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 entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL; 187 188 act_ct_labels = entry->ct_metadata.labels; 189 ct_labels = nf_ct_labels_find(ct); 190 if (ct_labels) 191 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE); 192 else 193 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE); 194 } 195 196 static int tcf_ct_flow_table_add_action_nat(struct net *net, 197 struct nf_conn *ct, 198 enum ip_conntrack_dir dir, 199 struct flow_action *action) 200 { 201 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple; 202 struct nf_conntrack_tuple target; 203 204 if (!(ct->status & IPS_NAT_MASK)) 205 return 0; 206 207 nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); 208 209 switch (tuple->src.l3num) { 210 case NFPROTO_IPV4: 211 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target, 212 action); 213 break; 214 case NFPROTO_IPV6: 215 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target, 216 action); 217 break; 218 default: 219 return -EOPNOTSUPP; 220 } 221 222 switch (nf_ct_protonum(ct)) { 223 case IPPROTO_TCP: 224 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action); 225 break; 226 case IPPROTO_UDP: 227 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action); 228 break; 229 default: 230 return -EOPNOTSUPP; 231 } 232 233 return 0; 234 } 235 236 static int tcf_ct_flow_table_fill_actions(struct net *net, 237 const struct flow_offload *flow, 238 enum flow_offload_tuple_dir tdir, 239 struct nf_flow_rule *flow_rule) 240 { 241 struct flow_action *action = &flow_rule->rule->action; 242 int num_entries = action->num_entries; 243 struct nf_conn *ct = flow->ct; 244 enum ip_conntrack_dir dir; 245 int i, err; 246 247 switch (tdir) { 248 case FLOW_OFFLOAD_DIR_ORIGINAL: 249 dir = IP_CT_DIR_ORIGINAL; 250 break; 251 case FLOW_OFFLOAD_DIR_REPLY: 252 dir = IP_CT_DIR_REPLY; 253 break; 254 default: 255 return -EOPNOTSUPP; 256 } 257 258 err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action); 259 if (err) 260 goto err_nat; 261 262 tcf_ct_flow_table_add_action_meta(ct, dir, action); 263 return 0; 264 265 err_nat: 266 /* Clear filled actions */ 267 for (i = num_entries; i < action->num_entries; i++) 268 memset(&action->entries[i], 0, sizeof(action->entries[i])); 269 action->num_entries = num_entries; 270 271 return err; 272 } 273 274 static struct nf_flowtable_type flowtable_ct = { 275 .action = tcf_ct_flow_table_fill_actions, 276 .owner = THIS_MODULE, 277 }; 278 279 static int tcf_ct_flow_table_get(struct tcf_ct_params *params) 280 { 281 struct tcf_ct_flow_table *ct_ft; 282 int err = -ENOMEM; 283 284 mutex_lock(&zones_mutex); 285 ct_ft = rhashtable_lookup_fast(&zones_ht, ¶ms->zone, zones_params); 286 if (ct_ft && refcount_inc_not_zero(&ct_ft->ref)) 287 goto out_unlock; 288 289 ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL); 290 if (!ct_ft) 291 goto err_alloc; 292 refcount_set(&ct_ft->ref, 1); 293 294 ct_ft->zone = params->zone; 295 err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params); 296 if (err) 297 goto err_insert; 298 299 ct_ft->nf_ft.type = &flowtable_ct; 300 ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD | 301 NF_FLOWTABLE_COUNTER; 302 err = nf_flow_table_init(&ct_ft->nf_ft); 303 if (err) 304 goto err_init; 305 306 __module_get(THIS_MODULE); 307 out_unlock: 308 params->ct_ft = ct_ft; 309 params->nf_ft = &ct_ft->nf_ft; 310 mutex_unlock(&zones_mutex); 311 312 return 0; 313 314 err_init: 315 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 316 err_insert: 317 kfree(ct_ft); 318 err_alloc: 319 mutex_unlock(&zones_mutex); 320 return err; 321 } 322 323 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work) 324 { 325 struct tcf_ct_flow_table *ct_ft; 326 327 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table, 328 rwork); 329 nf_flow_table_free(&ct_ft->nf_ft); 330 kfree(ct_ft); 331 332 module_put(THIS_MODULE); 333 } 334 335 static void tcf_ct_flow_table_put(struct tcf_ct_params *params) 336 { 337 struct tcf_ct_flow_table *ct_ft = params->ct_ft; 338 339 if (refcount_dec_and_test(¶ms->ct_ft->ref)) { 340 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 341 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work); 342 queue_rcu_work(act_ct_wq, &ct_ft->rwork); 343 } 344 } 345 346 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft, 347 struct nf_conn *ct, 348 bool tcp) 349 { 350 struct flow_offload *entry; 351 int err; 352 353 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status)) 354 return; 355 356 entry = flow_offload_alloc(ct); 357 if (!entry) { 358 WARN_ON_ONCE(1); 359 goto err_alloc; 360 } 361 362 if (tcp) { 363 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 364 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 365 } 366 367 err = flow_offload_add(&ct_ft->nf_ft, entry); 368 if (err) 369 goto err_add; 370 371 return; 372 373 err_add: 374 flow_offload_free(entry); 375 err_alloc: 376 clear_bit(IPS_OFFLOAD_BIT, &ct->status); 377 } 378 379 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft, 380 struct nf_conn *ct, 381 enum ip_conntrack_info ctinfo) 382 { 383 bool tcp = false; 384 385 if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY) 386 return; 387 388 switch (nf_ct_protonum(ct)) { 389 case IPPROTO_TCP: 390 tcp = true; 391 if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED) 392 return; 393 break; 394 case IPPROTO_UDP: 395 break; 396 default: 397 return; 398 } 399 400 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) || 401 ct->status & IPS_SEQ_ADJUST) 402 return; 403 404 tcf_ct_flow_table_add(ct_ft, ct, tcp); 405 } 406 407 static bool 408 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb, 409 struct flow_offload_tuple *tuple, 410 struct tcphdr **tcph) 411 { 412 struct flow_ports *ports; 413 unsigned int thoff; 414 struct iphdr *iph; 415 416 if (!pskb_network_may_pull(skb, sizeof(*iph))) 417 return false; 418 419 iph = ip_hdr(skb); 420 thoff = iph->ihl * 4; 421 422 if (ip_is_fragment(iph) || 423 unlikely(thoff != sizeof(struct iphdr))) 424 return false; 425 426 if (iph->protocol != IPPROTO_TCP && 427 iph->protocol != IPPROTO_UDP) 428 return false; 429 430 if (iph->ttl <= 1) 431 return false; 432 433 if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ? 434 thoff + sizeof(struct tcphdr) : 435 thoff + sizeof(*ports))) 436 return false; 437 438 iph = ip_hdr(skb); 439 if (iph->protocol == IPPROTO_TCP) 440 *tcph = (void *)(skb_network_header(skb) + thoff); 441 442 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 443 tuple->src_v4.s_addr = iph->saddr; 444 tuple->dst_v4.s_addr = iph->daddr; 445 tuple->src_port = ports->source; 446 tuple->dst_port = ports->dest; 447 tuple->l3proto = AF_INET; 448 tuple->l4proto = iph->protocol; 449 450 return true; 451 } 452 453 static bool 454 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb, 455 struct flow_offload_tuple *tuple, 456 struct tcphdr **tcph) 457 { 458 struct flow_ports *ports; 459 struct ipv6hdr *ip6h; 460 unsigned int thoff; 461 462 if (!pskb_network_may_pull(skb, sizeof(*ip6h))) 463 return false; 464 465 ip6h = ipv6_hdr(skb); 466 467 if (ip6h->nexthdr != IPPROTO_TCP && 468 ip6h->nexthdr != IPPROTO_UDP) 469 return false; 470 471 if (ip6h->hop_limit <= 1) 472 return false; 473 474 thoff = sizeof(*ip6h); 475 if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ? 476 thoff + sizeof(struct tcphdr) : 477 thoff + sizeof(*ports))) 478 return false; 479 480 ip6h = ipv6_hdr(skb); 481 if (ip6h->nexthdr == IPPROTO_TCP) 482 *tcph = (void *)(skb_network_header(skb) + thoff); 483 484 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 485 tuple->src_v6 = ip6h->saddr; 486 tuple->dst_v6 = ip6h->daddr; 487 tuple->src_port = ports->source; 488 tuple->dst_port = ports->dest; 489 tuple->l3proto = AF_INET6; 490 tuple->l4proto = ip6h->nexthdr; 491 492 return true; 493 } 494 495 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p, 496 struct sk_buff *skb, 497 u8 family) 498 { 499 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft; 500 struct flow_offload_tuple_rhash *tuplehash; 501 struct flow_offload_tuple tuple = {}; 502 enum ip_conntrack_info ctinfo; 503 struct tcphdr *tcph = NULL; 504 struct flow_offload *flow; 505 struct nf_conn *ct; 506 u8 dir; 507 508 /* Previously seen or loopback */ 509 ct = nf_ct_get(skb, &ctinfo); 510 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED) 511 return false; 512 513 switch (family) { 514 case NFPROTO_IPV4: 515 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph)) 516 return false; 517 break; 518 case NFPROTO_IPV6: 519 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph)) 520 return false; 521 break; 522 default: 523 return false; 524 } 525 526 tuplehash = flow_offload_lookup(nf_ft, &tuple); 527 if (!tuplehash) 528 return false; 529 530 dir = tuplehash->tuple.dir; 531 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]); 532 ct = flow->ct; 533 534 if (tcph && (unlikely(tcph->fin || tcph->rst))) { 535 flow_offload_teardown(flow); 536 return false; 537 } 538 539 ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED : 540 IP_CT_ESTABLISHED_REPLY; 541 542 flow_offload_refresh(nf_ft, flow); 543 nf_conntrack_get(&ct->ct_general); 544 nf_ct_set(skb, ct, ctinfo); 545 if (nf_ft->flags & NF_FLOWTABLE_COUNTER) 546 nf_ct_acct_update(ct, dir, skb->len); 547 548 return true; 549 } 550 551 static int tcf_ct_flow_tables_init(void) 552 { 553 return rhashtable_init(&zones_ht, &zones_params); 554 } 555 556 static void tcf_ct_flow_tables_uninit(void) 557 { 558 rhashtable_destroy(&zones_ht); 559 } 560 561 static struct tc_action_ops act_ct_ops; 562 static unsigned int ct_net_id; 563 564 struct tc_ct_action_net { 565 struct tc_action_net tn; /* Must be first */ 566 bool labels; 567 }; 568 569 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ 570 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb, 571 u16 zone_id, bool force) 572 { 573 enum ip_conntrack_info ctinfo; 574 struct nf_conn *ct; 575 576 ct = nf_ct_get(skb, &ctinfo); 577 if (!ct) 578 return false; 579 if (!net_eq(net, read_pnet(&ct->ct_net))) 580 return false; 581 if (nf_ct_zone(ct)->id != zone_id) 582 return false; 583 584 /* Force conntrack entry direction. */ 585 if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 586 if (nf_ct_is_confirmed(ct)) 587 nf_ct_kill(ct); 588 589 nf_conntrack_put(&ct->ct_general); 590 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 591 592 return false; 593 } 594 595 return true; 596 } 597 598 /* Trim the skb to the length specified by the IP/IPv6 header, 599 * removing any trailing lower-layer padding. This prepares the skb 600 * for higher-layer processing that assumes skb->len excludes padding 601 * (such as nf_ip_checksum). The caller needs to pull the skb to the 602 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 603 */ 604 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family) 605 { 606 unsigned int len; 607 int err; 608 609 switch (family) { 610 case NFPROTO_IPV4: 611 len = ntohs(ip_hdr(skb)->tot_len); 612 break; 613 case NFPROTO_IPV6: 614 len = sizeof(struct ipv6hdr) 615 + ntohs(ipv6_hdr(skb)->payload_len); 616 break; 617 default: 618 len = skb->len; 619 } 620 621 err = pskb_trim_rcsum(skb, len); 622 623 return err; 624 } 625 626 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb) 627 { 628 u8 family = NFPROTO_UNSPEC; 629 630 switch (skb_protocol(skb, true)) { 631 case htons(ETH_P_IP): 632 family = NFPROTO_IPV4; 633 break; 634 case htons(ETH_P_IPV6): 635 family = NFPROTO_IPV6; 636 break; 637 default: 638 break; 639 } 640 641 return family; 642 } 643 644 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag) 645 { 646 unsigned int len; 647 648 len = skb_network_offset(skb) + sizeof(struct iphdr); 649 if (unlikely(skb->len < len)) 650 return -EINVAL; 651 if (unlikely(!pskb_may_pull(skb, len))) 652 return -ENOMEM; 653 654 *frag = ip_is_fragment(ip_hdr(skb)); 655 return 0; 656 } 657 658 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag) 659 { 660 unsigned int flags = 0, len, payload_ofs = 0; 661 unsigned short frag_off; 662 int nexthdr; 663 664 len = skb_network_offset(skb) + sizeof(struct ipv6hdr); 665 if (unlikely(skb->len < len)) 666 return -EINVAL; 667 if (unlikely(!pskb_may_pull(skb, len))) 668 return -ENOMEM; 669 670 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags); 671 if (unlikely(nexthdr < 0)) 672 return -EPROTO; 673 674 *frag = flags & IP6_FH_F_FRAG; 675 return 0; 676 } 677 678 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 679 u8 family, u16 zone, bool *defrag) 680 { 681 enum ip_conntrack_info ctinfo; 682 struct qdisc_skb_cb cb; 683 struct nf_conn *ct; 684 int err = 0; 685 bool frag; 686 687 /* Previously seen (loopback)? Ignore. */ 688 ct = nf_ct_get(skb, &ctinfo); 689 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED) 690 return 0; 691 692 if (family == NFPROTO_IPV4) 693 err = tcf_ct_ipv4_is_fragment(skb, &frag); 694 else 695 err = tcf_ct_ipv6_is_fragment(skb, &frag); 696 if (err || !frag) 697 return err; 698 699 skb_get(skb); 700 cb = *qdisc_skb_cb(skb); 701 702 if (family == NFPROTO_IPV4) { 703 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; 704 705 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 706 local_bh_disable(); 707 err = ip_defrag(net, skb, user); 708 local_bh_enable(); 709 if (err && err != -EINPROGRESS) 710 return err; 711 712 if (!err) { 713 *defrag = true; 714 cb.mru = IPCB(skb)->frag_max_size; 715 } 716 } else { /* NFPROTO_IPV6 */ 717 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 718 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; 719 720 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); 721 err = nf_ct_frag6_gather(net, skb, user); 722 if (err && err != -EINPROGRESS) 723 goto out_free; 724 725 if (!err) { 726 *defrag = true; 727 cb.mru = IP6CB(skb)->frag_max_size; 728 } 729 #else 730 err = -EOPNOTSUPP; 731 goto out_free; 732 #endif 733 } 734 735 if (err != -EINPROGRESS) 736 *qdisc_skb_cb(skb) = cb; 737 skb_clear_hash(skb); 738 skb->ignore_df = 1; 739 return err; 740 741 out_free: 742 kfree_skb(skb); 743 return err; 744 } 745 746 static void tcf_ct_params_free(struct rcu_head *head) 747 { 748 struct tcf_ct_params *params = container_of(head, 749 struct tcf_ct_params, rcu); 750 751 tcf_ct_flow_table_put(params); 752 753 if (params->tmpl) 754 nf_conntrack_put(¶ms->tmpl->ct_general); 755 kfree(params); 756 } 757 758 #if IS_ENABLED(CONFIG_NF_NAT) 759 /* Modelled after nf_nat_ipv[46]_fn(). 760 * range is only used for new, uninitialized NAT state. 761 * Returns either NF_ACCEPT or NF_DROP. 762 */ 763 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, 764 enum ip_conntrack_info ctinfo, 765 const struct nf_nat_range2 *range, 766 enum nf_nat_manip_type maniptype) 767 { 768 __be16 proto = skb_protocol(skb, true); 769 int hooknum, err = NF_ACCEPT; 770 771 /* See HOOK2MANIP(). */ 772 if (maniptype == NF_NAT_MANIP_SRC) 773 hooknum = NF_INET_LOCAL_IN; /* Source NAT */ 774 else 775 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ 776 777 switch (ctinfo) { 778 case IP_CT_RELATED: 779 case IP_CT_RELATED_REPLY: 780 if (proto == htons(ETH_P_IP) && 781 ip_hdr(skb)->protocol == IPPROTO_ICMP) { 782 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, 783 hooknum)) 784 err = NF_DROP; 785 goto out; 786 } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) { 787 __be16 frag_off; 788 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 789 int hdrlen = ipv6_skip_exthdr(skb, 790 sizeof(struct ipv6hdr), 791 &nexthdr, &frag_off); 792 793 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { 794 if (!nf_nat_icmpv6_reply_translation(skb, ct, 795 ctinfo, 796 hooknum, 797 hdrlen)) 798 err = NF_DROP; 799 goto out; 800 } 801 } 802 /* Non-ICMP, fall thru to initialize if needed. */ 803 fallthrough; 804 case IP_CT_NEW: 805 /* Seen it before? This can happen for loopback, retrans, 806 * or local packets. 807 */ 808 if (!nf_nat_initialized(ct, maniptype)) { 809 /* Initialize according to the NAT action. */ 810 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) 811 /* Action is set up to establish a new 812 * mapping. 813 */ 814 ? nf_nat_setup_info(ct, range, maniptype) 815 : nf_nat_alloc_null_binding(ct, hooknum); 816 if (err != NF_ACCEPT) 817 goto out; 818 } 819 break; 820 821 case IP_CT_ESTABLISHED: 822 case IP_CT_ESTABLISHED_REPLY: 823 break; 824 825 default: 826 err = NF_DROP; 827 goto out; 828 } 829 830 err = nf_nat_packet(ct, ctinfo, hooknum, skb); 831 out: 832 return err; 833 } 834 #endif /* CONFIG_NF_NAT */ 835 836 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask) 837 { 838 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 839 u32 new_mark; 840 841 if (!mask) 842 return; 843 844 new_mark = mark | (ct->mark & ~(mask)); 845 if (ct->mark != new_mark) { 846 ct->mark = new_mark; 847 if (nf_ct_is_confirmed(ct)) 848 nf_conntrack_event_cache(IPCT_MARK, ct); 849 } 850 #endif 851 } 852 853 static void tcf_ct_act_set_labels(struct nf_conn *ct, 854 u32 *labels, 855 u32 *labels_m) 856 { 857 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) 858 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels); 859 860 if (!memchr_inv(labels_m, 0, labels_sz)) 861 return; 862 863 nf_connlabels_replace(ct, labels, labels_m, 4); 864 #endif 865 } 866 867 static int tcf_ct_act_nat(struct sk_buff *skb, 868 struct nf_conn *ct, 869 enum ip_conntrack_info ctinfo, 870 int ct_action, 871 struct nf_nat_range2 *range, 872 bool commit) 873 { 874 #if IS_ENABLED(CONFIG_NF_NAT) 875 int err; 876 enum nf_nat_manip_type maniptype; 877 878 if (!(ct_action & TCA_CT_ACT_NAT)) 879 return NF_ACCEPT; 880 881 /* Add NAT extension if not confirmed yet. */ 882 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) 883 return NF_DROP; /* Can't NAT. */ 884 885 if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) && 886 (ctinfo != IP_CT_RELATED || commit)) { 887 /* NAT an established or related connection like before. */ 888 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) 889 /* This is the REPLY direction for a connection 890 * for which NAT was applied in the forward 891 * direction. Do the reverse NAT. 892 */ 893 maniptype = ct->status & IPS_SRC_NAT 894 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; 895 else 896 maniptype = ct->status & IPS_SRC_NAT 897 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; 898 } else if (ct_action & TCA_CT_ACT_NAT_SRC) { 899 maniptype = NF_NAT_MANIP_SRC; 900 } else if (ct_action & TCA_CT_ACT_NAT_DST) { 901 maniptype = NF_NAT_MANIP_DST; 902 } else { 903 return NF_ACCEPT; 904 } 905 906 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype); 907 if (err == NF_ACCEPT && 908 ct->status & IPS_SRC_NAT && ct->status & IPS_DST_NAT) { 909 if (maniptype == NF_NAT_MANIP_SRC) 910 maniptype = NF_NAT_MANIP_DST; 911 else 912 maniptype = NF_NAT_MANIP_SRC; 913 914 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype); 915 } 916 return err; 917 #else 918 return NF_ACCEPT; 919 #endif 920 } 921 922 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 923 struct tcf_result *res) 924 { 925 struct net *net = dev_net(skb->dev); 926 bool cached, commit, clear, force; 927 enum ip_conntrack_info ctinfo; 928 struct tcf_ct *c = to_ct(a); 929 struct nf_conn *tmpl = NULL; 930 struct nf_hook_state state; 931 int nh_ofs, err, retval; 932 struct tcf_ct_params *p; 933 bool skip_add = false; 934 bool defrag = false; 935 struct nf_conn *ct; 936 u8 family; 937 938 p = rcu_dereference_bh(c->params); 939 940 retval = READ_ONCE(c->tcf_action); 941 commit = p->ct_action & TCA_CT_ACT_COMMIT; 942 clear = p->ct_action & TCA_CT_ACT_CLEAR; 943 force = p->ct_action & TCA_CT_ACT_FORCE; 944 tmpl = p->tmpl; 945 946 tcf_lastuse_update(&c->tcf_tm); 947 948 if (clear) { 949 qdisc_skb_cb(skb)->post_ct = false; 950 ct = nf_ct_get(skb, &ctinfo); 951 if (ct) { 952 nf_conntrack_put(&ct->ct_general); 953 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 954 } 955 956 goto out_clear; 957 } 958 959 family = tcf_ct_skb_nf_family(skb); 960 if (family == NFPROTO_UNSPEC) 961 goto drop; 962 963 /* The conntrack module expects to be working at L3. 964 * We also try to pull the IPv4/6 header to linear area 965 */ 966 nh_ofs = skb_network_offset(skb); 967 skb_pull_rcsum(skb, nh_ofs); 968 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag); 969 if (err == -EINPROGRESS) { 970 retval = TC_ACT_STOLEN; 971 goto out_clear; 972 } 973 if (err) 974 goto drop; 975 976 err = tcf_ct_skb_network_trim(skb, family); 977 if (err) 978 goto drop; 979 980 /* If we are recirculating packets to match on ct fields and 981 * committing with a separate ct action, then we don't need to 982 * actually run the packet through conntrack twice unless it's for a 983 * different zone. 984 */ 985 cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force); 986 if (!cached) { 987 if (tcf_ct_flow_table_lookup(p, skb, family)) { 988 skip_add = true; 989 goto do_nat; 990 } 991 992 /* Associate skb with specified zone. */ 993 if (tmpl) { 994 nf_conntrack_put(skb_nfct(skb)); 995 nf_conntrack_get(&tmpl->ct_general); 996 nf_ct_set(skb, tmpl, IP_CT_NEW); 997 } 998 999 state.hook = NF_INET_PRE_ROUTING; 1000 state.net = net; 1001 state.pf = family; 1002 err = nf_conntrack_in(skb, &state); 1003 if (err != NF_ACCEPT) 1004 goto out_push; 1005 } 1006 1007 do_nat: 1008 ct = nf_ct_get(skb, &ctinfo); 1009 if (!ct) 1010 goto out_push; 1011 nf_ct_deliver_cached_events(ct); 1012 1013 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit); 1014 if (err != NF_ACCEPT) 1015 goto drop; 1016 1017 if (commit) { 1018 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask); 1019 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask); 1020 1021 /* This will take care of sending queued events 1022 * even if the connection is already confirmed. 1023 */ 1024 nf_conntrack_confirm(skb); 1025 } 1026 1027 if (!skip_add) 1028 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo); 1029 1030 out_push: 1031 skb_push_rcsum(skb, nh_ofs); 1032 1033 qdisc_skb_cb(skb)->post_ct = true; 1034 out_clear: 1035 tcf_action_update_bstats(&c->common, skb); 1036 if (defrag) 1037 qdisc_skb_cb(skb)->pkt_len = skb->len; 1038 return retval; 1039 1040 drop: 1041 tcf_action_inc_drop_qstats(&c->common); 1042 return TC_ACT_SHOT; 1043 } 1044 1045 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = { 1046 [TCA_CT_ACTION] = { .type = NLA_U16 }, 1047 [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)), 1048 [TCA_CT_ZONE] = { .type = NLA_U16 }, 1049 [TCA_CT_MARK] = { .type = NLA_U32 }, 1050 [TCA_CT_MARK_MASK] = { .type = NLA_U32 }, 1051 [TCA_CT_LABELS] = { .type = NLA_BINARY, 1052 .len = 128 / BITS_PER_BYTE }, 1053 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY, 1054 .len = 128 / BITS_PER_BYTE }, 1055 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 }, 1056 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 }, 1057 [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1058 [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1059 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 }, 1060 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 }, 1061 }; 1062 1063 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p, 1064 struct tc_ct *parm, 1065 struct nlattr **tb, 1066 struct netlink_ext_ack *extack) 1067 { 1068 struct nf_nat_range2 *range; 1069 1070 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1071 return 0; 1072 1073 if (!IS_ENABLED(CONFIG_NF_NAT)) { 1074 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel"); 1075 return -EOPNOTSUPP; 1076 } 1077 1078 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1079 return 0; 1080 1081 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) && 1082 (p->ct_action & TCA_CT_ACT_NAT_DST)) { 1083 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time"); 1084 return -EOPNOTSUPP; 1085 } 1086 1087 range = &p->range; 1088 if (tb[TCA_CT_NAT_IPV4_MIN]) { 1089 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX]; 1090 1091 p->ipv4_range = true; 1092 range->flags |= NF_NAT_RANGE_MAP_IPS; 1093 range->min_addr.ip = 1094 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]); 1095 1096 range->max_addr.ip = max_attr ? 1097 nla_get_in_addr(max_attr) : 1098 range->min_addr.ip; 1099 } else if (tb[TCA_CT_NAT_IPV6_MIN]) { 1100 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX]; 1101 1102 p->ipv4_range = false; 1103 range->flags |= NF_NAT_RANGE_MAP_IPS; 1104 range->min_addr.in6 = 1105 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]); 1106 1107 range->max_addr.in6 = max_attr ? 1108 nla_get_in6_addr(max_attr) : 1109 range->min_addr.in6; 1110 } 1111 1112 if (tb[TCA_CT_NAT_PORT_MIN]) { 1113 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1114 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]); 1115 1116 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ? 1117 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) : 1118 range->min_proto.all; 1119 } 1120 1121 return 0; 1122 } 1123 1124 static void tcf_ct_set_key_val(struct nlattr **tb, 1125 void *val, int val_type, 1126 void *mask, int mask_type, 1127 int len) 1128 { 1129 if (!tb[val_type]) 1130 return; 1131 nla_memcpy(val, tb[val_type], len); 1132 1133 if (!mask) 1134 return; 1135 1136 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type]) 1137 memset(mask, 0xff, len); 1138 else 1139 nla_memcpy(mask, tb[mask_type], len); 1140 } 1141 1142 static int tcf_ct_fill_params(struct net *net, 1143 struct tcf_ct_params *p, 1144 struct tc_ct *parm, 1145 struct nlattr **tb, 1146 struct netlink_ext_ack *extack) 1147 { 1148 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1149 struct nf_conntrack_zone zone; 1150 struct nf_conn *tmpl; 1151 int err; 1152 1153 p->zone = NF_CT_DEFAULT_ZONE_ID; 1154 1155 tcf_ct_set_key_val(tb, 1156 &p->ct_action, TCA_CT_ACTION, 1157 NULL, TCA_CT_UNSPEC, 1158 sizeof(p->ct_action)); 1159 1160 if (p->ct_action & TCA_CT_ACT_CLEAR) 1161 return 0; 1162 1163 err = tcf_ct_fill_params_nat(p, parm, tb, extack); 1164 if (err) 1165 return err; 1166 1167 if (tb[TCA_CT_MARK]) { 1168 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) { 1169 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled."); 1170 return -EOPNOTSUPP; 1171 } 1172 tcf_ct_set_key_val(tb, 1173 &p->mark, TCA_CT_MARK, 1174 &p->mark_mask, TCA_CT_MARK_MASK, 1175 sizeof(p->mark)); 1176 } 1177 1178 if (tb[TCA_CT_LABELS]) { 1179 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) { 1180 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled."); 1181 return -EOPNOTSUPP; 1182 } 1183 1184 if (!tn->labels) { 1185 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length"); 1186 return -EOPNOTSUPP; 1187 } 1188 tcf_ct_set_key_val(tb, 1189 p->labels, TCA_CT_LABELS, 1190 p->labels_mask, TCA_CT_LABELS_MASK, 1191 sizeof(p->labels)); 1192 } 1193 1194 if (tb[TCA_CT_ZONE]) { 1195 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) { 1196 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled."); 1197 return -EOPNOTSUPP; 1198 } 1199 1200 tcf_ct_set_key_val(tb, 1201 &p->zone, TCA_CT_ZONE, 1202 NULL, TCA_CT_UNSPEC, 1203 sizeof(p->zone)); 1204 } 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