xref: /linux/net/sched/act_ct.c (revision f2527d8f566a45fa00ee5abd04d1c9476d4d704f)
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 					      struct flow_action *action)
174 {
175 	struct nf_conn_labels *ct_labels;
176 	struct flow_action_entry *entry;
177 	enum ip_conntrack_info ctinfo;
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 	ctinfo = dir == IP_CT_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
186 					     IP_CT_ESTABLISHED_REPLY;
187 	/* aligns with the CT reference on the SKB nf_ct_set */
188 	entry->ct_metadata.cookie = (unsigned long)ct | ctinfo;
189 	entry->ct_metadata.orig_dir = dir == IP_CT_DIR_ORIGINAL;
190 
191 	act_ct_labels = entry->ct_metadata.labels;
192 	ct_labels = nf_ct_labels_find(ct);
193 	if (ct_labels)
194 		memcpy(act_ct_labels, ct_labels->bits, NF_CT_LABELS_MAX_SIZE);
195 	else
196 		memset(act_ct_labels, 0, NF_CT_LABELS_MAX_SIZE);
197 }
198 
199 static int tcf_ct_flow_table_add_action_nat(struct net *net,
200 					    struct nf_conn *ct,
201 					    enum ip_conntrack_dir dir,
202 					    struct flow_action *action)
203 {
204 	const struct nf_conntrack_tuple *tuple = &ct->tuplehash[dir].tuple;
205 	struct nf_conntrack_tuple target;
206 
207 	if (!(ct->status & IPS_NAT_MASK))
208 		return 0;
209 
210 	nf_ct_invert_tuple(&target, &ct->tuplehash[!dir].tuple);
211 
212 	switch (tuple->src.l3num) {
213 	case NFPROTO_IPV4:
214 		tcf_ct_flow_table_add_action_nat_ipv4(tuple, target,
215 						      action);
216 		break;
217 	case NFPROTO_IPV6:
218 		tcf_ct_flow_table_add_action_nat_ipv6(tuple, target,
219 						      action);
220 		break;
221 	default:
222 		return -EOPNOTSUPP;
223 	}
224 
225 	switch (nf_ct_protonum(ct)) {
226 	case IPPROTO_TCP:
227 		tcf_ct_flow_table_add_action_nat_tcp(tuple, target, action);
228 		break;
229 	case IPPROTO_UDP:
230 		tcf_ct_flow_table_add_action_nat_udp(tuple, target, action);
231 		break;
232 	default:
233 		return -EOPNOTSUPP;
234 	}
235 
236 	return 0;
237 }
238 
239 static int tcf_ct_flow_table_fill_actions(struct net *net,
240 					  const struct flow_offload *flow,
241 					  enum flow_offload_tuple_dir tdir,
242 					  struct nf_flow_rule *flow_rule)
243 {
244 	struct flow_action *action = &flow_rule->rule->action;
245 	int num_entries = action->num_entries;
246 	struct nf_conn *ct = flow->ct;
247 	enum ip_conntrack_dir dir;
248 	int i, err;
249 
250 	switch (tdir) {
251 	case FLOW_OFFLOAD_DIR_ORIGINAL:
252 		dir = IP_CT_DIR_ORIGINAL;
253 		break;
254 	case FLOW_OFFLOAD_DIR_REPLY:
255 		dir = IP_CT_DIR_REPLY;
256 		break;
257 	default:
258 		return -EOPNOTSUPP;
259 	}
260 
261 	err = tcf_ct_flow_table_add_action_nat(net, ct, dir, action);
262 	if (err)
263 		goto err_nat;
264 
265 	tcf_ct_flow_table_add_action_meta(ct, dir, action);
266 	return 0;
267 
268 err_nat:
269 	/* Clear filled actions */
270 	for (i = num_entries; i < action->num_entries; i++)
271 		memset(&action->entries[i], 0, sizeof(action->entries[i]));
272 	action->num_entries = num_entries;
273 
274 	return err;
275 }
276 
277 static struct nf_flowtable_type flowtable_ct = {
278 	.action		= tcf_ct_flow_table_fill_actions,
279 	.owner		= THIS_MODULE,
280 };
281 
282 static int tcf_ct_flow_table_get(struct net *net, struct tcf_ct_params *params)
283 {
284 	struct tcf_ct_flow_table *ct_ft;
285 	int err = -ENOMEM;
286 
287 	mutex_lock(&zones_mutex);
288 	ct_ft = rhashtable_lookup_fast(&zones_ht, &params->zone, zones_params);
289 	if (ct_ft && refcount_inc_not_zero(&ct_ft->ref))
290 		goto out_unlock;
291 
292 	ct_ft = kzalloc(sizeof(*ct_ft), GFP_KERNEL);
293 	if (!ct_ft)
294 		goto err_alloc;
295 	refcount_set(&ct_ft->ref, 1);
296 
297 	ct_ft->zone = params->zone;
298 	err = rhashtable_insert_fast(&zones_ht, &ct_ft->node, zones_params);
299 	if (err)
300 		goto err_insert;
301 
302 	ct_ft->nf_ft.type = &flowtable_ct;
303 	ct_ft->nf_ft.flags |= NF_FLOWTABLE_HW_OFFLOAD |
304 			      NF_FLOWTABLE_COUNTER;
305 	err = nf_flow_table_init(&ct_ft->nf_ft);
306 	if (err)
307 		goto err_init;
308 	write_pnet(&ct_ft->nf_ft.net, net);
309 
310 	__module_get(THIS_MODULE);
311 out_unlock:
312 	params->ct_ft = ct_ft;
313 	params->nf_ft = &ct_ft->nf_ft;
314 	mutex_unlock(&zones_mutex);
315 
316 	return 0;
317 
318 err_init:
319 	rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
320 err_insert:
321 	kfree(ct_ft);
322 err_alloc:
323 	mutex_unlock(&zones_mutex);
324 	return err;
325 }
326 
327 static void tcf_ct_flow_table_cleanup_work(struct work_struct *work)
328 {
329 	struct flow_block_cb *block_cb, *tmp_cb;
330 	struct tcf_ct_flow_table *ct_ft;
331 	struct flow_block *block;
332 
333 	ct_ft = container_of(to_rcu_work(work), struct tcf_ct_flow_table,
334 			     rwork);
335 	nf_flow_table_free(&ct_ft->nf_ft);
336 
337 	/* Remove any remaining callbacks before cleanup */
338 	block = &ct_ft->nf_ft.flow_block;
339 	down_write(&ct_ft->nf_ft.flow_block_lock);
340 	list_for_each_entry_safe(block_cb, tmp_cb, &block->cb_list, list) {
341 		list_del(&block_cb->list);
342 		flow_block_cb_free(block_cb);
343 	}
344 	up_write(&ct_ft->nf_ft.flow_block_lock);
345 	kfree(ct_ft);
346 
347 	module_put(THIS_MODULE);
348 }
349 
350 static void tcf_ct_flow_table_put(struct tcf_ct_flow_table *ct_ft)
351 {
352 	if (refcount_dec_and_test(&ct_ft->ref)) {
353 		rhashtable_remove_fast(&zones_ht, &ct_ft->node, zones_params);
354 		INIT_RCU_WORK(&ct_ft->rwork, tcf_ct_flow_table_cleanup_work);
355 		queue_rcu_work(act_ct_wq, &ct_ft->rwork);
356 	}
357 }
358 
359 static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry,
360 				 struct nf_conn_act_ct_ext *act_ct_ext, u8 dir)
361 {
362 	entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC;
363 	entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir];
364 }
365 
366 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
367 				  struct nf_conn *ct,
368 				  bool tcp)
369 {
370 	struct nf_conn_act_ct_ext *act_ct_ext;
371 	struct flow_offload *entry;
372 	int err;
373 
374 	if (test_and_set_bit(IPS_OFFLOAD_BIT, &ct->status))
375 		return;
376 
377 	entry = flow_offload_alloc(ct);
378 	if (!entry) {
379 		WARN_ON_ONCE(1);
380 		goto err_alloc;
381 	}
382 
383 	if (tcp) {
384 		ct->proto.tcp.seen[0].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
385 		ct->proto.tcp.seen[1].flags |= IP_CT_TCP_FLAG_BE_LIBERAL;
386 	}
387 
388 	act_ct_ext = nf_conn_act_ct_ext_find(ct);
389 	if (act_ct_ext) {
390 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
391 		tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
392 	}
393 
394 	err = flow_offload_add(&ct_ft->nf_ft, entry);
395 	if (err)
396 		goto err_add;
397 
398 	return;
399 
400 err_add:
401 	flow_offload_free(entry);
402 err_alloc:
403 	clear_bit(IPS_OFFLOAD_BIT, &ct->status);
404 }
405 
406 static void tcf_ct_flow_table_process_conn(struct tcf_ct_flow_table *ct_ft,
407 					   struct nf_conn *ct,
408 					   enum ip_conntrack_info ctinfo)
409 {
410 	bool tcp = false;
411 
412 	if ((ctinfo != IP_CT_ESTABLISHED && ctinfo != IP_CT_ESTABLISHED_REPLY) ||
413 	    !test_bit(IPS_ASSURED_BIT, &ct->status))
414 		return;
415 
416 	switch (nf_ct_protonum(ct)) {
417 	case IPPROTO_TCP:
418 		tcp = true;
419 		if (ct->proto.tcp.state != TCP_CONNTRACK_ESTABLISHED)
420 			return;
421 		break;
422 	case IPPROTO_UDP:
423 		break;
424 #ifdef CONFIG_NF_CT_PROTO_GRE
425 	case IPPROTO_GRE: {
426 		struct nf_conntrack_tuple *tuple;
427 
428 		if (ct->status & IPS_NAT_MASK)
429 			return;
430 		tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
431 		/* No support for GRE v1 */
432 		if (tuple->src.u.gre.key || tuple->dst.u.gre.key)
433 			return;
434 		break;
435 	}
436 #endif
437 	default:
438 		return;
439 	}
440 
441 	if (nf_ct_ext_exist(ct, NF_CT_EXT_HELPER) ||
442 	    ct->status & IPS_SEQ_ADJUST)
443 		return;
444 
445 	tcf_ct_flow_table_add(ct_ft, ct, tcp);
446 }
447 
448 static bool
449 tcf_ct_flow_table_fill_tuple_ipv4(struct sk_buff *skb,
450 				  struct flow_offload_tuple *tuple,
451 				  struct tcphdr **tcph)
452 {
453 	struct flow_ports *ports;
454 	unsigned int thoff;
455 	struct iphdr *iph;
456 	size_t hdrsize;
457 	u8 ipproto;
458 
459 	if (!pskb_network_may_pull(skb, sizeof(*iph)))
460 		return false;
461 
462 	iph = ip_hdr(skb);
463 	thoff = iph->ihl * 4;
464 
465 	if (ip_is_fragment(iph) ||
466 	    unlikely(thoff != sizeof(struct iphdr)))
467 		return false;
468 
469 	ipproto = iph->protocol;
470 	switch (ipproto) {
471 	case IPPROTO_TCP:
472 		hdrsize = sizeof(struct tcphdr);
473 		break;
474 	case IPPROTO_UDP:
475 		hdrsize = sizeof(*ports);
476 		break;
477 #ifdef CONFIG_NF_CT_PROTO_GRE
478 	case IPPROTO_GRE:
479 		hdrsize = sizeof(struct gre_base_hdr);
480 		break;
481 #endif
482 	default:
483 		return false;
484 	}
485 
486 	if (iph->ttl <= 1)
487 		return false;
488 
489 	if (!pskb_network_may_pull(skb, thoff + hdrsize))
490 		return false;
491 
492 	switch (ipproto) {
493 	case IPPROTO_TCP:
494 		*tcph = (void *)(skb_network_header(skb) + thoff);
495 		fallthrough;
496 	case IPPROTO_UDP:
497 		ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
498 		tuple->src_port = ports->source;
499 		tuple->dst_port = ports->dest;
500 		break;
501 	case IPPROTO_GRE: {
502 		struct gre_base_hdr *greh;
503 
504 		greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
505 		if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
506 			return false;
507 		break;
508 	}
509 	}
510 
511 	iph = ip_hdr(skb);
512 
513 	tuple->src_v4.s_addr = iph->saddr;
514 	tuple->dst_v4.s_addr = iph->daddr;
515 	tuple->l3proto = AF_INET;
516 	tuple->l4proto = ipproto;
517 
518 	return true;
519 }
520 
521 static bool
522 tcf_ct_flow_table_fill_tuple_ipv6(struct sk_buff *skb,
523 				  struct flow_offload_tuple *tuple,
524 				  struct tcphdr **tcph)
525 {
526 	struct flow_ports *ports;
527 	struct ipv6hdr *ip6h;
528 	unsigned int thoff;
529 	size_t hdrsize;
530 	u8 nexthdr;
531 
532 	if (!pskb_network_may_pull(skb, sizeof(*ip6h)))
533 		return false;
534 
535 	ip6h = ipv6_hdr(skb);
536 	thoff = sizeof(*ip6h);
537 
538 	nexthdr = ip6h->nexthdr;
539 	switch (nexthdr) {
540 	case IPPROTO_TCP:
541 		hdrsize = sizeof(struct tcphdr);
542 		break;
543 	case IPPROTO_UDP:
544 		hdrsize = sizeof(*ports);
545 		break;
546 #ifdef CONFIG_NF_CT_PROTO_GRE
547 	case IPPROTO_GRE:
548 		hdrsize = sizeof(struct gre_base_hdr);
549 		break;
550 #endif
551 	default:
552 		return false;
553 	}
554 
555 	if (ip6h->hop_limit <= 1)
556 		return false;
557 
558 	if (!pskb_network_may_pull(skb, thoff + hdrsize))
559 		return false;
560 
561 	switch (nexthdr) {
562 	case IPPROTO_TCP:
563 		*tcph = (void *)(skb_network_header(skb) + thoff);
564 		fallthrough;
565 	case IPPROTO_UDP:
566 		ports = (struct flow_ports *)(skb_network_header(skb) + thoff);
567 		tuple->src_port = ports->source;
568 		tuple->dst_port = ports->dest;
569 		break;
570 	case IPPROTO_GRE: {
571 		struct gre_base_hdr *greh;
572 
573 		greh = (struct gre_base_hdr *)(skb_network_header(skb) + thoff);
574 		if ((greh->flags & GRE_VERSION) != GRE_VERSION_0)
575 			return false;
576 		break;
577 	}
578 	}
579 
580 	ip6h = ipv6_hdr(skb);
581 
582 	tuple->src_v6 = ip6h->saddr;
583 	tuple->dst_v6 = ip6h->daddr;
584 	tuple->l3proto = AF_INET6;
585 	tuple->l4proto = nexthdr;
586 
587 	return true;
588 }
589 
590 static bool tcf_ct_flow_table_lookup(struct tcf_ct_params *p,
591 				     struct sk_buff *skb,
592 				     u8 family)
593 {
594 	struct nf_flowtable *nf_ft = &p->ct_ft->nf_ft;
595 	struct flow_offload_tuple_rhash *tuplehash;
596 	struct flow_offload_tuple tuple = {};
597 	enum ip_conntrack_info ctinfo;
598 	struct tcphdr *tcph = NULL;
599 	struct flow_offload *flow;
600 	struct nf_conn *ct;
601 	u8 dir;
602 
603 	switch (family) {
604 	case NFPROTO_IPV4:
605 		if (!tcf_ct_flow_table_fill_tuple_ipv4(skb, &tuple, &tcph))
606 			return false;
607 		break;
608 	case NFPROTO_IPV6:
609 		if (!tcf_ct_flow_table_fill_tuple_ipv6(skb, &tuple, &tcph))
610 			return false;
611 		break;
612 	default:
613 		return false;
614 	}
615 
616 	tuplehash = flow_offload_lookup(nf_ft, &tuple);
617 	if (!tuplehash)
618 		return false;
619 
620 	dir = tuplehash->tuple.dir;
621 	flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
622 	ct = flow->ct;
623 
624 	if (tcph && (unlikely(tcph->fin || tcph->rst))) {
625 		flow_offload_teardown(flow);
626 		return false;
627 	}
628 
629 	ctinfo = dir == FLOW_OFFLOAD_DIR_ORIGINAL ? IP_CT_ESTABLISHED :
630 						    IP_CT_ESTABLISHED_REPLY;
631 
632 	flow_offload_refresh(nf_ft, flow);
633 	nf_conntrack_get(&ct->ct_general);
634 	nf_ct_set(skb, ct, ctinfo);
635 	if (nf_ft->flags & NF_FLOWTABLE_COUNTER)
636 		nf_ct_acct_update(ct, dir, skb->len);
637 
638 	return true;
639 }
640 
641 static int tcf_ct_flow_tables_init(void)
642 {
643 	return rhashtable_init(&zones_ht, &zones_params);
644 }
645 
646 static void tcf_ct_flow_tables_uninit(void)
647 {
648 	rhashtable_destroy(&zones_ht);
649 }
650 
651 static struct tc_action_ops act_ct_ops;
652 
653 struct tc_ct_action_net {
654 	struct tc_action_net tn; /* Must be first */
655 	bool labels;
656 };
657 
658 /* Determine whether skb->_nfct is equal to the result of conntrack lookup. */
659 static bool tcf_ct_skb_nfct_cached(struct net *net, struct sk_buff *skb,
660 				   struct tcf_ct_params *p)
661 {
662 	enum ip_conntrack_info ctinfo;
663 	struct nf_conn *ct;
664 
665 	ct = nf_ct_get(skb, &ctinfo);
666 	if (!ct)
667 		return false;
668 	if (!net_eq(net, read_pnet(&ct->ct_net)))
669 		goto drop_ct;
670 	if (nf_ct_zone(ct)->id != p->zone)
671 		goto drop_ct;
672 	if (p->helper) {
673 		struct nf_conn_help *help;
674 
675 		help = nf_ct_ext_find(ct, NF_CT_EXT_HELPER);
676 		if (help && rcu_access_pointer(help->helper) != p->helper)
677 			goto drop_ct;
678 	}
679 
680 	/* Force conntrack entry direction. */
681 	if ((p->ct_action & TCA_CT_ACT_FORCE) &&
682 	    CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL) {
683 		if (nf_ct_is_confirmed(ct))
684 			nf_ct_kill(ct);
685 
686 		goto drop_ct;
687 	}
688 
689 	return true;
690 
691 drop_ct:
692 	nf_ct_put(ct);
693 	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
694 
695 	return false;
696 }
697 
698 /* Trim the skb to the length specified by the IP/IPv6 header,
699  * removing any trailing lower-layer padding. This prepares the skb
700  * for higher-layer processing that assumes skb->len excludes padding
701  * (such as nf_ip_checksum). The caller needs to pull the skb to the
702  * network header, and ensure ip_hdr/ipv6_hdr points to valid data.
703  */
704 static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
705 {
706 	unsigned int len;
707 
708 	switch (family) {
709 	case NFPROTO_IPV4:
710 		len = ntohs(ip_hdr(skb)->tot_len);
711 		break;
712 	case NFPROTO_IPV6:
713 		len = sizeof(struct ipv6hdr)
714 			+ ntohs(ipv6_hdr(skb)->payload_len);
715 		break;
716 	default:
717 		len = skb->len;
718 	}
719 
720 	return pskb_trim_rcsum(skb, len);
721 }
722 
723 static u8 tcf_ct_skb_nf_family(struct sk_buff *skb)
724 {
725 	u8 family = NFPROTO_UNSPEC;
726 
727 	switch (skb_protocol(skb, true)) {
728 	case htons(ETH_P_IP):
729 		family = NFPROTO_IPV4;
730 		break;
731 	case htons(ETH_P_IPV6):
732 		family = NFPROTO_IPV6;
733 		break;
734 	default:
735 		break;
736 	}
737 
738 	return family;
739 }
740 
741 static int tcf_ct_ipv4_is_fragment(struct sk_buff *skb, bool *frag)
742 {
743 	unsigned int len;
744 
745 	len =  skb_network_offset(skb) + sizeof(struct iphdr);
746 	if (unlikely(skb->len < len))
747 		return -EINVAL;
748 	if (unlikely(!pskb_may_pull(skb, len)))
749 		return -ENOMEM;
750 
751 	*frag = ip_is_fragment(ip_hdr(skb));
752 	return 0;
753 }
754 
755 static int tcf_ct_ipv6_is_fragment(struct sk_buff *skb, bool *frag)
756 {
757 	unsigned int flags = 0, len, payload_ofs = 0;
758 	unsigned short frag_off;
759 	int nexthdr;
760 
761 	len =  skb_network_offset(skb) + sizeof(struct ipv6hdr);
762 	if (unlikely(skb->len < len))
763 		return -EINVAL;
764 	if (unlikely(!pskb_may_pull(skb, len)))
765 		return -ENOMEM;
766 
767 	nexthdr = ipv6_find_hdr(skb, &payload_ofs, -1, &frag_off, &flags);
768 	if (unlikely(nexthdr < 0))
769 		return -EPROTO;
770 
771 	*frag = flags & IP6_FH_F_FRAG;
772 	return 0;
773 }
774 
775 static int tcf_ct_handle_fragments(struct net *net, struct sk_buff *skb,
776 				   u8 family, u16 zone, bool *defrag)
777 {
778 	enum ip_conntrack_info ctinfo;
779 	struct nf_conn *ct;
780 	int err = 0;
781 	bool frag;
782 	u16 mru;
783 
784 	/* Previously seen (loopback)? Ignore. */
785 	ct = nf_ct_get(skb, &ctinfo);
786 	if ((ct && !nf_ct_is_template(ct)) || ctinfo == IP_CT_UNTRACKED)
787 		return 0;
788 
789 	if (family == NFPROTO_IPV4)
790 		err = tcf_ct_ipv4_is_fragment(skb, &frag);
791 	else
792 		err = tcf_ct_ipv6_is_fragment(skb, &frag);
793 	if (err || !frag)
794 		return err;
795 
796 	skb_get(skb);
797 	mru = tc_skb_cb(skb)->mru;
798 
799 	if (family == NFPROTO_IPV4) {
800 		enum ip_defrag_users user = IP_DEFRAG_CONNTRACK_IN + zone;
801 
802 		memset(IPCB(skb), 0, sizeof(struct inet_skb_parm));
803 		local_bh_disable();
804 		err = ip_defrag(net, skb, user);
805 		local_bh_enable();
806 		if (err && err != -EINPROGRESS)
807 			return err;
808 
809 		if (!err) {
810 			*defrag = true;
811 			mru = IPCB(skb)->frag_max_size;
812 		}
813 	} else { /* NFPROTO_IPV6 */
814 #if IS_ENABLED(CONFIG_NF_DEFRAG_IPV6)
815 		enum ip6_defrag_users user = IP6_DEFRAG_CONNTRACK_IN + zone;
816 
817 		memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
818 		err = nf_ct_frag6_gather(net, skb, user);
819 		if (err && err != -EINPROGRESS)
820 			goto out_free;
821 
822 		if (!err) {
823 			*defrag = true;
824 			mru = IP6CB(skb)->frag_max_size;
825 		}
826 #else
827 		err = -EOPNOTSUPP;
828 		goto out_free;
829 #endif
830 	}
831 
832 	if (err != -EINPROGRESS)
833 		tc_skb_cb(skb)->mru = mru;
834 	skb_clear_hash(skb);
835 	skb->ignore_df = 1;
836 	return err;
837 
838 out_free:
839 	kfree_skb(skb);
840 	return err;
841 }
842 
843 static void tcf_ct_params_free(struct tcf_ct_params *params)
844 {
845 	if (params->helper) {
846 #if IS_ENABLED(CONFIG_NF_NAT)
847 		if (params->ct_action & TCA_CT_ACT_NAT)
848 			nf_nat_helper_put(params->helper);
849 #endif
850 		nf_conntrack_helper_put(params->helper);
851 	}
852 	if (params->ct_ft)
853 		tcf_ct_flow_table_put(params->ct_ft);
854 	if (params->tmpl)
855 		nf_ct_put(params->tmpl);
856 	kfree(params);
857 }
858 
859 static void tcf_ct_params_free_rcu(struct rcu_head *head)
860 {
861 	struct tcf_ct_params *params;
862 
863 	params = container_of(head, struct tcf_ct_params, rcu);
864 	tcf_ct_params_free(params);
865 }
866 
867 static void tcf_ct_act_set_mark(struct nf_conn *ct, u32 mark, u32 mask)
868 {
869 #if IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)
870 	u32 new_mark;
871 
872 	if (!mask)
873 		return;
874 
875 	new_mark = mark | (READ_ONCE(ct->mark) & ~(mask));
876 	if (READ_ONCE(ct->mark) != new_mark) {
877 		WRITE_ONCE(ct->mark, new_mark);
878 		if (nf_ct_is_confirmed(ct))
879 			nf_conntrack_event_cache(IPCT_MARK, ct);
880 	}
881 #endif
882 }
883 
884 static void tcf_ct_act_set_labels(struct nf_conn *ct,
885 				  u32 *labels,
886 				  u32 *labels_m)
887 {
888 #if IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)
889 	size_t labels_sz = sizeof_field(struct tcf_ct_params, labels);
890 
891 	if (!memchr_inv(labels_m, 0, labels_sz))
892 		return;
893 
894 	nf_connlabels_replace(ct, labels, labels_m, 4);
895 #endif
896 }
897 
898 static int tcf_ct_act_nat(struct sk_buff *skb,
899 			  struct nf_conn *ct,
900 			  enum ip_conntrack_info ctinfo,
901 			  int ct_action,
902 			  struct nf_nat_range2 *range,
903 			  bool commit)
904 {
905 #if IS_ENABLED(CONFIG_NF_NAT)
906 	int err, action = 0;
907 
908 	if (!(ct_action & TCA_CT_ACT_NAT))
909 		return NF_ACCEPT;
910 	if (ct_action & TCA_CT_ACT_NAT_SRC)
911 		action |= BIT(NF_NAT_MANIP_SRC);
912 	if (ct_action & TCA_CT_ACT_NAT_DST)
913 		action |= BIT(NF_NAT_MANIP_DST);
914 
915 	err = nf_ct_nat(skb, ct, ctinfo, &action, range, commit);
916 
917 	if (action & BIT(NF_NAT_MANIP_SRC))
918 		tc_skb_cb(skb)->post_ct_snat = 1;
919 	if (action & BIT(NF_NAT_MANIP_DST))
920 		tc_skb_cb(skb)->post_ct_dnat = 1;
921 
922 	return err;
923 #else
924 	return NF_ACCEPT;
925 #endif
926 }
927 
928 TC_INDIRECT_SCOPE int tcf_ct_act(struct sk_buff *skb, const struct tc_action *a,
929 				 struct tcf_result *res)
930 {
931 	struct net *net = dev_net(skb->dev);
932 	enum ip_conntrack_info ctinfo;
933 	struct tcf_ct *c = to_ct(a);
934 	struct nf_conn *tmpl = NULL;
935 	struct nf_hook_state state;
936 	bool cached, commit, clear;
937 	int nh_ofs, err, retval;
938 	struct tcf_ct_params *p;
939 	bool add_helper = false;
940 	bool skip_add = false;
941 	bool defrag = false;
942 	struct nf_conn *ct;
943 	u8 family;
944 
945 	p = rcu_dereference_bh(c->params);
946 
947 	retval = READ_ONCE(c->tcf_action);
948 	commit = p->ct_action & TCA_CT_ACT_COMMIT;
949 	clear = p->ct_action & TCA_CT_ACT_CLEAR;
950 	tmpl = p->tmpl;
951 
952 	tcf_lastuse_update(&c->tcf_tm);
953 	tcf_action_update_bstats(&c->common, skb);
954 
955 	if (clear) {
956 		tc_skb_cb(skb)->post_ct = false;
957 		ct = nf_ct_get(skb, &ctinfo);
958 		if (ct) {
959 			nf_ct_put(ct);
960 			nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
961 		}
962 
963 		goto out_clear;
964 	}
965 
966 	family = tcf_ct_skb_nf_family(skb);
967 	if (family == NFPROTO_UNSPEC)
968 		goto drop;
969 
970 	/* The conntrack module expects to be working at L3.
971 	 * We also try to pull the IPv4/6 header to linear area
972 	 */
973 	nh_ofs = skb_network_offset(skb);
974 	skb_pull_rcsum(skb, nh_ofs);
975 	err = tcf_ct_handle_fragments(net, skb, family, p->zone, &defrag);
976 	if (err == -EINPROGRESS) {
977 		retval = TC_ACT_STOLEN;
978 		goto out_clear;
979 	}
980 	if (err)
981 		goto drop;
982 
983 	err = tcf_ct_skb_network_trim(skb, family);
984 	if (err)
985 		goto drop;
986 
987 	/* If we are recirculating packets to match on ct fields and
988 	 * committing with a separate ct action, then we don't need to
989 	 * actually run the packet through conntrack twice unless it's for a
990 	 * different zone.
991 	 */
992 	cached = tcf_ct_skb_nfct_cached(net, skb, p);
993 	if (!cached) {
994 		if (tcf_ct_flow_table_lookup(p, skb, family)) {
995 			skip_add = true;
996 			goto do_nat;
997 		}
998 
999 		/* Associate skb with specified zone. */
1000 		if (tmpl) {
1001 			nf_conntrack_put(skb_nfct(skb));
1002 			nf_conntrack_get(&tmpl->ct_general);
1003 			nf_ct_set(skb, tmpl, IP_CT_NEW);
1004 		}
1005 
1006 		state.hook = NF_INET_PRE_ROUTING;
1007 		state.net = net;
1008 		state.pf = family;
1009 		err = nf_conntrack_in(skb, &state);
1010 		if (err != NF_ACCEPT)
1011 			goto out_push;
1012 	}
1013 
1014 do_nat:
1015 	ct = nf_ct_get(skb, &ctinfo);
1016 	if (!ct)
1017 		goto out_push;
1018 	nf_ct_deliver_cached_events(ct);
1019 	nf_conn_act_ct_ext_fill(skb, ct, ctinfo);
1020 
1021 	err = tcf_ct_act_nat(skb, ct, ctinfo, p->ct_action, &p->range, commit);
1022 	if (err != NF_ACCEPT)
1023 		goto drop;
1024 
1025 	if (!nf_ct_is_confirmed(ct) && commit && p->helper && !nfct_help(ct)) {
1026 		err = __nf_ct_try_assign_helper(ct, p->tmpl, GFP_ATOMIC);
1027 		if (err)
1028 			goto drop;
1029 		add_helper = true;
1030 		if (p->ct_action & TCA_CT_ACT_NAT && !nfct_seqadj(ct)) {
1031 			if (!nfct_seqadj_ext_add(ct))
1032 				goto drop;
1033 		}
1034 	}
1035 
1036 	if (nf_ct_is_confirmed(ct) ? ((!cached && !skip_add) || add_helper) : commit) {
1037 		if (nf_ct_helper(skb, ct, ctinfo, family) != NF_ACCEPT)
1038 			goto drop;
1039 	}
1040 
1041 	if (commit) {
1042 		tcf_ct_act_set_mark(ct, p->mark, p->mark_mask);
1043 		tcf_ct_act_set_labels(ct, p->labels, p->labels_mask);
1044 
1045 		if (!nf_ct_is_confirmed(ct))
1046 			nf_conn_act_ct_ext_add(ct);
1047 
1048 		/* This will take care of sending queued events
1049 		 * even if the connection is already confirmed.
1050 		 */
1051 		if (nf_conntrack_confirm(skb) != NF_ACCEPT)
1052 			goto drop;
1053 	}
1054 
1055 	if (!skip_add)
1056 		tcf_ct_flow_table_process_conn(p->ct_ft, ct, ctinfo);
1057 
1058 out_push:
1059 	skb_push_rcsum(skb, nh_ofs);
1060 
1061 	tc_skb_cb(skb)->post_ct = true;
1062 	tc_skb_cb(skb)->zone = p->zone;
1063 out_clear:
1064 	if (defrag)
1065 		qdisc_skb_cb(skb)->pkt_len = skb->len;
1066 	return retval;
1067 
1068 drop:
1069 	tcf_action_inc_drop_qstats(&c->common);
1070 	return TC_ACT_SHOT;
1071 }
1072 
1073 static const struct nla_policy ct_policy[TCA_CT_MAX + 1] = {
1074 	[TCA_CT_ACTION] = { .type = NLA_U16 },
1075 	[TCA_CT_PARMS] = NLA_POLICY_EXACT_LEN(sizeof(struct tc_ct)),
1076 	[TCA_CT_ZONE] = { .type = NLA_U16 },
1077 	[TCA_CT_MARK] = { .type = NLA_U32 },
1078 	[TCA_CT_MARK_MASK] = { .type = NLA_U32 },
1079 	[TCA_CT_LABELS] = { .type = NLA_BINARY,
1080 			    .len = 128 / BITS_PER_BYTE },
1081 	[TCA_CT_LABELS_MASK] = { .type = NLA_BINARY,
1082 				 .len = 128 / BITS_PER_BYTE },
1083 	[TCA_CT_NAT_IPV4_MIN] = { .type = NLA_U32 },
1084 	[TCA_CT_NAT_IPV4_MAX] = { .type = NLA_U32 },
1085 	[TCA_CT_NAT_IPV6_MIN] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1086 	[TCA_CT_NAT_IPV6_MAX] = NLA_POLICY_EXACT_LEN(sizeof(struct in6_addr)),
1087 	[TCA_CT_NAT_PORT_MIN] = { .type = NLA_U16 },
1088 	[TCA_CT_NAT_PORT_MAX] = { .type = NLA_U16 },
1089 	[TCA_CT_HELPER_NAME] = { .type = NLA_STRING, .len = NF_CT_HELPER_NAME_LEN },
1090 	[TCA_CT_HELPER_FAMILY] = { .type = NLA_U8 },
1091 	[TCA_CT_HELPER_PROTO] = { .type = NLA_U8 },
1092 };
1093 
1094 static int tcf_ct_fill_params_nat(struct tcf_ct_params *p,
1095 				  struct tc_ct *parm,
1096 				  struct nlattr **tb,
1097 				  struct netlink_ext_ack *extack)
1098 {
1099 	struct nf_nat_range2 *range;
1100 
1101 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1102 		return 0;
1103 
1104 	if (!IS_ENABLED(CONFIG_NF_NAT)) {
1105 		NL_SET_ERR_MSG_MOD(extack, "Netfilter nat isn't enabled in kernel");
1106 		return -EOPNOTSUPP;
1107 	}
1108 
1109 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1110 		return 0;
1111 
1112 	if ((p->ct_action & TCA_CT_ACT_NAT_SRC) &&
1113 	    (p->ct_action & TCA_CT_ACT_NAT_DST)) {
1114 		NL_SET_ERR_MSG_MOD(extack, "dnat and snat can't be enabled at the same time");
1115 		return -EOPNOTSUPP;
1116 	}
1117 
1118 	range = &p->range;
1119 	if (tb[TCA_CT_NAT_IPV4_MIN]) {
1120 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV4_MAX];
1121 
1122 		p->ipv4_range = true;
1123 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1124 		range->min_addr.ip =
1125 			nla_get_in_addr(tb[TCA_CT_NAT_IPV4_MIN]);
1126 
1127 		range->max_addr.ip = max_attr ?
1128 				     nla_get_in_addr(max_attr) :
1129 				     range->min_addr.ip;
1130 	} else if (tb[TCA_CT_NAT_IPV6_MIN]) {
1131 		struct nlattr *max_attr = tb[TCA_CT_NAT_IPV6_MAX];
1132 
1133 		p->ipv4_range = false;
1134 		range->flags |= NF_NAT_RANGE_MAP_IPS;
1135 		range->min_addr.in6 =
1136 			nla_get_in6_addr(tb[TCA_CT_NAT_IPV6_MIN]);
1137 
1138 		range->max_addr.in6 = max_attr ?
1139 				      nla_get_in6_addr(max_attr) :
1140 				      range->min_addr.in6;
1141 	}
1142 
1143 	if (tb[TCA_CT_NAT_PORT_MIN]) {
1144 		range->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
1145 		range->min_proto.all = nla_get_be16(tb[TCA_CT_NAT_PORT_MIN]);
1146 
1147 		range->max_proto.all = tb[TCA_CT_NAT_PORT_MAX] ?
1148 				       nla_get_be16(tb[TCA_CT_NAT_PORT_MAX]) :
1149 				       range->min_proto.all;
1150 	}
1151 
1152 	return 0;
1153 }
1154 
1155 static void tcf_ct_set_key_val(struct nlattr **tb,
1156 			       void *val, int val_type,
1157 			       void *mask, int mask_type,
1158 			       int len)
1159 {
1160 	if (!tb[val_type])
1161 		return;
1162 	nla_memcpy(val, tb[val_type], len);
1163 
1164 	if (!mask)
1165 		return;
1166 
1167 	if (mask_type == TCA_CT_UNSPEC || !tb[mask_type])
1168 		memset(mask, 0xff, len);
1169 	else
1170 		nla_memcpy(mask, tb[mask_type], len);
1171 }
1172 
1173 static int tcf_ct_fill_params(struct net *net,
1174 			      struct tcf_ct_params *p,
1175 			      struct tc_ct *parm,
1176 			      struct nlattr **tb,
1177 			      struct netlink_ext_ack *extack)
1178 {
1179 	struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1180 	struct nf_conntrack_zone zone;
1181 	int err, family, proto, len;
1182 	struct nf_conn *tmpl;
1183 	char *name;
1184 
1185 	p->zone = NF_CT_DEFAULT_ZONE_ID;
1186 
1187 	tcf_ct_set_key_val(tb,
1188 			   &p->ct_action, TCA_CT_ACTION,
1189 			   NULL, TCA_CT_UNSPEC,
1190 			   sizeof(p->ct_action));
1191 
1192 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1193 		return 0;
1194 
1195 	err = tcf_ct_fill_params_nat(p, parm, tb, extack);
1196 	if (err)
1197 		return err;
1198 
1199 	if (tb[TCA_CT_MARK]) {
1200 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_MARK)) {
1201 			NL_SET_ERR_MSG_MOD(extack, "Conntrack mark isn't enabled.");
1202 			return -EOPNOTSUPP;
1203 		}
1204 		tcf_ct_set_key_val(tb,
1205 				   &p->mark, TCA_CT_MARK,
1206 				   &p->mark_mask, TCA_CT_MARK_MASK,
1207 				   sizeof(p->mark));
1208 	}
1209 
1210 	if (tb[TCA_CT_LABELS]) {
1211 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS)) {
1212 			NL_SET_ERR_MSG_MOD(extack, "Conntrack labels isn't enabled.");
1213 			return -EOPNOTSUPP;
1214 		}
1215 
1216 		if (!tn->labels) {
1217 			NL_SET_ERR_MSG_MOD(extack, "Failed to set connlabel length");
1218 			return -EOPNOTSUPP;
1219 		}
1220 		tcf_ct_set_key_val(tb,
1221 				   p->labels, TCA_CT_LABELS,
1222 				   p->labels_mask, TCA_CT_LABELS_MASK,
1223 				   sizeof(p->labels));
1224 	}
1225 
1226 	if (tb[TCA_CT_ZONE]) {
1227 		if (!IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES)) {
1228 			NL_SET_ERR_MSG_MOD(extack, "Conntrack zones isn't enabled.");
1229 			return -EOPNOTSUPP;
1230 		}
1231 
1232 		tcf_ct_set_key_val(tb,
1233 				   &p->zone, TCA_CT_ZONE,
1234 				   NULL, TCA_CT_UNSPEC,
1235 				   sizeof(p->zone));
1236 	}
1237 
1238 	nf_ct_zone_init(&zone, p->zone, NF_CT_DEFAULT_ZONE_DIR, 0);
1239 	tmpl = nf_ct_tmpl_alloc(net, &zone, GFP_KERNEL);
1240 	if (!tmpl) {
1241 		NL_SET_ERR_MSG_MOD(extack, "Failed to allocate conntrack template");
1242 		return -ENOMEM;
1243 	}
1244 	p->tmpl = tmpl;
1245 	if (tb[TCA_CT_HELPER_NAME]) {
1246 		name = nla_data(tb[TCA_CT_HELPER_NAME]);
1247 		len = nla_len(tb[TCA_CT_HELPER_NAME]);
1248 		if (len > 16 || name[len - 1] != '\0') {
1249 			NL_SET_ERR_MSG_MOD(extack, "Failed to parse helper name.");
1250 			err = -EINVAL;
1251 			goto err;
1252 		}
1253 		family = tb[TCA_CT_HELPER_FAMILY] ? nla_get_u8(tb[TCA_CT_HELPER_FAMILY]) : AF_INET;
1254 		proto = tb[TCA_CT_HELPER_PROTO] ? nla_get_u8(tb[TCA_CT_HELPER_PROTO]) : IPPROTO_TCP;
1255 		err = nf_ct_add_helper(tmpl, name, family, proto,
1256 				       p->ct_action & TCA_CT_ACT_NAT, &p->helper);
1257 		if (err) {
1258 			NL_SET_ERR_MSG_MOD(extack, "Failed to add helper");
1259 			goto err;
1260 		}
1261 	}
1262 
1263 	__set_bit(IPS_CONFIRMED_BIT, &tmpl->status);
1264 	return 0;
1265 err:
1266 	nf_ct_put(p->tmpl);
1267 	p->tmpl = NULL;
1268 	return err;
1269 }
1270 
1271 static int tcf_ct_init(struct net *net, struct nlattr *nla,
1272 		       struct nlattr *est, struct tc_action **a,
1273 		       struct tcf_proto *tp, u32 flags,
1274 		       struct netlink_ext_ack *extack)
1275 {
1276 	struct tc_action_net *tn = net_generic(net, act_ct_ops.net_id);
1277 	bool bind = flags & TCA_ACT_FLAGS_BIND;
1278 	struct tcf_ct_params *params = NULL;
1279 	struct nlattr *tb[TCA_CT_MAX + 1];
1280 	struct tcf_chain *goto_ch = NULL;
1281 	struct tc_ct *parm;
1282 	struct tcf_ct *c;
1283 	int err, res = 0;
1284 	u32 index;
1285 
1286 	if (!nla) {
1287 		NL_SET_ERR_MSG_MOD(extack, "Ct requires attributes to be passed");
1288 		return -EINVAL;
1289 	}
1290 
1291 	err = nla_parse_nested(tb, TCA_CT_MAX, nla, ct_policy, extack);
1292 	if (err < 0)
1293 		return err;
1294 
1295 	if (!tb[TCA_CT_PARMS]) {
1296 		NL_SET_ERR_MSG_MOD(extack, "Missing required ct parameters");
1297 		return -EINVAL;
1298 	}
1299 	parm = nla_data(tb[TCA_CT_PARMS]);
1300 	index = parm->index;
1301 	err = tcf_idr_check_alloc(tn, &index, a, bind);
1302 	if (err < 0)
1303 		return err;
1304 
1305 	if (!err) {
1306 		err = tcf_idr_create_from_flags(tn, index, est, a,
1307 						&act_ct_ops, bind, flags);
1308 		if (err) {
1309 			tcf_idr_cleanup(tn, index);
1310 			return err;
1311 		}
1312 		res = ACT_P_CREATED;
1313 	} else {
1314 		if (bind)
1315 			return 0;
1316 
1317 		if (!(flags & TCA_ACT_FLAGS_REPLACE)) {
1318 			tcf_idr_release(*a, bind);
1319 			return -EEXIST;
1320 		}
1321 	}
1322 	err = tcf_action_check_ctrlact(parm->action, tp, &goto_ch, extack);
1323 	if (err < 0)
1324 		goto cleanup;
1325 
1326 	c = to_ct(*a);
1327 
1328 	params = kzalloc(sizeof(*params), GFP_KERNEL);
1329 	if (unlikely(!params)) {
1330 		err = -ENOMEM;
1331 		goto cleanup;
1332 	}
1333 
1334 	err = tcf_ct_fill_params(net, params, parm, tb, extack);
1335 	if (err)
1336 		goto cleanup;
1337 
1338 	err = tcf_ct_flow_table_get(net, params);
1339 	if (err)
1340 		goto cleanup;
1341 
1342 	spin_lock_bh(&c->tcf_lock);
1343 	goto_ch = tcf_action_set_ctrlact(*a, parm->action, goto_ch);
1344 	params = rcu_replace_pointer(c->params, params,
1345 				     lockdep_is_held(&c->tcf_lock));
1346 	spin_unlock_bh(&c->tcf_lock);
1347 
1348 	if (goto_ch)
1349 		tcf_chain_put_by_act(goto_ch);
1350 	if (params)
1351 		call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1352 
1353 	return res;
1354 
1355 cleanup:
1356 	if (goto_ch)
1357 		tcf_chain_put_by_act(goto_ch);
1358 	if (params)
1359 		tcf_ct_params_free(params);
1360 	tcf_idr_release(*a, bind);
1361 	return err;
1362 }
1363 
1364 static void tcf_ct_cleanup(struct tc_action *a)
1365 {
1366 	struct tcf_ct_params *params;
1367 	struct tcf_ct *c = to_ct(a);
1368 
1369 	params = rcu_dereference_protected(c->params, 1);
1370 	if (params)
1371 		call_rcu(&params->rcu, tcf_ct_params_free_rcu);
1372 }
1373 
1374 static int tcf_ct_dump_key_val(struct sk_buff *skb,
1375 			       void *val, int val_type,
1376 			       void *mask, int mask_type,
1377 			       int len)
1378 {
1379 	int err;
1380 
1381 	if (mask && !memchr_inv(mask, 0, len))
1382 		return 0;
1383 
1384 	err = nla_put(skb, val_type, len, val);
1385 	if (err)
1386 		return err;
1387 
1388 	if (mask_type != TCA_CT_UNSPEC) {
1389 		err = nla_put(skb, mask_type, len, mask);
1390 		if (err)
1391 			return err;
1392 	}
1393 
1394 	return 0;
1395 }
1396 
1397 static int tcf_ct_dump_nat(struct sk_buff *skb, struct tcf_ct_params *p)
1398 {
1399 	struct nf_nat_range2 *range = &p->range;
1400 
1401 	if (!(p->ct_action & TCA_CT_ACT_NAT))
1402 		return 0;
1403 
1404 	if (!(p->ct_action & (TCA_CT_ACT_NAT_SRC | TCA_CT_ACT_NAT_DST)))
1405 		return 0;
1406 
1407 	if (range->flags & NF_NAT_RANGE_MAP_IPS) {
1408 		if (p->ipv4_range) {
1409 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MIN,
1410 					    range->min_addr.ip))
1411 				return -1;
1412 			if (nla_put_in_addr(skb, TCA_CT_NAT_IPV4_MAX,
1413 					    range->max_addr.ip))
1414 				return -1;
1415 		} else {
1416 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MIN,
1417 					     &range->min_addr.in6))
1418 				return -1;
1419 			if (nla_put_in6_addr(skb, TCA_CT_NAT_IPV6_MAX,
1420 					     &range->max_addr.in6))
1421 				return -1;
1422 		}
1423 	}
1424 
1425 	if (range->flags & NF_NAT_RANGE_PROTO_SPECIFIED) {
1426 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MIN,
1427 				 range->min_proto.all))
1428 			return -1;
1429 		if (nla_put_be16(skb, TCA_CT_NAT_PORT_MAX,
1430 				 range->max_proto.all))
1431 			return -1;
1432 	}
1433 
1434 	return 0;
1435 }
1436 
1437 static int tcf_ct_dump_helper(struct sk_buff *skb, struct nf_conntrack_helper *helper)
1438 {
1439 	if (!helper)
1440 		return 0;
1441 
1442 	if (nla_put_string(skb, TCA_CT_HELPER_NAME, helper->name) ||
1443 	    nla_put_u8(skb, TCA_CT_HELPER_FAMILY, helper->tuple.src.l3num) ||
1444 	    nla_put_u8(skb, TCA_CT_HELPER_PROTO, helper->tuple.dst.protonum))
1445 		return -1;
1446 
1447 	return 0;
1448 }
1449 
1450 static inline int tcf_ct_dump(struct sk_buff *skb, struct tc_action *a,
1451 			      int bind, int ref)
1452 {
1453 	unsigned char *b = skb_tail_pointer(skb);
1454 	struct tcf_ct *c = to_ct(a);
1455 	struct tcf_ct_params *p;
1456 
1457 	struct tc_ct opt = {
1458 		.index   = c->tcf_index,
1459 		.refcnt  = refcount_read(&c->tcf_refcnt) - ref,
1460 		.bindcnt = atomic_read(&c->tcf_bindcnt) - bind,
1461 	};
1462 	struct tcf_t t;
1463 
1464 	spin_lock_bh(&c->tcf_lock);
1465 	p = rcu_dereference_protected(c->params,
1466 				      lockdep_is_held(&c->tcf_lock));
1467 	opt.action = c->tcf_action;
1468 
1469 	if (tcf_ct_dump_key_val(skb,
1470 				&p->ct_action, TCA_CT_ACTION,
1471 				NULL, TCA_CT_UNSPEC,
1472 				sizeof(p->ct_action)))
1473 		goto nla_put_failure;
1474 
1475 	if (p->ct_action & TCA_CT_ACT_CLEAR)
1476 		goto skip_dump;
1477 
1478 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_MARK) &&
1479 	    tcf_ct_dump_key_val(skb,
1480 				&p->mark, TCA_CT_MARK,
1481 				&p->mark_mask, TCA_CT_MARK_MASK,
1482 				sizeof(p->mark)))
1483 		goto nla_put_failure;
1484 
1485 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_LABELS) &&
1486 	    tcf_ct_dump_key_val(skb,
1487 				p->labels, TCA_CT_LABELS,
1488 				p->labels_mask, TCA_CT_LABELS_MASK,
1489 				sizeof(p->labels)))
1490 		goto nla_put_failure;
1491 
1492 	if (IS_ENABLED(CONFIG_NF_CONNTRACK_ZONES) &&
1493 	    tcf_ct_dump_key_val(skb,
1494 				&p->zone, TCA_CT_ZONE,
1495 				NULL, TCA_CT_UNSPEC,
1496 				sizeof(p->zone)))
1497 		goto nla_put_failure;
1498 
1499 	if (tcf_ct_dump_nat(skb, p))
1500 		goto nla_put_failure;
1501 
1502 	if (tcf_ct_dump_helper(skb, p->helper))
1503 		goto nla_put_failure;
1504 
1505 skip_dump:
1506 	if (nla_put(skb, TCA_CT_PARMS, sizeof(opt), &opt))
1507 		goto nla_put_failure;
1508 
1509 	tcf_tm_dump(&t, &c->tcf_tm);
1510 	if (nla_put_64bit(skb, TCA_CT_TM, sizeof(t), &t, TCA_CT_PAD))
1511 		goto nla_put_failure;
1512 	spin_unlock_bh(&c->tcf_lock);
1513 
1514 	return skb->len;
1515 nla_put_failure:
1516 	spin_unlock_bh(&c->tcf_lock);
1517 	nlmsg_trim(skb, b);
1518 	return -1;
1519 }
1520 
1521 static void tcf_stats_update(struct tc_action *a, u64 bytes, u64 packets,
1522 			     u64 drops, u64 lastuse, bool hw)
1523 {
1524 	struct tcf_ct *c = to_ct(a);
1525 
1526 	tcf_action_update_stats(a, bytes, packets, drops, hw);
1527 	c->tcf_tm.lastuse = max_t(u64, c->tcf_tm.lastuse, lastuse);
1528 }
1529 
1530 static int tcf_ct_offload_act_setup(struct tc_action *act, void *entry_data,
1531 				    u32 *index_inc, bool bind,
1532 				    struct netlink_ext_ack *extack)
1533 {
1534 	if (bind) {
1535 		struct flow_action_entry *entry = entry_data;
1536 
1537 		entry->id = FLOW_ACTION_CT;
1538 		entry->ct.action = tcf_ct_action(act);
1539 		entry->ct.zone = tcf_ct_zone(act);
1540 		entry->ct.flow_table = tcf_ct_ft(act);
1541 		*index_inc = 1;
1542 	} else {
1543 		struct flow_offload_action *fl_action = entry_data;
1544 
1545 		fl_action->id = FLOW_ACTION_CT;
1546 	}
1547 
1548 	return 0;
1549 }
1550 
1551 static struct tc_action_ops act_ct_ops = {
1552 	.kind		=	"ct",
1553 	.id		=	TCA_ID_CT,
1554 	.owner		=	THIS_MODULE,
1555 	.act		=	tcf_ct_act,
1556 	.dump		=	tcf_ct_dump,
1557 	.init		=	tcf_ct_init,
1558 	.cleanup	=	tcf_ct_cleanup,
1559 	.stats_update	=	tcf_stats_update,
1560 	.offload_act_setup =	tcf_ct_offload_act_setup,
1561 	.size		=	sizeof(struct tcf_ct),
1562 };
1563 
1564 static __net_init int ct_init_net(struct net *net)
1565 {
1566 	unsigned int n_bits = sizeof_field(struct tcf_ct_params, labels) * 8;
1567 	struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1568 
1569 	if (nf_connlabels_get(net, n_bits - 1)) {
1570 		tn->labels = false;
1571 		pr_err("act_ct: Failed to set connlabels length");
1572 	} else {
1573 		tn->labels = true;
1574 	}
1575 
1576 	return tc_action_net_init(net, &tn->tn, &act_ct_ops);
1577 }
1578 
1579 static void __net_exit ct_exit_net(struct list_head *net_list)
1580 {
1581 	struct net *net;
1582 
1583 	rtnl_lock();
1584 	list_for_each_entry(net, net_list, exit_list) {
1585 		struct tc_ct_action_net *tn = net_generic(net, act_ct_ops.net_id);
1586 
1587 		if (tn->labels)
1588 			nf_connlabels_put(net);
1589 	}
1590 	rtnl_unlock();
1591 
1592 	tc_action_net_exit(net_list, act_ct_ops.net_id);
1593 }
1594 
1595 static struct pernet_operations ct_net_ops = {
1596 	.init = ct_init_net,
1597 	.exit_batch = ct_exit_net,
1598 	.id   = &act_ct_ops.net_id,
1599 	.size = sizeof(struct tc_ct_action_net),
1600 };
1601 
1602 static int __init ct_init_module(void)
1603 {
1604 	int err;
1605 
1606 	act_ct_wq = alloc_ordered_workqueue("act_ct_workqueue", 0);
1607 	if (!act_ct_wq)
1608 		return -ENOMEM;
1609 
1610 	err = tcf_ct_flow_tables_init();
1611 	if (err)
1612 		goto err_tbl_init;
1613 
1614 	err = tcf_register_action(&act_ct_ops, &ct_net_ops);
1615 	if (err)
1616 		goto err_register;
1617 
1618 	static_branch_inc(&tcf_frag_xmit_count);
1619 
1620 	return 0;
1621 
1622 err_register:
1623 	tcf_ct_flow_tables_uninit();
1624 err_tbl_init:
1625 	destroy_workqueue(act_ct_wq);
1626 	return err;
1627 }
1628 
1629 static void __exit ct_cleanup_module(void)
1630 {
1631 	static_branch_dec(&tcf_frag_xmit_count);
1632 	tcf_unregister_action(&act_ct_ops, &ct_net_ops);
1633 	tcf_ct_flow_tables_uninit();
1634 	destroy_workqueue(act_ct_wq);
1635 }
1636 
1637 module_init(ct_init_module);
1638 module_exit(ct_cleanup_module);
1639 MODULE_AUTHOR("Paul Blakey <paulb@mellanox.com>");
1640 MODULE_AUTHOR("Yossi Kuperman <yossiku@mellanox.com>");
1641 MODULE_AUTHOR("Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>");
1642 MODULE_DESCRIPTION("Connection tracking action");
1643 MODULE_LICENSE("GPL v2");
1644