xref: /linux/net/sched/act_ct.c (revision da51bbcdbace8f43adf6066934c3926b656376e5)
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 #include <net/tc_wrapper.h>
28 
29 #include <net/netfilter/nf_flow_table.h>
30 #include <net/netfilter/nf_conntrack.h>
31 #include <net/netfilter/nf_conntrack_core.h>
32 #include <net/netfilter/nf_conntrack_zones.h>
33 #include <net/netfilter/nf_conntrack_helper.h>
34 #include <net/netfilter/nf_conntrack_acct.h>
35 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
36 #include <net/netfilter/nf_conntrack_act_ct.h>
37 #include <net/netfilter/nf_conntrack_seqadj.h>
38 #include <uapi/linux/netfilter/nf_nat.h>
39 
40 static struct workqueue_struct *act_ct_wq;
41 static struct rhashtable zones_ht;
42 static DEFINE_MUTEX(zones_mutex);
43 
44 struct tcf_ct_flow_table {
45 	struct rhash_head node; /* In zones tables */
46 
47 	struct rcu_work rwork;
48 	struct nf_flowtable nf_ft;
49 	refcount_t ref;
50 	u16 zone;
51 
52 	bool dying;
53 };
54 
55 static const struct rhashtable_params zones_params = {
56 	.head_offset = offsetof(struct tcf_ct_flow_table, node),
57 	.key_offset = offsetof(struct tcf_ct_flow_table, zone),
58 	.key_len = sizeof_field(struct tcf_ct_flow_table, zone),
59 	.automatic_shrinking = true,
60 };
61 
62 static struct flow_action_entry *
63 tcf_ct_flow_table_flow_action_get_next(struct flow_action *flow_action)
64 {
65 	int i = flow_action->num_entries++;
66 
67 	return &flow_action->entries[i];
68 }
69 
70 static void tcf_ct_add_mangle_action(struct flow_action *action,
71 				     enum flow_action_mangle_base htype,
72 				     u32 offset,
73 				     u32 mask,
74 				     u32 val)
75 {
76 	struct flow_action_entry *entry;
77 
78 	entry = tcf_ct_flow_table_flow_action_get_next(action);
79 	entry->id = FLOW_ACTION_MANGLE;
80 	entry->mangle.htype = htype;
81 	entry->mangle.mask = ~mask;
82 	entry->mangle.offset = offset;
83 	entry->mangle.val = val;
84 }
85 
86 /* The following nat helper functions check if the inverted reverse tuple
87  * (target) is different then the current dir tuple - meaning nat for ports
88  * and/or ip is needed, and add the relevant mangle actions.
89  */
90 static void
91 tcf_ct_flow_table_add_action_nat_ipv4(const struct nf_conntrack_tuple *tuple,
92 				      struct nf_conntrack_tuple target,
93 				      struct flow_action *action)
94 {
95 	if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
96 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
97 					 offsetof(struct iphdr, saddr),
98 					 0xFFFFFFFF,
99 					 be32_to_cpu(target.src.u3.ip));
100 	if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
101 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP4,
102 					 offsetof(struct iphdr, daddr),
103 					 0xFFFFFFFF,
104 					 be32_to_cpu(target.dst.u3.ip));
105 }
106 
107 static void
108 tcf_ct_add_ipv6_addr_mangle_action(struct flow_action *action,
109 				   union nf_inet_addr *addr,
110 				   u32 offset)
111 {
112 	int i;
113 
114 	for (i = 0; i < sizeof(struct in6_addr) / sizeof(u32); i++)
115 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
116 					 i * sizeof(u32) + offset,
117 					 0xFFFFFFFF, be32_to_cpu(addr->ip6[i]));
118 }
119 
120 static void
121 tcf_ct_flow_table_add_action_nat_ipv6(const struct nf_conntrack_tuple *tuple,
122 				      struct nf_conntrack_tuple target,
123 				      struct flow_action *action)
124 {
125 	if (memcmp(&target.src.u3, &tuple->src.u3, sizeof(target.src.u3)))
126 		tcf_ct_add_ipv6_addr_mangle_action(action, &target.src.u3,
127 						   offsetof(struct ipv6hdr,
128 							    saddr));
129 	if (memcmp(&target.dst.u3, &tuple->dst.u3, sizeof(target.dst.u3)))
130 		tcf_ct_add_ipv6_addr_mangle_action(action, &target.dst.u3,
131 						   offsetof(struct ipv6hdr,
132 							    daddr));
133 }
134 
135 static void
136 tcf_ct_flow_table_add_action_nat_tcp(const struct nf_conntrack_tuple *tuple,
137 				     struct nf_conntrack_tuple target,
138 				     struct flow_action *action)
139 {
140 	__be16 target_src = target.src.u.tcp.port;
141 	__be16 target_dst = target.dst.u.tcp.port;
142 
143 	if (target_src != tuple->src.u.tcp.port)
144 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
145 					 offsetof(struct tcphdr, source),
146 					 0xFFFF, be16_to_cpu(target_src));
147 	if (target_dst != tuple->dst.u.tcp.port)
148 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_TCP,
149 					 offsetof(struct tcphdr, dest),
150 					 0xFFFF, be16_to_cpu(target_dst));
151 }
152 
153 static void
154 tcf_ct_flow_table_add_action_nat_udp(const struct nf_conntrack_tuple *tuple,
155 				     struct nf_conntrack_tuple target,
156 				     struct flow_action *action)
157 {
158 	__be16 target_src = target.src.u.udp.port;
159 	__be16 target_dst = target.dst.u.udp.port;
160 
161 	if (target_src != tuple->src.u.udp.port)
162 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
163 					 offsetof(struct udphdr, source),
164 					 0xFFFF, be16_to_cpu(target_src));
165 	if (target_dst != tuple->dst.u.udp.port)
166 		tcf_ct_add_mangle_action(action, FLOW_ACT_MANGLE_HDR_TYPE_UDP,
167 					 offsetof(struct udphdr, dest),
168 					 0xFFFF, be16_to_cpu(target_dst));
169 }
170 
171 static void tcf_ct_flow_table_add_action_meta(struct nf_conn *ct,
172 					      enum ip_conntrack_dir dir,
173 					      enum ip_conntrack_info ctinfo,
174 					      struct flow_action *action)
175 {
176 	struct nf_conn_labels *ct_labels;
177 	struct flow_action_entry *entry;
178 	u32 *act_ct_labels;
179 
180 	entry = tcf_ct_flow_table_flow_action_get_next(action);
181 	entry->id = FLOW_ACTION_CT_METADATA;
182 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
183 	entry->ct_metadata.mark = READ_ONCE(ct->mark);
184 #endif
185 	/* aligns with the CT reference on the SKB nf_ct_set */
186 	entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
187 	entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL;
188 
189 	act_ct_labels = entry->ct_metadata.labels;
190 	ct_labels = nf_ct_labels_find(ct);
191 	if (ct_labels)
192 		memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
193 	else
194 		memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
195 }
196 
197 static int tcf_ct_flow_table_add_action_nat(struct net *net,
198 					    struct nf_conn *ct,
199 					    enum ip_conntrack_dir dir,
200 					    struct flow_action *action)
201 {
202 	const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
203 	struct nf_conntrack_tuple target;
204 
205 	if (!(ct->status & IPS_NAT_MASK))
206 		return 0;
207 
208 	nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
209 
210 	switch (tuple->src.l3num) {
211 	case NFPROTO_IPV4:
212 		tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
213 						      action);
214 		break;
215 	case NFPROTO_IPV6:
216 		tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
217 						      action);
218 		break;
219 	default:
220 		return -EOPNOTSUPP;
221 	}
222 
223 	switch (nf_ct_protonum(ct)) {
224 	case IPPROTO_TCP:
225 		tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
226 		break;
227 	case IPPROTO_UDP:
228 		tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
229 		break;
230 	default:
231 		return -EOPNOTSUPP;
232 	}
233 
234 	return 0;
235 }
236 
237 static int tcf_ct_flow_table_fill_actions(struct net *net,
238 					  struct flow_offload *flow,
239 					  enum flow_offload_tuple_dir tdir,
240 					  struct nf_flow_rule *flow_rule)
241 {
242 	struct flow_action *action = &flow_rule->rule->action;
243 	int num_entries = action->num_entries;
244 	struct nf_conn *ct = flow->ct;
245 	enum ip_conntrack_info ctinfo;
246 	enum ip_conntrack_dir dir;
247 	int i, err;
248 
249 	switch (tdir) {
250 	case FLOW_OFFLOAD_DIR_ORIGINAL:
251 		dir = IP_CT_DIR_ORIGINAL;
252 		ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ?
253 			IP_CT_ESTABLISHED : IP_CT_NEW;
254 		if (ctinfo == IP_CT_ESTABLISHED)
255 			set_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags);
256 		break;
257 	case FLOW_OFFLOAD_DIR_REPLY:
258 		dir = IP_CT_DIR_REPLY;
259 		ctinfo = IP_CT_ESTABLISHED_REPLY;
260 		break;
261 	default:
262 		return -EOPNOTSUPP;
263 	}
264 
265 	err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
266 	if (err)
267 		goto err_nat;
268 
269 	tcf_ct_flow_table_add_action_meta(ct, dir, ctinfo, action);
270 	return 0;
271 
272 err_nat:
273 	/* Clear filled actions */
274 	for (i = num_entries; i < action->num_entries; i++)
275 		memset(&action->entries[i], 0, sizeof(action->entries[i]));
276 	action->num_entries = num_entries;
277 
278 	return err;
279 }
280 
281 static bool tcf_ct_flow_is_outdated(const struct flow_offload *flow)
282 {
283 	return test_bit(IPS_SEEN_REPLY_BIT, &flow->ct->status) &&
284 	       test_bit(IPS_HW_OFFLOAD_BIT, &flow->ct->status) &&
285 	       !test_bit(NF_FLOW_HW_PENDING, &flow->flags) &&
286 	       !test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags);
287 }
288 
289 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft);
290 
291 static void tcf_ct_nf_get(struct nf_flowtable *ft)
292 {
293 	struct tcf_ct_flow_table *ct_ft =
294 		container_of(ft, struct tcf_ct_flow_table, nf_ft);
295 
296 	tcf_ct_flow_table_get_ref(ct_ft);
297 }
298 
299 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft);
300 
301 static void tcf_ct_nf_put(struct nf_flowtable *ft)
302 {
303 	struct tcf_ct_flow_table *ct_ft =
304 		container_of(ft, struct tcf_ct_flow_table, nf_ft);
305 
306 	tcf_ct_flow_table_put(ct_ft);
307 }
308 
309 static struct nf_flowtable_type flowtable_ct = {
310 	.gc		= tcf_ct_flow_is_outdated,
311 	.action		= tcf_ct_flow_table_fill_actions,
312 	.get		= tcf_ct_nf_get,
313 	.put		= tcf_ct_nf_put,
314 	.owner		= THIS_MODULE,
315 };
316 
317 static int tcf_ct_flow_table_get(struct net *net, struct tcf_ct_params *params)
318 {
319 	struct tcf_ct_flow_table *ct_ft;
320 	int err = -ENOMEM;
321 
322 	mutex_lock(&zones_mutex);
323 	ct_ft = rhashtable_lookup_fast(&zones_ht, &params->zone, zones_params);
324 	if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
325 		goto out_unlock;
326 
327 	ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
328 	if (!ct_ft)
329 		goto err_alloc;
330 	refcount_set(&ct_ft->ref, 1);
331 
332 	ct_ft->zone = params->zone;
333 	err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
334 	if (err)
335 		goto err_insert;
336 
337 	ct_ft->nf_ft.type = &flowtable_ct;
338 	ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD |
339 			      NF_FLOWTABLE_COUNTER;
340 	err = nf_flow_table_init(&ct_ft->nf_ft);
341 	if (err)
342 		goto err_init;
343 	write_pnet(&ct_ft->nf_ft.net, net);
344 
345 	__module_get(THIS_MODULE);
346 out_unlock:
347 	params->ct_ft = ct_ft;
348 	params->nf_ft = &ct_ft->nf_ft;
349 	mutex_unlock(&zones_mutex);
350 
351 	return 0;
352 
353 err_init:
354 	rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
355 err_insert:
356 	kfree(ct_ft);
357 err_alloc:
358 	mutex_unlock(&zones_mutex);
359 	return err;
360 }
361 
362 static void tcf_ct_flow_table_get_ref(struct tcf_ct_flow_table *ct_ft)
363 {
364 	refcount_inc(&ct_ft->ref);
365 }
366 
367 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
368 {
369 	struct tcf_ct_flow_table *ct_ft;
370 	struct flow_block *block;
371 
372 	ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
373 			     rwork);
374 	nf_flow_table_free(&ct_ft->nf_ft);
375 
376 	block = &ct_ft->nf_ft.flow_block;
377 	down_write(&ct_ft->nf_ft.flow_block_lock);
378 	WARN_ON(!list_empty(&block->cb_list));
379 	up_write(&ct_ft->nf_ft.flow_block_lock);
380 	kfree(ct_ft);
381 
382 	module_put(THIS_MODULE);
383 }
384 
385 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft)
386 {
387 	if (refcount_dec_and_test(&ct_ft->ref)) {
388 		rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
389 		INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
390 		queue_rcu_work(act_ct_wq, &ct_ft->rwork);
391 	}
392 }
393 
394 static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry,
395 				 struct nf_conn_act_ct_ext *act_ct_ext, u8 dir)
396 {
397 	entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC;
398 	entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir];
399 }
400 
401 static void tcf_ct_flow_ct_ext_ifidx_update(struct flow_offload *entry)
402 {
403 	struct nf_conn_act_ct_ext *act_ct_ext;
404 
405 	act_ct_ext = nf_conn_act_ct_ext_find(entry->ct);
406 	if (act_ct_ext) {
407 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
408 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
409 	}
410 }
411 
412 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
413 				  struct nf_conn *ct,
414 				  bool tcp, bool bidirectional)
415 {
416 	struct nf_conn_act_ct_ext *act_ct_ext;
417 	struct flow_offload *entry;
418 	int err;
419 
420 	if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
421 		return;
422 
423 	entry = flow_offload_alloc(ct);
424 	if (!entry) {
425 		WARN_ON_ONCE(1);
426 		goto err_alloc;
427 	}
428 
429 	if (tcp) {
430 		ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
431 		ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
432 	}
433 	if (bidirectional)
434 		__set_bit(NF_FLOW_HW_BIDIRECTIONAL, &entry->flags);
435 
436 	act_ct_ext = nf_conn_act_ct_ext_find(ct);
437 	if (act_ct_ext) {
438 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
439 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
440 	}
441 
442 	err = flow_offload_add(&ct_ft->nf_ft, entry);
443 	if (err)
444 		goto err_add;
445 
446 	return;
447 
448 err_add:
449 	flow_offload_free(entry);
450 err_alloc:
451 	clear_bit(IPS_OFFLOAD_BIT, &ct->status);
452 }
453 
454 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
455 					   struct nf_conn *ct,
456 					   enum ip_conntrack_info ctinfo)
457 {
458 	bool tcp = false, bidirectional = true;
459 
460 	switch (nf_ct_protonum(ct)) {
461 	case IPPROTO_TCP:
462 		if ((ctinfo != IP_CT_ESTABLISHED &&
463 		     ctinfo != IP_CT_ESTABLISHED_REPLY) ||
464 		    !test_bit(IPS_ASSURED_BIT, &ct->status) ||
465 		    ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
466 			return;
467 
468 		tcp = true;
469 		break;
470 	case IPPROTO_UDP:
471 		if (!nf_ct_is_confirmed(ct))
472 			return;
473 		if (!test_bit(IPS_ASSURED_BIT, &ct->status))
474 			bidirectional = false;
475 		break;
476 #ifdef CONFIG_NF_CT_PROTO_GRE
477 	case IPPROTO_GRE: {
478 		struct nf_conntrack_tuple *tuple;
479 
480 		if ((ctinfo != IP_CT_ESTABLISHED &&
481 		     ctinfo != IP_CT_ESTABLISHED_REPLY) ||
482 		    !test_bit(IPS_ASSURED_BIT, &ct->status) ||
483 		    ct->status & IPS_NAT_MASK)
484 			return;
485 
486 		tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
487 		/* No support for GRE v1 */
488 		if (tuple->src.u.gre.key || tuple->dst.u.gre.key)
489 			return;
490 		break;
491 	}
492 #endif
493 	default:
494 		return;
495 	}
496 
497 	if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
498 	    ct->status & IPS_SEQ_ADJUST)
499 		return;
500 
501 	tcf_ct_flow_table_add(ct_ft, ct, tcp, bidirectional);
502 }
503 
504 static bool
505 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
506 				  struct flow_offload_tuple *tuple,
507 				  struct tcphdr **tcph)
508 {
509 	struct flow_ports *ports;
510 	unsigned int thoff;
511 	struct iphdr *iph;
512 	size_t hdrsize;
513 	u8 ipproto;
514 
515 	if (!pskb_network_may_pull(skb, sizeof(*iph)))
516 		return false;
517 
518 	iph = ip_hdr(skb);
519 	thoff = iph->ihl * 4;
520 
521 	if (ip_is_fragment(iph) ||
522 	    unlikely(thoff != sizeof(struct iphdr)))
523 		return false;
524 
525 	ipproto = iph->protocol;
526 	switch (ipproto) {
527 	case IPPROTO_TCP:
528 		hdrsize = sizeof(struct tcphdr);
529 		break;
530 	case IPPROTO_UDP:
531 		hdrsize = sizeof(*ports);
532 		break;
533 #ifdef CONFIG_NF_CT_PROTO_GRE
534 	case IPPROTO_GRE:
535 		hdrsize = sizeof(struct gre_base_hdr);
536 		break;
537 #endif
538 	default:
539 		return false;
540 	}
541 
542 	if (iph->ttl <= 1)
543 		return false;
544 
545 	if (!pskb_network_may_pull(skb, thoff + hdrsize))
546 		return false;
547 
548 	switch (ipproto) {
549 	case IPPROTO_TCP:
550 		*tcph = (void *)(skb_network_header(skb) + thoff);
551 		fallthrough;
552 	case IPPROTO_UDP:
553 		ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
554 		tuple->src_port = ports->source;
555 		tuple->dst_port = ports->dest;
556 		break;
557 	case IPPROTO_GRE: {
558 		struct gre_base_hdr *greh;
559 
560 		greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
561 		if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
562 			return false;
563 		break;
564 	}
565 	}
566 
567 	iph = ip_hdr(skb);
568 
569 	tuple->src_v4.s_addr = iph->saddr;
570 	tuple->dst_v4.s_addr = iph->daddr;
571 	tuple->l3proto = AF_INET;
572 	tuple->l4proto = ipproto;
573 
574 	return true;
575 }
576 
577 static bool
578 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
579 				  struct flow_offload_tuple *tuple,
580 				  struct tcphdr **tcph)
581 {
582 	struct flow_ports *ports;
583 	struct ipv6hdr *ip6h;
584 	unsigned int thoff;
585 	size_t hdrsize;
586 	u8 nexthdr;
587 
588 	if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
589 		return false;
590 
591 	ip6h = ipv6_hdr(skb);
592 	thoff = sizeof(*ip6h);
593 
594 	nexthdr = ip6h->nexthdr;
595 	switch (nexthdr) {
596 	case IPPROTO_TCP:
597 		hdrsize = sizeof(struct tcphdr);
598 		break;
599 	case IPPROTO_UDP:
600 		hdrsize = sizeof(*ports);
601 		break;
602 #ifdef CONFIG_NF_CT_PROTO_GRE
603 	case IPPROTO_GRE:
604 		hdrsize = sizeof(struct gre_base_hdr);
605 		break;
606 #endif
607 	default:
608 		return false;
609 	}
610 
611 	if (ip6h->hop_limit <= 1)
612 		return false;
613 
614 	if (!pskb_network_may_pull(skb, thoff + hdrsize))
615 		return false;
616 
617 	switch (nexthdr) {
618 	case IPPROTO_TCP:
619 		*tcph = (void *)(skb_network_header(skb) + thoff);
620 		fallthrough;
621 	case IPPROTO_UDP:
622 		ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
623 		tuple->src_port = ports->source;
624 		tuple->dst_port = ports->dest;
625 		break;
626 	case IPPROTO_GRE: {
627 		struct gre_base_hdr *greh;
628 
629 		greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
630 		if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
631 			return false;
632 		break;
633 	}
634 	}
635 
636 	ip6h = ipv6_hdr(skb);
637 
638 	tuple->src_v6 = ip6h->saddr;
639 	tuple->dst_v6 = ip6h->daddr;
640 	tuple->l3proto = AF_INET6;
641 	tuple->l4proto = nexthdr;
642 
643 	return true;
644 }
645 
646 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
647 				     struct sk_buff *skb,
648 				     u8 family)
649 {
650 	struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
651 	struct flow_offload_tuple_rhash *tuplehash;
652 	struct flow_offload_tuple tuple = {};
653 	enum ip_conntrack_info ctinfo;
654 	struct tcphdr *tcph = NULL;
655 	bool force_refresh = false;
656 	struct flow_offload *flow;
657 	struct nf_conn *ct;
658 	u8 dir;
659 
660 	switch (family) {
661 	case NFPROTO_IPV4:
662 		if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
663 			return false;
664 		break;
665 	case NFPROTO_IPV6:
666 		if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
667 			return false;
668 		break;
669 	default:
670 		return false;
671 	}
672 
673 	tuplehash = flow_offload_lookup(nf_ft, &tuple);
674 	if (!tuplehash)
675 		return false;
676 
677 	dir = tuplehash->tuple.dir;
678 	flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
679 	ct = flow->ct;
680 
681 	if (dir == FLOW_OFFLOAD_DIR_REPLY &&
682 	    !test_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags)) {
683 		/* Only offload reply direction after connection became
684 		 * assured.
685 		 */
686 		if (test_bit(IPS_ASSURED_BIT, &ct->status))
687 			set_bit(NF_FLOW_HW_BIDIRECTIONAL, &flow->flags);
688 		else if (test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags))
689 			/* If flow_table flow has already been updated to the
690 			 * established state, then don't refresh.
691 			 */
692 			return false;
693 		force_refresh = true;
694 	}
695 
696 	if (tcph && (unlikely(tcph->fin || tcph->rst))) {
697 		flow_offload_teardown(flow);
698 		return false;
699 	}
700 
701 	if (dir == FLOW_OFFLOAD_DIR_ORIGINAL)
702 		ctinfo = test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ?
703 			IP_CT_ESTABLISHED : IP_CT_NEW;
704 	else
705 		ctinfo = IP_CT_ESTABLISHED_REPLY;
706 
707 	nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
708 	tcf_ct_flow_ct_ext_ifidx_update(flow);
709 	flow_offload_refresh(nf_ft, flow, force_refresh);
710 	if (!test_bit(IPS_ASSURED_BIT, &ct->status)) {
711 		/* Process this flow in SW to allow promoting to ASSURED */
712 		return false;
713 	}
714 
715 	nf_conntrack_get(&ct->ct_general);
716 	nf_ct_set(skb, ct, ctinfo);
717 	if (nf_ft->flags & NF_FLOWTABLE_COUNTER)
718 		nf_ct_acct_update(ct, dir, skb->len);
719 
720 	return true;
721 }
722 
723 static int tcf_ct_flow_tables_init(void)
724 {
725 	return rhashtable_init(&zones_ht, &zones_params);
726 }
727 
728 static void tcf_ct_flow_tables_uninit(void)
729 {
730 	rhashtable_destroy(&zones_ht);
731 }
732 
733 static struct tc_action_ops act_ct_ops;
734 
735 struct tc_ct_action_net {
736 	struct tc_action_net tn; /* Must be first */
737 };
738 
739 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
740 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
741 				   struct tcf_ct_params *p)
742 {
743 	enum ip_conntrack_info ctinfo;
744 	struct nf_conn *ct;
745 
746 	ct = nf_ct_get(skb, &ctinfo);
747 	if (!ct)
748 		return false;
749 	if (!net_eq(net, read_pnet(&ct->ct_net)))
750 		goto drop_ct;
751 	if (nf_ct_zone(ct)->id != p->zone)
752 		goto drop_ct;
753 	if (p->helper) {
754 		struct nf_conn_help *help;
755 
756 		help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
757 		if (help && rcu_access_pointer(help->helper) != p->helper)
758 			goto drop_ct;
759 	}
760 
761 	/* Force conntrack entry direction. */
762 	if ((p->ct_action & TCA_CT_ACT_FORCE) &&
763 	    CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
764 		if (nf_ct_is_confirmed(ct))
765 			nf_ct_kill(ct);
766 
767 		goto drop_ct;
768 	}
769 
770 	return true;
771 
772 drop_ct:
773 	nf_ct_put(ct);
774 	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
775 
776 	return false;
777 }
778 
779 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
780 {
781 	u8 family = NFPROTO_UNSPEC;
782 
783 	switch (skb_protocol(skb, true)) {
784 	case htons(ETH_P_IP):
785 		family = NFPROTO_IPV4;
786 		break;
787 	case htons(ETH_P_IPV6):
788 		family = NFPROTO_IPV6;
789 		break;
790 	default:
791 		break;
792 	}
793 
794 	return family;
795 }
796 
797 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
798 {
799 	unsigned int len;
800 
801 	len =  skb_network_offset(skb) + sizeof(struct iphdr);
802 	if (unlikely(skb->len < len))
803 		return -EINVAL;
804 	if (unlikely(!pskb_may_pull(skb, len)))
805 		return -ENOMEM;
806 
807 	*frag = ip_is_fragment(ip_hdr(skb));
808 	return 0;
809 }
810 
811 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
812 {
813 	unsigned int flags = 0, len, payload_ofs = 0;
814 	unsigned short frag_off;
815 	int nexthdr;
816 
817 	len =  skb_network_offset(skb) + sizeof(struct ipv6hdr);
818 	if (unlikely(skb->len < len))
819 		return -EINVAL;
820 	if (unlikely(!pskb_may_pull(skb, len)))
821 		return -ENOMEM;
822 
823 	nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
824 	if (unlikely(nexthdr < 0))
825 		return -EPROTO;
826 
827 	*frag = flags & IP6_FH_F_FRAG;
828 	return 0;
829 }
830 
831 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
832 				   u8 family, u16 zone, bool *defrag)
833 {
834 	enum ip_conntrack_info ctinfo;
835 	struct nf_conn *ct;
836 	int err = 0;
837 	bool frag;
838 	u8 proto;
839 	u16 mru;
840 
841 	/* Previously seen (loopback)? Ignore. */
842 	ct = nf_ct_get(skb, &ctinfo);
843 	if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
844 		return 0;
845 
846 	if (family == NFPROTO_IPV4)
847 		err = tcf_ct_ipv4_is_fragment(skb, &frag);
848 	else
849 		err = tcf_ct_ipv6_is_fragment(skb, &frag);
850 	if (err || !frag)
851 		return err;
852 
853 	err = nf_ct_handle_fragments(net, skb, zone, family, &proto, &mru);
854 	if (err)
855 		return err;
856 
857 	*defrag = true;
858 	tc_skb_cb(skb)->mru = mru;
859 
860 	return 0;
861 }
862 
863 static void tcf_ct_params_free(struct tcf_ct_params *params)
864 {
865 	if (params->helper) {
866 #if IS_ENABLED(CONFIG_NF_NAT)
867 		if (params->ct_action & TCA_CT_ACT_NAT)
868 			nf_nat_helper_put(params->helper);
869 #endif
870 		nf_conntrack_helper_put(params->helper);
871 	}
872 	if (params->ct_ft)
873 		tcf_ct_flow_table_put(params->ct_ft);
874 	if (params->tmpl) {
875 		if (params->put_labels)
876 			nf_connlabels_put(nf_ct_net(params->tmpl));
877 
878 		nf_ct_put(params->tmpl);
879 	}
880 
881 	kfree(params);
882 }
883 
884 static void tcf_ct_params_free_rcu(struct rcu_head *head)
885 {
886 	struct tcf_ct_params *params;
887 
888 	params = container_of(head, struct tcf_ct_params, rcu);
889 	tcf_ct_params_free(params);
890 }
891 
892 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
893 {
894 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
895 	u32 new_mark;
896 
897 	if (!mask)
898 		return;
899 
900 	new_mark = mark | (READ_ONCE(ct->mark) & ~(mask));
901 	if (READ_ONCE(ct->mark) != new_mark) {
902 		WRITE_ONCE(ct->mark, new_mark);
903 		if (nf_ct_is_confirmed(ct))
904 			nf_conntrack_event_cache(IPCT_MARK, ct);
905 	}
906 #endif
907 }
908 
909 static void tcf_ct_act_set_labels(struct nf_conn *ct,
910 				  u32 *labels,
911 				  u32 *labels_m)
912 {
913 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
914 	size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
915 
916 	if (!memchr_inv(labels_m, 0, labels_sz))
917 		return;
918 
919 	nf_connlabels_replace(ct, labels, labels_m, 4);
920 #endif
921 }
922 
923 static int tcf_ct_act_nat(struct sk_buff *skb,
924 			  struct nf_conn *ct,
925 			  enum ip_conntrack_info ctinfo,
926 			  int ct_action,
927 			  struct nf_nat_range2 *range,
928 			  bool commit)
929 {
930 #if IS_ENABLED(CONFIG_NF_NAT)
931 	int err, action = 0;
932 
933 	if (!(ct_action & TCA_CT_ACT_NAT))
934 		return NF_ACCEPT;
935 	if (ct_action & TCA_CT_ACT_NAT_SRC)
936 		action |= BIT(NF_NAT_MANIP_SRC);
937 	if (ct_action & TCA_CT_ACT_NAT_DST)
938 		action |= BIT(NF_NAT_MANIP_DST);
939 
940 	err = nf_ct_nat(skb, ct, ctinfo, &action, range, commit);
941 
942 	if (action & BIT(NF_NAT_MANIP_SRC))
943 		tc_skb_cb(skb)->post_ct_snat = 1;
944 	if (action & BIT(NF_NAT_MANIP_DST))
945 		tc_skb_cb(skb)->post_ct_dnat = 1;
946 
947 	return err;
948 #else
949 	return NF_ACCEPT;
950 #endif
951 }
952 
953 TC_INDIRECT_SCOPE int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
954 				 struct tcf_result *res)
955 {
956 	struct net *net = dev_net(skb->dev);
957 	enum ip_conntrack_info ctinfo;
958 	struct tcf_ct *c = to_ct(a);
959 	struct nf_conn *tmpl = NULL;
960 	struct nf_hook_state state;
961 	bool cached, commit, clear;
962 	int nh_ofs, err, retval;
963 	struct tcf_ct_params *p;
964 	bool add_helper = false;
965 	bool skip_add = false;
966 	bool defrag = false;
967 	struct nf_conn *ct;
968 	u8 family;
969 
970 	p = rcu_dereference_bh(c->params);
971 
972 	retval = READ_ONCE(c->tcf_action);
973 	commit = p->ct_action & TCA_CT_ACT_COMMIT;
974 	clear = p->ct_action & TCA_CT_ACT_CLEAR;
975 	tmpl = p->tmpl;
976 
977 	tcf_lastuse_update(&c->tcf_tm);
978 	tcf_action_update_bstats(&c->common, skb);
979 
980 	if (clear) {
981 		tc_skb_cb(skb)->post_ct = false;
982 		ct = nf_ct_get(skb, &ctinfo);
983 		if (ct) {
984 			nf_ct_put(ct);
985 			nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
986 		}
987 
988 		goto out_clear;
989 	}
990 
991 	family = tcf_ct_skb_nf_family(skb);
992 	if (family == NFPROTO_UNSPEC)
993 		goto drop;
994 
995 	/* The conntrack module expects to be working at L3.
996 	 * We also try to pull the IPv4/6 header to linear area
997 	 */
998 	nh_ofs = skb_network_offset(skb);
999 	skb_pull_rcsum(skb, nh_ofs);
1000 	err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
1001 	if (err)
1002 		goto out_frag;
1003 
1004 	err = nf_ct_skb_network_trim(skb, family);
1005 	if (err)
1006 		goto drop;
1007 
1008 	/* If we are recirculating packets to match on ct fields and
1009 	 * committing with a separate ct action, then we don't need to
1010 	 * actually run the packet through conntrack twice unless it's for a
1011 	 * different zone.
1012 	 */
1013 	cached = tcf_ct_skb_nfct_cached(net, skb, p);
1014 	if (!cached) {
1015 		if (tcf_ct_flow_table_lookup(p, skb, family)) {
1016 			skip_add = true;
1017 			goto do_nat;
1018 		}
1019 
1020 		/* Associate skb with specified zone. */
1021 		if (tmpl) {
1022 			nf_conntrack_put(skb_nfct(skb));
1023 			nf_conntrack_get(&tmpl->ct_general);
1024 			nf_ct_set(skb, tmpl, IP_CT_NEW);
1025 		}
1026 
1027 		state.hook = NF_INET_PRE_ROUTING;
1028 		state.net = net;
1029 		state.pf = family;
1030 		err = nf_conntrack_in(skb, &state);
1031 		if (err != NF_ACCEPT)
1032 			goto out_push;
1033 	}
1034 
1035 do_nat:
1036 	ct = nf_ct_get(skb, &ctinfo);
1037 	if (!ct)
1038 		goto out_push;
1039 	nf_ct_deliver_cached_events(ct);
1040 	nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
1041 
1042 	err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1043 	if (err != NF_ACCEPT)
1044 		goto drop;
1045 
1046 	if (!nf_ct_is_confirmed(ct) && commit && p->helper && !nfct_help(ct)) {
1047 		err = __nf_ct_try_assign_helper(ct, p->tmpl, GFP_ATOMIC);
1048 		if (err)
1049 			goto drop;
1050 		add_helper = true;
1051 		if (p->ct_action & TCA_CT_ACT_NAT && !nfct_seqadj(ct)) {
1052 			if (!nfct_seqadj_ext_add(ct))
1053 				goto drop;
1054 		}
1055 	}
1056 
1057 	if (nf_ct_is_confirmed(ct) ? ((!cached && !skip_add) || add_helper) : commit) {
1058 		if (nf_ct_helper(skb, ct, ctinfo, family) != NF_ACCEPT)
1059 			goto drop;
1060 	}
1061 
1062 	if (commit) {
1063 		tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1064 		tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1065 
1066 		if (!nf_ct_is_confirmed(ct))
1067 			nf_conn_act_ct_ext_add(skb, ct, ctinfo);
1068 
1069 		/* This will take care of sending queued events
1070 		 * even if the connection is already confirmed.
1071 		 */
1072 		if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1073 			goto drop;
1074 	}
1075 
1076 	if (!skip_add)
1077 		tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1078 
1079 out_push:
1080 	skb_push_rcsum(skb, nh_ofs);
1081 
1082 	tc_skb_cb(skb)->post_ct = true;
1083 	tc_skb_cb(skb)->zone = p->zone;
1084 out_clear:
1085 	if (defrag)
1086 		qdisc_skb_cb(skb)->pkt_len = skb->len;
1087 	return retval;
1088 
1089 out_frag:
1090 	if (err != -EINPROGRESS)
1091 		tcf_action_inc_drop_qstats(&c->common);
1092 	return TC_ACT_CONSUMED;
1093 
1094 drop:
1095 	tcf_action_inc_drop_qstats(&c->common);
1096 	return TC_ACT_SHOT;
1097 }
1098 
1099 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1100 	[TCA_CT_ACTION] = { .type = NLA_U16 },
1101 	[TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)),
1102 	[TCA_CT_ZONE] = { .type = NLA_U16 },
1103 	[TCA_CT_MARK] = { .type = NLA_U32 },
1104 	[TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1105 	[TCA_CT_LABELS] = { .type = NLA_BINARY,
1106 			    .len = 128 / BITS_PER_BYTE },
1107 	[TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1108 				 .len = 128 / BITS_PER_BYTE },
1109 	[TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1110 	[TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1111 	[TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1112 	[TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1113 	[TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1114 	[TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1115 	[TCA_CT_HELPER_NAME] = { .type = NLA_STRING, .len = NF_CT_HELPER_NAME_LEN },
1116 	[TCA_CT_HELPER_FAMILY] = { .type = NLA_U8 },
1117 	[TCA_CT_HELPER_PROTO] = { .type = NLA_U8 },
1118 };
1119 
1120 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1121 				  struct tc_ct *parm,
1122 				  struct nlattr **tb,
1123 				  struct netlink_ext_ack *extack)
1124 {
1125 	struct nf_nat_range2 *range;
1126 
1127 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1128 		return 0;
1129 
1130 	if (!IS_ENABLED(CONFIG_NF_NAT)) {
1131 		NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1132 		return -EOPNOTSUPP;
1133 	}
1134 
1135 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1136 		return 0;
1137 
1138 	if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1139 	    (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1140 		NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1141 		return -EOPNOTSUPP;
1142 	}
1143 
1144 	range = &p->range;
1145 	if (tb[TCA_CT_NAT_IPV4_MIN]) {
1146 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1147 
1148 		p->ipv4_range = true;
1149 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1150 		range->min_addr.ip =
1151 			nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1152 
1153 		range->max_addr.ip = max_attr ?
1154 				     nla_get_in_addr(max_attr) :
1155 				     range->min_addr.ip;
1156 	} else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1157 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1158 
1159 		p->ipv4_range = false;
1160 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1161 		range->min_addr.in6 =
1162 			nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1163 
1164 		range->max_addr.in6 = max_attr ?
1165 				      nla_get_in6_addr(max_attr) :
1166 				      range->min_addr.in6;
1167 	}
1168 
1169 	if (tb[TCA_CT_NAT_PORT_MIN]) {
1170 		range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1171 		range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1172 
1173 		range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1174 				       nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1175 				       range->min_proto.all;
1176 	}
1177 
1178 	return 0;
1179 }
1180 
1181 static void tcf_ct_set_key_val(struct nlattr **tb,
1182 			       void *val, int val_type,
1183 			       void *mask, int mask_type,
1184 			       int len)
1185 {
1186 	if (!tb[val_type])
1187 		return;
1188 	nla_memcpy(val, tb[val_type], len);
1189 
1190 	if (!mask)
1191 		return;
1192 
1193 	if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1194 		memset(mask, 0xff, len);
1195 	else
1196 		nla_memcpy(mask, tb[mask_type], len);
1197 }
1198 
1199 static int tcf_ct_fill_params(struct net *net,
1200 			      struct tcf_ct_params *p,
1201 			      struct tc_ct *parm,
1202 			      struct nlattr **tb,
1203 			      struct netlink_ext_ack *extack)
1204 {
1205 	struct nf_conntrack_zone zone;
1206 	int err, family, proto, len;
1207 	bool put_labels = false;
1208 	struct nf_conn *tmpl;
1209 	char *name;
1210 
1211 	p->zone = NF_CT_DEFAULT_ZONE_ID;
1212 
1213 	tcf_ct_set_key_val(tb,
1214 			   &p->ct_action, TCA_CT_ACTION,
1215 			   NULL, TCA_CT_UNSPEC,
1216 			   sizeof(p->ct_action));
1217 
1218 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1219 		return 0;
1220 
1221 	err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1222 	if (err)
1223 		return err;
1224 
1225 	if (tb[TCA_CT_MARK]) {
1226 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1227 			NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1228 			return -EOPNOTSUPP;
1229 		}
1230 		tcf_ct_set_key_val(tb,
1231 				   &p->mark, TCA_CT_MARK,
1232 				   &p->mark_mask, TCA_CT_MARK_MASK,
1233 				   sizeof(p->mark));
1234 	}
1235 
1236 	if (tb[TCA_CT_LABELS]) {
1237 		unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1238 
1239 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1240 			NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1241 			return -EOPNOTSUPP;
1242 		}
1243 
1244 		if (nf_connlabels_get(net, n_bits - 1)) {
1245 			NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1246 			return -EOPNOTSUPP;
1247 		} else {
1248 			put_labels = true;
1249 		}
1250 
1251 		tcf_ct_set_key_val(tb,
1252 				   p->labels, TCA_CT_LABELS,
1253 				   p->labels_mask, TCA_CT_LABELS_MASK,
1254 				   sizeof(p->labels));
1255 	}
1256 
1257 	if (tb[TCA_CT_ZONE]) {
1258 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1259 			NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1260 			return -EOPNOTSUPP;
1261 		}
1262 
1263 		tcf_ct_set_key_val(tb,
1264 				   &p->zone, TCA_CT_ZONE,
1265 				   NULL, TCA_CT_UNSPEC,
1266 				   sizeof(p->zone));
1267 	}
1268 
1269 	nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1270 	tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1271 	if (!tmpl) {
1272 		NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1273 		return -ENOMEM;
1274 	}
1275 	p->tmpl = tmpl;
1276 	if (tb[TCA_CT_HELPER_NAME]) {
1277 		name = nla_data(tb[TCA_CT_HELPER_NAME]);
1278 		len = nla_len(tb[TCA_CT_HELPER_NAME]);
1279 		if (len > 16 || name[len - 1] != '\0') {
1280 			NL_SET_ERR_MSG_MOD(extack, "Failed to parse helper name.");
1281 			err = -EINVAL;
1282 			goto err;
1283 		}
1284 		family = tb[TCA_CT_HELPER_FAMILY] ? nla_get_u8(tb[TCA_CT_HELPER_FAMILY]) : AF_INET;
1285 		proto = tb[TCA_CT_HELPER_PROTO] ? nla_get_u8(tb[TCA_CT_HELPER_PROTO]) : IPPROTO_TCP;
1286 		err = nf_ct_add_helper(tmpl, name, family, proto,
1287 				       p->ct_action & TCA_CT_ACT_NAT, &p->helper);
1288 		if (err) {
1289 			NL_SET_ERR_MSG_MOD(extack, "Failed to add helper");
1290 			goto err;
1291 		}
1292 	}
1293 
1294 	p->put_labels = put_labels;
1295 
1296 	if (p->ct_action & TCA_CT_ACT_COMMIT)
1297 		__set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1298 	return 0;
1299 err:
1300 	if (put_labels)
1301 		nf_connlabels_put(net);
1302 
1303 	nf_ct_put(p->tmpl);
1304 	p->tmpl = NULL;
1305 	return err;
1306 }
1307 
1308 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1309 		       struct nlattr *est, struct tc_action **a,
1310 		       struct tcf_proto *tp, u32 flags,
1311 		       struct netlink_ext_ack *extack)
1312 {
1313 	struct tc_action_net *tn = net_generic(net, act_ct_ops.net_id);
1314 	bool bind = flags & TCA_ACT_FLAGS_BIND;
1315 	struct tcf_ct_params *params = NULL;
1316 	struct nlattr *tb[TCA_CT_MAX + 1];
1317 	struct tcf_chain *goto_ch = NULL;
1318 	struct tc_ct *parm;
1319 	struct tcf_ct *c;
1320 	int err, res = 0;
1321 	u32 index;
1322 
1323 	if (!nla) {
1324 		NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1325 		return -EINVAL;
1326 	}
1327 
1328 	err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1329 	if (err < 0)
1330 		return err;
1331 
1332 	if (!tb[TCA_CT_PARMS]) {
1333 		NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1334 		return -EINVAL;
1335 	}
1336 	parm = nla_data(tb[TCA_CT_PARMS]);
1337 	index = parm->index;
1338 	err = tcf_idr_check_alloc(tn, &index, a, bind);
1339 	if (err < 0)
1340 		return err;
1341 
1342 	if (!err) {
1343 		err = tcf_idr_create_from_flags(tn, index, est, a,
1344 						&act_ct_ops, bind, flags);
1345 		if (err) {
1346 			tcf_idr_cleanup(tn, index);
1347 			return err;
1348 		}
1349 		res = ACT_P_CREATED;
1350 	} else {
1351 		if (bind)
1352 			return ACT_P_BOUND;
1353 
1354 		if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
1355 			tcf_idr_release(*a, bind);
1356 			return -EEXIST;
1357 		}
1358 	}
1359 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1360 	if (err < 0)
1361 		goto cleanup;
1362 
1363 	c = to_ct(*a);
1364 
1365 	params = kzalloc(sizeof(*params), GFP_KERNEL);
1366 	if (unlikely(!params)) {
1367 		err = -ENOMEM;
1368 		goto cleanup;
1369 	}
1370 
1371 	err = tcf_ct_fill_params(net, params, parm, tb, extack);
1372 	if (err)
1373 		goto cleanup;
1374 
1375 	err = tcf_ct_flow_table_get(net, params);
1376 	if (err)
1377 		goto cleanup;
1378 
1379 	spin_lock_bh(&c->tcf_lock);
1380 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1381 	params = rcu_replace_pointer(c->params, params,
1382 				     lockdep_is_held(&c->tcf_lock));
1383 	spin_unlock_bh(&c->tcf_lock);
1384 
1385 	if (goto_ch)
1386 		tcf_chain_put_by_act(goto_ch);
1387 	if (params)
1388 		call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1389 
1390 	return res;
1391 
1392 cleanup:
1393 	if (goto_ch)
1394 		tcf_chain_put_by_act(goto_ch);
1395 	if (params)
1396 		tcf_ct_params_free(params);
1397 	tcf_idr_release(*a, bind);
1398 	return err;
1399 }
1400 
1401 static void tcf_ct_cleanup(struct tc_action *a)
1402 {
1403 	struct tcf_ct_params *params;
1404 	struct tcf_ct *c = to_ct(a);
1405 
1406 	params = rcu_dereference_protected(c->params, 1);
1407 	if (params)
1408 		call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1409 }
1410 
1411 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1412 			       void *val, int val_type,
1413 			       void *mask, int mask_type,
1414 			       int len)
1415 {
1416 	int err;
1417 
1418 	if (mask && !memchr_inv(mask, 0, len))
1419 		return 0;
1420 
1421 	err = nla_put(skb, val_type, len, val);
1422 	if (err)
1423 		return err;
1424 
1425 	if (mask_type != TCA_CT_UNSPEC) {
1426 		err = nla_put(skb, mask_type, len, mask);
1427 		if (err)
1428 			return err;
1429 	}
1430 
1431 	return 0;
1432 }
1433 
1434 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1435 {
1436 	struct nf_nat_range2 *range = &p->range;
1437 
1438 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1439 		return 0;
1440 
1441 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1442 		return 0;
1443 
1444 	if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1445 		if (p->ipv4_range) {
1446 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1447 					    range->min_addr.ip))
1448 				return -1;
1449 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1450 					    range->max_addr.ip))
1451 				return -1;
1452 		} else {
1453 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1454 					     &range->min_addr.in6))
1455 				return -1;
1456 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1457 					     &range->max_addr.in6))
1458 				return -1;
1459 		}
1460 	}
1461 
1462 	if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1463 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1464 				 range->min_proto.all))
1465 			return -1;
1466 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1467 				 range->max_proto.all))
1468 			return -1;
1469 	}
1470 
1471 	return 0;
1472 }
1473 
1474 static int tcf_ct_dump_helper(struct sk_buff *skb, struct nf_conntrack_helper *helper)
1475 {
1476 	if (!helper)
1477 		return 0;
1478 
1479 	if (nla_put_string(skb, TCA_CT_HELPER_NAME, helper->name) ||
1480 	    nla_put_u8(skb, TCA_CT_HELPER_FAMILY, helper->tuple.src.l3num) ||
1481 	    nla_put_u8(skb, TCA_CT_HELPER_PROTO, helper->tuple.dst.protonum))
1482 		return -1;
1483 
1484 	return 0;
1485 }
1486 
1487 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1488 			      int bind, int ref)
1489 {
1490 	unsigned char *b = skb_tail_pointer(skb);
1491 	struct tcf_ct *c = to_ct(a);
1492 	struct tcf_ct_params *p;
1493 
1494 	struct tc_ct opt = {
1495 		.index   = c->tcf_index,
1496 		.refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1497 		.bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1498 	};
1499 	struct tcf_t t;
1500 
1501 	spin_lock_bh(&c->tcf_lock);
1502 	p = rcu_dereference_protected(c->params,
1503 				      lockdep_is_held(&c->tcf_lock));
1504 	opt.action = c->tcf_action;
1505 
1506 	if (tcf_ct_dump_key_val(skb,
1507 				&p->ct_action, TCA_CT_ACTION,
1508 				NULL, TCA_CT_UNSPEC,
1509 				sizeof(p->ct_action)))
1510 		goto nla_put_failure;
1511 
1512 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1513 		goto skip_dump;
1514 
1515 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1516 	    tcf_ct_dump_key_val(skb,
1517 				&p->mark, TCA_CT_MARK,
1518 				&p->mark_mask, TCA_CT_MARK_MASK,
1519 				sizeof(p->mark)))
1520 		goto nla_put_failure;
1521 
1522 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1523 	    tcf_ct_dump_key_val(skb,
1524 				p->labels, TCA_CT_LABELS,
1525 				p->labels_mask, TCA_CT_LABELS_MASK,
1526 				sizeof(p->labels)))
1527 		goto nla_put_failure;
1528 
1529 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1530 	    tcf_ct_dump_key_val(skb,
1531 				&p->zone, TCA_CT_ZONE,
1532 				NULL, TCA_CT_UNSPEC,
1533 				sizeof(p->zone)))
1534 		goto nla_put_failure;
1535 
1536 	if (tcf_ct_dump_nat(skb, p))
1537 		goto nla_put_failure;
1538 
1539 	if (tcf_ct_dump_helper(skb, p->helper))
1540 		goto nla_put_failure;
1541 
1542 skip_dump:
1543 	if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1544 		goto nla_put_failure;
1545 
1546 	tcf_tm_dump(&t, &c->tcf_tm);
1547 	if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1548 		goto nla_put_failure;
1549 	spin_unlock_bh(&c->tcf_lock);
1550 
1551 	return skb->len;
1552 nla_put_failure:
1553 	spin_unlock_bh(&c->tcf_lock);
1554 	nlmsg_trim(skb, b);
1555 	return -1;
1556 }
1557 
1558 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1559 			     u64 drops, u64 lastuse, bool hw)
1560 {
1561 	struct tcf_ct *c = to_ct(a);
1562 
1563 	tcf_action_update_stats(a, bytes, packets, drops, hw);
1564 	c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1565 }
1566 
1567 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data,
1568 				    u32 *index_inc, bool bind,
1569 				    struct netlink_ext_ack *extack)
1570 {
1571 	if (bind) {
1572 		struct flow_action_entry *entry = entry_data;
1573 
1574 		if (tcf_ct_helper(act))
1575 			return -EOPNOTSUPP;
1576 
1577 		entry->id = FLOW_ACTION_CT;
1578 		entry->ct.action = tcf_ct_action(act);
1579 		entry->ct.zone = tcf_ct_zone(act);
1580 		entry->ct.flow_table = tcf_ct_ft(act);
1581 		*index_inc = 1;
1582 	} else {
1583 		struct flow_offload_action *fl_action = entry_data;
1584 
1585 		fl_action->id = FLOW_ACTION_CT;
1586 	}
1587 
1588 	return 0;
1589 }
1590 
1591 static struct tc_action_ops act_ct_ops = {
1592 	.kind		=	"ct",
1593 	.id		=	TCA_ID_CT,
1594 	.owner		=	THIS_MODULE,
1595 	.act		=	tcf_ct_act,
1596 	.dump		=	tcf_ct_dump,
1597 	.init		=	tcf_ct_init,
1598 	.cleanup	=	tcf_ct_cleanup,
1599 	.stats_update	=	tcf_stats_update,
1600 	.offload_act_setup =	tcf_ct_offload_act_setup,
1601 	.size		=	sizeof(struct tcf_ct),
1602 };
1603 MODULE_ALIAS_NET_ACT("ct");
1604 
1605 static __net_init int ct_init_net(struct net *net)
1606 {
1607 	struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1608 
1609 	return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1610 }
1611 
1612 static void __net_exit ct_exit_net(struct list_head *net_list)
1613 {
1614 	tc_action_net_exit(net_list, act_ct_ops.net_id);
1615 }
1616 
1617 static struct pernet_operations ct_net_ops = {
1618 	.init = ct_init_net,
1619 	.exit_batch = ct_exit_net,
1620 	.id   = &act_ct_ops.net_id,
1621 	.size = sizeof(struct tc_ct_action_net),
1622 };
1623 
1624 static int __init ct_init_module(void)
1625 {
1626 	int err;
1627 
1628 	act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1629 	if (!act_ct_wq)
1630 		return -ENOMEM;
1631 
1632 	err = tcf_ct_flow_tables_init();
1633 	if (err)
1634 		goto err_tbl_init;
1635 
1636 	err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1637 	if (err)
1638 		goto err_register;
1639 
1640 	static_branch_inc(&tcf_frag_xmit_count);
1641 
1642 	return 0;
1643 
1644 err_register:
1645 	tcf_ct_flow_tables_uninit();
1646 err_tbl_init:
1647 	destroy_workqueue(act_ct_wq);
1648 	return err;
1649 }
1650 
1651 static void __exit ct_cleanup_module(void)
1652 {
1653 	static_branch_dec(&tcf_frag_xmit_count);
1654 	tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1655 	tcf_ct_flow_tables_uninit();
1656 	destroy_workqueue(act_ct_wq);
1657 }
1658 
1659 module_init(ct_init_module);
1660 module_exit(ct_cleanup_module);
1661 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1662 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1663 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1664 MODULE_DESCRIPTION("Connection tracking action");
1665 MODULE_LICENSE("GPL v2");
1666