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_conn *tmpl = info->ct; 937 int err; 938 939 /* Associate skb with specified zone. */ 940 if (tmpl) { 941 if (skb_nfct(skb)) 942 nf_conntrack_put(skb_nfct(skb)); 943 nf_conntrack_get(&tmpl->ct_general); 944 nf_ct_set(skb, tmpl, IP_CT_NEW); 945 } 946 947 err = nf_conntrack_in(net, info->family, 948 NF_INET_PRE_ROUTING, skb); 949 if (err != NF_ACCEPT) 950 return -ENOENT; 951 952 /* Clear CT state NAT flags to mark that we have not yet done 953 * NAT after the nf_conntrack_in() call. We can actually clear 954 * the whole state, as it will be re-initialized below. 955 */ 956 key->ct_state = 0; 957 958 /* Update the key, but keep the NAT flags. */ 959 ovs_ct_update_key(skb, info, key, true, true); 960 } 961 962 ct = nf_ct_get(skb, &ctinfo); 963 if (ct) { 964 /* Packets starting a new connection must be NATted before the 965 * helper, so that the helper knows about the NAT. We enforce 966 * this by delaying both NAT and helper calls for unconfirmed 967 * connections until the committing CT action. For later 968 * packets NAT and Helper may be called in either order. 969 * 970 * NAT will be done only if the CT action has NAT, and only 971 * once per packet (per zone), as guarded by the NAT bits in 972 * the key->ct_state. 973 */ 974 if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) && 975 (nf_ct_is_confirmed(ct) || info->commit) && 976 ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) { 977 return -EINVAL; 978 } 979 980 /* Userspace may decide to perform a ct lookup without a helper 981 * specified followed by a (recirculate and) commit with one. 982 * Therefore, for unconfirmed connections which we will commit, 983 * we need to attach the helper here. 984 */ 985 if (!nf_ct_is_confirmed(ct) && info->commit && 986 info->helper && !nfct_help(ct)) { 987 int err = __nf_ct_try_assign_helper(ct, info->ct, 988 GFP_ATOMIC); 989 if (err) 990 return err; 991 } 992 993 /* Call the helper only if: 994 * - nf_conntrack_in() was executed above ("!cached") for a 995 * confirmed connection, or 996 * - When committing an unconfirmed connection. 997 */ 998 if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) && 999 ovs_ct_helper(skb, info->family) != NF_ACCEPT) { 1000 return -EINVAL; 1001 } 1002 } 1003 1004 return 0; 1005 } 1006 1007 /* Lookup connection and read fields into key. */ 1008 static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key, 1009 const struct ovs_conntrack_info *info, 1010 struct sk_buff *skb) 1011 { 1012 struct nf_conntrack_expect *exp; 1013 1014 /* If we pass an expected packet through nf_conntrack_in() the 1015 * expectation is typically removed, but the packet could still be 1016 * lost in upcall processing. To prevent this from happening we 1017 * perform an explicit expectation lookup. Expected connections are 1018 * always new, and will be passed through conntrack only when they are 1019 * committed, as it is OK to remove the expectation at that time. 1020 */ 1021 exp = ovs_ct_expect_find(net, &info->zone, info->family, skb); 1022 if (exp) { 1023 u8 state; 1024 1025 /* NOTE: New connections are NATted and Helped only when 1026 * committed, so we are not calling into NAT here. 1027 */ 1028 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED; 1029 __ovs_ct_update_key(key, state, &info->zone, exp->master); 1030 } else { 1031 struct nf_conn *ct; 1032 int err; 1033 1034 err = __ovs_ct_lookup(net, key, info, skb); 1035 if (err) 1036 return err; 1037 1038 ct = (struct nf_conn *)skb_nfct(skb); 1039 if (ct) 1040 nf_ct_deliver_cached_events(ct); 1041 } 1042 1043 return 0; 1044 } 1045 1046 static bool labels_nonzero(const struct ovs_key_ct_labels *labels) 1047 { 1048 size_t i; 1049 1050 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++) 1051 if (labels->ct_labels_32[i]) 1052 return true; 1053 1054 return false; 1055 } 1056 1057 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1058 static struct hlist_head *ct_limit_hash_bucket( 1059 const struct ovs_ct_limit_info *info, u16 zone) 1060 { 1061 return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)]; 1062 } 1063 1064 /* Call with ovs_mutex */ 1065 static void ct_limit_set(const struct ovs_ct_limit_info *info, 1066 struct ovs_ct_limit *new_ct_limit) 1067 { 1068 struct ovs_ct_limit *ct_limit; 1069 struct hlist_head *head; 1070 1071 head = ct_limit_hash_bucket(info, new_ct_limit->zone); 1072 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1073 if (ct_limit->zone == new_ct_limit->zone) { 1074 hlist_replace_rcu(&ct_limit->hlist_node, 1075 &new_ct_limit->hlist_node); 1076 kfree_rcu(ct_limit, rcu); 1077 return; 1078 } 1079 } 1080 1081 hlist_add_head_rcu(&new_ct_limit->hlist_node, head); 1082 } 1083 1084 /* Call with ovs_mutex */ 1085 static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone) 1086 { 1087 struct ovs_ct_limit *ct_limit; 1088 struct hlist_head *head; 1089 struct hlist_node *n; 1090 1091 head = ct_limit_hash_bucket(info, zone); 1092 hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) { 1093 if (ct_limit->zone == zone) { 1094 hlist_del_rcu(&ct_limit->hlist_node); 1095 kfree_rcu(ct_limit, rcu); 1096 return; 1097 } 1098 } 1099 } 1100 1101 /* Call with RCU read lock */ 1102 static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone) 1103 { 1104 struct ovs_ct_limit *ct_limit; 1105 struct hlist_head *head; 1106 1107 head = ct_limit_hash_bucket(info, zone); 1108 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 1109 if (ct_limit->zone == zone) 1110 return ct_limit->limit; 1111 } 1112 1113 return info->default_limit; 1114 } 1115 1116 static int ovs_ct_check_limit(struct net *net, 1117 const struct ovs_conntrack_info *info, 1118 const struct nf_conntrack_tuple *tuple) 1119 { 1120 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1121 const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 1122 u32 per_zone_limit, connections; 1123 u32 conncount_key; 1124 1125 conncount_key = info->zone.id; 1126 1127 per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id); 1128 if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED) 1129 return 0; 1130 1131 connections = nf_conncount_count(net, ct_limit_info->data, 1132 &conncount_key, tuple, &info->zone); 1133 if (connections > per_zone_limit) 1134 return -ENOMEM; 1135 1136 return 0; 1137 } 1138 #endif 1139 1140 /* Lookup connection and confirm if unconfirmed. */ 1141 static int ovs_ct_commit(struct net *net, struct sw_flow_key *key, 1142 const struct ovs_conntrack_info *info, 1143 struct sk_buff *skb) 1144 { 1145 enum ip_conntrack_info ctinfo; 1146 struct nf_conn *ct; 1147 int err; 1148 1149 err = __ovs_ct_lookup(net, key, info, skb); 1150 if (err) 1151 return err; 1152 1153 /* The connection could be invalid, in which case this is a no-op.*/ 1154 ct = nf_ct_get(skb, &ctinfo); 1155 if (!ct) 1156 return 0; 1157 1158 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1159 if (static_branch_unlikely(&ovs_ct_limit_enabled)) { 1160 if (!nf_ct_is_confirmed(ct)) { 1161 err = ovs_ct_check_limit(net, info, 1162 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple); 1163 if (err) { 1164 net_warn_ratelimited("openvswitch: zone: %u " 1165 "execeeds conntrack limit\n", 1166 info->zone.id); 1167 return err; 1168 } 1169 } 1170 } 1171 #endif 1172 1173 /* Set the conntrack event mask if given. NEW and DELETE events have 1174 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener 1175 * typically would receive many kinds of updates. Setting the event 1176 * mask allows those events to be filtered. The set event mask will 1177 * remain in effect for the lifetime of the connection unless changed 1178 * by a further CT action with both the commit flag and the eventmask 1179 * option. */ 1180 if (info->have_eventmask) { 1181 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct); 1182 1183 if (cache) 1184 cache->ctmask = info->eventmask; 1185 } 1186 1187 /* Apply changes before confirming the connection so that the initial 1188 * conntrack NEW netlink event carries the values given in the CT 1189 * action. 1190 */ 1191 if (info->mark.mask) { 1192 err = ovs_ct_set_mark(ct, key, info->mark.value, 1193 info->mark.mask); 1194 if (err) 1195 return err; 1196 } 1197 if (!nf_ct_is_confirmed(ct)) { 1198 err = ovs_ct_init_labels(ct, key, &info->labels.value, 1199 &info->labels.mask); 1200 if (err) 1201 return err; 1202 } else if (labels_nonzero(&info->labels.mask)) { 1203 err = ovs_ct_set_labels(ct, key, &info->labels.value, 1204 &info->labels.mask); 1205 if (err) 1206 return err; 1207 } 1208 /* This will take care of sending queued events even if the connection 1209 * is already confirmed. 1210 */ 1211 if (nf_conntrack_confirm(skb) != NF_ACCEPT) 1212 return -EINVAL; 1213 1214 return 0; 1215 } 1216 1217 /* Trim the skb to the length specified by the IP/IPv6 header, 1218 * removing any trailing lower-layer padding. This prepares the skb 1219 * for higher-layer processing that assumes skb->len excludes padding 1220 * (such as nf_ip_checksum). The caller needs to pull the skb to the 1221 * network header, and ensure ip_hdr/ipv6_hdr points to valid data. 1222 */ 1223 static int ovs_skb_network_trim(struct sk_buff *skb) 1224 { 1225 unsigned int len; 1226 int err; 1227 1228 switch (skb->protocol) { 1229 case htons(ETH_P_IP): 1230 len = ntohs(ip_hdr(skb)->tot_len); 1231 break; 1232 case htons(ETH_P_IPV6): 1233 len = sizeof(struct ipv6hdr) 1234 + ntohs(ipv6_hdr(skb)->payload_len); 1235 break; 1236 default: 1237 len = skb->len; 1238 } 1239 1240 err = pskb_trim_rcsum(skb, len); 1241 if (err) 1242 kfree_skb(skb); 1243 1244 return err; 1245 } 1246 1247 /* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero 1248 * value if 'skb' is freed. 1249 */ 1250 int ovs_ct_execute(struct net *net, struct sk_buff *skb, 1251 struct sw_flow_key *key, 1252 const struct ovs_conntrack_info *info) 1253 { 1254 int nh_ofs; 1255 int err; 1256 1257 /* The conntrack module expects to be working at L3. */ 1258 nh_ofs = skb_network_offset(skb); 1259 skb_pull_rcsum(skb, nh_ofs); 1260 1261 err = ovs_skb_network_trim(skb); 1262 if (err) 1263 return err; 1264 1265 if (key->ip.frag != OVS_FRAG_TYPE_NONE) { 1266 err = handle_fragments(net, key, info->zone.id, skb); 1267 if (err) 1268 return err; 1269 } 1270 1271 if (info->commit) 1272 err = ovs_ct_commit(net, key, info, skb); 1273 else 1274 err = ovs_ct_lookup(net, key, info, skb); 1275 1276 skb_push(skb, nh_ofs); 1277 skb_postpush_rcsum(skb, skb->data, nh_ofs); 1278 if (err) 1279 kfree_skb(skb); 1280 return err; 1281 } 1282 1283 int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key) 1284 { 1285 if (skb_nfct(skb)) { 1286 nf_conntrack_put(skb_nfct(skb)); 1287 nf_ct_set(skb, NULL, IP_CT_UNTRACKED); 1288 ovs_ct_fill_key(skb, key); 1289 } 1290 1291 return 0; 1292 } 1293 1294 static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name, 1295 const struct sw_flow_key *key, bool log) 1296 { 1297 struct nf_conntrack_helper *helper; 1298 struct nf_conn_help *help; 1299 1300 helper = nf_conntrack_helper_try_module_get(name, info->family, 1301 key->ip.proto); 1302 if (!helper) { 1303 OVS_NLERR(log, "Unknown helper \"%s\"", name); 1304 return -EINVAL; 1305 } 1306 1307 help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL); 1308 if (!help) { 1309 nf_conntrack_helper_put(helper); 1310 return -ENOMEM; 1311 } 1312 1313 rcu_assign_pointer(help->helper, helper); 1314 info->helper = helper; 1315 return 0; 1316 } 1317 1318 #ifdef CONFIG_NF_NAT_NEEDED 1319 static int parse_nat(const struct nlattr *attr, 1320 struct ovs_conntrack_info *info, bool log) 1321 { 1322 struct nlattr *a; 1323 int rem; 1324 bool have_ip_max = false; 1325 bool have_proto_max = false; 1326 bool ip_vers = (info->family == NFPROTO_IPV6); 1327 1328 nla_for_each_nested(a, attr, rem) { 1329 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = { 1330 [OVS_NAT_ATTR_SRC] = {0, 0}, 1331 [OVS_NAT_ATTR_DST] = {0, 0}, 1332 [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr), 1333 sizeof(struct in6_addr)}, 1334 [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr), 1335 sizeof(struct in6_addr)}, 1336 [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)}, 1337 [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)}, 1338 [OVS_NAT_ATTR_PERSISTENT] = {0, 0}, 1339 [OVS_NAT_ATTR_PROTO_HASH] = {0, 0}, 1340 [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0}, 1341 }; 1342 int type = nla_type(a); 1343 1344 if (type > OVS_NAT_ATTR_MAX) { 1345 OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)", 1346 type, OVS_NAT_ATTR_MAX); 1347 return -EINVAL; 1348 } 1349 1350 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) { 1351 OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)", 1352 type, nla_len(a), 1353 ovs_nat_attr_lens[type][ip_vers]); 1354 return -EINVAL; 1355 } 1356 1357 switch (type) { 1358 case OVS_NAT_ATTR_SRC: 1359 case OVS_NAT_ATTR_DST: 1360 if (info->nat) { 1361 OVS_NLERR(log, "Only one type of NAT may be specified"); 1362 return -ERANGE; 1363 } 1364 info->nat |= OVS_CT_NAT; 1365 info->nat |= ((type == OVS_NAT_ATTR_SRC) 1366 ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT); 1367 break; 1368 1369 case OVS_NAT_ATTR_IP_MIN: 1370 nla_memcpy(&info->range.min_addr, a, 1371 sizeof(info->range.min_addr)); 1372 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1373 break; 1374 1375 case OVS_NAT_ATTR_IP_MAX: 1376 have_ip_max = true; 1377 nla_memcpy(&info->range.max_addr, a, 1378 sizeof(info->range.max_addr)); 1379 info->range.flags |= NF_NAT_RANGE_MAP_IPS; 1380 break; 1381 1382 case OVS_NAT_ATTR_PROTO_MIN: 1383 info->range.min_proto.all = htons(nla_get_u16(a)); 1384 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1385 break; 1386 1387 case OVS_NAT_ATTR_PROTO_MAX: 1388 have_proto_max = true; 1389 info->range.max_proto.all = htons(nla_get_u16(a)); 1390 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; 1391 break; 1392 1393 case OVS_NAT_ATTR_PERSISTENT: 1394 info->range.flags |= NF_NAT_RANGE_PERSISTENT; 1395 break; 1396 1397 case OVS_NAT_ATTR_PROTO_HASH: 1398 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM; 1399 break; 1400 1401 case OVS_NAT_ATTR_PROTO_RANDOM: 1402 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY; 1403 break; 1404 1405 default: 1406 OVS_NLERR(log, "Unknown nat attribute (%d)", type); 1407 return -EINVAL; 1408 } 1409 } 1410 1411 if (rem > 0) { 1412 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem); 1413 return -EINVAL; 1414 } 1415 if (!info->nat) { 1416 /* Do not allow flags if no type is given. */ 1417 if (info->range.flags) { 1418 OVS_NLERR(log, 1419 "NAT flags may be given only when NAT range (SRC or DST) is also specified." 1420 ); 1421 return -EINVAL; 1422 } 1423 info->nat = OVS_CT_NAT; /* NAT existing connections. */ 1424 } else if (!info->commit) { 1425 OVS_NLERR(log, 1426 "NAT attributes may be specified only when CT COMMIT flag is also specified." 1427 ); 1428 return -EINVAL; 1429 } 1430 /* Allow missing IP_MAX. */ 1431 if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) { 1432 memcpy(&info->range.max_addr, &info->range.min_addr, 1433 sizeof(info->range.max_addr)); 1434 } 1435 /* Allow missing PROTO_MAX. */ 1436 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1437 !have_proto_max) { 1438 info->range.max_proto.all = info->range.min_proto.all; 1439 } 1440 return 0; 1441 } 1442 #endif 1443 1444 static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = { 1445 [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1446 [OVS_CT_ATTR_FORCE_COMMIT] = { .minlen = 0, .maxlen = 0 }, 1447 [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16), 1448 .maxlen = sizeof(u16) }, 1449 [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark), 1450 .maxlen = sizeof(struct md_mark) }, 1451 [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels), 1452 .maxlen = sizeof(struct md_labels) }, 1453 [OVS_CT_ATTR_HELPER] = { .minlen = 1, 1454 .maxlen = NF_CT_HELPER_NAME_LEN }, 1455 #ifdef CONFIG_NF_NAT_NEEDED 1456 /* NAT length is checked when parsing the nested attributes. */ 1457 [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX }, 1458 #endif 1459 [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32), 1460 .maxlen = sizeof(u32) }, 1461 }; 1462 1463 static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info, 1464 const char **helper, bool log) 1465 { 1466 struct nlattr *a; 1467 int rem; 1468 1469 nla_for_each_nested(a, attr, rem) { 1470 int type = nla_type(a); 1471 int maxlen; 1472 int minlen; 1473 1474 if (type > OVS_CT_ATTR_MAX) { 1475 OVS_NLERR(log, 1476 "Unknown conntrack attr (type=%d, max=%d)", 1477 type, OVS_CT_ATTR_MAX); 1478 return -EINVAL; 1479 } 1480 1481 maxlen = ovs_ct_attr_lens[type].maxlen; 1482 minlen = ovs_ct_attr_lens[type].minlen; 1483 if (nla_len(a) < minlen || nla_len(a) > maxlen) { 1484 OVS_NLERR(log, 1485 "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)", 1486 type, nla_len(a), maxlen); 1487 return -EINVAL; 1488 } 1489 1490 switch (type) { 1491 case OVS_CT_ATTR_FORCE_COMMIT: 1492 info->force = true; 1493 /* fall through. */ 1494 case OVS_CT_ATTR_COMMIT: 1495 info->commit = true; 1496 break; 1497 #ifdef CONFIG_NF_CONNTRACK_ZONES 1498 case OVS_CT_ATTR_ZONE: 1499 info->zone.id = nla_get_u16(a); 1500 break; 1501 #endif 1502 #ifdef CONFIG_NF_CONNTRACK_MARK 1503 case OVS_CT_ATTR_MARK: { 1504 struct md_mark *mark = nla_data(a); 1505 1506 if (!mark->mask) { 1507 OVS_NLERR(log, "ct_mark mask cannot be 0"); 1508 return -EINVAL; 1509 } 1510 info->mark = *mark; 1511 break; 1512 } 1513 #endif 1514 #ifdef CONFIG_NF_CONNTRACK_LABELS 1515 case OVS_CT_ATTR_LABELS: { 1516 struct md_labels *labels = nla_data(a); 1517 1518 if (!labels_nonzero(&labels->mask)) { 1519 OVS_NLERR(log, "ct_labels mask cannot be 0"); 1520 return -EINVAL; 1521 } 1522 info->labels = *labels; 1523 break; 1524 } 1525 #endif 1526 case OVS_CT_ATTR_HELPER: 1527 *helper = nla_data(a); 1528 if (!memchr(*helper, '\0', nla_len(a))) { 1529 OVS_NLERR(log, "Invalid conntrack helper"); 1530 return -EINVAL; 1531 } 1532 break; 1533 #ifdef CONFIG_NF_NAT_NEEDED 1534 case OVS_CT_ATTR_NAT: { 1535 int err = parse_nat(a, info, log); 1536 1537 if (err) 1538 return err; 1539 break; 1540 } 1541 #endif 1542 case OVS_CT_ATTR_EVENTMASK: 1543 info->have_eventmask = true; 1544 info->eventmask = nla_get_u32(a); 1545 break; 1546 1547 default: 1548 OVS_NLERR(log, "Unknown conntrack attr (%d)", 1549 type); 1550 return -EINVAL; 1551 } 1552 } 1553 1554 #ifdef CONFIG_NF_CONNTRACK_MARK 1555 if (!info->commit && info->mark.mask) { 1556 OVS_NLERR(log, 1557 "Setting conntrack mark requires 'commit' flag."); 1558 return -EINVAL; 1559 } 1560 #endif 1561 #ifdef CONFIG_NF_CONNTRACK_LABELS 1562 if (!info->commit && labels_nonzero(&info->labels.mask)) { 1563 OVS_NLERR(log, 1564 "Setting conntrack labels requires 'commit' flag."); 1565 return -EINVAL; 1566 } 1567 #endif 1568 if (rem > 0) { 1569 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem); 1570 return -EINVAL; 1571 } 1572 1573 return 0; 1574 } 1575 1576 bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr) 1577 { 1578 if (attr == OVS_KEY_ATTR_CT_STATE) 1579 return true; 1580 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1581 attr == OVS_KEY_ATTR_CT_ZONE) 1582 return true; 1583 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && 1584 attr == OVS_KEY_ATTR_CT_MARK) 1585 return true; 1586 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1587 attr == OVS_KEY_ATTR_CT_LABELS) { 1588 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 1589 1590 return ovs_net->xt_label; 1591 } 1592 1593 return false; 1594 } 1595 1596 int ovs_ct_copy_action(struct net *net, const struct nlattr *attr, 1597 const struct sw_flow_key *key, 1598 struct sw_flow_actions **sfa, bool log) 1599 { 1600 struct ovs_conntrack_info ct_info; 1601 const char *helper = NULL; 1602 u16 family; 1603 int err; 1604 1605 family = key_to_nfproto(key); 1606 if (family == NFPROTO_UNSPEC) { 1607 OVS_NLERR(log, "ct family unspecified"); 1608 return -EINVAL; 1609 } 1610 1611 memset(&ct_info, 0, sizeof(ct_info)); 1612 ct_info.family = family; 1613 1614 nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID, 1615 NF_CT_DEFAULT_ZONE_DIR, 0); 1616 1617 err = parse_ct(attr, &ct_info, &helper, log); 1618 if (err) 1619 return err; 1620 1621 /* Set up template for tracking connections in specific zones. */ 1622 ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL); 1623 if (!ct_info.ct) { 1624 OVS_NLERR(log, "Failed to allocate conntrack template"); 1625 return -ENOMEM; 1626 } 1627 1628 __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status); 1629 nf_conntrack_get(&ct_info.ct->ct_general); 1630 1631 if (helper) { 1632 err = ovs_ct_add_helper(&ct_info, helper, key, log); 1633 if (err) 1634 goto err_free_ct; 1635 } 1636 1637 err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info, 1638 sizeof(ct_info), log); 1639 if (err) 1640 goto err_free_ct; 1641 1642 return 0; 1643 err_free_ct: 1644 __ovs_ct_free_action(&ct_info); 1645 return err; 1646 } 1647 1648 #ifdef CONFIG_NF_NAT_NEEDED 1649 static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info, 1650 struct sk_buff *skb) 1651 { 1652 struct nlattr *start; 1653 1654 start = nla_nest_start(skb, OVS_CT_ATTR_NAT); 1655 if (!start) 1656 return false; 1657 1658 if (info->nat & OVS_CT_SRC_NAT) { 1659 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC)) 1660 return false; 1661 } else if (info->nat & OVS_CT_DST_NAT) { 1662 if (nla_put_flag(skb, OVS_NAT_ATTR_DST)) 1663 return false; 1664 } else { 1665 goto out; 1666 } 1667 1668 if (info->range.flags & NF_NAT_RANGE_MAP_IPS) { 1669 if (IS_ENABLED(CONFIG_NF_NAT_IPV4) && 1670 info->family == NFPROTO_IPV4) { 1671 if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN, 1672 info->range.min_addr.ip) || 1673 (info->range.max_addr.ip 1674 != info->range.min_addr.ip && 1675 (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX, 1676 info->range.max_addr.ip)))) 1677 return false; 1678 } else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) && 1679 info->family == NFPROTO_IPV6) { 1680 if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN, 1681 &info->range.min_addr.in6) || 1682 (memcmp(&info->range.max_addr.in6, 1683 &info->range.min_addr.in6, 1684 sizeof(info->range.max_addr.in6)) && 1685 (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX, 1686 &info->range.max_addr.in6)))) 1687 return false; 1688 } else { 1689 return false; 1690 } 1691 } 1692 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED && 1693 (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN, 1694 ntohs(info->range.min_proto.all)) || 1695 (info->range.max_proto.all != info->range.min_proto.all && 1696 nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX, 1697 ntohs(info->range.max_proto.all))))) 1698 return false; 1699 1700 if (info->range.flags & NF_NAT_RANGE_PERSISTENT && 1701 nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT)) 1702 return false; 1703 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM && 1704 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH)) 1705 return false; 1706 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY && 1707 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM)) 1708 return false; 1709 out: 1710 nla_nest_end(skb, start); 1711 1712 return true; 1713 } 1714 #endif 1715 1716 int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info, 1717 struct sk_buff *skb) 1718 { 1719 struct nlattr *start; 1720 1721 start = nla_nest_start(skb, OVS_ACTION_ATTR_CT); 1722 if (!start) 1723 return -EMSGSIZE; 1724 1725 if (ct_info->commit && nla_put_flag(skb, ct_info->force 1726 ? OVS_CT_ATTR_FORCE_COMMIT 1727 : OVS_CT_ATTR_COMMIT)) 1728 return -EMSGSIZE; 1729 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) && 1730 nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id)) 1731 return -EMSGSIZE; 1732 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask && 1733 nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark), 1734 &ct_info->mark)) 1735 return -EMSGSIZE; 1736 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) && 1737 labels_nonzero(&ct_info->labels.mask) && 1738 nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels), 1739 &ct_info->labels)) 1740 return -EMSGSIZE; 1741 if (ct_info->helper) { 1742 if (nla_put_string(skb, OVS_CT_ATTR_HELPER, 1743 ct_info->helper->name)) 1744 return -EMSGSIZE; 1745 } 1746 if (ct_info->have_eventmask && 1747 nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask)) 1748 return -EMSGSIZE; 1749 1750 #ifdef CONFIG_NF_NAT_NEEDED 1751 if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb)) 1752 return -EMSGSIZE; 1753 #endif 1754 nla_nest_end(skb, start); 1755 1756 return 0; 1757 } 1758 1759 void ovs_ct_free_action(const struct nlattr *a) 1760 { 1761 struct ovs_conntrack_info *ct_info = nla_data(a); 1762 1763 __ovs_ct_free_action(ct_info); 1764 } 1765 1766 static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info) 1767 { 1768 if (ct_info->helper) 1769 nf_conntrack_helper_put(ct_info->helper); 1770 if (ct_info->ct) 1771 nf_ct_tmpl_free(ct_info->ct); 1772 } 1773 1774 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 1775 static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net) 1776 { 1777 int i, err; 1778 1779 ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info), 1780 GFP_KERNEL); 1781 if (!ovs_net->ct_limit_info) 1782 return -ENOMEM; 1783 1784 ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT; 1785 ovs_net->ct_limit_info->limits = 1786 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head), 1787 GFP_KERNEL); 1788 if (!ovs_net->ct_limit_info->limits) { 1789 kfree(ovs_net->ct_limit_info); 1790 return -ENOMEM; 1791 } 1792 1793 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++) 1794 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]); 1795 1796 ovs_net->ct_limit_info->data = 1797 nf_conncount_init(net, NFPROTO_INET, sizeof(u32)); 1798 1799 if (IS_ERR(ovs_net->ct_limit_info->data)) { 1800 err = PTR_ERR(ovs_net->ct_limit_info->data); 1801 kfree(ovs_net->ct_limit_info->limits); 1802 kfree(ovs_net->ct_limit_info); 1803 pr_err("openvswitch: failed to init nf_conncount %d\n", err); 1804 return err; 1805 } 1806 return 0; 1807 } 1808 1809 static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net) 1810 { 1811 const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info; 1812 int i; 1813 1814 nf_conncount_destroy(net, NFPROTO_INET, info->data); 1815 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 1816 struct hlist_head *head = &info->limits[i]; 1817 struct ovs_ct_limit *ct_limit; 1818 1819 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) 1820 kfree_rcu(ct_limit, rcu); 1821 } 1822 kfree(ovs_net->ct_limit_info->limits); 1823 kfree(ovs_net->ct_limit_info); 1824 } 1825 1826 static struct sk_buff * 1827 ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd, 1828 struct ovs_header **ovs_reply_header) 1829 { 1830 struct ovs_header *ovs_header = info->userhdr; 1831 struct sk_buff *skb; 1832 1833 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); 1834 if (!skb) 1835 return ERR_PTR(-ENOMEM); 1836 1837 *ovs_reply_header = genlmsg_put(skb, info->snd_portid, 1838 info->snd_seq, 1839 &dp_ct_limit_genl_family, 0, cmd); 1840 1841 if (!*ovs_reply_header) { 1842 nlmsg_free(skb); 1843 return ERR_PTR(-EMSGSIZE); 1844 } 1845 (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex; 1846 1847 return skb; 1848 } 1849 1850 static bool check_zone_id(int zone_id, u16 *pzone) 1851 { 1852 if (zone_id >= 0 && zone_id <= 65535) { 1853 *pzone = (u16)zone_id; 1854 return true; 1855 } 1856 return false; 1857 } 1858 1859 static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit, 1860 struct ovs_ct_limit_info *info) 1861 { 1862 struct ovs_zone_limit *zone_limit; 1863 int rem; 1864 u16 zone; 1865 1866 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1867 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1868 1869 while (rem >= sizeof(*zone_limit)) { 1870 if (unlikely(zone_limit->zone_id == 1871 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1872 ovs_lock(); 1873 info->default_limit = zone_limit->limit; 1874 ovs_unlock(); 1875 } else if (unlikely(!check_zone_id( 1876 zone_limit->zone_id, &zone))) { 1877 OVS_NLERR(true, "zone id is out of range"); 1878 } else { 1879 struct ovs_ct_limit *ct_limit; 1880 1881 ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL); 1882 if (!ct_limit) 1883 return -ENOMEM; 1884 1885 ct_limit->zone = zone; 1886 ct_limit->limit = zone_limit->limit; 1887 1888 ovs_lock(); 1889 ct_limit_set(info, ct_limit); 1890 ovs_unlock(); 1891 } 1892 rem -= NLA_ALIGN(sizeof(*zone_limit)); 1893 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 1894 NLA_ALIGN(sizeof(*zone_limit))); 1895 } 1896 1897 if (rem) 1898 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem); 1899 1900 return 0; 1901 } 1902 1903 static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit, 1904 struct ovs_ct_limit_info *info) 1905 { 1906 struct ovs_zone_limit *zone_limit; 1907 int rem; 1908 u16 zone; 1909 1910 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1911 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1912 1913 while (rem >= sizeof(*zone_limit)) { 1914 if (unlikely(zone_limit->zone_id == 1915 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1916 ovs_lock(); 1917 info->default_limit = OVS_CT_LIMIT_DEFAULT; 1918 ovs_unlock(); 1919 } else if (unlikely(!check_zone_id( 1920 zone_limit->zone_id, &zone))) { 1921 OVS_NLERR(true, "zone id is out of range"); 1922 } else { 1923 ovs_lock(); 1924 ct_limit_del(info, zone); 1925 ovs_unlock(); 1926 } 1927 rem -= NLA_ALIGN(sizeof(*zone_limit)); 1928 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 1929 NLA_ALIGN(sizeof(*zone_limit))); 1930 } 1931 1932 if (rem) 1933 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem); 1934 1935 return 0; 1936 } 1937 1938 static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info, 1939 struct sk_buff *reply) 1940 { 1941 struct ovs_zone_limit zone_limit; 1942 int err; 1943 1944 zone_limit.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE; 1945 zone_limit.limit = info->default_limit; 1946 err = nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 1947 if (err) 1948 return err; 1949 1950 return 0; 1951 } 1952 1953 static int __ovs_ct_limit_get_zone_limit(struct net *net, 1954 struct nf_conncount_data *data, 1955 u16 zone_id, u32 limit, 1956 struct sk_buff *reply) 1957 { 1958 struct nf_conntrack_zone ct_zone; 1959 struct ovs_zone_limit zone_limit; 1960 u32 conncount_key = zone_id; 1961 1962 zone_limit.zone_id = zone_id; 1963 zone_limit.limit = limit; 1964 nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0); 1965 1966 zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL, 1967 &ct_zone); 1968 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit); 1969 } 1970 1971 static int ovs_ct_limit_get_zone_limit(struct net *net, 1972 struct nlattr *nla_zone_limit, 1973 struct ovs_ct_limit_info *info, 1974 struct sk_buff *reply) 1975 { 1976 struct ovs_zone_limit *zone_limit; 1977 int rem, err; 1978 u32 limit; 1979 u16 zone; 1980 1981 rem = NLA_ALIGN(nla_len(nla_zone_limit)); 1982 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit); 1983 1984 while (rem >= sizeof(*zone_limit)) { 1985 if (unlikely(zone_limit->zone_id == 1986 OVS_ZONE_LIMIT_DEFAULT_ZONE)) { 1987 err = ovs_ct_limit_get_default_limit(info, reply); 1988 if (err) 1989 return err; 1990 } else if (unlikely(!check_zone_id(zone_limit->zone_id, 1991 &zone))) { 1992 OVS_NLERR(true, "zone id is out of range"); 1993 } else { 1994 rcu_read_lock(); 1995 limit = ct_limit_get(info, zone); 1996 rcu_read_unlock(); 1997 1998 err = __ovs_ct_limit_get_zone_limit( 1999 net, info->data, zone, limit, reply); 2000 if (err) 2001 return err; 2002 } 2003 rem -= NLA_ALIGN(sizeof(*zone_limit)); 2004 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit + 2005 NLA_ALIGN(sizeof(*zone_limit))); 2006 } 2007 2008 if (rem) 2009 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem); 2010 2011 return 0; 2012 } 2013 2014 static int ovs_ct_limit_get_all_zone_limit(struct net *net, 2015 struct ovs_ct_limit_info *info, 2016 struct sk_buff *reply) 2017 { 2018 struct ovs_ct_limit *ct_limit; 2019 struct hlist_head *head; 2020 int i, err = 0; 2021 2022 err = ovs_ct_limit_get_default_limit(info, reply); 2023 if (err) 2024 return err; 2025 2026 rcu_read_lock(); 2027 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) { 2028 head = &info->limits[i]; 2029 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) { 2030 err = __ovs_ct_limit_get_zone_limit(net, info->data, 2031 ct_limit->zone, ct_limit->limit, reply); 2032 if (err) 2033 goto exit_err; 2034 } 2035 } 2036 2037 exit_err: 2038 rcu_read_unlock(); 2039 return err; 2040 } 2041 2042 static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info) 2043 { 2044 struct nlattr **a = info->attrs; 2045 struct sk_buff *reply; 2046 struct ovs_header *ovs_reply_header; 2047 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2048 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2049 int err; 2050 2051 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET, 2052 &ovs_reply_header); 2053 if (IS_ERR(reply)) 2054 return PTR_ERR(reply); 2055 2056 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2057 err = -EINVAL; 2058 goto exit_err; 2059 } 2060 2061 err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2062 ct_limit_info); 2063 if (err) 2064 goto exit_err; 2065 2066 static_branch_enable(&ovs_ct_limit_enabled); 2067 2068 genlmsg_end(reply, ovs_reply_header); 2069 return genlmsg_reply(reply, info); 2070 2071 exit_err: 2072 nlmsg_free(reply); 2073 return err; 2074 } 2075 2076 static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info) 2077 { 2078 struct nlattr **a = info->attrs; 2079 struct sk_buff *reply; 2080 struct ovs_header *ovs_reply_header; 2081 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id); 2082 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2083 int err; 2084 2085 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL, 2086 &ovs_reply_header); 2087 if (IS_ERR(reply)) 2088 return PTR_ERR(reply); 2089 2090 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2091 err = -EINVAL; 2092 goto exit_err; 2093 } 2094 2095 err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], 2096 ct_limit_info); 2097 if (err) 2098 goto exit_err; 2099 2100 genlmsg_end(reply, ovs_reply_header); 2101 return genlmsg_reply(reply, info); 2102 2103 exit_err: 2104 nlmsg_free(reply); 2105 return err; 2106 } 2107 2108 static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info) 2109 { 2110 struct nlattr **a = info->attrs; 2111 struct nlattr *nla_reply; 2112 struct sk_buff *reply; 2113 struct ovs_header *ovs_reply_header; 2114 struct net *net = sock_net(skb->sk); 2115 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2116 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info; 2117 int err; 2118 2119 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET, 2120 &ovs_reply_header); 2121 if (IS_ERR(reply)) 2122 return PTR_ERR(reply); 2123 2124 nla_reply = nla_nest_start(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT); 2125 2126 if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) { 2127 err = ovs_ct_limit_get_zone_limit( 2128 net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info, 2129 reply); 2130 if (err) 2131 goto exit_err; 2132 } else { 2133 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info, 2134 reply); 2135 if (err) 2136 goto exit_err; 2137 } 2138 2139 nla_nest_end(reply, nla_reply); 2140 genlmsg_end(reply, ovs_reply_header); 2141 return genlmsg_reply(reply, info); 2142 2143 exit_err: 2144 nlmsg_free(reply); 2145 return err; 2146 } 2147 2148 static struct genl_ops ct_limit_genl_ops[] = { 2149 { .cmd = OVS_CT_LIMIT_CMD_SET, 2150 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2151 * privilege. */ 2152 .policy = ct_limit_policy, 2153 .doit = ovs_ct_limit_cmd_set, 2154 }, 2155 { .cmd = OVS_CT_LIMIT_CMD_DEL, 2156 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN 2157 * privilege. */ 2158 .policy = ct_limit_policy, 2159 .doit = ovs_ct_limit_cmd_del, 2160 }, 2161 { .cmd = OVS_CT_LIMIT_CMD_GET, 2162 .flags = 0, /* OK for unprivileged users. */ 2163 .policy = ct_limit_policy, 2164 .doit = ovs_ct_limit_cmd_get, 2165 }, 2166 }; 2167 2168 static const struct genl_multicast_group ovs_ct_limit_multicast_group = { 2169 .name = OVS_CT_LIMIT_MCGROUP, 2170 }; 2171 2172 struct genl_family dp_ct_limit_genl_family __ro_after_init = { 2173 .hdrsize = sizeof(struct ovs_header), 2174 .name = OVS_CT_LIMIT_FAMILY, 2175 .version = OVS_CT_LIMIT_VERSION, 2176 .maxattr = OVS_CT_LIMIT_ATTR_MAX, 2177 .netnsok = true, 2178 .parallel_ops = true, 2179 .ops = ct_limit_genl_ops, 2180 .n_ops = ARRAY_SIZE(ct_limit_genl_ops), 2181 .mcgrps = &ovs_ct_limit_multicast_group, 2182 .n_mcgrps = 1, 2183 .module = THIS_MODULE, 2184 }; 2185 #endif 2186 2187 int ovs_ct_init(struct net *net) 2188 { 2189 unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE; 2190 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2191 2192 if (nf_connlabels_get(net, n_bits - 1)) { 2193 ovs_net->xt_label = false; 2194 OVS_NLERR(true, "Failed to set connlabel length"); 2195 } else { 2196 ovs_net->xt_label = true; 2197 } 2198 2199 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2200 return ovs_ct_limit_init(net, ovs_net); 2201 #else 2202 return 0; 2203 #endif 2204 } 2205 2206 void ovs_ct_exit(struct net *net) 2207 { 2208 struct ovs_net *ovs_net = net_generic(net, ovs_net_id); 2209 2210 #if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT) 2211 ovs_ct_limit_exit(net, ovs_net); 2212 #endif 2213 2214 if (ovs_net->xt_label) 2215 nf_connlabels_put(net); 2216 } 2217