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_zones.h> 28 #include <net/netfilter/ipv6/nf_defrag_ipv6.h> 29 #include <net/ipv6_frag.h> 30 31 #ifdef CONFIG_NF_NAT_NEEDED 32 #include <linux/netfilter/nf_nat.h> 33 #include <net/netfilter/nf_nat_core.h> 34 #include <net/netfilter/nf_nat_l3proto.h> 35 #endif 36 37 #include "datapath.h" 38 #include "conntrack.h" 39 #include "flow.h" 40 #include "flow_netlink.h" 41 42 struct ovs_ct_len_tbl { 43 int maxlen; 44 int minlen; 45 }; 46 47 /* Metadata mark for masked write to conntrack mark */ 48 struct md_mark { 49 u32 value; 50 u32 mask; 51 }; 52 53 /* Metadata label for masked write to conntrack label. */ 54 struct md_labels { 55 struct ovs_key_ct_labels value; 56 struct ovs_key_ct_labels mask; 57 }; 58 59 enum ovs_ct_nat { 60 OVS_CT_NAT = 1 << 0, /* NAT for committed connections only. */ 61 OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */ 62 OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */ 63 }; 64 65 /* Conntrack action context for execution. */ 66 struct ovs_conntrack_info { 67 struct nf_conntrack_helper *helper; 68 struct nf_conntrack_zone zone; 69 struct nf_conn *ct; 70 u8 commit : 1; 71 u8 nat : 3; /* enum ovs_ct_nat */ 72 u8 force : 1; 73 u8 have_eventmask : 1; 74 u16 family; 75 u32 eventmask; /* Mask of 1 << IPCT_*. */ 76 struct md_mark mark; 77 struct md_labels labels; 78 #ifdef CONFIG_NF_NAT_NEEDED 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_tuplepr(&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 #ifdef CONFIG_NF_NAT_NEEDED 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_IPV4) && 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_NF_NAT_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_NEEDED */ 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 } 996 997 /* Call the helper only if: 998 * - nf_conntrack_in() was executed above ("!cached") for a 999 * confirmed connection, or 1000 * - When committing an unconfirmed connection. 1001 */ 1002 if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) && 1003 ovs_ct_helper(skb, info->family) != NF_ACCEPT) { 1004 return -EINVAL; 1005 } 1006 } 1007 1008 return 0; 1009 } 1010 1011 /* Lookup connection and read fields into key. */ 1012 static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key, 1013 const struct ovs_conntrack_info *info, 1014 struct sk_buff *skb) 1015 { 1016 struct nf_conntrack_expect *exp; 1017 1018 /* If we pass an expected packet through nf_conntrack_in() the 1019 * expectation is typically removed, but the packet could still be 1020 * lost in upcall processing. To prevent this from happening we 1021 * perform an explicit expectation lookup. Expected connections are 1022 * always new, and will be passed through conntrack only when they are 1023 * committed, as it is OK to remove the expectation at that time. 1024 */ 1025 exp = ovs_ct_expect_find(net, &info->zone, info->family, skb); 1026 if (exp) { 1027 u8 state; 1028 1029 /* NOTE: New connections are NATted and Helped only when 1030 * committed, so we are not calling into NAT here. 1031 */ 1032 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED; 1033 __ovs_ct_update_key(key, state, &info->zone, exp->master); 1034 } else { 1035 struct nf_conn *ct; 1036 int err; 1037 1038 err = __ovs_ct_lookup(net, key, info, skb); 1039 if (err) 1040 return err; 1041 1042 ct = (struct nf_conn *)skb_nfct(skb); 1043 if (ct) 1044 nf_ct_deliver_cached_events(ct); 1045 } 1046 1047 return 0; 1048 } 1049 1050 static bool labels_nonzero(const struct ovs_key_ct_labels *labels) 1051 { 1052 size_t i; 1053 1054 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) 1055 if (labels->ct_labels_32[i]) 1056 return true; 1057 1058 return false; 1059 } 1060 1061 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1062 static struct hlist_head *ct_limit_hash_bucket( 1063 const struct ovs_ct_limit_info *info, u16 zone) 1064 { 1065 return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)]; 1066 } 1067 1068 /* Call with ovs_mutex */ 1069 static void ct_limit_set(const struct ovs_ct_limit_info *info, 1070 struct ovs_ct_limit *new_ct_limit) 1071 { 1072 struct ovs_ct_limit *ct_limit; 1073 struct hlist_head *head; 1074 1075 head = ct_limit_hash_bucket(info, new_ct_limit->zone); 1076 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1077 if (ct_limit->zone == new_ct_limit->zone) { 1078 hlist_replace_rcu(&ct_limit->hlist_node, 1079 &new_ct_limit->hlist_node); 1080 kfree_rcu(ct_limit, rcu); 1081 return; 1082 } 1083 } 1084 1085 hlist_add_head_rcu(&new_ct_limit->hlist_node, head); 1086 } 1087 1088 /* Call with ovs_mutex */ 1089 static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone) 1090 { 1091 struct ovs_ct_limit *ct_limit; 1092 struct hlist_head *head; 1093 struct hlist_node *n; 1094 1095 head = ct_limit_hash_bucket(info, zone); 1096 hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) { 1097 if (ct_limit->zone == zone) { 1098 hlist_del_rcu(&ct_limit->hlist_node); 1099 kfree_rcu(ct_limit, rcu); 1100 return; 1101 } 1102 } 1103 } 1104 1105 /* Call with RCU read lock */ 1106 static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone) 1107 { 1108 struct ovs_ct_limit *ct_limit; 1109 struct hlist_head *head; 1110 1111 head = ct_limit_hash_bucket(info, zone); 1112 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1113 if (ct_limit->zone == zone) 1114 return ct_limit->limit; 1115 } 1116 1117 return info->default_limit; 1118 } 1119 1120 static int ovs_ct_check_limit(struct net *net, 1121 const struct ovs_conntrack_info *info, 1122 const struct nf_conntrack_tuple *tuple) 1123 { 1124 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1125 const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 1126 u32 per_zone_limit, connections; 1127 u32 conncount_key; 1128 1129 conncount_key = info->zone.id; 1130 1131 per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id); 1132 if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED) 1133 return 0; 1134 1135 connections = nf_conncount_count(net, ct_limit_info->data, 1136 &conncount_key, tuple, &info->zone); 1137 if (connections > per_zone_limit) 1138 return -ENOMEM; 1139 1140 return 0; 1141 } 1142 #endif 1143 1144 /* Lookup connection and confirm if unconfirmed. */ 1145 static int ovs_ct_commit(struct net *net, struct sw_flow_key *key, 1146 const struct ovs_conntrack_info *info, 1147 struct sk_buff *skb) 1148 { 1149 enum ip_conntrack_info ctinfo; 1150 struct nf_conn *ct; 1151 int err; 1152 1153 err = __ovs_ct_lookup(net, key, info, skb); 1154 if (err) 1155 return err; 1156 1157 /* The connection could be invalid, in which case this is a no-op.*/ 1158 ct = nf_ct_get(skb, &ctinfo); 1159 if (!ct) 1160 return 0; 1161 1162 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1163 if (static_branch_unlikely(&ovs_ct_limit_enabled)) { 1164 if (!nf_ct_is_confirmed(ct)) { 1165 err = ovs_ct_check_limit(net, info, 1166 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); 1167 if (err) { 1168 net_warn_ratelimited("openvswitch: zone: %u " 1169 "exceeds conntrack limit\n", 1170 info->zone.id); 1171 return err; 1172 } 1173 } 1174 } 1175 #endif 1176 1177 /* Set the conntrack event mask if given. NEW and DELETE events have 1178 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener 1179 * typically would receive many kinds of updates. Setting the event 1180 * mask allows those events to be filtered. The set event mask will 1181 * remain in effect for the lifetime of the connection unless changed 1182 * by a further CT action with both the commit flag and the eventmask 1183 * option. */ 1184 if (info->have_eventmask) { 1185 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct); 1186 1187 if (cache) 1188 cache->ctmask = info->eventmask; 1189 } 1190 1191 /* Apply changes before confirming the connection so that the initial 1192 * conntrack NEW netlink event carries the values given in the CT 1193 * action. 1194 */ 1195 if (info->mark.mask) { 1196 err = ovs_ct_set_mark(ct, key, info->mark.value, 1197 info->mark.mask); 1198 if (err) 1199 return err; 1200 } 1201 if (!nf_ct_is_confirmed(ct)) { 1202 err = ovs_ct_init_labels(ct, key, &info->labels.value, 1203 &info->labels.mask); 1204 if (err) 1205 return err; 1206 } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1207 labels_nonzero(&info->labels.mask)) { 1208 err = ovs_ct_set_labels(ct, key, &info->labels.value, 1209 &info->labels.mask); 1210 if (err) 1211 return err; 1212 } 1213 /* This will take care of sending queued events even if the connection 1214 * is already confirmed. 1215 */ 1216 if (nf_conntrack_confirm(skb) != NF_ACCEPT) 1217 return -EINVAL; 1218 1219 return 0; 1220 } 1221 1222 /* Trim the skb to the length specified by the IP/IPv6 header, 1223 * removing any trailing lower-layer padding. This prepares the skb 1224 * for higher-layer processing that assumes skb->len excludes padding 1225 * (such as nf_ip_checksum). The caller needs to pull the skb to the 1226 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 1227 */ 1228 static int ovs_skb_network_trim(struct sk_buff *skb) 1229 { 1230 unsigned int len; 1231 int err; 1232 1233 switch (skb->protocol) { 1234 case htons(ETH_P_IP): 1235 len = ntohs(ip_hdr(skb)->tot_len); 1236 break; 1237 case htons(ETH_P_IPV6): 1238 len = sizeof(struct ipv6hdr) 1239 + ntohs(ipv6_hdr(skb)->payload_len); 1240 break; 1241 default: 1242 len = skb->len; 1243 } 1244 1245 err = pskb_trim_rcsum(skb, len); 1246 if (err) 1247 kfree_skb(skb); 1248 1249 return err; 1250 } 1251 1252 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero 1253 * value if 'skb' is freed. 1254 */ 1255 int ovs_ct_execute(struct net *net, struct sk_buff *skb, 1256 struct sw_flow_key *key, 1257 const struct ovs_conntrack_info *info) 1258 { 1259 int nh_ofs; 1260 int err; 1261 1262 /* The conntrack module expects to be working at L3. */ 1263 nh_ofs = skb_network_offset(skb); 1264 skb_pull_rcsum(skb, nh_ofs); 1265 1266 err = ovs_skb_network_trim(skb); 1267 if (err) 1268 return err; 1269 1270 if (key->ip.frag != OVS_FRAG_TYPE_NONE) { 1271 err = handle_fragments(net, key, info->zone.id, skb); 1272 if (err) 1273 return err; 1274 } 1275 1276 if (info->commit) 1277 err = ovs_ct_commit(net, key, info, skb); 1278 else 1279 err = ovs_ct_lookup(net, key, info, skb); 1280 1281 skb_push(skb, nh_ofs); 1282 skb_postpush_rcsum(skb, skb->data, nh_ofs); 1283 if (err) 1284 kfree_skb(skb); 1285 return err; 1286 } 1287 1288 int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key) 1289 { 1290 if (skb_nfct(skb)) { 1291 nf_conntrack_put(skb_nfct(skb)); 1292 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 1293 ovs_ct_fill_key(skb, key); 1294 } 1295 1296 return 0; 1297 } 1298 1299 static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name, 1300 const struct sw_flow_key *key, bool log) 1301 { 1302 struct nf_conntrack_helper *helper; 1303 struct nf_conn_help *help; 1304 1305 helper = nf_conntrack_helper_try_module_get(name, info->family, 1306 key->ip.proto); 1307 if (!helper) { 1308 OVS_NLERR(log, "Unknown helper \"%s\"", name); 1309 return -EINVAL; 1310 } 1311 1312 help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL); 1313 if (!help) { 1314 nf_conntrack_helper_put(helper); 1315 return -ENOMEM; 1316 } 1317 1318 rcu_assign_pointer(help->helper, helper); 1319 info->helper = helper; 1320 1321 if (info->nat) 1322 request_module("ip_nat_%s", name); 1323 1324 return 0; 1325 } 1326 1327 #ifdef CONFIG_NF_NAT_NEEDED 1328 static int parse_nat(const struct nlattr *attr, 1329 struct ovs_conntrack_info *info, bool log) 1330 { 1331 struct nlattr *a; 1332 int rem; 1333 bool have_ip_max = false; 1334 bool have_proto_max = false; 1335 bool ip_vers = (info->family == NFPROTO_IPV6); 1336 1337 nla_for_each_nested(a, attr, rem) { 1338 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = { 1339 [OVS_NAT_ATTR_SRC] = {0, 0}, 1340 [OVS_NAT_ATTR_DST] = {0, 0}, 1341 [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr), 1342 sizeof(struct in6_addr)}, 1343 [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr), 1344 sizeof(struct in6_addr)}, 1345 [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)}, 1346 [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)}, 1347 [OVS_NAT_ATTR_PERSISTENT] = {0, 0}, 1348 [OVS_NAT_ATTR_PROTO_HASH] = {0, 0}, 1349 [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0}, 1350 }; 1351 int type = nla_type(a); 1352 1353 if (type > OVS_NAT_ATTR_MAX) { 1354 OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)", 1355 type, OVS_NAT_ATTR_MAX); 1356 return -EINVAL; 1357 } 1358 1359 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) { 1360 OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)", 1361 type, nla_len(a), 1362 ovs_nat_attr_lens[type][ip_vers]); 1363 return -EINVAL; 1364 } 1365 1366 switch (type) { 1367 case OVS_NAT_ATTR_SRC: 1368 case OVS_NAT_ATTR_DST: 1369 if (info->nat) { 1370 OVS_NLERR(log, "Only one type of NAT may be specified"); 1371 return -ERANGE; 1372 } 1373 info->nat |= OVS_CT_NAT; 1374 info->nat |= ((type == OVS_NAT_ATTR_SRC) 1375 ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT); 1376 break; 1377 1378 case OVS_NAT_ATTR_IP_MIN: 1379 nla_memcpy(&info->range.min_addr, a, 1380 sizeof(info->range.min_addr)); 1381 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1382 break; 1383 1384 case OVS_NAT_ATTR_IP_MAX: 1385 have_ip_max = true; 1386 nla_memcpy(&info->range.max_addr, a, 1387 sizeof(info->range.max_addr)); 1388 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1389 break; 1390 1391 case OVS_NAT_ATTR_PROTO_MIN: 1392 info->range.min_proto.all = htons(nla_get_u16(a)); 1393 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1394 break; 1395 1396 case OVS_NAT_ATTR_PROTO_MAX: 1397 have_proto_max = true; 1398 info->range.max_proto.all = htons(nla_get_u16(a)); 1399 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1400 break; 1401 1402 case OVS_NAT_ATTR_PERSISTENT: 1403 info->range.flags |= NF_NAT_RANGE_PERSISTENT; 1404 break; 1405 1406 case OVS_NAT_ATTR_PROTO_HASH: 1407 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM; 1408 break; 1409 1410 case OVS_NAT_ATTR_PROTO_RANDOM: 1411 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY; 1412 break; 1413 1414 default: 1415 OVS_NLERR(log, "Unknown nat attribute (%d)", type); 1416 return -EINVAL; 1417 } 1418 } 1419 1420 if (rem > 0) { 1421 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem); 1422 return -EINVAL; 1423 } 1424 if (!info->nat) { 1425 /* Do not allow flags if no type is given. */ 1426 if (info->range.flags) { 1427 OVS_NLERR(log, 1428 "NAT flags may be given only when NAT range (SRC or DST) is also specified." 1429 ); 1430 return -EINVAL; 1431 } 1432 info->nat = OVS_CT_NAT; /* NAT existing connections. */ 1433 } else if (!info->commit) { 1434 OVS_NLERR(log, 1435 "NAT attributes may be specified only when CT COMMIT flag is also specified." 1436 ); 1437 return -EINVAL; 1438 } 1439 /* Allow missing IP_MAX. */ 1440 if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) { 1441 memcpy(&info->range.max_addr, &info->range.min_addr, 1442 sizeof(info->range.max_addr)); 1443 } 1444 /* Allow missing PROTO_MAX. */ 1445 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1446 !have_proto_max) { 1447 info->range.max_proto.all = info->range.min_proto.all; 1448 } 1449 return 0; 1450 } 1451 #endif 1452 1453 static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = { 1454 [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1455 [OVS_CT_ATTR_FORCE_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1456 [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16), 1457 .maxlen = sizeof(u16) }, 1458 [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark), 1459 .maxlen = sizeof(struct md_mark) }, 1460 [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels), 1461 .maxlen = sizeof(struct md_labels) }, 1462 [OVS_CT_ATTR_HELPER] = { .minlen = 1, 1463 .maxlen = NF_CT_HELPER_NAME_LEN }, 1464 #ifdef CONFIG_NF_NAT_NEEDED 1465 /* NAT length is checked when parsing the nested attributes. */ 1466 [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX }, 1467 #endif 1468 [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32), 1469 .maxlen = sizeof(u32) }, 1470 }; 1471 1472 static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info, 1473 const char **helper, bool log) 1474 { 1475 struct nlattr *a; 1476 int rem; 1477 1478 nla_for_each_nested(a, attr, rem) { 1479 int type = nla_type(a); 1480 int maxlen; 1481 int minlen; 1482 1483 if (type > OVS_CT_ATTR_MAX) { 1484 OVS_NLERR(log, 1485 "Unknown conntrack attr (type=%d, max=%d)", 1486 type, OVS_CT_ATTR_MAX); 1487 return -EINVAL; 1488 } 1489 1490 maxlen = ovs_ct_attr_lens[type].maxlen; 1491 minlen = ovs_ct_attr_lens[type].minlen; 1492 if (nla_len(a) < minlen || nla_len(a) > maxlen) { 1493 OVS_NLERR(log, 1494 "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)", 1495 type, nla_len(a), maxlen); 1496 return -EINVAL; 1497 } 1498 1499 switch (type) { 1500 case OVS_CT_ATTR_FORCE_COMMIT: 1501 info->force = true; 1502 /* fall through. */ 1503 case OVS_CT_ATTR_COMMIT: 1504 info->commit = true; 1505 break; 1506 #ifdef CONFIG_NF_CONNTRACK_ZONES 1507 case OVS_CT_ATTR_ZONE: 1508 info->zone.id = nla_get_u16(a); 1509 break; 1510 #endif 1511 #ifdef CONFIG_NF_CONNTRACK_MARK 1512 case OVS_CT_ATTR_MARK: { 1513 struct md_mark *mark = nla_data(a); 1514 1515 if (!mark->mask) { 1516 OVS_NLERR(log, "ct_mark mask cannot be 0"); 1517 return -EINVAL; 1518 } 1519 info->mark = *mark; 1520 break; 1521 } 1522 #endif 1523 #ifdef CONFIG_NF_CONNTRACK_LABELS 1524 case OVS_CT_ATTR_LABELS: { 1525 struct md_labels *labels = nla_data(a); 1526 1527 if (!labels_nonzero(&labels->mask)) { 1528 OVS_NLERR(log, "ct_labels mask cannot be 0"); 1529 return -EINVAL; 1530 } 1531 info->labels = *labels; 1532 break; 1533 } 1534 #endif 1535 case OVS_CT_ATTR_HELPER: 1536 *helper = nla_data(a); 1537 if (!memchr(*helper, '\0', nla_len(a))) { 1538 OVS_NLERR(log, "Invalid conntrack helper"); 1539 return -EINVAL; 1540 } 1541 break; 1542 #ifdef CONFIG_NF_NAT_NEEDED 1543 case OVS_CT_ATTR_NAT: { 1544 int err = parse_nat(a, info, log); 1545 1546 if (err) 1547 return err; 1548 break; 1549 } 1550 #endif 1551 case OVS_CT_ATTR_EVENTMASK: 1552 info->have_eventmask = true; 1553 info->eventmask = nla_get_u32(a); 1554 break; 1555 1556 default: 1557 OVS_NLERR(log, "Unknown conntrack attr (%d)", 1558 type); 1559 return -EINVAL; 1560 } 1561 } 1562 1563 #ifdef CONFIG_NF_CONNTRACK_MARK 1564 if (!info->commit && info->mark.mask) { 1565 OVS_NLERR(log, 1566 "Setting conntrack mark requires 'commit' flag."); 1567 return -EINVAL; 1568 } 1569 #endif 1570 #ifdef CONFIG_NF_CONNTRACK_LABELS 1571 if (!info->commit && labels_nonzero(&info->labels.mask)) { 1572 OVS_NLERR(log, 1573 "Setting conntrack labels requires 'commit' flag."); 1574 return -EINVAL; 1575 } 1576 #endif 1577 if (rem > 0) { 1578 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem); 1579 return -EINVAL; 1580 } 1581 1582 return 0; 1583 } 1584 1585 bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr) 1586 { 1587 if (attr == OVS_KEY_ATTR_CT_STATE) 1588 return true; 1589 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1590 attr == OVS_KEY_ATTR_CT_ZONE) 1591 return true; 1592 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1593 attr == OVS_KEY_ATTR_CT_MARK) 1594 return true; 1595 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1596 attr == OVS_KEY_ATTR_CT_LABELS) { 1597 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1598 1599 return ovs_net->xt_label; 1600 } 1601 1602 return false; 1603 } 1604 1605 int ovs_ct_copy_action(struct net *net, const struct nlattr *attr, 1606 const struct sw_flow_key *key, 1607 struct sw_flow_actions **sfa, bool log) 1608 { 1609 struct ovs_conntrack_info ct_info; 1610 const char *helper = NULL; 1611 u16 family; 1612 int err; 1613 1614 family = key_to_nfproto(key); 1615 if (family == NFPROTO_UNSPEC) { 1616 OVS_NLERR(log, "ct family unspecified"); 1617 return -EINVAL; 1618 } 1619 1620 memset(&ct_info, 0, sizeof(ct_info)); 1621 ct_info.family = family; 1622 1623 nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID, 1624 NF_CT_DEFAULT_ZONE_DIR, 0); 1625 1626 err = parse_ct(attr, &ct_info, &helper, log); 1627 if (err) 1628 return err; 1629 1630 /* Set up template for tracking connections in specific zones. */ 1631 ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL); 1632 if (!ct_info.ct) { 1633 OVS_NLERR(log, "Failed to allocate conntrack template"); 1634 return -ENOMEM; 1635 } 1636 if (helper) { 1637 err = ovs_ct_add_helper(&ct_info, helper, key, log); 1638 if (err) 1639 goto err_free_ct; 1640 } 1641 1642 err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info, 1643 sizeof(ct_info), log); 1644 if (err) 1645 goto err_free_ct; 1646 1647 __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status); 1648 nf_conntrack_get(&ct_info.ct->ct_general); 1649 return 0; 1650 err_free_ct: 1651 __ovs_ct_free_action(&ct_info); 1652 return err; 1653 } 1654 1655 #ifdef CONFIG_NF_NAT_NEEDED 1656 static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, 1657 struct sk_buff *skb) 1658 { 1659 struct nlattr *start; 1660 1661 start = nla_nest_start(skb, OVS_CT_ATTR_NAT); 1662 if (!start) 1663 return false; 1664 1665 if (info->nat & OVS_CT_SRC_NAT) { 1666 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC)) 1667 return false; 1668 } else if (info->nat & OVS_CT_DST_NAT) { 1669 if (nla_put_flag(skb, OVS_NAT_ATTR_DST)) 1670 return false; 1671 } else { 1672 goto out; 1673 } 1674 1675 if (info->range.flags & NF_NAT_RANGE_MAP_IPS) { 1676 if (IS_ENABLED(CONFIG_NF_NAT_IPV4) && 1677 info->family == NFPROTO_IPV4) { 1678 if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN, 1679 info->range.min_addr.ip) || 1680 (info->range.max_addr.ip 1681 != info->range.min_addr.ip && 1682 (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX, 1683 info->range.max_addr.ip)))) 1684 return false; 1685 } else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) && 1686 info->family == NFPROTO_IPV6) { 1687 if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN, 1688 &info->range.min_addr.in6) || 1689 (memcmp(&info->range.max_addr.in6, 1690 &info->range.min_addr.in6, 1691 sizeof(info->range.max_addr.in6)) && 1692 (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX, 1693 &info->range.max_addr.in6)))) 1694 return false; 1695 } else { 1696 return false; 1697 } 1698 } 1699 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1700 (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN, 1701 ntohs(info->range.min_proto.all)) || 1702 (info->range.max_proto.all != info->range.min_proto.all && 1703 nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX, 1704 ntohs(info->range.max_proto.all))))) 1705 return false; 1706 1707 if (info->range.flags & NF_NAT_RANGE_PERSISTENT && 1708 nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT)) 1709 return false; 1710 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM && 1711 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH)) 1712 return false; 1713 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY && 1714 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM)) 1715 return false; 1716 out: 1717 nla_nest_end(skb, start); 1718 1719 return true; 1720 } 1721 #endif 1722 1723 int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info, 1724 struct sk_buff *skb) 1725 { 1726 struct nlattr *start; 1727 1728 start = nla_nest_start(skb, OVS_ACTION_ATTR_CT); 1729 if (!start) 1730 return -EMSGSIZE; 1731 1732 if (ct_info->commit && nla_put_flag(skb, ct_info->force 1733 ? OVS_CT_ATTR_FORCE_COMMIT 1734 : OVS_CT_ATTR_COMMIT)) 1735 return -EMSGSIZE; 1736 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1737 nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id)) 1738 return -EMSGSIZE; 1739 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask && 1740 nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark), 1741 &ct_info->mark)) 1742 return -EMSGSIZE; 1743 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1744 labels_nonzero(&ct_info->labels.mask) && 1745 nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels), 1746 &ct_info->labels)) 1747 return -EMSGSIZE; 1748 if (ct_info->helper) { 1749 if (nla_put_string(skb, OVS_CT_ATTR_HELPER, 1750 ct_info->helper->name)) 1751 return -EMSGSIZE; 1752 } 1753 if (ct_info->have_eventmask && 1754 nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask)) 1755 return -EMSGSIZE; 1756 1757 #ifdef CONFIG_NF_NAT_NEEDED 1758 if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb)) 1759 return -EMSGSIZE; 1760 #endif 1761 nla_nest_end(skb, start); 1762 1763 return 0; 1764 } 1765 1766 void ovs_ct_free_action(const struct nlattr *a) 1767 { 1768 struct ovs_conntrack_info *ct_info = nla_data(a); 1769 1770 __ovs_ct_free_action(ct_info); 1771 } 1772 1773 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info) 1774 { 1775 if (ct_info->helper) 1776 nf_conntrack_helper_put(ct_info->helper); 1777 if (ct_info->ct) 1778 nf_ct_tmpl_free(ct_info->ct); 1779 } 1780 1781 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1782 static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net) 1783 { 1784 int i, err; 1785 1786 ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info), 1787 GFP_KERNEL); 1788 if (!ovs_net->ct_limit_info) 1789 return -ENOMEM; 1790 1791 ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT; 1792 ovs_net->ct_limit_info->limits = 1793 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head), 1794 GFP_KERNEL); 1795 if (!ovs_net->ct_limit_info->limits) { 1796 kfree(ovs_net->ct_limit_info); 1797 return -ENOMEM; 1798 } 1799 1800 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++) 1801 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]); 1802 1803 ovs_net->ct_limit_info->data = 1804 nf_conncount_init(net, NFPROTO_INET, sizeof(u32)); 1805 1806 if (IS_ERR(ovs_net->ct_limit_info->data)) { 1807 err = PTR_ERR(ovs_net->ct_limit_info->data); 1808 kfree(ovs_net->ct_limit_info->limits); 1809 kfree(ovs_net->ct_limit_info); 1810 pr_err("openvswitch: failed to init nf_conncount %d\n", err); 1811 return err; 1812 } 1813 return 0; 1814 } 1815 1816 static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net) 1817 { 1818 const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info; 1819 int i; 1820 1821 nf_conncount_destroy(net, NFPROTO_INET, info->data); 1822 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 1823 struct hlist_head *head = &info->limits[i]; 1824 struct ovs_ct_limit *ct_limit; 1825 1826 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) 1827 kfree_rcu(ct_limit, rcu); 1828 } 1829 kfree(ovs_net->ct_limit_info->limits); 1830 kfree(ovs_net->ct_limit_info); 1831 } 1832 1833 static struct sk_buff * 1834 ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd, 1835 struct ovs_header **ovs_reply_header) 1836 { 1837 struct ovs_header *ovs_header = info->userhdr; 1838 struct sk_buff *skb; 1839 1840 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1841 if (!skb) 1842 return ERR_PTR(-ENOMEM); 1843 1844 *ovs_reply_header = genlmsg_put(skb, info->snd_portid, 1845 info->snd_seq, 1846 &dp_ct_limit_genl_family, 0, cmd); 1847 1848 if (!*ovs_reply_header) { 1849 nlmsg_free(skb); 1850 return ERR_PTR(-EMSGSIZE); 1851 } 1852 (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex; 1853 1854 return skb; 1855 } 1856 1857 static bool check_zone_id(int zone_id, u16 *pzone) 1858 { 1859 if (zone_id >= 0 && zone_id <= 65535) { 1860 *pzone = (u16)zone_id; 1861 return true; 1862 } 1863 return false; 1864 } 1865 1866 static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit, 1867 struct ovs_ct_limit_info *info) 1868 { 1869 struct ovs_zone_limit *zone_limit; 1870 int rem; 1871 u16 zone; 1872 1873 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1874 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1875 1876 while (rem >= sizeof(*zone_limit)) { 1877 if (unlikely(zone_limit->zone_id == 1878 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1879 ovs_lock(); 1880 info->default_limit = zone_limit->limit; 1881 ovs_unlock(); 1882 } else if (unlikely(!check_zone_id( 1883 zone_limit->zone_id, &zone))) { 1884 OVS_NLERR(true, "zone id is out of range"); 1885 } else { 1886 struct ovs_ct_limit *ct_limit; 1887 1888 ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL); 1889 if (!ct_limit) 1890 return -ENOMEM; 1891 1892 ct_limit->zone = zone; 1893 ct_limit->limit = zone_limit->limit; 1894 1895 ovs_lock(); 1896 ct_limit_set(info, ct_limit); 1897 ovs_unlock(); 1898 } 1899 rem -= NLA_ALIGN(sizeof(*zone_limit)); 1900 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 1901 NLA_ALIGN(sizeof(*zone_limit))); 1902 } 1903 1904 if (rem) 1905 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem); 1906 1907 return 0; 1908 } 1909 1910 static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit, 1911 struct ovs_ct_limit_info *info) 1912 { 1913 struct ovs_zone_limit *zone_limit; 1914 int rem; 1915 u16 zone; 1916 1917 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1918 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1919 1920 while (rem >= sizeof(*zone_limit)) { 1921 if (unlikely(zone_limit->zone_id == 1922 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1923 ovs_lock(); 1924 info->default_limit = OVS_CT_LIMIT_DEFAULT; 1925 ovs_unlock(); 1926 } else if (unlikely(!check_zone_id( 1927 zone_limit->zone_id, &zone))) { 1928 OVS_NLERR(true, "zone id is out of range"); 1929 } else { 1930 ovs_lock(); 1931 ct_limit_del(info, zone); 1932 ovs_unlock(); 1933 } 1934 rem -= NLA_ALIGN(sizeof(*zone_limit)); 1935 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 1936 NLA_ALIGN(sizeof(*zone_limit))); 1937 } 1938 1939 if (rem) 1940 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem); 1941 1942 return 0; 1943 } 1944 1945 static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info, 1946 struct sk_buff *reply) 1947 { 1948 struct ovs_zone_limit zone_limit; 1949 int err; 1950 1951 zone_limit.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE; 1952 zone_limit.limit = info->default_limit; 1953 err = nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 1954 if (err) 1955 return err; 1956 1957 return 0; 1958 } 1959 1960 static int __ovs_ct_limit_get_zone_limit(struct net *net, 1961 struct nf_conncount_data *data, 1962 u16 zone_id, u32 limit, 1963 struct sk_buff *reply) 1964 { 1965 struct nf_conntrack_zone ct_zone; 1966 struct ovs_zone_limit zone_limit; 1967 u32 conncount_key = zone_id; 1968 1969 zone_limit.zone_id = zone_id; 1970 zone_limit.limit = limit; 1971 nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0); 1972 1973 zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL, 1974 &ct_zone); 1975 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 1976 } 1977 1978 static int ovs_ct_limit_get_zone_limit(struct net *net, 1979 struct nlattr *nla_zone_limit, 1980 struct ovs_ct_limit_info *info, 1981 struct sk_buff *reply) 1982 { 1983 struct ovs_zone_limit *zone_limit; 1984 int rem, err; 1985 u32 limit; 1986 u16 zone; 1987 1988 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1989 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1990 1991 while (rem >= sizeof(*zone_limit)) { 1992 if (unlikely(zone_limit->zone_id == 1993 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1994 err = ovs_ct_limit_get_default_limit(info, reply); 1995 if (err) 1996 return err; 1997 } else if (unlikely(!check_zone_id(zone_limit->zone_id, 1998 &zone))) { 1999 OVS_NLERR(true, "zone id is out of range"); 2000 } else { 2001 rcu_read_lock(); 2002 limit = ct_limit_get(info, zone); 2003 rcu_read_unlock(); 2004 2005 err = __ovs_ct_limit_get_zone_limit( 2006 net, info->data, zone, limit, reply); 2007 if (err) 2008 return err; 2009 } 2010 rem -= NLA_ALIGN(sizeof(*zone_limit)); 2011 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 2012 NLA_ALIGN(sizeof(*zone_limit))); 2013 } 2014 2015 if (rem) 2016 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem); 2017 2018 return 0; 2019 } 2020 2021 static int ovs_ct_limit_get_all_zone_limit(struct net *net, 2022 struct ovs_ct_limit_info *info, 2023 struct sk_buff *reply) 2024 { 2025 struct ovs_ct_limit *ct_limit; 2026 struct hlist_head *head; 2027 int i, err = 0; 2028 2029 err = ovs_ct_limit_get_default_limit(info, reply); 2030 if (err) 2031 return err; 2032 2033 rcu_read_lock(); 2034 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 2035 head = &info->limits[i]; 2036 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 2037 err = __ovs_ct_limit_get_zone_limit(net, info->data, 2038 ct_limit->zone, ct_limit->limit, reply); 2039 if (err) 2040 goto exit_err; 2041 } 2042 } 2043 2044 exit_err: 2045 rcu_read_unlock(); 2046 return err; 2047 } 2048 2049 static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info) 2050 { 2051 struct nlattr **a = info->attrs; 2052 struct sk_buff *reply; 2053 struct ovs_header *ovs_reply_header; 2054 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2055 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2056 int err; 2057 2058 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET, 2059 &ovs_reply_header); 2060 if (IS_ERR(reply)) 2061 return PTR_ERR(reply); 2062 2063 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2064 err = -EINVAL; 2065 goto exit_err; 2066 } 2067 2068 err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2069 ct_limit_info); 2070 if (err) 2071 goto exit_err; 2072 2073 static_branch_enable(&ovs_ct_limit_enabled); 2074 2075 genlmsg_end(reply, ovs_reply_header); 2076 return genlmsg_reply(reply, info); 2077 2078 exit_err: 2079 nlmsg_free(reply); 2080 return err; 2081 } 2082 2083 static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info) 2084 { 2085 struct nlattr **a = info->attrs; 2086 struct sk_buff *reply; 2087 struct ovs_header *ovs_reply_header; 2088 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2089 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2090 int err; 2091 2092 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL, 2093 &ovs_reply_header); 2094 if (IS_ERR(reply)) 2095 return PTR_ERR(reply); 2096 2097 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2098 err = -EINVAL; 2099 goto exit_err; 2100 } 2101 2102 err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2103 ct_limit_info); 2104 if (err) 2105 goto exit_err; 2106 2107 genlmsg_end(reply, ovs_reply_header); 2108 return genlmsg_reply(reply, info); 2109 2110 exit_err: 2111 nlmsg_free(reply); 2112 return err; 2113 } 2114 2115 static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info) 2116 { 2117 struct nlattr **a = info->attrs; 2118 struct nlattr *nla_reply; 2119 struct sk_buff *reply; 2120 struct ovs_header *ovs_reply_header; 2121 struct net *net = sock_net(skb->sk); 2122 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2123 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2124 int err; 2125 2126 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET, 2127 &ovs_reply_header); 2128 if (IS_ERR(reply)) 2129 return PTR_ERR(reply); 2130 2131 nla_reply = nla_nest_start(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT); 2132 2133 if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2134 err = ovs_ct_limit_get_zone_limit( 2135 net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info, 2136 reply); 2137 if (err) 2138 goto exit_err; 2139 } else { 2140 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info, 2141 reply); 2142 if (err) 2143 goto exit_err; 2144 } 2145 2146 nla_nest_end(reply, nla_reply); 2147 genlmsg_end(reply, ovs_reply_header); 2148 return genlmsg_reply(reply, info); 2149 2150 exit_err: 2151 nlmsg_free(reply); 2152 return err; 2153 } 2154 2155 static struct genl_ops ct_limit_genl_ops[] = { 2156 { .cmd = OVS_CT_LIMIT_CMD_SET, 2157 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2158 * privilege. */ 2159 .policy = ct_limit_policy, 2160 .doit = ovs_ct_limit_cmd_set, 2161 }, 2162 { .cmd = OVS_CT_LIMIT_CMD_DEL, 2163 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2164 * privilege. */ 2165 .policy = ct_limit_policy, 2166 .doit = ovs_ct_limit_cmd_del, 2167 }, 2168 { .cmd = OVS_CT_LIMIT_CMD_GET, 2169 .flags = 0, /* OK for unprivileged users. */ 2170 .policy = ct_limit_policy, 2171 .doit = ovs_ct_limit_cmd_get, 2172 }, 2173 }; 2174 2175 static const struct genl_multicast_group ovs_ct_limit_multicast_group = { 2176 .name = OVS_CT_LIMIT_MCGROUP, 2177 }; 2178 2179 struct genl_family dp_ct_limit_genl_family __ro_after_init = { 2180 .hdrsize = sizeof(struct ovs_header), 2181 .name = OVS_CT_LIMIT_FAMILY, 2182 .version = OVS_CT_LIMIT_VERSION, 2183 .maxattr = OVS_CT_LIMIT_ATTR_MAX, 2184 .netnsok = true, 2185 .parallel_ops = true, 2186 .ops = ct_limit_genl_ops, 2187 .n_ops = ARRAY_SIZE(ct_limit_genl_ops), 2188 .mcgrps = &ovs_ct_limit_multicast_group, 2189 .n_mcgrps = 1, 2190 .module = THIS_MODULE, 2191 }; 2192 #endif 2193 2194 int ovs_ct_init(struct net *net) 2195 { 2196 unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE; 2197 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2198 2199 if (nf_connlabels_get(net, n_bits - 1)) { 2200 ovs_net->xt_label = false; 2201 OVS_NLERR(true, "Failed to set connlabel length"); 2202 } else { 2203 ovs_net->xt_label = true; 2204 } 2205 2206 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2207 return ovs_ct_limit_init(net, ovs_net); 2208 #else 2209 return 0; 2210 #endif 2211 } 2212 2213 void ovs_ct_exit(struct net *net) 2214 { 2215 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2216 2217 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2218 ovs_ct_limit_exit(net, ovs_net); 2219 #endif 2220 2221 if (ovs_net->xt_label) 2222 nf_connlabels_put(net); 2223 } 2224