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 <paulb@mellanox.com>
   6  *            Yossi Kuperman <yossiku@mellanox.com>
   7  *            Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
   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
  28 #include <net/netfilter/nf_flow_table.h>
  29 #include <net/netfilter/nf_conntrack.h>
  30 #include <net/netfilter/nf_conntrack_core.h>
  31 #include <net/netfilter/nf_conntrack_zones.h>
  32 #include <net/netfilter/nf_conntrack_helper.h>
  33 #include <net/netfilter/nf_conntrack_acct.h>
  34 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
  35 #include <uapi/linux/netfilter/nf_nat.h>
  36
  37 static struct workqueue_struct *act_ct_wq;
  38 static struct rhashtable zones_ht;
  39 static DEFINE_MUTEX(zones_mutex);
  40
  41 struct tcf_ct_flow_table {
  42         struct rhash_head node; /* In zones tables */
  43
  44         struct rcu_work rwork;
  45         struct nf_flowtable nf_ft;
  46         refcount_t ref;
  47         u16 zone;
  48
  49         bool dying;
  50 };
  51
  52 static const struct rhashtable_params zones_params = {
  53         .head_offset = offsetof(struct tcf_ct_flow_table, node),
  54         .key_offset = offsetof(struct tcf_ct_flow_table, zone),
  55         .key_len = sizeof_field(struct tcf_ct_flow_table, zone),
  56         .automatic_shrinking = true,
  57 };
  58
  59 static struct flow_action_entry *
  60 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action)
  61 {
  62         int i = flow_action->num_entries++;
  63
  64         return &flow_action->entries[i];
  65 }
  66
  67 static void tcf_ct_add_mangle_action(struct flow_action *action,
  68                                      enum flow_action_mangle_base htype,
  69                                      u32 offset,
  70                                      u32 mask,
  71                                      u32 val)
  72 {
  73         struct flow_action_entry *entry;
  74
  75         entry = tcf_ct_flow_table_flow_action_get_next(action);
  76         entry->id = FLOW_ACTION_MANGLE;
  77         entry->mangle.htype = htype;
  78         entry->mangle.mask = ~mask;
  79         entry->mangle.offset = offset;
  80         entry->mangle.val = val;
  81 }
  82
  83 /* The following nat helper functions check if the inverted reverse tuple
  84  * (target) is different then the current dir tuple - meaning nat for ports
  85  * and/or ip is needed, and add the relevant mangle actions.
  86  */
  87 static void
  88 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple,
  89                                       struct nf_conntrack_tuple target,
  90                                       struct flow_action *action)
  91 {
  92         if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
  93                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
  94                                          offsetof(struct iphdr, saddr),
  95                                          0xFFFFFFFF,
  96                                          be32_to_cpu(target.src.u3.ip));
  97         if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
  98                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
  99                                          offsetof(struct iphdr, daddr),
 100                                          0xFFFFFFFF,
 101                                          be32_to_cpu(target.dst.u3.ip));
 102 }
 103
 104 static void
 105 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action,
 106                                    union nf_inet_addr *addr,
 107                                    u32 offset)
 108 {
 109         int i;
 110
 111         for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++)
 112                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
 113                                          i * sizeof(u32) + offset,
 114                                          0xFFFFFFFF, be32_to_cpu(addr->ip6[i]));
 115 }
 116
 117 static void
 118 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple,
 119                                       struct nf_conntrack_tuple target,
 120                                       struct flow_action *action)
 121 {
 122         if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
 123                 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3,
 124                                                    offsetof(struct ipv6hdr,
 125                                                             saddr));
 126         if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
 127                 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3,
 128                                                    offsetof(struct ipv6hdr,
 129                                                             daddr));
 130 }
 131
 132 static void
 133 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple,
 134                                      struct nf_conntrack_tuple target,
 135                                      struct flow_action *action)
 136 {
 137         __be16 target_src = target.src.u.tcp.port;
 138         __be16 target_dst = target.dst.u.tcp.port;
 139
 140         if (target_src != tuple->src.u.tcp.port)
 141                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
 142                                          offsetof(struct tcphdr, source),
 143                                          0xFFFF, be16_to_cpu(target_src));
 144         if (target_dst != tuple->dst.u.tcp.port)
 145                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
 146                                          offsetof(struct tcphdr, dest),
 147                                          0xFFFF, be16_to_cpu(target_dst));
 148 }
 149
 150 static void
 151 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple,
 152                                      struct nf_conntrack_tuple target,
 153                                      struct flow_action *action)
 154 {
 155         __be16 target_src = target.src.u.udp.port;
 156         __be16 target_dst = target.dst.u.udp.port;
 157
 158         if (target_src != tuple->src.u.udp.port)
 159                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
 160                                          offsetof(struct udphdr, source),
 161                                          0xFFFF, be16_to_cpu(target_src));
 162         if (target_dst != tuple->dst.u.udp.port)
 163                 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
 164                                          offsetof(struct udphdr, dest),
 165                                          0xFFFF, be16_to_cpu(target_dst));
 166 }
 167
 168 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct,
 169                                               enum ip_conntrack_dir dir,
 170                                               struct flow_action *action)
 171 {
 172         struct nf_conn_labels *ct_labels;
 173         struct flow_action_entry *entry;
 174         enum ip_conntrack_info ctinfo;
 175         u32 *act_ct_labels;
 176
 177         entry = tcf_ct_flow_table_flow_action_get_next(action);
 178         entry->id = FLOW_ACTION_CT_METADATA;
 179 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 180         entry->ct_metadata.mark = ct->mark;
 181 #endif
 182         ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
 183                                              IP_CT_ESTABLISHED_REPLY;
 184         /* aligns with the CT reference on the SKB nf_ct_set */
 185         entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
 186         entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL;
 187
 188         act_ct_labels = entry->ct_metadata.labels;
 189         ct_labels = nf_ct_labels_find(ct);
 190         if (ct_labels)
 191                 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
 192         else
 193                 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
 194 }
 195
 196 static int tcf_ct_flow_table_add_action_nat(struct net *net,
 197                                             struct nf_conn *ct,
 198                                             enum ip_conntrack_dir dir,
 199                                             struct flow_action *action)
 200 {
 201         const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
 202         struct nf_conntrack_tuple target;
 203
 204         if (!(ct->status & IPS_NAT_MASK))
 205                 return 0;
 206
 207         nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
 208
 209         switch (tuple->src.l3num) {
 210         case NFPROTO_IPV4:
 211                 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
 212                                                       action);
 213                 break;
 214         case NFPROTO_IPV6:
 215                 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
 216                                                       action);
 217                 break;
 218         default:
 219                 return -EOPNOTSUPP;
 220         }
 221
 222         switch (nf_ct_protonum(ct)) {
 223         case IPPROTO_TCP:
 224                 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
 225                 break;
 226         case IPPROTO_UDP:
 227                 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
 228                 break;
 229         default:
 230                 return -EOPNOTSUPP;
 231         }
 232
 233         return 0;
 234 }
 235
 236 static int tcf_ct_flow_table_fill_actions(struct net *net,
 237                                           const struct flow_offload *flow,
 238                                           enum flow_offload_tuple_dir tdir,
 239                                           struct nf_flow_rule *flow_rule)
 240 {
 241         struct flow_action *action = &flow_rule->rule->action;
 242         int num_entries = action->num_entries;
 243         struct nf_conn *ct = flow->ct;
 244         enum ip_conntrack_dir dir;
 245         int i, err;
 246
 247         switch (tdir) {
 248         case FLOW_OFFLOAD_DIR_ORIGINAL:
 249                 dir = IP_CT_DIR_ORIGINAL;
 250                 break;
 251         case FLOW_OFFLOAD_DIR_REPLY:
 252                 dir = IP_CT_DIR_REPLY;
 253                 break;
 254         default:
 255                 return -EOPNOTSUPP;
 256         }
 257
 258         err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
 259         if (err)
 260                 goto err_nat;
 261
 262         tcf_ct_flow_table_add_action_meta(ct, dir, action);
 263         return 0;
 264
 265 err_nat:
 266         /* Clear filled actions */
 267         for (i = num_entries; i < action->num_entries; i++)
 268                 memset(&action->entries[i], 0, sizeof(action->entries[i]));
 269         action->num_entries = num_entries;
 270
 271         return err;
 272 }
 273
 274 static struct nf_flowtable_type flowtable_ct = {
 275         .action         = tcf_ct_flow_table_fill_actions,
 276         .owner          = THIS_MODULE,
 277 };
 278
 279 static int tcf_ct_flow_table_get(struct tcf_ct_params *params)
 280 {
 281         struct tcf_ct_flow_table *ct_ft;
 282         int err = -ENOMEM;
 283
 284         mutex_lock(&zones_mutex);
 285         ct_ft = rhashtable_lookup_fast(&zones_ht, &params->zone, zones_params);
 286         if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
 287                 goto out_unlock;
 288
 289         ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
 290         if (!ct_ft)
 291                 goto err_alloc;
 292         refcount_set(&ct_ft->ref, 1);
 293
 294         ct_ft->zone = params->zone;
 295         err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
 296         if (err)
 297                 goto err_insert;
 298
 299         ct_ft->nf_ft.type = &flowtable_ct;
 300         ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD |
 301                               NF_FLOWTABLE_COUNTER;
 302         err = nf_flow_table_init(&ct_ft->nf_ft);
 303         if (err)
 304                 goto err_init;
 305
 306         __module_get(THIS_MODULE);
 307 out_unlock:
 308         params->ct_ft = ct_ft;
 309         params->nf_ft = &ct_ft->nf_ft;
 310         mutex_unlock(&zones_mutex);
 311
 312         return 0;
 313
 314 err_init:
 315         rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
 316 err_insert:
 317         kfree(ct_ft);
 318 err_alloc:
 319         mutex_unlock(&zones_mutex);
 320         return err;
 321 }
 322
 323 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
 324 {
 325         struct flow_block_cb *block_cb, *tmp_cb;
 326         struct tcf_ct_flow_table *ct_ft;
 327         struct flow_block *block;
 328
 329         ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
 330                              rwork);
 331         nf_flow_table_free(&ct_ft->nf_ft);
 332
 333         /* Remove any remaining callbacks before cleanup */
 334         block = &ct_ft->nf_ft.flow_block;
 335         down_write(&ct_ft->nf_ft.flow_block_lock);
 336         list_for_each_entry_safe(block_cb, tmp_cb, &block->cb_list, list) {
 337                 list_del(&block_cb->list);
 338                 flow_block_cb_free(block_cb);
 339         }
 340         up_write(&ct_ft->nf_ft.flow_block_lock);
 341         kfree(ct_ft);
 342
 343         module_put(THIS_MODULE);
 344 }
 345
 346 static void tcf_ct_flow_table_put(struct tcf_ct_params *params)
 347 {
 348         struct tcf_ct_flow_table *ct_ft = params->ct_ft;
 349
 350         if (refcount_dec_and_test(&params->ct_ft->ref)) {
 351                 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
 352                 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
 353                 queue_rcu_work(act_ct_wq, &ct_ft->rwork);
 354         }
 355 }
 356
 357 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
 358                                   struct nf_conn *ct,
 359                                   bool tcp)
 360 {
 361         struct flow_offload *entry;
 362         int err;
 363
 364         if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
 365                 return;
 366
 367         entry = flow_offload_alloc(ct);
 368         if (!entry) {
 369                 WARN_ON_ONCE(1);
 370                 goto err_alloc;
 371         }
 372
 373         if (tcp) {
 374                 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
 375                 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
 376         }
 377
 378         err = flow_offload_add(&ct_ft->nf_ft, entry);
 379         if (err)
 380                 goto err_add;
 381
 382         return;
 383
 384 err_add:
 385         flow_offload_free(entry);
 386 err_alloc:
 387         clear_bit(IPS_OFFLOAD_BIT, &ct->status);
 388 }
 389
 390 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
 391                                            struct nf_conn *ct,
 392                                            enum ip_conntrack_info ctinfo)
 393 {
 394         bool tcp = false;
 395
 396         if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
 397                 return;
 398
 399         switch (nf_ct_protonum(ct)) {
 400         case IPPROTO_TCP:
 401                 tcp = true;
 402                 if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
 403                         return;
 404                 break;
 405         case IPPROTO_UDP:
 406                 break;
 407         default:
 408                 return;
 409         }
 410
 411         if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
 412             ct->status & IPS_SEQ_ADJUST)
 413                 return;
 414
 415         tcf_ct_flow_table_add(ct_ft, ct, tcp);
 416 }
 417
 418 static bool
 419 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
 420                                   struct flow_offload_tuple *tuple,
 421                                   struct tcphdr **tcph)
 422 {
 423         struct flow_ports *ports;
 424         unsigned int thoff;
 425         struct iphdr *iph;
 426
 427         if (!pskb_network_may_pull(skb, sizeof(*iph)))
 428                 return false;
 429
 430         iph = ip_hdr(skb);
 431         thoff = iph->ihl * 4;
 432
 433         if (ip_is_fragment(iph) ||
 434             unlikely(thoff != sizeof(struct iphdr)))
 435                 return false;
 436
 437         if (iph->protocol != IPPROTO_TCP &&
 438             iph->protocol != IPPROTO_UDP)
 439                 return false;
 440
 441         if (iph->ttl <= 1)
 442                 return false;
 443
 444         if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ?
 445                                         thoff + sizeof(struct tcphdr) :
 446                                         thoff + sizeof(*ports)))
 447                 return false;
 448
 449         iph = ip_hdr(skb);
 450         if (iph->protocol == IPPROTO_TCP)
 451                 *tcph = (void *)(skb_network_header(skb) + thoff);
 452
 453         ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
 454         tuple->src_v4.s_addr = iph->saddr;
 455         tuple->dst_v4.s_addr = iph->daddr;
 456         tuple->src_port = ports->source;
 457         tuple->dst_port = ports->dest;
 458         tuple->l3proto = AF_INET;
 459         tuple->l4proto = iph->protocol;
 460
 461         return true;
 462 }
 463
 464 static bool
 465 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
 466                                   struct flow_offload_tuple *tuple,
 467                                   struct tcphdr **tcph)
 468 {
 469         struct flow_ports *ports;
 470         struct ipv6hdr *ip6h;
 471         unsigned int thoff;
 472
 473         if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
 474                 return false;
 475
 476         ip6h = ipv6_hdr(skb);
 477
 478         if (ip6h->nexthdr != IPPROTO_TCP &&
 479             ip6h->nexthdr != IPPROTO_UDP)
 480                 return false;
 481
 482         if (ip6h->hop_limit <= 1)
 483                 return false;
 484
 485         thoff = sizeof(*ip6h);
 486         if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ?
 487                                         thoff + sizeof(struct tcphdr) :
 488                                         thoff + sizeof(*ports)))
 489                 return false;
 490
 491         ip6h = ipv6_hdr(skb);
 492         if (ip6h->nexthdr == IPPROTO_TCP)
 493                 *tcph = (void *)(skb_network_header(skb) + thoff);
 494
 495         ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
 496         tuple->src_v6 = ip6h->saddr;
 497         tuple->dst_v6 = ip6h->daddr;
 498         tuple->src_port = ports->source;
 499         tuple->dst_port = ports->dest;
 500         tuple->l3proto = AF_INET6;
 501         tuple->l4proto = ip6h->nexthdr;
 502
 503         return true;
 504 }
 505
 506 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
 507                                      struct sk_buff *skb,
 508                                      u8 family)
 509 {
 510         struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
 511         struct flow_offload_tuple_rhash *tuplehash;
 512         struct flow_offload_tuple tuple = {};
 513         enum ip_conntrack_info ctinfo;
 514         struct tcphdr *tcph = NULL;
 515         struct flow_offload *flow;
 516         struct nf_conn *ct;
 517         u8 dir;
 518
 519         /* Previously seen or loopback */
 520         ct = nf_ct_get(skb, &ctinfo);
 521         if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
 522                 return false;
 523
 524         switch (family) {
 525         case NFPROTO_IPV4:
 526                 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
 527                         return false;
 528                 break;
 529         case NFPROTO_IPV6:
 530                 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
 531                         return false;
 532                 break;
 533         default:
 534                 return false;
 535         }
 536
 537         tuplehash = flow_offload_lookup(nf_ft, &tuple);
 538         if (!tuplehash)
 539                 return false;
 540
 541         dir = tuplehash->tuple.dir;
 542         flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
 543         ct = flow->ct;
 544
 545         if (tcph && (unlikely(tcph->fin || tcph->rst))) {
 546                 flow_offload_teardown(flow);
 547                 return false;
 548         }
 549
 550         ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
 551                                                     IP_CT_ESTABLISHED_REPLY;
 552
 553         flow_offload_refresh(nf_ft, flow);
 554         nf_conntrack_get(&ct->ct_general);
 555         nf_ct_set(skb, ct, ctinfo);
 556         if (nf_ft->flags & NF_FLOWTABLE_COUNTER)
 557                 nf_ct_acct_update(ct, dir, skb->len);
 558
 559         return true;
 560 }
 561
 562 static int tcf_ct_flow_tables_init(void)
 563 {
 564         return rhashtable_init(&zones_ht, &zones_params);
 565 }
 566
 567 static void tcf_ct_flow_tables_uninit(void)
 568 {
 569         rhashtable_destroy(&zones_ht);
 570 }
 571
 572 static struct tc_action_ops act_ct_ops;
 573 static unsigned int ct_net_id;
 574
 575 struct tc_ct_action_net {
 576         struct tc_action_net tn; /* Must be first */
 577         bool labels;
 578 };
 579
 580 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
 581 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
 582                                    u16 zone_id, bool force)
 583 {
 584         enum ip_conntrack_info ctinfo;
 585         struct nf_conn *ct;
 586
 587         ct = nf_ct_get(skb, &ctinfo);
 588         if (!ct)
 589                 return false;
 590         if (!net_eq(net, read_pnet(&ct->ct_net)))
 591                 return false;
 592         if (nf_ct_zone(ct)->id != zone_id)
 593                 return false;
 594
 595         /* Force conntrack entry direction. */
 596         if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
 597                 if (nf_ct_is_confirmed(ct))
 598                         nf_ct_kill(ct);
 599
 600                 nf_conntrack_put(&ct->ct_general);
 601                 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
 602
 603                 return false;
 604         }
 605
 606         return true;
 607 }
 608
 609 /* Trim the skb to the length specified by the IP/IPv6 header,
 610  * removing any trailing lower-layer padding. This prepares the skb
 611  * for higher-layer processing that assumes skb->len excludes padding
 612  * (such as nf_ip_checksum). The caller needs to pull the skb to the
 613  * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
 614  */
 615 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
 616 {
 617         unsigned int len;
 618         int err;
 619
 620         switch (family) {
 621         case NFPROTO_IPV4:
 622                 len = ntohs(ip_hdr(skb)->tot_len);
 623                 break;
 624         case NFPROTO_IPV6:
 625                 len = sizeof(struct ipv6hdr)
 626                         + ntohs(ipv6_hdr(skb)->payload_len);
 627                 break;
 628         default:
 629                 len = skb->len;
 630         }
 631
 632         err = pskb_trim_rcsum(skb, len);
 633
 634         return err;
 635 }
 636
 637 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
 638 {
 639         u8 family = NFPROTO_UNSPEC;
 640
 641         switch (skb_protocol(skb, true)) {
 642         case htons(ETH_P_IP):
 643                 family = NFPROTO_IPV4;
 644                 break;
 645         case htons(ETH_P_IPV6):
 646                 family = NFPROTO_IPV6;
 647                 break;
 648         default:
 649                 break;
 650         }
 651
 652         return family;
 653 }
 654
 655 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
 656 {
 657         unsigned int len;
 658
 659         len =  skb_network_offset(skb) + sizeof(struct iphdr);
 660         if (unlikely(skb->len < len))
 661                 return -EINVAL;
 662         if (unlikely(!pskb_may_pull(skb, len)))
 663                 return -ENOMEM;
 664
 665         *frag = ip_is_fragment(ip_hdr(skb));
 666         return 0;
 667 }
 668
 669 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
 670 {
 671         unsigned int flags = 0, len, payload_ofs = 0;
 672         unsigned short frag_off;
 673         int nexthdr;
 674
 675         len =  skb_network_offset(skb) + sizeof(struct ipv6hdr);
 676         if (unlikely(skb->len < len))
 677                 return -EINVAL;
 678         if (unlikely(!pskb_may_pull(skb, len)))
 679                 return -ENOMEM;
 680
 681         nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
 682         if (unlikely(nexthdr < 0))
 683                 return -EPROTO;
 684
 685         *frag = flags & IP6_FH_F_FRAG;
 686         return 0;
 687 }
 688
 689 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
 690                                    u8 family, u16 zone, bool *defrag)
 691 {
 692         enum ip_conntrack_info ctinfo;
 693         struct qdisc_skb_cb cb;
 694         struct nf_conn *ct;
 695         int err = 0;
 696         bool frag;
 697
 698         /* Previously seen (loopback)? Ignore. */
 699         ct = nf_ct_get(skb, &ctinfo);
 700         if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
 701                 return 0;
 702
 703         if (family == NFPROTO_IPV4)
 704                 err = tcf_ct_ipv4_is_fragment(skb, &frag);
 705         else
 706                 err = tcf_ct_ipv6_is_fragment(skb, &frag);
 707         if (err || !frag)
 708                 return err;
 709
 710         skb_get(skb);
 711         cb = *qdisc_skb_cb(skb);
 712
 713         if (family == NFPROTO_IPV4) {
 714                 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
 715
 716                 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 717                 local_bh_disable();
 718                 err = ip_defrag(net, skb, user);
 719                 local_bh_enable();
 720                 if (err && err != -EINPROGRESS)
 721                         return err;
 722
 723                 if (!err) {
 724                         *defrag = true;
 725                         cb.mru = IPCB(skb)->frag_max_size;
 726                 }
 727         } else { /* NFPROTO_IPV6 */
 728 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
 729                 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
 730
 731                 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
 732                 err = nf_ct_frag6_gather(net, skb, user);
 733                 if (err && err != -EINPROGRESS)
 734                         goto out_free;
 735
 736                 if (!err) {
 737                         *defrag = true;
 738                         cb.mru = IP6CB(skb)->frag_max_size;
 739                 }
 740 #else
 741                 err = -EOPNOTSUPP;
 742                 goto out_free;
 743 #endif
 744         }
 745
 746         if (err != -EINPROGRESS)
 747                 *qdisc_skb_cb(skb) = cb;
 748         skb_clear_hash(skb);
 749         skb->ignore_df = 1;
 750         return err;
 751
 752 out_free:
 753         kfree_skb(skb);
 754         return err;
 755 }
 756
 757 static void tcf_ct_params_free(struct rcu_head *head)
 758 {
 759         struct tcf_ct_params *params = container_of(head,
 760                                                     struct tcf_ct_params, rcu);
 761
 762         tcf_ct_flow_table_put(params);
 763
 764         if (params->tmpl)
 765                 nf_conntrack_put(&params->tmpl->ct_general);
 766         kfree(params);
 767 }
 768
 769 #if IS_ENABLED(CONFIG_NF_NAT)
 770 /* Modelled after nf_nat_ipv[46]_fn().
 771  * range is only used for new, uninitialized NAT state.
 772  * Returns either NF_ACCEPT or NF_DROP.
 773  */
 774 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
 775                           enum ip_conntrack_info ctinfo,
 776                           const struct nf_nat_range2 *range,
 777                           enum nf_nat_manip_type maniptype)
 778 {
 779         __be16 proto = skb_protocol(skb, true);
 780         int hooknum, err = NF_ACCEPT;
 781
 782         /* See HOOK2MANIP(). */
 783         if (maniptype == NF_NAT_MANIP_SRC)
 784                 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
 785         else
 786                 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
 787
 788         switch (ctinfo) {
 789         case IP_CT_RELATED:
 790         case IP_CT_RELATED_REPLY:
 791                 if (proto == htons(ETH_P_IP) &&
 792                     ip_hdr(skb)->protocol == IPPROTO_ICMP) {
 793                         if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
 794                                                            hooknum))
 795                                 err = NF_DROP;
 796                         goto out;
 797                 } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) {
 798                         __be16 frag_off;
 799                         u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 800                         int hdrlen = ipv6_skip_exthdr(skb,
 801                                                       sizeof(struct ipv6hdr),
 802                                                       &nexthdr, &frag_off);
 803
 804                         if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
 805                                 if (!nf_nat_icmpv6_reply_translation(skb, ct,
 806                                                                      ctinfo,
 807                                                                      hooknum,
 808                                                                      hdrlen))
 809                                         err = NF_DROP;
 810                                 goto out;
 811                         }
 812                 }
 813                 /* Non-ICMP, fall thru to initialize if needed. */
 814                 fallthrough;
 815         case IP_CT_NEW:
 816                 /* Seen it before?  This can happen for loopback, retrans,
 817                  * or local packets.
 818                  */
 819                 if (!nf_nat_initialized(ct, maniptype)) {
 820                         /* Initialize according to the NAT action. */
 821                         err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
 822                                 /* Action is set up to establish a new
 823                                  * mapping.
 824                                  */
 825                                 ? nf_nat_setup_info(ct, range, maniptype)
 826                                 : nf_nat_alloc_null_binding(ct, hooknum);
 827                         if (err != NF_ACCEPT)
 828                                 goto out;
 829                 }
 830                 break;
 831
 832         case IP_CT_ESTABLISHED:
 833         case IP_CT_ESTABLISHED_REPLY:
 834                 break;
 835
 836         default:
 837                 err = NF_DROP;
 838                 goto out;
 839         }
 840
 841         err = nf_nat_packet(ct, ctinfo, hooknum, skb);
 842 out:
 843         return err;
 844 }
 845 #endif /* CONFIG_NF_NAT */
 846
 847 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
 848 {
 849 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 850         u32 new_mark;
 851
 852         if (!mask)
 853                 return;
 854
 855         new_mark = mark | (ct->mark & ~(mask));
 856         if (ct->mark != new_mark) {
 857                 ct->mark = new_mark;
 858                 if (nf_ct_is_confirmed(ct))
 859                         nf_conntrack_event_cache(IPCT_MARK, ct);
 860         }
 861 #endif
 862 }
 863
 864 static void tcf_ct_act_set_labels(struct nf_conn *ct,
 865                                   u32 *labels,
 866                                   u32 *labels_m)
 867 {
 868 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
 869         size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
 870
 871         if (!memchr_inv(labels_m, 0, labels_sz))
 872                 return;
 873
 874         nf_connlabels_replace(ct, labels, labels_m, 4);
 875 #endif
 876 }
 877
 878 static int tcf_ct_act_nat(struct sk_buff *skb,
 879                           struct nf_conn *ct,
 880                           enum ip_conntrack_info ctinfo,
 881                           int ct_action,
 882                           struct nf_nat_range2 *range,
 883                           bool commit)
 884 {
 885 #if IS_ENABLED(CONFIG_NF_NAT)
 886         int err;
 887         enum nf_nat_manip_type maniptype;
 888
 889         if (!(ct_action & TCA_CT_ACT_NAT))
 890                 return NF_ACCEPT;
 891
 892         /* Add NAT extension if not confirmed yet. */
 893         if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
 894                 return NF_DROP;   /* Can't NAT. */
 895
 896         if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) &&
 897             (ctinfo != IP_CT_RELATED || commit)) {
 898                 /* NAT an established or related connection like before. */
 899                 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
 900                         /* This is the REPLY direction for a connection
 901                          * for which NAT was applied in the forward
 902                          * direction.  Do the reverse NAT.
 903                          */
 904                         maniptype = ct->status & IPS_SRC_NAT
 905                                 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
 906                 else
 907                         maniptype = ct->status & IPS_SRC_NAT
 908                                 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
 909         } else if (ct_action & TCA_CT_ACT_NAT_SRC) {
 910                 maniptype = NF_NAT_MANIP_SRC;
 911         } else if (ct_action & TCA_CT_ACT_NAT_DST) {
 912                 maniptype = NF_NAT_MANIP_DST;
 913         } else {
 914                 return NF_ACCEPT;
 915         }
 916
 917         err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
 918         if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) {
 919                 if (ct->status & IPS_SRC_NAT) {
 920                         if (maniptype == NF_NAT_MANIP_SRC)
 921                                 maniptype = NF_NAT_MANIP_DST;
 922                         else
 923                                 maniptype = NF_NAT_MANIP_SRC;
 924
 925                         err = ct_nat_execute(skb, ct, ctinfo, range,
 926                                              maniptype);
 927                 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) {
 928                         err = ct_nat_execute(skb, ct, ctinfo, NULL,
 929                                              NF_NAT_MANIP_SRC);
 930                 }
 931         }
 932         return err;
 933 #else
 934         return NF_ACCEPT;
 935 #endif
 936 }
 937
 938 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
 939                       struct tcf_result *res)
 940 {
 941         struct net *net = dev_net(skb->dev);
 942         bool cached, commit, clear, force;
 943         enum ip_conntrack_info ctinfo;
 944         struct tcf_ct *c = to_ct(a);
 945         struct nf_conn *tmpl = NULL;
 946         struct nf_hook_state state;
 947         int nh_ofs, err, retval;
 948         struct tcf_ct_params *p;
 949         bool skip_add = false;
 950         bool defrag = false;
 951         struct nf_conn *ct;
 952         u8 family;
 953
 954         p = rcu_dereference_bh(c->params);
 955
 956         retval = READ_ONCE(c->tcf_action);
 957         commit = p->ct_action & TCA_CT_ACT_COMMIT;
 958         clear = p->ct_action & TCA_CT_ACT_CLEAR;
 959         force = p->ct_action & TCA_CT_ACT_FORCE;
 960         tmpl = p->tmpl;
 961
 962         tcf_lastuse_update(&c->tcf_tm);
 963
 964         if (clear) {
 965                 qdisc_skb_cb(skb)->post_ct = false;
 966                 ct = nf_ct_get(skb, &ctinfo);
 967                 if (ct) {
 968                         nf_conntrack_put(&ct->ct_general);
 969                         nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
 970                 }
 971
 972                 goto out_clear;
 973         }
 974
 975         family = tcf_ct_skb_nf_family(skb);
 976         if (family == NFPROTO_UNSPEC)
 977                 goto drop;
 978
 979         /* The conntrack module expects to be working at L3.
 980          * We also try to pull the IPv4/6 header to linear area
 981          */
 982         nh_ofs = skb_network_offset(skb);
 983         skb_pull_rcsum(skb, nh_ofs);
 984         err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
 985         if (err == -EINPROGRESS) {
 986                 retval = TC_ACT_STOLEN;
 987                 goto out_clear;
 988         }
 989         if (err)
 990                 goto drop;
 991
 992         err = tcf_ct_skb_network_trim(skb, family);
 993         if (err)
 994                 goto drop;
 995
 996         /* If we are recirculating packets to match on ct fields and
 997          * committing with a separate ct action, then we don't need to
 998          * actually run the packet through conntrack twice unless it's for a
 999          * different zone.
1000          */
1001         cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);
1002         if (!cached) {
1003                 if (tcf_ct_flow_table_lookup(p, skb, family)) {
1004                         skip_add = true;
1005                         goto do_nat;
1006                 }
1007
1008                 /* Associate skb with specified zone. */
1009                 if (tmpl) {
1010                         nf_conntrack_put(skb_nfct(skb));
1011                         nf_conntrack_get(&tmpl->ct_general);
1012                         nf_ct_set(skb, tmpl, IP_CT_NEW);
1013                 }
1014
1015                 state.hook = NF_INET_PRE_ROUTING;
1016                 state.net = net;
1017                 state.pf = family;
1018                 err = nf_conntrack_in(skb, &state);
1019                 if (err != NF_ACCEPT)
1020                         goto out_push;
1021         }
1022
1023 do_nat:
1024         ct = nf_ct_get(skb, &ctinfo);
1025         if (!ct)
1026                 goto out_push;
1027         nf_ct_deliver_cached_events(ct);
1028
1029         err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1030         if (err != NF_ACCEPT)
1031                 goto drop;
1032
1033         if (commit) {
1034                 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1035                 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1036
1037                 /* This will take care of sending queued events
1038                  * even if the connection is already confirmed.
1039                  */
1040                 if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1041                         goto drop;
1042         }
1043
1044         if (!skip_add)
1045                 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1046
1047 out_push:
1048         skb_push_rcsum(skb, nh_ofs);
1049
1050         qdisc_skb_cb(skb)->post_ct = true;
1051 out_clear:
1052         tcf_action_update_bstats(&c->common, skb);
1053         if (defrag)
1054                 qdisc_skb_cb(skb)->pkt_len = skb->len;
1055         return retval;
1056
1057 drop:
1058         tcf_action_inc_drop_qstats(&c->common);
1059         return TC_ACT_SHOT;
1060 }
1061
1062 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1063         [TCA_CT_ACTION] = { .type = NLA_U16 },
1064         [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)),
1065         [TCA_CT_ZONE] = { .type = NLA_U16 },
1066         [TCA_CT_MARK] = { .type = NLA_U32 },
1067         [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1068         [TCA_CT_LABELS] = { .type = NLA_BINARY,
1069                             .len = 128 / BITS_PER_BYTE },
1070         [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1071                                  .len = 128 / BITS_PER_BYTE },
1072         [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1073         [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1074         [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1075         [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1076         [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1077         [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1078 };
1079
1080 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1081                                   struct tc_ct *parm,
1082                                   struct nlattr **tb,
1083                                   struct netlink_ext_ack *extack)
1084 {
1085         struct nf_nat_range2 *range;
1086
1087         if (!(p->ct_action & TCA_CT_ACT_NAT))
1088                 return 0;
1089
1090         if (!IS_ENABLED(CONFIG_NF_NAT)) {
1091                 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1092                 return -EOPNOTSUPP;
1093         }
1094
1095         if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1096                 return 0;
1097
1098         if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1099             (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1100                 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1101                 return -EOPNOTSUPP;
1102         }
1103
1104         range = &p->range;
1105         if (tb[TCA_CT_NAT_IPV4_MIN]) {
1106                 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1107
1108                 p->ipv4_range = true;
1109                 range->flags |= NF_NAT_RANGE_MAP_IPS;
1110                 range->min_addr.ip =
1111                         nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1112
1113                 range->max_addr.ip = max_attr ?
1114                                      nla_get_in_addr(max_attr) :
1115                                      range->min_addr.ip;
1116         } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1117                 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1118
1119                 p->ipv4_range = false;
1120                 range->flags |= NF_NAT_RANGE_MAP_IPS;
1121                 range->min_addr.in6 =
1122                         nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1123
1124                 range->max_addr.in6 = max_attr ?
1125                                       nla_get_in6_addr(max_attr) :
1126                                       range->min_addr.in6;
1127         }
1128
1129         if (tb[TCA_CT_NAT_PORT_MIN]) {
1130                 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1131                 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1132
1133                 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1134                                        nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1135                                        range->min_proto.all;
1136         }
1137
1138         return 0;
1139 }
1140
1141 static void tcf_ct_set_key_val(struct nlattr **tb,
1142                                void *val, int val_type,
1143                                void *mask, int mask_type,
1144                                int len)
1145 {
1146         if (!tb[val_type])
1147                 return;
1148         nla_memcpy(val, tb[val_type], len);
1149
1150         if (!mask)
1151                 return;
1152
1153         if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1154                 memset(mask, 0xff, len);
1155         else
1156                 nla_memcpy(mask, tb[mask_type], len);
1157 }
1158
1159 static int tcf_ct_fill_params(struct net *net,
1160                               struct tcf_ct_params *p,
1161                               struct tc_ct *parm,
1162                               struct nlattr **tb,
1163                               struct netlink_ext_ack *extack)
1164 {
1165         struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1166         struct nf_conntrack_zone zone;
1167         struct nf_conn *tmpl;
1168         int err;
1169
1170         p->zone = NF_CT_DEFAULT_ZONE_ID;
1171
1172         tcf_ct_set_key_val(tb,
1173                            &p->ct_action, TCA_CT_ACTION,
1174                            NULL, TCA_CT_UNSPEC,
1175                            sizeof(p->ct_action));
1176
1177         if (p->ct_action & TCA_CT_ACT_CLEAR)
1178                 return 0;
1179
1180         err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1181         if (err)
1182                 return err;
1183
1184         if (tb[TCA_CT_MARK]) {
1185                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1186                         NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1187                         return -EOPNOTSUPP;
1188                 }
1189                 tcf_ct_set_key_val(tb,
1190                                    &p->mark, TCA_CT_MARK,
1191                                    &p->mark_mask, TCA_CT_MARK_MASK,
1192                                    sizeof(p->mark));
1193         }
1194
1195         if (tb[TCA_CT_LABELS]) {
1196                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1197                         NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1198                         return -EOPNOTSUPP;
1199                 }
1200
1201                 if (!tn->labels) {
1202                         NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1203                         return -EOPNOTSUPP;
1204                 }
1205                 tcf_ct_set_key_val(tb,
1206                                    p->labels, TCA_CT_LABELS,
1207                                    p->labels_mask, TCA_CT_LABELS_MASK,
1208                                    sizeof(p->labels));
1209         }
1210
1211         if (tb[TCA_CT_ZONE]) {
1212                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1213                         NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1214                         return -EOPNOTSUPP;
1215                 }
1216
1217                 tcf_ct_set_key_val(tb,
1218                                    &p->zone, TCA_CT_ZONE,
1219                                    NULL, TCA_CT_UNSPEC,
1220                                    sizeof(p->zone));
1221         }
1222
1223         nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1224         tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1225         if (!tmpl) {
1226                 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1227                 return -ENOMEM;
1228         }
1229         __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1230         nf_conntrack_get(&tmpl->ct_general);
1231         p->tmpl = tmpl;
1232
1233         return 0;
1234 }
1235
1236 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1237                        struct nlattr *est, struct tc_action **a,
1238                        int replace, int bind, bool rtnl_held,
1239                        struct tcf_proto *tp, u32 flags,
1240                        struct netlink_ext_ack *extack)
1241 {
1242         struct tc_action_net *tn = net_generic(net, ct_net_id);
1243         struct tcf_ct_params *params = NULL;
1244         struct nlattr *tb[TCA_CT_MAX + 1];
1245         struct tcf_chain *goto_ch = NULL;
1246         struct tc_ct *parm;
1247         struct tcf_ct *c;
1248         int err, res = 0;
1249         u32 index;
1250
1251         if (!nla) {
1252                 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1253                 return -EINVAL;
1254         }
1255
1256         err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1257         if (err < 0)
1258                 return err;
1259
1260         if (!tb[TCA_CT_PARMS]) {
1261                 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1262                 return -EINVAL;
1263         }
1264         parm = nla_data(tb[TCA_CT_PARMS]);
1265         index = parm->index;
1266         err = tcf_idr_check_alloc(tn, &index, a, bind);
1267         if (err < 0)
1268                 return err;
1269
1270         if (!err) {
1271                 err = tcf_idr_create_from_flags(tn, index, est, a,
1272                                                 &act_ct_ops, bind, flags);
1273                 if (err) {
1274                         tcf_idr_cleanup(tn, index);
1275                         return err;
1276                 }
1277                 res = ACT_P_CREATED;
1278         } else {
1279                 if (bind)
1280                         return 0;
1281
1282                 if (!replace) {
1283                         tcf_idr_release(*a, bind);
1284                         return -EEXIST;
1285                 }
1286         }
1287         err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1288         if (err < 0)
1289                 goto cleanup;
1290
1291         c = to_ct(*a);
1292
1293         params = kzalloc(sizeof(*params), GFP_KERNEL);
1294         if (unlikely(!params)) {
1295                 err = -ENOMEM;
1296                 goto cleanup;
1297         }
1298
1299         err = tcf_ct_fill_params(net, params, parm, tb, extack);
1300         if (err)
1301                 goto cleanup;
1302
1303         err = tcf_ct_flow_table_get(params);
1304         if (err)
1305                 goto cleanup;
1306
1307         spin_lock_bh(&c->tcf_lock);
1308         goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1309         params = rcu_replace_pointer(c->params, params,
1310                                      lockdep_is_held(&c->tcf_lock));
1311         spin_unlock_bh(&c->tcf_lock);
1312
1313         if (goto_ch)
1314                 tcf_chain_put_by_act(goto_ch);
1315         if (params)
1316                 call_rcu(&params->rcu, tcf_ct_params_free);
1317
1318         return res;
1319
1320 cleanup:
1321         if (goto_ch)
1322                 tcf_chain_put_by_act(goto_ch);
1323         kfree(params);
1324         tcf_idr_release(*a, bind);
1325         return err;
1326 }
1327
1328 static void tcf_ct_cleanup(struct tc_action *a)
1329 {
1330         struct tcf_ct_params *params;
1331         struct tcf_ct *c = to_ct(a);
1332
1333         params = rcu_dereference_protected(c->params, 1);
1334         if (params)
1335                 call_rcu(&params->rcu, tcf_ct_params_free);
1336 }
1337
1338 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1339                                void *val, int val_type,
1340                                void *mask, int mask_type,
1341                                int len)
1342 {
1343         int err;
1344
1345         if (mask && !memchr_inv(mask, 0, len))
1346                 return 0;
1347
1348         err = nla_put(skb, val_type, len, val);
1349         if (err)
1350                 return err;
1351
1352         if (mask_type != TCA_CT_UNSPEC) {
1353                 err = nla_put(skb, mask_type, len, mask);
1354                 if (err)
1355                         return err;
1356         }
1357
1358         return 0;
1359 }
1360
1361 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1362 {
1363         struct nf_nat_range2 *range = &p->range;
1364
1365         if (!(p->ct_action & TCA_CT_ACT_NAT))
1366                 return 0;
1367
1368         if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1369                 return 0;
1370
1371         if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1372                 if (p->ipv4_range) {
1373                         if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1374                                             range->min_addr.ip))
1375                                 return -1;
1376                         if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1377                                             range->max_addr.ip))
1378                                 return -1;
1379                 } else {
1380                         if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1381                                              &range->min_addr.in6))
1382                                 return -1;
1383                         if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1384                                              &range->max_addr.in6))
1385                                 return -1;
1386                 }
1387         }
1388
1389         if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1390                 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1391                                  range->min_proto.all))
1392                         return -1;
1393                 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1394                                  range->max_proto.all))
1395                         return -1;
1396         }
1397
1398         return 0;
1399 }
1400
1401 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1402                               int bind, int ref)
1403 {
1404         unsigned char *b = skb_tail_pointer(skb);
1405         struct tcf_ct *c = to_ct(a);
1406         struct tcf_ct_params *p;
1407
1408         struct tc_ct opt = {
1409                 .index   = c->tcf_index,
1410                 .refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1411                 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1412         };
1413         struct tcf_t t;
1414
1415         spin_lock_bh(&c->tcf_lock);
1416         p = rcu_dereference_protected(c->params,
1417                                       lockdep_is_held(&c->tcf_lock));
1418         opt.action = c->tcf_action;
1419
1420         if (tcf_ct_dump_key_val(skb,
1421                                 &p->ct_action, TCA_CT_ACTION,
1422                                 NULL, TCA_CT_UNSPEC,
1423                                 sizeof(p->ct_action)))
1424                 goto nla_put_failure;
1425
1426         if (p->ct_action & TCA_CT_ACT_CLEAR)
1427                 goto skip_dump;
1428
1429         if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1430             tcf_ct_dump_key_val(skb,
1431                                 &p->mark, TCA_CT_MARK,
1432                                 &p->mark_mask, TCA_CT_MARK_MASK,
1433                                 sizeof(p->mark)))
1434                 goto nla_put_failure;
1435
1436         if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1437             tcf_ct_dump_key_val(skb,
1438                                 p->labels, TCA_CT_LABELS,
1439                                 p->labels_mask, TCA_CT_LABELS_MASK,
1440                                 sizeof(p->labels)))
1441                 goto nla_put_failure;
1442
1443         if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1444             tcf_ct_dump_key_val(skb,
1445                                 &p->zone, TCA_CT_ZONE,
1446                                 NULL, TCA_CT_UNSPEC,
1447                                 sizeof(p->zone)))
1448                 goto nla_put_failure;
1449
1450         if (tcf_ct_dump_nat(skb, p))
1451                 goto nla_put_failure;
1452
1453 skip_dump:
1454         if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1455                 goto nla_put_failure;
1456
1457         tcf_tm_dump(&t, &c->tcf_tm);
1458         if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1459                 goto nla_put_failure;
1460         spin_unlock_bh(&c->tcf_lock);
1461
1462         return skb->len;
1463 nla_put_failure:
1464         spin_unlock_bh(&c->tcf_lock);
1465         nlmsg_trim(skb, b);
1466         return -1;
1467 }
1468
1469 static int tcf_ct_walker(struct net *net, struct sk_buff *skb,
1470                          struct netlink_callback *cb, int type,
1471                          const struct tc_action_ops *ops,
1472                          struct netlink_ext_ack *extack)
1473 {
1474         struct tc_action_net *tn = net_generic(net, ct_net_id);
1475
1476         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
1477 }
1478
1479 static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index)
1480 {
1481         struct tc_action_net *tn = net_generic(net, ct_net_id);
1482
1483         return tcf_idr_search(tn, a, index);
1484 }
1485
1486 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1487                              u64 drops, u64 lastuse, bool hw)
1488 {
1489         struct tcf_ct *c = to_ct(a);
1490
1491         tcf_action_update_stats(a, bytes, packets, drops, hw);
1492         c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1493 }
1494
1495 static struct tc_action_ops act_ct_ops = {
1496         .kind           =       "ct",
1497         .id             =       TCA_ID_CT,
1498         .owner          =       THIS_MODULE,
1499         .act            =       tcf_ct_act,
1500         .dump           =       tcf_ct_dump,
1501         .init           =       tcf_ct_init,
1502         .cleanup        =       tcf_ct_cleanup,
1503         .walk           =       tcf_ct_walker,
1504         .lookup         =       tcf_ct_search,
1505         .stats_update   =       tcf_stats_update,
1506         .size           =       sizeof(struct tcf_ct),
1507 };
1508
1509 static __net_init int ct_init_net(struct net *net)
1510 {
1511         unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1512         struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1513
1514         if (nf_connlabels_get(net, n_bits - 1)) {
1515                 tn->labels = false;
1516                 pr_err("act_ct: Failed to set connlabels length");
1517         } else {
1518                 tn->labels = true;
1519         }
1520
1521         return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1522 }
1523
1524 static void __net_exit ct_exit_net(struct list_head *net_list)
1525 {
1526         struct net *net;
1527
1528         rtnl_lock();
1529         list_for_each_entry(net, net_list, exit_list) {
1530                 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1531
1532                 if (tn->labels)
1533                         nf_connlabels_put(net);
1534         }
1535         rtnl_unlock();
1536
1537         tc_action_net_exit(net_list, ct_net_id);
1538 }
1539
1540 static struct pernet_operations ct_net_ops = {
1541         .init = ct_init_net,
1542         .exit_batch = ct_exit_net,
1543         .id   = &ct_net_id,
1544         .size = sizeof(struct tc_ct_action_net),
1545 };
1546
1547 static int __init ct_init_module(void)
1548 {
1549         int err;
1550
1551         act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1552         if (!act_ct_wq)
1553                 return -ENOMEM;
1554
1555         err = tcf_ct_flow_tables_init();
1556         if (err)
1557                 goto err_tbl_init;
1558
1559         err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1560         if (err)
1561                 goto err_register;
1562
1563         static_branch_inc(&tcf_frag_xmit_count);
1564
1565         return 0;
1566
1567 err_register:
1568         tcf_ct_flow_tables_uninit();
1569 err_tbl_init:
1570         destroy_workqueue(act_ct_wq);
1571         return err;
1572 }
1573
1574 static void __exit ct_cleanup_module(void)
1575 {
1576         static_branch_dec(&tcf_frag_xmit_count);
1577         tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1578         tcf_ct_flow_tables_uninit();
1579         destroy_workqueue(act_ct_wq);
1580 }
1581
1582 module_init(ct_init_module);
1583 module_exit(ct_cleanup_module);
1584 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1585 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1586 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1587 MODULE_DESCRIPTION("Connection tracking action");
1588 MODULE_LICENSE("GPL v2");