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                 int repeat_ttl;
 613
 614                 if (jmp_prgcnt > 0) {
 615                         jmp_prgcnt -= 1;
 616                         continue;
 617                 }
 618
 619                 repeat_ttl = 32;
 620 repeat:
 621                 ret = a->ops->act(skb, a, res);
 622
 623                 if (unlikely(ret == TC_ACT_REPEAT)) {
 624                         if (--repeat_ttl != 0)
 625                                 goto repeat;
 626                         /* suspicious opcode, stop pipeline */
 627                         net_warn_ratelimited("TC_ACT_REPEAT abuse ?\n");
 628                         return TC_ACT_OK;
 629                 }
 630
 631                 if (TC_ACT_EXT_CMP(ret, TC_ACT_JUMP)) {
 632                         jmp_prgcnt = ret & TCA_ACT_MAX_PRIO_MASK;
 633                         if (!jmp_prgcnt || (jmp_prgcnt > nr_actions)) {
 634                                 /* faulty opcode, stop pipeline */
 635                                 return TC_ACT_OK;
 636                         } else {
 637                                 jmp_ttl -= 1;
 638                                 if (jmp_ttl > 0)
 639                                         goto restart_act_graph;
 640                                 else /* faulty graph, stop pipeline */
 641                                         return TC_ACT_OK;
 642                         }
 643                 } else if (TC_ACT_EXT_CMP(ret, TC_ACT_GOTO_CHAIN)) {
 644                         tcf_action_goto_chain_exec(a, res);
 645                 }
 646
 647                 if (ret != TC_ACT_PIPE)
 648                         break;
 649         }
 650
 651         return ret;
 652 }
 653 EXPORT_SYMBOL(tcf_action_exec);
 654
 655 int tcf_action_destroy(struct tc_action *actions[], int bind)
 656 {
 657         const struct tc_action_ops *ops;
 658         struct tc_action *a;
 659         int ret = 0, i;
 660
 661         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 662                 a = actions[i];
 663                 actions[i] = NULL;
 664                 ops = a->ops;
 665                 ret = __tcf_idr_release(a, bind, true);
 666                 if (ret == ACT_P_DELETED)
 667                         module_put(ops->owner);
 668                 else if (ret < 0)
 669                         return ret;
 670         }
 671         return ret;
 672 }
 673
 674 static int tcf_action_destroy_1(struct tc_action *a, int bind)
 675 {
 676         struct tc_action *actions[] = { a, NULL };
 677
 678         return tcf_action_destroy(actions, bind);
 679 }
 680
 681 static int tcf_action_put(struct tc_action *p)
 682 {
 683         return __tcf_action_put(p, false);
 684 }
 685
 686 /* Put all actions in this array, skip those NULL's. */
 687 static void tcf_action_put_many(struct tc_action *actions[])
 688 {
 689         int i;
 690
 691         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 692                 struct tc_action *a = actions[i];
 693                 const struct tc_action_ops *ops;
 694
 695                 if (!a)
 696                         continue;
 697                 ops = a->ops;
 698                 if (tcf_action_put(a))
 699                         module_put(ops->owner);
 700         }
 701 }
 702
 703 int
 704 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 705 {
 706         return a->ops->dump(skb, a, bind, ref);
 707 }
 708
 709 int
 710 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 711 {
 712         int err = -EINVAL;
 713         unsigned char *b = skb_tail_pointer(skb);
 714         struct nlattr *nest;
 715         struct tc_cookie *cookie;
 716
 717         if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 718                 goto nla_put_failure;
 719         if (tcf_action_copy_stats(skb, a, 0))
 720                 goto nla_put_failure;
 721
 722         rcu_read_lock();
 723         cookie = rcu_dereference(a->act_cookie);
 724         if (cookie) {
 725                 if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
 726                         rcu_read_unlock();
 727                         goto nla_put_failure;
 728                 }
 729         }
 730         rcu_read_unlock();
 731
 732         nest = nla_nest_start(skb, TCA_OPTIONS);
 733         if (nest == NULL)
 734                 goto nla_put_failure;
 735         err = tcf_action_dump_old(skb, a, bind, ref);
 736         if (err > 0) {
 737                 nla_nest_end(skb, nest);
 738                 return err;
 739         }
 740
 741 nla_put_failure:
 742         nlmsg_trim(skb, b);
 743         return -1;
 744 }
 745 EXPORT_SYMBOL(tcf_action_dump_1);
 746
 747 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
 748                     int bind, int ref)
 749 {
 750         struct tc_action *a;
 751         int err = -EINVAL, i;
 752         struct nlattr *nest;
 753
 754         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 755                 a = actions[i];
 756                 nest = nla_nest_start(skb, i + 1);
 757                 if (nest == NULL)
 758                         goto nla_put_failure;
 759                 err = tcf_action_dump_1(skb, a, bind, ref);
 760                 if (err < 0)
 761                         goto errout;
 762                 nla_nest_end(skb, nest);
 763         }
 764
 765         return 0;
 766
 767 nla_put_failure:
 768         err = -EINVAL;
 769 errout:
 770         nla_nest_cancel(skb, nest);
 771         return err;
 772 }
 773
 774 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
 775 {
 776         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
 777         if (!c)
 778                 return NULL;
 779
 780         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
 781         if (!c->data) {
 782                 kfree(c);
 783                 return NULL;
 784         }
 785         c->len = nla_len(tb[TCA_ACT_COOKIE]);
 786
 787         return c;
 788 }
 789
 790 static bool tcf_action_valid(int action)
 791 {
 792         int opcode = TC_ACT_EXT_OPCODE(action);
 793
 794         if (!opcode)
 795                 return action <= TC_ACT_VALUE_MAX;
 796         return opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC;
 797 }
 798
 799 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 800                                     struct nlattr *nla, struct nlattr *est,
 801                                     char *name, int ovr, int bind,
 802                                     bool rtnl_held,
 803                                     struct netlink_ext_ack *extack)
 804 {
 805         struct tc_action *a;
 806         struct tc_action_ops *a_o;
 807         struct tc_cookie *cookie = NULL;
 808         char act_name[IFNAMSIZ];
 809         struct nlattr *tb[TCA_ACT_MAX + 1];
 810         struct nlattr *kind;
 811         int err;
 812
 813         if (name == NULL) {
 814                 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 815                 if (err < 0)
 816                         goto err_out;
 817                 err = -EINVAL;
 818                 kind = tb[TCA_ACT_KIND];
 819                 if (!kind) {
 820                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 821                         goto err_out;
 822                 }
 823                 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
 824                         NL_SET_ERR_MSG(extack, "TC action name too long");
 825                         goto err_out;
 826                 }
 827                 if (tb[TCA_ACT_COOKIE]) {
 828                         int cklen = nla_len(tb[TCA_ACT_COOKIE]);
 829
 830                         if (cklen > TC_COOKIE_MAX_SIZE) {
 831                                 NL_SET_ERR_MSG(extack, "TC cookie size above the maximum");
 832                                 goto err_out;
 833                         }
 834
 835                         cookie = nla_memdup_cookie(tb);
 836                         if (!cookie) {
 837                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
 838                                 err = -ENOMEM;
 839                                 goto err_out;
 840                         }
 841                 }
 842         } else {
 843                 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) {
 844                         NL_SET_ERR_MSG(extack, "TC action name too long");
 845                         err = -EINVAL;
 846                         goto err_out;
 847                 }
 848         }
 849
 850         a_o = tc_lookup_action_n(act_name);
 851         if (a_o == NULL) {
 852 #ifdef CONFIG_MODULES
 853                 if (rtnl_held)
 854                         rtnl_unlock();
 855                 request_module("act_%s", act_name);
 856                 if (rtnl_held)
 857                         rtnl_lock();
 858
 859                 a_o = tc_lookup_action_n(act_name);
 860
 861                 /* We dropped the RTNL semaphore in order to
 862                  * perform the module load.  So, even if we
 863                  * succeeded in loading the module we have to
 864                  * tell the caller to replay the request.  We
 865                  * indicate this using -EAGAIN.
 866                  */
 867                 if (a_o != NULL) {
 868                         err = -EAGAIN;
 869                         goto err_mod;
 870                 }
 871 #endif
 872                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
 873                 err = -ENOENT;
 874                 goto err_out;
 875         }
 876
 877         /* backward compatibility for policer */
 878         if (name == NULL)
 879                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind,
 880                                 rtnl_held, extack);
 881         else
 882                 err = a_o->init(net, nla, est, &a, ovr, bind, rtnl_held,
 883                                 extack);
 884         if (err < 0)
 885                 goto err_mod;
 886
 887         if (!name && tb[TCA_ACT_COOKIE])
 888                 tcf_set_action_cookie(&a->act_cookie, cookie);
 889
 890         /* module count goes up only when brand new policy is created
 891          * if it exists and is only bound to in a_o->init() then
 892          * ACT_P_CREATED is not returned (a zero is).
 893          */
 894         if (err != ACT_P_CREATED)
 895                 module_put(a_o->owner);
 896
 897         if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN)) {
 898                 err = tcf_action_goto_chain_init(a, tp);
 899                 if (err) {
 900                         tcf_action_destroy_1(a, bind);
 901                         NL_SET_ERR_MSG(extack, "Failed to init TC action chain");
 902                         return ERR_PTR(err);
 903                 }
 904         }
 905
 906         if (!tcf_action_valid(a->tcfa_action)) {
 907                 tcf_action_destroy_1(a, bind);
 908                 NL_SET_ERR_MSG(extack, "Invalid control action value");
 909                 return ERR_PTR(-EINVAL);
 910         }
 911
 912         if (!bind && ovr && err == ACT_P_CREATED)
 913                 refcount_set(&a->tcfa_refcnt, 2);
 914
 915         return a;
 916
 917 err_mod:
 918         module_put(a_o->owner);
 919 err_out:
 920         if (cookie) {
 921                 kfree(cookie->data);
 922                 kfree(cookie);
 923         }
 924         return ERR_PTR(err);
 925 }
 926
 927 /* Returns numbers of initialized actions or negative error. */
 928
 929 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 930                     struct nlattr *est, char *name, int ovr, int bind,
 931                     struct tc_action *actions[], size_t *attr_size,
 932                     bool rtnl_held, struct netlink_ext_ack *extack)
 933 {
 934         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 935         struct tc_action *act;
 936         size_t sz = 0;
 937         int err;
 938         int i;
 939
 940         err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
 941         if (err < 0)
 942                 return err;
 943
 944         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 945                 act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind,
 946                                         rtnl_held, extack);
 947                 if (IS_ERR(act)) {
 948                         err = PTR_ERR(act);
 949                         goto err;
 950                 }
 951                 act->order = i;
 952                 sz += tcf_action_fill_size(act);
 953                 /* Start from index 0 */
 954                 actions[i - 1] = act;
 955         }
 956
 957         *attr_size = tcf_action_full_attrs_size(sz);
 958         return i - 1;
 959
 960 err:
 961         tcf_action_destroy(actions, bind);
 962         return err;
 963 }
 964
 965 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
 966                           int compat_mode)
 967 {
 968         int err = 0;
 969         struct gnet_dump d;
 970
 971         if (p == NULL)
 972                 goto errout;
 973
 974         /* compat_mode being true specifies a call that is supposed
 975          * to add additional backward compatibility statistic TLVs.
 976          */
 977         if (compat_mode) {
 978                 if (p->type == TCA_OLD_COMPAT)
 979                         err = gnet_stats_start_copy_compat(skb, 0,
 980                                                            TCA_STATS,
 981                                                            TCA_XSTATS,
 982                                                            &p->tcfa_lock, &d,
 983                                                            TCA_PAD);
 984                 else
 985                         return 0;
 986         } else
 987                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
 988                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
 989
 990         if (err < 0)
 991                 goto errout;
 992
 993         if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
 994             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
 995             gnet_stats_copy_queue(&d, p->cpu_qstats,
 996                                   &p->tcfa_qstats,
 997                                   p->tcfa_qstats.qlen) < 0)
 998                 goto errout;
 999
1000         if (gnet_stats_finish_copy(&d) < 0)
1001                 goto errout;
1002
1003         return 0;
1004
1005 errout:
1006         return -1;
1007 }
1008
1009 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1010                         u32 portid, u32 seq, u16 flags, int event, int bind,
1011                         int ref)
1012 {
1013         struct tcamsg *t;
1014         struct nlmsghdr *nlh;
1015         unsigned char *b = skb_tail_pointer(skb);
1016         struct nlattr *nest;
1017
1018         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1019         if (!nlh)
1020                 goto out_nlmsg_trim;
1021         t = nlmsg_data(nlh);
1022         t->tca_family = AF_UNSPEC;
1023         t->tca__pad1 = 0;
1024         t->tca__pad2 = 0;
1025
1026         nest = nla_nest_start(skb, TCA_ACT_TAB);
1027         if (!nest)
1028                 goto out_nlmsg_trim;
1029
1030         if (tcf_action_dump(skb, actions, bind, ref) < 0)
1031                 goto out_nlmsg_trim;
1032
1033         nla_nest_end(skb, nest);
1034
1035         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1036         return skb->len;
1037
1038 out_nlmsg_trim:
1039         nlmsg_trim(skb, b);
1040         return -1;
1041 }
1042
1043 static int
1044 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1045                struct tc_action *actions[], int event,
1046                struct netlink_ext_ack *extack)
1047 {
1048         struct sk_buff *skb;
1049
1050         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1051         if (!skb)
1052                 return -ENOBUFS;
1053         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1054                          0, 1) <= 0) {
1055                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1056                 kfree_skb(skb);
1057                 return -EINVAL;
1058         }
1059
1060         return rtnl_unicast(skb, net, portid);
1061 }
1062
1063 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1064                                           struct nlmsghdr *n, u32 portid,
1065                                           struct netlink_ext_ack *extack)
1066 {
1067         struct nlattr *tb[TCA_ACT_MAX + 1];
1068         const struct tc_action_ops *ops;
1069         struct tc_action *a;
1070         int index;
1071         int err;
1072
1073         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
1074         if (err < 0)
1075                 goto err_out;
1076
1077         err = -EINVAL;
1078         if (tb[TCA_ACT_INDEX] == NULL ||
1079             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1080                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1081                 goto err_out;
1082         }
1083         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1084
1085         err = -EINVAL;
1086         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1087         if (!ops) { /* could happen in batch of actions */
1088                 NL_SET_ERR_MSG(extack, "Specified TC action not found");
1089                 goto err_out;
1090         }
1091         err = -ENOENT;
1092         if (ops->lookup(net, &a, index, extack) == 0)
1093                 goto err_mod;
1094
1095         module_put(ops->owner);
1096         return a;
1097
1098 err_mod:
1099         module_put(ops->owner);
1100 err_out:
1101         return ERR_PTR(err);
1102 }
1103
1104 static int tca_action_flush(struct net *net, struct nlattr *nla,
1105                             struct nlmsghdr *n, u32 portid,
1106                             struct netlink_ext_ack *extack)
1107 {
1108         struct sk_buff *skb;
1109         unsigned char *b;
1110         struct nlmsghdr *nlh;
1111         struct tcamsg *t;
1112         struct netlink_callback dcb;
1113         struct nlattr *nest;
1114         struct nlattr *tb[TCA_ACT_MAX + 1];
1115         const struct tc_action_ops *ops;
1116         struct nlattr *kind;
1117         int err = -ENOMEM;
1118
1119         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1120         if (!skb)
1121                 return err;
1122
1123         b = skb_tail_pointer(skb);
1124
1125         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
1126         if (err < 0)
1127                 goto err_out;
1128
1129         err = -EINVAL;
1130         kind = tb[TCA_ACT_KIND];
1131         ops = tc_lookup_action(kind);
1132         if (!ops) { /*some idjot trying to flush unknown action */
1133                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1134                 goto err_out;
1135         }
1136
1137         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1138                         sizeof(*t), 0);
1139         if (!nlh) {
1140                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1141                 goto out_module_put;
1142         }
1143         t = nlmsg_data(nlh);
1144         t->tca_family = AF_UNSPEC;
1145         t->tca__pad1 = 0;
1146         t->tca__pad2 = 0;
1147
1148         nest = nla_nest_start(skb, TCA_ACT_TAB);
1149         if (!nest) {
1150                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1151                 goto out_module_put;
1152         }
1153
1154         err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
1155         if (err <= 0) {
1156                 nla_nest_cancel(skb, nest);
1157                 goto out_module_put;
1158         }
1159
1160         nla_nest_end(skb, nest);
1161
1162         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1163         nlh->nlmsg_flags |= NLM_F_ROOT;
1164         module_put(ops->owner);
1165         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1166                              n->nlmsg_flags & NLM_F_ECHO);
1167         if (err > 0)
1168                 return 0;
1169         if (err < 0)
1170                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1171
1172         return err;
1173
1174 out_module_put:
1175         module_put(ops->owner);
1176 err_out:
1177         kfree_skb(skb);
1178         return err;
1179 }
1180
1181 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1182 {
1183         int i;
1184
1185         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1186                 struct tc_action *a = actions[i];
1187                 const struct tc_action_ops *ops = a->ops;
1188                 /* Actions can be deleted concurrently so we must save their
1189                  * type and id to search again after reference is released.
1190                  */
1191                 struct tcf_idrinfo *idrinfo = a->idrinfo;
1192                 u32 act_index = a->tcfa_index;
1193
1194                 actions[i] = NULL;
1195                 if (tcf_action_put(a)) {
1196                         /* last reference, action was deleted concurrently */
1197                         module_put(ops->owner);
1198                 } else  {
1199                         int ret;
1200
1201                         /* now do the delete */
1202                         ret = tcf_idr_delete_index(idrinfo, act_index);
1203                         if (ret < 0)
1204                                 return ret;
1205                 }
1206         }
1207         return 0;
1208 }
1209
1210 static int
1211 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1212                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1213 {
1214         int ret;
1215         struct sk_buff *skb;
1216
1217         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1218                         GFP_KERNEL);
1219         if (!skb)
1220                 return -ENOBUFS;
1221
1222         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1223                          0, 2) <= 0) {
1224                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1225                 kfree_skb(skb);
1226                 return -EINVAL;
1227         }
1228
1229         /* now do the delete */
1230         ret = tcf_action_delete(net, actions);
1231         if (ret < 0) {
1232                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1233                 kfree_skb(skb);
1234                 return ret;
1235         }
1236
1237         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1238                              n->nlmsg_flags & NLM_F_ECHO);
1239         if (ret > 0)
1240                 return 0;
1241         return ret;
1242 }
1243
1244 static int
1245 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1246               u32 portid, int event, struct netlink_ext_ack *extack)
1247 {
1248         int i, ret;
1249         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1250         struct tc_action *act;
1251         size_t attr_size = 0;
1252         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1253
1254         ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
1255         if (ret < 0)
1256                 return ret;
1257
1258         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1259                 if (tb[1])
1260                         return tca_action_flush(net, tb[1], n, portid, extack);
1261
1262                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1263                 return -EINVAL;
1264         }
1265
1266         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1267                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1268                 if (IS_ERR(act)) {
1269                         ret = PTR_ERR(act);
1270                         goto err;
1271                 }
1272                 attr_size += tcf_action_fill_size(act);
1273                 actions[i - 1] = act;
1274         }
1275
1276         attr_size = tcf_action_full_attrs_size(attr_size);
1277
1278         if (event == RTM_GETACTION)
1279                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
1280         else { /* delete */
1281                 ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1282                 if (ret)
1283                         goto err;
1284                 return 0;
1285         }
1286 err:
1287         tcf_action_put_many(actions);
1288         return ret;
1289 }
1290
1291 static int
1292 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1293                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1294 {
1295         struct sk_buff *skb;
1296         int err = 0;
1297
1298         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1299                         GFP_KERNEL);
1300         if (!skb)
1301                 return -ENOBUFS;
1302
1303         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1304                          RTM_NEWACTION, 0, 0) <= 0) {
1305                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1306                 kfree_skb(skb);
1307                 return -EINVAL;
1308         }
1309
1310         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1311                              n->nlmsg_flags & NLM_F_ECHO);
1312         if (err > 0)
1313                 err = 0;
1314         return err;
1315 }
1316
1317 static int tcf_action_add(struct net *net, struct nlattr *nla,
1318                           struct nlmsghdr *n, u32 portid, int ovr,
1319                           struct netlink_ext_ack *extack)
1320 {
1321         size_t attr_size = 0;
1322         int loop, ret;
1323         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1324
1325         for (loop = 0; loop < 10; loop++) {
1326                 ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0,
1327                                       actions, &attr_size, true, extack);
1328                 if (ret != -EAGAIN)
1329                         break;
1330         }
1331
1332         if (ret < 0)
1333                 return ret;
1334         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1335         if (ovr)
1336                 tcf_action_put_many(actions);
1337
1338         return ret;
1339 }
1340
1341 static u32 tcaa_root_flags_allowed = TCA_FLAG_LARGE_DUMP_ON;
1342 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
1343         [TCA_ROOT_FLAGS] = { .type = NLA_BITFIELD32,
1344                              .validation_data = &tcaa_root_flags_allowed },
1345         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
1346 };
1347
1348 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
1349                          struct netlink_ext_ack *extack)
1350 {
1351         struct net *net = sock_net(skb->sk);
1352         struct nlattr *tca[TCA_ROOT_MAX + 1];
1353         u32 portid = skb ? NETLINK_CB(skb).portid : 0;
1354         int ret = 0, ovr = 0;
1355
1356         if ((n->nlmsg_type != RTM_GETACTION) &&
1357             !netlink_capable(skb, CAP_NET_ADMIN))
1358                 return -EPERM;
1359
1360         ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ROOT_MAX, NULL,
1361                           extack);
1362         if (ret < 0)
1363                 return ret;
1364
1365         if (tca[TCA_ACT_TAB] == NULL) {
1366                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
1367                 return -EINVAL;
1368         }
1369
1370         /* n->nlmsg_flags & NLM_F_CREATE */
1371         switch (n->nlmsg_type) {
1372         case RTM_NEWACTION:
1373                 /* we are going to assume all other flags
1374                  * imply create only if it doesn't exist
1375                  * Note that CREATE | EXCL implies that
1376                  * but since we want avoid ambiguity (eg when flags
1377                  * is zero) then just set this
1378                  */
1379                 if (n->nlmsg_flags & NLM_F_REPLACE)
1380                         ovr = 1;
1381                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr,
1382                                      extack);
1383                 break;
1384         case RTM_DELACTION:
1385                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1386                                     portid, RTM_DELACTION, extack);
1387                 break;
1388         case RTM_GETACTION:
1389                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1390                                     portid, RTM_GETACTION, extack);
1391                 break;
1392         default:
1393                 BUG();
1394         }
1395
1396         return ret;
1397 }
1398
1399 static struct nlattr *find_dump_kind(struct nlattr **nla)
1400 {
1401         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1402         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1403         struct nlattr *kind;
1404
1405         tb1 = nla[TCA_ACT_TAB];
1406         if (tb1 == NULL)
1407                 return NULL;
1408
1409         if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1410                       NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
1411                 return NULL;
1412
1413         if (tb[1] == NULL)
1414                 return NULL;
1415         if (nla_parse_nested(tb2, TCA_ACT_MAX, tb[1], NULL, NULL) < 0)
1416                 return NULL;
1417         kind = tb2[TCA_ACT_KIND];
1418
1419         return kind;
1420 }
1421
1422 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1423 {
1424         struct net *net = sock_net(skb->sk);
1425         struct nlmsghdr *nlh;
1426         unsigned char *b = skb_tail_pointer(skb);
1427         struct nlattr *nest;
1428         struct tc_action_ops *a_o;
1429         int ret = 0;
1430         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1431         struct nlattr *tb[TCA_ROOT_MAX + 1];
1432         struct nlattr *count_attr = NULL;
1433         unsigned long jiffy_since = 0;
1434         struct nlattr *kind = NULL;
1435         struct nla_bitfield32 bf;
1436         u32 msecs_since = 0;
1437         u32 act_count = 0;
1438
1439         ret = nlmsg_parse(cb->nlh, sizeof(struct tcamsg), tb, TCA_ROOT_MAX,
1440                           tcaa_policy, NULL);
1441         if (ret < 0)
1442                 return ret;
1443
1444         kind = find_dump_kind(tb);
1445         if (kind == NULL) {
1446                 pr_info("tc_dump_action: action bad kind\n");
1447                 return 0;
1448         }
1449
1450         a_o = tc_lookup_action(kind);
1451         if (a_o == NULL)
1452                 return 0;
1453
1454         cb->args[2] = 0;
1455         if (tb[TCA_ROOT_FLAGS]) {
1456                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
1457                 cb->args[2] = bf.value;
1458         }
1459
1460         if (tb[TCA_ROOT_TIME_DELTA]) {
1461                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
1462         }
1463
1464         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1465                         cb->nlh->nlmsg_type, sizeof(*t), 0);
1466         if (!nlh)
1467                 goto out_module_put;
1468
1469         if (msecs_since)
1470                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
1471
1472         t = nlmsg_data(nlh);
1473         t->tca_family = AF_UNSPEC;
1474         t->tca__pad1 = 0;
1475         t->tca__pad2 = 0;
1476         cb->args[3] = jiffy_since;
1477         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
1478         if (!count_attr)
1479                 goto out_module_put;
1480
1481         nest = nla_nest_start(skb, TCA_ACT_TAB);
1482         if (nest == NULL)
1483                 goto out_module_put;
1484
1485         ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
1486         if (ret < 0)
1487                 goto out_module_put;
1488
1489         if (ret > 0) {
1490                 nla_nest_end(skb, nest);
1491                 ret = skb->len;
1492                 act_count = cb->args[1];
1493                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
1494                 cb->args[1] = 0;
1495         } else
1496                 nlmsg_trim(skb, b);
1497
1498         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1499         if (NETLINK_CB(cb->skb).portid && ret)
1500                 nlh->nlmsg_flags |= NLM_F_MULTI;
1501         module_put(a_o->owner);
1502         return skb->len;
1503
1504 out_module_put:
1505         module_put(a_o->owner);
1506         nlmsg_trim(skb, b);
1507         return skb->len;
1508 }
1509
1510 struct tcf_action_net {
1511         struct rhashtable egdev_ht;
1512 };
1513
1514 static unsigned int tcf_action_net_id;
1515
1516 struct tcf_action_egdev_cb {
1517         struct list_head list;
1518         tc_setup_cb_t *cb;
1519         void *cb_priv;
1520 };
1521
1522 struct tcf_action_egdev {
1523         struct rhash_head ht_node;
1524         const struct net_device *dev;
1525         unsigned int refcnt;
1526         struct list_head cb_list;
1527 };
1528
1529 static const struct rhashtable_params tcf_action_egdev_ht_params = {
1530         .key_offset = offsetof(struct tcf_action_egdev, dev),
1531         .head_offset = offsetof(struct tcf_action_egdev, ht_node),
1532         .key_len = sizeof(const struct net_device *),
1533 };
1534
1535 static struct tcf_action_egdev *
1536 tcf_action_egdev_lookup(const struct net_device *dev)
1537 {
1538         struct net *net = dev_net(dev);
1539         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1540
1541         return rhashtable_lookup_fast(&tan->egdev_ht, &dev,
1542                                       tcf_action_egdev_ht_params);
1543 }
1544
1545 static struct tcf_action_egdev *
1546 tcf_action_egdev_get(const struct net_device *dev)
1547 {
1548         struct tcf_action_egdev *egdev;
1549         struct tcf_action_net *tan;
1550
1551         egdev = tcf_action_egdev_lookup(dev);
1552         if (egdev)
1553                 goto inc_ref;
1554
1555         egdev = kzalloc(sizeof(*egdev), GFP_KERNEL);
1556         if (!egdev)
1557                 return NULL;
1558         INIT_LIST_HEAD(&egdev->cb_list);
1559         egdev->dev = dev;
1560         tan = net_generic(dev_net(dev), tcf_action_net_id);
1561         rhashtable_insert_fast(&tan->egdev_ht, &egdev->ht_node,
1562                                tcf_action_egdev_ht_params);
1563
1564 inc_ref:
1565         egdev->refcnt++;
1566         return egdev;
1567 }
1568
1569 static void tcf_action_egdev_put(struct tcf_action_egdev *egdev)
1570 {
1571         struct tcf_action_net *tan;
1572
1573         if (--egdev->refcnt)
1574                 return;
1575         tan = net_generic(dev_net(egdev->dev), tcf_action_net_id);
1576         rhashtable_remove_fast(&tan->egdev_ht, &egdev->ht_node,
1577                                tcf_action_egdev_ht_params);
1578         kfree(egdev);
1579 }
1580
1581 static struct tcf_action_egdev_cb *
1582 tcf_action_egdev_cb_lookup(struct tcf_action_egdev *egdev,
1583                            tc_setup_cb_t *cb, void *cb_priv)
1584 {
1585         struct tcf_action_egdev_cb *egdev_cb;
1586
1587         list_for_each_entry(egdev_cb, &egdev->cb_list, list)
1588                 if (egdev_cb->cb == cb && egdev_cb->cb_priv == cb_priv)
1589                         return egdev_cb;
1590         return NULL;
1591 }
1592
1593 static int tcf_action_egdev_cb_call(struct tcf_action_egdev *egdev,
1594                                     enum tc_setup_type type,
1595                                     void *type_data, bool err_stop)
1596 {
1597         struct tcf_action_egdev_cb *egdev_cb;
1598         int ok_count = 0;
1599         int err;
1600
1601         list_for_each_entry(egdev_cb, &egdev->cb_list, list) {
1602                 err = egdev_cb->cb(type, type_data, egdev_cb->cb_priv);
1603                 if (err) {
1604                         if (err_stop)
1605                                 return err;
1606                 } else {
1607                         ok_count++;
1608                 }
1609         }
1610         return ok_count;
1611 }
1612
1613 static int tcf_action_egdev_cb_add(struct tcf_action_egdev *egdev,
1614                                    tc_setup_cb_t *cb, void *cb_priv)
1615 {
1616         struct tcf_action_egdev_cb *egdev_cb;
1617
1618         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1619         if (WARN_ON(egdev_cb))
1620                 return -EEXIST;
1621         egdev_cb = kzalloc(sizeof(*egdev_cb), GFP_KERNEL);
1622         if (!egdev_cb)
1623                 return -ENOMEM;
1624         egdev_cb->cb = cb;
1625         egdev_cb->cb_priv = cb_priv;
1626         list_add(&egdev_cb->list, &egdev->cb_list);
1627         return 0;
1628 }
1629
1630 static void tcf_action_egdev_cb_del(struct tcf_action_egdev *egdev,
1631                                     tc_setup_cb_t *cb, void *cb_priv)
1632 {
1633         struct tcf_action_egdev_cb *egdev_cb;
1634
1635         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1636         if (WARN_ON(!egdev_cb))
1637                 return;
1638         list_del(&egdev_cb->list);
1639         kfree(egdev_cb);
1640 }
1641
1642 static int __tc_setup_cb_egdev_register(const struct net_device *dev,
1643                                         tc_setup_cb_t *cb, void *cb_priv)
1644 {
1645         struct tcf_action_egdev *egdev = tcf_action_egdev_get(dev);
1646         int err;
1647
1648         if (!egdev)
1649                 return -ENOMEM;
1650         err = tcf_action_egdev_cb_add(egdev, cb, cb_priv);
1651         if (err)
1652                 goto err_cb_add;
1653         return 0;
1654
1655 err_cb_add:
1656         tcf_action_egdev_put(egdev);
1657         return err;
1658 }
1659 int tc_setup_cb_egdev_register(const struct net_device *dev,
1660                                tc_setup_cb_t *cb, void *cb_priv)
1661 {
1662         int err;
1663
1664         rtnl_lock();
1665         err = __tc_setup_cb_egdev_register(dev, cb, cb_priv);
1666         rtnl_unlock();
1667         return err;
1668 }
1669 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_register);
1670
1671 static void __tc_setup_cb_egdev_unregister(const struct net_device *dev,
1672                                            tc_setup_cb_t *cb, void *cb_priv)
1673 {
1674         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1675
1676         if (WARN_ON(!egdev))
1677                 return;
1678         tcf_action_egdev_cb_del(egdev, cb, cb_priv);
1679         tcf_action_egdev_put(egdev);
1680 }
1681 void tc_setup_cb_egdev_unregister(const struct net_device *dev,
1682                                   tc_setup_cb_t *cb, void *cb_priv)
1683 {
1684         rtnl_lock();
1685         __tc_setup_cb_egdev_unregister(dev, cb, cb_priv);
1686         rtnl_unlock();
1687 }
1688 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_unregister);
1689
1690 int tc_setup_cb_egdev_call(const struct net_device *dev,
1691                            enum tc_setup_type type, void *type_data,
1692                            bool err_stop)
1693 {
1694         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1695
1696         if (!egdev)
1697                 return 0;
1698         return tcf_action_egdev_cb_call(egdev, type, type_data, err_stop);
1699 }
1700 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_call);
1701
1702 static __net_init int tcf_action_net_init(struct net *net)
1703 {
1704         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1705
1706         return rhashtable_init(&tan->egdev_ht, &tcf_action_egdev_ht_params);
1707 }
1708
1709 static void __net_exit tcf_action_net_exit(struct net *net)
1710 {
1711         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1712
1713         rhashtable_destroy(&tan->egdev_ht);
1714 }
1715
1716 static struct pernet_operations tcf_action_net_ops = {
1717         .init = tcf_action_net_init,
1718         .exit = tcf_action_net_exit,
1719         .id = &tcf_action_net_id,
1720         .size = sizeof(struct tcf_action_net),
1721 };
1722
1723 static int __init tc_action_init(void)
1724 {
1725         int err;
1726
1727         err = register_pernet_subsys(&tcf_action_net_ops);
1728         if (err)
1729                 return err;
1730
1731         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
1732         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
1733         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1734                       0);
1735
1736         return 0;
1737 }
1738
1739 subsys_initcall(tc_action_init);