// SPDX-License-Identifier: GPL-2.0-or-later /* * net/sched/act_api.c Packet action API. * * Author: Jamal Hadi Salim */ #include <linux/types.h> #include <linux/kernel.h> #include <linux/string.h> #include <linux/errno.h> #include <linux/slab.h> #include <linux/skbuff.h> #include <linux/init.h> #include <linux/kmod.h> #include <linux/err.h> #include <linux/module.h> #include <net/net_namespace.h> #include <net/sock.h> #include <net/sch_generic.h> #include <net/pkt_cls.h> #include <net/act_api.h> #include <net/netlink.h> static void tcf_action_goto_chain_exec(const struct tc_action *a, struct tcf_result *res) { const struct tcf_chain *chain = rcu_dereference_bh(a->goto_chain); res->goto_tp = rcu_dereference_bh(chain->filter_chain); } static void tcf_free_cookie_rcu(struct rcu_head *p) { struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu); kfree(cookie->data); kfree(cookie); } static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie, struct tc_cookie *new_cookie) { struct tc_cookie *old; old = xchg((__force struct tc_cookie **)old_cookie, new_cookie); if (old) call_rcu(&old->rcu, tcf_free_cookie_rcu); } int tcf_action_check_ctrlact(int action, struct tcf_proto *tp, struct tcf_chain **newchain, struct netlink_ext_ack *extack) { int opcode = TC_ACT_EXT_OPCODE(action), ret = -EINVAL; u32 chain_index; if (!opcode) ret = action > TC_ACT_VALUE_MAX ? -EINVAL : 0; else if (opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC) ret = 0; if (ret) { NL_SET_ERR_MSG(extack, "invalid control action"); goto end; } if (TC_ACT_EXT_CMP(action, TC_ACT_GOTO_CHAIN)) { chain_index = action & TC_ACT_EXT_VAL_MASK; if (!tp || !newchain) { ret = -EINVAL; NL_SET_ERR_MSG(extack, "can't goto NULL proto/chain"); goto end; } *newchain = tcf_chain_get_by_act(tp->chain->block, chain_index); if (!*newchain) { ret = -ENOMEM; NL_SET_ERR_MSG(extack, "can't allocate goto_chain"); } } end: return ret; } EXPORT_SYMBOL(tcf_action_check_ctrlact); struct tcf_chain *tcf_action_set_ctrlact(struct tc_action *a, int action, struct tcf_chain *goto_chain) { a->tcfa_action = action; goto_chain = rcu_replace_pointer(a->goto_chain, goto_chain, 1); return goto_chain; } EXPORT_SYMBOL(tcf_action_set_ctrlact); /* XXX: For standalone actions, we don't need a RCU grace period either, because * actions are always connected to filters and filters are already destroyed in * RCU callbacks, so after a RCU grace period actions are already disconnected * from filters. Readers later can not find us. */ static void free_tcf(struct tc_action *p) { struct tcf_chain *chain = rcu_dereference_protected(p->goto_chain, 1); free_percpu(p->cpu_bstats); free_percpu(p->cpu_bstats_hw); free_percpu(p->cpu_qstats); tcf_set_action_cookie(&p->act_cookie, NULL); if (chain) tcf_chain_put_by_act(chain); kfree(p); } static void tcf_action_cleanup(struct tc_action *p) { if (p->ops->cleanup) p->ops->cleanup(p); gen_kill_estimator(&p->tcfa_rate_est); free_tcf(p); } static int __tcf_action_put(struct tc_action *p, bool bind) { struct tcf_idrinfo *idrinfo = p->idrinfo; if (refcount_dec_and_mutex_lock(&p->tcfa_refcnt, &idrinfo->lock)) { if (bind) atomic_dec(&p->tcfa_bindcnt); idr_remove(&idrinfo->action_idr, p->tcfa_index); mutex_unlock(&idrinfo->lock); tcf_action_cleanup(p); return 1; } if (bind) atomic_dec(&p->tcfa_bindcnt); return 0; } int __tcf_idr_release(struct tc_action *p, bool bind, bool strict) { int ret = 0; /* Release with strict==1 and bind==0 is only called through act API * interface (classifiers always bind). Only case when action with * positive reference count and zero bind count can exist is when it was * also created with act API (unbinding last classifier will destroy the * action if it was created by classifier). So only case when bind count * can be changed after initial check is when unbound action is * destroyed by act API while classifier binds to action with same id * concurrently. This result either creation of new action(same behavior * as before), or reusing existing action if concurrent process * increments reference count before action is deleted. Both scenarios * are acceptable. */ if (p) { if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0) return -EPERM; if (__tcf_action_put(p, bind)) ret = ACT_P_DELETED; } return ret; } EXPORT_SYMBOL(__tcf_idr_release); static size_t tcf_action_shared_attrs_size(const struct tc_action *act) { struct tc_cookie *act_cookie; u32 cookie_len = 0; rcu_read_lock(); act_cookie = rcu_dereference(act->act_cookie); if (act_cookie) cookie_len = nla_total_size(act_cookie->len); rcu_read_unlock(); return nla_total_size(0) /* action number nested */ + nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */ + cookie_len /* TCA_ACT_COOKIE */ + nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_HW_STATS */ + nla_total_size(0) /* TCA_ACT_STATS nested */ + nla_total_size(sizeof(struct nla_bitfield32)) /* TCA_ACT_FLAGS */ /* TCA_STATS_BASIC */ + nla_total_size_64bit(sizeof(struct gnet_stats_basic)) /* TCA_STATS_PKT64 */ + nla_total_size_64bit(sizeof(u64)) /* TCA_STATS_QUEUE */ + nla_total_size_64bit(sizeof(struct gnet_stats_queue)) + nla_total_size(0) /* TCA_OPTIONS nested */ + nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */ } static size_t tcf_action_full_attrs_size(size_t sz) { return NLMSG_HDRLEN /* struct nlmsghdr */ + sizeof(struct tcamsg) + nla_total_size(0) /* TCA_ACT_TAB nested */ + sz; } static size_t tcf_action_fill_size(const struct tc_action *act) { size_t sz = tcf_action_shared_attrs_size(act); if (act->ops->get_fill_size) return act->ops->get_fill_size(act) + sz; return sz; } static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb, struct netlink_callback *cb) { int err = 0, index = -1, s_i = 0, n_i = 0; u32 act_flags = cb->args[2]; unsigned long jiffy_since = cb->args[3]; struct nlattr *nest; struct idr *idr = &idrinfo->action_idr; struct tc_action *p; unsigned long id = 1; unsigned long tmp; mutex_lock(&idrinfo->lock); s_i = cb->args[0]; idr_for_each_entry_ul(idr, p, tmp, id) { index++; if (index < s_i) continue; if (jiffy_since && time_after(jiffy_since, (unsigned long)p->tcfa_tm.lastuse)) continue; nest = nla_nest_start_noflag(skb, n_i); if (!nest) { index--; goto nla_put_failure; } err = tcf_action_dump_1(skb, p, 0, 0); if (err < 0) { index--; nlmsg_trim(skb, nest); goto done; } nla_nest_end(skb, nest); n_i++; if (!(act_flags & TCA_FLAG_LARGE_DUMP_ON) && n_i >= TCA_ACT_MAX_PRIO) goto done; } done: if (index >= 0) cb->args[0] = index + 1; mutex_unlock(&idrinfo->lock); if (n_i) { if (act_flags & TCA_FLAG_LARGE_DUMP_ON) cb->args[1] = n_i; } return n_i; nla_put_failure: nla_nest_cancel(skb, nest); goto done; } static int tcf_idr_release_unsafe(struct tc_action *p) { if (atomic_read(&p->tcfa_bindcnt) > 0) return -EPERM; if (refcount_dec_and_test(&p->tcfa_refcnt)) { idr_remove(&p->idrinfo->action_idr, p->tcfa_index); tcf_action_cleanup(p); return ACT_P_DELETED; } return 0; } static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb, const struct tc_action_ops *ops) { struct nlattr *nest; int n_i = 0; int ret = -EINVAL; struct idr *idr = &idrinfo->action_idr; struct tc_action *p; unsigned long id = 1; unsigned long tmp; nest = nla_nest_start_noflag(skb, 0); if (nest == NULL) goto nla_put_failure; if (nla_put_string(skb, TCA_KIND, ops->kind)) goto nla_put_failure; mutex_lock(&idrinfo->lock); idr_for_each_entry_ul(idr, p, tmp, id) { ret = tcf_idr_release_unsafe(p); if (ret == ACT_P_DELETED) { module_put(ops->owner); n_i++; } else if (ret < 0) { mutex_unlock(&idrinfo->lock); goto nla_put_failure; } } mutex_unlock(&idrinfo->lock); if (nla_put_u32(skb, TCA_FCNT, n_i)) goto nla_put_failure; nla_nest_end(skb, nest); return n_i; nla_put_failure: nla_nest_cancel(skb, nest); return ret; } int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb, struct netlink_callback *cb, int type, const struct tc_action_ops *ops, struct netlink_ext_ack *extack) { struct tcf_idrinfo *idrinfo = tn->idrinfo; if (type == RTM_DELACTION) { return tcf_del_walker(idrinfo, skb, ops); } else if (type == RTM_GETACTION) { return tcf_dump_walker(idrinfo, skb, cb); } else { WARN(1, "tcf_generic_walker: unknown command %d\n", type); NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command"); return -EINVAL; } } EXPORT_SYMBOL(tcf_generic_walker); int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index) { struct tcf_idrinfo *idrinfo = tn->idrinfo; struct tc_action *p; mutex_lock(&idrinfo->lock); p = idr_find(&idrinfo->action_idr, index); if (IS_ERR(p)) p = NULL; else if (p) refcount_inc(&p->tcfa_refcnt); mutex_unlock(&idrinfo->lock); if (p) { *a = p; return true; } return false; } EXPORT_SYMBOL(tcf_idr_search); static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index) { struct tc_action *p; int ret = 0; mutex_lock(&idrinfo->lock); p = idr_find(&idrinfo->action_idr, index); if (!p) { mutex_unlock(&idrinfo->lock); return -ENOENT; } if (!atomic_read(&p->tcfa_bindcnt)) { if (refcount_dec_and_test(&p->tcfa_refcnt)) { struct module *owner = p->ops->owner; WARN_ON(p != idr_remove(&idrinfo->action_idr, p->tcfa_index)); mutex_unlock(&idrinfo->lock); tcf_action_cleanup(p); module_put(owner); return 0; } ret = 0; } else { ret = -EPERM; } mutex_unlock(&idrinfo->lock); return ret; } int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est, struct tc_action **a, const struct tc_action_ops *ops, int bind, bool cpustats, u32 flags) { struct tc_action *p = kzalloc(ops->size, GFP_KERNEL); struct tcf_idrinfo *idrinfo = tn->idrinfo; int err = -ENOMEM; if (unlikely(!p)) return -ENOMEM; refcount_set(&p->tcfa_refcnt, 1); if (bind) atomic_set(&p->tcfa_bindcnt, 1); if (cpustats) { p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu); if (!p->cpu_bstats) goto err1; p->cpu_bstats_hw = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu); if (!p->cpu_bstats_hw) goto err2; p->cpu_qstats = alloc_percpu(struct gnet_stats_queue); if (!p->cpu_qstats) goto err3; } spin_lock_init(&p->tcfa_lock); p->tcfa_index = index; p->tcfa_tm.install = jiffies; p->tcfa_tm.lastuse = jiffies; p->tcfa_tm.firstuse = 0; p->tcfa_flags = flags; if (est) { err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats, &p->tcfa_rate_est, &p->tcfa_lock, NULL, est); if (err) goto err4; } p->idrinfo = idrinfo; p->ops = ops; *a = p; return 0; err4: free_percpu(p->cpu_qstats); err3: free_percpu(p->cpu_bstats_hw); err2: free_percpu(p->cpu_bstats); err1: kfree(p); return err; } EXPORT_SYMBOL(tcf_idr_create); int tcf_idr_create_from_flags(struct tc_action_net *tn, u32 index, struct nlattr *est, struct tc_action **a, const struct tc_action_ops *ops, int bind, u32 flags) { /* Set cpustats according to actions flags. */ return tcf_idr_create(tn, index, est, a, ops, bind, !(flags & TCA_ACT_FLAGS_NO_PERCPU_STATS), flags); } EXPORT_SYMBOL(tcf_idr_create_from_flags); void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a) { struct tcf_idrinfo *idrinfo = tn->idrinfo; mutex_lock(&idrinfo->lock); /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */ WARN_ON(!IS_ERR(idr_replace(&idrinfo->action_idr, a, a->tcfa_index))); mutex_unlock(&idrinfo->lock); } EXPORT_SYMBOL(tcf_idr_insert); /* Cleanup idr index that was allocated but not initialized. */ void tcf_idr_cleanup(struct tc_action_net *tn, u32 index) { struct tcf_idrinfo *idrinfo = tn->idrinfo; mutex_lock(&idrinfo->lock); /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */ WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index))); mutex_unlock(&idrinfo->lock); } EXPORT_SYMBOL(tcf_idr_cleanup); /* Check if action with specified index exists. If actions is found, increments * its reference and bind counters, and return 1. Otherwise insert temporary * error pointer (to prevent concurrent users from inserting actions with same * index) and return 0. */ int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index, struct tc_action **a, int bind) { struct tcf_idrinfo *idrinfo = tn->idrinfo; struct tc_action *p; int ret; again: mutex_lock(&idrinfo->lock); if (*index) { p = idr_find(&idrinfo->action_idr, *index); if (IS_ERR(p)) { /* This means that another process allocated * index but did not assign the pointer yet. */ mutex_unlock(&idrinfo->lock); goto again; } if (p) { refcount_inc(&p->tcfa_refcnt); if (bind) atomic_inc(&p->tcfa_bindcnt); *a = p; ret = 1; } else { *a = NULL; ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index, *index, GFP_KERNEL); if (!ret) idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY), *index); } } else { *index = 1; *a = NULL; ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index, UINT_MAX, GFP_KERNEL); if (!ret) idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY), *index); } mutex_unlock(&idrinfo->lock); return ret; } EXPORT_SYMBOL(tcf_idr_check_alloc); void tcf_idrinfo_destroy(const struct tc_action_ops *ops, struct tcf_idrinfo *idrinfo) { struct idr *idr = &idrinfo->action_idr; struct tc_action *p; int ret; unsigned long id = 1; unsigned long tmp; idr_for_each_entry_ul(idr, p, tmp, id) { ret = __tcf_idr_release(p, false, true); if (ret == ACT_P_DELETED) module_put(ops->owner); else if (ret < 0) return; } idr_destroy(&idrinfo->action_idr); } EXPORT_SYMBOL(tcf_idrinfo_destroy); static LIST_HEAD(act_base); static DEFINE_RWLOCK(act_mod_lock); int tcf_register_action(struct tc_action_ops *act, struct pernet_operations *ops) { struct tc_action_ops *a; int ret; if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup) return -EINVAL; /* We have to register pernet ops before making the action ops visible, * otherwise tcf_action_init_1() could get a partially initialized * netns. */ ret = register_pernet_subsys(ops); if (ret) return ret; write_lock(&act_mod_lock); list_for_each_entry(a, &act_base, head) { if (act->id == a->id || (strcmp(act->kind, a->kind) == 0)) { write_unlock(&act_mod_lock); unregister_pernet_subsys(ops); return -EEXIST; } } list_add_tail(&act->head, &act_base); write_unlock(&act_mod_lock); return 0; } EXPORT_SYMBOL(tcf_register_action); int tcf_unregister_action(struct tc_action_ops *act, struct pernet_operations *ops) { struct tc_action_ops *a; int err = -ENOENT; write_lock(&act_mod_lock); list_for_each_entry(a, &act_base, head) { if (a == act) { list_del(&act->head); err = 0; break; } } write_unlock(&act_mod_lock); if (!err) unregister_pernet_subsys(ops); return err; } EXPORT_SYMBOL(tcf_unregister_action); /* lookup by name */ static struct tc_action_ops *tc_lookup_action_n(char *kind) { struct tc_action_ops *a, *res = NULL; if (kind) { read_lock(&act_mod_lock); list_for_each_entry(a, &act_base, head) { if (strcmp(kind, a->kind) == 0) { if (try_module_get(a->owner)) res = a; break; } } read_unlock(&act_mod_lock); } return res; } /* lookup by nlattr */ static struct tc_action_ops *tc_lookup_action(struct nlattr *kind) { struct tc_action_ops *a, *res = NULL; if (kind) { read_lock(&act_mod_lock); list_for_each_entry(a, &act_base, head) { if (nla_strcmp(kind, a->kind) == 0) { if (try_module_get(a->owner)) res = a; break; } } read_unlock(&act_mod_lock); } return res; } /*TCA_ACT_MAX_PRIO is 32, there count upto 32 */ #define TCA_ACT_MAX_PRIO_MASK 0x1FF int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions, int nr_actions, struct tcf_result *res) { u32 jmp_prgcnt = 0; u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */ int i; int ret = TC_ACT_OK; if (skb_skip_tc_classify(skb)) return TC_ACT_OK; restart_act_graph: for (i = 0; i < nr_actions; i++) { const struct tc_action *a = actions[i]; if (jmp_prgcnt > 0) { jmp_prgcnt -= 1; continue; } repeat: ret = a->ops->act(skb, a, res); if (ret == TC_ACT_REPEAT) goto repeat; /* we need a ttl - JHS */ if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) { jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK; if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) { /* faulty opcode, stop pipeline */ return TC_ACT_OK; } else { jmp_ttl -= 1; if (jmp_ttl > 0) goto restart_act_graph; else /* faulty graph, stop pipeline */ return TC_ACT_OK; } } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) { if (unlikely(!rcu_access_pointer(a->goto_chain))) { net_warn_ratelimited("can't go to NULL chain!\n"); return TC_ACT_SHOT; } tcf_action_goto_chain_exec(a, res); } if (ret != TC_ACT_PIPE) break; } return ret; } EXPORT_SYMBOL(tcf_action_exec); int tcf_action_destroy(struct tc_action *actions[], int bind) { const struct tc_action_ops *ops; struct tc_action *a; int ret = 0, i; for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) { a = actions[i]; actions[i] = NULL; ops = a->ops; ret = __tcf_idr_release(a, bind, true); if (ret == ACT_P_DELETED) module_put(ops->owner); else if (ret < 0) return ret; } return ret; } static int tcf_action_destroy_1(struct tc_action *a, int bind) { struct tc_action *actions[] = { a, NULL }; return tcf_action_destroy(actions, bind); } static int tcf_action_put(struct tc_action *p) { return __tcf_action_put(p, false); } /* Put all actions in this array, skip those NULL's. */ static void tcf_action_put_many(struct tc_action *actions[]) { int i; for (i = 0; i < TCA_ACT_MAX_PRIO; i++) { struct tc_action *a = actions[i]; const struct tc_action_ops *ops; if (!a) continue; ops = a->ops; if (tcf_action_put(a)) module_put(ops->owner); } } int tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref) { return a->ops->dump(skb, a, bind, ref); } int tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref) { int err = -EINVAL; unsigned char *b = skb_tail_pointer(skb); struct nlattr *nest; struct tc_cookie *cookie; if (nla_put_string(skb, TCA_KIND, a->ops->kind)) goto nla_put_failure; if (tcf_action_copy_stats(skb, a, 0)) goto nla_put_failure; rcu_read_lock(); cookie = rcu_dereference(a->act_cookie); if (cookie) { if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) { rcu_read_unlock(); goto nla_put_failure; } } rcu_read_unlock(); if (a->hw_stats != TCA_ACT_HW_STATS_ANY && nla_put_bitfield32(skb, TCA_ACT_HW_STATS, a->hw_stats, TCA_ACT_HW_STATS_ANY)) goto nla_put_failure; if (a->used_hw_stats_valid && nla_put_bitfield32(skb, TCA_ACT_USED_HW_STATS, a->used_hw_stats, TCA_ACT_HW_STATS_ANY)) goto nla_put_failure; if (a->tcfa_flags && nla_put_bitfield32(skb, TCA_ACT_FLAGS, a->tcfa_flags, a->tcfa_flags)) goto nla_put_failure; nest = nla_nest_start_noflag(skb, TCA_OPTIONS); if (nest == NULL) goto nla_put_failure; err = tcf_action_dump_old(skb, a, bind, ref); if (err > 0) { nla_nest_end(skb, nest); return err; } nla_put_failure: nlmsg_trim(skb, b); return -1; } EXPORT_SYMBOL(tcf_action_dump_1); int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[], int bind, int ref) { struct tc_action *a; int err = -EINVAL, i; struct nlattr *nest; for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) { a = actions[i]; nest = nla_nest_start_noflag(skb, i + 1); if (nest == NULL) goto nla_put_failure; err = tcf_action_dump_1(skb, a, bind, ref); if (err < 0) goto errout; nla_nest_end(skb, nest); } return 0; nla_put_failure: err = -EINVAL; errout: nla_nest_cancel(skb, nest); return err; } static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb) { struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL); if (!c) return NULL; c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL); if (!c->data) { kfree(c); return NULL; } c->len = nla_len(tb[TCA_ACT_COOKIE]); return c; } static u8 tcf_action_hw_stats_get(struct nlattr *hw_stats_attr) { struct nla_bitfield32 hw_stats_bf; /* If the user did not pass the attr, that means he does * not care about the type. Return "any" in that case * which is setting on all supported types. */ if (!hw_stats_attr) return TCA_ACT_HW_STATS_ANY; hw_stats_bf = nla_get_bitfield32(hw_stats_attr); return hw_stats_bf.value; } static const u32 tca_act_flags_allowed = TCA_ACT_FLAGS_NO_PERCPU_STATS; static const u32 tca_act_hw_stats_allowed = TCA_ACT_HW_STATS_ANY; static const struct nla_policy tcf_action_policy[TCA_ACT_MAX + 1] = { [TCA_ACT_KIND] = { .type = NLA_STRING }, [TCA_ACT_INDEX] = { .type = NLA_U32 }, [TCA_ACT_COOKIE] = { .type = NLA_BINARY, .len = TC_COOKIE_MAX_SIZE }, [TCA_ACT_OPTIONS] = { .type = NLA_NESTED }, [TCA_ACT_FLAGS] = { .type = NLA_BITFIELD32, .validation_data = &tca_act_flags_allowed }, [TCA_ACT_HW_STATS] = { .type = NLA_BITFIELD32, .validation_data = &tca_act_hw_stats_allowed }, }; struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind, bool rtnl_held, struct netlink_ext_ack *extack) { struct nla_bitfield32 flags = { 0, 0 }; u8 hw_stats = TCA_ACT_HW_STATS_ANY; struct tc_action *a; struct tc_action_ops *a_o; struct tc_cookie *cookie = NULL; char act_name[IFNAMSIZ]; struct nlattr *tb[TCA_ACT_MAX + 1]; struct nlattr *kind; int err; if (name == NULL) { err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla, tcf_action_policy, extack); if (err < 0) goto err_out; err = -EINVAL; kind = tb[TCA_ACT_KIND]; if (!kind) { NL_SET_ERR_MSG(extack, "TC action kind must be specified"); goto err_out; } if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) { NL_SET_ERR_MSG(extack, "TC action name too long"); goto err_out; } if (tb[TCA_ACT_COOKIE]) { cookie = nla_memdup_cookie(tb); if (!cookie) { NL_SET_ERR_MSG(extack, "No memory to generate TC cookie"); err = -ENOMEM; goto err_out; } } hw_stats = tcf_action_hw_stats_get(tb[TCA_ACT_HW_STATS]); if (tb[TCA_ACT_FLAGS]) flags = nla_get_bitfield32(tb[TCA_ACT_FLAGS]); } else { if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) { NL_SET_ERR_MSG(extack, "TC action name too long"); err = -EINVAL; goto err_out; } } a_o = tc_lookup_action_n(act_name); if (a_o == NULL) { #ifdef CONFIG_MODULES if (rtnl_held) rtnl_unlock(); request_module("act_%s", act_name); if (rtnl_held) rtnl_lock(); a_o = tc_lookup_action_n(act_name); /* We dropped the RTNL semaphore in order to * perform the module load. So, even if we * succeeded in loading the module we have to * tell the caller to replay the request. We * indicate this using -EAGAIN. */ if (a_o != NULL) { err = -EAGAIN; goto err_mod; } #endif NL_SET_ERR_MSG(extack, "Failed to load TC action module"); err = -ENOENT; goto err_out; } /* backward compatibility for policer */ if (name == NULL) err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind, rtnl_held, tp, flags.value, extack); else err = a_o->init(net, nla, est, &a, ovr, bind, rtnl_held, tp, flags.value, extack); if (err < 0) goto err_mod; if (!name && tb[TCA_ACT_COOKIE]) tcf_set_action_cookie(&a->act_cookie, cookie); if (!name) a->hw_stats = hw_stats; /* module count goes up only when brand new policy is created * if it exists and is only bound to in a_o->init() then * ACT_P_CREATED is not returned (a zero is). */ if (err != ACT_P_CREATED) module_put(a_o->owner); if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN) && !rcu_access_pointer(a->goto_chain)) { tcf_action_destroy_1(a, bind); NL_SET_ERR_MSG(extack, "can't use goto chain with NULL chain"); return ERR_PTR(-EINVAL); } return a; err_mod: module_put(a_o->owner); err_out: if (cookie) { kfree(cookie->data); kfree(cookie); } return ERR_PTR(err); } /* Returns numbers of initialized actions or negative error. */ int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind, struct tc_action *actions[], size_t *attr_size, bool rtnl_held, struct netlink_ext_ack *extack) { struct nlattr *tb[TCA_ACT_MAX_PRIO + 1]; struct tc_action *act; size_t sz = 0; int err; int i; err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack); if (err < 0) return err; for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) { act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind, rtnl_held, extack); if (IS_ERR(act)) { err = PTR_ERR(act); goto err; } sz += tcf_action_fill_size(act); /* Start from index 0 */ actions[i - 1] = act; } *attr_size = tcf_action_full_attrs_size(sz); return i - 1; err: tcf_action_destroy(actions, bind); return err; } void tcf_action_update_stats(struct tc_action *a, u64 bytes, u32 packets, bool drop, bool hw) { if (a->cpu_bstats) { _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets); if (drop) this_cpu_ptr(a->cpu_qstats)->drops += packets; if (hw) _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats_hw), bytes, packets); return; } _bstats_update(&a->tcfa_bstats, bytes, packets); if (drop) a->tcfa_qstats.drops += packets; if (hw) _bstats_update(&a->tcfa_bstats_hw, bytes, packets); } EXPORT_SYMBOL(tcf_action_update_stats); int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p, int compat_mode) { int err = 0; struct gnet_dump d; if (p == NULL) goto errout; /* compat_mode being true specifies a call that is supposed * to add additional backward compatibility statistic TLVs. */ if (compat_mode) { if (p->type == TCA_OLD_COMPAT) err = gnet_stats_start_copy_compat(skb, 0, TCA_STATS, TCA_XSTATS, &p->tcfa_lock, &d, TCA_PAD); else return 0; } else err = gnet_stats_start_copy(skb, TCA_ACT_STATS, &p->tcfa_lock, &d, TCA_ACT_PAD); if (err < 0) goto errout; if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 || gnet_stats_copy_basic_hw(NULL, &d, p->cpu_bstats_hw, &p->tcfa_bstats_hw) < 0 || gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 || gnet_stats_copy_queue(&d, p->cpu_qstats, &p->tcfa_qstats, p->tcfa_qstats.qlen) < 0) goto errout; if (gnet_stats_finish_copy(&d) < 0) goto errout; return 0; errout: return -1; } static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[], u32 portid, u32 seq, u16 flags, int event, int bind, int ref) { struct tcamsg *t; struct nlmsghdr *nlh; unsigned char *b = skb_tail_pointer(skb); struct nlattr *nest; nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags); if (!nlh) goto out_nlmsg_trim; t = nlmsg_data(nlh); t->tca_family = AF_UNSPEC; t->tca__pad1 = 0; t->tca__pad2 = 0; nest = nla_nest_start_noflag(skb, TCA_ACT_TAB); if (!nest) goto out_nlmsg_trim; if (tcf_action_dump(skb, actions, bind, ref) < 0) goto out_nlmsg_trim; nla_nest_end(skb, nest); nlh->nlmsg_len = skb_tail_pointer(skb) - b; return skb->len; out_nlmsg_trim: nlmsg_trim(skb, b); return -1; } static int tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n, struct tc_action *actions[], int event, struct netlink_ext_ack *extack) { struct sk_buff *skb; skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return -ENOBUFS; if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event, 0, 1) <= 0) { NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action"); kfree_skb(skb); return -EINVAL; } return rtnl_unicast(skb, net, portid); } static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla, struct nlmsghdr *n, u32 portid, struct netlink_ext_ack *extack) { struct nlattr *tb[TCA_ACT_MAX + 1]; const struct tc_action_ops *ops; struct tc_action *a; int index; int err; err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla, tcf_action_policy, extack); if (err < 0) goto err_out; err = -EINVAL; if (tb[TCA_ACT_INDEX] == NULL || nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) { NL_SET_ERR_MSG(extack, "Invalid TC action index value"); goto err_out; } index = nla_get_u32(tb[TCA_ACT_INDEX]); err = -EINVAL; ops = tc_lookup_action(tb[TCA_ACT_KIND]); if (!ops) { /* could happen in batch of actions */ NL_SET_ERR_MSG(extack, "Specified TC action kind not found"); goto err_out; } err = -ENOENT; if (ops->lookup(net, &a, index) == 0) { NL_SET_ERR_MSG(extack, "TC action with specified index not found"); goto err_mod; } module_put(ops->owner); return a; err_mod: module_put(ops->owner); err_out: return ERR_PTR(err); } static int tca_action_flush(struct net *net, struct nlattr *nla, struct nlmsghdr *n, u32 portid, struct netlink_ext_ack *extack) { struct sk_buff *skb; unsigned char *b; struct nlmsghdr *nlh; struct tcamsg *t; struct netlink_callback dcb; struct nlattr *nest; struct nlattr *tb[TCA_ACT_MAX + 1]; const struct tc_action_ops *ops; struct nlattr *kind; int err = -ENOMEM; skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL); if (!skb) return err; b = skb_tail_pointer(skb); err = nla_parse_nested_deprecated(tb, TCA_ACT_MAX, nla, tcf_action_policy, extack); if (err < 0) goto err_out; err = -EINVAL; kind = tb[TCA_ACT_KIND]; ops = tc_lookup_action(kind); if (!ops) { /*some idjot trying to flush unknown action */ NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action"); goto err_out; } nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t), 0); if (!nlh) { NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification"); goto out_module_put; } t = nlmsg_data(nlh); t->tca_family = AF_UNSPEC; t->tca__pad1 = 0; t->tca__pad2 = 0; nest = nla_nest_start_noflag(skb, TCA_ACT_TAB); if (!nest) { NL_SET_ERR_MSG(extack, "Failed to add new netlink message"); goto out_module_put; } err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack); if (err <= 0) { nla_nest_cancel(skb, nest); goto out_module_put; } nla_nest_end(skb, nest); nlh->nlmsg_len = skb_tail_pointer(skb) - b; nlh->nlmsg_flags |= NLM_F_ROOT; module_put(ops->owner); err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, n->nlmsg_flags & NLM_F_ECHO); if (err > 0) return 0; if (err < 0) NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification"); return err; out_module_put: module_put(ops->owner); err_out: kfree_skb(skb); return err; } static int tcf_action_delete(struct net *net, struct tc_action *actions[]) { int i; for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) { struct tc_action *a = actions[i]; const struct tc_action_ops *ops = a->ops; /* Actions can be deleted concurrently so we must save their * type and id to search again after reference is released. */ struct tcf_idrinfo *idrinfo = a->idrinfo; u32 act_index = a->tcfa_index; actions[i] = NULL; if (tcf_action_put(a)) { /* last reference, action was deleted concurrently */ module_put(ops->owner); } else { int ret; /* now do the delete */ ret = tcf_idr_delete_index(idrinfo, act_index); if (ret < 0) return ret; } } return 0; } static int tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[], u32 portid, size_t attr_size, struct netlink_ext_ack *extack) { int ret; struct sk_buff *skb; skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size, GFP_KERNEL); if (!skb) return -ENOBUFS; if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION, 0, 2) <= 0) { NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes"); kfree_skb(skb); return -EINVAL; } /* now do the delete */ ret = tcf_action_delete(net, actions); if (ret < 0) { NL_SET_ERR_MSG(extack, "Failed to delete TC action"); kfree_skb(skb); return ret; } ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC, n->nlmsg_flags & NLM_F_ECHO); if (ret > 0) return 0; return ret; } static int tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n, u32 portid, int event, struct netlink_ext_ack *extack) { int i, ret; struct nlattr *tb[TCA_ACT_MAX_PRIO + 1]; struct tc_action *act; size_t attr_size = 0; struct tc_action *actions[TCA_ACT_MAX_PRIO] = {}; ret = nla_parse_nested_deprecated(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack); if (ret < 0) return ret; if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) { if (tb[1]) return tca_action_flush(net, tb[1], n, portid, extack); NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action"); return -EINVAL; } for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) { act = tcf_action_get_1(net, tb[i], n, portid, extack); if (IS_ERR(act)) { ret = PTR_ERR(act); goto err; } attr_size += tcf_action_fill_size(act); actions[i - 1] = act; } attr_size = tcf_action_full_attrs_size(attr_size); if (event == RTM_GETACTION) ret = tcf_get_notify(net, portid, n, actions, event, extack); else { /* delete */ ret = tcf_del_notify(net, n, actions, portid, attr_size, extack); if (ret) goto err; return 0; } err: tcf_action_put_many(actions); return ret; } static int tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[], u32 portid, size_t attr_size, struct netlink_ext_ack *extack) { struct sk_buff *skb; int err = 0; skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size, GFP_KERNEL); if (!skb) return -ENOBUFS; if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags, RTM_NEWACTION, 0, 0) <= 0) { NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action"); kfree_skb(skb); return -EINVAL; } err = rtnetlink_send(skb, net, portid, RTNLGRP_TC, n->nlmsg_flags & NLM_F_ECHO); if (err > 0) err = 0; return err; } static int tcf_action_add(struct net *net, struct nlattr *nla, struct nlmsghdr *n, u32 portid, int ovr, struct netlink_ext_ack *extack) { size_t attr_size = 0; int loop, ret; struct tc_action *actions[TCA_ACT_MAX_PRIO] = {}; for (loop = 0; loop < 10; loop++) { ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0, actions, &attr_size, true, extack); if (ret != -EAGAIN) break; } if (ret < 0) return ret; ret = tcf_add_notify(net, n, actions, portid, attr_size, extack); if (ovr) tcf_action_put_many(actions); return ret; } static u32 tcaa_root_flags_allowed = TCA_FLAG_LARGE_DUMP_ON; static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = { [TCA_ROOT_FLAGS] = { .type = NLA_BITFIELD32, .validation_data = &tcaa_root_flags_allowed }, [TCA_ROOT_TIME_DELTA] = { .type = NLA_U32 }, }; static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, struct netlink_ext_ack *extack) { struct net *net = sock_net(skb->sk); struct nlattr *tca[TCA_ROOT_MAX + 1]; u32 portid = skb ? NETLINK_CB(skb).portid : 0; int ret = 0, ovr = 0; if ((n->nlmsg_type != RTM_GETACTION) && !netlink_capable(skb, CAP_NET_ADMIN)) return -EPERM; ret = nlmsg_parse_deprecated(n, sizeof(struct tcamsg), tca, TCA_ROOT_MAX, NULL, extack); if (ret < 0) return ret; if (tca[TCA_ACT_TAB] == NULL) { NL_SET_ERR_MSG(extack, "Netlink action attributes missing"); return -EINVAL; } /* n->nlmsg_flags & NLM_F_CREATE */ switch (n->nlmsg_type) { case RTM_NEWACTION: /* we are going to assume all other flags * imply create only if it doesn't exist * Note that CREATE | EXCL implies that * but since we want avoid ambiguity (eg when flags * is zero) then just set this */ if (n->nlmsg_flags & NLM_F_REPLACE) ovr = 1; ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr, extack); break; case RTM_DELACTION: ret = tca_action_gd(net, tca[TCA_ACT_TAB], n, portid, RTM_DELACTION, extack); break; case RTM_GETACTION: ret = tca_action_gd(net, tca[TCA_ACT_TAB], n, portid, RTM_GETACTION, extack); break; default: BUG(); } return ret; } static struct nlattr *find_dump_kind(struct nlattr **nla) { struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1]; struct nlattr *tb[TCA_ACT_MAX_PRIO + 1]; struct nlattr *kind; tb1 = nla[TCA_ACT_TAB]; if (tb1 == NULL) return NULL; if (nla_parse_deprecated(tb, TCA_ACT_MAX_PRIO, nla_data(tb1), NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0) return NULL; if (tb[1] == NULL) return NULL; if (nla_parse_nested_deprecated(tb2, TCA_ACT_MAX, tb[1], tcf_action_policy, NULL) < 0) return NULL; kind = tb2[TCA_ACT_KIND]; return kind; } static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb) { struct net *net = sock_net(skb->sk); struct nlmsghdr *nlh; unsigned char *b = skb_tail_pointer(skb); struct nlattr *nest; struct tc_action_ops *a_o; int ret = 0; struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh); struct nlattr *tb[TCA_ROOT_MAX + 1]; struct nlattr *count_attr = NULL; unsigned long jiffy_since = 0; struct nlattr *kind = NULL; struct nla_bitfield32 bf; u32 msecs_since = 0; u32 act_count = 0; ret = nlmsg_parse_deprecated(cb->nlh, sizeof(struct tcamsg), tb, TCA_ROOT_MAX, tcaa_policy, cb->extack); if (ret < 0) return ret; kind = find_dump_kind(tb); if (kind == NULL) { pr_info("tc_dump_action: action bad kind\n"); return 0; } a_o = tc_lookup_action(kind); if (a_o == NULL) return 0; cb->args[2] = 0; if (tb[TCA_ROOT_FLAGS]) { bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]); cb->args[2] = bf.value; } if (tb[TCA_ROOT_TIME_DELTA]) { msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]); } nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq, cb->nlh->nlmsg_type, sizeof(*t), 0); if (!nlh) goto out_module_put; if (msecs_since) jiffy_since = jiffies - msecs_to_jiffies(msecs_since); t = nlmsg_data(nlh); t->tca_family = AF_UNSPEC; t->tca__pad1 = 0; t->tca__pad2 = 0; cb->args[3] = jiffy_since; count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32)); if (!count_attr) goto out_module_put; nest = nla_nest_start_noflag(skb, TCA_ACT_TAB); if (nest == NULL) goto out_module_put; ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL); if (ret < 0) goto out_module_put; if (ret > 0) { nla_nest_end(skb, nest); ret = skb->len; act_count = cb->args[1]; memcpy(nla_data(count_attr), &act_count, sizeof(u32)); cb->args[1] = 0; } else nlmsg_trim(skb, b); nlh->nlmsg_len = skb_tail_pointer(skb) - b; if (NETLINK_CB(cb->skb).portid && ret) nlh->nlmsg_flags |= NLM_F_MULTI; module_put(a_o->owner); return skb->len; out_module_put: module_put(a_o->owner); nlmsg_trim(skb, b); return skb->len; } static int __init tc_action_init(void) { rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0); rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0); rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action, 0); return 0; } subsys_initcall(tc_action_init);