linux/net/sched/act_ct.c
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   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 <linux/netfilter/nf_nat.h>
  28#include <net/netfilter/nf_conntrack.h>
  29#include <net/netfilter/nf_conntrack_core.h>
  30#include <net/netfilter/nf_conntrack_zones.h>
  31#include <net/netfilter/nf_conntrack_helper.h>
  32#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
  33
  34static struct tc_action_ops act_ct_ops;
  35static unsigned int ct_net_id;
  36
  37struct 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. */
  43static 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 */
  77static 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
  99static 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
 117static 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
 131static 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
 151static 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
 200out_free:
 201        kfree_skb(skb);
 202        return err;
 203}
 204
 205static 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 */
 220static 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);
 288out:
 289        return err;
 290}
 291#endif /* CONFIG_NF_NAT */
 292
 293static 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
 310static 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
 324static 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
 368static 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
 464out_push:
 465        skb_push_rcsum(skb, nh_ofs);
 466
 467out:
 468        bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), skb);
 469        return retval;
 470
 471drop:
 472        qstats_drop_inc(this_cpu_ptr(a->cpu_qstats));
 473        return TC_ACT_SHOT;
 474}
 475
 476static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
 477        [TCA_CT_UNSPEC] = { .strict_start_type = TCA_CT_UNSPEC + 1 },
 478        [TCA_CT_ACTION] = { .type = NLA_U16 },
 479        [TCA_CT_PARMS] = { .type = NLA_EXACT_LEN, .len = sizeof(struct tc_ct) },
 480        [TCA_CT_ZONE] = { .type = NLA_U16 },
 481        [TCA_CT_MARK] = { .type = NLA_U32 },
 482        [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
 483        [TCA_CT_LABELS] = { .type = NLA_BINARY,
 484                            .len = 128 / BITS_PER_BYTE },
 485        [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
 486                                 .len = 128 / BITS_PER_BYTE },
 487        [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
 488        [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
 489        [TCA_CT_NAT_IPV6_MIN] = { .type = NLA_EXACT_LEN,
 490                                  .len = sizeof(struct in6_addr) },
 491        [TCA_CT_NAT_IPV6_MAX] = { .type = NLA_EXACT_LEN,
 492                                   .len = sizeof(struct in6_addr) },
 493        [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
 494        [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
 495};
 496
 497static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
 498                                  struct tc_ct *parm,
 499                                  struct nlattr **tb,
 500                                  struct netlink_ext_ack *extack)
 501{
 502        struct nf_nat_range2 *range;
 503
 504        if (!(p->ct_action & TCA_CT_ACT_NAT))
 505                return 0;
 506
 507        if (!IS_ENABLED(CONFIG_NF_NAT)) {
 508                NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
 509                return -EOPNOTSUPP;
 510        }
 511
 512        if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
 513                return 0;
 514
 515        if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
 516            (p->ct_action & TCA_CT_ACT_NAT_DST)) {
 517                NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
 518                return -EOPNOTSUPP;
 519        }
 520
 521        range = &p->range;
 522        if (tb[TCA_CT_NAT_IPV4_MIN]) {
 523                struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
 524
 525                p->ipv4_range = true;
 526                range->flags |= NF_NAT_RANGE_MAP_IPS;
 527                range->min_addr.ip =
 528                        nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
 529
 530                range->max_addr.ip = max_attr ?
 531                                     nla_get_in_addr(max_attr) :
 532                                     range->min_addr.ip;
 533        } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
 534                struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
 535
 536                p->ipv4_range = false;
 537                range->flags |= NF_NAT_RANGE_MAP_IPS;
 538                range->min_addr.in6 =
 539                        nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
 540
 541                range->max_addr.in6 = max_attr ?
 542                                      nla_get_in6_addr(max_attr) :
 543                                      range->min_addr.in6;
 544        }
 545
 546        if (tb[TCA_CT_NAT_PORT_MIN]) {
 547                range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
 548                range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
 549
 550                range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
 551                                       nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
 552                                       range->min_proto.all;
 553        }
 554
 555        return 0;
 556}
 557
 558static void tcf_ct_set_key_val(struct nlattr **tb,
 559                               void *val, int val_type,
 560                               void *mask, int mask_type,
 561                               int len)
 562{
 563        if (!tb[val_type])
 564                return;
 565        nla_memcpy(val, tb[val_type], len);
 566
 567        if (!mask)
 568                return;
 569
 570        if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
 571                memset(mask, 0xff, len);
 572        else
 573                nla_memcpy(mask, tb[mask_type], len);
 574}
 575
 576static int tcf_ct_fill_params(struct net *net,
 577                              struct tcf_ct_params *p,
 578                              struct tc_ct *parm,
 579                              struct nlattr **tb,
 580                              struct netlink_ext_ack *extack)
 581{
 582        struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
 583        struct nf_conntrack_zone zone;
 584        struct nf_conn *tmpl;
 585        int err;
 586
 587        p->zone = NF_CT_DEFAULT_ZONE_ID;
 588
 589        tcf_ct_set_key_val(tb,
 590                           &p->ct_action, TCA_CT_ACTION,
 591                           NULL, TCA_CT_UNSPEC,
 592                           sizeof(p->ct_action));
 593
 594        if (p->ct_action & TCA_CT_ACT_CLEAR)
 595                return 0;
 596
 597        err = tcf_ct_fill_params_nat(p, parm, tb, extack);
 598        if (err)
 599                return err;
 600
 601        if (tb[TCA_CT_MARK]) {
 602                if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
 603                        NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
 604                        return -EOPNOTSUPP;
 605                }
 606                tcf_ct_set_key_val(tb,
 607                                   &p->mark, TCA_CT_MARK,
 608                                   &p->mark_mask, TCA_CT_MARK_MASK,
 609                                   sizeof(p->mark));
 610        }
 611
 612        if (tb[TCA_CT_LABELS]) {
 613                if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
 614                        NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
 615                        return -EOPNOTSUPP;
 616                }
 617
 618                if (!tn->labels) {
 619                        NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
 620                        return -EOPNOTSUPP;
 621                }
 622                tcf_ct_set_key_val(tb,
 623                                   p->labels, TCA_CT_LABELS,
 624                                   p->labels_mask, TCA_CT_LABELS_MASK,
 625                                   sizeof(p->labels));
 626        }
 627
 628        if (tb[TCA_CT_ZONE]) {
 629                if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
 630                        NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
 631                        return -EOPNOTSUPP;
 632                }
 633
 634                tcf_ct_set_key_val(tb,
 635                                   &p->zone, TCA_CT_ZONE,
 636                                   NULL, TCA_CT_UNSPEC,
 637                                   sizeof(p->zone));
 638        }
 639
 640        if (p->zone == NF_CT_DEFAULT_ZONE_ID)
 641                return 0;
 642
 643        nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
 644        tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
 645        if (!tmpl) {
 646                NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
 647                return -ENOMEM;
 648        }
 649        __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
 650        nf_conntrack_get(&tmpl->ct_general);
 651        p->tmpl = tmpl;
 652
 653        return 0;
 654}
 655
 656static int tcf_ct_init(struct net *net, struct nlattr *nla,
 657                       struct nlattr *est, struct tc_action **a,
 658                       int replace, int bind, bool rtnl_held,
 659                       struct tcf_proto *tp,
 660                       struct netlink_ext_ack *extack)
 661{
 662        struct tc_action_net *tn = net_generic(net, ct_net_id);
 663        struct tcf_ct_params *params = NULL;
 664        struct nlattr *tb[TCA_CT_MAX + 1];
 665        struct tcf_chain *goto_ch = NULL;
 666        struct tc_ct *parm;
 667        struct tcf_ct *c;
 668        int err, res = 0;
 669        u32 index;
 670
 671        if (!nla) {
 672                NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
 673                return -EINVAL;
 674        }
 675
 676        err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
 677        if (err < 0)
 678                return err;
 679
 680        if (!tb[TCA_CT_PARMS]) {
 681                NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
 682                return -EINVAL;
 683        }
 684        parm = nla_data(tb[TCA_CT_PARMS]);
 685        index = parm->index;
 686        err = tcf_idr_check_alloc(tn, &index, a, bind);
 687        if (err < 0)
 688                return err;
 689
 690        if (!err) {
 691                err = tcf_idr_create(tn, index, est, a,
 692                                     &act_ct_ops, bind, true);
 693                if (err) {
 694                        tcf_idr_cleanup(tn, index);
 695                        return err;
 696                }
 697                res = ACT_P_CREATED;
 698        } else {
 699                if (bind)
 700                        return 0;
 701
 702                if (!replace) {
 703                        tcf_idr_release(*a, bind);
 704                        return -EEXIST;
 705                }
 706        }
 707        err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
 708        if (err < 0)
 709                goto cleanup;
 710
 711        c = to_ct(*a);
 712
 713        params = kzalloc(sizeof(*params), GFP_KERNEL);
 714        if (unlikely(!params)) {
 715                err = -ENOMEM;
 716                goto cleanup;
 717        }
 718
 719        err = tcf_ct_fill_params(net, params, parm, tb, extack);
 720        if (err)
 721                goto cleanup;
 722
 723        spin_lock_bh(&c->tcf_lock);
 724        goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
 725        rcu_swap_protected(c->params, params, 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
 737cleanup:
 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
 745static 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
 755static 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
 778static 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
 818static 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
 870skip_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;
 880nla_put_failure:
 881        spin_unlock_bh(&c->tcf_lock);
 882        nlmsg_trim(skb, b);
 883        return -1;
 884}
 885
 886static 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
 896static 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
 903static 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        _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
 909
 910        if (hw)
 911                _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats_hw),
 912                                   bytes, packets);
 913        c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
 914}
 915
 916static struct tc_action_ops act_ct_ops = {
 917        .kind           =       "ct",
 918        .id             =       TCA_ID_CT,
 919        .owner          =       THIS_MODULE,
 920        .act            =       tcf_ct_act,
 921        .dump           =       tcf_ct_dump,
 922        .init           =       tcf_ct_init,
 923        .cleanup        =       tcf_ct_cleanup,
 924        .walk           =       tcf_ct_walker,
 925        .lookup         =       tcf_ct_search,
 926        .stats_update   =       tcf_stats_update,
 927        .size           =       sizeof(struct tcf_ct),
 928};
 929
 930static __net_init int ct_init_net(struct net *net)
 931{
 932        unsigned int n_bits = FIELD_SIZEOF(struct tcf_ct_params, labels) * 8;
 933        struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
 934
 935        if (nf_connlabels_get(net, n_bits - 1)) {
 936                tn->labels = false;
 937                pr_err("act_ct: Failed to set connlabels length");
 938        } else {
 939                tn->labels = true;
 940        }
 941
 942        return tc_action_net_init(net, &tn->tn, &act_ct_ops);
 943}
 944
 945static void __net_exit ct_exit_net(struct list_head *net_list)
 946{
 947        struct net *net;
 948
 949        rtnl_lock();
 950        list_for_each_entry(net, net_list, exit_list) {
 951                struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
 952
 953                if (tn->labels)
 954                        nf_connlabels_put(net);
 955        }
 956        rtnl_unlock();
 957
 958        tc_action_net_exit(net_list, ct_net_id);
 959}
 960
 961static struct pernet_operations ct_net_ops = {
 962        .init = ct_init_net,
 963        .exit_batch = ct_exit_net,
 964        .id   = &ct_net_id,
 965        .size = sizeof(struct tc_ct_action_net),
 966};
 967
 968static int __init ct_init_module(void)
 969{
 970        return tcf_register_action(&act_ct_ops, &ct_net_ops);
 971}
 972
 973static void __exit ct_cleanup_module(void)
 974{
 975        tcf_unregister_action(&act_ct_ops, &ct_net_ops);
 976}
 977
 978module_init(ct_init_module);
 979module_exit(ct_cleanup_module);
 980MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
 981MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
 982MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
 983MODULE_DESCRIPTION("Connection tracking action");
 984MODULE_LICENSE("GPL v2");
 985
 986