• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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 
ctnetlink_dump_tuples_proto(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_l4proto * l4proto)61 static int ctnetlink_dump_tuples_proto(struct sk_buff *skb,
62 				const struct nf_conntrack_tuple *tuple,
63 				const struct nf_conntrack_l4proto *l4proto)
64 {
65 	int ret = 0;
66 	struct nlattr *nest_parms;
67 
68 	nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO);
69 	if (!nest_parms)
70 		goto nla_put_failure;
71 	if (nla_put_u8(skb, CTA_PROTO_NUM, tuple->dst.protonum))
72 		goto nla_put_failure;
73 
74 	if (likely(l4proto->tuple_to_nlattr))
75 		ret = l4proto->tuple_to_nlattr(skb, tuple);
76 
77 	nla_nest_end(skb, nest_parms);
78 
79 	return ret;
80 
81 nla_put_failure:
82 	return -1;
83 }
84 
ipv4_tuple_to_nlattr(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)85 static int ipv4_tuple_to_nlattr(struct sk_buff *skb,
86 				const struct nf_conntrack_tuple *tuple)
87 {
88 	if (nla_put_in_addr(skb, CTA_IP_V4_SRC, tuple->src.u3.ip) ||
89 	    nla_put_in_addr(skb, CTA_IP_V4_DST, tuple->dst.u3.ip))
90 		return -EMSGSIZE;
91 	return 0;
92 }
93 
ipv6_tuple_to_nlattr(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)94 static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
95 				const struct nf_conntrack_tuple *tuple)
96 {
97 	if (nla_put_in6_addr(skb, CTA_IP_V6_SRC, &tuple->src.u3.in6) ||
98 	    nla_put_in6_addr(skb, CTA_IP_V6_DST, &tuple->dst.u3.in6))
99 		return -EMSGSIZE;
100 	return 0;
101 }
102 
ctnetlink_dump_tuples_ip(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)103 static int ctnetlink_dump_tuples_ip(struct sk_buff *skb,
104 				    const struct nf_conntrack_tuple *tuple)
105 {
106 	int ret = 0;
107 	struct nlattr *nest_parms;
108 
109 	nest_parms = nla_nest_start(skb, CTA_TUPLE_IP);
110 	if (!nest_parms)
111 		goto nla_put_failure;
112 
113 	switch (tuple->src.l3num) {
114 	case NFPROTO_IPV4:
115 		ret = ipv4_tuple_to_nlattr(skb, tuple);
116 		break;
117 	case NFPROTO_IPV6:
118 		ret = ipv6_tuple_to_nlattr(skb, tuple);
119 		break;
120 	}
121 
122 	nla_nest_end(skb, nest_parms);
123 
124 	return ret;
125 
126 nla_put_failure:
127 	return -1;
128 }
129 
ctnetlink_dump_tuples(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)130 static int ctnetlink_dump_tuples(struct sk_buff *skb,
131 				 const struct nf_conntrack_tuple *tuple)
132 {
133 	const struct nf_conntrack_l4proto *l4proto;
134 	int ret;
135 
136 	rcu_read_lock();
137 	ret = ctnetlink_dump_tuples_ip(skb, tuple);
138 
139 	if (ret >= 0) {
140 		l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
141 		ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
142 	}
143 	rcu_read_unlock();
144 	return ret;
145 }
146 
ctnetlink_dump_zone_id(struct sk_buff * skb,int attrtype,const struct nf_conntrack_zone * zone,int dir)147 static int ctnetlink_dump_zone_id(struct sk_buff *skb, int attrtype,
148 				  const struct nf_conntrack_zone *zone, int dir)
149 {
150 	if (zone->id == NF_CT_DEFAULT_ZONE_ID || zone->dir != dir)
151 		return 0;
152 	if (nla_put_be16(skb, attrtype, htons(zone->id)))
153 		goto nla_put_failure;
154 	return 0;
155 
156 nla_put_failure:
157 	return -1;
158 }
159 
ctnetlink_dump_status(struct sk_buff * skb,const struct nf_conn * ct)160 static int ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
161 {
162 	if (nla_put_be32(skb, CTA_STATUS, htonl(ct->status)))
163 		goto nla_put_failure;
164 	return 0;
165 
166 nla_put_failure:
167 	return -1;
168 }
169 
ctnetlink_dump_timeout(struct sk_buff * skb,const struct nf_conn * ct,bool skip_zero)170 static int ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct,
171 				  bool skip_zero)
172 {
173 	long timeout = nf_ct_expires(ct) / HZ;
174 
175 	if (skip_zero && timeout == 0)
176 		return 0;
177 
178 	if (nla_put_be32(skb, CTA_TIMEOUT, htonl(timeout)))
179 		goto nla_put_failure;
180 	return 0;
181 
182 nla_put_failure:
183 	return -1;
184 }
185 
ctnetlink_dump_protoinfo(struct sk_buff * skb,struct nf_conn * ct,bool destroy)186 static int ctnetlink_dump_protoinfo(struct sk_buff *skb, struct nf_conn *ct,
187 				    bool destroy)
188 {
189 	const struct nf_conntrack_l4proto *l4proto;
190 	struct nlattr *nest_proto;
191 	int ret;
192 
193 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
194 	if (!l4proto->to_nlattr)
195 		return 0;
196 
197 	nest_proto = nla_nest_start(skb, CTA_PROTOINFO);
198 	if (!nest_proto)
199 		goto nla_put_failure;
200 
201 	ret = l4proto->to_nlattr(skb, nest_proto, ct, destroy);
202 
203 	nla_nest_end(skb, nest_proto);
204 
205 	return ret;
206 
207 nla_put_failure:
208 	return -1;
209 }
210 
ctnetlink_dump_helpinfo(struct sk_buff * skb,const struct nf_conn * ct)211 static int ctnetlink_dump_helpinfo(struct sk_buff *skb,
212 				   const struct nf_conn *ct)
213 {
214 	struct nlattr *nest_helper;
215 	const struct nf_conn_help *help = nfct_help(ct);
216 	struct nf_conntrack_helper *helper;
217 
218 	if (!help)
219 		return 0;
220 
221 	rcu_read_lock();
222 	helper = rcu_dereference(help->helper);
223 	if (!helper)
224 		goto out;
225 
226 	nest_helper = nla_nest_start(skb, CTA_HELP);
227 	if (!nest_helper)
228 		goto nla_put_failure;
229 	if (nla_put_string(skb, CTA_HELP_NAME, helper->name))
230 		goto nla_put_failure;
231 
232 	if (helper->to_nlattr)
233 		helper->to_nlattr(skb, ct);
234 
235 	nla_nest_end(skb, nest_helper);
236 out:
237 	rcu_read_unlock();
238 	return 0;
239 
240 nla_put_failure:
241 	rcu_read_unlock();
242 	return -1;
243 }
244 
245 static int
dump_counters(struct sk_buff * skb,struct nf_conn_acct * acct,enum ip_conntrack_dir dir,int type)246 dump_counters(struct sk_buff *skb, struct nf_conn_acct *acct,
247 	      enum ip_conntrack_dir dir, int type)
248 {
249 	enum ctattr_type attr = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
250 	struct nf_conn_counter *counter = acct->counter;
251 	struct nlattr *nest_count;
252 	u64 pkts, bytes;
253 
254 	if (type == IPCTNL_MSG_CT_GET_CTRZERO) {
255 		pkts = atomic64_xchg(&counter[dir].packets, 0);
256 		bytes = atomic64_xchg(&counter[dir].bytes, 0);
257 	} else {
258 		pkts = atomic64_read(&counter[dir].packets);
259 		bytes = atomic64_read(&counter[dir].bytes);
260 	}
261 
262 	nest_count = nla_nest_start(skb, attr);
263 	if (!nest_count)
264 		goto nla_put_failure;
265 
266 	if (nla_put_be64(skb, CTA_COUNTERS_PACKETS, cpu_to_be64(pkts),
267 			 CTA_COUNTERS_PAD) ||
268 	    nla_put_be64(skb, CTA_COUNTERS_BYTES, cpu_to_be64(bytes),
269 			 CTA_COUNTERS_PAD))
270 		goto nla_put_failure;
271 
272 	nla_nest_end(skb, nest_count);
273 
274 	return 0;
275 
276 nla_put_failure:
277 	return -1;
278 }
279 
280 static int
ctnetlink_dump_acct(struct sk_buff * skb,const struct nf_conn * ct,int type)281 ctnetlink_dump_acct(struct sk_buff *skb, const struct nf_conn *ct, int type)
282 {
283 	struct nf_conn_acct *acct = nf_conn_acct_find(ct);
284 
285 	if (!acct)
286 		return 0;
287 
288 	if (dump_counters(skb, acct, IP_CT_DIR_ORIGINAL, type) < 0)
289 		return -1;
290 	if (dump_counters(skb, acct, IP_CT_DIR_REPLY, type) < 0)
291 		return -1;
292 
293 	return 0;
294 }
295 
296 static int
ctnetlink_dump_timestamp(struct sk_buff * skb,const struct nf_conn * ct)297 ctnetlink_dump_timestamp(struct sk_buff *skb, const struct nf_conn *ct)
298 {
299 	struct nlattr *nest_count;
300 	const struct nf_conn_tstamp *tstamp;
301 
302 	tstamp = nf_conn_tstamp_find(ct);
303 	if (!tstamp)
304 		return 0;
305 
306 	nest_count = nla_nest_start(skb, CTA_TIMESTAMP);
307 	if (!nest_count)
308 		goto nla_put_failure;
309 
310 	if (nla_put_be64(skb, CTA_TIMESTAMP_START, cpu_to_be64(tstamp->start),
311 			 CTA_TIMESTAMP_PAD) ||
312 	    (tstamp->stop != 0 && nla_put_be64(skb, CTA_TIMESTAMP_STOP,
313 					       cpu_to_be64(tstamp->stop),
314 					       CTA_TIMESTAMP_PAD)))
315 		goto nla_put_failure;
316 	nla_nest_end(skb, nest_count);
317 
318 	return 0;
319 
320 nla_put_failure:
321 	return -1;
322 }
323 
324 #ifdef CONFIG_NF_CONNTRACK_MARK
ctnetlink_dump_mark(struct sk_buff * skb,const struct nf_conn * ct,bool dump)325 static int ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct,
326 			       bool dump)
327 {
328 	u32 mark = READ_ONCE(ct->mark);
329 
330 	if (!mark && !dump)
331 		return 0;
332 
333 	if (nla_put_be32(skb, CTA_MARK, htonl(mark)))
334 		goto nla_put_failure;
335 	return 0;
336 
337 nla_put_failure:
338 	return -1;
339 }
340 #else
341 #define ctnetlink_dump_mark(a, b, c) (0)
342 #endif
343 
344 #ifdef CONFIG_NF_CONNTRACK_SECMARK
ctnetlink_dump_secctx(struct sk_buff * skb,const struct nf_conn * ct)345 static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
346 {
347 	struct nlattr *nest_secctx;
348 	int len, ret;
349 	char *secctx;
350 
351 	ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
352 	if (ret)
353 		return 0;
354 
355 	ret = -1;
356 	nest_secctx = nla_nest_start(skb, CTA_SECCTX);
357 	if (!nest_secctx)
358 		goto nla_put_failure;
359 
360 	if (nla_put_string(skb, CTA_SECCTX_NAME, secctx))
361 		goto nla_put_failure;
362 	nla_nest_end(skb, nest_secctx);
363 
364 	ret = 0;
365 nla_put_failure:
366 	security_release_secctx(secctx, len);
367 	return ret;
368 }
369 #else
370 #define ctnetlink_dump_secctx(a, b) (0)
371 #endif
372 
373 #ifdef CONFIG_NF_CONNTRACK_LABELS
ctnetlink_label_size(const struct nf_conn * ct)374 static inline int ctnetlink_label_size(const struct nf_conn *ct)
375 {
376 	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
377 
378 	if (!labels)
379 		return 0;
380 	return nla_total_size(sizeof(labels->bits));
381 }
382 
383 static int
ctnetlink_dump_labels(struct sk_buff * skb,const struct nf_conn * ct)384 ctnetlink_dump_labels(struct sk_buff *skb, const struct nf_conn *ct)
385 {
386 	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
387 	unsigned int i;
388 
389 	if (!labels)
390 		return 0;
391 
392 	i = 0;
393 	do {
394 		if (labels->bits[i] != 0)
395 			return nla_put(skb, CTA_LABELS, sizeof(labels->bits),
396 				       labels->bits);
397 		i++;
398 	} while (i < ARRAY_SIZE(labels->bits));
399 
400 	return 0;
401 }
402 #else
403 #define ctnetlink_dump_labels(a, b) (0)
404 #define ctnetlink_label_size(a)	(0)
405 #endif
406 
407 #define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
408 
ctnetlink_dump_master(struct sk_buff * skb,const struct nf_conn * ct)409 static int ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
410 {
411 	struct nlattr *nest_parms;
412 
413 	if (!(ct->status & IPS_EXPECTED))
414 		return 0;
415 
416 	nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER);
417 	if (!nest_parms)
418 		goto nla_put_failure;
419 	if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
420 		goto nla_put_failure;
421 	nla_nest_end(skb, nest_parms);
422 
423 	return 0;
424 
425 nla_put_failure:
426 	return -1;
427 }
428 
429 static int
dump_ct_seq_adj(struct sk_buff * skb,const struct nf_ct_seqadj * seq,int type)430 dump_ct_seq_adj(struct sk_buff *skb, const struct nf_ct_seqadj *seq, int type)
431 {
432 	struct nlattr *nest_parms;
433 
434 	nest_parms = nla_nest_start(skb, type);
435 	if (!nest_parms)
436 		goto nla_put_failure;
437 
438 	if (nla_put_be32(skb, CTA_SEQADJ_CORRECTION_POS,
439 			 htonl(seq->correction_pos)) ||
440 	    nla_put_be32(skb, CTA_SEQADJ_OFFSET_BEFORE,
441 			 htonl(seq->offset_before)) ||
442 	    nla_put_be32(skb, CTA_SEQADJ_OFFSET_AFTER,
443 			 htonl(seq->offset_after)))
444 		goto nla_put_failure;
445 
446 	nla_nest_end(skb, nest_parms);
447 
448 	return 0;
449 
450 nla_put_failure:
451 	return -1;
452 }
453 
ctnetlink_dump_ct_seq_adj(struct sk_buff * skb,struct nf_conn * ct)454 static int ctnetlink_dump_ct_seq_adj(struct sk_buff *skb, struct nf_conn *ct)
455 {
456 	struct nf_conn_seqadj *seqadj = nfct_seqadj(ct);
457 	struct nf_ct_seqadj *seq;
458 
459 	if (!(ct->status & IPS_SEQ_ADJUST) || !seqadj)
460 		return 0;
461 
462 	spin_lock_bh(&ct->lock);
463 	seq = &seqadj->seq[IP_CT_DIR_ORIGINAL];
464 	if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_ORIG) == -1)
465 		goto err;
466 
467 	seq = &seqadj->seq[IP_CT_DIR_REPLY];
468 	if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_REPLY) == -1)
469 		goto err;
470 
471 	spin_unlock_bh(&ct->lock);
472 	return 0;
473 err:
474 	spin_unlock_bh(&ct->lock);
475 	return -1;
476 }
477 
ctnetlink_dump_ct_synproxy(struct sk_buff * skb,struct nf_conn * ct)478 static int ctnetlink_dump_ct_synproxy(struct sk_buff *skb, struct nf_conn *ct)
479 {
480 	struct nf_conn_synproxy *synproxy = nfct_synproxy(ct);
481 	struct nlattr *nest_parms;
482 
483 	if (!synproxy)
484 		return 0;
485 
486 	nest_parms = nla_nest_start(skb, CTA_SYNPROXY);
487 	if (!nest_parms)
488 		goto nla_put_failure;
489 
490 	if (nla_put_be32(skb, CTA_SYNPROXY_ISN, htonl(synproxy->isn)) ||
491 	    nla_put_be32(skb, CTA_SYNPROXY_ITS, htonl(synproxy->its)) ||
492 	    nla_put_be32(skb, CTA_SYNPROXY_TSOFF, htonl(synproxy->tsoff)))
493 		goto nla_put_failure;
494 
495 	nla_nest_end(skb, nest_parms);
496 
497 	return 0;
498 
499 nla_put_failure:
500 	return -1;
501 }
502 
ctnetlink_dump_id(struct sk_buff * skb,const struct nf_conn * ct)503 static int ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
504 {
505 	__be32 id = (__force __be32)nf_ct_get_id(ct);
506 
507 	if (nla_put_be32(skb, CTA_ID, id))
508 		goto nla_put_failure;
509 	return 0;
510 
511 nla_put_failure:
512 	return -1;
513 }
514 
ctnetlink_dump_use(struct sk_buff * skb,const struct nf_conn * ct)515 static int ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
516 {
517 	if (nla_put_be32(skb, CTA_USE, htonl(refcount_read(&ct->ct_general.use))))
518 		goto nla_put_failure;
519 	return 0;
520 
521 nla_put_failure:
522 	return -1;
523 }
524 
525 /* all these functions access ct->ext. Caller must either hold a reference
526  * on ct or prevent its deletion by holding either the bucket spinlock or
527  * pcpu dying list lock.
528  */
ctnetlink_dump_extinfo(struct sk_buff * skb,struct nf_conn * ct,u32 type)529 static int ctnetlink_dump_extinfo(struct sk_buff *skb,
530 				  struct nf_conn *ct, u32 type)
531 {
532 	if (ctnetlink_dump_acct(skb, ct, type) < 0 ||
533 	    ctnetlink_dump_timestamp(skb, ct) < 0 ||
534 	    ctnetlink_dump_helpinfo(skb, ct) < 0 ||
535 	    ctnetlink_dump_labels(skb, ct) < 0 ||
536 	    ctnetlink_dump_ct_seq_adj(skb, ct) < 0 ||
537 	    ctnetlink_dump_ct_synproxy(skb, ct) < 0)
538 		return -1;
539 
540 	return 0;
541 }
542 
ctnetlink_dump_info(struct sk_buff * skb,struct nf_conn * ct)543 static int ctnetlink_dump_info(struct sk_buff *skb, struct nf_conn *ct)
544 {
545 	if (ctnetlink_dump_status(skb, ct) < 0 ||
546 	    ctnetlink_dump_mark(skb, ct, true) < 0 ||
547 	    ctnetlink_dump_secctx(skb, ct) < 0 ||
548 	    ctnetlink_dump_id(skb, ct) < 0 ||
549 	    ctnetlink_dump_use(skb, ct) < 0 ||
550 	    ctnetlink_dump_master(skb, ct) < 0)
551 		return -1;
552 
553 	if (!test_bit(IPS_OFFLOAD_BIT, &ct->status) &&
554 	    (ctnetlink_dump_timeout(skb, ct, false) < 0 ||
555 	     ctnetlink_dump_protoinfo(skb, ct, false) < 0))
556 		return -1;
557 
558 	return 0;
559 }
560 
561 static int
ctnetlink_fill_info(struct sk_buff * skb,u32 portid,u32 seq,u32 type,struct nf_conn * ct,bool extinfo,unsigned int flags)562 ctnetlink_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
563 		    struct nf_conn *ct, bool extinfo, unsigned int flags)
564 {
565 	const struct nf_conntrack_zone *zone;
566 	struct nlmsghdr *nlh;
567 	struct nlattr *nest_parms;
568 	unsigned int event;
569 
570 	if (portid)
571 		flags |= NLM_F_MULTI;
572 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_NEW);
573 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, nf_ct_l3num(ct),
574 			   NFNETLINK_V0, 0);
575 	if (!nlh)
576 		goto nlmsg_failure;
577 
578 	zone = nf_ct_zone(ct);
579 
580 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
581 	if (!nest_parms)
582 		goto nla_put_failure;
583 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
584 		goto nla_put_failure;
585 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
586 				   NF_CT_ZONE_DIR_ORIG) < 0)
587 		goto nla_put_failure;
588 	nla_nest_end(skb, nest_parms);
589 
590 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
591 	if (!nest_parms)
592 		goto nla_put_failure;
593 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
594 		goto nla_put_failure;
595 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
596 				   NF_CT_ZONE_DIR_REPL) < 0)
597 		goto nla_put_failure;
598 	nla_nest_end(skb, nest_parms);
599 
600 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
601 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
602 		goto nla_put_failure;
603 
604 	if (ctnetlink_dump_info(skb, ct) < 0)
605 		goto nla_put_failure;
606 	if (extinfo && ctnetlink_dump_extinfo(skb, ct, type) < 0)
607 		goto nla_put_failure;
608 
609 	nlmsg_end(skb, nlh);
610 	return skb->len;
611 
612 nlmsg_failure:
613 nla_put_failure:
614 	nlmsg_cancel(skb, nlh);
615 	return -1;
616 }
617 
618 static const struct nla_policy cta_ip_nla_policy[CTA_IP_MAX + 1] = {
619 	[CTA_IP_V4_SRC]	= { .type = NLA_U32 },
620 	[CTA_IP_V4_DST]	= { .type = NLA_U32 },
621 	[CTA_IP_V6_SRC]	= { .len = sizeof(__be32) * 4 },
622 	[CTA_IP_V6_DST]	= { .len = sizeof(__be32) * 4 },
623 };
624 
625 #if defined(CONFIG_NETFILTER_NETLINK_GLUE_CT) || defined(CONFIG_NF_CONNTRACK_EVENTS)
ctnetlink_proto_size(const struct nf_conn * ct)626 static size_t ctnetlink_proto_size(const struct nf_conn *ct)
627 {
628 	const struct nf_conntrack_l4proto *l4proto;
629 	size_t len, len4 = 0;
630 
631 	len = nla_policy_len(cta_ip_nla_policy, CTA_IP_MAX + 1);
632 	len *= 3u; /* ORIG, REPLY, MASTER */
633 
634 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
635 	len += l4proto->nlattr_size;
636 	if (l4proto->nlattr_tuple_size) {
637 		len4 = l4proto->nlattr_tuple_size();
638 		len4 *= 3u; /* ORIG, REPLY, MASTER */
639 	}
640 
641 	return len + len4;
642 }
643 #endif
644 
ctnetlink_acct_size(const struct nf_conn * ct)645 static inline size_t ctnetlink_acct_size(const struct nf_conn *ct)
646 {
647 	if (!nf_ct_ext_exist(ct, NF_CT_EXT_ACCT))
648 		return 0;
649 	return 2 * nla_total_size(0) /* CTA_COUNTERS_ORIG|REPL */
650 	       + 2 * nla_total_size_64bit(sizeof(uint64_t)) /* CTA_COUNTERS_PACKETS */
651 	       + 2 * nla_total_size_64bit(sizeof(uint64_t)) /* CTA_COUNTERS_BYTES */
652 	       ;
653 }
654 
ctnetlink_secctx_size(const struct nf_conn * ct)655 static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
656 {
657 #ifdef CONFIG_NF_CONNTRACK_SECMARK
658 	int len, ret;
659 
660 	ret = security_secid_to_secctx(ct->secmark, NULL, &len);
661 	if (ret)
662 		return 0;
663 
664 	return nla_total_size(0) /* CTA_SECCTX */
665 	       + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
666 #else
667 	return 0;
668 #endif
669 }
670 
ctnetlink_timestamp_size(const struct nf_conn * ct)671 static inline size_t ctnetlink_timestamp_size(const struct nf_conn *ct)
672 {
673 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
674 	if (!nf_ct_ext_exist(ct, NF_CT_EXT_TSTAMP))
675 		return 0;
676 	return nla_total_size(0) + 2 * nla_total_size_64bit(sizeof(uint64_t));
677 #else
678 	return 0;
679 #endif
680 }
681 
682 #ifdef CONFIG_NF_CONNTRACK_EVENTS
ctnetlink_nlmsg_size(const struct nf_conn * ct)683 static size_t ctnetlink_nlmsg_size(const struct nf_conn *ct)
684 {
685 	return NLMSG_ALIGN(sizeof(struct nfgenmsg))
686 	       + 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
687 	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
688 	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
689 	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
690 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
691 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
692 	       + ctnetlink_acct_size(ct)
693 	       + ctnetlink_timestamp_size(ct)
694 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
695 	       + nla_total_size(0) /* CTA_PROTOINFO */
696 	       + nla_total_size(0) /* CTA_HELP */
697 	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
698 	       + ctnetlink_secctx_size(ct)
699 #if IS_ENABLED(CONFIG_NF_NAT)
700 	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
701 	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
702 #endif
703 #ifdef CONFIG_NF_CONNTRACK_MARK
704 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
705 #endif
706 #ifdef CONFIG_NF_CONNTRACK_ZONES
707 	       + nla_total_size(sizeof(u_int16_t)) /* CTA_ZONE|CTA_TUPLE_ZONE */
708 #endif
709 	       + ctnetlink_proto_size(ct)
710 	       + ctnetlink_label_size(ct)
711 	       ;
712 }
713 
714 static int
ctnetlink_conntrack_event(unsigned int events,const struct nf_ct_event * item)715 ctnetlink_conntrack_event(unsigned int events, const struct nf_ct_event *item)
716 {
717 	const struct nf_conntrack_zone *zone;
718 	struct net *net;
719 	struct nlmsghdr *nlh;
720 	struct nlattr *nest_parms;
721 	struct nf_conn *ct = item->ct;
722 	struct sk_buff *skb;
723 	unsigned int type;
724 	unsigned int flags = 0, group;
725 	int err;
726 
727 	if (events & (1 << IPCT_DESTROY)) {
728 		type = IPCTNL_MSG_CT_DELETE;
729 		group = NFNLGRP_CONNTRACK_DESTROY;
730 	} else if (events & ((1 << IPCT_NEW) | (1 << IPCT_RELATED))) {
731 		type = IPCTNL_MSG_CT_NEW;
732 		flags = NLM_F_CREATE|NLM_F_EXCL;
733 		group = NFNLGRP_CONNTRACK_NEW;
734 	} else if (events) {
735 		type = IPCTNL_MSG_CT_NEW;
736 		group = NFNLGRP_CONNTRACK_UPDATE;
737 	} else
738 		return 0;
739 
740 	net = nf_ct_net(ct);
741 	if (!item->report && !nfnetlink_has_listeners(net, group))
742 		return 0;
743 
744 	skb = nlmsg_new(ctnetlink_nlmsg_size(ct), GFP_ATOMIC);
745 	if (skb == NULL)
746 		goto errout;
747 
748 	type = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, type);
749 	nlh = nfnl_msg_put(skb, item->portid, 0, type, flags, nf_ct_l3num(ct),
750 			   NFNETLINK_V0, 0);
751 	if (!nlh)
752 		goto nlmsg_failure;
753 
754 	zone = nf_ct_zone(ct);
755 
756 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
757 	if (!nest_parms)
758 		goto nla_put_failure;
759 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
760 		goto nla_put_failure;
761 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
762 				   NF_CT_ZONE_DIR_ORIG) < 0)
763 		goto nla_put_failure;
764 	nla_nest_end(skb, nest_parms);
765 
766 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
767 	if (!nest_parms)
768 		goto nla_put_failure;
769 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
770 		goto nla_put_failure;
771 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
772 				   NF_CT_ZONE_DIR_REPL) < 0)
773 		goto nla_put_failure;
774 	nla_nest_end(skb, nest_parms);
775 
776 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
777 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
778 		goto nla_put_failure;
779 
780 	if (ctnetlink_dump_id(skb, ct) < 0)
781 		goto nla_put_failure;
782 
783 	if (ctnetlink_dump_status(skb, ct) < 0)
784 		goto nla_put_failure;
785 
786 	if (events & (1 << IPCT_DESTROY)) {
787 		if (ctnetlink_dump_timeout(skb, ct, true) < 0)
788 			goto nla_put_failure;
789 
790 		if (ctnetlink_dump_acct(skb, ct, type) < 0 ||
791 		    ctnetlink_dump_timestamp(skb, ct) < 0 ||
792 		    ctnetlink_dump_protoinfo(skb, ct, true) < 0)
793 			goto nla_put_failure;
794 	} else {
795 		if (ctnetlink_dump_timeout(skb, ct, false) < 0)
796 			goto nla_put_failure;
797 
798 		if (events & (1 << IPCT_PROTOINFO) &&
799 		    ctnetlink_dump_protoinfo(skb, ct, false) < 0)
800 			goto nla_put_failure;
801 
802 		if ((events & (1 << IPCT_HELPER) || nfct_help(ct))
803 		    && ctnetlink_dump_helpinfo(skb, ct) < 0)
804 			goto nla_put_failure;
805 
806 #ifdef CONFIG_NF_CONNTRACK_SECMARK
807 		if ((events & (1 << IPCT_SECMARK) || ct->secmark)
808 		    && ctnetlink_dump_secctx(skb, ct) < 0)
809 			goto nla_put_failure;
810 #endif
811 		if (events & (1 << IPCT_LABEL) &&
812 		     ctnetlink_dump_labels(skb, ct) < 0)
813 			goto nla_put_failure;
814 
815 		if (events & (1 << IPCT_RELATED) &&
816 		    ctnetlink_dump_master(skb, ct) < 0)
817 			goto nla_put_failure;
818 
819 		if (events & (1 << IPCT_SEQADJ) &&
820 		    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
821 			goto nla_put_failure;
822 
823 		if (events & (1 << IPCT_SYNPROXY) &&
824 		    ctnetlink_dump_ct_synproxy(skb, ct) < 0)
825 			goto nla_put_failure;
826 	}
827 
828 #ifdef CONFIG_NF_CONNTRACK_MARK
829 	if (ctnetlink_dump_mark(skb, ct, events & (1 << IPCT_MARK)))
830 		goto nla_put_failure;
831 #endif
832 	nlmsg_end(skb, nlh);
833 	err = nfnetlink_send(skb, net, item->portid, group, item->report,
834 			     GFP_ATOMIC);
835 	if (err == -ENOBUFS || err == -EAGAIN)
836 		return -ENOBUFS;
837 
838 	return 0;
839 
840 nla_put_failure:
841 	nlmsg_cancel(skb, nlh);
842 nlmsg_failure:
843 	kfree_skb(skb);
844 errout:
845 	if (nfnetlink_set_err(net, 0, group, -ENOBUFS) > 0)
846 		return -ENOBUFS;
847 
848 	return 0;
849 }
850 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
851 
ctnetlink_done(struct netlink_callback * cb)852 static int ctnetlink_done(struct netlink_callback *cb)
853 {
854 	if (cb->args[1])
855 		nf_ct_put((struct nf_conn *)cb->args[1]);
856 	kfree(cb->data);
857 	return 0;
858 }
859 
860 struct ctnetlink_filter_u32 {
861 	u32 val;
862 	u32 mask;
863 };
864 
865 struct ctnetlink_filter {
866 	u8 family;
867 
868 	u_int32_t orig_flags;
869 	u_int32_t reply_flags;
870 
871 	struct nf_conntrack_tuple orig;
872 	struct nf_conntrack_tuple reply;
873 	struct nf_conntrack_zone zone;
874 
875 	struct ctnetlink_filter_u32 mark;
876 	struct ctnetlink_filter_u32 status;
877 };
878 
879 static const struct nla_policy cta_filter_nla_policy[CTA_FILTER_MAX + 1] = {
880 	[CTA_FILTER_ORIG_FLAGS]		= { .type = NLA_U32 },
881 	[CTA_FILTER_REPLY_FLAGS]	= { .type = NLA_U32 },
882 };
883 
ctnetlink_parse_filter(const struct nlattr * attr,struct ctnetlink_filter * filter)884 static int ctnetlink_parse_filter(const struct nlattr *attr,
885 				  struct ctnetlink_filter *filter)
886 {
887 	struct nlattr *tb[CTA_FILTER_MAX + 1];
888 	int ret = 0;
889 
890 	ret = nla_parse_nested(tb, CTA_FILTER_MAX, attr, cta_filter_nla_policy,
891 			       NULL);
892 	if (ret)
893 		return ret;
894 
895 	if (tb[CTA_FILTER_ORIG_FLAGS]) {
896 		filter->orig_flags = nla_get_u32(tb[CTA_FILTER_ORIG_FLAGS]);
897 		if (filter->orig_flags & ~CTA_FILTER_F_ALL)
898 			return -EOPNOTSUPP;
899 	}
900 
901 	if (tb[CTA_FILTER_REPLY_FLAGS]) {
902 		filter->reply_flags = nla_get_u32(tb[CTA_FILTER_REPLY_FLAGS]);
903 		if (filter->reply_flags & ~CTA_FILTER_F_ALL)
904 			return -EOPNOTSUPP;
905 	}
906 
907 	return 0;
908 }
909 
910 static int ctnetlink_parse_zone(const struct nlattr *attr,
911 				struct nf_conntrack_zone *zone);
912 static int ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
913 					 struct nf_conntrack_tuple *tuple,
914 					 u32 type, u_int8_t l3num,
915 					 struct nf_conntrack_zone *zone,
916 					 u_int32_t flags);
917 
ctnetlink_filter_parse_mark(struct ctnetlink_filter_u32 * mark,const struct nlattr * const cda[])918 static int ctnetlink_filter_parse_mark(struct ctnetlink_filter_u32 *mark,
919 				       const struct nlattr * const cda[])
920 {
921 #ifdef CONFIG_NF_CONNTRACK_MARK
922 	if (cda[CTA_MARK]) {
923 		mark->val = ntohl(nla_get_be32(cda[CTA_MARK]));
924 
925 		if (cda[CTA_MARK_MASK])
926 			mark->mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
927 		else
928 			mark->mask = 0xffffffff;
929 	} else if (cda[CTA_MARK_MASK]) {
930 		return -EINVAL;
931 	}
932 #endif
933 	return 0;
934 }
935 
ctnetlink_filter_parse_status(struct ctnetlink_filter_u32 * status,const struct nlattr * const cda[])936 static int ctnetlink_filter_parse_status(struct ctnetlink_filter_u32 *status,
937 					 const struct nlattr * const cda[])
938 {
939 	if (cda[CTA_STATUS]) {
940 		status->val = ntohl(nla_get_be32(cda[CTA_STATUS]));
941 		if (cda[CTA_STATUS_MASK])
942 			status->mask = ntohl(nla_get_be32(cda[CTA_STATUS_MASK]));
943 		else
944 			status->mask = status->val;
945 
946 		/* status->val == 0? always true, else always false. */
947 		if (status->mask == 0)
948 			return -EINVAL;
949 	} else if (cda[CTA_STATUS_MASK]) {
950 		return -EINVAL;
951 	}
952 
953 	/* CTA_STATUS is NLA_U32, if this fires UAPI needs to be extended */
954 	BUILD_BUG_ON(__IPS_MAX_BIT >= 32);
955 	return 0;
956 }
957 
958 static struct ctnetlink_filter *
ctnetlink_alloc_filter(const struct nlattr * const cda[],u8 family)959 ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
960 {
961 	struct ctnetlink_filter *filter;
962 	int err;
963 
964 #ifndef CONFIG_NF_CONNTRACK_MARK
965 	if (cda[CTA_MARK] || cda[CTA_MARK_MASK])
966 		return ERR_PTR(-EOPNOTSUPP);
967 #endif
968 
969 	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
970 	if (filter == NULL)
971 		return ERR_PTR(-ENOMEM);
972 
973 	filter->family = family;
974 
975 	err = ctnetlink_filter_parse_mark(&filter->mark, cda);
976 	if (err)
977 		goto err_filter;
978 
979 	err = ctnetlink_filter_parse_status(&filter->status, cda);
980 	if (err)
981 		goto err_filter;
982 
983 	if (!cda[CTA_FILTER])
984 		return filter;
985 
986 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &filter->zone);
987 	if (err < 0)
988 		goto err_filter;
989 
990 	err = ctnetlink_parse_filter(cda[CTA_FILTER], filter);
991 	if (err < 0)
992 		goto err_filter;
993 
994 	if (filter->orig_flags) {
995 		if (!cda[CTA_TUPLE_ORIG]) {
996 			err = -EINVAL;
997 			goto err_filter;
998 		}
999 
1000 		err = ctnetlink_parse_tuple_filter(cda, &filter->orig,
1001 						   CTA_TUPLE_ORIG,
1002 						   filter->family,
1003 						   &filter->zone,
1004 						   filter->orig_flags);
1005 		if (err < 0)
1006 			goto err_filter;
1007 	}
1008 
1009 	if (filter->reply_flags) {
1010 		if (!cda[CTA_TUPLE_REPLY]) {
1011 			err = -EINVAL;
1012 			goto err_filter;
1013 		}
1014 
1015 		err = ctnetlink_parse_tuple_filter(cda, &filter->reply,
1016 						   CTA_TUPLE_REPLY,
1017 						   filter->family,
1018 						   &filter->zone,
1019 						   filter->reply_flags);
1020 		if (err < 0)
1021 			goto err_filter;
1022 	}
1023 
1024 	return filter;
1025 
1026 err_filter:
1027 	kfree(filter);
1028 
1029 	return ERR_PTR(err);
1030 }
1031 
ctnetlink_needs_filter(u8 family,const struct nlattr * const * cda)1032 static bool ctnetlink_needs_filter(u8 family, const struct nlattr * const *cda)
1033 {
1034 	return family || cda[CTA_MARK] || cda[CTA_FILTER] || cda[CTA_STATUS];
1035 }
1036 
ctnetlink_start(struct netlink_callback * cb)1037 static int ctnetlink_start(struct netlink_callback *cb)
1038 {
1039 	const struct nlattr * const *cda = cb->data;
1040 	struct ctnetlink_filter *filter = NULL;
1041 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1042 	u8 family = nfmsg->nfgen_family;
1043 
1044 	if (ctnetlink_needs_filter(family, cda)) {
1045 		filter = ctnetlink_alloc_filter(cda, family);
1046 		if (IS_ERR(filter))
1047 			return PTR_ERR(filter);
1048 	}
1049 
1050 	cb->data = filter;
1051 	return 0;
1052 }
1053 
ctnetlink_filter_match_tuple(struct nf_conntrack_tuple * filter_tuple,struct nf_conntrack_tuple * ct_tuple,u_int32_t flags,int family)1054 static int ctnetlink_filter_match_tuple(struct nf_conntrack_tuple *filter_tuple,
1055 					struct nf_conntrack_tuple *ct_tuple,
1056 					u_int32_t flags, int family)
1057 {
1058 	switch (family) {
1059 	case NFPROTO_IPV4:
1060 		if ((flags & CTA_FILTER_FLAG(CTA_IP_SRC)) &&
1061 		    filter_tuple->src.u3.ip != ct_tuple->src.u3.ip)
1062 			return  0;
1063 
1064 		if ((flags & CTA_FILTER_FLAG(CTA_IP_DST)) &&
1065 		    filter_tuple->dst.u3.ip != ct_tuple->dst.u3.ip)
1066 			return  0;
1067 		break;
1068 	case NFPROTO_IPV6:
1069 		if ((flags & CTA_FILTER_FLAG(CTA_IP_SRC)) &&
1070 		    !ipv6_addr_cmp(&filter_tuple->src.u3.in6,
1071 				   &ct_tuple->src.u3.in6))
1072 			return 0;
1073 
1074 		if ((flags & CTA_FILTER_FLAG(CTA_IP_DST)) &&
1075 		    !ipv6_addr_cmp(&filter_tuple->dst.u3.in6,
1076 				   &ct_tuple->dst.u3.in6))
1077 			return 0;
1078 		break;
1079 	}
1080 
1081 	if ((flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)) &&
1082 	    filter_tuple->dst.protonum != ct_tuple->dst.protonum)
1083 		return 0;
1084 
1085 	switch (ct_tuple->dst.protonum) {
1086 	case IPPROTO_TCP:
1087 	case IPPROTO_UDP:
1088 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_SRC_PORT)) &&
1089 		    filter_tuple->src.u.tcp.port != ct_tuple->src.u.tcp.port)
1090 			return 0;
1091 
1092 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_DST_PORT)) &&
1093 		    filter_tuple->dst.u.tcp.port != ct_tuple->dst.u.tcp.port)
1094 			return 0;
1095 		break;
1096 	case IPPROTO_ICMP:
1097 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_TYPE)) &&
1098 		    filter_tuple->dst.u.icmp.type != ct_tuple->dst.u.icmp.type)
1099 			return 0;
1100 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_CODE)) &&
1101 		    filter_tuple->dst.u.icmp.code != ct_tuple->dst.u.icmp.code)
1102 			return 0;
1103 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_ID)) &&
1104 		    filter_tuple->src.u.icmp.id != ct_tuple->src.u.icmp.id)
1105 			return 0;
1106 		break;
1107 	case IPPROTO_ICMPV6:
1108 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_TYPE)) &&
1109 		    filter_tuple->dst.u.icmp.type != ct_tuple->dst.u.icmp.type)
1110 			return 0;
1111 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_CODE)) &&
1112 		    filter_tuple->dst.u.icmp.code != ct_tuple->dst.u.icmp.code)
1113 			return 0;
1114 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_ID)) &&
1115 		    filter_tuple->src.u.icmp.id != ct_tuple->src.u.icmp.id)
1116 			return 0;
1117 		break;
1118 	}
1119 
1120 	return 1;
1121 }
1122 
ctnetlink_filter_match(struct nf_conn * ct,void * data)1123 static int ctnetlink_filter_match(struct nf_conn *ct, void *data)
1124 {
1125 	struct ctnetlink_filter *filter = data;
1126 	struct nf_conntrack_tuple *tuple;
1127 	u32 status;
1128 
1129 	if (filter == NULL)
1130 		goto out;
1131 
1132 	/* Match entries of a given L3 protocol number.
1133 	 * If it is not specified, ie. l3proto == 0,
1134 	 * then match everything.
1135 	 */
1136 	if (filter->family && nf_ct_l3num(ct) != filter->family)
1137 		goto ignore_entry;
1138 
1139 	if (filter->orig_flags) {
1140 		tuple = nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL);
1141 		if (!ctnetlink_filter_match_tuple(&filter->orig, tuple,
1142 						  filter->orig_flags,
1143 						  filter->family))
1144 			goto ignore_entry;
1145 	}
1146 
1147 	if (filter->reply_flags) {
1148 		tuple = nf_ct_tuple(ct, IP_CT_DIR_REPLY);
1149 		if (!ctnetlink_filter_match_tuple(&filter->reply, tuple,
1150 						  filter->reply_flags,
1151 						  filter->family))
1152 			goto ignore_entry;
1153 	}
1154 
1155 #ifdef CONFIG_NF_CONNTRACK_MARK
1156 	if ((READ_ONCE(ct->mark) & filter->mark.mask) != filter->mark.val)
1157 		goto ignore_entry;
1158 #endif
1159 	status = (u32)READ_ONCE(ct->status);
1160 	if ((status & filter->status.mask) != filter->status.val)
1161 		goto ignore_entry;
1162 
1163 out:
1164 	return 1;
1165 
1166 ignore_entry:
1167 	return 0;
1168 }
1169 
1170 static int
ctnetlink_dump_table(struct sk_buff * skb,struct netlink_callback * cb)1171 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1172 {
1173 	unsigned int flags = cb->data ? NLM_F_DUMP_FILTERED : 0;
1174 	struct net *net = sock_net(skb->sk);
1175 	struct nf_conn *ct, *last;
1176 	struct nf_conntrack_tuple_hash *h;
1177 	struct hlist_nulls_node *n;
1178 	struct nf_conn *nf_ct_evict[8];
1179 	int res, i;
1180 	spinlock_t *lockp;
1181 
1182 	last = (struct nf_conn *)cb->args[1];
1183 	i = 0;
1184 
1185 	local_bh_disable();
1186 	for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
1187 restart:
1188 		while (i) {
1189 			i--;
1190 			if (nf_ct_should_gc(nf_ct_evict[i]))
1191 				nf_ct_kill(nf_ct_evict[i]);
1192 			nf_ct_put(nf_ct_evict[i]);
1193 		}
1194 
1195 		lockp = &nf_conntrack_locks[cb->args[0] % CONNTRACK_LOCKS];
1196 		nf_conntrack_lock(lockp);
1197 		if (cb->args[0] >= nf_conntrack_htable_size) {
1198 			spin_unlock(lockp);
1199 			goto out;
1200 		}
1201 		hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[cb->args[0]],
1202 					   hnnode) {
1203 			if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
1204 				continue;
1205 			ct = nf_ct_tuplehash_to_ctrack(h);
1206 			if (nf_ct_is_expired(ct)) {
1207 				if (i < ARRAY_SIZE(nf_ct_evict) &&
1208 				    refcount_inc_not_zero(&ct->ct_general.use))
1209 					nf_ct_evict[i++] = ct;
1210 				continue;
1211 			}
1212 
1213 			if (!net_eq(net, nf_ct_net(ct)))
1214 				continue;
1215 
1216 			if (cb->args[1]) {
1217 				if (ct != last)
1218 					continue;
1219 				cb->args[1] = 0;
1220 			}
1221 			if (!ctnetlink_filter_match(ct, cb->data))
1222 				continue;
1223 
1224 			res =
1225 			ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
1226 					    cb->nlh->nlmsg_seq,
1227 					    NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
1228 					    ct, true, flags);
1229 			if (res < 0) {
1230 				nf_conntrack_get(&ct->ct_general);
1231 				cb->args[1] = (unsigned long)ct;
1232 				spin_unlock(lockp);
1233 				goto out;
1234 			}
1235 		}
1236 		spin_unlock(lockp);
1237 		if (cb->args[1]) {
1238 			cb->args[1] = 0;
1239 			goto restart;
1240 		}
1241 	}
1242 out:
1243 	local_bh_enable();
1244 	if (last) {
1245 		/* nf ct hash resize happened, now clear the leftover. */
1246 		if ((struct nf_conn *)cb->args[1] == last)
1247 			cb->args[1] = 0;
1248 
1249 		nf_ct_put(last);
1250 	}
1251 
1252 	while (i) {
1253 		i--;
1254 		if (nf_ct_should_gc(nf_ct_evict[i]))
1255 			nf_ct_kill(nf_ct_evict[i]);
1256 		nf_ct_put(nf_ct_evict[i]);
1257 	}
1258 
1259 	return skb->len;
1260 }
1261 
ipv4_nlattr_to_tuple(struct nlattr * tb[],struct nf_conntrack_tuple * t,u_int32_t flags)1262 static int ipv4_nlattr_to_tuple(struct nlattr *tb[],
1263 				struct nf_conntrack_tuple *t,
1264 				u_int32_t flags)
1265 {
1266 	if (flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1267 		if (!tb[CTA_IP_V4_SRC])
1268 			return -EINVAL;
1269 
1270 		t->src.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_SRC]);
1271 	}
1272 
1273 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST)) {
1274 		if (!tb[CTA_IP_V4_DST])
1275 			return -EINVAL;
1276 
1277 		t->dst.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_DST]);
1278 	}
1279 
1280 	return 0;
1281 }
1282 
ipv6_nlattr_to_tuple(struct nlattr * tb[],struct nf_conntrack_tuple * t,u_int32_t flags)1283 static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
1284 				struct nf_conntrack_tuple *t,
1285 				u_int32_t flags)
1286 {
1287 	if (flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1288 		if (!tb[CTA_IP_V6_SRC])
1289 			return -EINVAL;
1290 
1291 		t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]);
1292 	}
1293 
1294 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST)) {
1295 		if (!tb[CTA_IP_V6_DST])
1296 			return -EINVAL;
1297 
1298 		t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]);
1299 	}
1300 
1301 	return 0;
1302 }
1303 
ctnetlink_parse_tuple_ip(struct nlattr * attr,struct nf_conntrack_tuple * tuple,u_int32_t flags)1304 static int ctnetlink_parse_tuple_ip(struct nlattr *attr,
1305 				    struct nf_conntrack_tuple *tuple,
1306 				    u_int32_t flags)
1307 {
1308 	struct nlattr *tb[CTA_IP_MAX+1];
1309 	int ret = 0;
1310 
1311 	ret = nla_parse_nested_deprecated(tb, CTA_IP_MAX, attr, NULL, NULL);
1312 	if (ret < 0)
1313 		return ret;
1314 
1315 	ret = nla_validate_nested_deprecated(attr, CTA_IP_MAX,
1316 					     cta_ip_nla_policy, NULL);
1317 	if (ret)
1318 		return ret;
1319 
1320 	switch (tuple->src.l3num) {
1321 	case NFPROTO_IPV4:
1322 		ret = ipv4_nlattr_to_tuple(tb, tuple, flags);
1323 		break;
1324 	case NFPROTO_IPV6:
1325 		ret = ipv6_nlattr_to_tuple(tb, tuple, flags);
1326 		break;
1327 	}
1328 
1329 	return ret;
1330 }
1331 
1332 static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
1333 	[CTA_PROTO_NUM]	= { .type = NLA_U8 },
1334 };
1335 
ctnetlink_parse_tuple_proto(struct nlattr * attr,struct nf_conntrack_tuple * tuple,u_int32_t flags)1336 static int ctnetlink_parse_tuple_proto(struct nlattr *attr,
1337 				       struct nf_conntrack_tuple *tuple,
1338 				       u_int32_t flags)
1339 {
1340 	const struct nf_conntrack_l4proto *l4proto;
1341 	struct nlattr *tb[CTA_PROTO_MAX+1];
1342 	int ret = 0;
1343 
1344 	ret = nla_parse_nested_deprecated(tb, CTA_PROTO_MAX, attr,
1345 					  proto_nla_policy, NULL);
1346 	if (ret < 0)
1347 		return ret;
1348 
1349 	if (!(flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)))
1350 		return 0;
1351 
1352 	if (!tb[CTA_PROTO_NUM])
1353 		return -EINVAL;
1354 
1355 	tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
1356 
1357 	rcu_read_lock();
1358 	l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
1359 
1360 	if (likely(l4proto->nlattr_to_tuple)) {
1361 		ret = nla_validate_nested_deprecated(attr, CTA_PROTO_MAX,
1362 						     l4proto->nla_policy,
1363 						     NULL);
1364 		if (ret == 0)
1365 			ret = l4proto->nlattr_to_tuple(tb, tuple, flags);
1366 	}
1367 
1368 	rcu_read_unlock();
1369 
1370 	return ret;
1371 }
1372 
1373 static int
ctnetlink_parse_zone(const struct nlattr * attr,struct nf_conntrack_zone * zone)1374 ctnetlink_parse_zone(const struct nlattr *attr,
1375 		     struct nf_conntrack_zone *zone)
1376 {
1377 	nf_ct_zone_init(zone, NF_CT_DEFAULT_ZONE_ID,
1378 			NF_CT_DEFAULT_ZONE_DIR, 0);
1379 #ifdef CONFIG_NF_CONNTRACK_ZONES
1380 	if (attr)
1381 		zone->id = ntohs(nla_get_be16(attr));
1382 #else
1383 	if (attr)
1384 		return -EOPNOTSUPP;
1385 #endif
1386 	return 0;
1387 }
1388 
1389 static int
ctnetlink_parse_tuple_zone(struct nlattr * attr,enum ctattr_type type,struct nf_conntrack_zone * zone)1390 ctnetlink_parse_tuple_zone(struct nlattr *attr, enum ctattr_type type,
1391 			   struct nf_conntrack_zone *zone)
1392 {
1393 	int ret;
1394 
1395 	if (zone->id != NF_CT_DEFAULT_ZONE_ID)
1396 		return -EINVAL;
1397 
1398 	ret = ctnetlink_parse_zone(attr, zone);
1399 	if (ret < 0)
1400 		return ret;
1401 
1402 	if (type == CTA_TUPLE_REPLY)
1403 		zone->dir = NF_CT_ZONE_DIR_REPL;
1404 	else
1405 		zone->dir = NF_CT_ZONE_DIR_ORIG;
1406 
1407 	return 0;
1408 }
1409 
1410 static const struct nla_policy tuple_nla_policy[CTA_TUPLE_MAX+1] = {
1411 	[CTA_TUPLE_IP]		= { .type = NLA_NESTED },
1412 	[CTA_TUPLE_PROTO]	= { .type = NLA_NESTED },
1413 	[CTA_TUPLE_ZONE]	= { .type = NLA_U16 },
1414 };
1415 
1416 #define CTA_FILTER_F_ALL_CTA_PROTO \
1417   (CTA_FILTER_F_CTA_PROTO_SRC_PORT | \
1418    CTA_FILTER_F_CTA_PROTO_DST_PORT | \
1419    CTA_FILTER_F_CTA_PROTO_ICMP_TYPE | \
1420    CTA_FILTER_F_CTA_PROTO_ICMP_CODE | \
1421    CTA_FILTER_F_CTA_PROTO_ICMP_ID | \
1422    CTA_FILTER_F_CTA_PROTO_ICMPV6_TYPE | \
1423    CTA_FILTER_F_CTA_PROTO_ICMPV6_CODE | \
1424    CTA_FILTER_F_CTA_PROTO_ICMPV6_ID)
1425 
1426 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)1427 ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
1428 			      struct nf_conntrack_tuple *tuple, u32 type,
1429 			      u_int8_t l3num, struct nf_conntrack_zone *zone,
1430 			      u_int32_t flags)
1431 {
1432 	struct nlattr *tb[CTA_TUPLE_MAX+1];
1433 	int err;
1434 
1435 	memset(tuple, 0, sizeof(*tuple));
1436 
1437 	err = nla_parse_nested_deprecated(tb, CTA_TUPLE_MAX, cda[type],
1438 					  tuple_nla_policy, NULL);
1439 	if (err < 0)
1440 		return err;
1441 
1442 	if (l3num != NFPROTO_IPV4 && l3num != NFPROTO_IPV6)
1443 		return -EOPNOTSUPP;
1444 	tuple->src.l3num = l3num;
1445 
1446 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST) ||
1447 	    flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1448 		if (!tb[CTA_TUPLE_IP])
1449 			return -EINVAL;
1450 
1451 		err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple, flags);
1452 		if (err < 0)
1453 			return err;
1454 	}
1455 
1456 	if (flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)) {
1457 		if (!tb[CTA_TUPLE_PROTO])
1458 			return -EINVAL;
1459 
1460 		err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple, flags);
1461 		if (err < 0)
1462 			return err;
1463 	} else if (flags & CTA_FILTER_FLAG(ALL_CTA_PROTO)) {
1464 		/* Can't manage proto flags without a protonum  */
1465 		return -EINVAL;
1466 	}
1467 
1468 	if ((flags & CTA_FILTER_FLAG(CTA_TUPLE_ZONE)) && tb[CTA_TUPLE_ZONE]) {
1469 		if (!zone)
1470 			return -EINVAL;
1471 
1472 		err = ctnetlink_parse_tuple_zone(tb[CTA_TUPLE_ZONE],
1473 						 type, zone);
1474 		if (err < 0)
1475 			return err;
1476 	}
1477 
1478 	/* orig and expect tuples get DIR_ORIGINAL */
1479 	if (type == CTA_TUPLE_REPLY)
1480 		tuple->dst.dir = IP_CT_DIR_REPLY;
1481 	else
1482 		tuple->dst.dir = IP_CT_DIR_ORIGINAL;
1483 
1484 	return 0;
1485 }
1486 
1487 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)1488 ctnetlink_parse_tuple(const struct nlattr * const cda[],
1489 		      struct nf_conntrack_tuple *tuple, u32 type,
1490 		      u_int8_t l3num, struct nf_conntrack_zone *zone)
1491 {
1492 	return ctnetlink_parse_tuple_filter(cda, tuple, type, l3num, zone,
1493 					    CTA_FILTER_FLAG(ALL));
1494 }
1495 
1496 static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = {
1497 	[CTA_HELP_NAME]		= { .type = NLA_NUL_STRING,
1498 				    .len = NF_CT_HELPER_NAME_LEN - 1 },
1499 };
1500 
ctnetlink_parse_help(const struct nlattr * attr,char ** helper_name,struct nlattr ** helpinfo)1501 static int ctnetlink_parse_help(const struct nlattr *attr, char **helper_name,
1502 				struct nlattr **helpinfo)
1503 {
1504 	int err;
1505 	struct nlattr *tb[CTA_HELP_MAX+1];
1506 
1507 	err = nla_parse_nested_deprecated(tb, CTA_HELP_MAX, attr,
1508 					  help_nla_policy, NULL);
1509 	if (err < 0)
1510 		return err;
1511 
1512 	if (!tb[CTA_HELP_NAME])
1513 		return -EINVAL;
1514 
1515 	*helper_name = nla_data(tb[CTA_HELP_NAME]);
1516 
1517 	if (tb[CTA_HELP_INFO])
1518 		*helpinfo = tb[CTA_HELP_INFO];
1519 
1520 	return 0;
1521 }
1522 
1523 static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
1524 	[CTA_TUPLE_ORIG]	= { .type = NLA_NESTED },
1525 	[CTA_TUPLE_REPLY]	= { .type = NLA_NESTED },
1526 	[CTA_STATUS] 		= { .type = NLA_U32 },
1527 	[CTA_PROTOINFO]		= { .type = NLA_NESTED },
1528 	[CTA_HELP]		= { .type = NLA_NESTED },
1529 	[CTA_NAT_SRC]		= { .type = NLA_NESTED },
1530 	[CTA_TIMEOUT] 		= { .type = NLA_U32 },
1531 	[CTA_MARK]		= { .type = NLA_U32 },
1532 	[CTA_ID]		= { .type = NLA_U32 },
1533 	[CTA_NAT_DST]		= { .type = NLA_NESTED },
1534 	[CTA_TUPLE_MASTER]	= { .type = NLA_NESTED },
1535 	[CTA_NAT_SEQ_ADJ_ORIG]  = { .type = NLA_NESTED },
1536 	[CTA_NAT_SEQ_ADJ_REPLY] = { .type = NLA_NESTED },
1537 	[CTA_ZONE]		= { .type = NLA_U16 },
1538 	[CTA_MARK_MASK]		= { .type = NLA_U32 },
1539 	[CTA_LABELS]		= { .type = NLA_BINARY,
1540 				    .len = NF_CT_LABELS_MAX_SIZE },
1541 	[CTA_LABELS_MASK]	= { .type = NLA_BINARY,
1542 				    .len = NF_CT_LABELS_MAX_SIZE },
1543 	[CTA_FILTER]		= { .type = NLA_NESTED },
1544 	[CTA_STATUS_MASK]	= { .type = NLA_U32 },
1545 };
1546 
ctnetlink_flush_iterate(struct nf_conn * ct,void * data)1547 static int ctnetlink_flush_iterate(struct nf_conn *ct, void *data)
1548 {
1549 	return ctnetlink_filter_match(ct, data);
1550 }
1551 
ctnetlink_flush_conntrack(struct net * net,const struct nlattr * const cda[],u32 portid,int report,u8 family)1552 static int ctnetlink_flush_conntrack(struct net *net,
1553 				     const struct nlattr * const cda[],
1554 				     u32 portid, int report, u8 family)
1555 {
1556 	struct ctnetlink_filter *filter = NULL;
1557 
1558 	if (ctnetlink_needs_filter(family, cda)) {
1559 		if (cda[CTA_FILTER])
1560 			return -EOPNOTSUPP;
1561 
1562 		filter = ctnetlink_alloc_filter(cda, family);
1563 		if (IS_ERR(filter))
1564 			return PTR_ERR(filter);
1565 	}
1566 
1567 	nf_ct_iterate_cleanup_net(net, ctnetlink_flush_iterate, filter,
1568 				  portid, report);
1569 	kfree(filter);
1570 
1571 	return 0;
1572 }
1573 
ctnetlink_del_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1574 static int ctnetlink_del_conntrack(struct sk_buff *skb,
1575 				   const struct nfnl_info *info,
1576 				   const struct nlattr * const cda[])
1577 {
1578 	u8 family = info->nfmsg->nfgen_family;
1579 	struct nf_conntrack_tuple_hash *h;
1580 	struct nf_conntrack_tuple tuple;
1581 	struct nf_conntrack_zone zone;
1582 	struct nf_conn *ct;
1583 	int err;
1584 
1585 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1586 	if (err < 0)
1587 		return err;
1588 
1589 	if (cda[CTA_TUPLE_ORIG])
1590 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG,
1591 					    family, &zone);
1592 	else if (cda[CTA_TUPLE_REPLY])
1593 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY,
1594 					    family, &zone);
1595 	else {
1596 		u_int8_t u3 = info->nfmsg->version ? family : AF_UNSPEC;
1597 
1598 		return ctnetlink_flush_conntrack(info->net, cda,
1599 						 NETLINK_CB(skb).portid,
1600 						 nlmsg_report(info->nlh), u3);
1601 	}
1602 
1603 	if (err < 0)
1604 		return err;
1605 
1606 	h = nf_conntrack_find_get(info->net, &zone, &tuple);
1607 	if (!h)
1608 		return -ENOENT;
1609 
1610 	ct = nf_ct_tuplehash_to_ctrack(h);
1611 
1612 	if (cda[CTA_ID]) {
1613 		__be32 id = nla_get_be32(cda[CTA_ID]);
1614 
1615 		if (id != (__force __be32)nf_ct_get_id(ct)) {
1616 			nf_ct_put(ct);
1617 			return -ENOENT;
1618 		}
1619 	}
1620 
1621 	nf_ct_delete(ct, NETLINK_CB(skb).portid, nlmsg_report(info->nlh));
1622 	nf_ct_put(ct);
1623 
1624 	return 0;
1625 }
1626 
ctnetlink_get_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1627 static int ctnetlink_get_conntrack(struct sk_buff *skb,
1628 				   const struct nfnl_info *info,
1629 				   const struct nlattr * const cda[])
1630 {
1631 	u_int8_t u3 = info->nfmsg->nfgen_family;
1632 	struct nf_conntrack_tuple_hash *h;
1633 	struct nf_conntrack_tuple tuple;
1634 	struct nf_conntrack_zone zone;
1635 	struct sk_buff *skb2;
1636 	struct nf_conn *ct;
1637 	int err;
1638 
1639 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1640 		struct netlink_dump_control c = {
1641 			.start = ctnetlink_start,
1642 			.dump = ctnetlink_dump_table,
1643 			.done = ctnetlink_done,
1644 			.data = (void *)cda,
1645 		};
1646 
1647 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1648 	}
1649 
1650 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1651 	if (err < 0)
1652 		return err;
1653 
1654 	if (cda[CTA_TUPLE_ORIG])
1655 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG,
1656 					    u3, &zone);
1657 	else if (cda[CTA_TUPLE_REPLY])
1658 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY,
1659 					    u3, &zone);
1660 	else
1661 		return -EINVAL;
1662 
1663 	if (err < 0)
1664 		return err;
1665 
1666 	h = nf_conntrack_find_get(info->net, &zone, &tuple);
1667 	if (!h)
1668 		return -ENOENT;
1669 
1670 	ct = nf_ct_tuplehash_to_ctrack(h);
1671 
1672 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1673 	if (!skb2) {
1674 		nf_ct_put(ct);
1675 		return -ENOMEM;
1676 	}
1677 
1678 	err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).portid,
1679 				  info->nlh->nlmsg_seq,
1680 				  NFNL_MSG_TYPE(info->nlh->nlmsg_type), ct,
1681 				  true, 0);
1682 	nf_ct_put(ct);
1683 	if (err <= 0) {
1684 		kfree_skb(skb2);
1685 		return -ENOMEM;
1686 	}
1687 
1688 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
1689 }
1690 
ctnetlink_done_list(struct netlink_callback * cb)1691 static int ctnetlink_done_list(struct netlink_callback *cb)
1692 {
1693 	if (cb->args[1])
1694 		nf_ct_put((struct nf_conn *)cb->args[1]);
1695 	return 0;
1696 }
1697 
1698 static int
ctnetlink_dump_list(struct sk_buff * skb,struct netlink_callback * cb,bool dying)1699 ctnetlink_dump_list(struct sk_buff *skb, struct netlink_callback *cb, bool dying)
1700 {
1701 	struct nf_conn *ct, *last;
1702 	struct nf_conntrack_tuple_hash *h;
1703 	struct hlist_nulls_node *n;
1704 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1705 	u_int8_t l3proto = nfmsg->nfgen_family;
1706 	int res;
1707 	int cpu;
1708 	struct hlist_nulls_head *list;
1709 	struct net *net = sock_net(skb->sk);
1710 
1711 	if (cb->args[2])
1712 		return 0;
1713 
1714 	last = (struct nf_conn *)cb->args[1];
1715 
1716 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
1717 		struct ct_pcpu *pcpu;
1718 
1719 		if (!cpu_possible(cpu))
1720 			continue;
1721 
1722 		pcpu = per_cpu_ptr(net->ct.pcpu_lists, cpu);
1723 		spin_lock_bh(&pcpu->lock);
1724 		list = dying ? &pcpu->dying : &pcpu->unconfirmed;
1725 restart:
1726 		hlist_nulls_for_each_entry(h, n, list, hnnode) {
1727 			ct = nf_ct_tuplehash_to_ctrack(h);
1728 			if (l3proto && nf_ct_l3num(ct) != l3proto)
1729 				continue;
1730 			if (cb->args[1]) {
1731 				if (ct != last)
1732 					continue;
1733 				cb->args[1] = 0;
1734 			}
1735 
1736 			/* We can't dump extension info for the unconfirmed
1737 			 * list because unconfirmed conntracks can have
1738 			 * ct->ext reallocated (and thus freed).
1739 			 *
1740 			 * In the dying list case ct->ext can't be free'd
1741 			 * until after we drop pcpu->lock.
1742 			 */
1743 			res = ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
1744 						  cb->nlh->nlmsg_seq,
1745 						  NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
1746 						  ct, dying ? true : false, 0);
1747 			if (res < 0) {
1748 				if (!refcount_inc_not_zero(&ct->ct_general.use))
1749 					continue;
1750 				cb->args[0] = cpu;
1751 				cb->args[1] = (unsigned long)ct;
1752 				spin_unlock_bh(&pcpu->lock);
1753 				goto out;
1754 			}
1755 		}
1756 		if (cb->args[1]) {
1757 			cb->args[1] = 0;
1758 			goto restart;
1759 		}
1760 		spin_unlock_bh(&pcpu->lock);
1761 	}
1762 	cb->args[2] = 1;
1763 out:
1764 	if (last)
1765 		nf_ct_put(last);
1766 
1767 	return skb->len;
1768 }
1769 
1770 static int
ctnetlink_dump_dying(struct sk_buff * skb,struct netlink_callback * cb)1771 ctnetlink_dump_dying(struct sk_buff *skb, struct netlink_callback *cb)
1772 {
1773 	return ctnetlink_dump_list(skb, cb, true);
1774 }
1775 
ctnetlink_get_ct_dying(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1776 static int ctnetlink_get_ct_dying(struct sk_buff *skb,
1777 				  const struct nfnl_info *info,
1778 				  const struct nlattr * const cda[])
1779 {
1780 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1781 		struct netlink_dump_control c = {
1782 			.dump = ctnetlink_dump_dying,
1783 			.done = ctnetlink_done_list,
1784 		};
1785 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1786 	}
1787 
1788 	return -EOPNOTSUPP;
1789 }
1790 
1791 static int
ctnetlink_dump_unconfirmed(struct sk_buff * skb,struct netlink_callback * cb)1792 ctnetlink_dump_unconfirmed(struct sk_buff *skb, struct netlink_callback *cb)
1793 {
1794 	return ctnetlink_dump_list(skb, cb, false);
1795 }
1796 
ctnetlink_get_ct_unconfirmed(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1797 static int ctnetlink_get_ct_unconfirmed(struct sk_buff *skb,
1798 					const struct nfnl_info *info,
1799 					const struct nlattr * const cda[])
1800 {
1801 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1802 		struct netlink_dump_control c = {
1803 			.dump = ctnetlink_dump_unconfirmed,
1804 			.done = ctnetlink_done_list,
1805 		};
1806 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1807 	}
1808 
1809 	return -EOPNOTSUPP;
1810 }
1811 
1812 #if IS_ENABLED(CONFIG_NF_NAT)
1813 static int
ctnetlink_parse_nat_setup(struct nf_conn * ct,enum nf_nat_manip_type manip,const struct nlattr * attr)1814 ctnetlink_parse_nat_setup(struct nf_conn *ct,
1815 			  enum nf_nat_manip_type manip,
1816 			  const struct nlattr *attr)
1817 	__must_hold(RCU)
1818 {
1819 	struct nf_nat_hook *nat_hook;
1820 	int err;
1821 
1822 	nat_hook = rcu_dereference(nf_nat_hook);
1823 	if (!nat_hook) {
1824 #ifdef CONFIG_MODULES
1825 		rcu_read_unlock();
1826 		nfnl_unlock(NFNL_SUBSYS_CTNETLINK);
1827 		if (request_module("nf-nat") < 0) {
1828 			nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1829 			rcu_read_lock();
1830 			return -EOPNOTSUPP;
1831 		}
1832 		nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1833 		rcu_read_lock();
1834 		nat_hook = rcu_dereference(nf_nat_hook);
1835 		if (nat_hook)
1836 			return -EAGAIN;
1837 #endif
1838 		return -EOPNOTSUPP;
1839 	}
1840 
1841 	err = nat_hook->parse_nat_setup(ct, manip, attr);
1842 	if (err == -EAGAIN) {
1843 #ifdef CONFIG_MODULES
1844 		rcu_read_unlock();
1845 		nfnl_unlock(NFNL_SUBSYS_CTNETLINK);
1846 		if (request_module("nf-nat-%u", nf_ct_l3num(ct)) < 0) {
1847 			nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1848 			rcu_read_lock();
1849 			return -EOPNOTSUPP;
1850 		}
1851 		nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1852 		rcu_read_lock();
1853 #else
1854 		err = -EOPNOTSUPP;
1855 #endif
1856 	}
1857 	return err;
1858 }
1859 #endif
1860 
1861 static void
__ctnetlink_change_status(struct nf_conn * ct,unsigned long on,unsigned long off)1862 __ctnetlink_change_status(struct nf_conn *ct, unsigned long on,
1863 			  unsigned long off)
1864 {
1865 	unsigned int bit;
1866 
1867 	/* Ignore these unchangable bits */
1868 	on &= ~IPS_UNCHANGEABLE_MASK;
1869 	off &= ~IPS_UNCHANGEABLE_MASK;
1870 
1871 	for (bit = 0; bit < __IPS_MAX_BIT; bit++) {
1872 		if (on & (1 << bit))
1873 			set_bit(bit, &ct->status);
1874 		else if (off & (1 << bit))
1875 			clear_bit(bit, &ct->status);
1876 	}
1877 }
1878 
1879 static int
ctnetlink_change_status(struct nf_conn * ct,const struct nlattr * const cda[])1880 ctnetlink_change_status(struct nf_conn *ct, const struct nlattr * const cda[])
1881 {
1882 	unsigned long d;
1883 	unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
1884 	d = ct->status ^ status;
1885 
1886 	if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
1887 		/* unchangeable */
1888 		return -EBUSY;
1889 
1890 	if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
1891 		/* SEEN_REPLY bit can only be set */
1892 		return -EBUSY;
1893 
1894 	if (d & IPS_ASSURED && !(status & IPS_ASSURED))
1895 		/* ASSURED bit can only be set */
1896 		return -EBUSY;
1897 
1898 	__ctnetlink_change_status(ct, status, 0);
1899 	return 0;
1900 }
1901 
1902 static int
ctnetlink_setup_nat(struct nf_conn * ct,const struct nlattr * const cda[])1903 ctnetlink_setup_nat(struct nf_conn *ct, const struct nlattr * const cda[])
1904 {
1905 #if IS_ENABLED(CONFIG_NF_NAT)
1906 	int ret;
1907 
1908 	if (!cda[CTA_NAT_DST] && !cda[CTA_NAT_SRC])
1909 		return 0;
1910 
1911 	ret = ctnetlink_parse_nat_setup(ct, NF_NAT_MANIP_DST,
1912 					cda[CTA_NAT_DST]);
1913 	if (ret < 0)
1914 		return ret;
1915 
1916 	return ctnetlink_parse_nat_setup(ct, NF_NAT_MANIP_SRC,
1917 					 cda[CTA_NAT_SRC]);
1918 #else
1919 	if (!cda[CTA_NAT_DST] && !cda[CTA_NAT_SRC])
1920 		return 0;
1921 	return -EOPNOTSUPP;
1922 #endif
1923 }
1924 
ctnetlink_change_helper(struct nf_conn * ct,const struct nlattr * const cda[])1925 static int ctnetlink_change_helper(struct nf_conn *ct,
1926 				   const struct nlattr * const cda[])
1927 {
1928 	struct nf_conntrack_helper *helper;
1929 	struct nf_conn_help *help = nfct_help(ct);
1930 	char *helpname = NULL;
1931 	struct nlattr *helpinfo = NULL;
1932 	int err;
1933 
1934 	err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
1935 	if (err < 0)
1936 		return err;
1937 
1938 	/* don't change helper of sibling connections */
1939 	if (ct->master) {
1940 		/* If we try to change the helper to the same thing twice,
1941 		 * treat the second attempt as a no-op instead of returning
1942 		 * an error.
1943 		 */
1944 		err = -EBUSY;
1945 		if (help) {
1946 			rcu_read_lock();
1947 			helper = rcu_dereference(help->helper);
1948 			if (helper && !strcmp(helper->name, helpname))
1949 				err = 0;
1950 			rcu_read_unlock();
1951 		}
1952 
1953 		return err;
1954 	}
1955 
1956 	if (!strcmp(helpname, "")) {
1957 		if (help && help->helper) {
1958 			/* we had a helper before ... */
1959 			nf_ct_remove_expectations(ct);
1960 			RCU_INIT_POINTER(help->helper, NULL);
1961 		}
1962 
1963 		return 0;
1964 	}
1965 
1966 	rcu_read_lock();
1967 	helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
1968 					    nf_ct_protonum(ct));
1969 	if (helper == NULL) {
1970 		rcu_read_unlock();
1971 		return -EOPNOTSUPP;
1972 	}
1973 
1974 	if (help) {
1975 		if (help->helper == helper) {
1976 			/* update private helper data if allowed. */
1977 			if (helper->from_nlattr)
1978 				helper->from_nlattr(helpinfo, ct);
1979 			err = 0;
1980 		} else
1981 			err = -EBUSY;
1982 	} else {
1983 		/* we cannot set a helper for an existing conntrack */
1984 		err = -EOPNOTSUPP;
1985 	}
1986 
1987 	rcu_read_unlock();
1988 	return err;
1989 }
1990 
ctnetlink_change_timeout(struct nf_conn * ct,const struct nlattr * const cda[])1991 static int ctnetlink_change_timeout(struct nf_conn *ct,
1992 				    const struct nlattr * const cda[])
1993 {
1994 	u64 timeout = (u64)ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ;
1995 
1996 	if (timeout > INT_MAX)
1997 		timeout = INT_MAX;
1998 	WRITE_ONCE(ct->timeout, nfct_time_stamp + (u32)timeout);
1999 
2000 	if (test_bit(IPS_DYING_BIT, &ct->status))
2001 		return -ETIME;
2002 
2003 	return 0;
2004 }
2005 
2006 #if defined(CONFIG_NF_CONNTRACK_MARK)
ctnetlink_change_mark(struct nf_conn * ct,const struct nlattr * const cda[])2007 static void ctnetlink_change_mark(struct nf_conn *ct,
2008 				    const struct nlattr * const cda[])
2009 {
2010 	u32 mark, newmark, mask = 0;
2011 
2012 	if (cda[CTA_MARK_MASK])
2013 		mask = ~ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
2014 
2015 	mark = ntohl(nla_get_be32(cda[CTA_MARK]));
2016 	newmark = (READ_ONCE(ct->mark) & mask) ^ mark;
2017 	if (newmark != READ_ONCE(ct->mark))
2018 		WRITE_ONCE(ct->mark, newmark);
2019 }
2020 #endif
2021 
2022 static const struct nla_policy protoinfo_policy[CTA_PROTOINFO_MAX+1] = {
2023 	[CTA_PROTOINFO_TCP]	= { .type = NLA_NESTED },
2024 	[CTA_PROTOINFO_DCCP]	= { .type = NLA_NESTED },
2025 	[CTA_PROTOINFO_SCTP]	= { .type = NLA_NESTED },
2026 };
2027 
ctnetlink_change_protoinfo(struct nf_conn * ct,const struct nlattr * const cda[])2028 static int ctnetlink_change_protoinfo(struct nf_conn *ct,
2029 				      const struct nlattr * const cda[])
2030 {
2031 	const struct nlattr *attr = cda[CTA_PROTOINFO];
2032 	const struct nf_conntrack_l4proto *l4proto;
2033 	struct nlattr *tb[CTA_PROTOINFO_MAX+1];
2034 	int err = 0;
2035 
2036 	err = nla_parse_nested_deprecated(tb, CTA_PROTOINFO_MAX, attr,
2037 					  protoinfo_policy, NULL);
2038 	if (err < 0)
2039 		return err;
2040 
2041 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
2042 	if (l4proto->from_nlattr)
2043 		err = l4proto->from_nlattr(tb, ct);
2044 
2045 	return err;
2046 }
2047 
2048 static const struct nla_policy seqadj_policy[CTA_SEQADJ_MAX+1] = {
2049 	[CTA_SEQADJ_CORRECTION_POS]	= { .type = NLA_U32 },
2050 	[CTA_SEQADJ_OFFSET_BEFORE]	= { .type = NLA_U32 },
2051 	[CTA_SEQADJ_OFFSET_AFTER]	= { .type = NLA_U32 },
2052 };
2053 
change_seq_adj(struct nf_ct_seqadj * seq,const struct nlattr * const attr)2054 static int change_seq_adj(struct nf_ct_seqadj *seq,
2055 			  const struct nlattr * const attr)
2056 {
2057 	int err;
2058 	struct nlattr *cda[CTA_SEQADJ_MAX+1];
2059 
2060 	err = nla_parse_nested_deprecated(cda, CTA_SEQADJ_MAX, attr,
2061 					  seqadj_policy, NULL);
2062 	if (err < 0)
2063 		return err;
2064 
2065 	if (!cda[CTA_SEQADJ_CORRECTION_POS])
2066 		return -EINVAL;
2067 
2068 	seq->correction_pos =
2069 		ntohl(nla_get_be32(cda[CTA_SEQADJ_CORRECTION_POS]));
2070 
2071 	if (!cda[CTA_SEQADJ_OFFSET_BEFORE])
2072 		return -EINVAL;
2073 
2074 	seq->offset_before =
2075 		ntohl(nla_get_be32(cda[CTA_SEQADJ_OFFSET_BEFORE]));
2076 
2077 	if (!cda[CTA_SEQADJ_OFFSET_AFTER])
2078 		return -EINVAL;
2079 
2080 	seq->offset_after =
2081 		ntohl(nla_get_be32(cda[CTA_SEQADJ_OFFSET_AFTER]));
2082 
2083 	return 0;
2084 }
2085 
2086 static int
ctnetlink_change_seq_adj(struct nf_conn * ct,const struct nlattr * const cda[])2087 ctnetlink_change_seq_adj(struct nf_conn *ct,
2088 			 const struct nlattr * const cda[])
2089 {
2090 	struct nf_conn_seqadj *seqadj = nfct_seqadj(ct);
2091 	int ret = 0;
2092 
2093 	if (!seqadj)
2094 		return 0;
2095 
2096 	spin_lock_bh(&ct->lock);
2097 	if (cda[CTA_SEQ_ADJ_ORIG]) {
2098 		ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_ORIGINAL],
2099 				     cda[CTA_SEQ_ADJ_ORIG]);
2100 		if (ret < 0)
2101 			goto err;
2102 
2103 		set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
2104 	}
2105 
2106 	if (cda[CTA_SEQ_ADJ_REPLY]) {
2107 		ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_REPLY],
2108 				     cda[CTA_SEQ_ADJ_REPLY]);
2109 		if (ret < 0)
2110 			goto err;
2111 
2112 		set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
2113 	}
2114 
2115 	spin_unlock_bh(&ct->lock);
2116 	return 0;
2117 err:
2118 	spin_unlock_bh(&ct->lock);
2119 	return ret;
2120 }
2121 
2122 static const struct nla_policy synproxy_policy[CTA_SYNPROXY_MAX + 1] = {
2123 	[CTA_SYNPROXY_ISN]	= { .type = NLA_U32 },
2124 	[CTA_SYNPROXY_ITS]	= { .type = NLA_U32 },
2125 	[CTA_SYNPROXY_TSOFF]	= { .type = NLA_U32 },
2126 };
2127 
ctnetlink_change_synproxy(struct nf_conn * ct,const struct nlattr * const cda[])2128 static int ctnetlink_change_synproxy(struct nf_conn *ct,
2129 				     const struct nlattr * const cda[])
2130 {
2131 	struct nf_conn_synproxy *synproxy = nfct_synproxy(ct);
2132 	struct nlattr *tb[CTA_SYNPROXY_MAX + 1];
2133 	int err;
2134 
2135 	if (!synproxy)
2136 		return 0;
2137 
2138 	err = nla_parse_nested_deprecated(tb, CTA_SYNPROXY_MAX,
2139 					  cda[CTA_SYNPROXY], synproxy_policy,
2140 					  NULL);
2141 	if (err < 0)
2142 		return err;
2143 
2144 	if (!tb[CTA_SYNPROXY_ISN] ||
2145 	    !tb[CTA_SYNPROXY_ITS] ||
2146 	    !tb[CTA_SYNPROXY_TSOFF])
2147 		return -EINVAL;
2148 
2149 	synproxy->isn = ntohl(nla_get_be32(tb[CTA_SYNPROXY_ISN]));
2150 	synproxy->its = ntohl(nla_get_be32(tb[CTA_SYNPROXY_ITS]));
2151 	synproxy->tsoff = ntohl(nla_get_be32(tb[CTA_SYNPROXY_TSOFF]));
2152 
2153 	return 0;
2154 }
2155 
2156 static int
ctnetlink_attach_labels(struct nf_conn * ct,const struct nlattr * const cda[])2157 ctnetlink_attach_labels(struct nf_conn *ct, const struct nlattr * const cda[])
2158 {
2159 #ifdef CONFIG_NF_CONNTRACK_LABELS
2160 	size_t len = nla_len(cda[CTA_LABELS]);
2161 	const void *mask = cda[CTA_LABELS_MASK];
2162 
2163 	if (len & (sizeof(u32)-1)) /* must be multiple of u32 */
2164 		return -EINVAL;
2165 
2166 	if (mask) {
2167 		if (nla_len(cda[CTA_LABELS_MASK]) == 0 ||
2168 		    nla_len(cda[CTA_LABELS_MASK]) != len)
2169 			return -EINVAL;
2170 		mask = nla_data(cda[CTA_LABELS_MASK]);
2171 	}
2172 
2173 	len /= sizeof(u32);
2174 
2175 	return nf_connlabels_replace(ct, nla_data(cda[CTA_LABELS]), mask, len);
2176 #else
2177 	return -EOPNOTSUPP;
2178 #endif
2179 }
2180 
2181 static int
ctnetlink_change_conntrack(struct nf_conn * ct,const struct nlattr * const cda[])2182 ctnetlink_change_conntrack(struct nf_conn *ct,
2183 			   const struct nlattr * const cda[])
2184 {
2185 	int err;
2186 
2187 	/* only allow NAT changes and master assignation for new conntracks */
2188 	if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST] || cda[CTA_TUPLE_MASTER])
2189 		return -EOPNOTSUPP;
2190 
2191 	if (cda[CTA_HELP]) {
2192 		err = ctnetlink_change_helper(ct, cda);
2193 		if (err < 0)
2194 			return err;
2195 	}
2196 
2197 	if (cda[CTA_TIMEOUT]) {
2198 		err = ctnetlink_change_timeout(ct, cda);
2199 		if (err < 0)
2200 			return err;
2201 	}
2202 
2203 	if (cda[CTA_STATUS]) {
2204 		err = ctnetlink_change_status(ct, cda);
2205 		if (err < 0)
2206 			return err;
2207 	}
2208 
2209 	if (cda[CTA_PROTOINFO]) {
2210 		err = ctnetlink_change_protoinfo(ct, cda);
2211 		if (err < 0)
2212 			return err;
2213 	}
2214 
2215 #if defined(CONFIG_NF_CONNTRACK_MARK)
2216 	if (cda[CTA_MARK])
2217 		ctnetlink_change_mark(ct, cda);
2218 #endif
2219 
2220 	if (cda[CTA_SEQ_ADJ_ORIG] || cda[CTA_SEQ_ADJ_REPLY]) {
2221 		err = ctnetlink_change_seq_adj(ct, cda);
2222 		if (err < 0)
2223 			return err;
2224 	}
2225 
2226 	if (cda[CTA_SYNPROXY]) {
2227 		err = ctnetlink_change_synproxy(ct, cda);
2228 		if (err < 0)
2229 			return err;
2230 	}
2231 
2232 	if (cda[CTA_LABELS]) {
2233 		err = ctnetlink_attach_labels(ct, cda);
2234 		if (err < 0)
2235 			return err;
2236 	}
2237 
2238 	return 0;
2239 }
2240 
2241 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)2242 ctnetlink_create_conntrack(struct net *net,
2243 			   const struct nf_conntrack_zone *zone,
2244 			   const struct nlattr * const cda[],
2245 			   struct nf_conntrack_tuple *otuple,
2246 			   struct nf_conntrack_tuple *rtuple,
2247 			   u8 u3)
2248 {
2249 	struct nf_conn *ct;
2250 	int err = -EINVAL;
2251 	struct nf_conntrack_helper *helper;
2252 	struct nf_conn_tstamp *tstamp;
2253 	u64 timeout;
2254 
2255 	ct = nf_conntrack_alloc(net, zone, otuple, rtuple, GFP_ATOMIC);
2256 	if (IS_ERR(ct))
2257 		return ERR_PTR(-ENOMEM);
2258 
2259 	if (!cda[CTA_TIMEOUT])
2260 		goto err1;
2261 
2262 	timeout = (u64)ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ;
2263 	if (timeout > INT_MAX)
2264 		timeout = INT_MAX;
2265 	ct->timeout = (u32)timeout + nfct_time_stamp;
2266 
2267 	rcu_read_lock();
2268  	if (cda[CTA_HELP]) {
2269 		char *helpname = NULL;
2270 		struct nlattr *helpinfo = NULL;
2271 
2272 		err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
2273  		if (err < 0)
2274 			goto err2;
2275 
2276 		helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
2277 						    nf_ct_protonum(ct));
2278 		if (helper == NULL) {
2279 			rcu_read_unlock();
2280 #ifdef CONFIG_MODULES
2281 			if (request_module("nfct-helper-%s", helpname) < 0) {
2282 				err = -EOPNOTSUPP;
2283 				goto err1;
2284 			}
2285 
2286 			rcu_read_lock();
2287 			helper = __nf_conntrack_helper_find(helpname,
2288 							    nf_ct_l3num(ct),
2289 							    nf_ct_protonum(ct));
2290 			if (helper) {
2291 				err = -EAGAIN;
2292 				goto err2;
2293 			}
2294 			rcu_read_unlock();
2295 #endif
2296 			err = -EOPNOTSUPP;
2297 			goto err1;
2298 		} else {
2299 			struct nf_conn_help *help;
2300 
2301 			help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
2302 			if (help == NULL) {
2303 				err = -ENOMEM;
2304 				goto err2;
2305 			}
2306 			/* set private helper data if allowed. */
2307 			if (helper->from_nlattr)
2308 				helper->from_nlattr(helpinfo, ct);
2309 
2310 			/* disable helper auto-assignment for this entry */
2311 			ct->status |= IPS_HELPER;
2312 			RCU_INIT_POINTER(help->helper, helper);
2313 		}
2314 	} else {
2315 		/* try an implicit helper assignation */
2316 		err = __nf_ct_try_assign_helper(ct, NULL, GFP_ATOMIC);
2317 		if (err < 0)
2318 			goto err2;
2319 	}
2320 
2321 	err = ctnetlink_setup_nat(ct, cda);
2322 	if (err < 0)
2323 		goto err2;
2324 
2325 	nf_ct_acct_ext_add(ct, GFP_ATOMIC);
2326 	nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
2327 	nf_ct_ecache_ext_add(ct, 0, 0, GFP_ATOMIC);
2328 	nf_ct_labels_ext_add(ct);
2329 	nfct_seqadj_ext_add(ct);
2330 	nfct_synproxy_ext_add(ct);
2331 
2332 	/* we must add conntrack extensions before confirmation. */
2333 	ct->status |= IPS_CONFIRMED;
2334 
2335 	if (cda[CTA_STATUS]) {
2336 		err = ctnetlink_change_status(ct, cda);
2337 		if (err < 0)
2338 			goto err2;
2339 	}
2340 
2341 	if (cda[CTA_SEQ_ADJ_ORIG] || cda[CTA_SEQ_ADJ_REPLY]) {
2342 		err = ctnetlink_change_seq_adj(ct, cda);
2343 		if (err < 0)
2344 			goto err2;
2345 	}
2346 
2347 	memset(&ct->proto, 0, sizeof(ct->proto));
2348 	if (cda[CTA_PROTOINFO]) {
2349 		err = ctnetlink_change_protoinfo(ct, cda);
2350 		if (err < 0)
2351 			goto err2;
2352 	}
2353 
2354 	if (cda[CTA_SYNPROXY]) {
2355 		err = ctnetlink_change_synproxy(ct, cda);
2356 		if (err < 0)
2357 			goto err2;
2358 	}
2359 
2360 #if defined(CONFIG_NF_CONNTRACK_MARK)
2361 	if (cda[CTA_MARK])
2362 		ctnetlink_change_mark(ct, cda);
2363 #endif
2364 
2365 	/* setup master conntrack: this is a confirmed expectation */
2366 	if (cda[CTA_TUPLE_MASTER]) {
2367 		struct nf_conntrack_tuple master;
2368 		struct nf_conntrack_tuple_hash *master_h;
2369 		struct nf_conn *master_ct;
2370 
2371 		err = ctnetlink_parse_tuple(cda, &master, CTA_TUPLE_MASTER,
2372 					    u3, NULL);
2373 		if (err < 0)
2374 			goto err2;
2375 
2376 		master_h = nf_conntrack_find_get(net, zone, &master);
2377 		if (master_h == NULL) {
2378 			err = -ENOENT;
2379 			goto err2;
2380 		}
2381 		master_ct = nf_ct_tuplehash_to_ctrack(master_h);
2382 		__set_bit(IPS_EXPECTED_BIT, &ct->status);
2383 		ct->master = master_ct;
2384 	}
2385 	tstamp = nf_conn_tstamp_find(ct);
2386 	if (tstamp)
2387 		tstamp->start = ktime_get_real_ns();
2388 
2389 	err = nf_conntrack_hash_check_insert(ct);
2390 	if (err < 0)
2391 		goto err3;
2392 
2393 	rcu_read_unlock();
2394 
2395 	return ct;
2396 
2397 err3:
2398 	if (ct->master)
2399 		nf_ct_put(ct->master);
2400 err2:
2401 	rcu_read_unlock();
2402 err1:
2403 	nf_conntrack_free(ct);
2404 	return ERR_PTR(err);
2405 }
2406 
ctnetlink_new_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2407 static int ctnetlink_new_conntrack(struct sk_buff *skb,
2408 				   const struct nfnl_info *info,
2409 				   const struct nlattr * const cda[])
2410 {
2411 	struct nf_conntrack_tuple otuple, rtuple;
2412 	struct nf_conntrack_tuple_hash *h = NULL;
2413 	u_int8_t u3 = info->nfmsg->nfgen_family;
2414 	struct nf_conntrack_zone zone;
2415 	struct nf_conn *ct;
2416 	int err;
2417 
2418 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
2419 	if (err < 0)
2420 		return err;
2421 
2422 	if (cda[CTA_TUPLE_ORIG]) {
2423 		err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG,
2424 					    u3, &zone);
2425 		if (err < 0)
2426 			return err;
2427 	}
2428 
2429 	if (cda[CTA_TUPLE_REPLY]) {
2430 		err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY,
2431 					    u3, &zone);
2432 		if (err < 0)
2433 			return err;
2434 	}
2435 
2436 	if (cda[CTA_TUPLE_ORIG])
2437 		h = nf_conntrack_find_get(info->net, &zone, &otuple);
2438 	else if (cda[CTA_TUPLE_REPLY])
2439 		h = nf_conntrack_find_get(info->net, &zone, &rtuple);
2440 
2441 	if (h == NULL) {
2442 		err = -ENOENT;
2443 		if (info->nlh->nlmsg_flags & NLM_F_CREATE) {
2444 			enum ip_conntrack_events events;
2445 
2446 			if (!cda[CTA_TUPLE_ORIG] || !cda[CTA_TUPLE_REPLY])
2447 				return -EINVAL;
2448 			if (otuple.dst.protonum != rtuple.dst.protonum)
2449 				return -EINVAL;
2450 
2451 			ct = ctnetlink_create_conntrack(info->net, &zone, cda,
2452 							&otuple, &rtuple, u3);
2453 			if (IS_ERR(ct))
2454 				return PTR_ERR(ct);
2455 
2456 			err = 0;
2457 			if (test_bit(IPS_EXPECTED_BIT, &ct->status))
2458 				events = 1 << IPCT_RELATED;
2459 			else
2460 				events = 1 << IPCT_NEW;
2461 
2462 			if (cda[CTA_LABELS] &&
2463 			    ctnetlink_attach_labels(ct, cda) == 0)
2464 				events |= (1 << IPCT_LABEL);
2465 
2466 			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
2467 						      (1 << IPCT_ASSURED) |
2468 						      (1 << IPCT_HELPER) |
2469 						      (1 << IPCT_PROTOINFO) |
2470 						      (1 << IPCT_SEQADJ) |
2471 						      (1 << IPCT_MARK) |
2472 						      (1 << IPCT_SYNPROXY) |
2473 						      events,
2474 						      ct, NETLINK_CB(skb).portid,
2475 						      nlmsg_report(info->nlh));
2476 			nf_ct_put(ct);
2477 		}
2478 
2479 		return err;
2480 	}
2481 	/* implicit 'else' */
2482 
2483 	err = -EEXIST;
2484 	ct = nf_ct_tuplehash_to_ctrack(h);
2485 	if (!(info->nlh->nlmsg_flags & NLM_F_EXCL)) {
2486 		err = ctnetlink_change_conntrack(ct, cda);
2487 		if (err == 0) {
2488 			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
2489 						      (1 << IPCT_ASSURED) |
2490 						      (1 << IPCT_HELPER) |
2491 						      (1 << IPCT_LABEL) |
2492 						      (1 << IPCT_PROTOINFO) |
2493 						      (1 << IPCT_SEQADJ) |
2494 						      (1 << IPCT_MARK) |
2495 						      (1 << IPCT_SYNPROXY),
2496 						      ct, NETLINK_CB(skb).portid,
2497 						      nlmsg_report(info->nlh));
2498 		}
2499 	}
2500 
2501 	nf_ct_put(ct);
2502 	return err;
2503 }
2504 
2505 static int
ctnetlink_ct_stat_cpu_fill_info(struct sk_buff * skb,u32 portid,u32 seq,__u16 cpu,const struct ip_conntrack_stat * st)2506 ctnetlink_ct_stat_cpu_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
2507 				__u16 cpu, const struct ip_conntrack_stat *st)
2508 {
2509 	struct nlmsghdr *nlh;
2510 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
2511 
2512 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK,
2513 			      IPCTNL_MSG_CT_GET_STATS_CPU);
2514 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
2515 			   NFNETLINK_V0, htons(cpu));
2516 	if (!nlh)
2517 		goto nlmsg_failure;
2518 
2519 	if (nla_put_be32(skb, CTA_STATS_FOUND, htonl(st->found)) ||
2520 	    nla_put_be32(skb, CTA_STATS_INVALID, htonl(st->invalid)) ||
2521 	    nla_put_be32(skb, CTA_STATS_INSERT, htonl(st->insert)) ||
2522 	    nla_put_be32(skb, CTA_STATS_INSERT_FAILED,
2523 				htonl(st->insert_failed)) ||
2524 	    nla_put_be32(skb, CTA_STATS_DROP, htonl(st->drop)) ||
2525 	    nla_put_be32(skb, CTA_STATS_EARLY_DROP, htonl(st->early_drop)) ||
2526 	    nla_put_be32(skb, CTA_STATS_ERROR, htonl(st->error)) ||
2527 	    nla_put_be32(skb, CTA_STATS_SEARCH_RESTART,
2528 				htonl(st->search_restart)) ||
2529 	    nla_put_be32(skb, CTA_STATS_CLASH_RESOLVE,
2530 				htonl(st->clash_resolve)) ||
2531 	    nla_put_be32(skb, CTA_STATS_CHAIN_TOOLONG,
2532 			 htonl(st->chaintoolong)))
2533 		goto nla_put_failure;
2534 
2535 	nlmsg_end(skb, nlh);
2536 	return skb->len;
2537 
2538 nla_put_failure:
2539 nlmsg_failure:
2540 	nlmsg_cancel(skb, nlh);
2541 	return -1;
2542 }
2543 
2544 static int
ctnetlink_ct_stat_cpu_dump(struct sk_buff * skb,struct netlink_callback * cb)2545 ctnetlink_ct_stat_cpu_dump(struct sk_buff *skb, struct netlink_callback *cb)
2546 {
2547 	int cpu;
2548 	struct net *net = sock_net(skb->sk);
2549 
2550 	if (cb->args[0] == nr_cpu_ids)
2551 		return 0;
2552 
2553 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
2554 		const struct ip_conntrack_stat *st;
2555 
2556 		if (!cpu_possible(cpu))
2557 			continue;
2558 
2559 		st = per_cpu_ptr(net->ct.stat, cpu);
2560 		if (ctnetlink_ct_stat_cpu_fill_info(skb,
2561 						    NETLINK_CB(cb->skb).portid,
2562 						    cb->nlh->nlmsg_seq,
2563 						    cpu, st) < 0)
2564 				break;
2565 	}
2566 	cb->args[0] = cpu;
2567 
2568 	return skb->len;
2569 }
2570 
ctnetlink_stat_ct_cpu(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2571 static int ctnetlink_stat_ct_cpu(struct sk_buff *skb,
2572 				 const struct nfnl_info *info,
2573 				 const struct nlattr * const cda[])
2574 {
2575 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
2576 		struct netlink_dump_control c = {
2577 			.dump = ctnetlink_ct_stat_cpu_dump,
2578 		};
2579 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
2580 	}
2581 
2582 	return 0;
2583 }
2584 
2585 static int
ctnetlink_stat_ct_fill_info(struct sk_buff * skb,u32 portid,u32 seq,u32 type,struct net * net)2586 ctnetlink_stat_ct_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
2587 			    struct net *net)
2588 {
2589 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
2590 	unsigned int nr_conntracks;
2591 	struct nlmsghdr *nlh;
2592 
2593 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_GET_STATS);
2594 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
2595 			   NFNETLINK_V0, 0);
2596 	if (!nlh)
2597 		goto nlmsg_failure;
2598 
2599 	nr_conntracks = nf_conntrack_count(net);
2600 	if (nla_put_be32(skb, CTA_STATS_GLOBAL_ENTRIES, htonl(nr_conntracks)))
2601 		goto nla_put_failure;
2602 
2603 	if (nla_put_be32(skb, CTA_STATS_GLOBAL_MAX_ENTRIES, htonl(nf_conntrack_max)))
2604 		goto nla_put_failure;
2605 
2606 	nlmsg_end(skb, nlh);
2607 	return skb->len;
2608 
2609 nla_put_failure:
2610 nlmsg_failure:
2611 	nlmsg_cancel(skb, nlh);
2612 	return -1;
2613 }
2614 
ctnetlink_stat_ct(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2615 static int ctnetlink_stat_ct(struct sk_buff *skb, const struct nfnl_info *info,
2616 			     const struct nlattr * const cda[])
2617 {
2618 	struct sk_buff *skb2;
2619 	int err;
2620 
2621 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
2622 	if (skb2 == NULL)
2623 		return -ENOMEM;
2624 
2625 	err = ctnetlink_stat_ct_fill_info(skb2, NETLINK_CB(skb).portid,
2626 					  info->nlh->nlmsg_seq,
2627 					  NFNL_MSG_TYPE(info->nlh->nlmsg_type),
2628 					  sock_net(skb->sk));
2629 	if (err <= 0) {
2630 		kfree_skb(skb2);
2631 		return -ENOMEM;
2632 	}
2633 
2634 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
2635 }
2636 
2637 static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
2638 	[CTA_EXPECT_MASTER]	= { .type = NLA_NESTED },
2639 	[CTA_EXPECT_TUPLE]	= { .type = NLA_NESTED },
2640 	[CTA_EXPECT_MASK]	= { .type = NLA_NESTED },
2641 	[CTA_EXPECT_TIMEOUT]	= { .type = NLA_U32 },
2642 	[CTA_EXPECT_ID]		= { .type = NLA_U32 },
2643 	[CTA_EXPECT_HELP_NAME]	= { .type = NLA_NUL_STRING,
2644 				    .len = NF_CT_HELPER_NAME_LEN - 1 },
2645 	[CTA_EXPECT_ZONE]	= { .type = NLA_U16 },
2646 	[CTA_EXPECT_FLAGS]	= { .type = NLA_U32 },
2647 	[CTA_EXPECT_CLASS]	= { .type = NLA_U32 },
2648 	[CTA_EXPECT_NAT]	= { .type = NLA_NESTED },
2649 	[CTA_EXPECT_FN]		= { .type = NLA_NUL_STRING },
2650 };
2651 
2652 static struct nf_conntrack_expect *
2653 ctnetlink_alloc_expect(const struct nlattr *const cda[], struct nf_conn *ct,
2654 		       struct nf_conntrack_helper *helper,
2655 		       struct nf_conntrack_tuple *tuple,
2656 		       struct nf_conntrack_tuple *mask);
2657 
2658 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
2659 static size_t
ctnetlink_glue_build_size(const struct nf_conn * ct)2660 ctnetlink_glue_build_size(const struct nf_conn *ct)
2661 {
2662 	return 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
2663 	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
2664 	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
2665 	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
2666 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
2667 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
2668 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
2669 	       + nla_total_size(0) /* CTA_PROTOINFO */
2670 	       + nla_total_size(0) /* CTA_HELP */
2671 	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
2672 	       + ctnetlink_secctx_size(ct)
2673 	       + ctnetlink_acct_size(ct)
2674 	       + ctnetlink_timestamp_size(ct)
2675 #if IS_ENABLED(CONFIG_NF_NAT)
2676 	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
2677 	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
2678 #endif
2679 #ifdef CONFIG_NF_CONNTRACK_MARK
2680 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
2681 #endif
2682 #ifdef CONFIG_NF_CONNTRACK_ZONES
2683 	       + nla_total_size(sizeof(u_int16_t)) /* CTA_ZONE|CTA_TUPLE_ZONE */
2684 #endif
2685 	       + ctnetlink_proto_size(ct)
2686 	       ;
2687 }
2688 
__ctnetlink_glue_build(struct sk_buff * skb,struct nf_conn * ct)2689 static int __ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct)
2690 {
2691 	const struct nf_conntrack_zone *zone;
2692 	struct nlattr *nest_parms;
2693 
2694 	zone = nf_ct_zone(ct);
2695 
2696 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
2697 	if (!nest_parms)
2698 		goto nla_put_failure;
2699 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
2700 		goto nla_put_failure;
2701 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
2702 				   NF_CT_ZONE_DIR_ORIG) < 0)
2703 		goto nla_put_failure;
2704 	nla_nest_end(skb, nest_parms);
2705 
2706 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
2707 	if (!nest_parms)
2708 		goto nla_put_failure;
2709 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
2710 		goto nla_put_failure;
2711 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
2712 				   NF_CT_ZONE_DIR_REPL) < 0)
2713 		goto nla_put_failure;
2714 	nla_nest_end(skb, nest_parms);
2715 
2716 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
2717 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
2718 		goto nla_put_failure;
2719 
2720 	if (ctnetlink_dump_id(skb, ct) < 0)
2721 		goto nla_put_failure;
2722 
2723 	if (ctnetlink_dump_status(skb, ct) < 0)
2724 		goto nla_put_failure;
2725 
2726 	if (ctnetlink_dump_timeout(skb, ct, false) < 0)
2727 		goto nla_put_failure;
2728 
2729 	if (ctnetlink_dump_protoinfo(skb, ct, false) < 0)
2730 		goto nla_put_failure;
2731 
2732 	if (ctnetlink_dump_acct(skb, ct, IPCTNL_MSG_CT_GET) < 0 ||
2733 	    ctnetlink_dump_timestamp(skb, ct) < 0)
2734 		goto nla_put_failure;
2735 
2736 	if (ctnetlink_dump_helpinfo(skb, ct) < 0)
2737 		goto nla_put_failure;
2738 
2739 #ifdef CONFIG_NF_CONNTRACK_SECMARK
2740 	if (ct->secmark && ctnetlink_dump_secctx(skb, ct) < 0)
2741 		goto nla_put_failure;
2742 #endif
2743 	if (ct->master && ctnetlink_dump_master(skb, ct) < 0)
2744 		goto nla_put_failure;
2745 
2746 	if ((ct->status & IPS_SEQ_ADJUST) &&
2747 	    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
2748 		goto nla_put_failure;
2749 
2750 	if (ctnetlink_dump_ct_synproxy(skb, ct) < 0)
2751 		goto nla_put_failure;
2752 
2753 #ifdef CONFIG_NF_CONNTRACK_MARK
2754 	if (ctnetlink_dump_mark(skb, ct, true) < 0)
2755 		goto nla_put_failure;
2756 #endif
2757 	if (ctnetlink_dump_labels(skb, ct) < 0)
2758 		goto nla_put_failure;
2759 	return 0;
2760 
2761 nla_put_failure:
2762 	return -ENOSPC;
2763 }
2764 
2765 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)2766 ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct,
2767 		     enum ip_conntrack_info ctinfo,
2768 		     u_int16_t ct_attr, u_int16_t ct_info_attr)
2769 {
2770 	struct nlattr *nest_parms;
2771 
2772 	nest_parms = nla_nest_start(skb, ct_attr);
2773 	if (!nest_parms)
2774 		goto nla_put_failure;
2775 
2776 	if (__ctnetlink_glue_build(skb, ct) < 0)
2777 		goto nla_put_failure;
2778 
2779 	nla_nest_end(skb, nest_parms);
2780 
2781 	if (nla_put_be32(skb, ct_info_attr, htonl(ctinfo)))
2782 		goto nla_put_failure;
2783 
2784 	return 0;
2785 
2786 nla_put_failure:
2787 	return -ENOSPC;
2788 }
2789 
2790 static int
ctnetlink_update_status(struct nf_conn * ct,const struct nlattr * const cda[])2791 ctnetlink_update_status(struct nf_conn *ct, const struct nlattr * const cda[])
2792 {
2793 	unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
2794 	unsigned long d = ct->status ^ status;
2795 
2796 	if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
2797 		/* SEEN_REPLY bit can only be set */
2798 		return -EBUSY;
2799 
2800 	if (d & IPS_ASSURED && !(status & IPS_ASSURED))
2801 		/* ASSURED bit can only be set */
2802 		return -EBUSY;
2803 
2804 	/* This check is less strict than ctnetlink_change_status()
2805 	 * because callers often flip IPS_EXPECTED bits when sending
2806 	 * an NFQA_CT attribute to the kernel.  So ignore the
2807 	 * unchangeable bits but do not error out. Also user programs
2808 	 * are allowed to clear the bits that they are allowed to change.
2809 	 */
2810 	__ctnetlink_change_status(ct, status, ~status);
2811 	return 0;
2812 }
2813 
2814 static int
ctnetlink_glue_parse_ct(const struct nlattr * cda[],struct nf_conn * ct)2815 ctnetlink_glue_parse_ct(const struct nlattr *cda[], struct nf_conn *ct)
2816 {
2817 	int err;
2818 
2819 	if (cda[CTA_TIMEOUT]) {
2820 		err = ctnetlink_change_timeout(ct, cda);
2821 		if (err < 0)
2822 			return err;
2823 	}
2824 	if (cda[CTA_STATUS]) {
2825 		err = ctnetlink_update_status(ct, cda);
2826 		if (err < 0)
2827 			return err;
2828 	}
2829 	if (cda[CTA_HELP]) {
2830 		err = ctnetlink_change_helper(ct, cda);
2831 		if (err < 0)
2832 			return err;
2833 	}
2834 	if (cda[CTA_LABELS]) {
2835 		err = ctnetlink_attach_labels(ct, cda);
2836 		if (err < 0)
2837 			return err;
2838 	}
2839 #if defined(CONFIG_NF_CONNTRACK_MARK)
2840 	if (cda[CTA_MARK]) {
2841 		ctnetlink_change_mark(ct, cda);
2842 	}
2843 #endif
2844 	return 0;
2845 }
2846 
2847 static int
ctnetlink_glue_parse(const struct nlattr * attr,struct nf_conn * ct)2848 ctnetlink_glue_parse(const struct nlattr *attr, struct nf_conn *ct)
2849 {
2850 	struct nlattr *cda[CTA_MAX+1];
2851 	int ret;
2852 
2853 	ret = nla_parse_nested_deprecated(cda, CTA_MAX, attr, ct_nla_policy,
2854 					  NULL);
2855 	if (ret < 0)
2856 		return ret;
2857 
2858 	return ctnetlink_glue_parse_ct((const struct nlattr **)cda, ct);
2859 }
2860 
ctnetlink_glue_exp_parse(const struct nlattr * const * cda,const struct nf_conn * ct,struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple * mask)2861 static int ctnetlink_glue_exp_parse(const struct nlattr * const *cda,
2862 				    const struct nf_conn *ct,
2863 				    struct nf_conntrack_tuple *tuple,
2864 				    struct nf_conntrack_tuple *mask)
2865 {
2866 	int err;
2867 
2868 	err = ctnetlink_parse_tuple(cda, tuple, CTA_EXPECT_TUPLE,
2869 				    nf_ct_l3num(ct), NULL);
2870 	if (err < 0)
2871 		return err;
2872 
2873 	return ctnetlink_parse_tuple(cda, mask, CTA_EXPECT_MASK,
2874 				     nf_ct_l3num(ct), NULL);
2875 }
2876 
2877 static int
ctnetlink_glue_attach_expect(const struct nlattr * attr,struct nf_conn * ct,u32 portid,u32 report)2878 ctnetlink_glue_attach_expect(const struct nlattr *attr, struct nf_conn *ct,
2879 			     u32 portid, u32 report)
2880 {
2881 	struct nlattr *cda[CTA_EXPECT_MAX+1];
2882 	struct nf_conntrack_tuple tuple, mask;
2883 	struct nf_conntrack_helper *helper = NULL;
2884 	struct nf_conntrack_expect *exp;
2885 	int err;
2886 
2887 	err = nla_parse_nested_deprecated(cda, CTA_EXPECT_MAX, attr,
2888 					  exp_nla_policy, NULL);
2889 	if (err < 0)
2890 		return err;
2891 
2892 	err = ctnetlink_glue_exp_parse((const struct nlattr * const *)cda,
2893 				       ct, &tuple, &mask);
2894 	if (err < 0)
2895 		return err;
2896 
2897 	if (cda[CTA_EXPECT_HELP_NAME]) {
2898 		const char *helpname = nla_data(cda[CTA_EXPECT_HELP_NAME]);
2899 
2900 		helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
2901 						    nf_ct_protonum(ct));
2902 		if (helper == NULL)
2903 			return -EOPNOTSUPP;
2904 	}
2905 
2906 	exp = ctnetlink_alloc_expect((const struct nlattr * const *)cda, ct,
2907 				     helper, &tuple, &mask);
2908 	if (IS_ERR(exp))
2909 		return PTR_ERR(exp);
2910 
2911 	err = nf_ct_expect_related_report(exp, portid, report, 0);
2912 	nf_ct_expect_put(exp);
2913 	return err;
2914 }
2915 
ctnetlink_glue_seqadj(struct sk_buff * skb,struct nf_conn * ct,enum ip_conntrack_info ctinfo,int diff)2916 static void ctnetlink_glue_seqadj(struct sk_buff *skb, struct nf_conn *ct,
2917 				  enum ip_conntrack_info ctinfo, int diff)
2918 {
2919 	if (!(ct->status & IPS_NAT_MASK))
2920 		return;
2921 
2922 	nf_ct_tcp_seqadj_set(skb, ct, ctinfo, diff);
2923 }
2924 
2925 static struct nfnl_ct_hook ctnetlink_glue_hook = {
2926 	.build_size	= ctnetlink_glue_build_size,
2927 	.build		= ctnetlink_glue_build,
2928 	.parse		= ctnetlink_glue_parse,
2929 	.attach_expect	= ctnetlink_glue_attach_expect,
2930 	.seq_adjust	= ctnetlink_glue_seqadj,
2931 };
2932 #endif /* CONFIG_NETFILTER_NETLINK_GLUE_CT */
2933 
2934 /***********************************************************************
2935  * EXPECT
2936  ***********************************************************************/
2937 
ctnetlink_exp_dump_tuple(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,u32 type)2938 static int ctnetlink_exp_dump_tuple(struct sk_buff *skb,
2939 				    const struct nf_conntrack_tuple *tuple,
2940 				    u32 type)
2941 {
2942 	struct nlattr *nest_parms;
2943 
2944 	nest_parms = nla_nest_start(skb, type);
2945 	if (!nest_parms)
2946 		goto nla_put_failure;
2947 	if (ctnetlink_dump_tuples(skb, tuple) < 0)
2948 		goto nla_put_failure;
2949 	nla_nest_end(skb, nest_parms);
2950 
2951 	return 0;
2952 
2953 nla_put_failure:
2954 	return -1;
2955 }
2956 
ctnetlink_exp_dump_mask(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_tuple_mask * mask)2957 static int ctnetlink_exp_dump_mask(struct sk_buff *skb,
2958 				   const struct nf_conntrack_tuple *tuple,
2959 				   const struct nf_conntrack_tuple_mask *mask)
2960 {
2961 	const struct nf_conntrack_l4proto *l4proto;
2962 	struct nf_conntrack_tuple m;
2963 	struct nlattr *nest_parms;
2964 	int ret;
2965 
2966 	memset(&m, 0xFF, sizeof(m));
2967 	memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
2968 	m.src.u.all = mask->src.u.all;
2969 	m.src.l3num = tuple->src.l3num;
2970 	m.dst.protonum = tuple->dst.protonum;
2971 
2972 	nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK);
2973 	if (!nest_parms)
2974 		goto nla_put_failure;
2975 
2976 	rcu_read_lock();
2977 	ret = ctnetlink_dump_tuples_ip(skb, &m);
2978 	if (ret >= 0) {
2979 		l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
2980 		ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
2981 	}
2982 	rcu_read_unlock();
2983 
2984 	if (unlikely(ret < 0))
2985 		goto nla_put_failure;
2986 
2987 	nla_nest_end(skb, nest_parms);
2988 
2989 	return 0;
2990 
2991 nla_put_failure:
2992 	return -1;
2993 }
2994 
2995 #if IS_ENABLED(CONFIG_NF_NAT)
2996 static const union nf_inet_addr any_addr;
2997 #endif
2998 
nf_expect_get_id(const struct nf_conntrack_expect * exp)2999 static __be32 nf_expect_get_id(const struct nf_conntrack_expect *exp)
3000 {
3001 	static __read_mostly siphash_key_t exp_id_seed;
3002 	unsigned long a, b, c, d;
3003 
3004 	net_get_random_once(&exp_id_seed, sizeof(exp_id_seed));
3005 
3006 	a = (unsigned long)exp;
3007 	b = (unsigned long)exp->helper;
3008 	c = (unsigned long)exp->master;
3009 	d = (unsigned long)siphash(&exp->tuple, sizeof(exp->tuple), &exp_id_seed);
3010 
3011 #ifdef CONFIG_64BIT
3012 	return (__force __be32)siphash_4u64((u64)a, (u64)b, (u64)c, (u64)d, &exp_id_seed);
3013 #else
3014 	return (__force __be32)siphash_4u32((u32)a, (u32)b, (u32)c, (u32)d, &exp_id_seed);
3015 #endif
3016 }
3017 
3018 static int
ctnetlink_exp_dump_expect(struct sk_buff * skb,const struct nf_conntrack_expect * exp)3019 ctnetlink_exp_dump_expect(struct sk_buff *skb,
3020 			  const struct nf_conntrack_expect *exp)
3021 {
3022 	struct nf_conn *master = exp->master;
3023 	long timeout = ((long)exp->timeout.expires - (long)jiffies) / HZ;
3024 	struct nf_conn_help *help;
3025 #if IS_ENABLED(CONFIG_NF_NAT)
3026 	struct nlattr *nest_parms;
3027 	struct nf_conntrack_tuple nat_tuple = {};
3028 #endif
3029 	struct nf_ct_helper_expectfn *expfn;
3030 
3031 	if (timeout < 0)
3032 		timeout = 0;
3033 
3034 	if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
3035 		goto nla_put_failure;
3036 	if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
3037 		goto nla_put_failure;
3038 	if (ctnetlink_exp_dump_tuple(skb,
3039 				 &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
3040 				 CTA_EXPECT_MASTER) < 0)
3041 		goto nla_put_failure;
3042 
3043 #if IS_ENABLED(CONFIG_NF_NAT)
3044 	if (!nf_inet_addr_cmp(&exp->saved_addr, &any_addr) ||
3045 	    exp->saved_proto.all) {
3046 		nest_parms = nla_nest_start(skb, CTA_EXPECT_NAT);
3047 		if (!nest_parms)
3048 			goto nla_put_failure;
3049 
3050 		if (nla_put_be32(skb, CTA_EXPECT_NAT_DIR, htonl(exp->dir)))
3051 			goto nla_put_failure;
3052 
3053 		nat_tuple.src.l3num = nf_ct_l3num(master);
3054 		nat_tuple.src.u3 = exp->saved_addr;
3055 		nat_tuple.dst.protonum = nf_ct_protonum(master);
3056 		nat_tuple.src.u = exp->saved_proto;
3057 
3058 		if (ctnetlink_exp_dump_tuple(skb, &nat_tuple,
3059 						CTA_EXPECT_NAT_TUPLE) < 0)
3060 	                goto nla_put_failure;
3061 	        nla_nest_end(skb, nest_parms);
3062 	}
3063 #endif
3064 	if (nla_put_be32(skb, CTA_EXPECT_TIMEOUT, htonl(timeout)) ||
3065 	    nla_put_be32(skb, CTA_EXPECT_ID, nf_expect_get_id(exp)) ||
3066 	    nla_put_be32(skb, CTA_EXPECT_FLAGS, htonl(exp->flags)) ||
3067 	    nla_put_be32(skb, CTA_EXPECT_CLASS, htonl(exp->class)))
3068 		goto nla_put_failure;
3069 	help = nfct_help(master);
3070 	if (help) {
3071 		struct nf_conntrack_helper *helper;
3072 
3073 		helper = rcu_dereference(help->helper);
3074 		if (helper &&
3075 		    nla_put_string(skb, CTA_EXPECT_HELP_NAME, helper->name))
3076 			goto nla_put_failure;
3077 	}
3078 	expfn = nf_ct_helper_expectfn_find_by_symbol(exp->expectfn);
3079 	if (expfn != NULL &&
3080 	    nla_put_string(skb, CTA_EXPECT_FN, expfn->name))
3081 		goto nla_put_failure;
3082 
3083 	return 0;
3084 
3085 nla_put_failure:
3086 	return -1;
3087 }
3088 
3089 static int
ctnetlink_exp_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int event,const struct nf_conntrack_expect * exp)3090 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
3091 			int event, const struct nf_conntrack_expect *exp)
3092 {
3093 	struct nlmsghdr *nlh;
3094 	unsigned int flags = portid ? NLM_F_MULTI : 0;
3095 
3096 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK_EXP, event);
3097 	nlh = nfnl_msg_put(skb, portid, seq, event, flags,
3098 			   exp->tuple.src.l3num, NFNETLINK_V0, 0);
3099 	if (!nlh)
3100 		goto nlmsg_failure;
3101 
3102 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
3103 		goto nla_put_failure;
3104 
3105 	nlmsg_end(skb, nlh);
3106 	return skb->len;
3107 
3108 nlmsg_failure:
3109 nla_put_failure:
3110 	nlmsg_cancel(skb, nlh);
3111 	return -1;
3112 }
3113 
3114 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3115 static int
ctnetlink_expect_event(unsigned int events,const struct nf_exp_event * item)3116 ctnetlink_expect_event(unsigned int events, const struct nf_exp_event *item)
3117 {
3118 	struct nf_conntrack_expect *exp = item->exp;
3119 	struct net *net = nf_ct_exp_net(exp);
3120 	struct nlmsghdr *nlh;
3121 	struct sk_buff *skb;
3122 	unsigned int type, group;
3123 	int flags = 0;
3124 
3125 	if (events & (1 << IPEXP_DESTROY)) {
3126 		type = IPCTNL_MSG_EXP_DELETE;
3127 		group = NFNLGRP_CONNTRACK_EXP_DESTROY;
3128 	} else if (events & (1 << IPEXP_NEW)) {
3129 		type = IPCTNL_MSG_EXP_NEW;
3130 		flags = NLM_F_CREATE|NLM_F_EXCL;
3131 		group = NFNLGRP_CONNTRACK_EXP_NEW;
3132 	} else
3133 		return 0;
3134 
3135 	if (!item->report && !nfnetlink_has_listeners(net, group))
3136 		return 0;
3137 
3138 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
3139 	if (skb == NULL)
3140 		goto errout;
3141 
3142 	type = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK_EXP, type);
3143 	nlh = nfnl_msg_put(skb, item->portid, 0, type, flags,
3144 			   exp->tuple.src.l3num, NFNETLINK_V0, 0);
3145 	if (!nlh)
3146 		goto nlmsg_failure;
3147 
3148 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
3149 		goto nla_put_failure;
3150 
3151 	nlmsg_end(skb, nlh);
3152 	nfnetlink_send(skb, net, item->portid, group, item->report, GFP_ATOMIC);
3153 	return 0;
3154 
3155 nla_put_failure:
3156 	nlmsg_cancel(skb, nlh);
3157 nlmsg_failure:
3158 	kfree_skb(skb);
3159 errout:
3160 	nfnetlink_set_err(net, 0, 0, -ENOBUFS);
3161 	return 0;
3162 }
3163 #endif
ctnetlink_exp_done(struct netlink_callback * cb)3164 static int ctnetlink_exp_done(struct netlink_callback *cb)
3165 {
3166 	if (cb->args[1])
3167 		nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
3168 	return 0;
3169 }
3170 
3171 static int
ctnetlink_exp_dump_table(struct sk_buff * skb,struct netlink_callback * cb)3172 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
3173 {
3174 	struct net *net = sock_net(skb->sk);
3175 	struct nf_conntrack_expect *exp, *last;
3176 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
3177 	u_int8_t l3proto = nfmsg->nfgen_family;
3178 
3179 	rcu_read_lock();
3180 	last = (struct nf_conntrack_expect *)cb->args[1];
3181 	for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
3182 restart:
3183 		hlist_for_each_entry_rcu(exp, &nf_ct_expect_hash[cb->args[0]],
3184 					 hnode) {
3185 			if (l3proto && exp->tuple.src.l3num != l3proto)
3186 				continue;
3187 
3188 			if (!net_eq(nf_ct_net(exp->master), net))
3189 				continue;
3190 
3191 			if (cb->args[1]) {
3192 				if (exp != last)
3193 					continue;
3194 				cb->args[1] = 0;
3195 			}
3196 			if (ctnetlink_exp_fill_info(skb,
3197 						    NETLINK_CB(cb->skb).portid,
3198 						    cb->nlh->nlmsg_seq,
3199 						    IPCTNL_MSG_EXP_NEW,
3200 						    exp) < 0) {
3201 				if (!refcount_inc_not_zero(&exp->use))
3202 					continue;
3203 				cb->args[1] = (unsigned long)exp;
3204 				goto out;
3205 			}
3206 		}
3207 		if (cb->args[1]) {
3208 			cb->args[1] = 0;
3209 			goto restart;
3210 		}
3211 	}
3212 out:
3213 	rcu_read_unlock();
3214 	if (last)
3215 		nf_ct_expect_put(last);
3216 
3217 	return skb->len;
3218 }
3219 
3220 static int
ctnetlink_exp_ct_dump_table(struct sk_buff * skb,struct netlink_callback * cb)3221 ctnetlink_exp_ct_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
3222 {
3223 	struct nf_conntrack_expect *exp, *last;
3224 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
3225 	struct nf_conn *ct = cb->data;
3226 	struct nf_conn_help *help = nfct_help(ct);
3227 	u_int8_t l3proto = nfmsg->nfgen_family;
3228 
3229 	if (cb->args[0])
3230 		return 0;
3231 
3232 	rcu_read_lock();
3233 	last = (struct nf_conntrack_expect *)cb->args[1];
3234 restart:
3235 	hlist_for_each_entry_rcu(exp, &help->expectations, lnode) {
3236 		if (l3proto && exp->tuple.src.l3num != l3proto)
3237 			continue;
3238 		if (cb->args[1]) {
3239 			if (exp != last)
3240 				continue;
3241 			cb->args[1] = 0;
3242 		}
3243 		if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).portid,
3244 					    cb->nlh->nlmsg_seq,
3245 					    IPCTNL_MSG_EXP_NEW,
3246 					    exp) < 0) {
3247 			if (!refcount_inc_not_zero(&exp->use))
3248 				continue;
3249 			cb->args[1] = (unsigned long)exp;
3250 			goto out;
3251 		}
3252 	}
3253 	if (cb->args[1]) {
3254 		cb->args[1] = 0;
3255 		goto restart;
3256 	}
3257 	cb->args[0] = 1;
3258 out:
3259 	rcu_read_unlock();
3260 	if (last)
3261 		nf_ct_expect_put(last);
3262 
3263 	return skb->len;
3264 }
3265 
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)3266 static int ctnetlink_dump_exp_ct(struct net *net, struct sock *ctnl,
3267 				 struct sk_buff *skb,
3268 				 const struct nlmsghdr *nlh,
3269 				 const struct nlattr * const cda[],
3270 				 struct netlink_ext_ack *extack)
3271 {
3272 	int err;
3273 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3274 	u_int8_t u3 = nfmsg->nfgen_family;
3275 	struct nf_conntrack_tuple tuple;
3276 	struct nf_conntrack_tuple_hash *h;
3277 	struct nf_conn *ct;
3278 	struct nf_conntrack_zone zone;
3279 	struct netlink_dump_control c = {
3280 		.dump = ctnetlink_exp_ct_dump_table,
3281 		.done = ctnetlink_exp_done,
3282 	};
3283 
3284 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER,
3285 				    u3, NULL);
3286 	if (err < 0)
3287 		return err;
3288 
3289 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3290 	if (err < 0)
3291 		return err;
3292 
3293 	h = nf_conntrack_find_get(net, &zone, &tuple);
3294 	if (!h)
3295 		return -ENOENT;
3296 
3297 	ct = nf_ct_tuplehash_to_ctrack(h);
3298 	/* No expectation linked to this connection tracking. */
3299 	if (!nfct_help(ct)) {
3300 		nf_ct_put(ct);
3301 		return 0;
3302 	}
3303 
3304 	c.data = ct;
3305 
3306 	err = netlink_dump_start(ctnl, skb, nlh, &c);
3307 	nf_ct_put(ct);
3308 
3309 	return err;
3310 }
3311 
ctnetlink_get_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3312 static int ctnetlink_get_expect(struct sk_buff *skb,
3313 				const struct nfnl_info *info,
3314 				const struct nlattr * const cda[])
3315 {
3316 	u_int8_t u3 = info->nfmsg->nfgen_family;
3317 	struct nf_conntrack_tuple tuple;
3318 	struct nf_conntrack_expect *exp;
3319 	struct nf_conntrack_zone zone;
3320 	struct sk_buff *skb2;
3321 	int err;
3322 
3323 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
3324 		if (cda[CTA_EXPECT_MASTER])
3325 			return ctnetlink_dump_exp_ct(info->net, info->sk, skb,
3326 						     info->nlh, cda,
3327 						     info->extack);
3328 		else {
3329 			struct netlink_dump_control c = {
3330 				.dump = ctnetlink_exp_dump_table,
3331 				.done = ctnetlink_exp_done,
3332 			};
3333 			return netlink_dump_start(info->sk, skb, info->nlh, &c);
3334 		}
3335 	}
3336 
3337 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3338 	if (err < 0)
3339 		return err;
3340 
3341 	if (cda[CTA_EXPECT_TUPLE])
3342 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3343 					    u3, NULL);
3344 	else if (cda[CTA_EXPECT_MASTER])
3345 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER,
3346 					    u3, NULL);
3347 	else
3348 		return -EINVAL;
3349 
3350 	if (err < 0)
3351 		return err;
3352 
3353 	exp = nf_ct_expect_find_get(info->net, &zone, &tuple);
3354 	if (!exp)
3355 		return -ENOENT;
3356 
3357 	if (cda[CTA_EXPECT_ID]) {
3358 		__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
3359 
3360 		if (id != nf_expect_get_id(exp)) {
3361 			nf_ct_expect_put(exp);
3362 			return -ENOENT;
3363 		}
3364 	}
3365 
3366 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
3367 	if (!skb2) {
3368 		nf_ct_expect_put(exp);
3369 		return -ENOMEM;
3370 	}
3371 
3372 	rcu_read_lock();
3373 	err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).portid,
3374 				      info->nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
3375 				      exp);
3376 	rcu_read_unlock();
3377 	nf_ct_expect_put(exp);
3378 	if (err <= 0) {
3379 		kfree_skb(skb2);
3380 		return -ENOMEM;
3381 	}
3382 
3383 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
3384 }
3385 
expect_iter_name(struct nf_conntrack_expect * exp,void * data)3386 static bool expect_iter_name(struct nf_conntrack_expect *exp, void *data)
3387 {
3388 	const struct nf_conn_help *m_help;
3389 	const char *name = data;
3390 
3391 	m_help = nfct_help(exp->master);
3392 
3393 	return strcmp(m_help->helper->name, name) == 0;
3394 }
3395 
expect_iter_all(struct nf_conntrack_expect * exp,void * data)3396 static bool expect_iter_all(struct nf_conntrack_expect *exp, void *data)
3397 {
3398 	return true;
3399 }
3400 
ctnetlink_del_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3401 static int ctnetlink_del_expect(struct sk_buff *skb,
3402 				const struct nfnl_info *info,
3403 				const struct nlattr * const cda[])
3404 {
3405 	u_int8_t u3 = info->nfmsg->nfgen_family;
3406 	struct nf_conntrack_expect *exp;
3407 	struct nf_conntrack_tuple tuple;
3408 	struct nf_conntrack_zone zone;
3409 	int err;
3410 
3411 	if (cda[CTA_EXPECT_TUPLE]) {
3412 		/* delete a single expect by tuple */
3413 		err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3414 		if (err < 0)
3415 			return err;
3416 
3417 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3418 					    u3, NULL);
3419 		if (err < 0)
3420 			return err;
3421 
3422 		/* bump usage count to 2 */
3423 		exp = nf_ct_expect_find_get(info->net, &zone, &tuple);
3424 		if (!exp)
3425 			return -ENOENT;
3426 
3427 		if (cda[CTA_EXPECT_ID]) {
3428 			__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
3429 			if (ntohl(id) != (u32)(unsigned long)exp) {
3430 				nf_ct_expect_put(exp);
3431 				return -ENOENT;
3432 			}
3433 		}
3434 
3435 		/* after list removal, usage count == 1 */
3436 		spin_lock_bh(&nf_conntrack_expect_lock);
3437 		if (del_timer(&exp->timeout)) {
3438 			nf_ct_unlink_expect_report(exp, NETLINK_CB(skb).portid,
3439 						   nlmsg_report(info->nlh));
3440 			nf_ct_expect_put(exp);
3441 		}
3442 		spin_unlock_bh(&nf_conntrack_expect_lock);
3443 		/* have to put what we 'get' above.
3444 		 * after this line usage count == 0 */
3445 		nf_ct_expect_put(exp);
3446 	} else if (cda[CTA_EXPECT_HELP_NAME]) {
3447 		char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
3448 
3449 		nf_ct_expect_iterate_net(info->net, expect_iter_name, name,
3450 					 NETLINK_CB(skb).portid,
3451 					 nlmsg_report(info->nlh));
3452 	} else {
3453 		/* This basically means we have to flush everything*/
3454 		nf_ct_expect_iterate_net(info->net, expect_iter_all, NULL,
3455 					 NETLINK_CB(skb).portid,
3456 					 nlmsg_report(info->nlh));
3457 	}
3458 
3459 	return 0;
3460 }
3461 static int
ctnetlink_change_expect(struct nf_conntrack_expect * x,const struct nlattr * const cda[])3462 ctnetlink_change_expect(struct nf_conntrack_expect *x,
3463 			const struct nlattr * const cda[])
3464 {
3465 	if (cda[CTA_EXPECT_TIMEOUT]) {
3466 		if (!del_timer(&x->timeout))
3467 			return -ETIME;
3468 
3469 		x->timeout.expires = jiffies +
3470 			ntohl(nla_get_be32(cda[CTA_EXPECT_TIMEOUT])) * HZ;
3471 		add_timer(&x->timeout);
3472 	}
3473 	return 0;
3474 }
3475 
3476 #if IS_ENABLED(CONFIG_NF_NAT)
3477 static const struct nla_policy exp_nat_nla_policy[CTA_EXPECT_NAT_MAX+1] = {
3478 	[CTA_EXPECT_NAT_DIR]	= { .type = NLA_U32 },
3479 	[CTA_EXPECT_NAT_TUPLE]	= { .type = NLA_NESTED },
3480 };
3481 #endif
3482 
3483 static int
ctnetlink_parse_expect_nat(const struct nlattr * attr,struct nf_conntrack_expect * exp,u_int8_t u3)3484 ctnetlink_parse_expect_nat(const struct nlattr *attr,
3485 			   struct nf_conntrack_expect *exp,
3486 			   u_int8_t u3)
3487 {
3488 #if IS_ENABLED(CONFIG_NF_NAT)
3489 	struct nlattr *tb[CTA_EXPECT_NAT_MAX+1];
3490 	struct nf_conntrack_tuple nat_tuple = {};
3491 	int err;
3492 
3493 	err = nla_parse_nested_deprecated(tb, CTA_EXPECT_NAT_MAX, attr,
3494 					  exp_nat_nla_policy, NULL);
3495 	if (err < 0)
3496 		return err;
3497 
3498 	if (!tb[CTA_EXPECT_NAT_DIR] || !tb[CTA_EXPECT_NAT_TUPLE])
3499 		return -EINVAL;
3500 
3501 	err = ctnetlink_parse_tuple((const struct nlattr * const *)tb,
3502 				    &nat_tuple, CTA_EXPECT_NAT_TUPLE,
3503 				    u3, NULL);
3504 	if (err < 0)
3505 		return err;
3506 
3507 	exp->saved_addr = nat_tuple.src.u3;
3508 	exp->saved_proto = nat_tuple.src.u;
3509 	exp->dir = ntohl(nla_get_be32(tb[CTA_EXPECT_NAT_DIR]));
3510 
3511 	return 0;
3512 #else
3513 	return -EOPNOTSUPP;
3514 #endif
3515 }
3516 
3517 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)3518 ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,
3519 		       struct nf_conntrack_helper *helper,
3520 		       struct nf_conntrack_tuple *tuple,
3521 		       struct nf_conntrack_tuple *mask)
3522 {
3523 	u_int32_t class = 0;
3524 	struct nf_conntrack_expect *exp;
3525 	struct nf_conn_help *help;
3526 	int err;
3527 
3528 	help = nfct_help(ct);
3529 	if (!help)
3530 		return ERR_PTR(-EOPNOTSUPP);
3531 
3532 	if (cda[CTA_EXPECT_CLASS] && helper) {
3533 		class = ntohl(nla_get_be32(cda[CTA_EXPECT_CLASS]));
3534 		if (class > helper->expect_class_max)
3535 			return ERR_PTR(-EINVAL);
3536 	}
3537 	exp = nf_ct_expect_alloc(ct);
3538 	if (!exp)
3539 		return ERR_PTR(-ENOMEM);
3540 
3541 	if (cda[CTA_EXPECT_FLAGS]) {
3542 		exp->flags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
3543 		exp->flags &= ~NF_CT_EXPECT_USERSPACE;
3544 	} else {
3545 		exp->flags = 0;
3546 	}
3547 	if (cda[CTA_EXPECT_FN]) {
3548 		const char *name = nla_data(cda[CTA_EXPECT_FN]);
3549 		struct nf_ct_helper_expectfn *expfn;
3550 
3551 		expfn = nf_ct_helper_expectfn_find_by_name(name);
3552 		if (expfn == NULL) {
3553 			err = -EINVAL;
3554 			goto err_out;
3555 		}
3556 		exp->expectfn = expfn->expectfn;
3557 	} else
3558 		exp->expectfn = NULL;
3559 
3560 	exp->class = class;
3561 	exp->master = ct;
3562 	exp->helper = helper;
3563 	exp->tuple = *tuple;
3564 	exp->mask.src.u3 = mask->src.u3;
3565 	exp->mask.src.u.all = mask->src.u.all;
3566 
3567 	if (cda[CTA_EXPECT_NAT]) {
3568 		err = ctnetlink_parse_expect_nat(cda[CTA_EXPECT_NAT],
3569 						 exp, nf_ct_l3num(ct));
3570 		if (err < 0)
3571 			goto err_out;
3572 	}
3573 	return exp;
3574 err_out:
3575 	nf_ct_expect_put(exp);
3576 	return ERR_PTR(err);
3577 }
3578 
3579 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)3580 ctnetlink_create_expect(struct net *net,
3581 			const struct nf_conntrack_zone *zone,
3582 			const struct nlattr * const cda[],
3583 			u_int8_t u3, u32 portid, int report)
3584 {
3585 	struct nf_conntrack_tuple tuple, mask, master_tuple;
3586 	struct nf_conntrack_tuple_hash *h = NULL;
3587 	struct nf_conntrack_helper *helper = NULL;
3588 	struct nf_conntrack_expect *exp;
3589 	struct nf_conn *ct;
3590 	int err;
3591 
3592 	/* caller guarantees that those three CTA_EXPECT_* exist */
3593 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3594 				    u3, NULL);
3595 	if (err < 0)
3596 		return err;
3597 	err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK,
3598 				    u3, NULL);
3599 	if (err < 0)
3600 		return err;
3601 	err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER,
3602 				    u3, NULL);
3603 	if (err < 0)
3604 		return err;
3605 
3606 	/* Look for master conntrack of this expectation */
3607 	h = nf_conntrack_find_get(net, zone, &master_tuple);
3608 	if (!h)
3609 		return -ENOENT;
3610 	ct = nf_ct_tuplehash_to_ctrack(h);
3611 
3612 	rcu_read_lock();
3613 	if (cda[CTA_EXPECT_HELP_NAME]) {
3614 		const char *helpname = nla_data(cda[CTA_EXPECT_HELP_NAME]);
3615 
3616 		helper = __nf_conntrack_helper_find(helpname, u3,
3617 						    nf_ct_protonum(ct));
3618 		if (helper == NULL) {
3619 			rcu_read_unlock();
3620 #ifdef CONFIG_MODULES
3621 			if (request_module("nfct-helper-%s", helpname) < 0) {
3622 				err = -EOPNOTSUPP;
3623 				goto err_ct;
3624 			}
3625 			rcu_read_lock();
3626 			helper = __nf_conntrack_helper_find(helpname, u3,
3627 							    nf_ct_protonum(ct));
3628 			if (helper) {
3629 				err = -EAGAIN;
3630 				goto err_rcu;
3631 			}
3632 			rcu_read_unlock();
3633 #endif
3634 			err = -EOPNOTSUPP;
3635 			goto err_ct;
3636 		}
3637 	}
3638 
3639 	exp = ctnetlink_alloc_expect(cda, ct, helper, &tuple, &mask);
3640 	if (IS_ERR(exp)) {
3641 		err = PTR_ERR(exp);
3642 		goto err_rcu;
3643 	}
3644 
3645 	err = nf_ct_expect_related_report(exp, portid, report, 0);
3646 	nf_ct_expect_put(exp);
3647 err_rcu:
3648 	rcu_read_unlock();
3649 err_ct:
3650 	nf_ct_put(ct);
3651 	return err;
3652 }
3653 
ctnetlink_new_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3654 static int ctnetlink_new_expect(struct sk_buff *skb,
3655 				const struct nfnl_info *info,
3656 				const struct nlattr * const cda[])
3657 {
3658 	u_int8_t u3 = info->nfmsg->nfgen_family;
3659 	struct nf_conntrack_tuple tuple;
3660 	struct nf_conntrack_expect *exp;
3661 	struct nf_conntrack_zone zone;
3662 	int err;
3663 
3664 	if (!cda[CTA_EXPECT_TUPLE]
3665 	    || !cda[CTA_EXPECT_MASK]
3666 	    || !cda[CTA_EXPECT_MASTER])
3667 		return -EINVAL;
3668 
3669 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3670 	if (err < 0)
3671 		return err;
3672 
3673 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3674 				    u3, NULL);
3675 	if (err < 0)
3676 		return err;
3677 
3678 	spin_lock_bh(&nf_conntrack_expect_lock);
3679 	exp = __nf_ct_expect_find(info->net, &zone, &tuple);
3680 	if (!exp) {
3681 		spin_unlock_bh(&nf_conntrack_expect_lock);
3682 		err = -ENOENT;
3683 		if (info->nlh->nlmsg_flags & NLM_F_CREATE) {
3684 			err = ctnetlink_create_expect(info->net, &zone, cda, u3,
3685 						      NETLINK_CB(skb).portid,
3686 						      nlmsg_report(info->nlh));
3687 		}
3688 		return err;
3689 	}
3690 
3691 	err = -EEXIST;
3692 	if (!(info->nlh->nlmsg_flags & NLM_F_EXCL))
3693 		err = ctnetlink_change_expect(exp, cda);
3694 	spin_unlock_bh(&nf_conntrack_expect_lock);
3695 
3696 	return err;
3697 }
3698 
3699 static int
ctnetlink_exp_stat_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int cpu,const struct ip_conntrack_stat * st)3700 ctnetlink_exp_stat_fill_info(struct sk_buff *skb, u32 portid, u32 seq, int cpu,
3701 			     const struct ip_conntrack_stat *st)
3702 {
3703 	struct nlmsghdr *nlh;
3704 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
3705 
3706 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK,
3707 			      IPCTNL_MSG_EXP_GET_STATS_CPU);
3708 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
3709 			   NFNETLINK_V0, htons(cpu));
3710 	if (!nlh)
3711 		goto nlmsg_failure;
3712 
3713 	if (nla_put_be32(skb, CTA_STATS_EXP_NEW, htonl(st->expect_new)) ||
3714 	    nla_put_be32(skb, CTA_STATS_EXP_CREATE, htonl(st->expect_create)) ||
3715 	    nla_put_be32(skb, CTA_STATS_EXP_DELETE, htonl(st->expect_delete)))
3716 		goto nla_put_failure;
3717 
3718 	nlmsg_end(skb, nlh);
3719 	return skb->len;
3720 
3721 nla_put_failure:
3722 nlmsg_failure:
3723 	nlmsg_cancel(skb, nlh);
3724 	return -1;
3725 }
3726 
3727 static int
ctnetlink_exp_stat_cpu_dump(struct sk_buff * skb,struct netlink_callback * cb)3728 ctnetlink_exp_stat_cpu_dump(struct sk_buff *skb, struct netlink_callback *cb)
3729 {
3730 	int cpu;
3731 	struct net *net = sock_net(skb->sk);
3732 
3733 	if (cb->args[0] == nr_cpu_ids)
3734 		return 0;
3735 
3736 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
3737 		const struct ip_conntrack_stat *st;
3738 
3739 		if (!cpu_possible(cpu))
3740 			continue;
3741 
3742 		st = per_cpu_ptr(net->ct.stat, cpu);
3743 		if (ctnetlink_exp_stat_fill_info(skb, NETLINK_CB(cb->skb).portid,
3744 						 cb->nlh->nlmsg_seq,
3745 						 cpu, st) < 0)
3746 			break;
3747 	}
3748 	cb->args[0] = cpu;
3749 
3750 	return skb->len;
3751 }
3752 
ctnetlink_stat_exp_cpu(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3753 static int ctnetlink_stat_exp_cpu(struct sk_buff *skb,
3754 				  const struct nfnl_info *info,
3755 				  const struct nlattr * const cda[])
3756 {
3757 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
3758 		struct netlink_dump_control c = {
3759 			.dump = ctnetlink_exp_stat_cpu_dump,
3760 		};
3761 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
3762 	}
3763 
3764 	return 0;
3765 }
3766 
3767 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3768 static struct nf_ct_event_notifier ctnl_notifier = {
3769 	.ct_event = ctnetlink_conntrack_event,
3770 	.exp_event = ctnetlink_expect_event,
3771 };
3772 #endif
3773 
3774 static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
3775 	[IPCTNL_MSG_CT_NEW]	= {
3776 		.call		= ctnetlink_new_conntrack,
3777 		.type		= NFNL_CB_MUTEX,
3778 		.attr_count	= CTA_MAX,
3779 		.policy		= ct_nla_policy
3780 	},
3781 	[IPCTNL_MSG_CT_GET]	= {
3782 		.call		= ctnetlink_get_conntrack,
3783 		.type		= NFNL_CB_MUTEX,
3784 		.attr_count	= CTA_MAX,
3785 		.policy		= ct_nla_policy
3786 	},
3787 	[IPCTNL_MSG_CT_DELETE]	= {
3788 		.call		= ctnetlink_del_conntrack,
3789 		.type		= NFNL_CB_MUTEX,
3790 		.attr_count	= CTA_MAX,
3791 		.policy		= ct_nla_policy
3792 	},
3793 	[IPCTNL_MSG_CT_GET_CTRZERO] = {
3794 		.call		= ctnetlink_get_conntrack,
3795 		.type		= NFNL_CB_MUTEX,
3796 		.attr_count	= CTA_MAX,
3797 		.policy		= ct_nla_policy
3798 	},
3799 	[IPCTNL_MSG_CT_GET_STATS_CPU] = {
3800 		.call		= ctnetlink_stat_ct_cpu,
3801 		.type		= NFNL_CB_MUTEX,
3802 	},
3803 	[IPCTNL_MSG_CT_GET_STATS] = {
3804 		.call		= ctnetlink_stat_ct,
3805 		.type		= NFNL_CB_MUTEX,
3806 	},
3807 	[IPCTNL_MSG_CT_GET_DYING] = {
3808 		.call		= ctnetlink_get_ct_dying,
3809 		.type		= NFNL_CB_MUTEX,
3810 	},
3811 	[IPCTNL_MSG_CT_GET_UNCONFIRMED]	= {
3812 		.call		= ctnetlink_get_ct_unconfirmed,
3813 		.type		= NFNL_CB_MUTEX,
3814 	},
3815 };
3816 
3817 static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
3818 	[IPCTNL_MSG_EXP_GET] = {
3819 		.call		= ctnetlink_get_expect,
3820 		.type		= NFNL_CB_MUTEX,
3821 		.attr_count	= CTA_EXPECT_MAX,
3822 		.policy		= exp_nla_policy
3823 	},
3824 	[IPCTNL_MSG_EXP_NEW] = {
3825 		.call		= ctnetlink_new_expect,
3826 		.type		= NFNL_CB_MUTEX,
3827 		.attr_count	= CTA_EXPECT_MAX,
3828 		.policy		= exp_nla_policy
3829 	},
3830 	[IPCTNL_MSG_EXP_DELETE] = {
3831 		.call		= ctnetlink_del_expect,
3832 		.type		= NFNL_CB_MUTEX,
3833 		.attr_count	= CTA_EXPECT_MAX,
3834 		.policy		= exp_nla_policy
3835 	},
3836 	[IPCTNL_MSG_EXP_GET_STATS_CPU] = {
3837 		.call		= ctnetlink_stat_exp_cpu,
3838 		.type		= NFNL_CB_MUTEX,
3839 	},
3840 };
3841 
3842 static const struct nfnetlink_subsystem ctnl_subsys = {
3843 	.name				= "conntrack",
3844 	.subsys_id			= NFNL_SUBSYS_CTNETLINK,
3845 	.cb_count			= IPCTNL_MSG_MAX,
3846 	.cb				= ctnl_cb,
3847 };
3848 
3849 static const struct nfnetlink_subsystem ctnl_exp_subsys = {
3850 	.name				= "conntrack_expect",
3851 	.subsys_id			= NFNL_SUBSYS_CTNETLINK_EXP,
3852 	.cb_count			= IPCTNL_MSG_EXP_MAX,
3853 	.cb				= ctnl_exp_cb,
3854 };
3855 
3856 MODULE_ALIAS("ip_conntrack_netlink");
3857 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
3858 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
3859 
ctnetlink_net_init(struct net * net)3860 static int __net_init ctnetlink_net_init(struct net *net)
3861 {
3862 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3863 	nf_conntrack_register_notifier(net, &ctnl_notifier);
3864 #endif
3865 	return 0;
3866 }
3867 
ctnetlink_net_pre_exit(struct net * net)3868 static void ctnetlink_net_pre_exit(struct net *net)
3869 {
3870 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3871 	nf_conntrack_unregister_notifier(net);
3872 #endif
3873 }
3874 
3875 static struct pernet_operations ctnetlink_net_ops = {
3876 	.init		= ctnetlink_net_init,
3877 	.pre_exit	= ctnetlink_net_pre_exit,
3878 };
3879 
ctnetlink_init(void)3880 static int __init ctnetlink_init(void)
3881 {
3882 	int ret;
3883 
3884 	ret = nfnetlink_subsys_register(&ctnl_subsys);
3885 	if (ret < 0) {
3886 		pr_err("ctnetlink_init: cannot register with nfnetlink.\n");
3887 		goto err_out;
3888 	}
3889 
3890 	ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
3891 	if (ret < 0) {
3892 		pr_err("ctnetlink_init: cannot register exp with nfnetlink.\n");
3893 		goto err_unreg_subsys;
3894 	}
3895 
3896 	ret = register_pernet_subsys(&ctnetlink_net_ops);
3897 	if (ret < 0) {
3898 		pr_err("ctnetlink_init: cannot register pernet operations\n");
3899 		goto err_unreg_exp_subsys;
3900 	}
3901 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
3902 	/* setup interaction between nf_queue and nf_conntrack_netlink. */
3903 	RCU_INIT_POINTER(nfnl_ct_hook, &ctnetlink_glue_hook);
3904 #endif
3905 	return 0;
3906 
3907 err_unreg_exp_subsys:
3908 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
3909 err_unreg_subsys:
3910 	nfnetlink_subsys_unregister(&ctnl_subsys);
3911 err_out:
3912 	return ret;
3913 }
3914 
ctnetlink_exit(void)3915 static void __exit ctnetlink_exit(void)
3916 {
3917 	unregister_pernet_subsys(&ctnetlink_net_ops);
3918 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
3919 	nfnetlink_subsys_unregister(&ctnl_subsys);
3920 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
3921 	RCU_INIT_POINTER(nfnl_ct_hook, NULL);
3922 #endif
3923 	synchronize_rcu();
3924 }
3925 
3926 module_init(ctnetlink_init);
3927 module_exit(ctnetlink_exit);
3928