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 33 struct ovs_ct_len_tbl { 34 int maxlen; 35 int minlen; 36 }; 37 38 /* Metadata mark for masked write to conntrack mark */ 39 struct md_mark { 40 u32 value; 41 u32 mask; 42 }; 43 44 /* Metadata label for masked write to conntrack label. */ 45 struct md_labels { 46 struct ovs_key_ct_labels value; 47 struct ovs_key_ct_labels mask; 48 }; 49 50 enum 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. */ 57 struct 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 80 static DEFINE_STATIC_KEY_FALSE(ovs_ct_limit_enabled); 81 82 struct 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 90 struct ovs_ct_limit_info { 91 u32 default_limit; 92 struct hlist_head *limits; 93 struct nf_conncount_data *data; 94 }; 95 96 static 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 100 101 static bool labels_nonzero(const struct ovs_key_ct_labels *labels); 102 103 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info); 104 105 static 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. */ 118 static 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 } 149 150 static u32 ovs_ct_get_mark(const struct nf_conn *ct) 151 { 152 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 153 return ct ? 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 163 164 static 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 } 174 175 static 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 } 188 189 static 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 */ 233 static 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 */ 274 void ovs_ct_fill_key(const struct sk_buff *skb, 275 struct sw_flow_key *key, 276 bool post_ct) 277 { 278 ovs_ct_update_key(skb, NULL, key, post_ct, false); 279 } 280 281 int ovs_ct_put_key(const struct sw_flow_key *swkey, 282 const struct sw_flow_key *output, struct sk_buff *skb) 283 { 284 if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, output->ct_state)) 285 return -EMSGSIZE; 286 287 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 288 nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, output->ct_zone)) 289 return -EMSGSIZE; 290 291 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 292 nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, output->ct.mark)) 293 return -EMSGSIZE; 294 295 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 296 nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(output->ct.labels), 297 &output->ct.labels)) 298 return -EMSGSIZE; 299 300 if (swkey->ct_orig_proto) { 301 if (swkey->eth.type == htons(ETH_P_IP)) { 302 struct ovs_key_ct_tuple_ipv4 orig; 303 304 memset(&orig, 0, sizeof(orig)); 305 orig.ipv4_src = output->ipv4.ct_orig.src; 306 orig.ipv4_dst = output->ipv4.ct_orig.dst; 307 orig.src_port = output->ct.orig_tp.src; 308 orig.dst_port = output->ct.orig_tp.dst; 309 orig.ipv4_proto = output->ct_orig_proto; 310 311 if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4, 312 sizeof(orig), &orig)) 313 return -EMSGSIZE; 314 } else if (swkey->eth.type == htons(ETH_P_IPV6)) { 315 struct ovs_key_ct_tuple_ipv6 orig; 316 317 memset(&orig, 0, sizeof(orig)); 318 memcpy(orig.ipv6_src, output->ipv6.ct_orig.src.s6_addr32, 319 sizeof(orig.ipv6_src)); 320 memcpy(orig.ipv6_dst, output->ipv6.ct_orig.dst.s6_addr32, 321 sizeof(orig.ipv6_dst)); 322 orig.src_port = output->ct.orig_tp.src; 323 orig.dst_port = output->ct.orig_tp.dst; 324 orig.ipv6_proto = output->ct_orig_proto; 325 326 if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6, 327 sizeof(orig), &orig)) 328 return -EMSGSIZE; 329 } 330 } 331 332 return 0; 333 } 334 335 static int ovs_ct_set_mark(struct nf_conn *ct, struct sw_flow_key *key, 336 u32 ct_mark, u32 mask) 337 { 338 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 339 u32 new_mark; 340 341 new_mark = ct_mark | (ct->mark & ~(mask)); 342 if (ct->mark != new_mark) { 343 ct->mark = new_mark; 344 if (nf_ct_is_confirmed(ct)) 345 nf_conntrack_event_cache(IPCT_MARK, ct); 346 key->ct.mark = new_mark; 347 } 348 349 return 0; 350 #else 351 return -ENOTSUPP; 352 #endif 353 } 354 355 static struct nf_conn_labels *ovs_ct_get_conn_labels(struct nf_conn *ct) 356 { 357 struct nf_conn_labels *cl; 358 359 cl = nf_ct_labels_find(ct); 360 if (!cl) { 361 nf_ct_labels_ext_add(ct); 362 cl = nf_ct_labels_find(ct); 363 } 364 365 return cl; 366 } 367 368 /* Initialize labels for a new, yet to be committed conntrack entry. Note that 369 * since the new connection is not yet confirmed, and thus no-one else has 370 * access to it's labels, we simply write them over. 371 */ 372 static int ovs_ct_init_labels(struct nf_conn *ct, struct sw_flow_key *key, 373 const struct ovs_key_ct_labels *labels, 374 const struct ovs_key_ct_labels *mask) 375 { 376 struct nf_conn_labels *cl, *master_cl; 377 bool have_mask = labels_nonzero(mask); 378 379 /* Inherit master's labels to the related connection? */ 380 master_cl = ct->master ? nf_ct_labels_find(ct->master) : NULL; 381 382 if (!master_cl && !have_mask) 383 return 0; /* Nothing to do. */ 384 385 cl = ovs_ct_get_conn_labels(ct); 386 if (!cl) 387 return -ENOSPC; 388 389 /* Inherit the master's labels, if any. */ 390 if (master_cl) 391 *cl = *master_cl; 392 393 if (have_mask) { 394 u32 *dst = (u32 *)cl->bits; 395 int i; 396 397 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) 398 dst[i] = (dst[i] & ~mask->ct_labels_32[i]) | 399 (labels->ct_labels_32[i] 400 & mask->ct_labels_32[i]); 401 } 402 403 /* Labels are included in the IPCTNL_MSG_CT_NEW event only if the 404 * IPCT_LABEL bit is set in the event cache. 405 */ 406 nf_conntrack_event_cache(IPCT_LABEL, ct); 407 408 memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN); 409 410 return 0; 411 } 412 413 static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key, 414 const struct ovs_key_ct_labels *labels, 415 const struct ovs_key_ct_labels *mask) 416 { 417 struct nf_conn_labels *cl; 418 int err; 419 420 cl = ovs_ct_get_conn_labels(ct); 421 if (!cl) 422 return -ENOSPC; 423 424 err = nf_connlabels_replace(ct, labels->ct_labels_32, 425 mask->ct_labels_32, 426 OVS_CT_LABELS_LEN_32); 427 if (err) 428 return err; 429 430 memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN); 431 432 return 0; 433 } 434 435 /* 'skb' should already be pulled to nh_ofs. */ 436 static int ovs_ct_helper(struct sk_buff *skb, u16 proto) 437 { 438 const struct nf_conntrack_helper *helper; 439 const struct nf_conn_help *help; 440 enum ip_conntrack_info ctinfo; 441 unsigned int protoff; 442 struct nf_conn *ct; 443 int err; 444 445 ct = nf_ct_get(skb, &ctinfo); 446 if (!ct || ctinfo == IP_CT_RELATED_REPLY) 447 return NF_ACCEPT; 448 449 help = nfct_help(ct); 450 if (!help) 451 return NF_ACCEPT; 452 453 helper = rcu_dereference(help->helper); 454 if (!helper) 455 return NF_ACCEPT; 456 457 switch (proto) { 458 case NFPROTO_IPV4: 459 protoff = ip_hdrlen(skb); 460 break; 461 case NFPROTO_IPV6: { 462 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 463 __be16 frag_off; 464 int ofs; 465 466 ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, 467 &frag_off); 468 if (ofs < 0 || (frag_off & htons(~0x7)) != 0) { 469 pr_debug("proto header not found\n"); 470 return NF_ACCEPT; 471 } 472 protoff = ofs; 473 break; 474 } 475 default: 476 WARN_ONCE(1, "helper invoked on non-IP family!"); 477 return NF_DROP; 478 } 479 480 err = helper->help(skb, protoff, ct, ctinfo); 481 if (err != NF_ACCEPT) 482 return err; 483 484 /* Adjust seqs after helper. This is needed due to some helpers (e.g., 485 * FTP with NAT) adusting the TCP payload size when mangling IP 486 * addresses and/or port numbers in the text-based control connection. 487 */ 488 if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && 489 !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) 490 return NF_DROP; 491 return NF_ACCEPT; 492 } 493 494 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero 495 * value if 'skb' is freed. 496 */ 497 static int handle_fragments(struct net *net, struct sw_flow_key *key, 498 u16 zone, struct sk_buff *skb) 499 { 500 struct ovs_skb_cb ovs_cb = *OVS_CB(skb); 501 int err; 502 503 if (key->eth.type == htons(ETH_P_IP)) { 504 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; 505 506 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 507 err = ip_defrag(net, skb, user); 508 if (err) 509 return err; 510 511 ovs_cb.mru = IPCB(skb)->frag_max_size; 512 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 513 } else if (key->eth.type == htons(ETH_P_IPV6)) { 514 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; 515 516 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); 517 err = nf_ct_frag6_gather(net, skb, user); 518 if (err) { 519 if (err != -EINPROGRESS) 520 kfree_skb(skb); 521 return err; 522 } 523 524 key->ip.proto = ipv6_hdr(skb)->nexthdr; 525 ovs_cb.mru = IP6CB(skb)->frag_max_size; 526 #endif 527 } else { 528 kfree_skb(skb); 529 return -EPFNOSUPPORT; 530 } 531 532 /* The key extracted from the fragment that completed this datagram 533 * likely didn't have an L4 header, so regenerate it. 534 */ 535 ovs_flow_key_update_l3l4(skb, key); 536 537 key->ip.frag = OVS_FRAG_TYPE_NONE; 538 skb_clear_hash(skb); 539 skb->ignore_df = 1; 540 *OVS_CB(skb) = ovs_cb; 541 542 return 0; 543 } 544 545 static struct nf_conntrack_expect * 546 ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone, 547 u16 proto, const struct sk_buff *skb) 548 { 549 struct nf_conntrack_tuple tuple; 550 struct nf_conntrack_expect *exp; 551 552 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple)) 553 return NULL; 554 555 exp = __nf_ct_expect_find(net, zone, &tuple); 556 if (exp) { 557 struct nf_conntrack_tuple_hash *h; 558 559 /* Delete existing conntrack entry, if it clashes with the 560 * expectation. This can happen since conntrack ALGs do not 561 * check for clashes between (new) expectations and existing 562 * conntrack entries. nf_conntrack_in() will check the 563 * expectations only if a conntrack entry can not be found, 564 * which can lead to OVS finding the expectation (here) in the 565 * init direction, but which will not be removed by the 566 * nf_conntrack_in() call, if a matching conntrack entry is 567 * found instead. In this case all init direction packets 568 * would be reported as new related packets, while reply 569 * direction packets would be reported as un-related 570 * established packets. 571 */ 572 h = nf_conntrack_find_get(net, zone, &tuple); 573 if (h) { 574 struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); 575 576 nf_ct_delete(ct, 0, 0); 577 nf_conntrack_put(&ct->ct_general); 578 } 579 } 580 581 return exp; 582 } 583 584 /* This replicates logic from nf_conntrack_core.c that is not exported. */ 585 static enum ip_conntrack_info 586 ovs_ct_get_info(const struct nf_conntrack_tuple_hash *h) 587 { 588 const struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h); 589 590 if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) 591 return IP_CT_ESTABLISHED_REPLY; 592 /* Once we've had two way comms, always ESTABLISHED. */ 593 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status)) 594 return IP_CT_ESTABLISHED; 595 if (test_bit(IPS_EXPECTED_BIT, &ct->status)) 596 return IP_CT_RELATED; 597 return IP_CT_NEW; 598 } 599 600 /* Find an existing connection which this packet belongs to without 601 * re-attributing statistics or modifying the connection state. This allows an 602 * skb->_nfct lost due to an upcall to be recovered during actions execution. 603 * 604 * Must be called with rcu_read_lock. 605 * 606 * On success, populates skb->_nfct and returns the connection. Returns NULL 607 * if there is no existing entry. 608 */ 609 static struct nf_conn * 610 ovs_ct_find_existing(struct net *net, const struct nf_conntrack_zone *zone, 611 u8 l3num, struct sk_buff *skb, bool natted) 612 { 613 struct nf_conntrack_tuple tuple; 614 struct nf_conntrack_tuple_hash *h; 615 struct nf_conn *ct; 616 617 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), l3num, 618 net, &tuple)) { 619 pr_debug("ovs_ct_find_existing: Can't get tuple\n"); 620 return NULL; 621 } 622 623 /* Must invert the tuple if skb has been transformed by NAT. */ 624 if (natted) { 625 struct nf_conntrack_tuple inverse; 626 627 if (!nf_ct_invert_tuple(&inverse, &tuple)) { 628 pr_debug("ovs_ct_find_existing: Inversion failed!\n"); 629 return NULL; 630 } 631 tuple = inverse; 632 } 633 634 /* look for tuple match */ 635 h = nf_conntrack_find_get(net, zone, &tuple); 636 if (!h) 637 return NULL; /* Not found. */ 638 639 ct = nf_ct_tuplehash_to_ctrack(h); 640 641 /* Inverted packet tuple matches the reverse direction conntrack tuple, 642 * select the other tuplehash to get the right 'ctinfo' bits for this 643 * packet. 644 */ 645 if (natted) 646 h = &ct->tuplehash[!h->tuple.dst.dir]; 647 648 nf_ct_set(skb, ct, ovs_ct_get_info(h)); 649 return ct; 650 } 651 652 static 653 struct nf_conn *ovs_ct_executed(struct net *net, 654 const struct sw_flow_key *key, 655 const struct ovs_conntrack_info *info, 656 struct sk_buff *skb, 657 bool *ct_executed) 658 { 659 struct nf_conn *ct = NULL; 660 661 /* If no ct, check if we have evidence that an existing conntrack entry 662 * might be found for this skb. This happens when we lose a skb->_nfct 663 * due to an upcall, or if the direction is being forced. If the 664 * connection was not confirmed, it is not cached and needs to be run 665 * through conntrack again. 666 */ 667 *ct_executed = (key->ct_state & OVS_CS_F_TRACKED) && 668 !(key->ct_state & OVS_CS_F_INVALID) && 669 (key->ct_zone == info->zone.id); 670 671 if (*ct_executed || (!key->ct_state && info->force)) { 672 ct = ovs_ct_find_existing(net, &info->zone, info->family, skb, 673 !!(key->ct_state & 674 OVS_CS_F_NAT_MASK)); 675 } 676 677 return ct; 678 } 679 680 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */ 681 static bool skb_nfct_cached(struct net *net, 682 const struct sw_flow_key *key, 683 const struct ovs_conntrack_info *info, 684 struct sk_buff *skb) 685 { 686 enum ip_conntrack_info ctinfo; 687 struct nf_conn *ct; 688 bool ct_executed = true; 689 690 ct = nf_ct_get(skb, &ctinfo); 691 if (!ct) 692 ct = ovs_ct_executed(net, key, info, skb, &ct_executed); 693 694 if (ct) 695 nf_ct_get(skb, &ctinfo); 696 else 697 return false; 698 699 if (!net_eq(net, read_pnet(&ct->ct_net))) 700 return false; 701 if (!nf_ct_zone_equal_any(info->ct, nf_ct_zone(ct))) 702 return false; 703 if (info->helper) { 704 struct nf_conn_help *help; 705 706 help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER); 707 if (help && rcu_access_pointer(help->helper) != info->helper) 708 return false; 709 } 710 if (info->nf_ct_timeout) { 711 struct nf_conn_timeout *timeout_ext; 712 713 timeout_ext = nf_ct_timeout_find(ct); 714 if (!timeout_ext || info->nf_ct_timeout != 715 rcu_dereference(timeout_ext->timeout)) 716 return false; 717 } 718 /* Force conntrack entry direction to the current packet? */ 719 if (info->force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 720 /* Delete the conntrack entry if confirmed, else just release 721 * the reference. 722 */ 723 if (nf_ct_is_confirmed(ct)) 724 nf_ct_delete(ct, 0, 0); 725 726 nf_conntrack_put(&ct->ct_general); 727 nf_ct_set(skb, NULL, 0); 728 return false; 729 } 730 731 return ct_executed; 732 } 733 734 #if IS_ENABLED(CONFIG_NF_NAT) 735 /* Modelled after nf_nat_ipv[46]_fn(). 736 * range is only used for new, uninitialized NAT state. 737 * Returns either NF_ACCEPT or NF_DROP. 738 */ 739 static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, 740 enum ip_conntrack_info ctinfo, 741 const struct nf_nat_range2 *range, 742 enum nf_nat_manip_type maniptype) 743 { 744 int hooknum, nh_off, err = NF_ACCEPT; 745 746 nh_off = skb_network_offset(skb); 747 skb_pull_rcsum(skb, nh_off); 748 749 /* See HOOK2MANIP(). */ 750 if (maniptype == NF_NAT_MANIP_SRC) 751 hooknum = NF_INET_LOCAL_IN; /* Source NAT */ 752 else 753 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ 754 755 switch (ctinfo) { 756 case IP_CT_RELATED: 757 case IP_CT_RELATED_REPLY: 758 if (IS_ENABLED(CONFIG_NF_NAT) && 759 skb->protocol == htons(ETH_P_IP) && 760 ip_hdr(skb)->protocol == IPPROTO_ICMP) { 761 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, 762 hooknum)) 763 err = NF_DROP; 764 goto push; 765 } else if (IS_ENABLED(CONFIG_IPV6) && 766 skb->protocol == htons(ETH_P_IPV6)) { 767 __be16 frag_off; 768 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 769 int hdrlen = ipv6_skip_exthdr(skb, 770 sizeof(struct ipv6hdr), 771 &nexthdr, &frag_off); 772 773 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { 774 if (!nf_nat_icmpv6_reply_translation(skb, ct, 775 ctinfo, 776 hooknum, 777 hdrlen)) 778 err = NF_DROP; 779 goto push; 780 } 781 } 782 /* Non-ICMP, fall thru to initialize if needed. */ 783 fallthrough; 784 case IP_CT_NEW: 785 /* Seen it before? This can happen for loopback, retrans, 786 * or local packets. 787 */ 788 if (!nf_nat_initialized(ct, maniptype)) { 789 /* Initialize according to the NAT action. */ 790 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) 791 /* Action is set up to establish a new 792 * mapping. 793 */ 794 ? nf_nat_setup_info(ct, range, maniptype) 795 : nf_nat_alloc_null_binding(ct, hooknum); 796 if (err != NF_ACCEPT) 797 goto push; 798 } 799 break; 800 801 case IP_CT_ESTABLISHED: 802 case IP_CT_ESTABLISHED_REPLY: 803 break; 804 805 default: 806 err = NF_DROP; 807 goto push; 808 } 809 810 err = nf_nat_packet(ct, ctinfo, hooknum, skb); 811 push: 812 skb_push_rcsum(skb, nh_off); 813 814 return err; 815 } 816 817 static void ovs_nat_update_key(struct sw_flow_key *key, 818 const struct sk_buff *skb, 819 enum nf_nat_manip_type maniptype) 820 { 821 if (maniptype == NF_NAT_MANIP_SRC) { 822 __be16 src; 823 824 key->ct_state |= OVS_CS_F_SRC_NAT; 825 if (key->eth.type == htons(ETH_P_IP)) 826 key->ipv4.addr.src = ip_hdr(skb)->saddr; 827 else if (key->eth.type == htons(ETH_P_IPV6)) 828 memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr, 829 sizeof(key->ipv6.addr.src)); 830 else 831 return; 832 833 if (key->ip.proto == IPPROTO_UDP) 834 src = udp_hdr(skb)->source; 835 else if (key->ip.proto == IPPROTO_TCP) 836 src = tcp_hdr(skb)->source; 837 else if (key->ip.proto == IPPROTO_SCTP) 838 src = sctp_hdr(skb)->source; 839 else 840 return; 841 842 key->tp.src = src; 843 } else { 844 __be16 dst; 845 846 key->ct_state |= OVS_CS_F_DST_NAT; 847 if (key->eth.type == htons(ETH_P_IP)) 848 key->ipv4.addr.dst = ip_hdr(skb)->daddr; 849 else if (key->eth.type == htons(ETH_P_IPV6)) 850 memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr, 851 sizeof(key->ipv6.addr.dst)); 852 else 853 return; 854 855 if (key->ip.proto == IPPROTO_UDP) 856 dst = udp_hdr(skb)->dest; 857 else if (key->ip.proto == IPPROTO_TCP) 858 dst = tcp_hdr(skb)->dest; 859 else if (key->ip.proto == IPPROTO_SCTP) 860 dst = sctp_hdr(skb)->dest; 861 else 862 return; 863 864 key->tp.dst = dst; 865 } 866 } 867 868 /* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */ 869 static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, 870 const struct ovs_conntrack_info *info, 871 struct sk_buff *skb, struct nf_conn *ct, 872 enum ip_conntrack_info ctinfo) 873 { 874 enum nf_nat_manip_type maniptype; 875 int err; 876 877 /* Add NAT extension if not confirmed yet. */ 878 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) 879 return NF_ACCEPT; /* Can't NAT. */ 880 881 /* Determine NAT type. 882 * Check if the NAT type can be deduced from the tracked connection. 883 * Make sure new expected connections (IP_CT_RELATED) are NATted only 884 * when committing. 885 */ 886 if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW && 887 ct->status & IPS_NAT_MASK && 888 (ctinfo != IP_CT_RELATED || info->commit)) { 889 /* NAT an established or related connection like before. */ 890 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) 891 /* This is the REPLY direction for a connection 892 * for which NAT was applied in the forward 893 * direction. Do the reverse NAT. 894 */ 895 maniptype = ct->status & IPS_SRC_NAT 896 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; 897 else 898 maniptype = ct->status & IPS_SRC_NAT 899 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; 900 } else if (info->nat & OVS_CT_SRC_NAT) { 901 maniptype = NF_NAT_MANIP_SRC; 902 } else if (info->nat & OVS_CT_DST_NAT) { 903 maniptype = NF_NAT_MANIP_DST; 904 } else { 905 return NF_ACCEPT; /* Connection is not NATed. */ 906 } 907 err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype); 908 909 if (err == NF_ACCEPT && ct->status & IPS_DST_NAT) { 910 if (ct->status & IPS_SRC_NAT) { 911 if (maniptype == NF_NAT_MANIP_SRC) 912 maniptype = NF_NAT_MANIP_DST; 913 else 914 maniptype = NF_NAT_MANIP_SRC; 915 916 err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, 917 maniptype); 918 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) { 919 err = ovs_ct_nat_execute(skb, ct, ctinfo, NULL, 920 NF_NAT_MANIP_SRC); 921 } 922 } 923 924 /* Mark NAT done if successful and update the flow key. */ 925 if (err == NF_ACCEPT) 926 ovs_nat_update_key(key, skb, maniptype); 927 928 return err; 929 } 930 #else /* !CONFIG_NF_NAT */ 931 static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, 932 const struct ovs_conntrack_info *info, 933 struct sk_buff *skb, struct nf_conn *ct, 934 enum ip_conntrack_info ctinfo) 935 { 936 return NF_ACCEPT; 937 } 938 #endif 939 940 /* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if 941 * not done already. Update key with new CT state after passing the packet 942 * through conntrack. 943 * Note that if the packet is deemed invalid by conntrack, skb->_nfct will be 944 * set to NULL and 0 will be returned. 945 */ 946 static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key, 947 const struct ovs_conntrack_info *info, 948 struct sk_buff *skb) 949 { 950 /* If we are recirculating packets to match on conntrack fields and 951 * committing with a separate conntrack action, then we don't need to 952 * actually run the packet through conntrack twice unless it's for a 953 * different zone. 954 */ 955 bool cached = skb_nfct_cached(net, key, info, skb); 956 enum ip_conntrack_info ctinfo; 957 struct nf_conn *ct; 958 959 if (!cached) { 960 struct nf_hook_state state = { 961 .hook = NF_INET_PRE_ROUTING, 962 .pf = info->family, 963 .net = net, 964 }; 965 struct nf_conn *tmpl = info->ct; 966 int err; 967 968 /* Associate skb with specified zone. */ 969 if (tmpl) { 970 if (skb_nfct(skb)) 971 nf_conntrack_put(skb_nfct(skb)); 972 nf_conntrack_get(&tmpl->ct_general); 973 nf_ct_set(skb, tmpl, IP_CT_NEW); 974 } 975 976 err = nf_conntrack_in(skb, &state); 977 if (err != NF_ACCEPT) 978 return -ENOENT; 979 980 /* Clear CT state NAT flags to mark that we have not yet done 981 * NAT after the nf_conntrack_in() call. We can actually clear 982 * the whole state, as it will be re-initialized below. 983 */ 984 key->ct_state = 0; 985 986 /* Update the key, but keep the NAT flags. */ 987 ovs_ct_update_key(skb, info, key, true, true); 988 } 989 990 ct = nf_ct_get(skb, &ctinfo); 991 if (ct) { 992 bool add_helper = false; 993 994 /* Packets starting a new connection must be NATted before the 995 * helper, so that the helper knows about the NAT. We enforce 996 * this by delaying both NAT and helper calls for unconfirmed 997 * connections until the committing CT action. For later 998 * packets NAT and Helper may be called in either order. 999 * 1000 * NAT will be done only if the CT action has NAT, and only 1001 * once per packet (per zone), as guarded by the NAT bits in 1002 * the key->ct_state. 1003 */ 1004 if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) && 1005 (nf_ct_is_confirmed(ct) || info->commit) && 1006 ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) { 1007 return -EINVAL; 1008 } 1009 1010 /* Userspace may decide to perform a ct lookup without a helper 1011 * specified followed by a (recirculate and) commit with one, 1012 * or attach a helper in a later commit. Therefore, for 1013 * connections which we will commit, we may need to attach 1014 * the helper here. 1015 */ 1016 if (info->commit && info->helper && !nfct_help(ct)) { 1017 int err = __nf_ct_try_assign_helper(ct, info->ct, 1018 GFP_ATOMIC); 1019 if (err) 1020 return err; 1021 add_helper = true; 1022 1023 /* helper installed, add seqadj if NAT is required */ 1024 if (info->nat && !nfct_seqadj(ct)) { 1025 if (!nfct_seqadj_ext_add(ct)) 1026 return -EINVAL; 1027 } 1028 } 1029 1030 /* Call the helper only if: 1031 * - nf_conntrack_in() was executed above ("!cached") or a 1032 * helper was just attached ("add_helper") for a confirmed 1033 * connection, or 1034 * - When committing an unconfirmed connection. 1035 */ 1036 if ((nf_ct_is_confirmed(ct) ? !cached || add_helper : 1037 info->commit) && 1038 ovs_ct_helper(skb, info->family) != NF_ACCEPT) { 1039 return -EINVAL; 1040 } 1041 1042 if (nf_ct_protonum(ct) == IPPROTO_TCP && 1043 nf_ct_is_confirmed(ct) && nf_conntrack_tcp_established(ct)) { 1044 /* Be liberal for tcp packets so that out-of-window 1045 * packets are not marked invalid. 1046 */ 1047 nf_ct_set_tcp_be_liberal(ct); 1048 } 1049 } 1050 1051 return 0; 1052 } 1053 1054 /* Lookup connection and read fields into key. */ 1055 static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key, 1056 const struct ovs_conntrack_info *info, 1057 struct sk_buff *skb) 1058 { 1059 struct nf_conntrack_expect *exp; 1060 1061 /* If we pass an expected packet through nf_conntrack_in() the 1062 * expectation is typically removed, but the packet could still be 1063 * lost in upcall processing. To prevent this from happening we 1064 * perform an explicit expectation lookup. Expected connections are 1065 * always new, and will be passed through conntrack only when they are 1066 * committed, as it is OK to remove the expectation at that time. 1067 */ 1068 exp = ovs_ct_expect_find(net, &info->zone, info->family, skb); 1069 if (exp) { 1070 u8 state; 1071 1072 /* NOTE: New connections are NATted and Helped only when 1073 * committed, so we are not calling into NAT here. 1074 */ 1075 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED; 1076 __ovs_ct_update_key(key, state, &info->zone, exp->master); 1077 } else { 1078 struct nf_conn *ct; 1079 int err; 1080 1081 err = __ovs_ct_lookup(net, key, info, skb); 1082 if (err) 1083 return err; 1084 1085 ct = (struct nf_conn *)skb_nfct(skb); 1086 if (ct) 1087 nf_ct_deliver_cached_events(ct); 1088 } 1089 1090 return 0; 1091 } 1092 1093 static bool labels_nonzero(const struct ovs_key_ct_labels *labels) 1094 { 1095 size_t i; 1096 1097 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) 1098 if (labels->ct_labels_32[i]) 1099 return true; 1100 1101 return false; 1102 } 1103 1104 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1105 static struct hlist_head *ct_limit_hash_bucket( 1106 const struct ovs_ct_limit_info *info, u16 zone) 1107 { 1108 return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)]; 1109 } 1110 1111 /* Call with ovs_mutex */ 1112 static void ct_limit_set(const struct ovs_ct_limit_info *info, 1113 struct ovs_ct_limit *new_ct_limit) 1114 { 1115 struct ovs_ct_limit *ct_limit; 1116 struct hlist_head *head; 1117 1118 head = ct_limit_hash_bucket(info, new_ct_limit->zone); 1119 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1120 if (ct_limit->zone == new_ct_limit->zone) { 1121 hlist_replace_rcu(&ct_limit->hlist_node, 1122 &new_ct_limit->hlist_node); 1123 kfree_rcu(ct_limit, rcu); 1124 return; 1125 } 1126 } 1127 1128 hlist_add_head_rcu(&new_ct_limit->hlist_node, head); 1129 } 1130 1131 /* Call with ovs_mutex */ 1132 static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone) 1133 { 1134 struct ovs_ct_limit *ct_limit; 1135 struct hlist_head *head; 1136 struct hlist_node *n; 1137 1138 head = ct_limit_hash_bucket(info, zone); 1139 hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) { 1140 if (ct_limit->zone == zone) { 1141 hlist_del_rcu(&ct_limit->hlist_node); 1142 kfree_rcu(ct_limit, rcu); 1143 return; 1144 } 1145 } 1146 } 1147 1148 /* Call with RCU read lock */ 1149 static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone) 1150 { 1151 struct ovs_ct_limit *ct_limit; 1152 struct hlist_head *head; 1153 1154 head = ct_limit_hash_bucket(info, zone); 1155 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1156 if (ct_limit->zone == zone) 1157 return ct_limit->limit; 1158 } 1159 1160 return info->default_limit; 1161 } 1162 1163 static int ovs_ct_check_limit(struct net *net, 1164 const struct ovs_conntrack_info *info, 1165 const struct nf_conntrack_tuple *tuple) 1166 { 1167 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1168 const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 1169 u32 per_zone_limit, connections; 1170 u32 conncount_key; 1171 1172 conncount_key = info->zone.id; 1173 1174 per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id); 1175 if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED) 1176 return 0; 1177 1178 connections = nf_conncount_count(net, ct_limit_info->data, 1179 &conncount_key, tuple, &info->zone); 1180 if (connections > per_zone_limit) 1181 return -ENOMEM; 1182 1183 return 0; 1184 } 1185 #endif 1186 1187 /* Lookup connection and confirm if unconfirmed. */ 1188 static int ovs_ct_commit(struct net *net, struct sw_flow_key *key, 1189 const struct ovs_conntrack_info *info, 1190 struct sk_buff *skb) 1191 { 1192 enum ip_conntrack_info ctinfo; 1193 struct nf_conn *ct; 1194 int err; 1195 1196 err = __ovs_ct_lookup(net, key, info, skb); 1197 if (err) 1198 return err; 1199 1200 /* The connection could be invalid, in which case this is a no-op.*/ 1201 ct = nf_ct_get(skb, &ctinfo); 1202 if (!ct) 1203 return 0; 1204 1205 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1206 if (static_branch_unlikely(&ovs_ct_limit_enabled)) { 1207 if (!nf_ct_is_confirmed(ct)) { 1208 err = ovs_ct_check_limit(net, info, 1209 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); 1210 if (err) { 1211 net_warn_ratelimited("openvswitch: zone: %u " 1212 "exceeds conntrack limit\n", 1213 info->zone.id); 1214 return err; 1215 } 1216 } 1217 } 1218 #endif 1219 1220 /* Set the conntrack event mask if given. NEW and DELETE events have 1221 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener 1222 * typically would receive many kinds of updates. Setting the event 1223 * mask allows those events to be filtered. The set event mask will 1224 * remain in effect for the lifetime of the connection unless changed 1225 * by a further CT action with both the commit flag and the eventmask 1226 * option. */ 1227 if (info->have_eventmask) { 1228 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct); 1229 1230 if (cache) 1231 cache->ctmask = info->eventmask; 1232 } 1233 1234 /* Apply changes before confirming the connection so that the initial 1235 * conntrack NEW netlink event carries the values given in the CT 1236 * action. 1237 */ 1238 if (info->mark.mask) { 1239 err = ovs_ct_set_mark(ct, key, info->mark.value, 1240 info->mark.mask); 1241 if (err) 1242 return err; 1243 } 1244 if (!nf_ct_is_confirmed(ct)) { 1245 err = ovs_ct_init_labels(ct, key, &info->labels.value, 1246 &info->labels.mask); 1247 if (err) 1248 return err; 1249 } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1250 labels_nonzero(&info->labels.mask)) { 1251 err = ovs_ct_set_labels(ct, key, &info->labels.value, 1252 &info->labels.mask); 1253 if (err) 1254 return err; 1255 } 1256 /* This will take care of sending queued events even if the connection 1257 * is already confirmed. 1258 */ 1259 if (nf_conntrack_confirm(skb) != NF_ACCEPT) 1260 return -EINVAL; 1261 1262 return 0; 1263 } 1264 1265 /* Trim the skb to the length specified by the IP/IPv6 header, 1266 * removing any trailing lower-layer padding. This prepares the skb 1267 * for higher-layer processing that assumes skb->len excludes padding 1268 * (such as nf_ip_checksum). The caller needs to pull the skb to the 1269 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 1270 */ 1271 static int ovs_skb_network_trim(struct sk_buff *skb) 1272 { 1273 unsigned int len; 1274 int err; 1275 1276 switch (skb->protocol) { 1277 case htons(ETH_P_IP): 1278 len = ntohs(ip_hdr(skb)->tot_len); 1279 break; 1280 case htons(ETH_P_IPV6): 1281 len = sizeof(struct ipv6hdr) 1282 + ntohs(ipv6_hdr(skb)->payload_len); 1283 break; 1284 default: 1285 len = skb->len; 1286 } 1287 1288 err = pskb_trim_rcsum(skb, len); 1289 if (err) 1290 kfree_skb(skb); 1291 1292 return err; 1293 } 1294 1295 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero 1296 * value if 'skb' is freed. 1297 */ 1298 int ovs_ct_execute(struct net *net, struct sk_buff *skb, 1299 struct sw_flow_key *key, 1300 const struct ovs_conntrack_info *info) 1301 { 1302 int nh_ofs; 1303 int err; 1304 1305 /* The conntrack module expects to be working at L3. */ 1306 nh_ofs = skb_network_offset(skb); 1307 skb_pull_rcsum(skb, nh_ofs); 1308 1309 err = ovs_skb_network_trim(skb); 1310 if (err) 1311 return err; 1312 1313 if (key->ip.frag != OVS_FRAG_TYPE_NONE) { 1314 err = handle_fragments(net, key, info->zone.id, skb); 1315 if (err) 1316 return err; 1317 } 1318 1319 if (info->commit) 1320 err = ovs_ct_commit(net, key, info, skb); 1321 else 1322 err = ovs_ct_lookup(net, key, info, skb); 1323 1324 skb_push_rcsum(skb, nh_ofs); 1325 if (err) 1326 kfree_skb(skb); 1327 return err; 1328 } 1329 1330 int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key) 1331 { 1332 if (skb_nfct(skb)) { 1333 nf_conntrack_put(skb_nfct(skb)); 1334 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 1335 ovs_ct_fill_key(skb, key, false); 1336 } 1337 1338 return 0; 1339 } 1340 1341 static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name, 1342 const struct sw_flow_key *key, bool log) 1343 { 1344 struct nf_conntrack_helper *helper; 1345 struct nf_conn_help *help; 1346 int ret = 0; 1347 1348 helper = nf_conntrack_helper_try_module_get(name, info->family, 1349 key->ip.proto); 1350 if (!helper) { 1351 OVS_NLERR(log, "Unknown helper \"%s\"", name); 1352 return -EINVAL; 1353 } 1354 1355 help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL); 1356 if (!help) { 1357 nf_conntrack_helper_put(helper); 1358 return -ENOMEM; 1359 } 1360 1361 #if IS_ENABLED(CONFIG_NF_NAT) 1362 if (info->nat) { 1363 ret = nf_nat_helper_try_module_get(name, info->family, 1364 key->ip.proto); 1365 if (ret) { 1366 nf_conntrack_helper_put(helper); 1367 OVS_NLERR(log, "Failed to load \"%s\" NAT helper, error: %d", 1368 name, ret); 1369 return ret; 1370 } 1371 } 1372 #endif 1373 rcu_assign_pointer(help->helper, helper); 1374 info->helper = helper; 1375 return ret; 1376 } 1377 1378 #if IS_ENABLED(CONFIG_NF_NAT) 1379 static int parse_nat(const struct nlattr *attr, 1380 struct ovs_conntrack_info *info, bool log) 1381 { 1382 struct nlattr *a; 1383 int rem; 1384 bool have_ip_max = false; 1385 bool have_proto_max = false; 1386 bool ip_vers = (info->family == NFPROTO_IPV6); 1387 1388 nla_for_each_nested(a, attr, rem) { 1389 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = { 1390 [OVS_NAT_ATTR_SRC] = {0, 0}, 1391 [OVS_NAT_ATTR_DST] = {0, 0}, 1392 [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr), 1393 sizeof(struct in6_addr)}, 1394 [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr), 1395 sizeof(struct in6_addr)}, 1396 [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)}, 1397 [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)}, 1398 [OVS_NAT_ATTR_PERSISTENT] = {0, 0}, 1399 [OVS_NAT_ATTR_PROTO_HASH] = {0, 0}, 1400 [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0}, 1401 }; 1402 int type = nla_type(a); 1403 1404 if (type > OVS_NAT_ATTR_MAX) { 1405 OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)", 1406 type, OVS_NAT_ATTR_MAX); 1407 return -EINVAL; 1408 } 1409 1410 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) { 1411 OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)", 1412 type, nla_len(a), 1413 ovs_nat_attr_lens[type][ip_vers]); 1414 return -EINVAL; 1415 } 1416 1417 switch (type) { 1418 case OVS_NAT_ATTR_SRC: 1419 case OVS_NAT_ATTR_DST: 1420 if (info->nat) { 1421 OVS_NLERR(log, "Only one type of NAT may be specified"); 1422 return -ERANGE; 1423 } 1424 info->nat |= OVS_CT_NAT; 1425 info->nat |= ((type == OVS_NAT_ATTR_SRC) 1426 ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT); 1427 break; 1428 1429 case OVS_NAT_ATTR_IP_MIN: 1430 nla_memcpy(&info->range.min_addr, a, 1431 sizeof(info->range.min_addr)); 1432 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1433 break; 1434 1435 case OVS_NAT_ATTR_IP_MAX: 1436 have_ip_max = true; 1437 nla_memcpy(&info->range.max_addr, a, 1438 sizeof(info->range.max_addr)); 1439 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1440 break; 1441 1442 case OVS_NAT_ATTR_PROTO_MIN: 1443 info->range.min_proto.all = htons(nla_get_u16(a)); 1444 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1445 break; 1446 1447 case OVS_NAT_ATTR_PROTO_MAX: 1448 have_proto_max = true; 1449 info->range.max_proto.all = htons(nla_get_u16(a)); 1450 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1451 break; 1452 1453 case OVS_NAT_ATTR_PERSISTENT: 1454 info->range.flags |= NF_NAT_RANGE_PERSISTENT; 1455 break; 1456 1457 case OVS_NAT_ATTR_PROTO_HASH: 1458 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM; 1459 break; 1460 1461 case OVS_NAT_ATTR_PROTO_RANDOM: 1462 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY; 1463 break; 1464 1465 default: 1466 OVS_NLERR(log, "Unknown nat attribute (%d)", type); 1467 return -EINVAL; 1468 } 1469 } 1470 1471 if (rem > 0) { 1472 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem); 1473 return -EINVAL; 1474 } 1475 if (!info->nat) { 1476 /* Do not allow flags if no type is given. */ 1477 if (info->range.flags) { 1478 OVS_NLERR(log, 1479 "NAT flags may be given only when NAT range (SRC or DST) is also specified." 1480 ); 1481 return -EINVAL; 1482 } 1483 info->nat = OVS_CT_NAT; /* NAT existing connections. */ 1484 } else if (!info->commit) { 1485 OVS_NLERR(log, 1486 "NAT attributes may be specified only when CT COMMIT flag is also specified." 1487 ); 1488 return -EINVAL; 1489 } 1490 /* Allow missing IP_MAX. */ 1491 if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) { 1492 memcpy(&info->range.max_addr, &info->range.min_addr, 1493 sizeof(info->range.max_addr)); 1494 } 1495 /* Allow missing PROTO_MAX. */ 1496 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1497 !have_proto_max) { 1498 info->range.max_proto.all = info->range.min_proto.all; 1499 } 1500 return 0; 1501 } 1502 #endif 1503 1504 static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = { 1505 [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1506 [OVS_CT_ATTR_FORCE_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1507 [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16), 1508 .maxlen = sizeof(u16) }, 1509 [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark), 1510 .maxlen = sizeof(struct md_mark) }, 1511 [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels), 1512 .maxlen = sizeof(struct md_labels) }, 1513 [OVS_CT_ATTR_HELPER] = { .minlen = 1, 1514 .maxlen = NF_CT_HELPER_NAME_LEN }, 1515 #if IS_ENABLED(CONFIG_NF_NAT) 1516 /* NAT length is checked when parsing the nested attributes. */ 1517 [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX }, 1518 #endif 1519 [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32), 1520 .maxlen = sizeof(u32) }, 1521 [OVS_CT_ATTR_TIMEOUT] = { .minlen = 1, 1522 .maxlen = CTNL_TIMEOUT_NAME_MAX }, 1523 }; 1524 1525 static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info, 1526 const char **helper, bool log) 1527 { 1528 struct nlattr *a; 1529 int rem; 1530 1531 nla_for_each_nested(a, attr, rem) { 1532 int type = nla_type(a); 1533 int maxlen; 1534 int minlen; 1535 1536 if (type > OVS_CT_ATTR_MAX) { 1537 OVS_NLERR(log, 1538 "Unknown conntrack attr (type=%d, max=%d)", 1539 type, OVS_CT_ATTR_MAX); 1540 return -EINVAL; 1541 } 1542 1543 maxlen = ovs_ct_attr_lens[type].maxlen; 1544 minlen = ovs_ct_attr_lens[type].minlen; 1545 if (nla_len(a) < minlen || nla_len(a) > maxlen) { 1546 OVS_NLERR(log, 1547 "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)", 1548 type, nla_len(a), maxlen); 1549 return -EINVAL; 1550 } 1551 1552 switch (type) { 1553 case OVS_CT_ATTR_FORCE_COMMIT: 1554 info->force = true; 1555 fallthrough; 1556 case OVS_CT_ATTR_COMMIT: 1557 info->commit = true; 1558 break; 1559 #ifdef CONFIG_NF_CONNTRACK_ZONES 1560 case OVS_CT_ATTR_ZONE: 1561 info->zone.id = nla_get_u16(a); 1562 break; 1563 #endif 1564 #ifdef CONFIG_NF_CONNTRACK_MARK 1565 case OVS_CT_ATTR_MARK: { 1566 struct md_mark *mark = nla_data(a); 1567 1568 if (!mark->mask) { 1569 OVS_NLERR(log, "ct_mark mask cannot be 0"); 1570 return -EINVAL; 1571 } 1572 info->mark = *mark; 1573 break; 1574 } 1575 #endif 1576 #ifdef CONFIG_NF_CONNTRACK_LABELS 1577 case OVS_CT_ATTR_LABELS: { 1578 struct md_labels *labels = nla_data(a); 1579 1580 if (!labels_nonzero(&labels->mask)) { 1581 OVS_NLERR(log, "ct_labels mask cannot be 0"); 1582 return -EINVAL; 1583 } 1584 info->labels = *labels; 1585 break; 1586 } 1587 #endif 1588 case OVS_CT_ATTR_HELPER: 1589 *helper = nla_data(a); 1590 if (!memchr(*helper, '\0', nla_len(a))) { 1591 OVS_NLERR(log, "Invalid conntrack helper"); 1592 return -EINVAL; 1593 } 1594 break; 1595 #if IS_ENABLED(CONFIG_NF_NAT) 1596 case OVS_CT_ATTR_NAT: { 1597 int err = parse_nat(a, info, log); 1598 1599 if (err) 1600 return err; 1601 break; 1602 } 1603 #endif 1604 case OVS_CT_ATTR_EVENTMASK: 1605 info->have_eventmask = true; 1606 info->eventmask = nla_get_u32(a); 1607 break; 1608 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 1609 case OVS_CT_ATTR_TIMEOUT: 1610 memcpy(info->timeout, nla_data(a), nla_len(a)); 1611 if (!memchr(info->timeout, '\0', nla_len(a))) { 1612 OVS_NLERR(log, "Invalid conntrack timeout"); 1613 return -EINVAL; 1614 } 1615 break; 1616 #endif 1617 1618 default: 1619 OVS_NLERR(log, "Unknown conntrack attr (%d)", 1620 type); 1621 return -EINVAL; 1622 } 1623 } 1624 1625 #ifdef CONFIG_NF_CONNTRACK_MARK 1626 if (!info->commit && info->mark.mask) { 1627 OVS_NLERR(log, 1628 "Setting conntrack mark requires 'commit' flag."); 1629 return -EINVAL; 1630 } 1631 #endif 1632 #ifdef CONFIG_NF_CONNTRACK_LABELS 1633 if (!info->commit && labels_nonzero(&info->labels.mask)) { 1634 OVS_NLERR(log, 1635 "Setting conntrack labels requires 'commit' flag."); 1636 return -EINVAL; 1637 } 1638 #endif 1639 if (rem > 0) { 1640 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem); 1641 return -EINVAL; 1642 } 1643 1644 return 0; 1645 } 1646 1647 bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr) 1648 { 1649 if (attr == OVS_KEY_ATTR_CT_STATE) 1650 return true; 1651 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1652 attr == OVS_KEY_ATTR_CT_ZONE) 1653 return true; 1654 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1655 attr == OVS_KEY_ATTR_CT_MARK) 1656 return true; 1657 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1658 attr == OVS_KEY_ATTR_CT_LABELS) { 1659 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1660 1661 return ovs_net->xt_label; 1662 } 1663 1664 return false; 1665 } 1666 1667 int ovs_ct_copy_action(struct net *net, const struct nlattr *attr, 1668 const struct sw_flow_key *key, 1669 struct sw_flow_actions **sfa, bool log) 1670 { 1671 struct ovs_conntrack_info ct_info; 1672 const char *helper = NULL; 1673 u16 family; 1674 int err; 1675 1676 family = key_to_nfproto(key); 1677 if (family == NFPROTO_UNSPEC) { 1678 OVS_NLERR(log, "ct family unspecified"); 1679 return -EINVAL; 1680 } 1681 1682 memset(&ct_info, 0, sizeof(ct_info)); 1683 ct_info.family = family; 1684 1685 nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID, 1686 NF_CT_DEFAULT_ZONE_DIR, 0); 1687 1688 err = parse_ct(attr, &ct_info, &helper, log); 1689 if (err) 1690 return err; 1691 1692 /* Set up template for tracking connections in specific zones. */ 1693 ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL); 1694 if (!ct_info.ct) { 1695 OVS_NLERR(log, "Failed to allocate conntrack template"); 1696 return -ENOMEM; 1697 } 1698 1699 if (ct_info.timeout[0]) { 1700 if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto, 1701 ct_info.timeout)) 1702 pr_info_ratelimited("Failed to associated timeout " 1703 "policy `%s'\n", ct_info.timeout); 1704 else 1705 ct_info.nf_ct_timeout = rcu_dereference( 1706 nf_ct_timeout_find(ct_info.ct)->timeout); 1707 1708 } 1709 1710 if (helper) { 1711 err = ovs_ct_add_helper(&ct_info, helper, key, log); 1712 if (err) 1713 goto err_free_ct; 1714 } 1715 1716 err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info, 1717 sizeof(ct_info), log); 1718 if (err) 1719 goto err_free_ct; 1720 1721 __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status); 1722 nf_conntrack_get(&ct_info.ct->ct_general); 1723 return 0; 1724 err_free_ct: 1725 __ovs_ct_free_action(&ct_info); 1726 return err; 1727 } 1728 1729 #if IS_ENABLED(CONFIG_NF_NAT) 1730 static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, 1731 struct sk_buff *skb) 1732 { 1733 struct nlattr *start; 1734 1735 start = nla_nest_start_noflag(skb, OVS_CT_ATTR_NAT); 1736 if (!start) 1737 return false; 1738 1739 if (info->nat & OVS_CT_SRC_NAT) { 1740 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC)) 1741 return false; 1742 } else if (info->nat & OVS_CT_DST_NAT) { 1743 if (nla_put_flag(skb, OVS_NAT_ATTR_DST)) 1744 return false; 1745 } else { 1746 goto out; 1747 } 1748 1749 if (info->range.flags & NF_NAT_RANGE_MAP_IPS) { 1750 if (IS_ENABLED(CONFIG_NF_NAT) && 1751 info->family == NFPROTO_IPV4) { 1752 if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN, 1753 info->range.min_addr.ip) || 1754 (info->range.max_addr.ip 1755 != info->range.min_addr.ip && 1756 (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX, 1757 info->range.max_addr.ip)))) 1758 return false; 1759 } else if (IS_ENABLED(CONFIG_IPV6) && 1760 info->family == NFPROTO_IPV6) { 1761 if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN, 1762 &info->range.min_addr.in6) || 1763 (memcmp(&info->range.max_addr.in6, 1764 &info->range.min_addr.in6, 1765 sizeof(info->range.max_addr.in6)) && 1766 (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX, 1767 &info->range.max_addr.in6)))) 1768 return false; 1769 } else { 1770 return false; 1771 } 1772 } 1773 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1774 (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN, 1775 ntohs(info->range.min_proto.all)) || 1776 (info->range.max_proto.all != info->range.min_proto.all && 1777 nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX, 1778 ntohs(info->range.max_proto.all))))) 1779 return false; 1780 1781 if (info->range.flags & NF_NAT_RANGE_PERSISTENT && 1782 nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT)) 1783 return false; 1784 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM && 1785 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH)) 1786 return false; 1787 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY && 1788 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM)) 1789 return false; 1790 out: 1791 nla_nest_end(skb, start); 1792 1793 return true; 1794 } 1795 #endif 1796 1797 int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info, 1798 struct sk_buff *skb) 1799 { 1800 struct nlattr *start; 1801 1802 start = nla_nest_start_noflag(skb, OVS_ACTION_ATTR_CT); 1803 if (!start) 1804 return -EMSGSIZE; 1805 1806 if (ct_info->commit && nla_put_flag(skb, ct_info->force 1807 ? OVS_CT_ATTR_FORCE_COMMIT 1808 : OVS_CT_ATTR_COMMIT)) 1809 return -EMSGSIZE; 1810 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1811 nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id)) 1812 return -EMSGSIZE; 1813 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask && 1814 nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark), 1815 &ct_info->mark)) 1816 return -EMSGSIZE; 1817 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1818 labels_nonzero(&ct_info->labels.mask) && 1819 nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels), 1820 &ct_info->labels)) 1821 return -EMSGSIZE; 1822 if (ct_info->helper) { 1823 if (nla_put_string(skb, OVS_CT_ATTR_HELPER, 1824 ct_info->helper->name)) 1825 return -EMSGSIZE; 1826 } 1827 if (ct_info->have_eventmask && 1828 nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask)) 1829 return -EMSGSIZE; 1830 if (ct_info->timeout[0]) { 1831 if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout)) 1832 return -EMSGSIZE; 1833 } 1834 1835 #if IS_ENABLED(CONFIG_NF_NAT) 1836 if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb)) 1837 return -EMSGSIZE; 1838 #endif 1839 nla_nest_end(skb, start); 1840 1841 return 0; 1842 } 1843 1844 void ovs_ct_free_action(const struct nlattr *a) 1845 { 1846 struct ovs_conntrack_info *ct_info = nla_data(a); 1847 1848 __ovs_ct_free_action(ct_info); 1849 } 1850 1851 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info) 1852 { 1853 if (ct_info->helper) { 1854 #if IS_ENABLED(CONFIG_NF_NAT) 1855 if (ct_info->nat) 1856 nf_nat_helper_put(ct_info->helper); 1857 #endif 1858 nf_conntrack_helper_put(ct_info->helper); 1859 } 1860 if (ct_info->ct) { 1861 if (ct_info->timeout[0]) 1862 nf_ct_destroy_timeout(ct_info->ct); 1863 nf_ct_tmpl_free(ct_info->ct); 1864 } 1865 } 1866 1867 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1868 static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net) 1869 { 1870 int i, err; 1871 1872 ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info), 1873 GFP_KERNEL); 1874 if (!ovs_net->ct_limit_info) 1875 return -ENOMEM; 1876 1877 ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT; 1878 ovs_net->ct_limit_info->limits = 1879 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head), 1880 GFP_KERNEL); 1881 if (!ovs_net->ct_limit_info->limits) { 1882 kfree(ovs_net->ct_limit_info); 1883 return -ENOMEM; 1884 } 1885 1886 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++) 1887 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]); 1888 1889 ovs_net->ct_limit_info->data = 1890 nf_conncount_init(net, NFPROTO_INET, sizeof(u32)); 1891 1892 if (IS_ERR(ovs_net->ct_limit_info->data)) { 1893 err = PTR_ERR(ovs_net->ct_limit_info->data); 1894 kfree(ovs_net->ct_limit_info->limits); 1895 kfree(ovs_net->ct_limit_info); 1896 pr_err("openvswitch: failed to init nf_conncount %d\n", err); 1897 return err; 1898 } 1899 return 0; 1900 } 1901 1902 static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net) 1903 { 1904 const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info; 1905 int i; 1906 1907 nf_conncount_destroy(net, NFPROTO_INET, info->data); 1908 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 1909 struct hlist_head *head = &info->limits[i]; 1910 struct ovs_ct_limit *ct_limit; 1911 1912 hlist_for_each_entry_rcu(ct_limit, head, hlist_node, 1913 lockdep_ovsl_is_held()) 1914 kfree_rcu(ct_limit, rcu); 1915 } 1916 kfree(info->limits); 1917 kfree(info); 1918 } 1919 1920 static struct sk_buff * 1921 ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd, 1922 struct ovs_header **ovs_reply_header) 1923 { 1924 struct ovs_header *ovs_header = info->userhdr; 1925 struct sk_buff *skb; 1926 1927 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1928 if (!skb) 1929 return ERR_PTR(-ENOMEM); 1930 1931 *ovs_reply_header = genlmsg_put(skb, info->snd_portid, 1932 info->snd_seq, 1933 &dp_ct_limit_genl_family, 0, cmd); 1934 1935 if (!*ovs_reply_header) { 1936 nlmsg_free(skb); 1937 return ERR_PTR(-EMSGSIZE); 1938 } 1939 (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex; 1940 1941 return skb; 1942 } 1943 1944 static bool check_zone_id(int zone_id, u16 *pzone) 1945 { 1946 if (zone_id >= 0 && zone_id <= 65535) { 1947 *pzone = (u16)zone_id; 1948 return true; 1949 } 1950 return false; 1951 } 1952 1953 static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit, 1954 struct ovs_ct_limit_info *info) 1955 { 1956 struct ovs_zone_limit *zone_limit; 1957 int rem; 1958 u16 zone; 1959 1960 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1961 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1962 1963 while (rem >= sizeof(*zone_limit)) { 1964 if (unlikely(zone_limit->zone_id == 1965 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1966 ovs_lock(); 1967 info->default_limit = zone_limit->limit; 1968 ovs_unlock(); 1969 } else if (unlikely(!check_zone_id( 1970 zone_limit->zone_id, &zone))) { 1971 OVS_NLERR(true, "zone id is out of range"); 1972 } else { 1973 struct ovs_ct_limit *ct_limit; 1974 1975 ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL); 1976 if (!ct_limit) 1977 return -ENOMEM; 1978 1979 ct_limit->zone = zone; 1980 ct_limit->limit = zone_limit->limit; 1981 1982 ovs_lock(); 1983 ct_limit_set(info, ct_limit); 1984 ovs_unlock(); 1985 } 1986 rem -= NLA_ALIGN(sizeof(*zone_limit)); 1987 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 1988 NLA_ALIGN(sizeof(*zone_limit))); 1989 } 1990 1991 if (rem) 1992 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem); 1993 1994 return 0; 1995 } 1996 1997 static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit, 1998 struct ovs_ct_limit_info *info) 1999 { 2000 struct ovs_zone_limit *zone_limit; 2001 int rem; 2002 u16 zone; 2003 2004 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 2005 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 2006 2007 while (rem >= sizeof(*zone_limit)) { 2008 if (unlikely(zone_limit->zone_id == 2009 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 2010 ovs_lock(); 2011 info->default_limit = OVS_CT_LIMIT_DEFAULT; 2012 ovs_unlock(); 2013 } else if (unlikely(!check_zone_id( 2014 zone_limit->zone_id, &zone))) { 2015 OVS_NLERR(true, "zone id is out of range"); 2016 } else { 2017 ovs_lock(); 2018 ct_limit_del(info, zone); 2019 ovs_unlock(); 2020 } 2021 rem -= NLA_ALIGN(sizeof(*zone_limit)); 2022 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 2023 NLA_ALIGN(sizeof(*zone_limit))); 2024 } 2025 2026 if (rem) 2027 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem); 2028 2029 return 0; 2030 } 2031 2032 static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info, 2033 struct sk_buff *reply) 2034 { 2035 struct ovs_zone_limit zone_limit = { 2036 .zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE, 2037 .limit = info->default_limit, 2038 }; 2039 2040 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 2041 } 2042 2043 static int __ovs_ct_limit_get_zone_limit(struct net *net, 2044 struct nf_conncount_data *data, 2045 u16 zone_id, u32 limit, 2046 struct sk_buff *reply) 2047 { 2048 struct nf_conntrack_zone ct_zone; 2049 struct ovs_zone_limit zone_limit; 2050 u32 conncount_key = zone_id; 2051 2052 zone_limit.zone_id = zone_id; 2053 zone_limit.limit = limit; 2054 nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0); 2055 2056 zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL, 2057 &ct_zone); 2058 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 2059 } 2060 2061 static int ovs_ct_limit_get_zone_limit(struct net *net, 2062 struct nlattr *nla_zone_limit, 2063 struct ovs_ct_limit_info *info, 2064 struct sk_buff *reply) 2065 { 2066 struct ovs_zone_limit *zone_limit; 2067 int rem, err; 2068 u32 limit; 2069 u16 zone; 2070 2071 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 2072 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 2073 2074 while (rem >= sizeof(*zone_limit)) { 2075 if (unlikely(zone_limit->zone_id == 2076 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 2077 err = ovs_ct_limit_get_default_limit(info, reply); 2078 if (err) 2079 return err; 2080 } else if (unlikely(!check_zone_id(zone_limit->zone_id, 2081 &zone))) { 2082 OVS_NLERR(true, "zone id is out of range"); 2083 } else { 2084 rcu_read_lock(); 2085 limit = ct_limit_get(info, zone); 2086 rcu_read_unlock(); 2087 2088 err = __ovs_ct_limit_get_zone_limit( 2089 net, info->data, zone, limit, reply); 2090 if (err) 2091 return err; 2092 } 2093 rem -= NLA_ALIGN(sizeof(*zone_limit)); 2094 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 2095 NLA_ALIGN(sizeof(*zone_limit))); 2096 } 2097 2098 if (rem) 2099 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem); 2100 2101 return 0; 2102 } 2103 2104 static int ovs_ct_limit_get_all_zone_limit(struct net *net, 2105 struct ovs_ct_limit_info *info, 2106 struct sk_buff *reply) 2107 { 2108 struct ovs_ct_limit *ct_limit; 2109 struct hlist_head *head; 2110 int i, err = 0; 2111 2112 err = ovs_ct_limit_get_default_limit(info, reply); 2113 if (err) 2114 return err; 2115 2116 rcu_read_lock(); 2117 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 2118 head = &info->limits[i]; 2119 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 2120 err = __ovs_ct_limit_get_zone_limit(net, info->data, 2121 ct_limit->zone, ct_limit->limit, reply); 2122 if (err) 2123 goto exit_err; 2124 } 2125 } 2126 2127 exit_err: 2128 rcu_read_unlock(); 2129 return err; 2130 } 2131 2132 static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info) 2133 { 2134 struct nlattr **a = info->attrs; 2135 struct sk_buff *reply; 2136 struct ovs_header *ovs_reply_header; 2137 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2138 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2139 int err; 2140 2141 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET, 2142 &ovs_reply_header); 2143 if (IS_ERR(reply)) 2144 return PTR_ERR(reply); 2145 2146 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2147 err = -EINVAL; 2148 goto exit_err; 2149 } 2150 2151 err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2152 ct_limit_info); 2153 if (err) 2154 goto exit_err; 2155 2156 static_branch_enable(&ovs_ct_limit_enabled); 2157 2158 genlmsg_end(reply, ovs_reply_header); 2159 return genlmsg_reply(reply, info); 2160 2161 exit_err: 2162 nlmsg_free(reply); 2163 return err; 2164 } 2165 2166 static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info) 2167 { 2168 struct nlattr **a = info->attrs; 2169 struct sk_buff *reply; 2170 struct ovs_header *ovs_reply_header; 2171 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2172 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2173 int err; 2174 2175 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL, 2176 &ovs_reply_header); 2177 if (IS_ERR(reply)) 2178 return PTR_ERR(reply); 2179 2180 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2181 err = -EINVAL; 2182 goto exit_err; 2183 } 2184 2185 err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2186 ct_limit_info); 2187 if (err) 2188 goto exit_err; 2189 2190 genlmsg_end(reply, ovs_reply_header); 2191 return genlmsg_reply(reply, info); 2192 2193 exit_err: 2194 nlmsg_free(reply); 2195 return err; 2196 } 2197 2198 static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info) 2199 { 2200 struct nlattr **a = info->attrs; 2201 struct nlattr *nla_reply; 2202 struct sk_buff *reply; 2203 struct ovs_header *ovs_reply_header; 2204 struct net *net = sock_net(skb->sk); 2205 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2206 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2207 int err; 2208 2209 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET, 2210 &ovs_reply_header); 2211 if (IS_ERR(reply)) 2212 return PTR_ERR(reply); 2213 2214 nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT); 2215 if (!nla_reply) { 2216 err = -EMSGSIZE; 2217 goto exit_err; 2218 } 2219 2220 if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2221 err = ovs_ct_limit_get_zone_limit( 2222 net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info, 2223 reply); 2224 if (err) 2225 goto exit_err; 2226 } else { 2227 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info, 2228 reply); 2229 if (err) 2230 goto exit_err; 2231 } 2232 2233 nla_nest_end(reply, nla_reply); 2234 genlmsg_end(reply, ovs_reply_header); 2235 return genlmsg_reply(reply, info); 2236 2237 exit_err: 2238 nlmsg_free(reply); 2239 return err; 2240 } 2241 2242 static const struct genl_small_ops ct_limit_genl_ops[] = { 2243 { .cmd = OVS_CT_LIMIT_CMD_SET, 2244 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2245 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2246 * privilege. */ 2247 .doit = ovs_ct_limit_cmd_set, 2248 }, 2249 { .cmd = OVS_CT_LIMIT_CMD_DEL, 2250 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2251 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2252 * privilege. */ 2253 .doit = ovs_ct_limit_cmd_del, 2254 }, 2255 { .cmd = OVS_CT_LIMIT_CMD_GET, 2256 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2257 .flags = 0, /* OK for unprivileged users. */ 2258 .doit = ovs_ct_limit_cmd_get, 2259 }, 2260 }; 2261 2262 static const struct genl_multicast_group ovs_ct_limit_multicast_group = { 2263 .name = OVS_CT_LIMIT_MCGROUP, 2264 }; 2265 2266 struct genl_family dp_ct_limit_genl_family __ro_after_init = { 2267 .hdrsize = sizeof(struct ovs_header), 2268 .name = OVS_CT_LIMIT_FAMILY, 2269 .version = OVS_CT_LIMIT_VERSION, 2270 .maxattr = OVS_CT_LIMIT_ATTR_MAX, 2271 .policy = ct_limit_policy, 2272 .netnsok = true, 2273 .parallel_ops = true, 2274 .small_ops = ct_limit_genl_ops, 2275 .n_small_ops = ARRAY_SIZE(ct_limit_genl_ops), 2276 .mcgrps = &ovs_ct_limit_multicast_group, 2277 .n_mcgrps = 1, 2278 .module = THIS_MODULE, 2279 }; 2280 #endif 2281 2282 int ovs_ct_init(struct net *net) 2283 { 2284 unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE; 2285 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2286 2287 if (nf_connlabels_get(net, n_bits - 1)) { 2288 ovs_net->xt_label = false; 2289 OVS_NLERR(true, "Failed to set connlabel length"); 2290 } else { 2291 ovs_net->xt_label = true; 2292 } 2293 2294 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2295 return ovs_ct_limit_init(net, ovs_net); 2296 #else 2297 return 0; 2298 #endif 2299 } 2300 2301 void ovs_ct_exit(struct net *net) 2302 { 2303 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2304 2305 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2306 ovs_ct_limit_exit(net, ovs_net); 2307 #endif 2308 2309 if (ovs_net->xt_label) 2310 nf_connlabels_put(net); 2311 } 2312