net/sched/act_ct.c

   1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
   2 /* -
   3  * net/sched/act_ct.c  Connection Tracking action
   4  *
   5  * Authors:   Paul Blakey <[email protected]>
   6  *            Yossi Kuperman <[email protected]>
   7  *            Marcelo Ricardo Leitner <[email protected]>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/rtnetlink.h>
  15 #include <linux/pkt_cls.h>
  16 #include <linux/ip.h>
  17 #include <linux/ipv6.h>
  18 #include <linux/rhashtable.h>
  19 #include <net/netlink.h>
  20 #include <net/pkt_sched.h>
  21 #include <net/pkt_cls.h>
  22 #include <net/act_api.h>
  23 #include <net/ip.h>
  24 #include <net/ipv6_frag.h>
  25 #include <uapi/linux/tc_act/tc_ct.h>
  26 #include <net/tc_act/tc_ct.h>
  27 #include <net/tc_wrapper.h>
  28
  29 #include <net/netfilter/nf_flow_table.h>
  30 #include <net/netfilter/nf_conntrack.h>
  31 #include <net/netfilter/nf_conntrack_core.h>
  32 #include <net/netfilter/nf_conntrack_zones.h>
  33 #include <net/netfilter/nf_conntrack_helper.h>
  34 #include <net/netfilter/nf_conntrack_acct.h>
  35 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
  36 #include <net/netfilter/nf_conntrack_act_ct.h>
  37 #include <net/netfilter/nf_conntrack_seqadj.h>
  38 #include <uapi/linux/netfilter/nf_nat.h>
  39
  40 static struct workqueue_struct *act_ct_wq;
  41 static struct rhashtable zones_ht;
  42 static DEFINE_MUTEX(zones_mutex);
  43
  44 struct tcf_ct_flow_table {
  45         struct rhash_head node; /* In zones tables */
  46
  47         struct rcu_work rwork;
  48         struct nf_flowtable nf_ft;
  49         refcount_t ref;
  50         u16 zone;
  51
  52         bool dying;
  53 };
  54
  55 static const struct rhashtable_params zones_params = {
  56         .head_offset = offsetof(struct tcf_ct_flow_table, node),
  57         .key_offset = offsetof(struct tcf_ct_flow_table, zone),
  58         .key_len = sizeof_field(struct tcf_ct_flow_table, zone),
  59         .automatic_shrinking = true,
  60 };
  61
  62 static struct flow_action_entry *
  63 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action)
  64 {
  65         int i = flow_action->num_entries++;
  66
  67         return &flow_action->entries[i];
  68 }
  69
  70 static void tcf_ct_add_mangle_action(struct flow_action *action,
  71                                      enum flow_action_mangle_base htype,
  72                                      u32 offset,
  73                                      u32 mask,
  74                                      u32 val)
  75 {
  76         struct flow_action_entry *entry;
  77
  78         entry = tcf_ct_flow_table_flow_action_get_next(action);
  79         entry->id = FLOW_ACTION_MANGLE;
  80         entry->mangle.htype = htype;
  81         entry->mangle.mask = ~mask;
  82         entry->mangle.offset = offset;
  83         entry->mangle.val = val;
  84 }
  85
  86 /* The following nat helper functions check if the inverted reverse tuple
  87  * (target) is different then the current dir tuple - meaning nat for ports
  88  * and/or ip is needed, and add the relevant mangle actions.
  89  */
  90 static void
  91 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple,
  92                                       struct nf_conntrack_tuple target,
  93                                       struct flow_action *action)
  94 {
  95         if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
  96                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
  97                                          offsetof(struct iphdr, saddr),
  98                                          0xFFFFFFFF,
  99                                          be32_to_cpu(target.src.u3.ip));
 100         if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
 101                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
 102                                          offsetof(struct iphdr, daddr),
 103                                          0xFFFFFFFF,
 104                                          be32_to_cpu(target.dst.u3.ip));
 105 }
 106
 107 static void
 108 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action,
 109                                    union nf_inet_addr *addr,
 110                                    u32 offset)
 111 {
 112         int i;
 113
 114         for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++)
 115                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
 116                                          i * sizeof(u32) + offset,
 117                                          0xFFFFFFFF, be32_to_cpu(addr->ip6[i]));
 118 }
 119
 120 static void
 121 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple,
 122                                       struct nf_conntrack_tuple target,
 123                                       struct flow_action *action)
 124 {
 125         if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
 126                 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3,
 127                                                    offsetof(struct ipv6hdr,
 128                                                             saddr));
 129         if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
 130                 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3,
 131                                                    offsetof(struct ipv6hdr,
 132                                                             daddr));
 133 }
 134
 135 static void
 136 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple,
 137                                      struct nf_conntrack_tuple target,
 138                                      struct flow_action *action)
 139 {
 140         __be16 target_src = target.src.u.tcp.port;
 141         __be16 target_dst = target.dst.u.tcp.port;
 142
 143         if (target_src != tuple->src.u.tcp.port)
 144                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
 145                                          offsetof(struct tcphdr, source),
 146                                          0xFFFF, be16_to_cpu(target_src));
 147         if (target_dst != tuple->dst.u.tcp.port)
 148                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
 149                                          offsetof(struct tcphdr, dest),
 150                                          0xFFFF, be16_to_cpu(target_dst));
 151 }
 152
 153 static void
 154 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple,
 155                                      struct nf_conntrack_tuple target,
 156                                      struct flow_action *action)
 157 {
 158         __be16 target_src = target.src.u.udp.port;
 159         __be16 target_dst = target.dst.u.udp.port;
 160
 161         if (target_src != tuple->src.u.udp.port)
 162                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
 163                                          offsetof(struct udphdr, source),
 164                                          0xFFFF, be16_to_cpu(target_src));
 165         if (target_dst != tuple->dst.u.udp.port)
 166                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
 167                                          offsetof(struct udphdr, dest),
 168                                          0xFFFF, be16_to_cpu(target_dst));
 169 }
 170
 171 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct,
 172                                               enum ip_conntrack_dir dir,
 173                                               struct flow_action *action)
 174 {
 175         struct nf_conn_labels *ct_labels;
 176         struct flow_action_entry *entry;
 177         enum ip_conntrack_info ctinfo;
 178         u32 *act_ct_labels;
 179
 180         entry = tcf_ct_flow_table_flow_action_get_next(action);
 181         entry->id = FLOW_ACTION_CT_METADATA;
 182 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 183         entry->ct_metadata.mark = READ_ONCE(ct->mark);
 184 #endif
 185         ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
 186                                              IP_CT_ESTABLISHED_REPLY;
 187         /* aligns with the CT reference on the SKB nf_ct_set */
 188         entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
 189         entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL;
 190
 191         act_ct_labels = entry->ct_metadata.labels;
 192         ct_labels = nf_ct_labels_find(ct);
 193         if (ct_labels)
 194                 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
 195         else
 196                 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
 197 }
 198
 199 static int tcf_ct_flow_table_add_action_nat(struct net *net,
 200                                             struct nf_conn *ct,
 201                                             enum ip_conntrack_dir dir,
 202                                             struct flow_action *action)
 203 {
 204         const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
 205         struct nf_conntrack_tuple target;
 206
 207         if (!(ct->status & IPS_NAT_MASK))
 208                 return 0;
 209
 210         nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
 211
 212         switch (tuple->src.l3num) {
 213         case NFPROTO_IPV4:
 214                 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
 215                                                       action);
 216                 break;
 217         case NFPROTO_IPV6:
 218                 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
 219                                                       action);
 220                 break;
 221         default:
 222                 return -EOPNOTSUPP;
 223         }
 224
 225         switch (nf_ct_protonum(ct)) {
 226         case IPPROTO_TCP:
 227                 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
 228                 break;
 229         case IPPROTO_UDP:
 230                 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
 231                 break;
 232         default:
 233                 return -EOPNOTSUPP;
 234         }
 235
 236         return 0;
 237 }
 238
 239 static int tcf_ct_flow_table_fill_actions(struct net *net,
 240                                           const struct flow_offload *flow,
 241                                           enum flow_offload_tuple_dir tdir,
 242                                           struct nf_flow_rule *flow_rule)
 243 {
 244         struct flow_action *action = &flow_rule->rule->action;
 245         int num_entries = action->num_entries;
 246         struct nf_conn *ct = flow->ct;
 247         enum ip_conntrack_dir dir;
 248         int i, err;
 249
 250         switch (tdir) {
 251         case FLOW_OFFLOAD_DIR_ORIGINAL:
 252                 dir = IP_CT_DIR_ORIGINAL;
 253                 break;
 254         case FLOW_OFFLOAD_DIR_REPLY:
 255                 dir = IP_CT_DIR_REPLY;
 256                 break;
 257         default:
 258                 return -EOPNOTSUPP;
 259         }
 260
 261         err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
 262         if (err)
 263                 goto err_nat;
 264
 265         tcf_ct_flow_table_add_action_meta(ct, dir, action);
 266         return 0;
 267
 268 err_nat:
 269         /* Clear filled actions */
 270         for (i = num_entries; i < action->num_entries; i++)
 271                 memset(&action->entries[i], 0, sizeof(action->entries[i]));
 272         action->num_entries = num_entries;
 273
 274         return err;
 275 }
 276
 277 static struct nf_flowtable_type flowtable_ct = {
 278         .action         = tcf_ct_flow_table_fill_actions,
 279         .owner          = THIS_MODULE,
 280 };
 281
 282 static int tcf_ct_flow_table_get(struct net *net, struct tcf_ct_params *params)
 283 {
 284         struct tcf_ct_flow_table *ct_ft;
 285         int err = -ENOMEM;
 286
 287         mutex_lock(&zones_mutex);
 288         ct_ft = rhashtable_lookup_fast(&zones_ht, &params->zone, zones_params);
 289         if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
 290                 goto out_unlock;
 291
 292         ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
 293         if (!ct_ft)
 294                 goto err_alloc;
 295         refcount_set(&ct_ft->ref, 1);
 296
 297         ct_ft->zone = params->zone;
 298         err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
 299         if (err)
 300                 goto err_insert;
 301
 302         ct_ft->nf_ft.type = &flowtable_ct;
 303         ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD |
 304                               NF_FLOWTABLE_COUNTER;
 305         err = nf_flow_table_init(&ct_ft->nf_ft);
 306         if (err)
 307                 goto err_init;
 308         write_pnet(&ct_ft->nf_ft.net, net);
 309
 310         __module_get(THIS_MODULE);
 311 out_unlock:
 312         params->ct_ft = ct_ft;
 313         params->nf_ft = &ct_ft->nf_ft;
 314         mutex_unlock(&zones_mutex);
 315
 316         return 0;
 317
 318 err_init:
 319         rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
 320 err_insert:
 321         kfree(ct_ft);
 322 err_alloc:
 323         mutex_unlock(&zones_mutex);
 324         return err;
 325 }
 326
 327 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
 328 {
 329         struct flow_block_cb *block_cb, *tmp_cb;
 330         struct tcf_ct_flow_table *ct_ft;
 331         struct flow_block *block;
 332
 333         ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
 334                              rwork);
 335         nf_flow_table_free(&ct_ft->nf_ft);
 336
 337         /* Remove any remaining callbacks before cleanup */
 338         block = &ct_ft->nf_ft.flow_block;
 339         down_write(&ct_ft->nf_ft.flow_block_lock);
 340         list_for_each_entry_safe(block_cb, tmp_cb, &block->cb_list, list) {
 341                 list_del(&block_cb->list);
 342                 flow_block_cb_free(block_cb);
 343         }
 344         up_write(&ct_ft->nf_ft.flow_block_lock);
 345         kfree(ct_ft);
 346
 347         module_put(THIS_MODULE);
 348 }
 349
 350 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft)
 351 {
 352         if (refcount_dec_and_test(&ct_ft->ref)) {
 353                 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
 354                 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
 355                 queue_rcu_work(act_ct_wq, &ct_ft->rwork);
 356         }
 357 }
 358
 359 static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry,
 360                                  struct nf_conn_act_ct_ext *act_ct_ext, u8 dir)
 361 {
 362         entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC;
 363         entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir];
 364 }
 365
 366 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
 367                                   struct nf_conn *ct,
 368                                   bool tcp)
 369 {
 370         struct nf_conn_act_ct_ext *act_ct_ext;
 371         struct flow_offload *entry;
 372         int err;
 373
 374         if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
 375                 return;
 376
 377         entry = flow_offload_alloc(ct);
 378         if (!entry) {
 379                 WARN_ON_ONCE(1);
 380                 goto err_alloc;
 381         }
 382
 383         if (tcp) {
 384                 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
 385                 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
 386         }
 387
 388         act_ct_ext = nf_conn_act_ct_ext_find(ct);
 389         if (act_ct_ext) {
 390                 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
 391                 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
 392         }
 393
 394         err = flow_offload_add(&ct_ft->nf_ft, entry);
 395         if (err)
 396                 goto err_add;
 397
 398         return;
 399
 400 err_add:
 401         flow_offload_free(entry);
 402 err_alloc:
 403         clear_bit(IPS_OFFLOAD_BIT, &ct->status);
 404 }
 405
 406 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
 407                                            struct nf_conn *ct,
 408                                            enum ip_conntrack_info ctinfo)
 409 {
 410         bool tcp = false;
 411
 412         if ((ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY) ||
 413             !test_bit(IPS_ASSURED_BIT, &ct->status))
 414                 return;
 415
 416         switch (nf_ct_protonum(ct)) {
 417         case IPPROTO_TCP:
 418                 tcp = true;
 419                 if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
 420                         return;
 421                 break;
 422         case IPPROTO_UDP:
 423                 break;
 424 #ifdef CONFIG_NF_CT_PROTO_GRE
 425         case IPPROTO_GRE: {
 426                 struct nf_conntrack_tuple *tuple;
 427
 428                 if (ct->status & IPS_NAT_MASK)
 429                         return;
 430                 tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
 431                 /* No support for GRE v1 */
 432                 if (tuple->src.u.gre.key || tuple->dst.u.gre.key)
 433                         return;
 434                 break;
 435         }
 436 #endif
 437         default:
 438                 return;
 439         }
 440
 441         if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
 442             ct->status & IPS_SEQ_ADJUST)
 443                 return;
 444
 445         tcf_ct_flow_table_add(ct_ft, ct, tcp);
 446 }
 447
 448 static bool
 449 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
 450                                   struct flow_offload_tuple *tuple,
 451                                   struct tcphdr **tcph)
 452 {
 453         struct flow_ports *ports;
 454         unsigned int thoff;
 455         struct iphdr *iph;
 456         size_t hdrsize;
 457         u8 ipproto;
 458
 459         if (!pskb_network_may_pull(skb, sizeof(*iph)))
 460                 return false;
 461
 462         iph = ip_hdr(skb);
 463         thoff = iph->ihl * 4;
 464
 465         if (ip_is_fragment(iph) ||
 466             unlikely(thoff != sizeof(struct iphdr)))
 467                 return false;
 468
 469         ipproto = iph->protocol;
 470         switch (ipproto) {
 471         case IPPROTO_TCP:
 472                 hdrsize = sizeof(struct tcphdr);
 473                 break;
 474         case IPPROTO_UDP:
 475                 hdrsize = sizeof(*ports);
 476                 break;
 477 #ifdef CONFIG_NF_CT_PROTO_GRE
 478         case IPPROTO_GRE:
 479                 hdrsize = sizeof(struct gre_base_hdr);
 480                 break;
 481 #endif
 482         default:
 483                 return false;
 484         }
 485
 486         if (iph->ttl <= 1)
 487                 return false;
 488
 489         if (!pskb_network_may_pull(skb, thoff + hdrsize))
 490                 return false;
 491
 492         switch (ipproto) {
 493         case IPPROTO_TCP:
 494                 *tcph = (void *)(skb_network_header(skb) + thoff);
 495                 fallthrough;
 496         case IPPROTO_UDP:
 497                 ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
 498                 tuple->src_port = ports->source;
 499                 tuple->dst_port = ports->dest;
 500                 break;
 501         case IPPROTO_GRE: {
 502                 struct gre_base_hdr *greh;
 503
 504                 greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
 505                 if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
 506                         return false;
 507                 break;
 508         }
 509         }
 510
 511         iph = ip_hdr(skb);
 512
 513         tuple->src_v4.s_addr = iph->saddr;
 514         tuple->dst_v4.s_addr = iph->daddr;
 515         tuple->l3proto = AF_INET;
 516         tuple->l4proto = ipproto;
 517
 518         return true;
 519 }
 520
 521 static bool
 522 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
 523                                   struct flow_offload_tuple *tuple,
 524                                   struct tcphdr **tcph)
 525 {
 526         struct flow_ports *ports;
 527         struct ipv6hdr *ip6h;
 528         unsigned int thoff;
 529         size_t hdrsize;
 530         u8 nexthdr;
 531
 532         if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
 533                 return false;
 534
 535         ip6h = ipv6_hdr(skb);
 536         thoff = sizeof(*ip6h);
 537
 538         nexthdr = ip6h->nexthdr;
 539         switch (nexthdr) {
 540         case IPPROTO_TCP:
 541                 hdrsize = sizeof(struct tcphdr);
 542                 break;
 543         case IPPROTO_UDP:
 544                 hdrsize = sizeof(*ports);
 545                 break;
 546 #ifdef CONFIG_NF_CT_PROTO_GRE
 547         case IPPROTO_GRE:
 548                 hdrsize = sizeof(struct gre_base_hdr);
 549                 break;
 550 #endif
 551         default:
 552                 return false;
 553         }
 554
 555         if (ip6h->hop_limit <= 1)
 556                 return false;
 557
 558         if (!pskb_network_may_pull(skb, thoff + hdrsize))
 559                 return false;
 560
 561         switch (nexthdr) {
 562         case IPPROTO_TCP:
 563                 *tcph = (void *)(skb_network_header(skb) + thoff);
 564                 fallthrough;
 565         case IPPROTO_UDP:
 566                 ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
 567                 tuple->src_port = ports->source;
 568                 tuple->dst_port = ports->dest;
 569                 break;
 570         case IPPROTO_GRE: {
 571                 struct gre_base_hdr *greh;
 572
 573                 greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
 574                 if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
 575                         return false;
 576                 break;
 577         }
 578         }
 579
 580         ip6h = ipv6_hdr(skb);
 581
 582         tuple->src_v6 = ip6h->saddr;
 583         tuple->dst_v6 = ip6h->daddr;
 584         tuple->l3proto = AF_INET6;
 585         tuple->l4proto = nexthdr;
 586
 587         return true;
 588 }
 589
 590 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
 591                                      struct sk_buff *skb,
 592                                      u8 family)
 593 {
 594         struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
 595         struct flow_offload_tuple_rhash *tuplehash;
 596         struct flow_offload_tuple tuple = {};
 597         enum ip_conntrack_info ctinfo;
 598         struct tcphdr *tcph = NULL;
 599         struct flow_offload *flow;
 600         struct nf_conn *ct;
 601         u8 dir;
 602
 603         switch (family) {
 604         case NFPROTO_IPV4:
 605                 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
 606                         return false;
 607                 break;
 608         case NFPROTO_IPV6:
 609                 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
 610                         return false;
 611                 break;
 612         default:
 613                 return false;
 614         }
 615
 616         tuplehash = flow_offload_lookup(nf_ft, &tuple);
 617         if (!tuplehash)
 618                 return false;
 619
 620         dir = tuplehash->tuple.dir;
 621         flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
 622         ct = flow->ct;
 623
 624         if (tcph && (unlikely(tcph->fin || tcph->rst))) {
 625                 flow_offload_teardown(flow);
 626                 return false;
 627         }
 628
 629         ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
 630                                                     IP_CT_ESTABLISHED_REPLY;
 631
 632         flow_offload_refresh(nf_ft, flow);
 633         nf_conntrack_get(&ct->ct_general);
 634         nf_ct_set(skb, ct, ctinfo);
 635         if (nf_ft->flags & NF_FLOWTABLE_COUNTER)
 636                 nf_ct_acct_update(ct, dir, skb->len);
 637
 638         return true;
 639 }
 640
 641 static int tcf_ct_flow_tables_init(void)
 642 {
 643         return rhashtable_init(&zones_ht, &zones_params);
 644 }
 645
 646 static void tcf_ct_flow_tables_uninit(void)
 647 {
 648         rhashtable_destroy(&zones_ht);
 649 }
 650
 651 static struct tc_action_ops act_ct_ops;
 652
 653 struct tc_ct_action_net {
 654         struct tc_action_net tn; /* Must be first */
 655         bool labels;
 656 };
 657
 658 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
 659 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
 660                                    struct tcf_ct_params *p)
 661 {
 662         enum ip_conntrack_info ctinfo;
 663         struct nf_conn *ct;
 664
 665         ct = nf_ct_get(skb, &ctinfo);
 666         if (!ct)
 667                 return false;
 668         if (!net_eq(net, read_pnet(&ct->ct_net)))
 669                 goto drop_ct;
 670         if (nf_ct_zone(ct)->id != p->zone)
 671                 goto drop_ct;
 672         if (p->helper) {
 673                 struct nf_conn_help *help;
 674
 675                 help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
 676                 if (help && rcu_access_pointer(help->helper) != p->helper)
 677                         goto drop_ct;
 678         }
 679
 680         /* Force conntrack entry direction. */
 681         if ((p->ct_action & TCA_CT_ACT_FORCE) &&
 682             CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
 683                 if (nf_ct_is_confirmed(ct))
 684                         nf_ct_kill(ct);
 685
 686                 goto drop_ct;
 687         }
 688
 689         return true;
 690
 691 drop_ct:
 692         nf_ct_put(ct);
 693         nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
 694
 695         return false;
 696 }
 697
 698 /* Trim the skb to the length specified by the IP/IPv6 header,
 699  * removing any trailing lower-layer padding. This prepares the skb
 700  * for higher-layer processing that assumes skb->len excludes padding
 701  * (such as nf_ip_checksum). The caller needs to pull the skb to the
 702  * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
 703  */
 704 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
 705 {
 706         unsigned int len;
 707
 708         switch (family) {
 709         case NFPROTO_IPV4:
 710                 len = ntohs(ip_hdr(skb)->tot_len);
 711                 break;
 712         case NFPROTO_IPV6:
 713                 len = sizeof(struct ipv6hdr)
 714                         + ntohs(ipv6_hdr(skb)->payload_len);
 715                 break;
 716         default:
 717                 len = skb->len;
 718         }
 719
 720         return pskb_trim_rcsum(skb, len);
 721 }
 722
 723 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
 724 {
 725         u8 family = NFPROTO_UNSPEC;
 726
 727         switch (skb_protocol(skb, true)) {
 728         case htons(ETH_P_IP):
 729                 family = NFPROTO_IPV4;
 730                 break;
 731         case htons(ETH_P_IPV6):
 732                 family = NFPROTO_IPV6;
 733                 break;
 734         default:
 735                 break;
 736         }
 737
 738         return family;
 739 }
 740
 741 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
 742 {
 743         unsigned int len;
 744
 745         len =  skb_network_offset(skb) + sizeof(struct iphdr);
 746         if (unlikely(skb->len < len))
 747                 return -EINVAL;
 748         if (unlikely(!pskb_may_pull(skb, len)))
 749                 return -ENOMEM;
 750
 751         *frag = ip_is_fragment(ip_hdr(skb));
 752         return 0;
 753 }
 754
 755 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
 756 {
 757         unsigned int flags = 0, len, payload_ofs = 0;
 758         unsigned short frag_off;
 759         int nexthdr;
 760
 761         len =  skb_network_offset(skb) + sizeof(struct ipv6hdr);
 762         if (unlikely(skb->len < len))
 763                 return -EINVAL;
 764         if (unlikely(!pskb_may_pull(skb, len)))
 765                 return -ENOMEM;
 766
 767         nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
 768         if (unlikely(nexthdr < 0))
 769                 return -EPROTO;
 770
 771         *frag = flags & IP6_FH_F_FRAG;
 772         return 0;
 773 }
 774
 775 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
 776                                    u8 family, u16 zone, bool *defrag)
 777 {
 778         enum ip_conntrack_info ctinfo;
 779         struct nf_conn *ct;
 780         int err = 0;
 781         bool frag;
 782         u16 mru;
 783
 784         /* Previously seen (loopback)? Ignore. */
 785         ct = nf_ct_get(skb, &ctinfo);
 786         if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
 787                 return 0;
 788
 789         if (family == NFPROTO_IPV4)
 790                 err = tcf_ct_ipv4_is_fragment(skb, &frag);
 791         else
 792                 err = tcf_ct_ipv6_is_fragment(skb, &frag);
 793         if (err || !frag)
 794                 return err;
 795
 796         skb_get(skb);
 797         mru = tc_skb_cb(skb)->mru;
 798
 799         if (family == NFPROTO_IPV4) {
 800                 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
 801
 802                 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 803                 local_bh_disable();
 804                 err = ip_defrag(net, skb, user);
 805                 local_bh_enable();
 806                 if (err && err != -EINPROGRESS)
 807                         return err;
 808
 809                 if (!err) {
 810                         *defrag = true;
 811                         mru = IPCB(skb)->frag_max_size;
 812                 }
 813         } else { /* NFPROTO_IPV6 */
 814 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
 815                 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
 816
 817                 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
 818                 err = nf_ct_frag6_gather(net, skb, user);
 819                 if (err && err != -EINPROGRESS)
 820                         goto out_free;
 821
 822                 if (!err) {
 823                         *defrag = true;
 824                         mru = IP6CB(skb)->frag_max_size;
 825                 }
 826 #else
 827                 err = -EOPNOTSUPP;
 828                 goto out_free;
 829 #endif
 830         }
 831
 832         if (err != -EINPROGRESS)
 833                 tc_skb_cb(skb)->mru = mru;
 834         skb_clear_hash(skb);
 835         skb->ignore_df = 1;
 836         return err;
 837
 838 out_free:
 839         kfree_skb(skb);
 840         return err;
 841 }
 842
 843 static void tcf_ct_params_free(struct tcf_ct_params *params)
 844 {
 845         if (params->helper) {
 846 #if IS_ENABLED(CONFIG_NF_NAT)
 847                 if (params->ct_action & TCA_CT_ACT_NAT)
 848                         nf_nat_helper_put(params->helper);
 849 #endif
 850                 nf_conntrack_helper_put(params->helper);
 851         }
 852         if (params->ct_ft)
 853                 tcf_ct_flow_table_put(params->ct_ft);
 854         if (params->tmpl)
 855                 nf_ct_put(params->tmpl);
 856         kfree(params);
 857 }
 858
 859 static void tcf_ct_params_free_rcu(struct rcu_head *head)
 860 {
 861         struct tcf_ct_params *params;
 862
 863         params = container_of(head, struct tcf_ct_params, rcu);
 864         tcf_ct_params_free(params);
 865 }
 866
 867 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
 868 {
 869 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 870         u32 new_mark;
 871
 872         if (!mask)
 873                 return;
 874
 875         new_mark = mark | (READ_ONCE(ct->mark) & ~(mask));
 876         if (READ_ONCE(ct->mark) != new_mark) {
 877                 WRITE_ONCE(ct->mark, new_mark);
 878                 if (nf_ct_is_confirmed(ct))
 879                         nf_conntrack_event_cache(IPCT_MARK, ct);
 880         }
 881 #endif
 882 }
 883
 884 static void tcf_ct_act_set_labels(struct nf_conn *ct,
 885                                   u32 *labels,
 886                                   u32 *labels_m)
 887 {
 888 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
 889         size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
 890
 891         if (!memchr_inv(labels_m, 0, labels_sz))
 892                 return;
 893
 894         nf_connlabels_replace(ct, labels, labels_m, 4);
 895 #endif
 896 }
 897
 898 static int tcf_ct_act_nat(struct sk_buff *skb,
 899                           struct nf_conn *ct,
 900                           enum ip_conntrack_info ctinfo,
 901                           int ct_action,
 902                           struct nf_nat_range2 *range,
 903                           bool commit)
 904 {
 905 #if IS_ENABLED(CONFIG_NF_NAT)
 906         int err, action = 0;
 907
 908         if (!(ct_action & TCA_CT_ACT_NAT))
 909                 return NF_ACCEPT;
 910         if (ct_action & TCA_CT_ACT_NAT_SRC)
 911                 action |= BIT(NF_NAT_MANIP_SRC);
 912         if (ct_action & TCA_CT_ACT_NAT_DST)
 913                 action |= BIT(NF_NAT_MANIP_DST);
 914
 915         err = nf_ct_nat(skb, ct, ctinfo, &action, range, commit);
 916
 917         if (action & BIT(NF_NAT_MANIP_SRC))
 918                 tc_skb_cb(skb)->post_ct_snat = 1;
 919         if (action & BIT(NF_NAT_MANIP_DST))
 920                 tc_skb_cb(skb)->post_ct_dnat = 1;
 921
 922         return err;
 923 #else
 924         return NF_ACCEPT;
 925 #endif
 926 }
 927
 928 TC_INDIRECT_SCOPE int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
 929                                  struct tcf_result *res)
 930 {
 931         struct net *net = dev_net(skb->dev);
 932         enum ip_conntrack_info ctinfo;
 933         struct tcf_ct *c = to_ct(a);
 934         struct nf_conn *tmpl = NULL;
 935         struct nf_hook_state state;
 936         bool cached, commit, clear;
 937         int nh_ofs, err, retval;
 938         struct tcf_ct_params *p;
 939         bool add_helper = false;
 940         bool skip_add = false;
 941         bool defrag = false;
 942         struct nf_conn *ct;
 943         u8 family;
 944
 945         p = rcu_dereference_bh(c->params);
 946
 947         retval = READ_ONCE(c->tcf_action);
 948         commit = p->ct_action & TCA_CT_ACT_COMMIT;
 949         clear = p->ct_action & TCA_CT_ACT_CLEAR;
 950         tmpl = p->tmpl;
 951
 952         tcf_lastuse_update(&c->tcf_tm);
 953         tcf_action_update_bstats(&c->common, skb);
 954
 955         if (clear) {
 956                 tc_skb_cb(skb)->post_ct = false;
 957                 ct = nf_ct_get(skb, &ctinfo);
 958                 if (ct) {
 959                         nf_ct_put(ct);
 960                         nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
 961                 }
 962
 963                 goto out_clear;
 964         }
 965
 966         family = tcf_ct_skb_nf_family(skb);
 967         if (family == NFPROTO_UNSPEC)
 968                 goto drop;
 969
 970         /* The conntrack module expects to be working at L3.
 971          * We also try to pull the IPv4/6 header to linear area
 972          */
 973         nh_ofs = skb_network_offset(skb);
 974         skb_pull_rcsum(skb, nh_ofs);
 975         err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
 976         if (err == -EINPROGRESS) {
 977                 retval = TC_ACT_STOLEN;
 978                 goto out_clear;
 979         }
 980         if (err)
 981                 goto drop;
 982
 983         err = tcf_ct_skb_network_trim(skb, family);
 984         if (err)
 985                 goto drop;
 986
 987         /* If we are recirculating packets to match on ct fields and
 988          * committing with a separate ct action, then we don't need to
 989          * actually run the packet through conntrack twice unless it's for a
 990          * different zone.
 991          */
 992         cached = tcf_ct_skb_nfct_cached(net, skb, p);
 993         if (!cached) {
 994                 if (tcf_ct_flow_table_lookup(p, skb, family)) {
 995                         skip_add = true;
 996                         goto do_nat;
 997                 }
 998
 999                 /* Associate skb with specified zone. */
1000                 if (tmpl) {
1001                         nf_conntrack_put(skb_nfct(skb));
1002                         nf_conntrack_get(&tmpl->ct_general);
1003                         nf_ct_set(skb, tmpl, IP_CT_NEW);
1004                 }
1005
1006                 state.hook = NF_INET_PRE_ROUTING;
1007                 state.net = net;
1008                 state.pf = family;
1009                 err = nf_conntrack_in(skb, &state);
1010                 if (err != NF_ACCEPT)
1011                         goto out_push;
1012         }
1013
1014 do_nat:
1015         ct = nf_ct_get(skb, &ctinfo);
1016         if (!ct)
1017                 goto out_push;
1018         nf_ct_deliver_cached_events(ct);
1019         nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
1020
1021         err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1022         if (err != NF_ACCEPT)
1023                 goto drop;
1024
1025         if (!nf_ct_is_confirmed(ct) && commit && p->helper && !nfct_help(ct)) {
1026                 err = __nf_ct_try_assign_helper(ct, p->tmpl, GFP_ATOMIC);
1027                 if (err)
1028                         goto drop;
1029                 add_helper = true;
1030                 if (p->ct_action & TCA_CT_ACT_NAT && !nfct_seqadj(ct)) {
1031                         if (!nfct_seqadj_ext_add(ct))
1032                                 goto drop;
1033                 }
1034         }
1035
1036         if (nf_ct_is_confirmed(ct) ? ((!cached && !skip_add) || add_helper) : commit) {
1037                 if (nf_ct_helper(skb, ct, ctinfo, family) != NF_ACCEPT)
1038                         goto drop;
1039         }
1040
1041         if (commit) {
1042                 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1043                 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1044
1045                 if (!nf_ct_is_confirmed(ct))
1046                         nf_conn_act_ct_ext_add(ct);
1047
1048                 /* This will take care of sending queued events
1049                  * even if the connection is already confirmed.
1050                  */
1051                 if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1052                         goto drop;
1053         }
1054
1055         if (!skip_add)
1056                 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1057
1058 out_push:
1059         skb_push_rcsum(skb, nh_ofs);
1060
1061         tc_skb_cb(skb)->post_ct = true;
1062         tc_skb_cb(skb)->zone = p->zone;
1063 out_clear:
1064         if (defrag)
1065                 qdisc_skb_cb(skb)->pkt_len = skb->len;
1066         return retval;
1067
1068 drop:
1069         tcf_action_inc_drop_qstats(&c->common);
1070         return TC_ACT_SHOT;
1071 }
1072
1073 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1074         [TCA_CT_ACTION] = { .type = NLA_U16 },
1075         [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)),
1076         [TCA_CT_ZONE] = { .type = NLA_U16 },
1077         [TCA_CT_MARK] = { .type = NLA_U32 },
1078         [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1079         [TCA_CT_LABELS] = { .type = NLA_BINARY,
1080                             .len = 128 / BITS_PER_BYTE },
1081         [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1082                                  .len = 128 / BITS_PER_BYTE },
1083         [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1084         [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1085         [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1086         [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1087         [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1088         [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1089         [TCA_CT_HELPER_NAME] = { .type = NLA_STRING, .len = NF_CT_HELPER_NAME_LEN },
1090         [TCA_CT_HELPER_FAMILY] = { .type = NLA_U8 },
1091         [TCA_CT_HELPER_PROTO] = { .type = NLA_U8 },
1092 };
1093
1094 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1095                                   struct tc_ct *parm,
1096                                   struct nlattr **tb,
1097                                   struct netlink_ext_ack *extack)
1098 {
1099         struct nf_nat_range2 *range;
1100
1101         if (!(p->ct_action & TCA_CT_ACT_NAT))
1102                 return 0;
1103
1104         if (!IS_ENABLED(CONFIG_NF_NAT)) {
1105                 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1106                 return -EOPNOTSUPP;
1107         }
1108
1109         if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1110                 return 0;
1111
1112         if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1113             (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1114                 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1115                 return -EOPNOTSUPP;
1116         }
1117
1118         range = &p->range;
1119         if (tb[TCA_CT_NAT_IPV4_MIN]) {
1120                 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1121
1122                 p->ipv4_range = true;
1123                 range->flags |= NF_NAT_RANGE_MAP_IPS;
1124                 range->min_addr.ip =
1125                         nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1126
1127                 range->max_addr.ip = max_attr ?
1128                                      nla_get_in_addr(max_attr) :
1129                                      range->min_addr.ip;
1130         } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1131                 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1132
1133                 p->ipv4_range = false;
1134                 range->flags |= NF_NAT_RANGE_MAP_IPS;
1135                 range->min_addr.in6 =
1136                         nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1137
1138                 range->max_addr.in6 = max_attr ?
1139                                       nla_get_in6_addr(max_attr) :
1140                                       range->min_addr.in6;
1141         }
1142
1143         if (tb[TCA_CT_NAT_PORT_MIN]) {
1144                 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1145                 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1146
1147                 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1148                                        nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1149                                        range->min_proto.all;
1150         }
1151
1152         return 0;
1153 }
1154
1155 static void tcf_ct_set_key_val(struct nlattr **tb,
1156                                void *val, int val_type,
1157                                void *mask, int mask_type,
1158                                int len)
1159 {
1160         if (!tb[val_type])
1161                 return;
1162         nla_memcpy(val, tb[val_type], len);
1163
1164         if (!mask)
1165                 return;
1166
1167         if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1168                 memset(mask, 0xff, len);
1169         else
1170                 nla_memcpy(mask, tb[mask_type], len);
1171 }
1172
1173 static int tcf_ct_fill_params(struct net *net,
1174                               struct tcf_ct_params *p,
1175                               struct tc_ct *parm,
1176                               struct nlattr **tb,
1177                               struct netlink_ext_ack *extack)
1178 {
1179         struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1180         struct nf_conntrack_zone zone;
1181         int err, family, proto, len;
1182         struct nf_conn *tmpl;
1183         char *name;
1184
1185         p->zone = NF_CT_DEFAULT_ZONE_ID;
1186
1187         tcf_ct_set_key_val(tb,
1188                            &p->ct_action, TCA_CT_ACTION,
1189                            NULL, TCA_CT_UNSPEC,
1190                            sizeof(p->ct_action));
1191
1192         if (p->ct_action & TCA_CT_ACT_CLEAR)
1193                 return 0;
1194
1195         err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1196         if (err)
1197                 return err;
1198
1199         if (tb[TCA_CT_MARK]) {
1200                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1201                         NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1202                         return -EOPNOTSUPP;
1203                 }
1204                 tcf_ct_set_key_val(tb,
1205                                    &p->mark, TCA_CT_MARK,
1206                                    &p->mark_mask, TCA_CT_MARK_MASK,
1207                                    sizeof(p->mark));
1208         }
1209
1210         if (tb[TCA_CT_LABELS]) {
1211                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1212                         NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1213                         return -EOPNOTSUPP;
1214                 }
1215
1216                 if (!tn->labels) {
1217                         NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1218                         return -EOPNOTSUPP;
1219                 }
1220                 tcf_ct_set_key_val(tb,
1221                                    p->labels, TCA_CT_LABELS,
1222                                    p->labels_mask, TCA_CT_LABELS_MASK,
1223                                    sizeof(p->labels));
1224         }
1225
1226         if (tb[TCA_CT_ZONE]) {
1227                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1228                         NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1229                         return -EOPNOTSUPP;
1230                 }
1231
1232                 tcf_ct_set_key_val(tb,
1233                                    &p->zone, TCA_CT_ZONE,
1234                                    NULL, TCA_CT_UNSPEC,
1235                                    sizeof(p->zone));
1236         }
1237
1238         nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1239         tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1240         if (!tmpl) {
1241                 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1242                 return -ENOMEM;
1243         }
1244         p->tmpl = tmpl;
1245         if (tb[TCA_CT_HELPER_NAME]) {
1246                 name = nla_data(tb[TCA_CT_HELPER_NAME]);
1247                 len = nla_len(tb[TCA_CT_HELPER_NAME]);
1248                 if (len > 16 || name[len - 1] != '\0') {
1249                         NL_SET_ERR_MSG_MOD(extack, "Failed to parse helper name.");
1250                         err = -EINVAL;
1251                         goto err;
1252                 }
1253                 family = tb[TCA_CT_HELPER_FAMILY] ? nla_get_u8(tb[TCA_CT_HELPER_FAMILY]) : AF_INET;
1254                 proto = tb[TCA_CT_HELPER_PROTO] ? nla_get_u8(tb[TCA_CT_HELPER_PROTO]) : IPPROTO_TCP;
1255                 err = nf_ct_add_helper(tmpl, name, family, proto,
1256                                        p->ct_action & TCA_CT_ACT_NAT, &p->helper);
1257                 if (err) {
1258                         NL_SET_ERR_MSG_MOD(extack, "Failed to add helper");
1259                         goto err;
1260                 }
1261         }
1262
1263         __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1264         return 0;
1265 err:
1266         nf_ct_put(p->tmpl);
1267         p->tmpl = NULL;
1268         return err;
1269 }
1270
1271 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1272                        struct nlattr *est, struct tc_action **a,
1273                        struct tcf_proto *tp, u32 flags,
1274                        struct netlink_ext_ack *extack)
1275 {
1276         struct tc_action_net *tn = net_generic(net, act_ct_ops.net_id);
1277         bool bind = flags & TCA_ACT_FLAGS_BIND;
1278         struct tcf_ct_params *params = NULL;
1279         struct nlattr *tb[TCA_CT_MAX + 1];
1280         struct tcf_chain *goto_ch = NULL;
1281         struct tc_ct *parm;
1282         struct tcf_ct *c;
1283         int err, res = 0;
1284         u32 index;
1285
1286         if (!nla) {
1287                 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1288                 return -EINVAL;
1289         }
1290
1291         err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1292         if (err < 0)
1293                 return err;
1294
1295         if (!tb[TCA_CT_PARMS]) {
1296                 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1297                 return -EINVAL;
1298         }
1299         parm = nla_data(tb[TCA_CT_PARMS]);
1300         index = parm->index;
1301         err = tcf_idr_check_alloc(tn, &index, a, bind);
1302         if (err < 0)
1303                 return err;
1304
1305         if (!err) {
1306                 err = tcf_idr_create_from_flags(tn, index, est, a,
1307                                                 &act_ct_ops, bind, flags);
1308                 if (err) {
1309                         tcf_idr_cleanup(tn, index);
1310                         return err;
1311                 }
1312                 res = ACT_P_CREATED;
1313         } else {
1314                 if (bind)
1315                         return 0;
1316
1317                 if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
1318                         tcf_idr_release(*a, bind);
1319                         return -EEXIST;
1320                 }
1321         }
1322         err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1323         if (err < 0)
1324                 goto cleanup;
1325
1326         c = to_ct(*a);
1327
1328         params = kzalloc(sizeof(*params), GFP_KERNEL);
1329         if (unlikely(!params)) {
1330                 err = -ENOMEM;
1331                 goto cleanup;
1332         }
1333
1334         err = tcf_ct_fill_params(net, params, parm, tb, extack);
1335         if (err)
1336                 goto cleanup;
1337
1338         err = tcf_ct_flow_table_get(net, params);
1339         if (err)
1340                 goto cleanup;
1341
1342         spin_lock_bh(&c->tcf_lock);
1343         goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1344         params = rcu_replace_pointer(c->params, params,
1345                                      lockdep_is_held(&c->tcf_lock));
1346         spin_unlock_bh(&c->tcf_lock);
1347
1348         if (goto_ch)
1349                 tcf_chain_put_by_act(goto_ch);
1350         if (params)
1351                 call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1352
1353         return res;
1354
1355 cleanup:
1356         if (goto_ch)
1357                 tcf_chain_put_by_act(goto_ch);
1358         if (params)
1359                 tcf_ct_params_free(params);
1360         tcf_idr_release(*a, bind);
1361         return err;
1362 }
1363
1364 static void tcf_ct_cleanup(struct tc_action *a)
1365 {
1366         struct tcf_ct_params *params;
1367         struct tcf_ct *c = to_ct(a);
1368
1369         params = rcu_dereference_protected(c->params, 1);
1370         if (params)
1371                 call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1372 }
1373
1374 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1375                                void *val, int val_type,
1376                                void *mask, int mask_type,
1377                                int len)
1378 {
1379         int err;
1380
1381         if (mask && !memchr_inv(mask, 0, len))
1382                 return 0;
1383
1384         err = nla_put(skb, val_type, len, val);
1385         if (err)
1386                 return err;
1387
1388         if (mask_type != TCA_CT_UNSPEC) {
1389                 err = nla_put(skb, mask_type, len, mask);
1390                 if (err)
1391                         return err;
1392         }
1393
1394         return 0;
1395 }
1396
1397 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1398 {
1399         struct nf_nat_range2 *range = &p->range;
1400
1401         if (!(p->ct_action & TCA_CT_ACT_NAT))
1402                 return 0;
1403
1404         if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1405                 return 0;
1406
1407         if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1408                 if (p->ipv4_range) {
1409                         if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1410                                             range->min_addr.ip))
1411                                 return -1;
1412                         if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1413                                             range->max_addr.ip))
1414                                 return -1;
1415                 } else {
1416                         if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1417                                              &range->min_addr.in6))
1418                                 return -1;
1419                         if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1420                                              &range->max_addr.in6))
1421                                 return -1;
1422                 }
1423         }
1424
1425         if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1426                 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1427                                  range->min_proto.all))
1428                         return -1;
1429                 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1430                                  range->max_proto.all))
1431                         return -1;
1432         }
1433
1434         return 0;
1435 }
1436
1437 static int tcf_ct_dump_helper(struct sk_buff *skb, struct nf_conntrack_helper *helper)
1438 {
1439         if (!helper)
1440                 return 0;
1441
1442         if (nla_put_string(skb, TCA_CT_HELPER_NAME, helper->name) ||
1443             nla_put_u8(skb, TCA_CT_HELPER_FAMILY, helper->tuple.src.l3num) ||
1444             nla_put_u8(skb, TCA_CT_HELPER_PROTO, helper->tuple.dst.protonum))
1445                 return -1;
1446
1447         return 0;
1448 }
1449
1450 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1451                               int bind, int ref)
1452 {
1453         unsigned char *b = skb_tail_pointer(skb);
1454         struct tcf_ct *c = to_ct(a);
1455         struct tcf_ct_params *p;
1456
1457         struct tc_ct opt = {
1458                 .index   = c->tcf_index,
1459                 .refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1460                 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1461         };
1462         struct tcf_t t;
1463
1464         spin_lock_bh(&c->tcf_lock);
1465         p = rcu_dereference_protected(c->params,
1466                                       lockdep_is_held(&c->tcf_lock));
1467         opt.action = c->tcf_action;
1468
1469         if (tcf_ct_dump_key_val(skb,
1470                                 &p->ct_action, TCA_CT_ACTION,
1471                                 NULL, TCA_CT_UNSPEC,
1472                                 sizeof(p->ct_action)))
1473                 goto nla_put_failure;
1474
1475         if (p->ct_action & TCA_CT_ACT_CLEAR)
1476                 goto skip_dump;
1477
1478         if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1479             tcf_ct_dump_key_val(skb,
1480                                 &p->mark, TCA_CT_MARK,
1481                                 &p->mark_mask, TCA_CT_MARK_MASK,
1482                                 sizeof(p->mark)))
1483                 goto nla_put_failure;
1484
1485         if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1486             tcf_ct_dump_key_val(skb,
1487                                 p->labels, TCA_CT_LABELS,
1488                                 p->labels_mask, TCA_CT_LABELS_MASK,
1489                                 sizeof(p->labels)))
1490                 goto nla_put_failure;
1491
1492         if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1493             tcf_ct_dump_key_val(skb,
1494                                 &p->zone, TCA_CT_ZONE,
1495                                 NULL, TCA_CT_UNSPEC,
1496                                 sizeof(p->zone)))
1497                 goto nla_put_failure;
1498
1499         if (tcf_ct_dump_nat(skb, p))
1500                 goto nla_put_failure;
1501
1502         if (tcf_ct_dump_helper(skb, p->helper))
1503                 goto nla_put_failure;
1504
1505 skip_dump:
1506         if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1507                 goto nla_put_failure;
1508
1509         tcf_tm_dump(&t, &c->tcf_tm);
1510         if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1511                 goto nla_put_failure;
1512         spin_unlock_bh(&c->tcf_lock);
1513
1514         return skb->len;
1515 nla_put_failure:
1516         spin_unlock_bh(&c->tcf_lock);
1517         nlmsg_trim(skb, b);
1518         return -1;
1519 }
1520
1521 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1522                              u64 drops, u64 lastuse, bool hw)
1523 {
1524         struct tcf_ct *c = to_ct(a);
1525
1526         tcf_action_update_stats(a, bytes, packets, drops, hw);
1527         c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1528 }
1529
1530 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data,
1531                                     u32 *index_inc, bool bind,
1532                                     struct netlink_ext_ack *extack)
1533 {
1534         if (bind) {
1535                 struct flow_action_entry *entry = entry_data;
1536
1537                 entry->id = FLOW_ACTION_CT;
1538                 entry->ct.action = tcf_ct_action(act);
1539                 entry->ct.zone = tcf_ct_zone(act);
1540                 entry->ct.flow_table = tcf_ct_ft(act);
1541                 *index_inc = 1;
1542         } else {
1543                 struct flow_offload_action *fl_action = entry_data;
1544
1545                 fl_action->id = FLOW_ACTION_CT;
1546         }
1547
1548         return 0;
1549 }
1550
1551 static struct tc_action_ops act_ct_ops = {
1552         .kind           =       "ct",
1553         .id             =       TCA_ID_CT,
1554         .owner          =       THIS_MODULE,
1555         .act            =       tcf_ct_act,
1556         .dump           =       tcf_ct_dump,
1557         .init           =       tcf_ct_init,
1558         .cleanup        =       tcf_ct_cleanup,
1559         .stats_update   =       tcf_stats_update,
1560         .offload_act_setup =    tcf_ct_offload_act_setup,
1561         .size           =       sizeof(struct tcf_ct),
1562 };
1563
1564 static __net_init int ct_init_net(struct net *net)
1565 {
1566         unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1567         struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1568
1569         if (nf_connlabels_get(net, n_bits - 1)) {
1570                 tn->labels = false;
1571                 pr_err("act_ct: Failed to set connlabels length");
1572         } else {
1573                 tn->labels = true;
1574         }
1575
1576         return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1577 }
1578
1579 static void __net_exit ct_exit_net(struct list_head *net_list)
1580 {
1581         struct net *net;
1582
1583         rtnl_lock();
1584         list_for_each_entry(net, net_list, exit_list) {
1585                 struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1586
1587                 if (tn->labels)
1588                         nf_connlabels_put(net);
1589         }
1590         rtnl_unlock();
1591
1592         tc_action_net_exit(net_list, act_ct_ops.net_id);
1593 }
1594
1595 static struct pernet_operations ct_net_ops = {
1596         .init = ct_init_net,
1597         .exit_batch = ct_exit_net,
1598         .id   = &act_ct_ops.net_id,
1599         .size = sizeof(struct tc_ct_action_net),
1600 };
1601
1602 static int __init ct_init_module(void)
1603 {
1604         int err;
1605
1606         act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1607         if (!act_ct_wq)
1608                 return -ENOMEM;
1609
1610         err = tcf_ct_flow_tables_init();
1611         if (err)
1612                 goto err_tbl_init;
1613
1614         err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1615         if (err)
1616                 goto err_register;
1617
1618         static_branch_inc(&tcf_frag_xmit_count);
1619
1620         return 0;
1621
1622 err_register:
1623         tcf_ct_flow_tables_uninit();
1624 err_tbl_init:
1625         destroy_workqueue(act_ct_wq);
1626         return err;
1627 }
1628
1629 static void __exit ct_cleanup_module(void)
1630 {
1631         static_branch_dec(&tcf_frag_xmit_count);
1632         tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1633         tcf_ct_flow_tables_uninit();
1634         destroy_workqueue(act_ct_wq);
1635 }
1636
1637 module_init(ct_init_module);
1638 module_exit(ct_cleanup_module);
1639 MODULE_AUTHOR("Paul Blakey <[email protected]>");
1640 MODULE_AUTHOR("Yossi Kuperman <[email protected]>");
1641 MODULE_AUTHOR("Marcelo Ricardo Leitner <[email protected]>");
1642 MODULE_DESCRIPTION("Connection tracking action");
1643 MODULE_LICENSE("GPL v2");