net/sched/act_api.c

   1 /*
   2  * net/sched/act_api.c  Packet action API.
   3  *
   4  *              This program is free software; you can redistribute it and/or
   5  *              modify it under the terms of the GNU General Public License
   6  *              as published by the Free Software Foundation; either version
   7  *              2 of the License, or (at your option) any later version.
   8  *
   9  * Author:      Jamal Hadi Salim
  10  *
  11  *
  12  */
  13
  14 #include <linux/types.h>
  15 #include <linux/kernel.h>
  16 #include <linux/string.h>
  17 #include <linux/errno.h>
  18 #include <linux/slab.h>
  19 #include <linux/skbuff.h>
  20 #include <linux/init.h>
  21 #include <linux/kmod.h>
  22 #include <linux/err.h>
  23 #include <linux/module.h>
  24 #include <linux/rhashtable.h>
  25 #include <linux/list.h>
  26 #include <net/net_namespace.h>
  27 #include <net/sock.h>
  28 #include <net/sch_generic.h>
  29 #include <net/pkt_cls.h>
  30 #include <net/act_api.h>
  31 #include <net/netlink.h>
  32
  33 static int tcf_action_goto_chain_init(struct tc_action *a, struct tcf_proto *tp)
  34 {
  35         u32 chain_index = a->tcfa_action & TC_ACT_EXT_VAL_MASK;
  36
  37         if (!tp)
  38                 return -EINVAL;
  39         a->goto_chain = tcf_chain_get_by_act(tp->chain->block, chain_index);
  40         if (!a->goto_chain)
  41                 return -ENOMEM;
  42         return 0;
  43 }
  44
  45 static void tcf_action_goto_chain_fini(struct tc_action *a)
  46 {
  47         tcf_chain_put_by_act(a->goto_chain);
  48 }
  49
  50 static void tcf_action_goto_chain_exec(const struct tc_action *a,
  51                                        struct tcf_result *res)
  52 {
  53         const struct tcf_chain *chain = a->goto_chain;
  54
  55         res->goto_tp = rcu_dereference_bh(chain->filter_chain);
  56 }
  57
  58 static void tcf_free_cookie_rcu(struct rcu_head *p)
  59 {
  60         struct tc_cookie *cookie = container_of(p, struct tc_cookie, rcu);
  61
  62         kfree(cookie->data);
  63         kfree(cookie);
  64 }
  65
  66 static void tcf_set_action_cookie(struct tc_cookie __rcu **old_cookie,
  67                                   struct tc_cookie *new_cookie)
  68 {
  69         struct tc_cookie *old;
  70
  71         old = xchg((__force struct tc_cookie **)old_cookie, new_cookie);
  72         if (old)
  73                 call_rcu(&old->rcu, tcf_free_cookie_rcu);
  74 }
  75
  76 /* XXX: For standalone actions, we don't need a RCU grace period either, because
  77  * actions are always connected to filters and filters are already destroyed in
  78  * RCU callbacks, so after a RCU grace period actions are already disconnected
  79  * from filters. Readers later can not find us.
  80  */
  81 static void free_tcf(struct tc_action *p)
  82 {
  83         free_percpu(p->cpu_bstats);
  84         free_percpu(p->cpu_qstats);
  85
  86         tcf_set_action_cookie(&p->act_cookie, NULL);
  87         if (p->goto_chain)
  88                 tcf_action_goto_chain_fini(p);
  89
  90         kfree(p);
  91 }
  92
  93 static void tcf_action_cleanup(struct tc_action *p)
  94 {
  95         if (p->ops->cleanup)
  96                 p->ops->cleanup(p);
  97
  98         gen_kill_estimator(&p->tcfa_rate_est);
  99         free_tcf(p);
 100 }
 101
 102 static int __tcf_action_put(struct tc_action *p, bool bind)
 103 {
 104         struct tcf_idrinfo *idrinfo = p->idrinfo;
 105
 106         if (refcount_dec_and_lock(&p->tcfa_refcnt, &idrinfo->lock)) {
 107                 if (bind)
 108                         atomic_dec(&p->tcfa_bindcnt);
 109                 idr_remove(&idrinfo->action_idr, p->tcfa_index);
 110                 spin_unlock(&idrinfo->lock);
 111
 112                 tcf_action_cleanup(p);
 113                 return 1;
 114         }
 115
 116         if (bind)
 117                 atomic_dec(&p->tcfa_bindcnt);
 118
 119         return 0;
 120 }
 121
 122 int __tcf_idr_release(struct tc_action *p, bool bind, bool strict)
 123 {
 124         int ret = 0;
 125
 126         /* Release with strict==1 and bind==0 is only called through act API
 127          * interface (classifiers always bind). Only case when action with
 128          * positive reference count and zero bind count can exist is when it was
 129          * also created with act API (unbinding last classifier will destroy the
 130          * action if it was created by classifier). So only case when bind count
 131          * can be changed after initial check is when unbound action is
 132          * destroyed by act API while classifier binds to action with same id
 133          * concurrently. This result either creation of new action(same behavior
 134          * as before), or reusing existing action if concurrent process
 135          * increments reference count before action is deleted. Both scenarios
 136          * are acceptable.
 137          */
 138         if (p) {
 139                 if (!bind && strict && atomic_read(&p->tcfa_bindcnt) > 0)
 140                         return -EPERM;
 141
 142                 if (__tcf_action_put(p, bind))
 143                         ret = ACT_P_DELETED;
 144         }
 145
 146         return ret;
 147 }
 148 EXPORT_SYMBOL(__tcf_idr_release);
 149
 150 static size_t tcf_action_shared_attrs_size(const struct tc_action *act)
 151 {
 152         struct tc_cookie *act_cookie;
 153         u32 cookie_len = 0;
 154
 155         rcu_read_lock();
 156         act_cookie = rcu_dereference(act->act_cookie);
 157
 158         if (act_cookie)
 159                 cookie_len = nla_total_size(act_cookie->len);
 160         rcu_read_unlock();
 161
 162         return  nla_total_size(0) /* action number nested */
 163                 + nla_total_size(IFNAMSIZ) /* TCA_ACT_KIND */
 164                 + cookie_len /* TCA_ACT_COOKIE */
 165                 + nla_total_size(0) /* TCA_ACT_STATS nested */
 166                 /* TCA_STATS_BASIC */
 167                 + nla_total_size_64bit(sizeof(struct gnet_stats_basic))
 168                 /* TCA_STATS_QUEUE */
 169                 + nla_total_size_64bit(sizeof(struct gnet_stats_queue))
 170                 + nla_total_size(0) /* TCA_OPTIONS nested */
 171                 + nla_total_size(sizeof(struct tcf_t)); /* TCA_GACT_TM */
 172 }
 173
 174 static size_t tcf_action_full_attrs_size(size_t sz)
 175 {
 176         return NLMSG_HDRLEN                     /* struct nlmsghdr */
 177                 + sizeof(struct tcamsg)
 178                 + nla_total_size(0)             /* TCA_ACT_TAB nested */
 179                 + sz;
 180 }
 181
 182 static size_t tcf_action_fill_size(const struct tc_action *act)
 183 {
 184         size_t sz = tcf_action_shared_attrs_size(act);
 185
 186         if (act->ops->get_fill_size)
 187                 return act->ops->get_fill_size(act) + sz;
 188         return sz;
 189 }
 190
 191 static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 192                            struct netlink_callback *cb)
 193 {
 194         int err = 0, index = -1, s_i = 0, n_i = 0;
 195         u32 act_flags = cb->args[2];
 196         unsigned long jiffy_since = cb->args[3];
 197         struct nlattr *nest;
 198         struct idr *idr = &idrinfo->action_idr;
 199         struct tc_action *p;
 200         unsigned long id = 1;
 201
 202         spin_lock(&idrinfo->lock);
 203
 204         s_i = cb->args[0];
 205
 206         idr_for_each_entry_ul(idr, p, id) {
 207                 index++;
 208                 if (index < s_i)
 209                         continue;
 210
 211                 if (jiffy_since &&
 212                     time_after(jiffy_since,
 213                                (unsigned long)p->tcfa_tm.lastuse))
 214                         continue;
 215
 216                 nest = nla_nest_start(skb, n_i);
 217                 if (!nest) {
 218                         index--;
 219                         goto nla_put_failure;
 220                 }
 221                 err = tcf_action_dump_1(skb, p, 0, 0);
 222                 if (err < 0) {
 223                         index--;
 224                         nlmsg_trim(skb, nest);
 225                         goto done;
 226                 }
 227                 nla_nest_end(skb, nest);
 228                 n_i++;
 229                 if (!(act_flags & TCA_FLAG_LARGE_DUMP_ON) &&
 230                     n_i >= TCA_ACT_MAX_PRIO)
 231                         goto done;
 232         }
 233 done:
 234         if (index >= 0)
 235                 cb->args[0] = index + 1;
 236
 237         spin_unlock(&idrinfo->lock);
 238         if (n_i) {
 239                 if (act_flags & TCA_FLAG_LARGE_DUMP_ON)
 240                         cb->args[1] = n_i;
 241         }
 242         return n_i;
 243
 244 nla_put_failure:
 245         nla_nest_cancel(skb, nest);
 246         goto done;
 247 }
 248
 249 static int tcf_del_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb,
 250                           const struct tc_action_ops *ops)
 251 {
 252         struct nlattr *nest;
 253         int n_i = 0;
 254         int ret = -EINVAL;
 255         struct idr *idr = &idrinfo->action_idr;
 256         struct tc_action *p;
 257         unsigned long id = 1;
 258
 259         nest = nla_nest_start(skb, 0);
 260         if (nest == NULL)
 261                 goto nla_put_failure;
 262         if (nla_put_string(skb, TCA_KIND, ops->kind))
 263                 goto nla_put_failure;
 264
 265         idr_for_each_entry_ul(idr, p, id) {
 266                 ret = __tcf_idr_release(p, false, true);
 267                 if (ret == ACT_P_DELETED) {
 268                         module_put(ops->owner);
 269                         n_i++;
 270                 } else if (ret < 0) {
 271                         goto nla_put_failure;
 272                 }
 273         }
 274         if (nla_put_u32(skb, TCA_FCNT, n_i))
 275                 goto nla_put_failure;
 276         nla_nest_end(skb, nest);
 277
 278         return n_i;
 279 nla_put_failure:
 280         nla_nest_cancel(skb, nest);
 281         return ret;
 282 }
 283
 284 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,
 285                        struct netlink_callback *cb, int type,
 286                        const struct tc_action_ops *ops,
 287                        struct netlink_ext_ack *extack)
 288 {
 289         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 290
 291         if (type == RTM_DELACTION) {
 292                 return tcf_del_walker(idrinfo, skb, ops);
 293         } else if (type == RTM_GETACTION) {
 294                 return tcf_dump_walker(idrinfo, skb, cb);
 295         } else {
 296                 WARN(1, "tcf_generic_walker: unknown command %d\n", type);
 297                 NL_SET_ERR_MSG(extack, "tcf_generic_walker: unknown command");
 298                 return -EINVAL;
 299         }
 300 }
 301 EXPORT_SYMBOL(tcf_generic_walker);
 302
 303 int tcf_idr_search(struct tc_action_net *tn, struct tc_action **a, u32 index)
 304 {
 305         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 306         struct tc_action *p;
 307
 308         spin_lock(&idrinfo->lock);
 309         p = idr_find(&idrinfo->action_idr, index);
 310         if (IS_ERR(p))
 311                 p = NULL;
 312         else if (p)
 313                 refcount_inc(&p->tcfa_refcnt);
 314         spin_unlock(&idrinfo->lock);
 315
 316         if (p) {
 317                 *a = p;
 318                 return true;
 319         }
 320         return false;
 321 }
 322 EXPORT_SYMBOL(tcf_idr_search);
 323
 324 static int tcf_idr_delete_index(struct tcf_idrinfo *idrinfo, u32 index)
 325 {
 326         struct tc_action *p;
 327         int ret = 0;
 328
 329         spin_lock(&idrinfo->lock);
 330         p = idr_find(&idrinfo->action_idr, index);
 331         if (!p) {
 332                 spin_unlock(&idrinfo->lock);
 333                 return -ENOENT;
 334         }
 335
 336         if (!atomic_read(&p->tcfa_bindcnt)) {
 337                 if (refcount_dec_and_test(&p->tcfa_refcnt)) {
 338                         struct module *owner = p->ops->owner;
 339
 340                         WARN_ON(p != idr_remove(&idrinfo->action_idr,
 341                                                 p->tcfa_index));
 342                         spin_unlock(&idrinfo->lock);
 343
 344                         tcf_action_cleanup(p);
 345                         module_put(owner);
 346                         return 0;
 347                 }
 348                 ret = 0;
 349         } else {
 350                 ret = -EPERM;
 351         }
 352
 353         spin_unlock(&idrinfo->lock);
 354         return ret;
 355 }
 356
 357 int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est,
 358                    struct tc_action **a, const struct tc_action_ops *ops,
 359                    int bind, bool cpustats)
 360 {
 361         struct tc_action *p = kzalloc(ops->size, GFP_KERNEL);
 362         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 363         int err = -ENOMEM;
 364
 365         if (unlikely(!p))
 366                 return -ENOMEM;
 367         refcount_set(&p->tcfa_refcnt, 1);
 368         if (bind)
 369                 atomic_set(&p->tcfa_bindcnt, 1);
 370
 371         if (cpustats) {
 372                 p->cpu_bstats = netdev_alloc_pcpu_stats(struct gnet_stats_basic_cpu);
 373                 if (!p->cpu_bstats)
 374                         goto err1;
 375                 p->cpu_qstats = alloc_percpu(struct gnet_stats_queue);
 376                 if (!p->cpu_qstats)
 377                         goto err2;
 378         }
 379         spin_lock_init(&p->tcfa_lock);
 380         p->tcfa_index = index;
 381         p->tcfa_tm.install = jiffies;
 382         p->tcfa_tm.lastuse = jiffies;
 383         p->tcfa_tm.firstuse = 0;
 384         if (est) {
 385                 err = gen_new_estimator(&p->tcfa_bstats, p->cpu_bstats,
 386                                         &p->tcfa_rate_est,
 387                                         &p->tcfa_lock, NULL, est);
 388                 if (err)
 389                         goto err3;
 390         }
 391
 392         p->idrinfo = idrinfo;
 393         p->ops = ops;
 394         *a = p;
 395         return 0;
 396 err3:
 397         free_percpu(p->cpu_qstats);
 398 err2:
 399         free_percpu(p->cpu_bstats);
 400 err1:
 401         kfree(p);
 402         return err;
 403 }
 404 EXPORT_SYMBOL(tcf_idr_create);
 405
 406 void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a)
 407 {
 408         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 409
 410         spin_lock(&idrinfo->lock);
 411         /* Replace ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 412         WARN_ON(!IS_ERR(idr_replace(&idrinfo->action_idr, a, a->tcfa_index)));
 413         spin_unlock(&idrinfo->lock);
 414 }
 415 EXPORT_SYMBOL(tcf_idr_insert);
 416
 417 /* Cleanup idr index that was allocated but not initialized. */
 418
 419 void tcf_idr_cleanup(struct tc_action_net *tn, u32 index)
 420 {
 421         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 422
 423         spin_lock(&idrinfo->lock);
 424         /* Remove ERR_PTR(-EBUSY) allocated by tcf_idr_check_alloc */
 425         WARN_ON(!IS_ERR(idr_remove(&idrinfo->action_idr, index)));
 426         spin_unlock(&idrinfo->lock);
 427 }
 428 EXPORT_SYMBOL(tcf_idr_cleanup);
 429
 430 /* Check if action with specified index exists. If actions is found, increments
 431  * its reference and bind counters, and return 1. Otherwise insert temporary
 432  * error pointer (to prevent concurrent users from inserting actions with same
 433  * index) and return 0.
 434  */
 435
 436 int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index,
 437                         struct tc_action **a, int bind)
 438 {
 439         struct tcf_idrinfo *idrinfo = tn->idrinfo;
 440         struct tc_action *p;
 441         int ret;
 442
 443 again:
 444         spin_lock(&idrinfo->lock);
 445         if (*index) {
 446                 p = idr_find(&idrinfo->action_idr, *index);
 447                 if (IS_ERR(p)) {
 448                         /* This means that another process allocated
 449                          * index but did not assign the pointer yet.
 450                          */
 451                         spin_unlock(&idrinfo->lock);
 452                         goto again;
 453                 }
 454
 455                 if (p) {
 456                         refcount_inc(&p->tcfa_refcnt);
 457                         if (bind)
 458                                 atomic_inc(&p->tcfa_bindcnt);
 459                         *a = p;
 460                         ret = 1;
 461                 } else {
 462                         *a = NULL;
 463                         ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 464                                             *index, GFP_ATOMIC);
 465                         if (!ret)
 466                                 idr_replace(&idrinfo->action_idr,
 467                                             ERR_PTR(-EBUSY), *index);
 468                 }
 469         } else {
 470                 *index = 1;
 471                 *a = NULL;
 472                 ret = idr_alloc_u32(&idrinfo->action_idr, NULL, index,
 473                                     UINT_MAX, GFP_ATOMIC);
 474                 if (!ret)
 475                         idr_replace(&idrinfo->action_idr, ERR_PTR(-EBUSY),
 476                                     *index);
 477         }
 478         spin_unlock(&idrinfo->lock);
 479         return ret;
 480 }
 481 EXPORT_SYMBOL(tcf_idr_check_alloc);
 482
 483 void tcf_idrinfo_destroy(const struct tc_action_ops *ops,
 484                          struct tcf_idrinfo *idrinfo)
 485 {
 486         struct idr *idr = &idrinfo->action_idr;
 487         struct tc_action *p;
 488         int ret;
 489         unsigned long id = 1;
 490
 491         idr_for_each_entry_ul(idr, p, id) {
 492                 ret = __tcf_idr_release(p, false, true);
 493                 if (ret == ACT_P_DELETED)
 494                         module_put(ops->owner);
 495                 else if (ret < 0)
 496                         return;
 497         }
 498         idr_destroy(&idrinfo->action_idr);
 499 }
 500 EXPORT_SYMBOL(tcf_idrinfo_destroy);
 501
 502 static LIST_HEAD(act_base);
 503 static DEFINE_RWLOCK(act_mod_lock);
 504
 505 int tcf_register_action(struct tc_action_ops *act,
 506                         struct pernet_operations *ops)
 507 {
 508         struct tc_action_ops *a;
 509         int ret;
 510
 511         if (!act->act || !act->dump || !act->init || !act->walk || !act->lookup)
 512                 return -EINVAL;
 513
 514         /* We have to register pernet ops before making the action ops visible,
 515          * otherwise tcf_action_init_1() could get a partially initialized
 516          * netns.
 517          */
 518         ret = register_pernet_subsys(ops);
 519         if (ret)
 520                 return ret;
 521
 522         write_lock(&act_mod_lock);
 523         list_for_each_entry(a, &act_base, head) {
 524                 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
 525                         write_unlock(&act_mod_lock);
 526                         unregister_pernet_subsys(ops);
 527                         return -EEXIST;
 528                 }
 529         }
 530         list_add_tail(&act->head, &act_base);
 531         write_unlock(&act_mod_lock);
 532
 533         return 0;
 534 }
 535 EXPORT_SYMBOL(tcf_register_action);
 536
 537 int tcf_unregister_action(struct tc_action_ops *act,
 538                           struct pernet_operations *ops)
 539 {
 540         struct tc_action_ops *a;
 541         int err = -ENOENT;
 542
 543         write_lock(&act_mod_lock);
 544         list_for_each_entry(a, &act_base, head) {
 545                 if (a == act) {
 546                         list_del(&act->head);
 547                         err = 0;
 548                         break;
 549                 }
 550         }
 551         write_unlock(&act_mod_lock);
 552         if (!err)
 553                 unregister_pernet_subsys(ops);
 554         return err;
 555 }
 556 EXPORT_SYMBOL(tcf_unregister_action);
 557
 558 /* lookup by name */
 559 static struct tc_action_ops *tc_lookup_action_n(char *kind)
 560 {
 561         struct tc_action_ops *a, *res = NULL;
 562
 563         if (kind) {
 564                 read_lock(&act_mod_lock);
 565                 list_for_each_entry(a, &act_base, head) {
 566                         if (strcmp(kind, a->kind) == 0) {
 567                                 if (try_module_get(a->owner))
 568                                         res = a;
 569                                 break;
 570                         }
 571                 }
 572                 read_unlock(&act_mod_lock);
 573         }
 574         return res;
 575 }
 576
 577 /* lookup by nlattr */
 578 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
 579 {
 580         struct tc_action_ops *a, *res = NULL;
 581
 582         if (kind) {
 583                 read_lock(&act_mod_lock);
 584                 list_for_each_entry(a, &act_base, head) {
 585                         if (nla_strcmp(kind, a->kind) == 0) {
 586                                 if (try_module_get(a->owner))
 587                                         res = a;
 588                                 break;
 589                         }
 590                 }
 591                 read_unlock(&act_mod_lock);
 592         }
 593         return res;
 594 }
 595
 596 /*TCA_ACT_MAX_PRIO is 32, there count upto 32 */
 597 #define TCA_ACT_MAX_PRIO_MASK 0x1FF
 598 int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions,
 599                     int nr_actions, struct tcf_result *res)
 600 {
 601         u32 jmp_prgcnt = 0;
 602         u32 jmp_ttl = TCA_ACT_MAX_PRIO; /*matches actions per filter */
 603         int i;
 604         int ret = TC_ACT_OK;
 605
 606         if (skb_skip_tc_classify(skb))
 607                 return TC_ACT_OK;
 608
 609 restart_act_graph:
 610         for (i = 0; i < nr_actions; i++) {
 611                 const struct tc_action *a = actions[i];
 612
 613                 if (jmp_prgcnt > 0) {
 614                         jmp_prgcnt -= 1;
 615                         continue;
 616                 }
 617 repeat:
 618                 ret = a->ops->act(skb, a, res);
 619                 if (ret == TC_ACT_REPEAT)
 620                         goto repeat;    /* we need a ttl - JHS */
 621
 622                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
 623                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
 624                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
 625                                 /* faulty opcode, stop pipeline */
 626                                 return TC_ACT_OK;
 627                         } else {
 628                                 jmp_ttl -= 1;
 629                                 if (jmp_ttl > 0)
 630                                         goto restart_act_graph;
 631                                 else /* faulty graph, stop pipeline */
 632                                         return TC_ACT_OK;
 633                         }
 634                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
 635                         tcf_action_goto_chain_exec(a, res);
 636                 }
 637
 638                 if (ret != TC_ACT_PIPE)
 639                         break;
 640         }
 641
 642         return ret;
 643 }
 644 EXPORT_SYMBOL(tcf_action_exec);
 645
 646 int tcf_action_destroy(struct tc_action *actions[], int bind)
 647 {
 648         const struct tc_action_ops *ops;
 649         struct tc_action *a;
 650         int ret = 0, i;
 651
 652         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 653                 a = actions[i];
 654                 actions[i] = NULL;
 655                 ops = a->ops;
 656                 ret = __tcf_idr_release(a, bind, true);
 657                 if (ret == ACT_P_DELETED)
 658                         module_put(ops->owner);
 659                 else if (ret < 0)
 660                         return ret;
 661         }
 662         return ret;
 663 }
 664
 665 static int tcf_action_put(struct tc_action *p)
 666 {
 667         return __tcf_action_put(p, false);
 668 }
 669
 670 /* Put all actions in this array, skip those NULL's. */
 671 static void tcf_action_put_many(struct tc_action *actions[])
 672 {
 673         int i;
 674
 675         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 676                 struct tc_action *a = actions[i];
 677                 const struct tc_action_ops *ops;
 678
 679                 if (!a)
 680                         continue;
 681                 ops = a->ops;
 682                 if (tcf_action_put(a))
 683                         module_put(ops->owner);
 684         }
 685 }
 686
 687 int
 688 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 689 {
 690         return a->ops->dump(skb, a, bind, ref);
 691 }
 692
 693 int
 694 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 695 {
 696         int err = -EINVAL;
 697         unsigned char *b = skb_tail_pointer(skb);
 698         struct nlattr *nest;
 699         struct tc_cookie *cookie;
 700
 701         if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 702                 goto nla_put_failure;
 703         if (tcf_action_copy_stats(skb, a, 0))
 704                 goto nla_put_failure;
 705
 706         rcu_read_lock();
 707         cookie = rcu_dereference(a->act_cookie);
 708         if (cookie) {
 709                 if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
 710                         rcu_read_unlock();
 711                         goto nla_put_failure;
 712                 }
 713         }
 714         rcu_read_unlock();
 715
 716         nest = nla_nest_start(skb, TCA_OPTIONS);
 717         if (nest == NULL)
 718                 goto nla_put_failure;
 719         err = tcf_action_dump_old(skb, a, bind, ref);
 720         if (err > 0) {
 721                 nla_nest_end(skb, nest);
 722                 return err;
 723         }
 724
 725 nla_put_failure:
 726         nlmsg_trim(skb, b);
 727         return -1;
 728 }
 729 EXPORT_SYMBOL(tcf_action_dump_1);
 730
 731 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
 732                     int bind, int ref)
 733 {
 734         struct tc_action *a;
 735         int err = -EINVAL, i;
 736         struct nlattr *nest;
 737
 738         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 739                 a = actions[i];
 740                 nest = nla_nest_start(skb, a->order);
 741                 if (nest == NULL)
 742                         goto nla_put_failure;
 743                 err = tcf_action_dump_1(skb, a, bind, ref);
 744                 if (err < 0)
 745                         goto errout;
 746                 nla_nest_end(skb, nest);
 747         }
 748
 749         return 0;
 750
 751 nla_put_failure:
 752         err = -EINVAL;
 753 errout:
 754         nla_nest_cancel(skb, nest);
 755         return err;
 756 }
 757
 758 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
 759 {
 760         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
 761         if (!c)
 762                 return NULL;
 763
 764         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
 765         if (!c->data) {
 766                 kfree(c);
 767                 return NULL;
 768         }
 769         c->len = nla_len(tb[TCA_ACT_COOKIE]);
 770
 771         return c;
 772 }
 773
 774 static bool tcf_action_valid(int action)
 775 {
 776         int opcode = TC_ACT_EXT_OPCODE(action);
 777
 778         if (!opcode)
 779                 return action <= TC_ACT_VALUE_MAX;
 780         return opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC;
 781 }
 782
 783 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 784                                     struct nlattr *nla, struct nlattr *est,
 785                                     char *name, int ovr, int bind,
 786                                     bool rtnl_held,
 787                                     struct netlink_ext_ack *extack)
 788 {
 789         struct tc_action *a;
 790         struct tc_action_ops *a_o;
 791         struct tc_cookie *cookie = NULL;
 792         char act_name[IFNAMSIZ];
 793         struct nlattr *tb[TCA_ACT_MAX + 1];
 794         struct nlattr *kind;
 795         int err;
 796
 797         if (name == NULL) {
 798                 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 799                 if (err < 0)
 800                         goto err_out;
 801                 err = -EINVAL;
 802                 kind = tb[TCA_ACT_KIND];
 803                 if (!kind) {
 804                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 805                         goto err_out;
 806                 }
 807                 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
 808                         NL_SET_ERR_MSG(extack, "TC action name too long");
 809                         goto err_out;
 810                 }
 811                 if (tb[TCA_ACT_COOKIE]) {
 812                         int cklen = nla_len(tb[TCA_ACT_COOKIE]);
 813
 814                         if (cklen > TC_COOKIE_MAX_SIZE) {
 815                                 NL_SET_ERR_MSG(extack, "TC cookie size above the maximum");
 816                                 goto err_out;
 817                         }
 818
 819                         cookie = nla_memdup_cookie(tb);
 820                         if (!cookie) {
 821                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
 822                                 err = -ENOMEM;
 823                                 goto err_out;
 824                         }
 825                 }
 826         } else {
 827                 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) {
 828                         NL_SET_ERR_MSG(extack, "TC action name too long");
 829                         err = -EINVAL;
 830                         goto err_out;
 831                 }
 832         }
 833
 834         a_o = tc_lookup_action_n(act_name);
 835         if (a_o == NULL) {
 836 #ifdef CONFIG_MODULES
 837                 if (rtnl_held)
 838                         rtnl_unlock();
 839                 request_module("act_%s", act_name);
 840                 if (rtnl_held)
 841                         rtnl_lock();
 842
 843                 a_o = tc_lookup_action_n(act_name);
 844
 845                 /* We dropped the RTNL semaphore in order to
 846                  * perform the module load.  So, even if we
 847                  * succeeded in loading the module we have to
 848                  * tell the caller to replay the request.  We
 849                  * indicate this using -EAGAIN.
 850                  */
 851                 if (a_o != NULL) {
 852                         err = -EAGAIN;
 853                         goto err_mod;
 854                 }
 855 #endif
 856                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
 857                 err = -ENOENT;
 858                 goto err_out;
 859         }
 860
 861         /* backward compatibility for policer */
 862         if (name == NULL)
 863                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind,
 864                                 rtnl_held, extack);
 865         else
 866                 err = a_o->init(net, nla, est, &a, ovr, bind, rtnl_held,
 867                                 extack);
 868         if (err < 0)
 869                 goto err_mod;
 870
 871         if (!name && tb[TCA_ACT_COOKIE])
 872                 tcf_set_action_cookie(&a->act_cookie, cookie);
 873
 874         /* module count goes up only when brand new policy is created
 875          * if it exists and is only bound to in a_o->init() then
 876          * ACT_P_CREATED is not returned (a zero is).
 877          */
 878         if (err != ACT_P_CREATED)
 879                 module_put(a_o->owner);
 880
 881         if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN)) {
 882                 err = tcf_action_goto_chain_init(a, tp);
 883                 if (err) {
 884                         struct tc_action *actions[] = { a, NULL };
 885
 886                         tcf_action_destroy(actions, bind);
 887                         NL_SET_ERR_MSG(extack, "Failed to init TC action chain");
 888                         return ERR_PTR(err);
 889                 }
 890         }
 891
 892         if (!tcf_action_valid(a->tcfa_action)) {
 893                 NL_SET_ERR_MSG(extack, "invalid action value, using TC_ACT_UNSPEC instead");
 894                 a->tcfa_action = TC_ACT_UNSPEC;
 895         }
 896
 897         return a;
 898
 899 err_mod:
 900         module_put(a_o->owner);
 901 err_out:
 902         if (cookie) {
 903                 kfree(cookie->data);
 904                 kfree(cookie);
 905         }
 906         return ERR_PTR(err);
 907 }
 908
 909 /* Returns numbers of initialized actions or negative error. */
 910
 911 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 912                     struct nlattr *est, char *name, int ovr, int bind,
 913                     struct tc_action *actions[], size_t *attr_size,
 914                     bool rtnl_held, struct netlink_ext_ack *extack)
 915 {
 916         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 917         struct tc_action *act;
 918         size_t sz = 0;
 919         int err;
 920         int i;
 921
 922         err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
 923         if (err < 0)
 924                 return err;
 925
 926         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 927                 act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind,
 928                                         rtnl_held, extack);
 929                 if (IS_ERR(act)) {
 930                         err = PTR_ERR(act);
 931                         goto err;
 932                 }
 933                 act->order = i;
 934                 sz += tcf_action_fill_size(act);
 935                 /* Start from index 0 */
 936                 actions[i - 1] = act;
 937         }
 938
 939         *attr_size = tcf_action_full_attrs_size(sz);
 940         return i - 1;
 941
 942 err:
 943         tcf_action_destroy(actions, bind);
 944         return err;
 945 }
 946
 947 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
 948                           int compat_mode)
 949 {
 950         int err = 0;
 951         struct gnet_dump d;
 952
 953         if (p == NULL)
 954                 goto errout;
 955
 956         /* compat_mode being true specifies a call that is supposed
 957          * to add additional backward compatibility statistic TLVs.
 958          */
 959         if (compat_mode) {
 960                 if (p->type == TCA_OLD_COMPAT)
 961                         err = gnet_stats_start_copy_compat(skb, 0,
 962                                                            TCA_STATS,
 963                                                            TCA_XSTATS,
 964                                                            &p->tcfa_lock, &d,
 965                                                            TCA_PAD);
 966                 else
 967                         return 0;
 968         } else
 969                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
 970                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
 971
 972         if (err < 0)
 973                 goto errout;
 974
 975         if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
 976             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
 977             gnet_stats_copy_queue(&d, p->cpu_qstats,
 978                                   &p->tcfa_qstats,
 979                                   p->tcfa_qstats.qlen) < 0)
 980                 goto errout;
 981
 982         if (gnet_stats_finish_copy(&d) < 0)
 983                 goto errout;
 984
 985         return 0;
 986
 987 errout:
 988         return -1;
 989 }
 990
 991 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
 992                         u32 portid, u32 seq, u16 flags, int event, int bind,
 993                         int ref)
 994 {
 995         struct tcamsg *t;
 996         struct nlmsghdr *nlh;
 997         unsigned char *b = skb_tail_pointer(skb);
 998         struct nlattr *nest;
 999
1000         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1001         if (!nlh)
1002                 goto out_nlmsg_trim;
1003         t = nlmsg_data(nlh);
1004         t->tca_family = AF_UNSPEC;
1005         t->tca__pad1 = 0;
1006         t->tca__pad2 = 0;
1007
1008         nest = nla_nest_start(skb, TCA_ACT_TAB);
1009         if (!nest)
1010                 goto out_nlmsg_trim;
1011
1012         if (tcf_action_dump(skb, actions, bind, ref) < 0)
1013                 goto out_nlmsg_trim;
1014
1015         nla_nest_end(skb, nest);
1016
1017         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1018         return skb->len;
1019
1020 out_nlmsg_trim:
1021         nlmsg_trim(skb, b);
1022         return -1;
1023 }
1024
1025 static int
1026 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1027                struct tc_action *actions[], int event,
1028                struct netlink_ext_ack *extack)
1029 {
1030         struct sk_buff *skb;
1031
1032         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1033         if (!skb)
1034                 return -ENOBUFS;
1035         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1036                          0, 1) <= 0) {
1037                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1038                 kfree_skb(skb);
1039                 return -EINVAL;
1040         }
1041
1042         return rtnl_unicast(skb, net, portid);
1043 }
1044
1045 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1046                                           struct nlmsghdr *n, u32 portid,
1047                                           struct netlink_ext_ack *extack)
1048 {
1049         struct nlattr *tb[TCA_ACT_MAX + 1];
1050         const struct tc_action_ops *ops;
1051         struct tc_action *a;
1052         int index;
1053         int err;
1054
1055         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
1056         if (err < 0)
1057                 goto err_out;
1058
1059         err = -EINVAL;
1060         if (tb[TCA_ACT_INDEX] == NULL ||
1061             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1062                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1063                 goto err_out;
1064         }
1065         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1066
1067         err = -EINVAL;
1068         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1069         if (!ops) { /* could happen in batch of actions */
1070                 NL_SET_ERR_MSG(extack, "Specified TC action not found");
1071                 goto err_out;
1072         }
1073         err = -ENOENT;
1074         if (ops->lookup(net, &a, index, extack) == 0)
1075                 goto err_mod;
1076
1077         module_put(ops->owner);
1078         return a;
1079
1080 err_mod:
1081         module_put(ops->owner);
1082 err_out:
1083         return ERR_PTR(err);
1084 }
1085
1086 static int tca_action_flush(struct net *net, struct nlattr *nla,
1087                             struct nlmsghdr *n, u32 portid,
1088                             struct netlink_ext_ack *extack)
1089 {
1090         struct sk_buff *skb;
1091         unsigned char *b;
1092         struct nlmsghdr *nlh;
1093         struct tcamsg *t;
1094         struct netlink_callback dcb;
1095         struct nlattr *nest;
1096         struct nlattr *tb[TCA_ACT_MAX + 1];
1097         const struct tc_action_ops *ops;
1098         struct nlattr *kind;
1099         int err = -ENOMEM;
1100
1101         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1102         if (!skb)
1103                 return err;
1104
1105         b = skb_tail_pointer(skb);
1106
1107         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
1108         if (err < 0)
1109                 goto err_out;
1110
1111         err = -EINVAL;
1112         kind = tb[TCA_ACT_KIND];
1113         ops = tc_lookup_action(kind);
1114         if (!ops) { /*some idjot trying to flush unknown action */
1115                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1116                 goto err_out;
1117         }
1118
1119         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1120                         sizeof(*t), 0);
1121         if (!nlh) {
1122                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1123                 goto out_module_put;
1124         }
1125         t = nlmsg_data(nlh);
1126         t->tca_family = AF_UNSPEC;
1127         t->tca__pad1 = 0;
1128         t->tca__pad2 = 0;
1129
1130         nest = nla_nest_start(skb, TCA_ACT_TAB);
1131         if (!nest) {
1132                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1133                 goto out_module_put;
1134         }
1135
1136         err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
1137         if (err <= 0) {
1138                 nla_nest_cancel(skb, nest);
1139                 goto out_module_put;
1140         }
1141
1142         nla_nest_end(skb, nest);
1143
1144         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1145         nlh->nlmsg_flags |= NLM_F_ROOT;
1146         module_put(ops->owner);
1147         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1148                              n->nlmsg_flags & NLM_F_ECHO);
1149         if (err > 0)
1150                 return 0;
1151         if (err < 0)
1152                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1153
1154         return err;
1155
1156 out_module_put:
1157         module_put(ops->owner);
1158 err_out:
1159         kfree_skb(skb);
1160         return err;
1161 }
1162
1163 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1164 {
1165         int i;
1166
1167         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1168                 struct tc_action *a = actions[i];
1169                 const struct tc_action_ops *ops = a->ops;
1170                 /* Actions can be deleted concurrently so we must save their
1171                  * type and id to search again after reference is released.
1172                  */
1173                 struct tcf_idrinfo *idrinfo = a->idrinfo;
1174                 u32 act_index = a->tcfa_index;
1175
1176                 if (tcf_action_put(a)) {
1177                         /* last reference, action was deleted concurrently */
1178                         module_put(ops->owner);
1179                 } else  {
1180                         int ret;
1181
1182                         /* now do the delete */
1183                         ret = tcf_idr_delete_index(idrinfo, act_index);
1184                         if (ret < 0)
1185                                 return ret;
1186                 }
1187                 actions[i] = NULL;
1188         }
1189         return 0;
1190 }
1191
1192 static int
1193 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1194                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1195 {
1196         int ret;
1197         struct sk_buff *skb;
1198
1199         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1200                         GFP_KERNEL);
1201         if (!skb)
1202                 return -ENOBUFS;
1203
1204         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1205                          0, 2) <= 0) {
1206                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1207                 kfree_skb(skb);
1208                 return -EINVAL;
1209         }
1210
1211         /* now do the delete */
1212         ret = tcf_action_delete(net, actions);
1213         if (ret < 0) {
1214                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1215                 kfree_skb(skb);
1216                 return ret;
1217         }
1218
1219         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1220                              n->nlmsg_flags & NLM_F_ECHO);
1221         if (ret > 0)
1222                 return 0;
1223         return ret;
1224 }
1225
1226 static int
1227 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1228               u32 portid, int event, struct netlink_ext_ack *extack)
1229 {
1230         int i, ret;
1231         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1232         struct tc_action *act;
1233         size_t attr_size = 0;
1234         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1235
1236         ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
1237         if (ret < 0)
1238                 return ret;
1239
1240         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1241                 if (tb[1])
1242                         return tca_action_flush(net, tb[1], n, portid, extack);
1243
1244                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1245                 return -EINVAL;
1246         }
1247
1248         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1249                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1250                 if (IS_ERR(act)) {
1251                         ret = PTR_ERR(act);
1252                         goto err;
1253                 }
1254                 act->order = i;
1255                 attr_size += tcf_action_fill_size(act);
1256                 actions[i - 1] = act;
1257         }
1258
1259         attr_size = tcf_action_full_attrs_size(attr_size);
1260
1261         if (event == RTM_GETACTION)
1262                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
1263         else { /* delete */
1264                 ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1265                 if (ret)
1266                         goto err;
1267                 return 0;
1268         }
1269 err:
1270         tcf_action_put_many(actions);
1271         return ret;
1272 }
1273
1274 static int
1275 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1276                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1277 {
1278         struct sk_buff *skb;
1279         int err = 0;
1280
1281         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1282                         GFP_KERNEL);
1283         if (!skb)
1284                 return -ENOBUFS;
1285
1286         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1287                          RTM_NEWACTION, 0, 0) <= 0) {
1288                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1289                 kfree_skb(skb);
1290                 return -EINVAL;
1291         }
1292
1293         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1294                              n->nlmsg_flags & NLM_F_ECHO);
1295         if (err > 0)
1296                 err = 0;
1297         return err;
1298 }
1299
1300 static int tcf_action_add(struct net *net, struct nlattr *nla,
1301                           struct nlmsghdr *n, u32 portid, int ovr,
1302                           struct netlink_ext_ack *extack)
1303 {
1304         size_t attr_size = 0;
1305         int ret = 0;
1306         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1307
1308         ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0, actions,
1309                               &attr_size, true, extack);
1310         if (ret < 0)
1311                 return ret;
1312         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1313         if (ovr)
1314                 tcf_action_put_many(actions);
1315
1316         return ret;
1317 }
1318
1319 static u32 tcaa_root_flags_allowed = TCA_FLAG_LARGE_DUMP_ON;
1320 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
1321         [TCA_ROOT_FLAGS] = { .type = NLA_BITFIELD32,
1322                              .validation_data = &tcaa_root_flags_allowed },
1323         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
1324 };
1325
1326 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
1327                          struct netlink_ext_ack *extack)
1328 {
1329         struct net *net = sock_net(skb->sk);
1330         struct nlattr *tca[TCA_ROOT_MAX + 1];
1331         u32 portid = skb ? NETLINK_CB(skb).portid : 0;
1332         int ret = 0, ovr = 0;
1333
1334         if ((n->nlmsg_type != RTM_GETACTION) &&
1335             !netlink_capable(skb, CAP_NET_ADMIN))
1336                 return -EPERM;
1337
1338         ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ROOT_MAX, NULL,
1339                           extack);
1340         if (ret < 0)
1341                 return ret;
1342
1343         if (tca[TCA_ACT_TAB] == NULL) {
1344                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
1345                 return -EINVAL;
1346         }
1347
1348         /* n->nlmsg_flags & NLM_F_CREATE */
1349         switch (n->nlmsg_type) {
1350         case RTM_NEWACTION:
1351                 /* we are going to assume all other flags
1352                  * imply create only if it doesn't exist
1353                  * Note that CREATE | EXCL implies that
1354                  * but since we want avoid ambiguity (eg when flags
1355                  * is zero) then just set this
1356                  */
1357                 if (n->nlmsg_flags & NLM_F_REPLACE)
1358                         ovr = 1;
1359 replay:
1360                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr,
1361                                      extack);
1362                 if (ret == -EAGAIN)
1363                         goto replay;
1364                 break;
1365         case RTM_DELACTION:
1366                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1367                                     portid, RTM_DELACTION, extack);
1368                 break;
1369         case RTM_GETACTION:
1370                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1371                                     portid, RTM_GETACTION, extack);
1372                 break;
1373         default:
1374                 BUG();
1375         }
1376
1377         return ret;
1378 }
1379
1380 static struct nlattr *find_dump_kind(struct nlattr **nla)
1381 {
1382         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1383         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1384         struct nlattr *kind;
1385
1386         tb1 = nla[TCA_ACT_TAB];
1387         if (tb1 == NULL)
1388                 return NULL;
1389
1390         if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1391                       NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
1392                 return NULL;
1393
1394         if (tb[1] == NULL)
1395                 return NULL;
1396         if (nla_parse_nested(tb2, TCA_ACT_MAX, tb[1], NULL, NULL) < 0)
1397                 return NULL;
1398         kind = tb2[TCA_ACT_KIND];
1399
1400         return kind;
1401 }
1402
1403 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1404 {
1405         struct net *net = sock_net(skb->sk);
1406         struct nlmsghdr *nlh;
1407         unsigned char *b = skb_tail_pointer(skb);
1408         struct nlattr *nest;
1409         struct tc_action_ops *a_o;
1410         int ret = 0;
1411         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1412         struct nlattr *tb[TCA_ROOT_MAX + 1];
1413         struct nlattr *count_attr = NULL;
1414         unsigned long jiffy_since = 0;
1415         struct nlattr *kind = NULL;
1416         struct nla_bitfield32 bf;
1417         u32 msecs_since = 0;
1418         u32 act_count = 0;
1419
1420         ret = nlmsg_parse(cb->nlh, sizeof(struct tcamsg), tb, TCA_ROOT_MAX,
1421                           tcaa_policy, NULL);
1422         if (ret < 0)
1423                 return ret;
1424
1425         kind = find_dump_kind(tb);
1426         if (kind == NULL) {
1427                 pr_info("tc_dump_action: action bad kind\n");
1428                 return 0;
1429         }
1430
1431         a_o = tc_lookup_action(kind);
1432         if (a_o == NULL)
1433                 return 0;
1434
1435         cb->args[2] = 0;
1436         if (tb[TCA_ROOT_FLAGS]) {
1437                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
1438                 cb->args[2] = bf.value;
1439         }
1440
1441         if (tb[TCA_ROOT_TIME_DELTA]) {
1442                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
1443         }
1444
1445         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1446                         cb->nlh->nlmsg_type, sizeof(*t), 0);
1447         if (!nlh)
1448                 goto out_module_put;
1449
1450         if (msecs_since)
1451                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
1452
1453         t = nlmsg_data(nlh);
1454         t->tca_family = AF_UNSPEC;
1455         t->tca__pad1 = 0;
1456         t->tca__pad2 = 0;
1457         cb->args[3] = jiffy_since;
1458         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
1459         if (!count_attr)
1460                 goto out_module_put;
1461
1462         nest = nla_nest_start(skb, TCA_ACT_TAB);
1463         if (nest == NULL)
1464                 goto out_module_put;
1465
1466         ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
1467         if (ret < 0)
1468                 goto out_module_put;
1469
1470         if (ret > 0) {
1471                 nla_nest_end(skb, nest);
1472                 ret = skb->len;
1473                 act_count = cb->args[1];
1474                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
1475                 cb->args[1] = 0;
1476         } else
1477                 nlmsg_trim(skb, b);
1478
1479         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1480         if (NETLINK_CB(cb->skb).portid && ret)
1481                 nlh->nlmsg_flags |= NLM_F_MULTI;
1482         module_put(a_o->owner);
1483         return skb->len;
1484
1485 out_module_put:
1486         module_put(a_o->owner);
1487         nlmsg_trim(skb, b);
1488         return skb->len;
1489 }
1490
1491 struct tcf_action_net {
1492         struct rhashtable egdev_ht;
1493 };
1494
1495 static unsigned int tcf_action_net_id;
1496
1497 struct tcf_action_egdev_cb {
1498         struct list_head list;
1499         tc_setup_cb_t *cb;
1500         void *cb_priv;
1501 };
1502
1503 struct tcf_action_egdev {
1504         struct rhash_head ht_node;
1505         const struct net_device *dev;
1506         unsigned int refcnt;
1507         struct list_head cb_list;
1508 };
1509
1510 static const struct rhashtable_params tcf_action_egdev_ht_params = {
1511         .key_offset = offsetof(struct tcf_action_egdev, dev),
1512         .head_offset = offsetof(struct tcf_action_egdev, ht_node),
1513         .key_len = sizeof(const struct net_device *),
1514 };
1515
1516 static struct tcf_action_egdev *
1517 tcf_action_egdev_lookup(const struct net_device *dev)
1518 {
1519         struct net *net = dev_net(dev);
1520         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1521
1522         return rhashtable_lookup_fast(&tan->egdev_ht, &dev,
1523                                       tcf_action_egdev_ht_params);
1524 }
1525
1526 static struct tcf_action_egdev *
1527 tcf_action_egdev_get(const struct net_device *dev)
1528 {
1529         struct tcf_action_egdev *egdev;
1530         struct tcf_action_net *tan;
1531
1532         egdev = tcf_action_egdev_lookup(dev);
1533         if (egdev)
1534                 goto inc_ref;
1535
1536         egdev = kzalloc(sizeof(*egdev), GFP_KERNEL);
1537         if (!egdev)
1538                 return NULL;
1539         INIT_LIST_HEAD(&egdev->cb_list);
1540         egdev->dev = dev;
1541         tan = net_generic(dev_net(dev), tcf_action_net_id);
1542         rhashtable_insert_fast(&tan->egdev_ht, &egdev->ht_node,
1543                                tcf_action_egdev_ht_params);
1544
1545 inc_ref:
1546         egdev->refcnt++;
1547         return egdev;
1548 }
1549
1550 static void tcf_action_egdev_put(struct tcf_action_egdev *egdev)
1551 {
1552         struct tcf_action_net *tan;
1553
1554         if (--egdev->refcnt)
1555                 return;
1556         tan = net_generic(dev_net(egdev->dev), tcf_action_net_id);
1557         rhashtable_remove_fast(&tan->egdev_ht, &egdev->ht_node,
1558                                tcf_action_egdev_ht_params);
1559         kfree(egdev);
1560 }
1561
1562 static struct tcf_action_egdev_cb *
1563 tcf_action_egdev_cb_lookup(struct tcf_action_egdev *egdev,
1564                            tc_setup_cb_t *cb, void *cb_priv)
1565 {
1566         struct tcf_action_egdev_cb *egdev_cb;
1567
1568         list_for_each_entry(egdev_cb, &egdev->cb_list, list)
1569                 if (egdev_cb->cb == cb && egdev_cb->cb_priv == cb_priv)
1570                         return egdev_cb;
1571         return NULL;
1572 }
1573
1574 static int tcf_action_egdev_cb_call(struct tcf_action_egdev *egdev,
1575                                     enum tc_setup_type type,
1576                                     void *type_data, bool err_stop)
1577 {
1578         struct tcf_action_egdev_cb *egdev_cb;
1579         int ok_count = 0;
1580         int err;
1581
1582         list_for_each_entry(egdev_cb, &egdev->cb_list, list) {
1583                 err = egdev_cb->cb(type, type_data, egdev_cb->cb_priv);
1584                 if (err) {
1585                         if (err_stop)
1586                                 return err;
1587                 } else {
1588                         ok_count++;
1589                 }
1590         }
1591         return ok_count;
1592 }
1593
1594 static int tcf_action_egdev_cb_add(struct tcf_action_egdev *egdev,
1595                                    tc_setup_cb_t *cb, void *cb_priv)
1596 {
1597         struct tcf_action_egdev_cb *egdev_cb;
1598
1599         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1600         if (WARN_ON(egdev_cb))
1601                 return -EEXIST;
1602         egdev_cb = kzalloc(sizeof(*egdev_cb), GFP_KERNEL);
1603         if (!egdev_cb)
1604                 return -ENOMEM;
1605         egdev_cb->cb = cb;
1606         egdev_cb->cb_priv = cb_priv;
1607         list_add(&egdev_cb->list, &egdev->cb_list);
1608         return 0;
1609 }
1610
1611 static void tcf_action_egdev_cb_del(struct tcf_action_egdev *egdev,
1612                                     tc_setup_cb_t *cb, void *cb_priv)
1613 {
1614         struct tcf_action_egdev_cb *egdev_cb;
1615
1616         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1617         if (WARN_ON(!egdev_cb))
1618                 return;
1619         list_del(&egdev_cb->list);
1620         kfree(egdev_cb);
1621 }
1622
1623 static int __tc_setup_cb_egdev_register(const struct net_device *dev,
1624                                         tc_setup_cb_t *cb, void *cb_priv)
1625 {
1626         struct tcf_action_egdev *egdev = tcf_action_egdev_get(dev);
1627         int err;
1628
1629         if (!egdev)
1630                 return -ENOMEM;
1631         err = tcf_action_egdev_cb_add(egdev, cb, cb_priv);
1632         if (err)
1633                 goto err_cb_add;
1634         return 0;
1635
1636 err_cb_add:
1637         tcf_action_egdev_put(egdev);
1638         return err;
1639 }
1640 int tc_setup_cb_egdev_register(const struct net_device *dev,
1641                                tc_setup_cb_t *cb, void *cb_priv)
1642 {
1643         int err;
1644
1645         rtnl_lock();
1646         err = __tc_setup_cb_egdev_register(dev, cb, cb_priv);
1647         rtnl_unlock();
1648         return err;
1649 }
1650 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_register);
1651
1652 static void __tc_setup_cb_egdev_unregister(const struct net_device *dev,
1653                                            tc_setup_cb_t *cb, void *cb_priv)
1654 {
1655         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1656
1657         if (WARN_ON(!egdev))
1658                 return;
1659         tcf_action_egdev_cb_del(egdev, cb, cb_priv);
1660         tcf_action_egdev_put(egdev);
1661 }
1662 void tc_setup_cb_egdev_unregister(const struct net_device *dev,
1663                                   tc_setup_cb_t *cb, void *cb_priv)
1664 {
1665         rtnl_lock();
1666         __tc_setup_cb_egdev_unregister(dev, cb, cb_priv);
1667         rtnl_unlock();
1668 }
1669 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_unregister);
1670
1671 int tc_setup_cb_egdev_call(const struct net_device *dev,
1672                            enum tc_setup_type type, void *type_data,
1673                            bool err_stop)
1674 {
1675         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1676
1677         if (!egdev)
1678                 return 0;
1679         return tcf_action_egdev_cb_call(egdev, type, type_data, err_stop);
1680 }
1681 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_call);
1682
1683 static __net_init int tcf_action_net_init(struct net *net)
1684 {
1685         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1686
1687         return rhashtable_init(&tan->egdev_ht, &tcf_action_egdev_ht_params);
1688 }
1689
1690 static void __net_exit tcf_action_net_exit(struct net *net)
1691 {
1692         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1693
1694         rhashtable_destroy(&tan->egdev_ht);
1695 }
1696
1697 static struct pernet_operations tcf_action_net_ops = {
1698         .init = tcf_action_net_init,
1699         .exit = tcf_action_net_exit,
1700         .id = &tcf_action_net_id,
1701         .size = sizeof(struct tcf_action_net),
1702 };
1703
1704 static int __init tc_action_init(void)
1705 {
1706         int err;
1707
1708         err = register_pernet_subsys(&tcf_action_net_ops);
1709         if (err)
1710                 return err;
1711
1712         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
1713         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
1714         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1715                       0);
1716
1717         return 0;
1718 }
1719
1720 subsys_initcall(tc_action_init);