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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 <net/ip.h>
20#include <net/netfilter/nf_conntrack_core.h>
21#include <net/netfilter/nf_conntrack_helper.h>
22#include <net/netfilter/nf_conntrack_labels.h>
23#include <net/netfilter/nf_conntrack_seqadj.h>
24#include <net/netfilter/nf_conntrack_zones.h>
25#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
26
27#ifdef CONFIG_NF_NAT_NEEDED
28#include <linux/netfilter/nf_nat.h>
29#include <net/netfilter/nf_nat_core.h>
30#include <net/netfilter/nf_nat_l3proto.h>
31#endif
32
33#include "datapath.h"
34#include "conntrack.h"
35#include "flow.h"
36#include "flow_netlink.h"
37
38struct ovs_ct_len_tbl {
39 int maxlen;
40 int minlen;
41};
42
43/* Metadata mark for masked write to conntrack mark */
44struct md_mark {
45 u32 value;
46 u32 mask;
47};
48
49/* Metadata label for masked write to conntrack label. */
50struct md_labels {
51 struct ovs_key_ct_labels value;
52 struct ovs_key_ct_labels mask;
53};
54
55enum ovs_ct_nat {
56 OVS_CT_NAT = 1 << 0, /* NAT for committed connections only. */
57 OVS_CT_SRC_NAT = 1 << 1, /* Source NAT for NEW connections. */
58 OVS_CT_DST_NAT = 1 << 2, /* Destination NAT for NEW connections. */
59};
60
61/* Conntrack action context for execution. */
62struct ovs_conntrack_info {
63 struct nf_conntrack_helper *helper;
64 struct nf_conntrack_zone zone;
65 struct nf_conn *ct;
66 u8 commit : 1;
67 u8 nat : 3; /* enum ovs_ct_nat */
68 u16 family;
69 struct md_mark mark;
70 struct md_labels labels;
71#ifdef CONFIG_NF_NAT_NEEDED
72 struct nf_nat_range range; /* Only present for SRC NAT and DST NAT. */
73#endif
74};
75
76static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);
77
78static u16 key_to_nfproto(const struct sw_flow_key *key)
79{
80 switch (ntohs(key->eth.type)) {
81 case ETH_P_IP:
82 return NFPROTO_IPV4;
83 case ETH_P_IPV6:
84 return NFPROTO_IPV6;
85 default:
86 return NFPROTO_UNSPEC;
87 }
88}
89
90/* Map SKB connection state into the values used by flow definition. */
91static u8 ovs_ct_get_state(enum ip_conntrack_info ctinfo)
92{
93 u8 ct_state = OVS_CS_F_TRACKED;
94
95 switch (ctinfo) {
96 case IP_CT_ESTABLISHED_REPLY:
97 case IP_CT_RELATED_REPLY:
98 ct_state |= OVS_CS_F_REPLY_DIR;
99 break;
100 default:
101 break;
102 }
103
104 switch (ctinfo) {
105 case IP_CT_ESTABLISHED:
106 case IP_CT_ESTABLISHED_REPLY:
107 ct_state |= OVS_CS_F_ESTABLISHED;
108 break;
109 case IP_CT_RELATED:
110 case IP_CT_RELATED_REPLY:
111 ct_state |= OVS_CS_F_RELATED;
112 break;
113 case IP_CT_NEW:
114 ct_state |= OVS_CS_F_NEW;
115 break;
116 default:
117 break;
118 }
119
120 return ct_state;
121}
122
123static u32 ovs_ct_get_mark(const struct nf_conn *ct)
124{
125#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
126 return ct ? ct->mark : 0;
127#else
128 return 0;
129#endif
130}
131
132static void ovs_ct_get_labels(const struct nf_conn *ct,
133 struct ovs_key_ct_labels *labels)
134{
135 struct nf_conn_labels *cl = ct ? nf_ct_labels_find(ct) : NULL;
136
137 if (cl) {
138 size_t len = sizeof(cl->bits);
139
140 if (len > OVS_CT_LABELS_LEN)
141 len = OVS_CT_LABELS_LEN;
142 else if (len < OVS_CT_LABELS_LEN)
143 memset(labels, 0, OVS_CT_LABELS_LEN);
144 memcpy(labels, cl->bits, len);
145 } else {
146 memset(labels, 0, OVS_CT_LABELS_LEN);
147 }
148}
149
150static void __ovs_ct_update_key(struct sw_flow_key *key, u8 state,
151 const struct nf_conntrack_zone *zone,
152 const struct nf_conn *ct)
153{
154 key->ct.state = state;
155 key->ct.zone = zone->id;
156 key->ct.mark = ovs_ct_get_mark(ct);
157 ovs_ct_get_labels(ct, &key->ct.labels);
158}
159
160/* Update 'key' based on skb->nfct. If 'post_ct' is true, then OVS has
161 * previously sent the packet to conntrack via the ct action. If
162 * 'keep_nat_flags' is true, the existing NAT flags retained, else they are
163 * initialized from the connection status.
164 */
165static void ovs_ct_update_key(const struct sk_buff *skb,
166 const struct ovs_conntrack_info *info,
167 struct sw_flow_key *key, bool post_ct,
168 bool keep_nat_flags)
169{
170 const struct nf_conntrack_zone *zone = &nf_ct_zone_dflt;
171 enum ip_conntrack_info ctinfo;
172 struct nf_conn *ct;
173 u8 state = 0;
174
175 ct = nf_ct_get(skb, &ctinfo);
176 if (ct) {
177 state = ovs_ct_get_state(ctinfo);
178 /* All unconfirmed entries are NEW connections. */
179 if (!nf_ct_is_confirmed(ct))
180 state |= OVS_CS_F_NEW;
181 /* OVS persists the related flag for the duration of the
182 * connection.
183 */
184 if (ct->master)
185 state |= OVS_CS_F_RELATED;
186 if (keep_nat_flags) {
187 state |= key->ct.state & OVS_CS_F_NAT_MASK;
188 } else {
189 if (ct->status & IPS_SRC_NAT)
190 state |= OVS_CS_F_SRC_NAT;
191 if (ct->status & IPS_DST_NAT)
192 state |= OVS_CS_F_DST_NAT;
193 }
194 zone = nf_ct_zone(ct);
195 } else if (post_ct) {
196 state = OVS_CS_F_TRACKED | OVS_CS_F_INVALID;
197 if (info)
198 zone = &info->zone;
199 }
200 __ovs_ct_update_key(key, state, zone, ct);
201}
202
203/* This is called to initialize CT key fields possibly coming in from the local
204 * stack.
205 */
206void ovs_ct_fill_key(const struct sk_buff *skb, struct sw_flow_key *key)
207{
208 ovs_ct_update_key(skb, NULL, key, false, false);
209}
210
211int ovs_ct_put_key(const struct sw_flow_key *key, struct sk_buff *skb)
212{
213 if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, key->ct.state))
214 return -EMSGSIZE;
215
216 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
217 nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, key->ct.zone))
218 return -EMSGSIZE;
219
220 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
221 nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, key->ct.mark))
222 return -EMSGSIZE;
223
224 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
225 nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(key->ct.labels),
226 &key->ct.labels))
227 return -EMSGSIZE;
228
229 return 0;
230}
231
232static int ovs_ct_set_mark(struct sk_buff *skb, struct sw_flow_key *key,
233 u32 ct_mark, u32 mask)
234{
235#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
236 enum ip_conntrack_info ctinfo;
237 struct nf_conn *ct;
238 u32 new_mark;
239
240 /* The connection could be invalid, in which case set_mark is no-op. */
241 ct = nf_ct_get(skb, &ctinfo);
242 if (!ct)
243 return 0;
244
245 new_mark = ct_mark | (ct->mark & ~(mask));
246 if (ct->mark != new_mark) {
247 ct->mark = new_mark;
248 nf_conntrack_event_cache(IPCT_MARK, ct);
249 key->ct.mark = new_mark;
250 }
251
252 return 0;
253#else
254 return -ENOTSUPP;
255#endif
256}
257
258static int ovs_ct_set_labels(struct sk_buff *skb, struct sw_flow_key *key,
259 const struct ovs_key_ct_labels *labels,
260 const struct ovs_key_ct_labels *mask)
261{
262 enum ip_conntrack_info ctinfo;
263 struct nf_conn_labels *cl;
264 struct nf_conn *ct;
265 int err;
266
267 /* The connection could be invalid, in which case set_label is no-op.*/
268 ct = nf_ct_get(skb, &ctinfo);
269 if (!ct)
270 return 0;
271
272 cl = nf_ct_labels_find(ct);
273 if (!cl) {
274 nf_ct_labels_ext_add(ct);
275 cl = nf_ct_labels_find(ct);
276 }
277 if (!cl || sizeof(cl->bits) < OVS_CT_LABELS_LEN)
278 return -ENOSPC;
279
280 err = nf_connlabels_replace(ct, (u32 *)labels, (u32 *)mask,
281 OVS_CT_LABELS_LEN / sizeof(u32));
282 if (err)
283 return err;
284
285 ovs_ct_get_labels(ct, &key->ct.labels);
286 return 0;
287}
288
289/* 'skb' should already be pulled to nh_ofs. */
290static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
291{
292 const struct nf_conntrack_helper *helper;
293 const struct nf_conn_help *help;
294 enum ip_conntrack_info ctinfo;
295 unsigned int protoff;
296 struct nf_conn *ct;
297 int err;
298
299 ct = nf_ct_get(skb, &ctinfo);
300 if (!ct || ctinfo == IP_CT_RELATED_REPLY)
301 return NF_ACCEPT;
302
303 help = nfct_help(ct);
304 if (!help)
305 return NF_ACCEPT;
306
307 helper = rcu_dereference(help->helper);
308 if (!helper)
309 return NF_ACCEPT;
310
311 switch (proto) {
312 case NFPROTO_IPV4:
313 protoff = ip_hdrlen(skb);
314 break;
315 case NFPROTO_IPV6: {
316 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
317 __be16 frag_off;
318 int ofs;
319
320 ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
321 &frag_off);
322 if (ofs < 0 || (frag_off & htons(~0x7)) != 0) {
323 pr_debug("proto header not found\n");
324 return NF_ACCEPT;
325 }
326 protoff = ofs;
327 break;
328 }
329 default:
330 WARN_ONCE(1, "helper invoked on non-IP family!");
331 return NF_DROP;
332 }
333
334 err = helper->help(skb, protoff, ct, ctinfo);
335 if (err != NF_ACCEPT)
336 return err;
337
338 /* Adjust seqs after helper. This is needed due to some helpers (e.g.,
339 * FTP with NAT) adusting the TCP payload size when mangling IP
340 * addresses and/or port numbers in the text-based control connection.
341 */
342 if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
343 !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))
344 return NF_DROP;
345 return NF_ACCEPT;
346}
347
348/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
349 * value if 'skb' is freed.
350 */
351static int handle_fragments(struct net *net, struct sw_flow_key *key,
352 u16 zone, struct sk_buff *skb)
353{
354 struct ovs_skb_cb ovs_cb = *OVS_CB(skb);
355 int err;
356
357 if (key->eth.type == htons(ETH_P_IP)) {
358 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
359
360 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
361 err = ip_defrag(net, skb, user);
362 if (err)
363 return err;
364
365 ovs_cb.mru = IPCB(skb)->frag_max_size;
366#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
367 } else if (key->eth.type == htons(ETH_P_IPV6)) {
368 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
369
370 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
371 err = nf_ct_frag6_gather(net, skb, user);
372 if (err) {
373 if (err != -EINPROGRESS)
374 kfree_skb(skb);
375 return err;
376 }
377
378 key->ip.proto = ipv6_hdr(skb)->nexthdr;
379 ovs_cb.mru = IP6CB(skb)->frag_max_size;
380#endif
381 } else {
382 kfree_skb(skb);
383 return -EPFNOSUPPORT;
384 }
385
386 key->ip.frag = OVS_FRAG_TYPE_NONE;
387 skb_clear_hash(skb);
388 skb->ignore_df = 1;
389 *OVS_CB(skb) = ovs_cb;
390
391 return 0;
392}
393
394static struct nf_conntrack_expect *
395ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone,
396 u16 proto, const struct sk_buff *skb)
397{
398 struct nf_conntrack_tuple tuple;
399
400 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple))
401 return NULL;
402 return __nf_ct_expect_find(net, zone, &tuple);
403}
404
405/* This replicates logic from nf_conntrack_core.c that is not exported. */
406static enum ip_conntrack_info
407ovs_ct_get_info(const struct nf_conntrack_tuple_hash *h)
408{
409 const struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
410
411 if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
412 return IP_CT_ESTABLISHED_REPLY;
413 /* Once we've had two way comms, always ESTABLISHED. */
414 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status))
415 return IP_CT_ESTABLISHED;
416 if (test_bit(IPS_EXPECTED_BIT, &ct->status))
417 return IP_CT_RELATED;
418 return IP_CT_NEW;
419}
420
421/* Find an existing connection which this packet belongs to without
422 * re-attributing statistics or modifying the connection state. This allows an
423 * skb->nfct lost due to an upcall to be recovered during actions execution.
424 *
425 * Must be called with rcu_read_lock.
426 *
427 * On success, populates skb->nfct and skb->nfctinfo, and returns the
428 * connection. Returns NULL if there is no existing entry.
429 */
430static struct nf_conn *
431ovs_ct_find_existing(struct net *net, const struct nf_conntrack_zone *zone,
432 u8 l3num, struct sk_buff *skb)
433{
434 struct nf_conntrack_l3proto *l3proto;
435 struct nf_conntrack_l4proto *l4proto;
436 struct nf_conntrack_tuple tuple;
437 struct nf_conntrack_tuple_hash *h;
438 struct nf_conn *ct;
439 unsigned int dataoff;
440 u8 protonum;
441
442 l3proto = __nf_ct_l3proto_find(l3num);
443 if (l3proto->get_l4proto(skb, skb_network_offset(skb), &dataoff,
444 &protonum) <= 0) {
445 pr_debug("ovs_ct_find_existing: Can't get protonum\n");
446 return NULL;
447 }
448 l4proto = __nf_ct_l4proto_find(l3num, protonum);
449 if (!nf_ct_get_tuple(skb, skb_network_offset(skb), dataoff, l3num,
450 protonum, net, &tuple, l3proto, l4proto)) {
451 pr_debug("ovs_ct_find_existing: Can't get tuple\n");
452 return NULL;
453 }
454
455 /* look for tuple match */
456 h = nf_conntrack_find_get(net, zone, &tuple);
457 if (!h)
458 return NULL; /* Not found. */
459
460 ct = nf_ct_tuplehash_to_ctrack(h);
461
462 skb->nfct = &ct->ct_general;
463 skb->nfctinfo = ovs_ct_get_info(h);
464 return ct;
465}
466
467/* Determine whether skb->nfct is equal to the result of conntrack lookup. */
468static bool skb_nfct_cached(struct net *net,
469 const struct sw_flow_key *key,
470 const struct ovs_conntrack_info *info,
471 struct sk_buff *skb)
472{
473 enum ip_conntrack_info ctinfo;
474 struct nf_conn *ct;
475
476 ct = nf_ct_get(skb, &ctinfo);
477 /* If no ct, check if we have evidence that an existing conntrack entry
478 * might be found for this skb. This happens when we lose a skb->nfct
479 * due to an upcall. If the connection was not confirmed, it is not
480 * cached and needs to be run through conntrack again.
481 */
482 if (!ct && key->ct.state & OVS_CS_F_TRACKED &&
483 !(key->ct.state & OVS_CS_F_INVALID) &&
484 key->ct.zone == info->zone.id)
485 ct = ovs_ct_find_existing(net, &info->zone, info->family, skb);
486 if (!ct)
487 return false;
488 if (!net_eq(net, read_pnet(&ct->ct_net)))
489 return false;
490 if (!nf_ct_zone_equal_any(info->ct, nf_ct_zone(ct)))
491 return false;
492 if (info->helper) {
493 struct nf_conn_help *help;
494
495 help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
496 if (help && rcu_access_pointer(help->helper) != info->helper)
497 return false;
498 }
499
500 return true;
501}
502
503#ifdef CONFIG_NF_NAT_NEEDED
504/* Modelled after nf_nat_ipv[46]_fn().
505 * range is only used for new, uninitialized NAT state.
506 * Returns either NF_ACCEPT or NF_DROP.
507 */
508static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
509 enum ip_conntrack_info ctinfo,
510 const struct nf_nat_range *range,
511 enum nf_nat_manip_type maniptype)
512{
513 int hooknum, nh_off, err = NF_ACCEPT;
514
515 nh_off = skb_network_offset(skb);
516 skb_pull_rcsum(skb, nh_off);
517
518 /* See HOOK2MANIP(). */
519 if (maniptype == NF_NAT_MANIP_SRC)
520 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
521 else
522 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
523
524 switch (ctinfo) {
525 case IP_CT_RELATED:
526 case IP_CT_RELATED_REPLY:
527 if (IS_ENABLED(CONFIG_NF_NAT_IPV4) &&
528 skb->protocol == htons(ETH_P_IP) &&
529 ip_hdr(skb)->protocol == IPPROTO_ICMP) {
530 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
531 hooknum))
532 err = NF_DROP;
533 goto push;
534 } else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) &&
535 skb->protocol == htons(ETH_P_IPV6)) {
536 __be16 frag_off;
537 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
538 int hdrlen = ipv6_skip_exthdr(skb,
539 sizeof(struct ipv6hdr),
540 &nexthdr, &frag_off);
541
542 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
543 if (!nf_nat_icmpv6_reply_translation(skb, ct,
544 ctinfo,
545 hooknum,
546 hdrlen))
547 err = NF_DROP;
548 goto push;
549 }
550 }
551 /* Non-ICMP, fall thru to initialize if needed. */
552 case IP_CT_NEW:
553 /* Seen it before? This can happen for loopback, retrans,
554 * or local packets.
555 */
556 if (!nf_nat_initialized(ct, maniptype)) {
557 /* Initialize according to the NAT action. */
558 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
559 /* Action is set up to establish a new
560 * mapping.
561 */
562 ? nf_nat_setup_info(ct, range, maniptype)
563 : nf_nat_alloc_null_binding(ct, hooknum);
564 if (err != NF_ACCEPT)
565 goto push;
566 }
567 break;
568
569 case IP_CT_ESTABLISHED:
570 case IP_CT_ESTABLISHED_REPLY:
571 break;
572
573 default:
574 err = NF_DROP;
575 goto push;
576 }
577
578 err = nf_nat_packet(ct, ctinfo, hooknum, skb);
579push:
580 skb_push(skb, nh_off);
581 skb_postpush_rcsum(skb, skb->data, nh_off);
582
583 return err;
584}
585
586static void ovs_nat_update_key(struct sw_flow_key *key,
587 const struct sk_buff *skb,
588 enum nf_nat_manip_type maniptype)
589{
590 if (maniptype == NF_NAT_MANIP_SRC) {
591 __be16 src;
592
593 key->ct.state |= OVS_CS_F_SRC_NAT;
594 if (key->eth.type == htons(ETH_P_IP))
595 key->ipv4.addr.src = ip_hdr(skb)->saddr;
596 else if (key->eth.type == htons(ETH_P_IPV6))
597 memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr,
598 sizeof(key->ipv6.addr.src));
599 else
600 return;
601
602 if (key->ip.proto == IPPROTO_UDP)
603 src = udp_hdr(skb)->source;
604 else if (key->ip.proto == IPPROTO_TCP)
605 src = tcp_hdr(skb)->source;
606 else if (key->ip.proto == IPPROTO_SCTP)
607 src = sctp_hdr(skb)->source;
608 else
609 return;
610
611 key->tp.src = src;
612 } else {
613 __be16 dst;
614
615 key->ct.state |= OVS_CS_F_DST_NAT;
616 if (key->eth.type == htons(ETH_P_IP))
617 key->ipv4.addr.dst = ip_hdr(skb)->daddr;
618 else if (key->eth.type == htons(ETH_P_IPV6))
619 memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr,
620 sizeof(key->ipv6.addr.dst));
621 else
622 return;
623
624 if (key->ip.proto == IPPROTO_UDP)
625 dst = udp_hdr(skb)->dest;
626 else if (key->ip.proto == IPPROTO_TCP)
627 dst = tcp_hdr(skb)->dest;
628 else if (key->ip.proto == IPPROTO_SCTP)
629 dst = sctp_hdr(skb)->dest;
630 else
631 return;
632
633 key->tp.dst = dst;
634 }
635}
636
637/* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */
638static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
639 const struct ovs_conntrack_info *info,
640 struct sk_buff *skb, struct nf_conn *ct,
641 enum ip_conntrack_info ctinfo)
642{
643 enum nf_nat_manip_type maniptype;
644 int err;
645
646 if (nf_ct_is_untracked(ct)) {
647 /* A NAT action may only be performed on tracked packets. */
648 return NF_ACCEPT;
649 }
650
651 /* Add NAT extension if not confirmed yet. */
652 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
653 return NF_ACCEPT; /* Can't NAT. */
654
655 /* Determine NAT type.
656 * Check if the NAT type can be deduced from the tracked connection.
657 * Make sure new expected connections (IP_CT_RELATED) are NATted only
658 * when committing.
659 */
660 if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW &&
661 ct->status & IPS_NAT_MASK &&
662 (ctinfo != IP_CT_RELATED || info->commit)) {
663 /* NAT an established or related connection like before. */
664 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
665 /* This is the REPLY direction for a connection
666 * for which NAT was applied in the forward
667 * direction. Do the reverse NAT.
668 */
669 maniptype = ct->status & IPS_SRC_NAT
670 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
671 else
672 maniptype = ct->status & IPS_SRC_NAT
673 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
674 } else if (info->nat & OVS_CT_SRC_NAT) {
675 maniptype = NF_NAT_MANIP_SRC;
676 } else if (info->nat & OVS_CT_DST_NAT) {
677 maniptype = NF_NAT_MANIP_DST;
678 } else {
679 return NF_ACCEPT; /* Connection is not NATed. */
680 }
681 err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype);
682
683 /* Mark NAT done if successful and update the flow key. */
684 if (err == NF_ACCEPT)
685 ovs_nat_update_key(key, skb, maniptype);
686
687 return err;
688}
689#else /* !CONFIG_NF_NAT_NEEDED */
690static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
691 const struct ovs_conntrack_info *info,
692 struct sk_buff *skb, struct nf_conn *ct,
693 enum ip_conntrack_info ctinfo)
694{
695 return NF_ACCEPT;
696}
697#endif
698
699/* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
700 * not done already. Update key with new CT state after passing the packet
701 * through conntrack.
702 * Note that if the packet is deemed invalid by conntrack, skb->nfct will be
703 * set to NULL and 0 will be returned.
704 */
705static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
706 const struct ovs_conntrack_info *info,
707 struct sk_buff *skb)
708{
709 /* If we are recirculating packets to match on conntrack fields and
710 * committing with a separate conntrack action, then we don't need to
711 * actually run the packet through conntrack twice unless it's for a
712 * different zone.
713 */
714 bool cached = skb_nfct_cached(net, key, info, skb);
715 enum ip_conntrack_info ctinfo;
716 struct nf_conn *ct;
717
718 if (!cached) {
719 struct nf_conn *tmpl = info->ct;
720 int err;
721
722 /* Associate skb with specified zone. */
723 if (tmpl) {
724 if (skb->nfct)
725 nf_conntrack_put(skb->nfct);
726 nf_conntrack_get(&tmpl->ct_general);
727 skb->nfct = &tmpl->ct_general;
728 skb->nfctinfo = IP_CT_NEW;
729 }
730
731 err = nf_conntrack_in(net, info->family,
732 NF_INET_PRE_ROUTING, skb);
733 if (err != NF_ACCEPT)
734 return -ENOENT;
735
736 /* Clear CT state NAT flags to mark that we have not yet done
737 * NAT after the nf_conntrack_in() call. We can actually clear
738 * the whole state, as it will be re-initialized below.
739 */
740 key->ct.state = 0;
741
742 /* Update the key, but keep the NAT flags. */
743 ovs_ct_update_key(skb, info, key, true, true);
744 }
745
746 ct = nf_ct_get(skb, &ctinfo);
747 if (ct) {
748 /* Packets starting a new connection must be NATted before the
749 * helper, so that the helper knows about the NAT. We enforce
750 * this by delaying both NAT and helper calls for unconfirmed
751 * connections until the committing CT action. For later
752 * packets NAT and Helper may be called in either order.
753 *
754 * NAT will be done only if the CT action has NAT, and only
755 * once per packet (per zone), as guarded by the NAT bits in
756 * the key->ct.state.
757 */
758 if (info->nat && !(key->ct.state & OVS_CS_F_NAT_MASK) &&
759 (nf_ct_is_confirmed(ct) || info->commit) &&
760 ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) {
761 return -EINVAL;
762 }
763
764 /* Userspace may decide to perform a ct lookup without a helper
765 * specified followed by a (recirculate and) commit with one.
766 * Therefore, for unconfirmed connections which we will commit,
767 * we need to attach the helper here.
768 */
769 if (!nf_ct_is_confirmed(ct) && info->commit &&
770 info->helper && !nfct_help(ct)) {
771 int err = __nf_ct_try_assign_helper(ct, info->ct,
772 GFP_ATOMIC);
773 if (err)
774 return err;
775 }
776
777 /* Call the helper only if:
778 * - nf_conntrack_in() was executed above ("!cached") for a
779 * confirmed connection, or
780 * - When committing an unconfirmed connection.
781 */
782 if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) &&
783 ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
784 return -EINVAL;
785 }
786 }
787
788 return 0;
789}
790
791/* Lookup connection and read fields into key. */
792static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
793 const struct ovs_conntrack_info *info,
794 struct sk_buff *skb)
795{
796 struct nf_conntrack_expect *exp;
797
798 /* If we pass an expected packet through nf_conntrack_in() the
799 * expectation is typically removed, but the packet could still be
800 * lost in upcall processing. To prevent this from happening we
801 * perform an explicit expectation lookup. Expected connections are
802 * always new, and will be passed through conntrack only when they are
803 * committed, as it is OK to remove the expectation at that time.
804 */
805 exp = ovs_ct_expect_find(net, &info->zone, info->family, skb);
806 if (exp) {
807 u8 state;
808
809 /* NOTE: New connections are NATted and Helped only when
810 * committed, so we are not calling into NAT here.
811 */
812 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
813 __ovs_ct_update_key(key, state, &info->zone, exp->master);
814 } else {
815 struct nf_conn *ct;
816 int err;
817
818 err = __ovs_ct_lookup(net, key, info, skb);
819 if (err)
820 return err;
821
822 ct = (struct nf_conn *)skb->nfct;
823 if (ct)
824 nf_ct_deliver_cached_events(ct);
825 }
826
827 return 0;
828}
829
830static bool labels_nonzero(const struct ovs_key_ct_labels *labels)
831{
832 size_t i;
833
834 for (i = 0; i < sizeof(*labels); i++)
835 if (labels->ct_labels[i])
836 return true;
837
838 return false;
839}
840
841/* Lookup connection and confirm if unconfirmed. */
842static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
843 const struct ovs_conntrack_info *info,
844 struct sk_buff *skb)
845{
846 int err;
847
848 err = __ovs_ct_lookup(net, key, info, skb);
849 if (err)
850 return err;
851
852 /* Apply changes before confirming the connection so that the initial
853 * conntrack NEW netlink event carries the values given in the CT
854 * action.
855 */
856 if (info->mark.mask) {
857 err = ovs_ct_set_mark(skb, key, info->mark.value,
858 info->mark.mask);
859 if (err)
860 return err;
861 }
862 if (labels_nonzero(&info->labels.mask)) {
863 err = ovs_ct_set_labels(skb, key, &info->labels.value,
864 &info->labels.mask);
865 if (err)
866 return err;
867 }
868 /* This will take care of sending queued events even if the connection
869 * is already confirmed.
870 */
871 if (nf_conntrack_confirm(skb) != NF_ACCEPT)
872 return -EINVAL;
873
874 return 0;
875}
876
877/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
878 * value if 'skb' is freed.
879 */
880int ovs_ct_execute(struct net *net, struct sk_buff *skb,
881 struct sw_flow_key *key,
882 const struct ovs_conntrack_info *info)
883{
884 int nh_ofs;
885 int err;
886
887 /* The conntrack module expects to be working at L3. */
888 nh_ofs = skb_network_offset(skb);
889 skb_pull_rcsum(skb, nh_ofs);
890
891 if (key->ip.frag != OVS_FRAG_TYPE_NONE) {
892 err = handle_fragments(net, key, info->zone.id, skb);
893 if (err)
894 return err;
895 }
896
897 if (info->commit)
898 err = ovs_ct_commit(net, key, info, skb);
899 else
900 err = ovs_ct_lookup(net, key, info, skb);
901
902 skb_push(skb, nh_ofs);
903 skb_postpush_rcsum(skb, skb->data, nh_ofs);
904 if (err)
905 kfree_skb(skb);
906 return err;
907}
908
909static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
910 const struct sw_flow_key *key, bool log)
911{
912 struct nf_conntrack_helper *helper;
913 struct nf_conn_help *help;
914
915 helper = nf_conntrack_helper_try_module_get(name, info->family,
916 key->ip.proto);
917 if (!helper) {
918 OVS_NLERR(log, "Unknown helper \"%s\"", name);
919 return -EINVAL;
920 }
921
922 help = nf_ct_helper_ext_add(info->ct, helper, GFP_KERNEL);
923 if (!help) {
924 module_put(helper->me);
925 return -ENOMEM;
926 }
927
928 rcu_assign_pointer(help->helper, helper);
929 info->helper = helper;
930 return 0;
931}
932
933#ifdef CONFIG_NF_NAT_NEEDED
934static int parse_nat(const struct nlattr *attr,
935 struct ovs_conntrack_info *info, bool log)
936{
937 struct nlattr *a;
938 int rem;
939 bool have_ip_max = false;
940 bool have_proto_max = false;
941 bool ip_vers = (info->family == NFPROTO_IPV6);
942
943 nla_for_each_nested(a, attr, rem) {
944 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = {
945 [OVS_NAT_ATTR_SRC] = {0, 0},
946 [OVS_NAT_ATTR_DST] = {0, 0},
947 [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr),
948 sizeof(struct in6_addr)},
949 [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr),
950 sizeof(struct in6_addr)},
951 [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)},
952 [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)},
953 [OVS_NAT_ATTR_PERSISTENT] = {0, 0},
954 [OVS_NAT_ATTR_PROTO_HASH] = {0, 0},
955 [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0},
956 };
957 int type = nla_type(a);
958
959 if (type > OVS_NAT_ATTR_MAX) {
960 OVS_NLERR(log,
961 "Unknown NAT attribute (type=%d, max=%d).\n",
962 type, OVS_NAT_ATTR_MAX);
963 return -EINVAL;
964 }
965
966 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) {
967 OVS_NLERR(log,
968 "NAT attribute type %d has unexpected length (%d != %d).\n",
969 type, nla_len(a),
970 ovs_nat_attr_lens[type][ip_vers]);
971 return -EINVAL;
972 }
973
974 switch (type) {
975 case OVS_NAT_ATTR_SRC:
976 case OVS_NAT_ATTR_DST:
977 if (info->nat) {
978 OVS_NLERR(log,
979 "Only one type of NAT may be specified.\n"
980 );
981 return -ERANGE;
982 }
983 info->nat |= OVS_CT_NAT;
984 info->nat |= ((type == OVS_NAT_ATTR_SRC)
985 ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT);
986 break;
987
988 case OVS_NAT_ATTR_IP_MIN:
989 nla_memcpy(&info->range.min_addr, a,
990 sizeof(info->range.min_addr));
991 info->range.flags |= NF_NAT_RANGE_MAP_IPS;
992 break;
993
994 case OVS_NAT_ATTR_IP_MAX:
995 have_ip_max = true;
996 nla_memcpy(&info->range.max_addr, a,
997 sizeof(info->range.max_addr));
998 info->range.flags |= NF_NAT_RANGE_MAP_IPS;
999 break;
1000
1001 case OVS_NAT_ATTR_PROTO_MIN:
1002 info->range.min_proto.all = htons(nla_get_u16(a));
1003 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1004 break;
1005
1006 case OVS_NAT_ATTR_PROTO_MAX:
1007 have_proto_max = true;
1008 info->range.max_proto.all = htons(nla_get_u16(a));
1009 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1010 break;
1011
1012 case OVS_NAT_ATTR_PERSISTENT:
1013 info->range.flags |= NF_NAT_RANGE_PERSISTENT;
1014 break;
1015
1016 case OVS_NAT_ATTR_PROTO_HASH:
1017 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
1018 break;
1019
1020 case OVS_NAT_ATTR_PROTO_RANDOM:
1021 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
1022 break;
1023
1024 default:
1025 OVS_NLERR(log, "Unknown nat attribute (%d).\n", type);
1026 return -EINVAL;
1027 }
1028 }
1029
1030 if (rem > 0) {
1031 OVS_NLERR(log, "NAT attribute has %d unknown bytes.\n", rem);
1032 return -EINVAL;
1033 }
1034 if (!info->nat) {
1035 /* Do not allow flags if no type is given. */
1036 if (info->range.flags) {
1037 OVS_NLERR(log,
1038 "NAT flags may be given only when NAT range (SRC or DST) is also specified.\n"
1039 );
1040 return -EINVAL;
1041 }
1042 info->nat = OVS_CT_NAT; /* NAT existing connections. */
1043 } else if (!info->commit) {
1044 OVS_NLERR(log,
1045 "NAT attributes may be specified only when CT COMMIT flag is also specified.\n"
1046 );
1047 return -EINVAL;
1048 }
1049 /* Allow missing IP_MAX. */
1050 if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) {
1051 memcpy(&info->range.max_addr, &info->range.min_addr,
1052 sizeof(info->range.max_addr));
1053 }
1054 /* Allow missing PROTO_MAX. */
1055 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1056 !have_proto_max) {
1057 info->range.max_proto.all = info->range.min_proto.all;
1058 }
1059 return 0;
1060}
1061#endif
1062
1063static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
1064 [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 },
1065 [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16),
1066 .maxlen = sizeof(u16) },
1067 [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark),
1068 .maxlen = sizeof(struct md_mark) },
1069 [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels),
1070 .maxlen = sizeof(struct md_labels) },
1071 [OVS_CT_ATTR_HELPER] = { .minlen = 1,
1072 .maxlen = NF_CT_HELPER_NAME_LEN },
1073#ifdef CONFIG_NF_NAT_NEEDED
1074 /* NAT length is checked when parsing the nested attributes. */
1075 [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX },
1076#endif
1077};
1078
1079static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
1080 const char **helper, bool log)
1081{
1082 struct nlattr *a;
1083 int rem;
1084
1085 nla_for_each_nested(a, attr, rem) {
1086 int type = nla_type(a);
1087 int maxlen = ovs_ct_attr_lens[type].maxlen;
1088 int minlen = ovs_ct_attr_lens[type].minlen;
1089
1090 if (type > OVS_CT_ATTR_MAX) {
1091 OVS_NLERR(log,
1092 "Unknown conntrack attr (type=%d, max=%d)",
1093 type, OVS_CT_ATTR_MAX);
1094 return -EINVAL;
1095 }
1096 if (nla_len(a) < minlen || nla_len(a) > maxlen) {
1097 OVS_NLERR(log,
1098 "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)",
1099 type, nla_len(a), maxlen);
1100 return -EINVAL;
1101 }
1102
1103 switch (type) {
1104 case OVS_CT_ATTR_COMMIT:
1105 info->commit = true;
1106 break;
1107#ifdef CONFIG_NF_CONNTRACK_ZONES
1108 case OVS_CT_ATTR_ZONE:
1109 info->zone.id = nla_get_u16(a);
1110 break;
1111#endif
1112#ifdef CONFIG_NF_CONNTRACK_MARK
1113 case OVS_CT_ATTR_MARK: {
1114 struct md_mark *mark = nla_data(a);
1115
1116 if (!mark->mask) {
1117 OVS_NLERR(log, "ct_mark mask cannot be 0");
1118 return -EINVAL;
1119 }
1120 info->mark = *mark;
1121 break;
1122 }
1123#endif
1124#ifdef CONFIG_NF_CONNTRACK_LABELS
1125 case OVS_CT_ATTR_LABELS: {
1126 struct md_labels *labels = nla_data(a);
1127
1128 if (!labels_nonzero(&labels->mask)) {
1129 OVS_NLERR(log, "ct_labels mask cannot be 0");
1130 return -EINVAL;
1131 }
1132 info->labels = *labels;
1133 break;
1134 }
1135#endif
1136 case OVS_CT_ATTR_HELPER:
1137 *helper = nla_data(a);
1138 if (!memchr(*helper, '\0', nla_len(a))) {
1139 OVS_NLERR(log, "Invalid conntrack helper");
1140 return -EINVAL;
1141 }
1142 break;
1143#ifdef CONFIG_NF_NAT_NEEDED
1144 case OVS_CT_ATTR_NAT: {
1145 int err = parse_nat(a, info, log);
1146
1147 if (err)
1148 return err;
1149 break;
1150 }
1151#endif
1152 default:
1153 OVS_NLERR(log, "Unknown conntrack attr (%d)",
1154 type);
1155 return -EINVAL;
1156 }
1157 }
1158
1159#ifdef CONFIG_NF_CONNTRACK_MARK
1160 if (!info->commit && info->mark.mask) {
1161 OVS_NLERR(log,
1162 "Setting conntrack mark requires 'commit' flag.");
1163 return -EINVAL;
1164 }
1165#endif
1166#ifdef CONFIG_NF_CONNTRACK_LABELS
1167 if (!info->commit && labels_nonzero(&info->labels.mask)) {
1168 OVS_NLERR(log,
1169 "Setting conntrack labels requires 'commit' flag.");
1170 return -EINVAL;
1171 }
1172#endif
1173 if (rem > 0) {
1174 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem);
1175 return -EINVAL;
1176 }
1177
1178 return 0;
1179}
1180
1181bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr)
1182{
1183 if (attr == OVS_KEY_ATTR_CT_STATE)
1184 return true;
1185 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1186 attr == OVS_KEY_ATTR_CT_ZONE)
1187 return true;
1188 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1189 attr == OVS_KEY_ATTR_CT_MARK)
1190 return true;
1191 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1192 attr == OVS_KEY_ATTR_CT_LABELS) {
1193 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1194
1195 return ovs_net->xt_label;
1196 }
1197
1198 return false;
1199}
1200
1201int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
1202 const struct sw_flow_key *key,
1203 struct sw_flow_actions **sfa, bool log)
1204{
1205 struct ovs_conntrack_info ct_info;
1206 const char *helper = NULL;
1207 u16 family;
1208 int err;
1209
1210 family = key_to_nfproto(key);
1211 if (family == NFPROTO_UNSPEC) {
1212 OVS_NLERR(log, "ct family unspecified");
1213 return -EINVAL;
1214 }
1215
1216 memset(&ct_info, 0, sizeof(ct_info));
1217 ct_info.family = family;
1218
1219 nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID,
1220 NF_CT_DEFAULT_ZONE_DIR, 0);
1221
1222 err = parse_ct(attr, &ct_info, &helper, log);
1223 if (err)
1224 return err;
1225
1226 /* Set up template for tracking connections in specific zones. */
1227 ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL);
1228 if (!ct_info.ct) {
1229 OVS_NLERR(log, "Failed to allocate conntrack template");
1230 return -ENOMEM;
1231 }
1232
1233 __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
1234 nf_conntrack_get(&ct_info.ct->ct_general);
1235
1236 if (helper) {
1237 err = ovs_ct_add_helper(&ct_info, helper, key, log);
1238 if (err)
1239 goto err_free_ct;
1240 }
1241
1242 err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info,
1243 sizeof(ct_info), log);
1244 if (err)
1245 goto err_free_ct;
1246
1247 return 0;
1248err_free_ct:
1249 __ovs_ct_free_action(&ct_info);
1250 return err;
1251}
1252
1253#ifdef CONFIG_NF_NAT_NEEDED
1254static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
1255 struct sk_buff *skb)
1256{
1257 struct nlattr *start;
1258
1259 start = nla_nest_start(skb, OVS_CT_ATTR_NAT);
1260 if (!start)
1261 return false;
1262
1263 if (info->nat & OVS_CT_SRC_NAT) {
1264 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC))
1265 return false;
1266 } else if (info->nat & OVS_CT_DST_NAT) {
1267 if (nla_put_flag(skb, OVS_NAT_ATTR_DST))
1268 return false;
1269 } else {
1270 goto out;
1271 }
1272
1273 if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
1274 if (IS_ENABLED(CONFIG_NF_NAT_IPV4) &&
1275 info->family == NFPROTO_IPV4) {
1276 if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
1277 info->range.min_addr.ip) ||
1278 (info->range.max_addr.ip
1279 != info->range.min_addr.ip &&
1280 (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
1281 info->range.max_addr.ip))))
1282 return false;
1283 } else if (IS_ENABLED(CONFIG_NF_NAT_IPV6) &&
1284 info->family == NFPROTO_IPV6) {
1285 if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
1286 &info->range.min_addr.in6) ||
1287 (memcmp(&info->range.max_addr.in6,
1288 &info->range.min_addr.in6,
1289 sizeof(info->range.max_addr.in6)) &&
1290 (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX,
1291 &info->range.max_addr.in6))))
1292 return false;
1293 } else {
1294 return false;
1295 }
1296 }
1297 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1298 (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN,
1299 ntohs(info->range.min_proto.all)) ||
1300 (info->range.max_proto.all != info->range.min_proto.all &&
1301 nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX,
1302 ntohs(info->range.max_proto.all)))))
1303 return false;
1304
1305 if (info->range.flags & NF_NAT_RANGE_PERSISTENT &&
1306 nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
1307 return false;
1308 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
1309 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
1310 return false;
1311 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
1312 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
1313 return false;
1314out:
1315 nla_nest_end(skb, start);
1316
1317 return true;
1318}
1319#endif
1320
1321int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
1322 struct sk_buff *skb)
1323{
1324 struct nlattr *start;
1325
1326 start = nla_nest_start(skb, OVS_ACTION_ATTR_CT);
1327 if (!start)
1328 return -EMSGSIZE;
1329
1330 if (ct_info->commit && nla_put_flag(skb, OVS_CT_ATTR_COMMIT))
1331 return -EMSGSIZE;
1332 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1333 nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id))
1334 return -EMSGSIZE;
1335 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask &&
1336 nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark),
1337 &ct_info->mark))
1338 return -EMSGSIZE;
1339 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1340 labels_nonzero(&ct_info->labels.mask) &&
1341 nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels),
1342 &ct_info->labels))
1343 return -EMSGSIZE;
1344 if (ct_info->helper) {
1345 if (nla_put_string(skb, OVS_CT_ATTR_HELPER,
1346 ct_info->helper->name))
1347 return -EMSGSIZE;
1348 }
1349#ifdef CONFIG_NF_NAT_NEEDED
1350 if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
1351 return -EMSGSIZE;
1352#endif
1353 nla_nest_end(skb, start);
1354
1355 return 0;
1356}
1357
1358void ovs_ct_free_action(const struct nlattr *a)
1359{
1360 struct ovs_conntrack_info *ct_info = nla_data(a);
1361
1362 __ovs_ct_free_action(ct_info);
1363}
1364
1365static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info)
1366{
1367 if (ct_info->helper)
1368 module_put(ct_info->helper->me);
1369 if (ct_info->ct)
1370 nf_ct_tmpl_free(ct_info->ct);
1371}
1372
1373void ovs_ct_init(struct net *net)
1374{
1375 unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE;
1376 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1377
1378 if (nf_connlabels_get(net, n_bits - 1)) {
1379 ovs_net->xt_label = false;
1380 OVS_NLERR(true, "Failed to set connlabel length");
1381 } else {
1382 ovs_net->xt_label = true;
1383 }
1384}
1385
1386void ovs_ct_exit(struct net *net)
1387{
1388 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1389
1390 if (ovs_net->xt_label)
1391 nf_connlabels_put(net);
1392}
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
33struct ovs_ct_len_tbl {
34 int maxlen;
35 int minlen;
36};
37
38/* Metadata mark for masked write to conntrack mark */
39struct md_mark {
40 u32 value;
41 u32 mask;
42};
43
44/* Metadata label for masked write to conntrack label. */
45struct md_labels {
46 struct ovs_key_ct_labels value;
47 struct ovs_key_ct_labels mask;
48};
49
50enum 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. */
57struct 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
80static DEFINE_STATIC_KEY_FALSE(ovs_ct_limit_enabled);
81
82struct 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
90struct ovs_ct_limit_info {
91 u32 default_limit;
92 struct hlist_head *limits;
93 struct nf_conncount_data *data;
94};
95
96static 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
101static bool labels_nonzero(const struct ovs_key_ct_labels *labels);
102
103static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info);
104
105static 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. */
118static 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
150static 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
164static 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
175static 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
189static 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 */
233static 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 */
274void 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
279int 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
333static 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
353static 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 */
370static 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
411static 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. */
434static 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 */
495static 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
543static struct nf_conntrack_expect *
544ovs_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. */
583static enum ip_conntrack_info
584ovs_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 */
607static struct nf_conn *
608ovs_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
650static
651struct 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. */
679static 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 */
737static 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 fallthrough;
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);
809push:
810 skb_push(skb, nh_off);
811 skb_postpush_rcsum(skb, skb->data, nh_off);
812
813 return err;
814}
815
816static 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. */
868static 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 && ct->status & IPS_DST_NAT) {
909 if (ct->status & IPS_SRC_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 } else if (CTINFO2DIR(ctinfo) == IP_CT_DIR_ORIGINAL) {
918 err = ovs_ct_nat_execute(skb, ct, ctinfo, NULL,
919 NF_NAT_MANIP_SRC);
920 }
921 }
922
923 /* Mark NAT done if successful and update the flow key. */
924 if (err == NF_ACCEPT)
925 ovs_nat_update_key(key, skb, maniptype);
926
927 return err;
928}
929#else /* !CONFIG_NF_NAT */
930static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
931 const struct ovs_conntrack_info *info,
932 struct sk_buff *skb, struct nf_conn *ct,
933 enum ip_conntrack_info ctinfo)
934{
935 return NF_ACCEPT;
936}
937#endif
938
939/* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
940 * not done already. Update key with new CT state after passing the packet
941 * through conntrack.
942 * Note that if the packet is deemed invalid by conntrack, skb->_nfct will be
943 * set to NULL and 0 will be returned.
944 */
945static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
946 const struct ovs_conntrack_info *info,
947 struct sk_buff *skb)
948{
949 /* If we are recirculating packets to match on conntrack fields and
950 * committing with a separate conntrack action, then we don't need to
951 * actually run the packet through conntrack twice unless it's for a
952 * different zone.
953 */
954 bool cached = skb_nfct_cached(net, key, info, skb);
955 enum ip_conntrack_info ctinfo;
956 struct nf_conn *ct;
957
958 if (!cached) {
959 struct nf_hook_state state = {
960 .hook = NF_INET_PRE_ROUTING,
961 .pf = info->family,
962 .net = net,
963 };
964 struct nf_conn *tmpl = info->ct;
965 int err;
966
967 /* Associate skb with specified zone. */
968 if (tmpl) {
969 if (skb_nfct(skb))
970 nf_conntrack_put(skb_nfct(skb));
971 nf_conntrack_get(&tmpl->ct_general);
972 nf_ct_set(skb, tmpl, IP_CT_NEW);
973 }
974
975 err = nf_conntrack_in(skb, &state);
976 if (err != NF_ACCEPT)
977 return -ENOENT;
978
979 /* Clear CT state NAT flags to mark that we have not yet done
980 * NAT after the nf_conntrack_in() call. We can actually clear
981 * the whole state, as it will be re-initialized below.
982 */
983 key->ct_state = 0;
984
985 /* Update the key, but keep the NAT flags. */
986 ovs_ct_update_key(skb, info, key, true, true);
987 }
988
989 ct = nf_ct_get(skb, &ctinfo);
990 if (ct) {
991 bool add_helper = false;
992
993 /* Packets starting a new connection must be NATted before the
994 * helper, so that the helper knows about the NAT. We enforce
995 * this by delaying both NAT and helper calls for unconfirmed
996 * connections until the committing CT action. For later
997 * packets NAT and Helper may be called in either order.
998 *
999 * NAT will be done only if the CT action has NAT, and only
1000 * once per packet (per zone), as guarded by the NAT bits in
1001 * the key->ct_state.
1002 */
1003 if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) &&
1004 (nf_ct_is_confirmed(ct) || info->commit) &&
1005 ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) {
1006 return -EINVAL;
1007 }
1008
1009 /* Userspace may decide to perform a ct lookup without a helper
1010 * specified followed by a (recirculate and) commit with one,
1011 * or attach a helper in a later commit. Therefore, for
1012 * connections which we will commit, we may need to attach
1013 * the helper here.
1014 */
1015 if (info->commit && info->helper && !nfct_help(ct)) {
1016 int err = __nf_ct_try_assign_helper(ct, info->ct,
1017 GFP_ATOMIC);
1018 if (err)
1019 return err;
1020 add_helper = true;
1021
1022 /* helper installed, add seqadj if NAT is required */
1023 if (info->nat && !nfct_seqadj(ct)) {
1024 if (!nfct_seqadj_ext_add(ct))
1025 return -EINVAL;
1026 }
1027 }
1028
1029 /* Call the helper only if:
1030 * - nf_conntrack_in() was executed above ("!cached") or a
1031 * helper was just attached ("add_helper") for a confirmed
1032 * connection, or
1033 * - When committing an unconfirmed connection.
1034 */
1035 if ((nf_ct_is_confirmed(ct) ? !cached || add_helper :
1036 info->commit) &&
1037 ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
1038 return -EINVAL;
1039 }
1040 }
1041
1042 return 0;
1043}
1044
1045/* Lookup connection and read fields into key. */
1046static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
1047 const struct ovs_conntrack_info *info,
1048 struct sk_buff *skb)
1049{
1050 struct nf_conntrack_expect *exp;
1051
1052 /* If we pass an expected packet through nf_conntrack_in() the
1053 * expectation is typically removed, but the packet could still be
1054 * lost in upcall processing. To prevent this from happening we
1055 * perform an explicit expectation lookup. Expected connections are
1056 * always new, and will be passed through conntrack only when they are
1057 * committed, as it is OK to remove the expectation at that time.
1058 */
1059 exp = ovs_ct_expect_find(net, &info->zone, info->family, skb);
1060 if (exp) {
1061 u8 state;
1062
1063 /* NOTE: New connections are NATted and Helped only when
1064 * committed, so we are not calling into NAT here.
1065 */
1066 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
1067 __ovs_ct_update_key(key, state, &info->zone, exp->master);
1068 } else {
1069 struct nf_conn *ct;
1070 int err;
1071
1072 err = __ovs_ct_lookup(net, key, info, skb);
1073 if (err)
1074 return err;
1075
1076 ct = (struct nf_conn *)skb_nfct(skb);
1077 if (ct)
1078 nf_ct_deliver_cached_events(ct);
1079 }
1080
1081 return 0;
1082}
1083
1084static bool labels_nonzero(const struct ovs_key_ct_labels *labels)
1085{
1086 size_t i;
1087
1088 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
1089 if (labels->ct_labels_32[i])
1090 return true;
1091
1092 return false;
1093}
1094
1095#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1096static struct hlist_head *ct_limit_hash_bucket(
1097 const struct ovs_ct_limit_info *info, u16 zone)
1098{
1099 return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)];
1100}
1101
1102/* Call with ovs_mutex */
1103static void ct_limit_set(const struct ovs_ct_limit_info *info,
1104 struct ovs_ct_limit *new_ct_limit)
1105{
1106 struct ovs_ct_limit *ct_limit;
1107 struct hlist_head *head;
1108
1109 head = ct_limit_hash_bucket(info, new_ct_limit->zone);
1110 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1111 if (ct_limit->zone == new_ct_limit->zone) {
1112 hlist_replace_rcu(&ct_limit->hlist_node,
1113 &new_ct_limit->hlist_node);
1114 kfree_rcu(ct_limit, rcu);
1115 return;
1116 }
1117 }
1118
1119 hlist_add_head_rcu(&new_ct_limit->hlist_node, head);
1120}
1121
1122/* Call with ovs_mutex */
1123static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone)
1124{
1125 struct ovs_ct_limit *ct_limit;
1126 struct hlist_head *head;
1127 struct hlist_node *n;
1128
1129 head = ct_limit_hash_bucket(info, zone);
1130 hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) {
1131 if (ct_limit->zone == zone) {
1132 hlist_del_rcu(&ct_limit->hlist_node);
1133 kfree_rcu(ct_limit, rcu);
1134 return;
1135 }
1136 }
1137}
1138
1139/* Call with RCU read lock */
1140static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone)
1141{
1142 struct ovs_ct_limit *ct_limit;
1143 struct hlist_head *head;
1144
1145 head = ct_limit_hash_bucket(info, zone);
1146 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1147 if (ct_limit->zone == zone)
1148 return ct_limit->limit;
1149 }
1150
1151 return info->default_limit;
1152}
1153
1154static int ovs_ct_check_limit(struct net *net,
1155 const struct ovs_conntrack_info *info,
1156 const struct nf_conntrack_tuple *tuple)
1157{
1158 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1159 const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
1160 u32 per_zone_limit, connections;
1161 u32 conncount_key;
1162
1163 conncount_key = info->zone.id;
1164
1165 per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id);
1166 if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED)
1167 return 0;
1168
1169 connections = nf_conncount_count(net, ct_limit_info->data,
1170 &conncount_key, tuple, &info->zone);
1171 if (connections > per_zone_limit)
1172 return -ENOMEM;
1173
1174 return 0;
1175}
1176#endif
1177
1178/* Lookup connection and confirm if unconfirmed. */
1179static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
1180 const struct ovs_conntrack_info *info,
1181 struct sk_buff *skb)
1182{
1183 enum ip_conntrack_info ctinfo;
1184 struct nf_conn *ct;
1185 int err;
1186
1187 err = __ovs_ct_lookup(net, key, info, skb);
1188 if (err)
1189 return err;
1190
1191 /* The connection could be invalid, in which case this is a no-op.*/
1192 ct = nf_ct_get(skb, &ctinfo);
1193 if (!ct)
1194 return 0;
1195
1196#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1197 if (static_branch_unlikely(&ovs_ct_limit_enabled)) {
1198 if (!nf_ct_is_confirmed(ct)) {
1199 err = ovs_ct_check_limit(net, info,
1200 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
1201 if (err) {
1202 net_warn_ratelimited("openvswitch: zone: %u "
1203 "exceeds conntrack limit\n",
1204 info->zone.id);
1205 return err;
1206 }
1207 }
1208 }
1209#endif
1210
1211 /* Set the conntrack event mask if given. NEW and DELETE events have
1212 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener
1213 * typically would receive many kinds of updates. Setting the event
1214 * mask allows those events to be filtered. The set event mask will
1215 * remain in effect for the lifetime of the connection unless changed
1216 * by a further CT action with both the commit flag and the eventmask
1217 * option. */
1218 if (info->have_eventmask) {
1219 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct);
1220
1221 if (cache)
1222 cache->ctmask = info->eventmask;
1223 }
1224
1225 /* Apply changes before confirming the connection so that the initial
1226 * conntrack NEW netlink event carries the values given in the CT
1227 * action.
1228 */
1229 if (info->mark.mask) {
1230 err = ovs_ct_set_mark(ct, key, info->mark.value,
1231 info->mark.mask);
1232 if (err)
1233 return err;
1234 }
1235 if (!nf_ct_is_confirmed(ct)) {
1236 err = ovs_ct_init_labels(ct, key, &info->labels.value,
1237 &info->labels.mask);
1238 if (err)
1239 return err;
1240 } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1241 labels_nonzero(&info->labels.mask)) {
1242 err = ovs_ct_set_labels(ct, key, &info->labels.value,
1243 &info->labels.mask);
1244 if (err)
1245 return err;
1246 }
1247 /* This will take care of sending queued events even if the connection
1248 * is already confirmed.
1249 */
1250 if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1251 return -EINVAL;
1252
1253 return 0;
1254}
1255
1256/* Trim the skb to the length specified by the IP/IPv6 header,
1257 * removing any trailing lower-layer padding. This prepares the skb
1258 * for higher-layer processing that assumes skb->len excludes padding
1259 * (such as nf_ip_checksum). The caller needs to pull the skb to the
1260 * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
1261 */
1262static int ovs_skb_network_trim(struct sk_buff *skb)
1263{
1264 unsigned int len;
1265 int err;
1266
1267 switch (skb->protocol) {
1268 case htons(ETH_P_IP):
1269 len = ntohs(ip_hdr(skb)->tot_len);
1270 break;
1271 case htons(ETH_P_IPV6):
1272 len = sizeof(struct ipv6hdr)
1273 + ntohs(ipv6_hdr(skb)->payload_len);
1274 break;
1275 default:
1276 len = skb->len;
1277 }
1278
1279 err = pskb_trim_rcsum(skb, len);
1280 if (err)
1281 kfree_skb(skb);
1282
1283 return err;
1284}
1285
1286/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
1287 * value if 'skb' is freed.
1288 */
1289int ovs_ct_execute(struct net *net, struct sk_buff *skb,
1290 struct sw_flow_key *key,
1291 const struct ovs_conntrack_info *info)
1292{
1293 int nh_ofs;
1294 int err;
1295
1296 /* The conntrack module expects to be working at L3. */
1297 nh_ofs = skb_network_offset(skb);
1298 skb_pull_rcsum(skb, nh_ofs);
1299
1300 err = ovs_skb_network_trim(skb);
1301 if (err)
1302 return err;
1303
1304 if (key->ip.frag != OVS_FRAG_TYPE_NONE) {
1305 err = handle_fragments(net, key, info->zone.id, skb);
1306 if (err)
1307 return err;
1308 }
1309
1310 if (info->commit)
1311 err = ovs_ct_commit(net, key, info, skb);
1312 else
1313 err = ovs_ct_lookup(net, key, info, skb);
1314
1315 skb_push(skb, nh_ofs);
1316 skb_postpush_rcsum(skb, skb->data, nh_ofs);
1317 if (err)
1318 kfree_skb(skb);
1319 return err;
1320}
1321
1322int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key)
1323{
1324 if (skb_nfct(skb)) {
1325 nf_conntrack_put(skb_nfct(skb));
1326 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
1327 ovs_ct_fill_key(skb, key);
1328 }
1329
1330 return 0;
1331}
1332
1333static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
1334 const struct sw_flow_key *key, bool log)
1335{
1336 struct nf_conntrack_helper *helper;
1337 struct nf_conn_help *help;
1338 int ret = 0;
1339
1340 helper = nf_conntrack_helper_try_module_get(name, info->family,
1341 key->ip.proto);
1342 if (!helper) {
1343 OVS_NLERR(log, "Unknown helper \"%s\"", name);
1344 return -EINVAL;
1345 }
1346
1347 help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL);
1348 if (!help) {
1349 nf_conntrack_helper_put(helper);
1350 return -ENOMEM;
1351 }
1352
1353#if IS_ENABLED(CONFIG_NF_NAT)
1354 if (info->nat) {
1355 ret = nf_nat_helper_try_module_get(name, info->family,
1356 key->ip.proto);
1357 if (ret) {
1358 nf_conntrack_helper_put(helper);
1359 OVS_NLERR(log, "Failed to load \"%s\" NAT helper, error: %d",
1360 name, ret);
1361 return ret;
1362 }
1363 }
1364#endif
1365 rcu_assign_pointer(help->helper, helper);
1366 info->helper = helper;
1367 return ret;
1368}
1369
1370#if IS_ENABLED(CONFIG_NF_NAT)
1371static int parse_nat(const struct nlattr *attr,
1372 struct ovs_conntrack_info *info, bool log)
1373{
1374 struct nlattr *a;
1375 int rem;
1376 bool have_ip_max = false;
1377 bool have_proto_max = false;
1378 bool ip_vers = (info->family == NFPROTO_IPV6);
1379
1380 nla_for_each_nested(a, attr, rem) {
1381 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = {
1382 [OVS_NAT_ATTR_SRC] = {0, 0},
1383 [OVS_NAT_ATTR_DST] = {0, 0},
1384 [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr),
1385 sizeof(struct in6_addr)},
1386 [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr),
1387 sizeof(struct in6_addr)},
1388 [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)},
1389 [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)},
1390 [OVS_NAT_ATTR_PERSISTENT] = {0, 0},
1391 [OVS_NAT_ATTR_PROTO_HASH] = {0, 0},
1392 [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0},
1393 };
1394 int type = nla_type(a);
1395
1396 if (type > OVS_NAT_ATTR_MAX) {
1397 OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)",
1398 type, OVS_NAT_ATTR_MAX);
1399 return -EINVAL;
1400 }
1401
1402 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) {
1403 OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)",
1404 type, nla_len(a),
1405 ovs_nat_attr_lens[type][ip_vers]);
1406 return -EINVAL;
1407 }
1408
1409 switch (type) {
1410 case OVS_NAT_ATTR_SRC:
1411 case OVS_NAT_ATTR_DST:
1412 if (info->nat) {
1413 OVS_NLERR(log, "Only one type of NAT may be specified");
1414 return -ERANGE;
1415 }
1416 info->nat |= OVS_CT_NAT;
1417 info->nat |= ((type == OVS_NAT_ATTR_SRC)
1418 ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT);
1419 break;
1420
1421 case OVS_NAT_ATTR_IP_MIN:
1422 nla_memcpy(&info->range.min_addr, a,
1423 sizeof(info->range.min_addr));
1424 info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1425 break;
1426
1427 case OVS_NAT_ATTR_IP_MAX:
1428 have_ip_max = true;
1429 nla_memcpy(&info->range.max_addr, a,
1430 sizeof(info->range.max_addr));
1431 info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1432 break;
1433
1434 case OVS_NAT_ATTR_PROTO_MIN:
1435 info->range.min_proto.all = htons(nla_get_u16(a));
1436 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1437 break;
1438
1439 case OVS_NAT_ATTR_PROTO_MAX:
1440 have_proto_max = true;
1441 info->range.max_proto.all = htons(nla_get_u16(a));
1442 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1443 break;
1444
1445 case OVS_NAT_ATTR_PERSISTENT:
1446 info->range.flags |= NF_NAT_RANGE_PERSISTENT;
1447 break;
1448
1449 case OVS_NAT_ATTR_PROTO_HASH:
1450 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
1451 break;
1452
1453 case OVS_NAT_ATTR_PROTO_RANDOM:
1454 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
1455 break;
1456
1457 default:
1458 OVS_NLERR(log, "Unknown nat attribute (%d)", type);
1459 return -EINVAL;
1460 }
1461 }
1462
1463 if (rem > 0) {
1464 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem);
1465 return -EINVAL;
1466 }
1467 if (!info->nat) {
1468 /* Do not allow flags if no type is given. */
1469 if (info->range.flags) {
1470 OVS_NLERR(log,
1471 "NAT flags may be given only when NAT range (SRC or DST) is also specified."
1472 );
1473 return -EINVAL;
1474 }
1475 info->nat = OVS_CT_NAT; /* NAT existing connections. */
1476 } else if (!info->commit) {
1477 OVS_NLERR(log,
1478 "NAT attributes may be specified only when CT COMMIT flag is also specified."
1479 );
1480 return -EINVAL;
1481 }
1482 /* Allow missing IP_MAX. */
1483 if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) {
1484 memcpy(&info->range.max_addr, &info->range.min_addr,
1485 sizeof(info->range.max_addr));
1486 }
1487 /* Allow missing PROTO_MAX. */
1488 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1489 !have_proto_max) {
1490 info->range.max_proto.all = info->range.min_proto.all;
1491 }
1492 return 0;
1493}
1494#endif
1495
1496static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
1497 [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 },
1498 [OVS_CT_ATTR_FORCE_COMMIT] = { .minlen = 0, .maxlen = 0 },
1499 [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16),
1500 .maxlen = sizeof(u16) },
1501 [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark),
1502 .maxlen = sizeof(struct md_mark) },
1503 [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels),
1504 .maxlen = sizeof(struct md_labels) },
1505 [OVS_CT_ATTR_HELPER] = { .minlen = 1,
1506 .maxlen = NF_CT_HELPER_NAME_LEN },
1507#if IS_ENABLED(CONFIG_NF_NAT)
1508 /* NAT length is checked when parsing the nested attributes. */
1509 [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX },
1510#endif
1511 [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32),
1512 .maxlen = sizeof(u32) },
1513 [OVS_CT_ATTR_TIMEOUT] = { .minlen = 1,
1514 .maxlen = CTNL_TIMEOUT_NAME_MAX },
1515};
1516
1517static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
1518 const char **helper, bool log)
1519{
1520 struct nlattr *a;
1521 int rem;
1522
1523 nla_for_each_nested(a, attr, rem) {
1524 int type = nla_type(a);
1525 int maxlen;
1526 int minlen;
1527
1528 if (type > OVS_CT_ATTR_MAX) {
1529 OVS_NLERR(log,
1530 "Unknown conntrack attr (type=%d, max=%d)",
1531 type, OVS_CT_ATTR_MAX);
1532 return -EINVAL;
1533 }
1534
1535 maxlen = ovs_ct_attr_lens[type].maxlen;
1536 minlen = ovs_ct_attr_lens[type].minlen;
1537 if (nla_len(a) < minlen || nla_len(a) > maxlen) {
1538 OVS_NLERR(log,
1539 "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)",
1540 type, nla_len(a), maxlen);
1541 return -EINVAL;
1542 }
1543
1544 switch (type) {
1545 case OVS_CT_ATTR_FORCE_COMMIT:
1546 info->force = true;
1547 fallthrough;
1548 case OVS_CT_ATTR_COMMIT:
1549 info->commit = true;
1550 break;
1551#ifdef CONFIG_NF_CONNTRACK_ZONES
1552 case OVS_CT_ATTR_ZONE:
1553 info->zone.id = nla_get_u16(a);
1554 break;
1555#endif
1556#ifdef CONFIG_NF_CONNTRACK_MARK
1557 case OVS_CT_ATTR_MARK: {
1558 struct md_mark *mark = nla_data(a);
1559
1560 if (!mark->mask) {
1561 OVS_NLERR(log, "ct_mark mask cannot be 0");
1562 return -EINVAL;
1563 }
1564 info->mark = *mark;
1565 break;
1566 }
1567#endif
1568#ifdef CONFIG_NF_CONNTRACK_LABELS
1569 case OVS_CT_ATTR_LABELS: {
1570 struct md_labels *labels = nla_data(a);
1571
1572 if (!labels_nonzero(&labels->mask)) {
1573 OVS_NLERR(log, "ct_labels mask cannot be 0");
1574 return -EINVAL;
1575 }
1576 info->labels = *labels;
1577 break;
1578 }
1579#endif
1580 case OVS_CT_ATTR_HELPER:
1581 *helper = nla_data(a);
1582 if (!memchr(*helper, '\0', nla_len(a))) {
1583 OVS_NLERR(log, "Invalid conntrack helper");
1584 return -EINVAL;
1585 }
1586 break;
1587#if IS_ENABLED(CONFIG_NF_NAT)
1588 case OVS_CT_ATTR_NAT: {
1589 int err = parse_nat(a, info, log);
1590
1591 if (err)
1592 return err;
1593 break;
1594 }
1595#endif
1596 case OVS_CT_ATTR_EVENTMASK:
1597 info->have_eventmask = true;
1598 info->eventmask = nla_get_u32(a);
1599 break;
1600#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1601 case OVS_CT_ATTR_TIMEOUT:
1602 memcpy(info->timeout, nla_data(a), nla_len(a));
1603 if (!memchr(info->timeout, '\0', nla_len(a))) {
1604 OVS_NLERR(log, "Invalid conntrack timeout");
1605 return -EINVAL;
1606 }
1607 break;
1608#endif
1609
1610 default:
1611 OVS_NLERR(log, "Unknown conntrack attr (%d)",
1612 type);
1613 return -EINVAL;
1614 }
1615 }
1616
1617#ifdef CONFIG_NF_CONNTRACK_MARK
1618 if (!info->commit && info->mark.mask) {
1619 OVS_NLERR(log,
1620 "Setting conntrack mark requires 'commit' flag.");
1621 return -EINVAL;
1622 }
1623#endif
1624#ifdef CONFIG_NF_CONNTRACK_LABELS
1625 if (!info->commit && labels_nonzero(&info->labels.mask)) {
1626 OVS_NLERR(log,
1627 "Setting conntrack labels requires 'commit' flag.");
1628 return -EINVAL;
1629 }
1630#endif
1631 if (rem > 0) {
1632 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem);
1633 return -EINVAL;
1634 }
1635
1636 return 0;
1637}
1638
1639bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr)
1640{
1641 if (attr == OVS_KEY_ATTR_CT_STATE)
1642 return true;
1643 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1644 attr == OVS_KEY_ATTR_CT_ZONE)
1645 return true;
1646 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1647 attr == OVS_KEY_ATTR_CT_MARK)
1648 return true;
1649 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1650 attr == OVS_KEY_ATTR_CT_LABELS) {
1651 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1652
1653 return ovs_net->xt_label;
1654 }
1655
1656 return false;
1657}
1658
1659int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
1660 const struct sw_flow_key *key,
1661 struct sw_flow_actions **sfa, bool log)
1662{
1663 struct ovs_conntrack_info ct_info;
1664 const char *helper = NULL;
1665 u16 family;
1666 int err;
1667
1668 family = key_to_nfproto(key);
1669 if (family == NFPROTO_UNSPEC) {
1670 OVS_NLERR(log, "ct family unspecified");
1671 return -EINVAL;
1672 }
1673
1674 memset(&ct_info, 0, sizeof(ct_info));
1675 ct_info.family = family;
1676
1677 nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID,
1678 NF_CT_DEFAULT_ZONE_DIR, 0);
1679
1680 err = parse_ct(attr, &ct_info, &helper, log);
1681 if (err)
1682 return err;
1683
1684 /* Set up template for tracking connections in specific zones. */
1685 ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL);
1686 if (!ct_info.ct) {
1687 OVS_NLERR(log, "Failed to allocate conntrack template");
1688 return -ENOMEM;
1689 }
1690
1691 if (ct_info.timeout[0]) {
1692 if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto,
1693 ct_info.timeout))
1694 pr_info_ratelimited("Failed to associated timeout "
1695 "policy `%s'\n", ct_info.timeout);
1696 else
1697 ct_info.nf_ct_timeout = rcu_dereference(
1698 nf_ct_timeout_find(ct_info.ct)->timeout);
1699
1700 }
1701
1702 if (helper) {
1703 err = ovs_ct_add_helper(&ct_info, helper, key, log);
1704 if (err)
1705 goto err_free_ct;
1706 }
1707
1708 err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info,
1709 sizeof(ct_info), log);
1710 if (err)
1711 goto err_free_ct;
1712
1713 __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
1714 nf_conntrack_get(&ct_info.ct->ct_general);
1715 return 0;
1716err_free_ct:
1717 __ovs_ct_free_action(&ct_info);
1718 return err;
1719}
1720
1721#if IS_ENABLED(CONFIG_NF_NAT)
1722static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
1723 struct sk_buff *skb)
1724{
1725 struct nlattr *start;
1726
1727 start = nla_nest_start_noflag(skb, OVS_CT_ATTR_NAT);
1728 if (!start)
1729 return false;
1730
1731 if (info->nat & OVS_CT_SRC_NAT) {
1732 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC))
1733 return false;
1734 } else if (info->nat & OVS_CT_DST_NAT) {
1735 if (nla_put_flag(skb, OVS_NAT_ATTR_DST))
1736 return false;
1737 } else {
1738 goto out;
1739 }
1740
1741 if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
1742 if (IS_ENABLED(CONFIG_NF_NAT) &&
1743 info->family == NFPROTO_IPV4) {
1744 if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
1745 info->range.min_addr.ip) ||
1746 (info->range.max_addr.ip
1747 != info->range.min_addr.ip &&
1748 (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
1749 info->range.max_addr.ip))))
1750 return false;
1751 } else if (IS_ENABLED(CONFIG_IPV6) &&
1752 info->family == NFPROTO_IPV6) {
1753 if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
1754 &info->range.min_addr.in6) ||
1755 (memcmp(&info->range.max_addr.in6,
1756 &info->range.min_addr.in6,
1757 sizeof(info->range.max_addr.in6)) &&
1758 (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX,
1759 &info->range.max_addr.in6))))
1760 return false;
1761 } else {
1762 return false;
1763 }
1764 }
1765 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1766 (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN,
1767 ntohs(info->range.min_proto.all)) ||
1768 (info->range.max_proto.all != info->range.min_proto.all &&
1769 nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX,
1770 ntohs(info->range.max_proto.all)))))
1771 return false;
1772
1773 if (info->range.flags & NF_NAT_RANGE_PERSISTENT &&
1774 nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
1775 return false;
1776 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
1777 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
1778 return false;
1779 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
1780 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
1781 return false;
1782out:
1783 nla_nest_end(skb, start);
1784
1785 return true;
1786}
1787#endif
1788
1789int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
1790 struct sk_buff *skb)
1791{
1792 struct nlattr *start;
1793
1794 start = nla_nest_start_noflag(skb, OVS_ACTION_ATTR_CT);
1795 if (!start)
1796 return -EMSGSIZE;
1797
1798 if (ct_info->commit && nla_put_flag(skb, ct_info->force
1799 ? OVS_CT_ATTR_FORCE_COMMIT
1800 : OVS_CT_ATTR_COMMIT))
1801 return -EMSGSIZE;
1802 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1803 nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id))
1804 return -EMSGSIZE;
1805 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask &&
1806 nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark),
1807 &ct_info->mark))
1808 return -EMSGSIZE;
1809 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1810 labels_nonzero(&ct_info->labels.mask) &&
1811 nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels),
1812 &ct_info->labels))
1813 return -EMSGSIZE;
1814 if (ct_info->helper) {
1815 if (nla_put_string(skb, OVS_CT_ATTR_HELPER,
1816 ct_info->helper->name))
1817 return -EMSGSIZE;
1818 }
1819 if (ct_info->have_eventmask &&
1820 nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask))
1821 return -EMSGSIZE;
1822 if (ct_info->timeout[0]) {
1823 if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout))
1824 return -EMSGSIZE;
1825 }
1826
1827#if IS_ENABLED(CONFIG_NF_NAT)
1828 if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
1829 return -EMSGSIZE;
1830#endif
1831 nla_nest_end(skb, start);
1832
1833 return 0;
1834}
1835
1836void ovs_ct_free_action(const struct nlattr *a)
1837{
1838 struct ovs_conntrack_info *ct_info = nla_data(a);
1839
1840 __ovs_ct_free_action(ct_info);
1841}
1842
1843static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info)
1844{
1845 if (ct_info->helper) {
1846#if IS_ENABLED(CONFIG_NF_NAT)
1847 if (ct_info->nat)
1848 nf_nat_helper_put(ct_info->helper);
1849#endif
1850 nf_conntrack_helper_put(ct_info->helper);
1851 }
1852 if (ct_info->ct) {
1853 if (ct_info->timeout[0])
1854 nf_ct_destroy_timeout(ct_info->ct);
1855 nf_ct_tmpl_free(ct_info->ct);
1856 }
1857}
1858
1859#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1860static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net)
1861{
1862 int i, err;
1863
1864 ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info),
1865 GFP_KERNEL);
1866 if (!ovs_net->ct_limit_info)
1867 return -ENOMEM;
1868
1869 ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT;
1870 ovs_net->ct_limit_info->limits =
1871 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head),
1872 GFP_KERNEL);
1873 if (!ovs_net->ct_limit_info->limits) {
1874 kfree(ovs_net->ct_limit_info);
1875 return -ENOMEM;
1876 }
1877
1878 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++)
1879 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]);
1880
1881 ovs_net->ct_limit_info->data =
1882 nf_conncount_init(net, NFPROTO_INET, sizeof(u32));
1883
1884 if (IS_ERR(ovs_net->ct_limit_info->data)) {
1885 err = PTR_ERR(ovs_net->ct_limit_info->data);
1886 kfree(ovs_net->ct_limit_info->limits);
1887 kfree(ovs_net->ct_limit_info);
1888 pr_err("openvswitch: failed to init nf_conncount %d\n", err);
1889 return err;
1890 }
1891 return 0;
1892}
1893
1894static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net)
1895{
1896 const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info;
1897 int i;
1898
1899 nf_conncount_destroy(net, NFPROTO_INET, info->data);
1900 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
1901 struct hlist_head *head = &info->limits[i];
1902 struct ovs_ct_limit *ct_limit;
1903
1904 hlist_for_each_entry_rcu(ct_limit, head, hlist_node,
1905 lockdep_ovsl_is_held())
1906 kfree_rcu(ct_limit, rcu);
1907 }
1908 kfree(ovs_net->ct_limit_info->limits);
1909 kfree(ovs_net->ct_limit_info);
1910}
1911
1912static struct sk_buff *
1913ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd,
1914 struct ovs_header **ovs_reply_header)
1915{
1916 struct ovs_header *ovs_header = info->userhdr;
1917 struct sk_buff *skb;
1918
1919 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1920 if (!skb)
1921 return ERR_PTR(-ENOMEM);
1922
1923 *ovs_reply_header = genlmsg_put(skb, info->snd_portid,
1924 info->snd_seq,
1925 &dp_ct_limit_genl_family, 0, cmd);
1926
1927 if (!*ovs_reply_header) {
1928 nlmsg_free(skb);
1929 return ERR_PTR(-EMSGSIZE);
1930 }
1931 (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex;
1932
1933 return skb;
1934}
1935
1936static bool check_zone_id(int zone_id, u16 *pzone)
1937{
1938 if (zone_id >= 0 && zone_id <= 65535) {
1939 *pzone = (u16)zone_id;
1940 return true;
1941 }
1942 return false;
1943}
1944
1945static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit,
1946 struct ovs_ct_limit_info *info)
1947{
1948 struct ovs_zone_limit *zone_limit;
1949 int rem;
1950 u16 zone;
1951
1952 rem = NLA_ALIGN(nla_len(nla_zone_limit));
1953 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
1954
1955 while (rem >= sizeof(*zone_limit)) {
1956 if (unlikely(zone_limit->zone_id ==
1957 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
1958 ovs_lock();
1959 info->default_limit = zone_limit->limit;
1960 ovs_unlock();
1961 } else if (unlikely(!check_zone_id(
1962 zone_limit->zone_id, &zone))) {
1963 OVS_NLERR(true, "zone id is out of range");
1964 } else {
1965 struct ovs_ct_limit *ct_limit;
1966
1967 ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL);
1968 if (!ct_limit)
1969 return -ENOMEM;
1970
1971 ct_limit->zone = zone;
1972 ct_limit->limit = zone_limit->limit;
1973
1974 ovs_lock();
1975 ct_limit_set(info, ct_limit);
1976 ovs_unlock();
1977 }
1978 rem -= NLA_ALIGN(sizeof(*zone_limit));
1979 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
1980 NLA_ALIGN(sizeof(*zone_limit)));
1981 }
1982
1983 if (rem)
1984 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem);
1985
1986 return 0;
1987}
1988
1989static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit,
1990 struct ovs_ct_limit_info *info)
1991{
1992 struct ovs_zone_limit *zone_limit;
1993 int rem;
1994 u16 zone;
1995
1996 rem = NLA_ALIGN(nla_len(nla_zone_limit));
1997 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
1998
1999 while (rem >= sizeof(*zone_limit)) {
2000 if (unlikely(zone_limit->zone_id ==
2001 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
2002 ovs_lock();
2003 info->default_limit = OVS_CT_LIMIT_DEFAULT;
2004 ovs_unlock();
2005 } else if (unlikely(!check_zone_id(
2006 zone_limit->zone_id, &zone))) {
2007 OVS_NLERR(true, "zone id is out of range");
2008 } else {
2009 ovs_lock();
2010 ct_limit_del(info, zone);
2011 ovs_unlock();
2012 }
2013 rem -= NLA_ALIGN(sizeof(*zone_limit));
2014 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2015 NLA_ALIGN(sizeof(*zone_limit)));
2016 }
2017
2018 if (rem)
2019 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem);
2020
2021 return 0;
2022}
2023
2024static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info,
2025 struct sk_buff *reply)
2026{
2027 struct ovs_zone_limit zone_limit;
2028 int err;
2029
2030 zone_limit.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE;
2031 zone_limit.limit = info->default_limit;
2032 err = nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2033 if (err)
2034 return err;
2035
2036 return 0;
2037}
2038
2039static int __ovs_ct_limit_get_zone_limit(struct net *net,
2040 struct nf_conncount_data *data,
2041 u16 zone_id, u32 limit,
2042 struct sk_buff *reply)
2043{
2044 struct nf_conntrack_zone ct_zone;
2045 struct ovs_zone_limit zone_limit;
2046 u32 conncount_key = zone_id;
2047
2048 zone_limit.zone_id = zone_id;
2049 zone_limit.limit = limit;
2050 nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0);
2051
2052 zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL,
2053 &ct_zone);
2054 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2055}
2056
2057static int ovs_ct_limit_get_zone_limit(struct net *net,
2058 struct nlattr *nla_zone_limit,
2059 struct ovs_ct_limit_info *info,
2060 struct sk_buff *reply)
2061{
2062 struct ovs_zone_limit *zone_limit;
2063 int rem, err;
2064 u32 limit;
2065 u16 zone;
2066
2067 rem = NLA_ALIGN(nla_len(nla_zone_limit));
2068 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
2069
2070 while (rem >= sizeof(*zone_limit)) {
2071 if (unlikely(zone_limit->zone_id ==
2072 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
2073 err = ovs_ct_limit_get_default_limit(info, reply);
2074 if (err)
2075 return err;
2076 } else if (unlikely(!check_zone_id(zone_limit->zone_id,
2077 &zone))) {
2078 OVS_NLERR(true, "zone id is out of range");
2079 } else {
2080 rcu_read_lock();
2081 limit = ct_limit_get(info, zone);
2082 rcu_read_unlock();
2083
2084 err = __ovs_ct_limit_get_zone_limit(
2085 net, info->data, zone, limit, reply);
2086 if (err)
2087 return err;
2088 }
2089 rem -= NLA_ALIGN(sizeof(*zone_limit));
2090 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2091 NLA_ALIGN(sizeof(*zone_limit)));
2092 }
2093
2094 if (rem)
2095 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem);
2096
2097 return 0;
2098}
2099
2100static int ovs_ct_limit_get_all_zone_limit(struct net *net,
2101 struct ovs_ct_limit_info *info,
2102 struct sk_buff *reply)
2103{
2104 struct ovs_ct_limit *ct_limit;
2105 struct hlist_head *head;
2106 int i, err = 0;
2107
2108 err = ovs_ct_limit_get_default_limit(info, reply);
2109 if (err)
2110 return err;
2111
2112 rcu_read_lock();
2113 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
2114 head = &info->limits[i];
2115 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
2116 err = __ovs_ct_limit_get_zone_limit(net, info->data,
2117 ct_limit->zone, ct_limit->limit, reply);
2118 if (err)
2119 goto exit_err;
2120 }
2121 }
2122
2123exit_err:
2124 rcu_read_unlock();
2125 return err;
2126}
2127
2128static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info)
2129{
2130 struct nlattr **a = info->attrs;
2131 struct sk_buff *reply;
2132 struct ovs_header *ovs_reply_header;
2133 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2134 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2135 int err;
2136
2137 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET,
2138 &ovs_reply_header);
2139 if (IS_ERR(reply))
2140 return PTR_ERR(reply);
2141
2142 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2143 err = -EINVAL;
2144 goto exit_err;
2145 }
2146
2147 err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2148 ct_limit_info);
2149 if (err)
2150 goto exit_err;
2151
2152 static_branch_enable(&ovs_ct_limit_enabled);
2153
2154 genlmsg_end(reply, ovs_reply_header);
2155 return genlmsg_reply(reply, info);
2156
2157exit_err:
2158 nlmsg_free(reply);
2159 return err;
2160}
2161
2162static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info)
2163{
2164 struct nlattr **a = info->attrs;
2165 struct sk_buff *reply;
2166 struct ovs_header *ovs_reply_header;
2167 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2168 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2169 int err;
2170
2171 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL,
2172 &ovs_reply_header);
2173 if (IS_ERR(reply))
2174 return PTR_ERR(reply);
2175
2176 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2177 err = -EINVAL;
2178 goto exit_err;
2179 }
2180
2181 err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2182 ct_limit_info);
2183 if (err)
2184 goto exit_err;
2185
2186 genlmsg_end(reply, ovs_reply_header);
2187 return genlmsg_reply(reply, info);
2188
2189exit_err:
2190 nlmsg_free(reply);
2191 return err;
2192}
2193
2194static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info)
2195{
2196 struct nlattr **a = info->attrs;
2197 struct nlattr *nla_reply;
2198 struct sk_buff *reply;
2199 struct ovs_header *ovs_reply_header;
2200 struct net *net = sock_net(skb->sk);
2201 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2202 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2203 int err;
2204
2205 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET,
2206 &ovs_reply_header);
2207 if (IS_ERR(reply))
2208 return PTR_ERR(reply);
2209
2210 nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT);
2211 if (!nla_reply) {
2212 err = -EMSGSIZE;
2213 goto exit_err;
2214 }
2215
2216 if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2217 err = ovs_ct_limit_get_zone_limit(
2218 net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info,
2219 reply);
2220 if (err)
2221 goto exit_err;
2222 } else {
2223 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info,
2224 reply);
2225 if (err)
2226 goto exit_err;
2227 }
2228
2229 nla_nest_end(reply, nla_reply);
2230 genlmsg_end(reply, ovs_reply_header);
2231 return genlmsg_reply(reply, info);
2232
2233exit_err:
2234 nlmsg_free(reply);
2235 return err;
2236}
2237
2238static struct genl_ops ct_limit_genl_ops[] = {
2239 { .cmd = OVS_CT_LIMIT_CMD_SET,
2240 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2241 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2242 * privilege. */
2243 .doit = ovs_ct_limit_cmd_set,
2244 },
2245 { .cmd = OVS_CT_LIMIT_CMD_DEL,
2246 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2247 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2248 * privilege. */
2249 .doit = ovs_ct_limit_cmd_del,
2250 },
2251 { .cmd = OVS_CT_LIMIT_CMD_GET,
2252 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2253 .flags = 0, /* OK for unprivileged users. */
2254 .doit = ovs_ct_limit_cmd_get,
2255 },
2256};
2257
2258static const struct genl_multicast_group ovs_ct_limit_multicast_group = {
2259 .name = OVS_CT_LIMIT_MCGROUP,
2260};
2261
2262struct genl_family dp_ct_limit_genl_family __ro_after_init = {
2263 .hdrsize = sizeof(struct ovs_header),
2264 .name = OVS_CT_LIMIT_FAMILY,
2265 .version = OVS_CT_LIMIT_VERSION,
2266 .maxattr = OVS_CT_LIMIT_ATTR_MAX,
2267 .policy = ct_limit_policy,
2268 .netnsok = true,
2269 .parallel_ops = true,
2270 .ops = ct_limit_genl_ops,
2271 .n_ops = ARRAY_SIZE(ct_limit_genl_ops),
2272 .mcgrps = &ovs_ct_limit_multicast_group,
2273 .n_mcgrps = 1,
2274 .module = THIS_MODULE,
2275};
2276#endif
2277
2278int ovs_ct_init(struct net *net)
2279{
2280 unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE;
2281 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2282
2283 if (nf_connlabels_get(net, n_bits - 1)) {
2284 ovs_net->xt_label = false;
2285 OVS_NLERR(true, "Failed to set connlabel length");
2286 } else {
2287 ovs_net->xt_label = true;
2288 }
2289
2290#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2291 return ovs_ct_limit_init(net, ovs_net);
2292#else
2293 return 0;
2294#endif
2295}
2296
2297void ovs_ct_exit(struct net *net)
2298{
2299 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2300
2301#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2302 ovs_ct_limit_exit(net, ovs_net);
2303#endif
2304
2305 if (ovs_net->xt_label)
2306 nf_connlabels_put(net);
2307}