1 /* Connection tracking via netlink socket. Allows for user space
2  * protocol helpers and general trouble making from userspace.
3  *
4  * (C) 2001 by Jay Schulist <jschlst@samba.org>
5  * (C) 2002-2006 by Harald Welte <laforge@gnumonks.org>
6  * (C) 2003 by Patrick Mchardy <kaber@trash.net>
7  * (C) 2005-2012 by Pablo Neira Ayuso <pablo@netfilter.org>
8  *
9  * Initial connection tracking via netlink development funded and
10  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
11  *
12  * Further development of this code funded by Astaro AG (http://www.astaro.com)
13  *
14  * This software may be used and distributed according to the terms
15  * of the GNU General Public License, incorporated herein by reference.
16  */
17 
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/kernel.h>
21 #include <linux/rculist.h>
22 #include <linux/rculist_nulls.h>
23 #include <linux/types.h>
24 #include <linux/timer.h>
25 #include <linux/security.h>
26 #include <linux/skbuff.h>
27 #include <linux/errno.h>
28 #include <linux/netlink.h>
29 #include <linux/spinlock.h>
30 #include <linux/interrupt.h>
31 #include <linux/slab.h>
32 #include <linux/siphash.h>
33 
34 #include <linux/netfilter.h>
35 #include <net/netlink.h>
36 #include <net/sock.h>
37 #include <net/netfilter/nf_conntrack.h>
38 #include <net/netfilter/nf_conntrack_core.h>
39 #include <net/netfilter/nf_conntrack_expect.h>
40 #include <net/netfilter/nf_conntrack_helper.h>
41 #include <net/netfilter/nf_conntrack_seqadj.h>
42 #include <net/netfilter/nf_conntrack_l4proto.h>
43 #include <net/netfilter/nf_conntrack_tuple.h>
44 #include <net/netfilter/nf_conntrack_acct.h>
45 #include <net/netfilter/nf_conntrack_zones.h>
46 #include <net/netfilter/nf_conntrack_timestamp.h>
47 #include <net/netfilter/nf_conntrack_labels.h>
48 #include <net/netfilter/nf_conntrack_synproxy.h>
49 #if IS_ENABLED(CONFIG_NF_NAT)
50 #include <net/netfilter/nf_nat.h>
51 #include <net/netfilter/nf_nat_helper.h>
52 #endif
53 
54 #include <linux/netfilter/nfnetlink.h>
55 #include <linux/netfilter/nfnetlink_conntrack.h>
56 
57 #include "nf_internals.h"
58 
59 MODULE_LICENSE("GPL");
60 MODULE_DESCRIPTION("List and change connection tracking table");
61 
62 struct ctnetlink_list_dump_ctx {
63 	struct nf_conn *last;
64 	unsigned int cpu;
65 	bool done;
66 };
67 
ctnetlink_dump_tuples_proto(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_l4proto * l4proto)68 static int ctnetlink_dump_tuples_proto(struct sk_buff *skb,
69 				const struct nf_conntrack_tuple *tuple,
70 				const struct nf_conntrack_l4proto *l4proto)
71 {
72 	int ret = 0;
73 	struct nlattr *nest_parms;
74 
75 	nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO);
76 	if (!nest_parms)
77 		goto nla_put_failure;
78 	if (nla_put_u8(skb, CTA_PROTO_NUM, tuple->dst.protonum))
79 		goto nla_put_failure;
80 
81 	if (likely(l4proto->tuple_to_nlattr))
82 		ret = l4proto->tuple_to_nlattr(skb, tuple);
83 
84 	nla_nest_end(skb, nest_parms);
85 
86 	return ret;
87 
88 nla_put_failure:
89 	return -1;
90 }
91 
ipv4_tuple_to_nlattr(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)92 static int ipv4_tuple_to_nlattr(struct sk_buff *skb,
93 				const struct nf_conntrack_tuple *tuple)
94 {
95 	if (nla_put_in_addr(skb, CTA_IP_V4_SRC, tuple->src.u3.ip) ||
96 	    nla_put_in_addr(skb, CTA_IP_V4_DST, tuple->dst.u3.ip))
97 		return -EMSGSIZE;
98 	return 0;
99 }
100 
ipv6_tuple_to_nlattr(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)101 static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
102 				const struct nf_conntrack_tuple *tuple)
103 {
104 	if (nla_put_in6_addr(skb, CTA_IP_V6_SRC, &tuple->src.u3.in6) ||
105 	    nla_put_in6_addr(skb, CTA_IP_V6_DST, &tuple->dst.u3.in6))
106 		return -EMSGSIZE;
107 	return 0;
108 }
109 
ctnetlink_dump_tuples_ip(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)110 static int ctnetlink_dump_tuples_ip(struct sk_buff *skb,
111 				    const struct nf_conntrack_tuple *tuple)
112 {
113 	int ret = 0;
114 	struct nlattr *nest_parms;
115 
116 	nest_parms = nla_nest_start(skb, CTA_TUPLE_IP);
117 	if (!nest_parms)
118 		goto nla_put_failure;
119 
120 	switch (tuple->src.l3num) {
121 	case NFPROTO_IPV4:
122 		ret = ipv4_tuple_to_nlattr(skb, tuple);
123 		break;
124 	case NFPROTO_IPV6:
125 		ret = ipv6_tuple_to_nlattr(skb, tuple);
126 		break;
127 	}
128 
129 	nla_nest_end(skb, nest_parms);
130 
131 	return ret;
132 
133 nla_put_failure:
134 	return -1;
135 }
136 
ctnetlink_dump_tuples(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)137 static int ctnetlink_dump_tuples(struct sk_buff *skb,
138 				 const struct nf_conntrack_tuple *tuple)
139 {
140 	const struct nf_conntrack_l4proto *l4proto;
141 	int ret;
142 
143 	rcu_read_lock();
144 	ret = ctnetlink_dump_tuples_ip(skb, tuple);
145 
146 	if (ret >= 0) {
147 		l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
148 		ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
149 	}
150 	rcu_read_unlock();
151 	return ret;
152 }
153 
ctnetlink_dump_zone_id(struct sk_buff * skb,int attrtype,const struct nf_conntrack_zone * zone,int dir)154 static int ctnetlink_dump_zone_id(struct sk_buff *skb, int attrtype,
155 				  const struct nf_conntrack_zone *zone, int dir)
156 {
157 	if (zone->id == NF_CT_DEFAULT_ZONE_ID || zone->dir != dir)
158 		return 0;
159 	if (nla_put_be16(skb, attrtype, htons(zone->id)))
160 		goto nla_put_failure;
161 	return 0;
162 
163 nla_put_failure:
164 	return -1;
165 }
166 
ctnetlink_dump_status(struct sk_buff * skb,const struct nf_conn * ct)167 static int ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
168 {
169 	if (nla_put_be32(skb, CTA_STATUS, htonl(ct->status)))
170 		goto nla_put_failure;
171 	return 0;
172 
173 nla_put_failure:
174 	return -1;
175 }
176 
ctnetlink_dump_timeout(struct sk_buff * skb,const struct nf_conn * ct,bool skip_zero)177 static int ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct,
178 				  bool skip_zero)
179 {
180 	long timeout;
181 
182 	if (nf_ct_is_confirmed(ct))
183 		timeout = nf_ct_expires(ct) / HZ;
184 	else
185 		timeout = ct->timeout / HZ;
186 
187 	if (skip_zero && timeout == 0)
188 		return 0;
189 
190 	if (nla_put_be32(skb, CTA_TIMEOUT, htonl(timeout)))
191 		goto nla_put_failure;
192 	return 0;
193 
194 nla_put_failure:
195 	return -1;
196 }
197 
ctnetlink_dump_protoinfo(struct sk_buff * skb,struct nf_conn * ct,bool destroy)198 static int ctnetlink_dump_protoinfo(struct sk_buff *skb, struct nf_conn *ct,
199 				    bool destroy)
200 {
201 	const struct nf_conntrack_l4proto *l4proto;
202 	struct nlattr *nest_proto;
203 	int ret;
204 
205 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
206 	if (!l4proto->to_nlattr)
207 		return 0;
208 
209 	nest_proto = nla_nest_start(skb, CTA_PROTOINFO);
210 	if (!nest_proto)
211 		goto nla_put_failure;
212 
213 	ret = l4proto->to_nlattr(skb, nest_proto, ct, destroy);
214 
215 	nla_nest_end(skb, nest_proto);
216 
217 	return ret;
218 
219 nla_put_failure:
220 	return -1;
221 }
222 
ctnetlink_dump_helpinfo(struct sk_buff * skb,const struct nf_conn * ct)223 static int ctnetlink_dump_helpinfo(struct sk_buff *skb,
224 				   const struct nf_conn *ct)
225 {
226 	struct nlattr *nest_helper;
227 	const struct nf_conn_help *help = nfct_help(ct);
228 	struct nf_conntrack_helper *helper;
229 
230 	if (!help)
231 		return 0;
232 
233 	rcu_read_lock();
234 	helper = rcu_dereference(help->helper);
235 	if (!helper)
236 		goto out;
237 
238 	nest_helper = nla_nest_start(skb, CTA_HELP);
239 	if (!nest_helper)
240 		goto nla_put_failure;
241 	if (nla_put_string(skb, CTA_HELP_NAME, helper->name))
242 		goto nla_put_failure;
243 
244 	if (helper->to_nlattr)
245 		helper->to_nlattr(skb, ct);
246 
247 	nla_nest_end(skb, nest_helper);
248 out:
249 	rcu_read_unlock();
250 	return 0;
251 
252 nla_put_failure:
253 	rcu_read_unlock();
254 	return -1;
255 }
256 
257 static int
dump_counters(struct sk_buff * skb,struct nf_conn_acct * acct,enum ip_conntrack_dir dir,int type)258 dump_counters(struct sk_buff *skb, struct nf_conn_acct *acct,
259 	      enum ip_conntrack_dir dir, int type)
260 {
261 	enum ctattr_type attr = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
262 	struct nf_conn_counter *counter = acct->counter;
263 	struct nlattr *nest_count;
264 	u64 pkts, bytes;
265 
266 	if (type == IPCTNL_MSG_CT_GET_CTRZERO) {
267 		pkts = atomic64_xchg(&counter[dir].packets, 0);
268 		bytes = atomic64_xchg(&counter[dir].bytes, 0);
269 	} else {
270 		pkts = atomic64_read(&counter[dir].packets);
271 		bytes = atomic64_read(&counter[dir].bytes);
272 	}
273 
274 	nest_count = nla_nest_start(skb, attr);
275 	if (!nest_count)
276 		goto nla_put_failure;
277 
278 	if (nla_put_be64(skb, CTA_COUNTERS_PACKETS, cpu_to_be64(pkts),
279 			 CTA_COUNTERS_PAD) ||
280 	    nla_put_be64(skb, CTA_COUNTERS_BYTES, cpu_to_be64(bytes),
281 			 CTA_COUNTERS_PAD))
282 		goto nla_put_failure;
283 
284 	nla_nest_end(skb, nest_count);
285 
286 	return 0;
287 
288 nla_put_failure:
289 	return -1;
290 }
291 
292 static int
ctnetlink_dump_acct(struct sk_buff * skb,const struct nf_conn * ct,int type)293 ctnetlink_dump_acct(struct sk_buff *skb, const struct nf_conn *ct, int type)
294 {
295 	struct nf_conn_acct *acct = nf_conn_acct_find(ct);
296 
297 	if (!acct)
298 		return 0;
299 
300 	if (dump_counters(skb, acct, IP_CT_DIR_ORIGINAL, type) < 0)
301 		return -1;
302 	if (dump_counters(skb, acct, IP_CT_DIR_REPLY, type) < 0)
303 		return -1;
304 
305 	return 0;
306 }
307 
308 static int
ctnetlink_dump_timestamp(struct sk_buff * skb,const struct nf_conn * ct)309 ctnetlink_dump_timestamp(struct sk_buff *skb, const struct nf_conn *ct)
310 {
311 	struct nlattr *nest_count;
312 	const struct nf_conn_tstamp *tstamp;
313 
314 	tstamp = nf_conn_tstamp_find(ct);
315 	if (!tstamp)
316 		return 0;
317 
318 	nest_count = nla_nest_start(skb, CTA_TIMESTAMP);
319 	if (!nest_count)
320 		goto nla_put_failure;
321 
322 	if (nla_put_be64(skb, CTA_TIMESTAMP_START, cpu_to_be64(tstamp->start),
323 			 CTA_TIMESTAMP_PAD) ||
324 	    (tstamp->stop != 0 && nla_put_be64(skb, CTA_TIMESTAMP_STOP,
325 					       cpu_to_be64(tstamp->stop),
326 					       CTA_TIMESTAMP_PAD)))
327 		goto nla_put_failure;
328 	nla_nest_end(skb, nest_count);
329 
330 	return 0;
331 
332 nla_put_failure:
333 	return -1;
334 }
335 
336 #ifdef CONFIG_NF_CONNTRACK_MARK
ctnetlink_dump_mark(struct sk_buff * skb,const struct nf_conn * ct,bool dump)337 static int ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct,
338 			       bool dump)
339 {
340 	u32 mark = READ_ONCE(ct->mark);
341 
342 	if (!mark && !dump)
343 		return 0;
344 
345 	if (nla_put_be32(skb, CTA_MARK, htonl(mark)))
346 		goto nla_put_failure;
347 	return 0;
348 
349 nla_put_failure:
350 	return -1;
351 }
352 #else
353 #define ctnetlink_dump_mark(a, b, c) (0)
354 #endif
355 
356 #ifdef CONFIG_NF_CONNTRACK_SECMARK
ctnetlink_dump_secctx(struct sk_buff * skb,const struct nf_conn * ct)357 static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
358 {
359 	struct nlattr *nest_secctx;
360 	int len, ret;
361 	char *secctx;
362 
363 	ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
364 	if (ret)
365 		return 0;
366 
367 	ret = -1;
368 	nest_secctx = nla_nest_start(skb, CTA_SECCTX);
369 	if (!nest_secctx)
370 		goto nla_put_failure;
371 
372 	if (nla_put_string(skb, CTA_SECCTX_NAME, secctx))
373 		goto nla_put_failure;
374 	nla_nest_end(skb, nest_secctx);
375 
376 	ret = 0;
377 nla_put_failure:
378 	security_release_secctx(secctx, len);
379 	return ret;
380 }
381 #else
382 #define ctnetlink_dump_secctx(a, b) (0)
383 #endif
384 
385 #ifdef CONFIG_NF_CONNTRACK_EVENTS
ctnetlink_label_size(const struct nf_conn * ct)386 static inline int ctnetlink_label_size(const struct nf_conn *ct)
387 {
388 	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
389 
390 	if (!labels)
391 		return 0;
392 	return nla_total_size(sizeof(labels->bits));
393 }
394 #endif
395 
396 static int
ctnetlink_dump_labels(struct sk_buff * skb,const struct nf_conn * ct)397 ctnetlink_dump_labels(struct sk_buff *skb, const struct nf_conn *ct)
398 {
399 	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
400 	unsigned int i;
401 
402 	if (!labels)
403 		return 0;
404 
405 	i = 0;
406 	do {
407 		if (labels->bits[i] != 0)
408 			return nla_put(skb, CTA_LABELS, sizeof(labels->bits),
409 				       labels->bits);
410 		i++;
411 	} while (i < ARRAY_SIZE(labels->bits));
412 
413 	return 0;
414 }
415 
416 #define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
417 
ctnetlink_dump_master(struct sk_buff * skb,const struct nf_conn * ct)418 static int ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
419 {
420 	struct nlattr *nest_parms;
421 
422 	if (!(ct->status & IPS_EXPECTED))
423 		return 0;
424 
425 	nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER);
426 	if (!nest_parms)
427 		goto nla_put_failure;
428 	if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
429 		goto nla_put_failure;
430 	nla_nest_end(skb, nest_parms);
431 
432 	return 0;
433 
434 nla_put_failure:
435 	return -1;
436 }
437 
438 static int
dump_ct_seq_adj(struct sk_buff * skb,const struct nf_ct_seqadj * seq,int type)439 dump_ct_seq_adj(struct sk_buff *skb, const struct nf_ct_seqadj *seq, int type)
440 {
441 	struct nlattr *nest_parms;
442 
443 	nest_parms = nla_nest_start(skb, type);
444 	if (!nest_parms)
445 		goto nla_put_failure;
446 
447 	if (nla_put_be32(skb, CTA_SEQADJ_CORRECTION_POS,
448 			 htonl(seq->correction_pos)) ||
449 	    nla_put_be32(skb, CTA_SEQADJ_OFFSET_BEFORE,
450 			 htonl(seq->offset_before)) ||
451 	    nla_put_be32(skb, CTA_SEQADJ_OFFSET_AFTER,
452 			 htonl(seq->offset_after)))
453 		goto nla_put_failure;
454 
455 	nla_nest_end(skb, nest_parms);
456 
457 	return 0;
458 
459 nla_put_failure:
460 	return -1;
461 }
462 
ctnetlink_dump_ct_seq_adj(struct sk_buff * skb,struct nf_conn * ct)463 static int ctnetlink_dump_ct_seq_adj(struct sk_buff *skb, struct nf_conn *ct)
464 {
465 	struct nf_conn_seqadj *seqadj = nfct_seqadj(ct);
466 	struct nf_ct_seqadj *seq;
467 
468 	if (!(ct->status & IPS_SEQ_ADJUST) || !seqadj)
469 		return 0;
470 
471 	spin_lock_bh(&ct->lock);
472 	seq = &seqadj->seq[IP_CT_DIR_ORIGINAL];
473 	if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_ORIG) == -1)
474 		goto err;
475 
476 	seq = &seqadj->seq[IP_CT_DIR_REPLY];
477 	if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_REPLY) == -1)
478 		goto err;
479 
480 	spin_unlock_bh(&ct->lock);
481 	return 0;
482 err:
483 	spin_unlock_bh(&ct->lock);
484 	return -1;
485 }
486 
ctnetlink_dump_ct_synproxy(struct sk_buff * skb,struct nf_conn * ct)487 static int ctnetlink_dump_ct_synproxy(struct sk_buff *skb, struct nf_conn *ct)
488 {
489 	struct nf_conn_synproxy *synproxy = nfct_synproxy(ct);
490 	struct nlattr *nest_parms;
491 
492 	if (!synproxy)
493 		return 0;
494 
495 	nest_parms = nla_nest_start(skb, CTA_SYNPROXY);
496 	if (!nest_parms)
497 		goto nla_put_failure;
498 
499 	if (nla_put_be32(skb, CTA_SYNPROXY_ISN, htonl(synproxy->isn)) ||
500 	    nla_put_be32(skb, CTA_SYNPROXY_ITS, htonl(synproxy->its)) ||
501 	    nla_put_be32(skb, CTA_SYNPROXY_TSOFF, htonl(synproxy->tsoff)))
502 		goto nla_put_failure;
503 
504 	nla_nest_end(skb, nest_parms);
505 
506 	return 0;
507 
508 nla_put_failure:
509 	return -1;
510 }
511 
ctnetlink_dump_id(struct sk_buff * skb,const struct nf_conn * ct)512 static int ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
513 {
514 	__be32 id = (__force __be32)nf_ct_get_id(ct);
515 
516 	if (nla_put_be32(skb, CTA_ID, id))
517 		goto nla_put_failure;
518 	return 0;
519 
520 nla_put_failure:
521 	return -1;
522 }
523 
ctnetlink_dump_use(struct sk_buff * skb,const struct nf_conn * ct)524 static int ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
525 {
526 	if (nla_put_be32(skb, CTA_USE, htonl(refcount_read(&ct->ct_general.use))))
527 		goto nla_put_failure;
528 	return 0;
529 
530 nla_put_failure:
531 	return -1;
532 }
533 
534 /* all these functions access ct->ext. Caller must either hold a reference
535  * on ct or prevent its deletion by holding either the bucket spinlock or
536  * pcpu dying list lock.
537  */
ctnetlink_dump_extinfo(struct sk_buff * skb,struct nf_conn * ct,u32 type)538 static int ctnetlink_dump_extinfo(struct sk_buff *skb,
539 				  struct nf_conn *ct, u32 type)
540 {
541 	if (ctnetlink_dump_acct(skb, ct, type) < 0 ||
542 	    ctnetlink_dump_timestamp(skb, ct) < 0 ||
543 	    ctnetlink_dump_helpinfo(skb, ct) < 0 ||
544 	    ctnetlink_dump_labels(skb, ct) < 0 ||
545 	    ctnetlink_dump_ct_seq_adj(skb, ct) < 0 ||
546 	    ctnetlink_dump_ct_synproxy(skb, ct) < 0)
547 		return -1;
548 
549 	return 0;
550 }
551 
ctnetlink_dump_info(struct sk_buff * skb,struct nf_conn * ct)552 static int ctnetlink_dump_info(struct sk_buff *skb, struct nf_conn *ct)
553 {
554 	if (ctnetlink_dump_status(skb, ct) < 0 ||
555 	    ctnetlink_dump_mark(skb, ct, true) < 0 ||
556 	    ctnetlink_dump_secctx(skb, ct) < 0 ||
557 	    ctnetlink_dump_id(skb, ct) < 0 ||
558 	    ctnetlink_dump_use(skb, ct) < 0 ||
559 	    ctnetlink_dump_master(skb, ct) < 0)
560 		return -1;
561 
562 	if (!test_bit(IPS_OFFLOAD_BIT, &ct->status) &&
563 	    (ctnetlink_dump_timeout(skb, ct, false) < 0 ||
564 	     ctnetlink_dump_protoinfo(skb, ct, false) < 0))
565 		return -1;
566 
567 	return 0;
568 }
569 
570 static int
ctnetlink_fill_info(struct sk_buff * skb,u32 portid,u32 seq,u32 type,struct nf_conn * ct,bool extinfo,unsigned int flags)571 ctnetlink_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
572 		    struct nf_conn *ct, bool extinfo, unsigned int flags)
573 {
574 	const struct nf_conntrack_zone *zone;
575 	struct nlmsghdr *nlh;
576 	struct nlattr *nest_parms;
577 	unsigned int event;
578 
579 	if (portid)
580 		flags |= NLM_F_MULTI;
581 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_NEW);
582 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, nf_ct_l3num(ct),
583 			   NFNETLINK_V0, 0);
584 	if (!nlh)
585 		goto nlmsg_failure;
586 
587 	zone = nf_ct_zone(ct);
588 
589 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
590 	if (!nest_parms)
591 		goto nla_put_failure;
592 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
593 		goto nla_put_failure;
594 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
595 				   NF_CT_ZONE_DIR_ORIG) < 0)
596 		goto nla_put_failure;
597 	nla_nest_end(skb, nest_parms);
598 
599 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
600 	if (!nest_parms)
601 		goto nla_put_failure;
602 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
603 		goto nla_put_failure;
604 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
605 				   NF_CT_ZONE_DIR_REPL) < 0)
606 		goto nla_put_failure;
607 	nla_nest_end(skb, nest_parms);
608 
609 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
610 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
611 		goto nla_put_failure;
612 
613 	if (ctnetlink_dump_info(skb, ct) < 0)
614 		goto nla_put_failure;
615 	if (extinfo && ctnetlink_dump_extinfo(skb, ct, type) < 0)
616 		goto nla_put_failure;
617 
618 	nlmsg_end(skb, nlh);
619 	return skb->len;
620 
621 nlmsg_failure:
622 nla_put_failure:
623 	nlmsg_cancel(skb, nlh);
624 	return -1;
625 }
626 
627 static const struct nla_policy cta_ip_nla_policy[CTA_IP_MAX + 1] = {
628 	[CTA_IP_V4_SRC]	= { .type = NLA_U32 },
629 	[CTA_IP_V4_DST]	= { .type = NLA_U32 },
630 	[CTA_IP_V6_SRC]	= { .len = sizeof(__be32) * 4 },
631 	[CTA_IP_V6_DST]	= { .len = sizeof(__be32) * 4 },
632 };
633 
634 #if defined(CONFIG_NETFILTER_NETLINK_GLUE_CT) || defined(CONFIG_NF_CONNTRACK_EVENTS)
ctnetlink_proto_size(const struct nf_conn * ct)635 static size_t ctnetlink_proto_size(const struct nf_conn *ct)
636 {
637 	const struct nf_conntrack_l4proto *l4proto;
638 	size_t len, len4 = 0;
639 
640 	len = nla_policy_len(cta_ip_nla_policy, CTA_IP_MAX + 1);
641 	len *= 3u; /* ORIG, REPLY, MASTER */
642 
643 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
644 	len += l4proto->nlattr_size;
645 	if (l4proto->nlattr_tuple_size) {
646 		len4 = l4proto->nlattr_tuple_size();
647 		len4 *= 3u; /* ORIG, REPLY, MASTER */
648 	}
649 
650 	return len + len4;
651 }
652 
ctnetlink_acct_size(const struct nf_conn * ct)653 static inline size_t ctnetlink_acct_size(const struct nf_conn *ct)
654 {
655 	if (!nf_ct_ext_exist(ct, NF_CT_EXT_ACCT))
656 		return 0;
657 	return 2 * nla_total_size(0) /* CTA_COUNTERS_ORIG|REPL */
658 	       + 2 * nla_total_size_64bit(sizeof(uint64_t)) /* CTA_COUNTERS_PACKETS */
659 	       + 2 * nla_total_size_64bit(sizeof(uint64_t)) /* CTA_COUNTERS_BYTES */
660 	       ;
661 }
662 
ctnetlink_secctx_size(const struct nf_conn * ct)663 static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
664 {
665 #ifdef CONFIG_NF_CONNTRACK_SECMARK
666 	int len, ret;
667 
668 	ret = security_secid_to_secctx(ct->secmark, NULL, &len);
669 	if (ret)
670 		return 0;
671 
672 	return nla_total_size(0) /* CTA_SECCTX */
673 	       + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
674 #else
675 	return 0;
676 #endif
677 }
678 
ctnetlink_timestamp_size(const struct nf_conn * ct)679 static inline size_t ctnetlink_timestamp_size(const struct nf_conn *ct)
680 {
681 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
682 	if (!nf_ct_ext_exist(ct, NF_CT_EXT_TSTAMP))
683 		return 0;
684 	return nla_total_size(0) + 2 * nla_total_size_64bit(sizeof(uint64_t));
685 #else
686 	return 0;
687 #endif
688 }
689 #endif
690 
691 #ifdef CONFIG_NF_CONNTRACK_EVENTS
ctnetlink_nlmsg_size(const struct nf_conn * ct)692 static size_t ctnetlink_nlmsg_size(const struct nf_conn *ct)
693 {
694 	return NLMSG_ALIGN(sizeof(struct nfgenmsg))
695 	       + 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
696 	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
697 	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
698 	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
699 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
700 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
701 	       + ctnetlink_acct_size(ct)
702 	       + ctnetlink_timestamp_size(ct)
703 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
704 	       + nla_total_size(0) /* CTA_PROTOINFO */
705 	       + nla_total_size(0) /* CTA_HELP */
706 	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
707 	       + ctnetlink_secctx_size(ct)
708 #if IS_ENABLED(CONFIG_NF_NAT)
709 	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
710 	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
711 #endif
712 #ifdef CONFIG_NF_CONNTRACK_MARK
713 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
714 #endif
715 #ifdef CONFIG_NF_CONNTRACK_ZONES
716 	       + nla_total_size(sizeof(u_int16_t)) /* CTA_ZONE|CTA_TUPLE_ZONE */
717 #endif
718 	       + ctnetlink_proto_size(ct)
719 	       + ctnetlink_label_size(ct)
720 	       ;
721 }
722 
723 static int
ctnetlink_conntrack_event(unsigned int events,const struct nf_ct_event * item)724 ctnetlink_conntrack_event(unsigned int events, const struct nf_ct_event *item)
725 {
726 	const struct nf_conntrack_zone *zone;
727 	struct net *net;
728 	struct nlmsghdr *nlh;
729 	struct nlattr *nest_parms;
730 	struct nf_conn *ct = item->ct;
731 	struct sk_buff *skb;
732 	unsigned int type;
733 	unsigned int flags = 0, group;
734 	int err;
735 
736 	if (events & (1 << IPCT_DESTROY)) {
737 		type = IPCTNL_MSG_CT_DELETE;
738 		group = NFNLGRP_CONNTRACK_DESTROY;
739 	} else if (events & ((1 << IPCT_NEW) | (1 << IPCT_RELATED))) {
740 		type = IPCTNL_MSG_CT_NEW;
741 		flags = NLM_F_CREATE|NLM_F_EXCL;
742 		group = NFNLGRP_CONNTRACK_NEW;
743 	} else if (events) {
744 		type = IPCTNL_MSG_CT_NEW;
745 		group = NFNLGRP_CONNTRACK_UPDATE;
746 	} else
747 		return 0;
748 
749 	net = nf_ct_net(ct);
750 	if (!item->report && !nfnetlink_has_listeners(net, group))
751 		return 0;
752 
753 	skb = nlmsg_new(ctnetlink_nlmsg_size(ct), GFP_ATOMIC);
754 	if (skb == NULL)
755 		goto errout;
756 
757 	type = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, type);
758 	nlh = nfnl_msg_put(skb, item->portid, 0, type, flags, nf_ct_l3num(ct),
759 			   NFNETLINK_V0, 0);
760 	if (!nlh)
761 		goto nlmsg_failure;
762 
763 	zone = nf_ct_zone(ct);
764 
765 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
766 	if (!nest_parms)
767 		goto nla_put_failure;
768 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
769 		goto nla_put_failure;
770 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
771 				   NF_CT_ZONE_DIR_ORIG) < 0)
772 		goto nla_put_failure;
773 	nla_nest_end(skb, nest_parms);
774 
775 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
776 	if (!nest_parms)
777 		goto nla_put_failure;
778 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
779 		goto nla_put_failure;
780 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
781 				   NF_CT_ZONE_DIR_REPL) < 0)
782 		goto nla_put_failure;
783 	nla_nest_end(skb, nest_parms);
784 
785 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
786 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
787 		goto nla_put_failure;
788 
789 	if (ctnetlink_dump_id(skb, ct) < 0)
790 		goto nla_put_failure;
791 
792 	if (ctnetlink_dump_status(skb, ct) < 0)
793 		goto nla_put_failure;
794 
795 	if (events & (1 << IPCT_DESTROY)) {
796 		if (ctnetlink_dump_timeout(skb, ct, true) < 0)
797 			goto nla_put_failure;
798 
799 		if (ctnetlink_dump_acct(skb, ct, type) < 0 ||
800 		    ctnetlink_dump_timestamp(skb, ct) < 0 ||
801 		    ctnetlink_dump_protoinfo(skb, ct, true) < 0)
802 			goto nla_put_failure;
803 	} else {
804 		if (ctnetlink_dump_timeout(skb, ct, false) < 0)
805 			goto nla_put_failure;
806 
807 		if (events & (1 << IPCT_PROTOINFO) &&
808 		    ctnetlink_dump_protoinfo(skb, ct, false) < 0)
809 			goto nla_put_failure;
810 
811 		if ((events & (1 << IPCT_HELPER) || nfct_help(ct))
812 		    && ctnetlink_dump_helpinfo(skb, ct) < 0)
813 			goto nla_put_failure;
814 
815 #ifdef CONFIG_NF_CONNTRACK_SECMARK
816 		if ((events & (1 << IPCT_SECMARK) || ct->secmark)
817 		    && ctnetlink_dump_secctx(skb, ct) < 0)
818 			goto nla_put_failure;
819 #endif
820 		if (events & (1 << IPCT_LABEL) &&
821 		     ctnetlink_dump_labels(skb, ct) < 0)
822 			goto nla_put_failure;
823 
824 		if (events & (1 << IPCT_RELATED) &&
825 		    ctnetlink_dump_master(skb, ct) < 0)
826 			goto nla_put_failure;
827 
828 		if (events & (1 << IPCT_SEQADJ) &&
829 		    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
830 			goto nla_put_failure;
831 
832 		if (events & (1 << IPCT_SYNPROXY) &&
833 		    ctnetlink_dump_ct_synproxy(skb, ct) < 0)
834 			goto nla_put_failure;
835 	}
836 
837 #ifdef CONFIG_NF_CONNTRACK_MARK
838 	if (ctnetlink_dump_mark(skb, ct, events & (1 << IPCT_MARK)))
839 		goto nla_put_failure;
840 #endif
841 	nlmsg_end(skb, nlh);
842 	err = nfnetlink_send(skb, net, item->portid, group, item->report,
843 			     GFP_ATOMIC);
844 	if (err == -ENOBUFS || err == -EAGAIN)
845 		return -ENOBUFS;
846 
847 	return 0;
848 
849 nla_put_failure:
850 	nlmsg_cancel(skb, nlh);
851 nlmsg_failure:
852 	kfree_skb(skb);
853 errout:
854 	if (nfnetlink_set_err(net, 0, group, -ENOBUFS) > 0)
855 		return -ENOBUFS;
856 
857 	return 0;
858 }
859 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
860 
ctnetlink_done(struct netlink_callback * cb)861 static int ctnetlink_done(struct netlink_callback *cb)
862 {
863 	if (cb->args[1])
864 		nf_ct_put((struct nf_conn *)cb->args[1]);
865 	kfree(cb->data);
866 	return 0;
867 }
868 
869 struct ctnetlink_filter_u32 {
870 	u32 val;
871 	u32 mask;
872 };
873 
874 struct ctnetlink_filter {
875 	u8 family;
876 	bool zone_filter;
877 
878 	u_int32_t orig_flags;
879 	u_int32_t reply_flags;
880 
881 	struct nf_conntrack_tuple orig;
882 	struct nf_conntrack_tuple reply;
883 	struct nf_conntrack_zone zone;
884 
885 	struct ctnetlink_filter_u32 mark;
886 	struct ctnetlink_filter_u32 status;
887 };
888 
889 static const struct nla_policy cta_filter_nla_policy[CTA_FILTER_MAX + 1] = {
890 	[CTA_FILTER_ORIG_FLAGS]		= { .type = NLA_U32 },
891 	[CTA_FILTER_REPLY_FLAGS]	= { .type = NLA_U32 },
892 };
893 
ctnetlink_parse_filter(const struct nlattr * attr,struct ctnetlink_filter * filter)894 static int ctnetlink_parse_filter(const struct nlattr *attr,
895 				  struct ctnetlink_filter *filter)
896 {
897 	struct nlattr *tb[CTA_FILTER_MAX + 1];
898 	int ret = 0;
899 
900 	ret = nla_parse_nested(tb, CTA_FILTER_MAX, attr, cta_filter_nla_policy,
901 			       NULL);
902 	if (ret)
903 		return ret;
904 
905 	if (tb[CTA_FILTER_ORIG_FLAGS]) {
906 		filter->orig_flags = nla_get_u32(tb[CTA_FILTER_ORIG_FLAGS]);
907 		if (filter->orig_flags & ~CTA_FILTER_F_ALL)
908 			return -EOPNOTSUPP;
909 	}
910 
911 	if (tb[CTA_FILTER_REPLY_FLAGS]) {
912 		filter->reply_flags = nla_get_u32(tb[CTA_FILTER_REPLY_FLAGS]);
913 		if (filter->reply_flags & ~CTA_FILTER_F_ALL)
914 			return -EOPNOTSUPP;
915 	}
916 
917 	return 0;
918 }
919 
920 static int ctnetlink_parse_zone(const struct nlattr *attr,
921 				struct nf_conntrack_zone *zone);
922 static int ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
923 					 struct nf_conntrack_tuple *tuple,
924 					 u32 type, u_int8_t l3num,
925 					 struct nf_conntrack_zone *zone,
926 					 u_int32_t flags);
927 
ctnetlink_filter_parse_mark(struct ctnetlink_filter_u32 * mark,const struct nlattr * const cda[])928 static int ctnetlink_filter_parse_mark(struct ctnetlink_filter_u32 *mark,
929 				       const struct nlattr * const cda[])
930 {
931 #ifdef CONFIG_NF_CONNTRACK_MARK
932 	if (cda[CTA_MARK]) {
933 		mark->val = ntohl(nla_get_be32(cda[CTA_MARK]));
934 
935 		if (cda[CTA_MARK_MASK])
936 			mark->mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
937 		else
938 			mark->mask = 0xffffffff;
939 	} else if (cda[CTA_MARK_MASK]) {
940 		return -EINVAL;
941 	}
942 #endif
943 	return 0;
944 }
945 
ctnetlink_filter_parse_status(struct ctnetlink_filter_u32 * status,const struct nlattr * const cda[])946 static int ctnetlink_filter_parse_status(struct ctnetlink_filter_u32 *status,
947 					 const struct nlattr * const cda[])
948 {
949 	if (cda[CTA_STATUS]) {
950 		status->val = ntohl(nla_get_be32(cda[CTA_STATUS]));
951 		if (cda[CTA_STATUS_MASK])
952 			status->mask = ntohl(nla_get_be32(cda[CTA_STATUS_MASK]));
953 		else
954 			status->mask = status->val;
955 
956 		/* status->val == 0? always true, else always false. */
957 		if (status->mask == 0)
958 			return -EINVAL;
959 	} else if (cda[CTA_STATUS_MASK]) {
960 		return -EINVAL;
961 	}
962 
963 	/* CTA_STATUS is NLA_U32, if this fires UAPI needs to be extended */
964 	BUILD_BUG_ON(__IPS_MAX_BIT >= 32);
965 	return 0;
966 }
967 
968 static struct ctnetlink_filter *
ctnetlink_alloc_filter(const struct nlattr * const cda[],u8 family)969 ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
970 {
971 	struct ctnetlink_filter *filter;
972 	int err;
973 
974 #ifndef CONFIG_NF_CONNTRACK_MARK
975 	if (cda[CTA_MARK] || cda[CTA_MARK_MASK])
976 		return ERR_PTR(-EOPNOTSUPP);
977 #endif
978 
979 	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
980 	if (filter == NULL)
981 		return ERR_PTR(-ENOMEM);
982 
983 	filter->family = family;
984 
985 	err = ctnetlink_filter_parse_mark(&filter->mark, cda);
986 	if (err)
987 		goto err_filter;
988 
989 	err = ctnetlink_filter_parse_status(&filter->status, cda);
990 	if (err)
991 		goto err_filter;
992 
993 	if (cda[CTA_ZONE]) {
994 		err = ctnetlink_parse_zone(cda[CTA_ZONE], &filter->zone);
995 		if (err < 0)
996 			goto err_filter;
997 		filter->zone_filter = true;
998 	}
999 
1000 	if (!cda[CTA_FILTER])
1001 		return filter;
1002 
1003 	err = ctnetlink_parse_filter(cda[CTA_FILTER], filter);
1004 	if (err < 0)
1005 		goto err_filter;
1006 
1007 	if (filter->orig_flags) {
1008 		if (!cda[CTA_TUPLE_ORIG]) {
1009 			err = -EINVAL;
1010 			goto err_filter;
1011 		}
1012 
1013 		err = ctnetlink_parse_tuple_filter(cda, &filter->orig,
1014 						   CTA_TUPLE_ORIG,
1015 						   filter->family,
1016 						   &filter->zone,
1017 						   filter->orig_flags);
1018 		if (err < 0)
1019 			goto err_filter;
1020 	}
1021 
1022 	if (filter->reply_flags) {
1023 		if (!cda[CTA_TUPLE_REPLY]) {
1024 			err = -EINVAL;
1025 			goto err_filter;
1026 		}
1027 
1028 		err = ctnetlink_parse_tuple_filter(cda, &filter->reply,
1029 						   CTA_TUPLE_REPLY,
1030 						   filter->family,
1031 						   &filter->zone,
1032 						   filter->reply_flags);
1033 		if (err < 0)
1034 			goto err_filter;
1035 	}
1036 
1037 	return filter;
1038 
1039 err_filter:
1040 	kfree(filter);
1041 
1042 	return ERR_PTR(err);
1043 }
1044 
ctnetlink_needs_filter(u8 family,const struct nlattr * const * cda)1045 static bool ctnetlink_needs_filter(u8 family, const struct nlattr * const *cda)
1046 {
1047 	return family || cda[CTA_MARK] || cda[CTA_FILTER] || cda[CTA_STATUS] || cda[CTA_ZONE];
1048 }
1049 
ctnetlink_start(struct netlink_callback * cb)1050 static int ctnetlink_start(struct netlink_callback *cb)
1051 {
1052 	const struct nlattr * const *cda = cb->data;
1053 	struct ctnetlink_filter *filter = NULL;
1054 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1055 	u8 family = nfmsg->nfgen_family;
1056 
1057 	if (ctnetlink_needs_filter(family, cda)) {
1058 		filter = ctnetlink_alloc_filter(cda, family);
1059 		if (IS_ERR(filter))
1060 			return PTR_ERR(filter);
1061 	}
1062 
1063 	cb->data = filter;
1064 	return 0;
1065 }
1066 
ctnetlink_filter_match_tuple(struct nf_conntrack_tuple * filter_tuple,struct nf_conntrack_tuple * ct_tuple,u_int32_t flags,int family)1067 static int ctnetlink_filter_match_tuple(struct nf_conntrack_tuple *filter_tuple,
1068 					struct nf_conntrack_tuple *ct_tuple,
1069 					u_int32_t flags, int family)
1070 {
1071 	switch (family) {
1072 	case NFPROTO_IPV4:
1073 		if ((flags & CTA_FILTER_FLAG(CTA_IP_SRC)) &&
1074 		    filter_tuple->src.u3.ip != ct_tuple->src.u3.ip)
1075 			return  0;
1076 
1077 		if ((flags & CTA_FILTER_FLAG(CTA_IP_DST)) &&
1078 		    filter_tuple->dst.u3.ip != ct_tuple->dst.u3.ip)
1079 			return  0;
1080 		break;
1081 	case NFPROTO_IPV6:
1082 		if ((flags & CTA_FILTER_FLAG(CTA_IP_SRC)) &&
1083 		    !ipv6_addr_cmp(&filter_tuple->src.u3.in6,
1084 				   &ct_tuple->src.u3.in6))
1085 			return 0;
1086 
1087 		if ((flags & CTA_FILTER_FLAG(CTA_IP_DST)) &&
1088 		    !ipv6_addr_cmp(&filter_tuple->dst.u3.in6,
1089 				   &ct_tuple->dst.u3.in6))
1090 			return 0;
1091 		break;
1092 	}
1093 
1094 	if ((flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)) &&
1095 	    filter_tuple->dst.protonum != ct_tuple->dst.protonum)
1096 		return 0;
1097 
1098 	switch (ct_tuple->dst.protonum) {
1099 	case IPPROTO_TCP:
1100 	case IPPROTO_UDP:
1101 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_SRC_PORT)) &&
1102 		    filter_tuple->src.u.tcp.port != ct_tuple->src.u.tcp.port)
1103 			return 0;
1104 
1105 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_DST_PORT)) &&
1106 		    filter_tuple->dst.u.tcp.port != ct_tuple->dst.u.tcp.port)
1107 			return 0;
1108 		break;
1109 	case IPPROTO_ICMP:
1110 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_TYPE)) &&
1111 		    filter_tuple->dst.u.icmp.type != ct_tuple->dst.u.icmp.type)
1112 			return 0;
1113 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_CODE)) &&
1114 		    filter_tuple->dst.u.icmp.code != ct_tuple->dst.u.icmp.code)
1115 			return 0;
1116 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_ID)) &&
1117 		    filter_tuple->src.u.icmp.id != ct_tuple->src.u.icmp.id)
1118 			return 0;
1119 		break;
1120 	case IPPROTO_ICMPV6:
1121 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_TYPE)) &&
1122 		    filter_tuple->dst.u.icmp.type != ct_tuple->dst.u.icmp.type)
1123 			return 0;
1124 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_CODE)) &&
1125 		    filter_tuple->dst.u.icmp.code != ct_tuple->dst.u.icmp.code)
1126 			return 0;
1127 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_ID)) &&
1128 		    filter_tuple->src.u.icmp.id != ct_tuple->src.u.icmp.id)
1129 			return 0;
1130 		break;
1131 	}
1132 
1133 	return 1;
1134 }
1135 
ctnetlink_filter_match(struct nf_conn * ct,void * data)1136 static int ctnetlink_filter_match(struct nf_conn *ct, void *data)
1137 {
1138 	struct ctnetlink_filter *filter = data;
1139 	struct nf_conntrack_tuple *tuple;
1140 	u32 status;
1141 
1142 	if (filter == NULL)
1143 		goto out;
1144 
1145 	/* Match entries of a given L3 protocol number.
1146 	 * If it is not specified, ie. l3proto == 0,
1147 	 * then match everything.
1148 	 */
1149 	if (filter->family && nf_ct_l3num(ct) != filter->family)
1150 		goto ignore_entry;
1151 
1152 	if (filter->zone_filter &&
1153 	    !nf_ct_zone_equal_any(ct, &filter->zone))
1154 		goto ignore_entry;
1155 
1156 	if (filter->orig_flags) {
1157 		tuple = nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL);
1158 		if (!ctnetlink_filter_match_tuple(&filter->orig, tuple,
1159 						  filter->orig_flags,
1160 						  filter->family))
1161 			goto ignore_entry;
1162 	}
1163 
1164 	if (filter->reply_flags) {
1165 		tuple = nf_ct_tuple(ct, IP_CT_DIR_REPLY);
1166 		if (!ctnetlink_filter_match_tuple(&filter->reply, tuple,
1167 						  filter->reply_flags,
1168 						  filter->family))
1169 			goto ignore_entry;
1170 	}
1171 
1172 #ifdef CONFIG_NF_CONNTRACK_MARK
1173 	if ((READ_ONCE(ct->mark) & filter->mark.mask) != filter->mark.val)
1174 		goto ignore_entry;
1175 #endif
1176 	status = (u32)READ_ONCE(ct->status);
1177 	if ((status & filter->status.mask) != filter->status.val)
1178 		goto ignore_entry;
1179 
1180 out:
1181 	return 1;
1182 
1183 ignore_entry:
1184 	return 0;
1185 }
1186 
1187 static int
ctnetlink_dump_table(struct sk_buff * skb,struct netlink_callback * cb)1188 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1189 {
1190 	unsigned int flags = cb->data ? NLM_F_DUMP_FILTERED : 0;
1191 	struct net *net = sock_net(skb->sk);
1192 	struct nf_conn *ct, *last;
1193 	struct nf_conntrack_tuple_hash *h;
1194 	struct hlist_nulls_node *n;
1195 	struct nf_conn *nf_ct_evict[8];
1196 	int res, i;
1197 	spinlock_t *lockp;
1198 
1199 	last = (struct nf_conn *)cb->args[1];
1200 	i = 0;
1201 
1202 	local_bh_disable();
1203 	for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
1204 restart:
1205 		while (i) {
1206 			i--;
1207 			if (nf_ct_should_gc(nf_ct_evict[i]))
1208 				nf_ct_kill(nf_ct_evict[i]);
1209 			nf_ct_put(nf_ct_evict[i]);
1210 		}
1211 
1212 		lockp = &nf_conntrack_locks[cb->args[0] % CONNTRACK_LOCKS];
1213 		nf_conntrack_lock(lockp);
1214 		if (cb->args[0] >= nf_conntrack_htable_size) {
1215 			spin_unlock(lockp);
1216 			goto out;
1217 		}
1218 		hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[cb->args[0]],
1219 					   hnnode) {
1220 			ct = nf_ct_tuplehash_to_ctrack(h);
1221 			if (nf_ct_is_expired(ct)) {
1222 				/* need to defer nf_ct_kill() until lock is released */
1223 				if (i < ARRAY_SIZE(nf_ct_evict) &&
1224 				    refcount_inc_not_zero(&ct->ct_general.use))
1225 					nf_ct_evict[i++] = ct;
1226 				continue;
1227 			}
1228 
1229 			if (!net_eq(net, nf_ct_net(ct)))
1230 				continue;
1231 
1232 			if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
1233 				continue;
1234 
1235 			if (cb->args[1]) {
1236 				if (ct != last)
1237 					continue;
1238 				cb->args[1] = 0;
1239 			}
1240 			if (!ctnetlink_filter_match(ct, cb->data))
1241 				continue;
1242 
1243 			res =
1244 			ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
1245 					    cb->nlh->nlmsg_seq,
1246 					    NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
1247 					    ct, true, flags);
1248 			if (res < 0) {
1249 				nf_conntrack_get(&ct->ct_general);
1250 				cb->args[1] = (unsigned long)ct;
1251 				spin_unlock(lockp);
1252 				goto out;
1253 			}
1254 		}
1255 		spin_unlock(lockp);
1256 		if (cb->args[1]) {
1257 			cb->args[1] = 0;
1258 			goto restart;
1259 		}
1260 	}
1261 out:
1262 	local_bh_enable();
1263 	if (last) {
1264 		/* nf ct hash resize happened, now clear the leftover. */
1265 		if ((struct nf_conn *)cb->args[1] == last)
1266 			cb->args[1] = 0;
1267 
1268 		nf_ct_put(last);
1269 	}
1270 
1271 	while (i) {
1272 		i--;
1273 		if (nf_ct_should_gc(nf_ct_evict[i]))
1274 			nf_ct_kill(nf_ct_evict[i]);
1275 		nf_ct_put(nf_ct_evict[i]);
1276 	}
1277 
1278 	return skb->len;
1279 }
1280 
ipv4_nlattr_to_tuple(struct nlattr * tb[],struct nf_conntrack_tuple * t,u_int32_t flags)1281 static int ipv4_nlattr_to_tuple(struct nlattr *tb[],
1282 				struct nf_conntrack_tuple *t,
1283 				u_int32_t flags)
1284 {
1285 	if (flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1286 		if (!tb[CTA_IP_V4_SRC])
1287 			return -EINVAL;
1288 
1289 		t->src.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_SRC]);
1290 	}
1291 
1292 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST)) {
1293 		if (!tb[CTA_IP_V4_DST])
1294 			return -EINVAL;
1295 
1296 		t->dst.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_DST]);
1297 	}
1298 
1299 	return 0;
1300 }
1301 
ipv6_nlattr_to_tuple(struct nlattr * tb[],struct nf_conntrack_tuple * t,u_int32_t flags)1302 static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
1303 				struct nf_conntrack_tuple *t,
1304 				u_int32_t flags)
1305 {
1306 	if (flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1307 		if (!tb[CTA_IP_V6_SRC])
1308 			return -EINVAL;
1309 
1310 		t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]);
1311 	}
1312 
1313 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST)) {
1314 		if (!tb[CTA_IP_V6_DST])
1315 			return -EINVAL;
1316 
1317 		t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]);
1318 	}
1319 
1320 	return 0;
1321 }
1322 
ctnetlink_parse_tuple_ip(struct nlattr * attr,struct nf_conntrack_tuple * tuple,u_int32_t flags)1323 static int ctnetlink_parse_tuple_ip(struct nlattr *attr,
1324 				    struct nf_conntrack_tuple *tuple,
1325 				    u_int32_t flags)
1326 {
1327 	struct nlattr *tb[CTA_IP_MAX+1];
1328 	int ret = 0;
1329 
1330 	ret = nla_parse_nested_deprecated(tb, CTA_IP_MAX, attr,
1331 					  cta_ip_nla_policy, NULL);
1332 	if (ret < 0)
1333 		return ret;
1334 
1335 	switch (tuple->src.l3num) {
1336 	case NFPROTO_IPV4:
1337 		ret = ipv4_nlattr_to_tuple(tb, tuple, flags);
1338 		break;
1339 	case NFPROTO_IPV6:
1340 		ret = ipv6_nlattr_to_tuple(tb, tuple, flags);
1341 		break;
1342 	}
1343 
1344 	return ret;
1345 }
1346 
1347 static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
1348 	[CTA_PROTO_NUM]	= { .type = NLA_U8 },
1349 };
1350 
ctnetlink_parse_tuple_proto(struct nlattr * attr,struct nf_conntrack_tuple * tuple,u_int32_t flags)1351 static int ctnetlink_parse_tuple_proto(struct nlattr *attr,
1352 				       struct nf_conntrack_tuple *tuple,
1353 				       u_int32_t flags)
1354 {
1355 	const struct nf_conntrack_l4proto *l4proto;
1356 	struct nlattr *tb[CTA_PROTO_MAX+1];
1357 	int ret = 0;
1358 
1359 	ret = nla_parse_nested_deprecated(tb, CTA_PROTO_MAX, attr,
1360 					  proto_nla_policy, NULL);
1361 	if (ret < 0)
1362 		return ret;
1363 
1364 	if (!(flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)))
1365 		return 0;
1366 
1367 	if (!tb[CTA_PROTO_NUM])
1368 		return -EINVAL;
1369 
1370 	tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
1371 
1372 	rcu_read_lock();
1373 	l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
1374 
1375 	if (likely(l4proto->nlattr_to_tuple)) {
1376 		ret = nla_validate_nested_deprecated(attr, CTA_PROTO_MAX,
1377 						     l4proto->nla_policy,
1378 						     NULL);
1379 		if (ret == 0)
1380 			ret = l4proto->nlattr_to_tuple(tb, tuple, flags);
1381 	}
1382 
1383 	rcu_read_unlock();
1384 
1385 	return ret;
1386 }
1387 
1388 static int
ctnetlink_parse_zone(const struct nlattr * attr,struct nf_conntrack_zone * zone)1389 ctnetlink_parse_zone(const struct nlattr *attr,
1390 		     struct nf_conntrack_zone *zone)
1391 {
1392 	nf_ct_zone_init(zone, NF_CT_DEFAULT_ZONE_ID,
1393 			NF_CT_DEFAULT_ZONE_DIR, 0);
1394 #ifdef CONFIG_NF_CONNTRACK_ZONES
1395 	if (attr)
1396 		zone->id = ntohs(nla_get_be16(attr));
1397 #else
1398 	if (attr)
1399 		return -EOPNOTSUPP;
1400 #endif
1401 	return 0;
1402 }
1403 
1404 static int
ctnetlink_parse_tuple_zone(struct nlattr * attr,enum ctattr_type type,struct nf_conntrack_zone * zone)1405 ctnetlink_parse_tuple_zone(struct nlattr *attr, enum ctattr_type type,
1406 			   struct nf_conntrack_zone *zone)
1407 {
1408 	int ret;
1409 
1410 	if (zone->id != NF_CT_DEFAULT_ZONE_ID)
1411 		return -EINVAL;
1412 
1413 	ret = ctnetlink_parse_zone(attr, zone);
1414 	if (ret < 0)
1415 		return ret;
1416 
1417 	if (type == CTA_TUPLE_REPLY)
1418 		zone->dir = NF_CT_ZONE_DIR_REPL;
1419 	else
1420 		zone->dir = NF_CT_ZONE_DIR_ORIG;
1421 
1422 	return 0;
1423 }
1424 
1425 static const struct nla_policy tuple_nla_policy[CTA_TUPLE_MAX+1] = {
1426 	[CTA_TUPLE_IP]		= { .type = NLA_NESTED },
1427 	[CTA_TUPLE_PROTO]	= { .type = NLA_NESTED },
1428 	[CTA_TUPLE_ZONE]	= { .type = NLA_U16 },
1429 };
1430 
1431 #define CTA_FILTER_F_ALL_CTA_PROTO \
1432   (CTA_FILTER_F_CTA_PROTO_SRC_PORT | \
1433    CTA_FILTER_F_CTA_PROTO_DST_PORT | \
1434    CTA_FILTER_F_CTA_PROTO_ICMP_TYPE | \
1435    CTA_FILTER_F_CTA_PROTO_ICMP_CODE | \
1436    CTA_FILTER_F_CTA_PROTO_ICMP_ID | \
1437    CTA_FILTER_F_CTA_PROTO_ICMPV6_TYPE | \
1438    CTA_FILTER_F_CTA_PROTO_ICMPV6_CODE | \
1439    CTA_FILTER_F_CTA_PROTO_ICMPV6_ID)
1440 
1441 static int
ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],struct nf_conntrack_tuple * tuple,u32 type,u_int8_t l3num,struct nf_conntrack_zone * zone,u_int32_t flags)1442 ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
1443 			      struct nf_conntrack_tuple *tuple, u32 type,
1444 			      u_int8_t l3num, struct nf_conntrack_zone *zone,
1445 			      u_int32_t flags)
1446 {
1447 	struct nlattr *tb[CTA_TUPLE_MAX+1];
1448 	int err;
1449 
1450 	memset(tuple, 0, sizeof(*tuple));
1451 
1452 	err = nla_parse_nested_deprecated(tb, CTA_TUPLE_MAX, cda[type],
1453 					  tuple_nla_policy, NULL);
1454 	if (err < 0)
1455 		return err;
1456 
1457 	if (l3num != NFPROTO_IPV4 && l3num != NFPROTO_IPV6)
1458 		return -EOPNOTSUPP;
1459 	tuple->src.l3num = l3num;
1460 
1461 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST) ||
1462 	    flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1463 		if (!tb[CTA_TUPLE_IP])
1464 			return -EINVAL;
1465 
1466 		err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple, flags);
1467 		if (err < 0)
1468 			return err;
1469 	}
1470 
1471 	if (flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)) {
1472 		if (!tb[CTA_TUPLE_PROTO])
1473 			return -EINVAL;
1474 
1475 		err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple, flags);
1476 		if (err < 0)
1477 			return err;
1478 	} else if (flags & CTA_FILTER_FLAG(ALL_CTA_PROTO)) {
1479 		/* Can't manage proto flags without a protonum  */
1480 		return -EINVAL;
1481 	}
1482 
1483 	if ((flags & CTA_FILTER_FLAG(CTA_TUPLE_ZONE)) && tb[CTA_TUPLE_ZONE]) {
1484 		if (!zone)
1485 			return -EINVAL;
1486 
1487 		err = ctnetlink_parse_tuple_zone(tb[CTA_TUPLE_ZONE],
1488 						 type, zone);
1489 		if (err < 0)
1490 			return err;
1491 	}
1492 
1493 	/* orig and expect tuples get DIR_ORIGINAL */
1494 	if (type == CTA_TUPLE_REPLY)
1495 		tuple->dst.dir = IP_CT_DIR_REPLY;
1496 	else
1497 		tuple->dst.dir = IP_CT_DIR_ORIGINAL;
1498 
1499 	return 0;
1500 }
1501 
1502 static int
ctnetlink_parse_tuple(const struct nlattr * const cda[],struct nf_conntrack_tuple * tuple,u32 type,u_int8_t l3num,struct nf_conntrack_zone * zone)1503 ctnetlink_parse_tuple(const struct nlattr * const cda[],
1504 		      struct nf_conntrack_tuple *tuple, u32 type,
1505 		      u_int8_t l3num, struct nf_conntrack_zone *zone)
1506 {
1507 	return ctnetlink_parse_tuple_filter(cda, tuple, type, l3num, zone,
1508 					    CTA_FILTER_FLAG(ALL));
1509 }
1510 
1511 static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = {
1512 	[CTA_HELP_NAME]		= { .type = NLA_NUL_STRING,
1513 				    .len = NF_CT_HELPER_NAME_LEN - 1 },
1514 };
1515 
ctnetlink_parse_help(const struct nlattr * attr,char ** helper_name,struct nlattr ** helpinfo)1516 static int ctnetlink_parse_help(const struct nlattr *attr, char **helper_name,
1517 				struct nlattr **helpinfo)
1518 {
1519 	int err;
1520 	struct nlattr *tb[CTA_HELP_MAX+1];
1521 
1522 	err = nla_parse_nested_deprecated(tb, CTA_HELP_MAX, attr,
1523 					  help_nla_policy, NULL);
1524 	if (err < 0)
1525 		return err;
1526 
1527 	if (!tb[CTA_HELP_NAME])
1528 		return -EINVAL;
1529 
1530 	*helper_name = nla_data(tb[CTA_HELP_NAME]);
1531 
1532 	if (tb[CTA_HELP_INFO])
1533 		*helpinfo = tb[CTA_HELP_INFO];
1534 
1535 	return 0;
1536 }
1537 
1538 static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
1539 	[CTA_TUPLE_ORIG]	= { .type = NLA_NESTED },
1540 	[CTA_TUPLE_REPLY]	= { .type = NLA_NESTED },
1541 	[CTA_STATUS] 		= { .type = NLA_U32 },
1542 	[CTA_PROTOINFO]		= { .type = NLA_NESTED },
1543 	[CTA_HELP]		= { .type = NLA_NESTED },
1544 	[CTA_NAT_SRC]		= { .type = NLA_NESTED },
1545 	[CTA_TIMEOUT] 		= { .type = NLA_U32 },
1546 	[CTA_MARK]		= { .type = NLA_U32 },
1547 	[CTA_ID]		= { .type = NLA_U32 },
1548 	[CTA_NAT_DST]		= { .type = NLA_NESTED },
1549 	[CTA_TUPLE_MASTER]	= { .type = NLA_NESTED },
1550 	[CTA_NAT_SEQ_ADJ_ORIG]  = { .type = NLA_NESTED },
1551 	[CTA_NAT_SEQ_ADJ_REPLY] = { .type = NLA_NESTED },
1552 	[CTA_ZONE]		= { .type = NLA_U16 },
1553 	[CTA_MARK_MASK]		= { .type = NLA_U32 },
1554 	[CTA_LABELS]		= { .type = NLA_BINARY,
1555 				    .len = NF_CT_LABELS_MAX_SIZE },
1556 	[CTA_LABELS_MASK]	= { .type = NLA_BINARY,
1557 				    .len = NF_CT_LABELS_MAX_SIZE },
1558 	[CTA_FILTER]		= { .type = NLA_NESTED },
1559 	[CTA_STATUS_MASK]	= { .type = NLA_U32 },
1560 };
1561 
ctnetlink_flush_iterate(struct nf_conn * ct,void * data)1562 static int ctnetlink_flush_iterate(struct nf_conn *ct, void *data)
1563 {
1564 	return ctnetlink_filter_match(ct, data);
1565 }
1566 
ctnetlink_flush_conntrack(struct net * net,const struct nlattr * const cda[],u32 portid,int report,u8 family)1567 static int ctnetlink_flush_conntrack(struct net *net,
1568 				     const struct nlattr * const cda[],
1569 				     u32 portid, int report, u8 family)
1570 {
1571 	struct ctnetlink_filter *filter = NULL;
1572 	struct nf_ct_iter_data iter = {
1573 		.net		= net,
1574 		.portid		= portid,
1575 		.report		= report,
1576 	};
1577 
1578 	if (ctnetlink_needs_filter(family, cda)) {
1579 		filter = ctnetlink_alloc_filter(cda, family);
1580 		if (IS_ERR(filter))
1581 			return PTR_ERR(filter);
1582 
1583 		iter.data = filter;
1584 	}
1585 
1586 	nf_ct_iterate_cleanup_net(ctnetlink_flush_iterate, &iter);
1587 	kfree(filter);
1588 
1589 	return 0;
1590 }
1591 
ctnetlink_del_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1592 static int ctnetlink_del_conntrack(struct sk_buff *skb,
1593 				   const struct nfnl_info *info,
1594 				   const struct nlattr * const cda[])
1595 {
1596 	u8 family = info->nfmsg->nfgen_family;
1597 	struct nf_conntrack_tuple_hash *h;
1598 	struct nf_conntrack_tuple tuple;
1599 	struct nf_conntrack_zone zone;
1600 	struct nf_conn *ct;
1601 	int err;
1602 
1603 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1604 	if (err < 0)
1605 		return err;
1606 
1607 	if (cda[CTA_TUPLE_ORIG] && !cda[CTA_FILTER])
1608 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG,
1609 					    family, &zone);
1610 	else if (cda[CTA_TUPLE_REPLY] && !cda[CTA_FILTER])
1611 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY,
1612 					    family, &zone);
1613 	else {
1614 		u8 u3 = info->nfmsg->version || cda[CTA_FILTER] ? family : AF_UNSPEC;
1615 
1616 		return ctnetlink_flush_conntrack(info->net, cda,
1617 						 NETLINK_CB(skb).portid,
1618 						 nlmsg_report(info->nlh), u3);
1619 	}
1620 
1621 	if (err < 0)
1622 		return err;
1623 
1624 	h = nf_conntrack_find_get(info->net, &zone, &tuple);
1625 	if (!h)
1626 		return -ENOENT;
1627 
1628 	ct = nf_ct_tuplehash_to_ctrack(h);
1629 
1630 	if (cda[CTA_ID]) {
1631 		__be32 id = nla_get_be32(cda[CTA_ID]);
1632 
1633 		if (id != (__force __be32)nf_ct_get_id(ct)) {
1634 			nf_ct_put(ct);
1635 			return -ENOENT;
1636 		}
1637 	}
1638 
1639 	nf_ct_delete(ct, NETLINK_CB(skb).portid, nlmsg_report(info->nlh));
1640 	nf_ct_put(ct);
1641 
1642 	return 0;
1643 }
1644 
ctnetlink_get_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1645 static int ctnetlink_get_conntrack(struct sk_buff *skb,
1646 				   const struct nfnl_info *info,
1647 				   const struct nlattr * const cda[])
1648 {
1649 	u_int8_t u3 = info->nfmsg->nfgen_family;
1650 	struct nf_conntrack_tuple_hash *h;
1651 	struct nf_conntrack_tuple tuple;
1652 	struct nf_conntrack_zone zone;
1653 	struct sk_buff *skb2;
1654 	struct nf_conn *ct;
1655 	int err;
1656 
1657 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1658 		struct netlink_dump_control c = {
1659 			.start = ctnetlink_start,
1660 			.dump = ctnetlink_dump_table,
1661 			.done = ctnetlink_done,
1662 			.data = (void *)cda,
1663 		};
1664 
1665 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1666 	}
1667 
1668 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1669 	if (err < 0)
1670 		return err;
1671 
1672 	if (cda[CTA_TUPLE_ORIG])
1673 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG,
1674 					    u3, &zone);
1675 	else if (cda[CTA_TUPLE_REPLY])
1676 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY,
1677 					    u3, &zone);
1678 	else
1679 		return -EINVAL;
1680 
1681 	if (err < 0)
1682 		return err;
1683 
1684 	h = nf_conntrack_find_get(info->net, &zone, &tuple);
1685 	if (!h)
1686 		return -ENOENT;
1687 
1688 	ct = nf_ct_tuplehash_to_ctrack(h);
1689 
1690 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1691 	if (!skb2) {
1692 		nf_ct_put(ct);
1693 		return -ENOMEM;
1694 	}
1695 
1696 	err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).portid,
1697 				  info->nlh->nlmsg_seq,
1698 				  NFNL_MSG_TYPE(info->nlh->nlmsg_type), ct,
1699 				  true, 0);
1700 	nf_ct_put(ct);
1701 	if (err <= 0) {
1702 		kfree_skb(skb2);
1703 		return -ENOMEM;
1704 	}
1705 
1706 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
1707 }
1708 
ctnetlink_done_list(struct netlink_callback * cb)1709 static int ctnetlink_done_list(struct netlink_callback *cb)
1710 {
1711 	struct ctnetlink_list_dump_ctx *ctx = (void *)cb->ctx;
1712 
1713 	if (ctx->last)
1714 		nf_ct_put(ctx->last);
1715 
1716 	return 0;
1717 }
1718 
1719 #ifdef CONFIG_NF_CONNTRACK_EVENTS
ctnetlink_dump_one_entry(struct sk_buff * skb,struct netlink_callback * cb,struct nf_conn * ct,bool dying)1720 static int ctnetlink_dump_one_entry(struct sk_buff *skb,
1721 				    struct netlink_callback *cb,
1722 				    struct nf_conn *ct,
1723 				    bool dying)
1724 {
1725 	struct ctnetlink_list_dump_ctx *ctx = (void *)cb->ctx;
1726 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1727 	u8 l3proto = nfmsg->nfgen_family;
1728 	int res;
1729 
1730 	if (l3proto && nf_ct_l3num(ct) != l3proto)
1731 		return 0;
1732 
1733 	if (ctx->last) {
1734 		if (ct != ctx->last)
1735 			return 0;
1736 
1737 		ctx->last = NULL;
1738 	}
1739 
1740 	/* We can't dump extension info for the unconfirmed
1741 	 * list because unconfirmed conntracks can have
1742 	 * ct->ext reallocated (and thus freed).
1743 	 *
1744 	 * In the dying list case ct->ext can't be free'd
1745 	 * until after we drop pcpu->lock.
1746 	 */
1747 	res = ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
1748 				  cb->nlh->nlmsg_seq,
1749 				  NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
1750 				  ct, dying, 0);
1751 	if (res < 0) {
1752 		if (!refcount_inc_not_zero(&ct->ct_general.use))
1753 			return 0;
1754 
1755 		ctx->last = ct;
1756 	}
1757 
1758 	return res;
1759 }
1760 #endif
1761 
1762 static int
ctnetlink_dump_unconfirmed(struct sk_buff * skb,struct netlink_callback * cb)1763 ctnetlink_dump_unconfirmed(struct sk_buff *skb, struct netlink_callback *cb)
1764 {
1765 	return 0;
1766 }
1767 
1768 static int
ctnetlink_dump_dying(struct sk_buff * skb,struct netlink_callback * cb)1769 ctnetlink_dump_dying(struct sk_buff *skb, struct netlink_callback *cb)
1770 {
1771 	struct ctnetlink_list_dump_ctx *ctx = (void *)cb->ctx;
1772 	struct nf_conn *last = ctx->last;
1773 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1774 	const struct net *net = sock_net(skb->sk);
1775 	struct nf_conntrack_net_ecache *ecache_net;
1776 	struct nf_conntrack_tuple_hash *h;
1777 	struct hlist_nulls_node *n;
1778 #endif
1779 
1780 	if (ctx->done)
1781 		return 0;
1782 
1783 	ctx->last = NULL;
1784 
1785 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1786 	ecache_net = nf_conn_pernet_ecache(net);
1787 	spin_lock_bh(&ecache_net->dying_lock);
1788 
1789 	hlist_nulls_for_each_entry(h, n, &ecache_net->dying_list, hnnode) {
1790 		struct nf_conn *ct;
1791 		int res;
1792 
1793 		ct = nf_ct_tuplehash_to_ctrack(h);
1794 		if (last && last != ct)
1795 			continue;
1796 
1797 		res = ctnetlink_dump_one_entry(skb, cb, ct, true);
1798 		if (res < 0) {
1799 			spin_unlock_bh(&ecache_net->dying_lock);
1800 			nf_ct_put(last);
1801 			return skb->len;
1802 		}
1803 
1804 		nf_ct_put(last);
1805 		last = NULL;
1806 	}
1807 
1808 	spin_unlock_bh(&ecache_net->dying_lock);
1809 #endif
1810 	ctx->done = true;
1811 	nf_ct_put(last);
1812 
1813 	return skb->len;
1814 }
1815 
ctnetlink_get_ct_dying(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1816 static int ctnetlink_get_ct_dying(struct sk_buff *skb,
1817 				  const struct nfnl_info *info,
1818 				  const struct nlattr * const cda[])
1819 {
1820 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1821 		struct netlink_dump_control c = {
1822 			.dump = ctnetlink_dump_dying,
1823 			.done = ctnetlink_done_list,
1824 		};
1825 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1826 	}
1827 
1828 	return -EOPNOTSUPP;
1829 }
1830 
ctnetlink_get_ct_unconfirmed(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1831 static int ctnetlink_get_ct_unconfirmed(struct sk_buff *skb,
1832 					const struct nfnl_info *info,
1833 					const struct nlattr * const cda[])
1834 {
1835 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1836 		struct netlink_dump_control c = {
1837 			.dump = ctnetlink_dump_unconfirmed,
1838 			.done = ctnetlink_done_list,
1839 		};
1840 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1841 	}
1842 
1843 	return -EOPNOTSUPP;
1844 }
1845 
1846 #if IS_ENABLED(CONFIG_NF_NAT)
1847 static int
ctnetlink_parse_nat_setup(struct nf_conn * ct,enum nf_nat_manip_type manip,const struct nlattr * attr)1848 ctnetlink_parse_nat_setup(struct nf_conn *ct,
1849 			  enum nf_nat_manip_type manip,
1850 			  const struct nlattr *attr)
1851 	__must_hold(RCU)
1852 {
1853 	const struct nf_nat_hook *nat_hook;
1854 	int err;
1855 
1856 	nat_hook = rcu_dereference(nf_nat_hook);
1857 	if (!nat_hook) {
1858 #ifdef CONFIG_MODULES
1859 		rcu_read_unlock();
1860 		nfnl_unlock(NFNL_SUBSYS_CTNETLINK);
1861 		if (request_module("nf-nat") < 0) {
1862 			nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1863 			rcu_read_lock();
1864 			return -EOPNOTSUPP;
1865 		}
1866 		nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1867 		rcu_read_lock();
1868 		nat_hook = rcu_dereference(nf_nat_hook);
1869 		if (nat_hook)
1870 			return -EAGAIN;
1871 #endif
1872 		return -EOPNOTSUPP;
1873 	}
1874 
1875 	err = nat_hook->parse_nat_setup(ct, manip, attr);
1876 	if (err == -EAGAIN) {
1877 #ifdef CONFIG_MODULES
1878 		rcu_read_unlock();
1879 		nfnl_unlock(NFNL_SUBSYS_CTNETLINK);
1880 		if (request_module("nf-nat-%u", nf_ct_l3num(ct)) < 0) {
1881 			nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1882 			rcu_read_lock();
1883 			return -EOPNOTSUPP;
1884 		}
1885 		nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1886 		rcu_read_lock();
1887 #else
1888 		err = -EOPNOTSUPP;
1889 #endif
1890 	}
1891 	return err;
1892 }
1893 #endif
1894 
1895 static int
ctnetlink_change_status(struct nf_conn * ct,const struct nlattr * const cda[])1896 ctnetlink_change_status(struct nf_conn *ct, const struct nlattr * const cda[])
1897 {
1898 	return nf_ct_change_status_common(ct, ntohl(nla_get_be32(cda[CTA_STATUS])));
1899 }
1900 
1901 static int
ctnetlink_setup_nat(struct nf_conn * ct,const struct nlattr * const cda[])1902 ctnetlink_setup_nat(struct nf_conn *ct, const struct nlattr * const cda[])
1903 {
1904 #if IS_ENABLED(CONFIG_NF_NAT)
1905 	int ret;
1906 
1907 	if (!cda[CTA_NAT_DST] && !cda[CTA_NAT_SRC])
1908 		return 0;
1909 
1910 	ret = ctnetlink_parse_nat_setup(ct, NF_NAT_MANIP_DST,
1911 					cda[CTA_NAT_DST]);
1912 	if (ret < 0)
1913 		return ret;
1914 
1915 	return ctnetlink_parse_nat_setup(ct, NF_NAT_MANIP_SRC,
1916 					 cda[CTA_NAT_SRC]);
1917 #else
1918 	if (!cda[CTA_NAT_DST] && !cda[CTA_NAT_SRC])
1919 		return 0;
1920 	return -EOPNOTSUPP;
1921 #endif
1922 }
1923 
ctnetlink_change_helper(struct nf_conn * ct,const struct nlattr * const cda[])1924 static int ctnetlink_change_helper(struct nf_conn *ct,
1925 				   const struct nlattr * const cda[])
1926 {
1927 	struct nf_conntrack_helper *helper;
1928 	struct nf_conn_help *help = nfct_help(ct);
1929 	char *helpname = NULL;
1930 	struct nlattr *helpinfo = NULL;
1931 	int err;
1932 
1933 	err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
1934 	if (err < 0)
1935 		return err;
1936 
1937 	/* don't change helper of sibling connections */
1938 	if (ct->master) {
1939 		/* If we try to change the helper to the same thing twice,
1940 		 * treat the second attempt as a no-op instead of returning
1941 		 * an error.
1942 		 */
1943 		err = -EBUSY;
1944 		if (help) {
1945 			rcu_read_lock();
1946 			helper = rcu_dereference(help->helper);
1947 			if (helper && !strcmp(helper->name, helpname))
1948 				err = 0;
1949 			rcu_read_unlock();
1950 		}
1951 
1952 		return err;
1953 	}
1954 
1955 	if (!strcmp(helpname, "")) {
1956 		if (help && help->helper) {
1957 			/* we had a helper before ... */
1958 			nf_ct_remove_expectations(ct);
1959 			RCU_INIT_POINTER(help->helper, NULL);
1960 		}
1961 
1962 		return 0;
1963 	}
1964 
1965 	rcu_read_lock();
1966 	helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
1967 					    nf_ct_protonum(ct));
1968 	if (helper == NULL) {
1969 		rcu_read_unlock();
1970 		return -EOPNOTSUPP;
1971 	}
1972 
1973 	if (help) {
1974 		if (rcu_access_pointer(help->helper) == helper) {
1975 			/* update private helper data if allowed. */
1976 			if (helper->from_nlattr)
1977 				helper->from_nlattr(helpinfo, ct);
1978 			err = 0;
1979 		} else
1980 			err = -EBUSY;
1981 	} else {
1982 		/* we cannot set a helper for an existing conntrack */
1983 		err = -EOPNOTSUPP;
1984 	}
1985 
1986 	rcu_read_unlock();
1987 	return err;
1988 }
1989 
ctnetlink_change_timeout(struct nf_conn * ct,const struct nlattr * const cda[])1990 static int ctnetlink_change_timeout(struct nf_conn *ct,
1991 				    const struct nlattr * const cda[])
1992 {
1993 	return __nf_ct_change_timeout(ct, (u64)ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ);
1994 }
1995 
1996 #if defined(CONFIG_NF_CONNTRACK_MARK)
ctnetlink_change_mark(struct nf_conn * ct,const struct nlattr * const cda[])1997 static void ctnetlink_change_mark(struct nf_conn *ct,
1998 				    const struct nlattr * const cda[])
1999 {
2000 	u32 mark, newmark, mask = 0;
2001 
2002 	if (cda[CTA_MARK_MASK])
2003 		mask = ~ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
2004 
2005 	mark = ntohl(nla_get_be32(cda[CTA_MARK]));
2006 	newmark = (READ_ONCE(ct->mark) & mask) ^ mark;
2007 	if (newmark != READ_ONCE(ct->mark))
2008 		WRITE_ONCE(ct->mark, newmark);
2009 }
2010 #endif
2011 
2012 static const struct nla_policy protoinfo_policy[CTA_PROTOINFO_MAX+1] = {
2013 	[CTA_PROTOINFO_TCP]	= { .type = NLA_NESTED },
2014 	[CTA_PROTOINFO_DCCP]	= { .type = NLA_NESTED },
2015 	[CTA_PROTOINFO_SCTP]	= { .type = NLA_NESTED },
2016 };
2017 
ctnetlink_change_protoinfo(struct nf_conn * ct,const struct nlattr * const cda[])2018 static int ctnetlink_change_protoinfo(struct nf_conn *ct,
2019 				      const struct nlattr * const cda[])
2020 {
2021 	const struct nlattr *attr = cda[CTA_PROTOINFO];
2022 	const struct nf_conntrack_l4proto *l4proto;
2023 	struct nlattr *tb[CTA_PROTOINFO_MAX+1];
2024 	int err = 0;
2025 
2026 	err = nla_parse_nested_deprecated(tb, CTA_PROTOINFO_MAX, attr,
2027 					  protoinfo_policy, NULL);
2028 	if (err < 0)
2029 		return err;
2030 
2031 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
2032 	if (l4proto->from_nlattr)
2033 		err = l4proto->from_nlattr(tb, ct);
2034 
2035 	return err;
2036 }
2037 
2038 static const struct nla_policy seqadj_policy[CTA_SEQADJ_MAX+1] = {
2039 	[CTA_SEQADJ_CORRECTION_POS]	= { .type = NLA_U32 },
2040 	[CTA_SEQADJ_OFFSET_BEFORE]	= { .type = NLA_U32 },
2041 	[CTA_SEQADJ_OFFSET_AFTER]	= { .type = NLA_U32 },
2042 };
2043 
change_seq_adj(struct nf_ct_seqadj * seq,const struct nlattr * const attr)2044 static int change_seq_adj(struct nf_ct_seqadj *seq,
2045 			  const struct nlattr * const attr)
2046 {
2047 	int err;
2048 	struct nlattr *cda[CTA_SEQADJ_MAX+1];
2049 
2050 	err = nla_parse_nested_deprecated(cda, CTA_SEQADJ_MAX, attr,
2051 					  seqadj_policy, NULL);
2052 	if (err < 0)
2053 		return err;
2054 
2055 	if (!cda[CTA_SEQADJ_CORRECTION_POS])
2056 		return -EINVAL;
2057 
2058 	seq->correction_pos =
2059 		ntohl(nla_get_be32(cda[CTA_SEQADJ_CORRECTION_POS]));
2060 
2061 	if (!cda[CTA_SEQADJ_OFFSET_BEFORE])
2062 		return -EINVAL;
2063 
2064 	seq->offset_before =
2065 		ntohl(nla_get_be32(cda[CTA_SEQADJ_OFFSET_BEFORE]));
2066 
2067 	if (!cda[CTA_SEQADJ_OFFSET_AFTER])
2068 		return -EINVAL;
2069 
2070 	seq->offset_after =
2071 		ntohl(nla_get_be32(cda[CTA_SEQADJ_OFFSET_AFTER]));
2072 
2073 	return 0;
2074 }
2075 
2076 static int
ctnetlink_change_seq_adj(struct nf_conn * ct,const struct nlattr * const cda[])2077 ctnetlink_change_seq_adj(struct nf_conn *ct,
2078 			 const struct nlattr * const cda[])
2079 {
2080 	struct nf_conn_seqadj *seqadj = nfct_seqadj(ct);
2081 	int ret = 0;
2082 
2083 	if (!seqadj)
2084 		return 0;
2085 
2086 	spin_lock_bh(&ct->lock);
2087 	if (cda[CTA_SEQ_ADJ_ORIG]) {
2088 		ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_ORIGINAL],
2089 				     cda[CTA_SEQ_ADJ_ORIG]);
2090 		if (ret < 0)
2091 			goto err;
2092 
2093 		set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
2094 	}
2095 
2096 	if (cda[CTA_SEQ_ADJ_REPLY]) {
2097 		ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_REPLY],
2098 				     cda[CTA_SEQ_ADJ_REPLY]);
2099 		if (ret < 0)
2100 			goto err;
2101 
2102 		set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
2103 	}
2104 
2105 	spin_unlock_bh(&ct->lock);
2106 	return 0;
2107 err:
2108 	spin_unlock_bh(&ct->lock);
2109 	return ret;
2110 }
2111 
2112 static const struct nla_policy synproxy_policy[CTA_SYNPROXY_MAX + 1] = {
2113 	[CTA_SYNPROXY_ISN]	= { .type = NLA_U32 },
2114 	[CTA_SYNPROXY_ITS]	= { .type = NLA_U32 },
2115 	[CTA_SYNPROXY_TSOFF]	= { .type = NLA_U32 },
2116 };
2117 
ctnetlink_change_synproxy(struct nf_conn * ct,const struct nlattr * const cda[])2118 static int ctnetlink_change_synproxy(struct nf_conn *ct,
2119 				     const struct nlattr * const cda[])
2120 {
2121 	struct nf_conn_synproxy *synproxy = nfct_synproxy(ct);
2122 	struct nlattr *tb[CTA_SYNPROXY_MAX + 1];
2123 	int err;
2124 
2125 	if (!synproxy)
2126 		return 0;
2127 
2128 	err = nla_parse_nested_deprecated(tb, CTA_SYNPROXY_MAX,
2129 					  cda[CTA_SYNPROXY], synproxy_policy,
2130 					  NULL);
2131 	if (err < 0)
2132 		return err;
2133 
2134 	if (!tb[CTA_SYNPROXY_ISN] ||
2135 	    !tb[CTA_SYNPROXY_ITS] ||
2136 	    !tb[CTA_SYNPROXY_TSOFF])
2137 		return -EINVAL;
2138 
2139 	synproxy->isn = ntohl(nla_get_be32(tb[CTA_SYNPROXY_ISN]));
2140 	synproxy->its = ntohl(nla_get_be32(tb[CTA_SYNPROXY_ITS]));
2141 	synproxy->tsoff = ntohl(nla_get_be32(tb[CTA_SYNPROXY_TSOFF]));
2142 
2143 	return 0;
2144 }
2145 
2146 static int
ctnetlink_attach_labels(struct nf_conn * ct,const struct nlattr * const cda[])2147 ctnetlink_attach_labels(struct nf_conn *ct, const struct nlattr * const cda[])
2148 {
2149 #ifdef CONFIG_NF_CONNTRACK_LABELS
2150 	size_t len = nla_len(cda[CTA_LABELS]);
2151 	const void *mask = cda[CTA_LABELS_MASK];
2152 
2153 	if (len & (sizeof(u32)-1)) /* must be multiple of u32 */
2154 		return -EINVAL;
2155 
2156 	if (mask) {
2157 		if (nla_len(cda[CTA_LABELS_MASK]) == 0 ||
2158 		    nla_len(cda[CTA_LABELS_MASK]) != len)
2159 			return -EINVAL;
2160 		mask = nla_data(cda[CTA_LABELS_MASK]);
2161 	}
2162 
2163 	len /= sizeof(u32);
2164 
2165 	return nf_connlabels_replace(ct, nla_data(cda[CTA_LABELS]), mask, len);
2166 #else
2167 	return -EOPNOTSUPP;
2168 #endif
2169 }
2170 
2171 static int
ctnetlink_change_conntrack(struct nf_conn * ct,const struct nlattr * const cda[])2172 ctnetlink_change_conntrack(struct nf_conn *ct,
2173 			   const struct nlattr * const cda[])
2174 {
2175 	int err;
2176 
2177 	/* only allow NAT changes and master assignation for new conntracks */
2178 	if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST] || cda[CTA_TUPLE_MASTER])
2179 		return -EOPNOTSUPP;
2180 
2181 	if (cda[CTA_HELP]) {
2182 		err = ctnetlink_change_helper(ct, cda);
2183 		if (err < 0)
2184 			return err;
2185 	}
2186 
2187 	if (cda[CTA_TIMEOUT]) {
2188 		err = ctnetlink_change_timeout(ct, cda);
2189 		if (err < 0)
2190 			return err;
2191 	}
2192 
2193 	if (cda[CTA_STATUS]) {
2194 		err = ctnetlink_change_status(ct, cda);
2195 		if (err < 0)
2196 			return err;
2197 	}
2198 
2199 	if (cda[CTA_PROTOINFO]) {
2200 		err = ctnetlink_change_protoinfo(ct, cda);
2201 		if (err < 0)
2202 			return err;
2203 	}
2204 
2205 #if defined(CONFIG_NF_CONNTRACK_MARK)
2206 	if (cda[CTA_MARK])
2207 		ctnetlink_change_mark(ct, cda);
2208 #endif
2209 
2210 	if (cda[CTA_SEQ_ADJ_ORIG] || cda[CTA_SEQ_ADJ_REPLY]) {
2211 		err = ctnetlink_change_seq_adj(ct, cda);
2212 		if (err < 0)
2213 			return err;
2214 	}
2215 
2216 	if (cda[CTA_SYNPROXY]) {
2217 		err = ctnetlink_change_synproxy(ct, cda);
2218 		if (err < 0)
2219 			return err;
2220 	}
2221 
2222 	if (cda[CTA_LABELS]) {
2223 		err = ctnetlink_attach_labels(ct, cda);
2224 		if (err < 0)
2225 			return err;
2226 	}
2227 
2228 	return 0;
2229 }
2230 
2231 static struct nf_conn *
ctnetlink_create_conntrack(struct net * net,const struct nf_conntrack_zone * zone,const struct nlattr * const cda[],struct nf_conntrack_tuple * otuple,struct nf_conntrack_tuple * rtuple,u8 u3)2232 ctnetlink_create_conntrack(struct net *net,
2233 			   const struct nf_conntrack_zone *zone,
2234 			   const struct nlattr * const cda[],
2235 			   struct nf_conntrack_tuple *otuple,
2236 			   struct nf_conntrack_tuple *rtuple,
2237 			   u8 u3)
2238 {
2239 	struct nf_conn *ct;
2240 	int err = -EINVAL;
2241 	struct nf_conntrack_helper *helper;
2242 	struct nf_conn_tstamp *tstamp;
2243 	u64 timeout;
2244 
2245 	ct = nf_conntrack_alloc(net, zone, otuple, rtuple, GFP_ATOMIC);
2246 	if (IS_ERR(ct))
2247 		return ERR_PTR(-ENOMEM);
2248 
2249 	if (!cda[CTA_TIMEOUT])
2250 		goto err1;
2251 
2252 	rcu_read_lock();
2253  	if (cda[CTA_HELP]) {
2254 		char *helpname = NULL;
2255 		struct nlattr *helpinfo = NULL;
2256 
2257 		err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
2258  		if (err < 0)
2259 			goto err2;
2260 
2261 		helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
2262 						    nf_ct_protonum(ct));
2263 		if (helper == NULL) {
2264 			rcu_read_unlock();
2265 #ifdef CONFIG_MODULES
2266 			if (request_module("nfct-helper-%s", helpname) < 0) {
2267 				err = -EOPNOTSUPP;
2268 				goto err1;
2269 			}
2270 
2271 			rcu_read_lock();
2272 			helper = __nf_conntrack_helper_find(helpname,
2273 							    nf_ct_l3num(ct),
2274 							    nf_ct_protonum(ct));
2275 			if (helper) {
2276 				err = -EAGAIN;
2277 				goto err2;
2278 			}
2279 			rcu_read_unlock();
2280 #endif
2281 			err = -EOPNOTSUPP;
2282 			goto err1;
2283 		} else {
2284 			struct nf_conn_help *help;
2285 
2286 			help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
2287 			if (help == NULL) {
2288 				err = -ENOMEM;
2289 				goto err2;
2290 			}
2291 			/* set private helper data if allowed. */
2292 			if (helper->from_nlattr)
2293 				helper->from_nlattr(helpinfo, ct);
2294 
2295 			/* disable helper auto-assignment for this entry */
2296 			ct->status |= IPS_HELPER;
2297 			RCU_INIT_POINTER(help->helper, helper);
2298 		}
2299 	}
2300 
2301 	err = ctnetlink_setup_nat(ct, cda);
2302 	if (err < 0)
2303 		goto err2;
2304 
2305 	nf_ct_acct_ext_add(ct, GFP_ATOMIC);
2306 	nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
2307 	nf_ct_ecache_ext_add(ct, 0, 0, GFP_ATOMIC);
2308 	nf_ct_labels_ext_add(ct);
2309 	nfct_seqadj_ext_add(ct);
2310 	nfct_synproxy_ext_add(ct);
2311 
2312 	/* we must add conntrack extensions before confirmation. */
2313 	ct->status |= IPS_CONFIRMED;
2314 
2315 	timeout = (u64)ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ;
2316 	__nf_ct_set_timeout(ct, timeout);
2317 
2318 	if (cda[CTA_STATUS]) {
2319 		err = ctnetlink_change_status(ct, cda);
2320 		if (err < 0)
2321 			goto err2;
2322 	}
2323 
2324 	if (cda[CTA_SEQ_ADJ_ORIG] || cda[CTA_SEQ_ADJ_REPLY]) {
2325 		err = ctnetlink_change_seq_adj(ct, cda);
2326 		if (err < 0)
2327 			goto err2;
2328 	}
2329 
2330 	memset(&ct->proto, 0, sizeof(ct->proto));
2331 	if (cda[CTA_PROTOINFO]) {
2332 		err = ctnetlink_change_protoinfo(ct, cda);
2333 		if (err < 0)
2334 			goto err2;
2335 	}
2336 
2337 	if (cda[CTA_SYNPROXY]) {
2338 		err = ctnetlink_change_synproxy(ct, cda);
2339 		if (err < 0)
2340 			goto err2;
2341 	}
2342 
2343 #if defined(CONFIG_NF_CONNTRACK_MARK)
2344 	if (cda[CTA_MARK])
2345 		ctnetlink_change_mark(ct, cda);
2346 #endif
2347 
2348 	/* setup master conntrack: this is a confirmed expectation */
2349 	if (cda[CTA_TUPLE_MASTER]) {
2350 		struct nf_conntrack_tuple master;
2351 		struct nf_conntrack_tuple_hash *master_h;
2352 		struct nf_conn *master_ct;
2353 
2354 		err = ctnetlink_parse_tuple(cda, &master, CTA_TUPLE_MASTER,
2355 					    u3, NULL);
2356 		if (err < 0)
2357 			goto err2;
2358 
2359 		master_h = nf_conntrack_find_get(net, zone, &master);
2360 		if (master_h == NULL) {
2361 			err = -ENOENT;
2362 			goto err2;
2363 		}
2364 		master_ct = nf_ct_tuplehash_to_ctrack(master_h);
2365 		__set_bit(IPS_EXPECTED_BIT, &ct->status);
2366 		ct->master = master_ct;
2367 	}
2368 	tstamp = nf_conn_tstamp_find(ct);
2369 	if (tstamp)
2370 		tstamp->start = ktime_get_real_ns();
2371 
2372 	err = nf_conntrack_hash_check_insert(ct);
2373 	if (err < 0)
2374 		goto err3;
2375 
2376 	rcu_read_unlock();
2377 
2378 	return ct;
2379 
2380 err3:
2381 	if (ct->master)
2382 		nf_ct_put(ct->master);
2383 err2:
2384 	rcu_read_unlock();
2385 err1:
2386 	nf_conntrack_free(ct);
2387 	return ERR_PTR(err);
2388 }
2389 
ctnetlink_new_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2390 static int ctnetlink_new_conntrack(struct sk_buff *skb,
2391 				   const struct nfnl_info *info,
2392 				   const struct nlattr * const cda[])
2393 {
2394 	struct nf_conntrack_tuple otuple, rtuple;
2395 	struct nf_conntrack_tuple_hash *h = NULL;
2396 	u_int8_t u3 = info->nfmsg->nfgen_family;
2397 	struct nf_conntrack_zone zone;
2398 	struct nf_conn *ct;
2399 	int err;
2400 
2401 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
2402 	if (err < 0)
2403 		return err;
2404 
2405 	if (cda[CTA_TUPLE_ORIG]) {
2406 		err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG,
2407 					    u3, &zone);
2408 		if (err < 0)
2409 			return err;
2410 	}
2411 
2412 	if (cda[CTA_TUPLE_REPLY]) {
2413 		err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY,
2414 					    u3, &zone);
2415 		if (err < 0)
2416 			return err;
2417 	}
2418 
2419 	if (cda[CTA_TUPLE_ORIG])
2420 		h = nf_conntrack_find_get(info->net, &zone, &otuple);
2421 	else if (cda[CTA_TUPLE_REPLY])
2422 		h = nf_conntrack_find_get(info->net, &zone, &rtuple);
2423 
2424 	if (h == NULL) {
2425 		err = -ENOENT;
2426 		if (info->nlh->nlmsg_flags & NLM_F_CREATE) {
2427 			enum ip_conntrack_events events;
2428 
2429 			if (!cda[CTA_TUPLE_ORIG] || !cda[CTA_TUPLE_REPLY])
2430 				return -EINVAL;
2431 			if (otuple.dst.protonum != rtuple.dst.protonum)
2432 				return -EINVAL;
2433 
2434 			ct = ctnetlink_create_conntrack(info->net, &zone, cda,
2435 							&otuple, &rtuple, u3);
2436 			if (IS_ERR(ct))
2437 				return PTR_ERR(ct);
2438 
2439 			err = 0;
2440 			if (test_bit(IPS_EXPECTED_BIT, &ct->status))
2441 				events = 1 << IPCT_RELATED;
2442 			else
2443 				events = 1 << IPCT_NEW;
2444 
2445 			if (cda[CTA_LABELS] &&
2446 			    ctnetlink_attach_labels(ct, cda) == 0)
2447 				events |= (1 << IPCT_LABEL);
2448 
2449 			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
2450 						      (1 << IPCT_ASSURED) |
2451 						      (1 << IPCT_HELPER) |
2452 						      (1 << IPCT_PROTOINFO) |
2453 						      (1 << IPCT_SEQADJ) |
2454 						      (1 << IPCT_MARK) |
2455 						      (1 << IPCT_SYNPROXY) |
2456 						      events,
2457 						      ct, NETLINK_CB(skb).portid,
2458 						      nlmsg_report(info->nlh));
2459 			nf_ct_put(ct);
2460 		}
2461 
2462 		return err;
2463 	}
2464 	/* implicit 'else' */
2465 
2466 	err = -EEXIST;
2467 	ct = nf_ct_tuplehash_to_ctrack(h);
2468 	if (!(info->nlh->nlmsg_flags & NLM_F_EXCL)) {
2469 		err = ctnetlink_change_conntrack(ct, cda);
2470 		if (err == 0) {
2471 			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
2472 						      (1 << IPCT_ASSURED) |
2473 						      (1 << IPCT_HELPER) |
2474 						      (1 << IPCT_LABEL) |
2475 						      (1 << IPCT_PROTOINFO) |
2476 						      (1 << IPCT_SEQADJ) |
2477 						      (1 << IPCT_MARK) |
2478 						      (1 << IPCT_SYNPROXY),
2479 						      ct, NETLINK_CB(skb).portid,
2480 						      nlmsg_report(info->nlh));
2481 		}
2482 	}
2483 
2484 	nf_ct_put(ct);
2485 	return err;
2486 }
2487 
2488 static int
ctnetlink_ct_stat_cpu_fill_info(struct sk_buff * skb,u32 portid,u32 seq,__u16 cpu,const struct ip_conntrack_stat * st)2489 ctnetlink_ct_stat_cpu_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
2490 				__u16 cpu, const struct ip_conntrack_stat *st)
2491 {
2492 	struct nlmsghdr *nlh;
2493 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
2494 
2495 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK,
2496 			      IPCTNL_MSG_CT_GET_STATS_CPU);
2497 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
2498 			   NFNETLINK_V0, htons(cpu));
2499 	if (!nlh)
2500 		goto nlmsg_failure;
2501 
2502 	if (nla_put_be32(skb, CTA_STATS_FOUND, htonl(st->found)) ||
2503 	    nla_put_be32(skb, CTA_STATS_INVALID, htonl(st->invalid)) ||
2504 	    nla_put_be32(skb, CTA_STATS_INSERT, htonl(st->insert)) ||
2505 	    nla_put_be32(skb, CTA_STATS_INSERT_FAILED,
2506 				htonl(st->insert_failed)) ||
2507 	    nla_put_be32(skb, CTA_STATS_DROP, htonl(st->drop)) ||
2508 	    nla_put_be32(skb, CTA_STATS_EARLY_DROP, htonl(st->early_drop)) ||
2509 	    nla_put_be32(skb, CTA_STATS_ERROR, htonl(st->error)) ||
2510 	    nla_put_be32(skb, CTA_STATS_SEARCH_RESTART,
2511 				htonl(st->search_restart)) ||
2512 	    nla_put_be32(skb, CTA_STATS_CLASH_RESOLVE,
2513 				htonl(st->clash_resolve)) ||
2514 	    nla_put_be32(skb, CTA_STATS_CHAIN_TOOLONG,
2515 			 htonl(st->chaintoolong)))
2516 		goto nla_put_failure;
2517 
2518 	nlmsg_end(skb, nlh);
2519 	return skb->len;
2520 
2521 nla_put_failure:
2522 nlmsg_failure:
2523 	nlmsg_cancel(skb, nlh);
2524 	return -1;
2525 }
2526 
2527 static int
ctnetlink_ct_stat_cpu_dump(struct sk_buff * skb,struct netlink_callback * cb)2528 ctnetlink_ct_stat_cpu_dump(struct sk_buff *skb, struct netlink_callback *cb)
2529 {
2530 	int cpu;
2531 	struct net *net = sock_net(skb->sk);
2532 
2533 	if (cb->args[0] == nr_cpu_ids)
2534 		return 0;
2535 
2536 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
2537 		const struct ip_conntrack_stat *st;
2538 
2539 		if (!cpu_possible(cpu))
2540 			continue;
2541 
2542 		st = per_cpu_ptr(net->ct.stat, cpu);
2543 		if (ctnetlink_ct_stat_cpu_fill_info(skb,
2544 						    NETLINK_CB(cb->skb).portid,
2545 						    cb->nlh->nlmsg_seq,
2546 						    cpu, st) < 0)
2547 				break;
2548 	}
2549 	cb->args[0] = cpu;
2550 
2551 	return skb->len;
2552 }
2553 
ctnetlink_stat_ct_cpu(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2554 static int ctnetlink_stat_ct_cpu(struct sk_buff *skb,
2555 				 const struct nfnl_info *info,
2556 				 const struct nlattr * const cda[])
2557 {
2558 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
2559 		struct netlink_dump_control c = {
2560 			.dump = ctnetlink_ct_stat_cpu_dump,
2561 		};
2562 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
2563 	}
2564 
2565 	return 0;
2566 }
2567 
2568 static int
ctnetlink_stat_ct_fill_info(struct sk_buff * skb,u32 portid,u32 seq,u32 type,struct net * net)2569 ctnetlink_stat_ct_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
2570 			    struct net *net)
2571 {
2572 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
2573 	unsigned int nr_conntracks;
2574 	struct nlmsghdr *nlh;
2575 
2576 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_GET_STATS);
2577 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
2578 			   NFNETLINK_V0, 0);
2579 	if (!nlh)
2580 		goto nlmsg_failure;
2581 
2582 	nr_conntracks = nf_conntrack_count(net);
2583 	if (nla_put_be32(skb, CTA_STATS_GLOBAL_ENTRIES, htonl(nr_conntracks)))
2584 		goto nla_put_failure;
2585 
2586 	if (nla_put_be32(skb, CTA_STATS_GLOBAL_MAX_ENTRIES, htonl(nf_conntrack_max)))
2587 		goto nla_put_failure;
2588 
2589 	nlmsg_end(skb, nlh);
2590 	return skb->len;
2591 
2592 nla_put_failure:
2593 nlmsg_failure:
2594 	nlmsg_cancel(skb, nlh);
2595 	return -1;
2596 }
2597 
ctnetlink_stat_ct(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2598 static int ctnetlink_stat_ct(struct sk_buff *skb, const struct nfnl_info *info,
2599 			     const struct nlattr * const cda[])
2600 {
2601 	struct sk_buff *skb2;
2602 	int err;
2603 
2604 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
2605 	if (skb2 == NULL)
2606 		return -ENOMEM;
2607 
2608 	err = ctnetlink_stat_ct_fill_info(skb2, NETLINK_CB(skb).portid,
2609 					  info->nlh->nlmsg_seq,
2610 					  NFNL_MSG_TYPE(info->nlh->nlmsg_type),
2611 					  sock_net(skb->sk));
2612 	if (err <= 0) {
2613 		kfree_skb(skb2);
2614 		return -ENOMEM;
2615 	}
2616 
2617 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
2618 }
2619 
2620 static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
2621 	[CTA_EXPECT_MASTER]	= { .type = NLA_NESTED },
2622 	[CTA_EXPECT_TUPLE]	= { .type = NLA_NESTED },
2623 	[CTA_EXPECT_MASK]	= { .type = NLA_NESTED },
2624 	[CTA_EXPECT_TIMEOUT]	= { .type = NLA_U32 },
2625 	[CTA_EXPECT_ID]		= { .type = NLA_U32 },
2626 	[CTA_EXPECT_HELP_NAME]	= { .type = NLA_NUL_STRING,
2627 				    .len = NF_CT_HELPER_NAME_LEN - 1 },
2628 	[CTA_EXPECT_ZONE]	= { .type = NLA_U16 },
2629 	[CTA_EXPECT_FLAGS]	= { .type = NLA_U32 },
2630 	[CTA_EXPECT_CLASS]	= { .type = NLA_U32 },
2631 	[CTA_EXPECT_NAT]	= { .type = NLA_NESTED },
2632 	[CTA_EXPECT_FN]		= { .type = NLA_NUL_STRING },
2633 };
2634 
2635 static struct nf_conntrack_expect *
2636 ctnetlink_alloc_expect(const struct nlattr *const cda[], struct nf_conn *ct,
2637 		       struct nf_conntrack_helper *helper,
2638 		       struct nf_conntrack_tuple *tuple,
2639 		       struct nf_conntrack_tuple *mask);
2640 
2641 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
2642 static size_t
ctnetlink_glue_build_size(const struct nf_conn * ct)2643 ctnetlink_glue_build_size(const struct nf_conn *ct)
2644 {
2645 	return 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
2646 	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
2647 	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
2648 	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
2649 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
2650 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
2651 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
2652 	       + nla_total_size(0) /* CTA_PROTOINFO */
2653 	       + nla_total_size(0) /* CTA_HELP */
2654 	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
2655 	       + ctnetlink_secctx_size(ct)
2656 	       + ctnetlink_acct_size(ct)
2657 	       + ctnetlink_timestamp_size(ct)
2658 #if IS_ENABLED(CONFIG_NF_NAT)
2659 	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
2660 	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
2661 #endif
2662 #ifdef CONFIG_NF_CONNTRACK_MARK
2663 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
2664 #endif
2665 #ifdef CONFIG_NF_CONNTRACK_ZONES
2666 	       + nla_total_size(sizeof(u_int16_t)) /* CTA_ZONE|CTA_TUPLE_ZONE */
2667 #endif
2668 	       + ctnetlink_proto_size(ct)
2669 	       ;
2670 }
2671 
__ctnetlink_glue_build(struct sk_buff * skb,struct nf_conn * ct)2672 static int __ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct)
2673 {
2674 	const struct nf_conntrack_zone *zone;
2675 	struct nlattr *nest_parms;
2676 
2677 	zone = nf_ct_zone(ct);
2678 
2679 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
2680 	if (!nest_parms)
2681 		goto nla_put_failure;
2682 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
2683 		goto nla_put_failure;
2684 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
2685 				   NF_CT_ZONE_DIR_ORIG) < 0)
2686 		goto nla_put_failure;
2687 	nla_nest_end(skb, nest_parms);
2688 
2689 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
2690 	if (!nest_parms)
2691 		goto nla_put_failure;
2692 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
2693 		goto nla_put_failure;
2694 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
2695 				   NF_CT_ZONE_DIR_REPL) < 0)
2696 		goto nla_put_failure;
2697 	nla_nest_end(skb, nest_parms);
2698 
2699 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
2700 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
2701 		goto nla_put_failure;
2702 
2703 	if (ctnetlink_dump_id(skb, ct) < 0)
2704 		goto nla_put_failure;
2705 
2706 	if (ctnetlink_dump_status(skb, ct) < 0)
2707 		goto nla_put_failure;
2708 
2709 	if (ctnetlink_dump_timeout(skb, ct, false) < 0)
2710 		goto nla_put_failure;
2711 
2712 	if (ctnetlink_dump_protoinfo(skb, ct, false) < 0)
2713 		goto nla_put_failure;
2714 
2715 	if (ctnetlink_dump_acct(skb, ct, IPCTNL_MSG_CT_GET) < 0 ||
2716 	    ctnetlink_dump_timestamp(skb, ct) < 0)
2717 		goto nla_put_failure;
2718 
2719 	if (ctnetlink_dump_helpinfo(skb, ct) < 0)
2720 		goto nla_put_failure;
2721 
2722 #ifdef CONFIG_NF_CONNTRACK_SECMARK
2723 	if (ct->secmark && ctnetlink_dump_secctx(skb, ct) < 0)
2724 		goto nla_put_failure;
2725 #endif
2726 	if (ct->master && ctnetlink_dump_master(skb, ct) < 0)
2727 		goto nla_put_failure;
2728 
2729 	if ((ct->status & IPS_SEQ_ADJUST) &&
2730 	    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
2731 		goto nla_put_failure;
2732 
2733 	if (ctnetlink_dump_ct_synproxy(skb, ct) < 0)
2734 		goto nla_put_failure;
2735 
2736 #ifdef CONFIG_NF_CONNTRACK_MARK
2737 	if (ctnetlink_dump_mark(skb, ct, true) < 0)
2738 		goto nla_put_failure;
2739 #endif
2740 	if (ctnetlink_dump_labels(skb, ct) < 0)
2741 		goto nla_put_failure;
2742 	return 0;
2743 
2744 nla_put_failure:
2745 	return -ENOSPC;
2746 }
2747 
2748 static int
ctnetlink_glue_build(struct sk_buff * skb,struct nf_conn * ct,enum ip_conntrack_info ctinfo,u_int16_t ct_attr,u_int16_t ct_info_attr)2749 ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct,
2750 		     enum ip_conntrack_info ctinfo,
2751 		     u_int16_t ct_attr, u_int16_t ct_info_attr)
2752 {
2753 	struct nlattr *nest_parms;
2754 
2755 	nest_parms = nla_nest_start(skb, ct_attr);
2756 	if (!nest_parms)
2757 		goto nla_put_failure;
2758 
2759 	if (__ctnetlink_glue_build(skb, ct) < 0)
2760 		goto nla_put_failure;
2761 
2762 	nla_nest_end(skb, nest_parms);
2763 
2764 	if (nla_put_be32(skb, ct_info_attr, htonl(ctinfo)))
2765 		goto nla_put_failure;
2766 
2767 	return 0;
2768 
2769 nla_put_failure:
2770 	return -ENOSPC;
2771 }
2772 
2773 static int
ctnetlink_update_status(struct nf_conn * ct,const struct nlattr * const cda[])2774 ctnetlink_update_status(struct nf_conn *ct, const struct nlattr * const cda[])
2775 {
2776 	unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
2777 	unsigned long d = ct->status ^ status;
2778 
2779 	if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
2780 		/* SEEN_REPLY bit can only be set */
2781 		return -EBUSY;
2782 
2783 	if (d & IPS_ASSURED && !(status & IPS_ASSURED))
2784 		/* ASSURED bit can only be set */
2785 		return -EBUSY;
2786 
2787 	/* This check is less strict than ctnetlink_change_status()
2788 	 * because callers often flip IPS_EXPECTED bits when sending
2789 	 * an NFQA_CT attribute to the kernel.  So ignore the
2790 	 * unchangeable bits but do not error out. Also user programs
2791 	 * are allowed to clear the bits that they are allowed to change.
2792 	 */
2793 	__nf_ct_change_status(ct, status, ~status);
2794 	return 0;
2795 }
2796 
2797 static int
ctnetlink_glue_parse_ct(const struct nlattr * cda[],struct nf_conn * ct)2798 ctnetlink_glue_parse_ct(const struct nlattr *cda[], struct nf_conn *ct)
2799 {
2800 	int err;
2801 
2802 	if (cda[CTA_TIMEOUT]) {
2803 		err = ctnetlink_change_timeout(ct, cda);
2804 		if (err < 0)
2805 			return err;
2806 	}
2807 	if (cda[CTA_STATUS]) {
2808 		err = ctnetlink_update_status(ct, cda);
2809 		if (err < 0)
2810 			return err;
2811 	}
2812 	if (cda[CTA_HELP]) {
2813 		err = ctnetlink_change_helper(ct, cda);
2814 		if (err < 0)
2815 			return err;
2816 	}
2817 	if (cda[CTA_LABELS]) {
2818 		err = ctnetlink_attach_labels(ct, cda);
2819 		if (err < 0)
2820 			return err;
2821 	}
2822 #if defined(CONFIG_NF_CONNTRACK_MARK)
2823 	if (cda[CTA_MARK]) {
2824 		ctnetlink_change_mark(ct, cda);
2825 	}
2826 #endif
2827 	return 0;
2828 }
2829 
2830 static int
ctnetlink_glue_parse(const struct nlattr * attr,struct nf_conn * ct)2831 ctnetlink_glue_parse(const struct nlattr *attr, struct nf_conn *ct)
2832 {
2833 	struct nlattr *cda[CTA_MAX+1];
2834 	int ret;
2835 
2836 	ret = nla_parse_nested_deprecated(cda, CTA_MAX, attr, ct_nla_policy,
2837 					  NULL);
2838 	if (ret < 0)
2839 		return ret;
2840 
2841 	return ctnetlink_glue_parse_ct((const struct nlattr **)cda, ct);
2842 }
2843 
ctnetlink_glue_exp_parse(const struct nlattr * const * cda,const struct nf_conn * ct,struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple * mask)2844 static int ctnetlink_glue_exp_parse(const struct nlattr * const *cda,
2845 				    const struct nf_conn *ct,
2846 				    struct nf_conntrack_tuple *tuple,
2847 				    struct nf_conntrack_tuple *mask)
2848 {
2849 	int err;
2850 
2851 	err = ctnetlink_parse_tuple(cda, tuple, CTA_EXPECT_TUPLE,
2852 				    nf_ct_l3num(ct), NULL);
2853 	if (err < 0)
2854 		return err;
2855 
2856 	return ctnetlink_parse_tuple(cda, mask, CTA_EXPECT_MASK,
2857 				     nf_ct_l3num(ct), NULL);
2858 }
2859 
2860 static int
ctnetlink_glue_attach_expect(const struct nlattr * attr,struct nf_conn * ct,u32 portid,u32 report)2861 ctnetlink_glue_attach_expect(const struct nlattr *attr, struct nf_conn *ct,
2862 			     u32 portid, u32 report)
2863 {
2864 	struct nlattr *cda[CTA_EXPECT_MAX+1];
2865 	struct nf_conntrack_tuple tuple, mask;
2866 	struct nf_conntrack_helper *helper = NULL;
2867 	struct nf_conntrack_expect *exp;
2868 	int err;
2869 
2870 	err = nla_parse_nested_deprecated(cda, CTA_EXPECT_MAX, attr,
2871 					  exp_nla_policy, NULL);
2872 	if (err < 0)
2873 		return err;
2874 
2875 	err = ctnetlink_glue_exp_parse((const struct nlattr * const *)cda,
2876 				       ct, &tuple, &mask);
2877 	if (err < 0)
2878 		return err;
2879 
2880 	if (cda[CTA_EXPECT_HELP_NAME]) {
2881 		const char *helpname = nla_data(cda[CTA_EXPECT_HELP_NAME]);
2882 
2883 		helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
2884 						    nf_ct_protonum(ct));
2885 		if (helper == NULL)
2886 			return -EOPNOTSUPP;
2887 	}
2888 
2889 	exp = ctnetlink_alloc_expect((const struct nlattr * const *)cda, ct,
2890 				     helper, &tuple, &mask);
2891 	if (IS_ERR(exp))
2892 		return PTR_ERR(exp);
2893 
2894 	err = nf_ct_expect_related_report(exp, portid, report, 0);
2895 	nf_ct_expect_put(exp);
2896 	return err;
2897 }
2898 
ctnetlink_glue_seqadj(struct sk_buff * skb,struct nf_conn * ct,enum ip_conntrack_info ctinfo,int diff)2899 static void ctnetlink_glue_seqadj(struct sk_buff *skb, struct nf_conn *ct,
2900 				  enum ip_conntrack_info ctinfo, int diff)
2901 {
2902 	if (!(ct->status & IPS_NAT_MASK))
2903 		return;
2904 
2905 	nf_ct_tcp_seqadj_set(skb, ct, ctinfo, diff);
2906 }
2907 
2908 static const struct nfnl_ct_hook ctnetlink_glue_hook = {
2909 	.build_size	= ctnetlink_glue_build_size,
2910 	.build		= ctnetlink_glue_build,
2911 	.parse		= ctnetlink_glue_parse,
2912 	.attach_expect	= ctnetlink_glue_attach_expect,
2913 	.seq_adjust	= ctnetlink_glue_seqadj,
2914 };
2915 #endif /* CONFIG_NETFILTER_NETLINK_GLUE_CT */
2916 
2917 /***********************************************************************
2918  * EXPECT
2919  ***********************************************************************/
2920 
ctnetlink_exp_dump_tuple(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,u32 type)2921 static int ctnetlink_exp_dump_tuple(struct sk_buff *skb,
2922 				    const struct nf_conntrack_tuple *tuple,
2923 				    u32 type)
2924 {
2925 	struct nlattr *nest_parms;
2926 
2927 	nest_parms = nla_nest_start(skb, type);
2928 	if (!nest_parms)
2929 		goto nla_put_failure;
2930 	if (ctnetlink_dump_tuples(skb, tuple) < 0)
2931 		goto nla_put_failure;
2932 	nla_nest_end(skb, nest_parms);
2933 
2934 	return 0;
2935 
2936 nla_put_failure:
2937 	return -1;
2938 }
2939 
ctnetlink_exp_dump_mask(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_tuple_mask * mask)2940 static int ctnetlink_exp_dump_mask(struct sk_buff *skb,
2941 				   const struct nf_conntrack_tuple *tuple,
2942 				   const struct nf_conntrack_tuple_mask *mask)
2943 {
2944 	const struct nf_conntrack_l4proto *l4proto;
2945 	struct nf_conntrack_tuple m;
2946 	struct nlattr *nest_parms;
2947 	int ret;
2948 
2949 	memset(&m, 0xFF, sizeof(m));
2950 	memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
2951 	m.src.u.all = mask->src.u.all;
2952 	m.src.l3num = tuple->src.l3num;
2953 	m.dst.protonum = tuple->dst.protonum;
2954 
2955 	nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK);
2956 	if (!nest_parms)
2957 		goto nla_put_failure;
2958 
2959 	rcu_read_lock();
2960 	ret = ctnetlink_dump_tuples_ip(skb, &m);
2961 	if (ret >= 0) {
2962 		l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
2963 		ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
2964 	}
2965 	rcu_read_unlock();
2966 
2967 	if (unlikely(ret < 0))
2968 		goto nla_put_failure;
2969 
2970 	nla_nest_end(skb, nest_parms);
2971 
2972 	return 0;
2973 
2974 nla_put_failure:
2975 	return -1;
2976 }
2977 
2978 #if IS_ENABLED(CONFIG_NF_NAT)
2979 static const union nf_inet_addr any_addr;
2980 #endif
2981 
nf_expect_get_id(const struct nf_conntrack_expect * exp)2982 static __be32 nf_expect_get_id(const struct nf_conntrack_expect *exp)
2983 {
2984 	static siphash_aligned_key_t exp_id_seed;
2985 	unsigned long a, b, c, d;
2986 
2987 	net_get_random_once(&exp_id_seed, sizeof(exp_id_seed));
2988 
2989 	a = (unsigned long)exp;
2990 	b = (unsigned long)exp->helper;
2991 	c = (unsigned long)exp->master;
2992 	d = (unsigned long)siphash(&exp->tuple, sizeof(exp->tuple), &exp_id_seed);
2993 
2994 #ifdef CONFIG_64BIT
2995 	return (__force __be32)siphash_4u64((u64)a, (u64)b, (u64)c, (u64)d, &exp_id_seed);
2996 #else
2997 	return (__force __be32)siphash_4u32((u32)a, (u32)b, (u32)c, (u32)d, &exp_id_seed);
2998 #endif
2999 }
3000 
3001 static int
ctnetlink_exp_dump_expect(struct sk_buff * skb,const struct nf_conntrack_expect * exp)3002 ctnetlink_exp_dump_expect(struct sk_buff *skb,
3003 			  const struct nf_conntrack_expect *exp)
3004 {
3005 	struct nf_conn *master = exp->master;
3006 	long timeout = ((long)exp->timeout.expires - (long)jiffies) / HZ;
3007 	struct nf_conn_help *help;
3008 #if IS_ENABLED(CONFIG_NF_NAT)
3009 	struct nlattr *nest_parms;
3010 	struct nf_conntrack_tuple nat_tuple = {};
3011 #endif
3012 	struct nf_ct_helper_expectfn *expfn;
3013 
3014 	if (timeout < 0)
3015 		timeout = 0;
3016 
3017 	if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
3018 		goto nla_put_failure;
3019 	if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
3020 		goto nla_put_failure;
3021 	if (ctnetlink_exp_dump_tuple(skb,
3022 				 &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
3023 				 CTA_EXPECT_MASTER) < 0)
3024 		goto nla_put_failure;
3025 
3026 #if IS_ENABLED(CONFIG_NF_NAT)
3027 	if (!nf_inet_addr_cmp(&exp->saved_addr, &any_addr) ||
3028 	    exp->saved_proto.all) {
3029 		nest_parms = nla_nest_start(skb, CTA_EXPECT_NAT);
3030 		if (!nest_parms)
3031 			goto nla_put_failure;
3032 
3033 		if (nla_put_be32(skb, CTA_EXPECT_NAT_DIR, htonl(exp->dir)))
3034 			goto nla_put_failure;
3035 
3036 		nat_tuple.src.l3num = nf_ct_l3num(master);
3037 		nat_tuple.src.u3 = exp->saved_addr;
3038 		nat_tuple.dst.protonum = nf_ct_protonum(master);
3039 		nat_tuple.src.u = exp->saved_proto;
3040 
3041 		if (ctnetlink_exp_dump_tuple(skb, &nat_tuple,
3042 						CTA_EXPECT_NAT_TUPLE) < 0)
3043 	                goto nla_put_failure;
3044 	        nla_nest_end(skb, nest_parms);
3045 	}
3046 #endif
3047 	if (nla_put_be32(skb, CTA_EXPECT_TIMEOUT, htonl(timeout)) ||
3048 	    nla_put_be32(skb, CTA_EXPECT_ID, nf_expect_get_id(exp)) ||
3049 	    nla_put_be32(skb, CTA_EXPECT_FLAGS, htonl(exp->flags)) ||
3050 	    nla_put_be32(skb, CTA_EXPECT_CLASS, htonl(exp->class)))
3051 		goto nla_put_failure;
3052 	help = nfct_help(master);
3053 	if (help) {
3054 		struct nf_conntrack_helper *helper;
3055 
3056 		helper = rcu_dereference(help->helper);
3057 		if (helper &&
3058 		    nla_put_string(skb, CTA_EXPECT_HELP_NAME, helper->name))
3059 			goto nla_put_failure;
3060 	}
3061 	expfn = nf_ct_helper_expectfn_find_by_symbol(exp->expectfn);
3062 	if (expfn != NULL &&
3063 	    nla_put_string(skb, CTA_EXPECT_FN, expfn->name))
3064 		goto nla_put_failure;
3065 
3066 	return 0;
3067 
3068 nla_put_failure:
3069 	return -1;
3070 }
3071 
3072 static int
ctnetlink_exp_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int event,const struct nf_conntrack_expect * exp)3073 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
3074 			int event, const struct nf_conntrack_expect *exp)
3075 {
3076 	struct nlmsghdr *nlh;
3077 	unsigned int flags = portid ? NLM_F_MULTI : 0;
3078 
3079 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK_EXP, event);
3080 	nlh = nfnl_msg_put(skb, portid, seq, event, flags,
3081 			   exp->tuple.src.l3num, NFNETLINK_V0, 0);
3082 	if (!nlh)
3083 		goto nlmsg_failure;
3084 
3085 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
3086 		goto nla_put_failure;
3087 
3088 	nlmsg_end(skb, nlh);
3089 	return skb->len;
3090 
3091 nlmsg_failure:
3092 nla_put_failure:
3093 	nlmsg_cancel(skb, nlh);
3094 	return -1;
3095 }
3096 
3097 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3098 static int
ctnetlink_expect_event(unsigned int events,const struct nf_exp_event * item)3099 ctnetlink_expect_event(unsigned int events, const struct nf_exp_event *item)
3100 {
3101 	struct nf_conntrack_expect *exp = item->exp;
3102 	struct net *net = nf_ct_exp_net(exp);
3103 	struct nlmsghdr *nlh;
3104 	struct sk_buff *skb;
3105 	unsigned int type, group;
3106 	int flags = 0;
3107 
3108 	if (events & (1 << IPEXP_DESTROY)) {
3109 		type = IPCTNL_MSG_EXP_DELETE;
3110 		group = NFNLGRP_CONNTRACK_EXP_DESTROY;
3111 	} else if (events & (1 << IPEXP_NEW)) {
3112 		type = IPCTNL_MSG_EXP_NEW;
3113 		flags = NLM_F_CREATE|NLM_F_EXCL;
3114 		group = NFNLGRP_CONNTRACK_EXP_NEW;
3115 	} else
3116 		return 0;
3117 
3118 	if (!item->report && !nfnetlink_has_listeners(net, group))
3119 		return 0;
3120 
3121 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
3122 	if (skb == NULL)
3123 		goto errout;
3124 
3125 	type = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK_EXP, type);
3126 	nlh = nfnl_msg_put(skb, item->portid, 0, type, flags,
3127 			   exp->tuple.src.l3num, NFNETLINK_V0, 0);
3128 	if (!nlh)
3129 		goto nlmsg_failure;
3130 
3131 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
3132 		goto nla_put_failure;
3133 
3134 	nlmsg_end(skb, nlh);
3135 	nfnetlink_send(skb, net, item->portid, group, item->report, GFP_ATOMIC);
3136 	return 0;
3137 
3138 nla_put_failure:
3139 	nlmsg_cancel(skb, nlh);
3140 nlmsg_failure:
3141 	kfree_skb(skb);
3142 errout:
3143 	nfnetlink_set_err(net, 0, 0, -ENOBUFS);
3144 	return 0;
3145 }
3146 #endif
ctnetlink_exp_done(struct netlink_callback * cb)3147 static int ctnetlink_exp_done(struct netlink_callback *cb)
3148 {
3149 	if (cb->args[1])
3150 		nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
3151 	return 0;
3152 }
3153 
3154 static int
ctnetlink_exp_dump_table(struct sk_buff * skb,struct netlink_callback * cb)3155 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
3156 {
3157 	struct net *net = sock_net(skb->sk);
3158 	struct nf_conntrack_expect *exp, *last;
3159 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
3160 	u_int8_t l3proto = nfmsg->nfgen_family;
3161 
3162 	rcu_read_lock();
3163 	last = (struct nf_conntrack_expect *)cb->args[1];
3164 	for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
3165 restart:
3166 		hlist_for_each_entry_rcu(exp, &nf_ct_expect_hash[cb->args[0]],
3167 					 hnode) {
3168 			if (l3proto && exp->tuple.src.l3num != l3proto)
3169 				continue;
3170 
3171 			if (!net_eq(nf_ct_net(exp->master), net))
3172 				continue;
3173 
3174 			if (cb->args[1]) {
3175 				if (exp != last)
3176 					continue;
3177 				cb->args[1] = 0;
3178 			}
3179 			if (ctnetlink_exp_fill_info(skb,
3180 						    NETLINK_CB(cb->skb).portid,
3181 						    cb->nlh->nlmsg_seq,
3182 						    IPCTNL_MSG_EXP_NEW,
3183 						    exp) < 0) {
3184 				if (!refcount_inc_not_zero(&exp->use))
3185 					continue;
3186 				cb->args[1] = (unsigned long)exp;
3187 				goto out;
3188 			}
3189 		}
3190 		if (cb->args[1]) {
3191 			cb->args[1] = 0;
3192 			goto restart;
3193 		}
3194 	}
3195 out:
3196 	rcu_read_unlock();
3197 	if (last)
3198 		nf_ct_expect_put(last);
3199 
3200 	return skb->len;
3201 }
3202 
3203 static int
ctnetlink_exp_ct_dump_table(struct sk_buff * skb,struct netlink_callback * cb)3204 ctnetlink_exp_ct_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
3205 {
3206 	struct nf_conntrack_expect *exp, *last;
3207 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
3208 	struct nf_conn *ct = cb->data;
3209 	struct nf_conn_help *help = nfct_help(ct);
3210 	u_int8_t l3proto = nfmsg->nfgen_family;
3211 
3212 	if (cb->args[0])
3213 		return 0;
3214 
3215 	rcu_read_lock();
3216 	last = (struct nf_conntrack_expect *)cb->args[1];
3217 restart:
3218 	hlist_for_each_entry_rcu(exp, &help->expectations, lnode) {
3219 		if (l3proto && exp->tuple.src.l3num != l3proto)
3220 			continue;
3221 		if (cb->args[1]) {
3222 			if (exp != last)
3223 				continue;
3224 			cb->args[1] = 0;
3225 		}
3226 		if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).portid,
3227 					    cb->nlh->nlmsg_seq,
3228 					    IPCTNL_MSG_EXP_NEW,
3229 					    exp) < 0) {
3230 			if (!refcount_inc_not_zero(&exp->use))
3231 				continue;
3232 			cb->args[1] = (unsigned long)exp;
3233 			goto out;
3234 		}
3235 	}
3236 	if (cb->args[1]) {
3237 		cb->args[1] = 0;
3238 		goto restart;
3239 	}
3240 	cb->args[0] = 1;
3241 out:
3242 	rcu_read_unlock();
3243 	if (last)
3244 		nf_ct_expect_put(last);
3245 
3246 	return skb->len;
3247 }
3248 
ctnetlink_dump_exp_ct(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)3249 static int ctnetlink_dump_exp_ct(struct net *net, struct sock *ctnl,
3250 				 struct sk_buff *skb,
3251 				 const struct nlmsghdr *nlh,
3252 				 const struct nlattr * const cda[],
3253 				 struct netlink_ext_ack *extack)
3254 {
3255 	int err;
3256 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3257 	u_int8_t u3 = nfmsg->nfgen_family;
3258 	struct nf_conntrack_tuple tuple;
3259 	struct nf_conntrack_tuple_hash *h;
3260 	struct nf_conn *ct;
3261 	struct nf_conntrack_zone zone;
3262 	struct netlink_dump_control c = {
3263 		.dump = ctnetlink_exp_ct_dump_table,
3264 		.done = ctnetlink_exp_done,
3265 	};
3266 
3267 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER,
3268 				    u3, NULL);
3269 	if (err < 0)
3270 		return err;
3271 
3272 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3273 	if (err < 0)
3274 		return err;
3275 
3276 	h = nf_conntrack_find_get(net, &zone, &tuple);
3277 	if (!h)
3278 		return -ENOENT;
3279 
3280 	ct = nf_ct_tuplehash_to_ctrack(h);
3281 	/* No expectation linked to this connection tracking. */
3282 	if (!nfct_help(ct)) {
3283 		nf_ct_put(ct);
3284 		return 0;
3285 	}
3286 
3287 	c.data = ct;
3288 
3289 	err = netlink_dump_start(ctnl, skb, nlh, &c);
3290 	nf_ct_put(ct);
3291 
3292 	return err;
3293 }
3294 
ctnetlink_get_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3295 static int ctnetlink_get_expect(struct sk_buff *skb,
3296 				const struct nfnl_info *info,
3297 				const struct nlattr * const cda[])
3298 {
3299 	u_int8_t u3 = info->nfmsg->nfgen_family;
3300 	struct nf_conntrack_tuple tuple;
3301 	struct nf_conntrack_expect *exp;
3302 	struct nf_conntrack_zone zone;
3303 	struct sk_buff *skb2;
3304 	int err;
3305 
3306 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
3307 		if (cda[CTA_EXPECT_MASTER])
3308 			return ctnetlink_dump_exp_ct(info->net, info->sk, skb,
3309 						     info->nlh, cda,
3310 						     info->extack);
3311 		else {
3312 			struct netlink_dump_control c = {
3313 				.dump = ctnetlink_exp_dump_table,
3314 				.done = ctnetlink_exp_done,
3315 			};
3316 			return netlink_dump_start(info->sk, skb, info->nlh, &c);
3317 		}
3318 	}
3319 
3320 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3321 	if (err < 0)
3322 		return err;
3323 
3324 	if (cda[CTA_EXPECT_TUPLE])
3325 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3326 					    u3, NULL);
3327 	else if (cda[CTA_EXPECT_MASTER])
3328 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER,
3329 					    u3, NULL);
3330 	else
3331 		return -EINVAL;
3332 
3333 	if (err < 0)
3334 		return err;
3335 
3336 	exp = nf_ct_expect_find_get(info->net, &zone, &tuple);
3337 	if (!exp)
3338 		return -ENOENT;
3339 
3340 	if (cda[CTA_EXPECT_ID]) {
3341 		__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
3342 
3343 		if (id != nf_expect_get_id(exp)) {
3344 			nf_ct_expect_put(exp);
3345 			return -ENOENT;
3346 		}
3347 	}
3348 
3349 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
3350 	if (!skb2) {
3351 		nf_ct_expect_put(exp);
3352 		return -ENOMEM;
3353 	}
3354 
3355 	rcu_read_lock();
3356 	err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).portid,
3357 				      info->nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
3358 				      exp);
3359 	rcu_read_unlock();
3360 	nf_ct_expect_put(exp);
3361 	if (err <= 0) {
3362 		kfree_skb(skb2);
3363 		return -ENOMEM;
3364 	}
3365 
3366 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
3367 }
3368 
expect_iter_name(struct nf_conntrack_expect * exp,void * data)3369 static bool expect_iter_name(struct nf_conntrack_expect *exp, void *data)
3370 {
3371 	struct nf_conntrack_helper *helper;
3372 	const struct nf_conn_help *m_help;
3373 	const char *name = data;
3374 
3375 	m_help = nfct_help(exp->master);
3376 
3377 	helper = rcu_dereference(m_help->helper);
3378 	if (!helper)
3379 		return false;
3380 
3381 	return strcmp(helper->name, name) == 0;
3382 }
3383 
expect_iter_all(struct nf_conntrack_expect * exp,void * data)3384 static bool expect_iter_all(struct nf_conntrack_expect *exp, void *data)
3385 {
3386 	return true;
3387 }
3388 
ctnetlink_del_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3389 static int ctnetlink_del_expect(struct sk_buff *skb,
3390 				const struct nfnl_info *info,
3391 				const struct nlattr * const cda[])
3392 {
3393 	u_int8_t u3 = info->nfmsg->nfgen_family;
3394 	struct nf_conntrack_expect *exp;
3395 	struct nf_conntrack_tuple tuple;
3396 	struct nf_conntrack_zone zone;
3397 	int err;
3398 
3399 	if (cda[CTA_EXPECT_TUPLE]) {
3400 		/* delete a single expect by tuple */
3401 		err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3402 		if (err < 0)
3403 			return err;
3404 
3405 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3406 					    u3, NULL);
3407 		if (err < 0)
3408 			return err;
3409 
3410 		/* bump usage count to 2 */
3411 		exp = nf_ct_expect_find_get(info->net, &zone, &tuple);
3412 		if (!exp)
3413 			return -ENOENT;
3414 
3415 		if (cda[CTA_EXPECT_ID]) {
3416 			__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
3417 
3418 			if (id != nf_expect_get_id(exp)) {
3419 				nf_ct_expect_put(exp);
3420 				return -ENOENT;
3421 			}
3422 		}
3423 
3424 		/* after list removal, usage count == 1 */
3425 		spin_lock_bh(&nf_conntrack_expect_lock);
3426 		if (del_timer(&exp->timeout)) {
3427 			nf_ct_unlink_expect_report(exp, NETLINK_CB(skb).portid,
3428 						   nlmsg_report(info->nlh));
3429 			nf_ct_expect_put(exp);
3430 		}
3431 		spin_unlock_bh(&nf_conntrack_expect_lock);
3432 		/* have to put what we 'get' above.
3433 		 * after this line usage count == 0 */
3434 		nf_ct_expect_put(exp);
3435 	} else if (cda[CTA_EXPECT_HELP_NAME]) {
3436 		char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
3437 
3438 		nf_ct_expect_iterate_net(info->net, expect_iter_name, name,
3439 					 NETLINK_CB(skb).portid,
3440 					 nlmsg_report(info->nlh));
3441 	} else {
3442 		/* This basically means we have to flush everything*/
3443 		nf_ct_expect_iterate_net(info->net, expect_iter_all, NULL,
3444 					 NETLINK_CB(skb).portid,
3445 					 nlmsg_report(info->nlh));
3446 	}
3447 
3448 	return 0;
3449 }
3450 static int
ctnetlink_change_expect(struct nf_conntrack_expect * x,const struct nlattr * const cda[])3451 ctnetlink_change_expect(struct nf_conntrack_expect *x,
3452 			const struct nlattr * const cda[])
3453 {
3454 	if (cda[CTA_EXPECT_TIMEOUT]) {
3455 		if (!del_timer(&x->timeout))
3456 			return -ETIME;
3457 
3458 		x->timeout.expires = jiffies +
3459 			ntohl(nla_get_be32(cda[CTA_EXPECT_TIMEOUT])) * HZ;
3460 		add_timer(&x->timeout);
3461 	}
3462 	return 0;
3463 }
3464 
3465 #if IS_ENABLED(CONFIG_NF_NAT)
3466 static const struct nla_policy exp_nat_nla_policy[CTA_EXPECT_NAT_MAX+1] = {
3467 	[CTA_EXPECT_NAT_DIR]	= { .type = NLA_U32 },
3468 	[CTA_EXPECT_NAT_TUPLE]	= { .type = NLA_NESTED },
3469 };
3470 #endif
3471 
3472 static int
ctnetlink_parse_expect_nat(const struct nlattr * attr,struct nf_conntrack_expect * exp,u_int8_t u3)3473 ctnetlink_parse_expect_nat(const struct nlattr *attr,
3474 			   struct nf_conntrack_expect *exp,
3475 			   u_int8_t u3)
3476 {
3477 #if IS_ENABLED(CONFIG_NF_NAT)
3478 	struct nlattr *tb[CTA_EXPECT_NAT_MAX+1];
3479 	struct nf_conntrack_tuple nat_tuple = {};
3480 	int err;
3481 
3482 	err = nla_parse_nested_deprecated(tb, CTA_EXPECT_NAT_MAX, attr,
3483 					  exp_nat_nla_policy, NULL);
3484 	if (err < 0)
3485 		return err;
3486 
3487 	if (!tb[CTA_EXPECT_NAT_DIR] || !tb[CTA_EXPECT_NAT_TUPLE])
3488 		return -EINVAL;
3489 
3490 	err = ctnetlink_parse_tuple((const struct nlattr * const *)tb,
3491 				    &nat_tuple, CTA_EXPECT_NAT_TUPLE,
3492 				    u3, NULL);
3493 	if (err < 0)
3494 		return err;
3495 
3496 	exp->saved_addr = nat_tuple.src.u3;
3497 	exp->saved_proto = nat_tuple.src.u;
3498 	exp->dir = ntohl(nla_get_be32(tb[CTA_EXPECT_NAT_DIR]));
3499 
3500 	return 0;
3501 #else
3502 	return -EOPNOTSUPP;
3503 #endif
3504 }
3505 
3506 static struct nf_conntrack_expect *
ctnetlink_alloc_expect(const struct nlattr * const cda[],struct nf_conn * ct,struct nf_conntrack_helper * helper,struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple * mask)3507 ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,
3508 		       struct nf_conntrack_helper *helper,
3509 		       struct nf_conntrack_tuple *tuple,
3510 		       struct nf_conntrack_tuple *mask)
3511 {
3512 	u_int32_t class = 0;
3513 	struct nf_conntrack_expect *exp;
3514 	struct nf_conn_help *help;
3515 	int err;
3516 
3517 	help = nfct_help(ct);
3518 	if (!help)
3519 		return ERR_PTR(-EOPNOTSUPP);
3520 
3521 	if (cda[CTA_EXPECT_CLASS] && helper) {
3522 		class = ntohl(nla_get_be32(cda[CTA_EXPECT_CLASS]));
3523 		if (class > helper->expect_class_max)
3524 			return ERR_PTR(-EINVAL);
3525 	}
3526 	exp = nf_ct_expect_alloc(ct);
3527 	if (!exp)
3528 		return ERR_PTR(-ENOMEM);
3529 
3530 	if (cda[CTA_EXPECT_FLAGS]) {
3531 		exp->flags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
3532 		exp->flags &= ~NF_CT_EXPECT_USERSPACE;
3533 	} else {
3534 		exp->flags = 0;
3535 	}
3536 	if (cda[CTA_EXPECT_FN]) {
3537 		const char *name = nla_data(cda[CTA_EXPECT_FN]);
3538 		struct nf_ct_helper_expectfn *expfn;
3539 
3540 		expfn = nf_ct_helper_expectfn_find_by_name(name);
3541 		if (expfn == NULL) {
3542 			err = -EINVAL;
3543 			goto err_out;
3544 		}
3545 		exp->expectfn = expfn->expectfn;
3546 	} else
3547 		exp->expectfn = NULL;
3548 
3549 	exp->class = class;
3550 	exp->master = ct;
3551 	exp->helper = helper;
3552 	exp->tuple = *tuple;
3553 	exp->mask.src.u3 = mask->src.u3;
3554 	exp->mask.src.u.all = mask->src.u.all;
3555 
3556 	if (cda[CTA_EXPECT_NAT]) {
3557 		err = ctnetlink_parse_expect_nat(cda[CTA_EXPECT_NAT],
3558 						 exp, nf_ct_l3num(ct));
3559 		if (err < 0)
3560 			goto err_out;
3561 	}
3562 	return exp;
3563 err_out:
3564 	nf_ct_expect_put(exp);
3565 	return ERR_PTR(err);
3566 }
3567 
3568 static int
ctnetlink_create_expect(struct net * net,const struct nf_conntrack_zone * zone,const struct nlattr * const cda[],u_int8_t u3,u32 portid,int report)3569 ctnetlink_create_expect(struct net *net,
3570 			const struct nf_conntrack_zone *zone,
3571 			const struct nlattr * const cda[],
3572 			u_int8_t u3, u32 portid, int report)
3573 {
3574 	struct nf_conntrack_tuple tuple, mask, master_tuple;
3575 	struct nf_conntrack_tuple_hash *h = NULL;
3576 	struct nf_conntrack_helper *helper = NULL;
3577 	struct nf_conntrack_expect *exp;
3578 	struct nf_conn *ct;
3579 	int err;
3580 
3581 	/* caller guarantees that those three CTA_EXPECT_* exist */
3582 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3583 				    u3, NULL);
3584 	if (err < 0)
3585 		return err;
3586 	err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK,
3587 				    u3, NULL);
3588 	if (err < 0)
3589 		return err;
3590 	err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER,
3591 				    u3, NULL);
3592 	if (err < 0)
3593 		return err;
3594 
3595 	/* Look for master conntrack of this expectation */
3596 	h = nf_conntrack_find_get(net, zone, &master_tuple);
3597 	if (!h)
3598 		return -ENOENT;
3599 	ct = nf_ct_tuplehash_to_ctrack(h);
3600 
3601 	rcu_read_lock();
3602 	if (cda[CTA_EXPECT_HELP_NAME]) {
3603 		const char *helpname = nla_data(cda[CTA_EXPECT_HELP_NAME]);
3604 
3605 		helper = __nf_conntrack_helper_find(helpname, u3,
3606 						    nf_ct_protonum(ct));
3607 		if (helper == NULL) {
3608 			rcu_read_unlock();
3609 #ifdef CONFIG_MODULES
3610 			if (request_module("nfct-helper-%s", helpname) < 0) {
3611 				err = -EOPNOTSUPP;
3612 				goto err_ct;
3613 			}
3614 			rcu_read_lock();
3615 			helper = __nf_conntrack_helper_find(helpname, u3,
3616 							    nf_ct_protonum(ct));
3617 			if (helper) {
3618 				err = -EAGAIN;
3619 				goto err_rcu;
3620 			}
3621 			rcu_read_unlock();
3622 #endif
3623 			err = -EOPNOTSUPP;
3624 			goto err_ct;
3625 		}
3626 	}
3627 
3628 	exp = ctnetlink_alloc_expect(cda, ct, helper, &tuple, &mask);
3629 	if (IS_ERR(exp)) {
3630 		err = PTR_ERR(exp);
3631 		goto err_rcu;
3632 	}
3633 
3634 	err = nf_ct_expect_related_report(exp, portid, report, 0);
3635 	nf_ct_expect_put(exp);
3636 err_rcu:
3637 	rcu_read_unlock();
3638 err_ct:
3639 	nf_ct_put(ct);
3640 	return err;
3641 }
3642 
ctnetlink_new_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3643 static int ctnetlink_new_expect(struct sk_buff *skb,
3644 				const struct nfnl_info *info,
3645 				const struct nlattr * const cda[])
3646 {
3647 	u_int8_t u3 = info->nfmsg->nfgen_family;
3648 	struct nf_conntrack_tuple tuple;
3649 	struct nf_conntrack_expect *exp;
3650 	struct nf_conntrack_zone zone;
3651 	int err;
3652 
3653 	if (!cda[CTA_EXPECT_TUPLE]
3654 	    || !cda[CTA_EXPECT_MASK]
3655 	    || !cda[CTA_EXPECT_MASTER])
3656 		return -EINVAL;
3657 
3658 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3659 	if (err < 0)
3660 		return err;
3661 
3662 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3663 				    u3, NULL);
3664 	if (err < 0)
3665 		return err;
3666 
3667 	spin_lock_bh(&nf_conntrack_expect_lock);
3668 	exp = __nf_ct_expect_find(info->net, &zone, &tuple);
3669 	if (!exp) {
3670 		spin_unlock_bh(&nf_conntrack_expect_lock);
3671 		err = -ENOENT;
3672 		if (info->nlh->nlmsg_flags & NLM_F_CREATE) {
3673 			err = ctnetlink_create_expect(info->net, &zone, cda, u3,
3674 						      NETLINK_CB(skb).portid,
3675 						      nlmsg_report(info->nlh));
3676 		}
3677 		return err;
3678 	}
3679 
3680 	err = -EEXIST;
3681 	if (!(info->nlh->nlmsg_flags & NLM_F_EXCL))
3682 		err = ctnetlink_change_expect(exp, cda);
3683 	spin_unlock_bh(&nf_conntrack_expect_lock);
3684 
3685 	return err;
3686 }
3687 
3688 static int
ctnetlink_exp_stat_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int cpu,const struct ip_conntrack_stat * st)3689 ctnetlink_exp_stat_fill_info(struct sk_buff *skb, u32 portid, u32 seq, int cpu,
3690 			     const struct ip_conntrack_stat *st)
3691 {
3692 	struct nlmsghdr *nlh;
3693 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
3694 
3695 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK,
3696 			      IPCTNL_MSG_EXP_GET_STATS_CPU);
3697 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
3698 			   NFNETLINK_V0, htons(cpu));
3699 	if (!nlh)
3700 		goto nlmsg_failure;
3701 
3702 	if (nla_put_be32(skb, CTA_STATS_EXP_NEW, htonl(st->expect_new)) ||
3703 	    nla_put_be32(skb, CTA_STATS_EXP_CREATE, htonl(st->expect_create)) ||
3704 	    nla_put_be32(skb, CTA_STATS_EXP_DELETE, htonl(st->expect_delete)))
3705 		goto nla_put_failure;
3706 
3707 	nlmsg_end(skb, nlh);
3708 	return skb->len;
3709 
3710 nla_put_failure:
3711 nlmsg_failure:
3712 	nlmsg_cancel(skb, nlh);
3713 	return -1;
3714 }
3715 
3716 static int
ctnetlink_exp_stat_cpu_dump(struct sk_buff * skb,struct netlink_callback * cb)3717 ctnetlink_exp_stat_cpu_dump(struct sk_buff *skb, struct netlink_callback *cb)
3718 {
3719 	int cpu;
3720 	struct net *net = sock_net(skb->sk);
3721 
3722 	if (cb->args[0] == nr_cpu_ids)
3723 		return 0;
3724 
3725 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
3726 		const struct ip_conntrack_stat *st;
3727 
3728 		if (!cpu_possible(cpu))
3729 			continue;
3730 
3731 		st = per_cpu_ptr(net->ct.stat, cpu);
3732 		if (ctnetlink_exp_stat_fill_info(skb, NETLINK_CB(cb->skb).portid,
3733 						 cb->nlh->nlmsg_seq,
3734 						 cpu, st) < 0)
3735 			break;
3736 	}
3737 	cb->args[0] = cpu;
3738 
3739 	return skb->len;
3740 }
3741 
ctnetlink_stat_exp_cpu(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3742 static int ctnetlink_stat_exp_cpu(struct sk_buff *skb,
3743 				  const struct nfnl_info *info,
3744 				  const struct nlattr * const cda[])
3745 {
3746 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
3747 		struct netlink_dump_control c = {
3748 			.dump = ctnetlink_exp_stat_cpu_dump,
3749 		};
3750 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
3751 	}
3752 
3753 	return 0;
3754 }
3755 
3756 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3757 static struct nf_ct_event_notifier ctnl_notifier = {
3758 	.ct_event = ctnetlink_conntrack_event,
3759 	.exp_event = ctnetlink_expect_event,
3760 };
3761 #endif
3762 
3763 static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
3764 	[IPCTNL_MSG_CT_NEW]	= {
3765 		.call		= ctnetlink_new_conntrack,
3766 		.type		= NFNL_CB_MUTEX,
3767 		.attr_count	= CTA_MAX,
3768 		.policy		= ct_nla_policy
3769 	},
3770 	[IPCTNL_MSG_CT_GET]	= {
3771 		.call		= ctnetlink_get_conntrack,
3772 		.type		= NFNL_CB_MUTEX,
3773 		.attr_count	= CTA_MAX,
3774 		.policy		= ct_nla_policy
3775 	},
3776 	[IPCTNL_MSG_CT_DELETE]	= {
3777 		.call		= ctnetlink_del_conntrack,
3778 		.type		= NFNL_CB_MUTEX,
3779 		.attr_count	= CTA_MAX,
3780 		.policy		= ct_nla_policy
3781 	},
3782 	[IPCTNL_MSG_CT_GET_CTRZERO] = {
3783 		.call		= ctnetlink_get_conntrack,
3784 		.type		= NFNL_CB_MUTEX,
3785 		.attr_count	= CTA_MAX,
3786 		.policy		= ct_nla_policy
3787 	},
3788 	[IPCTNL_MSG_CT_GET_STATS_CPU] = {
3789 		.call		= ctnetlink_stat_ct_cpu,
3790 		.type		= NFNL_CB_MUTEX,
3791 	},
3792 	[IPCTNL_MSG_CT_GET_STATS] = {
3793 		.call		= ctnetlink_stat_ct,
3794 		.type		= NFNL_CB_MUTEX,
3795 	},
3796 	[IPCTNL_MSG_CT_GET_DYING] = {
3797 		.call		= ctnetlink_get_ct_dying,
3798 		.type		= NFNL_CB_MUTEX,
3799 	},
3800 	[IPCTNL_MSG_CT_GET_UNCONFIRMED]	= {
3801 		.call		= ctnetlink_get_ct_unconfirmed,
3802 		.type		= NFNL_CB_MUTEX,
3803 	},
3804 };
3805 
3806 static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
3807 	[IPCTNL_MSG_EXP_GET] = {
3808 		.call		= ctnetlink_get_expect,
3809 		.type		= NFNL_CB_MUTEX,
3810 		.attr_count	= CTA_EXPECT_MAX,
3811 		.policy		= exp_nla_policy
3812 	},
3813 	[IPCTNL_MSG_EXP_NEW] = {
3814 		.call		= ctnetlink_new_expect,
3815 		.type		= NFNL_CB_MUTEX,
3816 		.attr_count	= CTA_EXPECT_MAX,
3817 		.policy		= exp_nla_policy
3818 	},
3819 	[IPCTNL_MSG_EXP_DELETE] = {
3820 		.call		= ctnetlink_del_expect,
3821 		.type		= NFNL_CB_MUTEX,
3822 		.attr_count	= CTA_EXPECT_MAX,
3823 		.policy		= exp_nla_policy
3824 	},
3825 	[IPCTNL_MSG_EXP_GET_STATS_CPU] = {
3826 		.call		= ctnetlink_stat_exp_cpu,
3827 		.type		= NFNL_CB_MUTEX,
3828 	},
3829 };
3830 
3831 static const struct nfnetlink_subsystem ctnl_subsys = {
3832 	.name				= "conntrack",
3833 	.subsys_id			= NFNL_SUBSYS_CTNETLINK,
3834 	.cb_count			= IPCTNL_MSG_MAX,
3835 	.cb				= ctnl_cb,
3836 };
3837 
3838 static const struct nfnetlink_subsystem ctnl_exp_subsys = {
3839 	.name				= "conntrack_expect",
3840 	.subsys_id			= NFNL_SUBSYS_CTNETLINK_EXP,
3841 	.cb_count			= IPCTNL_MSG_EXP_MAX,
3842 	.cb				= ctnl_exp_cb,
3843 };
3844 
3845 MODULE_ALIAS("ip_conntrack_netlink");
3846 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
3847 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
3848 
ctnetlink_net_init(struct net * net)3849 static int __net_init ctnetlink_net_init(struct net *net)
3850 {
3851 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3852 	nf_conntrack_register_notifier(net, &ctnl_notifier);
3853 #endif
3854 	return 0;
3855 }
3856 
ctnetlink_net_pre_exit(struct net * net)3857 static void ctnetlink_net_pre_exit(struct net *net)
3858 {
3859 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3860 	nf_conntrack_unregister_notifier(net);
3861 #endif
3862 }
3863 
3864 static struct pernet_operations ctnetlink_net_ops = {
3865 	.init		= ctnetlink_net_init,
3866 	.pre_exit	= ctnetlink_net_pre_exit,
3867 };
3868 
ctnetlink_init(void)3869 static int __init ctnetlink_init(void)
3870 {
3871 	int ret;
3872 
3873 	NL_ASSERT_DUMP_CTX_FITS(struct ctnetlink_list_dump_ctx);
3874 
3875 	ret = nfnetlink_subsys_register(&ctnl_subsys);
3876 	if (ret < 0) {
3877 		pr_err("ctnetlink_init: cannot register with nfnetlink.\n");
3878 		goto err_out;
3879 	}
3880 
3881 	ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
3882 	if (ret < 0) {
3883 		pr_err("ctnetlink_init: cannot register exp with nfnetlink.\n");
3884 		goto err_unreg_subsys;
3885 	}
3886 
3887 	ret = register_pernet_subsys(&ctnetlink_net_ops);
3888 	if (ret < 0) {
3889 		pr_err("ctnetlink_init: cannot register pernet operations\n");
3890 		goto err_unreg_exp_subsys;
3891 	}
3892 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
3893 	/* setup interaction between nf_queue and nf_conntrack_netlink. */
3894 	RCU_INIT_POINTER(nfnl_ct_hook, &ctnetlink_glue_hook);
3895 #endif
3896 	return 0;
3897 
3898 err_unreg_exp_subsys:
3899 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
3900 err_unreg_subsys:
3901 	nfnetlink_subsys_unregister(&ctnl_subsys);
3902 err_out:
3903 	return ret;
3904 }
3905 
ctnetlink_exit(void)3906 static void __exit ctnetlink_exit(void)
3907 {
3908 	unregister_pernet_subsys(&ctnetlink_net_ops);
3909 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
3910 	nfnetlink_subsys_unregister(&ctnl_subsys);
3911 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
3912 	RCU_INIT_POINTER(nfnl_ct_hook, NULL);
3913 #endif
3914 	synchronize_rcu();
3915 }
3916 
3917 module_init(ctnetlink_init);
3918 module_exit(ctnetlink_exit);
3919