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