net/netfilter/nf_flow_table_core.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 #include <linux/kernel.h>
   3 #include <linux/init.h>
   4 #include <linux/module.h>
   5 #include <linux/netfilter.h>
   6 #include <linux/rhashtable.h>
   7 #include <linux/netdevice.h>
   8 #include <net/ip.h>
   9 #include <net/ip6_route.h>
  10 #include <net/netfilter/nf_tables.h>
  11 #include <net/netfilter/nf_flow_table.h>
  12 #include <net/netfilter/nf_conntrack.h>
  13 #include <net/netfilter/nf_conntrack_core.h>
  14 #include <net/netfilter/nf_conntrack_l4proto.h>
  15 #include <net/netfilter/nf_conntrack_tuple.h>
  16
  17 static DEFINE_MUTEX(flowtable_lock);
  18 static LIST_HEAD(flowtables);
  19
  20 static void
  21 flow_offload_fill_dir(struct flow_offload *flow,
  22                       enum flow_offload_tuple_dir dir)
  23 {
  24         struct flow_offload_tuple *ft = &flow->tuplehash[dir].tuple;
  25         struct nf_conntrack_tuple *ctt = &flow->ct->tuplehash[dir].tuple;
  26
  27         ft->dir = dir;
  28
  29         switch (ctt->src.l3num) {
  30         case NFPROTO_IPV4:
  31                 ft->src_v4 = ctt->src.u3.in;
  32                 ft->dst_v4 = ctt->dst.u3.in;
  33                 break;
  34         case NFPROTO_IPV6:
  35                 ft->src_v6 = ctt->src.u3.in6;
  36                 ft->dst_v6 = ctt->dst.u3.in6;
  37                 break;
  38         }
  39
  40         ft->l3proto = ctt->src.l3num;
  41         ft->l4proto = ctt->dst.protonum;
  42         ft->src_port = ctt->src.u.tcp.port;
  43         ft->dst_port = ctt->dst.u.tcp.port;
  44 }
  45
  46 struct flow_offload *flow_offload_alloc(struct nf_conn *ct)
  47 {
  48         struct flow_offload *flow;
  49
  50         if (unlikely(nf_ct_is_dying(ct) ||
  51             !atomic_inc_not_zero(&ct->ct_general.use)))
  52                 return NULL;
  53
  54         flow = kzalloc(sizeof(*flow), GFP_ATOMIC);
  55         if (!flow)
  56                 goto err_ct_refcnt;
  57
  58         flow->ct = ct;
  59
  60         flow_offload_fill_dir(flow, FLOW_OFFLOAD_DIR_ORIGINAL);
  61         flow_offload_fill_dir(flow, FLOW_OFFLOAD_DIR_REPLY);
  62
  63         if (ct->status & IPS_SRC_NAT)
  64                 __set_bit(NF_FLOW_SNAT, &flow->flags);
  65         if (ct->status & IPS_DST_NAT)
  66                 __set_bit(NF_FLOW_DNAT, &flow->flags);
  67
  68         return flow;
  69
  70 err_ct_refcnt:
  71         nf_ct_put(ct);
  72
  73         return NULL;
  74 }
  75 EXPORT_SYMBOL_GPL(flow_offload_alloc);
  76
  77 static u32 flow_offload_dst_cookie(struct flow_offload_tuple *flow_tuple)
  78 {
  79         const struct rt6_info *rt;
  80
  81         if (flow_tuple->l3proto == NFPROTO_IPV6) {
  82                 rt = (const struct rt6_info *)flow_tuple->dst_cache;
  83                 return rt6_get_cookie(rt);
  84         }
  85
  86         return 0;
  87 }
  88
  89 static int flow_offload_fill_route(struct flow_offload *flow,
  90                                    const struct nf_flow_route *route,
  91                                    enum flow_offload_tuple_dir dir)
  92 {
  93         struct flow_offload_tuple *flow_tuple = &flow->tuplehash[dir].tuple;
  94         struct dst_entry *dst = route->tuple[dir].dst;
  95         int i, j = 0;
  96
  97         switch (flow_tuple->l3proto) {
  98         case NFPROTO_IPV4:
  99                 flow_tuple->mtu = ip_dst_mtu_maybe_forward(dst, true);
 100                 break;
 101         case NFPROTO_IPV6:
 102                 flow_tuple->mtu = ip6_dst_mtu_forward(dst);
 103                 break;
 104         }
 105
 106         flow_tuple->iifidx = route->tuple[dir].in.ifindex;
 107         for (i = route->tuple[dir].in.num_encaps - 1; i >= 0; i--) {
 108                 flow_tuple->encap[j].id = route->tuple[dir].in.encap[i].id;
 109                 flow_tuple->encap[j].proto = route->tuple[dir].in.encap[i].proto;
 110                 if (route->tuple[dir].in.ingress_vlans & BIT(i))
 111                         flow_tuple->in_vlan_ingress |= BIT(j);
 112                 j++;
 113         }
 114         flow_tuple->encap_num = route->tuple[dir].in.num_encaps;
 115
 116         switch (route->tuple[dir].xmit_type) {
 117         case FLOW_OFFLOAD_XMIT_DIRECT:
 118                 memcpy(flow_tuple->out.h_dest, route->tuple[dir].out.h_dest,
 119                        ETH_ALEN);
 120                 memcpy(flow_tuple->out.h_source, route->tuple[dir].out.h_source,
 121                        ETH_ALEN);
 122                 flow_tuple->out.ifidx = route->tuple[dir].out.ifindex;
 123                 flow_tuple->out.hw_ifidx = route->tuple[dir].out.hw_ifindex;
 124                 break;
 125         case FLOW_OFFLOAD_XMIT_XFRM:
 126         case FLOW_OFFLOAD_XMIT_NEIGH:
 127                 if (!dst_hold_safe(route->tuple[dir].dst))
 128                         return -1;
 129
 130                 flow_tuple->dst_cache = dst;
 131                 flow_tuple->dst_cookie = flow_offload_dst_cookie(flow_tuple);
 132                 break;
 133         default:
 134                 WARN_ON_ONCE(1);
 135                 break;
 136         }
 137         flow_tuple->xmit_type = route->tuple[dir].xmit_type;
 138
 139         return 0;
 140 }
 141
 142 static void nft_flow_dst_release(struct flow_offload *flow,
 143                                  enum flow_offload_tuple_dir dir)
 144 {
 145         if (flow->tuplehash[dir].tuple.xmit_type == FLOW_OFFLOAD_XMIT_NEIGH ||
 146             flow->tuplehash[dir].tuple.xmit_type == FLOW_OFFLOAD_XMIT_XFRM)
 147                 dst_release(flow->tuplehash[dir].tuple.dst_cache);
 148 }
 149
 150 int flow_offload_route_init(struct flow_offload *flow,
 151                             const struct nf_flow_route *route)
 152 {
 153         int err;
 154
 155         err = flow_offload_fill_route(flow, route, FLOW_OFFLOAD_DIR_ORIGINAL);
 156         if (err < 0)
 157                 return err;
 158
 159         err = flow_offload_fill_route(flow, route, FLOW_OFFLOAD_DIR_REPLY);
 160         if (err < 0)
 161                 goto err_route_reply;
 162
 163         flow->type = NF_FLOW_OFFLOAD_ROUTE;
 164
 165         return 0;
 166
 167 err_route_reply:
 168         nft_flow_dst_release(flow, FLOW_OFFLOAD_DIR_ORIGINAL);
 169
 170         return err;
 171 }
 172 EXPORT_SYMBOL_GPL(flow_offload_route_init);
 173
 174 static void flow_offload_fixup_tcp(struct ip_ct_tcp *tcp)
 175 {
 176         tcp->state = TCP_CONNTRACK_ESTABLISHED;
 177         tcp->seen[0].td_maxwin = 0;
 178         tcp->seen[1].td_maxwin = 0;
 179 }
 180
 181 static void flow_offload_fixup_ct_timeout(struct nf_conn *ct)
 182 {
 183         const struct nf_conntrack_l4proto *l4proto;
 184         struct net *net = nf_ct_net(ct);
 185         int l4num = nf_ct_protonum(ct);
 186         unsigned int timeout;
 187
 188         l4proto = nf_ct_l4proto_find(l4num);
 189         if (!l4proto)
 190                 return;
 191
 192         if (l4num == IPPROTO_TCP) {
 193                 struct nf_tcp_net *tn = nf_tcp_pernet(net);
 194
 195                 timeout = tn->offload_pickup;
 196         } else if (l4num == IPPROTO_UDP) {
 197                 struct nf_udp_net *tn = nf_udp_pernet(net);
 198
 199                 timeout = tn->offload_pickup;
 200         } else {
 201                 return;
 202         }
 203
 204         if (nf_flow_timeout_delta(ct->timeout) > (__s32)timeout)
 205                 ct->timeout = nfct_time_stamp + timeout;
 206 }
 207
 208 static void flow_offload_fixup_ct_state(struct nf_conn *ct)
 209 {
 210         if (nf_ct_protonum(ct) == IPPROTO_TCP)
 211                 flow_offload_fixup_tcp(&ct->proto.tcp);
 212 }
 213
 214 static void flow_offload_fixup_ct(struct nf_conn *ct)
 215 {
 216         flow_offload_fixup_ct_state(ct);
 217         flow_offload_fixup_ct_timeout(ct);
 218 }
 219
 220 static void flow_offload_route_release(struct flow_offload *flow)
 221 {
 222         nft_flow_dst_release(flow, FLOW_OFFLOAD_DIR_ORIGINAL);
 223         nft_flow_dst_release(flow, FLOW_OFFLOAD_DIR_REPLY);
 224 }
 225
 226 void flow_offload_free(struct flow_offload *flow)
 227 {
 228         switch (flow->type) {
 229         case NF_FLOW_OFFLOAD_ROUTE:
 230                 flow_offload_route_release(flow);
 231                 break;
 232         default:
 233                 break;
 234         }
 235         nf_ct_put(flow->ct);
 236         kfree_rcu(flow, rcu_head);
 237 }
 238 EXPORT_SYMBOL_GPL(flow_offload_free);
 239
 240 static u32 flow_offload_hash(const void *data, u32 len, u32 seed)
 241 {
 242         const struct flow_offload_tuple *tuple = data;
 243
 244         return jhash(tuple, offsetof(struct flow_offload_tuple, __hash), seed);
 245 }
 246
 247 static u32 flow_offload_hash_obj(const void *data, u32 len, u32 seed)
 248 {
 249         const struct flow_offload_tuple_rhash *tuplehash = data;
 250
 251         return jhash(&tuplehash->tuple, offsetof(struct flow_offload_tuple, __hash), seed);
 252 }
 253
 254 static int flow_offload_hash_cmp(struct rhashtable_compare_arg *arg,
 255                                         const void *ptr)
 256 {
 257         const struct flow_offload_tuple *tuple = arg->key;
 258         const struct flow_offload_tuple_rhash *x = ptr;
 259
 260         if (memcmp(&x->tuple, tuple, offsetof(struct flow_offload_tuple, __hash)))
 261                 return 1;
 262
 263         return 0;
 264 }
 265
 266 static const struct rhashtable_params nf_flow_offload_rhash_params = {
 267         .head_offset            = offsetof(struct flow_offload_tuple_rhash, node),
 268         .hashfn                 = flow_offload_hash,
 269         .obj_hashfn             = flow_offload_hash_obj,
 270         .obj_cmpfn              = flow_offload_hash_cmp,
 271         .automatic_shrinking    = true,
 272 };
 273
 274 unsigned long flow_offload_get_timeout(struct flow_offload *flow)
 275 {
 276         const struct nf_conntrack_l4proto *l4proto;
 277         unsigned long timeout = NF_FLOW_TIMEOUT;
 278         struct net *net = nf_ct_net(flow->ct);
 279         int l4num = nf_ct_protonum(flow->ct);
 280
 281         l4proto = nf_ct_l4proto_find(l4num);
 282         if (!l4proto)
 283                 return timeout;
 284
 285         if (l4num == IPPROTO_TCP) {
 286                 struct nf_tcp_net *tn = nf_tcp_pernet(net);
 287
 288                 timeout = tn->offload_timeout;
 289         } else if (l4num == IPPROTO_UDP) {
 290                 struct nf_udp_net *tn = nf_udp_pernet(net);
 291
 292                 timeout = tn->offload_timeout;
 293         }
 294
 295         return timeout;
 296 }
 297
 298 int flow_offload_add(struct nf_flowtable *flow_table, struct flow_offload *flow)
 299 {
 300         int err;
 301
 302         flow->timeout = nf_flowtable_time_stamp + flow_offload_get_timeout(flow);
 303
 304         err = rhashtable_insert_fast(&flow_table->rhashtable,
 305                                      &flow->tuplehash[0].node,
 306                                      nf_flow_offload_rhash_params);
 307         if (err < 0)
 308                 return err;
 309
 310         err = rhashtable_insert_fast(&flow_table->rhashtable,
 311                                      &flow->tuplehash[1].node,
 312                                      nf_flow_offload_rhash_params);
 313         if (err < 0) {
 314                 rhashtable_remove_fast(&flow_table->rhashtable,
 315                                        &flow->tuplehash[0].node,
 316                                        nf_flow_offload_rhash_params);
 317                 return err;
 318         }
 319
 320         nf_ct_offload_timeout(flow->ct);
 321
 322         if (nf_flowtable_hw_offload(flow_table)) {
 323                 __set_bit(NF_FLOW_HW, &flow->flags);
 324                 nf_flow_offload_add(flow_table, flow);
 325         }
 326
 327         return 0;
 328 }
 329 EXPORT_SYMBOL_GPL(flow_offload_add);
 330
 331 void flow_offload_refresh(struct nf_flowtable *flow_table,
 332                           struct flow_offload *flow)
 333 {
 334         flow->timeout = nf_flowtable_time_stamp + flow_offload_get_timeout(flow);
 335
 336         if (likely(!nf_flowtable_hw_offload(flow_table)))
 337                 return;
 338
 339         nf_flow_offload_add(flow_table, flow);
 340 }
 341 EXPORT_SYMBOL_GPL(flow_offload_refresh);
 342
 343 static inline bool nf_flow_has_expired(const struct flow_offload *flow)
 344 {
 345         return nf_flow_timeout_delta(flow->timeout) <= 0;
 346 }
 347
 348 static void flow_offload_del(struct nf_flowtable *flow_table,
 349                              struct flow_offload *flow)
 350 {
 351         rhashtable_remove_fast(&flow_table->rhashtable,
 352                                &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].node,
 353                                nf_flow_offload_rhash_params);
 354         rhashtable_remove_fast(&flow_table->rhashtable,
 355                                &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].node,
 356                                nf_flow_offload_rhash_params);
 357
 358         clear_bit(IPS_OFFLOAD_BIT, &flow->ct->status);
 359
 360         if (nf_flow_has_expired(flow))
 361                 flow_offload_fixup_ct(flow->ct);
 362         else
 363                 flow_offload_fixup_ct_timeout(flow->ct);
 364
 365         flow_offload_free(flow);
 366 }
 367
 368 void flow_offload_teardown(struct flow_offload *flow)
 369 {
 370         set_bit(NF_FLOW_TEARDOWN, &flow->flags);
 371
 372         flow_offload_fixup_ct_state(flow->ct);
 373 }
 374 EXPORT_SYMBOL_GPL(flow_offload_teardown);
 375
 376 struct flow_offload_tuple_rhash *
 377 flow_offload_lookup(struct nf_flowtable *flow_table,
 378                     struct flow_offload_tuple *tuple)
 379 {
 380         struct flow_offload_tuple_rhash *tuplehash;
 381         struct flow_offload *flow;
 382         int dir;
 383
 384         tuplehash = rhashtable_lookup(&flow_table->rhashtable, tuple,
 385                                       nf_flow_offload_rhash_params);
 386         if (!tuplehash)
 387                 return NULL;
 388
 389         dir = tuplehash->tuple.dir;
 390         flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
 391         if (test_bit(NF_FLOW_TEARDOWN, &flow->flags))
 392                 return NULL;
 393
 394         if (unlikely(nf_ct_is_dying(flow->ct)))
 395                 return NULL;
 396
 397         return tuplehash;
 398 }
 399 EXPORT_SYMBOL_GPL(flow_offload_lookup);
 400
 401 static int
 402 nf_flow_table_iterate(struct nf_flowtable *flow_table,
 403                       void (*iter)(struct flow_offload *flow, void *data),
 404                       void *data)
 405 {
 406         struct flow_offload_tuple_rhash *tuplehash;
 407         struct rhashtable_iter hti;
 408         struct flow_offload *flow;
 409         int err = 0;
 410
 411         rhashtable_walk_enter(&flow_table->rhashtable, &hti);
 412         rhashtable_walk_start(&hti);
 413
 414         while ((tuplehash = rhashtable_walk_next(&hti))) {
 415                 if (IS_ERR(tuplehash)) {
 416                         if (PTR_ERR(tuplehash) != -EAGAIN) {
 417                                 err = PTR_ERR(tuplehash);
 418                                 break;
 419                         }
 420                         continue;
 421                 }
 422                 if (tuplehash->tuple.dir)
 423                         continue;
 424
 425                 flow = container_of(tuplehash, struct flow_offload, tuplehash[0]);
 426
 427                 iter(flow, data);
 428         }
 429         rhashtable_walk_stop(&hti);
 430         rhashtable_walk_exit(&hti);
 431
 432         return err;
 433 }
 434
 435 static bool flow_offload_stale_dst(struct flow_offload_tuple *tuple)
 436 {
 437         struct dst_entry *dst;
 438
 439         if (tuple->xmit_type == FLOW_OFFLOAD_XMIT_NEIGH ||
 440             tuple->xmit_type == FLOW_OFFLOAD_XMIT_XFRM) {
 441                 dst = tuple->dst_cache;
 442                 if (!dst_check(dst, tuple->dst_cookie))
 443                         return true;
 444         }
 445
 446         return false;
 447 }
 448
 449 static bool nf_flow_has_stale_dst(struct flow_offload *flow)
 450 {
 451         return flow_offload_stale_dst(&flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple) ||
 452                flow_offload_stale_dst(&flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple);
 453 }
 454
 455 static void nf_flow_offload_gc_step(struct flow_offload *flow, void *data)
 456 {
 457         struct nf_flowtable *flow_table = data;
 458
 459         if (nf_flow_has_expired(flow) ||
 460             nf_ct_is_dying(flow->ct) ||
 461             nf_flow_has_stale_dst(flow))
 462                 set_bit(NF_FLOW_TEARDOWN, &flow->flags);
 463
 464         if (test_bit(NF_FLOW_TEARDOWN, &flow->flags)) {
 465                 if (test_bit(NF_FLOW_HW, &flow->flags)) {
 466                         if (!test_bit(NF_FLOW_HW_DYING, &flow->flags))
 467                                 nf_flow_offload_del(flow_table, flow);
 468                         else if (test_bit(NF_FLOW_HW_DEAD, &flow->flags))
 469                                 flow_offload_del(flow_table, flow);
 470                 } else {
 471                         flow_offload_del(flow_table, flow);
 472                 }
 473         } else if (test_bit(NF_FLOW_HW, &flow->flags)) {
 474                 nf_flow_offload_stats(flow_table, flow);
 475         }
 476 }
 477
 478 static void nf_flow_offload_work_gc(struct work_struct *work)
 479 {
 480         struct nf_flowtable *flow_table;
 481
 482         flow_table = container_of(work, struct nf_flowtable, gc_work.work);
 483         nf_flow_table_iterate(flow_table, nf_flow_offload_gc_step, flow_table);
 484         queue_delayed_work(system_power_efficient_wq, &flow_table->gc_work, HZ);
 485 }
 486
 487 static void nf_flow_nat_port_tcp(struct sk_buff *skb, unsigned int thoff,
 488                                  __be16 port, __be16 new_port)
 489 {
 490         struct tcphdr *tcph;
 491
 492         tcph = (void *)(skb_network_header(skb) + thoff);
 493         inet_proto_csum_replace2(&tcph->check, skb, port, new_port, false);
 494 }
 495
 496 static void nf_flow_nat_port_udp(struct sk_buff *skb, unsigned int thoff,
 497                                  __be16 port, __be16 new_port)
 498 {
 499         struct udphdr *udph;
 500
 501         udph = (void *)(skb_network_header(skb) + thoff);
 502         if (udph->check || skb->ip_summed == CHECKSUM_PARTIAL) {
 503                 inet_proto_csum_replace2(&udph->check, skb, port,
 504                                          new_port, false);
 505                 if (!udph->check)
 506                         udph->check = CSUM_MANGLED_0;
 507         }
 508 }
 509
 510 static void nf_flow_nat_port(struct sk_buff *skb, unsigned int thoff,
 511                              u8 protocol, __be16 port, __be16 new_port)
 512 {
 513         switch (protocol) {
 514         case IPPROTO_TCP:
 515                 nf_flow_nat_port_tcp(skb, thoff, port, new_port);
 516                 break;
 517         case IPPROTO_UDP:
 518                 nf_flow_nat_port_udp(skb, thoff, port, new_port);
 519                 break;
 520         }
 521 }
 522
 523 void nf_flow_snat_port(const struct flow_offload *flow,
 524                        struct sk_buff *skb, unsigned int thoff,
 525                        u8 protocol, enum flow_offload_tuple_dir dir)
 526 {
 527         struct flow_ports *hdr;
 528         __be16 port, new_port;
 529
 530         hdr = (void *)(skb_network_header(skb) + thoff);
 531
 532         switch (dir) {
 533         case FLOW_OFFLOAD_DIR_ORIGINAL:
 534                 port = hdr->source;
 535                 new_port = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_port;
 536                 hdr->source = new_port;
 537                 break;
 538         case FLOW_OFFLOAD_DIR_REPLY:
 539                 port = hdr->dest;
 540                 new_port = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_port;
 541                 hdr->dest = new_port;
 542                 break;
 543         }
 544
 545         nf_flow_nat_port(skb, thoff, protocol, port, new_port);
 546 }
 547 EXPORT_SYMBOL_GPL(nf_flow_snat_port);
 548
 549 void nf_flow_dnat_port(const struct flow_offload *flow, struct sk_buff *skb,
 550                        unsigned int thoff, u8 protocol,
 551                        enum flow_offload_tuple_dir dir)
 552 {
 553         struct flow_ports *hdr;
 554         __be16 port, new_port;
 555
 556         hdr = (void *)(skb_network_header(skb) + thoff);
 557
 558         switch (dir) {
 559         case FLOW_OFFLOAD_DIR_ORIGINAL:
 560                 port = hdr->dest;
 561                 new_port = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_port;
 562                 hdr->dest = new_port;
 563                 break;
 564         case FLOW_OFFLOAD_DIR_REPLY:
 565                 port = hdr->source;
 566                 new_port = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_port;
 567                 hdr->source = new_port;
 568                 break;
 569         }
 570
 571         nf_flow_nat_port(skb, thoff, protocol, port, new_port);
 572 }
 573 EXPORT_SYMBOL_GPL(nf_flow_dnat_port);
 574
 575 int nf_flow_table_init(struct nf_flowtable *flowtable)
 576 {
 577         int err;
 578
 579         INIT_DELAYED_WORK(&flowtable->gc_work, nf_flow_offload_work_gc);
 580         flow_block_init(&flowtable->flow_block);
 581         init_rwsem(&flowtable->flow_block_lock);
 582
 583         err = rhashtable_init(&flowtable->rhashtable,
 584                               &nf_flow_offload_rhash_params);
 585         if (err < 0)
 586                 return err;
 587
 588         queue_delayed_work(system_power_efficient_wq,
 589                            &flowtable->gc_work, HZ);
 590
 591         mutex_lock(&flowtable_lock);
 592         list_add(&flowtable->list, &flowtables);
 593         mutex_unlock(&flowtable_lock);
 594
 595         return 0;
 596 }
 597 EXPORT_SYMBOL_GPL(nf_flow_table_init);
 598
 599 static void nf_flow_table_do_cleanup(struct flow_offload *flow, void *data)
 600 {
 601         struct net_device *dev = data;
 602
 603         if (!dev) {
 604                 flow_offload_teardown(flow);
 605                 return;
 606         }
 607
 608         if (net_eq(nf_ct_net(flow->ct), dev_net(dev)) &&
 609             (flow->tuplehash[0].tuple.iifidx == dev->ifindex ||
 610              flow->tuplehash[1].tuple.iifidx == dev->ifindex))
 611                 flow_offload_teardown(flow);
 612 }
 613
 614 void nf_flow_table_gc_cleanup(struct nf_flowtable *flowtable,
 615                               struct net_device *dev)
 616 {
 617         nf_flow_table_iterate(flowtable, nf_flow_table_do_cleanup, dev);
 618         flush_delayed_work(&flowtable->gc_work);
 619         nf_flow_table_offload_flush(flowtable);
 620 }
 621
 622 void nf_flow_table_cleanup(struct net_device *dev)
 623 {
 624         struct nf_flowtable *flowtable;
 625
 626         mutex_lock(&flowtable_lock);
 627         list_for_each_entry(flowtable, &flowtables, list)
 628                 nf_flow_table_gc_cleanup(flowtable, dev);
 629         mutex_unlock(&flowtable_lock);
 630 }
 631 EXPORT_SYMBOL_GPL(nf_flow_table_cleanup);
 632
 633 void nf_flow_table_free(struct nf_flowtable *flow_table)
 634 {
 635         mutex_lock(&flowtable_lock);
 636         list_del(&flow_table->list);
 637         mutex_unlock(&flowtable_lock);
 638
 639         cancel_delayed_work_sync(&flow_table->gc_work);
 640         nf_flow_table_iterate(flow_table, nf_flow_table_do_cleanup, NULL);
 641         nf_flow_table_iterate(flow_table, nf_flow_offload_gc_step, flow_table);
 642         nf_flow_table_offload_flush(flow_table);
 643         if (nf_flowtable_hw_offload(flow_table))
 644                 nf_flow_table_iterate(flow_table, nf_flow_offload_gc_step,
 645                                       flow_table);
 646         rhashtable_destroy(&flow_table->rhashtable);
 647 }
 648 EXPORT_SYMBOL_GPL(nf_flow_table_free);
 649
 650 static int __init nf_flow_table_module_init(void)
 651 {
 652         return nf_flow_table_offload_init();
 653 }
 654
 655 static void __exit nf_flow_table_module_exit(void)
 656 {
 657         nf_flow_table_offload_exit();
 658 }
 659
 660 module_init(nf_flow_table_module_init);
 661 module_exit(nf_flow_table_module_exit);
 662
 663 MODULE_LICENSE("GPL");
 664 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
 665 MODULE_DESCRIPTION("Netfilter flow table module");