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 <net/netlink.h>
  19 #include <net/pkt_sched.h>
  20 #include <net/pkt_cls.h>
  21 #include <net/act_api.h>
  22 #include <net/ip.h>
  23 #include <net/ipv6_frag.h>
  24 #include <uapi/linux/tc_act/tc_ct.h>
  25 #include <net/tc_act/tc_ct.h>
  26
  27 #include <net/netfilter/nf_conntrack.h>
  28 #include <net/netfilter/nf_conntrack_core.h>
  29 #include <net/netfilter/nf_conntrack_zones.h>
  30 #include <net/netfilter/nf_conntrack_helper.h>
  31 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
  32 #include <uapi/linux/netfilter/nf_nat.h>
  33
  34 static struct tc_action_ops act_ct_ops;
  35 static unsigned int ct_net_id;
  36
  37 struct tc_ct_action_net {
  38         struct tc_action_net tn; /* Must be first */
  39         bool labels;
  40 };
  41
  42 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
  43 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
  44                                    u16 zone_id, bool force)
  45 {
  46         enum ip_conntrack_info ctinfo;
  47         struct nf_conn *ct;
  48
  49         ct = nf_ct_get(skb, &ctinfo);
  50         if (!ct)
  51                 return false;
  52         if (!net_eq(net, read_pnet(&ct->ct_net)))
  53                 return false;
  54         if (nf_ct_zone(ct)->id != zone_id)
  55                 return false;
  56
  57         /* Force conntrack entry direction. */
  58         if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
  59                 if (nf_ct_is_confirmed(ct))
  60                         nf_ct_kill(ct);
  61
  62                 nf_conntrack_put(&ct->ct_general);
  63                 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
  64
  65                 return false;
  66         }
  67
  68         return true;
  69 }
  70
  71 /* Trim the skb to the length specified by the IP/IPv6 header,
  72  * removing any trailing lower-layer padding. This prepares the skb
  73  * for higher-layer processing that assumes skb->len excludes padding
  74  * (such as nf_ip_checksum). The caller needs to pull the skb to the
  75  * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
  76  */
  77 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
  78 {
  79         unsigned int len;
  80         int err;
  81
  82         switch (family) {
  83         case NFPROTO_IPV4:
  84                 len = ntohs(ip_hdr(skb)->tot_len);
  85                 break;
  86         case NFPROTO_IPV6:
  87                 len = sizeof(struct ipv6hdr)
  88                         + ntohs(ipv6_hdr(skb)->payload_len);
  89                 break;
  90         default:
  91                 len = skb->len;
  92         }
  93
  94         err = pskb_trim_rcsum(skb, len);
  95
  96         return err;
  97 }
  98
  99 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
 100 {
 101         u8 family = NFPROTO_UNSPEC;
 102
 103         switch (skb->protocol) {
 104         case htons(ETH_P_IP):
 105                 family = NFPROTO_IPV4;
 106                 break;
 107         case htons(ETH_P_IPV6):
 108                 family = NFPROTO_IPV6;
 109                 break;
 110         default:
 111                 break;
 112         }
 113
 114         return family;
 115 }
 116
 117 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
 118 {
 119         unsigned int len;
 120
 121         len =  skb_network_offset(skb) + sizeof(struct iphdr);
 122         if (unlikely(skb->len < len))
 123                 return -EINVAL;
 124         if (unlikely(!pskb_may_pull(skb, len)))
 125                 return -ENOMEM;
 126
 127         *frag = ip_is_fragment(ip_hdr(skb));
 128         return 0;
 129 }
 130
 131 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
 132 {
 133         unsigned int flags = 0, len, payload_ofs = 0;
 134         unsigned short frag_off;
 135         int nexthdr;
 136
 137         len =  skb_network_offset(skb) + sizeof(struct ipv6hdr);
 138         if (unlikely(skb->len < len))
 139                 return -EINVAL;
 140         if (unlikely(!pskb_may_pull(skb, len)))
 141                 return -ENOMEM;
 142
 143         nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
 144         if (unlikely(nexthdr < 0))
 145                 return -EPROTO;
 146
 147         *frag = flags & IP6_FH_F_FRAG;
 148         return 0;
 149 }
 150
 151 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
 152                                    u8 family, u16 zone)
 153 {
 154         enum ip_conntrack_info ctinfo;
 155         struct nf_conn *ct;
 156         int err = 0;
 157         bool frag;
 158
 159         /* Previously seen (loopback)? Ignore. */
 160         ct = nf_ct_get(skb, &ctinfo);
 161         if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
 162                 return 0;
 163
 164         if (family == NFPROTO_IPV4)
 165                 err = tcf_ct_ipv4_is_fragment(skb, &frag);
 166         else
 167                 err = tcf_ct_ipv6_is_fragment(skb, &frag);
 168         if (err || !frag)
 169                 return err;
 170
 171         skb_get(skb);
 172
 173         if (family == NFPROTO_IPV4) {
 174                 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
 175
 176                 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 177                 local_bh_disable();
 178                 err = ip_defrag(net, skb, user);
 179                 local_bh_enable();
 180                 if (err && err != -EINPROGRESS)
 181                         goto out_free;
 182         } else { /* NFPROTO_IPV6 */
 183 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
 184                 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
 185
 186                 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
 187                 err = nf_ct_frag6_gather(net, skb, user);
 188                 if (err && err != -EINPROGRESS)
 189                         goto out_free;
 190 #else
 191                 err = -EOPNOTSUPP;
 192                 goto out_free;
 193 #endif
 194         }
 195
 196         skb_clear_hash(skb);
 197         skb->ignore_df = 1;
 198         return err;
 199
 200 out_free:
 201         kfree_skb(skb);
 202         return err;
 203 }
 204
 205 static void tcf_ct_params_free(struct rcu_head *head)
 206 {
 207         struct tcf_ct_params *params = container_of(head,
 208                                                     struct tcf_ct_params, rcu);
 209
 210         if (params->tmpl)
 211                 nf_conntrack_put(&params->tmpl->ct_general);
 212         kfree(params);
 213 }
 214
 215 #if IS_ENABLED(CONFIG_NF_NAT)
 216 /* Modelled after nf_nat_ipv[46]_fn().
 217  * range is only used for new, uninitialized NAT state.
 218  * Returns either NF_ACCEPT or NF_DROP.
 219  */
 220 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
 221                           enum ip_conntrack_info ctinfo,
 222                           const struct nf_nat_range2 *range,
 223                           enum nf_nat_manip_type maniptype)
 224 {
 225         int hooknum, err = NF_ACCEPT;
 226
 227         /* See HOOK2MANIP(). */
 228         if (maniptype == NF_NAT_MANIP_SRC)
 229                 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
 230         else
 231                 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
 232
 233         switch (ctinfo) {
 234         case IP_CT_RELATED:
 235         case IP_CT_RELATED_REPLY:
 236                 if (skb->protocol == htons(ETH_P_IP) &&
 237                     ip_hdr(skb)->protocol == IPPROTO_ICMP) {
 238                         if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
 239                                                            hooknum))
 240                                 err = NF_DROP;
 241                         goto out;
 242                 } else if (IS_ENABLED(CONFIG_IPV6) &&
 243                            skb->protocol == htons(ETH_P_IPV6)) {
 244                         __be16 frag_off;
 245                         u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 246                         int hdrlen = ipv6_skip_exthdr(skb,
 247                                                       sizeof(struct ipv6hdr),
 248                                                       &nexthdr, &frag_off);
 249
 250                         if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
 251                                 if (!nf_nat_icmpv6_reply_translation(skb, ct,
 252                                                                      ctinfo,
 253                                                                      hooknum,
 254                                                                      hdrlen))
 255                                         err = NF_DROP;
 256                                 goto out;
 257                         }
 258                 }
 259                 /* Non-ICMP, fall thru to initialize if needed. */
 260                 /* fall through */
 261         case IP_CT_NEW:
 262                 /* Seen it before?  This can happen for loopback, retrans,
 263                  * or local packets.
 264                  */
 265                 if (!nf_nat_initialized(ct, maniptype)) {
 266                         /* Initialize according to the NAT action. */
 267                         err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
 268                                 /* Action is set up to establish a new
 269                                  * mapping.
 270                                  */
 271                                 ? nf_nat_setup_info(ct, range, maniptype)
 272                                 : nf_nat_alloc_null_binding(ct, hooknum);
 273                         if (err != NF_ACCEPT)
 274                                 goto out;
 275                 }
 276                 break;
 277
 278         case IP_CT_ESTABLISHED:
 279         case IP_CT_ESTABLISHED_REPLY:
 280                 break;
 281
 282         default:
 283                 err = NF_DROP;
 284                 goto out;
 285         }
 286
 287         err = nf_nat_packet(ct, ctinfo, hooknum, skb);
 288 out:
 289         return err;
 290 }
 291 #endif /* CONFIG_NF_NAT */
 292
 293 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
 294 {
 295 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 296         u32 new_mark;
 297
 298         if (!mask)
 299                 return;
 300
 301         new_mark = mark | (ct->mark & ~(mask));
 302         if (ct->mark != new_mark) {
 303                 ct->mark = new_mark;
 304                 if (nf_ct_is_confirmed(ct))
 305                         nf_conntrack_event_cache(IPCT_MARK, ct);
 306         }
 307 #endif
 308 }
 309
 310 static void tcf_ct_act_set_labels(struct nf_conn *ct,
 311                                   u32 *labels,
 312                                   u32 *labels_m)
 313 {
 314 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
 315         size_t labels_sz = FIELD_SIZEOF(struct tcf_ct_params, labels);
 316
 317         if (!memchr_inv(labels_m, 0, labels_sz))
 318                 return;
 319
 320         nf_connlabels_replace(ct, labels, labels_m, 4);
 321 #endif
 322 }
 323
 324 static int tcf_ct_act_nat(struct sk_buff *skb,
 325                           struct nf_conn *ct,
 326                           enum ip_conntrack_info ctinfo,
 327                           int ct_action,
 328                           struct nf_nat_range2 *range,
 329                           bool commit)
 330 {
 331 #if IS_ENABLED(CONFIG_NF_NAT)
 332         enum nf_nat_manip_type maniptype;
 333
 334         if (!(ct_action & TCA_CT_ACT_NAT))
 335                 return NF_ACCEPT;
 336
 337         /* Add NAT extension if not confirmed yet. */
 338         if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
 339                 return NF_DROP;   /* Can't NAT. */
 340
 341         if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) &&
 342             (ctinfo != IP_CT_RELATED || commit)) {
 343                 /* NAT an established or related connection like before. */
 344                 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
 345                         /* This is the REPLY direction for a connection
 346                          * for which NAT was applied in the forward
 347                          * direction.  Do the reverse NAT.
 348                          */
 349                         maniptype = ct->status & IPS_SRC_NAT
 350                                 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
 351                 else
 352                         maniptype = ct->status & IPS_SRC_NAT
 353                                 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
 354         } else if (ct_action & TCA_CT_ACT_NAT_SRC) {
 355                 maniptype = NF_NAT_MANIP_SRC;
 356         } else if (ct_action & TCA_CT_ACT_NAT_DST) {
 357                 maniptype = NF_NAT_MANIP_DST;
 358         } else {
 359                 return NF_ACCEPT;
 360         }
 361
 362         return ct_nat_execute(skb, ct, ctinfo, range, maniptype);
 363 #else
 364         return NF_ACCEPT;
 365 #endif
 366 }
 367
 368 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
 369                       struct tcf_result *res)
 370 {
 371         struct net *net = dev_net(skb->dev);
 372         bool cached, commit, clear, force;
 373         enum ip_conntrack_info ctinfo;
 374         struct tcf_ct *c = to_ct(a);
 375         struct nf_conn *tmpl = NULL;
 376         struct nf_hook_state state;
 377         int nh_ofs, err, retval;
 378         struct tcf_ct_params *p;
 379         struct nf_conn *ct;
 380         u8 family;
 381
 382         p = rcu_dereference_bh(c->params);
 383
 384         retval = READ_ONCE(c->tcf_action);
 385         commit = p->ct_action & TCA_CT_ACT_COMMIT;
 386         clear = p->ct_action & TCA_CT_ACT_CLEAR;
 387         force = p->ct_action & TCA_CT_ACT_FORCE;
 388         tmpl = p->tmpl;
 389
 390         if (clear) {
 391                 ct = nf_ct_get(skb, &ctinfo);
 392                 if (ct) {
 393                         nf_conntrack_put(&ct->ct_general);
 394                         nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
 395                 }
 396
 397                 goto out;
 398         }
 399
 400         family = tcf_ct_skb_nf_family(skb);
 401         if (family == NFPROTO_UNSPEC)
 402                 goto drop;
 403
 404         /* The conntrack module expects to be working at L3.
 405          * We also try to pull the IPv4/6 header to linear area
 406          */
 407         nh_ofs = skb_network_offset(skb);
 408         skb_pull_rcsum(skb, nh_ofs);
 409         err = tcf_ct_handle_fragments(net, skb, family, p->zone);
 410         if (err == -EINPROGRESS) {
 411                 retval = TC_ACT_STOLEN;
 412                 goto out;
 413         }
 414         if (err)
 415                 goto drop;
 416
 417         err = tcf_ct_skb_network_trim(skb, family);
 418         if (err)
 419                 goto drop;
 420
 421         /* If we are recirculating packets to match on ct fields and
 422          * committing with a separate ct action, then we don't need to
 423          * actually run the packet through conntrack twice unless it's for a
 424          * different zone.
 425          */
 426         cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);
 427         if (!cached) {
 428                 /* Associate skb with specified zone. */
 429                 if (tmpl) {
 430                         ct = nf_ct_get(skb, &ctinfo);
 431                         if (skb_nfct(skb))
 432                                 nf_conntrack_put(skb_nfct(skb));
 433                         nf_conntrack_get(&tmpl->ct_general);
 434                         nf_ct_set(skb, tmpl, IP_CT_NEW);
 435                 }
 436
 437                 state.hook = NF_INET_PRE_ROUTING;
 438                 state.net = net;
 439                 state.pf = family;
 440                 err = nf_conntrack_in(skb, &state);
 441                 if (err != NF_ACCEPT)
 442                         goto out_push;
 443         }
 444
 445         ct = nf_ct_get(skb, &ctinfo);
 446         if (!ct)
 447                 goto out_push;
 448         nf_ct_deliver_cached_events(ct);
 449
 450         err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
 451         if (err != NF_ACCEPT)
 452                 goto drop;
 453
 454         if (commit) {
 455                 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
 456                 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
 457
 458                 /* This will take care of sending queued events
 459                  * even if the connection is already confirmed.
 460                  */
 461                 nf_conntrack_confirm(skb);
 462         }
 463
 464 out_push:
 465         skb_push_rcsum(skb, nh_ofs);
 466
 467 out:
 468         tcf_action_update_bstats(&c->common, skb);
 469         return retval;
 470
 471 drop:
 472         tcf_action_inc_drop_qstats(&c->common);
 473         return TC_ACT_SHOT;
 474 }
 475
 476 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
 477         [TCA_CT_ACTION] = { .type = NLA_U16 },
 478         [TCA_CT_PARMS] = { .type = NLA_EXACT_LEN, .len = sizeof(struct tc_ct) },
 479         [TCA_CT_ZONE] = { .type = NLA_U16 },
 480         [TCA_CT_MARK] = { .type = NLA_U32 },
 481         [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
 482         [TCA_CT_LABELS] = { .type = NLA_BINARY,
 483                             .len = 128 / BITS_PER_BYTE },
 484         [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
 485                                  .len = 128 / BITS_PER_BYTE },
 486         [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
 487         [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
 488         [TCA_CT_NAT_IPV6_MIN] = { .type = NLA_EXACT_LEN,
 489                                   .len = sizeof(struct in6_addr) },
 490         [TCA_CT_NAT_IPV6_MAX] = { .type = NLA_EXACT_LEN,
 491                                    .len = sizeof(struct in6_addr) },
 492         [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
 493         [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
 494 };
 495
 496 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
 497                                   struct tc_ct *parm,
 498                                   struct nlattr **tb,
 499                                   struct netlink_ext_ack *extack)
 500 {
 501         struct nf_nat_range2 *range;
 502
 503         if (!(p->ct_action & TCA_CT_ACT_NAT))
 504                 return 0;
 505
 506         if (!IS_ENABLED(CONFIG_NF_NAT)) {
 507                 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
 508                 return -EOPNOTSUPP;
 509         }
 510
 511         if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
 512                 return 0;
 513
 514         if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
 515             (p->ct_action & TCA_CT_ACT_NAT_DST)) {
 516                 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
 517                 return -EOPNOTSUPP;
 518         }
 519
 520         range = &p->range;
 521         if (tb[TCA_CT_NAT_IPV4_MIN]) {
 522                 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
 523
 524                 p->ipv4_range = true;
 525                 range->flags |= NF_NAT_RANGE_MAP_IPS;
 526                 range->min_addr.ip =
 527                         nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
 528
 529                 range->max_addr.ip = max_attr ?
 530                                      nla_get_in_addr(max_attr) :
 531                                      range->min_addr.ip;
 532         } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
 533                 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
 534
 535                 p->ipv4_range = false;
 536                 range->flags |= NF_NAT_RANGE_MAP_IPS;
 537                 range->min_addr.in6 =
 538                         nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
 539
 540                 range->max_addr.in6 = max_attr ?
 541                                       nla_get_in6_addr(max_attr) :
 542                                       range->min_addr.in6;
 543         }
 544
 545         if (tb[TCA_CT_NAT_PORT_MIN]) {
 546                 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
 547                 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
 548
 549                 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
 550                                        nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
 551                                        range->min_proto.all;
 552         }
 553
 554         return 0;
 555 }
 556
 557 static void tcf_ct_set_key_val(struct nlattr **tb,
 558                                void *val, int val_type,
 559                                void *mask, int mask_type,
 560                                int len)
 561 {
 562         if (!tb[val_type])
 563                 return;
 564         nla_memcpy(val, tb[val_type], len);
 565
 566         if (!mask)
 567                 return;
 568
 569         if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
 570                 memset(mask, 0xff, len);
 571         else
 572                 nla_memcpy(mask, tb[mask_type], len);
 573 }
 574
 575 static int tcf_ct_fill_params(struct net *net,
 576                               struct tcf_ct_params *p,
 577                               struct tc_ct *parm,
 578                               struct nlattr **tb,
 579                               struct netlink_ext_ack *extack)
 580 {
 581         struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
 582         struct nf_conntrack_zone zone;
 583         struct nf_conn *tmpl;
 584         int err;
 585
 586         p->zone = NF_CT_DEFAULT_ZONE_ID;
 587
 588         tcf_ct_set_key_val(tb,
 589                            &p->ct_action, TCA_CT_ACTION,
 590                            NULL, TCA_CT_UNSPEC,
 591                            sizeof(p->ct_action));
 592
 593         if (p->ct_action & TCA_CT_ACT_CLEAR)
 594                 return 0;
 595
 596         err = tcf_ct_fill_params_nat(p, parm, tb, extack);
 597         if (err)
 598                 return err;
 599
 600         if (tb[TCA_CT_MARK]) {
 601                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
 602                         NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
 603                         return -EOPNOTSUPP;
 604                 }
 605                 tcf_ct_set_key_val(tb,
 606                                    &p->mark, TCA_CT_MARK,
 607                                    &p->mark_mask, TCA_CT_MARK_MASK,
 608                                    sizeof(p->mark));
 609         }
 610
 611         if (tb[TCA_CT_LABELS]) {
 612                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
 613                         NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
 614                         return -EOPNOTSUPP;
 615                 }
 616
 617                 if (!tn->labels) {
 618                         NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
 619                         return -EOPNOTSUPP;
 620                 }
 621                 tcf_ct_set_key_val(tb,
 622                                    p->labels, TCA_CT_LABELS,
 623                                    p->labels_mask, TCA_CT_LABELS_MASK,
 624                                    sizeof(p->labels));
 625         }
 626
 627         if (tb[TCA_CT_ZONE]) {
 628                 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
 629                         NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
 630                         return -EOPNOTSUPP;
 631                 }
 632
 633                 tcf_ct_set_key_val(tb,
 634                                    &p->zone, TCA_CT_ZONE,
 635                                    NULL, TCA_CT_UNSPEC,
 636                                    sizeof(p->zone));
 637         }
 638
 639         if (p->zone == NF_CT_DEFAULT_ZONE_ID)
 640                 return 0;
 641
 642         nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
 643         tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
 644         if (!tmpl) {
 645                 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
 646                 return -ENOMEM;
 647         }
 648         __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
 649         nf_conntrack_get(&tmpl->ct_general);
 650         p->tmpl = tmpl;
 651
 652         return 0;
 653 }
 654
 655 static int tcf_ct_init(struct net *net, struct nlattr *nla,
 656                        struct nlattr *est, struct tc_action **a,
 657                        int replace, int bind, bool rtnl_held,
 658                        struct tcf_proto *tp, u32 flags,
 659                        struct netlink_ext_ack *extack)
 660 {
 661         struct tc_action_net *tn = net_generic(net, ct_net_id);
 662         struct tcf_ct_params *params = NULL;
 663         struct nlattr *tb[TCA_CT_MAX + 1];
 664         struct tcf_chain *goto_ch = NULL;
 665         struct tc_ct *parm;
 666         struct tcf_ct *c;
 667         int err, res = 0;
 668         u32 index;
 669
 670         if (!nla) {
 671                 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
 672                 return -EINVAL;
 673         }
 674
 675         err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
 676         if (err < 0)
 677                 return err;
 678
 679         if (!tb[TCA_CT_PARMS]) {
 680                 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
 681                 return -EINVAL;
 682         }
 683         parm = nla_data(tb[TCA_CT_PARMS]);
 684         index = parm->index;
 685         err = tcf_idr_check_alloc(tn, &index, a, bind);
 686         if (err < 0)
 687                 return err;
 688
 689         if (!err) {
 690                 err = tcf_idr_create_from_flags(tn, index, est, a,
 691                                                 &act_ct_ops, bind, flags);
 692                 if (err) {
 693                         tcf_idr_cleanup(tn, index);
 694                         return err;
 695                 }
 696                 res = ACT_P_CREATED;
 697         } else {
 698                 if (bind)
 699                         return 0;
 700
 701                 if (!replace) {
 702                         tcf_idr_release(*a, bind);
 703                         return -EEXIST;
 704                 }
 705         }
 706         err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
 707         if (err < 0)
 708                 goto cleanup;
 709
 710         c = to_ct(*a);
 711
 712         params = kzalloc(sizeof(*params), GFP_KERNEL);
 713         if (unlikely(!params)) {
 714                 err = -ENOMEM;
 715                 goto cleanup;
 716         }
 717
 718         err = tcf_ct_fill_params(net, params, parm, tb, extack);
 719         if (err)
 720                 goto cleanup;
 721
 722         spin_lock_bh(&c->tcf_lock);
 723         goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
 724         params = rcu_replace_pointer(c->params, params,
 725                                      lockdep_is_held(&c->tcf_lock));
 726         spin_unlock_bh(&c->tcf_lock);
 727
 728         if (goto_ch)
 729                 tcf_chain_put_by_act(goto_ch);
 730         if (params)
 731                 kfree_rcu(params, rcu);
 732         if (res == ACT_P_CREATED)
 733                 tcf_idr_insert(tn, *a);
 734
 735         return res;
 736
 737 cleanup:
 738         if (goto_ch)
 739                 tcf_chain_put_by_act(goto_ch);
 740         kfree(params);
 741         tcf_idr_release(*a, bind);
 742         return err;
 743 }
 744
 745 static void tcf_ct_cleanup(struct tc_action *a)
 746 {
 747         struct tcf_ct_params *params;
 748         struct tcf_ct *c = to_ct(a);
 749
 750         params = rcu_dereference_protected(c->params, 1);
 751         if (params)
 752                 call_rcu(&params->rcu, tcf_ct_params_free);
 753 }
 754
 755 static int tcf_ct_dump_key_val(struct sk_buff *skb,
 756                                void *val, int val_type,
 757                                void *mask, int mask_type,
 758                                int len)
 759 {
 760         int err;
 761
 762         if (mask && !memchr_inv(mask, 0, len))
 763                 return 0;
 764
 765         err = nla_put(skb, val_type, len, val);
 766         if (err)
 767                 return err;
 768
 769         if (mask_type != TCA_CT_UNSPEC) {
 770                 err = nla_put(skb, mask_type, len, mask);
 771                 if (err)
 772                         return err;
 773         }
 774
 775         return 0;
 776 }
 777
 778 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
 779 {
 780         struct nf_nat_range2 *range = &p->range;
 781
 782         if (!(p->ct_action & TCA_CT_ACT_NAT))
 783                 return 0;
 784
 785         if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
 786                 return 0;
 787
 788         if (range->flags & NF_NAT_RANGE_MAP_IPS) {
 789                 if (p->ipv4_range) {
 790                         if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
 791                                             range->min_addr.ip))
 792                                 return -1;
 793                         if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
 794                                             range->max_addr.ip))
 795                                 return -1;
 796                 } else {
 797                         if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
 798                                              &range->min_addr.in6))
 799                                 return -1;
 800                         if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
 801                                              &range->max_addr.in6))
 802                                 return -1;
 803                 }
 804         }
 805
 806         if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
 807                 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
 808                                  range->min_proto.all))
 809                         return -1;
 810                 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
 811                                  range->max_proto.all))
 812                         return -1;
 813         }
 814
 815         return 0;
 816 }
 817
 818 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
 819                               int bind, int ref)
 820 {
 821         unsigned char *b = skb_tail_pointer(skb);
 822         struct tcf_ct *c = to_ct(a);
 823         struct tcf_ct_params *p;
 824
 825         struct tc_ct opt = {
 826                 .index   = c->tcf_index,
 827                 .refcnt  = refcount_read(&c->tcf_refcnt) - ref,
 828                 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
 829         };
 830         struct tcf_t t;
 831
 832         spin_lock_bh(&c->tcf_lock);
 833         p = rcu_dereference_protected(c->params,
 834                                       lockdep_is_held(&c->tcf_lock));
 835         opt.action = c->tcf_action;
 836
 837         if (tcf_ct_dump_key_val(skb,
 838                                 &p->ct_action, TCA_CT_ACTION,
 839                                 NULL, TCA_CT_UNSPEC,
 840                                 sizeof(p->ct_action)))
 841                 goto nla_put_failure;
 842
 843         if (p->ct_action & TCA_CT_ACT_CLEAR)
 844                 goto skip_dump;
 845
 846         if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
 847             tcf_ct_dump_key_val(skb,
 848                                 &p->mark, TCA_CT_MARK,
 849                                 &p->mark_mask, TCA_CT_MARK_MASK,
 850                                 sizeof(p->mark)))
 851                 goto nla_put_failure;
 852
 853         if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
 854             tcf_ct_dump_key_val(skb,
 855                                 p->labels, TCA_CT_LABELS,
 856                                 p->labels_mask, TCA_CT_LABELS_MASK,
 857                                 sizeof(p->labels)))
 858                 goto nla_put_failure;
 859
 860         if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
 861             tcf_ct_dump_key_val(skb,
 862                                 &p->zone, TCA_CT_ZONE,
 863                                 NULL, TCA_CT_UNSPEC,
 864                                 sizeof(p->zone)))
 865                 goto nla_put_failure;
 866
 867         if (tcf_ct_dump_nat(skb, p))
 868                 goto nla_put_failure;
 869
 870 skip_dump:
 871         if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
 872                 goto nla_put_failure;
 873
 874         tcf_tm_dump(&t, &c->tcf_tm);
 875         if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
 876                 goto nla_put_failure;
 877         spin_unlock_bh(&c->tcf_lock);
 878
 879         return skb->len;
 880 nla_put_failure:
 881         spin_unlock_bh(&c->tcf_lock);
 882         nlmsg_trim(skb, b);
 883         return -1;
 884 }
 885
 886 static int tcf_ct_walker(struct net *net, struct sk_buff *skb,
 887                          struct netlink_callback *cb, int type,
 888                          const struct tc_action_ops *ops,
 889                          struct netlink_ext_ack *extack)
 890 {
 891         struct tc_action_net *tn = net_generic(net, ct_net_id);
 892
 893         return tcf_generic_walker(tn, skb, cb, type, ops, extack);
 894 }
 895
 896 static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index)
 897 {
 898         struct tc_action_net *tn = net_generic(net, ct_net_id);
 899
 900         return tcf_idr_search(tn, a, index);
 901 }
 902
 903 static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets,
 904                              u64 lastuse, bool hw)
 905 {
 906         struct tcf_ct *c = to_ct(a);
 907
 908         tcf_action_update_stats(a, bytes, packets, false, hw);
 909         c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
 910 }
 911
 912 static struct tc_action_ops act_ct_ops = {
 913         .kind           =       "ct",
 914         .id             =       TCA_ID_CT,
 915         .owner          =       THIS_MODULE,
 916         .act            =       tcf_ct_act,
 917         .dump           =       tcf_ct_dump,
 918         .init           =       tcf_ct_init,
 919         .cleanup        =       tcf_ct_cleanup,
 920         .walk           =       tcf_ct_walker,
 921         .lookup         =       tcf_ct_search,
 922         .stats_update   =       tcf_stats_update,
 923         .size           =       sizeof(struct tcf_ct),
 924 };
 925
 926 static __net_init int ct_init_net(struct net *net)
 927 {
 928         unsigned int n_bits = FIELD_SIZEOF(struct tcf_ct_params, labels) * 8;
 929         struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
 930
 931         if (nf_connlabels_get(net, n_bits - 1)) {
 932                 tn->labels = false;
 933                 pr_err("act_ct: Failed to set connlabels length");
 934         } else {
 935                 tn->labels = true;
 936         }
 937
 938         return tc_action_net_init(net, &tn->tn, &act_ct_ops);
 939 }
 940
 941 static void __net_exit ct_exit_net(struct list_head *net_list)
 942 {
 943         struct net *net;
 944
 945         rtnl_lock();
 946         list_for_each_entry(net, net_list, exit_list) {
 947                 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
 948
 949                 if (tn->labels)
 950                         nf_connlabels_put(net);
 951         }
 952         rtnl_unlock();
 953
 954         tc_action_net_exit(net_list, ct_net_id);
 955 }
 956
 957 static struct pernet_operations ct_net_ops = {
 958         .init = ct_init_net,
 959         .exit_batch = ct_exit_net,
 960         .id   = &ct_net_id,
 961         .size = sizeof(struct tc_ct_action_net),
 962 };
 963
 964 static int __init ct_init_module(void)
 965 {
 966         return tcf_register_action(&act_ct_ops, &ct_net_ops);
 967 }
 968
 969 static void __exit ct_cleanup_module(void)
 970 {
 971         tcf_unregister_action(&act_ct_ops, &ct_net_ops);
 972 }
 973
 974 module_init(ct_init_module);
 975 module_exit(ct_cleanup_module);
 976 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
 977 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
 978 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
 979 MODULE_DESCRIPTION("Connection tracking action");
 980 MODULE_LICENSE("GPL v2");
 981