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1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2/* -
3 * net/sched/act_ct.c Connection Tracking action
4 *
5 * Authors: Paul Blakey <paulb@mellanox.com>
6 * Yossi Kuperman <yossiku@mellanox.com>
7 * Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
8 */
9
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/kernel.h>
13#include <linux/skbuff.h>
14#include <linux/rtnetlink.h>
15#include <linux/pkt_cls.h>
16#include <linux/ip.h>
17#include <linux/ipv6.h>
18#include <linux/rhashtable.h>
19#include <net/netlink.h>
20#include <net/pkt_sched.h>
21#include <net/pkt_cls.h>
22#include <net/act_api.h>
23#include <net/ip.h>
24#include <net/ipv6_frag.h>
25#include <uapi/linux/tc_act/tc_ct.h>
26#include <net/tc_act/tc_ct.h>
27
28#include <net/netfilter/nf_flow_table.h>
29#include <net/netfilter/nf_conntrack.h>
30#include <net/netfilter/nf_conntrack_core.h>
31#include <net/netfilter/nf_conntrack_zones.h>
32#include <net/netfilter/nf_conntrack_helper.h>
33#include <net/netfilter/nf_conntrack_acct.h>
34#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
35#include <uapi/linux/netfilter/nf_nat.h>
36
37static struct workqueue_struct *act_ct_wq;
38static struct rhashtable zones_ht;
39static DEFINE_MUTEX(zones_mutex);
40
41struct tcf_ct_flow_table {
42 struct rhash_head node; /* In zones tables */
43
44 struct rcu_work rwork;
45 struct nf_flowtable nf_ft;
46 refcount_t ref;
47 u16 zone;
48
49 bool dying;
50};
51
52static const struct rhashtable_params zones_params = {
53 .head_offset = offsetof(struct tcf_ct_flow_table, node),
54 .key_offset = offsetof(struct tcf_ct_flow_table, zone),
55 .key_len = sizeof_field(struct tcf_ct_flow_table, zone),
56 .automatic_shrinking = true,
57};
58
59static struct flow_action_entry *
60tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action)
61{
62 int i = flow_action->num_entries++;
63
64 return &flow_action->entries[i];
65}
66
67static void tcf_ct_add_mangle_action(struct flow_action *action,
68 enum flow_action_mangle_base htype,
69 u32 offset,
70 u32 mask,
71 u32 val)
72{
73 struct flow_action_entry *entry;
74
75 entry = tcf_ct_flow_table_flow_action_get_next(action);
76 entry->id = FLOW_ACTION_MANGLE;
77 entry->mangle.htype = htype;
78 entry->mangle.mask = ~mask;
79 entry->mangle.offset = offset;
80 entry->mangle.val = val;
81}
82
83/* The following nat helper functions check if the inverted reverse tuple
84 * (target) is different then the current dir tuple - meaning nat for ports
85 * and/or ip is needed, and add the relevant mangle actions.
86 */
87static void
88tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple,
89 struct nf_conntrack_tuple target,
90 struct flow_action *action)
91{
92 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
93 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
94 offsetof(struct iphdr, saddr),
95 0xFFFFFFFF,
96 be32_to_cpu(target.src.u3.ip));
97 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
98 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
99 offsetof(struct iphdr, daddr),
100 0xFFFFFFFF,
101 be32_to_cpu(target.dst.u3.ip));
102}
103
104static void
105tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action,
106 union nf_inet_addr *addr,
107 u32 offset)
108{
109 int i;
110
111 for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++)
112 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
113 i * sizeof(u32) + offset,
114 0xFFFFFFFF, be32_to_cpu(addr->ip6[i]));
115}
116
117static void
118tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple,
119 struct nf_conntrack_tuple target,
120 struct flow_action *action)
121{
122 if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
123 tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3,
124 offsetof(struct ipv6hdr,
125 saddr));
126 if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
127 tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3,
128 offsetof(struct ipv6hdr,
129 daddr));
130}
131
132static void
133tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple,
134 struct nf_conntrack_tuple target,
135 struct flow_action *action)
136{
137 __be16 target_src = target.src.u.tcp.port;
138 __be16 target_dst = target.dst.u.tcp.port;
139
140 if (target_src != tuple->src.u.tcp.port)
141 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
142 offsetof(struct tcphdr, source),
143 0xFFFF, be16_to_cpu(target_src));
144 if (target_dst != tuple->dst.u.tcp.port)
145 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
146 offsetof(struct tcphdr, dest),
147 0xFFFF, be16_to_cpu(target_dst));
148}
149
150static void
151tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple,
152 struct nf_conntrack_tuple target,
153 struct flow_action *action)
154{
155 __be16 target_src = target.src.u.udp.port;
156 __be16 target_dst = target.dst.u.udp.port;
157
158 if (target_src != tuple->src.u.udp.port)
159 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
160 offsetof(struct udphdr, source),
161 0xFFFF, be16_to_cpu(target_src));
162 if (target_dst != tuple->dst.u.udp.port)
163 tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
164 offsetof(struct udphdr, dest),
165 0xFFFF, be16_to_cpu(target_dst));
166}
167
168static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct,
169 enum ip_conntrack_dir dir,
170 struct flow_action *action)
171{
172 struct nf_conn_labels *ct_labels;
173 struct flow_action_entry *entry;
174 enum ip_conntrack_info ctinfo;
175 u32 *act_ct_labels;
176
177 entry = tcf_ct_flow_table_flow_action_get_next(action);
178 entry->id = FLOW_ACTION_CT_METADATA;
179#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
180 entry->ct_metadata.mark = ct->mark;
181#endif
182 ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
183 IP_CT_ESTABLISHED_REPLY;
184 /* aligns with the CT reference on the SKB nf_ct_set */
185 entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
186
187 act_ct_labels = entry->ct_metadata.labels;
188 ct_labels = nf_ct_labels_find(ct);
189 if (ct_labels)
190 memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
191 else
192 memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
193}
194
195static int tcf_ct_flow_table_add_action_nat(struct net *net,
196 struct nf_conn *ct,
197 enum ip_conntrack_dir dir,
198 struct flow_action *action)
199{
200 const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
201 struct nf_conntrack_tuple target;
202
203 if (!(ct->status & IPS_NAT_MASK))
204 return 0;
205
206 nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
207
208 switch (tuple->src.l3num) {
209 case NFPROTO_IPV4:
210 tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
211 action);
212 break;
213 case NFPROTO_IPV6:
214 tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
215 action);
216 break;
217 default:
218 return -EOPNOTSUPP;
219 }
220
221 switch (nf_ct_protonum(ct)) {
222 case IPPROTO_TCP:
223 tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
224 break;
225 case IPPROTO_UDP:
226 tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
227 break;
228 default:
229 return -EOPNOTSUPP;
230 }
231
232 return 0;
233}
234
235static int tcf_ct_flow_table_fill_actions(struct net *net,
236 const struct flow_offload *flow,
237 enum flow_offload_tuple_dir tdir,
238 struct nf_flow_rule *flow_rule)
239{
240 struct flow_action *action = &flow_rule->rule->action;
241 int num_entries = action->num_entries;
242 struct nf_conn *ct = flow->ct;
243 enum ip_conntrack_dir dir;
244 int i, err;
245
246 switch (tdir) {
247 case FLOW_OFFLOAD_DIR_ORIGINAL:
248 dir = IP_CT_DIR_ORIGINAL;
249 break;
250 case FLOW_OFFLOAD_DIR_REPLY:
251 dir = IP_CT_DIR_REPLY;
252 break;
253 default:
254 return -EOPNOTSUPP;
255 }
256
257 err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
258 if (err)
259 goto err_nat;
260
261 tcf_ct_flow_table_add_action_meta(ct, dir, action);
262 return 0;
263
264err_nat:
265 /* Clear filled actions */
266 for (i = num_entries; i < action->num_entries; i++)
267 memset(&action->entries[i], 0, sizeof(action->entries[i]));
268 action->num_entries = num_entries;
269
270 return err;
271}
272
273static struct nf_flowtable_type flowtable_ct = {
274 .action = tcf_ct_flow_table_fill_actions,
275 .owner = THIS_MODULE,
276};
277
278static int tcf_ct_flow_table_get(struct tcf_ct_params *params)
279{
280 struct tcf_ct_flow_table *ct_ft;
281 int err = -ENOMEM;
282
283 mutex_lock(&zones_mutex);
284 ct_ft = rhashtable_lookup_fast(&zones_ht, ¶ms->zone, zones_params);
285 if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
286 goto out_unlock;
287
288 ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
289 if (!ct_ft)
290 goto err_alloc;
291 refcount_set(&ct_ft->ref, 1);
292
293 ct_ft->zone = params->zone;
294 err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
295 if (err)
296 goto err_insert;
297
298 ct_ft->nf_ft.type = &flowtable_ct;
299 ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD;
300 err = nf_flow_table_init(&ct_ft->nf_ft);
301 if (err)
302 goto err_init;
303
304 __module_get(THIS_MODULE);
305out_unlock:
306 params->ct_ft = ct_ft;
307 params->nf_ft = &ct_ft->nf_ft;
308 mutex_unlock(&zones_mutex);
309
310 return 0;
311
312err_init:
313 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
314err_insert:
315 kfree(ct_ft);
316err_alloc:
317 mutex_unlock(&zones_mutex);
318 return err;
319}
320
321static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
322{
323 struct tcf_ct_flow_table *ct_ft;
324
325 ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
326 rwork);
327 nf_flow_table_free(&ct_ft->nf_ft);
328 kfree(ct_ft);
329
330 module_put(THIS_MODULE);
331}
332
333static void tcf_ct_flow_table_put(struct tcf_ct_params *params)
334{
335 struct tcf_ct_flow_table *ct_ft = params->ct_ft;
336
337 if (refcount_dec_and_test(¶ms->ct_ft->ref)) {
338 rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
339 INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
340 queue_rcu_work(act_ct_wq, &ct_ft->rwork);
341 }
342}
343
344static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
345 struct nf_conn *ct,
346 bool tcp)
347{
348 struct flow_offload *entry;
349 int err;
350
351 if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
352 return;
353
354 entry = flow_offload_alloc(ct);
355 if (!entry) {
356 WARN_ON_ONCE(1);
357 goto err_alloc;
358 }
359
360 if (tcp) {
361 ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
362 ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
363 }
364
365 err = flow_offload_add(&ct_ft->nf_ft, entry);
366 if (err)
367 goto err_add;
368
369 return;
370
371err_add:
372 flow_offload_free(entry);
373err_alloc:
374 clear_bit(IPS_OFFLOAD_BIT, &ct->status);
375}
376
377static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
378 struct nf_conn *ct,
379 enum ip_conntrack_info ctinfo)
380{
381 bool tcp = false;
382
383 if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
384 return;
385
386 switch (nf_ct_protonum(ct)) {
387 case IPPROTO_TCP:
388 tcp = true;
389 if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
390 return;
391 break;
392 case IPPROTO_UDP:
393 break;
394 default:
395 return;
396 }
397
398 if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
399 ct->status & IPS_SEQ_ADJUST)
400 return;
401
402 tcf_ct_flow_table_add(ct_ft, ct, tcp);
403}
404
405static bool
406tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
407 struct flow_offload_tuple *tuple,
408 struct tcphdr **tcph)
409{
410 struct flow_ports *ports;
411 unsigned int thoff;
412 struct iphdr *iph;
413
414 if (!pskb_network_may_pull(skb, sizeof(*iph)))
415 return false;
416
417 iph = ip_hdr(skb);
418 thoff = iph->ihl * 4;
419
420 if (ip_is_fragment(iph) ||
421 unlikely(thoff != sizeof(struct iphdr)))
422 return false;
423
424 if (iph->protocol != IPPROTO_TCP &&
425 iph->protocol != IPPROTO_UDP)
426 return false;
427
428 if (iph->ttl <= 1)
429 return false;
430
431 if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ?
432 thoff + sizeof(struct tcphdr) :
433 thoff + sizeof(*ports)))
434 return false;
435
436 iph = ip_hdr(skb);
437 if (iph->protocol == IPPROTO_TCP)
438 *tcph = (void *)(skb_network_header(skb) + thoff);
439
440 ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
441 tuple->src_v4.s_addr = iph->saddr;
442 tuple->dst_v4.s_addr = iph->daddr;
443 tuple->src_port = ports->source;
444 tuple->dst_port = ports->dest;
445 tuple->l3proto = AF_INET;
446 tuple->l4proto = iph->protocol;
447
448 return true;
449}
450
451static bool
452tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
453 struct flow_offload_tuple *tuple,
454 struct tcphdr **tcph)
455{
456 struct flow_ports *ports;
457 struct ipv6hdr *ip6h;
458 unsigned int thoff;
459
460 if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
461 return false;
462
463 ip6h = ipv6_hdr(skb);
464
465 if (ip6h->nexthdr != IPPROTO_TCP &&
466 ip6h->nexthdr != IPPROTO_UDP)
467 return false;
468
469 if (ip6h->hop_limit <= 1)
470 return false;
471
472 thoff = sizeof(*ip6h);
473 if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ?
474 thoff + sizeof(struct tcphdr) :
475 thoff + sizeof(*ports)))
476 return false;
477
478 ip6h = ipv6_hdr(skb);
479 if (ip6h->nexthdr == IPPROTO_TCP)
480 *tcph = (void *)(skb_network_header(skb) + thoff);
481
482 ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
483 tuple->src_v6 = ip6h->saddr;
484 tuple->dst_v6 = ip6h->daddr;
485 tuple->src_port = ports->source;
486 tuple->dst_port = ports->dest;
487 tuple->l3proto = AF_INET6;
488 tuple->l4proto = ip6h->nexthdr;
489
490 return true;
491}
492
493static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
494 struct sk_buff *skb,
495 u8 family)
496{
497 struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
498 struct flow_offload_tuple_rhash *tuplehash;
499 struct flow_offload_tuple tuple = {};
500 enum ip_conntrack_info ctinfo;
501 struct tcphdr *tcph = NULL;
502 struct flow_offload *flow;
503 struct nf_conn *ct;
504 u8 dir;
505
506 /* Previously seen or loopback */
507 ct = nf_ct_get(skb, &ctinfo);
508 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
509 return false;
510
511 switch (family) {
512 case NFPROTO_IPV4:
513 if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
514 return false;
515 break;
516 case NFPROTO_IPV6:
517 if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
518 return false;
519 break;
520 default:
521 return false;
522 }
523
524 tuplehash = flow_offload_lookup(nf_ft, &tuple);
525 if (!tuplehash)
526 return false;
527
528 dir = tuplehash->tuple.dir;
529 flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
530 ct = flow->ct;
531
532 if (tcph && (unlikely(tcph->fin || tcph->rst))) {
533 flow_offload_teardown(flow);
534 return false;
535 }
536
537 ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
538 IP_CT_ESTABLISHED_REPLY;
539
540 flow_offload_refresh(nf_ft, flow);
541 nf_conntrack_get(&ct->ct_general);
542 nf_ct_set(skb, ct, ctinfo);
543 nf_ct_acct_update(ct, dir, skb->len);
544
545 return true;
546}
547
548static int tcf_ct_flow_tables_init(void)
549{
550 return rhashtable_init(&zones_ht, &zones_params);
551}
552
553static void tcf_ct_flow_tables_uninit(void)
554{
555 rhashtable_destroy(&zones_ht);
556}
557
558static struct tc_action_ops act_ct_ops;
559static unsigned int ct_net_id;
560
561struct tc_ct_action_net {
562 struct tc_action_net tn; /* Must be first */
563 bool labels;
564};
565
566/* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
567static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
568 u16 zone_id, bool force)
569{
570 enum ip_conntrack_info ctinfo;
571 struct nf_conn *ct;
572
573 ct = nf_ct_get(skb, &ctinfo);
574 if (!ct)
575 return false;
576 if (!net_eq(net, read_pnet(&ct->ct_net)))
577 return false;
578 if (nf_ct_zone(ct)->id != zone_id)
579 return false;
580
581 /* Force conntrack entry direction. */
582 if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
583 if (nf_ct_is_confirmed(ct))
584 nf_ct_kill(ct);
585
586 nf_conntrack_put(&ct->ct_general);
587 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
588
589 return false;
590 }
591
592 return true;
593}
594
595/* Trim the skb to the length specified by the IP/IPv6 header,
596 * removing any trailing lower-layer padding. This prepares the skb
597 * for higher-layer processing that assumes skb->len excludes padding
598 * (such as nf_ip_checksum). The caller needs to pull the skb to the
599 * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
600 */
601static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
602{
603 unsigned int len;
604 int err;
605
606 switch (family) {
607 case NFPROTO_IPV4:
608 len = ntohs(ip_hdr(skb)->tot_len);
609 break;
610 case NFPROTO_IPV6:
611 len = sizeof(struct ipv6hdr)
612 + ntohs(ipv6_hdr(skb)->payload_len);
613 break;
614 default:
615 len = skb->len;
616 }
617
618 err = pskb_trim_rcsum(skb, len);
619
620 return err;
621}
622
623static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
624{
625 u8 family = NFPROTO_UNSPEC;
626
627 switch (skb_protocol(skb, true)) {
628 case htons(ETH_P_IP):
629 family = NFPROTO_IPV4;
630 break;
631 case htons(ETH_P_IPV6):
632 family = NFPROTO_IPV6;
633 break;
634 default:
635 break;
636 }
637
638 return family;
639}
640
641static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
642{
643 unsigned int len;
644
645 len = skb_network_offset(skb) + sizeof(struct iphdr);
646 if (unlikely(skb->len < len))
647 return -EINVAL;
648 if (unlikely(!pskb_may_pull(skb, len)))
649 return -ENOMEM;
650
651 *frag = ip_is_fragment(ip_hdr(skb));
652 return 0;
653}
654
655static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
656{
657 unsigned int flags = 0, len, payload_ofs = 0;
658 unsigned short frag_off;
659 int nexthdr;
660
661 len = skb_network_offset(skb) + sizeof(struct ipv6hdr);
662 if (unlikely(skb->len < len))
663 return -EINVAL;
664 if (unlikely(!pskb_may_pull(skb, len)))
665 return -ENOMEM;
666
667 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
668 if (unlikely(nexthdr < 0))
669 return -EPROTO;
670
671 *frag = flags & IP6_FH_F_FRAG;
672 return 0;
673}
674
675static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
676 u8 family, u16 zone, bool *defrag)
677{
678 enum ip_conntrack_info ctinfo;
679 struct qdisc_skb_cb cb;
680 struct nf_conn *ct;
681 int err = 0;
682 bool frag;
683
684 /* Previously seen (loopback)? Ignore. */
685 ct = nf_ct_get(skb, &ctinfo);
686 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
687 return 0;
688
689 if (family == NFPROTO_IPV4)
690 err = tcf_ct_ipv4_is_fragment(skb, &frag);
691 else
692 err = tcf_ct_ipv6_is_fragment(skb, &frag);
693 if (err || !frag)
694 return err;
695
696 skb_get(skb);
697 cb = *qdisc_skb_cb(skb);
698
699 if (family == NFPROTO_IPV4) {
700 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
701
702 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
703 local_bh_disable();
704 err = ip_defrag(net, skb, user);
705 local_bh_enable();
706 if (err && err != -EINPROGRESS)
707 return err;
708
709 if (!err) {
710 *defrag = true;
711 cb.mru = IPCB(skb)->frag_max_size;
712 }
713 } else { /* NFPROTO_IPV6 */
714#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
715 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
716
717 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
718 err = nf_ct_frag6_gather(net, skb, user);
719 if (err && err != -EINPROGRESS)
720 goto out_free;
721
722 if (!err) {
723 *defrag = true;
724 cb.mru = IP6CB(skb)->frag_max_size;
725 }
726#else
727 err = -EOPNOTSUPP;
728 goto out_free;
729#endif
730 }
731
732 *qdisc_skb_cb(skb) = cb;
733 skb_clear_hash(skb);
734 skb->ignore_df = 1;
735 return err;
736
737out_free:
738 kfree_skb(skb);
739 return err;
740}
741
742static void tcf_ct_params_free(struct rcu_head *head)
743{
744 struct tcf_ct_params *params = container_of(head,
745 struct tcf_ct_params, rcu);
746
747 tcf_ct_flow_table_put(params);
748
749 if (params->tmpl)
750 nf_conntrack_put(¶ms->tmpl->ct_general);
751 kfree(params);
752}
753
754#if IS_ENABLED(CONFIG_NF_NAT)
755/* Modelled after nf_nat_ipv[46]_fn().
756 * range is only used for new, uninitialized NAT state.
757 * Returns either NF_ACCEPT or NF_DROP.
758 */
759static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
760 enum ip_conntrack_info ctinfo,
761 const struct nf_nat_range2 *range,
762 enum nf_nat_manip_type maniptype)
763{
764 __be16 proto = skb_protocol(skb, true);
765 int hooknum, err = NF_ACCEPT;
766
767 /* See HOOK2MANIP(). */
768 if (maniptype == NF_NAT_MANIP_SRC)
769 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
770 else
771 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
772
773 switch (ctinfo) {
774 case IP_CT_RELATED:
775 case IP_CT_RELATED_REPLY:
776 if (proto == htons(ETH_P_IP) &&
777 ip_hdr(skb)->protocol == IPPROTO_ICMP) {
778 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
779 hooknum))
780 err = NF_DROP;
781 goto out;
782 } else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) {
783 __be16 frag_off;
784 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
785 int hdrlen = ipv6_skip_exthdr(skb,
786 sizeof(struct ipv6hdr),
787 &nexthdr, &frag_off);
788
789 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
790 if (!nf_nat_icmpv6_reply_translation(skb, ct,
791 ctinfo,
792 hooknum,
793 hdrlen))
794 err = NF_DROP;
795 goto out;
796 }
797 }
798 /* Non-ICMP, fall thru to initialize if needed. */
799 fallthrough;
800 case IP_CT_NEW:
801 /* Seen it before? This can happen for loopback, retrans,
802 * or local packets.
803 */
804 if (!nf_nat_initialized(ct, maniptype)) {
805 /* Initialize according to the NAT action. */
806 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
807 /* Action is set up to establish a new
808 * mapping.
809 */
810 ? nf_nat_setup_info(ct, range, maniptype)
811 : nf_nat_alloc_null_binding(ct, hooknum);
812 if (err != NF_ACCEPT)
813 goto out;
814 }
815 break;
816
817 case IP_CT_ESTABLISHED:
818 case IP_CT_ESTABLISHED_REPLY:
819 break;
820
821 default:
822 err = NF_DROP;
823 goto out;
824 }
825
826 err = nf_nat_packet(ct, ctinfo, hooknum, skb);
827out:
828 return err;
829}
830#endif /* CONFIG_NF_NAT */
831
832static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
833{
834#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
835 u32 new_mark;
836
837 if (!mask)
838 return;
839
840 new_mark = mark | (ct->mark & ~(mask));
841 if (ct->mark != new_mark) {
842 ct->mark = new_mark;
843 if (nf_ct_is_confirmed(ct))
844 nf_conntrack_event_cache(IPCT_MARK, ct);
845 }
846#endif
847}
848
849static void tcf_ct_act_set_labels(struct nf_conn *ct,
850 u32 *labels,
851 u32 *labels_m)
852{
853#if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
854 size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
855
856 if (!memchr_inv(labels_m, 0, labels_sz))
857 return;
858
859 nf_connlabels_replace(ct, labels, labels_m, 4);
860#endif
861}
862
863static int tcf_ct_act_nat(struct sk_buff *skb,
864 struct nf_conn *ct,
865 enum ip_conntrack_info ctinfo,
866 int ct_action,
867 struct nf_nat_range2 *range,
868 bool commit)
869{
870#if IS_ENABLED(CONFIG_NF_NAT)
871 int err;
872 enum nf_nat_manip_type maniptype;
873
874 if (!(ct_action & TCA_CT_ACT_NAT))
875 return NF_ACCEPT;
876
877 /* Add NAT extension if not confirmed yet. */
878 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
879 return NF_DROP; /* Can't NAT. */
880
881 if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) &&
882 (ctinfo != IP_CT_RELATED || commit)) {
883 /* NAT an established or related connection like before. */
884 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
885 /* This is the REPLY direction for a connection
886 * for which NAT was applied in the forward
887 * direction. Do the reverse NAT.
888 */
889 maniptype = ct->status & IPS_SRC_NAT
890 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
891 else
892 maniptype = ct->status & IPS_SRC_NAT
893 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
894 } else if (ct_action & TCA_CT_ACT_NAT_SRC) {
895 maniptype = NF_NAT_MANIP_SRC;
896 } else if (ct_action & TCA_CT_ACT_NAT_DST) {
897 maniptype = NF_NAT_MANIP_DST;
898 } else {
899 return NF_ACCEPT;
900 }
901
902 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
903 if (err == NF_ACCEPT &&
904 ct->status & IPS_SRC_NAT && ct->status & IPS_DST_NAT) {
905 if (maniptype == NF_NAT_MANIP_SRC)
906 maniptype = NF_NAT_MANIP_DST;
907 else
908 maniptype = NF_NAT_MANIP_SRC;
909
910 err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
911 }
912 return err;
913#else
914 return NF_ACCEPT;
915#endif
916}
917
918static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
919 struct tcf_result *res)
920{
921 struct net *net = dev_net(skb->dev);
922 bool cached, commit, clear, force;
923 enum ip_conntrack_info ctinfo;
924 struct tcf_ct *c = to_ct(a);
925 struct nf_conn *tmpl = NULL;
926 struct nf_hook_state state;
927 int nh_ofs, err, retval;
928 struct tcf_ct_params *p;
929 bool skip_add = false;
930 bool defrag = false;
931 struct nf_conn *ct;
932 u8 family;
933
934 p = rcu_dereference_bh(c->params);
935
936 retval = READ_ONCE(c->tcf_action);
937 commit = p->ct_action & TCA_CT_ACT_COMMIT;
938 clear = p->ct_action & TCA_CT_ACT_CLEAR;
939 force = p->ct_action & TCA_CT_ACT_FORCE;
940 tmpl = p->tmpl;
941
942 tcf_lastuse_update(&c->tcf_tm);
943
944 if (clear) {
945 ct = nf_ct_get(skb, &ctinfo);
946 if (ct) {
947 nf_conntrack_put(&ct->ct_general);
948 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
949 }
950
951 goto out;
952 }
953
954 family = tcf_ct_skb_nf_family(skb);
955 if (family == NFPROTO_UNSPEC)
956 goto drop;
957
958 /* The conntrack module expects to be working at L3.
959 * We also try to pull the IPv4/6 header to linear area
960 */
961 nh_ofs = skb_network_offset(skb);
962 skb_pull_rcsum(skb, nh_ofs);
963 err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
964 if (err == -EINPROGRESS) {
965 retval = TC_ACT_STOLEN;
966 goto out;
967 }
968 if (err)
969 goto drop;
970
971 err = tcf_ct_skb_network_trim(skb, family);
972 if (err)
973 goto drop;
974
975 /* If we are recirculating packets to match on ct fields and
976 * committing with a separate ct action, then we don't need to
977 * actually run the packet through conntrack twice unless it's for a
978 * different zone.
979 */
980 cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);
981 if (!cached) {
982 if (!commit && tcf_ct_flow_table_lookup(p, skb, family)) {
983 skip_add = true;
984 goto do_nat;
985 }
986
987 /* Associate skb with specified zone. */
988 if (tmpl) {
989 ct = nf_ct_get(skb, &ctinfo);
990 if (skb_nfct(skb))
991 nf_conntrack_put(skb_nfct(skb));
992 nf_conntrack_get(&tmpl->ct_general);
993 nf_ct_set(skb, tmpl, IP_CT_NEW);
994 }
995
996 state.hook = NF_INET_PRE_ROUTING;
997 state.net = net;
998 state.pf = family;
999 err = nf_conntrack_in(skb, &state);
1000 if (err != NF_ACCEPT)
1001 goto out_push;
1002 }
1003
1004do_nat:
1005 ct = nf_ct_get(skb, &ctinfo);
1006 if (!ct)
1007 goto out_push;
1008 nf_ct_deliver_cached_events(ct);
1009
1010 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1011 if (err != NF_ACCEPT)
1012 goto drop;
1013
1014 if (commit) {
1015 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1016 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1017
1018 /* This will take care of sending queued events
1019 * even if the connection is already confirmed.
1020 */
1021 nf_conntrack_confirm(skb);
1022 } else if (!skip_add) {
1023 tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1024 }
1025
1026out_push:
1027 skb_push_rcsum(skb, nh_ofs);
1028
1029out:
1030 tcf_action_update_bstats(&c->common, skb);
1031 if (defrag)
1032 qdisc_skb_cb(skb)->pkt_len = skb->len;
1033 return retval;
1034
1035drop:
1036 tcf_action_inc_drop_qstats(&c->common);
1037 return TC_ACT_SHOT;
1038}
1039
1040static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1041 [TCA_CT_ACTION] = { .type = NLA_U16 },
1042 [TCA_CT_PARMS] = { .type = NLA_EXACT_LEN, .len = sizeof(struct tc_ct) },
1043 [TCA_CT_ZONE] = { .type = NLA_U16 },
1044 [TCA_CT_MARK] = { .type = NLA_U32 },
1045 [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1046 [TCA_CT_LABELS] = { .type = NLA_BINARY,
1047 .len = 128 / BITS_PER_BYTE },
1048 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1049 .len = 128 / BITS_PER_BYTE },
1050 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1051 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1052 [TCA_CT_NAT_IPV6_MIN] = { .type = NLA_EXACT_LEN,
1053 .len = sizeof(struct in6_addr) },
1054 [TCA_CT_NAT_IPV6_MAX] = { .type = NLA_EXACT_LEN,
1055 .len = sizeof(struct in6_addr) },
1056 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1057 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1058};
1059
1060static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1061 struct tc_ct *parm,
1062 struct nlattr **tb,
1063 struct netlink_ext_ack *extack)
1064{
1065 struct nf_nat_range2 *range;
1066
1067 if (!(p->ct_action & TCA_CT_ACT_NAT))
1068 return 0;
1069
1070 if (!IS_ENABLED(CONFIG_NF_NAT)) {
1071 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1072 return -EOPNOTSUPP;
1073 }
1074
1075 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1076 return 0;
1077
1078 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1079 (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1080 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1081 return -EOPNOTSUPP;
1082 }
1083
1084 range = &p->range;
1085 if (tb[TCA_CT_NAT_IPV4_MIN]) {
1086 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1087
1088 p->ipv4_range = true;
1089 range->flags |= NF_NAT_RANGE_MAP_IPS;
1090 range->min_addr.ip =
1091 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1092
1093 range->max_addr.ip = max_attr ?
1094 nla_get_in_addr(max_attr) :
1095 range->min_addr.ip;
1096 } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1097 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1098
1099 p->ipv4_range = false;
1100 range->flags |= NF_NAT_RANGE_MAP_IPS;
1101 range->min_addr.in6 =
1102 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1103
1104 range->max_addr.in6 = max_attr ?
1105 nla_get_in6_addr(max_attr) :
1106 range->min_addr.in6;
1107 }
1108
1109 if (tb[TCA_CT_NAT_PORT_MIN]) {
1110 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1111 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1112
1113 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1114 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1115 range->min_proto.all;
1116 }
1117
1118 return 0;
1119}
1120
1121static void tcf_ct_set_key_val(struct nlattr **tb,
1122 void *val, int val_type,
1123 void *mask, int mask_type,
1124 int len)
1125{
1126 if (!tb[val_type])
1127 return;
1128 nla_memcpy(val, tb[val_type], len);
1129
1130 if (!mask)
1131 return;
1132
1133 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1134 memset(mask, 0xff, len);
1135 else
1136 nla_memcpy(mask, tb[mask_type], len);
1137}
1138
1139static int tcf_ct_fill_params(struct net *net,
1140 struct tcf_ct_params *p,
1141 struct tc_ct *parm,
1142 struct nlattr **tb,
1143 struct netlink_ext_ack *extack)
1144{
1145 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1146 struct nf_conntrack_zone zone;
1147 struct nf_conn *tmpl;
1148 int err;
1149
1150 p->zone = NF_CT_DEFAULT_ZONE_ID;
1151
1152 tcf_ct_set_key_val(tb,
1153 &p->ct_action, TCA_CT_ACTION,
1154 NULL, TCA_CT_UNSPEC,
1155 sizeof(p->ct_action));
1156
1157 if (p->ct_action & TCA_CT_ACT_CLEAR)
1158 return 0;
1159
1160 err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1161 if (err)
1162 return err;
1163
1164 if (tb[TCA_CT_MARK]) {
1165 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1166 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1167 return -EOPNOTSUPP;
1168 }
1169 tcf_ct_set_key_val(tb,
1170 &p->mark, TCA_CT_MARK,
1171 &p->mark_mask, TCA_CT_MARK_MASK,
1172 sizeof(p->mark));
1173 }
1174
1175 if (tb[TCA_CT_LABELS]) {
1176 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1177 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1178 return -EOPNOTSUPP;
1179 }
1180
1181 if (!tn->labels) {
1182 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1183 return -EOPNOTSUPP;
1184 }
1185 tcf_ct_set_key_val(tb,
1186 p->labels, TCA_CT_LABELS,
1187 p->labels_mask, TCA_CT_LABELS_MASK,
1188 sizeof(p->labels));
1189 }
1190
1191 if (tb[TCA_CT_ZONE]) {
1192 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1193 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1194 return -EOPNOTSUPP;
1195 }
1196
1197 tcf_ct_set_key_val(tb,
1198 &p->zone, TCA_CT_ZONE,
1199 NULL, TCA_CT_UNSPEC,
1200 sizeof(p->zone));
1201 }
1202
1203 if (p->zone == NF_CT_DEFAULT_ZONE_ID)
1204 return 0;
1205
1206 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1207 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1208 if (!tmpl) {
1209 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1210 return -ENOMEM;
1211 }
1212 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1213 nf_conntrack_get(&tmpl->ct_general);
1214 p->tmpl = tmpl;
1215
1216 return 0;
1217}
1218
1219static int tcf_ct_init(struct net *net, struct nlattr *nla,
1220 struct nlattr *est, struct tc_action **a,
1221 int replace, int bind, bool rtnl_held,
1222 struct tcf_proto *tp, u32 flags,
1223 struct netlink_ext_ack *extack)
1224{
1225 struct tc_action_net *tn = net_generic(net, ct_net_id);
1226 struct tcf_ct_params *params = NULL;
1227 struct nlattr *tb[TCA_CT_MAX + 1];
1228 struct tcf_chain *goto_ch = NULL;
1229 struct tc_ct *parm;
1230 struct tcf_ct *c;
1231 int err, res = 0;
1232 u32 index;
1233
1234 if (!nla) {
1235 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1236 return -EINVAL;
1237 }
1238
1239 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1240 if (err < 0)
1241 return err;
1242
1243 if (!tb[TCA_CT_PARMS]) {
1244 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1245 return -EINVAL;
1246 }
1247 parm = nla_data(tb[TCA_CT_PARMS]);
1248 index = parm->index;
1249 err = tcf_idr_check_alloc(tn, &index, a, bind);
1250 if (err < 0)
1251 return err;
1252
1253 if (!err) {
1254 err = tcf_idr_create_from_flags(tn, index, est, a,
1255 &act_ct_ops, bind, flags);
1256 if (err) {
1257 tcf_idr_cleanup(tn, index);
1258 return err;
1259 }
1260 res = ACT_P_CREATED;
1261 } else {
1262 if (bind)
1263 return 0;
1264
1265 if (!replace) {
1266 tcf_idr_release(*a, bind);
1267 return -EEXIST;
1268 }
1269 }
1270 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1271 if (err < 0)
1272 goto cleanup;
1273
1274 c = to_ct(*a);
1275
1276 params = kzalloc(sizeof(*params), GFP_KERNEL);
1277 if (unlikely(!params)) {
1278 err = -ENOMEM;
1279 goto cleanup;
1280 }
1281
1282 err = tcf_ct_fill_params(net, params, parm, tb, extack);
1283 if (err)
1284 goto cleanup;
1285
1286 err = tcf_ct_flow_table_get(params);
1287 if (err)
1288 goto cleanup;
1289
1290 spin_lock_bh(&c->tcf_lock);
1291 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1292 params = rcu_replace_pointer(c->params, params,
1293 lockdep_is_held(&c->tcf_lock));
1294 spin_unlock_bh(&c->tcf_lock);
1295
1296 if (goto_ch)
1297 tcf_chain_put_by_act(goto_ch);
1298 if (params)
1299 call_rcu(¶ms->rcu, tcf_ct_params_free);
1300
1301 return res;
1302
1303cleanup:
1304 if (goto_ch)
1305 tcf_chain_put_by_act(goto_ch);
1306 kfree(params);
1307 tcf_idr_release(*a, bind);
1308 return err;
1309}
1310
1311static void tcf_ct_cleanup(struct tc_action *a)
1312{
1313 struct tcf_ct_params *params;
1314 struct tcf_ct *c = to_ct(a);
1315
1316 params = rcu_dereference_protected(c->params, 1);
1317 if (params)
1318 call_rcu(¶ms->rcu, tcf_ct_params_free);
1319}
1320
1321static int tcf_ct_dump_key_val(struct sk_buff *skb,
1322 void *val, int val_type,
1323 void *mask, int mask_type,
1324 int len)
1325{
1326 int err;
1327
1328 if (mask && !memchr_inv(mask, 0, len))
1329 return 0;
1330
1331 err = nla_put(skb, val_type, len, val);
1332 if (err)
1333 return err;
1334
1335 if (mask_type != TCA_CT_UNSPEC) {
1336 err = nla_put(skb, mask_type, len, mask);
1337 if (err)
1338 return err;
1339 }
1340
1341 return 0;
1342}
1343
1344static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1345{
1346 struct nf_nat_range2 *range = &p->range;
1347
1348 if (!(p->ct_action & TCA_CT_ACT_NAT))
1349 return 0;
1350
1351 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1352 return 0;
1353
1354 if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1355 if (p->ipv4_range) {
1356 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1357 range->min_addr.ip))
1358 return -1;
1359 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1360 range->max_addr.ip))
1361 return -1;
1362 } else {
1363 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1364 &range->min_addr.in6))
1365 return -1;
1366 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1367 &range->max_addr.in6))
1368 return -1;
1369 }
1370 }
1371
1372 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1373 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1374 range->min_proto.all))
1375 return -1;
1376 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1377 range->max_proto.all))
1378 return -1;
1379 }
1380
1381 return 0;
1382}
1383
1384static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1385 int bind, int ref)
1386{
1387 unsigned char *b = skb_tail_pointer(skb);
1388 struct tcf_ct *c = to_ct(a);
1389 struct tcf_ct_params *p;
1390
1391 struct tc_ct opt = {
1392 .index = c->tcf_index,
1393 .refcnt = refcount_read(&c->tcf_refcnt) - ref,
1394 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1395 };
1396 struct tcf_t t;
1397
1398 spin_lock_bh(&c->tcf_lock);
1399 p = rcu_dereference_protected(c->params,
1400 lockdep_is_held(&c->tcf_lock));
1401 opt.action = c->tcf_action;
1402
1403 if (tcf_ct_dump_key_val(skb,
1404 &p->ct_action, TCA_CT_ACTION,
1405 NULL, TCA_CT_UNSPEC,
1406 sizeof(p->ct_action)))
1407 goto nla_put_failure;
1408
1409 if (p->ct_action & TCA_CT_ACT_CLEAR)
1410 goto skip_dump;
1411
1412 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1413 tcf_ct_dump_key_val(skb,
1414 &p->mark, TCA_CT_MARK,
1415 &p->mark_mask, TCA_CT_MARK_MASK,
1416 sizeof(p->mark)))
1417 goto nla_put_failure;
1418
1419 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1420 tcf_ct_dump_key_val(skb,
1421 p->labels, TCA_CT_LABELS,
1422 p->labels_mask, TCA_CT_LABELS_MASK,
1423 sizeof(p->labels)))
1424 goto nla_put_failure;
1425
1426 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1427 tcf_ct_dump_key_val(skb,
1428 &p->zone, TCA_CT_ZONE,
1429 NULL, TCA_CT_UNSPEC,
1430 sizeof(p->zone)))
1431 goto nla_put_failure;
1432
1433 if (tcf_ct_dump_nat(skb, p))
1434 goto nla_put_failure;
1435
1436skip_dump:
1437 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1438 goto nla_put_failure;
1439
1440 tcf_tm_dump(&t, &c->tcf_tm);
1441 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1442 goto nla_put_failure;
1443 spin_unlock_bh(&c->tcf_lock);
1444
1445 return skb->len;
1446nla_put_failure:
1447 spin_unlock_bh(&c->tcf_lock);
1448 nlmsg_trim(skb, b);
1449 return -1;
1450}
1451
1452static int tcf_ct_walker(struct net *net, struct sk_buff *skb,
1453 struct netlink_callback *cb, int type,
1454 const struct tc_action_ops *ops,
1455 struct netlink_ext_ack *extack)
1456{
1457 struct tc_action_net *tn = net_generic(net, ct_net_id);
1458
1459 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
1460}
1461
1462static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index)
1463{
1464 struct tc_action_net *tn = net_generic(net, ct_net_id);
1465
1466 return tcf_idr_search(tn, a, index);
1467}
1468
1469static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1470 u64 drops, u64 lastuse, bool hw)
1471{
1472 struct tcf_ct *c = to_ct(a);
1473
1474 tcf_action_update_stats(a, bytes, packets, drops, hw);
1475 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1476}
1477
1478static struct tc_action_ops act_ct_ops = {
1479 .kind = "ct",
1480 .id = TCA_ID_CT,
1481 .owner = THIS_MODULE,
1482 .act = tcf_ct_act,
1483 .dump = tcf_ct_dump,
1484 .init = tcf_ct_init,
1485 .cleanup = tcf_ct_cleanup,
1486 .walk = tcf_ct_walker,
1487 .lookup = tcf_ct_search,
1488 .stats_update = tcf_stats_update,
1489 .size = sizeof(struct tcf_ct),
1490};
1491
1492static __net_init int ct_init_net(struct net *net)
1493{
1494 unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1495 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1496
1497 if (nf_connlabels_get(net, n_bits - 1)) {
1498 tn->labels = false;
1499 pr_err("act_ct: Failed to set connlabels length");
1500 } else {
1501 tn->labels = true;
1502 }
1503
1504 return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1505}
1506
1507static void __net_exit ct_exit_net(struct list_head *net_list)
1508{
1509 struct net *net;
1510
1511 rtnl_lock();
1512 list_for_each_entry(net, net_list, exit_list) {
1513 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1514
1515 if (tn->labels)
1516 nf_connlabels_put(net);
1517 }
1518 rtnl_unlock();
1519
1520 tc_action_net_exit(net_list, ct_net_id);
1521}
1522
1523static struct pernet_operations ct_net_ops = {
1524 .init = ct_init_net,
1525 .exit_batch = ct_exit_net,
1526 .id = &ct_net_id,
1527 .size = sizeof(struct tc_ct_action_net),
1528};
1529
1530static int __init ct_init_module(void)
1531{
1532 int err;
1533
1534 act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1535 if (!act_ct_wq)
1536 return -ENOMEM;
1537
1538 err = tcf_ct_flow_tables_init();
1539 if (err)
1540 goto err_tbl_init;
1541
1542 err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1543 if (err)
1544 goto err_register;
1545
1546 return 0;
1547
1548err_register:
1549 tcf_ct_flow_tables_uninit();
1550err_tbl_init:
1551 destroy_workqueue(act_ct_wq);
1552 return err;
1553}
1554
1555static void __exit ct_cleanup_module(void)
1556{
1557 tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1558 tcf_ct_flow_tables_uninit();
1559 destroy_workqueue(act_ct_wq);
1560}
1561
1562module_init(ct_init_module);
1563module_exit(ct_cleanup_module);
1564MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1565MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1566MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1567MODULE_DESCRIPTION("Connection tracking action");
1568MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2/* -
3 * net/sched/act_ct.c Connection Tracking action
4 *
5 * Authors: Paul Blakey <paulb@mellanox.com>
6 * Yossi Kuperman <yossiku@mellanox.com>
7 * Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
8 */
9
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/kernel.h>
13#include <linux/skbuff.h>
14#include <linux/rtnetlink.h>
15#include <linux/pkt_cls.h>
16#include <linux/ip.h>
17#include <linux/ipv6.h>
18#include <net/netlink.h>
19#include <net/pkt_sched.h>
20#include <net/pkt_cls.h>
21#include <net/act_api.h>
22#include <net/ip.h>
23#include <net/ipv6_frag.h>
24#include <uapi/linux/tc_act/tc_ct.h>
25#include <net/tc_act/tc_ct.h>
26
27#include <net/netfilter/nf_conntrack.h>
28#include <net/netfilter/nf_conntrack_core.h>
29#include <net/netfilter/nf_conntrack_zones.h>
30#include <net/netfilter/nf_conntrack_helper.h>
31#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
32#include <uapi/linux/netfilter/nf_nat.h>
33
34static struct tc_action_ops act_ct_ops;
35static unsigned int ct_net_id;
36
37struct tc_ct_action_net {
38 struct tc_action_net tn; /* Must be first */
39 bool labels;
40};
41
42/* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
43static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
44 u16 zone_id, bool force)
45{
46 enum ip_conntrack_info ctinfo;
47 struct nf_conn *ct;
48
49 ct = nf_ct_get(skb, &ctinfo);
50 if (!ct)
51 return false;
52 if (!net_eq(net, read_pnet(&ct->ct_net)))
53 return false;
54 if (nf_ct_zone(ct)->id != zone_id)
55 return false;
56
57 /* Force conntrack entry direction. */
58 if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
59 if (nf_ct_is_confirmed(ct))
60 nf_ct_kill(ct);
61
62 nf_conntrack_put(&ct->ct_general);
63 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
64
65 return false;
66 }
67
68 return true;
69}
70
71/* Trim the skb to the length specified by the IP/IPv6 header,
72 * removing any trailing lower-layer padding. This prepares the skb
73 * for higher-layer processing that assumes skb->len excludes padding
74 * (such as nf_ip_checksum). The caller needs to pull the skb to the
75 * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
76 */
77static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
78{
79 unsigned int len;
80 int err;
81
82 switch (family) {
83 case NFPROTO_IPV4:
84 len = ntohs(ip_hdr(skb)->tot_len);
85 break;
86 case NFPROTO_IPV6:
87 len = sizeof(struct ipv6hdr)
88 + ntohs(ipv6_hdr(skb)->payload_len);
89 break;
90 default:
91 len = skb->len;
92 }
93
94 err = pskb_trim_rcsum(skb, len);
95
96 return err;
97}
98
99static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
100{
101 u8 family = NFPROTO_UNSPEC;
102
103 switch (skb->protocol) {
104 case htons(ETH_P_IP):
105 family = NFPROTO_IPV4;
106 break;
107 case htons(ETH_P_IPV6):
108 family = NFPROTO_IPV6;
109 break;
110 default:
111 break;
112 }
113
114 return family;
115}
116
117static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
118{
119 unsigned int len;
120
121 len = skb_network_offset(skb) + sizeof(struct iphdr);
122 if (unlikely(skb->len < len))
123 return -EINVAL;
124 if (unlikely(!pskb_may_pull(skb, len)))
125 return -ENOMEM;
126
127 *frag = ip_is_fragment(ip_hdr(skb));
128 return 0;
129}
130
131static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
132{
133 unsigned int flags = 0, len, payload_ofs = 0;
134 unsigned short frag_off;
135 int nexthdr;
136
137 len = skb_network_offset(skb) + sizeof(struct ipv6hdr);
138 if (unlikely(skb->len < len))
139 return -EINVAL;
140 if (unlikely(!pskb_may_pull(skb, len)))
141 return -ENOMEM;
142
143 nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
144 if (unlikely(nexthdr < 0))
145 return -EPROTO;
146
147 *frag = flags & IP6_FH_F_FRAG;
148 return 0;
149}
150
151static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
152 u8 family, u16 zone)
153{
154 enum ip_conntrack_info ctinfo;
155 struct nf_conn *ct;
156 int err = 0;
157 bool frag;
158
159 /* Previously seen (loopback)? Ignore. */
160 ct = nf_ct_get(skb, &ctinfo);
161 if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
162 return 0;
163
164 if (family == NFPROTO_IPV4)
165 err = tcf_ct_ipv4_is_fragment(skb, &frag);
166 else
167 err = tcf_ct_ipv6_is_fragment(skb, &frag);
168 if (err || !frag)
169 return err;
170
171 skb_get(skb);
172
173 if (family == NFPROTO_IPV4) {
174 enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
175
176 memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
177 local_bh_disable();
178 err = ip_defrag(net, skb, user);
179 local_bh_enable();
180 if (err && err != -EINPROGRESS)
181 goto out_free;
182 } else { /* NFPROTO_IPV6 */
183#if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
184 enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
185
186 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
187 err = nf_ct_frag6_gather(net, skb, user);
188 if (err && err != -EINPROGRESS)
189 goto out_free;
190#else
191 err = -EOPNOTSUPP;
192 goto out_free;
193#endif
194 }
195
196 skb_clear_hash(skb);
197 skb->ignore_df = 1;
198 return err;
199
200out_free:
201 kfree_skb(skb);
202 return err;
203}
204
205static void tcf_ct_params_free(struct rcu_head *head)
206{
207 struct tcf_ct_params *params = container_of(head,
208 struct tcf_ct_params, rcu);
209
210 if (params->tmpl)
211 nf_conntrack_put(¶ms->tmpl->ct_general);
212 kfree(params);
213}
214
215#if IS_ENABLED(CONFIG_NF_NAT)
216/* Modelled after nf_nat_ipv[46]_fn().
217 * range is only used for new, uninitialized NAT state.
218 * Returns either NF_ACCEPT or NF_DROP.
219 */
220static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
221 enum ip_conntrack_info ctinfo,
222 const struct nf_nat_range2 *range,
223 enum nf_nat_manip_type maniptype)
224{
225 int hooknum, err = NF_ACCEPT;
226
227 /* See HOOK2MANIP(). */
228 if (maniptype == NF_NAT_MANIP_SRC)
229 hooknum = NF_INET_LOCAL_IN; /* Source NAT */
230 else
231 hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
232
233 switch (ctinfo) {
234 case IP_CT_RELATED:
235 case IP_CT_RELATED_REPLY:
236 if (skb->protocol == htons(ETH_P_IP) &&
237 ip_hdr(skb)->protocol == IPPROTO_ICMP) {
238 if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
239 hooknum))
240 err = NF_DROP;
241 goto out;
242 } else if (IS_ENABLED(CONFIG_IPV6) &&
243 skb->protocol == htons(ETH_P_IPV6)) {
244 __be16 frag_off;
245 u8 nexthdr = ipv6_hdr(skb)->nexthdr;
246 int hdrlen = ipv6_skip_exthdr(skb,
247 sizeof(struct ipv6hdr),
248 &nexthdr, &frag_off);
249
250 if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
251 if (!nf_nat_icmpv6_reply_translation(skb, ct,
252 ctinfo,
253 hooknum,
254 hdrlen))
255 err = NF_DROP;
256 goto out;
257 }
258 }
259 /* Non-ICMP, fall thru to initialize if needed. */
260 /* fall through */
261 case IP_CT_NEW:
262 /* Seen it before? This can happen for loopback, retrans,
263 * or local packets.
264 */
265 if (!nf_nat_initialized(ct, maniptype)) {
266 /* Initialize according to the NAT action. */
267 err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
268 /* Action is set up to establish a new
269 * mapping.
270 */
271 ? nf_nat_setup_info(ct, range, maniptype)
272 : nf_nat_alloc_null_binding(ct, hooknum);
273 if (err != NF_ACCEPT)
274 goto out;
275 }
276 break;
277
278 case IP_CT_ESTABLISHED:
279 case IP_CT_ESTABLISHED_REPLY:
280 break;
281
282 default:
283 err = NF_DROP;
284 goto out;
285 }
286
287 err = nf_nat_packet(ct, ctinfo, hooknum, skb);
288out:
289 return err;
290}
291#endif /* CONFIG_NF_NAT */
292
293static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
294{
295#if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
296 u32 new_mark;
297
298 if (!mask)
299 return;
300
301 new_mark = mark | (ct->mark & ~(mask));
302 if (ct->mark != new_mark) {
303 ct->mark = new_mark;
304 if (nf_ct_is_confirmed(ct))
305 nf_conntrack_event_cache(IPCT_MARK, ct);
306 }
307#endif
308}
309
310static void tcf_ct_act_set_labels(struct nf_conn *ct,
311 u32 *labels,
312 u32 *labels_m)
313{
314#if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
315 size_t labels_sz = FIELD_SIZEOF(struct tcf_ct_params, labels);
316
317 if (!memchr_inv(labels_m, 0, labels_sz))
318 return;
319
320 nf_connlabels_replace(ct, labels, labels_m, 4);
321#endif
322}
323
324static int tcf_ct_act_nat(struct sk_buff *skb,
325 struct nf_conn *ct,
326 enum ip_conntrack_info ctinfo,
327 int ct_action,
328 struct nf_nat_range2 *range,
329 bool commit)
330{
331#if IS_ENABLED(CONFIG_NF_NAT)
332 enum nf_nat_manip_type maniptype;
333
334 if (!(ct_action & TCA_CT_ACT_NAT))
335 return NF_ACCEPT;
336
337 /* Add NAT extension if not confirmed yet. */
338 if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
339 return NF_DROP; /* Can't NAT. */
340
341 if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) &&
342 (ctinfo != IP_CT_RELATED || commit)) {
343 /* NAT an established or related connection like before. */
344 if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
345 /* This is the REPLY direction for a connection
346 * for which NAT was applied in the forward
347 * direction. Do the reverse NAT.
348 */
349 maniptype = ct->status & IPS_SRC_NAT
350 ? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
351 else
352 maniptype = ct->status & IPS_SRC_NAT
353 ? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
354 } else if (ct_action & TCA_CT_ACT_NAT_SRC) {
355 maniptype = NF_NAT_MANIP_SRC;
356 } else if (ct_action & TCA_CT_ACT_NAT_DST) {
357 maniptype = NF_NAT_MANIP_DST;
358 } else {
359 return NF_ACCEPT;
360 }
361
362 return ct_nat_execute(skb, ct, ctinfo, range, maniptype);
363#else
364 return NF_ACCEPT;
365#endif
366}
367
368static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
369 struct tcf_result *res)
370{
371 struct net *net = dev_net(skb->dev);
372 bool cached, commit, clear, force;
373 enum ip_conntrack_info ctinfo;
374 struct tcf_ct *c = to_ct(a);
375 struct nf_conn *tmpl = NULL;
376 struct nf_hook_state state;
377 int nh_ofs, err, retval;
378 struct tcf_ct_params *p;
379 struct nf_conn *ct;
380 u8 family;
381
382 p = rcu_dereference_bh(c->params);
383
384 retval = READ_ONCE(c->tcf_action);
385 commit = p->ct_action & TCA_CT_ACT_COMMIT;
386 clear = p->ct_action & TCA_CT_ACT_CLEAR;
387 force = p->ct_action & TCA_CT_ACT_FORCE;
388 tmpl = p->tmpl;
389
390 if (clear) {
391 ct = nf_ct_get(skb, &ctinfo);
392 if (ct) {
393 nf_conntrack_put(&ct->ct_general);
394 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
395 }
396
397 goto out;
398 }
399
400 family = tcf_ct_skb_nf_family(skb);
401 if (family == NFPROTO_UNSPEC)
402 goto drop;
403
404 /* The conntrack module expects to be working at L3.
405 * We also try to pull the IPv4/6 header to linear area
406 */
407 nh_ofs = skb_network_offset(skb);
408 skb_pull_rcsum(skb, nh_ofs);
409 err = tcf_ct_handle_fragments(net, skb, family, p->zone);
410 if (err == -EINPROGRESS) {
411 retval = TC_ACT_STOLEN;
412 goto out;
413 }
414 if (err)
415 goto drop;
416
417 err = tcf_ct_skb_network_trim(skb, family);
418 if (err)
419 goto drop;
420
421 /* If we are recirculating packets to match on ct fields and
422 * committing with a separate ct action, then we don't need to
423 * actually run the packet through conntrack twice unless it's for a
424 * different zone.
425 */
426 cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);
427 if (!cached) {
428 /* Associate skb with specified zone. */
429 if (tmpl) {
430 ct = nf_ct_get(skb, &ctinfo);
431 if (skb_nfct(skb))
432 nf_conntrack_put(skb_nfct(skb));
433 nf_conntrack_get(&tmpl->ct_general);
434 nf_ct_set(skb, tmpl, IP_CT_NEW);
435 }
436
437 state.hook = NF_INET_PRE_ROUTING;
438 state.net = net;
439 state.pf = family;
440 err = nf_conntrack_in(skb, &state);
441 if (err != NF_ACCEPT)
442 goto out_push;
443 }
444
445 ct = nf_ct_get(skb, &ctinfo);
446 if (!ct)
447 goto out_push;
448 nf_ct_deliver_cached_events(ct);
449
450 err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
451 if (err != NF_ACCEPT)
452 goto drop;
453
454 if (commit) {
455 tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
456 tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
457
458 /* This will take care of sending queued events
459 * even if the connection is already confirmed.
460 */
461 nf_conntrack_confirm(skb);
462 }
463
464out_push:
465 skb_push_rcsum(skb, nh_ofs);
466
467out:
468 bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), skb);
469 return retval;
470
471drop:
472 qstats_drop_inc(this_cpu_ptr(a->cpu_qstats));
473 return TC_ACT_SHOT;
474}
475
476static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
477 [TCA_CT_UNSPEC] = { .strict_start_type = TCA_CT_UNSPEC + 1 },
478 [TCA_CT_ACTION] = { .type = NLA_U16 },
479 [TCA_CT_PARMS] = { .type = NLA_EXACT_LEN, .len = sizeof(struct tc_ct) },
480 [TCA_CT_ZONE] = { .type = NLA_U16 },
481 [TCA_CT_MARK] = { .type = NLA_U32 },
482 [TCA_CT_MARK_MASK] = { .type = NLA_U32 },
483 [TCA_CT_LABELS] = { .type = NLA_BINARY,
484 .len = 128 / BITS_PER_BYTE },
485 [TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
486 .len = 128 / BITS_PER_BYTE },
487 [TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
488 [TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
489 [TCA_CT_NAT_IPV6_MIN] = { .type = NLA_EXACT_LEN,
490 .len = sizeof(struct in6_addr) },
491 [TCA_CT_NAT_IPV6_MAX] = { .type = NLA_EXACT_LEN,
492 .len = sizeof(struct in6_addr) },
493 [TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
494 [TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
495};
496
497static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
498 struct tc_ct *parm,
499 struct nlattr **tb,
500 struct netlink_ext_ack *extack)
501{
502 struct nf_nat_range2 *range;
503
504 if (!(p->ct_action & TCA_CT_ACT_NAT))
505 return 0;
506
507 if (!IS_ENABLED(CONFIG_NF_NAT)) {
508 NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
509 return -EOPNOTSUPP;
510 }
511
512 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
513 return 0;
514
515 if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
516 (p->ct_action & TCA_CT_ACT_NAT_DST)) {
517 NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
518 return -EOPNOTSUPP;
519 }
520
521 range = &p->range;
522 if (tb[TCA_CT_NAT_IPV4_MIN]) {
523 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
524
525 p->ipv4_range = true;
526 range->flags |= NF_NAT_RANGE_MAP_IPS;
527 range->min_addr.ip =
528 nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
529
530 range->max_addr.ip = max_attr ?
531 nla_get_in_addr(max_attr) :
532 range->min_addr.ip;
533 } else if (tb[TCA_CT_NAT_IPV6_MIN]) {
534 struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
535
536 p->ipv4_range = false;
537 range->flags |= NF_NAT_RANGE_MAP_IPS;
538 range->min_addr.in6 =
539 nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
540
541 range->max_addr.in6 = max_attr ?
542 nla_get_in6_addr(max_attr) :
543 range->min_addr.in6;
544 }
545
546 if (tb[TCA_CT_NAT_PORT_MIN]) {
547 range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
548 range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
549
550 range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
551 nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
552 range->min_proto.all;
553 }
554
555 return 0;
556}
557
558static void tcf_ct_set_key_val(struct nlattr **tb,
559 void *val, int val_type,
560 void *mask, int mask_type,
561 int len)
562{
563 if (!tb[val_type])
564 return;
565 nla_memcpy(val, tb[val_type], len);
566
567 if (!mask)
568 return;
569
570 if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
571 memset(mask, 0xff, len);
572 else
573 nla_memcpy(mask, tb[mask_type], len);
574}
575
576static int tcf_ct_fill_params(struct net *net,
577 struct tcf_ct_params *p,
578 struct tc_ct *parm,
579 struct nlattr **tb,
580 struct netlink_ext_ack *extack)
581{
582 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
583 struct nf_conntrack_zone zone;
584 struct nf_conn *tmpl;
585 int err;
586
587 p->zone = NF_CT_DEFAULT_ZONE_ID;
588
589 tcf_ct_set_key_val(tb,
590 &p->ct_action, TCA_CT_ACTION,
591 NULL, TCA_CT_UNSPEC,
592 sizeof(p->ct_action));
593
594 if (p->ct_action & TCA_CT_ACT_CLEAR)
595 return 0;
596
597 err = tcf_ct_fill_params_nat(p, parm, tb, extack);
598 if (err)
599 return err;
600
601 if (tb[TCA_CT_MARK]) {
602 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
603 NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
604 return -EOPNOTSUPP;
605 }
606 tcf_ct_set_key_val(tb,
607 &p->mark, TCA_CT_MARK,
608 &p->mark_mask, TCA_CT_MARK_MASK,
609 sizeof(p->mark));
610 }
611
612 if (tb[TCA_CT_LABELS]) {
613 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
614 NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
615 return -EOPNOTSUPP;
616 }
617
618 if (!tn->labels) {
619 NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
620 return -EOPNOTSUPP;
621 }
622 tcf_ct_set_key_val(tb,
623 p->labels, TCA_CT_LABELS,
624 p->labels_mask, TCA_CT_LABELS_MASK,
625 sizeof(p->labels));
626 }
627
628 if (tb[TCA_CT_ZONE]) {
629 if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
630 NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
631 return -EOPNOTSUPP;
632 }
633
634 tcf_ct_set_key_val(tb,
635 &p->zone, TCA_CT_ZONE,
636 NULL, TCA_CT_UNSPEC,
637 sizeof(p->zone));
638 }
639
640 if (p->zone == NF_CT_DEFAULT_ZONE_ID)
641 return 0;
642
643 nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
644 tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
645 if (!tmpl) {
646 NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
647 return -ENOMEM;
648 }
649 __set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
650 nf_conntrack_get(&tmpl->ct_general);
651 p->tmpl = tmpl;
652
653 return 0;
654}
655
656static int tcf_ct_init(struct net *net, struct nlattr *nla,
657 struct nlattr *est, struct tc_action **a,
658 int replace, int bind, bool rtnl_held,
659 struct tcf_proto *tp,
660 struct netlink_ext_ack *extack)
661{
662 struct tc_action_net *tn = net_generic(net, ct_net_id);
663 struct tcf_ct_params *params = NULL;
664 struct nlattr *tb[TCA_CT_MAX + 1];
665 struct tcf_chain *goto_ch = NULL;
666 struct tc_ct *parm;
667 struct tcf_ct *c;
668 int err, res = 0;
669 u32 index;
670
671 if (!nla) {
672 NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
673 return -EINVAL;
674 }
675
676 err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
677 if (err < 0)
678 return err;
679
680 if (!tb[TCA_CT_PARMS]) {
681 NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
682 return -EINVAL;
683 }
684 parm = nla_data(tb[TCA_CT_PARMS]);
685 index = parm->index;
686 err = tcf_idr_check_alloc(tn, &index, a, bind);
687 if (err < 0)
688 return err;
689
690 if (!err) {
691 err = tcf_idr_create(tn, index, est, a,
692 &act_ct_ops, bind, true);
693 if (err) {
694 tcf_idr_cleanup(tn, index);
695 return err;
696 }
697 res = ACT_P_CREATED;
698 } else {
699 if (bind)
700 return 0;
701
702 if (!replace) {
703 tcf_idr_release(*a, bind);
704 return -EEXIST;
705 }
706 }
707 err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
708 if (err < 0)
709 goto cleanup;
710
711 c = to_ct(*a);
712
713 params = kzalloc(sizeof(*params), GFP_KERNEL);
714 if (unlikely(!params)) {
715 err = -ENOMEM;
716 goto cleanup;
717 }
718
719 err = tcf_ct_fill_params(net, params, parm, tb, extack);
720 if (err)
721 goto cleanup;
722
723 spin_lock_bh(&c->tcf_lock);
724 goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
725 rcu_swap_protected(c->params, params, lockdep_is_held(&c->tcf_lock));
726 spin_unlock_bh(&c->tcf_lock);
727
728 if (goto_ch)
729 tcf_chain_put_by_act(goto_ch);
730 if (params)
731 kfree_rcu(params, rcu);
732 if (res == ACT_P_CREATED)
733 tcf_idr_insert(tn, *a);
734
735 return res;
736
737cleanup:
738 if (goto_ch)
739 tcf_chain_put_by_act(goto_ch);
740 kfree(params);
741 tcf_idr_release(*a, bind);
742 return err;
743}
744
745static void tcf_ct_cleanup(struct tc_action *a)
746{
747 struct tcf_ct_params *params;
748 struct tcf_ct *c = to_ct(a);
749
750 params = rcu_dereference_protected(c->params, 1);
751 if (params)
752 call_rcu(¶ms->rcu, tcf_ct_params_free);
753}
754
755static int tcf_ct_dump_key_val(struct sk_buff *skb,
756 void *val, int val_type,
757 void *mask, int mask_type,
758 int len)
759{
760 int err;
761
762 if (mask && !memchr_inv(mask, 0, len))
763 return 0;
764
765 err = nla_put(skb, val_type, len, val);
766 if (err)
767 return err;
768
769 if (mask_type != TCA_CT_UNSPEC) {
770 err = nla_put(skb, mask_type, len, mask);
771 if (err)
772 return err;
773 }
774
775 return 0;
776}
777
778static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
779{
780 struct nf_nat_range2 *range = &p->range;
781
782 if (!(p->ct_action & TCA_CT_ACT_NAT))
783 return 0;
784
785 if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
786 return 0;
787
788 if (range->flags & NF_NAT_RANGE_MAP_IPS) {
789 if (p->ipv4_range) {
790 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
791 range->min_addr.ip))
792 return -1;
793 if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
794 range->max_addr.ip))
795 return -1;
796 } else {
797 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
798 &range->min_addr.in6))
799 return -1;
800 if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
801 &range->max_addr.in6))
802 return -1;
803 }
804 }
805
806 if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
807 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
808 range->min_proto.all))
809 return -1;
810 if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
811 range->max_proto.all))
812 return -1;
813 }
814
815 return 0;
816}
817
818static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
819 int bind, int ref)
820{
821 unsigned char *b = skb_tail_pointer(skb);
822 struct tcf_ct *c = to_ct(a);
823 struct tcf_ct_params *p;
824
825 struct tc_ct opt = {
826 .index = c->tcf_index,
827 .refcnt = refcount_read(&c->tcf_refcnt) - ref,
828 .bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
829 };
830 struct tcf_t t;
831
832 spin_lock_bh(&c->tcf_lock);
833 p = rcu_dereference_protected(c->params,
834 lockdep_is_held(&c->tcf_lock));
835 opt.action = c->tcf_action;
836
837 if (tcf_ct_dump_key_val(skb,
838 &p->ct_action, TCA_CT_ACTION,
839 NULL, TCA_CT_UNSPEC,
840 sizeof(p->ct_action)))
841 goto nla_put_failure;
842
843 if (p->ct_action & TCA_CT_ACT_CLEAR)
844 goto skip_dump;
845
846 if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
847 tcf_ct_dump_key_val(skb,
848 &p->mark, TCA_CT_MARK,
849 &p->mark_mask, TCA_CT_MARK_MASK,
850 sizeof(p->mark)))
851 goto nla_put_failure;
852
853 if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
854 tcf_ct_dump_key_val(skb,
855 p->labels, TCA_CT_LABELS,
856 p->labels_mask, TCA_CT_LABELS_MASK,
857 sizeof(p->labels)))
858 goto nla_put_failure;
859
860 if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
861 tcf_ct_dump_key_val(skb,
862 &p->zone, TCA_CT_ZONE,
863 NULL, TCA_CT_UNSPEC,
864 sizeof(p->zone)))
865 goto nla_put_failure;
866
867 if (tcf_ct_dump_nat(skb, p))
868 goto nla_put_failure;
869
870skip_dump:
871 if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
872 goto nla_put_failure;
873
874 tcf_tm_dump(&t, &c->tcf_tm);
875 if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
876 goto nla_put_failure;
877 spin_unlock_bh(&c->tcf_lock);
878
879 return skb->len;
880nla_put_failure:
881 spin_unlock_bh(&c->tcf_lock);
882 nlmsg_trim(skb, b);
883 return -1;
884}
885
886static int tcf_ct_walker(struct net *net, struct sk_buff *skb,
887 struct netlink_callback *cb, int type,
888 const struct tc_action_ops *ops,
889 struct netlink_ext_ack *extack)
890{
891 struct tc_action_net *tn = net_generic(net, ct_net_id);
892
893 return tcf_generic_walker(tn, skb, cb, type, ops, extack);
894}
895
896static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index)
897{
898 struct tc_action_net *tn = net_generic(net, ct_net_id);
899
900 return tcf_idr_search(tn, a, index);
901}
902
903static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets,
904 u64 lastuse, bool hw)
905{
906 struct tcf_ct *c = to_ct(a);
907
908 _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats), bytes, packets);
909
910 if (hw)
911 _bstats_cpu_update(this_cpu_ptr(a->cpu_bstats_hw),
912 bytes, packets);
913 c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
914}
915
916static struct tc_action_ops act_ct_ops = {
917 .kind = "ct",
918 .id = TCA_ID_CT,
919 .owner = THIS_MODULE,
920 .act = tcf_ct_act,
921 .dump = tcf_ct_dump,
922 .init = tcf_ct_init,
923 .cleanup = tcf_ct_cleanup,
924 .walk = tcf_ct_walker,
925 .lookup = tcf_ct_search,
926 .stats_update = tcf_stats_update,
927 .size = sizeof(struct tcf_ct),
928};
929
930static __net_init int ct_init_net(struct net *net)
931{
932 unsigned int n_bits = FIELD_SIZEOF(struct tcf_ct_params, labels) * 8;
933 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
934
935 if (nf_connlabels_get(net, n_bits - 1)) {
936 tn->labels = false;
937 pr_err("act_ct: Failed to set connlabels length");
938 } else {
939 tn->labels = true;
940 }
941
942 return tc_action_net_init(net, &tn->tn, &act_ct_ops);
943}
944
945static void __net_exit ct_exit_net(struct list_head *net_list)
946{
947 struct net *net;
948
949 rtnl_lock();
950 list_for_each_entry(net, net_list, exit_list) {
951 struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
952
953 if (tn->labels)
954 nf_connlabels_put(net);
955 }
956 rtnl_unlock();
957
958 tc_action_net_exit(net_list, ct_net_id);
959}
960
961static struct pernet_operations ct_net_ops = {
962 .init = ct_init_net,
963 .exit_batch = ct_exit_net,
964 .id = &ct_net_id,
965 .size = sizeof(struct tc_ct_action_net),
966};
967
968static int __init ct_init_module(void)
969{
970 return tcf_register_action(&act_ct_ops, &ct_net_ops);
971}
972
973static void __exit ct_cleanup_module(void)
974{
975 tcf_unregister_action(&act_ct_ops, &ct_net_ops);
976}
977
978module_init(ct_init_module);
979module_exit(ct_cleanup_module);
980MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
981MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
982MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
983MODULE_DESCRIPTION("Connection tracking action");
984MODULE_LICENSE("GPL v2");
985