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 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 (TC_ACT_EXT_CMP(tcfp_result, TC_ACT_GOTO_CHAIN)) { 132 NL_SET_ERR_MSG(extack, 133 "goto chain not allowed on fallback"); 134 err = -EINVAL; 135 goto failure; 136 } 137 } 138 139 if ((tb[TCA_POLICE_PKTRATE64] && !tb[TCA_POLICE_PKTBURST64]) || 140 (!tb[TCA_POLICE_PKTRATE64] && tb[TCA_POLICE_PKTBURST64])) { 141 NL_SET_ERR_MSG(extack, 142 "Both or neither packet-per-second burst and rate must be provided"); 143 err = -EINVAL; 144 goto failure; 145 } 146 147 if (tb[TCA_POLICE_PKTRATE64] && R_tab) { 148 NL_SET_ERR_MSG(extack, 149 "packet-per-second and byte-per-second rate limits not allowed in same action"); 150 err = -EINVAL; 151 goto failure; 152 } 153 154 new = kzalloc(sizeof(*new), GFP_KERNEL); 155 if (unlikely(!new)) { 156 err = -ENOMEM; 157 goto failure; 158 } 159 160 /* No failure allowed after this point */ 161 new->tcfp_result = tcfp_result; 162 new->tcfp_mtu = parm->mtu; 163 if (!new->tcfp_mtu) { 164 new->tcfp_mtu = ~0; 165 if (R_tab) 166 new->tcfp_mtu = 255 << R_tab->rate.cell_log; 167 } 168 if (R_tab) { 169 new->rate_present = true; 170 rate64 = tb[TCA_POLICE_RATE64] ? 171 nla_get_u64(tb[TCA_POLICE_RATE64]) : 0; 172 psched_ratecfg_precompute(&new->rate, &R_tab->rate, rate64); 173 qdisc_put_rtab(R_tab); 174 } else { 175 new->rate_present = false; 176 } 177 if (P_tab) { 178 new->peak_present = true; 179 prate64 = tb[TCA_POLICE_PEAKRATE64] ? 180 nla_get_u64(tb[TCA_POLICE_PEAKRATE64]) : 0; 181 psched_ratecfg_precompute(&new->peak, &P_tab->rate, prate64); 182 qdisc_put_rtab(P_tab); 183 } else { 184 new->peak_present = false; 185 } 186 187 new->tcfp_burst = PSCHED_TICKS2NS(parm->burst); 188 if (new->peak_present) 189 new->tcfp_mtu_ptoks = (s64)psched_l2t_ns(&new->peak, 190 new->tcfp_mtu); 191 192 if (tb[TCA_POLICE_AVRATE]) 193 new->tcfp_ewma_rate = nla_get_u32(tb[TCA_POLICE_AVRATE]); 194 195 if (tb[TCA_POLICE_PKTRATE64]) { 196 pps = nla_get_u64(tb[TCA_POLICE_PKTRATE64]); 197 ppsburst = nla_get_u64(tb[TCA_POLICE_PKTBURST64]); 198 new->pps_present = true; 199 new->tcfp_pkt_burst = PSCHED_TICKS2NS(ppsburst); 200 psched_ppscfg_precompute(&new->ppsrate, pps); 201 } 202 203 spin_lock_bh(&police->tcf_lock); 204 spin_lock_bh(&police->tcfp_lock); 205 police->tcfp_t_c = ktime_get_ns(); 206 police->tcfp_toks = new->tcfp_burst; 207 if (new->peak_present) 208 police->tcfp_ptoks = new->tcfp_mtu_ptoks; 209 spin_unlock_bh(&police->tcfp_lock); 210 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 211 new = rcu_replace_pointer(police->params, 212 new, 213 lockdep_is_held(&police->tcf_lock)); 214 spin_unlock_bh(&police->tcf_lock); 215 216 if (goto_ch) 217 tcf_chain_put_by_act(goto_ch); 218 if (new) 219 kfree_rcu(new, rcu); 220 221 return ret; 222 223 failure: 224 qdisc_put_rtab(P_tab); 225 qdisc_put_rtab(R_tab); 226 if (goto_ch) 227 tcf_chain_put_by_act(goto_ch); 228 release_idr: 229 tcf_idr_release(*a, bind); 230 return err; 231 } 232 233 static bool tcf_police_mtu_check(struct sk_buff *skb, u32 limit) 234 { 235 u32 len; 236 237 if (skb_is_gso(skb)) 238 return skb_gso_validate_mac_len(skb, limit); 239 240 len = qdisc_pkt_len(skb); 241 if (skb_at_tc_ingress(skb)) 242 len += skb->mac_len; 243 244 return len <= limit; 245 } 246 247 TC_INDIRECT_SCOPE int tcf_police_act(struct sk_buff *skb, 248 const struct tc_action *a, 249 struct tcf_result *res) 250 { 251 struct tcf_police *police = to_police(a); 252 s64 now, toks, ppstoks = 0, ptoks = 0; 253 struct tcf_police_params *p; 254 int ret; 255 256 tcf_lastuse_update(&police->tcf_tm); 257 bstats_update(this_cpu_ptr(police->common.cpu_bstats), skb); 258 259 ret = READ_ONCE(police->tcf_action); 260 p = rcu_dereference_bh(police->params); 261 262 if (p->tcfp_ewma_rate) { 263 struct gnet_stats_rate_est64 sample; 264 265 if (!gen_estimator_read(&police->tcf_rate_est, &sample) || 266 sample.bps >= p->tcfp_ewma_rate) 267 goto inc_overlimits; 268 } 269 270 if (tcf_police_mtu_check(skb, p->tcfp_mtu)) { 271 if (!p->rate_present && !p->pps_present) { 272 ret = p->tcfp_result; 273 goto end; 274 } 275 276 now = ktime_get_ns(); 277 spin_lock_bh(&police->tcfp_lock); 278 toks = min_t(s64, now - police->tcfp_t_c, p->tcfp_burst); 279 if (p->peak_present) { 280 ptoks = toks + police->tcfp_ptoks; 281 if (ptoks > p->tcfp_mtu_ptoks) 282 ptoks = p->tcfp_mtu_ptoks; 283 ptoks -= (s64)psched_l2t_ns(&p->peak, 284 qdisc_pkt_len(skb)); 285 } 286 if (p->rate_present) { 287 toks += police->tcfp_toks; 288 if (toks > p->tcfp_burst) 289 toks = p->tcfp_burst; 290 toks -= (s64)psched_l2t_ns(&p->rate, qdisc_pkt_len(skb)); 291 } else if (p->pps_present) { 292 ppstoks = min_t(s64, now - police->tcfp_t_c, p->tcfp_pkt_burst); 293 ppstoks += police->tcfp_pkttoks; 294 if (ppstoks > p->tcfp_pkt_burst) 295 ppstoks = p->tcfp_pkt_burst; 296 ppstoks -= (s64)psched_pkt2t_ns(&p->ppsrate, 1); 297 } 298 if ((toks | ptoks | ppstoks) >= 0) { 299 police->tcfp_t_c = now; 300 police->tcfp_toks = toks; 301 police->tcfp_ptoks = ptoks; 302 police->tcfp_pkttoks = ppstoks; 303 spin_unlock_bh(&police->tcfp_lock); 304 ret = p->tcfp_result; 305 goto inc_drops; 306 } 307 spin_unlock_bh(&police->tcfp_lock); 308 } 309 310 inc_overlimits: 311 qstats_overlimit_inc(this_cpu_ptr(police->common.cpu_qstats)); 312 inc_drops: 313 if (ret == TC_ACT_SHOT) 314 qstats_drop_inc(this_cpu_ptr(police->common.cpu_qstats)); 315 end: 316 return ret; 317 } 318 319 static void tcf_police_cleanup(struct tc_action *a) 320 { 321 struct tcf_police *police = to_police(a); 322 struct tcf_police_params *p; 323 324 p = rcu_dereference_protected(police->params, 1); 325 if (p) 326 kfree_rcu(p, rcu); 327 } 328 329 static void tcf_police_stats_update(struct tc_action *a, 330 u64 bytes, u64 packets, u64 drops, 331 u64 lastuse, bool hw) 332 { 333 struct tcf_police *police = to_police(a); 334 struct tcf_t *tm = &police->tcf_tm; 335 336 tcf_action_update_stats(a, bytes, packets, drops, hw); 337 tm->lastuse = max_t(u64, tm->lastuse, lastuse); 338 } 339 340 static int tcf_police_dump(struct sk_buff *skb, struct tc_action *a, 341 int bind, int ref) 342 { 343 unsigned char *b = skb_tail_pointer(skb); 344 struct tcf_police *police = to_police(a); 345 struct tcf_police_params *p; 346 struct tc_police opt = { 347 .index = police->tcf_index, 348 .refcnt = refcount_read(&police->tcf_refcnt) - ref, 349 .bindcnt = atomic_read(&police->tcf_bindcnt) - bind, 350 }; 351 struct tcf_t t; 352 353 spin_lock_bh(&police->tcf_lock); 354 opt.action = police->tcf_action; 355 p = rcu_dereference_protected(police->params, 356 lockdep_is_held(&police->tcf_lock)); 357 opt.mtu = p->tcfp_mtu; 358 opt.burst = PSCHED_NS2TICKS(p->tcfp_burst); 359 if (p->rate_present) { 360 psched_ratecfg_getrate(&opt.rate, &p->rate); 361 if ((p->rate.rate_bytes_ps >= (1ULL << 32)) && 362 nla_put_u64_64bit(skb, TCA_POLICE_RATE64, 363 p->rate.rate_bytes_ps, 364 TCA_POLICE_PAD)) 365 goto nla_put_failure; 366 } 367 if (p->peak_present) { 368 psched_ratecfg_getrate(&opt.peakrate, &p->peak); 369 if ((p->peak.rate_bytes_ps >= (1ULL << 32)) && 370 nla_put_u64_64bit(skb, TCA_POLICE_PEAKRATE64, 371 p->peak.rate_bytes_ps, 372 TCA_POLICE_PAD)) 373 goto nla_put_failure; 374 } 375 if (p->pps_present) { 376 if (nla_put_u64_64bit(skb, TCA_POLICE_PKTRATE64, 377 p->ppsrate.rate_pkts_ps, 378 TCA_POLICE_PAD)) 379 goto nla_put_failure; 380 if (nla_put_u64_64bit(skb, TCA_POLICE_PKTBURST64, 381 PSCHED_NS2TICKS(p->tcfp_pkt_burst), 382 TCA_POLICE_PAD)) 383 goto nla_put_failure; 384 } 385 if (nla_put(skb, TCA_POLICE_TBF, sizeof(opt), &opt)) 386 goto nla_put_failure; 387 if (p->tcfp_result && 388 nla_put_u32(skb, TCA_POLICE_RESULT, p->tcfp_result)) 389 goto nla_put_failure; 390 if (p->tcfp_ewma_rate && 391 nla_put_u32(skb, TCA_POLICE_AVRATE, p->tcfp_ewma_rate)) 392 goto nla_put_failure; 393 394 tcf_tm_dump(&t, &police->tcf_tm); 395 if (nla_put_64bit(skb, TCA_POLICE_TM, sizeof(t), &t, TCA_POLICE_PAD)) 396 goto nla_put_failure; 397 spin_unlock_bh(&police->tcf_lock); 398 399 return skb->len; 400 401 nla_put_failure: 402 spin_unlock_bh(&police->tcf_lock); 403 nlmsg_trim(skb, b); 404 return -1; 405 } 406 407 static int tcf_police_act_to_flow_act(int tc_act, u32 *extval, 408 struct netlink_ext_ack *extack) 409 { 410 int act_id = -EOPNOTSUPP; 411 412 if (!TC_ACT_EXT_OPCODE(tc_act)) { 413 if (tc_act == TC_ACT_OK) 414 act_id = FLOW_ACTION_ACCEPT; 415 else if (tc_act == TC_ACT_SHOT) 416 act_id = FLOW_ACTION_DROP; 417 else if (tc_act == TC_ACT_PIPE) 418 act_id = FLOW_ACTION_PIPE; 419 else if (tc_act == TC_ACT_RECLASSIFY) 420 NL_SET_ERR_MSG_MOD(extack, "Offload not supported when conform/exceed action is \"reclassify\""); 421 else 422 NL_SET_ERR_MSG_MOD(extack, "Unsupported conform/exceed action offload"); 423 } else if (TC_ACT_EXT_CMP(tc_act, TC_ACT_GOTO_CHAIN)) { 424 act_id = FLOW_ACTION_GOTO; 425 *extval = tc_act & TC_ACT_EXT_VAL_MASK; 426 } else if (TC_ACT_EXT_CMP(tc_act, TC_ACT_JUMP)) { 427 act_id = FLOW_ACTION_JUMP; 428 *extval = tc_act & TC_ACT_EXT_VAL_MASK; 429 } else if (tc_act == TC_ACT_UNSPEC) { 430 act_id = FLOW_ACTION_CONTINUE; 431 } else { 432 NL_SET_ERR_MSG_MOD(extack, "Unsupported conform/exceed action offload"); 433 } 434 435 return act_id; 436 } 437 438 static int tcf_police_offload_act_setup(struct tc_action *act, void *entry_data, 439 u32 *index_inc, bool bind, 440 struct netlink_ext_ack *extack) 441 { 442 if (bind) { 443 struct flow_action_entry *entry = entry_data; 444 struct tcf_police *police = to_police(act); 445 struct tcf_police_params *p; 446 int act_id; 447 448 p = rcu_dereference_protected(police->params, 449 lockdep_is_held(&police->tcf_lock)); 450 451 entry->id = FLOW_ACTION_POLICE; 452 entry->police.burst = tcf_police_burst(act); 453 entry->police.rate_bytes_ps = 454 tcf_police_rate_bytes_ps(act); 455 entry->police.peakrate_bytes_ps = tcf_police_peakrate_bytes_ps(act); 456 entry->police.avrate = tcf_police_tcfp_ewma_rate(act); 457 entry->police.overhead = tcf_police_rate_overhead(act); 458 entry->police.burst_pkt = tcf_police_burst_pkt(act); 459 entry->police.rate_pkt_ps = 460 tcf_police_rate_pkt_ps(act); 461 entry->police.mtu = tcf_police_tcfp_mtu(act); 462 463 act_id = tcf_police_act_to_flow_act(police->tcf_action, 464 &entry->police.exceed.extval, 465 extack); 466 if (act_id < 0) 467 return act_id; 468 469 entry->police.exceed.act_id = act_id; 470 471 act_id = tcf_police_act_to_flow_act(p->tcfp_result, 472 &entry->police.notexceed.extval, 473 extack); 474 if (act_id < 0) 475 return act_id; 476 477 entry->police.notexceed.act_id = act_id; 478 479 *index_inc = 1; 480 } else { 481 struct flow_offload_action *fl_action = entry_data; 482 483 fl_action->id = FLOW_ACTION_POLICE; 484 } 485 486 return 0; 487 } 488 489 MODULE_AUTHOR("Alexey Kuznetsov"); 490 MODULE_DESCRIPTION("Policing actions"); 491 MODULE_LICENSE("GPL"); 492 493 static struct tc_action_ops act_police_ops = { 494 .kind = "police", 495 .id = TCA_ID_POLICE, 496 .owner = THIS_MODULE, 497 .stats_update = tcf_police_stats_update, 498 .act = tcf_police_act, 499 .dump = tcf_police_dump, 500 .init = tcf_police_init, 501 .cleanup = tcf_police_cleanup, 502 .offload_act_setup = tcf_police_offload_act_setup, 503 .size = sizeof(struct tcf_police), 504 }; 505 MODULE_ALIAS_NET_ACT("police"); 506 507 static __net_init int police_init_net(struct net *net) 508 { 509 struct tc_action_net *tn = net_generic(net, act_police_ops.net_id); 510 511 return tc_action_net_init(net, tn, &act_police_ops); 512 } 513 514 static void __net_exit police_exit_net(struct list_head *net_list) 515 { 516 tc_action_net_exit(net_list, act_police_ops.net_id); 517 } 518 519 static struct pernet_operations police_net_ops = { 520 .init = police_init_net, 521 .exit_batch = police_exit_net, 522 .id = &act_police_ops.net_id, 523 .size = sizeof(struct tc_action_net), 524 }; 525 526 static int __init police_init_module(void) 527 { 528 return tcf_register_action(&act_police_ops, &police_net_ops); 529 } 530 531 static void __exit police_cleanup_module(void) 532 { 533 tcf_unregister_action(&act_police_ops, &police_net_ops); 534 } 535 536 module_init(police_init_module); 537 module_exit(police_cleanup_module); 538