1 /* 2 * Copyright (c) 2015 Nicira, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of version 2 of the GNU General Public 6 * License as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 11 * General Public License for more details. 12 */ 13 14 #include <linux/module.h> 15 #include <linux/openvswitch.h> 16 #include <linux/tcp.h> 17 #include <linux/udp.h> 18 #include <linux/sctp.h> 19 #include <linux/static_key.h> 20 #include <net/ip.h> 21 #include <net/genetlink.h> 22 #include <net/netfilter/nf_conntrack_core.h> 23 #include <net/netfilter/nf_conntrack_count.h> 24 #include <net/netfilter/nf_conntrack_helper.h> 25 #include <net/netfilter/nf_conntrack_labels.h> 26 #include <net/netfilter/nf_conntrack_seqadj.h> 27 #include <net/netfilter/nf_conntrack_timeout.h> 28 #include <net/netfilter/nf_conntrack_zones.h> 29 #include <net/netfilter/ipv6/nf_defrag_ipv6.h> 30 #include <net/ipv6_frag.h> 31 32 #if IS_ENABLED(CONFIG_NF_NAT) 33 #include <net/netfilter/nf_nat.h> 34 #endif 35 36 #include "datapath.h" 37 #include "conntrack.h" 38 #include "flow.h" 39 #include "flow_netlink.h" 40 41 struct ovs_ct_len_tbl { 42 int maxlen; 43 int minlen; 44 }; 45 46 /* Metadata mark for masked write to conntrack mark */ 47 struct md_mark { 48 u32 value; 49 u32 mask; 50 }; 51 52 /* Metadata label for masked write to conntrack label. */ 53 struct md_labels { 54 struct ovs_key_ct_labels value; 55 struct ovs_key_ct_labels mask; 56 }; 57 58 enum ovs_ct_nat { 59 OVS_CT_NAT = 1 << 0, /* NAT for committed connections only. */ 60 OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */ 61 OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */ 62 }; 63 64 /* Conntrack action context for execution. */ 65 struct ovs_conntrack_info { 66 struct nf_conntrack_helper *helper; 67 struct nf_conntrack_zone zone; 68 struct nf_conn *ct; 69 u8 commit : 1; 70 u8 nat : 3; /* enum ovs_ct_nat */ 71 u8 force : 1; 72 u8 have_eventmask : 1; 73 u16 family; 74 u32 eventmask; /* Mask of 1 << IPCT_*. */ 75 struct md_mark mark; 76 struct md_labels labels; 77 char timeout[CTNL_TIMEOUT_NAME_MAX]; 78 #if IS_ENABLED(CONFIG_NF_NAT) 79 struct nf_nat_range2 range; /* Only present for SRC NAT and DST NAT. */ 80 #endif 81 }; 82 83 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 84 #define OVS_CT_LIMIT_UNLIMITED 0 85 #define OVS_CT_LIMIT_DEFAULT OVS_CT_LIMIT_UNLIMITED 86 #define CT_LIMIT_HASH_BUCKETS 512 87 static DEFINE_STATIC_KEY_FALSE(ovs_ct_limit_enabled); 88 89 struct ovs_ct_limit { 90 /* Elements in ovs_ct_limit_info->limits hash table */ 91 struct hlist_node hlist_node; 92 struct rcu_head rcu; 93 u16 zone; 94 u32 limit; 95 }; 96 97 struct ovs_ct_limit_info { 98 u32 default_limit; 99 struct hlist_head *limits; 100 struct nf_conncount_data *data; 101 }; 102 103 static const struct nla_policy ct_limit_policy[OVS_CT_LIMIT_ATTR_MAX + 1] = { 104 [OVS_CT_LIMIT_ATTR_ZONE_LIMIT] = { .type = NLA_NESTED, }, 105 }; 106 #endif 107 108 static bool labels_nonzero(const struct ovs_key_ct_labels *labels); 109 110 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info); 111 112 static u16 key_to_nfproto(const struct sw_flow_key *key) 113 { 114 switch (ntohs(key->eth.type)) { 115 case ETH_P_IP: 116 return NFPROTO_IPV4; 117 case ETH_P_IPV6: 118 return NFPROTO_IPV6; 119 default: 120 return NFPROTO_UNSPEC; 121 } 122 } 123 124 /* Map SKB connection state into the values used by flow definition. */ 125 static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo) 126 { 127 u8 ct_state = OVS_CS_F_TRACKED; 128 129 switch (ctinfo) { 130 case IP_CT_ESTABLISHED_REPLY: 131 case IP_CT_RELATED_REPLY: 132 ct_state |= OVS_CS_F_REPLY_DIR; 133 break; 134 default: 135 break; 136 } 137 138 switch (ctinfo) { 139 case IP_CT_ESTABLISHED: 140 case IP_CT_ESTABLISHED_REPLY: 141 ct_state |= OVS_CS_F_ESTABLISHED; 142 break; 143 case IP_CT_RELATED: 144 case IP_CT_RELATED_REPLY: 145 ct_state |= OVS_CS_F_RELATED; 146 break; 147 case IP_CT_NEW: 148 ct_state |= OVS_CS_F_NEW; 149 break; 150 default: 151 break; 152 } 153 154 return ct_state; 155 } 156 157 static u32 ovs_ct_get_mark(const struct nf_conn *ct) 158 { 159 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 160 return ct ? ct->mark : 0; 161 #else 162 return 0; 163 #endif 164 } 165 166 /* Guard against conntrack labels max size shrinking below 128 bits. */ 167 #if NF_CT_LABELS_MAX_SIZE < 16 168 #error NF_CT_LABELS_MAX_SIZE must be at least 16 bytes 169 #endif 170 171 static void ovs_ct_get_labels(const struct nf_conn *ct, 172 struct ovs_key_ct_labels *labels) 173 { 174 struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL; 175 176 if (cl) 177 memcpy(labels, cl->bits, OVS_CT_LABELS_LEN); 178 else 179 memset(labels, 0, OVS_CT_LABELS_LEN); 180 } 181 182 static void __ovs_ct_update_key_orig_tp(struct sw_flow_key *key, 183 const struct nf_conntrack_tuple *orig, 184 u8 icmp_proto) 185 { 186 key->ct_orig_proto = orig->dst.protonum; 187 if (orig->dst.protonum == icmp_proto) { 188 key->ct.orig_tp.src = htons(orig->dst.u.icmp.type); 189 key->ct.orig_tp.dst = htons(orig->dst.u.icmp.code); 190 } else { 191 key->ct.orig_tp.src = orig->src.u.all; 192 key->ct.orig_tp.dst = orig->dst.u.all; 193 } 194 } 195 196 static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state, 197 const struct nf_conntrack_zone *zone, 198 const struct nf_conn *ct) 199 { 200 key->ct_state = state; 201 key->ct_zone = zone->id; 202 key->ct.mark = ovs_ct_get_mark(ct); 203 ovs_ct_get_labels(ct, &key->ct.labels); 204 205 if (ct) { 206 const struct nf_conntrack_tuple *orig; 207 208 /* Use the master if we have one. */ 209 if (ct->master) 210 ct = ct->master; 211 orig = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple; 212 213 /* IP version must match with the master connection. */ 214 if (key->eth.type == htons(ETH_P_IP) && 215 nf_ct_l3num(ct) == NFPROTO_IPV4) { 216 key->ipv4.ct_orig.src = orig->src.u3.ip; 217 key->ipv4.ct_orig.dst = orig->dst.u3.ip; 218 __ovs_ct_update_key_orig_tp(key, orig, IPPROTO_ICMP); 219 return; 220 } else if (key->eth.type == htons(ETH_P_IPV6) && 221 !sw_flow_key_is_nd(key) && 222 nf_ct_l3num(ct) == NFPROTO_IPV6) { 223 key->ipv6.ct_orig.src = orig->src.u3.in6; 224 key->ipv6.ct_orig.dst = orig->dst.u3.in6; 225 __ovs_ct_update_key_orig_tp(key, orig, NEXTHDR_ICMP); 226 return; 227 } 228 } 229 /* Clear 'ct_orig_proto' to mark the non-existence of conntrack 230 * original direction key fields. 231 */ 232 key->ct_orig_proto = 0; 233 } 234 235 /* Update 'key' based on skb->_nfct. If 'post_ct' is true, then OVS has 236 * previously sent the packet to conntrack via the ct action. If 237 * 'keep_nat_flags' is true, the existing NAT flags retained, else they are 238 * initialized from the connection status. 239 */ 240 static void ovs_ct_update_key(const struct sk_buff *skb, 241 const struct ovs_conntrack_info *info, 242 struct sw_flow_key *key, bool post_ct, 243 bool keep_nat_flags) 244 { 245 const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt; 246 enum ip_conntrack_info ctinfo; 247 struct nf_conn *ct; 248 u8 state = 0; 249 250 ct = nf_ct_get(skb, &ctinfo); 251 if (ct) { 252 state = ovs_ct_get_state(ctinfo); 253 /* All unconfirmed entries are NEW connections. */ 254 if (!nf_ct_is_confirmed(ct)) 255 state |= OVS_CS_F_NEW; 256 /* OVS persists the related flag for the duration of the 257 * connection. 258 */ 259 if (ct->master) 260 state |= OVS_CS_F_RELATED; 261 if (keep_nat_flags) { 262 state |= key->ct_state & OVS_CS_F_NAT_MASK; 263 } else { 264 if (ct->status & IPS_SRC_NAT) 265 state |= OVS_CS_F_SRC_NAT; 266 if (ct->status & IPS_DST_NAT) 267 state |= OVS_CS_F_DST_NAT; 268 } 269 zone = nf_ct_zone(ct); 270 } else if (post_ct) { 271 state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID; 272 if (info) 273 zone = &info->zone; 274 } 275 __ovs_ct_update_key(key, state, zone, ct); 276 } 277 278 /* This is called to initialize CT key fields possibly coming in from the local 279 * stack. 280 */ 281 void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key) 282 { 283 ovs_ct_update_key(skb, NULL, key, false, false); 284 } 285 286 #define IN6_ADDR_INITIALIZER(ADDR) \ 287 { (ADDR).s6_addr32[0], (ADDR).s6_addr32[1], \ 288 (ADDR).s6_addr32[2], (ADDR).s6_addr32[3] } 289 290 int ovs_ct_put_key(const struct sw_flow_key *swkey, 291 const struct sw_flow_key *output, struct sk_buff *skb) 292 { 293 if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, output->ct_state)) 294 return -EMSGSIZE; 295 296 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 297 nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, output->ct_zone)) 298 return -EMSGSIZE; 299 300 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 301 nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, output->ct.mark)) 302 return -EMSGSIZE; 303 304 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 305 nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(output->ct.labels), 306 &output->ct.labels)) 307 return -EMSGSIZE; 308 309 if (swkey->ct_orig_proto) { 310 if (swkey->eth.type == htons(ETH_P_IP)) { 311 struct ovs_key_ct_tuple_ipv4 orig = { 312 output->ipv4.ct_orig.src, 313 output->ipv4.ct_orig.dst, 314 output->ct.orig_tp.src, 315 output->ct.orig_tp.dst, 316 output->ct_orig_proto, 317 }; 318 if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4, 319 sizeof(orig), &orig)) 320 return -EMSGSIZE; 321 } else if (swkey->eth.type == htons(ETH_P_IPV6)) { 322 struct ovs_key_ct_tuple_ipv6 orig = { 323 IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.src), 324 IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.dst), 325 output->ct.orig_tp.src, 326 output->ct.orig_tp.dst, 327 output->ct_orig_proto, 328 }; 329 if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6, 330 sizeof(orig), &orig)) 331 return -EMSGSIZE; 332 } 333 } 334 335 return 0; 336 } 337 338 static int ovs_ct_set_mark(struct nf_conn *ct, struct sw_flow_key *key, 339 u32 ct_mark, u32 mask) 340 { 341 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) 342 u32 new_mark; 343 344 new_mark = ct_mark | (ct->mark & ~(mask)); 345 if (ct->mark != new_mark) { 346 ct->mark = new_mark; 347 if (nf_ct_is_confirmed(ct)) 348 nf_conntrack_event_cache(IPCT_MARK, ct); 349 key->ct.mark = new_mark; 350 } 351 352 return 0; 353 #else 354 return -ENOTSUPP; 355 #endif 356 } 357 358 static struct nf_conn_labels *ovs_ct_get_conn_labels(struct nf_conn *ct) 359 { 360 struct nf_conn_labels *cl; 361 362 cl = nf_ct_labels_find(ct); 363 if (!cl) { 364 nf_ct_labels_ext_add(ct); 365 cl = nf_ct_labels_find(ct); 366 } 367 368 return cl; 369 } 370 371 /* Initialize labels for a new, yet to be committed conntrack entry. Note that 372 * since the new connection is not yet confirmed, and thus no-one else has 373 * access to it's labels, we simply write them over. 374 */ 375 static int ovs_ct_init_labels(struct nf_conn *ct, struct sw_flow_key *key, 376 const struct ovs_key_ct_labels *labels, 377 const struct ovs_key_ct_labels *mask) 378 { 379 struct nf_conn_labels *cl, *master_cl; 380 bool have_mask = labels_nonzero(mask); 381 382 /* Inherit master's labels to the related connection? */ 383 master_cl = ct->master ? nf_ct_labels_find(ct->master) : NULL; 384 385 if (!master_cl && !have_mask) 386 return 0; /* Nothing to do. */ 387 388 cl = ovs_ct_get_conn_labels(ct); 389 if (!cl) 390 return -ENOSPC; 391 392 /* Inherit the master's labels, if any. */ 393 if (master_cl) 394 *cl = *master_cl; 395 396 if (have_mask) { 397 u32 *dst = (u32 *)cl->bits; 398 int i; 399 400 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) 401 dst[i] = (dst[i] & ~mask->ct_labels_32[i]) | 402 (labels->ct_labels_32[i] 403 & mask->ct_labels_32[i]); 404 } 405 406 /* Labels are included in the IPCTNL_MSG_CT_NEW event only if the 407 * IPCT_LABEL bit is set in the event cache. 408 */ 409 nf_conntrack_event_cache(IPCT_LABEL, ct); 410 411 memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN); 412 413 return 0; 414 } 415 416 static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key, 417 const struct ovs_key_ct_labels *labels, 418 const struct ovs_key_ct_labels *mask) 419 { 420 struct nf_conn_labels *cl; 421 int err; 422 423 cl = ovs_ct_get_conn_labels(ct); 424 if (!cl) 425 return -ENOSPC; 426 427 err = nf_connlabels_replace(ct, labels->ct_labels_32, 428 mask->ct_labels_32, 429 OVS_CT_LABELS_LEN_32); 430 if (err) 431 return err; 432 433 memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN); 434 435 return 0; 436 } 437 438 /* 'skb' should already be pulled to nh_ofs. */ 439 static int ovs_ct_helper(struct sk_buff *skb, u16 proto) 440 { 441 const struct nf_conntrack_helper *helper; 442 const struct nf_conn_help *help; 443 enum ip_conntrack_info ctinfo; 444 unsigned int protoff; 445 struct nf_conn *ct; 446 int err; 447 448 ct = nf_ct_get(skb, &ctinfo); 449 if (!ct || ctinfo == IP_CT_RELATED_REPLY) 450 return NF_ACCEPT; 451 452 help = nfct_help(ct); 453 if (!help) 454 return NF_ACCEPT; 455 456 helper = rcu_dereference(help->helper); 457 if (!helper) 458 return NF_ACCEPT; 459 460 switch (proto) { 461 case NFPROTO_IPV4: 462 protoff = ip_hdrlen(skb); 463 break; 464 case NFPROTO_IPV6: { 465 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 466 __be16 frag_off; 467 int ofs; 468 469 ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr, 470 &frag_off); 471 if (ofs < 0 || (frag_off & htons(~0x7)) != 0) { 472 pr_debug("proto header not found\n"); 473 return NF_ACCEPT; 474 } 475 protoff = ofs; 476 break; 477 } 478 default: 479 WARN_ONCE(1, "helper invoked on non-IP family!"); 480 return NF_DROP; 481 } 482 483 err = helper->help(skb, protoff, ct, ctinfo); 484 if (err != NF_ACCEPT) 485 return err; 486 487 /* Adjust seqs after helper. This is needed due to some helpers (e.g., 488 * FTP with NAT) adusting the TCP payload size when mangling IP 489 * addresses and/or port numbers in the text-based control connection. 490 */ 491 if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && 492 !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) 493 return NF_DROP; 494 return NF_ACCEPT; 495 } 496 497 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero 498 * value if 'skb' is freed. 499 */ 500 static int handle_fragments(struct net *net, struct sw_flow_key *key, 501 u16 zone, struct sk_buff *skb) 502 { 503 struct ovs_skb_cb ovs_cb = *OVS_CB(skb); 504 int err; 505 506 if (key->eth.type == htons(ETH_P_IP)) { 507 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone; 508 509 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); 510 err = ip_defrag(net, skb, user); 511 if (err) 512 return err; 513 514 ovs_cb.mru = IPCB(skb)->frag_max_size; 515 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) 516 } else if (key->eth.type == htons(ETH_P_IPV6)) { 517 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone; 518 519 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); 520 err = nf_ct_frag6_gather(net, skb, user); 521 if (err) { 522 if (err != -EINPROGRESS) 523 kfree_skb(skb); 524 return err; 525 } 526 527 key->ip.proto = ipv6_hdr(skb)->nexthdr; 528 ovs_cb.mru = IP6CB(skb)->frag_max_size; 529 #endif 530 } else { 531 kfree_skb(skb); 532 return -EPFNOSUPPORT; 533 } 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 } 542 543 static struct nf_conntrack_expect * 544 ovs_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. */ 583 static enum ip_conntrack_info 584 ovs_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 */ 607 static struct nf_conn * 608 ovs_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 } 649 650 static 651 struct 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. */ 679 static 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 /* Force conntrack entry direction to the current packet? */ 709 if (info->force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) { 710 /* Delete the conntrack entry if confirmed, else just release 711 * the reference. 712 */ 713 if (nf_ct_is_confirmed(ct)) 714 nf_ct_delete(ct, 0, 0); 715 716 nf_conntrack_put(&ct->ct_general); 717 nf_ct_set(skb, NULL, 0); 718 return false; 719 } 720 721 return ct_executed; 722 } 723 724 #if IS_ENABLED(CONFIG_NF_NAT) 725 /* Modelled after nf_nat_ipv[46]_fn(). 726 * range is only used for new, uninitialized NAT state. 727 * Returns either NF_ACCEPT or NF_DROP. 728 */ 729 static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct, 730 enum ip_conntrack_info ctinfo, 731 const struct nf_nat_range2 *range, 732 enum nf_nat_manip_type maniptype) 733 { 734 int hooknum, nh_off, err = NF_ACCEPT; 735 736 nh_off = skb_network_offset(skb); 737 skb_pull_rcsum(skb, nh_off); 738 739 /* See HOOK2MANIP(). */ 740 if (maniptype == NF_NAT_MANIP_SRC) 741 hooknum = NF_INET_LOCAL_IN; /* Source NAT */ 742 else 743 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */ 744 745 switch (ctinfo) { 746 case IP_CT_RELATED: 747 case IP_CT_RELATED_REPLY: 748 if (IS_ENABLED(CONFIG_NF_NAT) && 749 skb->protocol == htons(ETH_P_IP) && 750 ip_hdr(skb)->protocol == IPPROTO_ICMP) { 751 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo, 752 hooknum)) 753 err = NF_DROP; 754 goto push; 755 } else if (IS_ENABLED(CONFIG_IPV6) && 756 skb->protocol == htons(ETH_P_IPV6)) { 757 __be16 frag_off; 758 u8 nexthdr = ipv6_hdr(skb)->nexthdr; 759 int hdrlen = ipv6_skip_exthdr(skb, 760 sizeof(struct ipv6hdr), 761 &nexthdr, &frag_off); 762 763 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) { 764 if (!nf_nat_icmpv6_reply_translation(skb, ct, 765 ctinfo, 766 hooknum, 767 hdrlen)) 768 err = NF_DROP; 769 goto push; 770 } 771 } 772 /* Non-ICMP, fall thru to initialize if needed. */ 773 /* fall through */ 774 case IP_CT_NEW: 775 /* Seen it before? This can happen for loopback, retrans, 776 * or local packets. 777 */ 778 if (!nf_nat_initialized(ct, maniptype)) { 779 /* Initialize according to the NAT action. */ 780 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS) 781 /* Action is set up to establish a new 782 * mapping. 783 */ 784 ? nf_nat_setup_info(ct, range, maniptype) 785 : nf_nat_alloc_null_binding(ct, hooknum); 786 if (err != NF_ACCEPT) 787 goto push; 788 } 789 break; 790 791 case IP_CT_ESTABLISHED: 792 case IP_CT_ESTABLISHED_REPLY: 793 break; 794 795 default: 796 err = NF_DROP; 797 goto push; 798 } 799 800 err = nf_nat_packet(ct, ctinfo, hooknum, skb); 801 push: 802 skb_push(skb, nh_off); 803 skb_postpush_rcsum(skb, skb->data, nh_off); 804 805 return err; 806 } 807 808 static void ovs_nat_update_key(struct sw_flow_key *key, 809 const struct sk_buff *skb, 810 enum nf_nat_manip_type maniptype) 811 { 812 if (maniptype == NF_NAT_MANIP_SRC) { 813 __be16 src; 814 815 key->ct_state |= OVS_CS_F_SRC_NAT; 816 if (key->eth.type == htons(ETH_P_IP)) 817 key->ipv4.addr.src = ip_hdr(skb)->saddr; 818 else if (key->eth.type == htons(ETH_P_IPV6)) 819 memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr, 820 sizeof(key->ipv6.addr.src)); 821 else 822 return; 823 824 if (key->ip.proto == IPPROTO_UDP) 825 src = udp_hdr(skb)->source; 826 else if (key->ip.proto == IPPROTO_TCP) 827 src = tcp_hdr(skb)->source; 828 else if (key->ip.proto == IPPROTO_SCTP) 829 src = sctp_hdr(skb)->source; 830 else 831 return; 832 833 key->tp.src = src; 834 } else { 835 __be16 dst; 836 837 key->ct_state |= OVS_CS_F_DST_NAT; 838 if (key->eth.type == htons(ETH_P_IP)) 839 key->ipv4.addr.dst = ip_hdr(skb)->daddr; 840 else if (key->eth.type == htons(ETH_P_IPV6)) 841 memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr, 842 sizeof(key->ipv6.addr.dst)); 843 else 844 return; 845 846 if (key->ip.proto == IPPROTO_UDP) 847 dst = udp_hdr(skb)->dest; 848 else if (key->ip.proto == IPPROTO_TCP) 849 dst = tcp_hdr(skb)->dest; 850 else if (key->ip.proto == IPPROTO_SCTP) 851 dst = sctp_hdr(skb)->dest; 852 else 853 return; 854 855 key->tp.dst = dst; 856 } 857 } 858 859 /* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */ 860 static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, 861 const struct ovs_conntrack_info *info, 862 struct sk_buff *skb, struct nf_conn *ct, 863 enum ip_conntrack_info ctinfo) 864 { 865 enum nf_nat_manip_type maniptype; 866 int err; 867 868 /* Add NAT extension if not confirmed yet. */ 869 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct)) 870 return NF_ACCEPT; /* Can't NAT. */ 871 872 /* Determine NAT type. 873 * Check if the NAT type can be deduced from the tracked connection. 874 * Make sure new expected connections (IP_CT_RELATED) are NATted only 875 * when committing. 876 */ 877 if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW && 878 ct->status & IPS_NAT_MASK && 879 (ctinfo != IP_CT_RELATED || info->commit)) { 880 /* NAT an established or related connection like before. */ 881 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) 882 /* This is the REPLY direction for a connection 883 * for which NAT was applied in the forward 884 * direction. Do the reverse NAT. 885 */ 886 maniptype = ct->status & IPS_SRC_NAT 887 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC; 888 else 889 maniptype = ct->status & IPS_SRC_NAT 890 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST; 891 } else if (info->nat & OVS_CT_SRC_NAT) { 892 maniptype = NF_NAT_MANIP_SRC; 893 } else if (info->nat & OVS_CT_DST_NAT) { 894 maniptype = NF_NAT_MANIP_DST; 895 } else { 896 return NF_ACCEPT; /* Connection is not NATed. */ 897 } 898 err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype); 899 900 /* Mark NAT done if successful and update the flow key. */ 901 if (err == NF_ACCEPT) 902 ovs_nat_update_key(key, skb, maniptype); 903 904 return err; 905 } 906 #else /* !CONFIG_NF_NAT */ 907 static int ovs_ct_nat(struct net *net, struct sw_flow_key *key, 908 const struct ovs_conntrack_info *info, 909 struct sk_buff *skb, struct nf_conn *ct, 910 enum ip_conntrack_info ctinfo) 911 { 912 return NF_ACCEPT; 913 } 914 #endif 915 916 /* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if 917 * not done already. Update key with new CT state after passing the packet 918 * through conntrack. 919 * Note that if the packet is deemed invalid by conntrack, skb->_nfct will be 920 * set to NULL and 0 will be returned. 921 */ 922 static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key, 923 const struct ovs_conntrack_info *info, 924 struct sk_buff *skb) 925 { 926 /* If we are recirculating packets to match on conntrack fields and 927 * committing with a separate conntrack action, then we don't need to 928 * actually run the packet through conntrack twice unless it's for a 929 * different zone. 930 */ 931 bool cached = skb_nfct_cached(net, key, info, skb); 932 enum ip_conntrack_info ctinfo; 933 struct nf_conn *ct; 934 935 if (!cached) { 936 struct nf_hook_state state = { 937 .hook = NF_INET_PRE_ROUTING, 938 .pf = info->family, 939 .net = net, 940 }; 941 struct nf_conn *tmpl = info->ct; 942 int err; 943 944 /* Associate skb with specified zone. */ 945 if (tmpl) { 946 if (skb_nfct(skb)) 947 nf_conntrack_put(skb_nfct(skb)); 948 nf_conntrack_get(&tmpl->ct_general); 949 nf_ct_set(skb, tmpl, IP_CT_NEW); 950 } 951 952 err = nf_conntrack_in(skb, &state); 953 if (err != NF_ACCEPT) 954 return -ENOENT; 955 956 /* Clear CT state NAT flags to mark that we have not yet done 957 * NAT after the nf_conntrack_in() call. We can actually clear 958 * the whole state, as it will be re-initialized below. 959 */ 960 key->ct_state = 0; 961 962 /* Update the key, but keep the NAT flags. */ 963 ovs_ct_update_key(skb, info, key, true, true); 964 } 965 966 ct = nf_ct_get(skb, &ctinfo); 967 if (ct) { 968 /* Packets starting a new connection must be NATted before the 969 * helper, so that the helper knows about the NAT. We enforce 970 * this by delaying both NAT and helper calls for unconfirmed 971 * connections until the committing CT action. For later 972 * packets NAT and Helper may be called in either order. 973 * 974 * NAT will be done only if the CT action has NAT, and only 975 * once per packet (per zone), as guarded by the NAT bits in 976 * the key->ct_state. 977 */ 978 if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) && 979 (nf_ct_is_confirmed(ct) || info->commit) && 980 ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) { 981 return -EINVAL; 982 } 983 984 /* Userspace may decide to perform a ct lookup without a helper 985 * specified followed by a (recirculate and) commit with one. 986 * Therefore, for unconfirmed connections which we will commit, 987 * we need to attach the helper here. 988 */ 989 if (!nf_ct_is_confirmed(ct) && info->commit && 990 info->helper && !nfct_help(ct)) { 991 int err = __nf_ct_try_assign_helper(ct, info->ct, 992 GFP_ATOMIC); 993 if (err) 994 return err; 995 996 /* helper installed, add seqadj if NAT is required */ 997 if (info->nat && !nfct_seqadj(ct)) { 998 if (!nfct_seqadj_ext_add(ct)) 999 return -EINVAL; 1000 } 1001 } 1002 1003 /* Call the helper only if: 1004 * - nf_conntrack_in() was executed above ("!cached") for a 1005 * confirmed connection, or 1006 * - When committing an unconfirmed connection. 1007 */ 1008 if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) && 1009 ovs_ct_helper(skb, info->family) != NF_ACCEPT) { 1010 return -EINVAL; 1011 } 1012 } 1013 1014 return 0; 1015 } 1016 1017 /* Lookup connection and read fields into key. */ 1018 static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key, 1019 const struct ovs_conntrack_info *info, 1020 struct sk_buff *skb) 1021 { 1022 struct nf_conntrack_expect *exp; 1023 1024 /* If we pass an expected packet through nf_conntrack_in() the 1025 * expectation is typically removed, but the packet could still be 1026 * lost in upcall processing. To prevent this from happening we 1027 * perform an explicit expectation lookup. Expected connections are 1028 * always new, and will be passed through conntrack only when they are 1029 * committed, as it is OK to remove the expectation at that time. 1030 */ 1031 exp = ovs_ct_expect_find(net, &info->zone, info->family, skb); 1032 if (exp) { 1033 u8 state; 1034 1035 /* NOTE: New connections are NATted and Helped only when 1036 * committed, so we are not calling into NAT here. 1037 */ 1038 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED; 1039 __ovs_ct_update_key(key, state, &info->zone, exp->master); 1040 } else { 1041 struct nf_conn *ct; 1042 int err; 1043 1044 err = __ovs_ct_lookup(net, key, info, skb); 1045 if (err) 1046 return err; 1047 1048 ct = (struct nf_conn *)skb_nfct(skb); 1049 if (ct) 1050 nf_ct_deliver_cached_events(ct); 1051 } 1052 1053 return 0; 1054 } 1055 1056 static bool labels_nonzero(const struct ovs_key_ct_labels *labels) 1057 { 1058 size_t i; 1059 1060 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) 1061 if (labels->ct_labels_32[i]) 1062 return true; 1063 1064 return false; 1065 } 1066 1067 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1068 static struct hlist_head *ct_limit_hash_bucket( 1069 const struct ovs_ct_limit_info *info, u16 zone) 1070 { 1071 return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)]; 1072 } 1073 1074 /* Call with ovs_mutex */ 1075 static void ct_limit_set(const struct ovs_ct_limit_info *info, 1076 struct ovs_ct_limit *new_ct_limit) 1077 { 1078 struct ovs_ct_limit *ct_limit; 1079 struct hlist_head *head; 1080 1081 head = ct_limit_hash_bucket(info, new_ct_limit->zone); 1082 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1083 if (ct_limit->zone == new_ct_limit->zone) { 1084 hlist_replace_rcu(&ct_limit->hlist_node, 1085 &new_ct_limit->hlist_node); 1086 kfree_rcu(ct_limit, rcu); 1087 return; 1088 } 1089 } 1090 1091 hlist_add_head_rcu(&new_ct_limit->hlist_node, head); 1092 } 1093 1094 /* Call with ovs_mutex */ 1095 static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone) 1096 { 1097 struct ovs_ct_limit *ct_limit; 1098 struct hlist_head *head; 1099 struct hlist_node *n; 1100 1101 head = ct_limit_hash_bucket(info, zone); 1102 hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) { 1103 if (ct_limit->zone == zone) { 1104 hlist_del_rcu(&ct_limit->hlist_node); 1105 kfree_rcu(ct_limit, rcu); 1106 return; 1107 } 1108 } 1109 } 1110 1111 /* Call with RCU read lock */ 1112 static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone) 1113 { 1114 struct ovs_ct_limit *ct_limit; 1115 struct hlist_head *head; 1116 1117 head = ct_limit_hash_bucket(info, zone); 1118 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1119 if (ct_limit->zone == zone) 1120 return ct_limit->limit; 1121 } 1122 1123 return info->default_limit; 1124 } 1125 1126 static int ovs_ct_check_limit(struct net *net, 1127 const struct ovs_conntrack_info *info, 1128 const struct nf_conntrack_tuple *tuple) 1129 { 1130 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1131 const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 1132 u32 per_zone_limit, connections; 1133 u32 conncount_key; 1134 1135 conncount_key = info->zone.id; 1136 1137 per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id); 1138 if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED) 1139 return 0; 1140 1141 connections = nf_conncount_count(net, ct_limit_info->data, 1142 &conncount_key, tuple, &info->zone); 1143 if (connections > per_zone_limit) 1144 return -ENOMEM; 1145 1146 return 0; 1147 } 1148 #endif 1149 1150 /* Lookup connection and confirm if unconfirmed. */ 1151 static int ovs_ct_commit(struct net *net, struct sw_flow_key *key, 1152 const struct ovs_conntrack_info *info, 1153 struct sk_buff *skb) 1154 { 1155 enum ip_conntrack_info ctinfo; 1156 struct nf_conn *ct; 1157 int err; 1158 1159 err = __ovs_ct_lookup(net, key, info, skb); 1160 if (err) 1161 return err; 1162 1163 /* The connection could be invalid, in which case this is a no-op.*/ 1164 ct = nf_ct_get(skb, &ctinfo); 1165 if (!ct) 1166 return 0; 1167 1168 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1169 if (static_branch_unlikely(&ovs_ct_limit_enabled)) { 1170 if (!nf_ct_is_confirmed(ct)) { 1171 err = ovs_ct_check_limit(net, info, 1172 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); 1173 if (err) { 1174 net_warn_ratelimited("openvswitch: zone: %u " 1175 "exceeds conntrack limit\n", 1176 info->zone.id); 1177 return err; 1178 } 1179 } 1180 } 1181 #endif 1182 1183 /* Set the conntrack event mask if given. NEW and DELETE events have 1184 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener 1185 * typically would receive many kinds of updates. Setting the event 1186 * mask allows those events to be filtered. The set event mask will 1187 * remain in effect for the lifetime of the connection unless changed 1188 * by a further CT action with both the commit flag and the eventmask 1189 * option. */ 1190 if (info->have_eventmask) { 1191 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct); 1192 1193 if (cache) 1194 cache->ctmask = info->eventmask; 1195 } 1196 1197 /* Apply changes before confirming the connection so that the initial 1198 * conntrack NEW netlink event carries the values given in the CT 1199 * action. 1200 */ 1201 if (info->mark.mask) { 1202 err = ovs_ct_set_mark(ct, key, info->mark.value, 1203 info->mark.mask); 1204 if (err) 1205 return err; 1206 } 1207 if (!nf_ct_is_confirmed(ct)) { 1208 err = ovs_ct_init_labels(ct, key, &info->labels.value, 1209 &info->labels.mask); 1210 if (err) 1211 return err; 1212 } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1213 labels_nonzero(&info->labels.mask)) { 1214 err = ovs_ct_set_labels(ct, key, &info->labels.value, 1215 &info->labels.mask); 1216 if (err) 1217 return err; 1218 } 1219 /* This will take care of sending queued events even if the connection 1220 * is already confirmed. 1221 */ 1222 if (nf_conntrack_confirm(skb) != NF_ACCEPT) 1223 return -EINVAL; 1224 1225 return 0; 1226 } 1227 1228 /* Trim the skb to the length specified by the IP/IPv6 header, 1229 * removing any trailing lower-layer padding. This prepares the skb 1230 * for higher-layer processing that assumes skb->len excludes padding 1231 * (such as nf_ip_checksum). The caller needs to pull the skb to the 1232 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 1233 */ 1234 static int ovs_skb_network_trim(struct sk_buff *skb) 1235 { 1236 unsigned int len; 1237 int err; 1238 1239 switch (skb->protocol) { 1240 case htons(ETH_P_IP): 1241 len = ntohs(ip_hdr(skb)->tot_len); 1242 break; 1243 case htons(ETH_P_IPV6): 1244 len = sizeof(struct ipv6hdr) 1245 + ntohs(ipv6_hdr(skb)->payload_len); 1246 break; 1247 default: 1248 len = skb->len; 1249 } 1250 1251 err = pskb_trim_rcsum(skb, len); 1252 if (err) 1253 kfree_skb(skb); 1254 1255 return err; 1256 } 1257 1258 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero 1259 * value if 'skb' is freed. 1260 */ 1261 int ovs_ct_execute(struct net *net, struct sk_buff *skb, 1262 struct sw_flow_key *key, 1263 const struct ovs_conntrack_info *info) 1264 { 1265 int nh_ofs; 1266 int err; 1267 1268 /* The conntrack module expects to be working at L3. */ 1269 nh_ofs = skb_network_offset(skb); 1270 skb_pull_rcsum(skb, nh_ofs); 1271 1272 err = ovs_skb_network_trim(skb); 1273 if (err) 1274 return err; 1275 1276 if (key->ip.frag != OVS_FRAG_TYPE_NONE) { 1277 err = handle_fragments(net, key, info->zone.id, skb); 1278 if (err) 1279 return err; 1280 } 1281 1282 if (info->commit) 1283 err = ovs_ct_commit(net, key, info, skb); 1284 else 1285 err = ovs_ct_lookup(net, key, info, skb); 1286 1287 skb_push(skb, nh_ofs); 1288 skb_postpush_rcsum(skb, skb->data, nh_ofs); 1289 if (err) 1290 kfree_skb(skb); 1291 return err; 1292 } 1293 1294 int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key) 1295 { 1296 if (skb_nfct(skb)) { 1297 nf_conntrack_put(skb_nfct(skb)); 1298 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 1299 ovs_ct_fill_key(skb, key); 1300 } 1301 1302 return 0; 1303 } 1304 1305 static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name, 1306 const struct sw_flow_key *key, bool log) 1307 { 1308 struct nf_conntrack_helper *helper; 1309 struct nf_conn_help *help; 1310 int ret = 0; 1311 1312 helper = nf_conntrack_helper_try_module_get(name, info->family, 1313 key->ip.proto); 1314 if (!helper) { 1315 OVS_NLERR(log, "Unknown helper \"%s\"", name); 1316 return -EINVAL; 1317 } 1318 1319 help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL); 1320 if (!help) { 1321 nf_conntrack_helper_put(helper); 1322 return -ENOMEM; 1323 } 1324 1325 #if IS_ENABLED(CONFIG_NF_NAT) 1326 if (info->nat) { 1327 ret = nf_nat_helper_try_module_get(name, info->family, 1328 key->ip.proto); 1329 if (ret) { 1330 nf_conntrack_helper_put(helper); 1331 OVS_NLERR(log, "Failed to load \"%s\" NAT helper, error: %d", 1332 name, ret); 1333 return ret; 1334 } 1335 } 1336 #endif 1337 rcu_assign_pointer(help->helper, helper); 1338 info->helper = helper; 1339 return ret; 1340 } 1341 1342 #if IS_ENABLED(CONFIG_NF_NAT) 1343 static int parse_nat(const struct nlattr *attr, 1344 struct ovs_conntrack_info *info, bool log) 1345 { 1346 struct nlattr *a; 1347 int rem; 1348 bool have_ip_max = false; 1349 bool have_proto_max = false; 1350 bool ip_vers = (info->family == NFPROTO_IPV6); 1351 1352 nla_for_each_nested(a, attr, rem) { 1353 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = { 1354 [OVS_NAT_ATTR_SRC] = {0, 0}, 1355 [OVS_NAT_ATTR_DST] = {0, 0}, 1356 [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr), 1357 sizeof(struct in6_addr)}, 1358 [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr), 1359 sizeof(struct in6_addr)}, 1360 [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)}, 1361 [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)}, 1362 [OVS_NAT_ATTR_PERSISTENT] = {0, 0}, 1363 [OVS_NAT_ATTR_PROTO_HASH] = {0, 0}, 1364 [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0}, 1365 }; 1366 int type = nla_type(a); 1367 1368 if (type > OVS_NAT_ATTR_MAX) { 1369 OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)", 1370 type, OVS_NAT_ATTR_MAX); 1371 return -EINVAL; 1372 } 1373 1374 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) { 1375 OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)", 1376 type, nla_len(a), 1377 ovs_nat_attr_lens[type][ip_vers]); 1378 return -EINVAL; 1379 } 1380 1381 switch (type) { 1382 case OVS_NAT_ATTR_SRC: 1383 case OVS_NAT_ATTR_DST: 1384 if (info->nat) { 1385 OVS_NLERR(log, "Only one type of NAT may be specified"); 1386 return -ERANGE; 1387 } 1388 info->nat |= OVS_CT_NAT; 1389 info->nat |= ((type == OVS_NAT_ATTR_SRC) 1390 ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT); 1391 break; 1392 1393 case OVS_NAT_ATTR_IP_MIN: 1394 nla_memcpy(&info->range.min_addr, a, 1395 sizeof(info->range.min_addr)); 1396 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1397 break; 1398 1399 case OVS_NAT_ATTR_IP_MAX: 1400 have_ip_max = true; 1401 nla_memcpy(&info->range.max_addr, a, 1402 sizeof(info->range.max_addr)); 1403 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1404 break; 1405 1406 case OVS_NAT_ATTR_PROTO_MIN: 1407 info->range.min_proto.all = htons(nla_get_u16(a)); 1408 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1409 break; 1410 1411 case OVS_NAT_ATTR_PROTO_MAX: 1412 have_proto_max = true; 1413 info->range.max_proto.all = htons(nla_get_u16(a)); 1414 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1415 break; 1416 1417 case OVS_NAT_ATTR_PERSISTENT: 1418 info->range.flags |= NF_NAT_RANGE_PERSISTENT; 1419 break; 1420 1421 case OVS_NAT_ATTR_PROTO_HASH: 1422 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM; 1423 break; 1424 1425 case OVS_NAT_ATTR_PROTO_RANDOM: 1426 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY; 1427 break; 1428 1429 default: 1430 OVS_NLERR(log, "Unknown nat attribute (%d)", type); 1431 return -EINVAL; 1432 } 1433 } 1434 1435 if (rem > 0) { 1436 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem); 1437 return -EINVAL; 1438 } 1439 if (!info->nat) { 1440 /* Do not allow flags if no type is given. */ 1441 if (info->range.flags) { 1442 OVS_NLERR(log, 1443 "NAT flags may be given only when NAT range (SRC or DST) is also specified." 1444 ); 1445 return -EINVAL; 1446 } 1447 info->nat = OVS_CT_NAT; /* NAT existing connections. */ 1448 } else if (!info->commit) { 1449 OVS_NLERR(log, 1450 "NAT attributes may be specified only when CT COMMIT flag is also specified." 1451 ); 1452 return -EINVAL; 1453 } 1454 /* Allow missing IP_MAX. */ 1455 if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) { 1456 memcpy(&info->range.max_addr, &info->range.min_addr, 1457 sizeof(info->range.max_addr)); 1458 } 1459 /* Allow missing PROTO_MAX. */ 1460 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1461 !have_proto_max) { 1462 info->range.max_proto.all = info->range.min_proto.all; 1463 } 1464 return 0; 1465 } 1466 #endif 1467 1468 static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = { 1469 [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1470 [OVS_CT_ATTR_FORCE_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1471 [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16), 1472 .maxlen = sizeof(u16) }, 1473 [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark), 1474 .maxlen = sizeof(struct md_mark) }, 1475 [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels), 1476 .maxlen = sizeof(struct md_labels) }, 1477 [OVS_CT_ATTR_HELPER] = { .minlen = 1, 1478 .maxlen = NF_CT_HELPER_NAME_LEN }, 1479 #if IS_ENABLED(CONFIG_NF_NAT) 1480 /* NAT length is checked when parsing the nested attributes. */ 1481 [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX }, 1482 #endif 1483 [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32), 1484 .maxlen = sizeof(u32) }, 1485 [OVS_CT_ATTR_TIMEOUT] = { .minlen = 1, 1486 .maxlen = CTNL_TIMEOUT_NAME_MAX }, 1487 }; 1488 1489 static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info, 1490 const char **helper, bool log) 1491 { 1492 struct nlattr *a; 1493 int rem; 1494 1495 nla_for_each_nested(a, attr, rem) { 1496 int type = nla_type(a); 1497 int maxlen; 1498 int minlen; 1499 1500 if (type > OVS_CT_ATTR_MAX) { 1501 OVS_NLERR(log, 1502 "Unknown conntrack attr (type=%d, max=%d)", 1503 type, OVS_CT_ATTR_MAX); 1504 return -EINVAL; 1505 } 1506 1507 maxlen = ovs_ct_attr_lens[type].maxlen; 1508 minlen = ovs_ct_attr_lens[type].minlen; 1509 if (nla_len(a) < minlen || nla_len(a) > maxlen) { 1510 OVS_NLERR(log, 1511 "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)", 1512 type, nla_len(a), maxlen); 1513 return -EINVAL; 1514 } 1515 1516 switch (type) { 1517 case OVS_CT_ATTR_FORCE_COMMIT: 1518 info->force = true; 1519 /* fall through. */ 1520 case OVS_CT_ATTR_COMMIT: 1521 info->commit = true; 1522 break; 1523 #ifdef CONFIG_NF_CONNTRACK_ZONES 1524 case OVS_CT_ATTR_ZONE: 1525 info->zone.id = nla_get_u16(a); 1526 break; 1527 #endif 1528 #ifdef CONFIG_NF_CONNTRACK_MARK 1529 case OVS_CT_ATTR_MARK: { 1530 struct md_mark *mark = nla_data(a); 1531 1532 if (!mark->mask) { 1533 OVS_NLERR(log, "ct_mark mask cannot be 0"); 1534 return -EINVAL; 1535 } 1536 info->mark = *mark; 1537 break; 1538 } 1539 #endif 1540 #ifdef CONFIG_NF_CONNTRACK_LABELS 1541 case OVS_CT_ATTR_LABELS: { 1542 struct md_labels *labels = nla_data(a); 1543 1544 if (!labels_nonzero(&labels->mask)) { 1545 OVS_NLERR(log, "ct_labels mask cannot be 0"); 1546 return -EINVAL; 1547 } 1548 info->labels = *labels; 1549 break; 1550 } 1551 #endif 1552 case OVS_CT_ATTR_HELPER: 1553 *helper = nla_data(a); 1554 if (!memchr(*helper, '\0', nla_len(a))) { 1555 OVS_NLERR(log, "Invalid conntrack helper"); 1556 return -EINVAL; 1557 } 1558 break; 1559 #if IS_ENABLED(CONFIG_NF_NAT) 1560 case OVS_CT_ATTR_NAT: { 1561 int err = parse_nat(a, info, log); 1562 1563 if (err) 1564 return err; 1565 break; 1566 } 1567 #endif 1568 case OVS_CT_ATTR_EVENTMASK: 1569 info->have_eventmask = true; 1570 info->eventmask = nla_get_u32(a); 1571 break; 1572 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT 1573 case OVS_CT_ATTR_TIMEOUT: 1574 memcpy(info->timeout, nla_data(a), nla_len(a)); 1575 if (!memchr(info->timeout, '\0', nla_len(a))) { 1576 OVS_NLERR(log, "Invalid conntrack helper"); 1577 return -EINVAL; 1578 } 1579 break; 1580 #endif 1581 1582 default: 1583 OVS_NLERR(log, "Unknown conntrack attr (%d)", 1584 type); 1585 return -EINVAL; 1586 } 1587 } 1588 1589 #ifdef CONFIG_NF_CONNTRACK_MARK 1590 if (!info->commit && info->mark.mask) { 1591 OVS_NLERR(log, 1592 "Setting conntrack mark requires 'commit' flag."); 1593 return -EINVAL; 1594 } 1595 #endif 1596 #ifdef CONFIG_NF_CONNTRACK_LABELS 1597 if (!info->commit && labels_nonzero(&info->labels.mask)) { 1598 OVS_NLERR(log, 1599 "Setting conntrack labels requires 'commit' flag."); 1600 return -EINVAL; 1601 } 1602 #endif 1603 if (rem > 0) { 1604 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem); 1605 return -EINVAL; 1606 } 1607 1608 return 0; 1609 } 1610 1611 bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr) 1612 { 1613 if (attr == OVS_KEY_ATTR_CT_STATE) 1614 return true; 1615 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1616 attr == OVS_KEY_ATTR_CT_ZONE) 1617 return true; 1618 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1619 attr == OVS_KEY_ATTR_CT_MARK) 1620 return true; 1621 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1622 attr == OVS_KEY_ATTR_CT_LABELS) { 1623 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1624 1625 return ovs_net->xt_label; 1626 } 1627 1628 return false; 1629 } 1630 1631 int ovs_ct_copy_action(struct net *net, const struct nlattr *attr, 1632 const struct sw_flow_key *key, 1633 struct sw_flow_actions **sfa, bool log) 1634 { 1635 struct ovs_conntrack_info ct_info; 1636 const char *helper = NULL; 1637 u16 family; 1638 int err; 1639 1640 family = key_to_nfproto(key); 1641 if (family == NFPROTO_UNSPEC) { 1642 OVS_NLERR(log, "ct family unspecified"); 1643 return -EINVAL; 1644 } 1645 1646 memset(&ct_info, 0, sizeof(ct_info)); 1647 ct_info.family = family; 1648 1649 nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID, 1650 NF_CT_DEFAULT_ZONE_DIR, 0); 1651 1652 err = parse_ct(attr, &ct_info, &helper, log); 1653 if (err) 1654 return err; 1655 1656 /* Set up template for tracking connections in specific zones. */ 1657 ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL); 1658 if (!ct_info.ct) { 1659 OVS_NLERR(log, "Failed to allocate conntrack template"); 1660 return -ENOMEM; 1661 } 1662 1663 if (ct_info.timeout[0]) { 1664 if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto, 1665 ct_info.timeout)) 1666 pr_info_ratelimited("Failed to associated timeout " 1667 "policy `%s'\n", ct_info.timeout); 1668 } 1669 1670 if (helper) { 1671 err = ovs_ct_add_helper(&ct_info, helper, key, log); 1672 if (err) 1673 goto err_free_ct; 1674 } 1675 1676 err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info, 1677 sizeof(ct_info), log); 1678 if (err) 1679 goto err_free_ct; 1680 1681 __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status); 1682 nf_conntrack_get(&ct_info.ct->ct_general); 1683 return 0; 1684 err_free_ct: 1685 __ovs_ct_free_action(&ct_info); 1686 return err; 1687 } 1688 1689 #if IS_ENABLED(CONFIG_NF_NAT) 1690 static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, 1691 struct sk_buff *skb) 1692 { 1693 struct nlattr *start; 1694 1695 start = nla_nest_start_noflag(skb, OVS_CT_ATTR_NAT); 1696 if (!start) 1697 return false; 1698 1699 if (info->nat & OVS_CT_SRC_NAT) { 1700 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC)) 1701 return false; 1702 } else if (info->nat & OVS_CT_DST_NAT) { 1703 if (nla_put_flag(skb, OVS_NAT_ATTR_DST)) 1704 return false; 1705 } else { 1706 goto out; 1707 } 1708 1709 if (info->range.flags & NF_NAT_RANGE_MAP_IPS) { 1710 if (IS_ENABLED(CONFIG_NF_NAT) && 1711 info->family == NFPROTO_IPV4) { 1712 if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN, 1713 info->range.min_addr.ip) || 1714 (info->range.max_addr.ip 1715 != info->range.min_addr.ip && 1716 (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX, 1717 info->range.max_addr.ip)))) 1718 return false; 1719 } else if (IS_ENABLED(CONFIG_IPV6) && 1720 info->family == NFPROTO_IPV6) { 1721 if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN, 1722 &info->range.min_addr.in6) || 1723 (memcmp(&info->range.max_addr.in6, 1724 &info->range.min_addr.in6, 1725 sizeof(info->range.max_addr.in6)) && 1726 (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX, 1727 &info->range.max_addr.in6)))) 1728 return false; 1729 } else { 1730 return false; 1731 } 1732 } 1733 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1734 (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN, 1735 ntohs(info->range.min_proto.all)) || 1736 (info->range.max_proto.all != info->range.min_proto.all && 1737 nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX, 1738 ntohs(info->range.max_proto.all))))) 1739 return false; 1740 1741 if (info->range.flags & NF_NAT_RANGE_PERSISTENT && 1742 nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT)) 1743 return false; 1744 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM && 1745 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH)) 1746 return false; 1747 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY && 1748 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM)) 1749 return false; 1750 out: 1751 nla_nest_end(skb, start); 1752 1753 return true; 1754 } 1755 #endif 1756 1757 int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info, 1758 struct sk_buff *skb) 1759 { 1760 struct nlattr *start; 1761 1762 start = nla_nest_start_noflag(skb, OVS_ACTION_ATTR_CT); 1763 if (!start) 1764 return -EMSGSIZE; 1765 1766 if (ct_info->commit && nla_put_flag(skb, ct_info->force 1767 ? OVS_CT_ATTR_FORCE_COMMIT 1768 : OVS_CT_ATTR_COMMIT)) 1769 return -EMSGSIZE; 1770 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1771 nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id)) 1772 return -EMSGSIZE; 1773 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask && 1774 nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark), 1775 &ct_info->mark)) 1776 return -EMSGSIZE; 1777 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1778 labels_nonzero(&ct_info->labels.mask) && 1779 nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels), 1780 &ct_info->labels)) 1781 return -EMSGSIZE; 1782 if (ct_info->helper) { 1783 if (nla_put_string(skb, OVS_CT_ATTR_HELPER, 1784 ct_info->helper->name)) 1785 return -EMSGSIZE; 1786 } 1787 if (ct_info->have_eventmask && 1788 nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask)) 1789 return -EMSGSIZE; 1790 if (ct_info->timeout[0]) { 1791 if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout)) 1792 return -EMSGSIZE; 1793 } 1794 1795 #if IS_ENABLED(CONFIG_NF_NAT) 1796 if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb)) 1797 return -EMSGSIZE; 1798 #endif 1799 nla_nest_end(skb, start); 1800 1801 return 0; 1802 } 1803 1804 void ovs_ct_free_action(const struct nlattr *a) 1805 { 1806 struct ovs_conntrack_info *ct_info = nla_data(a); 1807 1808 __ovs_ct_free_action(ct_info); 1809 } 1810 1811 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info) 1812 { 1813 if (ct_info->helper) { 1814 #if IS_ENABLED(CONFIG_NF_NAT) 1815 if (ct_info->nat) 1816 nf_nat_helper_put(ct_info->helper); 1817 #endif 1818 nf_conntrack_helper_put(ct_info->helper); 1819 } 1820 if (ct_info->ct) { 1821 if (ct_info->timeout[0]) 1822 nf_ct_destroy_timeout(ct_info->ct); 1823 nf_ct_tmpl_free(ct_info->ct); 1824 } 1825 } 1826 1827 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1828 static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net) 1829 { 1830 int i, err; 1831 1832 ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info), 1833 GFP_KERNEL); 1834 if (!ovs_net->ct_limit_info) 1835 return -ENOMEM; 1836 1837 ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT; 1838 ovs_net->ct_limit_info->limits = 1839 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head), 1840 GFP_KERNEL); 1841 if (!ovs_net->ct_limit_info->limits) { 1842 kfree(ovs_net->ct_limit_info); 1843 return -ENOMEM; 1844 } 1845 1846 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++) 1847 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]); 1848 1849 ovs_net->ct_limit_info->data = 1850 nf_conncount_init(net, NFPROTO_INET, sizeof(u32)); 1851 1852 if (IS_ERR(ovs_net->ct_limit_info->data)) { 1853 err = PTR_ERR(ovs_net->ct_limit_info->data); 1854 kfree(ovs_net->ct_limit_info->limits); 1855 kfree(ovs_net->ct_limit_info); 1856 pr_err("openvswitch: failed to init nf_conncount %d\n", err); 1857 return err; 1858 } 1859 return 0; 1860 } 1861 1862 static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net) 1863 { 1864 const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info; 1865 int i; 1866 1867 nf_conncount_destroy(net, NFPROTO_INET, info->data); 1868 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 1869 struct hlist_head *head = &info->limits[i]; 1870 struct ovs_ct_limit *ct_limit; 1871 1872 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) 1873 kfree_rcu(ct_limit, rcu); 1874 } 1875 kfree(ovs_net->ct_limit_info->limits); 1876 kfree(ovs_net->ct_limit_info); 1877 } 1878 1879 static struct sk_buff * 1880 ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd, 1881 struct ovs_header **ovs_reply_header) 1882 { 1883 struct ovs_header *ovs_header = info->userhdr; 1884 struct sk_buff *skb; 1885 1886 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1887 if (!skb) 1888 return ERR_PTR(-ENOMEM); 1889 1890 *ovs_reply_header = genlmsg_put(skb, info->snd_portid, 1891 info->snd_seq, 1892 &dp_ct_limit_genl_family, 0, cmd); 1893 1894 if (!*ovs_reply_header) { 1895 nlmsg_free(skb); 1896 return ERR_PTR(-EMSGSIZE); 1897 } 1898 (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex; 1899 1900 return skb; 1901 } 1902 1903 static bool check_zone_id(int zone_id, u16 *pzone) 1904 { 1905 if (zone_id >= 0 && zone_id <= 65535) { 1906 *pzone = (u16)zone_id; 1907 return true; 1908 } 1909 return false; 1910 } 1911 1912 static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit, 1913 struct ovs_ct_limit_info *info) 1914 { 1915 struct ovs_zone_limit *zone_limit; 1916 int rem; 1917 u16 zone; 1918 1919 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1920 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1921 1922 while (rem >= sizeof(*zone_limit)) { 1923 if (unlikely(zone_limit->zone_id == 1924 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1925 ovs_lock(); 1926 info->default_limit = zone_limit->limit; 1927 ovs_unlock(); 1928 } else if (unlikely(!check_zone_id( 1929 zone_limit->zone_id, &zone))) { 1930 OVS_NLERR(true, "zone id is out of range"); 1931 } else { 1932 struct ovs_ct_limit *ct_limit; 1933 1934 ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL); 1935 if (!ct_limit) 1936 return -ENOMEM; 1937 1938 ct_limit->zone = zone; 1939 ct_limit->limit = zone_limit->limit; 1940 1941 ovs_lock(); 1942 ct_limit_set(info, ct_limit); 1943 ovs_unlock(); 1944 } 1945 rem -= NLA_ALIGN(sizeof(*zone_limit)); 1946 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 1947 NLA_ALIGN(sizeof(*zone_limit))); 1948 } 1949 1950 if (rem) 1951 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem); 1952 1953 return 0; 1954 } 1955 1956 static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit, 1957 struct ovs_ct_limit_info *info) 1958 { 1959 struct ovs_zone_limit *zone_limit; 1960 int rem; 1961 u16 zone; 1962 1963 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1964 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1965 1966 while (rem >= sizeof(*zone_limit)) { 1967 if (unlikely(zone_limit->zone_id == 1968 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1969 ovs_lock(); 1970 info->default_limit = OVS_CT_LIMIT_DEFAULT; 1971 ovs_unlock(); 1972 } else if (unlikely(!check_zone_id( 1973 zone_limit->zone_id, &zone))) { 1974 OVS_NLERR(true, "zone id is out of range"); 1975 } else { 1976 ovs_lock(); 1977 ct_limit_del(info, zone); 1978 ovs_unlock(); 1979 } 1980 rem -= NLA_ALIGN(sizeof(*zone_limit)); 1981 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 1982 NLA_ALIGN(sizeof(*zone_limit))); 1983 } 1984 1985 if (rem) 1986 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem); 1987 1988 return 0; 1989 } 1990 1991 static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info, 1992 struct sk_buff *reply) 1993 { 1994 struct ovs_zone_limit zone_limit; 1995 int err; 1996 1997 zone_limit.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE; 1998 zone_limit.limit = info->default_limit; 1999 err = nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 2000 if (err) 2001 return err; 2002 2003 return 0; 2004 } 2005 2006 static int __ovs_ct_limit_get_zone_limit(struct net *net, 2007 struct nf_conncount_data *data, 2008 u16 zone_id, u32 limit, 2009 struct sk_buff *reply) 2010 { 2011 struct nf_conntrack_zone ct_zone; 2012 struct ovs_zone_limit zone_limit; 2013 u32 conncount_key = zone_id; 2014 2015 zone_limit.zone_id = zone_id; 2016 zone_limit.limit = limit; 2017 nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0); 2018 2019 zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL, 2020 &ct_zone); 2021 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 2022 } 2023 2024 static int ovs_ct_limit_get_zone_limit(struct net *net, 2025 struct nlattr *nla_zone_limit, 2026 struct ovs_ct_limit_info *info, 2027 struct sk_buff *reply) 2028 { 2029 struct ovs_zone_limit *zone_limit; 2030 int rem, err; 2031 u32 limit; 2032 u16 zone; 2033 2034 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 2035 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 2036 2037 while (rem >= sizeof(*zone_limit)) { 2038 if (unlikely(zone_limit->zone_id == 2039 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 2040 err = ovs_ct_limit_get_default_limit(info, reply); 2041 if (err) 2042 return err; 2043 } else if (unlikely(!check_zone_id(zone_limit->zone_id, 2044 &zone))) { 2045 OVS_NLERR(true, "zone id is out of range"); 2046 } else { 2047 rcu_read_lock(); 2048 limit = ct_limit_get(info, zone); 2049 rcu_read_unlock(); 2050 2051 err = __ovs_ct_limit_get_zone_limit( 2052 net, info->data, zone, limit, reply); 2053 if (err) 2054 return err; 2055 } 2056 rem -= NLA_ALIGN(sizeof(*zone_limit)); 2057 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 2058 NLA_ALIGN(sizeof(*zone_limit))); 2059 } 2060 2061 if (rem) 2062 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem); 2063 2064 return 0; 2065 } 2066 2067 static int ovs_ct_limit_get_all_zone_limit(struct net *net, 2068 struct ovs_ct_limit_info *info, 2069 struct sk_buff *reply) 2070 { 2071 struct ovs_ct_limit *ct_limit; 2072 struct hlist_head *head; 2073 int i, err = 0; 2074 2075 err = ovs_ct_limit_get_default_limit(info, reply); 2076 if (err) 2077 return err; 2078 2079 rcu_read_lock(); 2080 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 2081 head = &info->limits[i]; 2082 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 2083 err = __ovs_ct_limit_get_zone_limit(net, info->data, 2084 ct_limit->zone, ct_limit->limit, reply); 2085 if (err) 2086 goto exit_err; 2087 } 2088 } 2089 2090 exit_err: 2091 rcu_read_unlock(); 2092 return err; 2093 } 2094 2095 static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info) 2096 { 2097 struct nlattr **a = info->attrs; 2098 struct sk_buff *reply; 2099 struct ovs_header *ovs_reply_header; 2100 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2101 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2102 int err; 2103 2104 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET, 2105 &ovs_reply_header); 2106 if (IS_ERR(reply)) 2107 return PTR_ERR(reply); 2108 2109 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2110 err = -EINVAL; 2111 goto exit_err; 2112 } 2113 2114 err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2115 ct_limit_info); 2116 if (err) 2117 goto exit_err; 2118 2119 static_branch_enable(&ovs_ct_limit_enabled); 2120 2121 genlmsg_end(reply, ovs_reply_header); 2122 return genlmsg_reply(reply, info); 2123 2124 exit_err: 2125 nlmsg_free(reply); 2126 return err; 2127 } 2128 2129 static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info) 2130 { 2131 struct nlattr **a = info->attrs; 2132 struct sk_buff *reply; 2133 struct ovs_header *ovs_reply_header; 2134 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2135 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2136 int err; 2137 2138 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL, 2139 &ovs_reply_header); 2140 if (IS_ERR(reply)) 2141 return PTR_ERR(reply); 2142 2143 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2144 err = -EINVAL; 2145 goto exit_err; 2146 } 2147 2148 err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2149 ct_limit_info); 2150 if (err) 2151 goto exit_err; 2152 2153 genlmsg_end(reply, ovs_reply_header); 2154 return genlmsg_reply(reply, info); 2155 2156 exit_err: 2157 nlmsg_free(reply); 2158 return err; 2159 } 2160 2161 static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info) 2162 { 2163 struct nlattr **a = info->attrs; 2164 struct nlattr *nla_reply; 2165 struct sk_buff *reply; 2166 struct ovs_header *ovs_reply_header; 2167 struct net *net = sock_net(skb->sk); 2168 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2169 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2170 int err; 2171 2172 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET, 2173 &ovs_reply_header); 2174 if (IS_ERR(reply)) 2175 return PTR_ERR(reply); 2176 2177 nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT); 2178 if (!nla_reply) { 2179 err = -EMSGSIZE; 2180 goto exit_err; 2181 } 2182 2183 if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2184 err = ovs_ct_limit_get_zone_limit( 2185 net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info, 2186 reply); 2187 if (err) 2188 goto exit_err; 2189 } else { 2190 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info, 2191 reply); 2192 if (err) 2193 goto exit_err; 2194 } 2195 2196 nla_nest_end(reply, nla_reply); 2197 genlmsg_end(reply, ovs_reply_header); 2198 return genlmsg_reply(reply, info); 2199 2200 exit_err: 2201 nlmsg_free(reply); 2202 return err; 2203 } 2204 2205 static struct genl_ops ct_limit_genl_ops[] = { 2206 { .cmd = OVS_CT_LIMIT_CMD_SET, 2207 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2208 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2209 * privilege. */ 2210 .doit = ovs_ct_limit_cmd_set, 2211 }, 2212 { .cmd = OVS_CT_LIMIT_CMD_DEL, 2213 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2214 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2215 * privilege. */ 2216 .doit = ovs_ct_limit_cmd_del, 2217 }, 2218 { .cmd = OVS_CT_LIMIT_CMD_GET, 2219 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP, 2220 .flags = 0, /* OK for unprivileged users. */ 2221 .doit = ovs_ct_limit_cmd_get, 2222 }, 2223 }; 2224 2225 static const struct genl_multicast_group ovs_ct_limit_multicast_group = { 2226 .name = OVS_CT_LIMIT_MCGROUP, 2227 }; 2228 2229 struct genl_family dp_ct_limit_genl_family __ro_after_init = { 2230 .hdrsize = sizeof(struct ovs_header), 2231 .name = OVS_CT_LIMIT_FAMILY, 2232 .version = OVS_CT_LIMIT_VERSION, 2233 .maxattr = OVS_CT_LIMIT_ATTR_MAX, 2234 .policy = ct_limit_policy, 2235 .netnsok = true, 2236 .parallel_ops = true, 2237 .ops = ct_limit_genl_ops, 2238 .n_ops = ARRAY_SIZE(ct_limit_genl_ops), 2239 .mcgrps = &ovs_ct_limit_multicast_group, 2240 .n_mcgrps = 1, 2241 .module = THIS_MODULE, 2242 }; 2243 #endif 2244 2245 int ovs_ct_init(struct net *net) 2246 { 2247 unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE; 2248 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2249 2250 if (nf_connlabels_get(net, n_bits - 1)) { 2251 ovs_net->xt_label = false; 2252 OVS_NLERR(true, "Failed to set connlabel length"); 2253 } else { 2254 ovs_net->xt_label = true; 2255 } 2256 2257 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2258 return ovs_ct_limit_init(net, ovs_net); 2259 #else 2260 return 0; 2261 #endif 2262 } 2263 2264 void ovs_ct_exit(struct net *net) 2265 { 2266 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2267 2268 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2269 ovs_ct_limit_exit(net, ovs_net); 2270 #endif 2271 2272 if (ovs_net->xt_label) 2273 nf_connlabels_put(net); 2274 } 2275