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