1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * net/sched/act_police.c Input police filter
4 *
5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6 * J Hadi Salim (action changes)
7 */
8
9 #include <linux/module.h>
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/errno.h>
14 #include <linux/skbuff.h>
15 #include <linux/rtnetlink.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <net/act_api.h>
19 #include <net/gso.h>
20 #include <net/netlink.h>
21 #include <net/pkt_cls.h>
22 #include <net/tc_act/tc_police.h>
23 #include <net/tc_wrapper.h>
24
25 /* Each policer is serialized by its individual spinlock */
26
27 static struct tc_action_ops act_police_ops;
28
29 static const struct nla_policy police_policy[TCA_POLICE_MAX + 1] = {
30 [TCA_POLICE_RATE] = { .len = TC_RTAB_SIZE },
31 [TCA_POLICE_PEAKRATE] = { .len = TC_RTAB_SIZE },
32 [TCA_POLICE_AVRATE] = { .type = NLA_U32 },
33 [TCA_POLICE_RESULT] = { .type = NLA_U32 },
34 [TCA_POLICE_RATE64] = { .type = NLA_U64 },
35 [TCA_POLICE_PEAKRATE64] = { .type = NLA_U64 },
36 [TCA_POLICE_PKTRATE64] = { .type = NLA_U64, .min = 1 },
37 [TCA_POLICE_PKTBURST64] = { .type = NLA_U64, .min = 1 },
38 };
39
tcf_police_init(struct net * net,struct nlattr * nla,struct nlattr * est,struct tc_action ** a,struct tcf_proto * tp,u32 flags,struct netlink_ext_ack * extack)40 static int tcf_police_init(struct net *net, struct nlattr *nla,
41 struct nlattr *est, struct tc_action **a,
42 struct tcf_proto *tp, u32 flags,
43 struct netlink_ext_ack *extack)
44 {
45 int ret = 0, tcfp_result = TC_ACT_OK, err, size;
46 bool bind = flags & TCA_ACT_FLAGS_BIND;
47 struct nlattr *tb[TCA_POLICE_MAX + 1];
48 struct tcf_chain *goto_ch = NULL;
49 struct tc_police *parm;
50 struct tcf_police *police;
51 struct qdisc_rate_table *R_tab = NULL, *P_tab = NULL;
52 struct tc_action_net *tn = net_generic(net, act_police_ops.net_id);
53 struct tcf_police_params *new;
54 bool exists = false;
55 u32 index;
56 u64 rate64, prate64;
57 u64 pps, ppsburst;
58
59 if (nla == NULL)
60 return -EINVAL;
61
62 err = nla_parse_nested_deprecated(tb, TCA_POLICE_MAX, nla,
63 police_policy, NULL);
64 if (err < 0)
65 return err;
66
67 if (tb[TCA_POLICE_TBF] == NULL)
68 return -EINVAL;
69 size = nla_len(tb[TCA_POLICE_TBF]);
70 if (size != sizeof(*parm) && size != sizeof(struct tc_police_compat))
71 return -EINVAL;
72
73 parm = nla_data(tb[TCA_POLICE_TBF]);
74 index = parm->index;
75 err = tcf_idr_check_alloc(tn, &index, a, bind);
76 if (err < 0)
77 return err;
78 exists = err;
79 if (exists && bind)
80 return ACT_P_BOUND;
81
82 if (!exists) {
83 ret = tcf_idr_create(tn, index, NULL, a,
84 &act_police_ops, bind, true, flags);
85 if (ret) {
86 tcf_idr_cleanup(tn, index);
87 return ret;
88 }
89 ret = ACT_P_CREATED;
90 spin_lock_init(&(to_police(*a)->tcfp_lock));
91 } else if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
92 tcf_idr_release(*a, bind);
93 return -EEXIST;
94 }
95 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
96 if (err < 0)
97 goto release_idr;
98
99 police = to_police(*a);
100 if (parm->rate.rate) {
101 err = -ENOMEM;
102 R_tab = qdisc_get_rtab(&parm->rate, tb[TCA_POLICE_RATE], NULL);
103 if (R_tab == NULL)
104 goto failure;
105
106 if (parm->peakrate.rate) {
107 P_tab = qdisc_get_rtab(&parm->peakrate,
108 tb[TCA_POLICE_PEAKRATE], NULL);
109 if (P_tab == NULL)
110 goto failure;
111 }
112 }
113
114 if (est) {
115 err = gen_replace_estimator(&police->tcf_bstats,
116 police->common.cpu_bstats,
117 &police->tcf_rate_est,
118 &police->tcf_lock,
119 false, est);
120 if (err)
121 goto failure;
122 } else if (tb[TCA_POLICE_AVRATE] &&
123 (ret == ACT_P_CREATED ||
124 !gen_estimator_active(&police->tcf_rate_est))) {
125 err = -EINVAL;
126 goto failure;
127 }
128
129 if (tb[TCA_POLICE_RESULT]) {
130 tcfp_result = nla_get_u32(tb[TCA_POLICE_RESULT]);
131 if (!tcf_action_valid(tcfp_result)) {
132 NL_SET_ERR_MSG(extack,
133 "invalid fallback control action");
134 err = -EINVAL;
135 goto failure;
136 }
137 if (TC_ACT_EXT_CMP(tcfp_result, TC_ACT_GOTO_CHAIN)) {
138 NL_SET_ERR_MSG(extack,
139 "goto chain not allowed on fallback");
140 err = -EINVAL;
141 goto failure;
142 }
143 }
144
145 if ((tb[TCA_POLICE_PKTRATE64] && !tb[TCA_POLICE_PKTBURST64]) ||
146 (!tb[TCA_POLICE_PKTRATE64] && tb[TCA_POLICE_PKTBURST64])) {
147 NL_SET_ERR_MSG(extack,
148 "Both or neither packet-per-second burst and rate must be provided");
149 err = -EINVAL;
150 goto failure;
151 }
152
153 if (tb[TCA_POLICE_PKTRATE64] && R_tab) {
154 NL_SET_ERR_MSG(extack,
155 "packet-per-second and byte-per-second rate limits not allowed in same action");
156 err = -EINVAL;
157 goto failure;
158 }
159
160 new = kzalloc_obj(*new);
161 if (unlikely(!new)) {
162 err = -ENOMEM;
163 goto failure;
164 }
165
166 /* No failure allowed after this point */
167 new->tcfp_result = tcfp_result;
168 new->tcfp_mtu = parm->mtu;
169 if (!new->tcfp_mtu) {
170 new->tcfp_mtu = ~0;
171 if (R_tab)
172 new->tcfp_mtu = 255 << R_tab->rate.cell_log;
173 }
174 if (R_tab) {
175 new->rate_present = true;
176 rate64 = nla_get_u64_default(tb[TCA_POLICE_RATE64], 0);
177 psched_ratecfg_precompute(&new->rate, &R_tab->rate, rate64);
178 qdisc_put_rtab(R_tab);
179 } else {
180 new->rate_present = false;
181 }
182 if (P_tab) {
183 new->peak_present = true;
184 prate64 = nla_get_u64_default(tb[TCA_POLICE_PEAKRATE64], 0);
185 psched_ratecfg_precompute(&new->peak, &P_tab->rate, prate64);
186 qdisc_put_rtab(P_tab);
187 } else {
188 new->peak_present = false;
189 }
190
191 new->tcfp_burst = PSCHED_TICKS2NS(parm->burst);
192 if (new->peak_present)
193 new->tcfp_mtu_ptoks = (s64)psched_l2t_ns(&new->peak,
194 new->tcfp_mtu);
195
196 if (tb[TCA_POLICE_AVRATE])
197 new->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]);
198
199 if (tb[TCA_POLICE_PKTRATE64]) {
200 pps = nla_get_u64(tb[TCA_POLICE_PKTRATE64]);
201 ppsburst = nla_get_u64(tb[TCA_POLICE_PKTBURST64]);
202 new->pps_present = true;
203 new->tcfp_pkt_burst = PSCHED_TICKS2NS(ppsburst);
204 psched_ppscfg_precompute(&new->ppsrate, pps);
205 }
206
207 new->action = parm->action;
208 spin_lock_bh(&police->tcf_lock);
209 spin_lock_bh(&police->tcfp_lock);
210 police->tcfp_t_c = ktime_get_ns();
211 police->tcfp_toks = new->tcfp_burst;
212 if (new->peak_present)
213 police->tcfp_ptoks = new->tcfp_mtu_ptoks;
214 spin_unlock_bh(&police->tcfp_lock);
215 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
216 new = rcu_replace_pointer(police->params,
217 new,
218 lockdep_is_held(&police->tcf_lock));
219 spin_unlock_bh(&police->tcf_lock);
220
221 if (goto_ch)
222 tcf_chain_put_by_act(goto_ch);
223 if (new)
224 kfree_rcu(new, rcu);
225
226 return ret;
227
228 failure:
229 qdisc_put_rtab(P_tab);
230 qdisc_put_rtab(R_tab);
231 if (goto_ch)
232 tcf_chain_put_by_act(goto_ch);
233 release_idr:
234 tcf_idr_release(*a, bind);
235 return err;
236 }
237
tcf_police_mtu_check(struct sk_buff * skb,u32 limit)238 static bool tcf_police_mtu_check(struct sk_buff *skb, u32 limit)
239 {
240 u32 len;
241
242 if (skb_is_gso(skb))
243 return skb_gso_validate_mac_len(skb, limit);
244
245 len = qdisc_pkt_len(skb);
246 if (skb_at_tc_ingress(skb))
247 len += skb->mac_len;
248
249 return len <= limit;
250 }
251
tcf_police_act(struct sk_buff * skb,const struct tc_action * a,struct tcf_result * res)252 TC_INDIRECT_SCOPE int tcf_police_act(struct sk_buff *skb,
253 const struct tc_action *a,
254 struct tcf_result *res)
255 {
256 struct tcf_police *police = to_police(a);
257 s64 now, toks, ppstoks = 0, ptoks = 0;
258 struct tcf_police_params *p;
259 int ret;
260
261 tcf_lastuse_update(&police->tcf_tm);
262 bstats_update(this_cpu_ptr(police->common.cpu_bstats), skb);
263
264 p = rcu_dereference_bh(police->params);
265 ret = p->action;
266
267 if (p->tcfp_ewma_rate) {
268 struct gnet_stats_rate_est64 sample;
269
270 if (!gen_estimator_read(&police->tcf_rate_est, &sample) ||
271 sample.bps >= p->tcfp_ewma_rate)
272 goto inc_overlimits;
273 }
274
275 if (tcf_police_mtu_check(skb, p->tcfp_mtu)) {
276 if (!p->rate_present && !p->pps_present) {
277 ret = p->tcfp_result;
278 goto end;
279 }
280
281 now = ktime_get_ns();
282 spin_lock_bh(&police->tcfp_lock);
283 toks = min_t(s64, now - police->tcfp_t_c, p->tcfp_burst);
284 if (p->peak_present) {
285 ptoks = toks + police->tcfp_ptoks;
286 if (ptoks > p->tcfp_mtu_ptoks)
287 ptoks = p->tcfp_mtu_ptoks;
288 ptoks -= (s64)psched_l2t_ns(&p->peak,
289 qdisc_pkt_len(skb));
290 }
291 if (p->rate_present) {
292 toks += police->tcfp_toks;
293 if (toks > p->tcfp_burst)
294 toks = p->tcfp_burst;
295 toks -= (s64)psched_l2t_ns(&p->rate, qdisc_pkt_len(skb));
296 } else if (p->pps_present) {
297 ppstoks = min_t(s64, now - police->tcfp_t_c, p->tcfp_pkt_burst);
298 ppstoks += police->tcfp_pkttoks;
299 if (ppstoks > p->tcfp_pkt_burst)
300 ppstoks = p->tcfp_pkt_burst;
301 ppstoks -= (s64)psched_pkt2t_ns(&p->ppsrate, 1);
302 }
303 if ((toks | ptoks | ppstoks) >= 0) {
304 police->tcfp_t_c = now;
305 police->tcfp_toks = toks;
306 police->tcfp_ptoks = ptoks;
307 police->tcfp_pkttoks = ppstoks;
308 spin_unlock_bh(&police->tcfp_lock);
309 ret = p->tcfp_result;
310 goto inc_drops;
311 }
312 spin_unlock_bh(&police->tcfp_lock);
313 }
314
315 inc_overlimits:
316 qstats_cpu_overlimit_inc(police->common.cpu_qstats);
317 inc_drops:
318 if (ret == TC_ACT_SHOT)
319 qstats_cpu_drop_inc(police->common.cpu_qstats);
320 end:
321 return ret;
322 }
323
tcf_police_cleanup(struct tc_action * a)324 static void tcf_police_cleanup(struct tc_action *a)
325 {
326 struct tcf_police *police = to_police(a);
327 struct tcf_police_params *p;
328
329 p = rcu_dereference_protected(police->params, 1);
330 if (p)
331 kfree_rcu(p, rcu);
332 }
333
tcf_police_stats_update(struct tc_action * a,u64 bytes,u64 packets,u64 drops,u64 lastuse,bool hw)334 static void tcf_police_stats_update(struct tc_action *a,
335 u64 bytes, u64 packets, u64 drops,
336 u64 lastuse, bool hw)
337 {
338 struct tcf_police *police = to_police(a);
339 struct tcf_t *tm = &police->tcf_tm;
340
341 tcf_action_update_stats(a, bytes, packets, drops, hw);
342 tm->lastuse = max_t(u64, tm->lastuse, lastuse);
343 }
344
tcf_police_dump(struct sk_buff * skb,struct tc_action * a,int bind,int ref)345 static int tcf_police_dump(struct sk_buff *skb, struct tc_action *a,
346 int bind, int ref)
347 {
348 const struct tcf_police *police = to_police(a);
349 unsigned char *b = skb_tail_pointer(skb);
350 const struct tcf_police_params *p;
351 struct tc_police opt = {
352 .index = police->tcf_index,
353 .refcnt = refcount_read(&police->tcf_refcnt) - ref,
354 .bindcnt = atomic_read(&police->tcf_bindcnt) - bind,
355 };
356 struct tcf_t t;
357
358 rcu_read_lock();
359 p = rcu_dereference(police->params);
360 opt.action = p->action;
361 opt.mtu = p->tcfp_mtu;
362 opt.burst = PSCHED_NS2TICKS(p->tcfp_burst);
363 if (p->rate_present) {
364 psched_ratecfg_getrate(&opt.rate, &p->rate);
365 if ((p->rate.rate_bytes_ps >= (1ULL << 32)) &&
366 nla_put_u64_64bit(skb, TCA_POLICE_RATE64,
367 p->rate.rate_bytes_ps,
368 TCA_POLICE_PAD))
369 goto nla_put_failure;
370 }
371 if (p->peak_present) {
372 psched_ratecfg_getrate(&opt.peakrate, &p->peak);
373 if ((p->peak.rate_bytes_ps >= (1ULL << 32)) &&
374 nla_put_u64_64bit(skb, TCA_POLICE_PEAKRATE64,
375 p->peak.rate_bytes_ps,
376 TCA_POLICE_PAD))
377 goto nla_put_failure;
378 }
379 if (p->pps_present) {
380 if (nla_put_u64_64bit(skb, TCA_POLICE_PKTRATE64,
381 p->ppsrate.rate_pkts_ps,
382 TCA_POLICE_PAD))
383 goto nla_put_failure;
384 if (nla_put_u64_64bit(skb, TCA_POLICE_PKTBURST64,
385 PSCHED_NS2TICKS(p->tcfp_pkt_burst),
386 TCA_POLICE_PAD))
387 goto nla_put_failure;
388 }
389 if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt))
390 goto nla_put_failure;
391 if (p->tcfp_result &&
392 nla_put_u32(skb, TCA_POLICE_RESULT, p->tcfp_result))
393 goto nla_put_failure;
394 if (p->tcfp_ewma_rate &&
395 nla_put_u32(skb, TCA_POLICE_AVRATE, p->tcfp_ewma_rate))
396 goto nla_put_failure;
397
398 tcf_tm_dump(&t, &police->tcf_tm);
399 if (nla_put_64bit(skb, TCA_POLICE_TM, sizeof(t), &t, TCA_POLICE_PAD))
400 goto nla_put_failure;
401 rcu_read_unlock();
402
403 return skb->len;
404
405 nla_put_failure:
406 rcu_read_unlock();
407 nlmsg_trim(skb, b);
408 return -1;
409 }
410
tcf_police_act_to_flow_act(int tc_act,u32 * extval,struct netlink_ext_ack * extack)411 static int tcf_police_act_to_flow_act(int tc_act, u32 *extval,
412 struct netlink_ext_ack *extack)
413 {
414 int act_id = -EOPNOTSUPP;
415
416 if (!TC_ACT_EXT_OPCODE(tc_act)) {
417 if (tc_act == TC_ACT_OK)
418 act_id = FLOW_ACTION_ACCEPT;
419 else if (tc_act == TC_ACT_SHOT)
420 act_id = FLOW_ACTION_DROP;
421 else if (tc_act == TC_ACT_PIPE)
422 act_id = FLOW_ACTION_PIPE;
423 else if (tc_act == TC_ACT_RECLASSIFY)
424 NL_SET_ERR_MSG_MOD(extack, "Offload not supported when conform/exceed action is \"reclassify\"");
425 else
426 NL_SET_ERR_MSG_MOD(extack, "Unsupported conform/exceed action offload");
427 } else if (TC_ACT_EXT_CMP(tc_act, TC_ACT_GOTO_CHAIN)) {
428 act_id = FLOW_ACTION_GOTO;
429 *extval = tc_act & TC_ACT_EXT_VAL_MASK;
430 } else if (TC_ACT_EXT_CMP(tc_act, TC_ACT_JUMP)) {
431 act_id = FLOW_ACTION_JUMP;
432 *extval = tc_act & TC_ACT_EXT_VAL_MASK;
433 } else if (tc_act == TC_ACT_UNSPEC) {
434 act_id = FLOW_ACTION_CONTINUE;
435 } else {
436 NL_SET_ERR_MSG_MOD(extack, "Unsupported conform/exceed action offload");
437 }
438
439 return act_id;
440 }
441
tcf_police_offload_act_setup(struct tc_action * act,void * entry_data,u32 * index_inc,bool bind,struct netlink_ext_ack * extack)442 static int tcf_police_offload_act_setup(struct tc_action *act, void *entry_data,
443 u32 *index_inc, bool bind,
444 struct netlink_ext_ack *extack)
445 {
446 if (bind) {
447 struct flow_action_entry *entry = entry_data;
448 struct tcf_police *police = to_police(act);
449 struct tcf_police_params *p;
450 int act_id;
451
452 p = rcu_dereference_protected(police->params,
453 lockdep_is_held(&police->tcf_lock));
454
455 entry->id = FLOW_ACTION_POLICE;
456 entry->police.burst = tcf_police_burst(act);
457 entry->police.rate_bytes_ps =
458 tcf_police_rate_bytes_ps(act);
459 entry->police.peakrate_bytes_ps = tcf_police_peakrate_bytes_ps(act);
460 entry->police.avrate = tcf_police_tcfp_ewma_rate(act);
461 entry->police.overhead = tcf_police_rate_overhead(act);
462 entry->police.burst_pkt = tcf_police_burst_pkt(act);
463 entry->police.rate_pkt_ps =
464 tcf_police_rate_pkt_ps(act);
465 entry->police.mtu = tcf_police_tcfp_mtu(act);
466
467 act_id = tcf_police_act_to_flow_act(police->tcf_action,
468 &entry->police.exceed.extval,
469 extack);
470 if (act_id < 0)
471 return act_id;
472
473 entry->police.exceed.act_id = act_id;
474
475 act_id = tcf_police_act_to_flow_act(p->tcfp_result,
476 &entry->police.notexceed.extval,
477 extack);
478 if (act_id < 0)
479 return act_id;
480
481 entry->police.notexceed.act_id = act_id;
482
483 *index_inc = 1;
484 } else {
485 struct flow_offload_action *fl_action = entry_data;
486
487 fl_action->id = FLOW_ACTION_POLICE;
488 }
489
490 return 0;
491 }
492
tcf_police_get_fill_size(const struct tc_action * act)493 static size_t tcf_police_get_fill_size(const struct tc_action *act)
494 {
495 return nla_total_size(sizeof(struct tc_police)) /* TCA_POLICE_TBF */
496 + nla_total_size_64bit(sizeof(u64)) /* TCA_POLICE_RATE64 */
497 + nla_total_size_64bit(sizeof(u64)) /* TCA_POLICE_PEAKRATE64 */
498 + nla_total_size_64bit(sizeof(u64)) /* TCA_POLICE_PKTRATE64 */
499 + nla_total_size_64bit(sizeof(u64)) /* TCA_POLICE_PKTBURST64 */
500 + nla_total_size(sizeof(u32)) /* TCA_POLICE_RESULT */
501 + nla_total_size(sizeof(u32)); /* TCA_POLICE_AVRATE */
502 }
503
504 MODULE_AUTHOR("Alexey Kuznetsov");
505 MODULE_DESCRIPTION("Policing actions");
506 MODULE_LICENSE("GPL");
507
508 static struct tc_action_ops act_police_ops = {
509 .kind = "police",
510 .id = TCA_ID_POLICE,
511 .owner = THIS_MODULE,
512 .stats_update = tcf_police_stats_update,
513 .act = tcf_police_act,
514 .dump = tcf_police_dump,
515 .init = tcf_police_init,
516 .cleanup = tcf_police_cleanup,
517 .get_fill_size = tcf_police_get_fill_size,
518 .offload_act_setup = tcf_police_offload_act_setup,
519 .size = sizeof(struct tcf_police),
520 };
521 MODULE_ALIAS_NET_ACT("police");
522
police_init_net(struct net * net)523 static __net_init int police_init_net(struct net *net)
524 {
525 struct tc_action_net *tn = net_generic(net, act_police_ops.net_id);
526
527 return tc_action_net_init(net, tn, &act_police_ops);
528 }
529
police_exit_net(struct list_head * net_list)530 static void __net_exit police_exit_net(struct list_head *net_list)
531 {
532 tc_action_net_exit(net_list, act_police_ops.net_id);
533 }
534
535 static struct pernet_operations police_net_ops = {
536 .init = police_init_net,
537 .exit_batch = police_exit_net,
538 .id = &act_police_ops.net_id,
539 .size = sizeof(struct tc_action_net),
540 };
541
police_init_module(void)542 static int __init police_init_module(void)
543 {
544 return tcf_register_action(&act_police_ops, &police_net_ops);
545 }
546
police_cleanup_module(void)547 static void __exit police_cleanup_module(void)
548 {
549 tcf_unregister_action(&act_police_ops, &police_net_ops);
550 }
551
552 module_init(police_init_module);
553 module_exit(police_cleanup_module);
554