net/sched/cls_flow.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * net/sched/cls_flow.c         Generic flow classifier
   4  *
   5  * Copyright (c) 2007, 2008 Patrick McHardy <kaber@trash.net>
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10 #include <linux/list.h>
  11 #include <linux/jhash.h>
  12 #include <linux/random.h>
  13 #include <linux/pkt_cls.h>
  14 #include <linux/skbuff.h>
  15 #include <linux/in.h>
  16 #include <linux/ip.h>
  17 #include <linux/ipv6.h>
  18 #include <linux/if_vlan.h>
  19 #include <linux/slab.h>
  20 #include <linux/module.h>
  21 #include <net/inet_sock.h>
  22
  23 #include <net/pkt_cls.h>
  24 #include <net/ip.h>
  25 #include <net/route.h>
  26 #include <net/flow_dissector.h>
  27 #include <net/tc_wrapper.h>
  28
  29 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
  30 #include <net/netfilter/nf_conntrack.h>
  31 #endif
  32
  33 struct flow_head {
  34         struct list_head        filters;
  35         struct rcu_head         rcu;
  36 };
  37
  38 struct flow_filter {
  39         struct list_head        list;
  40         struct tcf_exts         exts;
  41         struct tcf_ematch_tree  ematches;
  42         struct tcf_proto        *tp;
  43         struct timer_list       perturb_timer;
  44         u32                     perturb_period;
  45         u32                     handle;
  46
  47         u32                     nkeys;
  48         u32                     keymask;
  49         u32                     mode;
  50         u32                     mask;
  51         u32                     xor;
  52         u32                     rshift;
  53         u32                     addend;
  54         u32                     divisor;
  55         u32                     baseclass;
  56         u32                     hashrnd;
  57         struct rcu_work         rwork;
  58 };
  59
  60 static inline u32 addr_fold(void *addr)
  61 {
  62         unsigned long a = (unsigned long)addr;
  63
  64         return (a & 0xFFFFFFFF) ^ (BITS_PER_LONG > 32 ? a >> 32 : 0);
  65 }
  66
  67 static u32 flow_get_src(const struct sk_buff *skb, const struct flow_keys *flow)
  68 {
  69         __be32 src = flow_get_u32_src(flow);
  70
  71         if (src)
  72                 return ntohl(src);
  73
  74         return addr_fold(skb->sk);
  75 }
  76
  77 static u32 flow_get_dst(const struct sk_buff *skb, const struct flow_keys *flow)
  78 {
  79         __be32 dst = flow_get_u32_dst(flow);
  80
  81         if (dst)
  82                 return ntohl(dst);
  83
  84         return addr_fold(skb_dst(skb)) ^ (__force u16)skb_protocol(skb, true);
  85 }
  86
  87 static u32 flow_get_proto(const struct sk_buff *skb,
  88                           const struct flow_keys *flow)
  89 {
  90         return flow->basic.ip_proto;
  91 }
  92
  93 static u32 flow_get_proto_src(const struct sk_buff *skb,
  94                               const struct flow_keys *flow)
  95 {
  96         if (flow->ports.ports)
  97                 return ntohs(flow->ports.src);
  98
  99         return addr_fold(skb->sk);
 100 }
 101
 102 static u32 flow_get_proto_dst(const struct sk_buff *skb,
 103                               const struct flow_keys *flow)
 104 {
 105         if (flow->ports.ports)
 106                 return ntohs(flow->ports.dst);
 107
 108         return addr_fold(skb_dst(skb)) ^ (__force u16)skb_protocol(skb, true);
 109 }
 110
 111 static u32 flow_get_iif(const struct sk_buff *skb)
 112 {
 113         return skb->skb_iif;
 114 }
 115
 116 static u32 flow_get_priority(const struct sk_buff *skb)
 117 {
 118         return skb->priority;
 119 }
 120
 121 static u32 flow_get_mark(const struct sk_buff *skb)
 122 {
 123         return skb->mark;
 124 }
 125
 126 static u32 flow_get_nfct(const struct sk_buff *skb)
 127 {
 128 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 129         return addr_fold(skb_nfct(skb));
 130 #else
 131         return 0;
 132 #endif
 133 }
 134
 135 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 136 #define CTTUPLE(skb, member)                                            \
 137 ({                                                                      \
 138         enum ip_conntrack_info ctinfo;                                  \
 139         const struct nf_conn *ct = nf_ct_get(skb, &ctinfo);             \
 140         if (ct == NULL)                                                 \
 141                 goto fallback;                                          \
 142         ct->tuplehash[CTINFO2DIR(ctinfo)].tuple.member;                 \
 143 })
 144 #else
 145 #define CTTUPLE(skb, member)                                            \
 146 ({                                                                      \
 147         goto fallback;                                                  \
 148         0;                                                              \
 149 })
 150 #endif
 151
 152 static u32 flow_get_nfct_src(const struct sk_buff *skb,
 153                              const struct flow_keys *flow)
 154 {
 155         switch (skb_protocol(skb, true)) {
 156         case htons(ETH_P_IP):
 157                 return ntohl(CTTUPLE(skb, src.u3.ip));
 158         case htons(ETH_P_IPV6):
 159                 return ntohl(CTTUPLE(skb, src.u3.ip6[3]));
 160         }
 161 fallback:
 162         return flow_get_src(skb, flow);
 163 }
 164
 165 static u32 flow_get_nfct_dst(const struct sk_buff *skb,
 166                              const struct flow_keys *flow)
 167 {
 168         switch (skb_protocol(skb, true)) {
 169         case htons(ETH_P_IP):
 170                 return ntohl(CTTUPLE(skb, dst.u3.ip));
 171         case htons(ETH_P_IPV6):
 172                 return ntohl(CTTUPLE(skb, dst.u3.ip6[3]));
 173         }
 174 fallback:
 175         return flow_get_dst(skb, flow);
 176 }
 177
 178 static u32 flow_get_nfct_proto_src(const struct sk_buff *skb,
 179                                    const struct flow_keys *flow)
 180 {
 181         return ntohs(CTTUPLE(skb, src.u.all));
 182 fallback:
 183         return flow_get_proto_src(skb, flow);
 184 }
 185
 186 static u32 flow_get_nfct_proto_dst(const struct sk_buff *skb,
 187                                    const struct flow_keys *flow)
 188 {
 189         return ntohs(CTTUPLE(skb, dst.u.all));
 190 fallback:
 191         return flow_get_proto_dst(skb, flow);
 192 }
 193
 194 static u32 flow_get_rtclassid(const struct sk_buff *skb)
 195 {
 196 #ifdef CONFIG_IP_ROUTE_CLASSID
 197         if (skb_dst(skb))
 198                 return skb_dst(skb)->tclassid;
 199 #endif
 200         return 0;
 201 }
 202
 203 static u32 flow_get_skuid(const struct sk_buff *skb)
 204 {
 205         struct sock *sk = skb_to_full_sk(skb);
 206
 207         if (sk && sk->sk_socket && sk->sk_socket->file) {
 208                 kuid_t skuid = sk->sk_socket->file->f_cred->fsuid;
 209
 210                 return from_kuid(&init_user_ns, skuid);
 211         }
 212         return 0;
 213 }
 214
 215 static u32 flow_get_skgid(const struct sk_buff *skb)
 216 {
 217         struct sock *sk = skb_to_full_sk(skb);
 218
 219         if (sk && sk->sk_socket && sk->sk_socket->file) {
 220                 kgid_t skgid = sk->sk_socket->file->f_cred->fsgid;
 221
 222                 return from_kgid(&init_user_ns, skgid);
 223         }
 224         return 0;
 225 }
 226
 227 static u32 flow_get_vlan_tag(const struct sk_buff *skb)
 228 {
 229         u16 tag;
 230
 231         if (vlan_get_tag(skb, &tag) < 0)
 232                 return 0;
 233         return tag & VLAN_VID_MASK;
 234 }
 235
 236 static u32 flow_get_rxhash(struct sk_buff *skb)
 237 {
 238         return skb_get_hash(skb);
 239 }
 240
 241 static u32 flow_key_get(struct sk_buff *skb, int key, struct flow_keys *flow)
 242 {
 243         switch (key) {
 244         case FLOW_KEY_SRC:
 245                 return flow_get_src(skb, flow);
 246         case FLOW_KEY_DST:
 247                 return flow_get_dst(skb, flow);
 248         case FLOW_KEY_PROTO:
 249                 return flow_get_proto(skb, flow);
 250         case FLOW_KEY_PROTO_SRC:
 251                 return flow_get_proto_src(skb, flow);
 252         case FLOW_KEY_PROTO_DST:
 253                 return flow_get_proto_dst(skb, flow);
 254         case FLOW_KEY_IIF:
 255                 return flow_get_iif(skb);
 256         case FLOW_KEY_PRIORITY:
 257                 return flow_get_priority(skb);
 258         case FLOW_KEY_MARK:
 259                 return flow_get_mark(skb);
 260         case FLOW_KEY_NFCT:
 261                 return flow_get_nfct(skb);
 262         case FLOW_KEY_NFCT_SRC:
 263                 return flow_get_nfct_src(skb, flow);
 264         case FLOW_KEY_NFCT_DST:
 265                 return flow_get_nfct_dst(skb, flow);
 266         case FLOW_KEY_NFCT_PROTO_SRC:
 267                 return flow_get_nfct_proto_src(skb, flow);
 268         case FLOW_KEY_NFCT_PROTO_DST:
 269                 return flow_get_nfct_proto_dst(skb, flow);
 270         case FLOW_KEY_RTCLASSID:
 271                 return flow_get_rtclassid(skb);
 272         case FLOW_KEY_SKUID:
 273                 return flow_get_skuid(skb);
 274         case FLOW_KEY_SKGID:
 275                 return flow_get_skgid(skb);
 276         case FLOW_KEY_VLAN_TAG:
 277                 return flow_get_vlan_tag(skb);
 278         case FLOW_KEY_RXHASH:
 279                 return flow_get_rxhash(skb);
 280         default:
 281                 WARN_ON(1);
 282                 return 0;
 283         }
 284 }
 285
 286 #define FLOW_KEYS_NEEDED ((1 << FLOW_KEY_SRC) |                 \
 287                           (1 << FLOW_KEY_DST) |                 \
 288                           (1 << FLOW_KEY_PROTO) |               \
 289                           (1 << FLOW_KEY_PROTO_SRC) |           \
 290                           (1 << FLOW_KEY_PROTO_DST) |           \
 291                           (1 << FLOW_KEY_NFCT_SRC) |            \
 292                           (1 << FLOW_KEY_NFCT_DST) |            \
 293                           (1 << FLOW_KEY_NFCT_PROTO_SRC) |      \
 294                           (1 << FLOW_KEY_NFCT_PROTO_DST))
 295
 296 TC_INDIRECT_SCOPE int flow_classify(struct sk_buff *skb,
 297                                     const struct tcf_proto *tp,
 298                                     struct tcf_result *res)
 299 {
 300         struct flow_head *head = rcu_dereference_bh(tp->root);
 301         struct flow_filter *f;
 302         u32 keymask;
 303         u32 classid;
 304         unsigned int n, key;
 305         int r;
 306
 307         list_for_each_entry_rcu(f, &head->filters, list) {
 308                 u32 keys[FLOW_KEY_MAX + 1];
 309                 struct flow_keys flow_keys;
 310
 311                 if (!tcf_em_tree_match(skb, &f->ematches, NULL))
 312                         continue;
 313
 314                 keymask = f->keymask;
 315                 if (keymask & FLOW_KEYS_NEEDED)
 316                         skb_flow_dissect_flow_keys(skb, &flow_keys, 0);
 317
 318                 for (n = 0; n < f->nkeys; n++) {
 319                         key = ffs(keymask) - 1;
 320                         keymask &= ~(1 << key);
 321                         keys[n] = flow_key_get(skb, key, &flow_keys);
 322                 }
 323
 324                 if (f->mode == FLOW_MODE_HASH)
 325                         classid = jhash2(keys, f->nkeys, f->hashrnd);
 326                 else {
 327                         classid = keys[0];
 328                         classid = (classid & f->mask) ^ f->xor;
 329                         classid = (classid >> f->rshift) + f->addend;
 330                 }
 331
 332                 if (f->divisor)
 333                         classid %= f->divisor;
 334
 335                 res->class   = 0;
 336                 res->classid = TC_H_MAKE(f->baseclass, f->baseclass + classid);
 337
 338                 r = tcf_exts_exec(skb, &f->exts, res);
 339                 if (r < 0)
 340                         continue;
 341                 return r;
 342         }
 343         return -1;
 344 }
 345
 346 static void flow_perturbation(struct timer_list *t)
 347 {
 348         struct flow_filter *f = from_timer(f, t, perturb_timer);
 349
 350         get_random_bytes(&f->hashrnd, 4);
 351         if (f->perturb_period)
 352                 mod_timer(&f->perturb_timer, jiffies + f->perturb_period);
 353 }
 354
 355 static const struct nla_policy flow_policy[TCA_FLOW_MAX + 1] = {
 356         [TCA_FLOW_KEYS]         = { .type = NLA_U32 },
 357         [TCA_FLOW_MODE]         = { .type = NLA_U32 },
 358         [TCA_FLOW_BASECLASS]    = { .type = NLA_U32 },
 359         [TCA_FLOW_RSHIFT]       = { .type = NLA_U32 },
 360         [TCA_FLOW_ADDEND]       = { .type = NLA_U32 },
 361         [TCA_FLOW_MASK]         = { .type = NLA_U32 },
 362         [TCA_FLOW_XOR]          = { .type = NLA_U32 },
 363         [TCA_FLOW_DIVISOR]      = { .type = NLA_U32 },
 364         [TCA_FLOW_ACT]          = { .type = NLA_NESTED },
 365         [TCA_FLOW_POLICE]       = { .type = NLA_NESTED },
 366         [TCA_FLOW_EMATCHES]     = { .type = NLA_NESTED },
 367         [TCA_FLOW_PERTURB]      = { .type = NLA_U32 },
 368 };
 369
 370 static void __flow_destroy_filter(struct flow_filter *f)
 371 {
 372         timer_shutdown_sync(&f->perturb_timer);
 373         tcf_exts_destroy(&f->exts);
 374         tcf_em_tree_destroy(&f->ematches);
 375         tcf_exts_put_net(&f->exts);
 376         kfree(f);
 377 }
 378
 379 static void flow_destroy_filter_work(struct work_struct *work)
 380 {
 381         struct flow_filter *f = container_of(to_rcu_work(work),
 382                                              struct flow_filter,
 383                                              rwork);
 384         rtnl_lock();
 385         __flow_destroy_filter(f);
 386         rtnl_unlock();
 387 }
 388
 389 static int flow_change(struct net *net, struct sk_buff *in_skb,
 390                        struct tcf_proto *tp, unsigned long base,
 391                        u32 handle, struct nlattr **tca,
 392                        void **arg, u32 flags,
 393                        struct netlink_ext_ack *extack)
 394 {
 395         struct flow_head *head = rtnl_dereference(tp->root);
 396         struct flow_filter *fold, *fnew;
 397         struct nlattr *opt = tca[TCA_OPTIONS];
 398         struct nlattr *tb[TCA_FLOW_MAX + 1];
 399         unsigned int nkeys = 0;
 400         unsigned int perturb_period = 0;
 401         u32 baseclass = 0;
 402         u32 keymask = 0;
 403         u32 mode;
 404         int err;
 405
 406         if (opt == NULL)
 407                 return -EINVAL;
 408
 409         err = nla_parse_nested_deprecated(tb, TCA_FLOW_MAX, opt, flow_policy,
 410                                           NULL);
 411         if (err < 0)
 412                 return err;
 413
 414         if (tb[TCA_FLOW_BASECLASS]) {
 415                 baseclass = nla_get_u32(tb[TCA_FLOW_BASECLASS]);
 416                 if (TC_H_MIN(baseclass) == 0)
 417                         return -EINVAL;
 418         }
 419
 420         if (tb[TCA_FLOW_KEYS]) {
 421                 keymask = nla_get_u32(tb[TCA_FLOW_KEYS]);
 422
 423                 nkeys = hweight32(keymask);
 424                 if (nkeys == 0)
 425                         return -EINVAL;
 426
 427                 if (fls(keymask) - 1 > FLOW_KEY_MAX)
 428                         return -EOPNOTSUPP;
 429
 430                 if ((keymask & (FLOW_KEY_SKUID|FLOW_KEY_SKGID)) &&
 431                     sk_user_ns(NETLINK_CB(in_skb).sk) != &init_user_ns)
 432                         return -EOPNOTSUPP;
 433         }
 434
 435         fnew = kzalloc(sizeof(*fnew), GFP_KERNEL);
 436         if (!fnew)
 437                 return -ENOBUFS;
 438
 439         err = tcf_em_tree_validate(tp, tb[TCA_FLOW_EMATCHES], &fnew->ematches);
 440         if (err < 0)
 441                 goto err1;
 442
 443         err = tcf_exts_init(&fnew->exts, net, TCA_FLOW_ACT, TCA_FLOW_POLICE);
 444         if (err < 0)
 445                 goto err2;
 446
 447         err = tcf_exts_validate(net, tp, tb, tca[TCA_RATE], &fnew->exts, flags,
 448                                 extack);
 449         if (err < 0)
 450                 goto err2;
 451
 452         fold = *arg;
 453         if (fold) {
 454                 err = -EINVAL;
 455                 if (fold->handle != handle && handle)
 456                         goto err2;
 457
 458                 /* Copy fold into fnew */
 459                 fnew->tp = fold->tp;
 460                 fnew->handle = fold->handle;
 461                 fnew->nkeys = fold->nkeys;
 462                 fnew->keymask = fold->keymask;
 463                 fnew->mode = fold->mode;
 464                 fnew->mask = fold->mask;
 465                 fnew->xor = fold->xor;
 466                 fnew->rshift = fold->rshift;
 467                 fnew->addend = fold->addend;
 468                 fnew->divisor = fold->divisor;
 469                 fnew->baseclass = fold->baseclass;
 470                 fnew->hashrnd = fold->hashrnd;
 471
 472                 mode = fold->mode;
 473                 if (tb[TCA_FLOW_MODE])
 474                         mode = nla_get_u32(tb[TCA_FLOW_MODE]);
 475                 if (mode != FLOW_MODE_HASH && nkeys > 1)
 476                         goto err2;
 477
 478                 if (mode == FLOW_MODE_HASH)
 479                         perturb_period = fold->perturb_period;
 480                 if (tb[TCA_FLOW_PERTURB]) {
 481                         if (mode != FLOW_MODE_HASH)
 482                                 goto err2;
 483                         perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ;
 484                 }
 485         } else {
 486                 err = -EINVAL;
 487                 if (!handle)
 488                         goto err2;
 489                 if (!tb[TCA_FLOW_KEYS])
 490                         goto err2;
 491
 492                 mode = FLOW_MODE_MAP;
 493                 if (tb[TCA_FLOW_MODE])
 494                         mode = nla_get_u32(tb[TCA_FLOW_MODE]);
 495                 if (mode != FLOW_MODE_HASH && nkeys > 1)
 496                         goto err2;
 497
 498                 if (tb[TCA_FLOW_PERTURB]) {
 499                         if (mode != FLOW_MODE_HASH)
 500                                 goto err2;
 501                         perturb_period = nla_get_u32(tb[TCA_FLOW_PERTURB]) * HZ;
 502                 }
 503
 504                 if (TC_H_MAJ(baseclass) == 0) {
 505                         struct Qdisc *q = tcf_block_q(tp->chain->block);
 506
 507                         baseclass = TC_H_MAKE(q->handle, baseclass);
 508                 }
 509                 if (TC_H_MIN(baseclass) == 0)
 510                         baseclass = TC_H_MAKE(baseclass, 1);
 511
 512                 fnew->handle = handle;
 513                 fnew->mask  = ~0U;
 514                 fnew->tp = tp;
 515                 get_random_bytes(&fnew->hashrnd, 4);
 516         }
 517
 518         timer_setup(&fnew->perturb_timer, flow_perturbation, TIMER_DEFERRABLE);
 519
 520         tcf_block_netif_keep_dst(tp->chain->block);
 521
 522         if (tb[TCA_FLOW_KEYS]) {
 523                 fnew->keymask = keymask;
 524                 fnew->nkeys   = nkeys;
 525         }
 526
 527         fnew->mode = mode;
 528
 529         if (tb[TCA_FLOW_MASK])
 530                 fnew->mask = nla_get_u32(tb[TCA_FLOW_MASK]);
 531         if (tb[TCA_FLOW_XOR])
 532                 fnew->xor = nla_get_u32(tb[TCA_FLOW_XOR]);
 533         if (tb[TCA_FLOW_RSHIFT])
 534                 fnew->rshift = nla_get_u32(tb[TCA_FLOW_RSHIFT]);
 535         if (tb[TCA_FLOW_ADDEND])
 536                 fnew->addend = nla_get_u32(tb[TCA_FLOW_ADDEND]);
 537
 538         if (tb[TCA_FLOW_DIVISOR])
 539                 fnew->divisor = nla_get_u32(tb[TCA_FLOW_DIVISOR]);
 540         if (baseclass)
 541                 fnew->baseclass = baseclass;
 542
 543         fnew->perturb_period = perturb_period;
 544         if (perturb_period)
 545                 mod_timer(&fnew->perturb_timer, jiffies + perturb_period);
 546
 547         if (!*arg)
 548                 list_add_tail_rcu(&fnew->list, &head->filters);
 549         else
 550                 list_replace_rcu(&fold->list, &fnew->list);
 551
 552         *arg = fnew;
 553
 554         if (fold) {
 555                 tcf_exts_get_net(&fold->exts);
 556                 tcf_queue_work(&fold->rwork, flow_destroy_filter_work);
 557         }
 558         return 0;
 559
 560 err2:
 561         tcf_exts_destroy(&fnew->exts);
 562         tcf_em_tree_destroy(&fnew->ematches);
 563 err1:
 564         kfree(fnew);
 565         return err;
 566 }
 567
 568 static int flow_delete(struct tcf_proto *tp, void *arg, bool *last,
 569                        bool rtnl_held, struct netlink_ext_ack *extack)
 570 {
 571         struct flow_head *head = rtnl_dereference(tp->root);
 572         struct flow_filter *f = arg;
 573
 574         list_del_rcu(&f->list);
 575         tcf_exts_get_net(&f->exts);
 576         tcf_queue_work(&f->rwork, flow_destroy_filter_work);
 577         *last = list_empty(&head->filters);
 578         return 0;
 579 }
 580
 581 static int flow_init(struct tcf_proto *tp)
 582 {
 583         struct flow_head *head;
 584
 585         head = kzalloc(sizeof(*head), GFP_KERNEL);
 586         if (head == NULL)
 587                 return -ENOBUFS;
 588         INIT_LIST_HEAD(&head->filters);
 589         rcu_assign_pointer(tp->root, head);
 590         return 0;
 591 }
 592
 593 static void flow_destroy(struct tcf_proto *tp, bool rtnl_held,
 594                          struct netlink_ext_ack *extack)
 595 {
 596         struct flow_head *head = rtnl_dereference(tp->root);
 597         struct flow_filter *f, *next;
 598
 599         list_for_each_entry_safe(f, next, &head->filters, list) {
 600                 list_del_rcu(&f->list);
 601                 if (tcf_exts_get_net(&f->exts))
 602                         tcf_queue_work(&f->rwork, flow_destroy_filter_work);
 603                 else
 604                         __flow_destroy_filter(f);
 605         }
 606         kfree_rcu(head, rcu);
 607 }
 608
 609 static void *flow_get(struct tcf_proto *tp, u32 handle)
 610 {
 611         struct flow_head *head = rtnl_dereference(tp->root);
 612         struct flow_filter *f;
 613
 614         list_for_each_entry(f, &head->filters, list)
 615                 if (f->handle == handle)
 616                         return f;
 617         return NULL;
 618 }
 619
 620 static int flow_dump(struct net *net, struct tcf_proto *tp, void *fh,
 621                      struct sk_buff *skb, struct tcmsg *t, bool rtnl_held)
 622 {
 623         struct flow_filter *f = fh;
 624         struct nlattr *nest;
 625
 626         if (f == NULL)
 627                 return skb->len;
 628
 629         t->tcm_handle = f->handle;
 630
 631         nest = nla_nest_start_noflag(skb, TCA_OPTIONS);
 632         if (nest == NULL)
 633                 goto nla_put_failure;
 634
 635         if (nla_put_u32(skb, TCA_FLOW_KEYS, f->keymask) ||
 636             nla_put_u32(skb, TCA_FLOW_MODE, f->mode))
 637                 goto nla_put_failure;
 638
 639         if (f->mask != ~0 || f->xor != 0) {
 640                 if (nla_put_u32(skb, TCA_FLOW_MASK, f->mask) ||
 641                     nla_put_u32(skb, TCA_FLOW_XOR, f->xor))
 642                         goto nla_put_failure;
 643         }
 644         if (f->rshift &&
 645             nla_put_u32(skb, TCA_FLOW_RSHIFT, f->rshift))
 646                 goto nla_put_failure;
 647         if (f->addend &&
 648             nla_put_u32(skb, TCA_FLOW_ADDEND, f->addend))
 649                 goto nla_put_failure;
 650
 651         if (f->divisor &&
 652             nla_put_u32(skb, TCA_FLOW_DIVISOR, f->divisor))
 653                 goto nla_put_failure;
 654         if (f->baseclass &&
 655             nla_put_u32(skb, TCA_FLOW_BASECLASS, f->baseclass))
 656                 goto nla_put_failure;
 657
 658         if (f->perturb_period &&
 659             nla_put_u32(skb, TCA_FLOW_PERTURB, f->perturb_period / HZ))
 660                 goto nla_put_failure;
 661
 662         if (tcf_exts_dump(skb, &f->exts) < 0)
 663                 goto nla_put_failure;
 664 #ifdef CONFIG_NET_EMATCH
 665         if (f->ematches.hdr.nmatches &&
 666             tcf_em_tree_dump(skb, &f->ematches, TCA_FLOW_EMATCHES) < 0)
 667                 goto nla_put_failure;
 668 #endif
 669         nla_nest_end(skb, nest);
 670
 671         if (tcf_exts_dump_stats(skb, &f->exts) < 0)
 672                 goto nla_put_failure;
 673
 674         return skb->len;
 675
 676 nla_put_failure:
 677         nla_nest_cancel(skb, nest);
 678         return -1;
 679 }
 680
 681 static void flow_walk(struct tcf_proto *tp, struct tcf_walker *arg,
 682                       bool rtnl_held)
 683 {
 684         struct flow_head *head = rtnl_dereference(tp->root);
 685         struct flow_filter *f;
 686
 687         list_for_each_entry(f, &head->filters, list) {
 688                 if (!tc_cls_stats_dump(tp, arg, f))
 689                         break;
 690         }
 691 }
 692
 693 static struct tcf_proto_ops cls_flow_ops __read_mostly = {
 694         .kind           = "flow",
 695         .classify       = flow_classify,
 696         .init           = flow_init,
 697         .destroy        = flow_destroy,
 698         .change         = flow_change,
 699         .delete         = flow_delete,
 700         .get            = flow_get,
 701         .dump           = flow_dump,
 702         .walk           = flow_walk,
 703         .owner          = THIS_MODULE,
 704 };
 705
 706 static int __init cls_flow_init(void)
 707 {
 708         return register_tcf_proto_ops(&cls_flow_ops);
 709 }
 710
 711 static void __exit cls_flow_exit(void)
 712 {
 713         unregister_tcf_proto_ops(&cls_flow_ops);
 714 }
 715
 716 module_init(cls_flow_init);
 717 module_exit(cls_flow_exit);
 718
 719 MODULE_LICENSE("GPL");
 720 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
 721 MODULE_DESCRIPTION("TC flow classifier");