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_destroy_1(struct tc_action *a, int bind)
 666 {
 667         struct tc_action *actions[] = { a, NULL };
 668
 669         return tcf_action_destroy(actions, bind);
 670 }
 671
 672 static int tcf_action_put(struct tc_action *p)
 673 {
 674         return __tcf_action_put(p, false);
 675 }
 676
 677 /* Put all actions in this array, skip those NULL's. */
 678 static void tcf_action_put_many(struct tc_action *actions[])
 679 {
 680         int i;
 681
 682         for (i = 0; i < TCA_ACT_MAX_PRIO; i++) {
 683                 struct tc_action *a = actions[i];
 684                 const struct tc_action_ops *ops;
 685
 686                 if (!a)
 687                         continue;
 688                 ops = a->ops;
 689                 if (tcf_action_put(a))
 690                         module_put(ops->owner);
 691         }
 692 }
 693
 694 int
 695 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 696 {
 697         return a->ops->dump(skb, a, bind, ref);
 698 }
 699
 700 int
 701 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 702 {
 703         int err = -EINVAL;
 704         unsigned char *b = skb_tail_pointer(skb);
 705         struct nlattr *nest;
 706         struct tc_cookie *cookie;
 707
 708         if (nla_put_string(skb, TCA_KIND, a->ops->kind))
 709                 goto nla_put_failure;
 710         if (tcf_action_copy_stats(skb, a, 0))
 711                 goto nla_put_failure;
 712
 713         rcu_read_lock();
 714         cookie = rcu_dereference(a->act_cookie);
 715         if (cookie) {
 716                 if (nla_put(skb, TCA_ACT_COOKIE, cookie->len, cookie->data)) {
 717                         rcu_read_unlock();
 718                         goto nla_put_failure;
 719                 }
 720         }
 721         rcu_read_unlock();
 722
 723         nest = nla_nest_start(skb, TCA_OPTIONS);
 724         if (nest == NULL)
 725                 goto nla_put_failure;
 726         err = tcf_action_dump_old(skb, a, bind, ref);
 727         if (err > 0) {
 728                 nla_nest_end(skb, nest);
 729                 return err;
 730         }
 731
 732 nla_put_failure:
 733         nlmsg_trim(skb, b);
 734         return -1;
 735 }
 736 EXPORT_SYMBOL(tcf_action_dump_1);
 737
 738 int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[],
 739                     int bind, int ref)
 740 {
 741         struct tc_action *a;
 742         int err = -EINVAL, i;
 743         struct nlattr *nest;
 744
 745         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
 746                 a = actions[i];
 747                 nest = nla_nest_start(skb, i + 1);
 748                 if (nest == NULL)
 749                         goto nla_put_failure;
 750                 err = tcf_action_dump_1(skb, a, bind, ref);
 751                 if (err < 0)
 752                         goto errout;
 753                 nla_nest_end(skb, nest);
 754         }
 755
 756         return 0;
 757
 758 nla_put_failure:
 759         err = -EINVAL;
 760 errout:
 761         nla_nest_cancel(skb, nest);
 762         return err;
 763 }
 764
 765 static struct tc_cookie *nla_memdup_cookie(struct nlattr **tb)
 766 {
 767         struct tc_cookie *c = kzalloc(sizeof(*c), GFP_KERNEL);
 768         if (!c)
 769                 return NULL;
 770
 771         c->data = nla_memdup(tb[TCA_ACT_COOKIE], GFP_KERNEL);
 772         if (!c->data) {
 773                 kfree(c);
 774                 return NULL;
 775         }
 776         c->len = nla_len(tb[TCA_ACT_COOKIE]);
 777
 778         return c;
 779 }
 780
 781 static bool tcf_action_valid(int action)
 782 {
 783         int opcode = TC_ACT_EXT_OPCODE(action);
 784
 785         if (!opcode)
 786                 return action <= TC_ACT_VALUE_MAX;
 787         return opcode <= TC_ACT_EXT_OPCODE_MAX || action == TC_ACT_UNSPEC;
 788 }
 789
 790 struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp,
 791                                     struct nlattr *nla, struct nlattr *est,
 792                                     char *name, int ovr, int bind,
 793                                     bool rtnl_held,
 794                                     struct netlink_ext_ack *extack)
 795 {
 796         struct tc_action *a;
 797         struct tc_action_ops *a_o;
 798         struct tc_cookie *cookie = NULL;
 799         char act_name[IFNAMSIZ];
 800         struct nlattr *tb[TCA_ACT_MAX + 1];
 801         struct nlattr *kind;
 802         int err;
 803
 804         if (name == NULL) {
 805                 err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
 806                 if (err < 0)
 807                         goto err_out;
 808                 err = -EINVAL;
 809                 kind = tb[TCA_ACT_KIND];
 810                 if (!kind) {
 811                         NL_SET_ERR_MSG(extack, "TC action kind must be specified");
 812                         goto err_out;
 813                 }
 814                 if (nla_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ) {
 815                         NL_SET_ERR_MSG(extack, "TC action name too long");
 816                         goto err_out;
 817                 }
 818                 if (tb[TCA_ACT_COOKIE]) {
 819                         int cklen = nla_len(tb[TCA_ACT_COOKIE]);
 820
 821                         if (cklen > TC_COOKIE_MAX_SIZE) {
 822                                 NL_SET_ERR_MSG(extack, "TC cookie size above the maximum");
 823                                 goto err_out;
 824                         }
 825
 826                         cookie = nla_memdup_cookie(tb);
 827                         if (!cookie) {
 828                                 NL_SET_ERR_MSG(extack, "No memory to generate TC cookie");
 829                                 err = -ENOMEM;
 830                                 goto err_out;
 831                         }
 832                 }
 833         } else {
 834                 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ) {
 835                         NL_SET_ERR_MSG(extack, "TC action name too long");
 836                         err = -EINVAL;
 837                         goto err_out;
 838                 }
 839         }
 840
 841         a_o = tc_lookup_action_n(act_name);
 842         if (a_o == NULL) {
 843 #ifdef CONFIG_MODULES
 844                 if (rtnl_held)
 845                         rtnl_unlock();
 846                 request_module("act_%s", act_name);
 847                 if (rtnl_held)
 848                         rtnl_lock();
 849
 850                 a_o = tc_lookup_action_n(act_name);
 851
 852                 /* We dropped the RTNL semaphore in order to
 853                  * perform the module load.  So, even if we
 854                  * succeeded in loading the module we have to
 855                  * tell the caller to replay the request.  We
 856                  * indicate this using -EAGAIN.
 857                  */
 858                 if (a_o != NULL) {
 859                         err = -EAGAIN;
 860                         goto err_mod;
 861                 }
 862 #endif
 863                 NL_SET_ERR_MSG(extack, "Failed to load TC action module");
 864                 err = -ENOENT;
 865                 goto err_out;
 866         }
 867
 868         /* backward compatibility for policer */
 869         if (name == NULL)
 870                 err = a_o->init(net, tb[TCA_ACT_OPTIONS], est, &a, ovr, bind,
 871                                 rtnl_held, extack);
 872         else
 873                 err = a_o->init(net, nla, est, &a, ovr, bind, rtnl_held,
 874                                 extack);
 875         if (err < 0)
 876                 goto err_mod;
 877
 878         if (!name && tb[TCA_ACT_COOKIE])
 879                 tcf_set_action_cookie(&a->act_cookie, cookie);
 880
 881         /* module count goes up only when brand new policy is created
 882          * if it exists and is only bound to in a_o->init() then
 883          * ACT_P_CREATED is not returned (a zero is).
 884          */
 885         if (err != ACT_P_CREATED)
 886                 module_put(a_o->owner);
 887
 888         if (TC_ACT_EXT_CMP(a->tcfa_action, TC_ACT_GOTO_CHAIN)) {
 889                 err = tcf_action_goto_chain_init(a, tp);
 890                 if (err) {
 891                         tcf_action_destroy_1(a, bind);
 892                         NL_SET_ERR_MSG(extack, "Failed to init TC action chain");
 893                         return ERR_PTR(err);
 894                 }
 895         }
 896
 897         if (!tcf_action_valid(a->tcfa_action)) {
 898                 tcf_action_destroy_1(a, bind);
 899                 NL_SET_ERR_MSG(extack, "Invalid control action value");
 900                 return ERR_PTR(-EINVAL);
 901         }
 902
 903         if (!bind && ovr && err == ACT_P_CREATED)
 904                 refcount_set(&a->tcfa_refcnt, 2);
 905
 906         return a;
 907
 908 err_mod:
 909         module_put(a_o->owner);
 910 err_out:
 911         if (cookie) {
 912                 kfree(cookie->data);
 913                 kfree(cookie);
 914         }
 915         return ERR_PTR(err);
 916 }
 917
 918 /* Returns numbers of initialized actions or negative error. */
 919
 920 int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla,
 921                     struct nlattr *est, char *name, int ovr, int bind,
 922                     struct tc_action *actions[], size_t *attr_size,
 923                     bool rtnl_held, struct netlink_ext_ack *extack)
 924 {
 925         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
 926         struct tc_action *act;
 927         size_t sz = 0;
 928         int err;
 929         int i;
 930
 931         err = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
 932         if (err < 0)
 933                 return err;
 934
 935         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
 936                 act = tcf_action_init_1(net, tp, tb[i], est, name, ovr, bind,
 937                                         rtnl_held, extack);
 938                 if (IS_ERR(act)) {
 939                         err = PTR_ERR(act);
 940                         goto err;
 941                 }
 942                 act->order = i;
 943                 sz += tcf_action_fill_size(act);
 944                 /* Start from index 0 */
 945                 actions[i - 1] = act;
 946         }
 947
 948         *attr_size = tcf_action_full_attrs_size(sz);
 949         return i - 1;
 950
 951 err:
 952         tcf_action_destroy(actions, bind);
 953         return err;
 954 }
 955
 956 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *p,
 957                           int compat_mode)
 958 {
 959         int err = 0;
 960         struct gnet_dump d;
 961
 962         if (p == NULL)
 963                 goto errout;
 964
 965         /* compat_mode being true specifies a call that is supposed
 966          * to add additional backward compatibility statistic TLVs.
 967          */
 968         if (compat_mode) {
 969                 if (p->type == TCA_OLD_COMPAT)
 970                         err = gnet_stats_start_copy_compat(skb, 0,
 971                                                            TCA_STATS,
 972                                                            TCA_XSTATS,
 973                                                            &p->tcfa_lock, &d,
 974                                                            TCA_PAD);
 975                 else
 976                         return 0;
 977         } else
 978                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
 979                                             &p->tcfa_lock, &d, TCA_ACT_PAD);
 980
 981         if (err < 0)
 982                 goto errout;
 983
 984         if (gnet_stats_copy_basic(NULL, &d, p->cpu_bstats, &p->tcfa_bstats) < 0 ||
 985             gnet_stats_copy_rate_est(&d, &p->tcfa_rate_est) < 0 ||
 986             gnet_stats_copy_queue(&d, p->cpu_qstats,
 987                                   &p->tcfa_qstats,
 988                                   p->tcfa_qstats.qlen) < 0)
 989                 goto errout;
 990
 991         if (gnet_stats_finish_copy(&d) < 0)
 992                 goto errout;
 993
 994         return 0;
 995
 996 errout:
 997         return -1;
 998 }
 999
1000 static int tca_get_fill(struct sk_buff *skb, struct tc_action *actions[],
1001                         u32 portid, u32 seq, u16 flags, int event, int bind,
1002                         int ref)
1003 {
1004         struct tcamsg *t;
1005         struct nlmsghdr *nlh;
1006         unsigned char *b = skb_tail_pointer(skb);
1007         struct nlattr *nest;
1008
1009         nlh = nlmsg_put(skb, portid, seq, event, sizeof(*t), flags);
1010         if (!nlh)
1011                 goto out_nlmsg_trim;
1012         t = nlmsg_data(nlh);
1013         t->tca_family = AF_UNSPEC;
1014         t->tca__pad1 = 0;
1015         t->tca__pad2 = 0;
1016
1017         nest = nla_nest_start(skb, TCA_ACT_TAB);
1018         if (!nest)
1019                 goto out_nlmsg_trim;
1020
1021         if (tcf_action_dump(skb, actions, bind, ref) < 0)
1022                 goto out_nlmsg_trim;
1023
1024         nla_nest_end(skb, nest);
1025
1026         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1027         return skb->len;
1028
1029 out_nlmsg_trim:
1030         nlmsg_trim(skb, b);
1031         return -1;
1032 }
1033
1034 static int
1035 tcf_get_notify(struct net *net, u32 portid, struct nlmsghdr *n,
1036                struct tc_action *actions[], int event,
1037                struct netlink_ext_ack *extack)
1038 {
1039         struct sk_buff *skb;
1040
1041         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1042         if (!skb)
1043                 return -ENOBUFS;
1044         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, event,
1045                          0, 1) <= 0) {
1046                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1047                 kfree_skb(skb);
1048                 return -EINVAL;
1049         }
1050
1051         return rtnl_unicast(skb, net, portid);
1052 }
1053
1054 static struct tc_action *tcf_action_get_1(struct net *net, struct nlattr *nla,
1055                                           struct nlmsghdr *n, u32 portid,
1056                                           struct netlink_ext_ack *extack)
1057 {
1058         struct nlattr *tb[TCA_ACT_MAX + 1];
1059         const struct tc_action_ops *ops;
1060         struct tc_action *a;
1061         int index;
1062         int err;
1063
1064         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
1065         if (err < 0)
1066                 goto err_out;
1067
1068         err = -EINVAL;
1069         if (tb[TCA_ACT_INDEX] == NULL ||
1070             nla_len(tb[TCA_ACT_INDEX]) < sizeof(index)) {
1071                 NL_SET_ERR_MSG(extack, "Invalid TC action index value");
1072                 goto err_out;
1073         }
1074         index = nla_get_u32(tb[TCA_ACT_INDEX]);
1075
1076         err = -EINVAL;
1077         ops = tc_lookup_action(tb[TCA_ACT_KIND]);
1078         if (!ops) { /* could happen in batch of actions */
1079                 NL_SET_ERR_MSG(extack, "Specified TC action not found");
1080                 goto err_out;
1081         }
1082         err = -ENOENT;
1083         if (ops->lookup(net, &a, index, extack) == 0)
1084                 goto err_mod;
1085
1086         module_put(ops->owner);
1087         return a;
1088
1089 err_mod:
1090         module_put(ops->owner);
1091 err_out:
1092         return ERR_PTR(err);
1093 }
1094
1095 static int tca_action_flush(struct net *net, struct nlattr *nla,
1096                             struct nlmsghdr *n, u32 portid,
1097                             struct netlink_ext_ack *extack)
1098 {
1099         struct sk_buff *skb;
1100         unsigned char *b;
1101         struct nlmsghdr *nlh;
1102         struct tcamsg *t;
1103         struct netlink_callback dcb;
1104         struct nlattr *nest;
1105         struct nlattr *tb[TCA_ACT_MAX + 1];
1106         const struct tc_action_ops *ops;
1107         struct nlattr *kind;
1108         int err = -ENOMEM;
1109
1110         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1111         if (!skb)
1112                 return err;
1113
1114         b = skb_tail_pointer(skb);
1115
1116         err = nla_parse_nested(tb, TCA_ACT_MAX, nla, NULL, extack);
1117         if (err < 0)
1118                 goto err_out;
1119
1120         err = -EINVAL;
1121         kind = tb[TCA_ACT_KIND];
1122         ops = tc_lookup_action(kind);
1123         if (!ops) { /*some idjot trying to flush unknown action */
1124                 NL_SET_ERR_MSG(extack, "Cannot flush unknown TC action");
1125                 goto err_out;
1126         }
1127
1128         nlh = nlmsg_put(skb, portid, n->nlmsg_seq, RTM_DELACTION,
1129                         sizeof(*t), 0);
1130         if (!nlh) {
1131                 NL_SET_ERR_MSG(extack, "Failed to create TC action flush notification");
1132                 goto out_module_put;
1133         }
1134         t = nlmsg_data(nlh);
1135         t->tca_family = AF_UNSPEC;
1136         t->tca__pad1 = 0;
1137         t->tca__pad2 = 0;
1138
1139         nest = nla_nest_start(skb, TCA_ACT_TAB);
1140         if (!nest) {
1141                 NL_SET_ERR_MSG(extack, "Failed to add new netlink message");
1142                 goto out_module_put;
1143         }
1144
1145         err = ops->walk(net, skb, &dcb, RTM_DELACTION, ops, extack);
1146         if (err <= 0) {
1147                 nla_nest_cancel(skb, nest);
1148                 goto out_module_put;
1149         }
1150
1151         nla_nest_end(skb, nest);
1152
1153         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1154         nlh->nlmsg_flags |= NLM_F_ROOT;
1155         module_put(ops->owner);
1156         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1157                              n->nlmsg_flags & NLM_F_ECHO);
1158         if (err > 0)
1159                 return 0;
1160         if (err < 0)
1161                 NL_SET_ERR_MSG(extack, "Failed to send TC action flush notification");
1162
1163         return err;
1164
1165 out_module_put:
1166         module_put(ops->owner);
1167 err_out:
1168         kfree_skb(skb);
1169         return err;
1170 }
1171
1172 static int tcf_action_delete(struct net *net, struct tc_action *actions[])
1173 {
1174         int i;
1175
1176         for (i = 0; i < TCA_ACT_MAX_PRIO && actions[i]; i++) {
1177                 struct tc_action *a = actions[i];
1178                 const struct tc_action_ops *ops = a->ops;
1179                 /* Actions can be deleted concurrently so we must save their
1180                  * type and id to search again after reference is released.
1181                  */
1182                 struct tcf_idrinfo *idrinfo = a->idrinfo;
1183                 u32 act_index = a->tcfa_index;
1184
1185                 actions[i] = NULL;
1186                 if (tcf_action_put(a)) {
1187                         /* last reference, action was deleted concurrently */
1188                         module_put(ops->owner);
1189                 } else  {
1190                         int ret;
1191
1192                         /* now do the delete */
1193                         ret = tcf_idr_delete_index(idrinfo, act_index);
1194                         if (ret < 0)
1195                                 return ret;
1196                 }
1197         }
1198         return 0;
1199 }
1200
1201 static int
1202 tcf_del_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1203                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1204 {
1205         int ret;
1206         struct sk_buff *skb;
1207
1208         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1209                         GFP_KERNEL);
1210         if (!skb)
1211                 return -ENOBUFS;
1212
1213         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, 0, RTM_DELACTION,
1214                          0, 2) <= 0) {
1215                 NL_SET_ERR_MSG(extack, "Failed to fill netlink TC action attributes");
1216                 kfree_skb(skb);
1217                 return -EINVAL;
1218         }
1219
1220         /* now do the delete */
1221         ret = tcf_action_delete(net, actions);
1222         if (ret < 0) {
1223                 NL_SET_ERR_MSG(extack, "Failed to delete TC action");
1224                 kfree_skb(skb);
1225                 return ret;
1226         }
1227
1228         ret = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1229                              n->nlmsg_flags & NLM_F_ECHO);
1230         if (ret > 0)
1231                 return 0;
1232         return ret;
1233 }
1234
1235 static int
1236 tca_action_gd(struct net *net, struct nlattr *nla, struct nlmsghdr *n,
1237               u32 portid, int event, struct netlink_ext_ack *extack)
1238 {
1239         int i, ret;
1240         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1241         struct tc_action *act;
1242         size_t attr_size = 0;
1243         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1244
1245         ret = nla_parse_nested(tb, TCA_ACT_MAX_PRIO, nla, NULL, extack);
1246         if (ret < 0)
1247                 return ret;
1248
1249         if (event == RTM_DELACTION && n->nlmsg_flags & NLM_F_ROOT) {
1250                 if (tb[1])
1251                         return tca_action_flush(net, tb[1], n, portid, extack);
1252
1253                 NL_SET_ERR_MSG(extack, "Invalid netlink attributes while flushing TC action");
1254                 return -EINVAL;
1255         }
1256
1257         for (i = 1; i <= TCA_ACT_MAX_PRIO && tb[i]; i++) {
1258                 act = tcf_action_get_1(net, tb[i], n, portid, extack);
1259                 if (IS_ERR(act)) {
1260                         ret = PTR_ERR(act);
1261                         goto err;
1262                 }
1263                 attr_size += tcf_action_fill_size(act);
1264                 actions[i - 1] = act;
1265         }
1266
1267         attr_size = tcf_action_full_attrs_size(attr_size);
1268
1269         if (event == RTM_GETACTION)
1270                 ret = tcf_get_notify(net, portid, n, actions, event, extack);
1271         else { /* delete */
1272                 ret = tcf_del_notify(net, n, actions, portid, attr_size, extack);
1273                 if (ret)
1274                         goto err;
1275                 return 0;
1276         }
1277 err:
1278         tcf_action_put_many(actions);
1279         return ret;
1280 }
1281
1282 static int
1283 tcf_add_notify(struct net *net, struct nlmsghdr *n, struct tc_action *actions[],
1284                u32 portid, size_t attr_size, struct netlink_ext_ack *extack)
1285 {
1286         struct sk_buff *skb;
1287         int err = 0;
1288
1289         skb = alloc_skb(attr_size <= NLMSG_GOODSIZE ? NLMSG_GOODSIZE : attr_size,
1290                         GFP_KERNEL);
1291         if (!skb)
1292                 return -ENOBUFS;
1293
1294         if (tca_get_fill(skb, actions, portid, n->nlmsg_seq, n->nlmsg_flags,
1295                          RTM_NEWACTION, 0, 0) <= 0) {
1296                 NL_SET_ERR_MSG(extack, "Failed to fill netlink attributes while adding TC action");
1297                 kfree_skb(skb);
1298                 return -EINVAL;
1299         }
1300
1301         err = rtnetlink_send(skb, net, portid, RTNLGRP_TC,
1302                              n->nlmsg_flags & NLM_F_ECHO);
1303         if (err > 0)
1304                 err = 0;
1305         return err;
1306 }
1307
1308 static int tcf_action_add(struct net *net, struct nlattr *nla,
1309                           struct nlmsghdr *n, u32 portid, int ovr,
1310                           struct netlink_ext_ack *extack)
1311 {
1312         size_t attr_size = 0;
1313         int loop, ret;
1314         struct tc_action *actions[TCA_ACT_MAX_PRIO] = {};
1315
1316         for (loop = 0; loop < 10; loop++) {
1317                 ret = tcf_action_init(net, NULL, nla, NULL, NULL, ovr, 0,
1318                                       actions, &attr_size, true, extack);
1319                 if (ret != -EAGAIN)
1320                         break;
1321         }
1322
1323         if (ret < 0)
1324                 return ret;
1325         ret = tcf_add_notify(net, n, actions, portid, attr_size, extack);
1326         if (ovr)
1327                 tcf_action_put_many(actions);
1328
1329         return ret;
1330 }
1331
1332 static u32 tcaa_root_flags_allowed = TCA_FLAG_LARGE_DUMP_ON;
1333 static const struct nla_policy tcaa_policy[TCA_ROOT_MAX + 1] = {
1334         [TCA_ROOT_FLAGS] = { .type = NLA_BITFIELD32,
1335                              .validation_data = &tcaa_root_flags_allowed },
1336         [TCA_ROOT_TIME_DELTA]      = { .type = NLA_U32 },
1337 };
1338
1339 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n,
1340                          struct netlink_ext_ack *extack)
1341 {
1342         struct net *net = sock_net(skb->sk);
1343         struct nlattr *tca[TCA_ROOT_MAX + 1];
1344         u32 portid = skb ? NETLINK_CB(skb).portid : 0;
1345         int ret = 0, ovr = 0;
1346
1347         if ((n->nlmsg_type != RTM_GETACTION) &&
1348             !netlink_capable(skb, CAP_NET_ADMIN))
1349                 return -EPERM;
1350
1351         ret = nlmsg_parse(n, sizeof(struct tcamsg), tca, TCA_ROOT_MAX, NULL,
1352                           extack);
1353         if (ret < 0)
1354                 return ret;
1355
1356         if (tca[TCA_ACT_TAB] == NULL) {
1357                 NL_SET_ERR_MSG(extack, "Netlink action attributes missing");
1358                 return -EINVAL;
1359         }
1360
1361         /* n->nlmsg_flags & NLM_F_CREATE */
1362         switch (n->nlmsg_type) {
1363         case RTM_NEWACTION:
1364                 /* we are going to assume all other flags
1365                  * imply create only if it doesn't exist
1366                  * Note that CREATE | EXCL implies that
1367                  * but since we want avoid ambiguity (eg when flags
1368                  * is zero) then just set this
1369                  */
1370                 if (n->nlmsg_flags & NLM_F_REPLACE)
1371                         ovr = 1;
1372                 ret = tcf_action_add(net, tca[TCA_ACT_TAB], n, portid, ovr,
1373                                      extack);
1374                 break;
1375         case RTM_DELACTION:
1376                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1377                                     portid, RTM_DELACTION, extack);
1378                 break;
1379         case RTM_GETACTION:
1380                 ret = tca_action_gd(net, tca[TCA_ACT_TAB], n,
1381                                     portid, RTM_GETACTION, extack);
1382                 break;
1383         default:
1384                 BUG();
1385         }
1386
1387         return ret;
1388 }
1389
1390 static struct nlattr *find_dump_kind(struct nlattr **nla)
1391 {
1392         struct nlattr *tb1, *tb2[TCA_ACT_MAX + 1];
1393         struct nlattr *tb[TCA_ACT_MAX_PRIO + 1];
1394         struct nlattr *kind;
1395
1396         tb1 = nla[TCA_ACT_TAB];
1397         if (tb1 == NULL)
1398                 return NULL;
1399
1400         if (nla_parse(tb, TCA_ACT_MAX_PRIO, nla_data(tb1),
1401                       NLMSG_ALIGN(nla_len(tb1)), NULL, NULL) < 0)
1402                 return NULL;
1403
1404         if (tb[1] == NULL)
1405                 return NULL;
1406         if (nla_parse_nested(tb2, TCA_ACT_MAX, tb[1], NULL, NULL) < 0)
1407                 return NULL;
1408         kind = tb2[TCA_ACT_KIND];
1409
1410         return kind;
1411 }
1412
1413 static int tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
1414 {
1415         struct net *net = sock_net(skb->sk);
1416         struct nlmsghdr *nlh;
1417         unsigned char *b = skb_tail_pointer(skb);
1418         struct nlattr *nest;
1419         struct tc_action_ops *a_o;
1420         int ret = 0;
1421         struct tcamsg *t = (struct tcamsg *) nlmsg_data(cb->nlh);
1422         struct nlattr *tb[TCA_ROOT_MAX + 1];
1423         struct nlattr *count_attr = NULL;
1424         unsigned long jiffy_since = 0;
1425         struct nlattr *kind = NULL;
1426         struct nla_bitfield32 bf;
1427         u32 msecs_since = 0;
1428         u32 act_count = 0;
1429
1430         ret = nlmsg_parse(cb->nlh, sizeof(struct tcamsg), tb, TCA_ROOT_MAX,
1431                           tcaa_policy, NULL);
1432         if (ret < 0)
1433                 return ret;
1434
1435         kind = find_dump_kind(tb);
1436         if (kind == NULL) {
1437                 pr_info("tc_dump_action: action bad kind\n");
1438                 return 0;
1439         }
1440
1441         a_o = tc_lookup_action(kind);
1442         if (a_o == NULL)
1443                 return 0;
1444
1445         cb->args[2] = 0;
1446         if (tb[TCA_ROOT_FLAGS]) {
1447                 bf = nla_get_bitfield32(tb[TCA_ROOT_FLAGS]);
1448                 cb->args[2] = bf.value;
1449         }
1450
1451         if (tb[TCA_ROOT_TIME_DELTA]) {
1452                 msecs_since = nla_get_u32(tb[TCA_ROOT_TIME_DELTA]);
1453         }
1454
1455         nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
1456                         cb->nlh->nlmsg_type, sizeof(*t), 0);
1457         if (!nlh)
1458                 goto out_module_put;
1459
1460         if (msecs_since)
1461                 jiffy_since = jiffies - msecs_to_jiffies(msecs_since);
1462
1463         t = nlmsg_data(nlh);
1464         t->tca_family = AF_UNSPEC;
1465         t->tca__pad1 = 0;
1466         t->tca__pad2 = 0;
1467         cb->args[3] = jiffy_since;
1468         count_attr = nla_reserve(skb, TCA_ROOT_COUNT, sizeof(u32));
1469         if (!count_attr)
1470                 goto out_module_put;
1471
1472         nest = nla_nest_start(skb, TCA_ACT_TAB);
1473         if (nest == NULL)
1474                 goto out_module_put;
1475
1476         ret = a_o->walk(net, skb, cb, RTM_GETACTION, a_o, NULL);
1477         if (ret < 0)
1478                 goto out_module_put;
1479
1480         if (ret > 0) {
1481                 nla_nest_end(skb, nest);
1482                 ret = skb->len;
1483                 act_count = cb->args[1];
1484                 memcpy(nla_data(count_attr), &act_count, sizeof(u32));
1485                 cb->args[1] = 0;
1486         } else
1487                 nlmsg_trim(skb, b);
1488
1489         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1490         if (NETLINK_CB(cb->skb).portid && ret)
1491                 nlh->nlmsg_flags |= NLM_F_MULTI;
1492         module_put(a_o->owner);
1493         return skb->len;
1494
1495 out_module_put:
1496         module_put(a_o->owner);
1497         nlmsg_trim(skb, b);
1498         return skb->len;
1499 }
1500
1501 struct tcf_action_net {
1502         struct rhashtable egdev_ht;
1503 };
1504
1505 static unsigned int tcf_action_net_id;
1506
1507 struct tcf_action_egdev_cb {
1508         struct list_head list;
1509         tc_setup_cb_t *cb;
1510         void *cb_priv;
1511 };
1512
1513 struct tcf_action_egdev {
1514         struct rhash_head ht_node;
1515         const struct net_device *dev;
1516         unsigned int refcnt;
1517         struct list_head cb_list;
1518 };
1519
1520 static const struct rhashtable_params tcf_action_egdev_ht_params = {
1521         .key_offset = offsetof(struct tcf_action_egdev, dev),
1522         .head_offset = offsetof(struct tcf_action_egdev, ht_node),
1523         .key_len = sizeof(const struct net_device *),
1524 };
1525
1526 static struct tcf_action_egdev *
1527 tcf_action_egdev_lookup(const struct net_device *dev)
1528 {
1529         struct net *net = dev_net(dev);
1530         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1531
1532         return rhashtable_lookup_fast(&tan->egdev_ht, &dev,
1533                                       tcf_action_egdev_ht_params);
1534 }
1535
1536 static struct tcf_action_egdev *
1537 tcf_action_egdev_get(const struct net_device *dev)
1538 {
1539         struct tcf_action_egdev *egdev;
1540         struct tcf_action_net *tan;
1541
1542         egdev = tcf_action_egdev_lookup(dev);
1543         if (egdev)
1544                 goto inc_ref;
1545
1546         egdev = kzalloc(sizeof(*egdev), GFP_KERNEL);
1547         if (!egdev)
1548                 return NULL;
1549         INIT_LIST_HEAD(&egdev->cb_list);
1550         egdev->dev = dev;
1551         tan = net_generic(dev_net(dev), tcf_action_net_id);
1552         rhashtable_insert_fast(&tan->egdev_ht, &egdev->ht_node,
1553                                tcf_action_egdev_ht_params);
1554
1555 inc_ref:
1556         egdev->refcnt++;
1557         return egdev;
1558 }
1559
1560 static void tcf_action_egdev_put(struct tcf_action_egdev *egdev)
1561 {
1562         struct tcf_action_net *tan;
1563
1564         if (--egdev->refcnt)
1565                 return;
1566         tan = net_generic(dev_net(egdev->dev), tcf_action_net_id);
1567         rhashtable_remove_fast(&tan->egdev_ht, &egdev->ht_node,
1568                                tcf_action_egdev_ht_params);
1569         kfree(egdev);
1570 }
1571
1572 static struct tcf_action_egdev_cb *
1573 tcf_action_egdev_cb_lookup(struct tcf_action_egdev *egdev,
1574                            tc_setup_cb_t *cb, void *cb_priv)
1575 {
1576         struct tcf_action_egdev_cb *egdev_cb;
1577
1578         list_for_each_entry(egdev_cb, &egdev->cb_list, list)
1579                 if (egdev_cb->cb == cb && egdev_cb->cb_priv == cb_priv)
1580                         return egdev_cb;
1581         return NULL;
1582 }
1583
1584 static int tcf_action_egdev_cb_call(struct tcf_action_egdev *egdev,
1585                                     enum tc_setup_type type,
1586                                     void *type_data, bool err_stop)
1587 {
1588         struct tcf_action_egdev_cb *egdev_cb;
1589         int ok_count = 0;
1590         int err;
1591
1592         list_for_each_entry(egdev_cb, &egdev->cb_list, list) {
1593                 err = egdev_cb->cb(type, type_data, egdev_cb->cb_priv);
1594                 if (err) {
1595                         if (err_stop)
1596                                 return err;
1597                 } else {
1598                         ok_count++;
1599                 }
1600         }
1601         return ok_count;
1602 }
1603
1604 static int tcf_action_egdev_cb_add(struct tcf_action_egdev *egdev,
1605                                    tc_setup_cb_t *cb, void *cb_priv)
1606 {
1607         struct tcf_action_egdev_cb *egdev_cb;
1608
1609         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1610         if (WARN_ON(egdev_cb))
1611                 return -EEXIST;
1612         egdev_cb = kzalloc(sizeof(*egdev_cb), GFP_KERNEL);
1613         if (!egdev_cb)
1614                 return -ENOMEM;
1615         egdev_cb->cb = cb;
1616         egdev_cb->cb_priv = cb_priv;
1617         list_add(&egdev_cb->list, &egdev->cb_list);
1618         return 0;
1619 }
1620
1621 static void tcf_action_egdev_cb_del(struct tcf_action_egdev *egdev,
1622                                     tc_setup_cb_t *cb, void *cb_priv)
1623 {
1624         struct tcf_action_egdev_cb *egdev_cb;
1625
1626         egdev_cb = tcf_action_egdev_cb_lookup(egdev, cb, cb_priv);
1627         if (WARN_ON(!egdev_cb))
1628                 return;
1629         list_del(&egdev_cb->list);
1630         kfree(egdev_cb);
1631 }
1632
1633 static int __tc_setup_cb_egdev_register(const struct net_device *dev,
1634                                         tc_setup_cb_t *cb, void *cb_priv)
1635 {
1636         struct tcf_action_egdev *egdev = tcf_action_egdev_get(dev);
1637         int err;
1638
1639         if (!egdev)
1640                 return -ENOMEM;
1641         err = tcf_action_egdev_cb_add(egdev, cb, cb_priv);
1642         if (err)
1643                 goto err_cb_add;
1644         return 0;
1645
1646 err_cb_add:
1647         tcf_action_egdev_put(egdev);
1648         return err;
1649 }
1650 int tc_setup_cb_egdev_register(const struct net_device *dev,
1651                                tc_setup_cb_t *cb, void *cb_priv)
1652 {
1653         int err;
1654
1655         rtnl_lock();
1656         err = __tc_setup_cb_egdev_register(dev, cb, cb_priv);
1657         rtnl_unlock();
1658         return err;
1659 }
1660 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_register);
1661
1662 static void __tc_setup_cb_egdev_unregister(const struct net_device *dev,
1663                                            tc_setup_cb_t *cb, void *cb_priv)
1664 {
1665         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1666
1667         if (WARN_ON(!egdev))
1668                 return;
1669         tcf_action_egdev_cb_del(egdev, cb, cb_priv);
1670         tcf_action_egdev_put(egdev);
1671 }
1672 void tc_setup_cb_egdev_unregister(const struct net_device *dev,
1673                                   tc_setup_cb_t *cb, void *cb_priv)
1674 {
1675         rtnl_lock();
1676         __tc_setup_cb_egdev_unregister(dev, cb, cb_priv);
1677         rtnl_unlock();
1678 }
1679 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_unregister);
1680
1681 int tc_setup_cb_egdev_call(const struct net_device *dev,
1682                            enum tc_setup_type type, void *type_data,
1683                            bool err_stop)
1684 {
1685         struct tcf_action_egdev *egdev = tcf_action_egdev_lookup(dev);
1686
1687         if (!egdev)
1688                 return 0;
1689         return tcf_action_egdev_cb_call(egdev, type, type_data, err_stop);
1690 }
1691 EXPORT_SYMBOL_GPL(tc_setup_cb_egdev_call);
1692
1693 static __net_init int tcf_action_net_init(struct net *net)
1694 {
1695         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1696
1697         return rhashtable_init(&tan->egdev_ht, &tcf_action_egdev_ht_params);
1698 }
1699
1700 static void __net_exit tcf_action_net_exit(struct net *net)
1701 {
1702         struct tcf_action_net *tan = net_generic(net, tcf_action_net_id);
1703
1704         rhashtable_destroy(&tan->egdev_ht);
1705 }
1706
1707 static struct pernet_operations tcf_action_net_ops = {
1708         .init = tcf_action_net_init,
1709         .exit = tcf_action_net_exit,
1710         .id = &tcf_action_net_id,
1711         .size = sizeof(struct tcf_action_net),
1712 };
1713
1714 static int __init tc_action_init(void)
1715 {
1716         int err;
1717
1718         err = register_pernet_subsys(&tcf_action_net_ops);
1719         if (err)
1720                 return err;
1721
1722         rtnl_register(PF_UNSPEC, RTM_NEWACTION, tc_ctl_action, NULL, 0);
1723         rtnl_register(PF_UNSPEC, RTM_DELACTION, tc_ctl_action, NULL, 0);
1724         rtnl_register(PF_UNSPEC, RTM_GETACTION, tc_ctl_action, tc_dump_action,
1725                       0);
1726
1727         return 0;
1728 }
1729
1730 subsys_initcall(tc_action_init);