp); nh_group_v4_update(nhg); } } return 0; err_notify: rcu_assign_pointer(new->nh_info, newi); rcu_assign_pointer(old->nh_info, oldi); old->nh_flags = old_nh_flags; old->protocol = old_protocol; oldi->nh_parent = old; newi->nh_parent = new; list_for_each_entry_continue_reverse(nhge, &old->grp_list, nh_list) { struct nexthop *nhp = nhge->nh_parent; replace_nexthop_single_notify(net, nhp, old, newi, oldi, NULL); } call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, old, extack); return err; } static void __nexthop_replace_notify(struct net *net, struct nexthop *nh, struct nl_info *info) { struct fib6_info *f6i; if (!list_empty(&nh->fi_list)) { struct fib_info *fi; /* expectation is a few fib_info per nexthop and then * a lot of routes per fib_info. So mark the fib_info * and then walk the fib tables once */ list_for_each_entry(fi, &nh->fi_list, nh_list) fi->nh_updated = true; fib_info_notify_update(net, info); list_for_each_entry(fi, &nh->fi_list, nh_list) fi->nh_updated = false; } list_for_each_entry(f6i, &nh->f6i_list, nh_list) ipv6_stub->fib6_rt_update(net, f6i, info); } /* send RTM_NEWROUTE with REPLACE flag set for all FIB entries * linked to this nexthop and for all groups that the nexthop * is a member of */ static void nexthop_replace_notify(struct net *net, struct nexthop *nh, struct nl_info *info) { struct nh_grp_entry *nhge; __nexthop_replace_notify(net, nh, info); list_for_each_entry(nhge, &nh->grp_list, nh_list) __nexthop_replace_notify(net, nhge->nh_parent, info); } static int replace_nexthop(struct net *net, struct nexthop *old, struct nexthop *new, const struct nh_config *cfg, struct netlink_ext_ack *extack) { bool new_is_reject = false; struct nh_grp_entry *nhge; int err; /* check that existing FIB entries are ok with the * new nexthop definition */ err = fib_check_nh_list(old, new, extack); if (err) return err; err = fib6_check_nh_list(old, new, extack); if (err) return err; if (!new->is_group) { struct nh_info *nhi = rtnl_dereference(new->nh_info); new_is_reject = nhi->reject_nh; } list_for_each_entry(nhge, &old->grp_list, nh_list) { /* if new nexthop is a blackhole, any groups using this * nexthop cannot have more than 1 path */ if (new_is_reject && nexthop_num_path(nhge->nh_parent) > 1) { NL_SET_ERR_MSG(extack, "Blackhole nexthop can not be a member of a group with more than one path"); return -EINVAL; } err = fib_check_nh_list(nhge->nh_parent, new, extack); if (err) return err; err = fib6_check_nh_list(nhge->nh_parent, new, extack); if (err) return err; } if (old->is_group) err = replace_nexthop_grp(net, old, new, cfg, extack); else err = replace_nexthop_single(net, old, new, extack); if (!err) { nh_rt_cache_flush(net, old, new); __remove_nexthop(net, new, NULL); nexthop_put(new); } return err; } /* called with rtnl_lock held */ static int insert_nexthop(struct net *net, struct nexthop *new_nh, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct rb_node **pp, *parent = NULL, *next; struct rb_root *root = &net->nexthop.rb_root; bool replace = !!(cfg->nlflags & NLM_F_REPLACE); bool create = !!(cfg->nlflags & NLM_F_CREATE); u32 new_id = new_nh->id; int replace_notify = 0; int rc = -EEXIST; pp = &root->rb_node; while (1) { struct nexthop *nh; next = *pp; if (!next) break; parent = next; nh = rb_entry(parent, struct nexthop, rb_node); if (new_id < nh->id) { pp = &next->rb_left; } else if (new_id > nh->id) { pp = &next->rb_right; } else if (replace) { rc = replace_nexthop(net, nh, new_nh, cfg, extack); if (!rc) { new_nh = nh; /* send notification with old nh */ replace_notify = 1; } goto out; } else { /* id already exists and not a replace */ goto out; } } if (replace && !create) { NL_SET_ERR_MSG(extack, "Replace specified without create and no entry exists"); rc = -ENOENT; goto out; } if (new_nh->is_group) { struct nh_group *nhg = rtnl_dereference(new_nh->nh_grp); struct nh_res_table *res_table; if (nhg->resilient) { res_table = rtnl_dereference(nhg->res_table); /* Not passing the number of buckets is OK when * replacing, but not when creating a new group. */ if (!cfg->nh_grp_res_has_num_buckets) { NL_SET_ERR_MSG(extack, "Number of buckets not specified for nexthop group insertion"); rc = -EINVAL; goto out; } nh_res_group_rebalance(nhg, res_table); /* Do not send bucket notifications, we do full * notification below. */ nh_res_table_upkeep(res_table, false, false); } } rb_link_node_rcu(&new_nh->rb_node, parent, pp); rb_insert_color(&new_nh->rb_node, root); /* The initial insertion is a full notification for hash-threshold as * well as resilient groups. */ rc = call_nexthop_notifiers(net, NEXTHOP_EVENT_REPLACE, new_nh, extack); if (rc) rb_erase(&new_nh->rb_node, &net->nexthop.rb_root); out: if (!rc) { nh_base_seq_inc(net); nexthop_notify(RTM_NEWNEXTHOP, new_nh, &cfg->nlinfo); if (replace_notify && READ_ONCE(net->ipv4.sysctl_nexthop_compat_mode)) nexthop_replace_notify(net, new_nh, &cfg->nlinfo); } return rc; } /* rtnl */ /* remove all nexthops tied to a device being deleted */ static void nexthop_flush_dev(struct net_device *dev, unsigned long event) { unsigned int hash = nh_dev_hashfn(dev->ifindex); struct net *net = dev_net(dev); struct hlist_head *head = &net->nexthop.devhash[hash]; struct hlist_node *n; struct nh_info *nhi; hlist_for_each_entry_safe(nhi, n, head, dev_hash) { if (nhi->fib_nhc.nhc_dev != dev) continue; if (nhi->reject_nh && (event == NETDEV_DOWN || event == NETDEV_CHANGE)) continue; remove_nexthop(net, nhi->nh_parent, NULL); } } /* rtnl; called when net namespace is deleted */ static void flush_all_nexthops(struct net *net) { struct rb_root *root = &net->nexthop.rb_root; struct rb_node *node; struct nexthop *nh; while ((node = rb_first(root))) { nh = rb_entry(node, struct nexthop, rb_node); remove_nexthop(net, nh, NULL); cond_resched(); } } static struct nexthop *nexthop_create_group(struct net *net, struct nh_config *cfg) { struct nlattr *grps_attr = cfg->nh_grp; struct nexthop_grp *entry = nla_data(grps_attr); u16 num_nh = nla_len(grps_attr) / sizeof(*entry); struct nh_group *nhg; struct nexthop *nh; int err; int i; if (WARN_ON(!num_nh)) return ERR_PTR(-EINVAL); nh = nexthop_alloc(); if (!nh) return ERR_PTR(-ENOMEM); nh->is_group = 1; nhg = nexthop_grp_alloc(num_nh); if (!nhg) { kfree(nh); return ERR_PTR(-ENOMEM); } /* spare group used for removals */ nhg->spare = nexthop_grp_alloc(num_nh); if (!nhg->spare) { kfree(nhg); kfree(nh); return ERR_PTR(-ENOMEM); } nhg->spare->spare = nhg; for (i = 0; i < nhg->num_nh; ++i) { struct nexthop *nhe; struct nh_info *nhi; nhe = nexthop_find_by_id(net, entry[i].id); if (!nexthop_get(nhe)) { err = -ENOENT; goto out_no_nh; } nhi = rtnl_dereference(nhe->nh_info); if (nhi->family == AF_INET) nhg->has_v4 = true; nhg->nh_entries[i].stats = netdev_alloc_pcpu_stats(struct nh_grp_entry_stats); if (!nhg->nh_entries[i].stats) { err = -ENOMEM; nexthop_put(nhe); goto out_no_nh; } nhg->nh_entries[i].nh = nhe; nhg->nh_entries[i].weight = nexthop_grp_weight(&entry[i]); list_add(&nhg->nh_entries[i].nh_list, &nhe->grp_list); nhg->nh_entries[i].nh_parent = nh; } if (cfg->nh_grp_type == NEXTHOP_GRP_TYPE_MPATH) { nhg->hash_threshold = 1; nhg->is_multipath = true; } else if (cfg->nh_grp_type == NEXTHOP_GRP_TYPE_RES) { struct nh_res_table *res_table; res_table = nexthop_res_table_alloc(net, cfg->nh_id, cfg); if (!res_table) { err = -ENOMEM; goto out_no_nh; } rcu_assign_pointer(nhg->spare->res_table, res_table); rcu_assign_pointer(nhg->res_table, res_table); nhg->resilient = true; nhg->is_multipath = true; } WARN_ON_ONCE(nhg->hash_threshold + nhg->resilient != 1); if (nhg->hash_threshold) nh_hthr_group_rebalance(nhg); if (cfg->nh_fdb) nhg->fdb_nh = 1; if (cfg->nh_hw_stats) nhg->hw_stats = true; rcu_assign_pointer(nh->nh_grp, nhg); return nh; out_no_nh: for (i--; i >= 0; --i) { list_del(&nhg->nh_entries[i].nh_list); free_percpu(nhg->nh_entries[i].stats); nexthop_put(nhg->nh_entries[i].nh); } kfree(nhg->spare); kfree(nhg); kfree(nh); return ERR_PTR(err); } static int nh_create_ipv4(struct net *net, struct nexthop *nh, struct nh_info *nhi, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct fib_nh *fib_nh = &nhi->fib_nh; struct fib_config fib_cfg = { .fc_oif = cfg->nh_ifindex, .fc_gw4 = cfg->gw.ipv4, .fc_gw_family = cfg->gw.ipv4 ? AF_INET : 0, .fc_flags = cfg->nh_flags, .fc_nlinfo = cfg->nlinfo, .fc_encap = cfg->nh_encap, .fc_encap_type = cfg->nh_encap_type, }; u32 tb_id = (cfg->dev ? l3mdev_fib_table(cfg->dev) : RT_TABLE_MAIN); int err; err = fib_nh_init(net, fib_nh, &fib_cfg, 1, extack); if (err) { fib_nh_release(net, fib_nh); goto out; } if (nhi->fdb_nh) goto out; /* sets nh_dev if successful */ err = fib_check_nh(net, fib_nh, tb_id, 0, extack); if (!err) { nh->nh_flags = fib_nh->fib_nh_flags; fib_info_update_nhc_saddr(net, &fib_nh->nh_common, !fib_nh->fib_nh_scope ? 0 : fib_nh->fib_nh_scope - 1); } else { fib_nh_release(net, fib_nh); } out: return err; } static int nh_create_ipv6(struct net *net, struct nexthop *nh, struct nh_info *nhi, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct fib6_nh *fib6_nh = &nhi->fib6_nh; struct fib6_config fib6_cfg = { .fc_table = l3mdev_fib_table(cfg->dev), .fc_ifindex = cfg->nh_ifindex, .fc_gateway = cfg->gw.ipv6, .fc_flags = cfg->nh_flags, .fc_nlinfo = cfg->nlinfo, .fc_encap = cfg->nh_encap, .fc_encap_type = cfg->nh_encap_type, .fc_is_fdb = cfg->nh_fdb, }; int err; if (!ipv6_addr_any(&cfg->gw.ipv6)) fib6_cfg.fc_flags |= RTF_GATEWAY; /* sets nh_dev if successful */ err = ipv6_stub->fib6_nh_init(net, fib6_nh, &fib6_cfg, GFP_KERNEL, extack); if (err) { /* IPv6 is not enabled, don't call fib6_nh_release */ if (err == -EAFNOSUPPORT) goto out; ipv6_stub->fib6_nh_release(fib6_nh); } else { nh->nh_flags = fib6_nh->fib_nh_flags; } out: return err; } static struct nexthop *nexthop_create(struct net *net, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nh_info *nhi; struct nexthop *nh; int err = 0; nh = nexthop_alloc(); if (!nh) return ERR_PTR(-ENOMEM); nhi = kzalloc(sizeof(*nhi), GFP_KERNEL); if (!nhi) { kfree(nh); return ERR_PTR(-ENOMEM); } nh->nh_flags = cfg->nh_flags; nh->net = net; nhi->nh_parent = nh; nhi->family = cfg->nh_family; nhi->fib_nhc.nhc_scope = RT_SCOPE_LINK; if (cfg->nh_fdb) nhi->fdb_nh = 1; if (cfg->nh_blackhole) { nhi->reject_nh = 1; cfg->nh_ifindex = net->loopback_dev->ifindex; } switch (cfg->nh_family) { case AF_INET: err = nh_create_ipv4(net, nh, nhi, cfg, extack); break; case AF_INET6: err = nh_create_ipv6(net, nh, nhi, cfg, extack); break; } if (err) { kfree(nhi); kfree(nh); return ERR_PTR(err); } /* add the entry to the device based hash */ if (!nhi->fdb_nh) nexthop_devhash_add(net, nhi); rcu_assign_pointer(nh->nh_info, nhi); return nh; } /* called with rtnl lock held */ static struct nexthop *nexthop_add(struct net *net, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nexthop *nh; int err; if (cfg->nlflags & NLM_F_REPLACE && !cfg->nh_id) { NL_SET_ERR_MSG(extack, "Replace requires nexthop id"); return ERR_PTR(-EINVAL); } if (!cfg->nh_id) { cfg->nh_id = nh_find_unused_id(net); if (!cfg->nh_id) { NL_SET_ERR_MSG(extack, "No unused id"); return ERR_PTR(-EINVAL); } } if (cfg->nh_grp) nh = nexthop_create_group(net, cfg); else nh = nexthop_create(net, cfg, extack); if (IS_ERR(nh)) return nh; refcount_set(&nh->refcnt, 1); nh->id = cfg->nh_id; nh->protocol = cfg->nh_protocol; nh->net = net; err = insert_nexthop(net, nh, cfg, extack); if (err) { __remove_nexthop(net, nh, NULL); nexthop_put(nh); nh = ERR_PTR(err); } return nh; } static int rtm_nh_get_timer(struct nlattr *attr, unsigned long fallback, unsigned long *timer_p, bool *has_p, struct netlink_ext_ack *extack) { unsigned long timer; u32 value; if (!attr) { *timer_p = fallback; *has_p = false; return 0; } value = nla_get_u32(attr); timer = clock_t_to_jiffies(value); if (timer == ~0UL) { NL_SET_ERR_MSG(extack, "Timer value too large"); return -EINVAL; } *timer_p = timer; *has_p = true; return 0; } static int rtm_to_nh_config_grp_res(struct nlattr *res, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_res_policy_new)] = {}; int err; if (res) { err = nla_parse_nested(tb, ARRAY_SIZE(rtm_nh_res_policy_new) - 1, res, rtm_nh_res_policy_new, extack); if (err < 0) return err; } if (tb[NHA_RES_GROUP_BUCKETS]) { cfg->nh_grp_res_num_buckets = nla_get_u16(tb[NHA_RES_GROUP_BUCKETS]); cfg->nh_grp_res_has_num_buckets = true; if (!cfg->nh_grp_res_num_buckets) { NL_SET_ERR_MSG(extack, "Number of buckets needs to be non-0"); return -EINVAL; } } err = rtm_nh_get_timer(tb[NHA_RES_GROUP_IDLE_TIMER], NH_RES_DEFAULT_IDLE_TIMER, &cfg->nh_grp_res_idle_timer, &cfg->nh_grp_res_has_idle_timer, extack); if (err) return err; return rtm_nh_get_timer(tb[NHA_RES_GROUP_UNBALANCED_TIMER], NH_RES_DEFAULT_UNBALANCED_TIMER, &cfg->nh_grp_res_unbalanced_timer, &cfg->nh_grp_res_has_unbalanced_timer, extack); } static int rtm_to_nh_config(struct net *net, struct sk_buff *skb, struct nlmsghdr *nlh, struct nh_config *cfg, struct netlink_ext_ack *extack) { struct nhmsg *nhm = nlmsg_data(nlh); struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_new)]; int err; err = nlmsg_parse(nlh, sizeof(*nhm), tb, ARRAY_SIZE(rtm_nh_policy_new) - 1, rtm_nh_policy_new, extack); if (err < 0) return err; err = -EINVAL; if (nhm->resvd || nhm->nh_scope) { NL_SET_ERR_MSG(extack, "Invalid values in ancillary header"); goto out; } if (nhm->nh_flags & ~NEXTHOP_VALID_USER_FLAGS) { NL_SET_ERR_MSG(extack, "Invalid nexthop flags in ancillary header"); goto out; } switch (nhm->nh_family) { case AF_INET: case AF_INET6: break; case AF_UNSPEC: if (tb[NHA_GROUP]) break; fallthrough; default: NL_SET_ERR_MSG(extack, "Invalid address family"); goto out; } memset(cfg, 0, sizeof(*cfg)); cfg->nlflags = nlh->nlmsg_flags; cfg->nlinfo.portid = NETLINK_CB(skb).portid; cfg->nlinfo.nlh = nlh; cfg->nlinfo.nl_net = net; cfg->nh_family = nhm->nh_family; cfg->nh_protocol = nhm->nh_protocol; cfg->nh_flags = nhm->nh_flags; if (tb[NHA_ID]) cfg->nh_id = nla_get_u32(tb[NHA_ID]); if (tb[NHA_FDB]) { if (tb[NHA_OIF] || tb[NHA_BLACKHOLE] || tb[NHA_ENCAP] || tb[NHA_ENCAP_TYPE]) { NL_SET_ERR_MSG(extack, "Fdb attribute can not be used with encap, oif or blackhole"); goto out; } if (nhm->nh_flags) { NL_SET_ERR_MSG(extack, "Unsupported nexthop flags in ancillary header"); goto out; } cfg->nh_fdb = nla_get_flag(tb[NHA_FDB]); } if (tb[NHA_GROUP]) { if (nhm->nh_family != AF_UNSPEC) { NL_SET_ERR_MSG(extack, "Invalid family for group"); goto out; } cfg->nh_grp = tb[NHA_GROUP]; cfg->nh_grp_type = NEXTHOP_GRP_TYPE_MPATH; if (tb[NHA_GROUP_TYPE]) cfg->nh_grp_type = nla_get_u16(tb[NHA_GROUP_TYPE]); if (cfg->nh_grp_type > NEXTHOP_GRP_TYPE_MAX) { NL_SET_ERR_MSG(extack, "Invalid group type"); goto out; } err = nh_check_attr_group(net, tb, ARRAY_SIZE(tb), cfg->nh_grp_type, extack); if (err) goto out; if (cfg->nh_grp_type == NEXTHOP_GRP_TYPE_RES) err = rtm_to_nh_config_grp_res(tb[NHA_RES_GROUP], cfg, extack); if (tb[NHA_HW_STATS_ENABLE]) cfg->nh_hw_stats = nla_get_u32(tb[NHA_HW_STATS_ENABLE]); /* no other attributes should be set */ goto out; } if (tb[NHA_BLACKHOLE]) { if (tb[NHA_GATEWAY] || tb[NHA_OIF] || tb[NHA_ENCAP] || tb[NHA_ENCAP_TYPE] || tb[NHA_FDB]) { NL_SET_ERR_MSG(extack, "Blackhole attribute can not be used with gateway, oif, encap or fdb"); goto out; } cfg->nh_blackhole = 1; err = 0; goto out; } if (!cfg->nh_fdb && !tb[NHA_OIF]) { NL_SET_ERR_MSG(extack, "Device attribute required for non-blackhole and non-fdb nexthops"); goto out; } if (!cfg->nh_fdb && tb[NHA_OIF]) { cfg->nh_ifindex = nla_get_u32(tb[NHA_OIF]); if (cfg->nh_ifindex) cfg->dev = __dev_get_by_index(net, cfg->nh_ifindex); if (!cfg->dev) { NL_SET_ERR_MSG(extack, "Invalid device index"); goto out; } else if (!(cfg->dev->flags & IFF_UP)) { NL_SET_ERR_MSG(extack, "Nexthop device is not up"); err = -ENETDOWN; goto out; } else if (!netif_carrier_ok(cfg->dev)) { NL_SET_ERR_MSG(extack, "Carrier for nexthop device is down"); err = -ENETDOWN; goto out; } } err = -EINVAL; if (tb[NHA_GATEWAY]) { struct nlattr *gwa = tb[NHA_GATEWAY]; switch (cfg->nh_family) { case AF_INET: if (nla_len(gwa) != sizeof(u32)) { NL_SET_ERR_MSG(extack, "Invalid gateway"); goto out; } cfg->gw.ipv4 = nla_get_be32(gwa); break; case AF_INET6: if (nla_len(gwa) != sizeof(struct in6_addr)) { NL_SET_ERR_MSG(extack, "Invalid gateway"); goto out; } cfg->gw.ipv6 = nla_get_in6_addr(gwa); break; default: NL_SET_ERR_MSG(extack, "Unknown address family for gateway"); goto out; } } else { /* device only nexthop (no gateway) */ if (cfg->nh_flags & RTNH_F_ONLINK) { NL_SET_ERR_MSG(extack, "ONLINK flag can not be set for nexthop without a gateway"); goto out; } } if (tb[NHA_ENCAP]) { cfg->nh_encap = tb[NHA_ENCAP]; if (!tb[NHA_ENCAP_TYPE]) { NL_SET_ERR_MSG(extack, "LWT encapsulation type is missing"); goto out; } cfg->nh_encap_type = nla_get_u16(tb[NHA_ENCAP_TYPE]); err = lwtunnel_valid_encap_type(cfg->nh_encap_type, extack); if (err < 0) goto out; } else if (tb[NHA_ENCAP_TYPE]) { NL_SET_ERR_MSG(extack, "LWT encapsulation attribute is missing"); goto out; } if (tb[NHA_HW_STATS_ENABLE]) { NL_SET_ERR_MSG(extack, "Cannot enable nexthop hardware statistics for non-group nexthops"); goto out; } err = 0; out: return err; } /* rtnl */ static int rtm_new_nexthop(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct nh_config cfg; struct nexthop *nh; int err; err = rtm_to_nh_config(net, skb, nlh, &cfg, extack); if (!err) { nh = nexthop_add(net, &cfg, extack); if (IS_ERR(nh)) err = PTR_ERR(nh); } return err; } static int nh_valid_get_del_req(const struct nlmsghdr *nlh, struct nlattr **tb, u32 *id, u32 *op_flags, struct netlink_ext_ack *extack) { struct nhmsg *nhm = nlmsg_data(nlh); if (nhm->nh_protocol || nhm->resvd || nhm->nh_scope || nhm->nh_flags) { NL_SET_ERR_MSG(extack, "Invalid values in header"); return -EINVAL; } if (!tb[NHA_ID]) { NL_SET_ERR_MSG(extack, "Nexthop id is missing"); return -EINVAL; } *id = nla_get_u32(tb[NHA_ID]); if (!(*id)) { NL_SET_ERR_MSG(extack, "Invalid nexthop id"); return -EINVAL; } if (op_flags) { if (tb[NHA_OP_FLAGS]) *op_flags = nla_get_u32(tb[NHA_OP_FLAGS]); else *op_flags = 0; } return 0; } /* rtnl */ static int rtm_del_nexthop(struct sk_buff *skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_del)]; struct net *net = sock_net(skb->sk); struct nl_info nlinfo = { .nlh = nlh, .nl_net = net, .portid = NETLINK_CB(skb).portid, }; struct nexthop *nh; int err; u32 id; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_del) - 1, rtm_nh_policy_del, extack); if (err < 0) return err; err = nh_valid_get_del_req(nlh, tb, &id, NULL, extack); if (err) return err; nh = nexthop_find_by_id(net, id); if (!nh) return -ENOENT; remove_nexthop(net, nh, &nlinfo); return 0; } /* rtnl */ static int rtm_get_nexthop(struct sk_buff *in_skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_get)]; struct net *net = sock_net(in_skb->sk); struct sk_buff *skb = NULL; struct nexthop *nh; u32 op_flags; int err; u32 id; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_get) - 1, rtm_nh_policy_get, extack); if (err < 0) return err; err = nh_valid_get_del_req(nlh, tb, &id, &op_flags, extack); if (err) return err; err = -ENOBUFS; skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) goto out; err = -ENOENT; nh = nexthop_find_by_id(net, id); if (!nh) goto errout_free; err = nh_fill_node(skb, nh, RTM_NEWNEXTHOP, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, 0, op_flags); if (err < 0) { WARN_ON(err == -EMSGSIZE); goto errout_free; } err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); out: return err; errout_free: kfree_skb(skb); goto out; } struct nh_dump_filter { u32 nh_id; int dev_idx; int master_idx; bool group_filter; bool fdb_filter; u32 res_bucket_nh_id; u32 op_flags; }; static bool nh_dump_filtered(struct nexthop *nh, struct nh_dump_filter *filter, u8 family) { const struct net_device *dev; const struct nh_info *nhi; if (filter->group_filter && !nh->is_group) return true; if (!filter->dev_idx && !filter->master_idx && !family) return false; if (nh->is_group) return true; nhi = rtnl_dereference(nh->nh_info); if (family && nhi->family != family) return true; dev = nhi->fib_nhc.nhc_dev; if (filter->dev_idx && (!dev || dev->ifindex != filter->dev_idx)) return true; if (filter->master_idx) { struct net_device *master; if (!dev) return true; master = netdev_master_upper_dev_get((struct net_device *)dev); if (!master || master->ifindex != filter->master_idx) return true; } return false; } static int __nh_valid_dump_req(const struct nlmsghdr *nlh, struct nlattr **tb, struct nh_dump_filter *filter, struct netlink_ext_ack *extack) { struct nhmsg *nhm; u32 idx; if (tb[NHA_OIF]) { idx = nla_get_u32(tb[NHA_OIF]); if (idx > INT_MAX) { NL_SET_ERR_MSG(extack, "Invalid device index"); return -EINVAL; } filter->dev_idx = idx; } if (tb[NHA_MASTER]) { idx = nla_get_u32(tb[NHA_MASTER]); if (idx > INT_MAX) { NL_SET_ERR_MSG(extack, "Invalid master device index"); return -EINVAL; } filter->master_idx = idx; } filter->group_filter = nla_get_flag(tb[NHA_GROUPS]); filter->fdb_filter = nla_get_flag(tb[NHA_FDB]); nhm = nlmsg_data(nlh); if (nhm->nh_protocol || nhm->resvd || nhm->nh_scope || nhm->nh_flags) { NL_SET_ERR_MSG(extack, "Invalid values in header for nexthop dump request"); return -EINVAL; } return 0; } static int nh_valid_dump_req(const struct nlmsghdr *nlh, struct nh_dump_filter *filter, struct netlink_callback *cb) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_dump)]; int err; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_dump) - 1, rtm_nh_policy_dump, cb->extack); if (err < 0) return err; if (tb[NHA_OP_FLAGS]) filter->op_flags = nla_get_u32(tb[NHA_OP_FLAGS]); else filter->op_flags = 0; return __nh_valid_dump_req(nlh, tb, filter, cb->extack); } struct rtm_dump_nh_ctx { u32 idx; }; static struct rtm_dump_nh_ctx * rtm_dump_nh_ctx(struct netlink_callback *cb) { struct rtm_dump_nh_ctx *ctx = (void *)cb->ctx; BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx)); return ctx; } static int rtm_dump_walk_nexthops(struct sk_buff *skb, struct netlink_callback *cb, struct rb_root *root, struct rtm_dump_nh_ctx *ctx, int (*nh_cb)(struct sk_buff *skb, struct netlink_callback *cb, struct nexthop *nh, void *data), void *data) { struct rb_node *node; int s_idx; int err; s_idx = ctx->idx; for (node = rb_first(root); node; node = rb_next(node)) { struct nexthop *nh; nh = rb_entry(node, struct nexthop, rb_node); if (nh->id < s_idx) continue; ctx->idx = nh->id; err = nh_cb(skb, cb, nh, data); if (err) return err; } return 0; } static int rtm_dump_nexthop_cb(struct sk_buff *skb, struct netlink_callback *cb, struct nexthop *nh, void *data) { struct nhmsg *nhm = nlmsg_data(cb->nlh); struct nh_dump_filter *filter = data; if (nh_dump_filtered(nh, filter, nhm->nh_family)) return 0; return nh_fill_node(skb, nh, RTM_NEWNEXTHOP, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, filter->op_flags); } /* rtnl */ static int rtm_dump_nexthop(struct sk_buff *skb, struct netlink_callback *cb) { struct rtm_dump_nh_ctx *ctx = rtm_dump_nh_ctx(cb); struct net *net = sock_net(skb->sk); struct rb_root *root = &net->nexthop.rb_root; struct nh_dump_filter filter = {}; int err; err = nh_valid_dump_req(cb->nlh, &filter, cb); if (err < 0) return err; err = rtm_dump_walk_nexthops(skb, cb, root, ctx, &rtm_dump_nexthop_cb, &filter); cb->seq = net->nexthop.seq; nl_dump_check_consistent(cb, nlmsg_hdr(skb)); return err; } static struct nexthop * nexthop_find_group_resilient(struct net *net, u32 id, struct netlink_ext_ack *extack) { struct nh_group *nhg; struct nexthop *nh; nh = nexthop_find_by_id(net, id); if (!nh) return ERR_PTR(-ENOENT); if (!nh->is_group) { NL_SET_ERR_MSG(extack, "Not a nexthop group"); return ERR_PTR(-EINVAL); } nhg = rtnl_dereference(nh->nh_grp); if (!nhg->resilient) { NL_SET_ERR_MSG(extack, "Nexthop group not of type resilient"); return ERR_PTR(-EINVAL); } return nh; } static int nh_valid_dump_nhid(struct nlattr *attr, u32 *nh_id_p, struct netlink_ext_ack *extack) { u32 idx; if (attr) { idx = nla_get_u32(attr); if (!idx) { NL_SET_ERR_MSG(extack, "Invalid nexthop id"); return -EINVAL; } *nh_id_p = idx; } else { *nh_id_p = 0; } return 0; } static int nh_valid_dump_bucket_req(const struct nlmsghdr *nlh, struct nh_dump_filter *filter, struct netlink_callback *cb) { struct nlattr *res_tb[ARRAY_SIZE(rtm_nh_res_bucket_policy_dump)]; struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_dump_bucket)]; int err; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_dump_bucket) - 1, rtm_nh_policy_dump_bucket, NULL); if (err < 0) return err; err = nh_valid_dump_nhid(tb[NHA_ID], &filter->nh_id, cb->extack); if (err) return err; if (tb[NHA_RES_BUCKET]) { size_t max = ARRAY_SIZE(rtm_nh_res_bucket_policy_dump) - 1; err = nla_parse_nested(res_tb, max, tb[NHA_RES_BUCKET], rtm_nh_res_bucket_policy_dump, cb->extack); if (err < 0) return err; err = nh_valid_dump_nhid(res_tb[NHA_RES_BUCKET_NH_ID], &filter->res_bucket_nh_id, cb->extack); if (err) return err; } return __nh_valid_dump_req(nlh, tb, filter, cb->extack); } struct rtm_dump_res_bucket_ctx { struct rtm_dump_nh_ctx nh; u16 bucket_index; }; static struct rtm_dump_res_bucket_ctx * rtm_dump_res_bucket_ctx(struct netlink_callback *cb) { struct rtm_dump_res_bucket_ctx *ctx = (void *)cb->ctx; BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx)); return ctx; } struct rtm_dump_nexthop_bucket_data { struct rtm_dump_res_bucket_ctx *ctx; struct nh_dump_filter filter; }; static int rtm_dump_nexthop_bucket_nh(struct sk_buff *skb, struct netlink_callback *cb, struct nexthop *nh, struct rtm_dump_nexthop_bucket_data *dd) { u32 portid = NETLINK_CB(cb->skb).portid; struct nhmsg *nhm = nlmsg_data(cb->nlh); struct nh_res_table *res_table; struct nh_group *nhg; u16 bucket_index; int err; nhg = rtnl_dereference(nh->nh_grp); res_table = rtnl_dereference(nhg->res_table); for (bucket_index = dd->ctx->bucket_index; bucket_index < res_table->num_nh_buckets; bucket_index++) { struct nh_res_bucket *bucket; struct nh_grp_entry *nhge; bucket = &res_table->nh_buckets[bucket_index]; nhge = rtnl_dereference(bucket->nh_entry); if (nh_dump_filtered(nhge->nh, &dd->filter, nhm->nh_family)) continue; if (dd->filter.res_bucket_nh_id && dd->filter.res_bucket_nh_id != nhge->nh->id) continue; dd->ctx->bucket_index = bucket_index; err = nh_fill_res_bucket(skb, nh, bucket, bucket_index, RTM_NEWNEXTHOPBUCKET, portid, cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->extack); if (err) return err; } dd->ctx->bucket_index = 0; return 0; } static int rtm_dump_nexthop_bucket_cb(struct sk_buff *skb, struct netlink_callback *cb, struct nexthop *nh, void *data) { struct rtm_dump_nexthop_bucket_data *dd = data; struct nh_group *nhg; if (!nh->is_group) return 0; nhg = rtnl_dereference(nh->nh_grp); if (!nhg->resilient) return 0; return rtm_dump_nexthop_bucket_nh(skb, cb, nh, dd); } /* rtnl */ static int rtm_dump_nexthop_bucket(struct sk_buff *skb, struct netlink_callback *cb) { struct rtm_dump_res_bucket_ctx *ctx = rtm_dump_res_bucket_ctx(cb); struct rtm_dump_nexthop_bucket_data dd = { .ctx = ctx }; struct net *net = sock_net(skb->sk); struct nexthop *nh; int err; err = nh_valid_dump_bucket_req(cb->nlh, &dd.filter, cb); if (err) return err; if (dd.filter.nh_id) { nh = nexthop_find_group_resilient(net, dd.filter.nh_id, cb->extack); if (IS_ERR(nh)) return PTR_ERR(nh); err = rtm_dump_nexthop_bucket_nh(skb, cb, nh, &dd); } else { struct rb_root *root = &net->nexthop.rb_root; err = rtm_dump_walk_nexthops(skb, cb, root, &ctx->nh, &rtm_dump_nexthop_bucket_cb, &dd); } cb->seq = net->nexthop.seq; nl_dump_check_consistent(cb, nlmsg_hdr(skb)); return err; } static int nh_valid_get_bucket_req_res_bucket(struct nlattr *res, u16 *bucket_index, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_res_bucket_policy_get)]; int err; err = nla_parse_nested(tb, ARRAY_SIZE(rtm_nh_res_bucket_policy_get) - 1, res, rtm_nh_res_bucket_policy_get, extack); if (err < 0) return err; if (!tb[NHA_RES_BUCKET_INDEX]) { NL_SET_ERR_MSG(extack, "Bucket index is missing"); return -EINVAL; } *bucket_index = nla_get_u16(tb[NHA_RES_BUCKET_INDEX]); return 0; } static int nh_valid_get_bucket_req(const struct nlmsghdr *nlh, u32 *id, u16 *bucket_index, struct netlink_ext_ack *extack) { struct nlattr *tb[ARRAY_SIZE(rtm_nh_policy_get_bucket)]; int err; err = nlmsg_parse(nlh, sizeof(struct nhmsg), tb, ARRAY_SIZE(rtm_nh_policy_get_bucket) - 1, rtm_nh_policy_get_bucket, extack); if (err < 0) return err; err = nh_valid_get_del_req(nlh, tb, id, NULL, extack); if (err) return err; if (!tb[NHA_RES_BUCKET]) { NL_SET_ERR_MSG(extack, "Bucket information is missing"); return -EINVAL; } err = nh_valid_get_bucket_req_res_bucket(tb[NHA_RES_BUCKET], bucket_index, extack); if (err) return err; return 0; } /* rtnl */ static int rtm_get_nexthop_bucket(struct sk_buff *in_skb, struct nlmsghdr *nlh, struct netlink_ext_ack *extack) { struct net *net = sock_net(in_skb->sk); struct nh_res_table *res_table; struct sk_buff *skb = NULL; struct nh_group *nhg; struct nexthop *nh; u16 bucket_index; int err; u32 id; err = nh_valid_get_bucket_req(nlh, &id, &bucket_index, extack); if (err) return err; nh = nexthop_find_group_resilient(net, id, extack); if (IS_ERR(nh)) return PTR_ERR(nh); nhg = rtnl_dereference(nh->nh_grp); res_table = rtnl_dereference(nhg->res_table); if (bucket_index >= res_table->num_nh_buckets) { NL_SET_ERR_MSG(extack, "Bucket index out of bounds"); return -ENOENT; } skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return -ENOBUFS; err = nh_fill_res_bucket(skb, nh, &res_table->nh_buckets[bucket_index], bucket_index, RTM_NEWNEXTHOPBUCKET, NETLINK_CB(in_skb).portid, nlh->nlmsg_seq, 0, extack); if (err < 0) { WARN_ON(err == -EMSGSIZE); goto errout_free; } return rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid); errout_free: kfree_skb(skb); return err; } static void nexthop_sync_mtu(struct net_device *dev, u32 orig_mtu) { unsigned int hash = nh_dev_hashfn(dev->ifindex); struct net *net = dev_net(dev); struct hlist_head *head = &net->nexthop.devhash[hash]; struct hlist_node *n; struct nh_info *nhi; hlist_for_each_entry_safe(nhi, n, head, dev_hash) { if (nhi->fib_nhc.nhc_dev == dev) { if (nhi->family == AF_INET) fib_nhc_update_mtu(&nhi->fib_nhc, dev->mtu, orig_mtu); } } } /* rtnl */ static int nh_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) { struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct netdev_notifier_info_ext *info_ext; switch (event) { case NETDEV_DOWN: case NETDEV_UNREGISTER: nexthop_flush_dev(dev, event); break; case NETDEV_CHANGE: if (!(dev_get_flags(dev) & (IFF_RUNNING | IFF_LOWER_UP))) nexthop_flush_dev(dev, event); break; case NETDEV_CHANGEMTU: info_ext = ptr; nexthop_sync_mtu(dev, info_ext->ext.mtu); rt_cache_flush(dev_net(dev)); break; } return NOTIFY_DONE; } static struct notifier_block nh_netdev_notifier = { .notifier_call = nh_netdev_event, }; static int nexthops_dump(struct net *net, struct notifier_block *nb, enum nexthop_event_type event_type, struct netlink_ext_ack *extack) { struct rb_root *root = &net->nexthop.rb_root; struct rb_node *node; int err = 0; for (node = rb_first(root); node; node = rb_next(node)) { struct nexthop *nh; nh = rb_entry(node, struct nexthop, rb_node); err = call_nexthop_notifier(nb, net, event_type, nh, extack); if (err) break; } return err; } int register_nexthop_notifier(struct net *net, struct notifier_block *nb, struct netlink_ext_ack *extack) { int err; rtnl_lock(); err = nexthops_dump(net, nb, NEXTHOP_EVENT_REPLACE, extack); if (err) goto unlock; err = blocking_notifier_chain_register(&net->nexthop.notifier_chain, nb); unlock: rtnl_unlock(); return err; } EXPORT_SYMBOL(register_nexthop_notifier); int __unregister_nexthop_notifier(struct net *net, struct notifier_block *nb) { int err; err = blocking_notifier_chain_unregister(&net->nexthop.notifier_chain, nb); if (!err) nexthops_dump(net, nb, NEXTHOP_EVENT_DEL, NULL); return err; } EXPORT_SYMBOL(__unregister_nexthop_notifier); int unregister_nexthop_notifier(struct net *net, struct notifier_block *nb) { int err; rtnl_lock(); err = __unregister_nexthop_notifier(net, nb); rtnl_unlock(); return err; } EXPORT_SYMBOL(unregister_nexthop_notifier); void nexthop_set_hw_flags(struct net *net, u32 id, bool offload, bool trap) { struct nexthop *nexthop; rcu_read_lock(); nexthop = nexthop_find_by_id(net, id); if (!nexthop) goto out; nexthop->nh_flags &= ~(RTNH_F_OFFLOAD | RTNH_F_TRAP); if (offload) nexthop->nh_flags |= RTNH_F_OFFLOAD; if (trap) nexthop->nh_flags |= RTNH_F_TRAP; out: rcu_read_unlock(); } EXPORT_SYMBOL(nexthop_set_hw_flags); void nexthop_bucket_set_hw_flags(struct net *net, u32 id, u16 bucket_index, bool offload, bool trap) { struct nh_res_table *res_table; struct nh_res_bucket *bucket; struct nexthop *nexthop; struct nh_group *nhg; rcu_read_lock(); nexthop = nexthop_find_by_id(net, id); if (!nexthop || !nexthop->is_group) goto out; nhg = rcu_dereference(nexthop->nh_grp); if (!nhg->resilient) goto out; if (bucket_index >= nhg->res_table->num_nh_buckets) goto out; res_table = rcu_dereference(nhg->res_table); bucket = &res_table->nh_buckets[bucket_index]; bucket->nh_flags &= ~(RTNH_F_OFFLOAD | RTNH_F_TRAP); if (offload) bucket->nh_flags |= RTNH_F_OFFLOAD; if (trap) bucket->nh_flags |= RTNH_F_TRAP; out: rcu_read_unlock(); } EXPORT_SYMBOL(nexthop_bucket_set_hw_flags); void nexthop_res_grp_activity_update(struct net *net, u32 id, u16 num_buckets, unsigned long *activity) { struct nh_res_table *res_table; struct nexthop *nexthop; struct nh_group *nhg; u16 i; rcu_read_lock(); nexthop = nexthop_find_by_id(net, id); if (!nexthop || !nexthop->is_group) goto out; nhg = rcu_dereference(nexthop->nh_grp); if (!nhg->resilient) goto out; /* Instead of silently ignoring some buckets, demand that the sizes * be the same. */ res_table = rcu_dereference(nhg->res_table); if (num_buckets != res_table->num_nh_buckets) goto out; for (i = 0; i < num_buckets; i++) { if (test_bit(i, activity)) nh_res_bucket_set_busy(&res_table->nh_buckets[i]); } out: rcu_read_unlock(); } EXPORT_SYMBOL(nexthop_res_grp_activity_update); static void __net_exit nexthop_net_exit_batch_rtnl(struct list_head *net_list, struct list_head *dev_to_kill) { struct net *net; ASSERT_RTNL(); list_for_each_entry(net, net_list, exit_list) flush_all_nexthops(net); } static void __net_exit nexthop_net_exit(struct net *net) { kfree(net->nexthop.devhash); net->nexthop.devhash = NULL; } static int __net_init nexthop_net_init(struct net *net) { size_t sz = sizeof(struct hlist_head) * NH_DEV_HASHSIZE; net->nexthop.rb_root = RB_ROOT; net->nexthop.devhash = kzalloc(sz, GFP_KERNEL); if (!net->nexthop.devhash) return -ENOMEM; BLOCKING_INIT_NOTIFIER_HEAD(&net->nexthop.notifier_chain); return 0; } static struct pernet_operations nexthop_net_ops = { .init = nexthop_net_init, .exit = nexthop_net_exit, .exit_batch_rtnl = nexthop_net_exit_batch_rtnl, }; static int __init nexthop_init(void) { register_pernet_subsys(&nexthop_net_ops); register_netdevice_notifier(&nh_netdev_notifier); rtnl_register(PF_UNSPEC, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0); rtnl_register(PF_UNSPEC, RTM_DELNEXTHOP, rtm_del_nexthop, NULL, 0); rtnl_register(PF_UNSPEC, RTM_GETNEXTHOP, rtm_get_nexthop, rtm_dump_nexthop, 0); rtnl_register(PF_INET, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0); rtnl_register(PF_INET, RTM_GETNEXTHOP, NULL, rtm_dump_nexthop, 0); rtnl_register(PF_INET6, RTM_NEWNEXTHOP, rtm_new_nexthop, NULL, 0); rtnl_register(PF_INET6, RTM_GETNEXTHOP, NULL, rtm_dump_nexthop, 0); rtnl_register(PF_UNSPEC, RTM_GETNEXTHOPBUCKET, rtm_get_nexthop_bucket, rtm_dump_nexthop_bucket, 0); return 0; } subsys_initcall(nexthop_init);