net/sched/cls_rsvp.h

   1 /*
   2  * net/sched/cls_rsvp.h Template file for RSVPv[46] classifiers.
   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
  12 /*
  13    Comparing to general packet classification problem,
  14    RSVP needs only sevaral relatively simple rules:
  15
  16    * (dst, protocol) are always specified,
  17      so that we are able to hash them.
  18    * src may be exact, or may be wildcard, so that
  19      we can keep a hash table plus one wildcard entry.
  20    * source port (or flow label) is important only if src is given.
  21
  22    IMPLEMENTATION.
  23
  24    We use a two level hash table: The top level is keyed by
  25    destination address and protocol ID, every bucket contains a list
  26    of "rsvp sessions", identified by destination address, protocol and
  27    DPI(="Destination Port ID"): triple (key, mask, offset).
  28
  29    Every bucket has a smaller hash table keyed by source address
  30    (cf. RSVP flowspec) and one wildcard entry for wildcard reservations.
  31    Every bucket is again a list of "RSVP flows", selected by
  32    source address and SPI(="Source Port ID" here rather than
  33    "security parameter index"): triple (key, mask, offset).
  34
  35
  36    NOTE 1. All the packets with IPv6 extension headers (but AH and ESP)
  37    and all fragmented packets go to the best-effort traffic class.
  38
  39
  40    NOTE 2. Two "port id"'s seems to be redundant, rfc2207 requires
  41    only one "Generalized Port Identifier". So that for classic
  42    ah, esp (and udp,tcp) both *pi should coincide or one of them
  43    should be wildcard.
  44
  45    At first sight, this redundancy is just a waste of CPU
  46    resources. But DPI and SPI add the possibility to assign different
  47    priorities to GPIs. Look also at note 4 about tunnels below.
  48
  49
  50    NOTE 3. One complication is the case of tunneled packets.
  51    We implement it as following: if the first lookup
  52    matches a special session with "tunnelhdr" value not zero,
  53    flowid doesn't contain the true flow ID, but the tunnel ID (1...255).
  54    In this case, we pull tunnelhdr bytes and restart lookup
  55    with tunnel ID added to the list of keys. Simple and stupid 8)8)
  56    It's enough for PIMREG and IPIP.
  57
  58
  59    NOTE 4. Two GPIs make it possible to parse even GRE packets.
  60    F.e. DPI can select ETH_P_IP (and necessary flags to make
  61    tunnelhdr correct) in GRE protocol field and SPI matches
  62    GRE key. Is it not nice? 8)8)
  63
  64
  65    Well, as result, despite its simplicity, we get a pretty
  66    powerful classification engine.  */
  67
  68
  69 struct rsvp_head {
  70         u32                     tmap[256/32];
  71         u32                     hgenerator;
  72         u8                      tgenerator;
  73         struct rsvp_session __rcu *ht[256];
  74         struct rcu_head         rcu;
  75 };
  76
  77 struct rsvp_session {
  78         struct rsvp_session __rcu       *next;
  79         __be32                          dst[RSVP_DST_LEN];
  80         struct tc_rsvp_gpi              dpi;
  81         u8                              protocol;
  82         u8                              tunnelid;
  83         /* 16 (src,sport) hash slots, and one wildcard source slot */
  84         struct rsvp_filter __rcu        *ht[16 + 1];
  85         struct rcu_head                 rcu;
  86 };
  87
  88
  89 struct rsvp_filter {
  90         struct rsvp_filter __rcu        *next;
  91         __be32                          src[RSVP_DST_LEN];
  92         struct tc_rsvp_gpi              spi;
  93         u8                              tunnelhdr;
  94
  95         struct tcf_result               res;
  96         struct tcf_exts                 exts;
  97
  98         u32                             handle;
  99         struct rsvp_session             *sess;
 100         struct rcu_head                 rcu;
 101 };
 102
 103 static inline unsigned int hash_dst(__be32 *dst, u8 protocol, u8 tunnelid)
 104 {
 105         unsigned int h = (__force __u32)dst[RSVP_DST_LEN - 1];
 106
 107         h ^= h>>16;
 108         h ^= h>>8;
 109         return (h ^ protocol ^ tunnelid) & 0xFF;
 110 }
 111
 112 static inline unsigned int hash_src(__be32 *src)
 113 {
 114         unsigned int h = (__force __u32)src[RSVP_DST_LEN-1];
 115
 116         h ^= h>>16;
 117         h ^= h>>8;
 118         h ^= h>>4;
 119         return h & 0xF;
 120 }
 121
 122 #define RSVP_APPLY_RESULT()                             \
 123 {                                                       \
 124         int r = tcf_exts_exec(skb, &f->exts, res);      \
 125         if (r < 0)                                      \
 126                 continue;                               \
 127         else if (r > 0)                                 \
 128                 return r;                               \
 129 }
 130
 131 static int rsvp_classify(struct sk_buff *skb, const struct tcf_proto *tp,
 132                          struct tcf_result *res)
 133 {
 134         struct rsvp_head *head = rcu_dereference_bh(tp->root);
 135         struct rsvp_session *s;
 136         struct rsvp_filter *f;
 137         unsigned int h1, h2;
 138         __be32 *dst, *src;
 139         u8 protocol;
 140         u8 tunnelid = 0;
 141         u8 *xprt;
 142 #if RSVP_DST_LEN == 4
 143         struct ipv6hdr *nhptr;
 144
 145         if (!pskb_network_may_pull(skb, sizeof(*nhptr)))
 146                 return -1;
 147         nhptr = ipv6_hdr(skb);
 148 #else
 149         struct iphdr *nhptr;
 150
 151         if (!pskb_network_may_pull(skb, sizeof(*nhptr)))
 152                 return -1;
 153         nhptr = ip_hdr(skb);
 154 #endif
 155
 156 restart:
 157
 158 #if RSVP_DST_LEN == 4
 159         src = &nhptr->saddr.s6_addr32[0];
 160         dst = &nhptr->daddr.s6_addr32[0];
 161         protocol = nhptr->nexthdr;
 162         xprt = ((u8 *)nhptr) + sizeof(struct ipv6hdr);
 163 #else
 164         src = &nhptr->saddr;
 165         dst = &nhptr->daddr;
 166         protocol = nhptr->protocol;
 167         xprt = ((u8 *)nhptr) + (nhptr->ihl<<2);
 168         if (ip_is_fragment(nhptr))
 169                 return -1;
 170 #endif
 171
 172         h1 = hash_dst(dst, protocol, tunnelid);
 173         h2 = hash_src(src);
 174
 175         for (s = rcu_dereference_bh(head->ht[h1]); s;
 176              s = rcu_dereference_bh(s->next)) {
 177                 if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN - 1] &&
 178                     protocol == s->protocol &&
 179                     !(s->dpi.mask &
 180                       (*(u32 *)(xprt + s->dpi.offset) ^ s->dpi.key)) &&
 181 #if RSVP_DST_LEN == 4
 182                     dst[0] == s->dst[0] &&
 183                     dst[1] == s->dst[1] &&
 184                     dst[2] == s->dst[2] &&
 185 #endif
 186                     tunnelid == s->tunnelid) {
 187
 188                         for (f = rcu_dereference_bh(s->ht[h2]); f;
 189                              f = rcu_dereference_bh(f->next)) {
 190                                 if (src[RSVP_DST_LEN-1] == f->src[RSVP_DST_LEN - 1] &&
 191                                     !(f->spi.mask & (*(u32 *)(xprt + f->spi.offset) ^ f->spi.key))
 192 #if RSVP_DST_LEN == 4
 193                                     &&
 194                                     src[0] == f->src[0] &&
 195                                     src[1] == f->src[1] &&
 196                                     src[2] == f->src[2]
 197 #endif
 198                                     ) {
 199                                         *res = f->res;
 200                                         RSVP_APPLY_RESULT();
 201
 202 matched:
 203                                         if (f->tunnelhdr == 0)
 204                                                 return 0;
 205
 206                                         tunnelid = f->res.classid;
 207                                         nhptr = (void *)(xprt + f->tunnelhdr - sizeof(*nhptr));
 208                                         goto restart;
 209                                 }
 210                         }
 211
 212                         /* And wildcard bucket... */
 213                         for (f = rcu_dereference_bh(s->ht[16]); f;
 214                              f = rcu_dereference_bh(f->next)) {
 215                                 *res = f->res;
 216                                 RSVP_APPLY_RESULT();
 217                                 goto matched;
 218                         }
 219                         return -1;
 220                 }
 221         }
 222         return -1;
 223 }
 224
 225 static void rsvp_replace(struct tcf_proto *tp, struct rsvp_filter *n, u32 h)
 226 {
 227         struct rsvp_head *head = rtnl_dereference(tp->root);
 228         struct rsvp_session *s;
 229         struct rsvp_filter __rcu **ins;
 230         struct rsvp_filter *pins;
 231         unsigned int h1 = h & 0xFF;
 232         unsigned int h2 = (h >> 8) & 0xFF;
 233
 234         for (s = rtnl_dereference(head->ht[h1]); s;
 235              s = rtnl_dereference(s->next)) {
 236                 for (ins = &s->ht[h2], pins = rtnl_dereference(*ins); ;
 237                      ins = &pins->next, pins = rtnl_dereference(*ins)) {
 238                         if (pins->handle == h) {
 239                                 RCU_INIT_POINTER(n->next, pins->next);
 240                                 rcu_assign_pointer(*ins, n);
 241                                 return;
 242                         }
 243                 }
 244         }
 245
 246         /* Something went wrong if we are trying to replace a non-existant
 247          * node. Mind as well halt instead of silently failing.
 248          */
 249         BUG_ON(1);
 250 }
 251
 252 static unsigned long rsvp_get(struct tcf_proto *tp, u32 handle)
 253 {
 254         struct rsvp_head *head = rtnl_dereference(tp->root);
 255         struct rsvp_session *s;
 256         struct rsvp_filter *f;
 257         unsigned int h1 = handle & 0xFF;
 258         unsigned int h2 = (handle >> 8) & 0xFF;
 259
 260         if (h2 > 16)
 261                 return 0;
 262
 263         for (s = rtnl_dereference(head->ht[h1]); s;
 264              s = rtnl_dereference(s->next)) {
 265                 for (f = rtnl_dereference(s->ht[h2]); f;
 266                      f = rtnl_dereference(f->next)) {
 267                         if (f->handle == handle)
 268                                 return (unsigned long)f;
 269                 }
 270         }
 271         return 0;
 272 }
 273
 274 static int rsvp_init(struct tcf_proto *tp)
 275 {
 276         struct rsvp_head *data;
 277
 278         data = kzalloc(sizeof(struct rsvp_head), GFP_KERNEL);
 279         if (data) {
 280                 rcu_assign_pointer(tp->root, data);
 281                 return 0;
 282         }
 283         return -ENOBUFS;
 284 }
 285
 286 static void rsvp_delete_filter_rcu(struct rcu_head *head)
 287 {
 288         struct rsvp_filter *f = container_of(head, struct rsvp_filter, rcu);
 289
 290         tcf_exts_destroy(&f->exts);
 291         kfree(f);
 292 }
 293
 294 static void rsvp_delete_filter(struct tcf_proto *tp, struct rsvp_filter *f)
 295 {
 296         tcf_unbind_filter(tp, &f->res);
 297         /* all classifiers are required to call tcf_exts_destroy() after rcu
 298          * grace period, since converted-to-rcu actions are relying on that
 299          * in cleanup() callback
 300          */
 301         call_rcu(&f->rcu, rsvp_delete_filter_rcu);
 302 }
 303
 304 static bool rsvp_destroy(struct tcf_proto *tp, bool force)
 305 {
 306         struct rsvp_head *data = rtnl_dereference(tp->root);
 307         int h1, h2;
 308
 309         if (data == NULL)
 310                 return true;
 311
 312         if (!force) {
 313                 for (h1 = 0; h1 < 256; h1++) {
 314                         if (rcu_access_pointer(data->ht[h1]))
 315                                 return false;
 316                 }
 317         }
 318
 319         RCU_INIT_POINTER(tp->root, NULL);
 320
 321         for (h1 = 0; h1 < 256; h1++) {
 322                 struct rsvp_session *s;
 323
 324                 while ((s = rtnl_dereference(data->ht[h1])) != NULL) {
 325                         RCU_INIT_POINTER(data->ht[h1], s->next);
 326
 327                         for (h2 = 0; h2 <= 16; h2++) {
 328                                 struct rsvp_filter *f;
 329
 330                                 while ((f = rtnl_dereference(s->ht[h2])) != NULL) {
 331                                         rcu_assign_pointer(s->ht[h2], f->next);
 332                                         rsvp_delete_filter(tp, f);
 333                                 }
 334                         }
 335                         kfree_rcu(s, rcu);
 336                 }
 337         }
 338         kfree_rcu(data, rcu);
 339         return true;
 340 }
 341
 342 static int rsvp_delete(struct tcf_proto *tp, unsigned long arg)
 343 {
 344         struct rsvp_head *head = rtnl_dereference(tp->root);
 345         struct rsvp_filter *nfp, *f = (struct rsvp_filter *)arg;
 346         struct rsvp_filter __rcu **fp;
 347         unsigned int h = f->handle;
 348         struct rsvp_session __rcu **sp;
 349         struct rsvp_session *nsp, *s = f->sess;
 350         int i;
 351
 352         fp = &s->ht[(h >> 8) & 0xFF];
 353         for (nfp = rtnl_dereference(*fp); nfp;
 354              fp = &nfp->next, nfp = rtnl_dereference(*fp)) {
 355                 if (nfp == f) {
 356                         RCU_INIT_POINTER(*fp, f->next);
 357                         rsvp_delete_filter(tp, f);
 358
 359                         /* Strip tree */
 360
 361                         for (i = 0; i <= 16; i++)
 362                                 if (s->ht[i])
 363                                         return 0;
 364
 365                         /* OK, session has no flows */
 366                         sp = &head->ht[h & 0xFF];
 367                         for (nsp = rtnl_dereference(*sp); nsp;
 368                              sp = &nsp->next, nsp = rtnl_dereference(*sp)) {
 369                                 if (nsp == s) {
 370                                         RCU_INIT_POINTER(*sp, s->next);
 371                                         kfree_rcu(s, rcu);
 372                                         return 0;
 373                                 }
 374                         }
 375
 376                         return 0;
 377                 }
 378         }
 379         return 0;
 380 }
 381
 382 static unsigned int gen_handle(struct tcf_proto *tp, unsigned salt)
 383 {
 384         struct rsvp_head *data = rtnl_dereference(tp->root);
 385         int i = 0xFFFF;
 386
 387         while (i-- > 0) {
 388                 u32 h;
 389
 390                 if ((data->hgenerator += 0x10000) == 0)
 391                         data->hgenerator = 0x10000;
 392                 h = data->hgenerator|salt;
 393                 if (rsvp_get(tp, h) == 0)
 394                         return h;
 395         }
 396         return 0;
 397 }
 398
 399 static int tunnel_bts(struct rsvp_head *data)
 400 {
 401         int n = data->tgenerator >> 5;
 402         u32 b = 1 << (data->tgenerator & 0x1F);
 403
 404         if (data->tmap[n] & b)
 405                 return 0;
 406         data->tmap[n] |= b;
 407         return 1;
 408 }
 409
 410 static void tunnel_recycle(struct rsvp_head *data)
 411 {
 412         struct rsvp_session __rcu **sht = data->ht;
 413         u32 tmap[256/32];
 414         int h1, h2;
 415
 416         memset(tmap, 0, sizeof(tmap));
 417
 418         for (h1 = 0; h1 < 256; h1++) {
 419                 struct rsvp_session *s;
 420                 for (s = rtnl_dereference(sht[h1]); s;
 421                      s = rtnl_dereference(s->next)) {
 422                         for (h2 = 0; h2 <= 16; h2++) {
 423                                 struct rsvp_filter *f;
 424
 425                                 for (f = rtnl_dereference(s->ht[h2]); f;
 426                                      f = rtnl_dereference(f->next)) {
 427                                         if (f->tunnelhdr == 0)
 428                                                 continue;
 429                                         data->tgenerator = f->res.classid;
 430                                         tunnel_bts(data);
 431                                 }
 432                         }
 433                 }
 434         }
 435
 436         memcpy(data->tmap, tmap, sizeof(tmap));
 437 }
 438
 439 static u32 gen_tunnel(struct rsvp_head *data)
 440 {
 441         int i, k;
 442
 443         for (k = 0; k < 2; k++) {
 444                 for (i = 255; i > 0; i--) {
 445                         if (++data->tgenerator == 0)
 446                                 data->tgenerator = 1;
 447                         if (tunnel_bts(data))
 448                                 return data->tgenerator;
 449                 }
 450                 tunnel_recycle(data);
 451         }
 452         return 0;
 453 }
 454
 455 static const struct nla_policy rsvp_policy[TCA_RSVP_MAX + 1] = {
 456         [TCA_RSVP_CLASSID]      = { .type = NLA_U32 },
 457         [TCA_RSVP_DST]          = { .type = NLA_BINARY,
 458                                     .len = RSVP_DST_LEN * sizeof(u32) },
 459         [TCA_RSVP_SRC]          = { .type = NLA_BINARY,
 460                                     .len = RSVP_DST_LEN * sizeof(u32) },
 461         [TCA_RSVP_PINFO]        = { .len = sizeof(struct tc_rsvp_pinfo) },
 462 };
 463
 464 static int rsvp_change(struct net *net, struct sk_buff *in_skb,
 465                        struct tcf_proto *tp, unsigned long base,
 466                        u32 handle,
 467                        struct nlattr **tca,
 468                        unsigned long *arg, bool ovr)
 469 {
 470         struct rsvp_head *data = rtnl_dereference(tp->root);
 471         struct rsvp_filter *f, *nfp;
 472         struct rsvp_filter __rcu **fp;
 473         struct rsvp_session *nsp, *s;
 474         struct rsvp_session __rcu **sp;
 475         struct tc_rsvp_pinfo *pinfo = NULL;
 476         struct nlattr *opt = tca[TCA_OPTIONS];
 477         struct nlattr *tb[TCA_RSVP_MAX + 1];
 478         struct tcf_exts e;
 479         unsigned int h1, h2;
 480         __be32 *dst;
 481         int err;
 482
 483         if (opt == NULL)
 484                 return handle ? -EINVAL : 0;
 485
 486         err = nla_parse_nested(tb, TCA_RSVP_MAX, opt, rsvp_policy);
 487         if (err < 0)
 488                 return err;
 489
 490         tcf_exts_init(&e, TCA_RSVP_ACT, TCA_RSVP_POLICE);
 491         err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &e, ovr);
 492         if (err < 0)
 493                 return err;
 494
 495         f = (struct rsvp_filter *)*arg;
 496         if (f) {
 497                 /* Node exists: adjust only classid */
 498                 struct rsvp_filter *n;
 499
 500                 if (f->handle != handle && handle)
 501                         goto errout2;
 502
 503                 n = kmemdup(f, sizeof(*f), GFP_KERNEL);
 504                 if (!n) {
 505                         err = -ENOMEM;
 506                         goto errout2;
 507                 }
 508
 509                 tcf_exts_init(&n->exts, TCA_RSVP_ACT, TCA_RSVP_POLICE);
 510
 511                 if (tb[TCA_RSVP_CLASSID]) {
 512                         n->res.classid = nla_get_u32(tb[TCA_RSVP_CLASSID]);
 513                         tcf_bind_filter(tp, &n->res, base);
 514                 }
 515
 516                 tcf_exts_change(tp, &n->exts, &e);
 517                 rsvp_replace(tp, n, handle);
 518                 return 0;
 519         }
 520
 521         /* Now more serious part... */
 522         err = -EINVAL;
 523         if (handle)
 524                 goto errout2;
 525         if (tb[TCA_RSVP_DST] == NULL)
 526                 goto errout2;
 527
 528         err = -ENOBUFS;
 529         f = kzalloc(sizeof(struct rsvp_filter), GFP_KERNEL);
 530         if (f == NULL)
 531                 goto errout2;
 532
 533         tcf_exts_init(&f->exts, TCA_RSVP_ACT, TCA_RSVP_POLICE);
 534         h2 = 16;
 535         if (tb[TCA_RSVP_SRC]) {
 536                 memcpy(f->src, nla_data(tb[TCA_RSVP_SRC]), sizeof(f->src));
 537                 h2 = hash_src(f->src);
 538         }
 539         if (tb[TCA_RSVP_PINFO]) {
 540                 pinfo = nla_data(tb[TCA_RSVP_PINFO]);
 541                 f->spi = pinfo->spi;
 542                 f->tunnelhdr = pinfo->tunnelhdr;
 543         }
 544         if (tb[TCA_RSVP_CLASSID])
 545                 f->res.classid = nla_get_u32(tb[TCA_RSVP_CLASSID]);
 546
 547         dst = nla_data(tb[TCA_RSVP_DST]);
 548         h1 = hash_dst(dst, pinfo ? pinfo->protocol : 0, pinfo ? pinfo->tunnelid : 0);
 549
 550         err = -ENOMEM;
 551         if ((f->handle = gen_handle(tp, h1 | (h2<<8))) == 0)
 552                 goto errout;
 553
 554         if (f->tunnelhdr) {
 555                 err = -EINVAL;
 556                 if (f->res.classid > 255)
 557                         goto errout;
 558
 559                 err = -ENOMEM;
 560                 if (f->res.classid == 0 &&
 561                     (f->res.classid = gen_tunnel(data)) == 0)
 562                         goto errout;
 563         }
 564
 565         for (sp = &data->ht[h1];
 566              (s = rtnl_dereference(*sp)) != NULL;
 567              sp = &s->next) {
 568                 if (dst[RSVP_DST_LEN-1] == s->dst[RSVP_DST_LEN-1] &&
 569                     pinfo && pinfo->protocol == s->protocol &&
 570                     memcmp(&pinfo->dpi, &s->dpi, sizeof(s->dpi)) == 0 &&
 571 #if RSVP_DST_LEN == 4
 572                     dst[0] == s->dst[0] &&
 573                     dst[1] == s->dst[1] &&
 574                     dst[2] == s->dst[2] &&
 575 #endif
 576                     pinfo->tunnelid == s->tunnelid) {
 577
 578 insert:
 579                         /* OK, we found appropriate session */
 580
 581                         fp = &s->ht[h2];
 582
 583                         f->sess = s;
 584                         if (f->tunnelhdr == 0)
 585                                 tcf_bind_filter(tp, &f->res, base);
 586
 587                         tcf_exts_change(tp, &f->exts, &e);
 588
 589                         fp = &s->ht[h2];
 590                         for (nfp = rtnl_dereference(*fp); nfp;
 591                              fp = &nfp->next, nfp = rtnl_dereference(*fp)) {
 592                                 __u32 mask = nfp->spi.mask & f->spi.mask;
 593
 594                                 if (mask != f->spi.mask)
 595                                         break;
 596                         }
 597                         RCU_INIT_POINTER(f->next, nfp);
 598                         rcu_assign_pointer(*fp, f);
 599
 600                         *arg = (unsigned long)f;
 601                         return 0;
 602                 }
 603         }
 604
 605         /* No session found. Create new one. */
 606
 607         err = -ENOBUFS;
 608         s = kzalloc(sizeof(struct rsvp_session), GFP_KERNEL);
 609         if (s == NULL)
 610                 goto errout;
 611         memcpy(s->dst, dst, sizeof(s->dst));
 612
 613         if (pinfo) {
 614                 s->dpi = pinfo->dpi;
 615                 s->protocol = pinfo->protocol;
 616                 s->tunnelid = pinfo->tunnelid;
 617         }
 618         sp = &data->ht[h1];
 619         for (nsp = rtnl_dereference(*sp); nsp;
 620              sp = &nsp->next, nsp = rtnl_dereference(*sp)) {
 621                 if ((nsp->dpi.mask & s->dpi.mask) != s->dpi.mask)
 622                         break;
 623         }
 624         RCU_INIT_POINTER(s->next, nsp);
 625         rcu_assign_pointer(*sp, s);
 626
 627         goto insert;
 628
 629 errout:
 630         kfree(f);
 631 errout2:
 632         tcf_exts_destroy(&e);
 633         return err;
 634 }
 635
 636 static void rsvp_walk(struct tcf_proto *tp, struct tcf_walker *arg)
 637 {
 638         struct rsvp_head *head = rtnl_dereference(tp->root);
 639         unsigned int h, h1;
 640
 641         if (arg->stop)
 642                 return;
 643
 644         for (h = 0; h < 256; h++) {
 645                 struct rsvp_session *s;
 646
 647                 for (s = rtnl_dereference(head->ht[h]); s;
 648                      s = rtnl_dereference(s->next)) {
 649                         for (h1 = 0; h1 <= 16; h1++) {
 650                                 struct rsvp_filter *f;
 651
 652                                 for (f = rtnl_dereference(s->ht[h1]); f;
 653                                      f = rtnl_dereference(f->next)) {
 654                                         if (arg->count < arg->skip) {
 655                                                 arg->count++;
 656                                                 continue;
 657                                         }
 658                                         if (arg->fn(tp, (unsigned long)f, arg) < 0) {
 659                                                 arg->stop = 1;
 660                                                 return;
 661                                         }
 662                                         arg->count++;
 663                                 }
 664                         }
 665                 }
 666         }
 667 }
 668
 669 static int rsvp_dump(struct net *net, struct tcf_proto *tp, unsigned long fh,
 670                      struct sk_buff *skb, struct tcmsg *t)
 671 {
 672         struct rsvp_filter *f = (struct rsvp_filter *)fh;
 673         struct rsvp_session *s;
 674         struct nlattr *nest;
 675         struct tc_rsvp_pinfo pinfo;
 676
 677         if (f == NULL)
 678                 return skb->len;
 679         s = f->sess;
 680
 681         t->tcm_handle = f->handle;
 682
 683         nest = nla_nest_start(skb, TCA_OPTIONS);
 684         if (nest == NULL)
 685                 goto nla_put_failure;
 686
 687         if (nla_put(skb, TCA_RSVP_DST, sizeof(s->dst), &s->dst))
 688                 goto nla_put_failure;
 689         pinfo.dpi = s->dpi;
 690         pinfo.spi = f->spi;
 691         pinfo.protocol = s->protocol;
 692         pinfo.tunnelid = s->tunnelid;
 693         pinfo.tunnelhdr = f->tunnelhdr;
 694         pinfo.pad = 0;
 695         if (nla_put(skb, TCA_RSVP_PINFO, sizeof(pinfo), &pinfo))
 696                 goto nla_put_failure;
 697         if (f->res.classid &&
 698             nla_put_u32(skb, TCA_RSVP_CLASSID, f->res.classid))
 699                 goto nla_put_failure;
 700         if (((f->handle >> 8) & 0xFF) != 16 &&
 701             nla_put(skb, TCA_RSVP_SRC, sizeof(f->src), f->src))
 702                 goto nla_put_failure;
 703
 704         if (tcf_exts_dump(skb, &f->exts) < 0)
 705                 goto nla_put_failure;
 706
 707         nla_nest_end(skb, nest);
 708
 709         if (tcf_exts_dump_stats(skb, &f->exts) < 0)
 710                 goto nla_put_failure;
 711         return skb->len;
 712
 713 nla_put_failure:
 714         nla_nest_cancel(skb, nest);
 715         return -1;
 716 }
 717
 718 static struct tcf_proto_ops RSVP_OPS __read_mostly = {
 719         .kind           =       RSVP_ID,
 720         .classify       =       rsvp_classify,
 721         .init           =       rsvp_init,
 722         .destroy        =       rsvp_destroy,
 723         .get            =       rsvp_get,
 724         .change         =       rsvp_change,
 725         .delete         =       rsvp_delete,
 726         .walk           =       rsvp_walk,
 727         .dump           =       rsvp_dump,
 728         .owner          =       THIS_MODULE,
 729 };
 730
 731 static int __init init_rsvp(void)
 732 {
 733         return register_tcf_proto_ops(&RSVP_OPS);
 734 }
 735
 736 static void __exit exit_rsvp(void)
 737 {
 738         unregister_tcf_proto_ops(&RSVP_OPS);
 739 }
 740
 741 module_init(init_rsvp)
 742 module_exit(exit_rsvp)