net/sched/cls_u32.c

   1 /*
   2  * net/sched/cls_u32.c  Ugly (or Universal) 32bit key Packet Classifier.
   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  * Authors:     Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
  10  *
  11  *      The filters are packed to hash tables of key nodes
  12  *      with a set of 32bit key/mask pairs at every node.
  13  *      Nodes reference next level hash tables etc.
  14  *
  15  *      This scheme is the best universal classifier I managed to
  16  *      invent; it is not super-fast, but it is not slow (provided you
  17  *      program it correctly), and general enough.  And its relative
  18  *      speed grows as the number of rules becomes larger.
  19  *
  20  *      It seems that it represents the best middle point between
  21  *      speed and manageability both by human and by machine.
  22  *
  23  *      It is especially useful for link sharing combined with QoS;
  24  *      pure RSVP doesn't need such a general approach and can use
  25  *      much simpler (and faster) schemes, sort of cls_rsvp.c.
  26  *
  27  *      JHS: We should remove the CONFIG_NET_CLS_IND from here
  28  *      eventually when the meta match extension is made available
  29  *
  30  *      nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
  31  */
  32
  33 #include <linux/module.h>
  34 #include <linux/slab.h>
  35 #include <linux/types.h>
  36 #include <linux/kernel.h>
  37 #include <linux/string.h>
  38 #include <linux/errno.h>
  39 #include <linux/rtnetlink.h>
  40 #include <linux/skbuff.h>
  41 #include <net/netlink.h>
  42 #include <net/act_api.h>
  43 #include <net/pkt_cls.h>
  44
  45 struct tc_u_knode {
  46         struct tc_u_knode       *next;
  47         u32                     handle;
  48         struct tc_u_hnode       *ht_up;
  49         struct tcf_exts         exts;
  50 #ifdef CONFIG_NET_CLS_IND
  51         int                     ifindex;
  52 #endif
  53         u8                      fshift;
  54         struct tcf_result       res;
  55         struct tc_u_hnode       *ht_down;
  56 #ifdef CONFIG_CLS_U32_PERF
  57         struct tc_u32_pcnt      *pf;
  58 #endif
  59 #ifdef CONFIG_CLS_U32_MARK
  60         struct tc_u32_mark      mark;
  61 #endif
  62         struct tc_u32_sel       sel;
  63 };
  64
  65 struct tc_u_hnode {
  66         struct tc_u_hnode       *next;
  67         u32                     handle;
  68         u32                     prio;
  69         struct tc_u_common      *tp_c;
  70         int                     refcnt;
  71         unsigned int            divisor;
  72         struct tc_u_knode       *ht[1];
  73 };
  74
  75 struct tc_u_common {
  76         struct tc_u_hnode       *hlist;
  77         struct Qdisc            *q;
  78         int                     refcnt;
  79         u32                     hgenerator;
  80 };
  81
  82 static inline unsigned int u32_hash_fold(__be32 key,
  83                                          const struct tc_u32_sel *sel,
  84                                          u8 fshift)
  85 {
  86         unsigned int h = ntohl(key & sel->hmask) >> fshift;
  87
  88         return h;
  89 }
  90
  91 static int u32_classify(struct sk_buff *skb, const struct tcf_proto *tp, struct tcf_result *res)
  92 {
  93         struct {
  94                 struct tc_u_knode *knode;
  95                 unsigned int      off;
  96         } stack[TC_U32_MAXDEPTH];
  97
  98         struct tc_u_hnode *ht = tp->root;
  99         unsigned int off = skb_network_offset(skb);
 100         struct tc_u_knode *n;
 101         int sdepth = 0;
 102         int off2 = 0;
 103         int sel = 0;
 104 #ifdef CONFIG_CLS_U32_PERF
 105         int j;
 106 #endif
 107         int i, r;
 108
 109 next_ht:
 110         n = ht->ht[sel];
 111
 112 next_knode:
 113         if (n) {
 114                 struct tc_u32_key *key = n->sel.keys;
 115
 116 #ifdef CONFIG_CLS_U32_PERF
 117                 n->pf->rcnt += 1;
 118                 j = 0;
 119 #endif
 120
 121 #ifdef CONFIG_CLS_U32_MARK
 122                 if ((skb->mark & n->mark.mask) != n->mark.val) {
 123                         n = n->next;
 124                         goto next_knode;
 125                 } else {
 126                         n->mark.success++;
 127                 }
 128 #endif
 129
 130                 for (i = n->sel.nkeys; i > 0; i--, key++) {
 131                         int toff = off + key->off + (off2 & key->offmask);
 132                         __be32 *data, hdata;
 133
 134                         if (skb_headroom(skb) + toff > INT_MAX)
 135                                 goto out;
 136
 137                         data = skb_header_pointer(skb, toff, 4, &hdata);
 138                         if (!data)
 139                                 goto out;
 140                         if ((*data ^ key->val) & key->mask) {
 141                                 n = n->next;
 142                                 goto next_knode;
 143                         }
 144 #ifdef CONFIG_CLS_U32_PERF
 145                         n->pf->kcnts[j] += 1;
 146                         j++;
 147 #endif
 148                 }
 149                 if (n->ht_down == NULL) {
 150 check_terminal:
 151                         if (n->sel.flags & TC_U32_TERMINAL) {
 152
 153                                 *res = n->res;
 154 #ifdef CONFIG_NET_CLS_IND
 155                                 if (!tcf_match_indev(skb, n->ifindex)) {
 156                                         n = n->next;
 157                                         goto next_knode;
 158                                 }
 159 #endif
 160 #ifdef CONFIG_CLS_U32_PERF
 161                                 n->pf->rhit += 1;
 162 #endif
 163                                 r = tcf_exts_exec(skb, &n->exts, res);
 164                                 if (r < 0) {
 165                                         n = n->next;
 166                                         goto next_knode;
 167                                 }
 168
 169                                 return r;
 170                         }
 171                         n = n->next;
 172                         goto next_knode;
 173                 }
 174
 175                 /* PUSH */
 176                 if (sdepth >= TC_U32_MAXDEPTH)
 177                         goto deadloop;
 178                 stack[sdepth].knode = n;
 179                 stack[sdepth].off = off;
 180                 sdepth++;
 181
 182                 ht = n->ht_down;
 183                 sel = 0;
 184                 if (ht->divisor) {
 185                         __be32 *data, hdata;
 186
 187                         data = skb_header_pointer(skb, off + n->sel.hoff, 4,
 188                                                   &hdata);
 189                         if (!data)
 190                                 goto out;
 191                         sel = ht->divisor & u32_hash_fold(*data, &n->sel,
 192                                                           n->fshift);
 193                 }
 194                 if (!(n->sel.flags & (TC_U32_VAROFFSET | TC_U32_OFFSET | TC_U32_EAT)))
 195                         goto next_ht;
 196
 197                 if (n->sel.flags & (TC_U32_OFFSET | TC_U32_VAROFFSET)) {
 198                         off2 = n->sel.off + 3;
 199                         if (n->sel.flags & TC_U32_VAROFFSET) {
 200                                 __be16 *data, hdata;
 201
 202                                 data = skb_header_pointer(skb,
 203                                                           off + n->sel.offoff,
 204                                                           2, &hdata);
 205                                 if (!data)
 206                                         goto out;
 207                                 off2 += ntohs(n->sel.offmask & *data) >>
 208                                         n->sel.offshift;
 209                         }
 210                         off2 &= ~3;
 211                 }
 212                 if (n->sel.flags & TC_U32_EAT) {
 213                         off += off2;
 214                         off2 = 0;
 215                 }
 216
 217                 if (off < skb->len)
 218                         goto next_ht;
 219         }
 220
 221         /* POP */
 222         if (sdepth--) {
 223                 n = stack[sdepth].knode;
 224                 ht = n->ht_up;
 225                 off = stack[sdepth].off;
 226                 goto check_terminal;
 227         }
 228 out:
 229         return -1;
 230
 231 deadloop:
 232         net_warn_ratelimited("cls_u32: dead loop\n");
 233         return -1;
 234 }
 235
 236 static struct tc_u_hnode *
 237 u32_lookup_ht(struct tc_u_common *tp_c, u32 handle)
 238 {
 239         struct tc_u_hnode *ht;
 240
 241         for (ht = tp_c->hlist; ht; ht = ht->next)
 242                 if (ht->handle == handle)
 243                         break;
 244
 245         return ht;
 246 }
 247
 248 static struct tc_u_knode *
 249 u32_lookup_key(struct tc_u_hnode *ht, u32 handle)
 250 {
 251         unsigned int sel;
 252         struct tc_u_knode *n = NULL;
 253
 254         sel = TC_U32_HASH(handle);
 255         if (sel > ht->divisor)
 256                 goto out;
 257
 258         for (n = ht->ht[sel]; n; n = n->next)
 259                 if (n->handle == handle)
 260                         break;
 261 out:
 262         return n;
 263 }
 264
 265
 266 static unsigned long u32_get(struct tcf_proto *tp, u32 handle)
 267 {
 268         struct tc_u_hnode *ht;
 269         struct tc_u_common *tp_c = tp->data;
 270
 271         if (TC_U32_HTID(handle) == TC_U32_ROOT)
 272                 ht = tp->root;
 273         else
 274                 ht = u32_lookup_ht(tp_c, TC_U32_HTID(handle));
 275
 276         if (!ht)
 277                 return 0;
 278
 279         if (TC_U32_KEY(handle) == 0)
 280                 return (unsigned long)ht;
 281
 282         return (unsigned long)u32_lookup_key(ht, handle);
 283 }
 284
 285 static void u32_put(struct tcf_proto *tp, unsigned long f)
 286 {
 287 }
 288
 289 static u32 gen_new_htid(struct tc_u_common *tp_c)
 290 {
 291         int i = 0x800;
 292
 293         do {
 294                 if (++tp_c->hgenerator == 0x7FF)
 295                         tp_c->hgenerator = 1;
 296         } while (--i > 0 && u32_lookup_ht(tp_c, (tp_c->hgenerator|0x800)<<20));
 297
 298         return i > 0 ? (tp_c->hgenerator|0x800)<<20 : 0;
 299 }
 300
 301 static int u32_init(struct tcf_proto *tp)
 302 {
 303         struct tc_u_hnode *root_ht;
 304         struct tc_u_common *tp_c;
 305
 306         tp_c = tp->q->u32_node;
 307
 308         root_ht = kzalloc(sizeof(*root_ht), GFP_KERNEL);
 309         if (root_ht == NULL)
 310                 return -ENOBUFS;
 311
 312         root_ht->divisor = 0;
 313         root_ht->refcnt++;
 314         root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
 315         root_ht->prio = tp->prio;
 316
 317         if (tp_c == NULL) {
 318                 tp_c = kzalloc(sizeof(*tp_c), GFP_KERNEL);
 319                 if (tp_c == NULL) {
 320                         kfree(root_ht);
 321                         return -ENOBUFS;
 322                 }
 323                 tp_c->q = tp->q;
 324                 tp->q->u32_node = tp_c;
 325         }
 326
 327         tp_c->refcnt++;
 328         root_ht->next = tp_c->hlist;
 329         tp_c->hlist = root_ht;
 330         root_ht->tp_c = tp_c;
 331
 332         tp->root = root_ht;
 333         tp->data = tp_c;
 334         return 0;
 335 }
 336
 337 static int u32_destroy_key(struct tcf_proto *tp, struct tc_u_knode *n)
 338 {
 339         tcf_unbind_filter(tp, &n->res);
 340         tcf_exts_destroy(tp, &n->exts);
 341         if (n->ht_down)
 342                 n->ht_down->refcnt--;
 343 #ifdef CONFIG_CLS_U32_PERF
 344         kfree(n->pf);
 345 #endif
 346         kfree(n);
 347         return 0;
 348 }
 349
 350 static int u32_delete_key(struct tcf_proto *tp, struct tc_u_knode *key)
 351 {
 352         struct tc_u_knode **kp;
 353         struct tc_u_hnode *ht = key->ht_up;
 354
 355         if (ht) {
 356                 for (kp = &ht->ht[TC_U32_HASH(key->handle)]; *kp; kp = &(*kp)->next) {
 357                         if (*kp == key) {
 358                                 tcf_tree_lock(tp);
 359                                 *kp = key->next;
 360                                 tcf_tree_unlock(tp);
 361
 362                                 u32_destroy_key(tp, key);
 363                                 return 0;
 364                         }
 365                 }
 366         }
 367         WARN_ON(1);
 368         return 0;
 369 }
 370
 371 static void u32_clear_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 372 {
 373         struct tc_u_knode *n;
 374         unsigned int h;
 375
 376         for (h = 0; h <= ht->divisor; h++) {
 377                 while ((n = ht->ht[h]) != NULL) {
 378                         ht->ht[h] = n->next;
 379
 380                         u32_destroy_key(tp, n);
 381                 }
 382         }
 383 }
 384
 385 static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht)
 386 {
 387         struct tc_u_common *tp_c = tp->data;
 388         struct tc_u_hnode **hn;
 389
 390         WARN_ON(ht->refcnt);
 391
 392         u32_clear_hnode(tp, ht);
 393
 394         for (hn = &tp_c->hlist; *hn; hn = &(*hn)->next) {
 395                 if (*hn == ht) {
 396                         *hn = ht->next;
 397                         kfree(ht);
 398                         return 0;
 399                 }
 400         }
 401
 402         WARN_ON(1);
 403         return -ENOENT;
 404 }
 405
 406 static void u32_destroy(struct tcf_proto *tp)
 407 {
 408         struct tc_u_common *tp_c = tp->data;
 409         struct tc_u_hnode *root_ht = tp->root;
 410
 411         WARN_ON(root_ht == NULL);
 412
 413         if (root_ht && --root_ht->refcnt == 0)
 414                 u32_destroy_hnode(tp, root_ht);
 415
 416         if (--tp_c->refcnt == 0) {
 417                 struct tc_u_hnode *ht;
 418
 419                 tp->q->u32_node = NULL;
 420
 421                 for (ht = tp_c->hlist; ht; ht = ht->next) {
 422                         ht->refcnt--;
 423                         u32_clear_hnode(tp, ht);
 424                 }
 425
 426                 while ((ht = tp_c->hlist) != NULL) {
 427                         tp_c->hlist = ht->next;
 428
 429                         WARN_ON(ht->refcnt != 0);
 430
 431                         kfree(ht);
 432                 }
 433
 434                 kfree(tp_c);
 435         }
 436
 437         tp->data = NULL;
 438 }
 439
 440 static int u32_delete(struct tcf_proto *tp, unsigned long arg)
 441 {
 442         struct tc_u_hnode *ht = (struct tc_u_hnode *)arg;
 443
 444         if (ht == NULL)
 445                 return 0;
 446
 447         if (TC_U32_KEY(ht->handle))
 448                 return u32_delete_key(tp, (struct tc_u_knode *)ht);
 449
 450         if (tp->root == ht)
 451                 return -EINVAL;
 452
 453         if (ht->refcnt == 1) {
 454                 ht->refcnt--;
 455                 u32_destroy_hnode(tp, ht);
 456         } else {
 457                 return -EBUSY;
 458         }
 459
 460         return 0;
 461 }
 462
 463 static u32 gen_new_kid(struct tc_u_hnode *ht, u32 handle)
 464 {
 465         struct tc_u_knode *n;
 466         unsigned int i = 0x7FF;
 467
 468         for (n = ht->ht[TC_U32_HASH(handle)]; n; n = n->next)
 469                 if (i < TC_U32_NODE(n->handle))
 470                         i = TC_U32_NODE(n->handle);
 471         i++;
 472
 473         return handle | (i > 0xFFF ? 0xFFF : i);
 474 }
 475
 476 static const struct nla_policy u32_policy[TCA_U32_MAX + 1] = {
 477         [TCA_U32_CLASSID]       = { .type = NLA_U32 },
 478         [TCA_U32_HASH]          = { .type = NLA_U32 },
 479         [TCA_U32_LINK]          = { .type = NLA_U32 },
 480         [TCA_U32_DIVISOR]       = { .type = NLA_U32 },
 481         [TCA_U32_SEL]           = { .len = sizeof(struct tc_u32_sel) },
 482         [TCA_U32_INDEV]         = { .type = NLA_STRING, .len = IFNAMSIZ },
 483         [TCA_U32_MARK]          = { .len = sizeof(struct tc_u32_mark) },
 484 };
 485
 486 static int u32_set_parms(struct net *net, struct tcf_proto *tp,
 487                          unsigned long base, struct tc_u_hnode *ht,
 488                          struct tc_u_knode *n, struct nlattr **tb,
 489                          struct nlattr *est, bool ovr)
 490 {
 491         int err;
 492         struct tcf_exts e;
 493
 494         tcf_exts_init(&e, TCA_U32_ACT, TCA_U32_POLICE);
 495         err = tcf_exts_validate(net, tp, tb, est, &e, ovr);
 496         if (err < 0)
 497                 return err;
 498
 499         err = -EINVAL;
 500         if (tb[TCA_U32_LINK]) {
 501                 u32 handle = nla_get_u32(tb[TCA_U32_LINK]);
 502                 struct tc_u_hnode *ht_down = NULL, *ht_old;
 503
 504                 if (TC_U32_KEY(handle))
 505                         goto errout;
 506
 507                 if (handle) {
 508                         ht_down = u32_lookup_ht(ht->tp_c, handle);
 509
 510                         if (ht_down == NULL)
 511                                 goto errout;
 512                         ht_down->refcnt++;
 513                 }
 514
 515                 tcf_tree_lock(tp);
 516                 ht_old = n->ht_down;
 517                 n->ht_down = ht_down;
 518                 tcf_tree_unlock(tp);
 519
 520                 if (ht_old)
 521                         ht_old->refcnt--;
 522         }
 523         if (tb[TCA_U32_CLASSID]) {
 524                 n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]);
 525                 tcf_bind_filter(tp, &n->res, base);
 526         }
 527
 528 #ifdef CONFIG_NET_CLS_IND
 529         if (tb[TCA_U32_INDEV]) {
 530                 int ret;
 531                 ret = tcf_change_indev(net, tb[TCA_U32_INDEV]);
 532                 if (ret < 0)
 533                         goto errout;
 534                 n->ifindex = ret;
 535         }
 536 #endif
 537         tcf_exts_change(tp, &n->exts, &e);
 538
 539         return 0;
 540 errout:
 541         tcf_exts_destroy(tp, &e);
 542         return err;
 543 }
 544
 545 static int u32_change(struct net *net, struct sk_buff *in_skb,
 546                       struct tcf_proto *tp, unsigned long base, u32 handle,
 547                       struct nlattr **tca,
 548                       unsigned long *arg, bool ovr)
 549 {
 550         struct tc_u_common *tp_c = tp->data;
 551         struct tc_u_hnode *ht;
 552         struct tc_u_knode *n;
 553         struct tc_u32_sel *s;
 554         struct nlattr *opt = tca[TCA_OPTIONS];
 555         struct nlattr *tb[TCA_U32_MAX + 1];
 556         u32 htid;
 557         int err;
 558
 559         if (opt == NULL)
 560                 return handle ? -EINVAL : 0;
 561
 562         err = nla_parse_nested(tb, TCA_U32_MAX, opt, u32_policy);
 563         if (err < 0)
 564                 return err;
 565
 566         n = (struct tc_u_knode *)*arg;
 567         if (n) {
 568                 if (TC_U32_KEY(n->handle) == 0)
 569                         return -EINVAL;
 570
 571                 return u32_set_parms(net, tp, base, n->ht_up, n, tb,
 572                                      tca[TCA_RATE], ovr);
 573         }
 574
 575         if (tb[TCA_U32_DIVISOR]) {
 576                 unsigned int divisor = nla_get_u32(tb[TCA_U32_DIVISOR]);
 577
 578                 if (--divisor > 0x100)
 579                         return -EINVAL;
 580                 if (TC_U32_KEY(handle))
 581                         return -EINVAL;
 582                 if (handle == 0) {
 583                         handle = gen_new_htid(tp->data);
 584                         if (handle == 0)
 585                                 return -ENOMEM;
 586                 }
 587                 ht = kzalloc(sizeof(*ht) + divisor*sizeof(void *), GFP_KERNEL);
 588                 if (ht == NULL)
 589                         return -ENOBUFS;
 590                 ht->tp_c = tp_c;
 591                 ht->refcnt = 1;
 592                 ht->divisor = divisor;
 593                 ht->handle = handle;
 594                 ht->prio = tp->prio;
 595                 ht->next = tp_c->hlist;
 596                 tp_c->hlist = ht;
 597                 *arg = (unsigned long)ht;
 598                 return 0;
 599         }
 600
 601         if (tb[TCA_U32_HASH]) {
 602                 htid = nla_get_u32(tb[TCA_U32_HASH]);
 603                 if (TC_U32_HTID(htid) == TC_U32_ROOT) {
 604                         ht = tp->root;
 605                         htid = ht->handle;
 606                 } else {
 607                         ht = u32_lookup_ht(tp->data, TC_U32_HTID(htid));
 608                         if (ht == NULL)
 609                                 return -EINVAL;
 610                 }
 611         } else {
 612                 ht = tp->root;
 613                 htid = ht->handle;
 614         }
 615
 616         if (ht->divisor < TC_U32_HASH(htid))
 617                 return -EINVAL;
 618
 619         if (handle) {
 620                 if (TC_U32_HTID(handle) && TC_U32_HTID(handle^htid))
 621                         return -EINVAL;
 622                 handle = htid | TC_U32_NODE(handle);
 623         } else
 624                 handle = gen_new_kid(ht, htid);
 625
 626         if (tb[TCA_U32_SEL] == NULL)
 627                 return -EINVAL;
 628
 629         s = nla_data(tb[TCA_U32_SEL]);
 630
 631         n = kzalloc(sizeof(*n) + s->nkeys*sizeof(struct tc_u32_key), GFP_KERNEL);
 632         if (n == NULL)
 633                 return -ENOBUFS;
 634
 635 #ifdef CONFIG_CLS_U32_PERF
 636         n->pf = kzalloc(sizeof(struct tc_u32_pcnt) + s->nkeys*sizeof(u64), GFP_KERNEL);
 637         if (n->pf == NULL) {
 638                 kfree(n);
 639                 return -ENOBUFS;
 640         }
 641 #endif
 642
 643         memcpy(&n->sel, s, sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key));
 644         n->ht_up = ht;
 645         n->handle = handle;
 646         n->fshift = s->hmask ? ffs(ntohl(s->hmask)) - 1 : 0;
 647         tcf_exts_init(&n->exts, TCA_U32_ACT, TCA_U32_POLICE);
 648
 649 #ifdef CONFIG_CLS_U32_MARK
 650         if (tb[TCA_U32_MARK]) {
 651                 struct tc_u32_mark *mark;
 652
 653                 mark = nla_data(tb[TCA_U32_MARK]);
 654                 memcpy(&n->mark, mark, sizeof(struct tc_u32_mark));
 655                 n->mark.success = 0;
 656         }
 657 #endif
 658
 659         err = u32_set_parms(net, tp, base, ht, n, tb, tca[TCA_RATE], ovr);
 660         if (err == 0) {
 661                 struct tc_u_knode **ins;
 662                 for (ins = &ht->ht[TC_U32_HASH(handle)]; *ins; ins = &(*ins)->next)
 663                         if (TC_U32_NODE(handle) < TC_U32_NODE((*ins)->handle))
 664                                 break;
 665
 666                 n->next = *ins;
 667                 tcf_tree_lock(tp);
 668                 *ins = n;
 669                 tcf_tree_unlock(tp);
 670
 671                 *arg = (unsigned long)n;
 672                 return 0;
 673         }
 674 #ifdef CONFIG_CLS_U32_PERF
 675         kfree(n->pf);
 676 #endif
 677         kfree(n);
 678         return err;
 679 }
 680
 681 static void u32_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 682 {
 683         struct tc_u_common *tp_c = tp->data;
 684         struct tc_u_hnode *ht;
 685         struct tc_u_knode *n;
 686         unsigned int h;
 687
 688         if (arg->stop)
 689                 return;
 690
 691         for (ht = tp_c->hlist; ht; ht = ht->next) {
 692                 if (ht->prio != tp->prio)
 693                         continue;
 694                 if (arg->count >= arg->skip) {
 695                         if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
 696                                 arg->stop = 1;
 697                                 return;
 698                         }
 699                 }
 700                 arg->count++;
 701                 for (h = 0; h <= ht->divisor; h++) {
 702                         for (n = ht->ht[h]; n; n = n->next) {
 703                                 if (arg->count < arg->skip) {
 704                                         arg->count++;
 705                                         continue;
 706                                 }
 707                                 if (arg->fn(tp, (unsigned long)n, arg) < 0) {
 708                                         arg->stop = 1;
 709                                         return;
 710                                 }
 711                                 arg->count++;
 712                         }
 713                 }
 714         }
 715 }
 716
 717 static int u32_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 718                      struct sk_buff *skb, struct tcmsg *t)
 719 {
 720         struct tc_u_knode *n = (struct tc_u_knode *)fh;
 721         struct nlattr *nest;
 722
 723         if (n == NULL)
 724                 return skb->len;
 725
 726         t->tcm_handle = n->handle;
 727
 728         nest = nla_nest_start(skb, TCA_OPTIONS);
 729         if (nest == NULL)
 730                 goto nla_put_failure;
 731
 732         if (TC_U32_KEY(n->handle) == 0) {
 733                 struct tc_u_hnode *ht = (struct tc_u_hnode *)fh;
 734                 u32 divisor = ht->divisor + 1;
 735
 736                 if (nla_put_u32(skb, TCA_U32_DIVISOR, divisor))
 737                         goto nla_put_failure;
 738         } else {
 739                 if (nla_put(skb, TCA_U32_SEL,
 740                             sizeof(n->sel) + n->sel.nkeys*sizeof(struct tc_u32_key),
 741                             &n->sel))
 742                         goto nla_put_failure;
 743                 if (n->ht_up) {
 744                         u32 htid = n->handle & 0xFFFFF000;
 745                         if (nla_put_u32(skb, TCA_U32_HASH, htid))
 746                                 goto nla_put_failure;
 747                 }
 748                 if (n->res.classid &&
 749                     nla_put_u32(skb, TCA_U32_CLASSID, n->res.classid))
 750                         goto nla_put_failure;
 751                 if (n->ht_down &&
 752                     nla_put_u32(skb, TCA_U32_LINK, n->ht_down->handle))
 753                         goto nla_put_failure;
 754
 755 #ifdef CONFIG_CLS_U32_MARK
 756                 if ((n->mark.val || n->mark.mask) &&
 757                     nla_put(skb, TCA_U32_MARK, sizeof(n->mark), &n->mark))
 758                         goto nla_put_failure;
 759 #endif
 760
 761                 if (tcf_exts_dump(skb, &n->exts) < 0)
 762                         goto nla_put_failure;
 763
 764 #ifdef CONFIG_NET_CLS_IND
 765                 if (n->ifindex) {
 766                         struct net_device *dev;
 767                         dev = __dev_get_by_index(net, n->ifindex);
 768                         if (dev && nla_put_string(skb, TCA_U32_INDEV, dev->name))
 769                                 goto nla_put_failure;
 770                 }
 771 #endif
 772 #ifdef CONFIG_CLS_U32_PERF
 773                 if (nla_put(skb, TCA_U32_PCNT,
 774                             sizeof(struct tc_u32_pcnt) + n->sel.nkeys*sizeof(u64),
 775                             n->pf))
 776                         goto nla_put_failure;
 777 #endif
 778         }
 779
 780         nla_nest_end(skb, nest);
 781
 782         if (TC_U32_KEY(n->handle))
 783                 if (tcf_exts_dump_stats(skb, &n->exts) < 0)
 784                         goto nla_put_failure;
 785         return skb->len;
 786
 787 nla_put_failure:
 788         nla_nest_cancel(skb, nest);
 789         return -1;
 790 }
 791
 792 static struct tcf_proto_ops cls_u32_ops __read_mostly = {
 793         .kind           =       "u32",
 794         .classify       =       u32_classify,
 795         .init           =       u32_init,
 796         .destroy        =       u32_destroy,
 797         .get            =       u32_get,
 798         .put            =       u32_put,
 799         .change         =       u32_change,
 800         .delete         =       u32_delete,
 801         .walk           =       u32_walk,
 802         .dump           =       u32_dump,
 803         .owner          =       THIS_MODULE,
 804 };
 805
 806 static int __init init_u32(void)
 807 {
 808         pr_info("u32 classifier\n");
 809 #ifdef CONFIG_CLS_U32_PERF
 810         pr_info("    Performance counters on\n");
 811 #endif
 812 #ifdef CONFIG_NET_CLS_IND
 813         pr_info("    input device check on\n");
 814 #endif
 815 #ifdef CONFIG_NET_CLS_ACT
 816         pr_info("    Actions configured\n");
 817 #endif
 818         return register_tcf_proto_ops(&cls_u32_ops);
 819 }
 820
 821 static void __exit exit_u32(void)
 822 {
 823         unregister_tcf_proto_ops(&cls_u32_ops);
 824 }
 825
 826 module_init(init_u32)
 827 module_exit(exit_u32)
 828 MODULE_LICENSE("GPL");