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/if_tunnel.h> 17 #include <linux/ip.h> 18 #include <linux/ipv6.h> 19 #include <linux/rhashtable.h> 20 #include <net/gre.h> 21 #include <net/netlink.h> 22 #include <net/pkt_sched.h> 23 #include <net/pkt_cls.h> 24 #include <net/act_api.h> 25 #include <net/ip.h> 26 #include <net/ipv6_frag.h> 27 #include <uapi/linux/tc_act/tc_ct.h> 28 #include <net/tc_act/tc_ct.h> 29 #include <net/tc_wrapper.h> 30 31 #include <net/netfilter/nf_flow_table.h> 32 #include <net/netfilter/nf_conntrack.h> 33 #include <net/netfilter/nf_conntrack_core.h> 34 #include <net/netfilter/nf_conntrack_zones.h> 35 #include <net/netfilter/nf_conntrack_helper.h> 36 #include <net/netfilter/nf_conntrack_acct.h> 37 #include <net/netfilter/ipv6/nf_defrag_ipv6.h> 38 #include <net/netfilter/nf_conntrack_act_ct.h> 39 #include <net/netfilter/nf_conntrack_seqadj.h> 40 #include <uapi/linux/netfilter/nf_nat.h> 41 42 static struct workqueue_struct *act_ct_wq; 43 static struct rhashtable zones_ht; 44 static DEFINE_MUTEX(zones_mutex); 45 46 struct zones_ht_key { 47 struct net *net; 48 u16 zone; 49 }; 50 51 struct tcf_ct_flow_table { 52 struct rhash_head node; /* In zones tables */ 53 54 struct rcu_work rwork; 55 struct nf_flowtable nf_ft; 56 refcount_t ref; 57 struct zones_ht_key key; 58 59 bool dying; 60 }; 61 62 static const struct rhashtable_params zones_params = { 63 .head_offset = offsetof(struct tcf_ct_flow_table, node), 64 .key_offset = offsetof(struct tcf_ct_flow_table, key), 65 .key_len = offsetofend(struct zones_ht_key, zone), 66 .automatic_shrinking = true, 67 }; 68 69 static struct flow_action_entry * 70 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action) 71 { 72 int i = flow_action->num_entries++; 73 74 return &flow_action->entries[i]; 75 } 76 77 static void tcf_ct_add_mangle_action(struct flow_action *action, 78 enum flow_action_mangle_base htype, 79 u32 offset, 80 u32 mask, 81 u32 val) 82 { 83 struct flow_action_entry *entry; 84 85 entry = tcf_ct_flow_table_flow_action_get_next(action); 86 entry->id = FLOW_ACTION_MANGLE; 87 entry->mangle.htype = htype; 88 entry->mangle.mask = ~mask; 89 entry->mangle.offset = offset; 90 entry->mangle.val = val; 91 } 92 93 /* The following nat helper functions check if the inverted reverse tuple 94 * (target) is different then the current dir tuple - meaning nat for ports 95 * and/or ip is needed, and add the relevant mangle actions. 96 */ 97 static void 98 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple, 99 struct nf_conntrack_tuple target, 100 struct flow_action *action) 101 { 102 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) 103 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, 104 offsetof(struct iphdr, saddr), 105 0xFFFFFFFF, 106 be32_to_cpu(target.src.u3.ip)); 107 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) 108 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4, 109 offsetof(struct iphdr, daddr), 110 0xFFFFFFFF, 111 be32_to_cpu(target.dst.u3.ip)); 112 } 113 114 static void 115 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action, 116 union nf_inet_addr *addr, 117 u32 offset) 118 { 119 int i; 120 121 for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++) 122 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6, 123 i * sizeof(u32) + offset, 124 0xFFFFFFFF, be32_to_cpu(addr->ip6[i])); 125 } 126 127 static void 128 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple, 129 struct nf_conntrack_tuple target, 130 struct flow_action *action) 131 { 132 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3))) 133 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3, 134 offsetof(struct ipv6hdr, 135 saddr)); 136 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3))) 137 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3, 138 offsetof(struct ipv6hdr, 139 daddr)); 140 } 141 142 static void 143 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple, 144 struct nf_conntrack_tuple target, 145 struct flow_action *action) 146 { 147 __be16 target_src = target.src.u.tcp.port; 148 __be16 target_dst = target.dst.u.tcp.port; 149 150 if (target_src != tuple->src.u.tcp.port) 151 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, 152 offsetof(struct tcphdr, source), 153 0xFFFF, be16_to_cpu(target_src)); 154 if (target_dst != tuple->dst.u.tcp.port) 155 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP, 156 offsetof(struct tcphdr, dest), 157 0xFFFF, be16_to_cpu(target_dst)); 158 } 159 160 static void 161 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple, 162 struct nf_conntrack_tuple target, 163 struct flow_action *action) 164 { 165 __be16 target_src = target.src.u.udp.port; 166 __be16 target_dst = target.dst.u.udp.port; 167 168 if (target_src != tuple->src.u.udp.port) 169 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP, 170 offsetof(struct udphdr, source), 171 0xFFFF, be16_to_cpu(target_src)); 172 if (target_dst != tuple->dst.u.udp.port) 173 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP, 174 offsetof(struct udphdr, dest), 175 0xFFFF, be16_to_cpu(target_dst)); 176 } 177 178 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct, 179 enum ip_conntrack_dir dir, 180 enum ip_conntrack_info ctinfo, 181 struct flow_action *action) 182 { 183 struct nf_conn_labels *ct_labels; 184 struct flow_action_entry *entry; 185 u32 *act_ct_labels; 186 187 entry = tcf_ct_flow_table_flow_action_get_next(action); 188 entry->id = FLOW_ACTION_CT_METADATA; 189 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 190 entry->ct_metadata.mark = READ_ONCE(ct->mark); 191 #endif 192 /* aligns with the CT reference on the SKB nf_ct_set */ 193 entry->ct_metadata.cookie = (unsigned long)ct | ctinfo; 194 entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL; 195 196 act_ct_labels = entry->ct_metadata.labels; 197 ct_labels = nf_ct_labels_find(ct); 198 if (ct_labels) 199 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE); 200 else 201 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE); 202 } 203 204 static int tcf_ct_flow_table_add_action_nat(struct net *net, 205 struct nf_conn *ct, 206 enum ip_conntrack_dir dir, 207 struct flow_action *action) 208 { 209 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple; 210 struct nf_conntrack_tuple target; 211 212 if (!(ct->status & IPS_NAT_MASK)) 213 return 0; 214 215 nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple); 216 217 switch (tuple->src.l3num) { 218 case NFPROTO_IPV4: 219 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target, 220 action); 221 break; 222 case NFPROTO_IPV6: 223 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target, 224 action); 225 break; 226 default: 227 return -EOPNOTSUPP; 228 } 229 230 switch (nf_ct_protonum(ct)) { 231 case IPPROTO_TCP: 232 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action); 233 break; 234 case IPPROTO_UDP: 235 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action); 236 break; 237 default: 238 return -EOPNOTSUPP; 239 } 240 241 return 0; 242 } 243 244 static int tcf_ct_flow_table_fill_actions(struct net *net, 245 struct flow_offload *flow, 246 enum flow_offload_tuple_dir tdir, 247 struct nf_flow_rule *flow_rule) 248 { 249 struct flow_action *action = &flow_rule->rule->action; 250 int num_entries = action->num_entries; 251 struct nf_conn *ct = flow->ct; 252 enum ip_conntrack_info ctinfo; 253 enum ip_conntrack_dir dir; 254 int i, err; 255 256 switch (tdir) { 257 case FLOW_OFFLOAD_DIR_ORIGINAL: 258 dir = IP_CT_DIR_ORIGINAL; 259 ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ? 260 IP_CT_ESTABLISHED : IP_CT_NEW; 261 if (ctinfo == IP_CT_ESTABLISHED) 262 set_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags); 263 break; 264 case FLOW_OFFLOAD_DIR_REPLY: 265 dir = IP_CT_DIR_REPLY; 266 ctinfo = IP_CT_ESTABLISHED_REPLY; 267 break; 268 default: 269 return -EOPNOTSUPP; 270 } 271 272 err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action); 273 if (err) 274 goto err_nat; 275 276 tcf_ct_flow_table_add_action_meta(ct, dir, ctinfo, action); 277 return 0; 278 279 err_nat: 280 /* Clear filled actions */ 281 for (i = num_entries; i < action->num_entries; i++) 282 memset(&action->entries[i], 0, sizeof(action->entries[i])); 283 action->num_entries = num_entries; 284 285 return err; 286 } 287 288 static bool tcf_ct_flow_is_outdated(const struct flow_offload *flow) 289 { 290 return test_bit(IPS_SEEN_REPLY_BIT, &flow->ct->status) && 291 test_bit(IPS_HW_OFFLOAD_BIT, &flow->ct->status) && 292 !test_bit(NF_FLOW_HW_PENDING, &flow->flags) && 293 !test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags); 294 } 295 296 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft); 297 298 static void tcf_ct_nf_get(struct nf_flowtable *ft) 299 { 300 struct tcf_ct_flow_table *ct_ft = 301 container_of(ft, struct tcf_ct_flow_table, nf_ft); 302 303 tcf_ct_flow_table_get_ref(ct_ft); 304 } 305 306 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft); 307 308 static void tcf_ct_nf_put(struct nf_flowtable *ft) 309 { 310 struct tcf_ct_flow_table *ct_ft = 311 container_of(ft, struct tcf_ct_flow_table, nf_ft); 312 313 tcf_ct_flow_table_put(ct_ft); 314 } 315 316 static struct nf_flowtable_type flowtable_ct = { 317 .gc = tcf_ct_flow_is_outdated, 318 .action = tcf_ct_flow_table_fill_actions, 319 .get = tcf_ct_nf_get, 320 .put = tcf_ct_nf_put, 321 .owner = THIS_MODULE, 322 }; 323 324 static int tcf_ct_flow_table_get(struct net *net, struct tcf_ct_params *params) 325 { 326 struct zones_ht_key key = { .net = net, .zone = params->zone }; 327 struct tcf_ct_flow_table *ct_ft; 328 int err = -ENOMEM; 329 330 mutex_lock(&zones_mutex); 331 rcu_read_lock(); 332 ct_ft = rhashtable_lookup(&zones_ht, &key, zones_params); 333 if (ct_ft && refcount_inc_not_zero(&ct_ft->ref)) { 334 rcu_read_unlock(); 335 goto out_unlock; 336 } 337 rcu_read_unlock(); 338 339 ct_ft = kzalloc_obj(*ct_ft); 340 if (!ct_ft) 341 goto err_alloc; 342 refcount_set(&ct_ft->ref, 1); 343 344 ct_ft->key = key; 345 err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params); 346 if (err) 347 goto err_insert; 348 349 ct_ft->nf_ft.type = &flowtable_ct; 350 ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD | 351 NF_FLOWTABLE_COUNTER; 352 err = nf_flow_table_init(&ct_ft->nf_ft); 353 if (err) 354 goto err_init; 355 write_pnet(&ct_ft->nf_ft.net, net); 356 357 __module_get(THIS_MODULE); 358 out_unlock: 359 params->ct_ft = ct_ft; 360 params->nf_ft = &ct_ft->nf_ft; 361 mutex_unlock(&zones_mutex); 362 363 return 0; 364 365 err_init: 366 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 367 err_insert: 368 kfree(ct_ft); 369 err_alloc: 370 mutex_unlock(&zones_mutex); 371 return err; 372 } 373 374 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft) 375 { 376 refcount_inc(&ct_ft->ref); 377 } 378 379 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work) 380 { 381 struct tcf_ct_flow_table *ct_ft; 382 struct flow_block *block; 383 384 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table, 385 rwork); 386 nf_flow_table_free(&ct_ft->nf_ft); 387 388 block = &ct_ft->nf_ft.flow_block; 389 down_write(&ct_ft->nf_ft.flow_block_lock); 390 WARN_ON(!list_empty(&block->cb_list)); 391 up_write(&ct_ft->nf_ft.flow_block_lock); 392 kfree(ct_ft); 393 394 module_put(THIS_MODULE); 395 } 396 397 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft) 398 { 399 if (refcount_dec_and_test(&ct_ft->ref)) { 400 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params); 401 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work); 402 queue_rcu_work(act_ct_wq, &ct_ft->rwork); 403 } 404 } 405 406 static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry, 407 struct nf_conn_act_ct_ext *act_ct_ext, u8 dir) 408 { 409 entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC; 410 entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir]; 411 } 412 413 static void tcf_ct_flow_ct_ext_ifidx_update(struct flow_offload *entry) 414 { 415 struct nf_conn_act_ct_ext *act_ct_ext; 416 417 act_ct_ext = nf_conn_act_ct_ext_find(entry->ct); 418 if (act_ct_ext) { 419 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL); 420 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY); 421 } 422 } 423 424 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft, 425 struct nf_conn *ct, 426 bool tcp, bool bidirectional) 427 { 428 struct nf_conn_act_ct_ext *act_ct_ext; 429 struct flow_offload *entry; 430 int err; 431 432 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status)) 433 return; 434 435 /* NULL if ct is dying (raced flush) or the atomic alloc failed. */ 436 entry = flow_offload_alloc(ct); 437 if (!entry) 438 goto err_alloc; 439 440 if (tcp) { 441 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 442 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL; 443 } 444 if (bidirectional) 445 __set_bit(NF_FLOW_HW_BIDIRECTIONAL, &entry->flags); 446 447 act_ct_ext = nf_conn_act_ct_ext_find(ct); 448 if (act_ct_ext) { 449 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL); 450 tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY); 451 } 452 453 err = flow_offload_add(&ct_ft->nf_ft, entry); 454 if (err) 455 goto err_add; 456 457 return; 458 459 err_add: 460 flow_offload_free(entry); 461 err_alloc: 462 clear_bit(IPS_OFFLOAD_BIT, &ct->status); 463 } 464 465 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft, 466 struct nf_conn *ct, 467 enum ip_conntrack_info ctinfo) 468 { 469 bool tcp = false, bidirectional = true; 470 471 switch (nf_ct_protonum(ct)) { 472 case IPPROTO_TCP: 473 if ((ctinfo != IP_CT_ESTABLISHED && 474 ctinfo != IP_CT_ESTABLISHED_REPLY) || 475 !test_bit(IPS_ASSURED_BIT, &ct->status) || 476 ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED) 477 return; 478 479 tcp = true; 480 break; 481 case IPPROTO_UDP: 482 if (!nf_ct_is_confirmed(ct)) 483 return; 484 if (!test_bit(IPS_ASSURED_BIT, &ct->status)) 485 bidirectional = false; 486 break; 487 #ifdef CONFIG_NF_CT_PROTO_GRE 488 case IPPROTO_GRE: { 489 struct nf_conntrack_tuple *tuple; 490 491 if ((ctinfo != IP_CT_ESTABLISHED && 492 ctinfo != IP_CT_ESTABLISHED_REPLY) || 493 !test_bit(IPS_ASSURED_BIT, &ct->status) || 494 ct->status & IPS_NAT_MASK) 495 return; 496 497 tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple; 498 /* No support for GRE v1 */ 499 if (tuple->src.u.gre.key || tuple->dst.u.gre.key) 500 return; 501 break; 502 } 503 #endif 504 default: 505 return; 506 } 507 508 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) || 509 ct->status & IPS_SEQ_ADJUST) 510 return; 511 512 tcf_ct_flow_table_add(ct_ft, ct, tcp, bidirectional); 513 } 514 515 static bool 516 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb, 517 struct flow_offload_tuple *tuple, 518 struct tcphdr **tcph) 519 { 520 struct flow_ports *ports; 521 unsigned int thoff; 522 struct iphdr *iph; 523 size_t hdrsize; 524 u8 ipproto; 525 526 if (!pskb_network_may_pull(skb, sizeof(*iph))) 527 return false; 528 529 iph = ip_hdr(skb); 530 thoff = iph->ihl * 4; 531 532 if (ip_is_fragment(iph) || 533 unlikely(thoff != sizeof(struct iphdr))) 534 return false; 535 536 ipproto = iph->protocol; 537 switch (ipproto) { 538 case IPPROTO_TCP: 539 hdrsize = sizeof(struct tcphdr); 540 break; 541 case IPPROTO_UDP: 542 hdrsize = sizeof(*ports); 543 break; 544 #ifdef CONFIG_NF_CT_PROTO_GRE 545 case IPPROTO_GRE: 546 hdrsize = sizeof(struct gre_base_hdr); 547 break; 548 #endif 549 default: 550 return false; 551 } 552 553 if (iph->ttl <= 1) 554 return false; 555 556 if (!pskb_network_may_pull(skb, thoff + hdrsize)) 557 return false; 558 559 switch (ipproto) { 560 case IPPROTO_TCP: 561 *tcph = (void *)(skb_network_header(skb) + thoff); 562 fallthrough; 563 case IPPROTO_UDP: 564 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 565 tuple->src_port = ports->source; 566 tuple->dst_port = ports->dest; 567 break; 568 case IPPROTO_GRE: { 569 struct gre_base_hdr *greh; 570 571 greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff); 572 if ((greh->flags & GRE_VERSION) != GRE_VERSION_0) 573 return false; 574 break; 575 } 576 } 577 578 iph = ip_hdr(skb); 579 580 tuple->src_v4.s_addr = iph->saddr; 581 tuple->dst_v4.s_addr = iph->daddr; 582 tuple->l3proto = AF_INET; 583 tuple->l4proto = ipproto; 584 585 return true; 586 } 587 588 static bool 589 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb, 590 struct flow_offload_tuple *tuple, 591 struct tcphdr **tcph) 592 { 593 struct flow_ports *ports; 594 struct ipv6hdr *ip6h; 595 unsigned int thoff; 596 size_t hdrsize; 597 u8 nexthdr; 598 599 if (!pskb_network_may_pull(skb, sizeof(*ip6h))) 600 return false; 601 602 ip6h = ipv6_hdr(skb); 603 thoff = sizeof(*ip6h); 604 605 nexthdr = ip6h->nexthdr; 606 switch (nexthdr) { 607 case IPPROTO_TCP: 608 hdrsize = sizeof(struct tcphdr); 609 break; 610 case IPPROTO_UDP: 611 hdrsize = sizeof(*ports); 612 break; 613 #ifdef CONFIG_NF_CT_PROTO_GRE 614 case IPPROTO_GRE: 615 hdrsize = sizeof(struct gre_base_hdr); 616 break; 617 #endif 618 default: 619 return false; 620 } 621 622 if (ip6h->hop_limit <= 1) 623 return false; 624 625 if (!pskb_network_may_pull(skb, thoff + hdrsize)) 626 return false; 627 628 switch (nexthdr) { 629 case IPPROTO_TCP: 630 *tcph = (void *)(skb_network_header(skb) + thoff); 631 fallthrough; 632 case IPPROTO_UDP: 633 ports = (struct flow_ports *)(skb_network_header(skb) + thoff); 634 tuple->src_port = ports->source; 635 tuple->dst_port = ports->dest; 636 break; 637 case IPPROTO_GRE: { 638 struct gre_base_hdr *greh; 639 640 greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff); 641 if ((greh->flags & GRE_VERSION) != GRE_VERSION_0) 642 return false; 643 break; 644 } 645 } 646 647 ip6h = ipv6_hdr(skb); 648 649 tuple->src_v6 = ip6h->saddr; 650 tuple->dst_v6 = ip6h->daddr; 651 tuple->l3proto = AF_INET6; 652 tuple->l4proto = nexthdr; 653 654 return true; 655 } 656 657 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p, 658 struct sk_buff *skb, 659 u8 family) 660 { 661 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft; 662 struct flow_offload_tuple_rhash *tuplehash; 663 struct flow_offload_tuple tuple = {}; 664 enum ip_conntrack_info ctinfo; 665 struct tcphdr *tcph = NULL; 666 bool force_refresh = false; 667 struct flow_offload *flow; 668 struct nf_conn *ct; 669 u8 dir; 670 671 switch (family) { 672 case NFPROTO_IPV4: 673 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph)) 674 return false; 675 break; 676 case NFPROTO_IPV6: 677 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph)) 678 return false; 679 break; 680 default: 681 return false; 682 } 683 684 tuplehash = flow_offload_lookup(nf_ft, &tuple); 685 if (!tuplehash) 686 return false; 687 688 dir = tuplehash->tuple.dir; 689 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]); 690 ct = flow->ct; 691 692 if (dir == FLOW_OFFLOAD_DIR_REPLY && 693 !test_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags)) { 694 /* Only offload reply direction after connection became 695 * assured. 696 */ 697 if (test_bit(IPS_ASSURED_BIT, &ct->status)) 698 set_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags); 699 else if (test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags)) 700 /* If flow_table flow has already been updated to the 701 * established state, then don't refresh. 702 */ 703 return false; 704 force_refresh = true; 705 } 706 707 if (tcph && (unlikely(tcph->fin || tcph->rst))) { 708 flow_offload_teardown(flow); 709 return false; 710 } 711 712 if (dir == FLOW_OFFLOAD_DIR_ORIGINAL) 713 ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ? 714 IP_CT_ESTABLISHED : IP_CT_NEW; 715 else 716 ctinfo = IP_CT_ESTABLISHED_REPLY; 717 718 nf_conn_act_ct_ext_fill(skb, ct, ctinfo); 719 tcf_ct_flow_ct_ext_ifidx_update(flow); 720 flow_offload_refresh(nf_ft, flow, force_refresh); 721 if (!test_bit(IPS_ASSURED_BIT, &ct->status)) { 722 /* Process this flow in SW to allow promoting to ASSURED */ 723 return false; 724 } 725 726 nf_conntrack_get(&ct->ct_general); 727 nf_ct_set(skb, ct, ctinfo); 728 if (nf_ft->flags & NF_FLOWTABLE_COUNTER) 729 nf_ct_acct_update(ct, dir, skb->len); 730 731 return true; 732 } 733 734 static int tcf_ct_flow_tables_init(void) 735 { 736 return rhashtable_init(&zones_ht, &zones_params); 737 } 738 739 static void tcf_ct_flow_tables_uninit(void) 740 { 741 rhashtable_destroy(&zones_ht); 742 } 743 744 static struct tc_action_ops act_ct_ops; 745 746 struct tc_ct_action_net { 747 struct tc_action_net tn; /* Must be first */ 748 }; 749 750 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ 751 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb, 752 struct tcf_ct_params *p) 753 { 754 enum ip_conntrack_info ctinfo; 755 struct nf_conn *ct; 756 757 ct = nf_ct_get(skb, &ctinfo); 758 if (!ct) 759 return false; 760 if (!net_eq(net, read_pnet(&ct->ct_net))) 761 goto drop_ct; 762 if (nf_ct_zone(ct)->id != p->zone) 763 goto drop_ct; 764 if (p->helper) { 765 struct nf_conn_help *help; 766 767 help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER); 768 if (help && rcu_access_pointer(help->helper) != p->helper) 769 goto drop_ct; 770 } 771 772 /* Force conntrack entry direction. */ 773 if ((p->ct_action & TCA_CT_ACT_FORCE) && 774 CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 775 if (nf_ct_is_confirmed(ct)) 776 nf_ct_kill(ct); 777 778 goto drop_ct; 779 } 780 781 return true; 782 783 drop_ct: 784 nf_reset_ct(skb); 785 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 786 787 return false; 788 } 789 790 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb) 791 { 792 u8 family = NFPROTO_UNSPEC; 793 794 switch (skb_protocol(skb, true)) { 795 case htons(ETH_P_IP): 796 family = NFPROTO_IPV4; 797 break; 798 case htons(ETH_P_IPV6): 799 family = NFPROTO_IPV6; 800 break; 801 default: 802 break; 803 } 804 805 return family; 806 } 807 808 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag) 809 { 810 unsigned int len; 811 812 len = skb_network_offset(skb) + sizeof(struct iphdr); 813 if (unlikely(skb->len < len)) 814 return -EINVAL; 815 if (unlikely(!pskb_may_pull(skb, len))) 816 return -ENOMEM; 817 818 *frag = ip_is_fragment(ip_hdr(skb)); 819 return 0; 820 } 821 822 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag) 823 { 824 unsigned int flags = 0, len, payload_ofs = 0; 825 unsigned short frag_off; 826 int nexthdr; 827 828 len = skb_network_offset(skb) + sizeof(struct ipv6hdr); 829 if (unlikely(skb->len < len)) 830 return -EINVAL; 831 if (unlikely(!pskb_may_pull(skb, len))) 832 return -ENOMEM; 833 834 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags); 835 if (unlikely(nexthdr < 0)) 836 return -EPROTO; 837 838 *frag = flags & IP6_FH_F_FRAG; 839 return 0; 840 } 841 842 /* On error, tells the caller whether it still owns @skb and must free it 843 * itself. @skb is ours only when the header checks below reject the packet 844 * before it is handed to the defragmentation engine; once nf_ct_handle_ 845 * fragments() has been called the skb is either queued (-EINPROGRESS) or has 846 * already been freed by it. 847 */ 848 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb, 849 u8 family, u16 zone, bool *defrag, 850 bool *skb_is_ours) 851 { 852 enum ip_conntrack_info ctinfo; 853 struct tc_skb_cb cb; 854 struct nf_conn *ct; 855 int err = 0; 856 bool frag; 857 u8 proto; 858 859 /* Previously seen (loopback)? Ignore. */ 860 ct = nf_ct_get(skb, &ctinfo); 861 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED) 862 return 0; 863 864 if (family == NFPROTO_IPV4) 865 err = tcf_ct_ipv4_is_fragment(skb, &frag); 866 else 867 err = tcf_ct_ipv6_is_fragment(skb, &frag); 868 if (err) { 869 *skb_is_ours = true; 870 return err; 871 } 872 if (!frag) 873 return 0; 874 875 cb = *tc_skb_cb(skb); 876 err = nf_ct_handle_fragments(net, skb, zone, family, &proto, &cb.mru); 877 if (err) 878 return err; 879 880 *defrag = true; 881 *tc_skb_cb(skb) = cb; 882 883 return 0; 884 } 885 886 static void tcf_ct_params_free(struct tcf_ct_params *params) 887 { 888 if (params->helper) { 889 #if IS_ENABLED(CONFIG_NF_NAT) 890 if (params->ct_action & TCA_CT_ACT_NAT) 891 nf_nat_helper_put(params->helper); 892 #endif 893 nf_conntrack_helper_put(params->helper); 894 } 895 if (params->ct_ft) 896 tcf_ct_flow_table_put(params->ct_ft); 897 if (params->tmpl) { 898 if (params->put_labels) 899 nf_connlabels_put(nf_ct_net(params->tmpl)); 900 901 nf_ct_put(params->tmpl); 902 } 903 904 kfree(params); 905 } 906 907 static void tcf_ct_params_free_rcu(struct rcu_head *head) 908 { 909 struct tcf_ct_params *params; 910 911 params = container_of(head, struct tcf_ct_params, rcu); 912 tcf_ct_params_free(params); 913 } 914 915 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask) 916 { 917 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 918 u32 new_mark; 919 920 if (!mask) 921 return; 922 923 new_mark = mark | (READ_ONCE(ct->mark) & ~(mask)); 924 if (READ_ONCE(ct->mark) != new_mark) { 925 WRITE_ONCE(ct->mark, new_mark); 926 if (nf_ct_is_confirmed(ct)) 927 nf_conntrack_event_cache(IPCT_MARK, ct); 928 } 929 #endif 930 } 931 932 static void tcf_ct_act_set_labels(struct nf_conn *ct, 933 u32 *labels, 934 u32 *labels_m) 935 { 936 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) 937 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels); 938 939 if (!memchr_inv(labels_m, 0, labels_sz)) 940 return; 941 942 nf_connlabels_replace(ct, labels, labels_m, 4); 943 #endif 944 } 945 946 static int tcf_ct_act_nat(struct sk_buff *skb, 947 struct nf_conn *ct, 948 enum ip_conntrack_info ctinfo, 949 int ct_action, 950 struct nf_nat_range2 *range, 951 bool commit) 952 { 953 #if IS_ENABLED(CONFIG_NF_NAT) 954 int err, action = 0; 955 956 if (!(ct_action & TCA_CT_ACT_NAT)) 957 return NF_ACCEPT; 958 if (ct_action & TCA_CT_ACT_NAT_SRC) 959 action |= BIT(NF_NAT_MANIP_SRC); 960 if (ct_action & TCA_CT_ACT_NAT_DST) 961 action |= BIT(NF_NAT_MANIP_DST); 962 963 err = nf_ct_nat(skb, ct, ctinfo, &action, range, commit); 964 if (err != NF_ACCEPT) 965 return err & NF_VERDICT_MASK; 966 967 if (action & BIT(NF_NAT_MANIP_SRC)) 968 qdisc_skb_cb(skb)->post_ct_snat = 1; 969 if (action & BIT(NF_NAT_MANIP_DST)) 970 qdisc_skb_cb(skb)->post_ct_dnat = 1; 971 972 return err; 973 #else 974 return NF_ACCEPT; 975 #endif 976 } 977 978 TC_INDIRECT_SCOPE int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a, 979 struct tcf_result *res) 980 { 981 struct net *net = dev_net(skb->dev); 982 enum ip_conntrack_info ctinfo; 983 struct tcf_ct *c = to_ct(a); 984 struct nf_conn *tmpl = NULL; 985 struct nf_hook_state state; 986 bool cached, commit, clear; 987 int nh_ofs, err, retval; 988 struct tcf_ct_params *p; 989 bool add_helper = false; 990 bool skb_is_ours = false; 991 bool skip_add = false; 992 bool defrag = false; 993 struct nf_conn *ct; 994 u8 family; 995 996 p = rcu_dereference_bh(c->params); 997 998 retval = p->action; 999 commit = p->ct_action & TCA_CT_ACT_COMMIT; 1000 clear = p->ct_action & TCA_CT_ACT_CLEAR; 1001 tmpl = p->tmpl; 1002 1003 tcf_lastuse_update(&c->tcf_tm); 1004 tcf_action_update_bstats(&c->common, skb); 1005 1006 if (clear) { 1007 qdisc_skb_cb(skb)->post_ct = false; 1008 ct = nf_ct_get(skb, &ctinfo); 1009 if (ct) { 1010 nf_reset_ct(skb); 1011 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 1012 } 1013 1014 goto out_clear; 1015 } 1016 1017 family = tcf_ct_skb_nf_family(skb); 1018 if (family == NFPROTO_UNSPEC) 1019 goto drop; 1020 1021 /* The conntrack module expects to be working at L3. 1022 * We also try to pull the IPv4/6 header to linear area 1023 */ 1024 nh_ofs = skb_network_offset(skb); 1025 skb_pull_rcsum(skb, nh_ofs); 1026 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag, 1027 &skb_is_ours); 1028 if (err) { 1029 /* The skb is still ours only when the header checks rejected 1030 * it; returning TC_ACT_CONSUMED for such a packet would leak 1031 * it, since no caller frees an skb it was told it no longer 1032 * owns. 1033 */ 1034 if (skb_is_ours) 1035 goto drop; 1036 goto out_frag; 1037 } 1038 1039 err = nf_ct_skb_network_trim(skb, family); 1040 if (err) 1041 goto drop; 1042 1043 /* If we are recirculating packets to match on ct fields and 1044 * committing with a separate ct action, then we don't need to 1045 * actually run the packet through conntrack twice unless it's for a 1046 * different zone. 1047 */ 1048 cached = tcf_ct_skb_nfct_cached(net, skb, p); 1049 if (!cached) { 1050 if (tcf_ct_flow_table_lookup(p, skb, family)) { 1051 skip_add = true; 1052 goto do_nat; 1053 } 1054 1055 /* Associate skb with specified zone. */ 1056 if (tmpl) { 1057 nf_reset_ct(skb); 1058 nf_conntrack_get(&tmpl->ct_general); 1059 nf_ct_set(skb, tmpl, IP_CT_NEW); 1060 } 1061 1062 state.hook = NF_INET_PRE_ROUTING; 1063 state.net = net; 1064 state.pf = family; 1065 err = nf_conntrack_in(skb, &state); 1066 if (err != NF_ACCEPT) 1067 goto nf_error; 1068 } 1069 1070 do_nat: 1071 ct = nf_ct_get(skb, &ctinfo); 1072 if (!ct) 1073 goto out_push; 1074 nf_ct_deliver_cached_events(ct); 1075 nf_conn_act_ct_ext_fill(skb, ct, ctinfo); 1076 1077 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit); 1078 if (err != NF_ACCEPT) 1079 goto nf_error; 1080 1081 if (!nf_ct_is_confirmed(ct) && commit && p->helper && !nfct_help(ct)) { 1082 err = __nf_ct_try_assign_helper(ct, p->tmpl, GFP_ATOMIC); 1083 if (err) 1084 goto drop; 1085 add_helper = true; 1086 if (p->ct_action & TCA_CT_ACT_NAT && !nfct_seqadj(ct)) { 1087 if (!nfct_seqadj_ext_add(ct)) 1088 goto drop; 1089 } 1090 } 1091 1092 if (nf_ct_is_confirmed(ct) ? ((!cached && !skip_add) || add_helper) : commit) { 1093 err = nf_ct_helper(skb, ct, ctinfo, family); 1094 if (err != NF_ACCEPT) 1095 goto nf_error; 1096 } 1097 1098 if (commit) { 1099 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask); 1100 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask); 1101 1102 if (!nf_ct_is_confirmed(ct)) 1103 nf_conn_act_ct_ext_add(skb, ct, ctinfo); 1104 1105 /* This will take care of sending queued events 1106 * even if the connection is already confirmed. 1107 */ 1108 err = nf_conntrack_confirm(skb); 1109 if (err != NF_ACCEPT) 1110 goto nf_error; 1111 1112 /* The ct may be dropped if a clash has been resolved, 1113 * so it's necessary to retrieve it from skb again to 1114 * prevent UAF. 1115 */ 1116 ct = nf_ct_get(skb, &ctinfo); 1117 if (!ct) 1118 skip_add = true; 1119 } 1120 1121 if (!skip_add) 1122 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo); 1123 1124 out_push: 1125 skb_push_rcsum(skb, nh_ofs); 1126 1127 qdisc_skb_cb(skb)->post_ct = true; 1128 tc_skb_cb(skb)->zone = p->zone; 1129 out_clear: 1130 if (defrag) 1131 qdisc_skb_cb(skb)->pkt_len = skb->len; 1132 return retval; 1133 1134 out_frag: 1135 if (err != -EINPROGRESS) 1136 tcf_action_inc_drop_qstats(&c->common); 1137 return TC_ACT_CONSUMED; 1138 1139 drop: 1140 tcf_action_inc_drop_qstats(&c->common); 1141 return TC_ACT_SHOT; 1142 1143 nf_error: 1144 /* some verdicts store extra data in upper bits, such 1145 * as errno or queue number. 1146 */ 1147 switch (err & NF_VERDICT_MASK) { 1148 case NF_DROP: 1149 goto drop; 1150 case NF_STOLEN: 1151 tcf_action_inc_drop_qstats(&c->common); 1152 return TC_ACT_CONSUMED; 1153 default: 1154 DEBUG_NET_WARN_ON_ONCE(1); 1155 goto drop; 1156 } 1157 } 1158 1159 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = { 1160 [TCA_CT_ACTION] = { .type = NLA_U16 }, 1161 [TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)), 1162 [TCA_CT_ZONE] = { .type = NLA_U16 }, 1163 [TCA_CT_MARK] = { .type = NLA_U32 }, 1164 [TCA_CT_MARK_MASK] = { .type = NLA_U32 }, 1165 [TCA_CT_LABELS] = { .type = NLA_BINARY, 1166 .len = 128 / BITS_PER_BYTE }, 1167 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY, 1168 .len = 128 / BITS_PER_BYTE }, 1169 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 }, 1170 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 }, 1171 [TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1172 [TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)), 1173 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 }, 1174 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 }, 1175 [TCA_CT_HELPER_NAME] = { .type = NLA_STRING, .len = NF_CT_HELPER_NAME_LEN }, 1176 [TCA_CT_HELPER_FAMILY] = { .type = NLA_U8 }, 1177 [TCA_CT_HELPER_PROTO] = { .type = NLA_U8 }, 1178 }; 1179 1180 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p, 1181 struct tc_ct *parm, 1182 struct nlattr **tb, 1183 struct netlink_ext_ack *extack) 1184 { 1185 struct nf_nat_range2 *range; 1186 1187 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1188 return 0; 1189 1190 if (!IS_ENABLED(CONFIG_NF_NAT)) { 1191 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel"); 1192 return -EOPNOTSUPP; 1193 } 1194 1195 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1196 return 0; 1197 1198 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) && 1199 (p->ct_action & TCA_CT_ACT_NAT_DST)) { 1200 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time"); 1201 return -EOPNOTSUPP; 1202 } 1203 1204 range = &p->range; 1205 if (tb[TCA_CT_NAT_IPV4_MIN]) { 1206 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX]; 1207 1208 p->ipv4_range = true; 1209 range->flags |= NF_NAT_RANGE_MAP_IPS; 1210 range->min_addr.ip = 1211 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]); 1212 1213 range->max_addr.ip = 1214 nla_get_in_addr_default(max_attr, range->min_addr.ip); 1215 } else if (tb[TCA_CT_NAT_IPV6_MIN]) { 1216 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX]; 1217 1218 p->ipv4_range = false; 1219 range->flags |= NF_NAT_RANGE_MAP_IPS; 1220 range->min_addr.in6 = 1221 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]); 1222 1223 range->max_addr.in6 = max_attr ? 1224 nla_get_in6_addr(max_attr) : 1225 range->min_addr.in6; 1226 } 1227 1228 if (tb[TCA_CT_NAT_PORT_MIN]) { 1229 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1230 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]); 1231 1232 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ? 1233 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) : 1234 range->min_proto.all; 1235 } 1236 1237 return 0; 1238 } 1239 1240 static void tcf_ct_set_key_val(struct nlattr **tb, 1241 void *val, int val_type, 1242 void *mask, int mask_type, 1243 int len) 1244 { 1245 if (!tb[val_type]) 1246 return; 1247 nla_memcpy(val, tb[val_type], len); 1248 1249 if (!mask) 1250 return; 1251 1252 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type]) 1253 memset(mask, 0xff, len); 1254 else 1255 nla_memcpy(mask, tb[mask_type], len); 1256 } 1257 1258 static int tcf_ct_fill_params(struct net *net, 1259 struct tcf_ct_params *p, 1260 struct tc_ct *parm, 1261 struct nlattr **tb, 1262 struct netlink_ext_ack *extack) 1263 { 1264 struct nf_conntrack_zone zone; 1265 int err, family, proto, len; 1266 bool put_labels = false; 1267 struct nf_conn *tmpl; 1268 char *name; 1269 1270 p->zone = NF_CT_DEFAULT_ZONE_ID; 1271 1272 tcf_ct_set_key_val(tb, 1273 &p->ct_action, TCA_CT_ACTION, 1274 NULL, TCA_CT_UNSPEC, 1275 sizeof(p->ct_action)); 1276 1277 if (p->ct_action & TCA_CT_ACT_CLEAR) 1278 return 0; 1279 1280 err = tcf_ct_fill_params_nat(p, parm, tb, extack); 1281 if (err) 1282 return err; 1283 1284 if (tb[TCA_CT_MARK]) { 1285 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) { 1286 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled."); 1287 return -EOPNOTSUPP; 1288 } 1289 tcf_ct_set_key_val(tb, 1290 &p->mark, TCA_CT_MARK, 1291 &p->mark_mask, TCA_CT_MARK_MASK, 1292 sizeof(p->mark)); 1293 } 1294 1295 if (tb[TCA_CT_LABELS]) { 1296 unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8; 1297 1298 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) { 1299 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled."); 1300 return -EOPNOTSUPP; 1301 } 1302 1303 if (nf_connlabels_get(net, n_bits - 1)) { 1304 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length"); 1305 return -EOPNOTSUPP; 1306 } else { 1307 put_labels = true; 1308 } 1309 1310 tcf_ct_set_key_val(tb, 1311 p->labels, TCA_CT_LABELS, 1312 p->labels_mask, TCA_CT_LABELS_MASK, 1313 sizeof(p->labels)); 1314 } 1315 1316 if (tb[TCA_CT_ZONE]) { 1317 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) { 1318 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled."); 1319 err = -EOPNOTSUPP; 1320 goto err; 1321 } 1322 1323 tcf_ct_set_key_val(tb, 1324 &p->zone, TCA_CT_ZONE, 1325 NULL, TCA_CT_UNSPEC, 1326 sizeof(p->zone)); 1327 } 1328 1329 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0); 1330 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL); 1331 if (!tmpl) { 1332 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template"); 1333 err = -ENOMEM; 1334 goto err; 1335 } 1336 p->tmpl = tmpl; 1337 if (tb[TCA_CT_HELPER_NAME]) { 1338 name = nla_data(tb[TCA_CT_HELPER_NAME]); 1339 len = nla_len(tb[TCA_CT_HELPER_NAME]); 1340 if (len > 16 || name[len - 1] != '\0') { 1341 NL_SET_ERR_MSG_MOD(extack, "Failed to parse helper name."); 1342 err = -EINVAL; 1343 goto err; 1344 } 1345 family = nla_get_u8_default(tb[TCA_CT_HELPER_FAMILY], AF_INET); 1346 proto = nla_get_u8_default(tb[TCA_CT_HELPER_PROTO], 1347 IPPROTO_TCP); 1348 err = nf_ct_add_helper(tmpl, name, family, proto, 1349 p->ct_action & TCA_CT_ACT_NAT, &p->helper); 1350 if (err) { 1351 NL_SET_ERR_MSG_MOD(extack, "Failed to add helper"); 1352 goto err; 1353 } 1354 } 1355 1356 p->put_labels = put_labels; 1357 1358 if (p->ct_action & TCA_CT_ACT_COMMIT) 1359 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status); 1360 return 0; 1361 err: 1362 if (put_labels) 1363 nf_connlabels_put(net); 1364 1365 nf_ct_put(p->tmpl); 1366 p->tmpl = NULL; 1367 return err; 1368 } 1369 1370 static int tcf_ct_init(struct net *net, struct nlattr *nla, 1371 struct nlattr *est, struct tc_action **a, 1372 struct tcf_proto *tp, u32 flags, 1373 struct netlink_ext_ack *extack) 1374 { 1375 struct tc_action_net *tn = net_generic(net, act_ct_ops.net_id); 1376 bool bind = flags & TCA_ACT_FLAGS_BIND; 1377 struct tcf_ct_params *params = NULL; 1378 struct nlattr *tb[TCA_CT_MAX + 1]; 1379 struct tcf_chain *goto_ch = NULL; 1380 struct tc_ct *parm; 1381 struct tcf_ct *c; 1382 int err, res = 0; 1383 u32 index; 1384 1385 if (!nla) { 1386 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed"); 1387 return -EINVAL; 1388 } 1389 1390 if (bind && !(flags & TCA_ACT_FLAGS_AT_INGRESS_OR_CLSACT)) { 1391 NL_SET_ERR_MSG_MOD(extack, 1392 "Attaching ct to a non ingress/clsact qdisc is unsupported"); 1393 return -EOPNOTSUPP; 1394 } 1395 1396 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack); 1397 if (err < 0) 1398 return err; 1399 1400 if (!tb[TCA_CT_PARMS]) { 1401 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters"); 1402 return -EINVAL; 1403 } 1404 parm = nla_data(tb[TCA_CT_PARMS]); 1405 index = parm->index; 1406 err = tcf_idr_check_alloc(tn, &index, a, bind); 1407 if (err < 0) 1408 return err; 1409 1410 if (!err) { 1411 err = tcf_idr_create_from_flags(tn, index, est, a, 1412 &act_ct_ops, bind, flags); 1413 if (err) { 1414 tcf_idr_cleanup(tn, index); 1415 return err; 1416 } 1417 res = ACT_P_CREATED; 1418 } else { 1419 if (bind) 1420 return ACT_P_BOUND; 1421 1422 if (!(flags & TCA_ACT_FLAGS_REPLACE)) { 1423 tcf_idr_release(*a, bind); 1424 return -EEXIST; 1425 } 1426 } 1427 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack); 1428 if (err < 0) 1429 goto cleanup; 1430 1431 c = to_ct(*a); 1432 1433 params = kzalloc_obj(*params); 1434 if (unlikely(!params)) { 1435 err = -ENOMEM; 1436 goto cleanup; 1437 } 1438 1439 err = tcf_ct_fill_params(net, params, parm, tb, extack); 1440 if (err) 1441 goto cleanup; 1442 1443 err = tcf_ct_flow_table_get(net, params); 1444 if (err) 1445 goto cleanup; 1446 1447 params->action = parm->action; 1448 spin_lock_bh(&c->tcf_lock); 1449 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch); 1450 params = rcu_replace_pointer(c->params, params, 1451 lockdep_is_held(&c->tcf_lock)); 1452 spin_unlock_bh(&c->tcf_lock); 1453 1454 if (goto_ch) 1455 tcf_chain_put_by_act(goto_ch); 1456 if (params) 1457 call_rcu(¶ms->rcu, tcf_ct_params_free_rcu); 1458 1459 return res; 1460 1461 cleanup: 1462 if (goto_ch) 1463 tcf_chain_put_by_act(goto_ch); 1464 if (params) 1465 tcf_ct_params_free(params); 1466 tcf_idr_release(*a, bind); 1467 return err; 1468 } 1469 1470 static void tcf_ct_cleanup(struct tc_action *a) 1471 { 1472 struct tcf_ct_params *params; 1473 struct tcf_ct *c = to_ct(a); 1474 1475 params = rcu_dereference_protected(c->params, 1); 1476 if (params) 1477 call_rcu(¶ms->rcu, tcf_ct_params_free_rcu); 1478 } 1479 1480 static int tcf_ct_dump_key_val(struct sk_buff *skb, 1481 const void *val, int val_type, 1482 const void *mask, int mask_type, 1483 int len) 1484 { 1485 int err; 1486 1487 if (mask && !memchr_inv(mask, 0, len)) 1488 return 0; 1489 1490 err = nla_put(skb, val_type, len, val); 1491 if (err) 1492 return err; 1493 1494 if (mask_type != TCA_CT_UNSPEC) { 1495 err = nla_put(skb, mask_type, len, mask); 1496 if (err) 1497 return err; 1498 } 1499 1500 return 0; 1501 } 1502 1503 static int tcf_ct_dump_nat(struct sk_buff *skb, const struct tcf_ct_params *p) 1504 { 1505 const struct nf_nat_range2 *range = &p->range; 1506 1507 if (!(p->ct_action & TCA_CT_ACT_NAT)) 1508 return 0; 1509 1510 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST))) 1511 return 0; 1512 1513 if (range->flags & NF_NAT_RANGE_MAP_IPS) { 1514 if (p->ipv4_range) { 1515 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN, 1516 range->min_addr.ip)) 1517 return -1; 1518 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX, 1519 range->max_addr.ip)) 1520 return -1; 1521 } else { 1522 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN, 1523 &range->min_addr.in6)) 1524 return -1; 1525 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX, 1526 &range->max_addr.in6)) 1527 return -1; 1528 } 1529 } 1530 1531 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) { 1532 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN, 1533 range->min_proto.all)) 1534 return -1; 1535 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX, 1536 range->max_proto.all)) 1537 return -1; 1538 } 1539 1540 return 0; 1541 } 1542 1543 static int tcf_ct_dump_helper(struct sk_buff *skb, 1544 const struct nf_conntrack_helper *helper) 1545 { 1546 if (!helper) 1547 return 0; 1548 1549 if (nla_put_string(skb, TCA_CT_HELPER_NAME, helper->name) || 1550 nla_put_u8(skb, TCA_CT_HELPER_FAMILY, helper->nfproto) || 1551 nla_put_u8(skb, TCA_CT_HELPER_PROTO, helper->l4proto)) 1552 return -1; 1553 1554 return 0; 1555 } 1556 1557 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a, 1558 int bind, int ref) 1559 { 1560 unsigned char *b = skb_tail_pointer(skb); 1561 const struct tcf_ct *c = to_ct(a); 1562 const struct tcf_ct_params *p; 1563 struct tc_ct opt = { 1564 .index = c->tcf_index, 1565 .refcnt = refcount_read(&c->tcf_refcnt) - ref, 1566 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind, 1567 }; 1568 struct tcf_t t; 1569 1570 rcu_read_lock(); 1571 p = rcu_dereference(c->params); 1572 opt.action = p->action; 1573 1574 if (tcf_ct_dump_key_val(skb, 1575 &p->ct_action, TCA_CT_ACTION, 1576 NULL, TCA_CT_UNSPEC, 1577 sizeof(p->ct_action))) 1578 goto nla_put_failure; 1579 1580 if (p->ct_action & TCA_CT_ACT_CLEAR) 1581 goto skip_dump; 1582 1583 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1584 tcf_ct_dump_key_val(skb, 1585 &p->mark, TCA_CT_MARK, 1586 &p->mark_mask, TCA_CT_MARK_MASK, 1587 sizeof(p->mark))) 1588 goto nla_put_failure; 1589 1590 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1591 tcf_ct_dump_key_val(skb, 1592 p->labels, TCA_CT_LABELS, 1593 p->labels_mask, TCA_CT_LABELS_MASK, 1594 sizeof(p->labels))) 1595 goto nla_put_failure; 1596 1597 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1598 tcf_ct_dump_key_val(skb, 1599 &p->zone, TCA_CT_ZONE, 1600 NULL, TCA_CT_UNSPEC, 1601 sizeof(p->zone))) 1602 goto nla_put_failure; 1603 1604 if (tcf_ct_dump_nat(skb, p)) 1605 goto nla_put_failure; 1606 1607 if (tcf_ct_dump_helper(skb, p->helper)) 1608 goto nla_put_failure; 1609 1610 skip_dump: 1611 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt)) 1612 goto nla_put_failure; 1613 1614 tcf_tm_dump(&t, &c->tcf_tm); 1615 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD)) 1616 goto nla_put_failure; 1617 rcu_read_unlock(); 1618 1619 return skb->len; 1620 nla_put_failure: 1621 rcu_read_unlock(); 1622 nlmsg_trim(skb, b); 1623 return -1; 1624 } 1625 1626 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets, 1627 u64 drops, u64 lastuse, bool hw) 1628 { 1629 struct tcf_ct *c = to_ct(a); 1630 1631 tcf_action_update_stats(a, bytes, packets, drops, hw); 1632 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse); 1633 } 1634 1635 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data, 1636 u32 *index_inc, bool bind, 1637 struct netlink_ext_ack *extack) 1638 { 1639 if (bind) { 1640 struct flow_action_entry *entry = entry_data; 1641 1642 if (tcf_ct_helper(act)) 1643 return -EOPNOTSUPP; 1644 1645 entry->id = FLOW_ACTION_CT; 1646 entry->ct.action = tcf_ct_action(act); 1647 entry->ct.zone = tcf_ct_zone(act); 1648 entry->ct.flow_table = tcf_ct_ft(act); 1649 *index_inc = 1; 1650 } else { 1651 struct flow_offload_action *fl_action = entry_data; 1652 1653 fl_action->id = FLOW_ACTION_CT; 1654 } 1655 1656 return 0; 1657 } 1658 1659 static size_t tcf_ct_get_fill_size(const struct tc_action *act) 1660 { 1661 const struct tcf_ct_params *p; 1662 size_t size; 1663 1664 size = nla_total_size(sizeof(struct tc_ct)) /* TCA_CT_PARMS */ 1665 + nla_total_size(sizeof(u16)); /* TCA_CT_ACTION */ 1666 1667 rcu_read_lock(); 1668 p = rcu_dereference(to_ct(act)->params); 1669 1670 if (p->ct_action & TCA_CT_ACT_CLEAR) 1671 goto out; 1672 1673 /* TCA_CT_MARK, TCA_CT_MARK_MASK */ 1674 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) 1675 size += nla_total_size(sizeof(p->mark)) 1676 + nla_total_size(sizeof(p->mark_mask)); 1677 1678 /* TCA_CT_LABELS, TCA_CT_LABELS_MASK */ 1679 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) 1680 size += nla_total_size(sizeof(p->labels)) 1681 + nla_total_size(sizeof(p->labels_mask)); 1682 1683 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) 1684 size += nla_total_size(sizeof(p->zone)); /* TCA_CT_ZONE */ 1685 1686 if (p->ct_action & TCA_CT_ACT_NAT) 1687 /* TCA_CT_NAT_IPV6_{MIN,MAX}, the larger of the two address 1688 * variants, plus TCA_CT_NAT_PORT_{MIN,MAX}. 1689 */ 1690 size += 2 * nla_total_size(sizeof(struct in6_addr)) 1691 + 2 * nla_total_size(sizeof(__be16)); 1692 1693 /* TCA_CT_HELPER_{NAME,FAMILY,PROTO} */ 1694 if (p->helper) 1695 size += nla_total_size(NF_CT_HELPER_NAME_LEN) 1696 + nla_total_size(sizeof(u8)) 1697 + nla_total_size(sizeof(u8)); 1698 out: 1699 rcu_read_unlock(); 1700 1701 return size; 1702 } 1703 1704 static struct tc_action_ops act_ct_ops = { 1705 .kind = "ct", 1706 .id = TCA_ID_CT, 1707 .owner = THIS_MODULE, 1708 .act = tcf_ct_act, 1709 .dump = tcf_ct_dump, 1710 .init = tcf_ct_init, 1711 .cleanup = tcf_ct_cleanup, 1712 .stats_update = tcf_stats_update, 1713 .get_fill_size = tcf_ct_get_fill_size, 1714 .offload_act_setup = tcf_ct_offload_act_setup, 1715 .size = sizeof(struct tcf_ct), 1716 }; 1717 MODULE_ALIAS_NET_ACT("ct"); 1718 1719 static __net_init int ct_init_net(struct net *net) 1720 { 1721 struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id); 1722 1723 return tc_action_net_init(net, &tn->tn, &act_ct_ops); 1724 } 1725 1726 static void __net_exit ct_exit_net(struct list_head *net_list) 1727 { 1728 tc_action_net_exit(net_list, act_ct_ops.net_id); 1729 } 1730 1731 static struct pernet_operations ct_net_ops = { 1732 .init = ct_init_net, 1733 .exit_batch = ct_exit_net, 1734 .id = &act_ct_ops.net_id, 1735 .size = sizeof(struct tc_ct_action_net), 1736 }; 1737 1738 static int __init ct_init_module(void) 1739 { 1740 int err; 1741 1742 act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0); 1743 if (!act_ct_wq) 1744 return -ENOMEM; 1745 1746 err = tcf_ct_flow_tables_init(); 1747 if (err) 1748 goto err_tbl_init; 1749 1750 err = tcf_register_action(&act_ct_ops, &ct_net_ops); 1751 if (err) 1752 goto err_register; 1753 1754 static_branch_inc(&tcf_frag_xmit_count); 1755 1756 return 0; 1757 1758 err_register: 1759 tcf_ct_flow_tables_uninit(); 1760 err_tbl_init: 1761 destroy_workqueue(act_ct_wq); 1762 return err; 1763 } 1764 1765 static void __exit ct_cleanup_module(void) 1766 { 1767 static_branch_dec(&tcf_frag_xmit_count); 1768 tcf_unregister_action(&act_ct_ops, &ct_net_ops); 1769 tcf_ct_flow_tables_uninit(); 1770 destroy_workqueue(act_ct_wq); 1771 } 1772 1773 module_init(ct_init_module); 1774 module_exit(ct_cleanup_module); 1775 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>"); 1776 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>"); 1777 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>"); 1778 MODULE_DESCRIPTION("Connection tracking action"); 1779 MODULE_LICENSE("GPL v2"); 1780