xref: /linux/net/netfilter/nf_conntrack_proto.c (revision 3da8c3c8b8fa99505624b65ef590482f48e766b6)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <linux/types.h>
4 #include <linux/netfilter.h>
5 #include <linux/module.h>
6 #include <linux/slab.h>
7 #include <linux/mutex.h>
8 #include <linux/vmalloc.h>
9 #include <linux/stddef.h>
10 #include <linux/err.h>
11 #include <linux/percpu.h>
12 #include <linux/notifier.h>
13 #include <linux/kernel.h>
14 #include <linux/netdevice.h>
15 
16 #include <net/netfilter/nf_conntrack.h>
17 #include <net/netfilter/nf_conntrack_l4proto.h>
18 #include <net/netfilter/nf_conntrack_core.h>
19 #include <net/netfilter/nf_conntrack_bridge.h>
20 #include <net/netfilter/nf_log.h>
21 
22 #include <linux/ip.h>
23 #include <linux/icmp.h>
24 #include <linux/sysctl.h>
25 #include <net/route.h>
26 #include <net/ip.h>
27 
28 #include <linux/netfilter_ipv4.h>
29 #include <linux/netfilter_ipv6.h>
30 #include <linux/netfilter_ipv6/ip6_tables.h>
31 #include <net/netfilter/nf_conntrack_helper.h>
32 #include <net/netfilter/nf_conntrack_zones.h>
33 #include <net/netfilter/nf_conntrack_seqadj.h>
34 #include <net/netfilter/ipv4/nf_conntrack_ipv4.h>
35 #include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
36 #include <net/netfilter/nf_nat_helper.h>
37 #include <net/netfilter/ipv4/nf_defrag_ipv4.h>
38 #include <net/netfilter/ipv6/nf_defrag_ipv6.h>
39 
40 #include <linux/ipv6.h>
41 #include <linux/in6.h>
42 #include <net/ipv6.h>
43 #include <net/inet_frag.h>
44 
45 static DEFINE_MUTEX(nf_ct_proto_mutex);
46 
47 #ifdef CONFIG_SYSCTL
48 __printf(4, 5)
nf_l4proto_log_invalid(const struct sk_buff * skb,const struct nf_hook_state * state,u8 protonum,const char * fmt,...)49 void nf_l4proto_log_invalid(const struct sk_buff *skb,
50 			    const struct nf_hook_state *state,
51 			    u8 protonum,
52 			    const char *fmt, ...)
53 {
54 	struct net *net = state->net;
55 	struct va_format vaf;
56 	va_list args;
57 
58 	if (net->ct.sysctl_log_invalid != protonum &&
59 	    net->ct.sysctl_log_invalid != IPPROTO_RAW)
60 		return;
61 
62 	va_start(args, fmt);
63 	vaf.fmt = fmt;
64 	vaf.va = &args;
65 
66 	nf_log_packet(net, state->pf, 0, skb, state->in, state->out,
67 		      NULL, "nf_ct_proto_%d: %pV ", protonum, &vaf);
68 	va_end(args);
69 }
70 EXPORT_SYMBOL_GPL(nf_l4proto_log_invalid);
71 
72 __printf(4, 5)
nf_ct_l4proto_log_invalid(const struct sk_buff * skb,const struct nf_conn * ct,const struct nf_hook_state * state,const char * fmt,...)73 void nf_ct_l4proto_log_invalid(const struct sk_buff *skb,
74 			       const struct nf_conn *ct,
75 			       const struct nf_hook_state *state,
76 			       const char *fmt, ...)
77 {
78 	struct va_format vaf;
79 	struct net *net;
80 	va_list args;
81 
82 	/* nfnetlink_log may re-enter conntrack attribute dumping and try to
83 	 * take ct->lock again via helpers such as tcp_to_nlattr(), so invalid
84 	 * conntrack logs must only be emitted after dropping ct->lock.
85 	 */
86 	lockdep_assert_not_held(&ct->lock);
87 
88 	net = nf_ct_net(ct);
89 	if (likely(net->ct.sysctl_log_invalid == 0))
90 		return;
91 
92 	va_start(args, fmt);
93 	vaf.fmt = fmt;
94 	vaf.va = &args;
95 
96 	nf_l4proto_log_invalid(skb, state,
97 			       nf_ct_protonum(ct), "%pV", &vaf);
98 	va_end(args);
99 }
100 EXPORT_SYMBOL_GPL(nf_ct_l4proto_log_invalid);
101 #endif
102 
nf_ct_l4proto_find(u8 l4proto)103 const struct nf_conntrack_l4proto *nf_ct_l4proto_find(u8 l4proto)
104 {
105 	switch (l4proto) {
106 	case IPPROTO_UDP: return &nf_conntrack_l4proto_udp;
107 	case IPPROTO_TCP: return &nf_conntrack_l4proto_tcp;
108 	case IPPROTO_ICMP: return &nf_conntrack_l4proto_icmp;
109 #ifdef CONFIG_NF_CT_PROTO_SCTP
110 	case IPPROTO_SCTP: return &nf_conntrack_l4proto_sctp;
111 #endif
112 #ifdef CONFIG_NF_CT_PROTO_GRE
113 	case IPPROTO_GRE: return &nf_conntrack_l4proto_gre;
114 #endif
115 #if IS_ENABLED(CONFIG_IPV6)
116 	case IPPROTO_ICMPV6: return &nf_conntrack_l4proto_icmpv6;
117 #endif /* CONFIG_IPV6 */
118 	}
119 
120 	return &nf_conntrack_l4proto_generic;
121 };
122 EXPORT_SYMBOL_GPL(nf_ct_l4proto_find);
123 
in_vrf_postrouting(const struct nf_hook_state * state)124 static bool in_vrf_postrouting(const struct nf_hook_state *state)
125 {
126 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
127 	if (state->hook == NF_INET_POST_ROUTING &&
128 	    netif_is_l3_master(state->out))
129 		return true;
130 #endif
131 	return false;
132 }
133 
nf_confirm(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)134 unsigned int nf_confirm(void *priv,
135 			struct sk_buff *skb,
136 			const struct nf_hook_state *state)
137 {
138 	int (*helper_cb)(struct sk_buff *skb, unsigned int protoff,
139 			 struct nf_conn *ct,
140 			 enum ip_conntrack_info conntrackinfo);
141 	const struct nf_conn_help *help;
142 	enum ip_conntrack_info ctinfo;
143 	unsigned int protoff;
144 	struct nf_conn *ct;
145 	bool seqadj_needed;
146 	__be16 frag_off;
147 	int start;
148 	u8 pnum;
149 
150 	ct = nf_ct_get(skb, &ctinfo);
151 	if (!ct || in_vrf_postrouting(state))
152 		return NF_ACCEPT;
153 
154 	help = nfct_help(ct);
155 
156 	seqadj_needed = test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && !nf_is_loopback_packet(skb);
157 	if (!help && !seqadj_needed)
158 		return nf_conntrack_confirm(skb);
159 
160 	/* helper->help() do not expect ICMP packets */
161 	if (ctinfo == IP_CT_RELATED_REPLY)
162 		return nf_conntrack_confirm(skb);
163 
164 	switch (nf_ct_l3num(ct)) {
165 	case NFPROTO_IPV4:
166 		protoff = skb_network_offset(skb) + ip_hdrlen(skb);
167 		break;
168 	case NFPROTO_IPV6:
169 		pnum = ipv6_hdr(skb)->nexthdr;
170 		start = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum, &frag_off);
171 		if (start < 0 || (frag_off & htons(~0x7)) != 0)
172 			return nf_conntrack_confirm(skb);
173 
174 		protoff = start;
175 		break;
176 	default:
177 		return nf_conntrack_confirm(skb);
178 	}
179 
180 	if (help) {
181 		const struct nf_conntrack_helper *helper;
182 		int ret;
183 
184 		/* rcu_read_lock()ed by nf_hook */
185 		helper = rcu_dereference(help->helper);
186 		if (helper) {
187 			helper_cb = rcu_dereference(helper->help);
188 			if (helper_cb) {
189 				ret = helper_cb(skb, protoff,
190 						ct, ctinfo);
191 				if (ret != NF_ACCEPT)
192 					return ret;
193 			}
194 		}
195 	}
196 
197 	if (seqadj_needed &&
198 	    !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
199 		NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
200 		return NF_DROP;
201 	}
202 
203 	/* We've seen it coming out the other side: confirm it */
204 	return nf_conntrack_confirm(skb);
205 }
206 EXPORT_SYMBOL_GPL(nf_confirm);
207 
ipv4_conntrack_in(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)208 static unsigned int ipv4_conntrack_in(void *priv,
209 				      struct sk_buff *skb,
210 				      const struct nf_hook_state *state)
211 {
212 	return nf_conntrack_in(skb, state);
213 }
214 
ipv4_conntrack_local(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)215 static unsigned int ipv4_conntrack_local(void *priv,
216 					 struct sk_buff *skb,
217 					 const struct nf_hook_state *state)
218 {
219 	if (ip_is_fragment(ip_hdr(skb))) { /* IP_NODEFRAG setsockopt set */
220 		enum ip_conntrack_info ctinfo;
221 		struct nf_conn *tmpl;
222 
223 		tmpl = nf_ct_get(skb, &ctinfo);
224 		if (tmpl && nf_ct_is_template(tmpl)) {
225 			/* when skipping ct, clear templates to avoid fooling
226 			 * later targets/matches
227 			 */
228 			skb->_nfct = 0;
229 			nf_ct_put(tmpl);
230 		}
231 		return NF_ACCEPT;
232 	}
233 
234 	return nf_conntrack_in(skb, state);
235 }
236 
237 /* Connection tracking may drop packets, but never alters them, so
238  * make it the first hook.
239  */
240 static const struct nf_hook_ops ipv4_conntrack_ops[] = {
241 	{
242 		.hook		= ipv4_conntrack_in,
243 		.pf		= NFPROTO_IPV4,
244 		.hooknum	= NF_INET_PRE_ROUTING,
245 		.priority	= NF_IP_PRI_CONNTRACK,
246 	},
247 	{
248 		.hook		= ipv4_conntrack_local,
249 		.pf		= NFPROTO_IPV4,
250 		.hooknum	= NF_INET_LOCAL_OUT,
251 		.priority	= NF_IP_PRI_CONNTRACK,
252 	},
253 	{
254 		.hook		= nf_confirm,
255 		.pf		= NFPROTO_IPV4,
256 		.hooknum	= NF_INET_POST_ROUTING,
257 		.priority	= NF_IP_PRI_CONNTRACK_CONFIRM,
258 	},
259 	{
260 		.hook		= nf_confirm,
261 		.pf		= NFPROTO_IPV4,
262 		.hooknum	= NF_INET_LOCAL_IN,
263 		.priority	= NF_IP_PRI_CONNTRACK_CONFIRM,
264 	},
265 };
266 
267 /* Fast function for those who don't want to parse /proc (and I don't
268  * blame them).
269  * Reversing the socket's dst/src point of view gives us the reply
270  * mapping.
271  */
272 static int
getorigdst(struct sock * sk,int optval,void __user * user,int * len)273 getorigdst(struct sock *sk, int optval, void __user *user, int *len)
274 {
275 	const struct inet_sock *inet = inet_sk(sk);
276 	const struct nf_conntrack_tuple_hash *h;
277 	struct nf_conntrack_tuple tuple;
278 
279 	memset(&tuple, 0, sizeof(tuple));
280 
281 	lock_sock(sk);
282 	tuple.src.u3.ip = inet->inet_rcv_saddr;
283 	tuple.src.u.tcp.port = inet->inet_sport;
284 	tuple.dst.u3.ip = inet->inet_daddr;
285 	tuple.dst.u.tcp.port = inet->inet_dport;
286 	tuple.src.l3num = PF_INET;
287 	tuple.dst.protonum = sk->sk_protocol;
288 	release_sock(sk);
289 
290 	/* We only do TCP and SCTP at the moment: is there a better way? */
291 	if (tuple.dst.protonum != IPPROTO_TCP &&
292 	    tuple.dst.protonum != IPPROTO_SCTP)
293 		return -ENOPROTOOPT;
294 
295 	if ((unsigned int)*len < sizeof(struct sockaddr_in))
296 		return -EINVAL;
297 
298 	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
299 	if (h) {
300 		struct sockaddr_in sin;
301 		struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
302 
303 		sin.sin_family = AF_INET;
304 		sin.sin_port = ct->tuplehash[IP_CT_DIR_ORIGINAL]
305 			.tuple.dst.u.tcp.port;
306 		sin.sin_addr.s_addr = ct->tuplehash[IP_CT_DIR_ORIGINAL]
307 			.tuple.dst.u3.ip;
308 		memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
309 
310 		nf_ct_put(ct);
311 		if (copy_to_user(user, &sin, sizeof(sin)) != 0)
312 			return -EFAULT;
313 		else
314 			return 0;
315 	}
316 	return -ENOENT;
317 }
318 
319 static struct nf_sockopt_ops so_getorigdst = {
320 	.pf		= PF_INET,
321 	.get_optmin	= SO_ORIGINAL_DST,
322 	.get_optmax	= SO_ORIGINAL_DST + 1,
323 	.get		= getorigdst,
324 	.owner		= THIS_MODULE,
325 };
326 
327 #if IS_ENABLED(CONFIG_IPV6)
328 static int
ipv6_getorigdst(struct sock * sk,int optval,void __user * user,int * len)329 ipv6_getorigdst(struct sock *sk, int optval, void __user *user, int *len)
330 {
331 	struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
332 	const struct ipv6_pinfo *inet6 = inet6_sk(sk);
333 	const struct inet_sock *inet = inet_sk(sk);
334 	const struct nf_conntrack_tuple_hash *h;
335 	struct sockaddr_in6 sin6;
336 	struct nf_conn *ct;
337 	__be32 flow_label;
338 	int bound_dev_if;
339 
340 	lock_sock(sk);
341 	tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
342 	tuple.src.u.tcp.port = inet->inet_sport;
343 	tuple.dst.u3.in6 = sk->sk_v6_daddr;
344 	tuple.dst.u.tcp.port = inet->inet_dport;
345 	tuple.dst.protonum = sk->sk_protocol;
346 	bound_dev_if = sk->sk_bound_dev_if;
347 	flow_label = inet6->flow_label;
348 	release_sock(sk);
349 
350 	if (tuple.dst.protonum != IPPROTO_TCP &&
351 	    tuple.dst.protonum != IPPROTO_SCTP)
352 		return -ENOPROTOOPT;
353 
354 	if (*len < 0 || (unsigned int)*len < sizeof(sin6))
355 		return -EINVAL;
356 
357 	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
358 	if (!h)
359 		return -ENOENT;
360 
361 	ct = nf_ct_tuplehash_to_ctrack(h);
362 
363 	sin6.sin6_family = AF_INET6;
364 	sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
365 	sin6.sin6_flowinfo = flow_label & IPV6_FLOWINFO_MASK;
366 	memcpy(&sin6.sin6_addr,
367 	       &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
368 	       sizeof(sin6.sin6_addr));
369 
370 	nf_ct_put(ct);
371 	sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr, bound_dev_if);
372 	return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
373 }
374 
375 static struct nf_sockopt_ops so_getorigdst6 = {
376 	.pf		= NFPROTO_IPV6,
377 	.get_optmin	= IP6T_SO_ORIGINAL_DST,
378 	.get_optmax	= IP6T_SO_ORIGINAL_DST + 1,
379 	.get		= ipv6_getorigdst,
380 	.owner		= THIS_MODULE,
381 };
382 
ipv6_conntrack_in(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)383 static unsigned int ipv6_conntrack_in(void *priv,
384 				      struct sk_buff *skb,
385 				      const struct nf_hook_state *state)
386 {
387 	return nf_conntrack_in(skb, state);
388 }
389 
ipv6_conntrack_local(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)390 static unsigned int ipv6_conntrack_local(void *priv,
391 					 struct sk_buff *skb,
392 					 const struct nf_hook_state *state)
393 {
394 	return nf_conntrack_in(skb, state);
395 }
396 
397 static const struct nf_hook_ops ipv6_conntrack_ops[] = {
398 	{
399 		.hook		= ipv6_conntrack_in,
400 		.pf		= NFPROTO_IPV6,
401 		.hooknum	= NF_INET_PRE_ROUTING,
402 		.priority	= NF_IP6_PRI_CONNTRACK,
403 	},
404 	{
405 		.hook		= ipv6_conntrack_local,
406 		.pf		= NFPROTO_IPV6,
407 		.hooknum	= NF_INET_LOCAL_OUT,
408 		.priority	= NF_IP6_PRI_CONNTRACK,
409 	},
410 	{
411 		.hook		= nf_confirm,
412 		.pf		= NFPROTO_IPV6,
413 		.hooknum	= NF_INET_POST_ROUTING,
414 		.priority	= NF_IP6_PRI_LAST,
415 	},
416 	{
417 		.hook		= nf_confirm,
418 		.pf		= NFPROTO_IPV6,
419 		.hooknum	= NF_INET_LOCAL_IN,
420 		.priority	= NF_IP6_PRI_LAST - 1,
421 	},
422 };
423 #endif
424 
nf_ct_tcp_fixup(struct nf_conn * ct,void * _nfproto)425 static int nf_ct_tcp_fixup(struct nf_conn *ct, void *_nfproto)
426 {
427 	u8 nfproto = (unsigned long)_nfproto;
428 
429 	if (nf_ct_l3num(ct) != nfproto)
430 		return 0;
431 
432 	if (nf_ct_protonum(ct) == IPPROTO_TCP &&
433 	    ct->proto.tcp.state == TCP_CONNTRACK_ESTABLISHED) {
434 		ct->proto.tcp.seen[0].td_maxwin = 0;
435 		ct->proto.tcp.seen[1].td_maxwin = 0;
436 	}
437 
438 	return 0;
439 }
440 
441 static struct nf_ct_bridge_info *nf_ct_bridge_info;
442 
nf_ct_netns_do_get(struct net * net,u8 nfproto)443 static int nf_ct_netns_do_get(struct net *net, u8 nfproto)
444 {
445 	struct nf_conntrack_net *cnet = nf_ct_pernet(net);
446 	bool fixup_needed = false, retry = true;
447 	int err = 0;
448 retry:
449 	mutex_lock(&nf_ct_proto_mutex);
450 
451 	switch (nfproto) {
452 	case NFPROTO_IPV4:
453 		cnet->users4++;
454 		if (cnet->users4 > 1)
455 			goto out_unlock;
456 		err = nf_defrag_ipv4_enable(net);
457 		if (err) {
458 			cnet->users4 = 0;
459 			goto out_unlock;
460 		}
461 
462 		err = nf_register_net_hooks(net, ipv4_conntrack_ops,
463 					    ARRAY_SIZE(ipv4_conntrack_ops));
464 		if (err)
465 			cnet->users4 = 0;
466 		else
467 			fixup_needed = true;
468 		break;
469 #if IS_ENABLED(CONFIG_IPV6)
470 	case NFPROTO_IPV6:
471 		cnet->users6++;
472 		if (cnet->users6 > 1)
473 			goto out_unlock;
474 		err = nf_defrag_ipv6_enable(net);
475 		if (err < 0) {
476 			cnet->users6 = 0;
477 			goto out_unlock;
478 		}
479 
480 		err = nf_register_net_hooks(net, ipv6_conntrack_ops,
481 					    ARRAY_SIZE(ipv6_conntrack_ops));
482 		if (err)
483 			cnet->users6 = 0;
484 		else
485 			fixup_needed = true;
486 		break;
487 #endif
488 	case NFPROTO_BRIDGE:
489 		if (!nf_ct_bridge_info) {
490 			if (!retry) {
491 				err = -EPROTO;
492 				goto out_unlock;
493 			}
494 			mutex_unlock(&nf_ct_proto_mutex);
495 			request_module("nf_conntrack_bridge");
496 			retry = false;
497 			goto retry;
498 		}
499 		if (!try_module_get(nf_ct_bridge_info->me)) {
500 			err = -EPROTO;
501 			goto out_unlock;
502 		}
503 		cnet->users_bridge++;
504 		if (cnet->users_bridge > 1)
505 			goto out_unlock;
506 
507 		err = nf_register_net_hooks(net, nf_ct_bridge_info->ops,
508 					    nf_ct_bridge_info->ops_size);
509 		if (err)
510 			cnet->users_bridge = 0;
511 		else
512 			fixup_needed = true;
513 		break;
514 	default:
515 		err = -EPROTO;
516 		break;
517 	}
518  out_unlock:
519 	mutex_unlock(&nf_ct_proto_mutex);
520 
521 	if (fixup_needed) {
522 		struct nf_ct_iter_data iter_data = {
523 			.net	= net,
524 			.data	= (void *)(unsigned long)nfproto,
525 		};
526 		nf_ct_iterate_cleanup_net(nf_ct_tcp_fixup, &iter_data);
527 	}
528 
529 	return err;
530 }
531 
nf_ct_netns_do_put(struct net * net,u8 nfproto)532 static void nf_ct_netns_do_put(struct net *net, u8 nfproto)
533 {
534 	struct nf_conntrack_net *cnet = nf_ct_pernet(net);
535 
536 	mutex_lock(&nf_ct_proto_mutex);
537 	switch (nfproto) {
538 	case NFPROTO_IPV4:
539 		if (cnet->users4 && (--cnet->users4 == 0)) {
540 			nf_unregister_net_hooks(net, ipv4_conntrack_ops,
541 						ARRAY_SIZE(ipv4_conntrack_ops));
542 			nf_defrag_ipv4_disable(net);
543 		}
544 		break;
545 #if IS_ENABLED(CONFIG_IPV6)
546 	case NFPROTO_IPV6:
547 		if (cnet->users6 && (--cnet->users6 == 0)) {
548 			nf_unregister_net_hooks(net, ipv6_conntrack_ops,
549 						ARRAY_SIZE(ipv6_conntrack_ops));
550 			nf_defrag_ipv6_disable(net);
551 		}
552 		break;
553 #endif
554 	case NFPROTO_BRIDGE:
555 		if (!nf_ct_bridge_info)
556 			break;
557 		if (cnet->users_bridge && (--cnet->users_bridge == 0))
558 			nf_unregister_net_hooks(net, nf_ct_bridge_info->ops,
559 						nf_ct_bridge_info->ops_size);
560 
561 		module_put(nf_ct_bridge_info->me);
562 		break;
563 	}
564 	mutex_unlock(&nf_ct_proto_mutex);
565 }
566 
nf_ct_netns_inet_get(struct net * net)567 static int nf_ct_netns_inet_get(struct net *net)
568 {
569 	int err;
570 
571 	err = nf_ct_netns_do_get(net, NFPROTO_IPV4);
572 #if IS_ENABLED(CONFIG_IPV6)
573 	if (err < 0)
574 		goto err1;
575 	err = nf_ct_netns_do_get(net, NFPROTO_IPV6);
576 	if (err < 0)
577 		goto err2;
578 
579 	return err;
580 err2:
581 	nf_ct_netns_put(net, NFPROTO_IPV4);
582 err1:
583 #endif
584 	return err;
585 }
586 
nf_ct_netns_get(struct net * net,u8 nfproto)587 int nf_ct_netns_get(struct net *net, u8 nfproto)
588 {
589 	int err;
590 
591 	switch (nfproto) {
592 	case NFPROTO_INET:
593 		err = nf_ct_netns_inet_get(net);
594 		break;
595 	case NFPROTO_BRIDGE:
596 		err = nf_ct_netns_do_get(net, NFPROTO_BRIDGE);
597 		if (err < 0)
598 			return err;
599 
600 		err = nf_ct_netns_inet_get(net);
601 		if (err < 0) {
602 			nf_ct_netns_put(net, NFPROTO_BRIDGE);
603 			return err;
604 		}
605 		break;
606 	default:
607 		err = nf_ct_netns_do_get(net, nfproto);
608 		break;
609 	}
610 	return err;
611 }
612 EXPORT_SYMBOL_GPL(nf_ct_netns_get);
613 
nf_ct_netns_put(struct net * net,uint8_t nfproto)614 void nf_ct_netns_put(struct net *net, uint8_t nfproto)
615 {
616 	switch (nfproto) {
617 	case NFPROTO_BRIDGE:
618 		nf_ct_netns_do_put(net, NFPROTO_BRIDGE);
619 		fallthrough;
620 	case NFPROTO_INET:
621 		nf_ct_netns_do_put(net, NFPROTO_IPV4);
622 		nf_ct_netns_do_put(net, NFPROTO_IPV6);
623 		break;
624 	default:
625 		nf_ct_netns_do_put(net, nfproto);
626 		break;
627 	}
628 }
629 EXPORT_SYMBOL_GPL(nf_ct_netns_put);
630 
nf_ct_bridge_register(struct nf_ct_bridge_info * info)631 void nf_ct_bridge_register(struct nf_ct_bridge_info *info)
632 {
633 	WARN_ON(nf_ct_bridge_info);
634 	mutex_lock(&nf_ct_proto_mutex);
635 	nf_ct_bridge_info = info;
636 	mutex_unlock(&nf_ct_proto_mutex);
637 }
638 EXPORT_SYMBOL_GPL(nf_ct_bridge_register);
639 
nf_ct_bridge_unregister(struct nf_ct_bridge_info * info)640 void nf_ct_bridge_unregister(struct nf_ct_bridge_info *info)
641 {
642 	WARN_ON(!nf_ct_bridge_info);
643 	mutex_lock(&nf_ct_proto_mutex);
644 	nf_ct_bridge_info = NULL;
645 	mutex_unlock(&nf_ct_proto_mutex);
646 }
647 EXPORT_SYMBOL_GPL(nf_ct_bridge_unregister);
648 
nf_conntrack_proto_init(void)649 int nf_conntrack_proto_init(void)
650 {
651 	int ret;
652 
653 	ret = nf_register_sockopt(&so_getorigdst);
654 	if (ret < 0)
655 		return ret;
656 
657 #if IS_ENABLED(CONFIG_IPV6)
658 	ret = nf_register_sockopt(&so_getorigdst6);
659 	if (ret < 0)
660 		goto cleanup_sockopt;
661 #endif
662 
663 	return ret;
664 
665 #if IS_ENABLED(CONFIG_IPV6)
666 cleanup_sockopt:
667 	nf_unregister_sockopt(&so_getorigdst);
668 #endif
669 	return ret;
670 }
671 
nf_conntrack_proto_fini(void)672 void nf_conntrack_proto_fini(void)
673 {
674 	nf_unregister_sockopt(&so_getorigdst);
675 #if IS_ENABLED(CONFIG_IPV6)
676 	nf_unregister_sockopt(&so_getorigdst6);
677 #endif
678 }
679 
nf_conntrack_proto_pernet_init(struct net * net)680 void nf_conntrack_proto_pernet_init(struct net *net)
681 {
682 	nf_conntrack_generic_init_net(net);
683 	nf_conntrack_udp_init_net(net);
684 	nf_conntrack_tcp_init_net(net);
685 	nf_conntrack_icmp_init_net(net);
686 #if IS_ENABLED(CONFIG_IPV6)
687 	nf_conntrack_icmpv6_init_net(net);
688 #endif
689 #ifdef CONFIG_NF_CT_PROTO_SCTP
690 	nf_conntrack_sctp_init_net(net);
691 #endif
692 #ifdef CONFIG_NF_CT_PROTO_GRE
693 	nf_conntrack_gre_init_net(net);
694 #endif
695 }
696 
697 module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
698 		  &nf_conntrack_htable_size, 0600);
699 
700 MODULE_ALIAS("ip_conntrack");
701 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET));
702 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
703 MODULE_LICENSE("GPL");
704 MODULE_DESCRIPTION("IPv4 and IPv6 connection tracking");
705