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_DCCP
104 	case IPPROTO_DCCP: return &nf_conntrack_l4proto_dccp;
105 #endif
106 #ifdef CONFIG_NF_CT_PROTO_SCTP
107 	case IPPROTO_SCTP: return &nf_conntrack_l4proto_sctp;
108 #endif
109 #ifdef CONFIG_NF_CT_PROTO_UDPLITE
110 	case IPPROTO_UDPLITE: return &nf_conntrack_l4proto_udplite;
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 
nf_confirm(struct sk_buff * skb,unsigned int protoff,struct nf_conn * ct,enum ip_conntrack_info ctinfo)124 unsigned int nf_confirm(struct sk_buff *skb, unsigned int protoff,
125 			struct nf_conn *ct, enum ip_conntrack_info ctinfo)
126 {
127 	const struct nf_conn_help *help;
128 
129 	help = nfct_help(ct);
130 	if (help) {
131 		const struct nf_conntrack_helper *helper;
132 		int ret;
133 
134 		/* rcu_read_lock()ed by nf_hook_thresh */
135 		helper = rcu_dereference(help->helper);
136 		if (helper) {
137 			ret = helper->help(skb,
138 					   protoff,
139 					   ct, ctinfo);
140 			if (ret != NF_ACCEPT)
141 				return ret;
142 		}
143 	}
144 
145 	if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
146 	    !nf_is_loopback_packet(skb)) {
147 		if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
148 			NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
149 			return NF_DROP;
150 		}
151 	}
152 
153 	/* We've seen it coming out the other side: confirm it */
154 	return nf_conntrack_confirm(skb);
155 }
156 EXPORT_SYMBOL_GPL(nf_confirm);
157 
ipv4_confirm(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)158 static unsigned int ipv4_confirm(void *priv,
159 				 struct sk_buff *skb,
160 				 const struct nf_hook_state *state)
161 {
162 	enum ip_conntrack_info ctinfo;
163 	struct nf_conn *ct;
164 
165 	ct = nf_ct_get(skb, &ctinfo);
166 	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
167 		return nf_conntrack_confirm(skb);
168 
169 	return nf_confirm(skb,
170 			  skb_network_offset(skb) + ip_hdrlen(skb),
171 			  ct, ctinfo);
172 }
173 
ipv4_conntrack_in(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)174 static unsigned int ipv4_conntrack_in(void *priv,
175 				      struct sk_buff *skb,
176 				      const struct nf_hook_state *state)
177 {
178 	return nf_conntrack_in(skb, state);
179 }
180 
ipv4_conntrack_local(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)181 static unsigned int ipv4_conntrack_local(void *priv,
182 					 struct sk_buff *skb,
183 					 const struct nf_hook_state *state)
184 {
185 	if (ip_is_fragment(ip_hdr(skb))) { /* IP_NODEFRAG setsockopt set */
186 		enum ip_conntrack_info ctinfo;
187 		struct nf_conn *tmpl;
188 
189 		tmpl = nf_ct_get(skb, &ctinfo);
190 		if (tmpl && nf_ct_is_template(tmpl)) {
191 			/* when skipping ct, clear templates to avoid fooling
192 			 * later targets/matches
193 			 */
194 			skb->_nfct = 0;
195 			nf_ct_put(tmpl);
196 		}
197 		return NF_ACCEPT;
198 	}
199 
200 	return nf_conntrack_in(skb, state);
201 }
202 
203 /* Connection tracking may drop packets, but never alters them, so
204  * make it the first hook.
205  */
206 static const struct nf_hook_ops ipv4_conntrack_ops[] = {
207 	{
208 		.hook		= ipv4_conntrack_in,
209 		.pf		= NFPROTO_IPV4,
210 		.hooknum	= NF_INET_PRE_ROUTING,
211 		.priority	= NF_IP_PRI_CONNTRACK,
212 	},
213 	{
214 		.hook		= ipv4_conntrack_local,
215 		.pf		= NFPROTO_IPV4,
216 		.hooknum	= NF_INET_LOCAL_OUT,
217 		.priority	= NF_IP_PRI_CONNTRACK,
218 	},
219 	{
220 		.hook		= ipv4_confirm,
221 		.pf		= NFPROTO_IPV4,
222 		.hooknum	= NF_INET_POST_ROUTING,
223 		.priority	= NF_IP_PRI_CONNTRACK_CONFIRM,
224 	},
225 	{
226 		.hook		= ipv4_confirm,
227 		.pf		= NFPROTO_IPV4,
228 		.hooknum	= NF_INET_LOCAL_IN,
229 		.priority	= NF_IP_PRI_CONNTRACK_CONFIRM,
230 	},
231 };
232 
233 /* Fast function for those who don't want to parse /proc (and I don't
234  * blame them).
235  * Reversing the socket's dst/src point of view gives us the reply
236  * mapping.
237  */
238 static int
getorigdst(struct sock * sk,int optval,void __user * user,int * len)239 getorigdst(struct sock *sk, int optval, void __user *user, int *len)
240 {
241 	const struct inet_sock *inet = inet_sk(sk);
242 	const struct nf_conntrack_tuple_hash *h;
243 	struct nf_conntrack_tuple tuple;
244 
245 	memset(&tuple, 0, sizeof(tuple));
246 
247 	lock_sock(sk);
248 	tuple.src.u3.ip = inet->inet_rcv_saddr;
249 	tuple.src.u.tcp.port = inet->inet_sport;
250 	tuple.dst.u3.ip = inet->inet_daddr;
251 	tuple.dst.u.tcp.port = inet->inet_dport;
252 	tuple.src.l3num = PF_INET;
253 	tuple.dst.protonum = sk->sk_protocol;
254 	release_sock(sk);
255 
256 	/* We only do TCP and SCTP at the moment: is there a better way? */
257 	if (tuple.dst.protonum != IPPROTO_TCP &&
258 	    tuple.dst.protonum != IPPROTO_SCTP) {
259 		pr_debug("SO_ORIGINAL_DST: Not a TCP/SCTP socket\n");
260 		return -ENOPROTOOPT;
261 	}
262 
263 	if ((unsigned int)*len < sizeof(struct sockaddr_in)) {
264 		pr_debug("SO_ORIGINAL_DST: len %d not %zu\n",
265 			 *len, sizeof(struct sockaddr_in));
266 		return -EINVAL;
267 	}
268 
269 	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
270 	if (h) {
271 		struct sockaddr_in sin;
272 		struct nf_conn *ct = nf_ct_tuplehash_to_ctrack(h);
273 
274 		sin.sin_family = AF_INET;
275 		sin.sin_port = ct->tuplehash[IP_CT_DIR_ORIGINAL]
276 			.tuple.dst.u.tcp.port;
277 		sin.sin_addr.s_addr = ct->tuplehash[IP_CT_DIR_ORIGINAL]
278 			.tuple.dst.u3.ip;
279 		memset(sin.sin_zero, 0, sizeof(sin.sin_zero));
280 
281 		pr_debug("SO_ORIGINAL_DST: %pI4 %u\n",
282 			 &sin.sin_addr.s_addr, ntohs(sin.sin_port));
283 		nf_ct_put(ct);
284 		if (copy_to_user(user, &sin, sizeof(sin)) != 0)
285 			return -EFAULT;
286 		else
287 			return 0;
288 	}
289 	pr_debug("SO_ORIGINAL_DST: Can't find %pI4/%u-%pI4/%u.\n",
290 		 &tuple.src.u3.ip, ntohs(tuple.src.u.tcp.port),
291 		 &tuple.dst.u3.ip, ntohs(tuple.dst.u.tcp.port));
292 	return -ENOENT;
293 }
294 
295 static struct nf_sockopt_ops so_getorigdst = {
296 	.pf		= PF_INET,
297 	.get_optmin	= SO_ORIGINAL_DST,
298 	.get_optmax	= SO_ORIGINAL_DST + 1,
299 	.get		= getorigdst,
300 	.owner		= THIS_MODULE,
301 };
302 
303 #if IS_ENABLED(CONFIG_IPV6)
304 static int
ipv6_getorigdst(struct sock * sk,int optval,void __user * user,int * len)305 ipv6_getorigdst(struct sock *sk, int optval, void __user *user, int *len)
306 {
307 	struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
308 	const struct ipv6_pinfo *inet6 = inet6_sk(sk);
309 	const struct inet_sock *inet = inet_sk(sk);
310 	const struct nf_conntrack_tuple_hash *h;
311 	struct sockaddr_in6 sin6;
312 	struct nf_conn *ct;
313 	__be32 flow_label;
314 	int bound_dev_if;
315 
316 	lock_sock(sk);
317 	tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
318 	tuple.src.u.tcp.port = inet->inet_sport;
319 	tuple.dst.u3.in6 = sk->sk_v6_daddr;
320 	tuple.dst.u.tcp.port = inet->inet_dport;
321 	tuple.dst.protonum = sk->sk_protocol;
322 	bound_dev_if = sk->sk_bound_dev_if;
323 	flow_label = inet6->flow_label;
324 	release_sock(sk);
325 
326 	if (tuple.dst.protonum != IPPROTO_TCP &&
327 	    tuple.dst.protonum != IPPROTO_SCTP)
328 		return -ENOPROTOOPT;
329 
330 	if (*len < 0 || (unsigned int)*len < sizeof(sin6))
331 		return -EINVAL;
332 
333 	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
334 	if (!h) {
335 		pr_debug("IP6T_SO_ORIGINAL_DST: Can't find %pI6c/%u-%pI6c/%u.\n",
336 			 &tuple.src.u3.ip6, ntohs(tuple.src.u.tcp.port),
337 			 &tuple.dst.u3.ip6, ntohs(tuple.dst.u.tcp.port));
338 		return -ENOENT;
339 	}
340 
341 	ct = nf_ct_tuplehash_to_ctrack(h);
342 
343 	sin6.sin6_family = AF_INET6;
344 	sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
345 	sin6.sin6_flowinfo = flow_label & IPV6_FLOWINFO_MASK;
346 	memcpy(&sin6.sin6_addr,
347 	       &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
348 	       sizeof(sin6.sin6_addr));
349 
350 	nf_ct_put(ct);
351 	sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr, bound_dev_if);
352 	return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
353 }
354 
355 static struct nf_sockopt_ops so_getorigdst6 = {
356 	.pf		= NFPROTO_IPV6,
357 	.get_optmin	= IP6T_SO_ORIGINAL_DST,
358 	.get_optmax	= IP6T_SO_ORIGINAL_DST + 1,
359 	.get		= ipv6_getorigdst,
360 	.owner		= THIS_MODULE,
361 };
362 
ipv6_confirm(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)363 static unsigned int ipv6_confirm(void *priv,
364 				 struct sk_buff *skb,
365 				 const struct nf_hook_state *state)
366 {
367 	struct nf_conn *ct;
368 	enum ip_conntrack_info ctinfo;
369 	unsigned char pnum = ipv6_hdr(skb)->nexthdr;
370 	__be16 frag_off;
371 	int protoff;
372 
373 	ct = nf_ct_get(skb, &ctinfo);
374 	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
375 		return nf_conntrack_confirm(skb);
376 
377 	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum,
378 				   &frag_off);
379 	if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
380 		pr_debug("proto header not found\n");
381 		return nf_conntrack_confirm(skb);
382 	}
383 
384 	return nf_confirm(skb, protoff, ct, ctinfo);
385 }
386 
ipv6_conntrack_in(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)387 static unsigned int ipv6_conntrack_in(void *priv,
388 				      struct sk_buff *skb,
389 				      const struct nf_hook_state *state)
390 {
391 	return nf_conntrack_in(skb, state);
392 }
393 
ipv6_conntrack_local(void * priv,struct sk_buff * skb,const struct nf_hook_state * state)394 static unsigned int ipv6_conntrack_local(void *priv,
395 					 struct sk_buff *skb,
396 					 const struct nf_hook_state *state)
397 {
398 	return nf_conntrack_in(skb, state);
399 }
400 
401 static const struct nf_hook_ops ipv6_conntrack_ops[] = {
402 	{
403 		.hook		= ipv6_conntrack_in,
404 		.pf		= NFPROTO_IPV6,
405 		.hooknum	= NF_INET_PRE_ROUTING,
406 		.priority	= NF_IP6_PRI_CONNTRACK,
407 	},
408 	{
409 		.hook		= ipv6_conntrack_local,
410 		.pf		= NFPROTO_IPV6,
411 		.hooknum	= NF_INET_LOCAL_OUT,
412 		.priority	= NF_IP6_PRI_CONNTRACK,
413 	},
414 	{
415 		.hook		= ipv6_confirm,
416 		.pf		= NFPROTO_IPV6,
417 		.hooknum	= NF_INET_POST_ROUTING,
418 		.priority	= NF_IP6_PRI_LAST,
419 	},
420 	{
421 		.hook		= ipv6_confirm,
422 		.pf		= NFPROTO_IPV6,
423 		.hooknum	= NF_INET_LOCAL_IN,
424 		.priority	= NF_IP6_PRI_LAST - 1,
425 	},
426 };
427 #endif
428 
nf_ct_tcp_fixup(struct nf_conn * ct,void * _nfproto)429 static int nf_ct_tcp_fixup(struct nf_conn *ct, void *_nfproto)
430 {
431 	u8 nfproto = (unsigned long)_nfproto;
432 
433 	if (nf_ct_l3num(ct) != nfproto)
434 		return 0;
435 
436 	if (nf_ct_protonum(ct) == IPPROTO_TCP &&
437 	    ct->proto.tcp.state == TCP_CONNTRACK_ESTABLISHED) {
438 		ct->proto.tcp.seen[0].td_maxwin = 0;
439 		ct->proto.tcp.seen[1].td_maxwin = 0;
440 	}
441 
442 	return 0;
443 }
444 
445 static struct nf_ct_bridge_info *nf_ct_bridge_info;
446 
nf_ct_netns_do_get(struct net * net,u8 nfproto)447 static int nf_ct_netns_do_get(struct net *net, u8 nfproto)
448 {
449 	struct nf_conntrack_net *cnet = nf_ct_pernet(net);
450 	bool fixup_needed = false, retry = true;
451 	int err = 0;
452 retry:
453 	mutex_lock(&nf_ct_proto_mutex);
454 
455 	switch (nfproto) {
456 	case NFPROTO_IPV4:
457 		cnet->users4++;
458 		if (cnet->users4 > 1)
459 			goto out_unlock;
460 		err = nf_defrag_ipv4_enable(net);
461 		if (err) {
462 			cnet->users4 = 0;
463 			goto out_unlock;
464 		}
465 
466 		err = nf_register_net_hooks(net, ipv4_conntrack_ops,
467 					    ARRAY_SIZE(ipv4_conntrack_ops));
468 		if (err)
469 			cnet->users4 = 0;
470 		else
471 			fixup_needed = true;
472 		break;
473 #if IS_ENABLED(CONFIG_IPV6)
474 	case NFPROTO_IPV6:
475 		cnet->users6++;
476 		if (cnet->users6 > 1)
477 			goto out_unlock;
478 		err = nf_defrag_ipv6_enable(net);
479 		if (err < 0) {
480 			cnet->users6 = 0;
481 			goto out_unlock;
482 		}
483 
484 		err = nf_register_net_hooks(net, ipv6_conntrack_ops,
485 					    ARRAY_SIZE(ipv6_conntrack_ops));
486 		if (err)
487 			cnet->users6 = 0;
488 		else
489 			fixup_needed = true;
490 		break;
491 #endif
492 	case NFPROTO_BRIDGE:
493 		if (!nf_ct_bridge_info) {
494 			if (!retry) {
495 				err = -EPROTO;
496 				goto out_unlock;
497 			}
498 			mutex_unlock(&nf_ct_proto_mutex);
499 			request_module("nf_conntrack_bridge");
500 			retry = false;
501 			goto retry;
502 		}
503 		if (!try_module_get(nf_ct_bridge_info->me)) {
504 			err = -EPROTO;
505 			goto out_unlock;
506 		}
507 		cnet->users_bridge++;
508 		if (cnet->users_bridge > 1)
509 			goto out_unlock;
510 
511 		err = nf_register_net_hooks(net, nf_ct_bridge_info->ops,
512 					    nf_ct_bridge_info->ops_size);
513 		if (err)
514 			cnet->users_bridge = 0;
515 		else
516 			fixup_needed = true;
517 		break;
518 	default:
519 		err = -EPROTO;
520 		break;
521 	}
522  out_unlock:
523 	mutex_unlock(&nf_ct_proto_mutex);
524 
525 	if (fixup_needed)
526 		nf_ct_iterate_cleanup_net(net, nf_ct_tcp_fixup,
527 					  (void *)(unsigned long)nfproto, 0, 0);
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_DCCP
690 	nf_conntrack_dccp_init_net(net);
691 #endif
692 #ifdef CONFIG_NF_CT_PROTO_SCTP
693 	nf_conntrack_sctp_init_net(net);
694 #endif
695 #ifdef CONFIG_NF_CT_PROTO_GRE
696 	nf_conntrack_gre_init_net(net);
697 #endif
698 }
699 
700 module_param_call(hashsize, nf_conntrack_set_hashsize, param_get_uint,
701 		  &nf_conntrack_htable_size, 0600);
702 
703 MODULE_ALIAS("ip_conntrack");
704 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET));
705 MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
706 MODULE_LICENSE("GPL");
707