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 <asm/uaccess.h>
  15 #include <asm/system.h>
  16 #include <linux/bitops.h>
  17 #include <linux/config.h>
  18 #include <linux/types.h>
  19 #include <linux/kernel.h>
  20 #include <linux/sched.h>
  21 #include <linux/string.h>
  22 #include <linux/mm.h>
  23 #include <linux/socket.h>
  24 #include <linux/sockios.h>
  25 #include <linux/in.h>
  26 #include <linux/errno.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/netdevice.h>
  29 #include <linux/skbuff.h>
  30 #include <linux/rtnetlink.h>
  31 #include <linux/init.h>
  32 #include <linux/kmod.h>
  33 #include <net/sock.h>
  34 #include <net/sch_generic.h>
  35 #include <net/act_api.h>
  36
  37 #if 1 /* control */
  38 #define DPRINTK(format, args...) printk(KERN_DEBUG format, ##args)
  39 #else
  40 #define DPRINTK(format, args...)
  41 #endif
  42 #if 0 /* data */
  43 #define D2PRINTK(format, args...) printk(KERN_DEBUG format, ##args)
  44 #else
  45 #define D2PRINTK(format, args...)
  46 #endif
  47
  48 static struct tc_action_ops *act_base = NULL;
  49 static DEFINE_RWLOCK(act_mod_lock);
  50
  51 int tcf_register_action(struct tc_action_ops *act)
  52 {
  53         struct tc_action_ops *a, **ap;
  54
  55         write_lock(&act_mod_lock);
  56         for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
  57                 if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
  58                         write_unlock(&act_mod_lock);
  59                         return -EEXIST;
  60                 }
  61         }
  62         act->next = NULL;
  63         *ap = act;
  64         write_unlock(&act_mod_lock);
  65         return 0;
  66 }
  67
  68 int tcf_unregister_action(struct tc_action_ops *act)
  69 {
  70         struct tc_action_ops *a, **ap;
  71         int err = -ENOENT;
  72
  73         write_lock(&act_mod_lock);
  74         for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
  75                 if (a == act)
  76                         break;
  77         if (a) {
  78                 *ap = a->next;
  79                 a->next = NULL;
  80                 err = 0;
  81         }
  82         write_unlock(&act_mod_lock);
  83         return err;
  84 }
  85
  86 /* lookup by name */
  87 static struct tc_action_ops *tc_lookup_action_n(char *kind)
  88 {
  89         struct tc_action_ops *a = NULL;
  90
  91         if (kind) {
  92                 read_lock(&act_mod_lock);
  93                 for (a = act_base; a; a = a->next) {
  94                         if (strcmp(kind, a->kind) == 0) {
  95                                 if (!try_module_get(a->owner)) {
  96                                         read_unlock(&act_mod_lock);
  97                                         return NULL;
  98                                 }
  99                                 break;
 100                         }
 101                 }
 102                 read_unlock(&act_mod_lock);
 103         }
 104         return a;
 105 }
 106
 107 /* lookup by rtattr */
 108 static struct tc_action_ops *tc_lookup_action(struct rtattr *kind)
 109 {
 110         struct tc_action_ops *a = NULL;
 111
 112         if (kind) {
 113                 read_lock(&act_mod_lock);
 114                 for (a = act_base; a; a = a->next) {
 115                         if (rtattr_strcmp(kind, a->kind) == 0) {
 116                                 if (!try_module_get(a->owner)) {
 117                                         read_unlock(&act_mod_lock);
 118                                         return NULL;
 119                                 }
 120                                 break;
 121                         }
 122                 }
 123                 read_unlock(&act_mod_lock);
 124         }
 125         return a;
 126 }
 127
 128 #if 0
 129 /* lookup by id */
 130 static struct tc_action_ops *tc_lookup_action_id(u32 type)
 131 {
 132         struct tc_action_ops *a = NULL;
 133
 134         if (type) {
 135                 read_lock(&act_mod_lock);
 136                 for (a = act_base; a; a = a->next) {
 137                         if (a->type == type) {
 138                                 if (!try_module_get(a->owner)) {
 139                                         read_unlock(&act_mod_lock);
 140                                         return NULL;
 141                                 }
 142                                 break;
 143                         }
 144                 }
 145                 read_unlock(&act_mod_lock);
 146         }
 147         return a;
 148 }
 149 #endif
 150
 151 int tcf_action_exec(struct sk_buff *skb, struct tc_action *act,
 152                     struct tcf_result *res)
 153 {
 154         struct tc_action *a;
 155         int ret = -1;
 156
 157         if (skb->tc_verd & TC_NCLS) {
 158                 skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
 159                 D2PRINTK("(%p)tcf_action_exec: cleared TC_NCLS in %s out %s\n",
 160                          skb, skb->input_dev ? skb->input_dev->name : "xxx",
 161                          skb->dev->name);
 162                 ret = TC_ACT_OK;
 163                 goto exec_done;
 164         }
 165         while ((a = act) != NULL) {
 166 repeat:
 167                 if (a->ops && a->ops->act) {
 168                         ret = a->ops->act(&skb, a);
 169                         if (TC_MUNGED & skb->tc_verd) {
 170                                 /* copied already, allow trampling */
 171                                 skb->tc_verd = SET_TC_OK2MUNGE(skb->tc_verd);
 172                                 skb->tc_verd = CLR_TC_MUNGED(skb->tc_verd);
 173                         }
 174                         if (ret == TC_ACT_REPEAT)
 175                                 goto repeat;    /* we need a ttl - JHS */
 176                         if (ret != TC_ACT_PIPE)
 177                                 goto exec_done;
 178                 }
 179                 act = a->next;
 180         }
 181 exec_done:
 182         if (skb->tc_classid > 0) {
 183                 res->classid = skb->tc_classid;
 184                 res->class = 0;
 185                 skb->tc_classid = 0;
 186         }
 187         return ret;
 188 }
 189
 190 void tcf_action_destroy(struct tc_action *act, int bind)
 191 {
 192         struct tc_action *a;
 193
 194         for (a = act; a; a = act) {
 195                 if (a->ops && a->ops->cleanup) {
 196                         DPRINTK("tcf_action_destroy destroying %p next %p\n",
 197                                 a, a->next);
 198                         if (a->ops->cleanup(a, bind) == ACT_P_DELETED)
 199                                 module_put(a->ops->owner);
 200                         act = act->next;
 201                         kfree(a);
 202                 } else { /*FIXME: Remove later - catch insertion bugs*/
 203                         printk("tcf_action_destroy: BUG? destroying NULL ops\n");
 204                         act = act->next;
 205                         kfree(a);
 206                 }
 207         }
 208 }
 209
 210 int
 211 tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 212 {
 213         int err = -EINVAL;
 214
 215         if (a->ops == NULL || a->ops->dump == NULL)
 216                 return err;
 217         return a->ops->dump(skb, a, bind, ref);
 218 }
 219
 220 int
 221 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 222 {
 223         int err = -EINVAL;
 224         unsigned char *b = skb->tail;
 225         struct rtattr *r;
 226
 227         if (a->ops == NULL || a->ops->dump == NULL)
 228                 return err;
 229
 230         RTA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
 231         if (tcf_action_copy_stats(skb, a, 0))
 232                 goto rtattr_failure;
 233         r = (struct rtattr*) skb->tail;
 234         RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 235         if ((err = tcf_action_dump_old(skb, a, bind, ref)) > 0) {
 236                 r->rta_len = skb->tail - (u8*)r;
 237                 return err;
 238         }
 239
 240 rtattr_failure:
 241         skb_trim(skb, b - skb->data);
 242         return -1;
 243 }
 244
 245 int
 246 tcf_action_dump(struct sk_buff *skb, struct tc_action *act, int bind, int ref)
 247 {
 248         struct tc_action *a;
 249         int err = -EINVAL;
 250         unsigned char *b = skb->tail;
 251         struct rtattr *r ;
 252
 253         while ((a = act) != NULL) {
 254                 r = (struct rtattr*) skb->tail;
 255                 act = a->next;
 256                 RTA_PUT(skb, a->order, 0, NULL);
 257                 err = tcf_action_dump_1(skb, a, bind, ref);
 258                 if (err < 0)
 259                         goto rtattr_failure;
 260                 r->rta_len = skb->tail - (u8*)r;
 261         }
 262
 263         return 0;
 264
 265 rtattr_failure:
 266         skb_trim(skb, b - skb->data);
 267         return -err;
 268 }
 269
 270 struct tc_action *tcf_action_init_1(struct rtattr *rta, struct rtattr *est,
 271                                     char *name, int ovr, int bind, int *err)
 272 {
 273         struct tc_action *a;
 274         struct tc_action_ops *a_o;
 275         char act_name[IFNAMSIZ];
 276         struct rtattr *tb[TCA_ACT_MAX+1];
 277         struct rtattr *kind;
 278
 279         *err = -EINVAL;
 280
 281         if (name == NULL) {
 282                 if (rtattr_parse_nested(tb, TCA_ACT_MAX, rta) < 0)
 283                         goto err_out;
 284                 kind = tb[TCA_ACT_KIND-1];
 285                 if (kind == NULL)
 286                         goto err_out;
 287                 if (rtattr_strlcpy(act_name, kind, IFNAMSIZ) >= IFNAMSIZ)
 288                         goto err_out;
 289         } else {
 290                 if (strlcpy(act_name, name, IFNAMSIZ) >= IFNAMSIZ)
 291                         goto err_out;
 292         }
 293
 294         a_o = tc_lookup_action_n(act_name);
 295         if (a_o == NULL) {
 296 #ifdef CONFIG_KMOD
 297                 rtnl_unlock();
 298                 request_module(act_name);
 299                 rtnl_lock();
 300
 301                 a_o = tc_lookup_action_n(act_name);
 302
 303                 /* We dropped the RTNL semaphore in order to
 304                  * perform the module load.  So, even if we
 305                  * succeeded in loading the module we have to
 306                  * tell the caller to replay the request.  We
 307                  * indicate this using -EAGAIN.
 308                  */
 309                 if (a_o != NULL) {
 310                         *err = -EAGAIN;
 311                         goto err_mod;
 312                 }
 313 #endif
 314                 goto err_out;
 315         }
 316
 317         *err = -ENOMEM;
 318         a = kmalloc(sizeof(*a), GFP_KERNEL);
 319         if (a == NULL)
 320                 goto err_mod;
 321         memset(a, 0, sizeof(*a));
 322
 323         /* backward compatibility for policer */
 324         if (name == NULL)
 325                 *err = a_o->init(tb[TCA_ACT_OPTIONS-1], est, a, ovr, bind);
 326         else
 327                 *err = a_o->init(rta, est, a, ovr, bind);
 328         if (*err < 0)
 329                 goto err_free;
 330
 331         /* module count goes up only when brand new policy is created
 332            if it exists and is only bound to in a_o->init() then
 333            ACT_P_CREATED is not returned (a zero is).
 334         */
 335         if (*err != ACT_P_CREATED)
 336                 module_put(a_o->owner);
 337         a->ops = a_o;
 338         DPRINTK("tcf_action_init_1: successfull %s\n", act_name);
 339
 340         *err = 0;
 341         return a;
 342
 343 err_free:
 344         kfree(a);
 345 err_mod:
 346         module_put(a_o->owner);
 347 err_out:
 348         return NULL;
 349 }
 350
 351 struct tc_action *tcf_action_init(struct rtattr *rta, struct rtattr *est,
 352                                   char *name, int ovr, int bind, int *err)
 353 {
 354         struct rtattr *tb[TCA_ACT_MAX_PRIO+1];
 355         struct tc_action *head = NULL, *act, *act_prev = NULL;
 356         int i;
 357
 358         if (rtattr_parse_nested(tb, TCA_ACT_MAX_PRIO, rta) < 0) {
 359                 *err = -EINVAL;
 360                 return head;
 361         }
 362
 363         for (i=0; i < TCA_ACT_MAX_PRIO && tb[i]; i++) {
 364                 act = tcf_action_init_1(tb[i], est, name, ovr, bind, err);
 365                 if (act == NULL)
 366                         goto err;
 367                 act->order = i+1;
 368
 369                 if (head == NULL)
 370                         head = act;
 371                 else
 372                         act_prev->next = act;
 373                 act_prev = act;
 374         }
 375         return head;
 376
 377 err:
 378         if (head != NULL)
 379                 tcf_action_destroy(head, bind);
 380         return NULL;
 381 }
 382
 383 int tcf_action_copy_stats(struct sk_buff *skb, struct tc_action *a,
 384                           int compat_mode)
 385 {
 386         int err = 0;
 387         struct gnet_dump d;
 388         struct tcf_act_hdr *h = a->priv;
 389
 390         if (h == NULL)
 391                 goto errout;
 392
 393         /* compat_mode being true specifies a call that is supposed
 394          * to add additional backward compatiblity statistic TLVs.
 395          */
 396         if (compat_mode) {
 397                 if (a->type == TCA_OLD_COMPAT)
 398                         err = gnet_stats_start_copy_compat(skb, 0,
 399                                 TCA_STATS, TCA_XSTATS, h->stats_lock, &d);
 400                 else
 401                         return 0;
 402         } else
 403                 err = gnet_stats_start_copy(skb, TCA_ACT_STATS,
 404                         h->stats_lock, &d);
 405
 406         if (err < 0)
 407                 goto errout;
 408
 409         if (a->ops != NULL && a->ops->get_stats != NULL)
 410                 if (a->ops->get_stats(skb, a) < 0)
 411                         goto errout;
 412
 413         if (gnet_stats_copy_basic(&d, &h->bstats) < 0 ||
 414 #ifdef CONFIG_NET_ESTIMATOR
 415             gnet_stats_copy_rate_est(&d, &h->rate_est) < 0 ||
 416 #endif
 417             gnet_stats_copy_queue(&d, &h->qstats) < 0)
 418                 goto errout;
 419
 420         if (gnet_stats_finish_copy(&d) < 0)
 421                 goto errout;
 422
 423         return 0;
 424
 425 errout:
 426         return -1;
 427 }
 428
 429 static int
 430 tca_get_fill(struct sk_buff *skb, struct tc_action *a, u32 pid, u32 seq,
 431              u16 flags, int event, int bind, int ref)
 432 {
 433         struct tcamsg *t;
 434         struct nlmsghdr *nlh;
 435         unsigned char *b = skb->tail;
 436         struct rtattr *x;
 437
 438         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 439
 440         t = NLMSG_DATA(nlh);
 441         t->tca_family = AF_UNSPEC;
 442         t->tca__pad1 = 0;
 443         t->tca__pad2 = 0;
 444
 445         x = (struct rtattr*) skb->tail;
 446         RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 447
 448         if (tcf_action_dump(skb, a, bind, ref) < 0)
 449                 goto rtattr_failure;
 450
 451         x->rta_len = skb->tail - (u8*)x;
 452
 453         nlh->nlmsg_len = skb->tail - b;
 454         return skb->len;
 455
 456 rtattr_failure:
 457 nlmsg_failure:
 458         skb_trim(skb, b - skb->data);
 459         return -1;
 460 }
 461
 462 static int
 463 act_get_notify(u32 pid, struct nlmsghdr *n, struct tc_action *a, int event)
 464 {
 465         struct sk_buff *skb;
 466         int err = 0;
 467
 468         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 469         if (!skb)
 470                 return -ENOBUFS;
 471         if (tca_get_fill(skb, a, pid, n->nlmsg_seq, 0, event, 0, 0) <= 0) {
 472                 kfree_skb(skb);
 473                 return -EINVAL;
 474         }
 475         err = netlink_unicast(rtnl, skb, pid, MSG_DONTWAIT);
 476         if (err > 0)
 477                 err = 0;
 478         return err;
 479 }
 480
 481 static struct tc_action *
 482 tcf_action_get_1(struct rtattr *rta, struct nlmsghdr *n, u32 pid, int *err)
 483 {
 484         struct rtattr *tb[TCA_ACT_MAX+1];
 485         struct tc_action *a;
 486         int index;
 487
 488         *err = -EINVAL;
 489         if (rtattr_parse_nested(tb, TCA_ACT_MAX, rta) < 0)
 490                 return NULL;
 491
 492         if (tb[TCA_ACT_INDEX - 1] == NULL ||
 493             RTA_PAYLOAD(tb[TCA_ACT_INDEX - 1]) < sizeof(index))
 494                 return NULL;
 495         index = *(int *)RTA_DATA(tb[TCA_ACT_INDEX - 1]);
 496
 497         *err = -ENOMEM;
 498         a = kmalloc(sizeof(struct tc_action), GFP_KERNEL);
 499         if (a == NULL)
 500                 return NULL;
 501         memset(a, 0, sizeof(struct tc_action));
 502
 503         *err = -EINVAL;
 504         a->ops = tc_lookup_action(tb[TCA_ACT_KIND - 1]);
 505         if (a->ops == NULL)
 506                 goto err_free;
 507         if (a->ops->lookup == NULL)
 508                 goto err_mod;
 509         *err = -ENOENT;
 510         if (a->ops->lookup(a, index) == 0)
 511                 goto err_mod;
 512
 513         module_put(a->ops->owner);
 514         *err = 0;
 515         return a;
 516 err_mod:
 517         module_put(a->ops->owner);
 518 err_free:
 519         kfree(a);
 520         return NULL;
 521 }
 522
 523 static void cleanup_a(struct tc_action *act)
 524 {
 525         struct tc_action *a;
 526
 527         for (a = act; a; a = act) {
 528                 act = a->next;
 529                 kfree(a);
 530         }
 531 }
 532
 533 static struct tc_action *create_a(int i)
 534 {
 535         struct tc_action *act;
 536
 537         act = kmalloc(sizeof(*act), GFP_KERNEL);
 538         if (act == NULL) {
 539                 printk("create_a: failed to alloc!\n");
 540                 return NULL;
 541         }
 542         memset(act, 0, sizeof(*act));
 543         act->order = i;
 544         return act;
 545 }
 546
 547 static int tca_action_flush(struct rtattr *rta, struct nlmsghdr *n, u32 pid)
 548 {
 549         struct sk_buff *skb;
 550         unsigned char *b;
 551         struct nlmsghdr *nlh;
 552         struct tcamsg *t;
 553         struct netlink_callback dcb;
 554         struct rtattr *x;
 555         struct rtattr *tb[TCA_ACT_MAX+1];
 556         struct rtattr *kind;
 557         struct tc_action *a = create_a(0);
 558         int err = -EINVAL;
 559
 560         if (a == NULL) {
 561                 printk("tca_action_flush: couldnt create tc_action\n");
 562                 return err;
 563         }
 564
 565         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 566         if (!skb) {
 567                 printk("tca_action_flush: failed skb alloc\n");
 568                 kfree(a);
 569                 return -ENOBUFS;
 570         }
 571
 572         b = (unsigned char *)skb->tail;
 573
 574         if (rtattr_parse_nested(tb, TCA_ACT_MAX, rta) < 0)
 575                 goto err_out;
 576
 577         kind = tb[TCA_ACT_KIND-1];
 578         a->ops = tc_lookup_action(kind);
 579         if (a->ops == NULL)
 580                 goto err_out;
 581
 582         nlh = NLMSG_PUT(skb, pid, n->nlmsg_seq, RTM_DELACTION, sizeof(*t));
 583         t = NLMSG_DATA(nlh);
 584         t->tca_family = AF_UNSPEC;
 585         t->tca__pad1 = 0;
 586         t->tca__pad2 = 0;
 587
 588         x = (struct rtattr *) skb->tail;
 589         RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 590
 591         err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
 592         if (err < 0)
 593                 goto rtattr_failure;
 594
 595         x->rta_len = skb->tail - (u8 *) x;
 596
 597         nlh->nlmsg_len = skb->tail - b;
 598         nlh->nlmsg_flags |= NLM_F_ROOT;
 599         module_put(a->ops->owner);
 600         kfree(a);
 601         err = rtnetlink_send(skb, pid, RTMGRP_TC, n->nlmsg_flags&NLM_F_ECHO);
 602         if (err > 0)
 603                 return 0;
 604
 605         return err;
 606
 607 rtattr_failure:
 608         module_put(a->ops->owner);
 609 nlmsg_failure:
 610 err_out:
 611         kfree_skb(skb);
 612         kfree(a);
 613         return err;
 614 }
 615
 616 static int
 617 tca_action_gd(struct rtattr *rta, struct nlmsghdr *n, u32 pid, int event)
 618 {
 619         int i, ret = 0;
 620         struct rtattr *tb[TCA_ACT_MAX_PRIO+1];
 621         struct tc_action *head = NULL, *act, *act_prev = NULL;
 622
 623         if (rtattr_parse_nested(tb, TCA_ACT_MAX_PRIO, rta) < 0)
 624                 return -EINVAL;
 625
 626         if (event == RTM_DELACTION && n->nlmsg_flags&NLM_F_ROOT) {
 627                 if (tb[0] != NULL && tb[1] == NULL)
 628                         return tca_action_flush(tb[0], n, pid);
 629         }
 630
 631         for (i=0; i < TCA_ACT_MAX_PRIO && tb[i]; i++) {
 632                 act = tcf_action_get_1(tb[i], n, pid, &ret);
 633                 if (act == NULL)
 634                         goto err;
 635                 act->order = i+1;
 636
 637                 if (head == NULL)
 638                         head = act;
 639                 else
 640                         act_prev->next = act;
 641                 act_prev = act;
 642         }
 643
 644         if (event == RTM_GETACTION)
 645                 ret = act_get_notify(pid, n, head, event);
 646         else { /* delete */
 647                 struct sk_buff *skb;
 648
 649                 skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 650                 if (!skb) {
 651                         ret = -ENOBUFS;
 652                         goto err;
 653                 }
 654
 655                 if (tca_get_fill(skb, head, pid, n->nlmsg_seq, 0, event,
 656                                  0, 1) <= 0) {
 657                         kfree_skb(skb);
 658                         ret = -EINVAL;
 659                         goto err;
 660                 }
 661
 662                 /* now do the delete */
 663                 tcf_action_destroy(head, 0);
 664                 ret = rtnetlink_send(skb, pid, RTMGRP_TC,
 665                                      n->nlmsg_flags&NLM_F_ECHO);
 666                 if (ret > 0)
 667                         return 0;
 668                 return ret;
 669         }
 670 err:
 671         cleanup_a(head);
 672         return ret;
 673 }
 674
 675 static int tcf_add_notify(struct tc_action *a, u32 pid, u32 seq, int event,
 676                           u16 flags)
 677 {
 678         struct tcamsg *t;
 679         struct nlmsghdr *nlh;
 680         struct sk_buff *skb;
 681         struct rtattr *x;
 682         unsigned char *b;
 683         int err = 0;
 684
 685         skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
 686         if (!skb)
 687                 return -ENOBUFS;
 688
 689         b = (unsigned char *)skb->tail;
 690
 691         nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 692         t = NLMSG_DATA(nlh);
 693         t->tca_family = AF_UNSPEC;
 694         t->tca__pad1 = 0;
 695         t->tca__pad2 = 0;
 696
 697         x = (struct rtattr*) skb->tail;
 698         RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 699
 700         if (tcf_action_dump(skb, a, 0, 0) < 0)
 701                 goto rtattr_failure;
 702
 703         x->rta_len = skb->tail - (u8*)x;
 704
 705         nlh->nlmsg_len = skb->tail - b;
 706         NETLINK_CB(skb).dst_groups = RTMGRP_TC;
 707
 708         err = rtnetlink_send(skb, pid, RTMGRP_TC, flags&NLM_F_ECHO);
 709         if (err > 0)
 710                 err = 0;
 711         return err;
 712
 713 rtattr_failure:
 714 nlmsg_failure:
 715         skb_trim(skb, b - skb->data);
 716         return -1;
 717 }
 718
 719
 720 static int
 721 tcf_action_add(struct rtattr *rta, struct nlmsghdr *n, u32 pid, int ovr)
 722 {
 723         int ret = 0;
 724         struct tc_action *act;
 725         struct tc_action *a;
 726         u32 seq = n->nlmsg_seq;
 727
 728         act = tcf_action_init(rta, NULL, NULL, ovr, 0, &ret);
 729         if (act == NULL)
 730                 goto done;
 731
 732         /* dump then free all the actions after update; inserted policy
 733          * stays intact
 734          * */
 735         ret = tcf_add_notify(act, pid, seq, RTM_NEWACTION, n->nlmsg_flags);
 736         for (a = act; a; a = act) {
 737                 act = a->next;
 738                 kfree(a);
 739         }
 740 done:
 741         return ret;
 742 }
 743
 744 static int tc_ctl_action(struct sk_buff *skb, struct nlmsghdr *n, void *arg)
 745 {
 746         struct rtattr **tca = arg;
 747         u32 pid = skb ? NETLINK_CB(skb).pid : 0;
 748         int ret = 0, ovr = 0;
 749
 750         if (tca[TCA_ACT_TAB-1] == NULL) {
 751                 printk("tc_ctl_action: received NO action attribs\n");
 752                 return -EINVAL;
 753         }
 754
 755         /* n->nlmsg_flags&NLM_F_CREATE
 756          * */
 757         switch (n->nlmsg_type) {
 758         case RTM_NEWACTION:
 759                 /* we are going to assume all other flags
 760                  * imply create only if it doesnt exist
 761                  * Note that CREATE | EXCL implies that
 762                  * but since we want avoid ambiguity (eg when flags
 763                  * is zero) then just set this
 764                  */
 765                 if (n->nlmsg_flags&NLM_F_REPLACE)
 766                         ovr = 1;
 767 replay:
 768                 ret = tcf_action_add(tca[TCA_ACT_TAB-1], n, pid, ovr);
 769                 if (ret == -EAGAIN)
 770                         goto replay;
 771                 break;
 772         case RTM_DELACTION:
 773                 ret = tca_action_gd(tca[TCA_ACT_TAB-1], n, pid, RTM_DELACTION);
 774                 break;
 775         case RTM_GETACTION:
 776                 ret = tca_action_gd(tca[TCA_ACT_TAB-1], n, pid, RTM_GETACTION);
 777                 break;
 778         default:
 779                 BUG();
 780         }
 781
 782         return ret;
 783 }
 784
 785 static char *
 786 find_dump_kind(struct nlmsghdr *n)
 787 {
 788         struct rtattr *tb1, *tb2[TCA_ACT_MAX+1];
 789         struct rtattr *tb[TCA_ACT_MAX_PRIO + 1];
 790         struct rtattr *rta[TCAA_MAX + 1];
 791         struct rtattr *kind;
 792         int min_len = NLMSG_LENGTH(sizeof(struct tcamsg));
 793         int attrlen = n->nlmsg_len - NLMSG_ALIGN(min_len);
 794         struct rtattr *attr = (void *) n + NLMSG_ALIGN(min_len);
 795
 796         if (rtattr_parse(rta, TCAA_MAX, attr, attrlen) < 0)
 797                 return NULL;
 798         tb1 = rta[TCA_ACT_TAB - 1];
 799         if (tb1 == NULL)
 800                 return NULL;
 801
 802         if (rtattr_parse(tb, TCA_ACT_MAX_PRIO, RTA_DATA(tb1),
 803                          NLMSG_ALIGN(RTA_PAYLOAD(tb1))) < 0)
 804                 return NULL;
 805         if (tb[0] == NULL)
 806                 return NULL;
 807
 808         if (rtattr_parse(tb2, TCA_ACT_MAX, RTA_DATA(tb[0]),
 809                          RTA_PAYLOAD(tb[0])) < 0)
 810                 return NULL;
 811         kind = tb2[TCA_ACT_KIND-1];
 812
 813         return (char *) RTA_DATA(kind);
 814 }
 815
 816 static int
 817 tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
 818 {
 819         struct nlmsghdr *nlh;
 820         unsigned char *b = skb->tail;
 821         struct rtattr *x;
 822         struct tc_action_ops *a_o;
 823         struct tc_action a;
 824         int ret = 0;
 825         struct tcamsg *t = (struct tcamsg *) NLMSG_DATA(cb->nlh);
 826         char *kind = find_dump_kind(cb->nlh);
 827
 828         if (kind == NULL) {
 829                 printk("tc_dump_action: action bad kind\n");
 830                 return 0;
 831         }
 832
 833         a_o = tc_lookup_action_n(kind);
 834         if (a_o == NULL) {
 835                 printk("failed to find %s\n", kind);
 836                 return 0;
 837         }
 838
 839         memset(&a, 0, sizeof(struct tc_action));
 840         a.ops = a_o;
 841
 842         if (a_o->walk == NULL) {
 843                 printk("tc_dump_action: %s !capable of dumping table\n", kind);
 844                 goto rtattr_failure;
 845         }
 846
 847         nlh = NLMSG_PUT(skb, NETLINK_CB(cb->skb).pid, cb->nlh->nlmsg_seq,
 848                         cb->nlh->nlmsg_type, sizeof(*t));
 849         t = NLMSG_DATA(nlh);
 850         t->tca_family = AF_UNSPEC;
 851         t->tca__pad1 = 0;
 852         t->tca__pad2 = 0;
 853
 854         x = (struct rtattr *) skb->tail;
 855         RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 856
 857         ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
 858         if (ret < 0)
 859                 goto rtattr_failure;
 860
 861         if (ret > 0) {
 862                 x->rta_len = skb->tail - (u8 *) x;
 863                 ret = skb->len;
 864         } else
 865                 skb_trim(skb, (u8*)x - skb->data);
 866
 867         nlh->nlmsg_len = skb->tail - b;
 868         if (NETLINK_CB(cb->skb).pid && ret)
 869                 nlh->nlmsg_flags |= NLM_F_MULTI;
 870         module_put(a_o->owner);
 871         return skb->len;
 872
 873 rtattr_failure:
 874 nlmsg_failure:
 875         module_put(a_o->owner);
 876         skb_trim(skb, b - skb->data);
 877         return skb->len;
 878 }
 879
 880 static int __init tc_action_init(void)
 881 {
 882         struct rtnetlink_link *link_p = rtnetlink_links[PF_UNSPEC];
 883
 884         if (link_p) {
 885                 link_p[RTM_NEWACTION-RTM_BASE].doit = tc_ctl_action;
 886                 link_p[RTM_DELACTION-RTM_BASE].doit = tc_ctl_action;
 887                 link_p[RTM_GETACTION-RTM_BASE].doit = tc_ctl_action;
 888                 link_p[RTM_GETACTION-RTM_BASE].dumpit = tc_dump_action;
 889         }
 890
 891         printk("TC classifier action (bugs to netdev@vger.kernel.org cc "
 892                "hadi@cyberus.ca)\n");
 893         return 0;
 894 }
 895
 896 subsys_initcall(tc_action_init);
 897
 898 EXPORT_SYMBOL(tcf_register_action);
 899 EXPORT_SYMBOL(tcf_unregister_action);
 900 EXPORT_SYMBOL(tcf_action_exec);
 901 EXPORT_SYMBOL(tcf_action_dump_1);