xref: /openbmc/linux/net/sched/act_ct.c (revision a31edb20)
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 
37 static struct workqueue_struct *act_ct_wq;
38 static struct rhashtable zones_ht;
39 static DEFINE_MUTEX(zones_mutex);
40 
41 struct 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 
52 static 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 
59 static struct flow_action_entry *
60 tcf_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 
67 static 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  */
87 static void
88 tcf_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 
104 static void
105 tcf_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 
117 static void
118 tcf_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 
132 static void
133 tcf_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 
150 static void
151 tcf_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 
168 static 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 
195 static 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 
235 static 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 
264 err_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 
273 static struct nf_flowtable_type flowtable_ct = {
274 	.action		= tcf_ct_flow_table_fill_actions,
275 	.owner		= THIS_MODULE,
276 };
277 
278 static 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, &params->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);
305 out_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 
312 err_init:
313 	rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
314 err_insert:
315 	kfree(ct_ft);
316 err_alloc:
317 	mutex_unlock(&zones_mutex);
318 	return err;
319 }
320 
321 static 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 
333 static 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(&params->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 
344 static 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 
371 err_add:
372 	flow_offload_free(entry);
373 err_alloc:
374 	clear_bit(IPS_OFFLOAD_BIT, &ct->status);
375 }
376 
377 static 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 
405 static bool
406 tcf_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 
451 static bool
452 tcf_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 
493 static 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 
548 static int tcf_ct_flow_tables_init(void)
549 {
550 	return rhashtable_init(&zones_ht, &zones_params);
551 }
552 
553 static void tcf_ct_flow_tables_uninit(void)
554 {
555 	rhashtable_destroy(&zones_ht);
556 }
557 
558 static struct tc_action_ops act_ct_ops;
559 static unsigned int ct_net_id;
560 
561 struct 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. */
567 static 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  */
601 static 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 
623 static 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 
641 static 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 
655 static 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 
675 static 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 			goto out_free;
708 
709 		if (!err)
710 			*defrag = true;
711 	} else { /* NFPROTO_IPV6 */
712 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
713 		enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
714 
715 		memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
716 		err = nf_ct_frag6_gather(net, skb, user);
717 		if (err && err != -EINPROGRESS)
718 			goto out_free;
719 
720 		if (!err)
721 			*defrag = true;
722 #else
723 		err = -EOPNOTSUPP;
724 		goto out_free;
725 #endif
726 	}
727 
728 	*qdisc_skb_cb(skb) = cb;
729 	skb_clear_hash(skb);
730 	skb->ignore_df = 1;
731 	return err;
732 
733 out_free:
734 	kfree_skb(skb);
735 	return err;
736 }
737 
738 static void tcf_ct_params_free(struct rcu_head *head)
739 {
740 	struct tcf_ct_params *params = container_of(head,
741 						    struct tcf_ct_params, rcu);
742 
743 	tcf_ct_flow_table_put(params);
744 
745 	if (params->tmpl)
746 		nf_conntrack_put(&params->tmpl->ct_general);
747 	kfree(params);
748 }
749 
750 #if IS_ENABLED(CONFIG_NF_NAT)
751 /* Modelled after nf_nat_ipv[46]_fn().
752  * range is only used for new, uninitialized NAT state.
753  * Returns either NF_ACCEPT or NF_DROP.
754  */
755 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
756 			  enum ip_conntrack_info ctinfo,
757 			  const struct nf_nat_range2 *range,
758 			  enum nf_nat_manip_type maniptype)
759 {
760 	__be16 proto = skb_protocol(skb, true);
761 	int hooknum, err = NF_ACCEPT;
762 
763 	/* See HOOK2MANIP(). */
764 	if (maniptype == NF_NAT_MANIP_SRC)
765 		hooknum = NF_INET_LOCAL_IN; /* Source NAT */
766 	else
767 		hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
768 
769 	switch (ctinfo) {
770 	case IP_CT_RELATED:
771 	case IP_CT_RELATED_REPLY:
772 		if (proto == htons(ETH_P_IP) &&
773 		    ip_hdr(skb)->protocol == IPPROTO_ICMP) {
774 			if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
775 							   hooknum))
776 				err = NF_DROP;
777 			goto out;
778 		} else if (IS_ENABLED(CONFIG_IPV6) && proto == htons(ETH_P_IPV6)) {
779 			__be16 frag_off;
780 			u8 nexthdr = ipv6_hdr(skb)->nexthdr;
781 			int hdrlen = ipv6_skip_exthdr(skb,
782 						      sizeof(struct ipv6hdr),
783 						      &nexthdr, &frag_off);
784 
785 			if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
786 				if (!nf_nat_icmpv6_reply_translation(skb, ct,
787 								     ctinfo,
788 								     hooknum,
789 								     hdrlen))
790 					err = NF_DROP;
791 				goto out;
792 			}
793 		}
794 		/* Non-ICMP, fall thru to initialize if needed. */
795 		fallthrough;
796 	case IP_CT_NEW:
797 		/* Seen it before?  This can happen for loopback, retrans,
798 		 * or local packets.
799 		 */
800 		if (!nf_nat_initialized(ct, maniptype)) {
801 			/* Initialize according to the NAT action. */
802 			err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
803 				/* Action is set up to establish a new
804 				 * mapping.
805 				 */
806 				? nf_nat_setup_info(ct, range, maniptype)
807 				: nf_nat_alloc_null_binding(ct, hooknum);
808 			if (err != NF_ACCEPT)
809 				goto out;
810 		}
811 		break;
812 
813 	case IP_CT_ESTABLISHED:
814 	case IP_CT_ESTABLISHED_REPLY:
815 		break;
816 
817 	default:
818 		err = NF_DROP;
819 		goto out;
820 	}
821 
822 	err = nf_nat_packet(ct, ctinfo, hooknum, skb);
823 out:
824 	return err;
825 }
826 #endif /* CONFIG_NF_NAT */
827 
828 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
829 {
830 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
831 	u32 new_mark;
832 
833 	if (!mask)
834 		return;
835 
836 	new_mark = mark | (ct->mark & ~(mask));
837 	if (ct->mark != new_mark) {
838 		ct->mark = new_mark;
839 		if (nf_ct_is_confirmed(ct))
840 			nf_conntrack_event_cache(IPCT_MARK, ct);
841 	}
842 #endif
843 }
844 
845 static void tcf_ct_act_set_labels(struct nf_conn *ct,
846 				  u32 *labels,
847 				  u32 *labels_m)
848 {
849 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
850 	size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
851 
852 	if (!memchr_inv(labels_m, 0, labels_sz))
853 		return;
854 
855 	nf_connlabels_replace(ct, labels, labels_m, 4);
856 #endif
857 }
858 
859 static int tcf_ct_act_nat(struct sk_buff *skb,
860 			  struct nf_conn *ct,
861 			  enum ip_conntrack_info ctinfo,
862 			  int ct_action,
863 			  struct nf_nat_range2 *range,
864 			  bool commit)
865 {
866 #if IS_ENABLED(CONFIG_NF_NAT)
867 	int err;
868 	enum nf_nat_manip_type maniptype;
869 
870 	if (!(ct_action & TCA_CT_ACT_NAT))
871 		return NF_ACCEPT;
872 
873 	/* Add NAT extension if not confirmed yet. */
874 	if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
875 		return NF_DROP;   /* Can't NAT. */
876 
877 	if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) &&
878 	    (ctinfo != IP_CT_RELATED || commit)) {
879 		/* NAT an established or related connection like before. */
880 		if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
881 			/* This is the REPLY direction for a connection
882 			 * for which NAT was applied in the forward
883 			 * direction.  Do the reverse NAT.
884 			 */
885 			maniptype = ct->status & IPS_SRC_NAT
886 				? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
887 		else
888 			maniptype = ct->status & IPS_SRC_NAT
889 				? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
890 	} else if (ct_action & TCA_CT_ACT_NAT_SRC) {
891 		maniptype = NF_NAT_MANIP_SRC;
892 	} else if (ct_action & TCA_CT_ACT_NAT_DST) {
893 		maniptype = NF_NAT_MANIP_DST;
894 	} else {
895 		return NF_ACCEPT;
896 	}
897 
898 	err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
899 	if (err == NF_ACCEPT &&
900 	    ct->status & IPS_SRC_NAT && ct->status & IPS_DST_NAT) {
901 		if (maniptype == NF_NAT_MANIP_SRC)
902 			maniptype = NF_NAT_MANIP_DST;
903 		else
904 			maniptype = NF_NAT_MANIP_SRC;
905 
906 		err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
907 	}
908 	return err;
909 #else
910 	return NF_ACCEPT;
911 #endif
912 }
913 
914 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
915 		      struct tcf_result *res)
916 {
917 	struct net *net = dev_net(skb->dev);
918 	bool cached, commit, clear, force;
919 	enum ip_conntrack_info ctinfo;
920 	struct tcf_ct *c = to_ct(a);
921 	struct nf_conn *tmpl = NULL;
922 	struct nf_hook_state state;
923 	int nh_ofs, err, retval;
924 	struct tcf_ct_params *p;
925 	bool skip_add = false;
926 	bool defrag = false;
927 	struct nf_conn *ct;
928 	u8 family;
929 
930 	p = rcu_dereference_bh(c->params);
931 
932 	retval = READ_ONCE(c->tcf_action);
933 	commit = p->ct_action & TCA_CT_ACT_COMMIT;
934 	clear = p->ct_action & TCA_CT_ACT_CLEAR;
935 	force = p->ct_action & TCA_CT_ACT_FORCE;
936 	tmpl = p->tmpl;
937 
938 	tcf_lastuse_update(&c->tcf_tm);
939 
940 	if (clear) {
941 		ct = nf_ct_get(skb, &ctinfo);
942 		if (ct) {
943 			nf_conntrack_put(&ct->ct_general);
944 			nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
945 		}
946 
947 		goto out;
948 	}
949 
950 	family = tcf_ct_skb_nf_family(skb);
951 	if (family == NFPROTO_UNSPEC)
952 		goto drop;
953 
954 	/* The conntrack module expects to be working at L3.
955 	 * We also try to pull the IPv4/6 header to linear area
956 	 */
957 	nh_ofs = skb_network_offset(skb);
958 	skb_pull_rcsum(skb, nh_ofs);
959 	err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
960 	if (err == -EINPROGRESS) {
961 		retval = TC_ACT_STOLEN;
962 		goto out;
963 	}
964 	if (err)
965 		goto drop;
966 
967 	err = tcf_ct_skb_network_trim(skb, family);
968 	if (err)
969 		goto drop;
970 
971 	/* If we are recirculating packets to match on ct fields and
972 	 * committing with a separate ct action, then we don't need to
973 	 * actually run the packet through conntrack twice unless it's for a
974 	 * different zone.
975 	 */
976 	cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);
977 	if (!cached) {
978 		if (!commit && tcf_ct_flow_table_lookup(p, skb, family)) {
979 			skip_add = true;
980 			goto do_nat;
981 		}
982 
983 		/* Associate skb with specified zone. */
984 		if (tmpl) {
985 			ct = nf_ct_get(skb, &ctinfo);
986 			if (skb_nfct(skb))
987 				nf_conntrack_put(skb_nfct(skb));
988 			nf_conntrack_get(&tmpl->ct_general);
989 			nf_ct_set(skb, tmpl, IP_CT_NEW);
990 		}
991 
992 		state.hook = NF_INET_PRE_ROUTING;
993 		state.net = net;
994 		state.pf = family;
995 		err = nf_conntrack_in(skb, &state);
996 		if (err != NF_ACCEPT)
997 			goto out_push;
998 	}
999 
1000 do_nat:
1001 	ct = nf_ct_get(skb, &ctinfo);
1002 	if (!ct)
1003 		goto out_push;
1004 	nf_ct_deliver_cached_events(ct);
1005 
1006 	err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1007 	if (err != NF_ACCEPT)
1008 		goto drop;
1009 
1010 	if (commit) {
1011 		tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1012 		tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1013 
1014 		/* This will take care of sending queued events
1015 		 * even if the connection is already confirmed.
1016 		 */
1017 		nf_conntrack_confirm(skb);
1018 	} else if (!skip_add) {
1019 		tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1020 	}
1021 
1022 out_push:
1023 	skb_push_rcsum(skb, nh_ofs);
1024 
1025 out:
1026 	tcf_action_update_bstats(&c->common, skb);
1027 	if (defrag)
1028 		qdisc_skb_cb(skb)->pkt_len = skb->len;
1029 	return retval;
1030 
1031 drop:
1032 	tcf_action_inc_drop_qstats(&c->common);
1033 	return TC_ACT_SHOT;
1034 }
1035 
1036 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1037 	[TCA_CT_ACTION] = { .type = NLA_U16 },
1038 	[TCA_CT_PARMS] = { .type = NLA_EXACT_LEN, .len = sizeof(struct tc_ct) },
1039 	[TCA_CT_ZONE] = { .type = NLA_U16 },
1040 	[TCA_CT_MARK] = { .type = NLA_U32 },
1041 	[TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1042 	[TCA_CT_LABELS] = { .type = NLA_BINARY,
1043 			    .len = 128 / BITS_PER_BYTE },
1044 	[TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1045 				 .len = 128 / BITS_PER_BYTE },
1046 	[TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1047 	[TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1048 	[TCA_CT_NAT_IPV6_MIN] = { .type = NLA_EXACT_LEN,
1049 				  .len = sizeof(struct in6_addr) },
1050 	[TCA_CT_NAT_IPV6_MAX] = { .type = NLA_EXACT_LEN,
1051 				   .len = sizeof(struct in6_addr) },
1052 	[TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1053 	[TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1054 };
1055 
1056 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1057 				  struct tc_ct *parm,
1058 				  struct nlattr **tb,
1059 				  struct netlink_ext_ack *extack)
1060 {
1061 	struct nf_nat_range2 *range;
1062 
1063 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1064 		return 0;
1065 
1066 	if (!IS_ENABLED(CONFIG_NF_NAT)) {
1067 		NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1068 		return -EOPNOTSUPP;
1069 	}
1070 
1071 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1072 		return 0;
1073 
1074 	if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1075 	    (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1076 		NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1077 		return -EOPNOTSUPP;
1078 	}
1079 
1080 	range = &p->range;
1081 	if (tb[TCA_CT_NAT_IPV4_MIN]) {
1082 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1083 
1084 		p->ipv4_range = true;
1085 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1086 		range->min_addr.ip =
1087 			nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1088 
1089 		range->max_addr.ip = max_attr ?
1090 				     nla_get_in_addr(max_attr) :
1091 				     range->min_addr.ip;
1092 	} else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1093 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1094 
1095 		p->ipv4_range = false;
1096 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1097 		range->min_addr.in6 =
1098 			nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1099 
1100 		range->max_addr.in6 = max_attr ?
1101 				      nla_get_in6_addr(max_attr) :
1102 				      range->min_addr.in6;
1103 	}
1104 
1105 	if (tb[TCA_CT_NAT_PORT_MIN]) {
1106 		range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1107 		range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1108 
1109 		range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1110 				       nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1111 				       range->min_proto.all;
1112 	}
1113 
1114 	return 0;
1115 }
1116 
1117 static void tcf_ct_set_key_val(struct nlattr **tb,
1118 			       void *val, int val_type,
1119 			       void *mask, int mask_type,
1120 			       int len)
1121 {
1122 	if (!tb[val_type])
1123 		return;
1124 	nla_memcpy(val, tb[val_type], len);
1125 
1126 	if (!mask)
1127 		return;
1128 
1129 	if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1130 		memset(mask, 0xff, len);
1131 	else
1132 		nla_memcpy(mask, tb[mask_type], len);
1133 }
1134 
1135 static int tcf_ct_fill_params(struct net *net,
1136 			      struct tcf_ct_params *p,
1137 			      struct tc_ct *parm,
1138 			      struct nlattr **tb,
1139 			      struct netlink_ext_ack *extack)
1140 {
1141 	struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1142 	struct nf_conntrack_zone zone;
1143 	struct nf_conn *tmpl;
1144 	int err;
1145 
1146 	p->zone = NF_CT_DEFAULT_ZONE_ID;
1147 
1148 	tcf_ct_set_key_val(tb,
1149 			   &p->ct_action, TCA_CT_ACTION,
1150 			   NULL, TCA_CT_UNSPEC,
1151 			   sizeof(p->ct_action));
1152 
1153 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1154 		return 0;
1155 
1156 	err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1157 	if (err)
1158 		return err;
1159 
1160 	if (tb[TCA_CT_MARK]) {
1161 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1162 			NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1163 			return -EOPNOTSUPP;
1164 		}
1165 		tcf_ct_set_key_val(tb,
1166 				   &p->mark, TCA_CT_MARK,
1167 				   &p->mark_mask, TCA_CT_MARK_MASK,
1168 				   sizeof(p->mark));
1169 	}
1170 
1171 	if (tb[TCA_CT_LABELS]) {
1172 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1173 			NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1174 			return -EOPNOTSUPP;
1175 		}
1176 
1177 		if (!tn->labels) {
1178 			NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1179 			return -EOPNOTSUPP;
1180 		}
1181 		tcf_ct_set_key_val(tb,
1182 				   p->labels, TCA_CT_LABELS,
1183 				   p->labels_mask, TCA_CT_LABELS_MASK,
1184 				   sizeof(p->labels));
1185 	}
1186 
1187 	if (tb[TCA_CT_ZONE]) {
1188 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1189 			NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1190 			return -EOPNOTSUPP;
1191 		}
1192 
1193 		tcf_ct_set_key_val(tb,
1194 				   &p->zone, TCA_CT_ZONE,
1195 				   NULL, TCA_CT_UNSPEC,
1196 				   sizeof(p->zone));
1197 	}
1198 
1199 	if (p->zone == NF_CT_DEFAULT_ZONE_ID)
1200 		return 0;
1201 
1202 	nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1203 	tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1204 	if (!tmpl) {
1205 		NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1206 		return -ENOMEM;
1207 	}
1208 	__set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1209 	nf_conntrack_get(&tmpl->ct_general);
1210 	p->tmpl = tmpl;
1211 
1212 	return 0;
1213 }
1214 
1215 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1216 		       struct nlattr *est, struct tc_action **a,
1217 		       int replace, int bind, bool rtnl_held,
1218 		       struct tcf_proto *tp, u32 flags,
1219 		       struct netlink_ext_ack *extack)
1220 {
1221 	struct tc_action_net *tn = net_generic(net, ct_net_id);
1222 	struct tcf_ct_params *params = NULL;
1223 	struct nlattr *tb[TCA_CT_MAX + 1];
1224 	struct tcf_chain *goto_ch = NULL;
1225 	struct tc_ct *parm;
1226 	struct tcf_ct *c;
1227 	int err, res = 0;
1228 	u32 index;
1229 
1230 	if (!nla) {
1231 		NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1232 		return -EINVAL;
1233 	}
1234 
1235 	err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1236 	if (err < 0)
1237 		return err;
1238 
1239 	if (!tb[TCA_CT_PARMS]) {
1240 		NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1241 		return -EINVAL;
1242 	}
1243 	parm = nla_data(tb[TCA_CT_PARMS]);
1244 	index = parm->index;
1245 	err = tcf_idr_check_alloc(tn, &index, a, bind);
1246 	if (err < 0)
1247 		return err;
1248 
1249 	if (!err) {
1250 		err = tcf_idr_create_from_flags(tn, index, est, a,
1251 						&act_ct_ops, bind, flags);
1252 		if (err) {
1253 			tcf_idr_cleanup(tn, index);
1254 			return err;
1255 		}
1256 		res = ACT_P_CREATED;
1257 	} else {
1258 		if (bind)
1259 			return 0;
1260 
1261 		if (!replace) {
1262 			tcf_idr_release(*a, bind);
1263 			return -EEXIST;
1264 		}
1265 	}
1266 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1267 	if (err < 0)
1268 		goto cleanup;
1269 
1270 	c = to_ct(*a);
1271 
1272 	params = kzalloc(sizeof(*params), GFP_KERNEL);
1273 	if (unlikely(!params)) {
1274 		err = -ENOMEM;
1275 		goto cleanup;
1276 	}
1277 
1278 	err = tcf_ct_fill_params(net, params, parm, tb, extack);
1279 	if (err)
1280 		goto cleanup;
1281 
1282 	err = tcf_ct_flow_table_get(params);
1283 	if (err)
1284 		goto cleanup;
1285 
1286 	spin_lock_bh(&c->tcf_lock);
1287 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1288 	params = rcu_replace_pointer(c->params, params,
1289 				     lockdep_is_held(&c->tcf_lock));
1290 	spin_unlock_bh(&c->tcf_lock);
1291 
1292 	if (goto_ch)
1293 		tcf_chain_put_by_act(goto_ch);
1294 	if (params)
1295 		call_rcu(&params->rcu, tcf_ct_params_free);
1296 	if (res == ACT_P_CREATED)
1297 		tcf_idr_insert(tn, *a);
1298 
1299 	return res;
1300 
1301 cleanup:
1302 	if (goto_ch)
1303 		tcf_chain_put_by_act(goto_ch);
1304 	kfree(params);
1305 	tcf_idr_release(*a, bind);
1306 	return err;
1307 }
1308 
1309 static void tcf_ct_cleanup(struct tc_action *a)
1310 {
1311 	struct tcf_ct_params *params;
1312 	struct tcf_ct *c = to_ct(a);
1313 
1314 	params = rcu_dereference_protected(c->params, 1);
1315 	if (params)
1316 		call_rcu(&params->rcu, tcf_ct_params_free);
1317 }
1318 
1319 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1320 			       void *val, int val_type,
1321 			       void *mask, int mask_type,
1322 			       int len)
1323 {
1324 	int err;
1325 
1326 	if (mask && !memchr_inv(mask, 0, len))
1327 		return 0;
1328 
1329 	err = nla_put(skb, val_type, len, val);
1330 	if (err)
1331 		return err;
1332 
1333 	if (mask_type != TCA_CT_UNSPEC) {
1334 		err = nla_put(skb, mask_type, len, mask);
1335 		if (err)
1336 			return err;
1337 	}
1338 
1339 	return 0;
1340 }
1341 
1342 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1343 {
1344 	struct nf_nat_range2 *range = &p->range;
1345 
1346 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1347 		return 0;
1348 
1349 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1350 		return 0;
1351 
1352 	if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1353 		if (p->ipv4_range) {
1354 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1355 					    range->min_addr.ip))
1356 				return -1;
1357 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1358 					    range->max_addr.ip))
1359 				return -1;
1360 		} else {
1361 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1362 					     &range->min_addr.in6))
1363 				return -1;
1364 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1365 					     &range->max_addr.in6))
1366 				return -1;
1367 		}
1368 	}
1369 
1370 	if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1371 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1372 				 range->min_proto.all))
1373 			return -1;
1374 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1375 				 range->max_proto.all))
1376 			return -1;
1377 	}
1378 
1379 	return 0;
1380 }
1381 
1382 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1383 			      int bind, int ref)
1384 {
1385 	unsigned char *b = skb_tail_pointer(skb);
1386 	struct tcf_ct *c = to_ct(a);
1387 	struct tcf_ct_params *p;
1388 
1389 	struct tc_ct opt = {
1390 		.index   = c->tcf_index,
1391 		.refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1392 		.bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1393 	};
1394 	struct tcf_t t;
1395 
1396 	spin_lock_bh(&c->tcf_lock);
1397 	p = rcu_dereference_protected(c->params,
1398 				      lockdep_is_held(&c->tcf_lock));
1399 	opt.action = c->tcf_action;
1400 
1401 	if (tcf_ct_dump_key_val(skb,
1402 				&p->ct_action, TCA_CT_ACTION,
1403 				NULL, TCA_CT_UNSPEC,
1404 				sizeof(p->ct_action)))
1405 		goto nla_put_failure;
1406 
1407 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1408 		goto skip_dump;
1409 
1410 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1411 	    tcf_ct_dump_key_val(skb,
1412 				&p->mark, TCA_CT_MARK,
1413 				&p->mark_mask, TCA_CT_MARK_MASK,
1414 				sizeof(p->mark)))
1415 		goto nla_put_failure;
1416 
1417 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1418 	    tcf_ct_dump_key_val(skb,
1419 				p->labels, TCA_CT_LABELS,
1420 				p->labels_mask, TCA_CT_LABELS_MASK,
1421 				sizeof(p->labels)))
1422 		goto nla_put_failure;
1423 
1424 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1425 	    tcf_ct_dump_key_val(skb,
1426 				&p->zone, TCA_CT_ZONE,
1427 				NULL, TCA_CT_UNSPEC,
1428 				sizeof(p->zone)))
1429 		goto nla_put_failure;
1430 
1431 	if (tcf_ct_dump_nat(skb, p))
1432 		goto nla_put_failure;
1433 
1434 skip_dump:
1435 	if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1436 		goto nla_put_failure;
1437 
1438 	tcf_tm_dump(&t, &c->tcf_tm);
1439 	if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1440 		goto nla_put_failure;
1441 	spin_unlock_bh(&c->tcf_lock);
1442 
1443 	return skb->len;
1444 nla_put_failure:
1445 	spin_unlock_bh(&c->tcf_lock);
1446 	nlmsg_trim(skb, b);
1447 	return -1;
1448 }
1449 
1450 static int tcf_ct_walker(struct net *net, struct sk_buff *skb,
1451 			 struct netlink_callback *cb, int type,
1452 			 const struct tc_action_ops *ops,
1453 			 struct netlink_ext_ack *extack)
1454 {
1455 	struct tc_action_net *tn = net_generic(net, ct_net_id);
1456 
1457 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
1458 }
1459 
1460 static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index)
1461 {
1462 	struct tc_action_net *tn = net_generic(net, ct_net_id);
1463 
1464 	return tcf_idr_search(tn, a, index);
1465 }
1466 
1467 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1468 			     u64 drops, u64 lastuse, bool hw)
1469 {
1470 	struct tcf_ct *c = to_ct(a);
1471 
1472 	tcf_action_update_stats(a, bytes, packets, drops, hw);
1473 	c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1474 }
1475 
1476 static struct tc_action_ops act_ct_ops = {
1477 	.kind		=	"ct",
1478 	.id		=	TCA_ID_CT,
1479 	.owner		=	THIS_MODULE,
1480 	.act		=	tcf_ct_act,
1481 	.dump		=	tcf_ct_dump,
1482 	.init		=	tcf_ct_init,
1483 	.cleanup	=	tcf_ct_cleanup,
1484 	.walk		=	tcf_ct_walker,
1485 	.lookup		=	tcf_ct_search,
1486 	.stats_update	=	tcf_stats_update,
1487 	.size		=	sizeof(struct tcf_ct),
1488 };
1489 
1490 static __net_init int ct_init_net(struct net *net)
1491 {
1492 	unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1493 	struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1494 
1495 	if (nf_connlabels_get(net, n_bits - 1)) {
1496 		tn->labels = false;
1497 		pr_err("act_ct: Failed to set connlabels length");
1498 	} else {
1499 		tn->labels = true;
1500 	}
1501 
1502 	return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1503 }
1504 
1505 static void __net_exit ct_exit_net(struct list_head *net_list)
1506 {
1507 	struct net *net;
1508 
1509 	rtnl_lock();
1510 	list_for_each_entry(net, net_list, exit_list) {
1511 		struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1512 
1513 		if (tn->labels)
1514 			nf_connlabels_put(net);
1515 	}
1516 	rtnl_unlock();
1517 
1518 	tc_action_net_exit(net_list, ct_net_id);
1519 }
1520 
1521 static struct pernet_operations ct_net_ops = {
1522 	.init = ct_init_net,
1523 	.exit_batch = ct_exit_net,
1524 	.id   = &ct_net_id,
1525 	.size = sizeof(struct tc_ct_action_net),
1526 };
1527 
1528 static int __init ct_init_module(void)
1529 {
1530 	int err;
1531 
1532 	act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1533 	if (!act_ct_wq)
1534 		return -ENOMEM;
1535 
1536 	err = tcf_ct_flow_tables_init();
1537 	if (err)
1538 		goto err_tbl_init;
1539 
1540 	err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1541 	if (err)
1542 		goto err_register;
1543 
1544 	return 0;
1545 
1546 err_tbl_init:
1547 	destroy_workqueue(act_ct_wq);
1548 err_register:
1549 	tcf_ct_flow_tables_uninit();
1550 	return err;
1551 }
1552 
1553 static void __exit ct_cleanup_module(void)
1554 {
1555 	tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1556 	tcf_ct_flow_tables_uninit();
1557 	destroy_workqueue(act_ct_wq);
1558 }
1559 
1560 module_init(ct_init_module);
1561 module_exit(ct_cleanup_module);
1562 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1563 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1564 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1565 MODULE_DESCRIPTION("Connection tracking action");
1566 MODULE_LICENSE("GPL v2");
1567