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