1 // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB 2 /* - 3 * net/sched/act_ct.c Connection Tracking action 4 * 5 * Authors: Paul Blakey <paulb@mellanox.com> 6 * Yossi Kuperman <yossiku@mellanox.com> 7 * Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> 8 */ 9 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/kernel.h> 13 #include <linux/skbuff.h> 14 #include <linux/rtnetlink.h> 15 #include <linux/pkt_cls.h> 16 #include <linux/ip.h> 17 #include <linux/ipv6.h> 18 #include <linux/rhashtable.h> 19 #include <net/netlink.h> 20 #include <net/pkt_sched.h> 21 #include <net/pkt_cls.h> 22 #include <net/act_api.h> 23 #include <net/ip.h> 24 #include <net/ipv6_frag.h> 25 #include <uapi/linux/tc_act/tc_ct.h> 26 #include <net/tc_act/tc_ct.h> 27 28 #include <net/netfilter/nf_flow_table.h> 29 #include <net/netfilter/nf_conntrack.h> 30 #include <net/netfilter/nf_conntrack_core.h> 31 #include <net/netfilter/nf_conntrack_zones.h> 32 #include <net/netfilter/nf_conntrack_helper.h> 33 #include <net/netfilter/nf_conntrack_acct.h> 34 #include <net/netfilter/ipv6/nf_defrag_ipv6.h> 35 #include <uapi/linux/netfilter/nf_nat.h> 36 37 static struct workqueue_struct *act_ct_wq; 38 static struct rhashtable zones_ht; 39 static DEFINE_MUTEX(zones_mutex); 40 41 struct tcf_ct_flow_table { 42 struct rhash_head node; /* In zones tables */ 43 44 struct rcu_work rwork; 45 struct nf_flowtable nf_ft; 46 refcount_t ref; 47 u16 zone; 48 49 bool dying; 50 }; 51 52 static const struct rhashtable_params zones_params = { 53 .head_offset = offsetof(struct tcf_ct_flow_table, node), 54 .key_offset = offsetof(struct tcf_ct_flow_table, zone), 55 .key_len = sizeof_field(struct tcf_ct_flow_table, zone), 56 .automatic_shrinking = true, 57 }; 58 59 static struct flow_action_entry * 60 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action) 61 { 62 int i = flow_action->num_entries++; 63 64 return &flow_action->entries[i]; 65 } 66 67 static void tcf_ct_add_mangle_action(struct flow_action *action, 68 enum flow_action_mangle_base htype, 69 u32 offset, 70 u32 mask, 71 u32 val) 72 { 73 struct flow_action_entry *entry; 74 75 entry = tcf_ct_flow_table_flow_action_get_next(action); 76 entry->id = FLOW_ACTION_MANGLE; 77 entry->mangle.htype = htype; 78 entry->mangle.mask = ~mask; 79 entry->mangle.offset = offset; 80 entry->mangle.val = val; 81 } 82 83 /* The following nat helper functions check if the inverted reverse tuple 84 * (target) is different then the current dir tuple - meaning nat for ports 85 * and/or ip is needed, and add the relevant mangle actions. 86 */ 87 static void 88 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple, 89 struct nf_conntrack_tuple target, 90 struct flow_action *action) 91 { 92 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) 93 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, 94 offsetof(struct iphdr, saddr), 95 0xFFFFFFFF, 96 be32_to_cpu(target.src.u3.ip)); 97 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) 98 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, 99 offsetof(struct iphdr, daddr), 100 0xFFFFFFFF, 101 be32_to_cpu(target.dst.u3.ip)); 102 } 103 104 static void 105 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action, 106 union nf_inet_addr *addr, 107 u32 offset) 108 { 109 int i; 110 111 for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++) 112 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6, 113 i * sizeof(u32) + offset, 114 0xFFFFFFFF, be32_to_cpu(addr->ip6[i])); 115 } 116 117 static void 118 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple, 119 struct nf_conntrack_tuple target, 120 struct flow_action *action) 121 { 122 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) 123 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3, 124 offsetof(struct ipv6hdr, 125 saddr)); 126 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) 127 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3, 128 offsetof(struct ipv6hdr, 129 daddr)); 130 } 131 132 static void 133 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple, 134 struct nf_conntrack_tuple target, 135 struct flow_action *action) 136 { 137 __be16 target_src = target.src.u.tcp.port; 138 __be16 target_dst = target.dst.u.tcp.port; 139 140 if (target_src != tuple->src.u.tcp.port) 141 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, 142 offsetof(struct tcphdr, source), 143 0xFFFF, be16_to_cpu(target_src)); 144 if (target_dst != tuple->dst.u.tcp.port) 145 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, 146 offsetof(struct tcphdr, dest), 147 0xFFFF, be16_to_cpu(target_dst)); 148 } 149 150 static void 151 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple, 152 struct nf_conntrack_tuple target, 153 struct flow_action *action) 154 { 155 __be16 target_src = target.src.u.udp.port; 156 __be16 target_dst = target.dst.u.udp.port; 157 158 if (target_src != tuple->src.u.udp.port) 159 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP, 160 offsetof(struct udphdr, source), 161 0xFFFF, be16_to_cpu(target_src)); 162 if (target_dst != tuple->dst.u.udp.port) 163 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP, 164 offsetof(struct udphdr, dest), 165 0xFFFF, be16_to_cpu(target_dst)); 166 } 167 168 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct, 169 enum ip_conntrack_dir dir, 170 struct flow_action *action) 171 { 172 struct nf_conn_labels *ct_labels; 173 struct flow_action_entry *entry; 174 enum ip_conntrack_info ctinfo; 175 u32 *act_ct_labels; 176 177 entry = tcf_ct_flow_table_flow_action_get_next(action); 178 entry->id = FLOW_ACTION_CT_METADATA; 179 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 180 entry->ct_metadata.mark = ct->mark; 181 #endif 182 ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED : 183 IP_CT_ESTABLISHED_REPLY; 184 /* aligns with the CT reference on the SKB nf_ct_set */ 185 entry->ct_metadata.cookie = (unsigned long)ct | ctinfo; 186 187 act_ct_labels = entry->ct_metadata.labels; 188 ct_labels = nf_ct_labels_find(ct); 189 if (ct_labels) 190 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE); 191 else 192 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE); 193 } 194 195 static int tcf_ct_flow_table_add_action_nat(struct net *net, 196 struct nf_conn *ct, 197 enum ip_conntrack_dir dir, 198 struct flow_action *action) 199 { 200 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple; 201 struct nf_conntrack_tuple target; 202 203 if (!(ct->status & IPS_NAT_MASK)) 204 return 0; 205 206 nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); 207 208 switch (tuple->src.l3num) { 209 case NFPROTO_IPV4: 210 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target, 211 action); 212 break; 213 case NFPROTO_IPV6: 214 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target, 215 action); 216 break; 217 default: 218 return -EOPNOTSUPP; 219 } 220 221 switch (nf_ct_protonum(ct)) { 222 case IPPROTO_TCP: 223 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action); 224 break; 225 case IPPROTO_UDP: 226 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action); 227 break; 228 default: 229 return -EOPNOTSUPP; 230 } 231 232 return 0; 233 } 234 235 static int tcf_ct_flow_table_fill_actions(struct net *net, 236 const struct flow_offload *flow, 237 enum flow_offload_tuple_dir tdir, 238 struct nf_flow_rule *flow_rule) 239 { 240 struct flow_action *action = &flow_rule->rule->action; 241 int num_entries = action->num_entries; 242 struct nf_conn *ct = flow->ct; 243 enum ip_conntrack_dir dir; 244 int i, err; 245 246 switch (tdir) { 247 case FLOW_OFFLOAD_DIR_ORIGINAL: 248 dir = IP_CT_DIR_ORIGINAL; 249 break; 250 case FLOW_OFFLOAD_DIR_REPLY: 251 dir = IP_CT_DIR_REPLY; 252 break; 253 default: 254 return -EOPNOTSUPP; 255 } 256 257 err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action); 258 if (err) 259 goto err_nat; 260 261 tcf_ct_flow_table_add_action_meta(ct, dir, action); 262 return 0; 263 264 err_nat: 265 /* Clear filled actions */ 266 for (i = num_entries; i < action->num_entries; i++) 267 memset(&action->entries[i], 0, sizeof(action->entries[i])); 268 action->num_entries = num_entries; 269 270 return err; 271 } 272 273 static struct nf_flowtable_type flowtable_ct = { 274 .action = tcf_ct_flow_table_fill_actions, 275 .owner = THIS_MODULE, 276 }; 277 278 static int tcf_ct_flow_table_get(struct tcf_ct_params *params) 279 { 280 struct tcf_ct_flow_table *ct_ft; 281 int err = -ENOMEM; 282 283 mutex_lock(&zones_mutex); 284 ct_ft = rhashtable_lookup_fast(&zones_ht, ¶ms->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 NF_FLOWTABLE_COUNTER; 301 err = nf_flow_table_init(&ct_ft->nf_ft); 302 if (err) 303 goto err_init; 304 305 __module_get(THIS_MODULE); 306 out_unlock: 307 params->ct_ft = ct_ft; 308 params->nf_ft = &ct_ft->nf_ft; 309 mutex_unlock(&zones_mutex); 310 311 return 0; 312 313 err_init: 314 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 315 err_insert: 316 kfree(ct_ft); 317 err_alloc: 318 mutex_unlock(&zones_mutex); 319 return err; 320 } 321 322 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work) 323 { 324 struct tcf_ct_flow_table *ct_ft; 325 326 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table, 327 rwork); 328 nf_flow_table_free(&ct_ft->nf_ft); 329 kfree(ct_ft); 330 331 module_put(THIS_MODULE); 332 } 333 334 static void tcf_ct_flow_table_put(struct tcf_ct_params *params) 335 { 336 struct tcf_ct_flow_table *ct_ft = params->ct_ft; 337 338 if (refcount_dec_and_test(¶ms->ct_ft->ref)) { 339 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 340 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work); 341 queue_rcu_work(act_ct_wq, &ct_ft->rwork); 342 } 343 } 344 345 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft, 346 struct nf_conn *ct, 347 bool tcp) 348 { 349 struct flow_offload *entry; 350 int err; 351 352 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status)) 353 return; 354 355 entry = flow_offload_alloc(ct); 356 if (!entry) { 357 WARN_ON_ONCE(1); 358 goto err_alloc; 359 } 360 361 if (tcp) { 362 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 363 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 364 } 365 366 err = flow_offload_add(&ct_ft->nf_ft, entry); 367 if (err) 368 goto err_add; 369 370 return; 371 372 err_add: 373 flow_offload_free(entry); 374 err_alloc: 375 clear_bit(IPS_OFFLOAD_BIT, &ct->status); 376 } 377 378 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft, 379 struct nf_conn *ct, 380 enum ip_conntrack_info ctinfo) 381 { 382 bool tcp = false; 383 384 if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY) 385 return; 386 387 switch (nf_ct_protonum(ct)) { 388 case IPPROTO_TCP: 389 tcp = true; 390 if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED) 391 return; 392 break; 393 case IPPROTO_UDP: 394 break; 395 default: 396 return; 397 } 398 399 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) || 400 ct->status & IPS_SEQ_ADJUST) 401 return; 402 403 tcf_ct_flow_table_add(ct_ft, ct, tcp); 404 } 405 406 static bool 407 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb, 408 struct flow_offload_tuple *tuple, 409 struct tcphdr **tcph) 410 { 411 struct flow_ports *ports; 412 unsigned int thoff; 413 struct iphdr *iph; 414 415 if (!pskb_network_may_pull(skb, sizeof(*iph))) 416 return false; 417 418 iph = ip_hdr(skb); 419 thoff = iph->ihl * 4; 420 421 if (ip_is_fragment(iph) || 422 unlikely(thoff != sizeof(struct iphdr))) 423 return false; 424 425 if (iph->protocol != IPPROTO_TCP && 426 iph->protocol != IPPROTO_UDP) 427 return false; 428 429 if (iph->ttl <= 1) 430 return false; 431 432 if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ? 433 thoff + sizeof(struct tcphdr) : 434 thoff + sizeof(*ports))) 435 return false; 436 437 iph = ip_hdr(skb); 438 if (iph->protocol == IPPROTO_TCP) 439 *tcph = (void *)(skb_network_header(skb) + thoff); 440 441 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 442 tuple->src_v4.s_addr = iph->saddr; 443 tuple->dst_v4.s_addr = iph->daddr; 444 tuple->src_port = ports->source; 445 tuple->dst_port = ports->dest; 446 tuple->l3proto = AF_INET; 447 tuple->l4proto = iph->protocol; 448 449 return true; 450 } 451 452 static bool 453 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb, 454 struct flow_offload_tuple *tuple, 455 struct tcphdr **tcph) 456 { 457 struct flow_ports *ports; 458 struct ipv6hdr *ip6h; 459 unsigned int thoff; 460 461 if (!pskb_network_may_pull(skb, sizeof(*ip6h))) 462 return false; 463 464 ip6h = ipv6_hdr(skb); 465 466 if (ip6h->nexthdr != IPPROTO_TCP && 467 ip6h->nexthdr != IPPROTO_UDP) 468 return false; 469 470 if (ip6h->hop_limit <= 1) 471 return false; 472 473 thoff = sizeof(*ip6h); 474 if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ? 475 thoff + sizeof(struct tcphdr) : 476 thoff + sizeof(*ports))) 477 return false; 478 479 ip6h = ipv6_hdr(skb); 480 if (ip6h->nexthdr == IPPROTO_TCP) 481 *tcph = (void *)(skb_network_header(skb) + thoff); 482 483 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 484 tuple->src_v6 = ip6h->saddr; 485 tuple->dst_v6 = ip6h->daddr; 486 tuple->src_port = ports->source; 487 tuple->dst_port = ports->dest; 488 tuple->l3proto = AF_INET6; 489 tuple->l4proto = ip6h->nexthdr; 490 491 return true; 492 } 493 494 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p, 495 struct sk_buff *skb, 496 u8 family) 497 { 498 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft; 499 struct flow_offload_tuple_rhash *tuplehash; 500 struct flow_offload_tuple tuple = {}; 501 enum ip_conntrack_info ctinfo; 502 struct tcphdr *tcph = NULL; 503 struct flow_offload *flow; 504 struct nf_conn *ct; 505 u8 dir; 506 507 /* Previously seen or loopback */ 508 ct = nf_ct_get(skb, &ctinfo); 509 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED) 510 return false; 511 512 switch (family) { 513 case NFPROTO_IPV4: 514 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph)) 515 return false; 516 break; 517 case NFPROTO_IPV6: 518 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph)) 519 return false; 520 break; 521 default: 522 return false; 523 } 524 525 tuplehash = flow_offload_lookup(nf_ft, &tuple); 526 if (!tuplehash) 527 return false; 528 529 dir = tuplehash->tuple.dir; 530 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]); 531 ct = flow->ct; 532 533 if (tcph && (unlikely(tcph->fin || tcph->rst))) { 534 flow_offload_teardown(flow); 535 return false; 536 } 537 538 ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED : 539 IP_CT_ESTABLISHED_REPLY; 540 541 flow_offload_refresh(nf_ft, flow); 542 nf_conntrack_get(&ct->ct_general); 543 nf_ct_set(skb, ct, ctinfo); 544 if (nf_ft->flags & NF_FLOWTABLE_COUNTER) 545 nf_ct_acct_update(ct, dir, skb->len); 546 547 return true; 548 } 549 550 static int tcf_ct_flow_tables_init(void) 551 { 552 return rhashtable_init(&zones_ht, &zones_params); 553 } 554 555 static void tcf_ct_flow_tables_uninit(void) 556 { 557 rhashtable_destroy(&zones_ht); 558 } 559 560 static struct tc_action_ops act_ct_ops; 561 static unsigned int ct_net_id; 562 563 struct tc_ct_action_net { 564 struct tc_action_net tn; /* Must be first */ 565 bool labels; 566 }; 567 568 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ 569 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb, 570 u16 zone_id, bool force) 571 { 572 enum ip_conntrack_info ctinfo; 573 struct nf_conn *ct; 574 575 ct = nf_ct_get(skb, &ctinfo); 576 if (!ct) 577 return false; 578 if (!net_eq(net, read_pnet(&ct->ct_net))) 579 return false; 580 if (nf_ct_zone(ct)->id != zone_id) 581 return false; 582 583 /* Force conntrack entry direction. */ 584 if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 585 if (nf_ct_is_confirmed(ct)) 586 nf_ct_kill(ct); 587 588 nf_conntrack_put(&ct->ct_general); 589 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 590 591 return false; 592 } 593 594 return true; 595 } 596 597 /* Trim the skb to the length specified by the IP/IPv6 header, 598 * removing any trailing lower-layer padding. This prepares the skb 599 * for higher-layer processing that assumes skb->len excludes padding 600 * (such as nf_ip_checksum). The caller needs to pull the skb to the 601 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 602 */ 603 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family) 604 { 605 unsigned int len; 606 int err; 607 608 switch (family) { 609 case NFPROTO_IPV4: 610 len = ntohs(ip_hdr(skb)->tot_len); 611 break; 612 case NFPROTO_IPV6: 613 len = sizeof(struct ipv6hdr) 614 + ntohs(ipv6_hdr(skb)->payload_len); 615 break; 616 default: 617 len = skb->len; 618 } 619 620 err = pskb_trim_rcsum(skb, len); 621 622 return err; 623 } 624 625 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb) 626 { 627 u8 family = NFPROTO_UNSPEC; 628 629 switch (skb_protocol(skb, true)) { 630 case htons(ETH_P_IP): 631 family = NFPROTO_IPV4; 632 break; 633 case htons(ETH_P_IPV6): 634 family = NFPROTO_IPV6; 635 break; 636 default: 637 break; 638 } 639 640 return family; 641 } 642 643 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag) 644 { 645 unsigned int len; 646 647 len = skb_network_offset(skb) + sizeof(struct iphdr); 648 if (unlikely(skb->len < len)) 649 return -EINVAL; 650 if (unlikely(!pskb_may_pull(skb, len))) 651 return -ENOMEM; 652 653 *frag = ip_is_fragment(ip_hdr(skb)); 654 return 0; 655 } 656 657 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag) 658 { 659 unsigned int flags = 0, len, payload_ofs = 0; 660 unsigned short frag_off; 661 int nexthdr; 662 663 len = skb_network_offset(skb) + sizeof(struct ipv6hdr); 664 if (unlikely(skb->len < len)) 665 return -EINVAL; 666 if (unlikely(!pskb_may_pull(skb, len))) 667 return -ENOMEM; 668 669 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags); 670 if (unlikely(nexthdr < 0)) 671 return -EPROTO; 672 673 *frag = flags & IP6_FH_F_FRAG; 674 return 0; 675 } 676 677 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 678 u8 family, u16 zone, bool *defrag) 679 { 680 enum ip_conntrack_info ctinfo; 681 struct qdisc_skb_cb cb; 682 struct nf_conn *ct; 683 int err = 0; 684 bool frag; 685 686 /* Previously seen (loopback)? Ignore. */ 687 ct = nf_ct_get(skb, &ctinfo); 688 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED) 689 return 0; 690 691 if (family == NFPROTO_IPV4) 692 err = tcf_ct_ipv4_is_fragment(skb, &frag); 693 else 694 err = tcf_ct_ipv6_is_fragment(skb, &frag); 695 if (err || !frag) 696 return err; 697 698 skb_get(skb); 699 cb = *qdisc_skb_cb(skb); 700 701 if (family == NFPROTO_IPV4) { 702 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; 703 704 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 705 local_bh_disable(); 706 err = ip_defrag(net, skb, user); 707 local_bh_enable(); 708 if (err && err != -EINPROGRESS) 709 return err; 710 711 if (!err) { 712 *defrag = true; 713 cb.mru = IPCB(skb)->frag_max_size; 714 } 715 } else { /* NFPROTO_IPV6 */ 716 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 717 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; 718 719 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); 720 err = nf_ct_frag6_gather(net, skb, user); 721 if (err && err != -EINPROGRESS) 722 goto out_free; 723 724 if (!err) { 725 *defrag = true; 726 cb.mru = IP6CB(skb)->frag_max_size; 727 } 728 #else 729 err = -EOPNOTSUPP; 730 goto out_free; 731 #endif 732 } 733 734 *qdisc_skb_cb(skb) = cb; 735 skb_clear_hash(skb); 736 skb->ignore_df = 1; 737 return err; 738 739 out_free: 740 kfree_skb(skb); 741 return err; 742 } 743 744 static void tcf_ct_params_free(struct rcu_head *head) 745 { 746 struct tcf_ct_params *params = container_of(head, 747 struct tcf_ct_params, rcu); 748 749 tcf_ct_flow_table_put(params); 750 751 if (params->tmpl) 752 nf_conntrack_put(¶ms->tmpl->ct_general); 753 kfree(params); 754 } 755 756 #if IS_ENABLED(CONFIG_NF_NAT) 757 /* Modelled after nf_nat_ipv[46]_fn(). 758 * range is only used for new, uninitialized NAT state. 759 * Returns either NF_ACCEPT or NF_DROP. 760 */ 761 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, 762 enum ip_conntrack_info ctinfo, 763 const struct nf_nat_range2 *range, 764 enum nf_nat_manip_type maniptype) 765 { 766 __be16 proto = skb_protocol(skb, true); 767 int hooknum, err = NF_ACCEPT; 768 769 /* See HOOK2MANIP(). */ 770 if (maniptype == NF_NAT_MANIP_SRC) 771 hooknum = NF_INET_LOCAL_IN; /* Source NAT */ 772 else 773 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ 774 775 switch (ctinfo) { 776 case IP_CT_RELATED: 777 case IP_CT_RELATED_REPLY: 778 if (proto == htons(ETH_P_IP) && 779 ip_hdr(skb)->protocol == IPPROTO_ICMP) { 780 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, 781 hooknum)) 782 err = NF_DROP; 783 goto out; 784 } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) { 785 __be16 frag_off; 786 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 787 int hdrlen = ipv6_skip_exthdr(skb, 788 sizeof(struct ipv6hdr), 789 &nexthdr, &frag_off); 790 791 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { 792 if (!nf_nat_icmpv6_reply_translation(skb, ct, 793 ctinfo, 794 hooknum, 795 hdrlen)) 796 err = NF_DROP; 797 goto out; 798 } 799 } 800 /* Non-ICMP, fall thru to initialize if needed. */ 801 fallthrough; 802 case IP_CT_NEW: 803 /* Seen it before? This can happen for loopback, retrans, 804 * or local packets. 805 */ 806 if (!nf_nat_initialized(ct, maniptype)) { 807 /* Initialize according to the NAT action. */ 808 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) 809 /* Action is set up to establish a new 810 * mapping. 811 */ 812 ? nf_nat_setup_info(ct, range, maniptype) 813 : nf_nat_alloc_null_binding(ct, hooknum); 814 if (err != NF_ACCEPT) 815 goto out; 816 } 817 break; 818 819 case IP_CT_ESTABLISHED: 820 case IP_CT_ESTABLISHED_REPLY: 821 break; 822 823 default: 824 err = NF_DROP; 825 goto out; 826 } 827 828 err = nf_nat_packet(ct, ctinfo, hooknum, skb); 829 out: 830 return err; 831 } 832 #endif /* CONFIG_NF_NAT */ 833 834 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask) 835 { 836 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 837 u32 new_mark; 838 839 if (!mask) 840 return; 841 842 new_mark = mark | (ct->mark & ~(mask)); 843 if (ct->mark != new_mark) { 844 ct->mark = new_mark; 845 if (nf_ct_is_confirmed(ct)) 846 nf_conntrack_event_cache(IPCT_MARK, ct); 847 } 848 #endif 849 } 850 851 static void tcf_ct_act_set_labels(struct nf_conn *ct, 852 u32 *labels, 853 u32 *labels_m) 854 { 855 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) 856 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels); 857 858 if (!memchr_inv(labels_m, 0, labels_sz)) 859 return; 860 861 nf_connlabels_replace(ct, labels, labels_m, 4); 862 #endif 863 } 864 865 static int tcf_ct_act_nat(struct sk_buff *skb, 866 struct nf_conn *ct, 867 enum ip_conntrack_info ctinfo, 868 int ct_action, 869 struct nf_nat_range2 *range, 870 bool commit) 871 { 872 #if IS_ENABLED(CONFIG_NF_NAT) 873 int err; 874 enum nf_nat_manip_type maniptype; 875 876 if (!(ct_action & TCA_CT_ACT_NAT)) 877 return NF_ACCEPT; 878 879 /* Add NAT extension if not confirmed yet. */ 880 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) 881 return NF_DROP; /* Can't NAT. */ 882 883 if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) && 884 (ctinfo != IP_CT_RELATED || commit)) { 885 /* NAT an established or related connection like before. */ 886 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) 887 /* This is the REPLY direction for a connection 888 * for which NAT was applied in the forward 889 * direction. Do the reverse NAT. 890 */ 891 maniptype = ct->status & IPS_SRC_NAT 892 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; 893 else 894 maniptype = ct->status & IPS_SRC_NAT 895 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; 896 } else if (ct_action & TCA_CT_ACT_NAT_SRC) { 897 maniptype = NF_NAT_MANIP_SRC; 898 } else if (ct_action & TCA_CT_ACT_NAT_DST) { 899 maniptype = NF_NAT_MANIP_DST; 900 } else { 901 return NF_ACCEPT; 902 } 903 904 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype); 905 if (err == NF_ACCEPT && 906 ct->status & IPS_SRC_NAT && ct->status & IPS_DST_NAT) { 907 if (maniptype == NF_NAT_MANIP_SRC) 908 maniptype = NF_NAT_MANIP_DST; 909 else 910 maniptype = NF_NAT_MANIP_SRC; 911 912 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype); 913 } 914 return err; 915 #else 916 return NF_ACCEPT; 917 #endif 918 } 919 920 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 921 struct tcf_result *res) 922 { 923 struct net *net = dev_net(skb->dev); 924 bool cached, commit, clear, force; 925 enum ip_conntrack_info ctinfo; 926 struct tcf_ct *c = to_ct(a); 927 struct nf_conn *tmpl = NULL; 928 struct nf_hook_state state; 929 int nh_ofs, err, retval; 930 struct tcf_ct_params *p; 931 bool skip_add = false; 932 bool defrag = false; 933 struct nf_conn *ct; 934 u8 family; 935 936 p = rcu_dereference_bh(c->params); 937 938 retval = READ_ONCE(c->tcf_action); 939 commit = p->ct_action & TCA_CT_ACT_COMMIT; 940 clear = p->ct_action & TCA_CT_ACT_CLEAR; 941 force = p->ct_action & TCA_CT_ACT_FORCE; 942 tmpl = p->tmpl; 943 944 tcf_lastuse_update(&c->tcf_tm); 945 946 if (clear) { 947 ct = nf_ct_get(skb, &ctinfo); 948 if (ct) { 949 nf_conntrack_put(&ct->ct_general); 950 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 951 } 952 953 goto out; 954 } 955 956 family = tcf_ct_skb_nf_family(skb); 957 if (family == NFPROTO_UNSPEC) 958 goto drop; 959 960 /* The conntrack module expects to be working at L3. 961 * We also try to pull the IPv4/6 header to linear area 962 */ 963 nh_ofs = skb_network_offset(skb); 964 skb_pull_rcsum(skb, nh_ofs); 965 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag); 966 if (err == -EINPROGRESS) { 967 retval = TC_ACT_STOLEN; 968 goto out; 969 } 970 if (err) 971 goto drop; 972 973 err = tcf_ct_skb_network_trim(skb, family); 974 if (err) 975 goto drop; 976 977 /* If we are recirculating packets to match on ct fields and 978 * committing with a separate ct action, then we don't need to 979 * actually run the packet through conntrack twice unless it's for a 980 * different zone. 981 */ 982 cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force); 983 if (!cached) { 984 if (!commit && tcf_ct_flow_table_lookup(p, skb, family)) { 985 skip_add = true; 986 goto do_nat; 987 } 988 989 /* Associate skb with specified zone. */ 990 if (tmpl) { 991 ct = nf_ct_get(skb, &ctinfo); 992 if (skb_nfct(skb)) 993 nf_conntrack_put(skb_nfct(skb)); 994 nf_conntrack_get(&tmpl->ct_general); 995 nf_ct_set(skb, tmpl, IP_CT_NEW); 996 } 997 998 state.hook = NF_INET_PRE_ROUTING; 999 state.net = net; 1000 state.pf = family; 1001 err = nf_conntrack_in(skb, &state); 1002 if (err != NF_ACCEPT) 1003 goto out_push; 1004 } 1005 1006 do_nat: 1007 ct = nf_ct_get(skb, &ctinfo); 1008 if (!ct) 1009 goto out_push; 1010 nf_ct_deliver_cached_events(ct); 1011 1012 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit); 1013 if (err != NF_ACCEPT) 1014 goto drop; 1015 1016 if (commit) { 1017 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask); 1018 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask); 1019 1020 /* This will take care of sending queued events 1021 * even if the connection is already confirmed. 1022 */ 1023 nf_conntrack_confirm(skb); 1024 } else if (!skip_add) { 1025 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo); 1026 } 1027 1028 out_push: 1029 skb_push_rcsum(skb, nh_ofs); 1030 1031 out: 1032 tcf_action_update_bstats(&c->common, skb); 1033 if (defrag) 1034 qdisc_skb_cb(skb)->pkt_len = skb->len; 1035 return retval; 1036 1037 drop: 1038 tcf_action_inc_drop_qstats(&c->common); 1039 return TC_ACT_SHOT; 1040 } 1041 1042 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = { 1043 [TCA_CT_ACTION] = { .type = NLA_U16 }, 1044 [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)), 1045 [TCA_CT_ZONE] = { .type = NLA_U16 }, 1046 [TCA_CT_MARK] = { .type = NLA_U32 }, 1047 [TCA_CT_MARK_MASK] = { .type = NLA_U32 }, 1048 [TCA_CT_LABELS] = { .type = NLA_BINARY, 1049 .len = 128 / BITS_PER_BYTE }, 1050 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY, 1051 .len = 128 / BITS_PER_BYTE }, 1052 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 }, 1053 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 }, 1054 [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1055 [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1056 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 }, 1057 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 }, 1058 }; 1059 1060 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p, 1061 struct tc_ct *parm, 1062 struct nlattr **tb, 1063 struct netlink_ext_ack *extack) 1064 { 1065 struct nf_nat_range2 *range; 1066 1067 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1068 return 0; 1069 1070 if (!IS_ENABLED(CONFIG_NF_NAT)) { 1071 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel"); 1072 return -EOPNOTSUPP; 1073 } 1074 1075 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1076 return 0; 1077 1078 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) && 1079 (p->ct_action & TCA_CT_ACT_NAT_DST)) { 1080 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time"); 1081 return -EOPNOTSUPP; 1082 } 1083 1084 range = &p->range; 1085 if (tb[TCA_CT_NAT_IPV4_MIN]) { 1086 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX]; 1087 1088 p->ipv4_range = true; 1089 range->flags |= NF_NAT_RANGE_MAP_IPS; 1090 range->min_addr.ip = 1091 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]); 1092 1093 range->max_addr.ip = max_attr ? 1094 nla_get_in_addr(max_attr) : 1095 range->min_addr.ip; 1096 } else if (tb[TCA_CT_NAT_IPV6_MIN]) { 1097 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX]; 1098 1099 p->ipv4_range = false; 1100 range->flags |= NF_NAT_RANGE_MAP_IPS; 1101 range->min_addr.in6 = 1102 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]); 1103 1104 range->max_addr.in6 = max_attr ? 1105 nla_get_in6_addr(max_attr) : 1106 range->min_addr.in6; 1107 } 1108 1109 if (tb[TCA_CT_NAT_PORT_MIN]) { 1110 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1111 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]); 1112 1113 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ? 1114 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) : 1115 range->min_proto.all; 1116 } 1117 1118 return 0; 1119 } 1120 1121 static void tcf_ct_set_key_val(struct nlattr **tb, 1122 void *val, int val_type, 1123 void *mask, int mask_type, 1124 int len) 1125 { 1126 if (!tb[val_type]) 1127 return; 1128 nla_memcpy(val, tb[val_type], len); 1129 1130 if (!mask) 1131 return; 1132 1133 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type]) 1134 memset(mask, 0xff, len); 1135 else 1136 nla_memcpy(mask, tb[mask_type], len); 1137 } 1138 1139 static int tcf_ct_fill_params(struct net *net, 1140 struct tcf_ct_params *p, 1141 struct tc_ct *parm, 1142 struct nlattr **tb, 1143 struct netlink_ext_ack *extack) 1144 { 1145 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1146 struct nf_conntrack_zone zone; 1147 struct nf_conn *tmpl; 1148 int err; 1149 1150 p->zone = NF_CT_DEFAULT_ZONE_ID; 1151 1152 tcf_ct_set_key_val(tb, 1153 &p->ct_action, TCA_CT_ACTION, 1154 NULL, TCA_CT_UNSPEC, 1155 sizeof(p->ct_action)); 1156 1157 if (p->ct_action & TCA_CT_ACT_CLEAR) 1158 return 0; 1159 1160 err = tcf_ct_fill_params_nat(p, parm, tb, extack); 1161 if (err) 1162 return err; 1163 1164 if (tb[TCA_CT_MARK]) { 1165 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) { 1166 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled."); 1167 return -EOPNOTSUPP; 1168 } 1169 tcf_ct_set_key_val(tb, 1170 &p->mark, TCA_CT_MARK, 1171 &p->mark_mask, TCA_CT_MARK_MASK, 1172 sizeof(p->mark)); 1173 } 1174 1175 if (tb[TCA_CT_LABELS]) { 1176 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) { 1177 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled."); 1178 return -EOPNOTSUPP; 1179 } 1180 1181 if (!tn->labels) { 1182 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length"); 1183 return -EOPNOTSUPP; 1184 } 1185 tcf_ct_set_key_val(tb, 1186 p->labels, TCA_CT_LABELS, 1187 p->labels_mask, TCA_CT_LABELS_MASK, 1188 sizeof(p->labels)); 1189 } 1190 1191 if (tb[TCA_CT_ZONE]) { 1192 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) { 1193 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled."); 1194 return -EOPNOTSUPP; 1195 } 1196 1197 tcf_ct_set_key_val(tb, 1198 &p->zone, TCA_CT_ZONE, 1199 NULL, TCA_CT_UNSPEC, 1200 sizeof(p->zone)); 1201 } 1202 1203 if (p->zone == NF_CT_DEFAULT_ZONE_ID) 1204 return 0; 1205 1206 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0); 1207 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL); 1208 if (!tmpl) { 1209 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template"); 1210 return -ENOMEM; 1211 } 1212 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status); 1213 nf_conntrack_get(&tmpl->ct_general); 1214 p->tmpl = tmpl; 1215 1216 return 0; 1217 } 1218 1219 static int tcf_ct_init(struct net *net, struct nlattr *nla, 1220 struct nlattr *est, struct tc_action **a, 1221 int replace, int bind, bool rtnl_held, 1222 struct tcf_proto *tp, u32 flags, 1223 struct netlink_ext_ack *extack) 1224 { 1225 struct tc_action_net *tn = net_generic(net, ct_net_id); 1226 struct tcf_ct_params *params = NULL; 1227 struct nlattr *tb[TCA_CT_MAX + 1]; 1228 struct tcf_chain *goto_ch = NULL; 1229 struct tc_ct *parm; 1230 struct tcf_ct *c; 1231 int err, res = 0; 1232 u32 index; 1233 1234 if (!nla) { 1235 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed"); 1236 return -EINVAL; 1237 } 1238 1239 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack); 1240 if (err < 0) 1241 return err; 1242 1243 if (!tb[TCA_CT_PARMS]) { 1244 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters"); 1245 return -EINVAL; 1246 } 1247 parm = nla_data(tb[TCA_CT_PARMS]); 1248 index = parm->index; 1249 err = tcf_idr_check_alloc(tn, &index, a, bind); 1250 if (err < 0) 1251 return err; 1252 1253 if (!err) { 1254 err = tcf_idr_create_from_flags(tn, index, est, a, 1255 &act_ct_ops, bind, flags); 1256 if (err) { 1257 tcf_idr_cleanup(tn, index); 1258 return err; 1259 } 1260 res = ACT_P_CREATED; 1261 } else { 1262 if (bind) 1263 return 0; 1264 1265 if (!replace) { 1266 tcf_idr_release(*a, bind); 1267 return -EEXIST; 1268 } 1269 } 1270 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 1271 if (err < 0) 1272 goto cleanup; 1273 1274 c = to_ct(*a); 1275 1276 params = kzalloc(sizeof(*params), GFP_KERNEL); 1277 if (unlikely(!params)) { 1278 err = -ENOMEM; 1279 goto cleanup; 1280 } 1281 1282 err = tcf_ct_fill_params(net, params, parm, tb, extack); 1283 if (err) 1284 goto cleanup; 1285 1286 err = tcf_ct_flow_table_get(params); 1287 if (err) 1288 goto cleanup; 1289 1290 spin_lock_bh(&c->tcf_lock); 1291 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 1292 params = rcu_replace_pointer(c->params, params, 1293 lockdep_is_held(&c->tcf_lock)); 1294 spin_unlock_bh(&c->tcf_lock); 1295 1296 if (goto_ch) 1297 tcf_chain_put_by_act(goto_ch); 1298 if (params) 1299 call_rcu(¶ms->rcu, tcf_ct_params_free); 1300 1301 return res; 1302 1303 cleanup: 1304 if (goto_ch) 1305 tcf_chain_put_by_act(goto_ch); 1306 kfree(params); 1307 tcf_idr_release(*a, bind); 1308 return err; 1309 } 1310 1311 static void tcf_ct_cleanup(struct tc_action *a) 1312 { 1313 struct tcf_ct_params *params; 1314 struct tcf_ct *c = to_ct(a); 1315 1316 params = rcu_dereference_protected(c->params, 1); 1317 if (params) 1318 call_rcu(¶ms->rcu, tcf_ct_params_free); 1319 } 1320 1321 static int tcf_ct_dump_key_val(struct sk_buff *skb, 1322 void *val, int val_type, 1323 void *mask, int mask_type, 1324 int len) 1325 { 1326 int err; 1327 1328 if (mask && !memchr_inv(mask, 0, len)) 1329 return 0; 1330 1331 err = nla_put(skb, val_type, len, val); 1332 if (err) 1333 return err; 1334 1335 if (mask_type != TCA_CT_UNSPEC) { 1336 err = nla_put(skb, mask_type, len, mask); 1337 if (err) 1338 return err; 1339 } 1340 1341 return 0; 1342 } 1343 1344 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p) 1345 { 1346 struct nf_nat_range2 *range = &p->range; 1347 1348 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1349 return 0; 1350 1351 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1352 return 0; 1353 1354 if (range->flags & NF_NAT_RANGE_MAP_IPS) { 1355 if (p->ipv4_range) { 1356 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN, 1357 range->min_addr.ip)) 1358 return -1; 1359 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX, 1360 range->max_addr.ip)) 1361 return -1; 1362 } else { 1363 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN, 1364 &range->min_addr.in6)) 1365 return -1; 1366 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX, 1367 &range->max_addr.in6)) 1368 return -1; 1369 } 1370 } 1371 1372 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) { 1373 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN, 1374 range->min_proto.all)) 1375 return -1; 1376 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX, 1377 range->max_proto.all)) 1378 return -1; 1379 } 1380 1381 return 0; 1382 } 1383 1384 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a, 1385 int bind, int ref) 1386 { 1387 unsigned char *b = skb_tail_pointer(skb); 1388 struct tcf_ct *c = to_ct(a); 1389 struct tcf_ct_params *p; 1390 1391 struct tc_ct opt = { 1392 .index = c->tcf_index, 1393 .refcnt = refcount_read(&c->tcf_refcnt) - ref, 1394 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind, 1395 }; 1396 struct tcf_t t; 1397 1398 spin_lock_bh(&c->tcf_lock); 1399 p = rcu_dereference_protected(c->params, 1400 lockdep_is_held(&c->tcf_lock)); 1401 opt.action = c->tcf_action; 1402 1403 if (tcf_ct_dump_key_val(skb, 1404 &p->ct_action, TCA_CT_ACTION, 1405 NULL, TCA_CT_UNSPEC, 1406 sizeof(p->ct_action))) 1407 goto nla_put_failure; 1408 1409 if (p->ct_action & TCA_CT_ACT_CLEAR) 1410 goto skip_dump; 1411 1412 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1413 tcf_ct_dump_key_val(skb, 1414 &p->mark, TCA_CT_MARK, 1415 &p->mark_mask, TCA_CT_MARK_MASK, 1416 sizeof(p->mark))) 1417 goto nla_put_failure; 1418 1419 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1420 tcf_ct_dump_key_val(skb, 1421 p->labels, TCA_CT_LABELS, 1422 p->labels_mask, TCA_CT_LABELS_MASK, 1423 sizeof(p->labels))) 1424 goto nla_put_failure; 1425 1426 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1427 tcf_ct_dump_key_val(skb, 1428 &p->zone, TCA_CT_ZONE, 1429 NULL, TCA_CT_UNSPEC, 1430 sizeof(p->zone))) 1431 goto nla_put_failure; 1432 1433 if (tcf_ct_dump_nat(skb, p)) 1434 goto nla_put_failure; 1435 1436 skip_dump: 1437 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt)) 1438 goto nla_put_failure; 1439 1440 tcf_tm_dump(&t, &c->tcf_tm); 1441 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD)) 1442 goto nla_put_failure; 1443 spin_unlock_bh(&c->tcf_lock); 1444 1445 return skb->len; 1446 nla_put_failure: 1447 spin_unlock_bh(&c->tcf_lock); 1448 nlmsg_trim(skb, b); 1449 return -1; 1450 } 1451 1452 static int tcf_ct_walker(struct net *net, struct sk_buff *skb, 1453 struct netlink_callback *cb, int type, 1454 const struct tc_action_ops *ops, 1455 struct netlink_ext_ack *extack) 1456 { 1457 struct tc_action_net *tn = net_generic(net, ct_net_id); 1458 1459 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 1460 } 1461 1462 static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index) 1463 { 1464 struct tc_action_net *tn = net_generic(net, ct_net_id); 1465 1466 return tcf_idr_search(tn, a, index); 1467 } 1468 1469 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets, 1470 u64 drops, u64 lastuse, bool hw) 1471 { 1472 struct tcf_ct *c = to_ct(a); 1473 1474 tcf_action_update_stats(a, bytes, packets, drops, hw); 1475 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse); 1476 } 1477 1478 static struct tc_action_ops act_ct_ops = { 1479 .kind = "ct", 1480 .id = TCA_ID_CT, 1481 .owner = THIS_MODULE, 1482 .act = tcf_ct_act, 1483 .dump = tcf_ct_dump, 1484 .init = tcf_ct_init, 1485 .cleanup = tcf_ct_cleanup, 1486 .walk = tcf_ct_walker, 1487 .lookup = tcf_ct_search, 1488 .stats_update = tcf_stats_update, 1489 .size = sizeof(struct tcf_ct), 1490 }; 1491 1492 static __net_init int ct_init_net(struct net *net) 1493 { 1494 unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8; 1495 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1496 1497 if (nf_connlabels_get(net, n_bits - 1)) { 1498 tn->labels = false; 1499 pr_err("act_ct: Failed to set connlabels length"); 1500 } else { 1501 tn->labels = true; 1502 } 1503 1504 return tc_action_net_init(net, &tn->tn, &act_ct_ops); 1505 } 1506 1507 static void __net_exit ct_exit_net(struct list_head *net_list) 1508 { 1509 struct net *net; 1510 1511 rtnl_lock(); 1512 list_for_each_entry(net, net_list, exit_list) { 1513 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1514 1515 if (tn->labels) 1516 nf_connlabels_put(net); 1517 } 1518 rtnl_unlock(); 1519 1520 tc_action_net_exit(net_list, ct_net_id); 1521 } 1522 1523 static struct pernet_operations ct_net_ops = { 1524 .init = ct_init_net, 1525 .exit_batch = ct_exit_net, 1526 .id = &ct_net_id, 1527 .size = sizeof(struct tc_ct_action_net), 1528 }; 1529 1530 static int __init ct_init_module(void) 1531 { 1532 int err; 1533 1534 act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0); 1535 if (!act_ct_wq) 1536 return -ENOMEM; 1537 1538 err = tcf_ct_flow_tables_init(); 1539 if (err) 1540 goto err_tbl_init; 1541 1542 err = tcf_register_action(&act_ct_ops, &ct_net_ops); 1543 if (err) 1544 goto err_register; 1545 1546 static_branch_inc(&tcf_frag_xmit_count); 1547 1548 return 0; 1549 1550 err_register: 1551 tcf_ct_flow_tables_uninit(); 1552 err_tbl_init: 1553 destroy_workqueue(act_ct_wq); 1554 return err; 1555 } 1556 1557 static void __exit ct_cleanup_module(void) 1558 { 1559 static_branch_dec(&tcf_frag_xmit_count); 1560 tcf_unregister_action(&act_ct_ops, &ct_net_ops); 1561 tcf_ct_flow_tables_uninit(); 1562 destroy_workqueue(act_ct_wq); 1563 } 1564 1565 module_init(ct_init_module); 1566 module_exit(ct_cleanup_module); 1567 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>"); 1568 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>"); 1569 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>"); 1570 MODULE_DESCRIPTION("Connection tracking action"); 1571 MODULE_LICENSE("GPL v2"); 1572