|  | // SPDX-License-Identifier: GPL-2.0-or-later | 
|  | /* | 
|  | * net/sched/act_police.c	Input police filter | 
|  | * | 
|  | * Authors:	Alexey Kuznetsov, <[email protected]> | 
|  | * 		J Hadi Salim (action changes) | 
|  | */ | 
|  |  | 
|  | #include <linux/module.h> | 
|  | #include <linux/types.h> | 
|  | #include <linux/kernel.h> | 
|  | #include <linux/string.h> | 
|  | #include <linux/errno.h> | 
|  | #include <linux/skbuff.h> | 
|  | #include <linux/rtnetlink.h> | 
|  | #include <linux/init.h> | 
|  | #include <linux/slab.h> | 
|  | #include <net/act_api.h> | 
|  | #include <net/netlink.h> | 
|  | #include <net/pkt_cls.h> | 
|  | #include <net/tc_act/tc_police.h> | 
|  |  | 
|  | /* Each policer is serialized by its individual spinlock */ | 
|  |  | 
|  | static unsigned int police_net_id; | 
|  | static struct tc_action_ops act_police_ops; | 
|  |  | 
|  | static int tcf_police_walker(struct net *net, struct sk_buff *skb, | 
|  | struct netlink_callback *cb, int type, | 
|  | const struct tc_action_ops *ops, | 
|  | struct netlink_ext_ack *extack) | 
|  | { | 
|  | struct tc_action_net *tn = net_generic(net, police_net_id); | 
|  |  | 
|  | return tcf_generic_walker(tn, skb, cb, type, ops, extack); | 
|  | } | 
|  |  | 
|  | static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = { | 
|  | [TCA_POLICE_RATE]	= { .len = TC_RTAB_SIZE }, | 
|  | [TCA_POLICE_PEAKRATE]	= { .len = TC_RTAB_SIZE }, | 
|  | [TCA_POLICE_AVRATE]	= { .type = NLA_U32 }, | 
|  | [TCA_POLICE_RESULT]	= { .type = NLA_U32 }, | 
|  | [TCA_POLICE_RATE64]     = { .type = NLA_U64 }, | 
|  | [TCA_POLICE_PEAKRATE64] = { .type = NLA_U64 }, | 
|  | }; | 
|  |  | 
|  | static int tcf_police_init(struct net *net, struct nlattr *nla, | 
|  | struct nlattr *est, struct tc_action **a, | 
|  | int ovr, int bind, bool rtnl_held, | 
|  | struct tcf_proto *tp, u32 flags, | 
|  | struct netlink_ext_ack *extack) | 
|  | { | 
|  | int ret = 0, tcfp_result = TC_ACT_OK, err, size; | 
|  | struct nlattr *tb[TCA_POLICE_MAX + 1]; | 
|  | struct tcf_chain *goto_ch = NULL; | 
|  | struct tc_police *parm; | 
|  | struct tcf_police *police; | 
|  | struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL; | 
|  | struct tc_action_net *tn = net_generic(net, police_net_id); | 
|  | struct tcf_police_params *new; | 
|  | bool exists = false; | 
|  | u32 index; | 
|  | u64 rate64, prate64; | 
|  |  | 
|  | if (nla == NULL) | 
|  | return -EINVAL; | 
|  |  | 
|  | err = nla_parse_nested_deprecated(tb, TCA_POLICE_MAX, nla, | 
|  | police_policy, NULL); | 
|  | if (err < 0) | 
|  | return err; | 
|  |  | 
|  | if (tb[TCA_POLICE_TBF] == NULL) | 
|  | return -EINVAL; | 
|  | size = nla_len(tb[TCA_POLICE_TBF]); | 
|  | if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat)) | 
|  | return -EINVAL; | 
|  |  | 
|  | parm = nla_data(tb[TCA_POLICE_TBF]); | 
|  | index = parm->index; | 
|  | err = tcf_idr_check_alloc(tn, &index, a, bind); | 
|  | if (err < 0) | 
|  | return err; | 
|  | exists = err; | 
|  | if (exists && bind) | 
|  | return 0; | 
|  |  | 
|  | if (!exists) { | 
|  | ret = tcf_idr_create(tn, index, NULL, a, | 
|  | &act_police_ops, bind, true, 0); | 
|  | if (ret) { | 
|  | tcf_idr_cleanup(tn, index); | 
|  | return ret; | 
|  | } | 
|  | ret = ACT_P_CREATED; | 
|  | spin_lock_init(&(to_police(*a)->tcfp_lock)); | 
|  | } else if (!ovr) { | 
|  | tcf_idr_release(*a, bind); | 
|  | return -EEXIST; | 
|  | } | 
|  | err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); | 
|  | if (err < 0) | 
|  | goto release_idr; | 
|  |  | 
|  | police = to_police(*a); | 
|  | if (parm->rate.rate) { | 
|  | err = -ENOMEM; | 
|  | R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE], NULL); | 
|  | if (R_tab == NULL) | 
|  | goto failure; | 
|  |  | 
|  | if (parm->peakrate.rate) { | 
|  | P_tab = qdisc_get_rtab(&parm->peakrate, | 
|  | tb[TCA_POLICE_PEAKRATE], NULL); | 
|  | if (P_tab == NULL) | 
|  | goto failure; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (est) { | 
|  | err = gen_replace_estimator(&police->tcf_bstats, | 
|  | police->common.cpu_bstats, | 
|  | &police->tcf_rate_est, | 
|  | &police->tcf_lock, | 
|  | NULL, est); | 
|  | if (err) | 
|  | goto failure; | 
|  | } else if (tb[TCA_POLICE_AVRATE] && | 
|  | (ret == ACT_P_CREATED || | 
|  | !gen_estimator_active(&police->tcf_rate_est))) { | 
|  | err = -EINVAL; | 
|  | goto failure; | 
|  | } | 
|  |  | 
|  | if (tb[TCA_POLICE_RESULT]) { | 
|  | tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]); | 
|  | if (TC_ACT_EXT_CMP(tcfp_result, TC_ACT_GOTO_CHAIN)) { | 
|  | NL_SET_ERR_MSG(extack, | 
|  | "goto chain not allowed on fallback"); | 
|  | err = -EINVAL; | 
|  | goto failure; | 
|  | } | 
|  | } | 
|  |  | 
|  | new = kzalloc(sizeof(*new), GFP_KERNEL); | 
|  | if (unlikely(!new)) { | 
|  | err = -ENOMEM; | 
|  | goto failure; | 
|  | } | 
|  |  | 
|  | /* No failure allowed after this point */ | 
|  | new->tcfp_result = tcfp_result; | 
|  | new->tcfp_mtu = parm->mtu; | 
|  | if (!new->tcfp_mtu) { | 
|  | new->tcfp_mtu = ~0; | 
|  | if (R_tab) | 
|  | new->tcfp_mtu = 255 << R_tab->rate.cell_log; | 
|  | } | 
|  | if (R_tab) { | 
|  | new->rate_present = true; | 
|  | rate64 = tb[TCA_POLICE_RATE64] ? | 
|  | nla_get_u64(tb[TCA_POLICE_RATE64]) : 0; | 
|  | psched_ratecfg_precompute(&new->rate, &R_tab->rate, rate64); | 
|  | qdisc_put_rtab(R_tab); | 
|  | } else { | 
|  | new->rate_present = false; | 
|  | } | 
|  | if (P_tab) { | 
|  | new->peak_present = true; | 
|  | prate64 = tb[TCA_POLICE_PEAKRATE64] ? | 
|  | nla_get_u64(tb[TCA_POLICE_PEAKRATE64]) : 0; | 
|  | psched_ratecfg_precompute(&new->peak, &P_tab->rate, prate64); | 
|  | qdisc_put_rtab(P_tab); | 
|  | } else { | 
|  | new->peak_present = false; | 
|  | } | 
|  |  | 
|  | new->tcfp_burst = PSCHED_TICKS2NS(parm->burst); | 
|  | if (new->peak_present) | 
|  | new->tcfp_mtu_ptoks = (s64)psched_l2t_ns(&new->peak, | 
|  | new->tcfp_mtu); | 
|  |  | 
|  | if (tb[TCA_POLICE_AVRATE]) | 
|  | new->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]); | 
|  |  | 
|  | spin_lock_bh(&police->tcf_lock); | 
|  | spin_lock_bh(&police->tcfp_lock); | 
|  | police->tcfp_t_c = ktime_get_ns(); | 
|  | police->tcfp_toks = new->tcfp_burst; | 
|  | if (new->peak_present) | 
|  | police->tcfp_ptoks = new->tcfp_mtu_ptoks; | 
|  | spin_unlock_bh(&police->tcfp_lock); | 
|  | goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); | 
|  | new = rcu_replace_pointer(police->params, | 
|  | new, | 
|  | lockdep_is_held(&police->tcf_lock)); | 
|  | spin_unlock_bh(&police->tcf_lock); | 
|  |  | 
|  | if (goto_ch) | 
|  | tcf_chain_put_by_act(goto_ch); | 
|  | if (new) | 
|  | kfree_rcu(new, rcu); | 
|  |  | 
|  | if (ret == ACT_P_CREATED) | 
|  | tcf_idr_insert(tn, *a); | 
|  | return ret; | 
|  |  | 
|  | failure: | 
|  | qdisc_put_rtab(P_tab); | 
|  | qdisc_put_rtab(R_tab); | 
|  | if (goto_ch) | 
|  | tcf_chain_put_by_act(goto_ch); | 
|  | release_idr: | 
|  | tcf_idr_release(*a, bind); | 
|  | return err; | 
|  | } | 
|  |  | 
|  | static int tcf_police_act(struct sk_buff *skb, const struct tc_action *a, | 
|  | struct tcf_result *res) | 
|  | { | 
|  | struct tcf_police *police = to_police(a); | 
|  | struct tcf_police_params *p; | 
|  | s64 now, toks, ptoks = 0; | 
|  | int ret; | 
|  |  | 
|  | tcf_lastuse_update(&police->tcf_tm); | 
|  | bstats_cpu_update(this_cpu_ptr(police->common.cpu_bstats), skb); | 
|  |  | 
|  | ret = READ_ONCE(police->tcf_action); | 
|  | p = rcu_dereference_bh(police->params); | 
|  |  | 
|  | if (p->tcfp_ewma_rate) { | 
|  | struct gnet_stats_rate_est64 sample; | 
|  |  | 
|  | if (!gen_estimator_read(&police->tcf_rate_est, &sample) || | 
|  | sample.bps >= p->tcfp_ewma_rate) | 
|  | goto inc_overlimits; | 
|  | } | 
|  |  | 
|  | if (qdisc_pkt_len(skb) <= p->tcfp_mtu) { | 
|  | if (!p->rate_present) { | 
|  | ret = p->tcfp_result; | 
|  | goto end; | 
|  | } | 
|  |  | 
|  | now = ktime_get_ns(); | 
|  | spin_lock_bh(&police->tcfp_lock); | 
|  | toks = min_t(s64, now - police->tcfp_t_c, p->tcfp_burst); | 
|  | if (p->peak_present) { | 
|  | ptoks = toks + police->tcfp_ptoks; | 
|  | if (ptoks > p->tcfp_mtu_ptoks) | 
|  | ptoks = p->tcfp_mtu_ptoks; | 
|  | ptoks -= (s64)psched_l2t_ns(&p->peak, | 
|  | qdisc_pkt_len(skb)); | 
|  | } | 
|  | toks += police->tcfp_toks; | 
|  | if (toks > p->tcfp_burst) | 
|  | toks = p->tcfp_burst; | 
|  | toks -= (s64)psched_l2t_ns(&p->rate, qdisc_pkt_len(skb)); | 
|  | if ((toks|ptoks) >= 0) { | 
|  | police->tcfp_t_c = now; | 
|  | police->tcfp_toks = toks; | 
|  | police->tcfp_ptoks = ptoks; | 
|  | spin_unlock_bh(&police->tcfp_lock); | 
|  | ret = p->tcfp_result; | 
|  | goto inc_drops; | 
|  | } | 
|  | spin_unlock_bh(&police->tcfp_lock); | 
|  | } | 
|  |  | 
|  | inc_overlimits: | 
|  | qstats_overlimit_inc(this_cpu_ptr(police->common.cpu_qstats)); | 
|  | inc_drops: | 
|  | if (ret == TC_ACT_SHOT) | 
|  | qstats_drop_inc(this_cpu_ptr(police->common.cpu_qstats)); | 
|  | end: | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static void tcf_police_cleanup(struct tc_action *a) | 
|  | { | 
|  | struct tcf_police *police = to_police(a); | 
|  | struct tcf_police_params *p; | 
|  |  | 
|  | p = rcu_dereference_protected(police->params, 1); | 
|  | if (p) | 
|  | kfree_rcu(p, rcu); | 
|  | } | 
|  |  | 
|  | static void tcf_police_stats_update(struct tc_action *a, | 
|  | u64 bytes, u64 packets, u64 drops, | 
|  | u64 lastuse, bool hw) | 
|  | { | 
|  | struct tcf_police *police = to_police(a); | 
|  | struct tcf_t *tm = &police->tcf_tm; | 
|  |  | 
|  | tcf_action_update_stats(a, bytes, packets, drops, hw); | 
|  | tm->lastuse = max_t(u64, tm->lastuse, lastuse); | 
|  | } | 
|  |  | 
|  | static int tcf_police_dump(struct sk_buff *skb, struct tc_action *a, | 
|  | int bind, int ref) | 
|  | { | 
|  | unsigned char *b = skb_tail_pointer(skb); | 
|  | struct tcf_police *police = to_police(a); | 
|  | struct tcf_police_params *p; | 
|  | struct tc_police opt = { | 
|  | .index = police->tcf_index, | 
|  | .refcnt = refcount_read(&police->tcf_refcnt) - ref, | 
|  | .bindcnt = atomic_read(&police->tcf_bindcnt) - bind, | 
|  | }; | 
|  | struct tcf_t t; | 
|  |  | 
|  | spin_lock_bh(&police->tcf_lock); | 
|  | opt.action = police->tcf_action; | 
|  | p = rcu_dereference_protected(police->params, | 
|  | lockdep_is_held(&police->tcf_lock)); | 
|  | opt.mtu = p->tcfp_mtu; | 
|  | opt.burst = PSCHED_NS2TICKS(p->tcfp_burst); | 
|  | if (p->rate_present) { | 
|  | psched_ratecfg_getrate(&opt.rate, &p->rate); | 
|  | if ((police->params->rate.rate_bytes_ps >= (1ULL << 32)) && | 
|  | nla_put_u64_64bit(skb, TCA_POLICE_RATE64, | 
|  | police->params->rate.rate_bytes_ps, | 
|  | TCA_POLICE_PAD)) | 
|  | goto nla_put_failure; | 
|  | } | 
|  | if (p->peak_present) { | 
|  | psched_ratecfg_getrate(&opt.peakrate, &p->peak); | 
|  | if ((police->params->peak.rate_bytes_ps >= (1ULL << 32)) && | 
|  | nla_put_u64_64bit(skb, TCA_POLICE_PEAKRATE64, | 
|  | police->params->peak.rate_bytes_ps, | 
|  | TCA_POLICE_PAD)) | 
|  | goto nla_put_failure; | 
|  | } | 
|  | if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt)) | 
|  | goto nla_put_failure; | 
|  | if (p->tcfp_result && | 
|  | nla_put_u32(skb, TCA_POLICE_RESULT, p->tcfp_result)) | 
|  | goto nla_put_failure; | 
|  | if (p->tcfp_ewma_rate && | 
|  | nla_put_u32(skb, TCA_POLICE_AVRATE, p->tcfp_ewma_rate)) | 
|  | goto nla_put_failure; | 
|  |  | 
|  | tcf_tm_dump(&t, &police->tcf_tm); | 
|  | if (nla_put_64bit(skb, TCA_POLICE_TM, sizeof(t), &t, TCA_POLICE_PAD)) | 
|  | goto nla_put_failure; | 
|  | spin_unlock_bh(&police->tcf_lock); | 
|  |  | 
|  | return skb->len; | 
|  |  | 
|  | nla_put_failure: | 
|  | spin_unlock_bh(&police->tcf_lock); | 
|  | nlmsg_trim(skb, b); | 
|  | return -1; | 
|  | } | 
|  |  | 
|  | static int tcf_police_search(struct net *net, struct tc_action **a, u32 index) | 
|  | { | 
|  | struct tc_action_net *tn = net_generic(net, police_net_id); | 
|  |  | 
|  | return tcf_idr_search(tn, a, index); | 
|  | } | 
|  |  | 
|  | MODULE_AUTHOR("Alexey Kuznetsov"); | 
|  | MODULE_DESCRIPTION("Policing actions"); | 
|  | MODULE_LICENSE("GPL"); | 
|  |  | 
|  | static struct tc_action_ops act_police_ops = { | 
|  | .kind		=	"police", | 
|  | .id		=	TCA_ID_POLICE, | 
|  | .owner		=	THIS_MODULE, | 
|  | .stats_update	=	tcf_police_stats_update, | 
|  | .act		=	tcf_police_act, | 
|  | .dump		=	tcf_police_dump, | 
|  | .init		=	tcf_police_init, | 
|  | .walk		=	tcf_police_walker, | 
|  | .lookup		=	tcf_police_search, | 
|  | .cleanup	=	tcf_police_cleanup, | 
|  | .size		=	sizeof(struct tcf_police), | 
|  | }; | 
|  |  | 
|  | static __net_init int police_init_net(struct net *net) | 
|  | { | 
|  | struct tc_action_net *tn = net_generic(net, police_net_id); | 
|  |  | 
|  | return tc_action_net_init(net, tn, &act_police_ops); | 
|  | } | 
|  |  | 
|  | static void __net_exit police_exit_net(struct list_head *net_list) | 
|  | { | 
|  | tc_action_net_exit(net_list, police_net_id); | 
|  | } | 
|  |  | 
|  | static struct pernet_operations police_net_ops = { | 
|  | .init = police_init_net, | 
|  | .exit_batch = police_exit_net, | 
|  | .id   = &police_net_id, | 
|  | .size = sizeof(struct tc_action_net), | 
|  | }; | 
|  |  | 
|  | static int __init police_init_module(void) | 
|  | { | 
|  | return tcf_register_action(&act_police_ops, &police_net_ops); | 
|  | } | 
|  |  | 
|  | static void __exit police_cleanup_module(void) | 
|  | { | 
|  | tcf_unregister_action(&act_police_ops, &police_net_ops); | 
|  | } | 
|  |  | 
|  | module_init(police_init_module); | 
|  | module_exit(police_cleanup_module); |