xref: /linux/net/netfilter/nf_conntrack_proto.c (revision 8be4d31cb8aaeea27bde4b7ddb26e28a89062ebf)
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 	net = nf_ct_net(ct);
83 	if (likely(net->ct.sysctl_log_invalid == 0))
84 		return;
85 
86 	va_start(args, fmt);
87 	vaf.fmt = fmt;
88 	vaf.va = &args;
89 
90 	nf_l4proto_log_invalid(skb, state,
91 			       nf_ct_protonum(ct), "%pV", &vaf);
92 	va_end(args);
93 }
94 EXPORT_SYMBOL_GPL(nf_ct_l4proto_log_invalid);
95 #endif
96 
nf_ct_l4proto_find(u8 l4proto)97 const struct nf_conntrack_l4proto *nf_ct_l4proto_find(u8 l4proto)
98 {
99 	switch (l4proto) {
100 	case IPPROTO_UDP: return &nf_conntrack_l4proto_udp;
101 	case IPPROTO_TCP: return &nf_conntrack_l4proto_tcp;
102 	case IPPROTO_ICMP: return &nf_conntrack_l4proto_icmp;
103 #ifdef CONFIG_NF_CT_PROTO_SCTP
104 	case IPPROTO_SCTP: return &nf_conntrack_l4proto_sctp;
105 #endif
106 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
107 	case IPPROTO_UDPLITE: return &nf_conntrack_l4proto_udplite;
108 #endif
109 #ifdef CONFIG_NF_CT_PROTO_GRE
110 	case IPPROTO_GRE: return &nf_conntrack_l4proto_gre;
111 #endif
112 #if IS_ENABLED(CONFIG_IPV6)
113 	case IPPROTO_ICMPV6: return &nf_conntrack_l4proto_icmpv6;
114 #endif /* CONFIG_IPV6 */
115 	}
116 
117 	return &nf_conntrack_l4proto_generic;
118 };
119 EXPORT_SYMBOL_GPL(nf_ct_l4proto_find);
120 
in_vrf_postrouting(const struct nf_hook_state * state)121 static bool in_vrf_postrouting(const struct nf_hook_state *state)
122 {
123 #if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
124 	if (state->hook == NF_INET_POST_ROUTING &&
125 	    netif_is_l3_master(state->out))
126 		return true;
127 #endif
128 	return false;
129 }
130 
nf_confirm(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)131 unsigned int nf_confirm(void *priv,
132 			struct sk_buff *skb,
133 			const struct nf_hook_state *state)
134 {
135 	const struct nf_conn_help *help;
136 	enum ip_conntrack_info ctinfo;
137 	unsigned int protoff;
138 	struct nf_conn *ct;
139 	bool seqadj_needed;
140 	__be16 frag_off;
141 	int start;
142 	u8 pnum;
143 
144 	ct = nf_ct_get(skb, &ctinfo);
145 	if (!ct || in_vrf_postrouting(state))
146 		return NF_ACCEPT;
147 
148 	help = nfct_help(ct);
149 
150 	seqadj_needed = test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) && !nf_is_loopback_packet(skb);
151 	if (!help && !seqadj_needed)
152 		return nf_conntrack_confirm(skb);
153 
154 	/* helper->help() do not expect ICMP packets */
155 	if (ctinfo == IP_CT_RELATED_REPLY)
156 		return nf_conntrack_confirm(skb);
157 
158 	switch (nf_ct_l3num(ct)) {
159 	case NFPROTO_IPV4:
160 		protoff = skb_network_offset(skb) + ip_hdrlen(skb);
161 		break;
162 	case NFPROTO_IPV6:
163 		pnum = ipv6_hdr(skb)->nexthdr;
164 		start = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum, &frag_off);
165 		if (start < 0 || (frag_off & htons(~0x7)) != 0)
166 			return nf_conntrack_confirm(skb);
167 
168 		protoff = start;
169 		break;
170 	default:
171 		return nf_conntrack_confirm(skb);
172 	}
173 
174 	if (help) {
175 		const struct nf_conntrack_helper *helper;
176 		int ret;
177 
178 		/* rcu_read_lock()ed by nf_hook */
179 		helper = rcu_dereference(help->helper);
180 		if (helper) {
181 			ret = helper->help(skb,
182 					   protoff,
183 					   ct, ctinfo);
184 			if (ret != NF_ACCEPT)
185 				return ret;
186 		}
187 	}
188 
189 	if (seqadj_needed &&
190 	    !nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
191 		NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
192 		return NF_DROP;
193 	}
194 
195 	/* We've seen it coming out the other side: confirm it */
196 	return nf_conntrack_confirm(skb);
197 }
198 EXPORT_SYMBOL_GPL(nf_confirm);
199 
ipv4_conntrack_in(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)200 static unsigned int ipv4_conntrack_in(void *priv,
201 				      struct sk_buff *skb,
202 				      const struct nf_hook_state *state)
203 {
204 	return nf_conntrack_in(skb, state);
205 }
206 
ipv4_conntrack_local(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)207 static unsigned int ipv4_conntrack_local(void *priv,
208 					 struct sk_buff *skb,
209 					 const struct nf_hook_state *state)
210 {
211 	if (ip_is_fragment(ip_hdr(skb))) { /* IP_NODEFRAG setsockopt set */
212 		enum ip_conntrack_info ctinfo;
213 		struct nf_conn *tmpl;
214 
215 		tmpl = nf_ct_get(skb, &ctinfo);
216 		if (tmpl && nf_ct_is_template(tmpl)) {
217 			/* when skipping ct, clear templates to avoid fooling
218 			 * later targets/matches
219 			 */
220 			skb->_nfct = 0;
221 			nf_ct_put(tmpl);
222 		}
223 		return NF_ACCEPT;
224 	}
225 
226 	return nf_conntrack_in(skb, state);
227 }
228 
229 /* Connection tracking may drop packets, but never alters them, so
230  * make it the first hook.
231  */
232 static const struct nf_hook_ops ipv4_conntrack_ops[] = {
233 	{
234 		.hook		= ipv4_conntrack_in,
235 		.pf		= NFPROTO_IPV4,
236 		.hooknum	= NF_INET_PRE_ROUTING,
237 		.priority	= NF_IP_PRI_CONNTRACK,
238 	},
239 	{
240 		.hook		= ipv4_conntrack_local,
241 		.pf		= NFPROTO_IPV4,
242 		.hooknum	= NF_INET_LOCAL_OUT,
243 		.priority	= NF_IP_PRI_CONNTRACK,
244 	},
245 	{
246 		.hook		= nf_confirm,
247 		.pf		= NFPROTO_IPV4,
248 		.hooknum	= NF_INET_POST_ROUTING,
249 		.priority	= NF_IP_PRI_CONNTRACK_CONFIRM,
250 	},
251 	{
252 		.hook		= nf_confirm,
253 		.pf		= NFPROTO_IPV4,
254 		.hooknum	= NF_INET_LOCAL_IN,
255 		.priority	= NF_IP_PRI_CONNTRACK_CONFIRM,
256 	},
257 };
258 
259 /* Fast function for those who don't want to parse /proc (and I don't
260  * blame them).
261  * Reversing the socket's dst/src point of view gives us the reply
262  * mapping.
263  */
264 static int
getorigdst(struct sock * sk,int optval,void __user * user,int * len)265 getorigdst(struct sock *sk, int optval, void __user *user, int *len)
266 {
267 	const struct inet_sock *inet = inet_sk(sk);
268 	const struct nf_conntrack_tuple_hash *h;
269 	struct nf_conntrack_tuple tuple;
270 
271 	memset(&tuple, 0, sizeof(tuple));
272 
273 	lock_sock(sk);
274 	tuple.src.u3.ip = inet->inet_rcv_saddr;
275 	tuple.src.u.tcp.port = inet->inet_sport;
276 	tuple.dst.u3.ip = inet->inet_daddr;
277 	tuple.dst.u.tcp.port = inet->inet_dport;
278 	tuple.src.l3num = PF_INET;
279 	tuple.dst.protonum = sk->sk_protocol;
280 	release_sock(sk);
281 
282 	/* We only do TCP and SCTP at the moment: is there a better way? */
283 	if (tuple.dst.protonum != IPPROTO_TCP &&
284 	    tuple.dst.protonum != IPPROTO_SCTP)
285 		return -ENOPROTOOPT;
286 
287 	if ((unsigned int)*len < sizeof(struct sockaddr_in))
288 		return -EINVAL;
289 
290 	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
291 	if (h) {
292 		struct sockaddr_in sin;
293 		struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
294 
295 		sin.sin_family = AF_INET;
296 		sin.sin_port = ct->tuplehash[IP_CT_DIR_ORIGINAL]
297 			.tuple.dst.u.tcp.port;
298 		sin.sin_addr.s_addr = ct->tuplehash[IP_CT_DIR_ORIGINAL]
299 			.tuple.dst.u3.ip;
300 		memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
301 
302 		nf_ct_put(ct);
303 		if (copy_to_user(user, &sin, sizeof(sin)) != 0)
304 			return -EFAULT;
305 		else
306 			return 0;
307 	}
308 	return -ENOENT;
309 }
310 
311 static struct nf_sockopt_ops so_getorigdst = {
312 	.pf		= PF_INET,
313 	.get_optmin	= SO_ORIGINAL_DST,
314 	.get_optmax	= SO_ORIGINAL_DST + 1,
315 	.get		= getorigdst,
316 	.owner		= THIS_MODULE,
317 };
318 
319 #if IS_ENABLED(CONFIG_IPV6)
320 static int
ipv6_getorigdst(struct sock * sk,int optval,void __user * user,int * len)321 ipv6_getorigdst(struct sock *sk, int optval, void __user *user, int *len)
322 {
323 	struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
324 	const struct ipv6_pinfo *inet6 = inet6_sk(sk);
325 	const struct inet_sock *inet = inet_sk(sk);
326 	const struct nf_conntrack_tuple_hash *h;
327 	struct sockaddr_in6 sin6;
328 	struct nf_conn *ct;
329 	__be32 flow_label;
330 	int bound_dev_if;
331 
332 	lock_sock(sk);
333 	tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
334 	tuple.src.u.tcp.port = inet->inet_sport;
335 	tuple.dst.u3.in6 = sk->sk_v6_daddr;
336 	tuple.dst.u.tcp.port = inet->inet_dport;
337 	tuple.dst.protonum = sk->sk_protocol;
338 	bound_dev_if = sk->sk_bound_dev_if;
339 	flow_label = inet6->flow_label;
340 	release_sock(sk);
341 
342 	if (tuple.dst.protonum != IPPROTO_TCP &&
343 	    tuple.dst.protonum != IPPROTO_SCTP)
344 		return -ENOPROTOOPT;
345 
346 	if (*len < 0 || (unsigned int)*len < sizeof(sin6))
347 		return -EINVAL;
348 
349 	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
350 	if (!h)
351 		return -ENOENT;
352 
353 	ct = nf_ct_tuplehash_to_ctrack(h);
354 
355 	sin6.sin6_family = AF_INET6;
356 	sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
357 	sin6.sin6_flowinfo = flow_label & IPV6_FLOWINFO_MASK;
358 	memcpy(&sin6.sin6_addr,
359 	       &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
360 	       sizeof(sin6.sin6_addr));
361 
362 	nf_ct_put(ct);
363 	sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr, bound_dev_if);
364 	return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
365 }
366 
367 static struct nf_sockopt_ops so_getorigdst6 = {
368 	.pf		= NFPROTO_IPV6,
369 	.get_optmin	= IP6T_SO_ORIGINAL_DST,
370 	.get_optmax	= IP6T_SO_ORIGINAL_DST + 1,
371 	.get		= ipv6_getorigdst,
372 	.owner		= THIS_MODULE,
373 };
374 
ipv6_conntrack_in(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)375 static unsigned int ipv6_conntrack_in(void *priv,
376 				      struct sk_buff *skb,
377 				      const struct nf_hook_state *state)
378 {
379 	return nf_conntrack_in(skb, state);
380 }
381 
ipv6_conntrack_local(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)382 static unsigned int ipv6_conntrack_local(void *priv,
383 					 struct sk_buff *skb,
384 					 const struct nf_hook_state *state)
385 {
386 	return nf_conntrack_in(skb, state);
387 }
388 
389 static const struct nf_hook_ops ipv6_conntrack_ops[] = {
390 	{
391 		.hook		= ipv6_conntrack_in,
392 		.pf		= NFPROTO_IPV6,
393 		.hooknum	= NF_INET_PRE_ROUTING,
394 		.priority	= NF_IP6_PRI_CONNTRACK,
395 	},
396 	{
397 		.hook		= ipv6_conntrack_local,
398 		.pf		= NFPROTO_IPV6,
399 		.hooknum	= NF_INET_LOCAL_OUT,
400 		.priority	= NF_IP6_PRI_CONNTRACK,
401 	},
402 	{
403 		.hook		= nf_confirm,
404 		.pf		= NFPROTO_IPV6,
405 		.hooknum	= NF_INET_POST_ROUTING,
406 		.priority	= NF_IP6_PRI_LAST,
407 	},
408 	{
409 		.hook		= nf_confirm,
410 		.pf		= NFPROTO_IPV6,
411 		.hooknum	= NF_INET_LOCAL_IN,
412 		.priority	= NF_IP6_PRI_LAST - 1,
413 	},
414 };
415 #endif
416 
nf_ct_tcp_fixup(struct nf_conn * ct,void * _nfproto)417 static int nf_ct_tcp_fixup(struct nf_conn *ct, void *_nfproto)
418 {
419 	u8 nfproto = (unsigned long)_nfproto;
420 
421 	if (nf_ct_l3num(ct) != nfproto)
422 		return 0;
423 
424 	if (nf_ct_protonum(ct) == IPPROTO_TCP &&
425 	    ct->proto.tcp.state == TCP_CONNTRACK_ESTABLISHED) {
426 		ct->proto.tcp.seen[0].td_maxwin = 0;
427 		ct->proto.tcp.seen[1].td_maxwin = 0;
428 	}
429 
430 	return 0;
431 }
432 
433 static struct nf_ct_bridge_info *nf_ct_bridge_info;
434 
nf_ct_netns_do_get(struct net * net,u8 nfproto)435 static int nf_ct_netns_do_get(struct net *net, u8 nfproto)
436 {
437 	struct nf_conntrack_net *cnet = nf_ct_pernet(net);
438 	bool fixup_needed = false, retry = true;
439 	int err = 0;
440 retry:
441 	mutex_lock(&nf_ct_proto_mutex);
442 
443 	switch (nfproto) {
444 	case NFPROTO_IPV4:
445 		cnet->users4++;
446 		if (cnet->users4 > 1)
447 			goto out_unlock;
448 		err = nf_defrag_ipv4_enable(net);
449 		if (err) {
450 			cnet->users4 = 0;
451 			goto out_unlock;
452 		}
453 
454 		err = nf_register_net_hooks(net, ipv4_conntrack_ops,
455 					    ARRAY_SIZE(ipv4_conntrack_ops));
456 		if (err)
457 			cnet->users4 = 0;
458 		else
459 			fixup_needed = true;
460 		break;
461 #if IS_ENABLED(CONFIG_IPV6)
462 	case NFPROTO_IPV6:
463 		cnet->users6++;
464 		if (cnet->users6 > 1)
465 			goto out_unlock;
466 		err = nf_defrag_ipv6_enable(net);
467 		if (err < 0) {
468 			cnet->users6 = 0;
469 			goto out_unlock;
470 		}
471 
472 		err = nf_register_net_hooks(net, ipv6_conntrack_ops,
473 					    ARRAY_SIZE(ipv6_conntrack_ops));
474 		if (err)
475 			cnet->users6 = 0;
476 		else
477 			fixup_needed = true;
478 		break;
479 #endif
480 	case NFPROTO_BRIDGE:
481 		if (!nf_ct_bridge_info) {
482 			if (!retry) {
483 				err = -EPROTO;
484 				goto out_unlock;
485 			}
486 			mutex_unlock(&nf_ct_proto_mutex);
487 			request_module("nf_conntrack_bridge");
488 			retry = false;
489 			goto retry;
490 		}
491 		if (!try_module_get(nf_ct_bridge_info->me)) {
492 			err = -EPROTO;
493 			goto out_unlock;
494 		}
495 		cnet->users_bridge++;
496 		if (cnet->users_bridge > 1)
497 			goto out_unlock;
498 
499 		err = nf_register_net_hooks(net, nf_ct_bridge_info->ops,
500 					    nf_ct_bridge_info->ops_size);
501 		if (err)
502 			cnet->users_bridge = 0;
503 		else
504 			fixup_needed = true;
505 		break;
506 	default:
507 		err = -EPROTO;
508 		break;
509 	}
510  out_unlock:
511 	mutex_unlock(&nf_ct_proto_mutex);
512 
513 	if (fixup_needed) {
514 		struct nf_ct_iter_data iter_data = {
515 			.net	= net,
516 			.data	= (void *)(unsigned long)nfproto,
517 		};
518 		nf_ct_iterate_cleanup_net(nf_ct_tcp_fixup, &iter_data);
519 	}
520 
521 	return err;
522 }
523 
nf_ct_netns_do_put(struct net * net,u8 nfproto)524 static void nf_ct_netns_do_put(struct net *net, u8 nfproto)
525 {
526 	struct nf_conntrack_net *cnet = nf_ct_pernet(net);
527 
528 	mutex_lock(&nf_ct_proto_mutex);
529 	switch (nfproto) {
530 	case NFPROTO_IPV4:
531 		if (cnet->users4 && (--cnet->users4 == 0)) {
532 			nf_unregister_net_hooks(net, ipv4_conntrack_ops,
533 						ARRAY_SIZE(ipv4_conntrack_ops));
534 			nf_defrag_ipv4_disable(net);
535 		}
536 		break;
537 #if IS_ENABLED(CONFIG_IPV6)
538 	case NFPROTO_IPV6:
539 		if (cnet->users6 && (--cnet->users6 == 0)) {
540 			nf_unregister_net_hooks(net, ipv6_conntrack_ops,
541 						ARRAY_SIZE(ipv6_conntrack_ops));
542 			nf_defrag_ipv6_disable(net);
543 		}
544 		break;
545 #endif
546 	case NFPROTO_BRIDGE:
547 		if (!nf_ct_bridge_info)
548 			break;
549 		if (cnet->users_bridge && (--cnet->users_bridge == 0))
550 			nf_unregister_net_hooks(net, nf_ct_bridge_info->ops,
551 						nf_ct_bridge_info->ops_size);
552 
553 		module_put(nf_ct_bridge_info->me);
554 		break;
555 	}
556 	mutex_unlock(&nf_ct_proto_mutex);
557 }
558 
nf_ct_netns_inet_get(struct net * net)559 static int nf_ct_netns_inet_get(struct net *net)
560 {
561 	int err;
562 
563 	err = nf_ct_netns_do_get(net, NFPROTO_IPV4);
564 #if IS_ENABLED(CONFIG_IPV6)
565 	if (err < 0)
566 		goto err1;
567 	err = nf_ct_netns_do_get(net, NFPROTO_IPV6);
568 	if (err < 0)
569 		goto err2;
570 
571 	return err;
572 err2:
573 	nf_ct_netns_put(net, NFPROTO_IPV4);
574 err1:
575 #endif
576 	return err;
577 }
578 
nf_ct_netns_get(struct net * net,u8 nfproto)579 int nf_ct_netns_get(struct net *net, u8 nfproto)
580 {
581 	int err;
582 
583 	switch (nfproto) {
584 	case NFPROTO_INET:
585 		err = nf_ct_netns_inet_get(net);
586 		break;
587 	case NFPROTO_BRIDGE:
588 		err = nf_ct_netns_do_get(net, NFPROTO_BRIDGE);
589 		if (err < 0)
590 			return err;
591 
592 		err = nf_ct_netns_inet_get(net);
593 		if (err < 0) {
594 			nf_ct_netns_put(net, NFPROTO_BRIDGE);
595 			return err;
596 		}
597 		break;
598 	default:
599 		err = nf_ct_netns_do_get(net, nfproto);
600 		break;
601 	}
602 	return err;
603 }
604 EXPORT_SYMBOL_GPL(nf_ct_netns_get);
605 
nf_ct_netns_put(struct net * net,uint8_t nfproto)606 void nf_ct_netns_put(struct net *net, uint8_t nfproto)
607 {
608 	switch (nfproto) {
609 	case NFPROTO_BRIDGE:
610 		nf_ct_netns_do_put(net, NFPROTO_BRIDGE);
611 		fallthrough;
612 	case NFPROTO_INET:
613 		nf_ct_netns_do_put(net, NFPROTO_IPV4);
614 		nf_ct_netns_do_put(net, NFPROTO_IPV6);
615 		break;
616 	default:
617 		nf_ct_netns_do_put(net, nfproto);
618 		break;
619 	}
620 }
621 EXPORT_SYMBOL_GPL(nf_ct_netns_put);
622 
nf_ct_bridge_register(struct nf_ct_bridge_info * info)623 void nf_ct_bridge_register(struct nf_ct_bridge_info *info)
624 {
625 	WARN_ON(nf_ct_bridge_info);
626 	mutex_lock(&nf_ct_proto_mutex);
627 	nf_ct_bridge_info = info;
628 	mutex_unlock(&nf_ct_proto_mutex);
629 }
630 EXPORT_SYMBOL_GPL(nf_ct_bridge_register);
631 
nf_ct_bridge_unregister(struct nf_ct_bridge_info * info)632 void nf_ct_bridge_unregister(struct nf_ct_bridge_info *info)
633 {
634 	WARN_ON(!nf_ct_bridge_info);
635 	mutex_lock(&nf_ct_proto_mutex);
636 	nf_ct_bridge_info = NULL;
637 	mutex_unlock(&nf_ct_proto_mutex);
638 }
639 EXPORT_SYMBOL_GPL(nf_ct_bridge_unregister);
640 
nf_conntrack_proto_init(void)641 int nf_conntrack_proto_init(void)
642 {
643 	int ret;
644 
645 	ret = nf_register_sockopt(&so_getorigdst);
646 	if (ret < 0)
647 		return ret;
648 
649 #if IS_ENABLED(CONFIG_IPV6)
650 	ret = nf_register_sockopt(&so_getorigdst6);
651 	if (ret < 0)
652 		goto cleanup_sockopt;
653 #endif
654 
655 	return ret;
656 
657 #if IS_ENABLED(CONFIG_IPV6)
658 cleanup_sockopt:
659 	nf_unregister_sockopt(&so_getorigdst);
660 #endif
661 	return ret;
662 }
663 
nf_conntrack_proto_fini(void)664 void nf_conntrack_proto_fini(void)
665 {
666 	nf_unregister_sockopt(&so_getorigdst);
667 #if IS_ENABLED(CONFIG_IPV6)
668 	nf_unregister_sockopt(&so_getorigdst6);
669 #endif
670 }
671 
nf_conntrack_proto_pernet_init(struct net * net)672 void nf_conntrack_proto_pernet_init(struct net *net)
673 {
674 	nf_conntrack_generic_init_net(net);
675 	nf_conntrack_udp_init_net(net);
676 	nf_conntrack_tcp_init_net(net);
677 	nf_conntrack_icmp_init_net(net);
678 #if IS_ENABLED(CONFIG_IPV6)
679 	nf_conntrack_icmpv6_init_net(net);
680 #endif
681 #ifdef CONFIG_NF_CT_PROTO_SCTP
682 	nf_conntrack_sctp_init_net(net);
683 #endif
684 #ifdef CONFIG_NF_CT_PROTO_GRE
685 	nf_conntrack_gre_init_net(net);
686 #endif
687 }
688 
689 module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
690 		  &nf_conntrack_htable_size, 0600);
691 
692 MODULE_ALIAS("ip_conntrack");
693 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET));
694 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
695 MODULE_LICENSE("GPL");
696 MODULE_DESCRIPTION("IPv4 and IPv6 connection tracking");
697