xref: /linux/net/sched/act_ct.c (revision d9afbb3509900a953f5cf90bc57e793ee80c1108)
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/ipv6/nf_defrag_ipv6.h>
34 #include <uapi/linux/netfilter/nf_nat.h>
35 
36 static struct workqueue_struct *act_ct_wq;
37 static struct rhashtable zones_ht;
38 static DEFINE_MUTEX(zones_mutex);
39 
40 struct tcf_ct_flow_table {
41 	struct rhash_head node; /* In zones tables */
42 
43 	struct rcu_work rwork;
44 	struct nf_flowtable nf_ft;
45 	refcount_t ref;
46 	u16 zone;
47 
48 	bool dying;
49 };
50 
51 static const struct rhashtable_params zones_params = {
52 	.head_offset = offsetof(struct tcf_ct_flow_table, node),
53 	.key_offset = offsetof(struct tcf_ct_flow_table, zone),
54 	.key_len = sizeof_field(struct tcf_ct_flow_table, zone),
55 	.automatic_shrinking = true,
56 };
57 
58 static struct flow_action_entry *
59 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action)
60 {
61 	int i = flow_action->num_entries++;
62 
63 	return &flow_action->entries[i];
64 }
65 
66 static void tcf_ct_add_mangle_action(struct flow_action *action,
67 				     enum flow_action_mangle_base htype,
68 				     u32 offset,
69 				     u32 mask,
70 				     u32 val)
71 {
72 	struct flow_action_entry *entry;
73 
74 	entry = tcf_ct_flow_table_flow_action_get_next(action);
75 	entry->id = FLOW_ACTION_MANGLE;
76 	entry->mangle.htype = htype;
77 	entry->mangle.mask = ~mask;
78 	entry->mangle.offset = offset;
79 	entry->mangle.val = val;
80 }
81 
82 /* The following nat helper functions check if the inverted reverse tuple
83  * (target) is different then the current dir tuple - meaning nat for ports
84  * and/or ip is needed, and add the relevant mangle actions.
85  */
86 static void
87 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple,
88 				      struct nf_conntrack_tuple target,
89 				      struct flow_action *action)
90 {
91 	if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
92 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
93 					 offsetof(struct iphdr, saddr),
94 					 0xFFFFFFFF,
95 					 be32_to_cpu(target.src.u3.ip));
96 	if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
97 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
98 					 offsetof(struct iphdr, daddr),
99 					 0xFFFFFFFF,
100 					 be32_to_cpu(target.dst.u3.ip));
101 }
102 
103 static void
104 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action,
105 				   union nf_inet_addr *addr,
106 				   u32 offset)
107 {
108 	int i;
109 
110 	for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++)
111 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
112 					 i * sizeof(u32) + offset,
113 					 0xFFFFFFFF, be32_to_cpu(addr->ip6[i]));
114 }
115 
116 static void
117 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple,
118 				      struct nf_conntrack_tuple target,
119 				      struct flow_action *action)
120 {
121 	if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
122 		tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3,
123 						   offsetof(struct ipv6hdr,
124 							    saddr));
125 	if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
126 		tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3,
127 						   offsetof(struct ipv6hdr,
128 							    daddr));
129 }
130 
131 static void
132 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple,
133 				     struct nf_conntrack_tuple target,
134 				     struct flow_action *action)
135 {
136 	__be16 target_src = target.src.u.tcp.port;
137 	__be16 target_dst = target.dst.u.tcp.port;
138 
139 	if (target_src != tuple->src.u.tcp.port)
140 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
141 					 offsetof(struct tcphdr, source),
142 					 0xFFFF, be16_to_cpu(target_src));
143 	if (target_dst != tuple->dst.u.tcp.port)
144 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
145 					 offsetof(struct tcphdr, dest),
146 					 0xFFFF, be16_to_cpu(target_dst));
147 }
148 
149 static void
150 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple,
151 				     struct nf_conntrack_tuple target,
152 				     struct flow_action *action)
153 {
154 	__be16 target_src = target.src.u.udp.port;
155 	__be16 target_dst = target.dst.u.udp.port;
156 
157 	if (target_src != tuple->src.u.udp.port)
158 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
159 					 offsetof(struct udphdr, source),
160 					 0xFFFF, be16_to_cpu(target_src));
161 	if (target_dst != tuple->dst.u.udp.port)
162 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
163 					 offsetof(struct udphdr, dest),
164 					 0xFFFF, be16_to_cpu(target_dst));
165 }
166 
167 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct,
168 					      enum ip_conntrack_dir dir,
169 					      struct flow_action *action)
170 {
171 	struct nf_conn_labels *ct_labels;
172 	struct flow_action_entry *entry;
173 	enum ip_conntrack_info ctinfo;
174 	u32 *act_ct_labels;
175 
176 	entry = tcf_ct_flow_table_flow_action_get_next(action);
177 	entry->id = FLOW_ACTION_CT_METADATA;
178 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
179 	entry->ct_metadata.mark = ct->mark;
180 #endif
181 	ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
182 					     IP_CT_ESTABLISHED_REPLY;
183 	/* aligns with the CT reference on the SKB nf_ct_set */
184 	entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
185 
186 	act_ct_labels = entry->ct_metadata.labels;
187 	ct_labels = nf_ct_labels_find(ct);
188 	if (ct_labels)
189 		memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
190 	else
191 		memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
192 }
193 
194 static int tcf_ct_flow_table_add_action_nat(struct net *net,
195 					    struct nf_conn *ct,
196 					    enum ip_conntrack_dir dir,
197 					    struct flow_action *action)
198 {
199 	const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
200 	struct nf_conntrack_tuple target;
201 
202 	if (!(ct->status & IPS_NAT_MASK))
203 		return 0;
204 
205 	nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
206 
207 	switch (tuple->src.l3num) {
208 	case NFPROTO_IPV4:
209 		tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
210 						      action);
211 		break;
212 	case NFPROTO_IPV6:
213 		tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
214 						      action);
215 		break;
216 	default:
217 		return -EOPNOTSUPP;
218 	}
219 
220 	switch (nf_ct_protonum(ct)) {
221 	case IPPROTO_TCP:
222 		tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
223 		break;
224 	case IPPROTO_UDP:
225 		tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
226 		break;
227 	default:
228 		return -EOPNOTSUPP;
229 	}
230 
231 	return 0;
232 }
233 
234 static int tcf_ct_flow_table_fill_actions(struct net *net,
235 					  const struct flow_offload *flow,
236 					  enum flow_offload_tuple_dir tdir,
237 					  struct nf_flow_rule *flow_rule)
238 {
239 	struct flow_action *action = &flow_rule->rule->action;
240 	int num_entries = action->num_entries;
241 	struct nf_conn *ct = flow->ct;
242 	enum ip_conntrack_dir dir;
243 	int i, err;
244 
245 	switch (tdir) {
246 	case FLOW_OFFLOAD_DIR_ORIGINAL:
247 		dir = IP_CT_DIR_ORIGINAL;
248 		break;
249 	case FLOW_OFFLOAD_DIR_REPLY:
250 		dir = IP_CT_DIR_REPLY;
251 		break;
252 	default:
253 		return -EOPNOTSUPP;
254 	}
255 
256 	err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
257 	if (err)
258 		goto err_nat;
259 
260 	tcf_ct_flow_table_add_action_meta(ct, dir, action);
261 	return 0;
262 
263 err_nat:
264 	/* Clear filled actions */
265 	for (i = num_entries; i < action->num_entries; i++)
266 		memset(&action->entries[i], 0, sizeof(action->entries[i]));
267 	action->num_entries = num_entries;
268 
269 	return err;
270 }
271 
272 static struct nf_flowtable_type flowtable_ct = {
273 	.action		= tcf_ct_flow_table_fill_actions,
274 	.owner		= THIS_MODULE,
275 };
276 
277 static int tcf_ct_flow_table_get(struct tcf_ct_params *params)
278 {
279 	struct tcf_ct_flow_table *ct_ft;
280 	int err = -ENOMEM;
281 
282 	mutex_lock(&zones_mutex);
283 	ct_ft = rhashtable_lookup_fast(&zones_ht, &params->zone, zones_params);
284 	if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
285 		goto out_unlock;
286 
287 	ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
288 	if (!ct_ft)
289 		goto err_alloc;
290 	refcount_set(&ct_ft->ref, 1);
291 
292 	ct_ft->zone = params->zone;
293 	err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
294 	if (err)
295 		goto err_insert;
296 
297 	ct_ft->nf_ft.type = &flowtable_ct;
298 	ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD;
299 	err = nf_flow_table_init(&ct_ft->nf_ft);
300 	if (err)
301 		goto err_init;
302 
303 	__module_get(THIS_MODULE);
304 out_unlock:
305 	params->ct_ft = ct_ft;
306 	params->nf_ft = &ct_ft->nf_ft;
307 	mutex_unlock(&zones_mutex);
308 
309 	return 0;
310 
311 err_init:
312 	rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
313 err_insert:
314 	kfree(ct_ft);
315 err_alloc:
316 	mutex_unlock(&zones_mutex);
317 	return err;
318 }
319 
320 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
321 {
322 	struct tcf_ct_flow_table *ct_ft;
323 
324 	ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
325 			     rwork);
326 	nf_flow_table_free(&ct_ft->nf_ft);
327 	kfree(ct_ft);
328 
329 	module_put(THIS_MODULE);
330 }
331 
332 static void tcf_ct_flow_table_put(struct tcf_ct_params *params)
333 {
334 	struct tcf_ct_flow_table *ct_ft = params->ct_ft;
335 
336 	if (refcount_dec_and_test(&params->ct_ft->ref)) {
337 		rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
338 		INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
339 		queue_rcu_work(act_ct_wq, &ct_ft->rwork);
340 	}
341 }
342 
343 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
344 				  struct nf_conn *ct,
345 				  bool tcp)
346 {
347 	struct flow_offload *entry;
348 	int err;
349 
350 	if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
351 		return;
352 
353 	entry = flow_offload_alloc(ct);
354 	if (!entry) {
355 		WARN_ON_ONCE(1);
356 		goto err_alloc;
357 	}
358 
359 	if (tcp) {
360 		ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
361 		ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
362 	}
363 
364 	err = flow_offload_add(&ct_ft->nf_ft, entry);
365 	if (err)
366 		goto err_add;
367 
368 	return;
369 
370 err_add:
371 	flow_offload_free(entry);
372 err_alloc:
373 	clear_bit(IPS_OFFLOAD_BIT, &ct->status);
374 }
375 
376 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
377 					   struct nf_conn *ct,
378 					   enum ip_conntrack_info ctinfo)
379 {
380 	bool tcp = false;
381 
382 	if (ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY)
383 		return;
384 
385 	switch (nf_ct_protonum(ct)) {
386 	case IPPROTO_TCP:
387 		tcp = true;
388 		if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
389 			return;
390 		break;
391 	case IPPROTO_UDP:
392 		break;
393 	default:
394 		return;
395 	}
396 
397 	if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
398 	    ct->status & IPS_SEQ_ADJUST)
399 		return;
400 
401 	tcf_ct_flow_table_add(ct_ft, ct, tcp);
402 }
403 
404 static bool
405 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
406 				  struct flow_offload_tuple *tuple,
407 				  struct tcphdr **tcph)
408 {
409 	struct flow_ports *ports;
410 	unsigned int thoff;
411 	struct iphdr *iph;
412 
413 	if (!pskb_network_may_pull(skb, sizeof(*iph)))
414 		return false;
415 
416 	iph = ip_hdr(skb);
417 	thoff = iph->ihl * 4;
418 
419 	if (ip_is_fragment(iph) ||
420 	    unlikely(thoff != sizeof(struct iphdr)))
421 		return false;
422 
423 	if (iph->protocol != IPPROTO_TCP &&
424 	    iph->protocol != IPPROTO_UDP)
425 		return false;
426 
427 	if (iph->ttl <= 1)
428 		return false;
429 
430 	if (!pskb_network_may_pull(skb, iph->protocol == IPPROTO_TCP ?
431 					thoff + sizeof(struct tcphdr) :
432 					thoff + sizeof(*ports)))
433 		return false;
434 
435 	iph = ip_hdr(skb);
436 	if (iph->protocol == IPPROTO_TCP)
437 		*tcph = (void *)(skb_network_header(skb) + thoff);
438 
439 	ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
440 	tuple->src_v4.s_addr = iph->saddr;
441 	tuple->dst_v4.s_addr = iph->daddr;
442 	tuple->src_port = ports->source;
443 	tuple->dst_port = ports->dest;
444 	tuple->l3proto = AF_INET;
445 	tuple->l4proto = iph->protocol;
446 
447 	return true;
448 }
449 
450 static bool
451 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
452 				  struct flow_offload_tuple *tuple,
453 				  struct tcphdr **tcph)
454 {
455 	struct flow_ports *ports;
456 	struct ipv6hdr *ip6h;
457 	unsigned int thoff;
458 
459 	if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
460 		return false;
461 
462 	ip6h = ipv6_hdr(skb);
463 
464 	if (ip6h->nexthdr != IPPROTO_TCP &&
465 	    ip6h->nexthdr != IPPROTO_UDP)
466 		return false;
467 
468 	if (ip6h->hop_limit <= 1)
469 		return false;
470 
471 	thoff = sizeof(*ip6h);
472 	if (!pskb_network_may_pull(skb, ip6h->nexthdr == IPPROTO_TCP ?
473 					thoff + sizeof(struct tcphdr) :
474 					thoff + sizeof(*ports)))
475 		return false;
476 
477 	ip6h = ipv6_hdr(skb);
478 	if (ip6h->nexthdr == IPPROTO_TCP)
479 		*tcph = (void *)(skb_network_header(skb) + thoff);
480 
481 	ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
482 	tuple->src_v6 = ip6h->saddr;
483 	tuple->dst_v6 = ip6h->daddr;
484 	tuple->src_port = ports->source;
485 	tuple->dst_port = ports->dest;
486 	tuple->l3proto = AF_INET6;
487 	tuple->l4proto = ip6h->nexthdr;
488 
489 	return true;
490 }
491 
492 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
493 				     struct sk_buff *skb,
494 				     u8 family)
495 {
496 	struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
497 	struct flow_offload_tuple_rhash *tuplehash;
498 	struct flow_offload_tuple tuple = {};
499 	enum ip_conntrack_info ctinfo;
500 	struct tcphdr *tcph = NULL;
501 	struct flow_offload *flow;
502 	struct nf_conn *ct;
503 	u8 dir;
504 
505 	/* Previously seen or loopback */
506 	ct = nf_ct_get(skb, &ctinfo);
507 	if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
508 		return false;
509 
510 	switch (family) {
511 	case NFPROTO_IPV4:
512 		if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
513 			return false;
514 		break;
515 	case NFPROTO_IPV6:
516 		if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
517 			return false;
518 		break;
519 	default:
520 		return false;
521 	}
522 
523 	tuplehash = flow_offload_lookup(nf_ft, &tuple);
524 	if (!tuplehash)
525 		return false;
526 
527 	dir = tuplehash->tuple.dir;
528 	flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
529 	ct = flow->ct;
530 
531 	if (tcph && (unlikely(tcph->fin || tcph->rst))) {
532 		flow_offload_teardown(flow);
533 		return false;
534 	}
535 
536 	ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
537 						    IP_CT_ESTABLISHED_REPLY;
538 
539 	flow_offload_refresh(nf_ft, flow);
540 	nf_conntrack_get(&ct->ct_general);
541 	nf_ct_set(skb, ct, ctinfo);
542 
543 	return true;
544 }
545 
546 static int tcf_ct_flow_tables_init(void)
547 {
548 	return rhashtable_init(&zones_ht, &zones_params);
549 }
550 
551 static void tcf_ct_flow_tables_uninit(void)
552 {
553 	rhashtable_destroy(&zones_ht);
554 }
555 
556 static struct tc_action_ops act_ct_ops;
557 static unsigned int ct_net_id;
558 
559 struct tc_ct_action_net {
560 	struct tc_action_net tn; /* Must be first */
561 	bool labels;
562 };
563 
564 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
565 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
566 				   u16 zone_id, bool force)
567 {
568 	enum ip_conntrack_info ctinfo;
569 	struct nf_conn *ct;
570 
571 	ct = nf_ct_get(skb, &ctinfo);
572 	if (!ct)
573 		return false;
574 	if (!net_eq(net, read_pnet(&ct->ct_net)))
575 		return false;
576 	if (nf_ct_zone(ct)->id != zone_id)
577 		return false;
578 
579 	/* Force conntrack entry direction. */
580 	if (force && CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
581 		if (nf_ct_is_confirmed(ct))
582 			nf_ct_kill(ct);
583 
584 		nf_conntrack_put(&ct->ct_general);
585 		nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
586 
587 		return false;
588 	}
589 
590 	return true;
591 }
592 
593 /* Trim the skb to the length specified by the IP/IPv6 header,
594  * removing any trailing lower-layer padding. This prepares the skb
595  * for higher-layer processing that assumes skb->len excludes padding
596  * (such as nf_ip_checksum). The caller needs to pull the skb to the
597  * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
598  */
599 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
600 {
601 	unsigned int len;
602 	int err;
603 
604 	switch (family) {
605 	case NFPROTO_IPV4:
606 		len = ntohs(ip_hdr(skb)->tot_len);
607 		break;
608 	case NFPROTO_IPV6:
609 		len = sizeof(struct ipv6hdr)
610 			+ ntohs(ipv6_hdr(skb)->payload_len);
611 		break;
612 	default:
613 		len = skb->len;
614 	}
615 
616 	err = pskb_trim_rcsum(skb, len);
617 
618 	return err;
619 }
620 
621 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
622 {
623 	u8 family = NFPROTO_UNSPEC;
624 
625 	switch (skb->protocol) {
626 	case htons(ETH_P_IP):
627 		family = NFPROTO_IPV4;
628 		break;
629 	case htons(ETH_P_IPV6):
630 		family = NFPROTO_IPV6;
631 		break;
632 	default:
633 		break;
634 	}
635 
636 	return family;
637 }
638 
639 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
640 {
641 	unsigned int len;
642 
643 	len =  skb_network_offset(skb) + sizeof(struct iphdr);
644 	if (unlikely(skb->len < len))
645 		return -EINVAL;
646 	if (unlikely(!pskb_may_pull(skb, len)))
647 		return -ENOMEM;
648 
649 	*frag = ip_is_fragment(ip_hdr(skb));
650 	return 0;
651 }
652 
653 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
654 {
655 	unsigned int flags = 0, len, payload_ofs = 0;
656 	unsigned short frag_off;
657 	int nexthdr;
658 
659 	len =  skb_network_offset(skb) + sizeof(struct ipv6hdr);
660 	if (unlikely(skb->len < len))
661 		return -EINVAL;
662 	if (unlikely(!pskb_may_pull(skb, len)))
663 		return -ENOMEM;
664 
665 	nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
666 	if (unlikely(nexthdr < 0))
667 		return -EPROTO;
668 
669 	*frag = flags & IP6_FH_F_FRAG;
670 	return 0;
671 }
672 
673 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
674 				   u8 family, u16 zone)
675 {
676 	enum ip_conntrack_info ctinfo;
677 	struct nf_conn *ct;
678 	int err = 0;
679 	bool frag;
680 
681 	/* Previously seen (loopback)? Ignore. */
682 	ct = nf_ct_get(skb, &ctinfo);
683 	if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
684 		return 0;
685 
686 	if (family == NFPROTO_IPV4)
687 		err = tcf_ct_ipv4_is_fragment(skb, &frag);
688 	else
689 		err = tcf_ct_ipv6_is_fragment(skb, &frag);
690 	if (err || !frag)
691 		return err;
692 
693 	skb_get(skb);
694 
695 	if (family == NFPROTO_IPV4) {
696 		enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
697 
698 		memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
699 		local_bh_disable();
700 		err = ip_defrag(net, skb, user);
701 		local_bh_enable();
702 		if (err && err != -EINPROGRESS)
703 			goto out_free;
704 	} else { /* NFPROTO_IPV6 */
705 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
706 		enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
707 
708 		memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
709 		err = nf_ct_frag6_gather(net, skb, user);
710 		if (err && err != -EINPROGRESS)
711 			goto out_free;
712 #else
713 		err = -EOPNOTSUPP;
714 		goto out_free;
715 #endif
716 	}
717 
718 	skb_clear_hash(skb);
719 	skb->ignore_df = 1;
720 	return err;
721 
722 out_free:
723 	kfree_skb(skb);
724 	return err;
725 }
726 
727 static void tcf_ct_params_free(struct rcu_head *head)
728 {
729 	struct tcf_ct_params *params = container_of(head,
730 						    struct tcf_ct_params, rcu);
731 
732 	tcf_ct_flow_table_put(params);
733 
734 	if (params->tmpl)
735 		nf_conntrack_put(&params->tmpl->ct_general);
736 	kfree(params);
737 }
738 
739 #if IS_ENABLED(CONFIG_NF_NAT)
740 /* Modelled after nf_nat_ipv[46]_fn().
741  * range is only used for new, uninitialized NAT state.
742  * Returns either NF_ACCEPT or NF_DROP.
743  */
744 static int ct_nat_execute(struct sk_buff *skb, struct nf_conn *ct,
745 			  enum ip_conntrack_info ctinfo,
746 			  const struct nf_nat_range2 *range,
747 			  enum nf_nat_manip_type maniptype)
748 {
749 	int hooknum, err = NF_ACCEPT;
750 
751 	/* See HOOK2MANIP(). */
752 	if (maniptype == NF_NAT_MANIP_SRC)
753 		hooknum = NF_INET_LOCAL_IN; /* Source NAT */
754 	else
755 		hooknum = NF_INET_LOCAL_OUT; /* Destination NAT */
756 
757 	switch (ctinfo) {
758 	case IP_CT_RELATED:
759 	case IP_CT_RELATED_REPLY:
760 		if (skb->protocol == htons(ETH_P_IP) &&
761 		    ip_hdr(skb)->protocol == IPPROTO_ICMP) {
762 			if (!nf_nat_icmp_reply_translation(skb, ct, ctinfo,
763 							   hooknum))
764 				err = NF_DROP;
765 			goto out;
766 		} else if (IS_ENABLED(CONFIG_IPV6) &&
767 			   skb->protocol == htons(ETH_P_IPV6)) {
768 			__be16 frag_off;
769 			u8 nexthdr = ipv6_hdr(skb)->nexthdr;
770 			int hdrlen = ipv6_skip_exthdr(skb,
771 						      sizeof(struct ipv6hdr),
772 						      &nexthdr, &frag_off);
773 
774 			if (hdrlen >= 0 && nexthdr == IPPROTO_ICMPV6) {
775 				if (!nf_nat_icmpv6_reply_translation(skb, ct,
776 								     ctinfo,
777 								     hooknum,
778 								     hdrlen))
779 					err = NF_DROP;
780 				goto out;
781 			}
782 		}
783 		/* Non-ICMP, fall thru to initialize if needed. */
784 		/* fall through */
785 	case IP_CT_NEW:
786 		/* Seen it before?  This can happen for loopback, retrans,
787 		 * or local packets.
788 		 */
789 		if (!nf_nat_initialized(ct, maniptype)) {
790 			/* Initialize according to the NAT action. */
791 			err = (range && range->flags & NF_NAT_RANGE_MAP_IPS)
792 				/* Action is set up to establish a new
793 				 * mapping.
794 				 */
795 				? nf_nat_setup_info(ct, range, maniptype)
796 				: nf_nat_alloc_null_binding(ct, hooknum);
797 			if (err != NF_ACCEPT)
798 				goto out;
799 		}
800 		break;
801 
802 	case IP_CT_ESTABLISHED:
803 	case IP_CT_ESTABLISHED_REPLY:
804 		break;
805 
806 	default:
807 		err = NF_DROP;
808 		goto out;
809 	}
810 
811 	err = nf_nat_packet(ct, ctinfo, hooknum, skb);
812 out:
813 	return err;
814 }
815 #endif /* CONFIG_NF_NAT */
816 
817 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
818 {
819 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
820 	u32 new_mark;
821 
822 	if (!mask)
823 		return;
824 
825 	new_mark = mark | (ct->mark & ~(mask));
826 	if (ct->mark != new_mark) {
827 		ct->mark = new_mark;
828 		if (nf_ct_is_confirmed(ct))
829 			nf_conntrack_event_cache(IPCT_MARK, ct);
830 	}
831 #endif
832 }
833 
834 static void tcf_ct_act_set_labels(struct nf_conn *ct,
835 				  u32 *labels,
836 				  u32 *labels_m)
837 {
838 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
839 	size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
840 
841 	if (!memchr_inv(labels_m, 0, labels_sz))
842 		return;
843 
844 	nf_connlabels_replace(ct, labels, labels_m, 4);
845 #endif
846 }
847 
848 static int tcf_ct_act_nat(struct sk_buff *skb,
849 			  struct nf_conn *ct,
850 			  enum ip_conntrack_info ctinfo,
851 			  int ct_action,
852 			  struct nf_nat_range2 *range,
853 			  bool commit)
854 {
855 #if IS_ENABLED(CONFIG_NF_NAT)
856 	int err;
857 	enum nf_nat_manip_type maniptype;
858 
859 	if (!(ct_action & TCA_CT_ACT_NAT))
860 		return NF_ACCEPT;
861 
862 	/* Add NAT extension if not confirmed yet. */
863 	if (!nf_ct_is_confirmed(ct) && !nf_ct_nat_ext_add(ct))
864 		return NF_DROP;   /* Can't NAT. */
865 
866 	if (ctinfo != IP_CT_NEW && (ct->status & IPS_NAT_MASK) &&
867 	    (ctinfo != IP_CT_RELATED || commit)) {
868 		/* NAT an established or related connection like before. */
869 		if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY)
870 			/* This is the REPLY direction for a connection
871 			 * for which NAT was applied in the forward
872 			 * direction.  Do the reverse NAT.
873 			 */
874 			maniptype = ct->status & IPS_SRC_NAT
875 				? NF_NAT_MANIP_DST : NF_NAT_MANIP_SRC;
876 		else
877 			maniptype = ct->status & IPS_SRC_NAT
878 				? NF_NAT_MANIP_SRC : NF_NAT_MANIP_DST;
879 	} else if (ct_action & TCA_CT_ACT_NAT_SRC) {
880 		maniptype = NF_NAT_MANIP_SRC;
881 	} else if (ct_action & TCA_CT_ACT_NAT_DST) {
882 		maniptype = NF_NAT_MANIP_DST;
883 	} else {
884 		return NF_ACCEPT;
885 	}
886 
887 	err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
888 	if (err == NF_ACCEPT &&
889 	    ct->status & IPS_SRC_NAT && ct->status & IPS_DST_NAT) {
890 		if (maniptype == NF_NAT_MANIP_SRC)
891 			maniptype = NF_NAT_MANIP_DST;
892 		else
893 			maniptype = NF_NAT_MANIP_SRC;
894 
895 		err = ct_nat_execute(skb, ct, ctinfo, range, maniptype);
896 	}
897 	return err;
898 #else
899 	return NF_ACCEPT;
900 #endif
901 }
902 
903 static int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
904 		      struct tcf_result *res)
905 {
906 	struct net *net = dev_net(skb->dev);
907 	bool cached, commit, clear, force;
908 	enum ip_conntrack_info ctinfo;
909 	struct tcf_ct *c = to_ct(a);
910 	struct nf_conn *tmpl = NULL;
911 	struct nf_hook_state state;
912 	int nh_ofs, err, retval;
913 	struct tcf_ct_params *p;
914 	bool skip_add = false;
915 	struct nf_conn *ct;
916 	u8 family;
917 
918 	p = rcu_dereference_bh(c->params);
919 
920 	retval = READ_ONCE(c->tcf_action);
921 	commit = p->ct_action & TCA_CT_ACT_COMMIT;
922 	clear = p->ct_action & TCA_CT_ACT_CLEAR;
923 	force = p->ct_action & TCA_CT_ACT_FORCE;
924 	tmpl = p->tmpl;
925 
926 	if (clear) {
927 		ct = nf_ct_get(skb, &ctinfo);
928 		if (ct) {
929 			nf_conntrack_put(&ct->ct_general);
930 			nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
931 		}
932 
933 		goto out;
934 	}
935 
936 	family = tcf_ct_skb_nf_family(skb);
937 	if (family == NFPROTO_UNSPEC)
938 		goto drop;
939 
940 	/* The conntrack module expects to be working at L3.
941 	 * We also try to pull the IPv4/6 header to linear area
942 	 */
943 	nh_ofs = skb_network_offset(skb);
944 	skb_pull_rcsum(skb, nh_ofs);
945 	err = tcf_ct_handle_fragments(net, skb, family, p->zone);
946 	if (err == -EINPROGRESS) {
947 		retval = TC_ACT_STOLEN;
948 		goto out;
949 	}
950 	if (err)
951 		goto drop;
952 
953 	err = tcf_ct_skb_network_trim(skb, family);
954 	if (err)
955 		goto drop;
956 
957 	/* If we are recirculating packets to match on ct fields and
958 	 * committing with a separate ct action, then we don't need to
959 	 * actually run the packet through conntrack twice unless it's for a
960 	 * different zone.
961 	 */
962 	cached = tcf_ct_skb_nfct_cached(net, skb, p->zone, force);
963 	if (!cached) {
964 		if (!commit && tcf_ct_flow_table_lookup(p, skb, family)) {
965 			skip_add = true;
966 			goto do_nat;
967 		}
968 
969 		/* Associate skb with specified zone. */
970 		if (tmpl) {
971 			ct = nf_ct_get(skb, &ctinfo);
972 			if (skb_nfct(skb))
973 				nf_conntrack_put(skb_nfct(skb));
974 			nf_conntrack_get(&tmpl->ct_general);
975 			nf_ct_set(skb, tmpl, IP_CT_NEW);
976 		}
977 
978 		state.hook = NF_INET_PRE_ROUTING;
979 		state.net = net;
980 		state.pf = family;
981 		err = nf_conntrack_in(skb, &state);
982 		if (err != NF_ACCEPT)
983 			goto out_push;
984 	}
985 
986 do_nat:
987 	ct = nf_ct_get(skb, &ctinfo);
988 	if (!ct)
989 		goto out_push;
990 	nf_ct_deliver_cached_events(ct);
991 
992 	err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
993 	if (err != NF_ACCEPT)
994 		goto drop;
995 
996 	if (commit) {
997 		tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
998 		tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
999 
1000 		/* This will take care of sending queued events
1001 		 * even if the connection is already confirmed.
1002 		 */
1003 		nf_conntrack_confirm(skb);
1004 	} else if (!skip_add) {
1005 		tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1006 	}
1007 
1008 out_push:
1009 	skb_push_rcsum(skb, nh_ofs);
1010 
1011 out:
1012 	tcf_action_update_bstats(&c->common, skb);
1013 	return retval;
1014 
1015 drop:
1016 	tcf_action_inc_drop_qstats(&c->common);
1017 	return TC_ACT_SHOT;
1018 }
1019 
1020 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1021 	[TCA_CT_ACTION] = { .type = NLA_U16 },
1022 	[TCA_CT_PARMS] = { .type = NLA_EXACT_LEN, .len = sizeof(struct tc_ct) },
1023 	[TCA_CT_ZONE] = { .type = NLA_U16 },
1024 	[TCA_CT_MARK] = { .type = NLA_U32 },
1025 	[TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1026 	[TCA_CT_LABELS] = { .type = NLA_BINARY,
1027 			    .len = 128 / BITS_PER_BYTE },
1028 	[TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1029 				 .len = 128 / BITS_PER_BYTE },
1030 	[TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1031 	[TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1032 	[TCA_CT_NAT_IPV6_MIN] = { .type = NLA_EXACT_LEN,
1033 				  .len = sizeof(struct in6_addr) },
1034 	[TCA_CT_NAT_IPV6_MAX] = { .type = NLA_EXACT_LEN,
1035 				   .len = sizeof(struct in6_addr) },
1036 	[TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1037 	[TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1038 };
1039 
1040 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1041 				  struct tc_ct *parm,
1042 				  struct nlattr **tb,
1043 				  struct netlink_ext_ack *extack)
1044 {
1045 	struct nf_nat_range2 *range;
1046 
1047 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1048 		return 0;
1049 
1050 	if (!IS_ENABLED(CONFIG_NF_NAT)) {
1051 		NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1052 		return -EOPNOTSUPP;
1053 	}
1054 
1055 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1056 		return 0;
1057 
1058 	if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1059 	    (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1060 		NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1061 		return -EOPNOTSUPP;
1062 	}
1063 
1064 	range = &p->range;
1065 	if (tb[TCA_CT_NAT_IPV4_MIN]) {
1066 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1067 
1068 		p->ipv4_range = true;
1069 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1070 		range->min_addr.ip =
1071 			nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1072 
1073 		range->max_addr.ip = max_attr ?
1074 				     nla_get_in_addr(max_attr) :
1075 				     range->min_addr.ip;
1076 	} else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1077 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1078 
1079 		p->ipv4_range = false;
1080 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1081 		range->min_addr.in6 =
1082 			nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1083 
1084 		range->max_addr.in6 = max_attr ?
1085 				      nla_get_in6_addr(max_attr) :
1086 				      range->min_addr.in6;
1087 	}
1088 
1089 	if (tb[TCA_CT_NAT_PORT_MIN]) {
1090 		range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1091 		range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1092 
1093 		range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1094 				       nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1095 				       range->min_proto.all;
1096 	}
1097 
1098 	return 0;
1099 }
1100 
1101 static void tcf_ct_set_key_val(struct nlattr **tb,
1102 			       void *val, int val_type,
1103 			       void *mask, int mask_type,
1104 			       int len)
1105 {
1106 	if (!tb[val_type])
1107 		return;
1108 	nla_memcpy(val, tb[val_type], len);
1109 
1110 	if (!mask)
1111 		return;
1112 
1113 	if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1114 		memset(mask, 0xff, len);
1115 	else
1116 		nla_memcpy(mask, tb[mask_type], len);
1117 }
1118 
1119 static int tcf_ct_fill_params(struct net *net,
1120 			      struct tcf_ct_params *p,
1121 			      struct tc_ct *parm,
1122 			      struct nlattr **tb,
1123 			      struct netlink_ext_ack *extack)
1124 {
1125 	struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1126 	struct nf_conntrack_zone zone;
1127 	struct nf_conn *tmpl;
1128 	int err;
1129 
1130 	p->zone = NF_CT_DEFAULT_ZONE_ID;
1131 
1132 	tcf_ct_set_key_val(tb,
1133 			   &p->ct_action, TCA_CT_ACTION,
1134 			   NULL, TCA_CT_UNSPEC,
1135 			   sizeof(p->ct_action));
1136 
1137 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1138 		return 0;
1139 
1140 	err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1141 	if (err)
1142 		return err;
1143 
1144 	if (tb[TCA_CT_MARK]) {
1145 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1146 			NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1147 			return -EOPNOTSUPP;
1148 		}
1149 		tcf_ct_set_key_val(tb,
1150 				   &p->mark, TCA_CT_MARK,
1151 				   &p->mark_mask, TCA_CT_MARK_MASK,
1152 				   sizeof(p->mark));
1153 	}
1154 
1155 	if (tb[TCA_CT_LABELS]) {
1156 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1157 			NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1158 			return -EOPNOTSUPP;
1159 		}
1160 
1161 		if (!tn->labels) {
1162 			NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1163 			return -EOPNOTSUPP;
1164 		}
1165 		tcf_ct_set_key_val(tb,
1166 				   p->labels, TCA_CT_LABELS,
1167 				   p->labels_mask, TCA_CT_LABELS_MASK,
1168 				   sizeof(p->labels));
1169 	}
1170 
1171 	if (tb[TCA_CT_ZONE]) {
1172 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1173 			NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1174 			return -EOPNOTSUPP;
1175 		}
1176 
1177 		tcf_ct_set_key_val(tb,
1178 				   &p->zone, TCA_CT_ZONE,
1179 				   NULL, TCA_CT_UNSPEC,
1180 				   sizeof(p->zone));
1181 	}
1182 
1183 	if (p->zone == NF_CT_DEFAULT_ZONE_ID)
1184 		return 0;
1185 
1186 	nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1187 	tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1188 	if (!tmpl) {
1189 		NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1190 		return -ENOMEM;
1191 	}
1192 	__set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1193 	nf_conntrack_get(&tmpl->ct_general);
1194 	p->tmpl = tmpl;
1195 
1196 	return 0;
1197 }
1198 
1199 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1200 		       struct nlattr *est, struct tc_action **a,
1201 		       int replace, int bind, bool rtnl_held,
1202 		       struct tcf_proto *tp, u32 flags,
1203 		       struct netlink_ext_ack *extack)
1204 {
1205 	struct tc_action_net *tn = net_generic(net, ct_net_id);
1206 	struct tcf_ct_params *params = NULL;
1207 	struct nlattr *tb[TCA_CT_MAX + 1];
1208 	struct tcf_chain *goto_ch = NULL;
1209 	struct tc_ct *parm;
1210 	struct tcf_ct *c;
1211 	int err, res = 0;
1212 	u32 index;
1213 
1214 	if (!nla) {
1215 		NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1216 		return -EINVAL;
1217 	}
1218 
1219 	err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1220 	if (err < 0)
1221 		return err;
1222 
1223 	if (!tb[TCA_CT_PARMS]) {
1224 		NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1225 		return -EINVAL;
1226 	}
1227 	parm = nla_data(tb[TCA_CT_PARMS]);
1228 	index = parm->index;
1229 	err = tcf_idr_check_alloc(tn, &index, a, bind);
1230 	if (err < 0)
1231 		return err;
1232 
1233 	if (!err) {
1234 		err = tcf_idr_create_from_flags(tn, index, est, a,
1235 						&act_ct_ops, bind, flags);
1236 		if (err) {
1237 			tcf_idr_cleanup(tn, index);
1238 			return err;
1239 		}
1240 		res = ACT_P_CREATED;
1241 	} else {
1242 		if (bind)
1243 			return 0;
1244 
1245 		if (!replace) {
1246 			tcf_idr_release(*a, bind);
1247 			return -EEXIST;
1248 		}
1249 	}
1250 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1251 	if (err < 0)
1252 		goto cleanup;
1253 
1254 	c = to_ct(*a);
1255 
1256 	params = kzalloc(sizeof(*params), GFP_KERNEL);
1257 	if (unlikely(!params)) {
1258 		err = -ENOMEM;
1259 		goto cleanup;
1260 	}
1261 
1262 	err = tcf_ct_fill_params(net, params, parm, tb, extack);
1263 	if (err)
1264 		goto cleanup;
1265 
1266 	err = tcf_ct_flow_table_get(params);
1267 	if (err)
1268 		goto cleanup;
1269 
1270 	spin_lock_bh(&c->tcf_lock);
1271 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1272 	params = rcu_replace_pointer(c->params, params,
1273 				     lockdep_is_held(&c->tcf_lock));
1274 	spin_unlock_bh(&c->tcf_lock);
1275 
1276 	if (goto_ch)
1277 		tcf_chain_put_by_act(goto_ch);
1278 	if (params)
1279 		call_rcu(&params->rcu, tcf_ct_params_free);
1280 	if (res == ACT_P_CREATED)
1281 		tcf_idr_insert(tn, *a);
1282 
1283 	return res;
1284 
1285 cleanup:
1286 	if (goto_ch)
1287 		tcf_chain_put_by_act(goto_ch);
1288 	kfree(params);
1289 	tcf_idr_release(*a, bind);
1290 	return err;
1291 }
1292 
1293 static void tcf_ct_cleanup(struct tc_action *a)
1294 {
1295 	struct tcf_ct_params *params;
1296 	struct tcf_ct *c = to_ct(a);
1297 
1298 	params = rcu_dereference_protected(c->params, 1);
1299 	if (params)
1300 		call_rcu(&params->rcu, tcf_ct_params_free);
1301 }
1302 
1303 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1304 			       void *val, int val_type,
1305 			       void *mask, int mask_type,
1306 			       int len)
1307 {
1308 	int err;
1309 
1310 	if (mask && !memchr_inv(mask, 0, len))
1311 		return 0;
1312 
1313 	err = nla_put(skb, val_type, len, val);
1314 	if (err)
1315 		return err;
1316 
1317 	if (mask_type != TCA_CT_UNSPEC) {
1318 		err = nla_put(skb, mask_type, len, mask);
1319 		if (err)
1320 			return err;
1321 	}
1322 
1323 	return 0;
1324 }
1325 
1326 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1327 {
1328 	struct nf_nat_range2 *range = &p->range;
1329 
1330 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1331 		return 0;
1332 
1333 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1334 		return 0;
1335 
1336 	if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1337 		if (p->ipv4_range) {
1338 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1339 					    range->min_addr.ip))
1340 				return -1;
1341 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1342 					    range->max_addr.ip))
1343 				return -1;
1344 		} else {
1345 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1346 					     &range->min_addr.in6))
1347 				return -1;
1348 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1349 					     &range->max_addr.in6))
1350 				return -1;
1351 		}
1352 	}
1353 
1354 	if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1355 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1356 				 range->min_proto.all))
1357 			return -1;
1358 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1359 				 range->max_proto.all))
1360 			return -1;
1361 	}
1362 
1363 	return 0;
1364 }
1365 
1366 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1367 			      int bind, int ref)
1368 {
1369 	unsigned char *b = skb_tail_pointer(skb);
1370 	struct tcf_ct *c = to_ct(a);
1371 	struct tcf_ct_params *p;
1372 
1373 	struct tc_ct opt = {
1374 		.index   = c->tcf_index,
1375 		.refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1376 		.bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1377 	};
1378 	struct tcf_t t;
1379 
1380 	spin_lock_bh(&c->tcf_lock);
1381 	p = rcu_dereference_protected(c->params,
1382 				      lockdep_is_held(&c->tcf_lock));
1383 	opt.action = c->tcf_action;
1384 
1385 	if (tcf_ct_dump_key_val(skb,
1386 				&p->ct_action, TCA_CT_ACTION,
1387 				NULL, TCA_CT_UNSPEC,
1388 				sizeof(p->ct_action)))
1389 		goto nla_put_failure;
1390 
1391 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1392 		goto skip_dump;
1393 
1394 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1395 	    tcf_ct_dump_key_val(skb,
1396 				&p->mark, TCA_CT_MARK,
1397 				&p->mark_mask, TCA_CT_MARK_MASK,
1398 				sizeof(p->mark)))
1399 		goto nla_put_failure;
1400 
1401 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1402 	    tcf_ct_dump_key_val(skb,
1403 				p->labels, TCA_CT_LABELS,
1404 				p->labels_mask, TCA_CT_LABELS_MASK,
1405 				sizeof(p->labels)))
1406 		goto nla_put_failure;
1407 
1408 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1409 	    tcf_ct_dump_key_val(skb,
1410 				&p->zone, TCA_CT_ZONE,
1411 				NULL, TCA_CT_UNSPEC,
1412 				sizeof(p->zone)))
1413 		goto nla_put_failure;
1414 
1415 	if (tcf_ct_dump_nat(skb, p))
1416 		goto nla_put_failure;
1417 
1418 skip_dump:
1419 	if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1420 		goto nla_put_failure;
1421 
1422 	tcf_tm_dump(&t, &c->tcf_tm);
1423 	if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1424 		goto nla_put_failure;
1425 	spin_unlock_bh(&c->tcf_lock);
1426 
1427 	return skb->len;
1428 nla_put_failure:
1429 	spin_unlock_bh(&c->tcf_lock);
1430 	nlmsg_trim(skb, b);
1431 	return -1;
1432 }
1433 
1434 static int tcf_ct_walker(struct net *net, struct sk_buff *skb,
1435 			 struct netlink_callback *cb, int type,
1436 			 const struct tc_action_ops *ops,
1437 			 struct netlink_ext_ack *extack)
1438 {
1439 	struct tc_action_net *tn = net_generic(net, ct_net_id);
1440 
1441 	return tcf_generic_walker(tn, skb, cb, type, ops, extack);
1442 }
1443 
1444 static int tcf_ct_search(struct net *net, struct tc_action **a, u32 index)
1445 {
1446 	struct tc_action_net *tn = net_generic(net, ct_net_id);
1447 
1448 	return tcf_idr_search(tn, a, index);
1449 }
1450 
1451 static void tcf_stats_update(struct tc_action *a, u64 bytes, u32 packets,
1452 			     u64 lastuse, bool hw)
1453 {
1454 	struct tcf_ct *c = to_ct(a);
1455 
1456 	tcf_action_update_stats(a, bytes, packets, false, hw);
1457 	c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1458 }
1459 
1460 static struct tc_action_ops act_ct_ops = {
1461 	.kind		=	"ct",
1462 	.id		=	TCA_ID_CT,
1463 	.owner		=	THIS_MODULE,
1464 	.act		=	tcf_ct_act,
1465 	.dump		=	tcf_ct_dump,
1466 	.init		=	tcf_ct_init,
1467 	.cleanup	=	tcf_ct_cleanup,
1468 	.walk		=	tcf_ct_walker,
1469 	.lookup		=	tcf_ct_search,
1470 	.stats_update	=	tcf_stats_update,
1471 	.size		=	sizeof(struct tcf_ct),
1472 };
1473 
1474 static __net_init int ct_init_net(struct net *net)
1475 {
1476 	unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1477 	struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1478 
1479 	if (nf_connlabels_get(net, n_bits - 1)) {
1480 		tn->labels = false;
1481 		pr_err("act_ct: Failed to set connlabels length");
1482 	} else {
1483 		tn->labels = true;
1484 	}
1485 
1486 	return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1487 }
1488 
1489 static void __net_exit ct_exit_net(struct list_head *net_list)
1490 {
1491 	struct net *net;
1492 
1493 	rtnl_lock();
1494 	list_for_each_entry(net, net_list, exit_list) {
1495 		struct tc_ct_action_net *tn = net_generic(net, ct_net_id);
1496 
1497 		if (tn->labels)
1498 			nf_connlabels_put(net);
1499 	}
1500 	rtnl_unlock();
1501 
1502 	tc_action_net_exit(net_list, ct_net_id);
1503 }
1504 
1505 static struct pernet_operations ct_net_ops = {
1506 	.init = ct_init_net,
1507 	.exit_batch = ct_exit_net,
1508 	.id   = &ct_net_id,
1509 	.size = sizeof(struct tc_ct_action_net),
1510 };
1511 
1512 static int __init ct_init_module(void)
1513 {
1514 	int err;
1515 
1516 	act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1517 	if (!act_ct_wq)
1518 		return -ENOMEM;
1519 
1520 	err = tcf_ct_flow_tables_init();
1521 	if (err)
1522 		goto err_tbl_init;
1523 
1524 	err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1525 	if (err)
1526 		goto err_register;
1527 
1528 	return 0;
1529 
1530 err_tbl_init:
1531 	destroy_workqueue(act_ct_wq);
1532 err_register:
1533 	tcf_ct_flow_tables_uninit();
1534 	return err;
1535 }
1536 
1537 static void __exit ct_cleanup_module(void)
1538 {
1539 	tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1540 	tcf_ct_flow_tables_uninit();
1541 	destroy_workqueue(act_ct_wq);
1542 }
1543 
1544 void tcf_ct_flow_table_restore_skb(struct sk_buff *skb, unsigned long cookie)
1545 {
1546 	enum ip_conntrack_info ctinfo = cookie & NFCT_INFOMASK;
1547 	struct nf_conn *ct;
1548 
1549 	ct = (struct nf_conn *)(cookie & NFCT_PTRMASK);
1550 	nf_conntrack_get(&ct->ct_general);
1551 	nf_ct_set(skb, ct, ctinfo);
1552 }
1553 EXPORT_SYMBOL_GPL(tcf_ct_flow_table_restore_skb);
1554 
1555 module_init(ct_init_module);
1556 module_exit(ct_cleanup_module);
1557 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1558 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1559 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1560 MODULE_DESCRIPTION("Connection tracking action");
1561 MODULE_LICENSE("GPL v2");
1562 
1563