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 <net/netfilter/nf_conntrack_act_ct.h> 36 #include <uapi/linux/netfilter/nf_nat.h> 37 38 static struct workqueue_struct *act_ct_wq; 39 static struct rhashtable zones_ht; 40 static DEFINE_MUTEX(zones_mutex); 41 42 struct tcf_ct_flow_table { 43 struct rhash_head node; /* In zones tables */ 44 45 struct rcu_work rwork; 46 struct nf_flowtable nf_ft; 47 refcount_t ref; 48 u16 zone; 49 50 bool dying; 51 }; 52 53 static const struct rhashtable_params zones_params = { 54 .head_offset = offsetof(struct tcf_ct_flow_table, node), 55 .key_offset = offsetof(struct tcf_ct_flow_table, zone), 56 .key_len = sizeof_field(struct tcf_ct_flow_table, zone), 57 .automatic_shrinking = true, 58 }; 59 60 static struct flow_action_entry * 61 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action) 62 { 63 int i = flow_action->num_entries++; 64 65 return &flow_action->entries[i]; 66 } 67 68 static void tcf_ct_add_mangle_action(struct flow_action *action, 69 enum flow_action_mangle_base htype, 70 u32 offset, 71 u32 mask, 72 u32 val) 73 { 74 struct flow_action_entry *entry; 75 76 entry = tcf_ct_flow_table_flow_action_get_next(action); 77 entry->id = FLOW_ACTION_MANGLE; 78 entry->mangle.htype = htype; 79 entry->mangle.mask = ~mask; 80 entry->mangle.offset = offset; 81 entry->mangle.val = val; 82 } 83 84 /* The following nat helper functions check if the inverted reverse tuple 85 * (target) is different then the current dir tuple - meaning nat for ports 86 * and/or ip is needed, and add the relevant mangle actions. 87 */ 88 static void 89 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple, 90 struct nf_conntrack_tuple target, 91 struct flow_action *action) 92 { 93 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) 94 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, 95 offsetof(struct iphdr, saddr), 96 0xFFFFFFFF, 97 be32_to_cpu(target.src.u3.ip)); 98 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) 99 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, 100 offsetof(struct iphdr, daddr), 101 0xFFFFFFFF, 102 be32_to_cpu(target.dst.u3.ip)); 103 } 104 105 static void 106 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action, 107 union nf_inet_addr *addr, 108 u32 offset) 109 { 110 int i; 111 112 for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++) 113 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6, 114 i * sizeof(u32) + offset, 115 0xFFFFFFFF, be32_to_cpu(addr->ip6[i])); 116 } 117 118 static void 119 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple, 120 struct nf_conntrack_tuple target, 121 struct flow_action *action) 122 { 123 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) 124 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3, 125 offsetof(struct ipv6hdr, 126 saddr)); 127 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) 128 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3, 129 offsetof(struct ipv6hdr, 130 daddr)); 131 } 132 133 static void 134 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple, 135 struct nf_conntrack_tuple target, 136 struct flow_action *action) 137 { 138 __be16 target_src = target.src.u.tcp.port; 139 __be16 target_dst = target.dst.u.tcp.port; 140 141 if (target_src != tuple->src.u.tcp.port) 142 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, 143 offsetof(struct tcphdr, source), 144 0xFFFF, be16_to_cpu(target_src)); 145 if (target_dst != tuple->dst.u.tcp.port) 146 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, 147 offsetof(struct tcphdr, dest), 148 0xFFFF, be16_to_cpu(target_dst)); 149 } 150 151 static void 152 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple, 153 struct nf_conntrack_tuple target, 154 struct flow_action *action) 155 { 156 __be16 target_src = target.src.u.udp.port; 157 __be16 target_dst = target.dst.u.udp.port; 158 159 if (target_src != tuple->src.u.udp.port) 160 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP, 161 offsetof(struct udphdr, source), 162 0xFFFF, be16_to_cpu(target_src)); 163 if (target_dst != tuple->dst.u.udp.port) 164 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP, 165 offsetof(struct udphdr, dest), 166 0xFFFF, be16_to_cpu(target_dst)); 167 } 168 169 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct, 170 enum ip_conntrack_dir dir, 171 struct flow_action *action) 172 { 173 struct nf_conn_labels *ct_labels; 174 struct flow_action_entry *entry; 175 enum ip_conntrack_info ctinfo; 176 u32 *act_ct_labels; 177 178 entry = tcf_ct_flow_table_flow_action_get_next(action); 179 entry->id = FLOW_ACTION_CT_METADATA; 180 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 181 entry->ct_metadata.mark = ct->mark; 182 #endif 183 ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED : 184 IP_CT_ESTABLISHED_REPLY; 185 /* aligns with the CT reference on the SKB nf_ct_set */ 186 entry->ct_metadata.cookie = (unsigned long)ct | ctinfo; 187 entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL; 188 189 act_ct_labels = entry->ct_metadata.labels; 190 ct_labels = nf_ct_labels_find(ct); 191 if (ct_labels) 192 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE); 193 else 194 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE); 195 } 196 197 static int tcf_ct_flow_table_add_action_nat(struct net *net, 198 struct nf_conn *ct, 199 enum ip_conntrack_dir dir, 200 struct flow_action *action) 201 { 202 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple; 203 struct nf_conntrack_tuple target; 204 205 if (!(ct->status & IPS_NAT_MASK)) 206 return 0; 207 208 nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); 209 210 switch (tuple->src.l3num) { 211 case NFPROTO_IPV4: 212 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target, 213 action); 214 break; 215 case NFPROTO_IPV6: 216 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target, 217 action); 218 break; 219 default: 220 return -EOPNOTSUPP; 221 } 222 223 switch (nf_ct_protonum(ct)) { 224 case IPPROTO_TCP: 225 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action); 226 break; 227 case IPPROTO_UDP: 228 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action); 229 break; 230 default: 231 return -EOPNOTSUPP; 232 } 233 234 return 0; 235 } 236 237 static int tcf_ct_flow_table_fill_actions(struct net *net, 238 const struct flow_offload *flow, 239 enum flow_offload_tuple_dir tdir, 240 struct nf_flow_rule *flow_rule) 241 { 242 struct flow_action *action = &flow_rule->rule->action; 243 int num_entries = action->num_entries; 244 struct nf_conn *ct = flow->ct; 245 enum ip_conntrack_dir dir; 246 int i, err; 247 248 switch (tdir) { 249 case FLOW_OFFLOAD_DIR_ORIGINAL: 250 dir = IP_CT_DIR_ORIGINAL; 251 break; 252 case FLOW_OFFLOAD_DIR_REPLY: 253 dir = IP_CT_DIR_REPLY; 254 break; 255 default: 256 return -EOPNOTSUPP; 257 } 258 259 err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action); 260 if (err) 261 goto err_nat; 262 263 tcf_ct_flow_table_add_action_meta(ct, dir, action); 264 return 0; 265 266 err_nat: 267 /* Clear filled actions */ 268 for (i = num_entries; i < action->num_entries; i++) 269 memset(&action->entries[i], 0, sizeof(action->entries[i])); 270 action->num_entries = num_entries; 271 272 return err; 273 } 274 275 static struct nf_flowtable_type flowtable_ct = { 276 .action = tcf_ct_flow_table_fill_actions, 277 .owner = THIS_MODULE, 278 }; 279 280 static int tcf_ct_flow_table_get(struct tcf_ct_params *params) 281 { 282 struct tcf_ct_flow_table *ct_ft; 283 int err = -ENOMEM; 284 285 mutex_lock(&zones_mutex); 286 ct_ft = rhashtable_lookup_fast(&zones_ht, ¶ms->zone, zones_params); 287 if (ct_ft && refcount_inc_not_zero(&ct_ft->ref)) 288 goto out_unlock; 289 290 ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL); 291 if (!ct_ft) 292 goto err_alloc; 293 refcount_set(&ct_ft->ref, 1); 294 295 ct_ft->zone = params->zone; 296 err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params); 297 if (err) 298 goto err_insert; 299 300 ct_ft->nf_ft.type = &flowtable_ct; 301 ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD | 302 NF_FLOWTABLE_COUNTER; 303 err = nf_flow_table_init(&ct_ft->nf_ft); 304 if (err) 305 goto err_init; 306 307 __module_get(THIS_MODULE); 308 out_unlock: 309 params->ct_ft = ct_ft; 310 params->nf_ft = &ct_ft->nf_ft; 311 mutex_unlock(&zones_mutex); 312 313 return 0; 314 315 err_init: 316 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 317 err_insert: 318 kfree(ct_ft); 319 err_alloc: 320 mutex_unlock(&zones_mutex); 321 return err; 322 } 323 324 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work) 325 { 326 struct flow_block_cb *block_cb, *tmp_cb; 327 struct tcf_ct_flow_table *ct_ft; 328 struct flow_block *block; 329 330 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table, 331 rwork); 332 nf_flow_table_free(&ct_ft->nf_ft); 333 334 /* Remove any remaining callbacks before cleanup */ 335 block = &ct_ft->nf_ft.flow_block; 336 down_write(&ct_ft->nf_ft.flow_block_lock); 337 list_for_each_entry_safe(block_cb, tmp_cb, &block->cb_list, list) { 338 list_del(&block_cb->list); 339 flow_block_cb_free(block_cb); 340 } 341 up_write(&ct_ft->nf_ft.flow_block_lock); 342 kfree(ct_ft); 343 344 module_put(THIS_MODULE); 345 } 346 347 static void tcf_ct_flow_table_put(struct tcf_ct_params *params) 348 { 349 struct tcf_ct_flow_table *ct_ft = params->ct_ft; 350 351 if (refcount_dec_and_test(¶ms->ct_ft->ref)) { 352 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 353 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work); 354 queue_rcu_work(act_ct_wq, &ct_ft->rwork); 355 } 356 } 357 358 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft, 359 struct nf_conn *ct, 360 bool tcp) 361 { 362 struct nf_conn_act_ct_ext *act_ct_ext; 363 struct flow_offload *entry; 364 int err; 365 366 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status)) 367 return; 368 369 entry = flow_offload_alloc(ct); 370 if (!entry) { 371 WARN_ON_ONCE(1); 372 goto err_alloc; 373 } 374 375 if (tcp) { 376 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 377 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 378 } 379 380 act_ct_ext = nf_conn_act_ct_ext_find(ct); 381 if (act_ct_ext) { 382 entry->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.iifidx = 383 act_ct_ext->ifindex[IP_CT_DIR_ORIGINAL]; 384 entry->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.iifidx = 385 act_ct_ext->ifindex[IP_CT_DIR_REPLY]; 386 } 387 388 err = flow_offload_add(&ct_ft->nf_ft, entry); 389 if (err) 390 goto err_add; 391 392 return; 393 394 err_add: 395 flow_offload_free(entry); 396 err_alloc: 397 clear_bit(IPS_OFFLOAD_BIT, &ct->status); 398 } 399 400 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft, 401 struct nf_conn *ct, 402 enum ip_conntrack_info ctinfo) 403 { 404 bool tcp = false; 405 406 if ((ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY) || 407 !test_bit(IPS_ASSURED_BIT, &ct->status)) 408 return; 409 410 switch (nf_ct_protonum(ct)) { 411 case IPPROTO_TCP: 412 tcp = true; 413 if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED) 414 return; 415 break; 416 case IPPROTO_UDP: 417 break; 418 default: 419 return; 420 } 421 422 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) || 423 ct->status & IPS_SEQ_ADJUST) 424 return; 425 426 tcf_ct_flow_table_add(ct_ft, ct, tcp); 427 } 428 429 static bool 430 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb, 431 struct flow_offload_tuple *tuple, 432 struct tcphdr **tcph) 433 { 434 struct flow_ports *ports; 435 unsigned int thoff; 436 struct iphdr *iph; 437 438 if (!pskb_network_may_pull(skb, sizeof(*iph))) 439 return false; 440 441 iph = ip_hdr(skb); 442 thoff = iph->ihl * 4; 443 444 if (ip_is_fragment(iph) || 445 unlikely(thoff != sizeof(struct iphdr))) 446 return false; 447 448 if (iph->protocol != IPPROTO_TCP && 449 iph->protocol != IPPROTO_UDP) 450 return false; 451 452 if (iph->ttl <= 1) 453 return false; 454 455 if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ? 456 thoff + sizeof(struct tcphdr) : 457 thoff + sizeof(*ports))) 458 return false; 459 460 iph = ip_hdr(skb); 461 if (iph->protocol == IPPROTO_TCP) 462 *tcph = (void *)(skb_network_header(skb) + thoff); 463 464 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 465 tuple->src_v4.s_addr = iph->saddr; 466 tuple->dst_v4.s_addr = iph->daddr; 467 tuple->src_port = ports->source; 468 tuple->dst_port = ports->dest; 469 tuple->l3proto = AF_INET; 470 tuple->l4proto = iph->protocol; 471 472 return true; 473 } 474 475 static bool 476 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb, 477 struct flow_offload_tuple *tuple, 478 struct tcphdr **tcph) 479 { 480 struct flow_ports *ports; 481 struct ipv6hdr *ip6h; 482 unsigned int thoff; 483 484 if (!pskb_network_may_pull(skb, sizeof(*ip6h))) 485 return false; 486 487 ip6h = ipv6_hdr(skb); 488 489 if (ip6h->nexthdr != IPPROTO_TCP && 490 ip6h->nexthdr != IPPROTO_UDP) 491 return false; 492 493 if (ip6h->hop_limit <= 1) 494 return false; 495 496 thoff = sizeof(*ip6h); 497 if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ? 498 thoff + sizeof(struct tcphdr) : 499 thoff + sizeof(*ports))) 500 return false; 501 502 ip6h = ipv6_hdr(skb); 503 if (ip6h->nexthdr == IPPROTO_TCP) 504 *tcph = (void *)(skb_network_header(skb) + thoff); 505 506 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 507 tuple->src_v6 = ip6h->saddr; 508 tuple->dst_v6 = ip6h->daddr; 509 tuple->src_port = ports->source; 510 tuple->dst_port = ports->dest; 511 tuple->l3proto = AF_INET6; 512 tuple->l4proto = ip6h->nexthdr; 513 514 return true; 515 } 516 517 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p, 518 struct sk_buff *skb, 519 u8 family) 520 { 521 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft; 522 struct flow_offload_tuple_rhash *tuplehash; 523 struct flow_offload_tuple tuple = {}; 524 enum ip_conntrack_info ctinfo; 525 struct tcphdr *tcph = NULL; 526 struct flow_offload *flow; 527 struct nf_conn *ct; 528 u8 dir; 529 530 switch (family) { 531 case NFPROTO_IPV4: 532 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph)) 533 return false; 534 break; 535 case NFPROTO_IPV6: 536 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph)) 537 return false; 538 break; 539 default: 540 return false; 541 } 542 543 tuplehash = flow_offload_lookup(nf_ft, &tuple); 544 if (!tuplehash) 545 return false; 546 547 dir = tuplehash->tuple.dir; 548 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]); 549 ct = flow->ct; 550 551 if (tcph && (unlikely(tcph->fin || tcph->rst))) { 552 flow_offload_teardown(flow); 553 return false; 554 } 555 556 ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED : 557 IP_CT_ESTABLISHED_REPLY; 558 559 flow_offload_refresh(nf_ft, flow); 560 nf_conntrack_get(&ct->ct_general); 561 nf_ct_set(skb, ct, ctinfo); 562 if (nf_ft->flags & NF_FLOWTABLE_COUNTER) 563 nf_ct_acct_update(ct, dir, skb->len); 564 565 return true; 566 } 567 568 static int tcf_ct_flow_tables_init(void) 569 { 570 return rhashtable_init(&zones_ht, &zones_params); 571 } 572 573 static void tcf_ct_flow_tables_uninit(void) 574 { 575 rhashtable_destroy(&zones_ht); 576 } 577 578 static struct tc_action_ops act_ct_ops; 579 static unsigned int ct_net_id; 580 581 struct tc_ct_action_net { 582 struct tc_action_net tn; /* Must be first */ 583 bool labels; 584 }; 585 586 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ 587 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb, 588 u16 zone_id, bool force) 589 { 590 enum ip_conntrack_info ctinfo; 591 struct nf_conn *ct; 592 593 ct = nf_ct_get(skb, &ctinfo); 594 if (!ct) 595 return false; 596 if (!net_eq(net, read_pnet(&ct->ct_net))) 597 return false; 598 if (nf_ct_zone(ct)->id != zone_id) 599 return false; 600 601 /* Force conntrack entry direction. */ 602 if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 603 if (nf_ct_is_confirmed(ct)) 604 nf_ct_kill(ct); 605 606 nf_ct_put(ct); 607 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 608 609 return false; 610 } 611 612 return true; 613 } 614 615 /* Trim the skb to the length specified by the IP/IPv6 header, 616 * removing any trailing lower-layer padding. This prepares the skb 617 * for higher-layer processing that assumes skb->len excludes padding 618 * (such as nf_ip_checksum). The caller needs to pull the skb to the 619 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 620 */ 621 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family) 622 { 623 unsigned int len; 624 int err; 625 626 switch (family) { 627 case NFPROTO_IPV4: 628 len = ntohs(ip_hdr(skb)->tot_len); 629 break; 630 case NFPROTO_IPV6: 631 len = sizeof(struct ipv6hdr) 632 + ntohs(ipv6_hdr(skb)->payload_len); 633 break; 634 default: 635 len = skb->len; 636 } 637 638 err = pskb_trim_rcsum(skb, len); 639 640 return err; 641 } 642 643 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb) 644 { 645 u8 family = NFPROTO_UNSPEC; 646 647 switch (skb_protocol(skb, true)) { 648 case htons(ETH_P_IP): 649 family = NFPROTO_IPV4; 650 break; 651 case htons(ETH_P_IPV6): 652 family = NFPROTO_IPV6; 653 break; 654 default: 655 break; 656 } 657 658 return family; 659 } 660 661 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag) 662 { 663 unsigned int len; 664 665 len = skb_network_offset(skb) + sizeof(struct iphdr); 666 if (unlikely(skb->len < len)) 667 return -EINVAL; 668 if (unlikely(!pskb_may_pull(skb, len))) 669 return -ENOMEM; 670 671 *frag = ip_is_fragment(ip_hdr(skb)); 672 return 0; 673 } 674 675 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag) 676 { 677 unsigned int flags = 0, len, payload_ofs = 0; 678 unsigned short frag_off; 679 int nexthdr; 680 681 len = skb_network_offset(skb) + sizeof(struct ipv6hdr); 682 if (unlikely(skb->len < len)) 683 return -EINVAL; 684 if (unlikely(!pskb_may_pull(skb, len))) 685 return -ENOMEM; 686 687 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags); 688 if (unlikely(nexthdr < 0)) 689 return -EPROTO; 690 691 *frag = flags & IP6_FH_F_FRAG; 692 return 0; 693 } 694 695 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 696 u8 family, u16 zone, bool *defrag) 697 { 698 enum ip_conntrack_info ctinfo; 699 struct nf_conn *ct; 700 int err = 0; 701 bool frag; 702 u16 mru; 703 704 /* Previously seen (loopback)? Ignore. */ 705 ct = nf_ct_get(skb, &ctinfo); 706 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED) 707 return 0; 708 709 if (family == NFPROTO_IPV4) 710 err = tcf_ct_ipv4_is_fragment(skb, &frag); 711 else 712 err = tcf_ct_ipv6_is_fragment(skb, &frag); 713 if (err || !frag) 714 return err; 715 716 skb_get(skb); 717 mru = tc_skb_cb(skb)->mru; 718 719 if (family == NFPROTO_IPV4) { 720 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; 721 722 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 723 local_bh_disable(); 724 err = ip_defrag(net, skb, user); 725 local_bh_enable(); 726 if (err && err != -EINPROGRESS) 727 return err; 728 729 if (!err) { 730 *defrag = true; 731 mru = IPCB(skb)->frag_max_size; 732 } 733 } else { /* NFPROTO_IPV6 */ 734 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 735 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; 736 737 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); 738 err = nf_ct_frag6_gather(net, skb, user); 739 if (err && err != -EINPROGRESS) 740 goto out_free; 741 742 if (!err) { 743 *defrag = true; 744 mru = IP6CB(skb)->frag_max_size; 745 } 746 #else 747 err = -EOPNOTSUPP; 748 goto out_free; 749 #endif 750 } 751 752 if (err != -EINPROGRESS) 753 tc_skb_cb(skb)->mru = mru; 754 skb_clear_hash(skb); 755 skb->ignore_df = 1; 756 return err; 757 758 out_free: 759 kfree_skb(skb); 760 return err; 761 } 762 763 static void tcf_ct_params_free(struct rcu_head *head) 764 { 765 struct tcf_ct_params *params = container_of(head, 766 struct tcf_ct_params, rcu); 767 768 tcf_ct_flow_table_put(params); 769 770 if (params->tmpl) 771 nf_ct_put(params->tmpl); 772 kfree(params); 773 } 774 775 #if IS_ENABLED(CONFIG_NF_NAT) 776 /* Modelled after nf_nat_ipv[46]_fn(). 777 * range is only used for new, uninitialized NAT state. 778 * Returns either NF_ACCEPT or NF_DROP. 779 */ 780 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, 781 enum ip_conntrack_info ctinfo, 782 const struct nf_nat_range2 *range, 783 enum nf_nat_manip_type maniptype) 784 { 785 __be16 proto = skb_protocol(skb, true); 786 int hooknum, err = NF_ACCEPT; 787 788 /* See HOOK2MANIP(). */ 789 if (maniptype == NF_NAT_MANIP_SRC) 790 hooknum = NF_INET_LOCAL_IN; /* Source NAT */ 791 else 792 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ 793 794 switch (ctinfo) { 795 case IP_CT_RELATED: 796 case IP_CT_RELATED_REPLY: 797 if (proto == htons(ETH_P_IP) && 798 ip_hdr(skb)->protocol == IPPROTO_ICMP) { 799 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, 800 hooknum)) 801 err = NF_DROP; 802 goto out; 803 } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) { 804 __be16 frag_off; 805 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 806 int hdrlen = ipv6_skip_exthdr(skb, 807 sizeof(struct ipv6hdr), 808 &nexthdr, &frag_off); 809 810 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { 811 if (!nf_nat_icmpv6_reply_translation(skb, ct, 812 ctinfo, 813 hooknum, 814 hdrlen)) 815 err = NF_DROP; 816 goto out; 817 } 818 } 819 /* Non-ICMP, fall thru to initialize if needed. */ 820 fallthrough; 821 case IP_CT_NEW: 822 /* Seen it before? This can happen for loopback, retrans, 823 * or local packets. 824 */ 825 if (!nf_nat_initialized(ct, maniptype)) { 826 /* Initialize according to the NAT action. */ 827 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) 828 /* Action is set up to establish a new 829 * mapping. 830 */ 831 ? nf_nat_setup_info(ct, range, maniptype) 832 : nf_nat_alloc_null_binding(ct, hooknum); 833 if (err != NF_ACCEPT) 834 goto out; 835 } 836 break; 837 838 case IP_CT_ESTABLISHED: 839 case IP_CT_ESTABLISHED_REPLY: 840 break; 841 842 default: 843 err = NF_DROP; 844 goto out; 845 } 846 847 err = nf_nat_packet(ct, ctinfo, hooknum, skb); 848 if (err == NF_ACCEPT) { 849 if (maniptype == NF_NAT_MANIP_SRC) 850 tc_skb_cb(skb)->post_ct_snat = 1; 851 if (maniptype == NF_NAT_MANIP_DST) 852 tc_skb_cb(skb)->post_ct_dnat = 1; 853 } 854 out: 855 return err; 856 } 857 #endif /* CONFIG_NF_NAT */ 858 859 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask) 860 { 861 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 862 u32 new_mark; 863 864 if (!mask) 865 return; 866 867 new_mark = mark | (ct->mark & ~(mask)); 868 if (ct->mark != new_mark) { 869 ct->mark = new_mark; 870 if (nf_ct_is_confirmed(ct)) 871 nf_conntrack_event_cache(IPCT_MARK, ct); 872 } 873 #endif 874 } 875 876 static void tcf_ct_act_set_labels(struct nf_conn *ct, 877 u32 *labels, 878 u32 *labels_m) 879 { 880 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) 881 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels); 882 883 if (!memchr_inv(labels_m, 0, labels_sz)) 884 return; 885 886 nf_connlabels_replace(ct, labels, labels_m, 4); 887 #endif 888 } 889 890 static int tcf_ct_act_nat(struct sk_buff *skb, 891 struct nf_conn *ct, 892 enum ip_conntrack_info ctinfo, 893 int ct_action, 894 struct nf_nat_range2 *range, 895 bool commit) 896 { 897 #if IS_ENABLED(CONFIG_NF_NAT) 898 int err; 899 enum nf_nat_manip_type maniptype; 900 901 if (!(ct_action & TCA_CT_ACT_NAT)) 902 return NF_ACCEPT; 903 904 /* Add NAT extension if not confirmed yet. */ 905 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) 906 return NF_DROP; /* Can't NAT. */ 907 908 if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) && 909 (ctinfo != IP_CT_RELATED || commit)) { 910 /* NAT an established or related connection like before. */ 911 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) 912 /* This is the REPLY direction for a connection 913 * for which NAT was applied in the forward 914 * direction. Do the reverse NAT. 915 */ 916 maniptype = ct->status & IPS_SRC_NAT 917 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; 918 else 919 maniptype = ct->status & IPS_SRC_NAT 920 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; 921 } else if (ct_action & TCA_CT_ACT_NAT_SRC) { 922 maniptype = NF_NAT_MANIP_SRC; 923 } else if (ct_action & TCA_CT_ACT_NAT_DST) { 924 maniptype = NF_NAT_MANIP_DST; 925 } else { 926 return NF_ACCEPT; 927 } 928 929 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype); 930 if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) { 931 if (ct->status & IPS_SRC_NAT) { 932 if (maniptype == NF_NAT_MANIP_SRC) 933 maniptype = NF_NAT_MANIP_DST; 934 else 935 maniptype = NF_NAT_MANIP_SRC; 936 937 err = ct_nat_execute(skb, ct, ctinfo, range, 938 maniptype); 939 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) { 940 err = ct_nat_execute(skb, ct, ctinfo, NULL, 941 NF_NAT_MANIP_SRC); 942 } 943 } 944 return err; 945 #else 946 return NF_ACCEPT; 947 #endif 948 } 949 950 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 951 struct tcf_result *res) 952 { 953 struct net *net = dev_net(skb->dev); 954 bool cached, commit, clear, force; 955 enum ip_conntrack_info ctinfo; 956 struct tcf_ct *c = to_ct(a); 957 struct nf_conn *tmpl = NULL; 958 struct nf_hook_state state; 959 int nh_ofs, err, retval; 960 struct tcf_ct_params *p; 961 bool skip_add = false; 962 bool defrag = false; 963 struct nf_conn *ct; 964 u8 family; 965 966 p = rcu_dereference_bh(c->params); 967 968 retval = READ_ONCE(c->tcf_action); 969 commit = p->ct_action & TCA_CT_ACT_COMMIT; 970 clear = p->ct_action & TCA_CT_ACT_CLEAR; 971 force = p->ct_action & TCA_CT_ACT_FORCE; 972 tmpl = p->tmpl; 973 974 tcf_lastuse_update(&c->tcf_tm); 975 tcf_action_update_bstats(&c->common, skb); 976 977 if (clear) { 978 tc_skb_cb(skb)->post_ct = false; 979 ct = nf_ct_get(skb, &ctinfo); 980 if (ct) { 981 nf_ct_put(ct); 982 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 983 } 984 985 goto out_clear; 986 } 987 988 family = tcf_ct_skb_nf_family(skb); 989 if (family == NFPROTO_UNSPEC) 990 goto drop; 991 992 /* The conntrack module expects to be working at L3. 993 * We also try to pull the IPv4/6 header to linear area 994 */ 995 nh_ofs = skb_network_offset(skb); 996 skb_pull_rcsum(skb, nh_ofs); 997 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag); 998 if (err == -EINPROGRESS) { 999 retval = TC_ACT_STOLEN; 1000 goto out_clear; 1001 } 1002 if (err) 1003 goto drop; 1004 1005 err = tcf_ct_skb_network_trim(skb, family); 1006 if (err) 1007 goto drop; 1008 1009 /* If we are recirculating packets to match on ct fields and 1010 * committing with a separate ct action, then we don't need to 1011 * actually run the packet through conntrack twice unless it's for a 1012 * different zone. 1013 */ 1014 cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force); 1015 if (!cached) { 1016 if (tcf_ct_flow_table_lookup(p, skb, family)) { 1017 skip_add = true; 1018 goto do_nat; 1019 } 1020 1021 /* Associate skb with specified zone. */ 1022 if (tmpl) { 1023 nf_conntrack_put(skb_nfct(skb)); 1024 nf_conntrack_get(&tmpl->ct_general); 1025 nf_ct_set(skb, tmpl, IP_CT_NEW); 1026 } 1027 1028 state.hook = NF_INET_PRE_ROUTING; 1029 state.net = net; 1030 state.pf = family; 1031 err = nf_conntrack_in(skb, &state); 1032 if (err != NF_ACCEPT) 1033 goto out_push; 1034 } 1035 1036 do_nat: 1037 ct = nf_ct_get(skb, &ctinfo); 1038 if (!ct) 1039 goto out_push; 1040 nf_ct_deliver_cached_events(ct); 1041 nf_conn_act_ct_ext_fill(skb, ct, ctinfo); 1042 1043 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit); 1044 if (err != NF_ACCEPT) 1045 goto drop; 1046 1047 if (commit) { 1048 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask); 1049 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask); 1050 1051 if (!nf_ct_is_confirmed(ct)) 1052 nf_conn_act_ct_ext_add(ct); 1053 1054 /* This will take care of sending queued events 1055 * even if the connection is already confirmed. 1056 */ 1057 if (nf_conntrack_confirm(skb) != NF_ACCEPT) 1058 goto drop; 1059 } 1060 1061 if (!skip_add) 1062 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo); 1063 1064 out_push: 1065 skb_push_rcsum(skb, nh_ofs); 1066 1067 tc_skb_cb(skb)->post_ct = true; 1068 tc_skb_cb(skb)->zone = p->zone; 1069 out_clear: 1070 if (defrag) 1071 qdisc_skb_cb(skb)->pkt_len = skb->len; 1072 return retval; 1073 1074 drop: 1075 tcf_action_inc_drop_qstats(&c->common); 1076 return TC_ACT_SHOT; 1077 } 1078 1079 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = { 1080 [TCA_CT_ACTION] = { .type = NLA_U16 }, 1081 [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)), 1082 [TCA_CT_ZONE] = { .type = NLA_U16 }, 1083 [TCA_CT_MARK] = { .type = NLA_U32 }, 1084 [TCA_CT_MARK_MASK] = { .type = NLA_U32 }, 1085 [TCA_CT_LABELS] = { .type = NLA_BINARY, 1086 .len = 128 / BITS_PER_BYTE }, 1087 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY, 1088 .len = 128 / BITS_PER_BYTE }, 1089 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 }, 1090 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 }, 1091 [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1092 [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1093 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 }, 1094 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 }, 1095 }; 1096 1097 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p, 1098 struct tc_ct *parm, 1099 struct nlattr **tb, 1100 struct netlink_ext_ack *extack) 1101 { 1102 struct nf_nat_range2 *range; 1103 1104 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1105 return 0; 1106 1107 if (!IS_ENABLED(CONFIG_NF_NAT)) { 1108 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel"); 1109 return -EOPNOTSUPP; 1110 } 1111 1112 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1113 return 0; 1114 1115 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) && 1116 (p->ct_action & TCA_CT_ACT_NAT_DST)) { 1117 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time"); 1118 return -EOPNOTSUPP; 1119 } 1120 1121 range = &p->range; 1122 if (tb[TCA_CT_NAT_IPV4_MIN]) { 1123 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX]; 1124 1125 p->ipv4_range = true; 1126 range->flags |= NF_NAT_RANGE_MAP_IPS; 1127 range->min_addr.ip = 1128 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]); 1129 1130 range->max_addr.ip = max_attr ? 1131 nla_get_in_addr(max_attr) : 1132 range->min_addr.ip; 1133 } else if (tb[TCA_CT_NAT_IPV6_MIN]) { 1134 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX]; 1135 1136 p->ipv4_range = false; 1137 range->flags |= NF_NAT_RANGE_MAP_IPS; 1138 range->min_addr.in6 = 1139 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]); 1140 1141 range->max_addr.in6 = max_attr ? 1142 nla_get_in6_addr(max_attr) : 1143 range->min_addr.in6; 1144 } 1145 1146 if (tb[TCA_CT_NAT_PORT_MIN]) { 1147 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1148 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]); 1149 1150 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ? 1151 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) : 1152 range->min_proto.all; 1153 } 1154 1155 return 0; 1156 } 1157 1158 static void tcf_ct_set_key_val(struct nlattr **tb, 1159 void *val, int val_type, 1160 void *mask, int mask_type, 1161 int len) 1162 { 1163 if (!tb[val_type]) 1164 return; 1165 nla_memcpy(val, tb[val_type], len); 1166 1167 if (!mask) 1168 return; 1169 1170 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type]) 1171 memset(mask, 0xff, len); 1172 else 1173 nla_memcpy(mask, tb[mask_type], len); 1174 } 1175 1176 static int tcf_ct_fill_params(struct net *net, 1177 struct tcf_ct_params *p, 1178 struct tc_ct *parm, 1179 struct nlattr **tb, 1180 struct netlink_ext_ack *extack) 1181 { 1182 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1183 struct nf_conntrack_zone zone; 1184 struct nf_conn *tmpl; 1185 int err; 1186 1187 p->zone = NF_CT_DEFAULT_ZONE_ID; 1188 1189 tcf_ct_set_key_val(tb, 1190 &p->ct_action, TCA_CT_ACTION, 1191 NULL, TCA_CT_UNSPEC, 1192 sizeof(p->ct_action)); 1193 1194 if (p->ct_action & TCA_CT_ACT_CLEAR) 1195 return 0; 1196 1197 err = tcf_ct_fill_params_nat(p, parm, tb, extack); 1198 if (err) 1199 return err; 1200 1201 if (tb[TCA_CT_MARK]) { 1202 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) { 1203 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled."); 1204 return -EOPNOTSUPP; 1205 } 1206 tcf_ct_set_key_val(tb, 1207 &p->mark, TCA_CT_MARK, 1208 &p->mark_mask, TCA_CT_MARK_MASK, 1209 sizeof(p->mark)); 1210 } 1211 1212 if (tb[TCA_CT_LABELS]) { 1213 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) { 1214 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled."); 1215 return -EOPNOTSUPP; 1216 } 1217 1218 if (!tn->labels) { 1219 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length"); 1220 return -EOPNOTSUPP; 1221 } 1222 tcf_ct_set_key_val(tb, 1223 p->labels, TCA_CT_LABELS, 1224 p->labels_mask, TCA_CT_LABELS_MASK, 1225 sizeof(p->labels)); 1226 } 1227 1228 if (tb[TCA_CT_ZONE]) { 1229 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) { 1230 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled."); 1231 return -EOPNOTSUPP; 1232 } 1233 1234 tcf_ct_set_key_val(tb, 1235 &p->zone, TCA_CT_ZONE, 1236 NULL, TCA_CT_UNSPEC, 1237 sizeof(p->zone)); 1238 } 1239 1240 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0); 1241 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL); 1242 if (!tmpl) { 1243 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template"); 1244 return -ENOMEM; 1245 } 1246 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status); 1247 p->tmpl = tmpl; 1248 1249 return 0; 1250 } 1251 1252 static int tcf_ct_init(struct net *net, struct nlattr *nla, 1253 struct nlattr *est, struct tc_action **a, 1254 struct tcf_proto *tp, u32 flags, 1255 struct netlink_ext_ack *extack) 1256 { 1257 struct tc_action_net *tn = net_generic(net, ct_net_id); 1258 bool bind = flags & TCA_ACT_FLAGS_BIND; 1259 struct tcf_ct_params *params = NULL; 1260 struct nlattr *tb[TCA_CT_MAX + 1]; 1261 struct tcf_chain *goto_ch = NULL; 1262 struct tc_ct *parm; 1263 struct tcf_ct *c; 1264 int err, res = 0; 1265 u32 index; 1266 1267 if (!nla) { 1268 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed"); 1269 return -EINVAL; 1270 } 1271 1272 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack); 1273 if (err < 0) 1274 return err; 1275 1276 if (!tb[TCA_CT_PARMS]) { 1277 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters"); 1278 return -EINVAL; 1279 } 1280 parm = nla_data(tb[TCA_CT_PARMS]); 1281 index = parm->index; 1282 err = tcf_idr_check_alloc(tn, &index, a, bind); 1283 if (err < 0) 1284 return err; 1285 1286 if (!err) { 1287 err = tcf_idr_create_from_flags(tn, index, est, a, 1288 &act_ct_ops, bind, flags); 1289 if (err) { 1290 tcf_idr_cleanup(tn, index); 1291 return err; 1292 } 1293 res = ACT_P_CREATED; 1294 } else { 1295 if (bind) 1296 return 0; 1297 1298 if (!(flags & TCA_ACT_FLAGS_REPLACE)) { 1299 tcf_idr_release(*a, bind); 1300 return -EEXIST; 1301 } 1302 } 1303 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 1304 if (err < 0) 1305 goto cleanup; 1306 1307 c = to_ct(*a); 1308 1309 params = kzalloc(sizeof(*params), GFP_KERNEL); 1310 if (unlikely(!params)) { 1311 err = -ENOMEM; 1312 goto cleanup; 1313 } 1314 1315 err = tcf_ct_fill_params(net, params, parm, tb, extack); 1316 if (err) 1317 goto cleanup; 1318 1319 err = tcf_ct_flow_table_get(params); 1320 if (err) 1321 goto cleanup; 1322 1323 spin_lock_bh(&c->tcf_lock); 1324 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 1325 params = rcu_replace_pointer(c->params, params, 1326 lockdep_is_held(&c->tcf_lock)); 1327 spin_unlock_bh(&c->tcf_lock); 1328 1329 if (goto_ch) 1330 tcf_chain_put_by_act(goto_ch); 1331 if (params) 1332 call_rcu(¶ms->rcu, tcf_ct_params_free); 1333 1334 return res; 1335 1336 cleanup: 1337 if (goto_ch) 1338 tcf_chain_put_by_act(goto_ch); 1339 kfree(params); 1340 tcf_idr_release(*a, bind); 1341 return err; 1342 } 1343 1344 static void tcf_ct_cleanup(struct tc_action *a) 1345 { 1346 struct tcf_ct_params *params; 1347 struct tcf_ct *c = to_ct(a); 1348 1349 params = rcu_dereference_protected(c->params, 1); 1350 if (params) 1351 call_rcu(¶ms->rcu, tcf_ct_params_free); 1352 } 1353 1354 static int tcf_ct_dump_key_val(struct sk_buff *skb, 1355 void *val, int val_type, 1356 void *mask, int mask_type, 1357 int len) 1358 { 1359 int err; 1360 1361 if (mask && !memchr_inv(mask, 0, len)) 1362 return 0; 1363 1364 err = nla_put(skb, val_type, len, val); 1365 if (err) 1366 return err; 1367 1368 if (mask_type != TCA_CT_UNSPEC) { 1369 err = nla_put(skb, mask_type, len, mask); 1370 if (err) 1371 return err; 1372 } 1373 1374 return 0; 1375 } 1376 1377 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p) 1378 { 1379 struct nf_nat_range2 *range = &p->range; 1380 1381 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1382 return 0; 1383 1384 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1385 return 0; 1386 1387 if (range->flags & NF_NAT_RANGE_MAP_IPS) { 1388 if (p->ipv4_range) { 1389 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN, 1390 range->min_addr.ip)) 1391 return -1; 1392 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX, 1393 range->max_addr.ip)) 1394 return -1; 1395 } else { 1396 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN, 1397 &range->min_addr.in6)) 1398 return -1; 1399 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX, 1400 &range->max_addr.in6)) 1401 return -1; 1402 } 1403 } 1404 1405 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) { 1406 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN, 1407 range->min_proto.all)) 1408 return -1; 1409 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX, 1410 range->max_proto.all)) 1411 return -1; 1412 } 1413 1414 return 0; 1415 } 1416 1417 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a, 1418 int bind, int ref) 1419 { 1420 unsigned char *b = skb_tail_pointer(skb); 1421 struct tcf_ct *c = to_ct(a); 1422 struct tcf_ct_params *p; 1423 1424 struct tc_ct opt = { 1425 .index = c->tcf_index, 1426 .refcnt = refcount_read(&c->tcf_refcnt) - ref, 1427 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind, 1428 }; 1429 struct tcf_t t; 1430 1431 spin_lock_bh(&c->tcf_lock); 1432 p = rcu_dereference_protected(c->params, 1433 lockdep_is_held(&c->tcf_lock)); 1434 opt.action = c->tcf_action; 1435 1436 if (tcf_ct_dump_key_val(skb, 1437 &p->ct_action, TCA_CT_ACTION, 1438 NULL, TCA_CT_UNSPEC, 1439 sizeof(p->ct_action))) 1440 goto nla_put_failure; 1441 1442 if (p->ct_action & TCA_CT_ACT_CLEAR) 1443 goto skip_dump; 1444 1445 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1446 tcf_ct_dump_key_val(skb, 1447 &p->mark, TCA_CT_MARK, 1448 &p->mark_mask, TCA_CT_MARK_MASK, 1449 sizeof(p->mark))) 1450 goto nla_put_failure; 1451 1452 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1453 tcf_ct_dump_key_val(skb, 1454 p->labels, TCA_CT_LABELS, 1455 p->labels_mask, TCA_CT_LABELS_MASK, 1456 sizeof(p->labels))) 1457 goto nla_put_failure; 1458 1459 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1460 tcf_ct_dump_key_val(skb, 1461 &p->zone, TCA_CT_ZONE, 1462 NULL, TCA_CT_UNSPEC, 1463 sizeof(p->zone))) 1464 goto nla_put_failure; 1465 1466 if (tcf_ct_dump_nat(skb, p)) 1467 goto nla_put_failure; 1468 1469 skip_dump: 1470 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt)) 1471 goto nla_put_failure; 1472 1473 tcf_tm_dump(&t, &c->tcf_tm); 1474 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD)) 1475 goto nla_put_failure; 1476 spin_unlock_bh(&c->tcf_lock); 1477 1478 return skb->len; 1479 nla_put_failure: 1480 spin_unlock_bh(&c->tcf_lock); 1481 nlmsg_trim(skb, b); 1482 return -1; 1483 } 1484 1485 static int tcf_ct_walker(struct net *net, struct sk_buff *skb, 1486 struct netlink_callback *cb, int type, 1487 const struct tc_action_ops *ops, 1488 struct netlink_ext_ack *extack) 1489 { 1490 struct tc_action_net *tn = net_generic(net, ct_net_id); 1491 1492 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 1493 } 1494 1495 static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index) 1496 { 1497 struct tc_action_net *tn = net_generic(net, ct_net_id); 1498 1499 return tcf_idr_search(tn, a, index); 1500 } 1501 1502 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets, 1503 u64 drops, u64 lastuse, bool hw) 1504 { 1505 struct tcf_ct *c = to_ct(a); 1506 1507 tcf_action_update_stats(a, bytes, packets, drops, hw); 1508 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse); 1509 } 1510 1511 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data, 1512 u32 *index_inc, bool bind) 1513 { 1514 if (bind) { 1515 struct flow_action_entry *entry = entry_data; 1516 1517 entry->id = FLOW_ACTION_CT; 1518 entry->ct.action = tcf_ct_action(act); 1519 entry->ct.zone = tcf_ct_zone(act); 1520 entry->ct.flow_table = tcf_ct_ft(act); 1521 *index_inc = 1; 1522 } else { 1523 struct flow_offload_action *fl_action = entry_data; 1524 1525 fl_action->id = FLOW_ACTION_CT; 1526 } 1527 1528 return 0; 1529 } 1530 1531 static struct tc_action_ops act_ct_ops = { 1532 .kind = "ct", 1533 .id = TCA_ID_CT, 1534 .owner = THIS_MODULE, 1535 .act = tcf_ct_act, 1536 .dump = tcf_ct_dump, 1537 .init = tcf_ct_init, 1538 .cleanup = tcf_ct_cleanup, 1539 .walk = tcf_ct_walker, 1540 .lookup = tcf_ct_search, 1541 .stats_update = tcf_stats_update, 1542 .offload_act_setup = tcf_ct_offload_act_setup, 1543 .size = sizeof(struct tcf_ct), 1544 }; 1545 1546 static __net_init int ct_init_net(struct net *net) 1547 { 1548 unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8; 1549 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1550 1551 if (nf_connlabels_get(net, n_bits - 1)) { 1552 tn->labels = false; 1553 pr_err("act_ct: Failed to set connlabels length"); 1554 } else { 1555 tn->labels = true; 1556 } 1557 1558 return tc_action_net_init(net, &tn->tn, &act_ct_ops); 1559 } 1560 1561 static void __net_exit ct_exit_net(struct list_head *net_list) 1562 { 1563 struct net *net; 1564 1565 rtnl_lock(); 1566 list_for_each_entry(net, net_list, exit_list) { 1567 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1568 1569 if (tn->labels) 1570 nf_connlabels_put(net); 1571 } 1572 rtnl_unlock(); 1573 1574 tc_action_net_exit(net_list, ct_net_id); 1575 } 1576 1577 static struct pernet_operations ct_net_ops = { 1578 .init = ct_init_net, 1579 .exit_batch = ct_exit_net, 1580 .id = &ct_net_id, 1581 .size = sizeof(struct tc_ct_action_net), 1582 }; 1583 1584 static int __init ct_init_module(void) 1585 { 1586 int err; 1587 1588 act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0); 1589 if (!act_ct_wq) 1590 return -ENOMEM; 1591 1592 err = tcf_ct_flow_tables_init(); 1593 if (err) 1594 goto err_tbl_init; 1595 1596 err = tcf_register_action(&act_ct_ops, &ct_net_ops); 1597 if (err) 1598 goto err_register; 1599 1600 static_branch_inc(&tcf_frag_xmit_count); 1601 1602 return 0; 1603 1604 err_register: 1605 tcf_ct_flow_tables_uninit(); 1606 err_tbl_init: 1607 destroy_workqueue(act_ct_wq); 1608 return err; 1609 } 1610 1611 static void __exit ct_cleanup_module(void) 1612 { 1613 static_branch_dec(&tcf_frag_xmit_count); 1614 tcf_unregister_action(&act_ct_ops, &ct_net_ops); 1615 tcf_ct_flow_tables_uninit(); 1616 destroy_workqueue(act_ct_wq); 1617 } 1618 1619 module_init(ct_init_module); 1620 module_exit(ct_cleanup_module); 1621 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>"); 1622 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>"); 1623 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>"); 1624 MODULE_DESCRIPTION("Connection tracking action"); 1625 MODULE_LICENSE("GPL v2"); 1626