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 net *net, 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 write_pnet(&ct_ft->nf_ft.net, net); 307 308 __module_get(THIS_MODULE); 309 out_unlock: 310 params->ct_ft = ct_ft; 311 params->nf_ft = &ct_ft->nf_ft; 312 mutex_unlock(&zones_mutex); 313 314 return 0; 315 316 err_init: 317 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 318 err_insert: 319 kfree(ct_ft); 320 err_alloc: 321 mutex_unlock(&zones_mutex); 322 return err; 323 } 324 325 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work) 326 { 327 struct flow_block_cb *block_cb, *tmp_cb; 328 struct tcf_ct_flow_table *ct_ft; 329 struct flow_block *block; 330 331 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table, 332 rwork); 333 nf_flow_table_free(&ct_ft->nf_ft); 334 335 /* Remove any remaining callbacks before cleanup */ 336 block = &ct_ft->nf_ft.flow_block; 337 down_write(&ct_ft->nf_ft.flow_block_lock); 338 list_for_each_entry_safe(block_cb, tmp_cb, &block->cb_list, list) { 339 list_del(&block_cb->list); 340 flow_block_cb_free(block_cb); 341 } 342 up_write(&ct_ft->nf_ft.flow_block_lock); 343 kfree(ct_ft); 344 345 module_put(THIS_MODULE); 346 } 347 348 static void tcf_ct_flow_table_put(struct tcf_ct_params *params) 349 { 350 struct tcf_ct_flow_table *ct_ft = params->ct_ft; 351 352 if (refcount_dec_and_test(¶ms->ct_ft->ref)) { 353 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 354 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work); 355 queue_rcu_work(act_ct_wq, &ct_ft->rwork); 356 } 357 } 358 359 static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry, 360 struct nf_conn_act_ct_ext *act_ct_ext, u8 dir) 361 { 362 entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC; 363 entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir]; 364 } 365 366 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft, 367 struct nf_conn *ct, 368 bool tcp) 369 { 370 struct nf_conn_act_ct_ext *act_ct_ext; 371 struct flow_offload *entry; 372 int err; 373 374 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status)) 375 return; 376 377 entry = flow_offload_alloc(ct); 378 if (!entry) { 379 WARN_ON_ONCE(1); 380 goto err_alloc; 381 } 382 383 if (tcp) { 384 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 385 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 386 } 387 388 act_ct_ext = nf_conn_act_ct_ext_find(ct); 389 if (act_ct_ext) { 390 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL); 391 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_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 #ifdef CONFIG_NF_CT_PROTO_GRE 425 case IPPROTO_GRE: { 426 struct nf_conntrack_tuple *tuple; 427 428 if (ct->status & IPS_NAT_MASK) 429 return; 430 tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple; 431 /* No support for GRE v1 */ 432 if (tuple->src.u.gre.key || tuple->dst.u.gre.key) 433 return; 434 break; 435 } 436 #endif 437 default: 438 return; 439 } 440 441 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) || 442 ct->status & IPS_SEQ_ADJUST) 443 return; 444 445 tcf_ct_flow_table_add(ct_ft, ct, tcp); 446 } 447 448 static bool 449 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb, 450 struct flow_offload_tuple *tuple, 451 struct tcphdr **tcph) 452 { 453 struct flow_ports *ports; 454 unsigned int thoff; 455 struct iphdr *iph; 456 size_t hdrsize; 457 u8 ipproto; 458 459 if (!pskb_network_may_pull(skb, sizeof(*iph))) 460 return false; 461 462 iph = ip_hdr(skb); 463 thoff = iph->ihl * 4; 464 465 if (ip_is_fragment(iph) || 466 unlikely(thoff != sizeof(struct iphdr))) 467 return false; 468 469 ipproto = iph->protocol; 470 switch (ipproto) { 471 case IPPROTO_TCP: 472 hdrsize = sizeof(struct tcphdr); 473 break; 474 case IPPROTO_UDP: 475 hdrsize = sizeof(*ports); 476 break; 477 #ifdef CONFIG_NF_CT_PROTO_GRE 478 case IPPROTO_GRE: 479 hdrsize = sizeof(struct gre_base_hdr); 480 break; 481 #endif 482 default: 483 return false; 484 } 485 486 if (iph->ttl <= 1) 487 return false; 488 489 if (!pskb_network_may_pull(skb, thoff + hdrsize)) 490 return false; 491 492 switch (ipproto) { 493 case IPPROTO_TCP: 494 *tcph = (void *)(skb_network_header(skb) + thoff); 495 fallthrough; 496 case IPPROTO_UDP: 497 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 498 tuple->src_port = ports->source; 499 tuple->dst_port = ports->dest; 500 break; 501 case IPPROTO_GRE: { 502 struct gre_base_hdr *greh; 503 504 greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff); 505 if ((greh->flags & GRE_VERSION) != GRE_VERSION_0) 506 return false; 507 break; 508 } 509 } 510 511 iph = ip_hdr(skb); 512 513 tuple->src_v4.s_addr = iph->saddr; 514 tuple->dst_v4.s_addr = iph->daddr; 515 tuple->l3proto = AF_INET; 516 tuple->l4proto = ipproto; 517 518 return true; 519 } 520 521 static bool 522 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb, 523 struct flow_offload_tuple *tuple, 524 struct tcphdr **tcph) 525 { 526 struct flow_ports *ports; 527 struct ipv6hdr *ip6h; 528 unsigned int thoff; 529 size_t hdrsize; 530 u8 nexthdr; 531 532 if (!pskb_network_may_pull(skb, sizeof(*ip6h))) 533 return false; 534 535 ip6h = ipv6_hdr(skb); 536 thoff = sizeof(*ip6h); 537 538 nexthdr = ip6h->nexthdr; 539 switch (nexthdr) { 540 case IPPROTO_TCP: 541 hdrsize = sizeof(struct tcphdr); 542 break; 543 case IPPROTO_UDP: 544 hdrsize = sizeof(*ports); 545 break; 546 #ifdef CONFIG_NF_CT_PROTO_GRE 547 case IPPROTO_GRE: 548 hdrsize = sizeof(struct gre_base_hdr); 549 break; 550 #endif 551 default: 552 return false; 553 } 554 555 if (ip6h->hop_limit <= 1) 556 return false; 557 558 if (!pskb_network_may_pull(skb, thoff + hdrsize)) 559 return false; 560 561 switch (nexthdr) { 562 case IPPROTO_TCP: 563 *tcph = (void *)(skb_network_header(skb) + thoff); 564 fallthrough; 565 case IPPROTO_UDP: 566 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 567 tuple->src_port = ports->source; 568 tuple->dst_port = ports->dest; 569 break; 570 case IPPROTO_GRE: { 571 struct gre_base_hdr *greh; 572 573 greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff); 574 if ((greh->flags & GRE_VERSION) != GRE_VERSION_0) 575 return false; 576 break; 577 } 578 } 579 580 ip6h = ipv6_hdr(skb); 581 582 tuple->src_v6 = ip6h->saddr; 583 tuple->dst_v6 = ip6h->daddr; 584 tuple->l3proto = AF_INET6; 585 tuple->l4proto = nexthdr; 586 587 return true; 588 } 589 590 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p, 591 struct sk_buff *skb, 592 u8 family) 593 { 594 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft; 595 struct flow_offload_tuple_rhash *tuplehash; 596 struct flow_offload_tuple tuple = {}; 597 enum ip_conntrack_info ctinfo; 598 struct tcphdr *tcph = NULL; 599 struct flow_offload *flow; 600 struct nf_conn *ct; 601 u8 dir; 602 603 switch (family) { 604 case NFPROTO_IPV4: 605 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph)) 606 return false; 607 break; 608 case NFPROTO_IPV6: 609 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph)) 610 return false; 611 break; 612 default: 613 return false; 614 } 615 616 tuplehash = flow_offload_lookup(nf_ft, &tuple); 617 if (!tuplehash) 618 return false; 619 620 dir = tuplehash->tuple.dir; 621 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]); 622 ct = flow->ct; 623 624 if (tcph && (unlikely(tcph->fin || tcph->rst))) { 625 flow_offload_teardown(flow); 626 return false; 627 } 628 629 ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED : 630 IP_CT_ESTABLISHED_REPLY; 631 632 flow_offload_refresh(nf_ft, flow); 633 nf_conntrack_get(&ct->ct_general); 634 nf_ct_set(skb, ct, ctinfo); 635 if (nf_ft->flags & NF_FLOWTABLE_COUNTER) 636 nf_ct_acct_update(ct, dir, skb->len); 637 638 return true; 639 } 640 641 static int tcf_ct_flow_tables_init(void) 642 { 643 return rhashtable_init(&zones_ht, &zones_params); 644 } 645 646 static void tcf_ct_flow_tables_uninit(void) 647 { 648 rhashtable_destroy(&zones_ht); 649 } 650 651 static struct tc_action_ops act_ct_ops; 652 653 struct tc_ct_action_net { 654 struct tc_action_net tn; /* Must be first */ 655 bool labels; 656 }; 657 658 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ 659 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb, 660 u16 zone_id, bool force) 661 { 662 enum ip_conntrack_info ctinfo; 663 struct nf_conn *ct; 664 665 ct = nf_ct_get(skb, &ctinfo); 666 if (!ct) 667 return false; 668 if (!net_eq(net, read_pnet(&ct->ct_net))) 669 goto drop_ct; 670 if (nf_ct_zone(ct)->id != zone_id) 671 goto drop_ct; 672 673 /* Force conntrack entry direction. */ 674 if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 675 if (nf_ct_is_confirmed(ct)) 676 nf_ct_kill(ct); 677 678 goto drop_ct; 679 } 680 681 return true; 682 683 drop_ct: 684 nf_ct_put(ct); 685 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 686 687 return false; 688 } 689 690 /* Trim the skb to the length specified by the IP/IPv6 header, 691 * removing any trailing lower-layer padding. This prepares the skb 692 * for higher-layer processing that assumes skb->len excludes padding 693 * (such as nf_ip_checksum). The caller needs to pull the skb to the 694 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 695 */ 696 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family) 697 { 698 unsigned int len; 699 700 switch (family) { 701 case NFPROTO_IPV4: 702 len = ntohs(ip_hdr(skb)->tot_len); 703 break; 704 case NFPROTO_IPV6: 705 len = sizeof(struct ipv6hdr) 706 + ntohs(ipv6_hdr(skb)->payload_len); 707 break; 708 default: 709 len = skb->len; 710 } 711 712 return pskb_trim_rcsum(skb, len); 713 } 714 715 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb) 716 { 717 u8 family = NFPROTO_UNSPEC; 718 719 switch (skb_protocol(skb, true)) { 720 case htons(ETH_P_IP): 721 family = NFPROTO_IPV4; 722 break; 723 case htons(ETH_P_IPV6): 724 family = NFPROTO_IPV6; 725 break; 726 default: 727 break; 728 } 729 730 return family; 731 } 732 733 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag) 734 { 735 unsigned int len; 736 737 len = skb_network_offset(skb) + sizeof(struct iphdr); 738 if (unlikely(skb->len < len)) 739 return -EINVAL; 740 if (unlikely(!pskb_may_pull(skb, len))) 741 return -ENOMEM; 742 743 *frag = ip_is_fragment(ip_hdr(skb)); 744 return 0; 745 } 746 747 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag) 748 { 749 unsigned int flags = 0, len, payload_ofs = 0; 750 unsigned short frag_off; 751 int nexthdr; 752 753 len = skb_network_offset(skb) + sizeof(struct ipv6hdr); 754 if (unlikely(skb->len < len)) 755 return -EINVAL; 756 if (unlikely(!pskb_may_pull(skb, len))) 757 return -ENOMEM; 758 759 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags); 760 if (unlikely(nexthdr < 0)) 761 return -EPROTO; 762 763 *frag = flags & IP6_FH_F_FRAG; 764 return 0; 765 } 766 767 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 768 u8 family, u16 zone, bool *defrag) 769 { 770 enum ip_conntrack_info ctinfo; 771 struct nf_conn *ct; 772 int err = 0; 773 bool frag; 774 u16 mru; 775 776 /* Previously seen (loopback)? Ignore. */ 777 ct = nf_ct_get(skb, &ctinfo); 778 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED) 779 return 0; 780 781 if (family == NFPROTO_IPV4) 782 err = tcf_ct_ipv4_is_fragment(skb, &frag); 783 else 784 err = tcf_ct_ipv6_is_fragment(skb, &frag); 785 if (err || !frag) 786 return err; 787 788 skb_get(skb); 789 mru = tc_skb_cb(skb)->mru; 790 791 if (family == NFPROTO_IPV4) { 792 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; 793 794 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 795 local_bh_disable(); 796 err = ip_defrag(net, skb, user); 797 local_bh_enable(); 798 if (err && err != -EINPROGRESS) 799 return err; 800 801 if (!err) { 802 *defrag = true; 803 mru = IPCB(skb)->frag_max_size; 804 } 805 } else { /* NFPROTO_IPV6 */ 806 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 807 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; 808 809 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); 810 err = nf_ct_frag6_gather(net, skb, user); 811 if (err && err != -EINPROGRESS) 812 goto out_free; 813 814 if (!err) { 815 *defrag = true; 816 mru = IP6CB(skb)->frag_max_size; 817 } 818 #else 819 err = -EOPNOTSUPP; 820 goto out_free; 821 #endif 822 } 823 824 if (err != -EINPROGRESS) 825 tc_skb_cb(skb)->mru = mru; 826 skb_clear_hash(skb); 827 skb->ignore_df = 1; 828 return err; 829 830 out_free: 831 kfree_skb(skb); 832 return err; 833 } 834 835 static void tcf_ct_params_free(struct rcu_head *head) 836 { 837 struct tcf_ct_params *params = container_of(head, 838 struct tcf_ct_params, rcu); 839 840 tcf_ct_flow_table_put(params); 841 842 if (params->tmpl) 843 nf_ct_put(params->tmpl); 844 kfree(params); 845 } 846 847 #if IS_ENABLED(CONFIG_NF_NAT) 848 /* Modelled after nf_nat_ipv[46]_fn(). 849 * range is only used for new, uninitialized NAT state. 850 * Returns either NF_ACCEPT or NF_DROP. 851 */ 852 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, 853 enum ip_conntrack_info ctinfo, 854 const struct nf_nat_range2 *range, 855 enum nf_nat_manip_type maniptype) 856 { 857 __be16 proto = skb_protocol(skb, true); 858 int hooknum, err = NF_ACCEPT; 859 860 /* See HOOK2MANIP(). */ 861 if (maniptype == NF_NAT_MANIP_SRC) 862 hooknum = NF_INET_LOCAL_IN; /* Source NAT */ 863 else 864 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ 865 866 switch (ctinfo) { 867 case IP_CT_RELATED: 868 case IP_CT_RELATED_REPLY: 869 if (proto == htons(ETH_P_IP) && 870 ip_hdr(skb)->protocol == IPPROTO_ICMP) { 871 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, 872 hooknum)) 873 err = NF_DROP; 874 goto out; 875 } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) { 876 __be16 frag_off; 877 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 878 int hdrlen = ipv6_skip_exthdr(skb, 879 sizeof(struct ipv6hdr), 880 &nexthdr, &frag_off); 881 882 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { 883 if (!nf_nat_icmpv6_reply_translation(skb, ct, 884 ctinfo, 885 hooknum, 886 hdrlen)) 887 err = NF_DROP; 888 goto out; 889 } 890 } 891 /* Non-ICMP, fall thru to initialize if needed. */ 892 fallthrough; 893 case IP_CT_NEW: 894 /* Seen it before? This can happen for loopback, retrans, 895 * or local packets. 896 */ 897 if (!nf_nat_initialized(ct, maniptype)) { 898 /* Initialize according to the NAT action. */ 899 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) 900 /* Action is set up to establish a new 901 * mapping. 902 */ 903 ? nf_nat_setup_info(ct, range, maniptype) 904 : nf_nat_alloc_null_binding(ct, hooknum); 905 if (err != NF_ACCEPT) 906 goto out; 907 } 908 break; 909 910 case IP_CT_ESTABLISHED: 911 case IP_CT_ESTABLISHED_REPLY: 912 break; 913 914 default: 915 err = NF_DROP; 916 goto out; 917 } 918 919 err = nf_nat_packet(ct, ctinfo, hooknum, skb); 920 if (err == NF_ACCEPT) { 921 if (maniptype == NF_NAT_MANIP_SRC) 922 tc_skb_cb(skb)->post_ct_snat = 1; 923 if (maniptype == NF_NAT_MANIP_DST) 924 tc_skb_cb(skb)->post_ct_dnat = 1; 925 } 926 out: 927 return err; 928 } 929 #endif /* CONFIG_NF_NAT */ 930 931 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask) 932 { 933 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 934 u32 new_mark; 935 936 if (!mask) 937 return; 938 939 new_mark = mark | (ct->mark & ~(mask)); 940 if (ct->mark != new_mark) { 941 ct->mark = new_mark; 942 if (nf_ct_is_confirmed(ct)) 943 nf_conntrack_event_cache(IPCT_MARK, ct); 944 } 945 #endif 946 } 947 948 static void tcf_ct_act_set_labels(struct nf_conn *ct, 949 u32 *labels, 950 u32 *labels_m) 951 { 952 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) 953 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels); 954 955 if (!memchr_inv(labels_m, 0, labels_sz)) 956 return; 957 958 nf_connlabels_replace(ct, labels, labels_m, 4); 959 #endif 960 } 961 962 static int tcf_ct_act_nat(struct sk_buff *skb, 963 struct nf_conn *ct, 964 enum ip_conntrack_info ctinfo, 965 int ct_action, 966 struct nf_nat_range2 *range, 967 bool commit) 968 { 969 #if IS_ENABLED(CONFIG_NF_NAT) 970 int err; 971 enum nf_nat_manip_type maniptype; 972 973 if (!(ct_action & TCA_CT_ACT_NAT)) 974 return NF_ACCEPT; 975 976 /* Add NAT extension if not confirmed yet. */ 977 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) 978 return NF_DROP; /* Can't NAT. */ 979 980 if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) && 981 (ctinfo != IP_CT_RELATED || commit)) { 982 /* NAT an established or related connection like before. */ 983 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) 984 /* This is the REPLY direction for a connection 985 * for which NAT was applied in the forward 986 * direction. Do the reverse NAT. 987 */ 988 maniptype = ct->status & IPS_SRC_NAT 989 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; 990 else 991 maniptype = ct->status & IPS_SRC_NAT 992 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; 993 } else if (ct_action & TCA_CT_ACT_NAT_SRC) { 994 maniptype = NF_NAT_MANIP_SRC; 995 } else if (ct_action & TCA_CT_ACT_NAT_DST) { 996 maniptype = NF_NAT_MANIP_DST; 997 } else { 998 return NF_ACCEPT; 999 } 1000 1001 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype); 1002 if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) { 1003 if (ct->status & IPS_SRC_NAT) { 1004 if (maniptype == NF_NAT_MANIP_SRC) 1005 maniptype = NF_NAT_MANIP_DST; 1006 else 1007 maniptype = NF_NAT_MANIP_SRC; 1008 1009 err = ct_nat_execute(skb, ct, ctinfo, range, 1010 maniptype); 1011 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) { 1012 err = ct_nat_execute(skb, ct, ctinfo, NULL, 1013 NF_NAT_MANIP_SRC); 1014 } 1015 } 1016 return err; 1017 #else 1018 return NF_ACCEPT; 1019 #endif 1020 } 1021 1022 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 1023 struct tcf_result *res) 1024 { 1025 struct net *net = dev_net(skb->dev); 1026 bool cached, commit, clear, force; 1027 enum ip_conntrack_info ctinfo; 1028 struct tcf_ct *c = to_ct(a); 1029 struct nf_conn *tmpl = NULL; 1030 struct nf_hook_state state; 1031 int nh_ofs, err, retval; 1032 struct tcf_ct_params *p; 1033 bool skip_add = false; 1034 bool defrag = false; 1035 struct nf_conn *ct; 1036 u8 family; 1037 1038 p = rcu_dereference_bh(c->params); 1039 1040 retval = READ_ONCE(c->tcf_action); 1041 commit = p->ct_action & TCA_CT_ACT_COMMIT; 1042 clear = p->ct_action & TCA_CT_ACT_CLEAR; 1043 force = p->ct_action & TCA_CT_ACT_FORCE; 1044 tmpl = p->tmpl; 1045 1046 tcf_lastuse_update(&c->tcf_tm); 1047 tcf_action_update_bstats(&c->common, skb); 1048 1049 if (clear) { 1050 tc_skb_cb(skb)->post_ct = false; 1051 ct = nf_ct_get(skb, &ctinfo); 1052 if (ct) { 1053 nf_ct_put(ct); 1054 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 1055 } 1056 1057 goto out_clear; 1058 } 1059 1060 family = tcf_ct_skb_nf_family(skb); 1061 if (family == NFPROTO_UNSPEC) 1062 goto drop; 1063 1064 /* The conntrack module expects to be working at L3. 1065 * We also try to pull the IPv4/6 header to linear area 1066 */ 1067 nh_ofs = skb_network_offset(skb); 1068 skb_pull_rcsum(skb, nh_ofs); 1069 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag); 1070 if (err == -EINPROGRESS) { 1071 retval = TC_ACT_STOLEN; 1072 goto out_clear; 1073 } 1074 if (err) 1075 goto drop; 1076 1077 err = tcf_ct_skb_network_trim(skb, family); 1078 if (err) 1079 goto drop; 1080 1081 /* If we are recirculating packets to match on ct fields and 1082 * committing with a separate ct action, then we don't need to 1083 * actually run the packet through conntrack twice unless it's for a 1084 * different zone. 1085 */ 1086 cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force); 1087 if (!cached) { 1088 if (tcf_ct_flow_table_lookup(p, skb, family)) { 1089 skip_add = true; 1090 goto do_nat; 1091 } 1092 1093 /* Associate skb with specified zone. */ 1094 if (tmpl) { 1095 nf_conntrack_put(skb_nfct(skb)); 1096 nf_conntrack_get(&tmpl->ct_general); 1097 nf_ct_set(skb, tmpl, IP_CT_NEW); 1098 } 1099 1100 state.hook = NF_INET_PRE_ROUTING; 1101 state.net = net; 1102 state.pf = family; 1103 err = nf_conntrack_in(skb, &state); 1104 if (err != NF_ACCEPT) 1105 goto out_push; 1106 } 1107 1108 do_nat: 1109 ct = nf_ct_get(skb, &ctinfo); 1110 if (!ct) 1111 goto out_push; 1112 nf_ct_deliver_cached_events(ct); 1113 nf_conn_act_ct_ext_fill(skb, ct, ctinfo); 1114 1115 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit); 1116 if (err != NF_ACCEPT) 1117 goto drop; 1118 1119 if (commit) { 1120 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask); 1121 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask); 1122 1123 if (!nf_ct_is_confirmed(ct)) 1124 nf_conn_act_ct_ext_add(ct); 1125 1126 /* This will take care of sending queued events 1127 * even if the connection is already confirmed. 1128 */ 1129 if (nf_conntrack_confirm(skb) != NF_ACCEPT) 1130 goto drop; 1131 } 1132 1133 if (!skip_add) 1134 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo); 1135 1136 out_push: 1137 skb_push_rcsum(skb, nh_ofs); 1138 1139 tc_skb_cb(skb)->post_ct = true; 1140 tc_skb_cb(skb)->zone = p->zone; 1141 out_clear: 1142 if (defrag) 1143 qdisc_skb_cb(skb)->pkt_len = skb->len; 1144 return retval; 1145 1146 drop: 1147 tcf_action_inc_drop_qstats(&c->common); 1148 return TC_ACT_SHOT; 1149 } 1150 1151 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = { 1152 [TCA_CT_ACTION] = { .type = NLA_U16 }, 1153 [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)), 1154 [TCA_CT_ZONE] = { .type = NLA_U16 }, 1155 [TCA_CT_MARK] = { .type = NLA_U32 }, 1156 [TCA_CT_MARK_MASK] = { .type = NLA_U32 }, 1157 [TCA_CT_LABELS] = { .type = NLA_BINARY, 1158 .len = 128 / BITS_PER_BYTE }, 1159 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY, 1160 .len = 128 / BITS_PER_BYTE }, 1161 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 }, 1162 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 }, 1163 [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1164 [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1165 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 }, 1166 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 }, 1167 }; 1168 1169 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p, 1170 struct tc_ct *parm, 1171 struct nlattr **tb, 1172 struct netlink_ext_ack *extack) 1173 { 1174 struct nf_nat_range2 *range; 1175 1176 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1177 return 0; 1178 1179 if (!IS_ENABLED(CONFIG_NF_NAT)) { 1180 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel"); 1181 return -EOPNOTSUPP; 1182 } 1183 1184 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1185 return 0; 1186 1187 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) && 1188 (p->ct_action & TCA_CT_ACT_NAT_DST)) { 1189 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time"); 1190 return -EOPNOTSUPP; 1191 } 1192 1193 range = &p->range; 1194 if (tb[TCA_CT_NAT_IPV4_MIN]) { 1195 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX]; 1196 1197 p->ipv4_range = true; 1198 range->flags |= NF_NAT_RANGE_MAP_IPS; 1199 range->min_addr.ip = 1200 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]); 1201 1202 range->max_addr.ip = max_attr ? 1203 nla_get_in_addr(max_attr) : 1204 range->min_addr.ip; 1205 } else if (tb[TCA_CT_NAT_IPV6_MIN]) { 1206 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX]; 1207 1208 p->ipv4_range = false; 1209 range->flags |= NF_NAT_RANGE_MAP_IPS; 1210 range->min_addr.in6 = 1211 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]); 1212 1213 range->max_addr.in6 = max_attr ? 1214 nla_get_in6_addr(max_attr) : 1215 range->min_addr.in6; 1216 } 1217 1218 if (tb[TCA_CT_NAT_PORT_MIN]) { 1219 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1220 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]); 1221 1222 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ? 1223 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) : 1224 range->min_proto.all; 1225 } 1226 1227 return 0; 1228 } 1229 1230 static void tcf_ct_set_key_val(struct nlattr **tb, 1231 void *val, int val_type, 1232 void *mask, int mask_type, 1233 int len) 1234 { 1235 if (!tb[val_type]) 1236 return; 1237 nla_memcpy(val, tb[val_type], len); 1238 1239 if (!mask) 1240 return; 1241 1242 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type]) 1243 memset(mask, 0xff, len); 1244 else 1245 nla_memcpy(mask, tb[mask_type], len); 1246 } 1247 1248 static int tcf_ct_fill_params(struct net *net, 1249 struct tcf_ct_params *p, 1250 struct tc_ct *parm, 1251 struct nlattr **tb, 1252 struct netlink_ext_ack *extack) 1253 { 1254 struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id); 1255 struct nf_conntrack_zone zone; 1256 struct nf_conn *tmpl; 1257 int err; 1258 1259 p->zone = NF_CT_DEFAULT_ZONE_ID; 1260 1261 tcf_ct_set_key_val(tb, 1262 &p->ct_action, TCA_CT_ACTION, 1263 NULL, TCA_CT_UNSPEC, 1264 sizeof(p->ct_action)); 1265 1266 if (p->ct_action & TCA_CT_ACT_CLEAR) 1267 return 0; 1268 1269 err = tcf_ct_fill_params_nat(p, parm, tb, extack); 1270 if (err) 1271 return err; 1272 1273 if (tb[TCA_CT_MARK]) { 1274 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) { 1275 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled."); 1276 return -EOPNOTSUPP; 1277 } 1278 tcf_ct_set_key_val(tb, 1279 &p->mark, TCA_CT_MARK, 1280 &p->mark_mask, TCA_CT_MARK_MASK, 1281 sizeof(p->mark)); 1282 } 1283 1284 if (tb[TCA_CT_LABELS]) { 1285 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) { 1286 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled."); 1287 return -EOPNOTSUPP; 1288 } 1289 1290 if (!tn->labels) { 1291 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length"); 1292 return -EOPNOTSUPP; 1293 } 1294 tcf_ct_set_key_val(tb, 1295 p->labels, TCA_CT_LABELS, 1296 p->labels_mask, TCA_CT_LABELS_MASK, 1297 sizeof(p->labels)); 1298 } 1299 1300 if (tb[TCA_CT_ZONE]) { 1301 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) { 1302 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled."); 1303 return -EOPNOTSUPP; 1304 } 1305 1306 tcf_ct_set_key_val(tb, 1307 &p->zone, TCA_CT_ZONE, 1308 NULL, TCA_CT_UNSPEC, 1309 sizeof(p->zone)); 1310 } 1311 1312 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0); 1313 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL); 1314 if (!tmpl) { 1315 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template"); 1316 return -ENOMEM; 1317 } 1318 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status); 1319 p->tmpl = tmpl; 1320 1321 return 0; 1322 } 1323 1324 static int tcf_ct_init(struct net *net, struct nlattr *nla, 1325 struct nlattr *est, struct tc_action **a, 1326 struct tcf_proto *tp, u32 flags, 1327 struct netlink_ext_ack *extack) 1328 { 1329 struct tc_action_net *tn = net_generic(net, act_ct_ops.net_id); 1330 bool bind = flags & TCA_ACT_FLAGS_BIND; 1331 struct tcf_ct_params *params = NULL; 1332 struct nlattr *tb[TCA_CT_MAX + 1]; 1333 struct tcf_chain *goto_ch = NULL; 1334 struct tc_ct *parm; 1335 struct tcf_ct *c; 1336 int err, res = 0; 1337 u32 index; 1338 1339 if (!nla) { 1340 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed"); 1341 return -EINVAL; 1342 } 1343 1344 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack); 1345 if (err < 0) 1346 return err; 1347 1348 if (!tb[TCA_CT_PARMS]) { 1349 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters"); 1350 return -EINVAL; 1351 } 1352 parm = nla_data(tb[TCA_CT_PARMS]); 1353 index = parm->index; 1354 err = tcf_idr_check_alloc(tn, &index, a, bind); 1355 if (err < 0) 1356 return err; 1357 1358 if (!err) { 1359 err = tcf_idr_create_from_flags(tn, index, est, a, 1360 &act_ct_ops, bind, flags); 1361 if (err) { 1362 tcf_idr_cleanup(tn, index); 1363 return err; 1364 } 1365 res = ACT_P_CREATED; 1366 } else { 1367 if (bind) 1368 return 0; 1369 1370 if (!(flags & TCA_ACT_FLAGS_REPLACE)) { 1371 tcf_idr_release(*a, bind); 1372 return -EEXIST; 1373 } 1374 } 1375 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 1376 if (err < 0) 1377 goto cleanup; 1378 1379 c = to_ct(*a); 1380 1381 params = kzalloc(sizeof(*params), GFP_KERNEL); 1382 if (unlikely(!params)) { 1383 err = -ENOMEM; 1384 goto cleanup; 1385 } 1386 1387 err = tcf_ct_fill_params(net, params, parm, tb, extack); 1388 if (err) 1389 goto cleanup; 1390 1391 err = tcf_ct_flow_table_get(net, params); 1392 if (err) 1393 goto cleanup_params; 1394 1395 spin_lock_bh(&c->tcf_lock); 1396 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 1397 params = rcu_replace_pointer(c->params, params, 1398 lockdep_is_held(&c->tcf_lock)); 1399 spin_unlock_bh(&c->tcf_lock); 1400 1401 if (goto_ch) 1402 tcf_chain_put_by_act(goto_ch); 1403 if (params) 1404 call_rcu(¶ms->rcu, tcf_ct_params_free); 1405 1406 return res; 1407 1408 cleanup_params: 1409 if (params->tmpl) 1410 nf_ct_put(params->tmpl); 1411 cleanup: 1412 if (goto_ch) 1413 tcf_chain_put_by_act(goto_ch); 1414 kfree(params); 1415 tcf_idr_release(*a, bind); 1416 return err; 1417 } 1418 1419 static void tcf_ct_cleanup(struct tc_action *a) 1420 { 1421 struct tcf_ct_params *params; 1422 struct tcf_ct *c = to_ct(a); 1423 1424 params = rcu_dereference_protected(c->params, 1); 1425 if (params) 1426 call_rcu(¶ms->rcu, tcf_ct_params_free); 1427 } 1428 1429 static int tcf_ct_dump_key_val(struct sk_buff *skb, 1430 void *val, int val_type, 1431 void *mask, int mask_type, 1432 int len) 1433 { 1434 int err; 1435 1436 if (mask && !memchr_inv(mask, 0, len)) 1437 return 0; 1438 1439 err = nla_put(skb, val_type, len, val); 1440 if (err) 1441 return err; 1442 1443 if (mask_type != TCA_CT_UNSPEC) { 1444 err = nla_put(skb, mask_type, len, mask); 1445 if (err) 1446 return err; 1447 } 1448 1449 return 0; 1450 } 1451 1452 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p) 1453 { 1454 struct nf_nat_range2 *range = &p->range; 1455 1456 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1457 return 0; 1458 1459 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1460 return 0; 1461 1462 if (range->flags & NF_NAT_RANGE_MAP_IPS) { 1463 if (p->ipv4_range) { 1464 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN, 1465 range->min_addr.ip)) 1466 return -1; 1467 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX, 1468 range->max_addr.ip)) 1469 return -1; 1470 } else { 1471 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN, 1472 &range->min_addr.in6)) 1473 return -1; 1474 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX, 1475 &range->max_addr.in6)) 1476 return -1; 1477 } 1478 } 1479 1480 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) { 1481 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN, 1482 range->min_proto.all)) 1483 return -1; 1484 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX, 1485 range->max_proto.all)) 1486 return -1; 1487 } 1488 1489 return 0; 1490 } 1491 1492 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a, 1493 int bind, int ref) 1494 { 1495 unsigned char *b = skb_tail_pointer(skb); 1496 struct tcf_ct *c = to_ct(a); 1497 struct tcf_ct_params *p; 1498 1499 struct tc_ct opt = { 1500 .index = c->tcf_index, 1501 .refcnt = refcount_read(&c->tcf_refcnt) - ref, 1502 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind, 1503 }; 1504 struct tcf_t t; 1505 1506 spin_lock_bh(&c->tcf_lock); 1507 p = rcu_dereference_protected(c->params, 1508 lockdep_is_held(&c->tcf_lock)); 1509 opt.action = c->tcf_action; 1510 1511 if (tcf_ct_dump_key_val(skb, 1512 &p->ct_action, TCA_CT_ACTION, 1513 NULL, TCA_CT_UNSPEC, 1514 sizeof(p->ct_action))) 1515 goto nla_put_failure; 1516 1517 if (p->ct_action & TCA_CT_ACT_CLEAR) 1518 goto skip_dump; 1519 1520 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1521 tcf_ct_dump_key_val(skb, 1522 &p->mark, TCA_CT_MARK, 1523 &p->mark_mask, TCA_CT_MARK_MASK, 1524 sizeof(p->mark))) 1525 goto nla_put_failure; 1526 1527 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1528 tcf_ct_dump_key_val(skb, 1529 p->labels, TCA_CT_LABELS, 1530 p->labels_mask, TCA_CT_LABELS_MASK, 1531 sizeof(p->labels))) 1532 goto nla_put_failure; 1533 1534 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1535 tcf_ct_dump_key_val(skb, 1536 &p->zone, TCA_CT_ZONE, 1537 NULL, TCA_CT_UNSPEC, 1538 sizeof(p->zone))) 1539 goto nla_put_failure; 1540 1541 if (tcf_ct_dump_nat(skb, p)) 1542 goto nla_put_failure; 1543 1544 skip_dump: 1545 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt)) 1546 goto nla_put_failure; 1547 1548 tcf_tm_dump(&t, &c->tcf_tm); 1549 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD)) 1550 goto nla_put_failure; 1551 spin_unlock_bh(&c->tcf_lock); 1552 1553 return skb->len; 1554 nla_put_failure: 1555 spin_unlock_bh(&c->tcf_lock); 1556 nlmsg_trim(skb, b); 1557 return -1; 1558 } 1559 1560 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets, 1561 u64 drops, u64 lastuse, bool hw) 1562 { 1563 struct tcf_ct *c = to_ct(a); 1564 1565 tcf_action_update_stats(a, bytes, packets, drops, hw); 1566 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse); 1567 } 1568 1569 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data, 1570 u32 *index_inc, bool bind, 1571 struct netlink_ext_ack *extack) 1572 { 1573 if (bind) { 1574 struct flow_action_entry *entry = entry_data; 1575 1576 entry->id = FLOW_ACTION_CT; 1577 entry->ct.action = tcf_ct_action(act); 1578 entry->ct.zone = tcf_ct_zone(act); 1579 entry->ct.flow_table = tcf_ct_ft(act); 1580 *index_inc = 1; 1581 } else { 1582 struct flow_offload_action *fl_action = entry_data; 1583 1584 fl_action->id = FLOW_ACTION_CT; 1585 } 1586 1587 return 0; 1588 } 1589 1590 static struct tc_action_ops act_ct_ops = { 1591 .kind = "ct", 1592 .id = TCA_ID_CT, 1593 .owner = THIS_MODULE, 1594 .act = tcf_ct_act, 1595 .dump = tcf_ct_dump, 1596 .init = tcf_ct_init, 1597 .cleanup = tcf_ct_cleanup, 1598 .stats_update = tcf_stats_update, 1599 .offload_act_setup = tcf_ct_offload_act_setup, 1600 .size = sizeof(struct tcf_ct), 1601 }; 1602 1603 static __net_init int ct_init_net(struct net *net) 1604 { 1605 unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8; 1606 struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id); 1607 1608 if (nf_connlabels_get(net, n_bits - 1)) { 1609 tn->labels = false; 1610 pr_err("act_ct: Failed to set connlabels length"); 1611 } else { 1612 tn->labels = true; 1613 } 1614 1615 return tc_action_net_init(net, &tn->tn, &act_ct_ops); 1616 } 1617 1618 static void __net_exit ct_exit_net(struct list_head *net_list) 1619 { 1620 struct net *net; 1621 1622 rtnl_lock(); 1623 list_for_each_entry(net, net_list, exit_list) { 1624 struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id); 1625 1626 if (tn->labels) 1627 nf_connlabels_put(net); 1628 } 1629 rtnl_unlock(); 1630 1631 tc_action_net_exit(net_list, act_ct_ops.net_id); 1632 } 1633 1634 static struct pernet_operations ct_net_ops = { 1635 .init = ct_init_net, 1636 .exit_batch = ct_exit_net, 1637 .id = &act_ct_ops.net_id, 1638 .size = sizeof(struct tc_ct_action_net), 1639 }; 1640 1641 static int __init ct_init_module(void) 1642 { 1643 int err; 1644 1645 act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0); 1646 if (!act_ct_wq) 1647 return -ENOMEM; 1648 1649 err = tcf_ct_flow_tables_init(); 1650 if (err) 1651 goto err_tbl_init; 1652 1653 err = tcf_register_action(&act_ct_ops, &ct_net_ops); 1654 if (err) 1655 goto err_register; 1656 1657 static_branch_inc(&tcf_frag_xmit_count); 1658 1659 return 0; 1660 1661 err_register: 1662 tcf_ct_flow_tables_uninit(); 1663 err_tbl_init: 1664 destroy_workqueue(act_ct_wq); 1665 return err; 1666 } 1667 1668 static void __exit ct_cleanup_module(void) 1669 { 1670 static_branch_dec(&tcf_frag_xmit_count); 1671 tcf_unregister_action(&act_ct_ops, &ct_net_ops); 1672 tcf_ct_flow_tables_uninit(); 1673 destroy_workqueue(act_ct_wq); 1674 } 1675 1676 module_init(ct_init_module); 1677 module_exit(ct_cleanup_module); 1678 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>"); 1679 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>"); 1680 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>"); 1681 MODULE_DESCRIPTION("Connection tracking action"); 1682 MODULE_LICENSE("GPL v2"); 1683