1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Copyright (c) 2015 Nicira, Inc. 4 */ 5 6#include <linux/module.h> 7#include <linux/openvswitch.h> 8#include <linux/tcp.h> 9#include <linux/udp.h> 10#include <linux/sctp.h> 11#include <linux/static_key.h> 12#include <net/ip.h> 13#include <net/genetlink.h> 14#include <net/netfilter/nf_conntrack_core.h> 15#include <net/netfilter/nf_conntrack_count.h> 16#include <net/netfilter/nf_conntrack_helper.h> 17#include <net/netfilter/nf_conntrack_labels.h> 18#include <net/netfilter/nf_conntrack_seqadj.h> 19#include <net/netfilter/nf_conntrack_timeout.h> 20#include <net/netfilter/nf_conntrack_zones.h> 21#include <net/netfilter/ipv6/nf_defrag_ipv6.h> 22#include <net/ipv6_frag.h> 23 24#if IS_ENABLED(CONFIG_NF_NAT) 25#include <net/netfilter/nf_nat.h> 26#endif 27 28#include "datapath.h" 29#include "conntrack.h" 30#include "flow.h" 31#include "flow_netlink.h" 32 33struct ovs_ct_len_tbl { 34 int maxlen; 35 int minlen; 36}; 37 38/* Metadata mark for masked write to conntrack mark */ 39struct md_mark { 40 u32 value; 41 u32 mask; 42}; 43 44/* Metadata label for masked write to conntrack label. */ 45struct md_labels { 46 struct ovs_key_ct_labels value; 47 struct ovs_key_ct_labels mask; 48}; 49 50enum ovs_ct_nat { 51 OVS_CT_NAT = 1 << 0, /* NAT for committed connections only. */ 52 OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */ 53 OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */ 54}; 55 56/* Conntrack action context for execution. */ 57struct ovs_conntrack_info { 58 struct nf_conntrack_helper *helper; 59 struct nf_conntrack_zone zone; 60 struct nf_conn *ct; 61 u8 commit : 1; 62 u8 nat : 3; /* enum ovs_ct_nat */ 63 u8 force : 1; 64 u8 have_eventmask : 1; 65 u16 family; 66 u32 eventmask; /* Mask of 1 << IPCT_*. */ 67 struct md_mark mark; 68 struct md_labels labels; 69 char timeout[CTNL_TIMEOUT_NAME_MAX]; 70 struct nf_ct_timeout *nf_ct_timeout; 71#if IS_ENABLED(CONFIG_NF_NAT) 72 struct nf_nat_range2 range; /* Only present for SRC NAT and DST NAT. */ 73#endif 74}; 75 76#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 77#define OVS_CT_LIMIT_UNLIMITED 0 78#define OVS_CT_LIMIT_DEFAULT OVS_CT_LIMIT_UNLIMITED 79#define CT_LIMIT_HASH_BUCKETS 512 80static DEFINE_STATIC_KEY_FALSE(ovs_ct_limit_enabled); 81 82struct ovs_ct_limit { 83 /* Elements in ovs_ct_limit_info->limits hash table */ 84 struct hlist_node hlist_node; 85 struct rcu_head rcu; 86 u16 zone; 87 u32 limit; 88}; 89 90struct ovs_ct_limit_info { 91 u32 default_limit; 92 struct hlist_head *limits; 93 struct nf_conncount_data *data; 94}; 95 96static const struct nla_policy ct_limit_policy[OVS_CT_LIMIT_ATTR_MAX + 1] = { 97 [OVS_CT_LIMIT_ATTR_ZONE_LIMIT] = { .type = NLA_NESTED, }, 98}; 99#endif 100 101static bool labels_nonzero(const struct ovs_key_ct_labels *labels); 102 103static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info); 104 105static u16 key_to_nfproto(const struct sw_flow_key *key) 106{ 107 switch (ntohs(key->eth.type)) { 108 case ETH_P_IP: 109 return NFPROTO_IPV4; 110 case ETH_P_IPV6: 111 return NFPROTO_IPV6; 112 default: 113 return NFPROTO_UNSPEC; 114 } 115} 116 117/* Map SKB connection state into the values used by flow definition. */ 118static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo) 119{ 120 u8 ct_state = OVS_CS_F_TRACKED; 121 122 switch (ctinfo) { 123 case IP_CT_ESTABLISHED_REPLY: 124 case IP_CT_RELATED_REPLY: 125 ct_state |= OVS_CS_F_REPLY_DIR; 126 break; 127 default: 128 break; 129 } 130 131 switch (ctinfo) { 132 case IP_CT_ESTABLISHED: 133 case IP_CT_ESTABLISHED_REPLY: 134 ct_state |= OVS_CS_F_ESTABLISHED; 135 break; 136 case IP_CT_RELATED: 137 case IP_CT_RELATED_REPLY: 138 ct_state |= OVS_CS_F_RELATED; 139 break; 140 case IP_CT_NEW: 141 ct_state |= OVS_CS_F_NEW; 142 break; 143 default: 144 break; 145 } 146 147 return ct_state; 148} 149 150static u32 ovs_ct_get_mark(const struct nf_conn *ct) 151{ 152#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 153 return ct ? READ_ONCE(ct->mark) : 0; 154#else 155 return 0; 156#endif 157} 158 159/* Guard against conntrack labels max size shrinking below 128 bits. */ 160#if NF_CT_LABELS_MAX_SIZE < 16 161#error NF_CT_LABELS_MAX_SIZE must be at least 16 bytes 162#endif 163 164static void ovs_ct_get_labels(const struct nf_conn *ct, 165 struct ovs_key_ct_labels *labels) 166{ 167 struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL; 168 169 if (cl) 170 memcpy(labels, cl->bits, OVS_CT_LABELS_LEN); 171 else 172 memset(labels, 0, OVS_CT_LABELS_LEN); 173} 174 175static void __ovs_ct_update_key_orig_tp(struct sw_flow_key *key, 176 const struct nf_conntrack_tuple *orig, 177 u8 icmp_proto) 178{ 179 key->ct_orig_proto = orig->dst.protonum; 180 if (orig->dst.protonum == icmp_proto) { 181 key->ct.orig_tp.src = htons(orig->dst.u.icmp.type); 182 key->ct.orig_tp.dst = htons(orig->dst.u.icmp.code); 183 } else { 184 key->ct.orig_tp.src = orig->src.u.all; 185 key->ct.orig_tp.dst = orig->dst.u.all; 186 } 187} 188 189static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state, 190 const struct nf_conntrack_zone *zone, 191 const struct nf_conn *ct) 192{ 193 key->ct_state = state; 194 key->ct_zone = zone->id; 195 key->ct.mark = ovs_ct_get_mark(ct); 196 ovs_ct_get_labels(ct, &key->ct.labels); 197 198 if (ct) { 199 const struct nf_conntrack_tuple *orig; 200 201 /* Use the master if we have one. */ 202 if (ct->master) 203 ct = ct->master; 204 orig = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple; 205 206 /* IP version must match with the master connection. */ 207 if (key->eth.type == htons(ETH_P_IP) && 208 nf_ct_l3num(ct) == NFPROTO_IPV4) { 209 key->ipv4.ct_orig.src = orig->src.u3.ip; 210 key->ipv4.ct_orig.dst = orig->dst.u3.ip; 211 __ovs_ct_update_key_orig_tp(key, orig, IPPROTO_ICMP); 212 return; 213 } else if (key->eth.type == htons(ETH_P_IPV6) && 214 !sw_flow_key_is_nd(key) && 215 nf_ct_l3num(ct) == NFPROTO_IPV6) { 216 key->ipv6.ct_orig.src = orig->src.u3.in6; 217 key->ipv6.ct_orig.dst = orig->dst.u3.in6; 218 __ovs_ct_update_key_orig_tp(key, orig, NEXTHDR_ICMP); 219 return; 220 } 221 } 222 /* Clear 'ct_orig_proto' to mark the non-existence of conntrack 223 * original direction key fields. 224 */ 225 key->ct_orig_proto = 0; 226} 227 228/* Update 'key' based on skb->_nfct. If 'post_ct' is true, then OVS has 229 * previously sent the packet to conntrack via the ct action. If 230 * 'keep_nat_flags' is true, the existing NAT flags retained, else they are 231 * initialized from the connection status. 232 */ 233static void ovs_ct_update_key(const struct sk_buff *skb, 234 const struct ovs_conntrack_info *info, 235 struct sw_flow_key *key, bool post_ct, 236 bool keep_nat_flags) 237{ 238 const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt; 239 enum ip_conntrack_info ctinfo; 240 struct nf_conn *ct; 241 u8 state = 0; 242 243 ct = nf_ct_get(skb, &ctinfo); 244 if (ct) { 245 state = ovs_ct_get_state(ctinfo); 246 /* All unconfirmed entries are NEW connections. */ 247 if (!nf_ct_is_confirmed(ct)) 248 state |= OVS_CS_F_NEW; 249 /* OVS persists the related flag for the duration of the 250 * connection. 251 */ 252 if (ct->master) 253 state |= OVS_CS_F_RELATED; 254 if (keep_nat_flags) { 255 state |= key->ct_state & OVS_CS_F_NAT_MASK; 256 } else { 257 if (ct->status & IPS_SRC_NAT) 258 state |= OVS_CS_F_SRC_NAT; 259 if (ct->status & IPS_DST_NAT) 260 state |= OVS_CS_F_DST_NAT; 261 } 262 zone = nf_ct_zone(ct); 263 } else if (post_ct) { 264 state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID; 265 if (info) 266 zone = &info->zone; 267 } 268 __ovs_ct_update_key(key, state, zone, ct); 269} 270 271/* This is called to initialize CT key fields possibly coming in from the local 272 * stack. 273 */ 274void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key) 275{ 276 ovs_ct_update_key(skb, NULL, key, false, false); 277} 278 279int ovs_ct_put_key(const struct sw_flow_key *swkey, 280 const struct sw_flow_key *output, struct sk_buff *skb) 281{ 282 if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, output->ct_state)) 283 return -EMSGSIZE; 284 285 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 286 nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, output->ct_zone)) 287 return -EMSGSIZE; 288 289 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 290 nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, output->ct.mark)) 291 return -EMSGSIZE; 292 293 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 294 nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(output->ct.labels), 295 &output->ct.labels)) 296 return -EMSGSIZE; 297 298 if (swkey->ct_orig_proto) { 299 if (swkey->eth.type == htons(ETH_P_IP)) { 300 struct ovs_key_ct_tuple_ipv4 orig; 301 302 memset(&orig, 0, sizeof(orig)); 303 orig.ipv4_src = output->ipv4.ct_orig.src; 304 orig.ipv4_dst = output->ipv4.ct_orig.dst; 305 orig.src_port = output->ct.orig_tp.src; 306 orig.dst_port = output->ct.orig_tp.dst; 307 orig.ipv4_proto = output->ct_orig_proto; 308 309 if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4, 310 sizeof(orig), &orig)) 311 return -EMSGSIZE; 312 } else if (swkey->eth.type == htons(ETH_P_IPV6)) { 313 struct ovs_key_ct_tuple_ipv6 orig; 314 315 memset(&orig, 0, sizeof(orig)); 316 memcpy(orig.ipv6_src, output->ipv6.ct_orig.src.s6_addr32, 317 sizeof(orig.ipv6_src)); 318 memcpy(orig.ipv6_dst, output->ipv6.ct_orig.dst.s6_addr32, 319 sizeof(orig.ipv6_dst)); 320 orig.src_port = output->ct.orig_tp.src; 321 orig.dst_port = output->ct.orig_tp.dst; 322 orig.ipv6_proto = output->ct_orig_proto; 323 324 if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6, 325 sizeof(orig), &orig)) 326 return -EMSGSIZE; 327 } 328 } 329 330 return 0; 331} 332 333static int ovs_ct_set_mark(struct nf_conn *ct, struct sw_flow_key *key, 334 u32 ct_mark, u32 mask) 335{ 336#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 337 u32 new_mark; 338 339 new_mark = ct_mark | (READ_ONCE(ct->mark) & ~(mask)); 340 if (READ_ONCE(ct->mark) != new_mark) { 341 WRITE_ONCE(ct->mark, new_mark); 342 if (nf_ct_is_confirmed(ct)) 343 nf_conntrack_event_cache(IPCT_MARK, ct); 344 key->ct.mark = new_mark; 345 } 346 347 return 0; 348#else 349 return -ENOTSUPP; 350#endif 351} 352 353static struct nf_conn_labels *ovs_ct_get_conn_labels(struct nf_conn *ct) 354{ 355 struct nf_conn_labels *cl; 356 357 cl = nf_ct_labels_find(ct); 358 if (!cl) { 359 nf_ct_labels_ext_add(ct); 360 cl = nf_ct_labels_find(ct); 361 } 362 363 return cl; 364} 365 366/* Initialize labels for a new, yet to be committed conntrack entry. Note that 367 * since the new connection is not yet confirmed, and thus no-one else has 368 * access to it's labels, we simply write them over. 369 */ 370static int ovs_ct_init_labels(struct nf_conn *ct, struct sw_flow_key *key, 371 const struct ovs_key_ct_labels *labels, 372 const struct ovs_key_ct_labels *mask) 373{ 374 struct nf_conn_labels *cl, *master_cl; 375 bool have_mask = labels_nonzero(mask); 376 377 /* Inherit master's labels to the related connection? */ 378 master_cl = ct->master ? nf_ct_labels_find(ct->master) : NULL; 379 380 if (!master_cl && !have_mask) 381 return 0; /* Nothing to do. */ 382 383 cl = ovs_ct_get_conn_labels(ct); 384 if (!cl) 385 return -ENOSPC; 386 387 /* Inherit the master's labels, if any. */ 388 if (master_cl) 389 *cl = *master_cl; 390 391 if (have_mask) { 392 u32 *dst = (u32 *)cl->bits; 393 int i; 394 395 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) 396 dst[i] = (dst[i] & ~mask->ct_labels_32[i]) | 397 (labels->ct_labels_32[i] 398 & mask->ct_labels_32[i]); 399 } 400 401 /* Labels are included in the IPCTNL_MSG_CT_NEW event only if the 402 * IPCT_LABEL bit is set in the event cache. 403 */ 404 nf_conntrack_event_cache(IPCT_LABEL, ct); 405 406 memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN); 407 408 return 0; 409} 410 411static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key, 412 const struct ovs_key_ct_labels *labels, 413 const struct ovs_key_ct_labels *mask) 414{ 415 struct nf_conn_labels *cl; 416 int err; 417 418 cl = ovs_ct_get_conn_labels(ct); 419 if (!cl) 420 return -ENOSPC; 421 422 err = nf_connlabels_replace(ct, labels->ct_labels_32, 423 mask->ct_labels_32, 424 OVS_CT_LABELS_LEN_32); 425 if (err) 426 return err; 427 428 memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN); 429 430 return 0; 431} 432 433/* 'skb' should already be pulled to nh_ofs. */ 434static int ovs_ct_helper(struct sk_buff *skb, u16 proto) 435{ 436 const struct nf_conntrack_helper *helper; 437 const struct nf_conn_help *help; 438 enum ip_conntrack_info ctinfo; 439 unsigned int protoff; 440 struct nf_conn *ct; 441 int err; 442 443 ct = nf_ct_get(skb, &ctinfo); 444 if (!ct || ctinfo == IP_CT_RELATED_REPLY) 445 return NF_ACCEPT; 446 447 help = nfct_help(ct); 448 if (!help) 449 return NF_ACCEPT; 450 451 helper = rcu_dereference(help->helper); 452 if (!helper) 453 return NF_ACCEPT; 454 455 switch (proto) { 456 case NFPROTO_IPV4: 457 protoff = ip_hdrlen(skb); 458 break; 459 case NFPROTO_IPV6: { 460 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 461 __be16 frag_off; 462 int ofs; 463 464 ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, 465 &frag_off); 466 if (ofs < 0 || (frag_off & htons(~0x7)) != 0) { 467 pr_debug("proto header not found\n"); 468 return NF_ACCEPT; 469 } 470 protoff = ofs; 471 break; 472 } 473 default: 474 WARN_ONCE(1, "helper invoked on non-IP family!"); 475 return NF_DROP; 476 } 477 478 err = helper->help(skb, protoff, ct, ctinfo); 479 if (err != NF_ACCEPT) 480 return err; 481 482 /* Adjust seqs after helper. This is needed due to some helpers (e.g., 483 * FTP with NAT) adusting the TCP payload size when mangling IP 484 * addresses and/or port numbers in the text-based control connection. 485 */ 486 if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && 487 !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) 488 return NF_DROP; 489 return NF_ACCEPT; 490} 491 492/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero 493 * value if 'skb' is freed. 494 */ 495static int handle_fragments(struct net *net, struct sw_flow_key *key, 496 u16 zone, struct sk_buff *skb) 497{ 498 struct ovs_skb_cb ovs_cb = *OVS_CB(skb); 499 int err; 500 501 if (key->eth.type == htons(ETH_P_IP)) { 502 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; 503 504 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 505 err = ip_defrag(net, skb, user); 506 if (err) 507 return err; 508 509 ovs_cb.mru = IPCB(skb)->frag_max_size; 510#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 511 } else if (key->eth.type == htons(ETH_P_IPV6)) { 512 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; 513 514 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); 515 err = nf_ct_frag6_gather(net, skb, user); 516 if (err) { 517 if (err != -EINPROGRESS) 518 kfree_skb(skb); 519 return err; 520 } 521 522 key->ip.proto = ipv6_hdr(skb)->nexthdr; 523 ovs_cb.mru = IP6CB(skb)->frag_max_size; 524#endif 525 } else { 526 kfree_skb(skb); 527 return -EPFNOSUPPORT; 528 } 529 530 /* The key extracted from the fragment that completed this datagram 531 * likely didn't have an L4 header, so regenerate it. 532 */ 533 ovs_flow_key_update_l3l4(skb, key); 534 535 key->ip.frag = OVS_FRAG_TYPE_NONE; 536 skb_clear_hash(skb); 537 skb->ignore_df = 1; 538 *OVS_CB(skb) = ovs_cb; 539 540 return 0; 541} 542 543static struct nf_conntrack_expect * 544ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone, 545 u16 proto, const struct sk_buff *skb) 546{ 547 struct nf_conntrack_tuple tuple; 548 struct nf_conntrack_expect *exp; 549 550 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple)) 551 return NULL; 552 553 exp = __nf_ct_expect_find(net, zone, &tuple); 554 if (exp) { 555 struct nf_conntrack_tuple_hash *h; 556 557 /* Delete existing conntrack entry, if it clashes with the 558 * expectation. This can happen since conntrack ALGs do not 559 * check for clashes between (new) expectations and existing 560 * conntrack entries. nf_conntrack_in() will check the 561 * expectations only if a conntrack entry can not be found, 562 * which can lead to OVS finding the expectation (here) in the 563 * init direction, but which will not be removed by the 564 * nf_conntrack_in() call, if a matching conntrack entry is 565 * found instead. In this case all init direction packets 566 * would be reported as new related packets, while reply 567 * direction packets would be reported as un-related 568 * established packets. 569 */ 570 h = nf_conntrack_find_get(net, zone, &tuple); 571 if (h) { 572 struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); 573 574 nf_ct_delete(ct, 0, 0); 575 nf_conntrack_put(&ct->ct_general); 576 } 577 } 578 579 return exp; 580} 581 582/* This replicates logic from nf_conntrack_core.c that is not exported. */ 583static enum ip_conntrack_info 584ovs_ct_get_info(const struct nf_conntrack_tuple_hash *h) 585{ 586 const struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); 587 588 if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) 589 return IP_CT_ESTABLISHED_REPLY; 590 /* Once we've had two way comms, always ESTABLISHED. */ 591 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) 592 return IP_CT_ESTABLISHED; 593 if (test_bit(IPS_EXPECTED_BIT, &ct->status)) 594 return IP_CT_RELATED; 595 return IP_CT_NEW; 596} 597 598/* Find an existing connection which this packet belongs to without 599 * re-attributing statistics or modifying the connection state. This allows an 600 * skb->_nfct lost due to an upcall to be recovered during actions execution. 601 * 602 * Must be called with rcu_read_lock. 603 * 604 * On success, populates skb->_nfct and returns the connection. Returns NULL 605 * if there is no existing entry. 606 */ 607static struct nf_conn * 608ovs_ct_find_existing(struct net *net, const struct nf_conntrack_zone *zone, 609 u8 l3num, struct sk_buff *skb, bool natted) 610{ 611 struct nf_conntrack_tuple tuple; 612 struct nf_conntrack_tuple_hash *h; 613 struct nf_conn *ct; 614 615 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), l3num, 616 net, &tuple)) { 617 pr_debug("ovs_ct_find_existing: Can't get tuple\n"); 618 return NULL; 619 } 620 621 /* Must invert the tuple if skb has been transformed by NAT. */ 622 if (natted) { 623 struct nf_conntrack_tuple inverse; 624 625 if (!nf_ct_invert_tuple(&inverse, &tuple)) { 626 pr_debug("ovs_ct_find_existing: Inversion failed!\n"); 627 return NULL; 628 } 629 tuple = inverse; 630 } 631 632 /* look for tuple match */ 633 h = nf_conntrack_find_get(net, zone, &tuple); 634 if (!h) 635 return NULL; /* Not found. */ 636 637 ct = nf_ct_tuplehash_to_ctrack(h); 638 639 /* Inverted packet tuple matches the reverse direction conntrack tuple, 640 * select the other tuplehash to get the right 'ctinfo' bits for this 641 * packet. 642 */ 643 if (natted) 644 h = &ct->tuplehash[!h->tuple.dst.dir]; 645 646 nf_ct_set(skb, ct, ovs_ct_get_info(h)); 647 return ct; 648} 649 650static 651struct nf_conn *ovs_ct_executed(struct net *net, 652 const struct sw_flow_key *key, 653 const struct ovs_conntrack_info *info, 654 struct sk_buff *skb, 655 bool *ct_executed) 656{ 657 struct nf_conn *ct = NULL; 658 659 /* If no ct, check if we have evidence that an existing conntrack entry 660 * might be found for this skb. This happens when we lose a skb->_nfct 661 * due to an upcall, or if the direction is being forced. If the 662 * connection was not confirmed, it is not cached and needs to be run 663 * through conntrack again. 664 */ 665 *ct_executed = (key->ct_state & OVS_CS_F_TRACKED) && 666 !(key->ct_state & OVS_CS_F_INVALID) && 667 (key->ct_zone == info->zone.id); 668 669 if (*ct_executed || (!key->ct_state && info->force)) { 670 ct = ovs_ct_find_existing(net, &info->zone, info->family, skb, 671 !!(key->ct_state & 672 OVS_CS_F_NAT_MASK)); 673 } 674 675 return ct; 676} 677 678/* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ 679static bool skb_nfct_cached(struct net *net, 680 const struct sw_flow_key *key, 681 const struct ovs_conntrack_info *info, 682 struct sk_buff *skb) 683{ 684 enum ip_conntrack_info ctinfo; 685 struct nf_conn *ct; 686 bool ct_executed = true; 687 688 ct = nf_ct_get(skb, &ctinfo); 689 if (!ct) 690 ct = ovs_ct_executed(net, key, info, skb, &ct_executed); 691 692 if (ct) 693 nf_ct_get(skb, &ctinfo); 694 else 695 return false; 696 697 if (!net_eq(net, read_pnet(&ct->ct_net))) 698 return false; 699 if (!nf_ct_zone_equal_any(info->ct, nf_ct_zone(ct))) 700 return false; 701 if (info->helper) { 702 struct nf_conn_help *help; 703 704 help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER); 705 if (help && rcu_access_pointer(help->helper) != info->helper) 706 return false; 707 } 708 if (info->nf_ct_timeout) { 709 struct nf_conn_timeout *timeout_ext; 710 711 timeout_ext = nf_ct_timeout_find(ct); 712 if (!timeout_ext || info->nf_ct_timeout != 713 rcu_dereference(timeout_ext->timeout)) 714 return false; 715 } 716 /* Force conntrack entry direction to the current packet? */ 717 if (info->force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 718 /* Delete the conntrack entry if confirmed, else just release 719 * the reference. 720 */ 721 if (nf_ct_is_confirmed(ct)) 722 nf_ct_delete(ct, 0, 0); 723 724 nf_conntrack_put(&ct->ct_general); 725 nf_ct_set(skb, NULL, 0); 726 return false; 727 } 728 729 return ct_executed; 730} 731 732#if IS_ENABLED(CONFIG_NF_NAT) 733static void ovs_nat_update_key(struct sw_flow_key *key, 734 const struct sk_buff *skb, 735 enum nf_nat_manip_type maniptype) 736{ 737 if (maniptype == NF_NAT_MANIP_SRC) { 738 __be16 src; 739 740 key->ct_state |= OVS_CS_F_SRC_NAT; 741 if (key->eth.type == htons(ETH_P_IP)) 742 key->ipv4.addr.src = ip_hdr(skb)->saddr; 743 else if (key->eth.type == htons(ETH_P_IPV6)) 744 memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr, 745 sizeof(key->ipv6.addr.src)); 746 else 747 return; 748 749 if (key->ip.proto == IPPROTO_UDP) 750 src = udp_hdr(skb)->source; 751 else if (key->ip.proto == IPPROTO_TCP) 752 src = tcp_hdr(skb)->source; 753 else if (key->ip.proto == IPPROTO_SCTP) 754 src = sctp_hdr(skb)->source; 755 else 756 return; 757 758 key->tp.src = src; 759 } else { 760 __be16 dst; 761 762 key->ct_state |= OVS_CS_F_DST_NAT; 763 if (key->eth.type == htons(ETH_P_IP)) 764 key->ipv4.addr.dst = ip_hdr(skb)->daddr; 765 else if (key->eth.type == htons(ETH_P_IPV6)) 766 memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr, 767 sizeof(key->ipv6.addr.dst)); 768 else 769 return; 770 771 if (key->ip.proto == IPPROTO_UDP) 772 dst = udp_hdr(skb)->dest; 773 else if (key->ip.proto == IPPROTO_TCP) 774 dst = tcp_hdr(skb)->dest; 775 else if (key->ip.proto == IPPROTO_SCTP) 776 dst = sctp_hdr(skb)->dest; 777 else 778 return; 779 780 key->tp.dst = dst; 781 } 782} 783 784/* Modelled after nf_nat_ipv[46]_fn(). 785 * range is only used for new, uninitialized NAT state. 786 * Returns either NF_ACCEPT or NF_DROP. 787 */ 788static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, 789 enum ip_conntrack_info ctinfo, 790 const struct nf_nat_range2 *range, 791 enum nf_nat_manip_type maniptype, struct sw_flow_key *key) 792{ 793 int hooknum, nh_off, err = NF_ACCEPT; 794 795 nh_off = skb_network_offset(skb); 796 skb_pull_rcsum(skb, nh_off); 797 798 /* See HOOK2MANIP(). */ 799 if (maniptype == NF_NAT_MANIP_SRC) 800 hooknum = NF_INET_LOCAL_IN; /* Source NAT */ 801 else 802 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ 803 804 switch (ctinfo) { 805 case IP_CT_RELATED: 806 case IP_CT_RELATED_REPLY: 807 if (IS_ENABLED(CONFIG_NF_NAT) && 808 skb->protocol == htons(ETH_P_IP) && 809 ip_hdr(skb)->protocol == IPPROTO_ICMP) { 810 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, 811 hooknum)) 812 err = NF_DROP; 813 goto push; 814 } else if (IS_ENABLED(CONFIG_IPV6) && 815 skb->protocol == htons(ETH_P_IPV6)) { 816 __be16 frag_off; 817 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 818 int hdrlen = ipv6_skip_exthdr(skb, 819 sizeof(struct ipv6hdr), 820 &nexthdr, &frag_off); 821 822 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { 823 if (!nf_nat_icmpv6_reply_translation(skb, ct, 824 ctinfo, 825 hooknum, 826 hdrlen)) 827 err = NF_DROP; 828 goto push; 829 } 830 } 831 /* Non-ICMP, fall thru to initialize if needed. */ 832 fallthrough; 833 case IP_CT_NEW: 834 /* Seen it before? This can happen for loopback, retrans, 835 * or local packets. 836 */ 837 if (!nf_nat_initialized(ct, maniptype)) { 838 /* Initialize according to the NAT action. */ 839 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) 840 /* Action is set up to establish a new 841 * mapping. 842 */ 843 ? nf_nat_setup_info(ct, range, maniptype) 844 : nf_nat_alloc_null_binding(ct, hooknum); 845 if (err != NF_ACCEPT) 846 goto push; 847 } 848 break; 849 850 case IP_CT_ESTABLISHED: 851 case IP_CT_ESTABLISHED_REPLY: 852 break; 853 854 default: 855 err = NF_DROP; 856 goto push; 857 } 858 859 err = nf_nat_packet(ct, ctinfo, hooknum, skb); 860push: 861 skb_push(skb, nh_off); 862 skb_postpush_rcsum(skb, skb->data, nh_off); 863 864 /* Update the flow key if NAT successful. */ 865 if (err == NF_ACCEPT) 866 ovs_nat_update_key(key, skb, maniptype); 867 868 return err; 869} 870 871/* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */ 872static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, 873 const struct ovs_conntrack_info *info, 874 struct sk_buff *skb, struct nf_conn *ct, 875 enum ip_conntrack_info ctinfo) 876{ 877 enum nf_nat_manip_type maniptype; 878 int err; 879 880 /* Add NAT extension if not confirmed yet. */ 881 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) 882 return NF_ACCEPT; /* Can't NAT. */ 883 884 /* Determine NAT type. 885 * Check if the NAT type can be deduced from the tracked connection. 886 * Make sure new expected connections (IP_CT_RELATED) are NATted only 887 * when committing. 888 */ 889 if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW && 890 ct->status & IPS_NAT_MASK && 891 (ctinfo != IP_CT_RELATED || info->commit)) { 892 /* NAT an established or related connection like before. */ 893 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) 894 /* This is the REPLY direction for a connection 895 * for which NAT was applied in the forward 896 * direction. Do the reverse NAT. 897 */ 898 maniptype = ct->status & IPS_SRC_NAT 899 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; 900 else 901 maniptype = ct->status & IPS_SRC_NAT 902 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; 903 } else if (info->nat & OVS_CT_SRC_NAT) { 904 maniptype = NF_NAT_MANIP_SRC; 905 } else if (info->nat & OVS_CT_DST_NAT) { 906 maniptype = NF_NAT_MANIP_DST; 907 } else { 908 return NF_ACCEPT; /* Connection is not NATed. */ 909 } 910 err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype, key); 911 912 if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) { 913 if (ct->status & IPS_SRC_NAT) { 914 if (maniptype == NF_NAT_MANIP_SRC) 915 maniptype = NF_NAT_MANIP_DST; 916 else 917 maniptype = NF_NAT_MANIP_SRC; 918 919 err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, 920 maniptype, key); 921 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) { 922 err = ovs_ct_nat_execute(skb, ct, ctinfo, NULL, 923 NF_NAT_MANIP_SRC, key); 924 } 925 } 926 927 return err; 928} 929#else /* !CONFIG_NF_NAT */ 930static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, 931 const struct ovs_conntrack_info *info, 932 struct sk_buff *skb, struct nf_conn *ct, 933 enum ip_conntrack_info ctinfo) 934{ 935 return NF_ACCEPT; 936} 937#endif 938 939/* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if 940 * not done already. Update key with new CT state after passing the packet 941 * through conntrack. 942 * Note that if the packet is deemed invalid by conntrack, skb->_nfct will be 943 * set to NULL and 0 will be returned. 944 */ 945static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key, 946 const struct ovs_conntrack_info *info, 947 struct sk_buff *skb) 948{ 949 /* If we are recirculating packets to match on conntrack fields and 950 * committing with a separate conntrack action, then we don't need to 951 * actually run the packet through conntrack twice unless it's for a 952 * different zone. 953 */ 954 bool cached = skb_nfct_cached(net, key, info, skb); 955 enum ip_conntrack_info ctinfo; 956 struct nf_conn *ct; 957 958 if (!cached) { 959 struct nf_hook_state state = { 960 .hook = NF_INET_PRE_ROUTING, 961 .pf = info->family, 962 .net = net, 963 }; 964 struct nf_conn *tmpl = info->ct; 965 int err; 966 967 /* Associate skb with specified zone. */ 968 if (tmpl) { 969 if (skb_nfct(skb)) 970 nf_conntrack_put(skb_nfct(skb)); 971 nf_conntrack_get(&tmpl->ct_general); 972 nf_ct_set(skb, tmpl, IP_CT_NEW); 973 } 974 975 err = nf_conntrack_in(skb, &state); 976 if (err != NF_ACCEPT) 977 return -ENOENT; 978 979 /* Clear CT state NAT flags to mark that we have not yet done 980 * NAT after the nf_conntrack_in() call. We can actually clear 981 * the whole state, as it will be re-initialized below. 982 */ 983 key->ct_state = 0; 984 985 /* Update the key, but keep the NAT flags. */ 986 ovs_ct_update_key(skb, info, key, true, true); 987 } 988 989 ct = nf_ct_get(skb, &ctinfo); 990 if (ct) { 991 bool add_helper = false; 992 993 /* Packets starting a new connection must be NATted before the 994 * helper, so that the helper knows about the NAT. We enforce 995 * this by delaying both NAT and helper calls for unconfirmed 996 * connections until the committing CT action. For later 997 * packets NAT and Helper may be called in either order. 998 * 999 * NAT will be done only if the CT action has NAT, and only 1000 * once per packet (per zone), as guarded by the NAT bits in 1001 * the key->ct_state. 1002 */ 1003 if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) && 1004 (nf_ct_is_confirmed(ct) || info->commit) && 1005 ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) { 1006 return -EINVAL; 1007 } 1008 1009 /* Userspace may decide to perform a ct lookup without a helper 1010 * specified followed by a (recirculate and) commit with one, 1011 * or attach a helper in a later commit. Therefore, for 1012 * connections which we will commit, we may need to attach 1013 * the helper here. 1014 */ 1015 if (info->commit && info->helper && !nfct_help(ct)) { 1016 int err = __nf_ct_try_assign_helper(ct, info->ct, 1017 GFP_ATOMIC); 1018 if (err) 1019 return err; 1020 add_helper = true; 1021 1022 /* helper installed, add seqadj if NAT is required */ 1023 if (info->nat && !nfct_seqadj(ct)) { 1024 if (!nfct_seqadj_ext_add(ct)) 1025 return -EINVAL; 1026 } 1027 } 1028 1029 /* Call the helper only if: 1030 * - nf_conntrack_in() was executed above ("!cached") or a 1031 * helper was just attached ("add_helper") for a confirmed 1032 * connection, or 1033 * - When committing an unconfirmed connection. 1034 */ 1035 if ((nf_ct_is_confirmed(ct) ? !cached || add_helper : 1036 info->commit) && 1037 ovs_ct_helper(skb, info->family) != NF_ACCEPT) { 1038 return -EINVAL; 1039 } 1040 } 1041 1042 return 0; 1043} 1044 1045/* Lookup connection and read fields into key. */ 1046static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key, 1047 const struct ovs_conntrack_info *info, 1048 struct sk_buff *skb) 1049{ 1050 struct nf_conntrack_expect *exp; 1051 1052 /* If we pass an expected packet through nf_conntrack_in() the 1053 * expectation is typically removed, but the packet could still be 1054 * lost in upcall processing. To prevent this from happening we 1055 * perform an explicit expectation lookup. Expected connections are 1056 * always new, and will be passed through conntrack only when they are 1057 * committed, as it is OK to remove the expectation at that time. 1058 */ 1059 exp = ovs_ct_expect_find(net, &info->zone, info->family, skb); 1060 if (exp) { 1061 u8 state; 1062 1063 /* NOTE: New connections are NATted and Helped only when 1064 * committed, so we are not calling into NAT here. 1065 */ 1066 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED; 1067 __ovs_ct_update_key(key, state, &info->zone, exp->master); 1068 } else { 1069 struct nf_conn *ct; 1070 int err; 1071 1072 err = __ovs_ct_lookup(net, key, info, skb); 1073 if (err) 1074 return err; 1075 1076 ct = (struct nf_conn *)skb_nfct(skb); 1077 if (ct) 1078 nf_ct_deliver_cached_events(ct); 1079 } 1080 1081 return 0; 1082} 1083 1084static bool labels_nonzero(const struct ovs_key_ct_labels *labels) 1085{ 1086 size_t i; 1087 1088 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) 1089 if (labels->ct_labels_32[i]) 1090 return true; 1091 1092 return false; 1093} 1094 1095#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1096static struct hlist_head *ct_limit_hash_bucket( 1097 const struct ovs_ct_limit_info *info, u16 zone) 1098{ 1099 return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)]; 1100} 1101 1102/* Call with ovs_mutex */ 1103static void ct_limit_set(const struct ovs_ct_limit_info *info, 1104 struct ovs_ct_limit *new_ct_limit) 1105{ 1106 struct ovs_ct_limit *ct_limit; 1107 struct hlist_head *head; 1108 1109 head = ct_limit_hash_bucket(info, new_ct_limit->zone); 1110 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1111 if (ct_limit->zone == new_ct_limit->zone) { 1112 hlist_replace_rcu(&ct_limit->hlist_node, 1113 &new_ct_limit->hlist_node); 1114 kfree_rcu(ct_limit, rcu); 1115 return; 1116 } 1117 } 1118 1119 hlist_add_head_rcu(&new_ct_limit->hlist_node, head); 1120} 1121 1122/* Call with ovs_mutex */ 1123static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone) 1124{ 1125 struct ovs_ct_limit *ct_limit; 1126 struct hlist_head *head; 1127 struct hlist_node *n; 1128 1129 head = ct_limit_hash_bucket(info, zone); 1130 hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) { 1131 if (ct_limit->zone == zone) { 1132 hlist_del_rcu(&ct_limit->hlist_node); 1133 kfree_rcu(ct_limit, rcu); 1134 return; 1135 } 1136 } 1137} 1138 1139/* Call with RCU read lock */ 1140static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone) 1141{ 1142 struct ovs_ct_limit *ct_limit; 1143 struct hlist_head *head; 1144 1145 head = ct_limit_hash_bucket(info, zone); 1146 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1147 if (ct_limit->zone == zone) 1148 return ct_limit->limit; 1149 } 1150 1151 return info->default_limit; 1152} 1153 1154static int ovs_ct_check_limit(struct net *net, 1155 const struct ovs_conntrack_info *info, 1156 const struct nf_conntrack_tuple *tuple) 1157{ 1158 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1159 const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 1160 u32 per_zone_limit, connections; 1161 u32 conncount_key; 1162 1163 conncount_key = info->zone.id; 1164 1165 per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id); 1166 if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED) 1167 return 0; 1168 1169 connections = nf_conncount_count(net, ct_limit_info->data, 1170 &conncount_key, tuple, &info->zone); 1171 if (connections > per_zone_limit) 1172 return -ENOMEM; 1173 1174 return 0; 1175} 1176#endif 1177 1178/* Lookup connection and confirm if unconfirmed. */ 1179static int ovs_ct_commit(struct net *net, struct sw_flow_key *key, 1180 const struct ovs_conntrack_info *info, 1181 struct sk_buff *skb) 1182{ 1183 enum ip_conntrack_info ctinfo; 1184 struct nf_conn *ct; 1185 int err; 1186 1187 err = __ovs_ct_lookup(net, key, info, skb); 1188 if (err) 1189 return err; 1190 1191 /* The connection could be invalid, in which case this is a no-op.*/ 1192 ct = nf_ct_get(skb, &ctinfo); 1193 if (!ct) 1194 return 0; 1195 1196#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1197 if (static_branch_unlikely(&ovs_ct_limit_enabled)) { 1198 if (!nf_ct_is_confirmed(ct)) { 1199 err = ovs_ct_check_limit(net, info, 1200 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); 1201 if (err) { 1202 net_warn_ratelimited("openvswitch: zone: %u " 1203 "exceeds conntrack limit\n", 1204 info->zone.id); 1205 return err; 1206 } 1207 } 1208 } 1209#endif 1210 1211 /* Set the conntrack event mask if given. NEW and DELETE events have 1212 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener 1213 * typically would receive many kinds of updates. Setting the event 1214 * mask allows those events to be filtered. The set event mask will 1215 * remain in effect for the lifetime of the connection unless changed 1216 * by a further CT action with both the commit flag and the eventmask 1217 * option. */ 1218 if (info->have_eventmask) { 1219 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct); 1220 1221 if (cache) 1222 cache->ctmask = info->eventmask; 1223 } 1224 1225 /* Apply changes before confirming the connection so that the initial 1226 * conntrack NEW netlink event carries the values given in the CT 1227 * action. 1228 */ 1229 if (info->mark.mask) { 1230 err = ovs_ct_set_mark(ct, key, info->mark.value, 1231 info->mark.mask); 1232 if (err) 1233 return err; 1234 } 1235 if (!nf_ct_is_confirmed(ct)) { 1236 err = ovs_ct_init_labels(ct, key, &info->labels.value, 1237 &info->labels.mask); 1238 if (err) 1239 return err; 1240 } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1241 labels_nonzero(&info->labels.mask)) { 1242 err = ovs_ct_set_labels(ct, key, &info->labels.value, 1243 &info->labels.mask); 1244 if (err) 1245 return err; 1246 } 1247 /* This will take care of sending queued events even if the connection 1248 * is already confirmed. 1249 */ 1250 if (nf_conntrack_confirm(skb) != NF_ACCEPT) 1251 return -EINVAL; 1252 1253 return 0; 1254} 1255 1256/* Trim the skb to the length specified by the IP/IPv6 header, 1257 * removing any trailing lower-layer padding. This prepares the skb 1258 * for higher-layer processing that assumes skb->len excludes padding 1259 * (such as nf_ip_checksum). The caller needs to pull the skb to the 1260 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 1261 */ 1262static int ovs_skb_network_trim(struct sk_buff *skb) 1263{ 1264 unsigned int len; 1265 int err; 1266 1267 switch (skb->protocol) { 1268 case htons(ETH_P_IP): 1269 len = ntohs(ip_hdr(skb)->tot_len); 1270 break; 1271 case htons(ETH_P_IPV6): 1272 len = sizeof(struct ipv6hdr) 1273 + ntohs(ipv6_hdr(skb)->payload_len); 1274 break; 1275 default: 1276 len = skb->len; 1277 } 1278 1279 err = pskb_trim_rcsum(skb, len); 1280 if (err) 1281 kfree_skb(skb); 1282 1283 return err; 1284} 1285 1286/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero 1287 * value if 'skb' is freed. 1288 */ 1289int ovs_ct_execute(struct net *net, struct sk_buff *skb, 1290 struct sw_flow_key *key, 1291 const struct ovs_conntrack_info *info) 1292{ 1293 int nh_ofs; 1294 int err; 1295 1296 /* The conntrack module expects to be working at L3. */ 1297 nh_ofs = skb_network_offset(skb); 1298 skb_pull_rcsum(skb, nh_ofs); 1299 1300 err = ovs_skb_network_trim(skb); 1301 if (err) 1302 return err; 1303 1304 if (key->ip.frag != OVS_FRAG_TYPE_NONE) { 1305 err = handle_fragments(net, key, info->zone.id, skb); 1306 if (err) 1307 return err; 1308 } 1309 1310 if (info->commit) 1311 err = ovs_ct_commit(net, key, info, skb); 1312 else 1313 err = ovs_ct_lookup(net, key, info, skb); 1314 1315 skb_push(skb, nh_ofs); 1316 skb_postpush_rcsum(skb, skb->data, nh_ofs); 1317 if (err) 1318 kfree_skb(skb); 1319 return err; 1320} 1321 1322int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key) 1323{ 1324 if (skb_nfct(skb)) { 1325 nf_conntrack_put(skb_nfct(skb)); 1326 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 1327 if (key) 1328 ovs_ct_fill_key(skb, key); 1329 } 1330 1331 return 0; 1332} 1333 1334static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name, 1335 const struct sw_flow_key *key, bool log) 1336{ 1337 struct nf_conntrack_helper *helper; 1338 struct nf_conn_help *help; 1339 int ret = 0; 1340 1341 helper = nf_conntrack_helper_try_module_get(name, info->family, 1342 key->ip.proto); 1343 if (!helper) { 1344 OVS_NLERR(log, "Unknown helper \"%s\"", name); 1345 return -EINVAL; 1346 } 1347 1348 help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL); 1349 if (!help) { 1350 nf_conntrack_helper_put(helper); 1351 return -ENOMEM; 1352 } 1353 1354#if IS_ENABLED(CONFIG_NF_NAT) 1355 if (info->nat) { 1356 ret = nf_nat_helper_try_module_get(name, info->family, 1357 key->ip.proto); 1358 if (ret) { 1359 nf_conntrack_helper_put(helper); 1360 OVS_NLERR(log, "Failed to load \"%s\" NAT helper, error: %d", 1361 name, ret); 1362 return ret; 1363 } 1364 } 1365#endif 1366 rcu_assign_pointer(help->helper, helper); 1367 info->helper = helper; 1368 return ret; 1369} 1370 1371#if IS_ENABLED(CONFIG_NF_NAT) 1372static int parse_nat(const struct nlattr *attr, 1373 struct ovs_conntrack_info *info, bool log) 1374{ 1375 struct nlattr *a; 1376 int rem; 1377 bool have_ip_max = false; 1378 bool have_proto_max = false; 1379 bool ip_vers = (info->family == NFPROTO_IPV6); 1380 1381 nla_for_each_nested(a, attr, rem) { 1382 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = { 1383 [OVS_NAT_ATTR_SRC] = {0, 0}, 1384 [OVS_NAT_ATTR_DST] = {0, 0}, 1385 [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr), 1386 sizeof(struct in6_addr)}, 1387 [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr), 1388 sizeof(struct in6_addr)}, 1389 [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)}, 1390 [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)}, 1391 [OVS_NAT_ATTR_PERSISTENT] = {0, 0}, 1392 [OVS_NAT_ATTR_PROTO_HASH] = {0, 0}, 1393 [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0}, 1394 }; 1395 int type = nla_type(a); 1396 1397 if (type > OVS_NAT_ATTR_MAX) { 1398 OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)", 1399 type, OVS_NAT_ATTR_MAX); 1400 return -EINVAL; 1401 } 1402 1403 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) { 1404 OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)", 1405 type, nla_len(a), 1406 ovs_nat_attr_lens[type][ip_vers]); 1407 return -EINVAL; 1408 } 1409 1410 switch (type) { 1411 case OVS_NAT_ATTR_SRC: 1412 case OVS_NAT_ATTR_DST: 1413 if (info->nat) { 1414 OVS_NLERR(log, "Only one type of NAT may be specified"); 1415 return -ERANGE; 1416 } 1417 info->nat |= OVS_CT_NAT; 1418 info->nat |= ((type == OVS_NAT_ATTR_SRC) 1419 ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT); 1420 break; 1421 1422 case OVS_NAT_ATTR_IP_MIN: 1423 nla_memcpy(&info->range.min_addr, a, 1424 sizeof(info->range.min_addr)); 1425 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1426 break; 1427 1428 case OVS_NAT_ATTR_IP_MAX: 1429 have_ip_max = true; 1430 nla_memcpy(&info->range.max_addr, a, 1431 sizeof(info->range.max_addr)); 1432 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1433 break; 1434 1435 case OVS_NAT_ATTR_PROTO_MIN: 1436 info->range.min_proto.all = htons(nla_get_u16(a)); 1437 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1438 break; 1439 1440 case OVS_NAT_ATTR_PROTO_MAX: 1441 have_proto_max = true; 1442 info->range.max_proto.all = htons(nla_get_u16(a)); 1443 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1444 break; 1445 1446 case OVS_NAT_ATTR_PERSISTENT: 1447 info->range.flags |= NF_NAT_RANGE_PERSISTENT; 1448 break; 1449 1450 case OVS_NAT_ATTR_PROTO_HASH: 1451 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM; 1452 break; 1453 1454 case OVS_NAT_ATTR_PROTO_RANDOM: 1455 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY; 1456 break; 1457 1458 default: 1459 OVS_NLERR(log, "Unknown nat attribute (%d)", type); 1460 return -EINVAL; 1461 } 1462 } 1463 1464 if (rem > 0) { 1465 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem); 1466 return -EINVAL; 1467 } 1468 if (!info->nat) { 1469 /* Do not allow flags if no type is given. */ 1470 if (info->range.flags) { 1471 OVS_NLERR(log, 1472 "NAT flags may be given only when NAT range (SRC or DST) is also specified." 1473 ); 1474 return -EINVAL; 1475 } 1476 info->nat = OVS_CT_NAT; /* NAT existing connections. */ 1477 } else if (!info->commit) { 1478 OVS_NLERR(log, 1479 "NAT attributes may be specified only when CT COMMIT flag is also specified." 1480 ); 1481 return -EINVAL; 1482 } 1483 /* Allow missing IP_MAX. */ 1484 if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) { 1485 memcpy(&info->range.max_addr, &info->range.min_addr, 1486 sizeof(info->range.max_addr)); 1487 } 1488 /* Allow missing PROTO_MAX. */ 1489 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1490 !have_proto_max) { 1491 info->range.max_proto.all = info->range.min_proto.all; 1492 } 1493 return 0; 1494} 1495#endif 1496 1497static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = { 1498 [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1499 [OVS_CT_ATTR_FORCE_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1500 [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16), 1501 .maxlen = sizeof(u16) }, 1502 [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark), 1503 .maxlen = sizeof(struct md_mark) }, 1504 [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels), 1505 .maxlen = sizeof(struct md_labels) }, 1506 [OVS_CT_ATTR_HELPER] = { .minlen = 1, 1507 .maxlen = NF_CT_HELPER_NAME_LEN }, 1508#if IS_ENABLED(CONFIG_NF_NAT) 1509 /* NAT length is checked when parsing the nested attributes. */ 1510 [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX }, 1511#endif 1512 [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32), 1513 .maxlen = sizeof(u32) }, 1514 [OVS_CT_ATTR_TIMEOUT] = { .minlen = 1, 1515 .maxlen = CTNL_TIMEOUT_NAME_MAX }, 1516}; 1517 1518static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info, 1519 const char **helper, bool log) 1520{ 1521 struct nlattr *a; 1522 int rem; 1523 1524 nla_for_each_nested(a, attr, rem) { 1525 int type = nla_type(a); 1526 int maxlen; 1527 int minlen; 1528 1529 if (type > OVS_CT_ATTR_MAX) { 1530 OVS_NLERR(log, 1531 "Unknown conntrack attr (type=%d, max=%d)", 1532 type, OVS_CT_ATTR_MAX); 1533 return -EINVAL; 1534 } 1535 1536 maxlen = ovs_ct_attr_lens[type].maxlen; 1537 minlen = ovs_ct_attr_lens[type].minlen; 1538 if (nla_len(a) < minlen || nla_len(a) > maxlen) { 1539 OVS_NLERR(log, 1540 "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)", 1541 type, nla_len(a), maxlen); 1542 return -EINVAL; 1543 } 1544 1545 switch (type) { 1546 case OVS_CT_ATTR_FORCE_COMMIT: 1547 info->force = true; 1548 fallthrough; 1549 case OVS_CT_ATTR_COMMIT: 1550 info->commit = true; 1551 break; 1552#ifdef CONFIG_NF_CONNTRACK_ZONES 1553 case OVS_CT_ATTR_ZONE: 1554 info->zone.id = nla_get_u16(a); 1555 break; 1556#endif 1557#ifdef CONFIG_NF_CONNTRACK_MARK 1558 case OVS_CT_ATTR_MARK: { 1559 struct md_mark *mark = nla_data(a); 1560 1561 if (!mark->mask) { 1562 OVS_NLERR(log, "ct_mark mask cannot be 0"); 1563 return -EINVAL; 1564 } 1565 info->mark = *mark; 1566 break; 1567 } 1568#endif 1569#ifdef CONFIG_NF_CONNTRACK_LABELS 1570 case OVS_CT_ATTR_LABELS: { 1571 struct md_labels *labels = nla_data(a); 1572 1573 if (!labels_nonzero(&labels->mask)) { 1574 OVS_NLERR(log, "ct_labels mask cannot be 0"); 1575 return -EINVAL; 1576 } 1577 info->labels = *labels; 1578 break; 1579 } 1580#endif 1581 case OVS_CT_ATTR_HELPER: 1582 *helper = nla_data(a); 1583 if (!memchr(*helper, '\0', nla_len(a))) { 1584 OVS_NLERR(log, "Invalid conntrack helper"); 1585 return -EINVAL; 1586 } 1587 break; 1588#if IS_ENABLED(CONFIG_NF_NAT) 1589 case OVS_CT_ATTR_NAT: { 1590 int err = parse_nat(a, info, log); 1591 1592 if (err) 1593 return err; 1594 break; 1595 } 1596#endif 1597 case OVS_CT_ATTR_EVENTMASK: 1598 info->have_eventmask = true; 1599 info->eventmask = nla_get_u32(a); 1600 break; 1601#ifdef CONFIG_NF_CONNTRACK_TIMEOUT 1602 case OVS_CT_ATTR_TIMEOUT: 1603 memcpy(info->timeout, nla_data(a), nla_len(a)); 1604 if (!memchr(info->timeout, '\0', nla_len(a))) { 1605 OVS_NLERR(log, "Invalid conntrack timeout"); 1606 return -EINVAL; 1607 } 1608 break; 1609#endif 1610 1611 default: 1612 OVS_NLERR(log, "Unknown conntrack attr (%d)", 1613 type); 1614 return -EINVAL; 1615 } 1616 } 1617 1618#ifdef CONFIG_NF_CONNTRACK_MARK 1619 if (!info->commit && info->mark.mask) { 1620 OVS_NLERR(log, 1621 "Setting conntrack mark requires 'commit' flag."); 1622 return -EINVAL; 1623 } 1624#endif 1625#ifdef CONFIG_NF_CONNTRACK_LABELS 1626 if (!info->commit && labels_nonzero(&info->labels.mask)) { 1627 OVS_NLERR(log, 1628 "Setting conntrack labels requires 'commit' flag."); 1629 return -EINVAL; 1630 } 1631#endif 1632 if (rem > 0) { 1633 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem); 1634 return -EINVAL; 1635 } 1636 1637 return 0; 1638} 1639 1640bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr) 1641{ 1642 if (attr == OVS_KEY_ATTR_CT_STATE) 1643 return true; 1644 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1645 attr == OVS_KEY_ATTR_CT_ZONE) 1646 return true; 1647 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1648 attr == OVS_KEY_ATTR_CT_MARK) 1649 return true; 1650 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1651 attr == OVS_KEY_ATTR_CT_LABELS) { 1652 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1653 1654 return ovs_net->xt_label; 1655 } 1656 1657 return false; 1658} 1659 1660int ovs_ct_copy_action(struct net *net, const struct nlattr *attr, 1661 const struct sw_flow_key *key, 1662 struct sw_flow_actions **sfa, bool log) 1663{ 1664 struct ovs_conntrack_info ct_info; 1665 const char *helper = NULL; 1666 u16 family; 1667 int err; 1668 1669 family = key_to_nfproto(key); 1670 if (family == NFPROTO_UNSPEC) { 1671 OVS_NLERR(log, "ct family unspecified"); 1672 return -EINVAL; 1673 } 1674 1675 memset(&ct_info, 0, sizeof(ct_info)); 1676 ct_info.family = family; 1677 1678 nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID, 1679 NF_CT_DEFAULT_ZONE_DIR, 0); 1680 1681 err = parse_ct(attr, &ct_info, &helper, log); 1682 if (err) 1683 return err; 1684 1685 /* Set up template for tracking connections in specific zones. */ 1686 ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL); 1687 if (!ct_info.ct) { 1688 OVS_NLERR(log, "Failed to allocate conntrack template"); 1689 return -ENOMEM; 1690 } 1691 1692 if (ct_info.timeout[0]) { 1693 if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto, 1694 ct_info.timeout)) 1695 pr_info_ratelimited("Failed to associated timeout " 1696 "policy `%s'\n", ct_info.timeout); 1697 else 1698 ct_info.nf_ct_timeout = rcu_dereference( 1699 nf_ct_timeout_find(ct_info.ct)->timeout); 1700 1701 } 1702 1703 if (helper) { 1704 err = ovs_ct_add_helper(&ct_info, helper, key, log); 1705 if (err) 1706 goto err_free_ct; 1707 } 1708 1709 err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info, 1710 sizeof(ct_info), log); 1711 if (err) 1712 goto err_free_ct; 1713 1714 __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status); 1715 nf_conntrack_get(&ct_info.ct->ct_general); 1716 return 0; 1717err_free_ct: 1718 __ovs_ct_free_action(&ct_info); 1719 return err; 1720} 1721 1722#if IS_ENABLED(CONFIG_NF_NAT) 1723static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, 1724 struct sk_buff *skb) 1725{ 1726 struct nlattr *start; 1727 1728 start = nla_nest_start_noflag(skb, OVS_CT_ATTR_NAT); 1729 if (!start) 1730 return false; 1731 1732 if (info->nat & OVS_CT_SRC_NAT) { 1733 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC)) 1734 return false; 1735 } else if (info->nat & OVS_CT_DST_NAT) { 1736 if (nla_put_flag(skb, OVS_NAT_ATTR_DST)) 1737 return false; 1738 } else { 1739 goto out; 1740 } 1741 1742 if (info->range.flags & NF_NAT_RANGE_MAP_IPS) { 1743 if (IS_ENABLED(CONFIG_NF_NAT) && 1744 info->family == NFPROTO_IPV4) { 1745 if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN, 1746 info->range.min_addr.ip) || 1747 (info->range.max_addr.ip 1748 != info->range.min_addr.ip && 1749 (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX, 1750 info->range.max_addr.ip)))) 1751 return false; 1752 } else if (IS_ENABLED(CONFIG_IPV6) && 1753 info->family == NFPROTO_IPV6) { 1754 if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN, 1755 &info->range.min_addr.in6) || 1756 (memcmp(&info->range.max_addr.in6, 1757 &info->range.min_addr.in6, 1758 sizeof(info->range.max_addr.in6)) && 1759 (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX, 1760 &info->range.max_addr.in6)))) 1761 return false; 1762 } else { 1763 return false; 1764 } 1765 } 1766 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1767 (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN, 1768 ntohs(info->range.min_proto.all)) || 1769 (info->range.max_proto.all != info->range.min_proto.all && 1770 nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX, 1771 ntohs(info->range.max_proto.all))))) 1772 return false; 1773 1774 if (info->range.flags & NF_NAT_RANGE_PERSISTENT && 1775 nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT)) 1776 return false; 1777 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM && 1778 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH)) 1779 return false; 1780 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY && 1781 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM)) 1782 return false; 1783out: 1784 nla_nest_end(skb, start); 1785 1786 return true; 1787} 1788#endif 1789 1790int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info, 1791 struct sk_buff *skb) 1792{ 1793 struct nlattr *start; 1794 1795 start = nla_nest_start_noflag(skb, OVS_ACTION_ATTR_CT); 1796 if (!start) 1797 return -EMSGSIZE; 1798 1799 if (ct_info->commit && nla_put_flag(skb, ct_info->force 1800 ? OVS_CT_ATTR_FORCE_COMMIT 1801 : OVS_CT_ATTR_COMMIT)) 1802 return -EMSGSIZE; 1803 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1804 nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id)) 1805 return -EMSGSIZE; 1806 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask && 1807 nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark), 1808 &ct_info->mark)) 1809 return -EMSGSIZE; 1810 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1811 labels_nonzero(&ct_info->labels.mask) && 1812 nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels), 1813 &ct_info->labels)) 1814 return -EMSGSIZE; 1815 if (ct_info->helper) { 1816 if (nla_put_string(skb, OVS_CT_ATTR_HELPER, 1817 ct_info->helper->name)) 1818 return -EMSGSIZE; 1819 } 1820 if (ct_info->have_eventmask && 1821 nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask)) 1822 return -EMSGSIZE; 1823 if (ct_info->timeout[0]) { 1824 if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout)) 1825 return -EMSGSIZE; 1826 } 1827 1828#if IS_ENABLED(CONFIG_NF_NAT) 1829 if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb)) 1830 return -EMSGSIZE; 1831#endif 1832 nla_nest_end(skb, start); 1833 1834 return 0; 1835} 1836 1837void ovs_ct_free_action(const struct nlattr *a) 1838{ 1839 struct ovs_conntrack_info *ct_info = nla_data(a); 1840 1841 __ovs_ct_free_action(ct_info); 1842} 1843 1844static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info) 1845{ 1846 if (ct_info->helper) { 1847#if IS_ENABLED(CONFIG_NF_NAT) 1848 if (ct_info->nat) 1849 nf_nat_helper_put(ct_info->helper); 1850#endif 1851 nf_conntrack_helper_put(ct_info->helper); 1852 } 1853 if (ct_info->ct) { 1854 if (ct_info->timeout[0]) 1855 nf_ct_destroy_timeout(ct_info->ct); 1856 nf_ct_tmpl_free(ct_info->ct); 1857 } 1858} 1859 1860#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1861static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net) 1862{ 1863 int i, err; 1864 1865 ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info), 1866 GFP_KERNEL); 1867 if (!ovs_net->ct_limit_info) 1868 return -ENOMEM; 1869 1870 ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT; 1871 ovs_net->ct_limit_info->limits = 1872 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head), 1873 GFP_KERNEL); 1874 if (!ovs_net->ct_limit_info->limits) { 1875 kfree(ovs_net->ct_limit_info); 1876 return -ENOMEM; 1877 } 1878 1879 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++) 1880 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]); 1881 1882 ovs_net->ct_limit_info->data = 1883 nf_conncount_init(net, NFPROTO_INET, sizeof(u32)); 1884 1885 if (IS_ERR(ovs_net->ct_limit_info->data)) { 1886 err = PTR_ERR(ovs_net->ct_limit_info->data); 1887 kfree(ovs_net->ct_limit_info->limits); 1888 kfree(ovs_net->ct_limit_info); 1889 pr_err("openvswitch: failed to init nf_conncount %d\n", err); 1890 return err; 1891 } 1892 return 0; 1893} 1894 1895static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net) 1896{ 1897 const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info; 1898 int i; 1899 1900 nf_conncount_destroy(net, NFPROTO_INET, info->data); 1901 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 1902 struct hlist_head *head = &info->limits[i]; 1903 struct ovs_ct_limit *ct_limit; 1904 1905 hlist_for_each_entry_rcu(ct_limit, head, hlist_node, 1906 lockdep_ovsl_is_held()) 1907 kfree_rcu(ct_limit, rcu); 1908 } 1909 kfree(info->limits); 1910 kfree(info); 1911} 1912 1913static struct sk_buff * 1914ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd, 1915 struct ovs_header **ovs_reply_header) 1916{ 1917 struct ovs_header *ovs_header = info->userhdr; 1918 struct sk_buff *skb; 1919 1920 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1921 if (!skb) 1922 return ERR_PTR(-ENOMEM); 1923 1924 *ovs_reply_header = genlmsg_put(skb, info->snd_portid, 1925 info->snd_seq, 1926 &dp_ct_limit_genl_family, 0, cmd); 1927 1928 if (!*ovs_reply_header) { 1929 nlmsg_free(skb); 1930 return ERR_PTR(-EMSGSIZE); 1931 } 1932 (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex; 1933 1934 return skb; 1935} 1936 1937static bool check_zone_id(int zone_id, u16 *pzone) 1938{ 1939 if (zone_id >= 0 && zone_id <= 65535) { 1940 *pzone = (u16)zone_id; 1941 return true; 1942 } 1943 return false; 1944} 1945 1946static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit, 1947 struct ovs_ct_limit_info *info) 1948{ 1949 struct ovs_zone_limit *zone_limit; 1950 int rem; 1951 u16 zone; 1952 1953 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1954 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1955 1956 while (rem >= sizeof(*zone_limit)) { 1957 if (unlikely(zone_limit->zone_id == 1958 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1959 ovs_lock(); 1960 info->default_limit = zone_limit->limit; 1961 ovs_unlock(); 1962 } else if (unlikely(!check_zone_id( 1963 zone_limit->zone_id, &zone))) { 1964 OVS_NLERR(true, "zone id is out of range"); 1965 } else { 1966 struct ovs_ct_limit *ct_limit; 1967 1968 ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL); 1969 if (!ct_limit) 1970 return -ENOMEM; 1971 1972 ct_limit->zone = zone; 1973 ct_limit->limit = zone_limit->limit; 1974 1975 ovs_lock(); 1976 ct_limit_set(info, ct_limit); 1977 ovs_unlock(); 1978 } 1979 rem -= NLA_ALIGN(sizeof(*zone_limit)); 1980 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 1981 NLA_ALIGN(sizeof(*zone_limit))); 1982 } 1983 1984 if (rem) 1985 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem); 1986 1987 return 0; 1988} 1989 1990static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit, 1991 struct ovs_ct_limit_info *info) 1992{ 1993 struct ovs_zone_limit *zone_limit; 1994 int rem; 1995 u16 zone; 1996 1997 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1998 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1999 2000 while (rem >= sizeof(*zone_limit)) { 2001 if (unlikely(zone_limit->zone_id == 2002 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 2003 ovs_lock(); 2004 info->default_limit = OVS_CT_LIMIT_DEFAULT; 2005 ovs_unlock(); 2006 } else if (unlikely(!check_zone_id( 2007 zone_limit->zone_id, &zone))) { 2008 OVS_NLERR(true, "zone id is out of range"); 2009 } else { 2010 ovs_lock(); 2011 ct_limit_del(info, zone); 2012 ovs_unlock(); 2013 } 2014 rem -= NLA_ALIGN(sizeof(*zone_limit)); 2015 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 2016 NLA_ALIGN(sizeof(*zone_limit))); 2017 } 2018 2019 if (rem) 2020 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem); 2021 2022 return 0; 2023} 2024 2025static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info, 2026 struct sk_buff *reply) 2027{ 2028 struct ovs_zone_limit zone_limit = { 2029 .zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE, 2030 .limit = info->default_limit, 2031 }; 2032 2033 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 2034} 2035 2036static int __ovs_ct_limit_get_zone_limit(struct net *net, 2037 struct nf_conncount_data *data, 2038 u16 zone_id, u32 limit, 2039 struct sk_buff *reply) 2040{ 2041 struct nf_conntrack_zone ct_zone; 2042 struct ovs_zone_limit zone_limit; 2043 u32 conncount_key = zone_id; 2044 2045 zone_limit.zone_id = zone_id; 2046 zone_limit.limit = limit; 2047 nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0); 2048 2049 zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL, 2050 &ct_zone); 2051 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 2052} 2053 2054static int ovs_ct_limit_get_zone_limit(struct net *net, 2055 struct nlattr *nla_zone_limit, 2056 struct ovs_ct_limit_info *info, 2057 struct sk_buff *reply) 2058{ 2059 struct ovs_zone_limit *zone_limit; 2060 int rem, err; 2061 u32 limit; 2062 u16 zone; 2063 2064 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 2065 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 2066 2067 while (rem >= sizeof(*zone_limit)) { 2068 if (unlikely(zone_limit->zone_id == 2069 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 2070 err = ovs_ct_limit_get_default_limit(info, reply); 2071 if (err) 2072 return err; 2073 } else if (unlikely(!check_zone_id(zone_limit->zone_id, 2074 &zone))) { 2075 OVS_NLERR(true, "zone id is out of range"); 2076 } else { 2077 rcu_read_lock(); 2078 limit = ct_limit_get(info, zone); 2079 rcu_read_unlock(); 2080 2081 err = __ovs_ct_limit_get_zone_limit( 2082 net, info->data, zone, limit, reply); 2083 if (err) 2084 return err; 2085 } 2086 rem -= NLA_ALIGN(sizeof(*zone_limit)); 2087 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 2088 NLA_ALIGN(sizeof(*zone_limit))); 2089 } 2090 2091 if (rem) 2092 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem); 2093 2094 return 0; 2095} 2096 2097static int ovs_ct_limit_get_all_zone_limit(struct net *net, 2098 struct ovs_ct_limit_info *info, 2099 struct sk_buff *reply) 2100{ 2101 struct ovs_ct_limit *ct_limit; 2102 struct hlist_head *head; 2103 int i, err = 0; 2104 2105 err = ovs_ct_limit_get_default_limit(info, reply); 2106 if (err) 2107 return err; 2108 2109 rcu_read_lock(); 2110 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 2111 head = &info->limits[i]; 2112 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 2113 err = __ovs_ct_limit_get_zone_limit(net, info->data, 2114 ct_limit->zone, ct_limit->limit, reply); 2115 if (err) 2116 goto exit_err; 2117 } 2118 } 2119 2120exit_err: 2121 rcu_read_unlock(); 2122 return err; 2123} 2124 2125static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info) 2126{ 2127 struct nlattr **a = info->attrs; 2128 struct sk_buff *reply; 2129 struct ovs_header *ovs_reply_header; 2130 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2131 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2132 int err; 2133 2134 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET, 2135 &ovs_reply_header); 2136 if (IS_ERR(reply)) 2137 return PTR_ERR(reply); 2138 2139 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2140 err = -EINVAL; 2141 goto exit_err; 2142 } 2143 2144 err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2145 ct_limit_info); 2146 if (err) 2147 goto exit_err; 2148 2149 static_branch_enable(&ovs_ct_limit_enabled); 2150 2151 genlmsg_end(reply, ovs_reply_header); 2152 return genlmsg_reply(reply, info); 2153 2154exit_err: 2155 nlmsg_free(reply); 2156 return err; 2157} 2158 2159static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info) 2160{ 2161 struct nlattr **a = info->attrs; 2162 struct sk_buff *reply; 2163 struct ovs_header *ovs_reply_header; 2164 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2165 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2166 int err; 2167 2168 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL, 2169 &ovs_reply_header); 2170 if (IS_ERR(reply)) 2171 return PTR_ERR(reply); 2172 2173 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2174 err = -EINVAL; 2175 goto exit_err; 2176 } 2177 2178 err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2179 ct_limit_info); 2180 if (err) 2181 goto exit_err; 2182 2183 genlmsg_end(reply, ovs_reply_header); 2184 return genlmsg_reply(reply, info); 2185 2186exit_err: 2187 nlmsg_free(reply); 2188 return err; 2189} 2190 2191static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info) 2192{ 2193 struct nlattr **a = info->attrs; 2194 struct nlattr *nla_reply; 2195 struct sk_buff *reply; 2196 struct ovs_header *ovs_reply_header; 2197 struct net *net = sock_net(skb->sk); 2198 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2199 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2200 int err; 2201 2202 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET, 2203 &ovs_reply_header); 2204 if (IS_ERR(reply)) 2205 return PTR_ERR(reply); 2206 2207 nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT); 2208 if (!nla_reply) { 2209 err = -EMSGSIZE; 2210 goto exit_err; 2211 } 2212 2213 if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2214 err = ovs_ct_limit_get_zone_limit( 2215 net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info, 2216 reply); 2217 if (err) 2218 goto exit_err; 2219 } else { 2220 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info, 2221 reply); 2222 if (err) 2223 goto exit_err; 2224 } 2225 2226 nla_nest_end(reply, nla_reply); 2227 genlmsg_end(reply, ovs_reply_header); 2228 return genlmsg_reply(reply, info); 2229 2230exit_err: 2231 nlmsg_free(reply); 2232 return err; 2233} 2234 2235static const struct genl_small_ops ct_limit_genl_ops[] = { 2236 { .cmd = OVS_CT_LIMIT_CMD_SET, 2237 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2238 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2239 * privilege. */ 2240 .doit = ovs_ct_limit_cmd_set, 2241 }, 2242 { .cmd = OVS_CT_LIMIT_CMD_DEL, 2243 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2244 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2245 * privilege. */ 2246 .doit = ovs_ct_limit_cmd_del, 2247 }, 2248 { .cmd = OVS_CT_LIMIT_CMD_GET, 2249 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2250 .flags = 0, /* OK for unprivileged users. */ 2251 .doit = ovs_ct_limit_cmd_get, 2252 }, 2253}; 2254 2255static const struct genl_multicast_group ovs_ct_limit_multicast_group = { 2256 .name = OVS_CT_LIMIT_MCGROUP, 2257}; 2258 2259struct genl_family dp_ct_limit_genl_family __ro_after_init = { 2260 .hdrsize = sizeof(struct ovs_header), 2261 .name = OVS_CT_LIMIT_FAMILY, 2262 .version = OVS_CT_LIMIT_VERSION, 2263 .maxattr = OVS_CT_LIMIT_ATTR_MAX, 2264 .policy = ct_limit_policy, 2265 .netnsok = true, 2266 .parallel_ops = true, 2267 .small_ops = ct_limit_genl_ops, 2268 .n_small_ops = ARRAY_SIZE(ct_limit_genl_ops), 2269 .mcgrps = &ovs_ct_limit_multicast_group, 2270 .n_mcgrps = 1, 2271 .module = THIS_MODULE, 2272}; 2273#endif 2274 2275int ovs_ct_init(struct net *net) 2276{ 2277 unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE; 2278 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2279 2280 if (nf_connlabels_get(net, n_bits - 1)) { 2281 ovs_net->xt_label = false; 2282 OVS_NLERR(true, "Failed to set connlabel length"); 2283 } else { 2284 ovs_net->xt_label = true; 2285 } 2286 2287#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2288 return ovs_ct_limit_init(net, ovs_net); 2289#else 2290 return 0; 2291#endif 2292} 2293 2294void ovs_ct_exit(struct net *net) 2295{ 2296 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2297 2298#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2299 ovs_ct_limit_exit(net, ovs_net); 2300#endif 2301 2302 if (ovs_net->xt_label) 2303 nf_connlabels_put(net); 2304} 2305