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 <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
  37static struct workqueue_struct *act_ct_wq;
  38static struct rhashtable zones_ht;
  39static DEFINE_MUTEX(zones_mutex);
  40
  41struct 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
  52static 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
  59static struct flow_action_entry *
  60tcf_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
  67static 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 */
  87static void
  88tcf_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
 104static void
 105tcf_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
 117static void
 118tcf_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
 132static void
 133tcf_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
 150static void
 151tcf_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
 168static 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
 195static 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
 235static 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
 264err_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
 273static struct nf_flowtable_type flowtable_ct = {
 274        .action         = tcf_ct_flow_table_fill_actions,
 275        .owner          = THIS_MODULE,
 276};
 277
 278static 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);
 305out_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
 312err_init:
 313        rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
 314err_insert:
 315        kfree(ct_ft);
 316err_alloc:
 317        mutex_unlock(&zones_mutex);
 318        return err;
 319}
 320
 321static 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
 333static 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
 344static 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
 371err_add:
 372        flow_offload_free(entry);
 373err_alloc:
 374        clear_bit(IPS_OFFLOAD_BIT, &ct->status);
 375}
 376
 377static 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
 405static bool
 406tcf_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
 451static bool
 452tcf_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
 493static 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
 548static int tcf_ct_flow_tables_init(void)
 549{
 550        return rhashtable_init(&zones_ht, &zones_params);
 551}
 552
 553static void tcf_ct_flow_tables_uninit(void)
 554{
 555        rhashtable_destroy(&zones_ht);
 556}
 557
 558static struct tc_action_ops act_ct_ops;
 559static unsigned int ct_net_id;
 560
 561struct 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. */
 567static 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 */
 601static 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
 623static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
 624{
 625        u8 family = NFPROTO_UNSPEC;
 626
 627        switch (skb_protocol(skb, true)) {
 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
 641static 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
 655static 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
 675static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
 676                                   u8 family, u16 zone, bool *defrag)
 677{
 678        enum ip_conntrack_info ctinfo;
 679        struct qdisc_skb_cb cb;
 680        struct nf_conn *ct;
 681        int err = 0;
 682        bool frag;
 683
 684        /* Previously seen (loopback)? Ignore. */
 685        ct = nf_ct_get(skb, &ctinfo);
 686        if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
 687                return 0;
 688
 689        if (family == NFPROTO_IPV4)
 690                err = tcf_ct_ipv4_is_fragment(skb, &frag);
 691        else
 692                err = tcf_ct_ipv6_is_fragment(skb, &frag);
 693        if (err || !frag)
 694                return err;
 695
 696        skb_get(skb);
 697        cb = *qdisc_skb_cb(skb);
 698
 699        if (family == NFPROTO_IPV4) {
 700                enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
 701
 702                memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
 703                local_bh_disable();
 704                err = ip_defrag(net, skb, user);
 705                local_bh_enable();
 706                if (err && err != -EINPROGRESS)
 707                        goto out_free;
 708
 709                if (!err)
 710                        *defrag = true;
 711        } else { /* NFPROTO_IPV6 */
 712#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
 713                enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
 714
 715                memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
 716                err = nf_ct_frag6_gather(net, skb, user);
 717                if (err && err != -EINPROGRESS)
 718                        goto out_free;
 719
 720                if (!err)
 721                        *defrag = true;
 722#else
 723                err = -EOPNOTSUPP;
 724                goto out_free;
 725#endif
 726        }
 727
 728        *qdisc_skb_cb(skb) = cb;
 729        skb_clear_hash(skb);
 730        skb->ignore_df = 1;
 731        return err;
 732
 733out_free:
 734        kfree_skb(skb);
 735        return err;
 736}
 737
 738static void tcf_ct_params_free(struct rcu_head *head)
 739{
 740        struct tcf_ct_params *params = container_of(head,
 741                                                    struct tcf_ct_params, rcu);
 742
 743        tcf_ct_flow_table_put(params);
 744
 745        if (params->tmpl)
 746                nf_conntrack_put(&params->tmpl->ct_general);
 747        kfree(params);
 748}
 749
 750#if IS_ENABLED(CONFIG_NF_NAT)
 751/* Modelled after nf_nat_ipv[46]_fn().
 752 * range is only used for new, uninitialized NAT state.
 753 * Returns either NF_ACCEPT or NF_DROP.
 754 */
 755static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
 756                          enum ip_conntrack_info ctinfo,
 757                          const struct nf_nat_range2 *range,
 758                          enum nf_nat_manip_type maniptype)
 759{
 760        __be16 proto = skb_protocol(skb, true);
 761        int hooknum, err = NF_ACCEPT;
 762
 763        /* See HOOK2MANIP(). */
 764        if (maniptype == NF_NAT_MANIP_SRC)
 765                hooknum = NF_INET_LOCAL_IN; /* Source NAT */
 766        else
 767                hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
 768
 769        switch (ctinfo) {
 770        case IP_CT_RELATED:
 771        case IP_CT_RELATED_REPLY:
 772                if (proto == htons(ETH_P_IP) &&
 773                    ip_hdr(skb)->protocol == IPPROTO_ICMP) {
 774                        if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
 775                                                           hooknum))
 776                                err = NF_DROP;
 777                        goto out;
 778                } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) {
 779                        __be16 frag_off;
 780                        u8 nexthdr = ipv6_hdr(skb)->nexthdr;
 781                        int hdrlen = ipv6_skip_exthdr(skb,
 782                                                      sizeof(struct ipv6hdr),
 783                                                      &nexthdr, &frag_off);
 784
 785                        if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
 786                                if (!nf_nat_icmpv6_reply_translation(skb, ct,
 787                                                                     ctinfo,
 788                                                                     hooknum,
 789                                                                     hdrlen))
 790                                        err = NF_DROP;
 791                                goto out;
 792                        }
 793                }
 794                /* Non-ICMP, fall thru to initialize if needed. */
 795                /* fall through */
 796        case IP_CT_NEW:
 797                /* Seen it before?  This can happen for loopback, retrans,
 798                 * or local packets.
 799                 */
 800                if (!nf_nat_initialized(ct, maniptype)) {
 801                        /* Initialize according to the NAT action. */
 802                        err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
 803                                /* Action is set up to establish a new
 804                                 * mapping.
 805                                 */
 806                                ? nf_nat_setup_info(ct, range, maniptype)
 807                                : nf_nat_alloc_null_binding(ct, hooknum);
 808                        if (err != NF_ACCEPT)
 809                                goto out;
 810                }
 811                break;
 812
 813        case IP_CT_ESTABLISHED:
 814        case IP_CT_ESTABLISHED_REPLY:
 815                break;
 816
 817        default:
 818                err = NF_DROP;
 819                goto out;
 820        }
 821
 822        err = nf_nat_packet(ct, ctinfo, hooknum, skb);
 823out:
 824        return err;
 825}
 826#endif /* CONFIG_NF_NAT */
 827
 828static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
 829{
 830#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
 831        u32 new_mark;
 832
 833        if (!mask)
 834                return;
 835
 836        new_mark = mark | (ct->mark & ~(mask));
 837        if (ct->mark != new_mark) {
 838                ct->mark = new_mark;
 839                if (nf_ct_is_confirmed(ct))
 840                        nf_conntrack_event_cache(IPCT_MARK, ct);
 841        }
 842#endif
 843}
 844
 845static void tcf_ct_act_set_labels(struct nf_conn *ct,
 846                                  u32 *labels,
 847                                  u32 *labels_m)
 848{
 849#if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
 850        size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
 851
 852        if (!memchr_inv(labels_m, 0, labels_sz))
 853                return;
 854
 855        nf_connlabels_replace(ct, labels, labels_m, 4);
 856#endif
 857}
 858
 859static int tcf_ct_act_nat(struct sk_buff *skb,
 860                          struct nf_conn *ct,
 861                          enum ip_conntrack_info ctinfo,
 862                          int ct_action,
 863                          struct nf_nat_range2 *range,
 864                          bool commit)
 865{
 866#if IS_ENABLED(CONFIG_NF_NAT)
 867        int err;
 868        enum nf_nat_manip_type maniptype;
 869
 870        if (!(ct_action & TCA_CT_ACT_NAT))
 871                return NF_ACCEPT;
 872
 873        /* Add NAT extension if not confirmed yet. */
 874        if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
 875                return NF_DROP;   /* Can't NAT. */
 876
 877        if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) &&
 878            (ctinfo != IP_CT_RELATED || commit)) {
 879                /* NAT an established or related connection like before. */
 880                if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
 881                        /* This is the REPLY direction for a connection
 882                         * for which NAT was applied in the forward
 883                         * direction.  Do the reverse NAT.
 884                         */
 885                        maniptype = ct->status & IPS_SRC_NAT
 886                                ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
 887                else
 888                        maniptype = ct->status & IPS_SRC_NAT
 889                                ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
 890        } else if (ct_action & TCA_CT_ACT_NAT_SRC) {
 891                maniptype = NF_NAT_MANIP_SRC;
 892        } else if (ct_action & TCA_CT_ACT_NAT_DST) {
 893                maniptype = NF_NAT_MANIP_DST;
 894        } else {
 895                return NF_ACCEPT;
 896        }
 897
 898        err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
 899        if (err == NF_ACCEPT &&
 900            ct->status & IPS_SRC_NAT && ct->status & IPS_DST_NAT) {
 901                if (maniptype == NF_NAT_MANIP_SRC)
 902                        maniptype = NF_NAT_MANIP_DST;
 903                else
 904                        maniptype = NF_NAT_MANIP_SRC;
 905
 906                err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
 907        }
 908        return err;
 909#else
 910        return NF_ACCEPT;
 911#endif
 912}
 913
 914static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
 915                      struct tcf_result *res)
 916{
 917        struct net *net = dev_net(skb->dev);
 918        bool cached, commit, clear, force;
 919        enum ip_conntrack_info ctinfo;
 920        struct tcf_ct *c = to_ct(a);
 921        struct nf_conn *tmpl = NULL;
 922        struct nf_hook_state state;
 923        int nh_ofs, err, retval;
 924        struct tcf_ct_params *p;
 925        bool skip_add = false;
 926        bool defrag = false;
 927        struct nf_conn *ct;
 928        u8 family;
 929
 930        p = rcu_dereference_bh(c->params);
 931
 932        retval = READ_ONCE(c->tcf_action);
 933        commit = p->ct_action & TCA_CT_ACT_COMMIT;
 934        clear = p->ct_action & TCA_CT_ACT_CLEAR;
 935        force = p->ct_action & TCA_CT_ACT_FORCE;
 936        tmpl = p->tmpl;
 937
 938        tcf_lastuse_update(&c->tcf_tm);
 939
 940        if (clear) {
 941                ct = nf_ct_get(skb, &ctinfo);
 942                if (ct) {
 943                        nf_conntrack_put(&ct->ct_general);
 944                        nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
 945                }
 946
 947                goto out;
 948        }
 949
 950        family = tcf_ct_skb_nf_family(skb);
 951        if (family == NFPROTO_UNSPEC)
 952                goto drop;
 953
 954        /* The conntrack module expects to be working at L3.
 955         * We also try to pull the IPv4/6 header to linear area
 956         */
 957        nh_ofs = skb_network_offset(skb);
 958        skb_pull_rcsum(skb, nh_ofs);
 959        err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
 960        if (err == -EINPROGRESS) {
 961                retval = TC_ACT_STOLEN;
 962                goto out;
 963        }
 964        if (err)
 965                goto drop;
 966
 967        err = tcf_ct_skb_network_trim(skb, family);
 968        if (err)
 969                goto drop;
 970
 971        /* If we are recirculating packets to match on ct fields and
 972         * committing with a separate ct action, then we don't need to
 973         * actually run the packet through conntrack twice unless it's for a
 974         * different zone.
 975         */
 976        cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);
 977        if (!cached) {
 978                if (!commit && tcf_ct_flow_table_lookup(p, skb, family)) {
 979                        skip_add = true;
 980                        goto do_nat;
 981                }
 982
 983                /* Associate skb with specified zone. */
 984                if (tmpl) {
 985                        ct = nf_ct_get(skb, &ctinfo);
 986                        if (skb_nfct(skb))
 987                                nf_conntrack_put(skb_nfct(skb));
 988                        nf_conntrack_get(&tmpl->ct_general);
 989                        nf_ct_set(skb, tmpl, IP_CT_NEW);
 990                }
 991
 992                state.hook = NF_INET_PRE_ROUTING;
 993                state.net = net;
 994                state.pf = family;
 995                err = nf_conntrack_in(skb, &state);
 996                if (err != NF_ACCEPT)
 997                        goto out_push;
 998        }
 999
1000do_nat:
1001        ct = nf_ct_get(skb, &ctinfo);
1002        if (!ct)
1003                goto out_push;
1004        nf_ct_deliver_cached_events(ct);
1005
1006        err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1007        if (err != NF_ACCEPT)
1008                goto drop;
1009
1010        if (commit) {
1011                tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1012                tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1013
1014                /* This will take care of sending queued events
1015                 * even if the connection is already confirmed.
1016                 */
1017                nf_conntrack_confirm(skb);
1018        } else if (!skip_add) {
1019                tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1020        }
1021
1022out_push:
1023        skb_push_rcsum(skb, nh_ofs);
1024
1025out:
1026        tcf_action_update_bstats(&c->common, skb);
1027        if (defrag)
1028                qdisc_skb_cb(skb)->pkt_len = skb->len;
1029        return retval;
1030
1031drop:
1032        tcf_action_inc_drop_qstats(&c->common);
1033        return TC_ACT_SHOT;
1034}
1035
1036static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1037        [TCA_CT_ACTION] = { .type = NLA_U16 },
1038        [TCA_CT_PARMS] = { .type = NLA_EXACT_LEN, .len = sizeof(struct tc_ct) },
1039        [TCA_CT_ZONE] = { .type = NLA_U16 },
1040        [TCA_CT_MARK] = { .type = NLA_U32 },
1041        [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1042        [TCA_CT_LABELS] = { .type = NLA_BINARY,
1043                            .len = 128 / BITS_PER_BYTE },
1044        [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1045                                 .len = 128 / BITS_PER_BYTE },
1046        [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1047        [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1048        [TCA_CT_NAT_IPV6_MIN] = { .type = NLA_EXACT_LEN,
1049                                  .len = sizeof(struct in6_addr) },
1050        [TCA_CT_NAT_IPV6_MAX] = { .type = NLA_EXACT_LEN,
1051                                   .len = sizeof(struct in6_addr) },
1052        [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1053        [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1054};
1055
1056static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1057                                  struct tc_ct *parm,
1058                                  struct nlattr **tb,
1059                                  struct netlink_ext_ack *extack)
1060{
1061        struct nf_nat_range2 *range;
1062
1063        if (!(p->ct_action & TCA_CT_ACT_NAT))
1064                return 0;
1065
1066        if (!IS_ENABLED(CONFIG_NF_NAT)) {
1067                NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1068                return -EOPNOTSUPP;
1069        }
1070
1071        if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1072                return 0;
1073
1074        if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1075            (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1076                NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1077                return -EOPNOTSUPP;
1078        }
1079
1080        range = &p->range;
1081        if (tb[TCA_CT_NAT_IPV4_MIN]) {
1082                struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1083
1084                p->ipv4_range = true;
1085                range->flags |= NF_NAT_RANGE_MAP_IPS;
1086                range->min_addr.ip =
1087                        nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1088
1089                range->max_addr.ip = max_attr ?
1090                                     nla_get_in_addr(max_attr) :
1091                                     range->min_addr.ip;
1092        } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1093                struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1094
1095                p->ipv4_range = false;
1096                range->flags |= NF_NAT_RANGE_MAP_IPS;
1097                range->min_addr.in6 =
1098                        nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1099
1100                range->max_addr.in6 = max_attr ?
1101                                      nla_get_in6_addr(max_attr) :
1102                                      range->min_addr.in6;
1103        }
1104
1105        if (tb[TCA_CT_NAT_PORT_MIN]) {
1106                range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1107                range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1108
1109                range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1110                                       nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1111                                       range->min_proto.all;
1112        }
1113
1114        return 0;
1115}
1116
1117static void tcf_ct_set_key_val(struct nlattr **tb,
1118                               void *val, int val_type,
1119                               void *mask, int mask_type,
1120                               int len)
1121{
1122        if (!tb[val_type])
1123                return;
1124        nla_memcpy(val, tb[val_type], len);
1125
1126        if (!mask)
1127                return;
1128
1129        if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1130                memset(mask, 0xff, len);
1131        else
1132                nla_memcpy(mask, tb[mask_type], len);
1133}
1134
1135static int tcf_ct_fill_params(struct net *net,
1136                              struct tcf_ct_params *p,
1137                              struct tc_ct *parm,
1138                              struct nlattr **tb,
1139                              struct netlink_ext_ack *extack)
1140{
1141        struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1142        struct nf_conntrack_zone zone;
1143        struct nf_conn *tmpl;
1144        int err;
1145
1146        p->zone = NF_CT_DEFAULT_ZONE_ID;
1147
1148        tcf_ct_set_key_val(tb,
1149                           &p->ct_action, TCA_CT_ACTION,
1150                           NULL, TCA_CT_UNSPEC,
1151                           sizeof(p->ct_action));
1152
1153        if (p->ct_action & TCA_CT_ACT_CLEAR)
1154                return 0;
1155
1156        err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1157        if (err)
1158                return err;
1159
1160        if (tb[TCA_CT_MARK]) {
1161                if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1162                        NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1163                        return -EOPNOTSUPP;
1164                }
1165                tcf_ct_set_key_val(tb,
1166                                   &p->mark, TCA_CT_MARK,
1167                                   &p->mark_mask, TCA_CT_MARK_MASK,
1168                                   sizeof(p->mark));
1169        }
1170
1171        if (tb[TCA_CT_LABELS]) {
1172                if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1173                        NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1174                        return -EOPNOTSUPP;
1175                }
1176
1177                if (!tn->labels) {
1178                        NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1179                        return -EOPNOTSUPP;
1180                }
1181                tcf_ct_set_key_val(tb,
1182                                   p->labels, TCA_CT_LABELS,
1183                                   p->labels_mask, TCA_CT_LABELS_MASK,
1184                                   sizeof(p->labels));
1185        }
1186
1187        if (tb[TCA_CT_ZONE]) {
1188                if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1189                        NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1190                        return -EOPNOTSUPP;
1191                }
1192
1193                tcf_ct_set_key_val(tb,
1194                                   &p->zone, TCA_CT_ZONE,
1195                                   NULL, TCA_CT_UNSPEC,
1196                                   sizeof(p->zone));
1197        }
1198
1199        if (p->zone == NF_CT_DEFAULT_ZONE_ID)
1200                return 0;
1201
1202        nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1203        tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1204        if (!tmpl) {
1205                NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1206                return -ENOMEM;
1207        }
1208        __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1209        nf_conntrack_get(&tmpl->ct_general);
1210        p->tmpl = tmpl;
1211
1212        return 0;
1213}
1214
1215static int tcf_ct_init(struct net *net, struct nlattr *nla,
1216                       struct nlattr *est, struct tc_action **a,
1217                       int replace, int bind, bool rtnl_held,
1218                       struct tcf_proto *tp, u32 flags,
1219                       struct netlink_ext_ack *extack)
1220{
1221        struct tc_action_net *tn = net_generic(net, ct_net_id);
1222        struct tcf_ct_params *params = NULL;
1223        struct nlattr *tb[TCA_CT_MAX + 1];
1224        struct tcf_chain *goto_ch = NULL;
1225        struct tc_ct *parm;
1226        struct tcf_ct *c;
1227        int err, res = 0;
1228        u32 index;
1229
1230        if (!nla) {
1231                NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1232                return -EINVAL;
1233        }
1234
1235        err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1236        if (err < 0)
1237                return err;
1238
1239        if (!tb[TCA_CT_PARMS]) {
1240                NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1241                return -EINVAL;
1242        }
1243        parm = nla_data(tb[TCA_CT_PARMS]);
1244        index = parm->index;
1245        err = tcf_idr_check_alloc(tn, &index, a, bind);
1246        if (err < 0)
1247                return err;
1248
1249        if (!err) {
1250                err = tcf_idr_create_from_flags(tn, index, est, a,
1251                                                &act_ct_ops, bind, flags);
1252                if (err) {
1253                        tcf_idr_cleanup(tn, index);
1254                        return err;
1255                }
1256                res = ACT_P_CREATED;
1257        } else {
1258                if (bind)
1259                        return 0;
1260
1261                if (!replace) {
1262                        tcf_idr_release(*a, bind);
1263                        return -EEXIST;
1264                }
1265        }
1266        err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1267        if (err < 0)
1268                goto cleanup;
1269
1270        c = to_ct(*a);
1271
1272        params = kzalloc(sizeof(*params), GFP_KERNEL);
1273        if (unlikely(!params)) {
1274                err = -ENOMEM;
1275                goto cleanup;
1276        }
1277
1278        err = tcf_ct_fill_params(net, params, parm, tb, extack);
1279        if (err)
1280                goto cleanup;
1281
1282        err = tcf_ct_flow_table_get(params);
1283        if (err)
1284                goto cleanup;
1285
1286        spin_lock_bh(&c->tcf_lock);
1287        goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1288        params = rcu_replace_pointer(c->params, params,
1289                                     lockdep_is_held(&c->tcf_lock));
1290        spin_unlock_bh(&c->tcf_lock);
1291
1292        if (goto_ch)
1293                tcf_chain_put_by_act(goto_ch);
1294        if (params)
1295                call_rcu(&params->rcu, tcf_ct_params_free);
1296        if (res == ACT_P_CREATED)
1297                tcf_idr_insert(tn, *a);
1298
1299        return res;
1300
1301cleanup:
1302        if (goto_ch)
1303                tcf_chain_put_by_act(goto_ch);
1304        kfree(params);
1305        tcf_idr_release(*a, bind);
1306        return err;
1307}
1308
1309static void tcf_ct_cleanup(struct tc_action *a)
1310{
1311        struct tcf_ct_params *params;
1312        struct tcf_ct *c = to_ct(a);
1313
1314        params = rcu_dereference_protected(c->params, 1);
1315        if (params)
1316                call_rcu(&params->rcu, tcf_ct_params_free);
1317}
1318
1319static int tcf_ct_dump_key_val(struct sk_buff *skb,
1320                               void *val, int val_type,
1321                               void *mask, int mask_type,
1322                               int len)
1323{
1324        int err;
1325
1326        if (mask && !memchr_inv(mask, 0, len))
1327                return 0;
1328
1329        err = nla_put(skb, val_type, len, val);
1330        if (err)
1331                return err;
1332
1333        if (mask_type != TCA_CT_UNSPEC) {
1334                err = nla_put(skb, mask_type, len, mask);
1335                if (err)
1336                        return err;
1337        }
1338
1339        return 0;
1340}
1341
1342static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1343{
1344        struct nf_nat_range2 *range = &p->range;
1345
1346        if (!(p->ct_action & TCA_CT_ACT_NAT))
1347                return 0;
1348
1349        if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1350                return 0;
1351
1352        if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1353                if (p->ipv4_range) {
1354                        if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1355                                            range->min_addr.ip))
1356                                return -1;
1357                        if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1358                                            range->max_addr.ip))
1359                                return -1;
1360                } else {
1361                        if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1362                                             &range->min_addr.in6))
1363                                return -1;
1364                        if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1365                                             &range->max_addr.in6))
1366                                return -1;
1367                }
1368        }
1369
1370        if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1371                if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1372                                 range->min_proto.all))
1373                        return -1;
1374                if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1375                                 range->max_proto.all))
1376                        return -1;
1377        }
1378
1379        return 0;
1380}
1381
1382static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1383                              int bind, int ref)
1384{
1385        unsigned char *b = skb_tail_pointer(skb);
1386        struct tcf_ct *c = to_ct(a);
1387        struct tcf_ct_params *p;
1388
1389        struct tc_ct opt = {
1390                .index   = c->tcf_index,
1391                .refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1392                .bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1393        };
1394        struct tcf_t t;
1395
1396        spin_lock_bh(&c->tcf_lock);
1397        p = rcu_dereference_protected(c->params,
1398                                      lockdep_is_held(&c->tcf_lock));
1399        opt.action = c->tcf_action;
1400
1401        if (tcf_ct_dump_key_val(skb,
1402                                &p->ct_action, TCA_CT_ACTION,
1403                                NULL, TCA_CT_UNSPEC,
1404                                sizeof(p->ct_action)))
1405                goto nla_put_failure;
1406
1407        if (p->ct_action & TCA_CT_ACT_CLEAR)
1408                goto skip_dump;
1409
1410        if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1411            tcf_ct_dump_key_val(skb,
1412                                &p->mark, TCA_CT_MARK,
1413                                &p->mark_mask, TCA_CT_MARK_MASK,
1414                                sizeof(p->mark)))
1415                goto nla_put_failure;
1416
1417        if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1418            tcf_ct_dump_key_val(skb,
1419                                p->labels, TCA_CT_LABELS,
1420                                p->labels_mask, TCA_CT_LABELS_MASK,
1421                                sizeof(p->labels)))
1422                goto nla_put_failure;
1423
1424        if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1425            tcf_ct_dump_key_val(skb,
1426                                &p->zone, TCA_CT_ZONE,
1427                                NULL, TCA_CT_UNSPEC,
1428                                sizeof(p->zone)))
1429                goto nla_put_failure;
1430
1431        if (tcf_ct_dump_nat(skb, p))
1432                goto nla_put_failure;
1433
1434skip_dump:
1435        if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1436                goto nla_put_failure;
1437
1438        tcf_tm_dump(&t, &c->tcf_tm);
1439        if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1440                goto nla_put_failure;
1441        spin_unlock_bh(&c->tcf_lock);
1442
1443        return skb->len;
1444nla_put_failure:
1445        spin_unlock_bh(&c->tcf_lock);
1446        nlmsg_trim(skb, b);
1447        return -1;
1448}
1449
1450static int tcf_ct_walker(struct net *net, struct sk_buff *skb,
1451                         struct netlink_callback *cb, int type,
1452                         const struct tc_action_ops *ops,
1453                         struct netlink_ext_ack *extack)
1454{
1455        struct tc_action_net *tn = net_generic(net, ct_net_id);
1456
1457        return tcf_generic_walker(tn, skb, cb, type, ops, extack);
1458}
1459
1460static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index)
1461{
1462        struct tc_action_net *tn = net_generic(net, ct_net_id);
1463
1464        return tcf_idr_search(tn, a, index);
1465}
1466
1467static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets,
1468                             u64 lastuse, bool hw)
1469{
1470        struct tcf_ct *c = to_ct(a);
1471
1472        tcf_action_update_stats(a, bytes, packets, false, hw);
1473        c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1474}
1475
1476static struct tc_action_ops act_ct_ops = {
1477        .kind           =       "ct",
1478        .id             =       TCA_ID_CT,
1479        .owner          =       THIS_MODULE,
1480        .act            =       tcf_ct_act,
1481        .dump           =       tcf_ct_dump,
1482        .init           =       tcf_ct_init,
1483        .cleanup        =       tcf_ct_cleanup,
1484        .walk           =       tcf_ct_walker,
1485        .lookup         =       tcf_ct_search,
1486        .stats_update   =       tcf_stats_update,
1487        .size           =       sizeof(struct tcf_ct),
1488};
1489
1490static __net_init int ct_init_net(struct net *net)
1491{
1492        unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1493        struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1494
1495        if (nf_connlabels_get(net, n_bits - 1)) {
1496                tn->labels = false;
1497                pr_err("act_ct: Failed to set connlabels length");
1498        } else {
1499                tn->labels = true;
1500        }
1501
1502        return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1503}
1504
1505static void __net_exit ct_exit_net(struct list_head *net_list)
1506{
1507        struct net *net;
1508
1509        rtnl_lock();
1510        list_for_each_entry(net, net_list, exit_list) {
1511                struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1512
1513                if (tn->labels)
1514                        nf_connlabels_put(net);
1515        }
1516        rtnl_unlock();
1517
1518        tc_action_net_exit(net_list, ct_net_id);
1519}
1520
1521static struct pernet_operations ct_net_ops = {
1522        .init = ct_init_net,
1523        .exit_batch = ct_exit_net,
1524        .id   = &ct_net_id,
1525        .size = sizeof(struct tc_ct_action_net),
1526};
1527
1528static int __init ct_init_module(void)
1529{
1530        int err;
1531
1532        act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1533        if (!act_ct_wq)
1534                return -ENOMEM;
1535
1536        err = tcf_ct_flow_tables_init();
1537        if (err)
1538                goto err_tbl_init;
1539
1540        err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1541        if (err)
1542                goto err_register;
1543
1544        return 0;
1545
1546err_register:
1547        tcf_ct_flow_tables_uninit();
1548err_tbl_init:
1549        destroy_workqueue(act_ct_wq);
1550        return err;
1551}
1552
1553static void __exit ct_cleanup_module(void)
1554{
1555        tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1556        tcf_ct_flow_tables_uninit();
1557        destroy_workqueue(act_ct_wq);
1558}
1559
1560module_init(ct_init_module);
1561module_exit(ct_cleanup_module);
1562MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1563MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1564MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1565MODULE_DESCRIPTION("Connection tracking action");
1566MODULE_LICENSE("GPL v2");
1567