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 nf_ct_ext_type act_ct_extend __read_mostly = { 61 .len = sizeof(struct nf_conn_act_ct_ext), 62 .align = __alignof__(struct nf_conn_act_ct_ext), 63 .id = NF_CT_EXT_ACT_CT, 64 }; 65 66 static struct flow_action_entry * 67 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action) 68 { 69 int i = flow_action->num_entries++; 70 71 return &flow_action->entries[i]; 72 } 73 74 static void tcf_ct_add_mangle_action(struct flow_action *action, 75 enum flow_action_mangle_base htype, 76 u32 offset, 77 u32 mask, 78 u32 val) 79 { 80 struct flow_action_entry *entry; 81 82 entry = tcf_ct_flow_table_flow_action_get_next(action); 83 entry->id = FLOW_ACTION_MANGLE; 84 entry->mangle.htype = htype; 85 entry->mangle.mask = ~mask; 86 entry->mangle.offset = offset; 87 entry->mangle.val = val; 88 } 89 90 /* The following nat helper functions check if the inverted reverse tuple 91 * (target) is different then the current dir tuple - meaning nat for ports 92 * and/or ip is needed, and add the relevant mangle actions. 93 */ 94 static void 95 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple, 96 struct nf_conntrack_tuple target, 97 struct flow_action *action) 98 { 99 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) 100 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, 101 offsetof(struct iphdr, saddr), 102 0xFFFFFFFF, 103 be32_to_cpu(target.src.u3.ip)); 104 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) 105 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, 106 offsetof(struct iphdr, daddr), 107 0xFFFFFFFF, 108 be32_to_cpu(target.dst.u3.ip)); 109 } 110 111 static void 112 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action, 113 union nf_inet_addr *addr, 114 u32 offset) 115 { 116 int i; 117 118 for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++) 119 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6, 120 i * sizeof(u32) + offset, 121 0xFFFFFFFF, be32_to_cpu(addr->ip6[i])); 122 } 123 124 static void 125 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple, 126 struct nf_conntrack_tuple target, 127 struct flow_action *action) 128 { 129 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) 130 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3, 131 offsetof(struct ipv6hdr, 132 saddr)); 133 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) 134 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3, 135 offsetof(struct ipv6hdr, 136 daddr)); 137 } 138 139 static void 140 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple, 141 struct nf_conntrack_tuple target, 142 struct flow_action *action) 143 { 144 __be16 target_src = target.src.u.tcp.port; 145 __be16 target_dst = target.dst.u.tcp.port; 146 147 if (target_src != tuple->src.u.tcp.port) 148 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, 149 offsetof(struct tcphdr, source), 150 0xFFFF, be16_to_cpu(target_src)); 151 if (target_dst != tuple->dst.u.tcp.port) 152 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, 153 offsetof(struct tcphdr, dest), 154 0xFFFF, be16_to_cpu(target_dst)); 155 } 156 157 static void 158 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple, 159 struct nf_conntrack_tuple target, 160 struct flow_action *action) 161 { 162 __be16 target_src = target.src.u.udp.port; 163 __be16 target_dst = target.dst.u.udp.port; 164 165 if (target_src != tuple->src.u.udp.port) 166 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP, 167 offsetof(struct udphdr, source), 168 0xFFFF, be16_to_cpu(target_src)); 169 if (target_dst != tuple->dst.u.udp.port) 170 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP, 171 offsetof(struct udphdr, dest), 172 0xFFFF, be16_to_cpu(target_dst)); 173 } 174 175 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct, 176 enum ip_conntrack_dir dir, 177 struct flow_action *action) 178 { 179 struct nf_conn_labels *ct_labels; 180 struct flow_action_entry *entry; 181 enum ip_conntrack_info ctinfo; 182 u32 *act_ct_labels; 183 184 entry = tcf_ct_flow_table_flow_action_get_next(action); 185 entry->id = FLOW_ACTION_CT_METADATA; 186 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 187 entry->ct_metadata.mark = ct->mark; 188 #endif 189 ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED : 190 IP_CT_ESTABLISHED_REPLY; 191 /* aligns with the CT reference on the SKB nf_ct_set */ 192 entry->ct_metadata.cookie = (unsigned long)ct | ctinfo; 193 entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL; 194 195 act_ct_labels = entry->ct_metadata.labels; 196 ct_labels = nf_ct_labels_find(ct); 197 if (ct_labels) 198 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE); 199 else 200 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE); 201 } 202 203 static int tcf_ct_flow_table_add_action_nat(struct net *net, 204 struct nf_conn *ct, 205 enum ip_conntrack_dir dir, 206 struct flow_action *action) 207 { 208 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple; 209 struct nf_conntrack_tuple target; 210 211 if (!(ct->status & IPS_NAT_MASK)) 212 return 0; 213 214 nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); 215 216 switch (tuple->src.l3num) { 217 case NFPROTO_IPV4: 218 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target, 219 action); 220 break; 221 case NFPROTO_IPV6: 222 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target, 223 action); 224 break; 225 default: 226 return -EOPNOTSUPP; 227 } 228 229 switch (nf_ct_protonum(ct)) { 230 case IPPROTO_TCP: 231 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action); 232 break; 233 case IPPROTO_UDP: 234 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action); 235 break; 236 default: 237 return -EOPNOTSUPP; 238 } 239 240 return 0; 241 } 242 243 static int tcf_ct_flow_table_fill_actions(struct net *net, 244 const struct flow_offload *flow, 245 enum flow_offload_tuple_dir tdir, 246 struct nf_flow_rule *flow_rule) 247 { 248 struct flow_action *action = &flow_rule->rule->action; 249 int num_entries = action->num_entries; 250 struct nf_conn *ct = flow->ct; 251 enum ip_conntrack_dir dir; 252 int i, err; 253 254 switch (tdir) { 255 case FLOW_OFFLOAD_DIR_ORIGINAL: 256 dir = IP_CT_DIR_ORIGINAL; 257 break; 258 case FLOW_OFFLOAD_DIR_REPLY: 259 dir = IP_CT_DIR_REPLY; 260 break; 261 default: 262 return -EOPNOTSUPP; 263 } 264 265 err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action); 266 if (err) 267 goto err_nat; 268 269 tcf_ct_flow_table_add_action_meta(ct, dir, action); 270 return 0; 271 272 err_nat: 273 /* Clear filled actions */ 274 for (i = num_entries; i < action->num_entries; i++) 275 memset(&action->entries[i], 0, sizeof(action->entries[i])); 276 action->num_entries = num_entries; 277 278 return err; 279 } 280 281 static struct nf_flowtable_type flowtable_ct = { 282 .action = tcf_ct_flow_table_fill_actions, 283 .owner = THIS_MODULE, 284 }; 285 286 static int tcf_ct_flow_table_get(struct tcf_ct_params *params) 287 { 288 struct tcf_ct_flow_table *ct_ft; 289 int err = -ENOMEM; 290 291 mutex_lock(&zones_mutex); 292 ct_ft = rhashtable_lookup_fast(&zones_ht, ¶ms->zone, zones_params); 293 if (ct_ft && refcount_inc_not_zero(&ct_ft->ref)) 294 goto out_unlock; 295 296 ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL); 297 if (!ct_ft) 298 goto err_alloc; 299 refcount_set(&ct_ft->ref, 1); 300 301 ct_ft->zone = params->zone; 302 err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params); 303 if (err) 304 goto err_insert; 305 306 ct_ft->nf_ft.type = &flowtable_ct; 307 ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD | 308 NF_FLOWTABLE_COUNTER; 309 err = nf_flow_table_init(&ct_ft->nf_ft); 310 if (err) 311 goto err_init; 312 313 __module_get(THIS_MODULE); 314 out_unlock: 315 params->ct_ft = ct_ft; 316 params->nf_ft = &ct_ft->nf_ft; 317 mutex_unlock(&zones_mutex); 318 319 return 0; 320 321 err_init: 322 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 323 err_insert: 324 kfree(ct_ft); 325 err_alloc: 326 mutex_unlock(&zones_mutex); 327 return err; 328 } 329 330 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work) 331 { 332 struct flow_block_cb *block_cb, *tmp_cb; 333 struct tcf_ct_flow_table *ct_ft; 334 struct flow_block *block; 335 336 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table, 337 rwork); 338 nf_flow_table_free(&ct_ft->nf_ft); 339 340 /* Remove any remaining callbacks before cleanup */ 341 block = &ct_ft->nf_ft.flow_block; 342 down_write(&ct_ft->nf_ft.flow_block_lock); 343 list_for_each_entry_safe(block_cb, tmp_cb, &block->cb_list, list) { 344 list_del(&block_cb->list); 345 flow_block_cb_free(block_cb); 346 } 347 up_write(&ct_ft->nf_ft.flow_block_lock); 348 kfree(ct_ft); 349 350 module_put(THIS_MODULE); 351 } 352 353 static void tcf_ct_flow_table_put(struct tcf_ct_params *params) 354 { 355 struct tcf_ct_flow_table *ct_ft = params->ct_ft; 356 357 if (refcount_dec_and_test(¶ms->ct_ft->ref)) { 358 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 359 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work); 360 queue_rcu_work(act_ct_wq, &ct_ft->rwork); 361 } 362 } 363 364 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft, 365 struct nf_conn *ct, 366 bool tcp) 367 { 368 struct nf_conn_act_ct_ext *act_ct_ext; 369 struct flow_offload *entry; 370 int err; 371 372 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status)) 373 return; 374 375 entry = flow_offload_alloc(ct); 376 if (!entry) { 377 WARN_ON_ONCE(1); 378 goto err_alloc; 379 } 380 381 if (tcp) { 382 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 383 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 384 } 385 386 act_ct_ext = nf_conn_act_ct_ext_find(ct); 387 if (act_ct_ext) { 388 entry->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.iifidx = 389 act_ct_ext->ifindex[IP_CT_DIR_ORIGINAL]; 390 entry->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.iifidx = 391 act_ct_ext->ifindex[IP_CT_DIR_REPLY]; 392 } 393 394 err = flow_offload_add(&ct_ft->nf_ft, entry); 395 if (err) 396 goto err_add; 397 398 return; 399 400 err_add: 401 flow_offload_free(entry); 402 err_alloc: 403 clear_bit(IPS_OFFLOAD_BIT, &ct->status); 404 } 405 406 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft, 407 struct nf_conn *ct, 408 enum ip_conntrack_info ctinfo) 409 { 410 bool tcp = false; 411 412 if ((ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY) || 413 !test_bit(IPS_ASSURED_BIT, &ct->status)) 414 return; 415 416 switch (nf_ct_protonum(ct)) { 417 case IPPROTO_TCP: 418 tcp = true; 419 if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED) 420 return; 421 break; 422 case IPPROTO_UDP: 423 break; 424 default: 425 return; 426 } 427 428 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) || 429 ct->status & IPS_SEQ_ADJUST) 430 return; 431 432 tcf_ct_flow_table_add(ct_ft, ct, tcp); 433 } 434 435 static bool 436 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb, 437 struct flow_offload_tuple *tuple, 438 struct tcphdr **tcph) 439 { 440 struct flow_ports *ports; 441 unsigned int thoff; 442 struct iphdr *iph; 443 444 if (!pskb_network_may_pull(skb, sizeof(*iph))) 445 return false; 446 447 iph = ip_hdr(skb); 448 thoff = iph->ihl * 4; 449 450 if (ip_is_fragment(iph) || 451 unlikely(thoff != sizeof(struct iphdr))) 452 return false; 453 454 if (iph->protocol != IPPROTO_TCP && 455 iph->protocol != IPPROTO_UDP) 456 return false; 457 458 if (iph->ttl <= 1) 459 return false; 460 461 if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ? 462 thoff + sizeof(struct tcphdr) : 463 thoff + sizeof(*ports))) 464 return false; 465 466 iph = ip_hdr(skb); 467 if (iph->protocol == IPPROTO_TCP) 468 *tcph = (void *)(skb_network_header(skb) + thoff); 469 470 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 471 tuple->src_v4.s_addr = iph->saddr; 472 tuple->dst_v4.s_addr = iph->daddr; 473 tuple->src_port = ports->source; 474 tuple->dst_port = ports->dest; 475 tuple->l3proto = AF_INET; 476 tuple->l4proto = iph->protocol; 477 478 return true; 479 } 480 481 static bool 482 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb, 483 struct flow_offload_tuple *tuple, 484 struct tcphdr **tcph) 485 { 486 struct flow_ports *ports; 487 struct ipv6hdr *ip6h; 488 unsigned int thoff; 489 490 if (!pskb_network_may_pull(skb, sizeof(*ip6h))) 491 return false; 492 493 ip6h = ipv6_hdr(skb); 494 495 if (ip6h->nexthdr != IPPROTO_TCP && 496 ip6h->nexthdr != IPPROTO_UDP) 497 return false; 498 499 if (ip6h->hop_limit <= 1) 500 return false; 501 502 thoff = sizeof(*ip6h); 503 if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ? 504 thoff + sizeof(struct tcphdr) : 505 thoff + sizeof(*ports))) 506 return false; 507 508 ip6h = ipv6_hdr(skb); 509 if (ip6h->nexthdr == IPPROTO_TCP) 510 *tcph = (void *)(skb_network_header(skb) + thoff); 511 512 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 513 tuple->src_v6 = ip6h->saddr; 514 tuple->dst_v6 = ip6h->daddr; 515 tuple->src_port = ports->source; 516 tuple->dst_port = ports->dest; 517 tuple->l3proto = AF_INET6; 518 tuple->l4proto = ip6h->nexthdr; 519 520 return true; 521 } 522 523 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p, 524 struct sk_buff *skb, 525 u8 family) 526 { 527 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft; 528 struct flow_offload_tuple_rhash *tuplehash; 529 struct flow_offload_tuple tuple = {}; 530 enum ip_conntrack_info ctinfo; 531 struct tcphdr *tcph = NULL; 532 struct flow_offload *flow; 533 struct nf_conn *ct; 534 u8 dir; 535 536 switch (family) { 537 case NFPROTO_IPV4: 538 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph)) 539 return false; 540 break; 541 case NFPROTO_IPV6: 542 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph)) 543 return false; 544 break; 545 default: 546 return false; 547 } 548 549 tuplehash = flow_offload_lookup(nf_ft, &tuple); 550 if (!tuplehash) 551 return false; 552 553 dir = tuplehash->tuple.dir; 554 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]); 555 ct = flow->ct; 556 557 if (tcph && (unlikely(tcph->fin || tcph->rst))) { 558 flow_offload_teardown(flow); 559 return false; 560 } 561 562 ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED : 563 IP_CT_ESTABLISHED_REPLY; 564 565 flow_offload_refresh(nf_ft, flow); 566 nf_conntrack_get(&ct->ct_general); 567 nf_ct_set(skb, ct, ctinfo); 568 if (nf_ft->flags & NF_FLOWTABLE_COUNTER) 569 nf_ct_acct_update(ct, dir, skb->len); 570 571 return true; 572 } 573 574 static int tcf_ct_flow_tables_init(void) 575 { 576 return rhashtable_init(&zones_ht, &zones_params); 577 } 578 579 static void tcf_ct_flow_tables_uninit(void) 580 { 581 rhashtable_destroy(&zones_ht); 582 } 583 584 static struct tc_action_ops act_ct_ops; 585 static unsigned int ct_net_id; 586 587 struct tc_ct_action_net { 588 struct tc_action_net tn; /* Must be first */ 589 bool labels; 590 }; 591 592 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ 593 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb, 594 u16 zone_id, bool force) 595 { 596 enum ip_conntrack_info ctinfo; 597 struct nf_conn *ct; 598 599 ct = nf_ct_get(skb, &ctinfo); 600 if (!ct) 601 return false; 602 if (!net_eq(net, read_pnet(&ct->ct_net))) 603 return false; 604 if (nf_ct_zone(ct)->id != zone_id) 605 return false; 606 607 /* Force conntrack entry direction. */ 608 if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 609 if (nf_ct_is_confirmed(ct)) 610 nf_ct_kill(ct); 611 612 nf_ct_put(ct); 613 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 614 615 return false; 616 } 617 618 return true; 619 } 620 621 /* Trim the skb to the length specified by the IP/IPv6 header, 622 * removing any trailing lower-layer padding. This prepares the skb 623 * for higher-layer processing that assumes skb->len excludes padding 624 * (such as nf_ip_checksum). The caller needs to pull the skb to the 625 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 626 */ 627 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family) 628 { 629 unsigned int len; 630 int err; 631 632 switch (family) { 633 case NFPROTO_IPV4: 634 len = ntohs(ip_hdr(skb)->tot_len); 635 break; 636 case NFPROTO_IPV6: 637 len = sizeof(struct ipv6hdr) 638 + ntohs(ipv6_hdr(skb)->payload_len); 639 break; 640 default: 641 len = skb->len; 642 } 643 644 err = pskb_trim_rcsum(skb, len); 645 646 return err; 647 } 648 649 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb) 650 { 651 u8 family = NFPROTO_UNSPEC; 652 653 switch (skb_protocol(skb, true)) { 654 case htons(ETH_P_IP): 655 family = NFPROTO_IPV4; 656 break; 657 case htons(ETH_P_IPV6): 658 family = NFPROTO_IPV6; 659 break; 660 default: 661 break; 662 } 663 664 return family; 665 } 666 667 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag) 668 { 669 unsigned int len; 670 671 len = skb_network_offset(skb) + sizeof(struct iphdr); 672 if (unlikely(skb->len < len)) 673 return -EINVAL; 674 if (unlikely(!pskb_may_pull(skb, len))) 675 return -ENOMEM; 676 677 *frag = ip_is_fragment(ip_hdr(skb)); 678 return 0; 679 } 680 681 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag) 682 { 683 unsigned int flags = 0, len, payload_ofs = 0; 684 unsigned short frag_off; 685 int nexthdr; 686 687 len = skb_network_offset(skb) + sizeof(struct ipv6hdr); 688 if (unlikely(skb->len < len)) 689 return -EINVAL; 690 if (unlikely(!pskb_may_pull(skb, len))) 691 return -ENOMEM; 692 693 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags); 694 if (unlikely(nexthdr < 0)) 695 return -EPROTO; 696 697 *frag = flags & IP6_FH_F_FRAG; 698 return 0; 699 } 700 701 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 702 u8 family, u16 zone, bool *defrag) 703 { 704 enum ip_conntrack_info ctinfo; 705 struct nf_conn *ct; 706 int err = 0; 707 bool frag; 708 u16 mru; 709 710 /* Previously seen (loopback)? Ignore. */ 711 ct = nf_ct_get(skb, &ctinfo); 712 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED) 713 return 0; 714 715 if (family == NFPROTO_IPV4) 716 err = tcf_ct_ipv4_is_fragment(skb, &frag); 717 else 718 err = tcf_ct_ipv6_is_fragment(skb, &frag); 719 if (err || !frag) 720 return err; 721 722 skb_get(skb); 723 mru = tc_skb_cb(skb)->mru; 724 725 if (family == NFPROTO_IPV4) { 726 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; 727 728 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 729 local_bh_disable(); 730 err = ip_defrag(net, skb, user); 731 local_bh_enable(); 732 if (err && err != -EINPROGRESS) 733 return err; 734 735 if (!err) { 736 *defrag = true; 737 mru = IPCB(skb)->frag_max_size; 738 } 739 } else { /* NFPROTO_IPV6 */ 740 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 741 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; 742 743 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); 744 err = nf_ct_frag6_gather(net, skb, user); 745 if (err && err != -EINPROGRESS) 746 goto out_free; 747 748 if (!err) { 749 *defrag = true; 750 mru = IP6CB(skb)->frag_max_size; 751 } 752 #else 753 err = -EOPNOTSUPP; 754 goto out_free; 755 #endif 756 } 757 758 if (err != -EINPROGRESS) 759 tc_skb_cb(skb)->mru = mru; 760 skb_clear_hash(skb); 761 skb->ignore_df = 1; 762 return err; 763 764 out_free: 765 kfree_skb(skb); 766 return err; 767 } 768 769 static void tcf_ct_params_free(struct rcu_head *head) 770 { 771 struct tcf_ct_params *params = container_of(head, 772 struct tcf_ct_params, rcu); 773 774 tcf_ct_flow_table_put(params); 775 776 if (params->tmpl) 777 nf_ct_put(params->tmpl); 778 kfree(params); 779 } 780 781 #if IS_ENABLED(CONFIG_NF_NAT) 782 /* Modelled after nf_nat_ipv[46]_fn(). 783 * range is only used for new, uninitialized NAT state. 784 * Returns either NF_ACCEPT or NF_DROP. 785 */ 786 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, 787 enum ip_conntrack_info ctinfo, 788 const struct nf_nat_range2 *range, 789 enum nf_nat_manip_type maniptype) 790 { 791 __be16 proto = skb_protocol(skb, true); 792 int hooknum, err = NF_ACCEPT; 793 794 /* See HOOK2MANIP(). */ 795 if (maniptype == NF_NAT_MANIP_SRC) 796 hooknum = NF_INET_LOCAL_IN; /* Source NAT */ 797 else 798 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ 799 800 switch (ctinfo) { 801 case IP_CT_RELATED: 802 case IP_CT_RELATED_REPLY: 803 if (proto == htons(ETH_P_IP) && 804 ip_hdr(skb)->protocol == IPPROTO_ICMP) { 805 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, 806 hooknum)) 807 err = NF_DROP; 808 goto out; 809 } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) { 810 __be16 frag_off; 811 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 812 int hdrlen = ipv6_skip_exthdr(skb, 813 sizeof(struct ipv6hdr), 814 &nexthdr, &frag_off); 815 816 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { 817 if (!nf_nat_icmpv6_reply_translation(skb, ct, 818 ctinfo, 819 hooknum, 820 hdrlen)) 821 err = NF_DROP; 822 goto out; 823 } 824 } 825 /* Non-ICMP, fall thru to initialize if needed. */ 826 fallthrough; 827 case IP_CT_NEW: 828 /* Seen it before? This can happen for loopback, retrans, 829 * or local packets. 830 */ 831 if (!nf_nat_initialized(ct, maniptype)) { 832 /* Initialize according to the NAT action. */ 833 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) 834 /* Action is set up to establish a new 835 * mapping. 836 */ 837 ? nf_nat_setup_info(ct, range, maniptype) 838 : nf_nat_alloc_null_binding(ct, hooknum); 839 if (err != NF_ACCEPT) 840 goto out; 841 } 842 break; 843 844 case IP_CT_ESTABLISHED: 845 case IP_CT_ESTABLISHED_REPLY: 846 break; 847 848 default: 849 err = NF_DROP; 850 goto out; 851 } 852 853 err = nf_nat_packet(ct, ctinfo, hooknum, skb); 854 if (err == NF_ACCEPT) { 855 if (maniptype == NF_NAT_MANIP_SRC) 856 tc_skb_cb(skb)->post_ct_snat = 1; 857 if (maniptype == NF_NAT_MANIP_DST) 858 tc_skb_cb(skb)->post_ct_dnat = 1; 859 } 860 out: 861 return err; 862 } 863 #endif /* CONFIG_NF_NAT */ 864 865 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask) 866 { 867 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 868 u32 new_mark; 869 870 if (!mask) 871 return; 872 873 new_mark = mark | (ct->mark & ~(mask)); 874 if (ct->mark != new_mark) { 875 ct->mark = new_mark; 876 if (nf_ct_is_confirmed(ct)) 877 nf_conntrack_event_cache(IPCT_MARK, ct); 878 } 879 #endif 880 } 881 882 static void tcf_ct_act_set_labels(struct nf_conn *ct, 883 u32 *labels, 884 u32 *labels_m) 885 { 886 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) 887 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels); 888 889 if (!memchr_inv(labels_m, 0, labels_sz)) 890 return; 891 892 nf_connlabels_replace(ct, labels, labels_m, 4); 893 #endif 894 } 895 896 static int tcf_ct_act_nat(struct sk_buff *skb, 897 struct nf_conn *ct, 898 enum ip_conntrack_info ctinfo, 899 int ct_action, 900 struct nf_nat_range2 *range, 901 bool commit) 902 { 903 #if IS_ENABLED(CONFIG_NF_NAT) 904 int err; 905 enum nf_nat_manip_type maniptype; 906 907 if (!(ct_action & TCA_CT_ACT_NAT)) 908 return NF_ACCEPT; 909 910 /* Add NAT extension if not confirmed yet. */ 911 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) 912 return NF_DROP; /* Can't NAT. */ 913 914 if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) && 915 (ctinfo != IP_CT_RELATED || commit)) { 916 /* NAT an established or related connection like before. */ 917 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) 918 /* This is the REPLY direction for a connection 919 * for which NAT was applied in the forward 920 * direction. Do the reverse NAT. 921 */ 922 maniptype = ct->status & IPS_SRC_NAT 923 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; 924 else 925 maniptype = ct->status & IPS_SRC_NAT 926 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; 927 } else if (ct_action & TCA_CT_ACT_NAT_SRC) { 928 maniptype = NF_NAT_MANIP_SRC; 929 } else if (ct_action & TCA_CT_ACT_NAT_DST) { 930 maniptype = NF_NAT_MANIP_DST; 931 } else { 932 return NF_ACCEPT; 933 } 934 935 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype); 936 if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) { 937 if (ct->status & IPS_SRC_NAT) { 938 if (maniptype == NF_NAT_MANIP_SRC) 939 maniptype = NF_NAT_MANIP_DST; 940 else 941 maniptype = NF_NAT_MANIP_SRC; 942 943 err = ct_nat_execute(skb, ct, ctinfo, range, 944 maniptype); 945 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) { 946 err = ct_nat_execute(skb, ct, ctinfo, NULL, 947 NF_NAT_MANIP_SRC); 948 } 949 } 950 return err; 951 #else 952 return NF_ACCEPT; 953 #endif 954 } 955 956 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 957 struct tcf_result *res) 958 { 959 struct net *net = dev_net(skb->dev); 960 bool cached, commit, clear, force; 961 enum ip_conntrack_info ctinfo; 962 struct tcf_ct *c = to_ct(a); 963 struct nf_conn *tmpl = NULL; 964 struct nf_hook_state state; 965 int nh_ofs, err, retval; 966 struct tcf_ct_params *p; 967 bool skip_add = false; 968 bool defrag = false; 969 struct nf_conn *ct; 970 u8 family; 971 972 p = rcu_dereference_bh(c->params); 973 974 retval = READ_ONCE(c->tcf_action); 975 commit = p->ct_action & TCA_CT_ACT_COMMIT; 976 clear = p->ct_action & TCA_CT_ACT_CLEAR; 977 force = p->ct_action & TCA_CT_ACT_FORCE; 978 tmpl = p->tmpl; 979 980 tcf_lastuse_update(&c->tcf_tm); 981 tcf_action_update_bstats(&c->common, skb); 982 983 if (clear) { 984 tc_skb_cb(skb)->post_ct = false; 985 ct = nf_ct_get(skb, &ctinfo); 986 if (ct) { 987 nf_ct_put(ct); 988 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 989 } 990 991 goto out_clear; 992 } 993 994 family = tcf_ct_skb_nf_family(skb); 995 if (family == NFPROTO_UNSPEC) 996 goto drop; 997 998 /* The conntrack module expects to be working at L3. 999 * We also try to pull the IPv4/6 header to linear area 1000 */ 1001 nh_ofs = skb_network_offset(skb); 1002 skb_pull_rcsum(skb, nh_ofs); 1003 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag); 1004 if (err == -EINPROGRESS) { 1005 retval = TC_ACT_STOLEN; 1006 goto out_clear; 1007 } 1008 if (err) 1009 goto drop; 1010 1011 err = tcf_ct_skb_network_trim(skb, family); 1012 if (err) 1013 goto drop; 1014 1015 /* If we are recirculating packets to match on ct fields and 1016 * committing with a separate ct action, then we don't need to 1017 * actually run the packet through conntrack twice unless it's for a 1018 * different zone. 1019 */ 1020 cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force); 1021 if (!cached) { 1022 if (tcf_ct_flow_table_lookup(p, skb, family)) { 1023 skip_add = true; 1024 goto do_nat; 1025 } 1026 1027 /* Associate skb with specified zone. */ 1028 if (tmpl) { 1029 nf_conntrack_put(skb_nfct(skb)); 1030 nf_conntrack_get(&tmpl->ct_general); 1031 nf_ct_set(skb, tmpl, IP_CT_NEW); 1032 } 1033 1034 state.hook = NF_INET_PRE_ROUTING; 1035 state.net = net; 1036 state.pf = family; 1037 err = nf_conntrack_in(skb, &state); 1038 if (err != NF_ACCEPT) 1039 goto out_push; 1040 } 1041 1042 do_nat: 1043 ct = nf_ct_get(skb, &ctinfo); 1044 if (!ct) 1045 goto out_push; 1046 nf_ct_deliver_cached_events(ct); 1047 nf_conn_act_ct_ext_fill(skb, ct, ctinfo); 1048 1049 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit); 1050 if (err != NF_ACCEPT) 1051 goto drop; 1052 1053 if (commit) { 1054 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask); 1055 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask); 1056 1057 if (!nf_ct_is_confirmed(ct)) 1058 nf_conn_act_ct_ext_add(ct); 1059 1060 /* This will take care of sending queued events 1061 * even if the connection is already confirmed. 1062 */ 1063 if (nf_conntrack_confirm(skb) != NF_ACCEPT) 1064 goto drop; 1065 } 1066 1067 if (!skip_add) 1068 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo); 1069 1070 out_push: 1071 skb_push_rcsum(skb, nh_ofs); 1072 1073 tc_skb_cb(skb)->post_ct = true; 1074 tc_skb_cb(skb)->zone = p->zone; 1075 out_clear: 1076 if (defrag) 1077 qdisc_skb_cb(skb)->pkt_len = skb->len; 1078 return retval; 1079 1080 drop: 1081 tcf_action_inc_drop_qstats(&c->common); 1082 return TC_ACT_SHOT; 1083 } 1084 1085 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = { 1086 [TCA_CT_ACTION] = { .type = NLA_U16 }, 1087 [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)), 1088 [TCA_CT_ZONE] = { .type = NLA_U16 }, 1089 [TCA_CT_MARK] = { .type = NLA_U32 }, 1090 [TCA_CT_MARK_MASK] = { .type = NLA_U32 }, 1091 [TCA_CT_LABELS] = { .type = NLA_BINARY, 1092 .len = 128 / BITS_PER_BYTE }, 1093 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY, 1094 .len = 128 / BITS_PER_BYTE }, 1095 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 }, 1096 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 }, 1097 [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1098 [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1099 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 }, 1100 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 }, 1101 }; 1102 1103 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p, 1104 struct tc_ct *parm, 1105 struct nlattr **tb, 1106 struct netlink_ext_ack *extack) 1107 { 1108 struct nf_nat_range2 *range; 1109 1110 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1111 return 0; 1112 1113 if (!IS_ENABLED(CONFIG_NF_NAT)) { 1114 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel"); 1115 return -EOPNOTSUPP; 1116 } 1117 1118 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1119 return 0; 1120 1121 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) && 1122 (p->ct_action & TCA_CT_ACT_NAT_DST)) { 1123 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time"); 1124 return -EOPNOTSUPP; 1125 } 1126 1127 range = &p->range; 1128 if (tb[TCA_CT_NAT_IPV4_MIN]) { 1129 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX]; 1130 1131 p->ipv4_range = true; 1132 range->flags |= NF_NAT_RANGE_MAP_IPS; 1133 range->min_addr.ip = 1134 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]); 1135 1136 range->max_addr.ip = max_attr ? 1137 nla_get_in_addr(max_attr) : 1138 range->min_addr.ip; 1139 } else if (tb[TCA_CT_NAT_IPV6_MIN]) { 1140 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX]; 1141 1142 p->ipv4_range = false; 1143 range->flags |= NF_NAT_RANGE_MAP_IPS; 1144 range->min_addr.in6 = 1145 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]); 1146 1147 range->max_addr.in6 = max_attr ? 1148 nla_get_in6_addr(max_attr) : 1149 range->min_addr.in6; 1150 } 1151 1152 if (tb[TCA_CT_NAT_PORT_MIN]) { 1153 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1154 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]); 1155 1156 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ? 1157 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) : 1158 range->min_proto.all; 1159 } 1160 1161 return 0; 1162 } 1163 1164 static void tcf_ct_set_key_val(struct nlattr **tb, 1165 void *val, int val_type, 1166 void *mask, int mask_type, 1167 int len) 1168 { 1169 if (!tb[val_type]) 1170 return; 1171 nla_memcpy(val, tb[val_type], len); 1172 1173 if (!mask) 1174 return; 1175 1176 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type]) 1177 memset(mask, 0xff, len); 1178 else 1179 nla_memcpy(mask, tb[mask_type], len); 1180 } 1181 1182 static int tcf_ct_fill_params(struct net *net, 1183 struct tcf_ct_params *p, 1184 struct tc_ct *parm, 1185 struct nlattr **tb, 1186 struct netlink_ext_ack *extack) 1187 { 1188 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1189 struct nf_conntrack_zone zone; 1190 struct nf_conn *tmpl; 1191 int err; 1192 1193 p->zone = NF_CT_DEFAULT_ZONE_ID; 1194 1195 tcf_ct_set_key_val(tb, 1196 &p->ct_action, TCA_CT_ACTION, 1197 NULL, TCA_CT_UNSPEC, 1198 sizeof(p->ct_action)); 1199 1200 if (p->ct_action & TCA_CT_ACT_CLEAR) 1201 return 0; 1202 1203 err = tcf_ct_fill_params_nat(p, parm, tb, extack); 1204 if (err) 1205 return err; 1206 1207 if (tb[TCA_CT_MARK]) { 1208 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) { 1209 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled."); 1210 return -EOPNOTSUPP; 1211 } 1212 tcf_ct_set_key_val(tb, 1213 &p->mark, TCA_CT_MARK, 1214 &p->mark_mask, TCA_CT_MARK_MASK, 1215 sizeof(p->mark)); 1216 } 1217 1218 if (tb[TCA_CT_LABELS]) { 1219 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) { 1220 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled."); 1221 return -EOPNOTSUPP; 1222 } 1223 1224 if (!tn->labels) { 1225 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length"); 1226 return -EOPNOTSUPP; 1227 } 1228 tcf_ct_set_key_val(tb, 1229 p->labels, TCA_CT_LABELS, 1230 p->labels_mask, TCA_CT_LABELS_MASK, 1231 sizeof(p->labels)); 1232 } 1233 1234 if (tb[TCA_CT_ZONE]) { 1235 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) { 1236 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled."); 1237 return -EOPNOTSUPP; 1238 } 1239 1240 tcf_ct_set_key_val(tb, 1241 &p->zone, TCA_CT_ZONE, 1242 NULL, TCA_CT_UNSPEC, 1243 sizeof(p->zone)); 1244 } 1245 1246 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0); 1247 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL); 1248 if (!tmpl) { 1249 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template"); 1250 return -ENOMEM; 1251 } 1252 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status); 1253 p->tmpl = tmpl; 1254 1255 return 0; 1256 } 1257 1258 static int tcf_ct_init(struct net *net, struct nlattr *nla, 1259 struct nlattr *est, struct tc_action **a, 1260 struct tcf_proto *tp, u32 flags, 1261 struct netlink_ext_ack *extack) 1262 { 1263 struct tc_action_net *tn = net_generic(net, ct_net_id); 1264 bool bind = flags & TCA_ACT_FLAGS_BIND; 1265 struct tcf_ct_params *params = NULL; 1266 struct nlattr *tb[TCA_CT_MAX + 1]; 1267 struct tcf_chain *goto_ch = NULL; 1268 struct tc_ct *parm; 1269 struct tcf_ct *c; 1270 int err, res = 0; 1271 u32 index; 1272 1273 if (!nla) { 1274 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed"); 1275 return -EINVAL; 1276 } 1277 1278 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack); 1279 if (err < 0) 1280 return err; 1281 1282 if (!tb[TCA_CT_PARMS]) { 1283 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters"); 1284 return -EINVAL; 1285 } 1286 parm = nla_data(tb[TCA_CT_PARMS]); 1287 index = parm->index; 1288 err = tcf_idr_check_alloc(tn, &index, a, bind); 1289 if (err < 0) 1290 return err; 1291 1292 if (!err) { 1293 err = tcf_idr_create_from_flags(tn, index, est, a, 1294 &act_ct_ops, bind, flags); 1295 if (err) { 1296 tcf_idr_cleanup(tn, index); 1297 return err; 1298 } 1299 res = ACT_P_CREATED; 1300 } else { 1301 if (bind) 1302 return 0; 1303 1304 if (!(flags & TCA_ACT_FLAGS_REPLACE)) { 1305 tcf_idr_release(*a, bind); 1306 return -EEXIST; 1307 } 1308 } 1309 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 1310 if (err < 0) 1311 goto cleanup; 1312 1313 c = to_ct(*a); 1314 1315 params = kzalloc(sizeof(*params), GFP_KERNEL); 1316 if (unlikely(!params)) { 1317 err = -ENOMEM; 1318 goto cleanup; 1319 } 1320 1321 err = tcf_ct_fill_params(net, params, parm, tb, extack); 1322 if (err) 1323 goto cleanup; 1324 1325 err = tcf_ct_flow_table_get(params); 1326 if (err) 1327 goto cleanup; 1328 1329 spin_lock_bh(&c->tcf_lock); 1330 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 1331 params = rcu_replace_pointer(c->params, params, 1332 lockdep_is_held(&c->tcf_lock)); 1333 spin_unlock_bh(&c->tcf_lock); 1334 1335 if (goto_ch) 1336 tcf_chain_put_by_act(goto_ch); 1337 if (params) 1338 call_rcu(¶ms->rcu, tcf_ct_params_free); 1339 1340 return res; 1341 1342 cleanup: 1343 if (goto_ch) 1344 tcf_chain_put_by_act(goto_ch); 1345 kfree(params); 1346 tcf_idr_release(*a, bind); 1347 return err; 1348 } 1349 1350 static void tcf_ct_cleanup(struct tc_action *a) 1351 { 1352 struct tcf_ct_params *params; 1353 struct tcf_ct *c = to_ct(a); 1354 1355 params = rcu_dereference_protected(c->params, 1); 1356 if (params) 1357 call_rcu(¶ms->rcu, tcf_ct_params_free); 1358 } 1359 1360 static int tcf_ct_dump_key_val(struct sk_buff *skb, 1361 void *val, int val_type, 1362 void *mask, int mask_type, 1363 int len) 1364 { 1365 int err; 1366 1367 if (mask && !memchr_inv(mask, 0, len)) 1368 return 0; 1369 1370 err = nla_put(skb, val_type, len, val); 1371 if (err) 1372 return err; 1373 1374 if (mask_type != TCA_CT_UNSPEC) { 1375 err = nla_put(skb, mask_type, len, mask); 1376 if (err) 1377 return err; 1378 } 1379 1380 return 0; 1381 } 1382 1383 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p) 1384 { 1385 struct nf_nat_range2 *range = &p->range; 1386 1387 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1388 return 0; 1389 1390 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1391 return 0; 1392 1393 if (range->flags & NF_NAT_RANGE_MAP_IPS) { 1394 if (p->ipv4_range) { 1395 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN, 1396 range->min_addr.ip)) 1397 return -1; 1398 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX, 1399 range->max_addr.ip)) 1400 return -1; 1401 } else { 1402 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN, 1403 &range->min_addr.in6)) 1404 return -1; 1405 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX, 1406 &range->max_addr.in6)) 1407 return -1; 1408 } 1409 } 1410 1411 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) { 1412 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN, 1413 range->min_proto.all)) 1414 return -1; 1415 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX, 1416 range->max_proto.all)) 1417 return -1; 1418 } 1419 1420 return 0; 1421 } 1422 1423 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a, 1424 int bind, int ref) 1425 { 1426 unsigned char *b = skb_tail_pointer(skb); 1427 struct tcf_ct *c = to_ct(a); 1428 struct tcf_ct_params *p; 1429 1430 struct tc_ct opt = { 1431 .index = c->tcf_index, 1432 .refcnt = refcount_read(&c->tcf_refcnt) - ref, 1433 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind, 1434 }; 1435 struct tcf_t t; 1436 1437 spin_lock_bh(&c->tcf_lock); 1438 p = rcu_dereference_protected(c->params, 1439 lockdep_is_held(&c->tcf_lock)); 1440 opt.action = c->tcf_action; 1441 1442 if (tcf_ct_dump_key_val(skb, 1443 &p->ct_action, TCA_CT_ACTION, 1444 NULL, TCA_CT_UNSPEC, 1445 sizeof(p->ct_action))) 1446 goto nla_put_failure; 1447 1448 if (p->ct_action & TCA_CT_ACT_CLEAR) 1449 goto skip_dump; 1450 1451 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1452 tcf_ct_dump_key_val(skb, 1453 &p->mark, TCA_CT_MARK, 1454 &p->mark_mask, TCA_CT_MARK_MASK, 1455 sizeof(p->mark))) 1456 goto nla_put_failure; 1457 1458 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1459 tcf_ct_dump_key_val(skb, 1460 p->labels, TCA_CT_LABELS, 1461 p->labels_mask, TCA_CT_LABELS_MASK, 1462 sizeof(p->labels))) 1463 goto nla_put_failure; 1464 1465 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1466 tcf_ct_dump_key_val(skb, 1467 &p->zone, TCA_CT_ZONE, 1468 NULL, TCA_CT_UNSPEC, 1469 sizeof(p->zone))) 1470 goto nla_put_failure; 1471 1472 if (tcf_ct_dump_nat(skb, p)) 1473 goto nla_put_failure; 1474 1475 skip_dump: 1476 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt)) 1477 goto nla_put_failure; 1478 1479 tcf_tm_dump(&t, &c->tcf_tm); 1480 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD)) 1481 goto nla_put_failure; 1482 spin_unlock_bh(&c->tcf_lock); 1483 1484 return skb->len; 1485 nla_put_failure: 1486 spin_unlock_bh(&c->tcf_lock); 1487 nlmsg_trim(skb, b); 1488 return -1; 1489 } 1490 1491 static int tcf_ct_walker(struct net *net, struct sk_buff *skb, 1492 struct netlink_callback *cb, int type, 1493 const struct tc_action_ops *ops, 1494 struct netlink_ext_ack *extack) 1495 { 1496 struct tc_action_net *tn = net_generic(net, ct_net_id); 1497 1498 return tcf_generic_walker(tn, skb, cb, type, ops, extack); 1499 } 1500 1501 static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index) 1502 { 1503 struct tc_action_net *tn = net_generic(net, ct_net_id); 1504 1505 return tcf_idr_search(tn, a, index); 1506 } 1507 1508 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets, 1509 u64 drops, u64 lastuse, bool hw) 1510 { 1511 struct tcf_ct *c = to_ct(a); 1512 1513 tcf_action_update_stats(a, bytes, packets, drops, hw); 1514 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse); 1515 } 1516 1517 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data, 1518 u32 *index_inc, bool bind) 1519 { 1520 if (bind) { 1521 struct flow_action_entry *entry = entry_data; 1522 1523 entry->id = FLOW_ACTION_CT; 1524 entry->ct.action = tcf_ct_action(act); 1525 entry->ct.zone = tcf_ct_zone(act); 1526 entry->ct.flow_table = tcf_ct_ft(act); 1527 *index_inc = 1; 1528 } else { 1529 struct flow_offload_action *fl_action = entry_data; 1530 1531 fl_action->id = FLOW_ACTION_CT; 1532 } 1533 1534 return 0; 1535 } 1536 1537 static struct tc_action_ops act_ct_ops = { 1538 .kind = "ct", 1539 .id = TCA_ID_CT, 1540 .owner = THIS_MODULE, 1541 .act = tcf_ct_act, 1542 .dump = tcf_ct_dump, 1543 .init = tcf_ct_init, 1544 .cleanup = tcf_ct_cleanup, 1545 .walk = tcf_ct_walker, 1546 .lookup = tcf_ct_search, 1547 .stats_update = tcf_stats_update, 1548 .offload_act_setup = tcf_ct_offload_act_setup, 1549 .size = sizeof(struct tcf_ct), 1550 }; 1551 1552 static __net_init int ct_init_net(struct net *net) 1553 { 1554 unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8; 1555 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1556 1557 if (nf_connlabels_get(net, n_bits - 1)) { 1558 tn->labels = false; 1559 pr_err("act_ct: Failed to set connlabels length"); 1560 } else { 1561 tn->labels = true; 1562 } 1563 1564 return tc_action_net_init(net, &tn->tn, &act_ct_ops); 1565 } 1566 1567 static void __net_exit ct_exit_net(struct list_head *net_list) 1568 { 1569 struct net *net; 1570 1571 rtnl_lock(); 1572 list_for_each_entry(net, net_list, exit_list) { 1573 struct tc_ct_action_net *tn = net_generic(net, ct_net_id); 1574 1575 if (tn->labels) 1576 nf_connlabels_put(net); 1577 } 1578 rtnl_unlock(); 1579 1580 tc_action_net_exit(net_list, ct_net_id); 1581 } 1582 1583 static struct pernet_operations ct_net_ops = { 1584 .init = ct_init_net, 1585 .exit_batch = ct_exit_net, 1586 .id = &ct_net_id, 1587 .size = sizeof(struct tc_ct_action_net), 1588 }; 1589 1590 static int __init ct_init_module(void) 1591 { 1592 int err; 1593 1594 act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0); 1595 if (!act_ct_wq) 1596 return -ENOMEM; 1597 1598 err = tcf_ct_flow_tables_init(); 1599 if (err) 1600 goto err_tbl_init; 1601 1602 err = tcf_register_action(&act_ct_ops, &ct_net_ops); 1603 if (err) 1604 goto err_register; 1605 1606 err = nf_ct_extend_register(&act_ct_extend); 1607 if (err) 1608 goto err_register_extend; 1609 1610 static_branch_inc(&tcf_frag_xmit_count); 1611 1612 return 0; 1613 1614 err_register_extend: 1615 tcf_unregister_action(&act_ct_ops, &ct_net_ops); 1616 err_register: 1617 tcf_ct_flow_tables_uninit(); 1618 err_tbl_init: 1619 destroy_workqueue(act_ct_wq); 1620 return err; 1621 } 1622 1623 static void __exit ct_cleanup_module(void) 1624 { 1625 static_branch_dec(&tcf_frag_xmit_count); 1626 nf_ct_extend_unregister(&act_ct_extend); 1627 tcf_unregister_action(&act_ct_ops, &ct_net_ops); 1628 tcf_ct_flow_tables_uninit(); 1629 destroy_workqueue(act_ct_wq); 1630 } 1631 1632 module_init(ct_init_module); 1633 module_exit(ct_cleanup_module); 1634 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>"); 1635 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>"); 1636 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>"); 1637 MODULE_DESCRIPTION("Connection tracking action"); 1638 MODULE_LICENSE("GPL v2"); 1639