1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/kernel.h>
3 #include <linux/init.h>
4 #include <linux/module.h>
5 #include <linux/netfilter.h>
6 #include <linux/rhashtable.h>
7 #include <linux/netdevice.h>
8 #include <net/ip.h>
9 #include <net/ip6_route.h>
10 #include <net/netfilter/nf_tables.h>
11 #include <net/netfilter/nf_flow_table.h>
12 #include <net/netfilter/nf_conntrack.h>
13 #include <net/netfilter/nf_conntrack_core.h>
14 #include <net/netfilter/nf_conntrack_l4proto.h>
15 #include <net/netfilter/nf_conntrack_tuple.h>
16 
17 static DEFINE_MUTEX(flowtable_lock);
18 static LIST_HEAD(flowtables);
19 
20 static void
21 flow_offload_fill_dir(struct flow_offload *flow,
22 		      enum flow_offload_tuple_dir dir)
23 {
24 	struct flow_offload_tuple *ft = &flow->tuplehash[dir].tuple;
25 	struct nf_conntrack_tuple *ctt = &flow->ct->tuplehash[dir].tuple;
26 
27 	ft->dir = dir;
28 
29 	switch (ctt->src.l3num) {
30 	case NFPROTO_IPV4:
31 		ft->src_v4 = ctt->src.u3.in;
32 		ft->dst_v4 = ctt->dst.u3.in;
33 		break;
34 	case NFPROTO_IPV6:
35 		ft->src_v6 = ctt->src.u3.in6;
36 		ft->dst_v6 = ctt->dst.u3.in6;
37 		break;
38 	}
39 
40 	ft->l3proto = ctt->src.l3num;
41 	ft->l4proto = ctt->dst.protonum;
42 
43 	switch (ctt->dst.protonum) {
44 	case IPPROTO_TCP:
45 	case IPPROTO_UDP:
46 		ft->src_port = ctt->src.u.tcp.port;
47 		ft->dst_port = ctt->dst.u.tcp.port;
48 		break;
49 	}
50 }
51 
52 struct flow_offload *flow_offload_alloc(struct nf_conn *ct)
53 {
54 	struct flow_offload *flow;
55 
56 	if (unlikely(nf_ct_is_dying(ct)))
57 		return NULL;
58 
59 	flow = kzalloc(sizeof(*flow), GFP_ATOMIC);
60 	if (!flow)
61 		return NULL;
62 
63 	refcount_inc(&ct->ct_general.use);
64 	flow->ct = ct;
65 
66 	flow_offload_fill_dir(flow, FLOW_OFFLOAD_DIR_ORIGINAL);
67 	flow_offload_fill_dir(flow, FLOW_OFFLOAD_DIR_REPLY);
68 
69 	if (ct->status & IPS_SRC_NAT)
70 		__set_bit(NF_FLOW_SNAT, &flow->flags);
71 	if (ct->status & IPS_DST_NAT)
72 		__set_bit(NF_FLOW_DNAT, &flow->flags);
73 
74 	return flow;
75 }
76 EXPORT_SYMBOL_GPL(flow_offload_alloc);
77 
78 static u32 flow_offload_dst_cookie(struct flow_offload_tuple *flow_tuple)
79 {
80 	const struct rt6_info *rt;
81 
82 	if (flow_tuple->l3proto == NFPROTO_IPV6) {
83 		rt = (const struct rt6_info *)flow_tuple->dst_cache;
84 		return rt6_get_cookie(rt);
85 	}
86 
87 	return 0;
88 }
89 
90 static int flow_offload_fill_route(struct flow_offload *flow,
91 				   const struct nf_flow_route *route,
92 				   enum flow_offload_tuple_dir dir)
93 {
94 	struct flow_offload_tuple *flow_tuple = &flow->tuplehash[dir].tuple;
95 	struct dst_entry *dst = route->tuple[dir].dst;
96 	int i, j = 0;
97 
98 	switch (flow_tuple->l3proto) {
99 	case NFPROTO_IPV4:
100 		flow_tuple->mtu = ip_dst_mtu_maybe_forward(dst, true);
101 		break;
102 	case NFPROTO_IPV6:
103 		flow_tuple->mtu = ip6_dst_mtu_maybe_forward(dst, true);
104 		break;
105 	}
106 
107 	flow_tuple->iifidx = route->tuple[dir].in.ifindex;
108 	for (i = route->tuple[dir].in.num_encaps - 1; i >= 0; i--) {
109 		flow_tuple->encap[j].id = route->tuple[dir].in.encap[i].id;
110 		flow_tuple->encap[j].proto = route->tuple[dir].in.encap[i].proto;
111 		if (route->tuple[dir].in.ingress_vlans & BIT(i))
112 			flow_tuple->in_vlan_ingress |= BIT(j);
113 		j++;
114 	}
115 	flow_tuple->encap_num = route->tuple[dir].in.num_encaps;
116 
117 	switch (route->tuple[dir].xmit_type) {
118 	case FLOW_OFFLOAD_XMIT_DIRECT:
119 		memcpy(flow_tuple->out.h_dest, route->tuple[dir].out.h_dest,
120 		       ETH_ALEN);
121 		memcpy(flow_tuple->out.h_source, route->tuple[dir].out.h_source,
122 		       ETH_ALEN);
123 		flow_tuple->out.ifidx = route->tuple[dir].out.ifindex;
124 		flow_tuple->out.hw_ifidx = route->tuple[dir].out.hw_ifindex;
125 		break;
126 	case FLOW_OFFLOAD_XMIT_XFRM:
127 	case FLOW_OFFLOAD_XMIT_NEIGH:
128 		flow_tuple->dst_cache = dst;
129 		flow_tuple->dst_cookie = flow_offload_dst_cookie(flow_tuple);
130 		break;
131 	default:
132 		WARN_ON_ONCE(1);
133 		break;
134 	}
135 	flow_tuple->xmit_type = route->tuple[dir].xmit_type;
136 
137 	return 0;
138 }
139 
140 static void nft_flow_dst_release(struct flow_offload *flow,
141 				 enum flow_offload_tuple_dir dir)
142 {
143 	if (flow->tuplehash[dir].tuple.xmit_type == FLOW_OFFLOAD_XMIT_NEIGH ||
144 	    flow->tuplehash[dir].tuple.xmit_type == FLOW_OFFLOAD_XMIT_XFRM)
145 		dst_release(flow->tuplehash[dir].tuple.dst_cache);
146 }
147 
148 void flow_offload_route_init(struct flow_offload *flow,
149 			    const struct nf_flow_route *route)
150 {
151 	flow_offload_fill_route(flow, route, FLOW_OFFLOAD_DIR_ORIGINAL);
152 	flow_offload_fill_route(flow, route, FLOW_OFFLOAD_DIR_REPLY);
153 	flow->type = NF_FLOW_OFFLOAD_ROUTE;
154 }
155 EXPORT_SYMBOL_GPL(flow_offload_route_init);
156 
157 static void flow_offload_fixup_tcp(struct ip_ct_tcp *tcp)
158 {
159 	tcp->seen[0].td_maxwin = 0;
160 	tcp->seen[1].td_maxwin = 0;
161 }
162 
163 static void flow_offload_fixup_ct(struct nf_conn *ct)
164 {
165 	struct net *net = nf_ct_net(ct);
166 	int l4num = nf_ct_protonum(ct);
167 	s32 timeout;
168 
169 	if (l4num == IPPROTO_TCP) {
170 		struct nf_tcp_net *tn = nf_tcp_pernet(net);
171 
172 		flow_offload_fixup_tcp(&ct->proto.tcp);
173 
174 		timeout = tn->timeouts[ct->proto.tcp.state];
175 		timeout -= tn->offload_timeout;
176 	} else if (l4num == IPPROTO_UDP) {
177 		struct nf_udp_net *tn = nf_udp_pernet(net);
178 		enum udp_conntrack state =
179 			test_bit(IPS_SEEN_REPLY_BIT, &ct->status) ?
180 			UDP_CT_REPLIED : UDP_CT_UNREPLIED;
181 
182 		timeout = tn->timeouts[state];
183 		timeout -= tn->offload_timeout;
184 	} else {
185 		return;
186 	}
187 
188 	if (timeout < 0)
189 		timeout = 0;
190 
191 	if (nf_flow_timeout_delta(READ_ONCE(ct->timeout)) > (__s32)timeout)
192 		WRITE_ONCE(ct->timeout, nfct_time_stamp + timeout);
193 }
194 
195 static void flow_offload_route_release(struct flow_offload *flow)
196 {
197 	nft_flow_dst_release(flow, FLOW_OFFLOAD_DIR_ORIGINAL);
198 	nft_flow_dst_release(flow, FLOW_OFFLOAD_DIR_REPLY);
199 }
200 
201 void flow_offload_free(struct flow_offload *flow)
202 {
203 	switch (flow->type) {
204 	case NF_FLOW_OFFLOAD_ROUTE:
205 		flow_offload_route_release(flow);
206 		break;
207 	default:
208 		break;
209 	}
210 	nf_ct_put(flow->ct);
211 	kfree_rcu(flow, rcu_head);
212 }
213 EXPORT_SYMBOL_GPL(flow_offload_free);
214 
215 static u32 flow_offload_hash(const void *data, u32 len, u32 seed)
216 {
217 	const struct flow_offload_tuple *tuple = data;
218 
219 	return jhash(tuple, offsetof(struct flow_offload_tuple, __hash), seed);
220 }
221 
222 static u32 flow_offload_hash_obj(const void *data, u32 len, u32 seed)
223 {
224 	const struct flow_offload_tuple_rhash *tuplehash = data;
225 
226 	return jhash(&tuplehash->tuple, offsetof(struct flow_offload_tuple, __hash), seed);
227 }
228 
229 static int flow_offload_hash_cmp(struct rhashtable_compare_arg *arg,
230 					const void *ptr)
231 {
232 	const struct flow_offload_tuple *tuple = arg->key;
233 	const struct flow_offload_tuple_rhash *x = ptr;
234 
235 	if (memcmp(&x->tuple, tuple, offsetof(struct flow_offload_tuple, __hash)))
236 		return 1;
237 
238 	return 0;
239 }
240 
241 static const struct rhashtable_params nf_flow_offload_rhash_params = {
242 	.head_offset		= offsetof(struct flow_offload_tuple_rhash, node),
243 	.hashfn			= flow_offload_hash,
244 	.obj_hashfn		= flow_offload_hash_obj,
245 	.obj_cmpfn		= flow_offload_hash_cmp,
246 	.automatic_shrinking	= true,
247 };
248 
249 unsigned long flow_offload_get_timeout(struct flow_offload *flow)
250 {
251 	unsigned long timeout = NF_FLOW_TIMEOUT;
252 	struct net *net = nf_ct_net(flow->ct);
253 	int l4num = nf_ct_protonum(flow->ct);
254 
255 	if (l4num == IPPROTO_TCP) {
256 		struct nf_tcp_net *tn = nf_tcp_pernet(net);
257 
258 		timeout = tn->offload_timeout;
259 	} else if (l4num == IPPROTO_UDP) {
260 		struct nf_udp_net *tn = nf_udp_pernet(net);
261 
262 		timeout = tn->offload_timeout;
263 	}
264 
265 	return timeout;
266 }
267 
268 int flow_offload_add(struct nf_flowtable *flow_table, struct flow_offload *flow)
269 {
270 	int err;
271 
272 	flow->timeout = nf_flowtable_time_stamp + flow_offload_get_timeout(flow);
273 
274 	err = rhashtable_insert_fast(&flow_table->rhashtable,
275 				     &flow->tuplehash[0].node,
276 				     nf_flow_offload_rhash_params);
277 	if (err < 0)
278 		return err;
279 
280 	err = rhashtable_insert_fast(&flow_table->rhashtable,
281 				     &flow->tuplehash[1].node,
282 				     nf_flow_offload_rhash_params);
283 	if (err < 0) {
284 		rhashtable_remove_fast(&flow_table->rhashtable,
285 				       &flow->tuplehash[0].node,
286 				       nf_flow_offload_rhash_params);
287 		return err;
288 	}
289 
290 	nf_ct_offload_timeout(flow->ct);
291 
292 	if (nf_flowtable_hw_offload(flow_table)) {
293 		__set_bit(NF_FLOW_HW, &flow->flags);
294 		nf_flow_offload_add(flow_table, flow);
295 	}
296 
297 	return 0;
298 }
299 EXPORT_SYMBOL_GPL(flow_offload_add);
300 
301 void flow_offload_refresh(struct nf_flowtable *flow_table,
302 			  struct flow_offload *flow, bool force)
303 {
304 	u32 timeout;
305 
306 	timeout = nf_flowtable_time_stamp + flow_offload_get_timeout(flow);
307 	if (force || timeout - READ_ONCE(flow->timeout) > HZ)
308 		WRITE_ONCE(flow->timeout, timeout);
309 	else
310 		return;
311 
312 	if (likely(!nf_flowtable_hw_offload(flow_table)))
313 		return;
314 
315 	nf_flow_offload_add(flow_table, flow);
316 }
317 EXPORT_SYMBOL_GPL(flow_offload_refresh);
318 
319 static bool nf_flow_is_outdated(const struct flow_offload *flow)
320 {
321 	return test_bit(IPS_SEEN_REPLY_BIT, &flow->ct->status) &&
322 		!test_bit(NF_FLOW_HW_ESTABLISHED, &flow->flags);
323 }
324 
325 static inline bool nf_flow_has_expired(const struct flow_offload *flow)
326 {
327 	return nf_flow_timeout_delta(flow->timeout) <= 0;
328 }
329 
330 static void flow_offload_del(struct nf_flowtable *flow_table,
331 			     struct flow_offload *flow)
332 {
333 	rhashtable_remove_fast(&flow_table->rhashtable,
334 			       &flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].node,
335 			       nf_flow_offload_rhash_params);
336 	rhashtable_remove_fast(&flow_table->rhashtable,
337 			       &flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].node,
338 			       nf_flow_offload_rhash_params);
339 	flow_offload_free(flow);
340 }
341 
342 void flow_offload_teardown(struct flow_offload *flow)
343 {
344 	clear_bit(IPS_OFFLOAD_BIT, &flow->ct->status);
345 	set_bit(NF_FLOW_TEARDOWN, &flow->flags);
346 	flow_offload_fixup_ct(flow->ct);
347 }
348 EXPORT_SYMBOL_GPL(flow_offload_teardown);
349 
350 struct flow_offload_tuple_rhash *
351 flow_offload_lookup(struct nf_flowtable *flow_table,
352 		    struct flow_offload_tuple *tuple)
353 {
354 	struct flow_offload_tuple_rhash *tuplehash;
355 	struct flow_offload *flow;
356 	int dir;
357 
358 	tuplehash = rhashtable_lookup(&flow_table->rhashtable, tuple,
359 				      nf_flow_offload_rhash_params);
360 	if (!tuplehash)
361 		return NULL;
362 
363 	dir = tuplehash->tuple.dir;
364 	flow = container_of(tuplehash, struct flow_offload, tuplehash[dir]);
365 	if (test_bit(NF_FLOW_TEARDOWN, &flow->flags))
366 		return NULL;
367 
368 	if (unlikely(nf_ct_is_dying(flow->ct)))
369 		return NULL;
370 
371 	return tuplehash;
372 }
373 EXPORT_SYMBOL_GPL(flow_offload_lookup);
374 
375 static int
376 nf_flow_table_iterate(struct nf_flowtable *flow_table,
377 		      void (*iter)(struct nf_flowtable *flowtable,
378 				   struct flow_offload *flow, void *data),
379 		      void *data)
380 {
381 	struct flow_offload_tuple_rhash *tuplehash;
382 	struct rhashtable_iter hti;
383 	struct flow_offload *flow;
384 	int err = 0;
385 
386 	rhashtable_walk_enter(&flow_table->rhashtable, &hti);
387 	rhashtable_walk_start(&hti);
388 
389 	while ((tuplehash = rhashtable_walk_next(&hti))) {
390 		if (IS_ERR(tuplehash)) {
391 			if (PTR_ERR(tuplehash) != -EAGAIN) {
392 				err = PTR_ERR(tuplehash);
393 				break;
394 			}
395 			continue;
396 		}
397 		if (tuplehash->tuple.dir)
398 			continue;
399 
400 		flow = container_of(tuplehash, struct flow_offload, tuplehash[0]);
401 
402 		iter(flow_table, flow, data);
403 	}
404 	rhashtable_walk_stop(&hti);
405 	rhashtable_walk_exit(&hti);
406 
407 	return err;
408 }
409 
410 static void nf_flow_offload_gc_step(struct nf_flowtable *flow_table,
411 				    struct flow_offload *flow, void *data)
412 {
413 	if (nf_flow_has_expired(flow) ||
414 	    nf_ct_is_dying(flow->ct) ||
415 	    nf_flow_is_outdated(flow))
416 		flow_offload_teardown(flow);
417 
418 	if (test_bit(NF_FLOW_TEARDOWN, &flow->flags)) {
419 		if (test_bit(NF_FLOW_HW, &flow->flags)) {
420 			if (!test_bit(NF_FLOW_HW_DYING, &flow->flags))
421 				nf_flow_offload_del(flow_table, flow);
422 			else if (test_bit(NF_FLOW_HW_DEAD, &flow->flags))
423 				flow_offload_del(flow_table, flow);
424 		} else {
425 			flow_offload_del(flow_table, flow);
426 		}
427 	} else if (test_bit(NF_FLOW_HW, &flow->flags)) {
428 		nf_flow_offload_stats(flow_table, flow);
429 	}
430 }
431 
432 void nf_flow_table_gc_run(struct nf_flowtable *flow_table)
433 {
434 	nf_flow_table_iterate(flow_table, nf_flow_offload_gc_step, NULL);
435 }
436 
437 static void nf_flow_offload_work_gc(struct work_struct *work)
438 {
439 	struct nf_flowtable *flow_table;
440 
441 	flow_table = container_of(work, struct nf_flowtable, gc_work.work);
442 	nf_flow_table_gc_run(flow_table);
443 	queue_delayed_work(system_power_efficient_wq, &flow_table->gc_work, HZ);
444 }
445 
446 static void nf_flow_nat_port_tcp(struct sk_buff *skb, unsigned int thoff,
447 				 __be16 port, __be16 new_port)
448 {
449 	struct tcphdr *tcph;
450 
451 	tcph = (void *)(skb_network_header(skb) + thoff);
452 	inet_proto_csum_replace2(&tcph->check, skb, port, new_port, false);
453 }
454 
455 static void nf_flow_nat_port_udp(struct sk_buff *skb, unsigned int thoff,
456 				 __be16 port, __be16 new_port)
457 {
458 	struct udphdr *udph;
459 
460 	udph = (void *)(skb_network_header(skb) + thoff);
461 	if (udph->check || skb->ip_summed == CHECKSUM_PARTIAL) {
462 		inet_proto_csum_replace2(&udph->check, skb, port,
463 					 new_port, false);
464 		if (!udph->check)
465 			udph->check = CSUM_MANGLED_0;
466 	}
467 }
468 
469 static void nf_flow_nat_port(struct sk_buff *skb, unsigned int thoff,
470 			     u8 protocol, __be16 port, __be16 new_port)
471 {
472 	switch (protocol) {
473 	case IPPROTO_TCP:
474 		nf_flow_nat_port_tcp(skb, thoff, port, new_port);
475 		break;
476 	case IPPROTO_UDP:
477 		nf_flow_nat_port_udp(skb, thoff, port, new_port);
478 		break;
479 	}
480 }
481 
482 void nf_flow_snat_port(const struct flow_offload *flow,
483 		       struct sk_buff *skb, unsigned int thoff,
484 		       u8 protocol, enum flow_offload_tuple_dir dir)
485 {
486 	struct flow_ports *hdr;
487 	__be16 port, new_port;
488 
489 	hdr = (void *)(skb_network_header(skb) + thoff);
490 
491 	switch (dir) {
492 	case FLOW_OFFLOAD_DIR_ORIGINAL:
493 		port = hdr->source;
494 		new_port = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_port;
495 		hdr->source = new_port;
496 		break;
497 	case FLOW_OFFLOAD_DIR_REPLY:
498 		port = hdr->dest;
499 		new_port = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_port;
500 		hdr->dest = new_port;
501 		break;
502 	}
503 
504 	nf_flow_nat_port(skb, thoff, protocol, port, new_port);
505 }
506 EXPORT_SYMBOL_GPL(nf_flow_snat_port);
507 
508 void nf_flow_dnat_port(const struct flow_offload *flow, struct sk_buff *skb,
509 		       unsigned int thoff, u8 protocol,
510 		       enum flow_offload_tuple_dir dir)
511 {
512 	struct flow_ports *hdr;
513 	__be16 port, new_port;
514 
515 	hdr = (void *)(skb_network_header(skb) + thoff);
516 
517 	switch (dir) {
518 	case FLOW_OFFLOAD_DIR_ORIGINAL:
519 		port = hdr->dest;
520 		new_port = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_port;
521 		hdr->dest = new_port;
522 		break;
523 	case FLOW_OFFLOAD_DIR_REPLY:
524 		port = hdr->source;
525 		new_port = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_port;
526 		hdr->source = new_port;
527 		break;
528 	}
529 
530 	nf_flow_nat_port(skb, thoff, protocol, port, new_port);
531 }
532 EXPORT_SYMBOL_GPL(nf_flow_dnat_port);
533 
534 int nf_flow_table_init(struct nf_flowtable *flowtable)
535 {
536 	int err;
537 
538 	INIT_DELAYED_WORK(&flowtable->gc_work, nf_flow_offload_work_gc);
539 	flow_block_init(&flowtable->flow_block);
540 	init_rwsem(&flowtable->flow_block_lock);
541 
542 	err = rhashtable_init(&flowtable->rhashtable,
543 			      &nf_flow_offload_rhash_params);
544 	if (err < 0)
545 		return err;
546 
547 	queue_delayed_work(system_power_efficient_wq,
548 			   &flowtable->gc_work, HZ);
549 
550 	mutex_lock(&flowtable_lock);
551 	list_add(&flowtable->list, &flowtables);
552 	mutex_unlock(&flowtable_lock);
553 
554 	return 0;
555 }
556 EXPORT_SYMBOL_GPL(nf_flow_table_init);
557 
558 static void nf_flow_table_do_cleanup(struct nf_flowtable *flow_table,
559 				     struct flow_offload *flow, void *data)
560 {
561 	struct net_device *dev = data;
562 
563 	if (!dev) {
564 		flow_offload_teardown(flow);
565 		return;
566 	}
567 
568 	if (net_eq(nf_ct_net(flow->ct), dev_net(dev)) &&
569 	    (flow->tuplehash[0].tuple.iifidx == dev->ifindex ||
570 	     flow->tuplehash[1].tuple.iifidx == dev->ifindex))
571 		flow_offload_teardown(flow);
572 }
573 
574 void nf_flow_table_gc_cleanup(struct nf_flowtable *flowtable,
575 			      struct net_device *dev)
576 {
577 	nf_flow_table_iterate(flowtable, nf_flow_table_do_cleanup, dev);
578 	flush_delayed_work(&flowtable->gc_work);
579 	nf_flow_table_offload_flush(flowtable);
580 }
581 
582 void nf_flow_table_cleanup(struct net_device *dev)
583 {
584 	struct nf_flowtable *flowtable;
585 
586 	mutex_lock(&flowtable_lock);
587 	list_for_each_entry(flowtable, &flowtables, list)
588 		nf_flow_table_gc_cleanup(flowtable, dev);
589 	mutex_unlock(&flowtable_lock);
590 }
591 EXPORT_SYMBOL_GPL(nf_flow_table_cleanup);
592 
593 void nf_flow_table_free(struct nf_flowtable *flow_table)
594 {
595 	mutex_lock(&flowtable_lock);
596 	list_del(&flow_table->list);
597 	mutex_unlock(&flowtable_lock);
598 
599 	cancel_delayed_work_sync(&flow_table->gc_work);
600 	nf_flow_table_offload_flush(flow_table);
601 	/* ... no more pending work after this stage ... */
602 	nf_flow_table_iterate(flow_table, nf_flow_table_do_cleanup, NULL);
603 	nf_flow_table_gc_run(flow_table);
604 	nf_flow_table_offload_flush_cleanup(flow_table);
605 	rhashtable_destroy(&flow_table->rhashtable);
606 }
607 EXPORT_SYMBOL_GPL(nf_flow_table_free);
608 
609 static int nf_flow_table_init_net(struct net *net)
610 {
611 	net->ft.stat = alloc_percpu(struct nf_flow_table_stat);
612 	return net->ft.stat ? 0 : -ENOMEM;
613 }
614 
615 static void nf_flow_table_fini_net(struct net *net)
616 {
617 	free_percpu(net->ft.stat);
618 }
619 
620 static int nf_flow_table_pernet_init(struct net *net)
621 {
622 	int ret;
623 
624 	ret = nf_flow_table_init_net(net);
625 	if (ret < 0)
626 		return ret;
627 
628 	ret = nf_flow_table_init_proc(net);
629 	if (ret < 0)
630 		goto out_proc;
631 
632 	return 0;
633 
634 out_proc:
635 	nf_flow_table_fini_net(net);
636 	return ret;
637 }
638 
639 static void nf_flow_table_pernet_exit(struct list_head *net_exit_list)
640 {
641 	struct net *net;
642 
643 	list_for_each_entry(net, net_exit_list, exit_list) {
644 		nf_flow_table_fini_proc(net);
645 		nf_flow_table_fini_net(net);
646 	}
647 }
648 
649 static struct pernet_operations nf_flow_table_net_ops = {
650 	.init = nf_flow_table_pernet_init,
651 	.exit_batch = nf_flow_table_pernet_exit,
652 };
653 
654 static int __init nf_flow_table_module_init(void)
655 {
656 	int ret;
657 
658 	ret = register_pernet_subsys(&nf_flow_table_net_ops);
659 	if (ret < 0)
660 		return ret;
661 
662 	ret = nf_flow_table_offload_init();
663 	if (ret)
664 		goto out_offload;
665 
666 	return 0;
667 
668 out_offload:
669 	unregister_pernet_subsys(&nf_flow_table_net_ops);
670 	return ret;
671 }
672 
673 static void __exit nf_flow_table_module_exit(void)
674 {
675 	nf_flow_table_offload_exit();
676 	unregister_pernet_subsys(&nf_flow_table_net_ops);
677 }
678 
679 module_init(nf_flow_table_module_init);
680 module_exit(nf_flow_table_module_exit);
681 
682 MODULE_LICENSE("GPL");
683 MODULE_AUTHOR("Pablo Neira Ayuso <pablo@netfilter.org>");
684 MODULE_DESCRIPTION("Netfilter flow table module");
685