Loading...
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
279#define IN6_ADDR_INITIALIZER(ADDR) \
280 { (ADDR).s6_addr32[0], (ADDR).s6_addr32[1], \
281 (ADDR).s6_addr32[2], (ADDR).s6_addr32[3] }
282
283int ovs_ct_put_key(const struct sw_flow_key *swkey,
284 const struct sw_flow_key *output, struct sk_buff *skb)
285{
286 if (nla_put_u32(skb, OVS_KEY_ATTR_CT_STATE, output->ct_state))
287 return -EMSGSIZE;
288
289 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
290 nla_put_u16(skb, OVS_KEY_ATTR_CT_ZONE, output->ct_zone))
291 return -EMSGSIZE;
292
293 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
294 nla_put_u32(skb, OVS_KEY_ATTR_CT_MARK, output->ct.mark))
295 return -EMSGSIZE;
296
297 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
298 nla_put(skb, OVS_KEY_ATTR_CT_LABELS, sizeof(output->ct.labels),
299 &output->ct.labels))
300 return -EMSGSIZE;
301
302 if (swkey->ct_orig_proto) {
303 if (swkey->eth.type == htons(ETH_P_IP)) {
304 struct ovs_key_ct_tuple_ipv4 orig = {
305 output->ipv4.ct_orig.src,
306 output->ipv4.ct_orig.dst,
307 output->ct.orig_tp.src,
308 output->ct.orig_tp.dst,
309 output->ct_orig_proto,
310 };
311 if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV4,
312 sizeof(orig), &orig))
313 return -EMSGSIZE;
314 } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
315 struct ovs_key_ct_tuple_ipv6 orig = {
316 IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.src),
317 IN6_ADDR_INITIALIZER(output->ipv6.ct_orig.dst),
318 output->ct.orig_tp.src,
319 output->ct.orig_tp.dst,
320 output->ct_orig_proto,
321 };
322 if (nla_put(skb, OVS_KEY_ATTR_CT_ORIG_TUPLE_IPV6,
323 sizeof(orig), &orig))
324 return -EMSGSIZE;
325 }
326 }
327
328 return 0;
329}
330
331static int ovs_ct_set_mark(struct nf_conn *ct, struct sw_flow_key *key,
332 u32 ct_mark, u32 mask)
333{
334#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
335 u32 new_mark;
336
337 new_mark = ct_mark | (ct->mark & ~(mask));
338 if (ct->mark != new_mark) {
339 ct->mark = new_mark;
340 if (nf_ct_is_confirmed(ct))
341 nf_conntrack_event_cache(IPCT_MARK, ct);
342 key->ct.mark = new_mark;
343 }
344
345 return 0;
346#else
347 return -ENOTSUPP;
348#endif
349}
350
351static struct nf_conn_labels *ovs_ct_get_conn_labels(struct nf_conn *ct)
352{
353 struct nf_conn_labels *cl;
354
355 cl = nf_ct_labels_find(ct);
356 if (!cl) {
357 nf_ct_labels_ext_add(ct);
358 cl = nf_ct_labels_find(ct);
359 }
360
361 return cl;
362}
363
364/* Initialize labels for a new, yet to be committed conntrack entry. Note that
365 * since the new connection is not yet confirmed, and thus no-one else has
366 * access to it's labels, we simply write them over.
367 */
368static int ovs_ct_init_labels(struct nf_conn *ct, struct sw_flow_key *key,
369 const struct ovs_key_ct_labels *labels,
370 const struct ovs_key_ct_labels *mask)
371{
372 struct nf_conn_labels *cl, *master_cl;
373 bool have_mask = labels_nonzero(mask);
374
375 /* Inherit master's labels to the related connection? */
376 master_cl = ct->master ? nf_ct_labels_find(ct->master) : NULL;
377
378 if (!master_cl && !have_mask)
379 return 0; /* Nothing to do. */
380
381 cl = ovs_ct_get_conn_labels(ct);
382 if (!cl)
383 return -ENOSPC;
384
385 /* Inherit the master's labels, if any. */
386 if (master_cl)
387 *cl = *master_cl;
388
389 if (have_mask) {
390 u32 *dst = (u32 *)cl->bits;
391 int i;
392
393 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
394 dst[i] = (dst[i] & ~mask->ct_labels_32[i]) |
395 (labels->ct_labels_32[i]
396 & mask->ct_labels_32[i]);
397 }
398
399 /* Labels are included in the IPCTNL_MSG_CT_NEW event only if the
400 * IPCT_LABEL bit is set in the event cache.
401 */
402 nf_conntrack_event_cache(IPCT_LABEL, ct);
403
404 memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN);
405
406 return 0;
407}
408
409static int ovs_ct_set_labels(struct nf_conn *ct, struct sw_flow_key *key,
410 const struct ovs_key_ct_labels *labels,
411 const struct ovs_key_ct_labels *mask)
412{
413 struct nf_conn_labels *cl;
414 int err;
415
416 cl = ovs_ct_get_conn_labels(ct);
417 if (!cl)
418 return -ENOSPC;
419
420 err = nf_connlabels_replace(ct, labels->ct_labels_32,
421 mask->ct_labels_32,
422 OVS_CT_LABELS_LEN_32);
423 if (err)
424 return err;
425
426 memcpy(&key->ct.labels, cl->bits, OVS_CT_LABELS_LEN);
427
428 return 0;
429}
430
431/* 'skb' should already be pulled to nh_ofs. */
432static int ovs_ct_helper(struct sk_buff *skb, u16 proto)
433{
434 const struct nf_conntrack_helper *helper;
435 const struct nf_conn_help *help;
436 enum ip_conntrack_info ctinfo;
437 unsigned int protoff;
438 struct nf_conn *ct;
439 int err;
440
441 ct = nf_ct_get(skb, &ctinfo);
442 if (!ct || ctinfo == IP_CT_RELATED_REPLY)
443 return NF_ACCEPT;
444
445 help = nfct_help(ct);
446 if (!help)
447 return NF_ACCEPT;
448
449 helper = rcu_dereference(help->helper);
450 if (!helper)
451 return NF_ACCEPT;
452
453 switch (proto) {
454 case NFPROTO_IPV4:
455 protoff = ip_hdrlen(skb);
456 break;
457 case NFPROTO_IPV6: {
458 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
459 __be16 frag_off;
460 int ofs;
461
462 ofs = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
463 &frag_off);
464 if (ofs < 0 || (frag_off & htons(~0x7)) != 0) {
465 pr_debug("proto header not found\n");
466 return NF_ACCEPT;
467 }
468 protoff = ofs;
469 break;
470 }
471 default:
472 WARN_ONCE(1, "helper invoked on non-IP family!");
473 return NF_DROP;
474 }
475
476 err = helper->help(skb, protoff, ct, ctinfo);
477 if (err != NF_ACCEPT)
478 return err;
479
480 /* Adjust seqs after helper. This is needed due to some helpers (e.g.,
481 * FTP with NAT) adusting the TCP payload size when mangling IP
482 * addresses and/or port numbers in the text-based control connection.
483 */
484 if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
485 !nf_ct_seq_adjust(skb, ct, ctinfo, protoff))
486 return NF_DROP;
487 return NF_ACCEPT;
488}
489
490/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
491 * value if 'skb' is freed.
492 */
493static int handle_fragments(struct net *net, struct sw_flow_key *key,
494 u16 zone, struct sk_buff *skb)
495{
496 struct ovs_skb_cb ovs_cb = *OVS_CB(skb);
497 int err;
498
499 if (key->eth.type == htons(ETH_P_IP)) {
500 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
501
502 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
503 err = ip_defrag(net, skb, user);
504 if (err)
505 return err;
506
507 ovs_cb.mru = IPCB(skb)->frag_max_size;
508#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
509 } else if (key->eth.type == htons(ETH_P_IPV6)) {
510 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
511
512 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
513 err = nf_ct_frag6_gather(net, skb, user);
514 if (err) {
515 if (err != -EINPROGRESS)
516 kfree_skb(skb);
517 return err;
518 }
519
520 key->ip.proto = ipv6_hdr(skb)->nexthdr;
521 ovs_cb.mru = IP6CB(skb)->frag_max_size;
522#endif
523 } else {
524 kfree_skb(skb);
525 return -EPFNOSUPPORT;
526 }
527
528 /* The key extracted from the fragment that completed this datagram
529 * likely didn't have an L4 header, so regenerate it.
530 */
531 ovs_flow_key_update_l3l4(skb, key);
532
533 key->ip.frag = OVS_FRAG_TYPE_NONE;
534 skb_clear_hash(skb);
535 skb->ignore_df = 1;
536 *OVS_CB(skb) = ovs_cb;
537
538 return 0;
539}
540
541static struct nf_conntrack_expect *
542ovs_ct_expect_find(struct net *net, const struct nf_conntrack_zone *zone,
543 u16 proto, const struct sk_buff *skb)
544{
545 struct nf_conntrack_tuple tuple;
546 struct nf_conntrack_expect *exp;
547
548 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), proto, net, &tuple))
549 return NULL;
550
551 exp = __nf_ct_expect_find(net, zone, &tuple);
552 if (exp) {
553 struct nf_conntrack_tuple_hash *h;
554
555 /* Delete existing conntrack entry, if it clashes with the
556 * expectation. This can happen since conntrack ALGs do not
557 * check for clashes between (new) expectations and existing
558 * conntrack entries. nf_conntrack_in() will check the
559 * expectations only if a conntrack entry can not be found,
560 * which can lead to OVS finding the expectation (here) in the
561 * init direction, but which will not be removed by the
562 * nf_conntrack_in() call, if a matching conntrack entry is
563 * found instead. In this case all init direction packets
564 * would be reported as new related packets, while reply
565 * direction packets would be reported as un-related
566 * established packets.
567 */
568 h = nf_conntrack_find_get(net, zone, &tuple);
569 if (h) {
570 struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
571
572 nf_ct_delete(ct, 0, 0);
573 nf_conntrack_put(&ct->ct_general);
574 }
575 }
576
577 return exp;
578}
579
580/* This replicates logic from nf_conntrack_core.c that is not exported. */
581static enum ip_conntrack_info
582ovs_ct_get_info(const struct nf_conntrack_tuple_hash *h)
583{
584 const struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
585
586 if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
587 return IP_CT_ESTABLISHED_REPLY;
588 /* Once we've had two way comms, always ESTABLISHED. */
589 if (test_bit(IPS_SEEN_REPLY_BIT, &ct->status))
590 return IP_CT_ESTABLISHED;
591 if (test_bit(IPS_EXPECTED_BIT, &ct->status))
592 return IP_CT_RELATED;
593 return IP_CT_NEW;
594}
595
596/* Find an existing connection which this packet belongs to without
597 * re-attributing statistics or modifying the connection state. This allows an
598 * skb->_nfct lost due to an upcall to be recovered during actions execution.
599 *
600 * Must be called with rcu_read_lock.
601 *
602 * On success, populates skb->_nfct and returns the connection. Returns NULL
603 * if there is no existing entry.
604 */
605static struct nf_conn *
606ovs_ct_find_existing(struct net *net, const struct nf_conntrack_zone *zone,
607 u8 l3num, struct sk_buff *skb, bool natted)
608{
609 struct nf_conntrack_tuple tuple;
610 struct nf_conntrack_tuple_hash *h;
611 struct nf_conn *ct;
612
613 if (!nf_ct_get_tuplepr(skb, skb_network_offset(skb), l3num,
614 net, &tuple)) {
615 pr_debug("ovs_ct_find_existing: Can't get tuple\n");
616 return NULL;
617 }
618
619 /* Must invert the tuple if skb has been transformed by NAT. */
620 if (natted) {
621 struct nf_conntrack_tuple inverse;
622
623 if (!nf_ct_invert_tuple(&inverse, &tuple)) {
624 pr_debug("ovs_ct_find_existing: Inversion failed!\n");
625 return NULL;
626 }
627 tuple = inverse;
628 }
629
630 /* look for tuple match */
631 h = nf_conntrack_find_get(net, zone, &tuple);
632 if (!h)
633 return NULL; /* Not found. */
634
635 ct = nf_ct_tuplehash_to_ctrack(h);
636
637 /* Inverted packet tuple matches the reverse direction conntrack tuple,
638 * select the other tuplehash to get the right 'ctinfo' bits for this
639 * packet.
640 */
641 if (natted)
642 h = &ct->tuplehash[!h->tuple.dst.dir];
643
644 nf_ct_set(skb, ct, ovs_ct_get_info(h));
645 return ct;
646}
647
648static
649struct nf_conn *ovs_ct_executed(struct net *net,
650 const struct sw_flow_key *key,
651 const struct ovs_conntrack_info *info,
652 struct sk_buff *skb,
653 bool *ct_executed)
654{
655 struct nf_conn *ct = NULL;
656
657 /* If no ct, check if we have evidence that an existing conntrack entry
658 * might be found for this skb. This happens when we lose a skb->_nfct
659 * due to an upcall, or if the direction is being forced. If the
660 * connection was not confirmed, it is not cached and needs to be run
661 * through conntrack again.
662 */
663 *ct_executed = (key->ct_state & OVS_CS_F_TRACKED) &&
664 !(key->ct_state & OVS_CS_F_INVALID) &&
665 (key->ct_zone == info->zone.id);
666
667 if (*ct_executed || (!key->ct_state && info->force)) {
668 ct = ovs_ct_find_existing(net, &info->zone, info->family, skb,
669 !!(key->ct_state &
670 OVS_CS_F_NAT_MASK));
671 }
672
673 return ct;
674}
675
676/* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
677static bool skb_nfct_cached(struct net *net,
678 const struct sw_flow_key *key,
679 const struct ovs_conntrack_info *info,
680 struct sk_buff *skb)
681{
682 enum ip_conntrack_info ctinfo;
683 struct nf_conn *ct;
684 bool ct_executed = true;
685
686 ct = nf_ct_get(skb, &ctinfo);
687 if (!ct)
688 ct = ovs_ct_executed(net, key, info, skb, &ct_executed);
689
690 if (ct)
691 nf_ct_get(skb, &ctinfo);
692 else
693 return false;
694
695 if (!net_eq(net, read_pnet(&ct->ct_net)))
696 return false;
697 if (!nf_ct_zone_equal_any(info->ct, nf_ct_zone(ct)))
698 return false;
699 if (info->helper) {
700 struct nf_conn_help *help;
701
702 help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
703 if (help && rcu_access_pointer(help->helper) != info->helper)
704 return false;
705 }
706 if (info->nf_ct_timeout) {
707 struct nf_conn_timeout *timeout_ext;
708
709 timeout_ext = nf_ct_timeout_find(ct);
710 if (!timeout_ext || info->nf_ct_timeout !=
711 rcu_dereference(timeout_ext->timeout))
712 return false;
713 }
714 /* Force conntrack entry direction to the current packet? */
715 if (info->force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
716 /* Delete the conntrack entry if confirmed, else just release
717 * the reference.
718 */
719 if (nf_ct_is_confirmed(ct))
720 nf_ct_delete(ct, 0, 0);
721
722 nf_conntrack_put(&ct->ct_general);
723 nf_ct_set(skb, NULL, 0);
724 return false;
725 }
726
727 return ct_executed;
728}
729
730#if IS_ENABLED(CONFIG_NF_NAT)
731/* Modelled after nf_nat_ipv[46]_fn().
732 * range is only used for new, uninitialized NAT state.
733 * Returns either NF_ACCEPT or NF_DROP.
734 */
735static int ovs_ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
736 enum ip_conntrack_info ctinfo,
737 const struct nf_nat_range2 *range,
738 enum nf_nat_manip_type maniptype)
739{
740 int hooknum, nh_off, err = NF_ACCEPT;
741
742 nh_off = skb_network_offset(skb);
743 skb_pull_rcsum(skb, nh_off);
744
745 /* See HOOK2MANIP(). */
746 if (maniptype == NF_NAT_MANIP_SRC)
747 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
748 else
749 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
750
751 switch (ctinfo) {
752 case IP_CT_RELATED:
753 case IP_CT_RELATED_REPLY:
754 if (IS_ENABLED(CONFIG_NF_NAT) &&
755 skb->protocol == htons(ETH_P_IP) &&
756 ip_hdr(skb)->protocol == IPPROTO_ICMP) {
757 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
758 hooknum))
759 err = NF_DROP;
760 goto push;
761 } else if (IS_ENABLED(CONFIG_IPV6) &&
762 skb->protocol == htons(ETH_P_IPV6)) {
763 __be16 frag_off;
764 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
765 int hdrlen = ipv6_skip_exthdr(skb,
766 sizeof(struct ipv6hdr),
767 &nexthdr, &frag_off);
768
769 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
770 if (!nf_nat_icmpv6_reply_translation(skb, ct,
771 ctinfo,
772 hooknum,
773 hdrlen))
774 err = NF_DROP;
775 goto push;
776 }
777 }
778 /* Non-ICMP, fall thru to initialize if needed. */
779 /* fall through */
780 case IP_CT_NEW:
781 /* Seen it before? This can happen for loopback, retrans,
782 * or local packets.
783 */
784 if (!nf_nat_initialized(ct, maniptype)) {
785 /* Initialize according to the NAT action. */
786 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
787 /* Action is set up to establish a new
788 * mapping.
789 */
790 ? nf_nat_setup_info(ct, range, maniptype)
791 : nf_nat_alloc_null_binding(ct, hooknum);
792 if (err != NF_ACCEPT)
793 goto push;
794 }
795 break;
796
797 case IP_CT_ESTABLISHED:
798 case IP_CT_ESTABLISHED_REPLY:
799 break;
800
801 default:
802 err = NF_DROP;
803 goto push;
804 }
805
806 err = nf_nat_packet(ct, ctinfo, hooknum, skb);
807push:
808 skb_push(skb, nh_off);
809 skb_postpush_rcsum(skb, skb->data, nh_off);
810
811 return err;
812}
813
814static void ovs_nat_update_key(struct sw_flow_key *key,
815 const struct sk_buff *skb,
816 enum nf_nat_manip_type maniptype)
817{
818 if (maniptype == NF_NAT_MANIP_SRC) {
819 __be16 src;
820
821 key->ct_state |= OVS_CS_F_SRC_NAT;
822 if (key->eth.type == htons(ETH_P_IP))
823 key->ipv4.addr.src = ip_hdr(skb)->saddr;
824 else if (key->eth.type == htons(ETH_P_IPV6))
825 memcpy(&key->ipv6.addr.src, &ipv6_hdr(skb)->saddr,
826 sizeof(key->ipv6.addr.src));
827 else
828 return;
829
830 if (key->ip.proto == IPPROTO_UDP)
831 src = udp_hdr(skb)->source;
832 else if (key->ip.proto == IPPROTO_TCP)
833 src = tcp_hdr(skb)->source;
834 else if (key->ip.proto == IPPROTO_SCTP)
835 src = sctp_hdr(skb)->source;
836 else
837 return;
838
839 key->tp.src = src;
840 } else {
841 __be16 dst;
842
843 key->ct_state |= OVS_CS_F_DST_NAT;
844 if (key->eth.type == htons(ETH_P_IP))
845 key->ipv4.addr.dst = ip_hdr(skb)->daddr;
846 else if (key->eth.type == htons(ETH_P_IPV6))
847 memcpy(&key->ipv6.addr.dst, &ipv6_hdr(skb)->daddr,
848 sizeof(key->ipv6.addr.dst));
849 else
850 return;
851
852 if (key->ip.proto == IPPROTO_UDP)
853 dst = udp_hdr(skb)->dest;
854 else if (key->ip.proto == IPPROTO_TCP)
855 dst = tcp_hdr(skb)->dest;
856 else if (key->ip.proto == IPPROTO_SCTP)
857 dst = sctp_hdr(skb)->dest;
858 else
859 return;
860
861 key->tp.dst = dst;
862 }
863}
864
865/* Returns NF_DROP if the packet should be dropped, NF_ACCEPT otherwise. */
866static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
867 const struct ovs_conntrack_info *info,
868 struct sk_buff *skb, struct nf_conn *ct,
869 enum ip_conntrack_info ctinfo)
870{
871 enum nf_nat_manip_type maniptype;
872 int err;
873
874 /* Add NAT extension if not confirmed yet. */
875 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
876 return NF_ACCEPT; /* Can't NAT. */
877
878 /* Determine NAT type.
879 * Check if the NAT type can be deduced from the tracked connection.
880 * Make sure new expected connections (IP_CT_RELATED) are NATted only
881 * when committing.
882 */
883 if (info->nat & OVS_CT_NAT && ctinfo != IP_CT_NEW &&
884 ct->status & IPS_NAT_MASK &&
885 (ctinfo != IP_CT_RELATED || info->commit)) {
886 /* NAT an established or related connection like before. */
887 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
888 /* This is the REPLY direction for a connection
889 * for which NAT was applied in the forward
890 * direction. Do the reverse NAT.
891 */
892 maniptype = ct->status & IPS_SRC_NAT
893 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
894 else
895 maniptype = ct->status & IPS_SRC_NAT
896 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
897 } else if (info->nat & OVS_CT_SRC_NAT) {
898 maniptype = NF_NAT_MANIP_SRC;
899 } else if (info->nat & OVS_CT_DST_NAT) {
900 maniptype = NF_NAT_MANIP_DST;
901 } else {
902 return NF_ACCEPT; /* Connection is not NATed. */
903 }
904 err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype);
905
906 /* Mark NAT done if successful and update the flow key. */
907 if (err == NF_ACCEPT)
908 ovs_nat_update_key(key, skb, maniptype);
909
910 return err;
911}
912#else /* !CONFIG_NF_NAT */
913static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
914 const struct ovs_conntrack_info *info,
915 struct sk_buff *skb, struct nf_conn *ct,
916 enum ip_conntrack_info ctinfo)
917{
918 return NF_ACCEPT;
919}
920#endif
921
922/* Pass 'skb' through conntrack in 'net', using zone configured in 'info', if
923 * not done already. Update key with new CT state after passing the packet
924 * through conntrack.
925 * Note that if the packet is deemed invalid by conntrack, skb->_nfct will be
926 * set to NULL and 0 will be returned.
927 */
928static int __ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
929 const struct ovs_conntrack_info *info,
930 struct sk_buff *skb)
931{
932 /* If we are recirculating packets to match on conntrack fields and
933 * committing with a separate conntrack action, then we don't need to
934 * actually run the packet through conntrack twice unless it's for a
935 * different zone.
936 */
937 bool cached = skb_nfct_cached(net, key, info, skb);
938 enum ip_conntrack_info ctinfo;
939 struct nf_conn *ct;
940
941 if (!cached) {
942 struct nf_hook_state state = {
943 .hook = NF_INET_PRE_ROUTING,
944 .pf = info->family,
945 .net = net,
946 };
947 struct nf_conn *tmpl = info->ct;
948 int err;
949
950 /* Associate skb with specified zone. */
951 if (tmpl) {
952 if (skb_nfct(skb))
953 nf_conntrack_put(skb_nfct(skb));
954 nf_conntrack_get(&tmpl->ct_general);
955 nf_ct_set(skb, tmpl, IP_CT_NEW);
956 }
957
958 err = nf_conntrack_in(skb, &state);
959 if (err != NF_ACCEPT)
960 return -ENOENT;
961
962 /* Clear CT state NAT flags to mark that we have not yet done
963 * NAT after the nf_conntrack_in() call. We can actually clear
964 * the whole state, as it will be re-initialized below.
965 */
966 key->ct_state = 0;
967
968 /* Update the key, but keep the NAT flags. */
969 ovs_ct_update_key(skb, info, key, true, true);
970 }
971
972 ct = nf_ct_get(skb, &ctinfo);
973 if (ct) {
974 /* Packets starting a new connection must be NATted before the
975 * helper, so that the helper knows about the NAT. We enforce
976 * this by delaying both NAT and helper calls for unconfirmed
977 * connections until the committing CT action. For later
978 * packets NAT and Helper may be called in either order.
979 *
980 * NAT will be done only if the CT action has NAT, and only
981 * once per packet (per zone), as guarded by the NAT bits in
982 * the key->ct_state.
983 */
984 if (info->nat && !(key->ct_state & OVS_CS_F_NAT_MASK) &&
985 (nf_ct_is_confirmed(ct) || info->commit) &&
986 ovs_ct_nat(net, key, info, skb, ct, ctinfo) != NF_ACCEPT) {
987 return -EINVAL;
988 }
989
990 /* Userspace may decide to perform a ct lookup without a helper
991 * specified followed by a (recirculate and) commit with one.
992 * Therefore, for unconfirmed connections which we will commit,
993 * we need to attach the helper here.
994 */
995 if (!nf_ct_is_confirmed(ct) && info->commit &&
996 info->helper && !nfct_help(ct)) {
997 int err = __nf_ct_try_assign_helper(ct, info->ct,
998 GFP_ATOMIC);
999 if (err)
1000 return err;
1001
1002 /* helper installed, add seqadj if NAT is required */
1003 if (info->nat && !nfct_seqadj(ct)) {
1004 if (!nfct_seqadj_ext_add(ct))
1005 return -EINVAL;
1006 }
1007 }
1008
1009 /* Call the helper only if:
1010 * - nf_conntrack_in() was executed above ("!cached") for a
1011 * confirmed connection, or
1012 * - When committing an unconfirmed connection.
1013 */
1014 if ((nf_ct_is_confirmed(ct) ? !cached : info->commit) &&
1015 ovs_ct_helper(skb, info->family) != NF_ACCEPT) {
1016 return -EINVAL;
1017 }
1018 }
1019
1020 return 0;
1021}
1022
1023/* Lookup connection and read fields into key. */
1024static int ovs_ct_lookup(struct net *net, struct sw_flow_key *key,
1025 const struct ovs_conntrack_info *info,
1026 struct sk_buff *skb)
1027{
1028 struct nf_conntrack_expect *exp;
1029
1030 /* If we pass an expected packet through nf_conntrack_in() the
1031 * expectation is typically removed, but the packet could still be
1032 * lost in upcall processing. To prevent this from happening we
1033 * perform an explicit expectation lookup. Expected connections are
1034 * always new, and will be passed through conntrack only when they are
1035 * committed, as it is OK to remove the expectation at that time.
1036 */
1037 exp = ovs_ct_expect_find(net, &info->zone, info->family, skb);
1038 if (exp) {
1039 u8 state;
1040
1041 /* NOTE: New connections are NATted and Helped only when
1042 * committed, so we are not calling into NAT here.
1043 */
1044 state = OVS_CS_F_TRACKED | OVS_CS_F_NEW | OVS_CS_F_RELATED;
1045 __ovs_ct_update_key(key, state, &info->zone, exp->master);
1046 } else {
1047 struct nf_conn *ct;
1048 int err;
1049
1050 err = __ovs_ct_lookup(net, key, info, skb);
1051 if (err)
1052 return err;
1053
1054 ct = (struct nf_conn *)skb_nfct(skb);
1055 if (ct)
1056 nf_ct_deliver_cached_events(ct);
1057 }
1058
1059 return 0;
1060}
1061
1062static bool labels_nonzero(const struct ovs_key_ct_labels *labels)
1063{
1064 size_t i;
1065
1066 for (i = 0; i < OVS_CT_LABELS_LEN_32; i++)
1067 if (labels->ct_labels_32[i])
1068 return true;
1069
1070 return false;
1071}
1072
1073#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1074static struct hlist_head *ct_limit_hash_bucket(
1075 const struct ovs_ct_limit_info *info, u16 zone)
1076{
1077 return &info->limits[zone & (CT_LIMIT_HASH_BUCKETS - 1)];
1078}
1079
1080/* Call with ovs_mutex */
1081static void ct_limit_set(const struct ovs_ct_limit_info *info,
1082 struct ovs_ct_limit *new_ct_limit)
1083{
1084 struct ovs_ct_limit *ct_limit;
1085 struct hlist_head *head;
1086
1087 head = ct_limit_hash_bucket(info, new_ct_limit->zone);
1088 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1089 if (ct_limit->zone == new_ct_limit->zone) {
1090 hlist_replace_rcu(&ct_limit->hlist_node,
1091 &new_ct_limit->hlist_node);
1092 kfree_rcu(ct_limit, rcu);
1093 return;
1094 }
1095 }
1096
1097 hlist_add_head_rcu(&new_ct_limit->hlist_node, head);
1098}
1099
1100/* Call with ovs_mutex */
1101static void ct_limit_del(const struct ovs_ct_limit_info *info, u16 zone)
1102{
1103 struct ovs_ct_limit *ct_limit;
1104 struct hlist_head *head;
1105 struct hlist_node *n;
1106
1107 head = ct_limit_hash_bucket(info, zone);
1108 hlist_for_each_entry_safe(ct_limit, n, head, hlist_node) {
1109 if (ct_limit->zone == zone) {
1110 hlist_del_rcu(&ct_limit->hlist_node);
1111 kfree_rcu(ct_limit, rcu);
1112 return;
1113 }
1114 }
1115}
1116
1117/* Call with RCU read lock */
1118static u32 ct_limit_get(const struct ovs_ct_limit_info *info, u16 zone)
1119{
1120 struct ovs_ct_limit *ct_limit;
1121 struct hlist_head *head;
1122
1123 head = ct_limit_hash_bucket(info, zone);
1124 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
1125 if (ct_limit->zone == zone)
1126 return ct_limit->limit;
1127 }
1128
1129 return info->default_limit;
1130}
1131
1132static int ovs_ct_check_limit(struct net *net,
1133 const struct ovs_conntrack_info *info,
1134 const struct nf_conntrack_tuple *tuple)
1135{
1136 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1137 const struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
1138 u32 per_zone_limit, connections;
1139 u32 conncount_key;
1140
1141 conncount_key = info->zone.id;
1142
1143 per_zone_limit = ct_limit_get(ct_limit_info, info->zone.id);
1144 if (per_zone_limit == OVS_CT_LIMIT_UNLIMITED)
1145 return 0;
1146
1147 connections = nf_conncount_count(net, ct_limit_info->data,
1148 &conncount_key, tuple, &info->zone);
1149 if (connections > per_zone_limit)
1150 return -ENOMEM;
1151
1152 return 0;
1153}
1154#endif
1155
1156/* Lookup connection and confirm if unconfirmed. */
1157static int ovs_ct_commit(struct net *net, struct sw_flow_key *key,
1158 const struct ovs_conntrack_info *info,
1159 struct sk_buff *skb)
1160{
1161 enum ip_conntrack_info ctinfo;
1162 struct nf_conn *ct;
1163 int err;
1164
1165 err = __ovs_ct_lookup(net, key, info, skb);
1166 if (err)
1167 return err;
1168
1169 /* The connection could be invalid, in which case this is a no-op.*/
1170 ct = nf_ct_get(skb, &ctinfo);
1171 if (!ct)
1172 return 0;
1173
1174#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1175 if (static_branch_unlikely(&ovs_ct_limit_enabled)) {
1176 if (!nf_ct_is_confirmed(ct)) {
1177 err = ovs_ct_check_limit(net, info,
1178 &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple);
1179 if (err) {
1180 net_warn_ratelimited("openvswitch: zone: %u "
1181 "exceeds conntrack limit\n",
1182 info->zone.id);
1183 return err;
1184 }
1185 }
1186 }
1187#endif
1188
1189 /* Set the conntrack event mask if given. NEW and DELETE events have
1190 * their own groups, but the NFNLGRP_CONNTRACK_UPDATE group listener
1191 * typically would receive many kinds of updates. Setting the event
1192 * mask allows those events to be filtered. The set event mask will
1193 * remain in effect for the lifetime of the connection unless changed
1194 * by a further CT action with both the commit flag and the eventmask
1195 * option. */
1196 if (info->have_eventmask) {
1197 struct nf_conntrack_ecache *cache = nf_ct_ecache_find(ct);
1198
1199 if (cache)
1200 cache->ctmask = info->eventmask;
1201 }
1202
1203 /* Apply changes before confirming the connection so that the initial
1204 * conntrack NEW netlink event carries the values given in the CT
1205 * action.
1206 */
1207 if (info->mark.mask) {
1208 err = ovs_ct_set_mark(ct, key, info->mark.value,
1209 info->mark.mask);
1210 if (err)
1211 return err;
1212 }
1213 if (!nf_ct_is_confirmed(ct)) {
1214 err = ovs_ct_init_labels(ct, key, &info->labels.value,
1215 &info->labels.mask);
1216 if (err)
1217 return err;
1218 } else if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1219 labels_nonzero(&info->labels.mask)) {
1220 err = ovs_ct_set_labels(ct, key, &info->labels.value,
1221 &info->labels.mask);
1222 if (err)
1223 return err;
1224 }
1225 /* This will take care of sending queued events even if the connection
1226 * is already confirmed.
1227 */
1228 if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1229 return -EINVAL;
1230
1231 return 0;
1232}
1233
1234/* Trim the skb to the length specified by the IP/IPv6 header,
1235 * removing any trailing lower-layer padding. This prepares the skb
1236 * for higher-layer processing that assumes skb->len excludes padding
1237 * (such as nf_ip_checksum). The caller needs to pull the skb to the
1238 * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
1239 */
1240static int ovs_skb_network_trim(struct sk_buff *skb)
1241{
1242 unsigned int len;
1243 int err;
1244
1245 switch (skb->protocol) {
1246 case htons(ETH_P_IP):
1247 len = ntohs(ip_hdr(skb)->tot_len);
1248 break;
1249 case htons(ETH_P_IPV6):
1250 len = sizeof(struct ipv6hdr)
1251 + ntohs(ipv6_hdr(skb)->payload_len);
1252 break;
1253 default:
1254 len = skb->len;
1255 }
1256
1257 err = pskb_trim_rcsum(skb, len);
1258 if (err)
1259 kfree_skb(skb);
1260
1261 return err;
1262}
1263
1264/* Returns 0 on success, -EINPROGRESS if 'skb' is stolen, or other nonzero
1265 * value if 'skb' is freed.
1266 */
1267int ovs_ct_execute(struct net *net, struct sk_buff *skb,
1268 struct sw_flow_key *key,
1269 const struct ovs_conntrack_info *info)
1270{
1271 int nh_ofs;
1272 int err;
1273
1274 /* The conntrack module expects to be working at L3. */
1275 nh_ofs = skb_network_offset(skb);
1276 skb_pull_rcsum(skb, nh_ofs);
1277
1278 err = ovs_skb_network_trim(skb);
1279 if (err)
1280 return err;
1281
1282 if (key->ip.frag != OVS_FRAG_TYPE_NONE) {
1283 err = handle_fragments(net, key, info->zone.id, skb);
1284 if (err)
1285 return err;
1286 }
1287
1288 if (info->commit)
1289 err = ovs_ct_commit(net, key, info, skb);
1290 else
1291 err = ovs_ct_lookup(net, key, info, skb);
1292
1293 skb_push(skb, nh_ofs);
1294 skb_postpush_rcsum(skb, skb->data, nh_ofs);
1295 if (err)
1296 kfree_skb(skb);
1297 return err;
1298}
1299
1300int ovs_ct_clear(struct sk_buff *skb, struct sw_flow_key *key)
1301{
1302 if (skb_nfct(skb)) {
1303 nf_conntrack_put(skb_nfct(skb));
1304 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
1305 ovs_ct_fill_key(skb, key);
1306 }
1307
1308 return 0;
1309}
1310
1311static int ovs_ct_add_helper(struct ovs_conntrack_info *info, const char *name,
1312 const struct sw_flow_key *key, bool log)
1313{
1314 struct nf_conntrack_helper *helper;
1315 struct nf_conn_help *help;
1316 int ret = 0;
1317
1318 helper = nf_conntrack_helper_try_module_get(name, info->family,
1319 key->ip.proto);
1320 if (!helper) {
1321 OVS_NLERR(log, "Unknown helper \"%s\"", name);
1322 return -EINVAL;
1323 }
1324
1325 help = nf_ct_helper_ext_add(info->ct, GFP_KERNEL);
1326 if (!help) {
1327 nf_conntrack_helper_put(helper);
1328 return -ENOMEM;
1329 }
1330
1331#if IS_ENABLED(CONFIG_NF_NAT)
1332 if (info->nat) {
1333 ret = nf_nat_helper_try_module_get(name, info->family,
1334 key->ip.proto);
1335 if (ret) {
1336 nf_conntrack_helper_put(helper);
1337 OVS_NLERR(log, "Failed to load \"%s\" NAT helper, error: %d",
1338 name, ret);
1339 return ret;
1340 }
1341 }
1342#endif
1343 rcu_assign_pointer(help->helper, helper);
1344 info->helper = helper;
1345 return ret;
1346}
1347
1348#if IS_ENABLED(CONFIG_NF_NAT)
1349static int parse_nat(const struct nlattr *attr,
1350 struct ovs_conntrack_info *info, bool log)
1351{
1352 struct nlattr *a;
1353 int rem;
1354 bool have_ip_max = false;
1355 bool have_proto_max = false;
1356 bool ip_vers = (info->family == NFPROTO_IPV6);
1357
1358 nla_for_each_nested(a, attr, rem) {
1359 static const int ovs_nat_attr_lens[OVS_NAT_ATTR_MAX + 1][2] = {
1360 [OVS_NAT_ATTR_SRC] = {0, 0},
1361 [OVS_NAT_ATTR_DST] = {0, 0},
1362 [OVS_NAT_ATTR_IP_MIN] = {sizeof(struct in_addr),
1363 sizeof(struct in6_addr)},
1364 [OVS_NAT_ATTR_IP_MAX] = {sizeof(struct in_addr),
1365 sizeof(struct in6_addr)},
1366 [OVS_NAT_ATTR_PROTO_MIN] = {sizeof(u16), sizeof(u16)},
1367 [OVS_NAT_ATTR_PROTO_MAX] = {sizeof(u16), sizeof(u16)},
1368 [OVS_NAT_ATTR_PERSISTENT] = {0, 0},
1369 [OVS_NAT_ATTR_PROTO_HASH] = {0, 0},
1370 [OVS_NAT_ATTR_PROTO_RANDOM] = {0, 0},
1371 };
1372 int type = nla_type(a);
1373
1374 if (type > OVS_NAT_ATTR_MAX) {
1375 OVS_NLERR(log, "Unknown NAT attribute (type=%d, max=%d)",
1376 type, OVS_NAT_ATTR_MAX);
1377 return -EINVAL;
1378 }
1379
1380 if (nla_len(a) != ovs_nat_attr_lens[type][ip_vers]) {
1381 OVS_NLERR(log, "NAT attribute type %d has unexpected length (%d != %d)",
1382 type, nla_len(a),
1383 ovs_nat_attr_lens[type][ip_vers]);
1384 return -EINVAL;
1385 }
1386
1387 switch (type) {
1388 case OVS_NAT_ATTR_SRC:
1389 case OVS_NAT_ATTR_DST:
1390 if (info->nat) {
1391 OVS_NLERR(log, "Only one type of NAT may be specified");
1392 return -ERANGE;
1393 }
1394 info->nat |= OVS_CT_NAT;
1395 info->nat |= ((type == OVS_NAT_ATTR_SRC)
1396 ? OVS_CT_SRC_NAT : OVS_CT_DST_NAT);
1397 break;
1398
1399 case OVS_NAT_ATTR_IP_MIN:
1400 nla_memcpy(&info->range.min_addr, a,
1401 sizeof(info->range.min_addr));
1402 info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1403 break;
1404
1405 case OVS_NAT_ATTR_IP_MAX:
1406 have_ip_max = true;
1407 nla_memcpy(&info->range.max_addr, a,
1408 sizeof(info->range.max_addr));
1409 info->range.flags |= NF_NAT_RANGE_MAP_IPS;
1410 break;
1411
1412 case OVS_NAT_ATTR_PROTO_MIN:
1413 info->range.min_proto.all = htons(nla_get_u16(a));
1414 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1415 break;
1416
1417 case OVS_NAT_ATTR_PROTO_MAX:
1418 have_proto_max = true;
1419 info->range.max_proto.all = htons(nla_get_u16(a));
1420 info->range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1421 break;
1422
1423 case OVS_NAT_ATTR_PERSISTENT:
1424 info->range.flags |= NF_NAT_RANGE_PERSISTENT;
1425 break;
1426
1427 case OVS_NAT_ATTR_PROTO_HASH:
1428 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM;
1429 break;
1430
1431 case OVS_NAT_ATTR_PROTO_RANDOM:
1432 info->range.flags |= NF_NAT_RANGE_PROTO_RANDOM_FULLY;
1433 break;
1434
1435 default:
1436 OVS_NLERR(log, "Unknown nat attribute (%d)", type);
1437 return -EINVAL;
1438 }
1439 }
1440
1441 if (rem > 0) {
1442 OVS_NLERR(log, "NAT attribute has %d unknown bytes", rem);
1443 return -EINVAL;
1444 }
1445 if (!info->nat) {
1446 /* Do not allow flags if no type is given. */
1447 if (info->range.flags) {
1448 OVS_NLERR(log,
1449 "NAT flags may be given only when NAT range (SRC or DST) is also specified."
1450 );
1451 return -EINVAL;
1452 }
1453 info->nat = OVS_CT_NAT; /* NAT existing connections. */
1454 } else if (!info->commit) {
1455 OVS_NLERR(log,
1456 "NAT attributes may be specified only when CT COMMIT flag is also specified."
1457 );
1458 return -EINVAL;
1459 }
1460 /* Allow missing IP_MAX. */
1461 if (info->range.flags & NF_NAT_RANGE_MAP_IPS && !have_ip_max) {
1462 memcpy(&info->range.max_addr, &info->range.min_addr,
1463 sizeof(info->range.max_addr));
1464 }
1465 /* Allow missing PROTO_MAX. */
1466 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1467 !have_proto_max) {
1468 info->range.max_proto.all = info->range.min_proto.all;
1469 }
1470 return 0;
1471}
1472#endif
1473
1474static const struct ovs_ct_len_tbl ovs_ct_attr_lens[OVS_CT_ATTR_MAX + 1] = {
1475 [OVS_CT_ATTR_COMMIT] = { .minlen = 0, .maxlen = 0 },
1476 [OVS_CT_ATTR_FORCE_COMMIT] = { .minlen = 0, .maxlen = 0 },
1477 [OVS_CT_ATTR_ZONE] = { .minlen = sizeof(u16),
1478 .maxlen = sizeof(u16) },
1479 [OVS_CT_ATTR_MARK] = { .minlen = sizeof(struct md_mark),
1480 .maxlen = sizeof(struct md_mark) },
1481 [OVS_CT_ATTR_LABELS] = { .minlen = sizeof(struct md_labels),
1482 .maxlen = sizeof(struct md_labels) },
1483 [OVS_CT_ATTR_HELPER] = { .minlen = 1,
1484 .maxlen = NF_CT_HELPER_NAME_LEN },
1485#if IS_ENABLED(CONFIG_NF_NAT)
1486 /* NAT length is checked when parsing the nested attributes. */
1487 [OVS_CT_ATTR_NAT] = { .minlen = 0, .maxlen = INT_MAX },
1488#endif
1489 [OVS_CT_ATTR_EVENTMASK] = { .minlen = sizeof(u32),
1490 .maxlen = sizeof(u32) },
1491 [OVS_CT_ATTR_TIMEOUT] = { .minlen = 1,
1492 .maxlen = CTNL_TIMEOUT_NAME_MAX },
1493};
1494
1495static int parse_ct(const struct nlattr *attr, struct ovs_conntrack_info *info,
1496 const char **helper, bool log)
1497{
1498 struct nlattr *a;
1499 int rem;
1500
1501 nla_for_each_nested(a, attr, rem) {
1502 int type = nla_type(a);
1503 int maxlen;
1504 int minlen;
1505
1506 if (type > OVS_CT_ATTR_MAX) {
1507 OVS_NLERR(log,
1508 "Unknown conntrack attr (type=%d, max=%d)",
1509 type, OVS_CT_ATTR_MAX);
1510 return -EINVAL;
1511 }
1512
1513 maxlen = ovs_ct_attr_lens[type].maxlen;
1514 minlen = ovs_ct_attr_lens[type].minlen;
1515 if (nla_len(a) < minlen || nla_len(a) > maxlen) {
1516 OVS_NLERR(log,
1517 "Conntrack attr type has unexpected length (type=%d, length=%d, expected=%d)",
1518 type, nla_len(a), maxlen);
1519 return -EINVAL;
1520 }
1521
1522 switch (type) {
1523 case OVS_CT_ATTR_FORCE_COMMIT:
1524 info->force = true;
1525 /* fall through. */
1526 case OVS_CT_ATTR_COMMIT:
1527 info->commit = true;
1528 break;
1529#ifdef CONFIG_NF_CONNTRACK_ZONES
1530 case OVS_CT_ATTR_ZONE:
1531 info->zone.id = nla_get_u16(a);
1532 break;
1533#endif
1534#ifdef CONFIG_NF_CONNTRACK_MARK
1535 case OVS_CT_ATTR_MARK: {
1536 struct md_mark *mark = nla_data(a);
1537
1538 if (!mark->mask) {
1539 OVS_NLERR(log, "ct_mark mask cannot be 0");
1540 return -EINVAL;
1541 }
1542 info->mark = *mark;
1543 break;
1544 }
1545#endif
1546#ifdef CONFIG_NF_CONNTRACK_LABELS
1547 case OVS_CT_ATTR_LABELS: {
1548 struct md_labels *labels = nla_data(a);
1549
1550 if (!labels_nonzero(&labels->mask)) {
1551 OVS_NLERR(log, "ct_labels mask cannot be 0");
1552 return -EINVAL;
1553 }
1554 info->labels = *labels;
1555 break;
1556 }
1557#endif
1558 case OVS_CT_ATTR_HELPER:
1559 *helper = nla_data(a);
1560 if (!memchr(*helper, '\0', nla_len(a))) {
1561 OVS_NLERR(log, "Invalid conntrack helper");
1562 return -EINVAL;
1563 }
1564 break;
1565#if IS_ENABLED(CONFIG_NF_NAT)
1566 case OVS_CT_ATTR_NAT: {
1567 int err = parse_nat(a, info, log);
1568
1569 if (err)
1570 return err;
1571 break;
1572 }
1573#endif
1574 case OVS_CT_ATTR_EVENTMASK:
1575 info->have_eventmask = true;
1576 info->eventmask = nla_get_u32(a);
1577 break;
1578#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
1579 case OVS_CT_ATTR_TIMEOUT:
1580 memcpy(info->timeout, nla_data(a), nla_len(a));
1581 if (!memchr(info->timeout, '\0', nla_len(a))) {
1582 OVS_NLERR(log, "Invalid conntrack timeout");
1583 return -EINVAL;
1584 }
1585 break;
1586#endif
1587
1588 default:
1589 OVS_NLERR(log, "Unknown conntrack attr (%d)",
1590 type);
1591 return -EINVAL;
1592 }
1593 }
1594
1595#ifdef CONFIG_NF_CONNTRACK_MARK
1596 if (!info->commit && info->mark.mask) {
1597 OVS_NLERR(log,
1598 "Setting conntrack mark requires 'commit' flag.");
1599 return -EINVAL;
1600 }
1601#endif
1602#ifdef CONFIG_NF_CONNTRACK_LABELS
1603 if (!info->commit && labels_nonzero(&info->labels.mask)) {
1604 OVS_NLERR(log,
1605 "Setting conntrack labels requires 'commit' flag.");
1606 return -EINVAL;
1607 }
1608#endif
1609 if (rem > 0) {
1610 OVS_NLERR(log, "Conntrack attr has %d unknown bytes", rem);
1611 return -EINVAL;
1612 }
1613
1614 return 0;
1615}
1616
1617bool ovs_ct_verify(struct net *net, enum ovs_key_attr attr)
1618{
1619 if (attr == OVS_KEY_ATTR_CT_STATE)
1620 return true;
1621 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1622 attr == OVS_KEY_ATTR_CT_ZONE)
1623 return true;
1624 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1625 attr == OVS_KEY_ATTR_CT_MARK)
1626 return true;
1627 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1628 attr == OVS_KEY_ATTR_CT_LABELS) {
1629 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
1630
1631 return ovs_net->xt_label;
1632 }
1633
1634 return false;
1635}
1636
1637int ovs_ct_copy_action(struct net *net, const struct nlattr *attr,
1638 const struct sw_flow_key *key,
1639 struct sw_flow_actions **sfa, bool log)
1640{
1641 struct ovs_conntrack_info ct_info;
1642 const char *helper = NULL;
1643 u16 family;
1644 int err;
1645
1646 family = key_to_nfproto(key);
1647 if (family == NFPROTO_UNSPEC) {
1648 OVS_NLERR(log, "ct family unspecified");
1649 return -EINVAL;
1650 }
1651
1652 memset(&ct_info, 0, sizeof(ct_info));
1653 ct_info.family = family;
1654
1655 nf_ct_zone_init(&ct_info.zone, NF_CT_DEFAULT_ZONE_ID,
1656 NF_CT_DEFAULT_ZONE_DIR, 0);
1657
1658 err = parse_ct(attr, &ct_info, &helper, log);
1659 if (err)
1660 return err;
1661
1662 /* Set up template for tracking connections in specific zones. */
1663 ct_info.ct = nf_ct_tmpl_alloc(net, &ct_info.zone, GFP_KERNEL);
1664 if (!ct_info.ct) {
1665 OVS_NLERR(log, "Failed to allocate conntrack template");
1666 return -ENOMEM;
1667 }
1668
1669 if (ct_info.timeout[0]) {
1670 if (nf_ct_set_timeout(net, ct_info.ct, family, key->ip.proto,
1671 ct_info.timeout))
1672 pr_info_ratelimited("Failed to associated timeout "
1673 "policy `%s'\n", ct_info.timeout);
1674 else
1675 ct_info.nf_ct_timeout = rcu_dereference(
1676 nf_ct_timeout_find(ct_info.ct)->timeout);
1677
1678 }
1679
1680 if (helper) {
1681 err = ovs_ct_add_helper(&ct_info, helper, key, log);
1682 if (err)
1683 goto err_free_ct;
1684 }
1685
1686 err = ovs_nla_add_action(sfa, OVS_ACTION_ATTR_CT, &ct_info,
1687 sizeof(ct_info), log);
1688 if (err)
1689 goto err_free_ct;
1690
1691 __set_bit(IPS_CONFIRMED_BIT, &ct_info.ct->status);
1692 nf_conntrack_get(&ct_info.ct->ct_general);
1693 return 0;
1694err_free_ct:
1695 __ovs_ct_free_action(&ct_info);
1696 return err;
1697}
1698
1699#if IS_ENABLED(CONFIG_NF_NAT)
1700static bool ovs_ct_nat_to_attr(const struct ovs_conntrack_info *info,
1701 struct sk_buff *skb)
1702{
1703 struct nlattr *start;
1704
1705 start = nla_nest_start_noflag(skb, OVS_CT_ATTR_NAT);
1706 if (!start)
1707 return false;
1708
1709 if (info->nat & OVS_CT_SRC_NAT) {
1710 if (nla_put_flag(skb, OVS_NAT_ATTR_SRC))
1711 return false;
1712 } else if (info->nat & OVS_CT_DST_NAT) {
1713 if (nla_put_flag(skb, OVS_NAT_ATTR_DST))
1714 return false;
1715 } else {
1716 goto out;
1717 }
1718
1719 if (info->range.flags & NF_NAT_RANGE_MAP_IPS) {
1720 if (IS_ENABLED(CONFIG_NF_NAT) &&
1721 info->family == NFPROTO_IPV4) {
1722 if (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MIN,
1723 info->range.min_addr.ip) ||
1724 (info->range.max_addr.ip
1725 != info->range.min_addr.ip &&
1726 (nla_put_in_addr(skb, OVS_NAT_ATTR_IP_MAX,
1727 info->range.max_addr.ip))))
1728 return false;
1729 } else if (IS_ENABLED(CONFIG_IPV6) &&
1730 info->family == NFPROTO_IPV6) {
1731 if (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MIN,
1732 &info->range.min_addr.in6) ||
1733 (memcmp(&info->range.max_addr.in6,
1734 &info->range.min_addr.in6,
1735 sizeof(info->range.max_addr.in6)) &&
1736 (nla_put_in6_addr(skb, OVS_NAT_ATTR_IP_MAX,
1737 &info->range.max_addr.in6))))
1738 return false;
1739 } else {
1740 return false;
1741 }
1742 }
1743 if (info->range.flags & NF_NAT_RANGE_PROTO_SPECIFIED &&
1744 (nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MIN,
1745 ntohs(info->range.min_proto.all)) ||
1746 (info->range.max_proto.all != info->range.min_proto.all &&
1747 nla_put_u16(skb, OVS_NAT_ATTR_PROTO_MAX,
1748 ntohs(info->range.max_proto.all)))))
1749 return false;
1750
1751 if (info->range.flags & NF_NAT_RANGE_PERSISTENT &&
1752 nla_put_flag(skb, OVS_NAT_ATTR_PERSISTENT))
1753 return false;
1754 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM &&
1755 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_HASH))
1756 return false;
1757 if (info->range.flags & NF_NAT_RANGE_PROTO_RANDOM_FULLY &&
1758 nla_put_flag(skb, OVS_NAT_ATTR_PROTO_RANDOM))
1759 return false;
1760out:
1761 nla_nest_end(skb, start);
1762
1763 return true;
1764}
1765#endif
1766
1767int ovs_ct_action_to_attr(const struct ovs_conntrack_info *ct_info,
1768 struct sk_buff *skb)
1769{
1770 struct nlattr *start;
1771
1772 start = nla_nest_start_noflag(skb, OVS_ACTION_ATTR_CT);
1773 if (!start)
1774 return -EMSGSIZE;
1775
1776 if (ct_info->commit && nla_put_flag(skb, ct_info->force
1777 ? OVS_CT_ATTR_FORCE_COMMIT
1778 : OVS_CT_ATTR_COMMIT))
1779 return -EMSGSIZE;
1780 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1781 nla_put_u16(skb, OVS_CT_ATTR_ZONE, ct_info->zone.id))
1782 return -EMSGSIZE;
1783 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) && ct_info->mark.mask &&
1784 nla_put(skb, OVS_CT_ATTR_MARK, sizeof(ct_info->mark),
1785 &ct_info->mark))
1786 return -EMSGSIZE;
1787 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1788 labels_nonzero(&ct_info->labels.mask) &&
1789 nla_put(skb, OVS_CT_ATTR_LABELS, sizeof(ct_info->labels),
1790 &ct_info->labels))
1791 return -EMSGSIZE;
1792 if (ct_info->helper) {
1793 if (nla_put_string(skb, OVS_CT_ATTR_HELPER,
1794 ct_info->helper->name))
1795 return -EMSGSIZE;
1796 }
1797 if (ct_info->have_eventmask &&
1798 nla_put_u32(skb, OVS_CT_ATTR_EVENTMASK, ct_info->eventmask))
1799 return -EMSGSIZE;
1800 if (ct_info->timeout[0]) {
1801 if (nla_put_string(skb, OVS_CT_ATTR_TIMEOUT, ct_info->timeout))
1802 return -EMSGSIZE;
1803 }
1804
1805#if IS_ENABLED(CONFIG_NF_NAT)
1806 if (ct_info->nat && !ovs_ct_nat_to_attr(ct_info, skb))
1807 return -EMSGSIZE;
1808#endif
1809 nla_nest_end(skb, start);
1810
1811 return 0;
1812}
1813
1814void ovs_ct_free_action(const struct nlattr *a)
1815{
1816 struct ovs_conntrack_info *ct_info = nla_data(a);
1817
1818 __ovs_ct_free_action(ct_info);
1819}
1820
1821static void __ovs_ct_free_action(struct ovs_conntrack_info *ct_info)
1822{
1823 if (ct_info->helper) {
1824#if IS_ENABLED(CONFIG_NF_NAT)
1825 if (ct_info->nat)
1826 nf_nat_helper_put(ct_info->helper);
1827#endif
1828 nf_conntrack_helper_put(ct_info->helper);
1829 }
1830 if (ct_info->ct) {
1831 if (ct_info->timeout[0])
1832 nf_ct_destroy_timeout(ct_info->ct);
1833 nf_ct_tmpl_free(ct_info->ct);
1834 }
1835}
1836
1837#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
1838static int ovs_ct_limit_init(struct net *net, struct ovs_net *ovs_net)
1839{
1840 int i, err;
1841
1842 ovs_net->ct_limit_info = kmalloc(sizeof(*ovs_net->ct_limit_info),
1843 GFP_KERNEL);
1844 if (!ovs_net->ct_limit_info)
1845 return -ENOMEM;
1846
1847 ovs_net->ct_limit_info->default_limit = OVS_CT_LIMIT_DEFAULT;
1848 ovs_net->ct_limit_info->limits =
1849 kmalloc_array(CT_LIMIT_HASH_BUCKETS, sizeof(struct hlist_head),
1850 GFP_KERNEL);
1851 if (!ovs_net->ct_limit_info->limits) {
1852 kfree(ovs_net->ct_limit_info);
1853 return -ENOMEM;
1854 }
1855
1856 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; i++)
1857 INIT_HLIST_HEAD(&ovs_net->ct_limit_info->limits[i]);
1858
1859 ovs_net->ct_limit_info->data =
1860 nf_conncount_init(net, NFPROTO_INET, sizeof(u32));
1861
1862 if (IS_ERR(ovs_net->ct_limit_info->data)) {
1863 err = PTR_ERR(ovs_net->ct_limit_info->data);
1864 kfree(ovs_net->ct_limit_info->limits);
1865 kfree(ovs_net->ct_limit_info);
1866 pr_err("openvswitch: failed to init nf_conncount %d\n", err);
1867 return err;
1868 }
1869 return 0;
1870}
1871
1872static void ovs_ct_limit_exit(struct net *net, struct ovs_net *ovs_net)
1873{
1874 const struct ovs_ct_limit_info *info = ovs_net->ct_limit_info;
1875 int i;
1876
1877 nf_conncount_destroy(net, NFPROTO_INET, info->data);
1878 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
1879 struct hlist_head *head = &info->limits[i];
1880 struct ovs_ct_limit *ct_limit;
1881
1882 hlist_for_each_entry_rcu(ct_limit, head, hlist_node)
1883 kfree_rcu(ct_limit, rcu);
1884 }
1885 kfree(ovs_net->ct_limit_info->limits);
1886 kfree(ovs_net->ct_limit_info);
1887}
1888
1889static struct sk_buff *
1890ovs_ct_limit_cmd_reply_start(struct genl_info *info, u8 cmd,
1891 struct ovs_header **ovs_reply_header)
1892{
1893 struct ovs_header *ovs_header = info->userhdr;
1894 struct sk_buff *skb;
1895
1896 skb = genlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1897 if (!skb)
1898 return ERR_PTR(-ENOMEM);
1899
1900 *ovs_reply_header = genlmsg_put(skb, info->snd_portid,
1901 info->snd_seq,
1902 &dp_ct_limit_genl_family, 0, cmd);
1903
1904 if (!*ovs_reply_header) {
1905 nlmsg_free(skb);
1906 return ERR_PTR(-EMSGSIZE);
1907 }
1908 (*ovs_reply_header)->dp_ifindex = ovs_header->dp_ifindex;
1909
1910 return skb;
1911}
1912
1913static bool check_zone_id(int zone_id, u16 *pzone)
1914{
1915 if (zone_id >= 0 && zone_id <= 65535) {
1916 *pzone = (u16)zone_id;
1917 return true;
1918 }
1919 return false;
1920}
1921
1922static int ovs_ct_limit_set_zone_limit(struct nlattr *nla_zone_limit,
1923 struct ovs_ct_limit_info *info)
1924{
1925 struct ovs_zone_limit *zone_limit;
1926 int rem;
1927 u16 zone;
1928
1929 rem = NLA_ALIGN(nla_len(nla_zone_limit));
1930 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
1931
1932 while (rem >= sizeof(*zone_limit)) {
1933 if (unlikely(zone_limit->zone_id ==
1934 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
1935 ovs_lock();
1936 info->default_limit = zone_limit->limit;
1937 ovs_unlock();
1938 } else if (unlikely(!check_zone_id(
1939 zone_limit->zone_id, &zone))) {
1940 OVS_NLERR(true, "zone id is out of range");
1941 } else {
1942 struct ovs_ct_limit *ct_limit;
1943
1944 ct_limit = kmalloc(sizeof(*ct_limit), GFP_KERNEL);
1945 if (!ct_limit)
1946 return -ENOMEM;
1947
1948 ct_limit->zone = zone;
1949 ct_limit->limit = zone_limit->limit;
1950
1951 ovs_lock();
1952 ct_limit_set(info, ct_limit);
1953 ovs_unlock();
1954 }
1955 rem -= NLA_ALIGN(sizeof(*zone_limit));
1956 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
1957 NLA_ALIGN(sizeof(*zone_limit)));
1958 }
1959
1960 if (rem)
1961 OVS_NLERR(true, "set zone limit has %d unknown bytes", rem);
1962
1963 return 0;
1964}
1965
1966static int ovs_ct_limit_del_zone_limit(struct nlattr *nla_zone_limit,
1967 struct ovs_ct_limit_info *info)
1968{
1969 struct ovs_zone_limit *zone_limit;
1970 int rem;
1971 u16 zone;
1972
1973 rem = NLA_ALIGN(nla_len(nla_zone_limit));
1974 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
1975
1976 while (rem >= sizeof(*zone_limit)) {
1977 if (unlikely(zone_limit->zone_id ==
1978 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
1979 ovs_lock();
1980 info->default_limit = OVS_CT_LIMIT_DEFAULT;
1981 ovs_unlock();
1982 } else if (unlikely(!check_zone_id(
1983 zone_limit->zone_id, &zone))) {
1984 OVS_NLERR(true, "zone id is out of range");
1985 } else {
1986 ovs_lock();
1987 ct_limit_del(info, zone);
1988 ovs_unlock();
1989 }
1990 rem -= NLA_ALIGN(sizeof(*zone_limit));
1991 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
1992 NLA_ALIGN(sizeof(*zone_limit)));
1993 }
1994
1995 if (rem)
1996 OVS_NLERR(true, "del zone limit has %d unknown bytes", rem);
1997
1998 return 0;
1999}
2000
2001static int ovs_ct_limit_get_default_limit(struct ovs_ct_limit_info *info,
2002 struct sk_buff *reply)
2003{
2004 struct ovs_zone_limit zone_limit;
2005 int err;
2006
2007 zone_limit.zone_id = OVS_ZONE_LIMIT_DEFAULT_ZONE;
2008 zone_limit.limit = info->default_limit;
2009 err = nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2010 if (err)
2011 return err;
2012
2013 return 0;
2014}
2015
2016static int __ovs_ct_limit_get_zone_limit(struct net *net,
2017 struct nf_conncount_data *data,
2018 u16 zone_id, u32 limit,
2019 struct sk_buff *reply)
2020{
2021 struct nf_conntrack_zone ct_zone;
2022 struct ovs_zone_limit zone_limit;
2023 u32 conncount_key = zone_id;
2024
2025 zone_limit.zone_id = zone_id;
2026 zone_limit.limit = limit;
2027 nf_ct_zone_init(&ct_zone, zone_id, NF_CT_DEFAULT_ZONE_DIR, 0);
2028
2029 zone_limit.count = nf_conncount_count(net, data, &conncount_key, NULL,
2030 &ct_zone);
2031 return nla_put_nohdr(reply, sizeof(zone_limit), &zone_limit);
2032}
2033
2034static int ovs_ct_limit_get_zone_limit(struct net *net,
2035 struct nlattr *nla_zone_limit,
2036 struct ovs_ct_limit_info *info,
2037 struct sk_buff *reply)
2038{
2039 struct ovs_zone_limit *zone_limit;
2040 int rem, err;
2041 u32 limit;
2042 u16 zone;
2043
2044 rem = NLA_ALIGN(nla_len(nla_zone_limit));
2045 zone_limit = (struct ovs_zone_limit *)nla_data(nla_zone_limit);
2046
2047 while (rem >= sizeof(*zone_limit)) {
2048 if (unlikely(zone_limit->zone_id ==
2049 OVS_ZONE_LIMIT_DEFAULT_ZONE)) {
2050 err = ovs_ct_limit_get_default_limit(info, reply);
2051 if (err)
2052 return err;
2053 } else if (unlikely(!check_zone_id(zone_limit->zone_id,
2054 &zone))) {
2055 OVS_NLERR(true, "zone id is out of range");
2056 } else {
2057 rcu_read_lock();
2058 limit = ct_limit_get(info, zone);
2059 rcu_read_unlock();
2060
2061 err = __ovs_ct_limit_get_zone_limit(
2062 net, info->data, zone, limit, reply);
2063 if (err)
2064 return err;
2065 }
2066 rem -= NLA_ALIGN(sizeof(*zone_limit));
2067 zone_limit = (struct ovs_zone_limit *)((u8 *)zone_limit +
2068 NLA_ALIGN(sizeof(*zone_limit)));
2069 }
2070
2071 if (rem)
2072 OVS_NLERR(true, "get zone limit has %d unknown bytes", rem);
2073
2074 return 0;
2075}
2076
2077static int ovs_ct_limit_get_all_zone_limit(struct net *net,
2078 struct ovs_ct_limit_info *info,
2079 struct sk_buff *reply)
2080{
2081 struct ovs_ct_limit *ct_limit;
2082 struct hlist_head *head;
2083 int i, err = 0;
2084
2085 err = ovs_ct_limit_get_default_limit(info, reply);
2086 if (err)
2087 return err;
2088
2089 rcu_read_lock();
2090 for (i = 0; i < CT_LIMIT_HASH_BUCKETS; ++i) {
2091 head = &info->limits[i];
2092 hlist_for_each_entry_rcu(ct_limit, head, hlist_node) {
2093 err = __ovs_ct_limit_get_zone_limit(net, info->data,
2094 ct_limit->zone, ct_limit->limit, reply);
2095 if (err)
2096 goto exit_err;
2097 }
2098 }
2099
2100exit_err:
2101 rcu_read_unlock();
2102 return err;
2103}
2104
2105static int ovs_ct_limit_cmd_set(struct sk_buff *skb, struct genl_info *info)
2106{
2107 struct nlattr **a = info->attrs;
2108 struct sk_buff *reply;
2109 struct ovs_header *ovs_reply_header;
2110 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2111 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2112 int err;
2113
2114 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_SET,
2115 &ovs_reply_header);
2116 if (IS_ERR(reply))
2117 return PTR_ERR(reply);
2118
2119 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2120 err = -EINVAL;
2121 goto exit_err;
2122 }
2123
2124 err = ovs_ct_limit_set_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2125 ct_limit_info);
2126 if (err)
2127 goto exit_err;
2128
2129 static_branch_enable(&ovs_ct_limit_enabled);
2130
2131 genlmsg_end(reply, ovs_reply_header);
2132 return genlmsg_reply(reply, info);
2133
2134exit_err:
2135 nlmsg_free(reply);
2136 return err;
2137}
2138
2139static int ovs_ct_limit_cmd_del(struct sk_buff *skb, struct genl_info *info)
2140{
2141 struct nlattr **a = info->attrs;
2142 struct sk_buff *reply;
2143 struct ovs_header *ovs_reply_header;
2144 struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
2145 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2146 int err;
2147
2148 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_DEL,
2149 &ovs_reply_header);
2150 if (IS_ERR(reply))
2151 return PTR_ERR(reply);
2152
2153 if (!a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2154 err = -EINVAL;
2155 goto exit_err;
2156 }
2157
2158 err = ovs_ct_limit_del_zone_limit(a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT],
2159 ct_limit_info);
2160 if (err)
2161 goto exit_err;
2162
2163 genlmsg_end(reply, ovs_reply_header);
2164 return genlmsg_reply(reply, info);
2165
2166exit_err:
2167 nlmsg_free(reply);
2168 return err;
2169}
2170
2171static int ovs_ct_limit_cmd_get(struct sk_buff *skb, struct genl_info *info)
2172{
2173 struct nlattr **a = info->attrs;
2174 struct nlattr *nla_reply;
2175 struct sk_buff *reply;
2176 struct ovs_header *ovs_reply_header;
2177 struct net *net = sock_net(skb->sk);
2178 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2179 struct ovs_ct_limit_info *ct_limit_info = ovs_net->ct_limit_info;
2180 int err;
2181
2182 reply = ovs_ct_limit_cmd_reply_start(info, OVS_CT_LIMIT_CMD_GET,
2183 &ovs_reply_header);
2184 if (IS_ERR(reply))
2185 return PTR_ERR(reply);
2186
2187 nla_reply = nla_nest_start_noflag(reply, OVS_CT_LIMIT_ATTR_ZONE_LIMIT);
2188 if (!nla_reply) {
2189 err = -EMSGSIZE;
2190 goto exit_err;
2191 }
2192
2193 if (a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT]) {
2194 err = ovs_ct_limit_get_zone_limit(
2195 net, a[OVS_CT_LIMIT_ATTR_ZONE_LIMIT], ct_limit_info,
2196 reply);
2197 if (err)
2198 goto exit_err;
2199 } else {
2200 err = ovs_ct_limit_get_all_zone_limit(net, ct_limit_info,
2201 reply);
2202 if (err)
2203 goto exit_err;
2204 }
2205
2206 nla_nest_end(reply, nla_reply);
2207 genlmsg_end(reply, ovs_reply_header);
2208 return genlmsg_reply(reply, info);
2209
2210exit_err:
2211 nlmsg_free(reply);
2212 return err;
2213}
2214
2215static struct genl_ops ct_limit_genl_ops[] = {
2216 { .cmd = OVS_CT_LIMIT_CMD_SET,
2217 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2218 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2219 * privilege. */
2220 .doit = ovs_ct_limit_cmd_set,
2221 },
2222 { .cmd = OVS_CT_LIMIT_CMD_DEL,
2223 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2224 .flags = GENL_ADMIN_PERM, /* Requires CAP_NET_ADMIN
2225 * privilege. */
2226 .doit = ovs_ct_limit_cmd_del,
2227 },
2228 { .cmd = OVS_CT_LIMIT_CMD_GET,
2229 .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
2230 .flags = 0, /* OK for unprivileged users. */
2231 .doit = ovs_ct_limit_cmd_get,
2232 },
2233};
2234
2235static const struct genl_multicast_group ovs_ct_limit_multicast_group = {
2236 .name = OVS_CT_LIMIT_MCGROUP,
2237};
2238
2239struct genl_family dp_ct_limit_genl_family __ro_after_init = {
2240 .hdrsize = sizeof(struct ovs_header),
2241 .name = OVS_CT_LIMIT_FAMILY,
2242 .version = OVS_CT_LIMIT_VERSION,
2243 .maxattr = OVS_CT_LIMIT_ATTR_MAX,
2244 .policy = ct_limit_policy,
2245 .netnsok = true,
2246 .parallel_ops = true,
2247 .ops = ct_limit_genl_ops,
2248 .n_ops = ARRAY_SIZE(ct_limit_genl_ops),
2249 .mcgrps = &ovs_ct_limit_multicast_group,
2250 .n_mcgrps = 1,
2251 .module = THIS_MODULE,
2252};
2253#endif
2254
2255int ovs_ct_init(struct net *net)
2256{
2257 unsigned int n_bits = sizeof(struct ovs_key_ct_labels) * BITS_PER_BYTE;
2258 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2259
2260 if (nf_connlabels_get(net, n_bits - 1)) {
2261 ovs_net->xt_label = false;
2262 OVS_NLERR(true, "Failed to set connlabel length");
2263 } else {
2264 ovs_net->xt_label = true;
2265 }
2266
2267#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2268 return ovs_ct_limit_init(net, ovs_net);
2269#else
2270 return 0;
2271#endif
2272}
2273
2274void ovs_ct_exit(struct net *net)
2275{
2276 struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
2277
2278#if IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
2279 ovs_ct_limit_exit(net, ovs_net);
2280#endif
2281
2282 if (ovs_net->xt_label)
2283 nf_connlabels_put(net);
2284}