xref: /openbmc/linux/net/netfilter/nf_conntrack_netlink.c (revision 34d6f206a88c2651d216bd3487ac956a40b2ba8e)
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 
61 struct ctnetlink_list_dump_ctx {
62 	struct nf_conn *last;
63 	unsigned int cpu;
64 	bool done;
65 };
66 
ctnetlink_dump_tuples_proto(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_l4proto * l4proto)67 static int ctnetlink_dump_tuples_proto(struct sk_buff *skb,
68 				const struct nf_conntrack_tuple *tuple,
69 				const struct nf_conntrack_l4proto *l4proto)
70 {
71 	int ret = 0;
72 	struct nlattr *nest_parms;
73 
74 	nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO);
75 	if (!nest_parms)
76 		goto nla_put_failure;
77 	if (nla_put_u8(skb, CTA_PROTO_NUM, tuple->dst.protonum))
78 		goto nla_put_failure;
79 
80 	if (likely(l4proto->tuple_to_nlattr))
81 		ret = l4proto->tuple_to_nlattr(skb, tuple);
82 
83 	nla_nest_end(skb, nest_parms);
84 
85 	return ret;
86 
87 nla_put_failure:
88 	return -1;
89 }
90 
ipv4_tuple_to_nlattr(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)91 static int ipv4_tuple_to_nlattr(struct sk_buff *skb,
92 				const struct nf_conntrack_tuple *tuple)
93 {
94 	if (nla_put_in_addr(skb, CTA_IP_V4_SRC, tuple->src.u3.ip) ||
95 	    nla_put_in_addr(skb, CTA_IP_V4_DST, tuple->dst.u3.ip))
96 		return -EMSGSIZE;
97 	return 0;
98 }
99 
ipv6_tuple_to_nlattr(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)100 static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
101 				const struct nf_conntrack_tuple *tuple)
102 {
103 	if (nla_put_in6_addr(skb, CTA_IP_V6_SRC, &tuple->src.u3.in6) ||
104 	    nla_put_in6_addr(skb, CTA_IP_V6_DST, &tuple->dst.u3.in6))
105 		return -EMSGSIZE;
106 	return 0;
107 }
108 
ctnetlink_dump_tuples_ip(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)109 static int ctnetlink_dump_tuples_ip(struct sk_buff *skb,
110 				    const struct nf_conntrack_tuple *tuple)
111 {
112 	int ret = 0;
113 	struct nlattr *nest_parms;
114 
115 	nest_parms = nla_nest_start(skb, CTA_TUPLE_IP);
116 	if (!nest_parms)
117 		goto nla_put_failure;
118 
119 	switch (tuple->src.l3num) {
120 	case NFPROTO_IPV4:
121 		ret = ipv4_tuple_to_nlattr(skb, tuple);
122 		break;
123 	case NFPROTO_IPV6:
124 		ret = ipv6_tuple_to_nlattr(skb, tuple);
125 		break;
126 	}
127 
128 	nla_nest_end(skb, nest_parms);
129 
130 	return ret;
131 
132 nla_put_failure:
133 	return -1;
134 }
135 
ctnetlink_dump_tuples(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)136 static int ctnetlink_dump_tuples(struct sk_buff *skb,
137 				 const struct nf_conntrack_tuple *tuple)
138 {
139 	const struct nf_conntrack_l4proto *l4proto;
140 	int ret;
141 
142 	rcu_read_lock();
143 	ret = ctnetlink_dump_tuples_ip(skb, tuple);
144 
145 	if (ret >= 0) {
146 		l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
147 		ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
148 	}
149 	rcu_read_unlock();
150 	return ret;
151 }
152 
ctnetlink_dump_zone_id(struct sk_buff * skb,int attrtype,const struct nf_conntrack_zone * zone,int dir)153 static int ctnetlink_dump_zone_id(struct sk_buff *skb, int attrtype,
154 				  const struct nf_conntrack_zone *zone, int dir)
155 {
156 	if (zone->id == NF_CT_DEFAULT_ZONE_ID || zone->dir != dir)
157 		return 0;
158 	if (nla_put_be16(skb, attrtype, htons(zone->id)))
159 		goto nla_put_failure;
160 	return 0;
161 
162 nla_put_failure:
163 	return -1;
164 }
165 
ctnetlink_dump_status(struct sk_buff * skb,const struct nf_conn * ct)166 static int ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
167 {
168 	if (nla_put_be32(skb, CTA_STATUS, htonl(ct->status)))
169 		goto nla_put_failure;
170 	return 0;
171 
172 nla_put_failure:
173 	return -1;
174 }
175 
ctnetlink_dump_timeout(struct sk_buff * skb,const struct nf_conn * ct,bool skip_zero)176 static int ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct,
177 				  bool skip_zero)
178 {
179 	long timeout;
180 
181 	if (nf_ct_is_confirmed(ct))
182 		timeout = nf_ct_expires(ct) / HZ;
183 	else
184 		timeout = ct->timeout / HZ;
185 
186 	if (skip_zero && timeout == 0)
187 		return 0;
188 
189 	if (nla_put_be32(skb, CTA_TIMEOUT, htonl(timeout)))
190 		goto nla_put_failure;
191 	return 0;
192 
193 nla_put_failure:
194 	return -1;
195 }
196 
ctnetlink_dump_protoinfo(struct sk_buff * skb,struct nf_conn * ct,bool destroy)197 static int ctnetlink_dump_protoinfo(struct sk_buff *skb, struct nf_conn *ct,
198 				    bool destroy)
199 {
200 	const struct nf_conntrack_l4proto *l4proto;
201 	struct nlattr *nest_proto;
202 	int ret;
203 
204 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
205 	if (!l4proto->to_nlattr)
206 		return 0;
207 
208 	nest_proto = nla_nest_start(skb, CTA_PROTOINFO);
209 	if (!nest_proto)
210 		goto nla_put_failure;
211 
212 	ret = l4proto->to_nlattr(skb, nest_proto, ct, destroy);
213 
214 	nla_nest_end(skb, nest_proto);
215 
216 	return ret;
217 
218 nla_put_failure:
219 	return -1;
220 }
221 
ctnetlink_dump_helpinfo(struct sk_buff * skb,const struct nf_conn * ct)222 static int ctnetlink_dump_helpinfo(struct sk_buff *skb,
223 				   const struct nf_conn *ct)
224 {
225 	struct nlattr *nest_helper;
226 	const struct nf_conn_help *help = nfct_help(ct);
227 	struct nf_conntrack_helper *helper;
228 
229 	if (!help)
230 		return 0;
231 
232 	rcu_read_lock();
233 	helper = rcu_dereference(help->helper);
234 	if (!helper)
235 		goto out;
236 
237 	nest_helper = nla_nest_start(skb, CTA_HELP);
238 	if (!nest_helper)
239 		goto nla_put_failure;
240 	if (nla_put_string(skb, CTA_HELP_NAME, helper->name))
241 		goto nla_put_failure;
242 
243 	if (helper->to_nlattr)
244 		helper->to_nlattr(skb, ct);
245 
246 	nla_nest_end(skb, nest_helper);
247 out:
248 	rcu_read_unlock();
249 	return 0;
250 
251 nla_put_failure:
252 	rcu_read_unlock();
253 	return -1;
254 }
255 
256 static int
dump_counters(struct sk_buff * skb,struct nf_conn_acct * acct,enum ip_conntrack_dir dir,int type)257 dump_counters(struct sk_buff *skb, struct nf_conn_acct *acct,
258 	      enum ip_conntrack_dir dir, int type)
259 {
260 	enum ctattr_type attr = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
261 	struct nf_conn_counter *counter = acct->counter;
262 	struct nlattr *nest_count;
263 	u64 pkts, bytes;
264 
265 	if (type == IPCTNL_MSG_CT_GET_CTRZERO) {
266 		pkts = atomic64_xchg(&counter[dir].packets, 0);
267 		bytes = atomic64_xchg(&counter[dir].bytes, 0);
268 	} else {
269 		pkts = atomic64_read(&counter[dir].packets);
270 		bytes = atomic64_read(&counter[dir].bytes);
271 	}
272 
273 	nest_count = nla_nest_start(skb, attr);
274 	if (!nest_count)
275 		goto nla_put_failure;
276 
277 	if (nla_put_be64(skb, CTA_COUNTERS_PACKETS, cpu_to_be64(pkts),
278 			 CTA_COUNTERS_PAD) ||
279 	    nla_put_be64(skb, CTA_COUNTERS_BYTES, cpu_to_be64(bytes),
280 			 CTA_COUNTERS_PAD))
281 		goto nla_put_failure;
282 
283 	nla_nest_end(skb, nest_count);
284 
285 	return 0;
286 
287 nla_put_failure:
288 	return -1;
289 }
290 
291 static int
ctnetlink_dump_acct(struct sk_buff * skb,const struct nf_conn * ct,int type)292 ctnetlink_dump_acct(struct sk_buff *skb, const struct nf_conn *ct, int type)
293 {
294 	struct nf_conn_acct *acct = nf_conn_acct_find(ct);
295 
296 	if (!acct)
297 		return 0;
298 
299 	if (dump_counters(skb, acct, IP_CT_DIR_ORIGINAL, type) < 0)
300 		return -1;
301 	if (dump_counters(skb, acct, IP_CT_DIR_REPLY, type) < 0)
302 		return -1;
303 
304 	return 0;
305 }
306 
307 static int
ctnetlink_dump_timestamp(struct sk_buff * skb,const struct nf_conn * ct)308 ctnetlink_dump_timestamp(struct sk_buff *skb, const struct nf_conn *ct)
309 {
310 	struct nlattr *nest_count;
311 	const struct nf_conn_tstamp *tstamp;
312 
313 	tstamp = nf_conn_tstamp_find(ct);
314 	if (!tstamp)
315 		return 0;
316 
317 	nest_count = nla_nest_start(skb, CTA_TIMESTAMP);
318 	if (!nest_count)
319 		goto nla_put_failure;
320 
321 	if (nla_put_be64(skb, CTA_TIMESTAMP_START, cpu_to_be64(tstamp->start),
322 			 CTA_TIMESTAMP_PAD) ||
323 	    (tstamp->stop != 0 && nla_put_be64(skb, CTA_TIMESTAMP_STOP,
324 					       cpu_to_be64(tstamp->stop),
325 					       CTA_TIMESTAMP_PAD)))
326 		goto nla_put_failure;
327 	nla_nest_end(skb, nest_count);
328 
329 	return 0;
330 
331 nla_put_failure:
332 	return -1;
333 }
334 
335 #ifdef CONFIG_NF_CONNTRACK_MARK
ctnetlink_dump_mark(struct sk_buff * skb,const struct nf_conn * ct,bool dump)336 static int ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct,
337 			       bool dump)
338 {
339 	u32 mark = READ_ONCE(ct->mark);
340 
341 	if (!mark && !dump)
342 		return 0;
343 
344 	if (nla_put_be32(skb, CTA_MARK, htonl(mark)))
345 		goto nla_put_failure;
346 	return 0;
347 
348 nla_put_failure:
349 	return -1;
350 }
351 #else
352 #define ctnetlink_dump_mark(a, b, c) (0)
353 #endif
354 
355 #ifdef CONFIG_NF_CONNTRACK_SECMARK
ctnetlink_dump_secctx(struct sk_buff * skb,const struct nf_conn * ct)356 static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
357 {
358 	struct nlattr *nest_secctx;
359 	int len, ret;
360 	char *secctx;
361 
362 	ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
363 	if (ret)
364 		return 0;
365 
366 	ret = -1;
367 	nest_secctx = nla_nest_start(skb, CTA_SECCTX);
368 	if (!nest_secctx)
369 		goto nla_put_failure;
370 
371 	if (nla_put_string(skb, CTA_SECCTX_NAME, secctx))
372 		goto nla_put_failure;
373 	nla_nest_end(skb, nest_secctx);
374 
375 	ret = 0;
376 nla_put_failure:
377 	security_release_secctx(secctx, len);
378 	return ret;
379 }
380 #else
381 #define ctnetlink_dump_secctx(a, b) (0)
382 #endif
383 
384 #ifdef CONFIG_NF_CONNTRACK_EVENTS
ctnetlink_label_size(const struct nf_conn * ct)385 static inline int ctnetlink_label_size(const struct nf_conn *ct)
386 {
387 	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
388 
389 	if (!labels)
390 		return 0;
391 	return nla_total_size(sizeof(labels->bits));
392 }
393 #endif
394 
395 static int
ctnetlink_dump_labels(struct sk_buff * skb,const struct nf_conn * ct)396 ctnetlink_dump_labels(struct sk_buff *skb, const struct nf_conn *ct)
397 {
398 	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
399 	unsigned int i;
400 
401 	if (!labels)
402 		return 0;
403 
404 	i = 0;
405 	do {
406 		if (labels->bits[i] != 0)
407 			return nla_put(skb, CTA_LABELS, sizeof(labels->bits),
408 				       labels->bits);
409 		i++;
410 	} while (i < ARRAY_SIZE(labels->bits));
411 
412 	return 0;
413 }
414 
415 #define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
416 
ctnetlink_dump_master(struct sk_buff * skb,const struct nf_conn * ct)417 static int ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
418 {
419 	struct nlattr *nest_parms;
420 
421 	if (!(ct->status & IPS_EXPECTED))
422 		return 0;
423 
424 	nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER);
425 	if (!nest_parms)
426 		goto nla_put_failure;
427 	if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
428 		goto nla_put_failure;
429 	nla_nest_end(skb, nest_parms);
430 
431 	return 0;
432 
433 nla_put_failure:
434 	return -1;
435 }
436 
437 static int
dump_ct_seq_adj(struct sk_buff * skb,const struct nf_ct_seqadj * seq,int type)438 dump_ct_seq_adj(struct sk_buff *skb, const struct nf_ct_seqadj *seq, int type)
439 {
440 	struct nlattr *nest_parms;
441 
442 	nest_parms = nla_nest_start(skb, type);
443 	if (!nest_parms)
444 		goto nla_put_failure;
445 
446 	if (nla_put_be32(skb, CTA_SEQADJ_CORRECTION_POS,
447 			 htonl(seq->correction_pos)) ||
448 	    nla_put_be32(skb, CTA_SEQADJ_OFFSET_BEFORE,
449 			 htonl(seq->offset_before)) ||
450 	    nla_put_be32(skb, CTA_SEQADJ_OFFSET_AFTER,
451 			 htonl(seq->offset_after)))
452 		goto nla_put_failure;
453 
454 	nla_nest_end(skb, nest_parms);
455 
456 	return 0;
457 
458 nla_put_failure:
459 	return -1;
460 }
461 
ctnetlink_dump_ct_seq_adj(struct sk_buff * skb,struct nf_conn * ct)462 static int ctnetlink_dump_ct_seq_adj(struct sk_buff *skb, struct nf_conn *ct)
463 {
464 	struct nf_conn_seqadj *seqadj = nfct_seqadj(ct);
465 	struct nf_ct_seqadj *seq;
466 
467 	if (!(ct->status & IPS_SEQ_ADJUST) || !seqadj)
468 		return 0;
469 
470 	spin_lock_bh(&ct->lock);
471 	seq = &seqadj->seq[IP_CT_DIR_ORIGINAL];
472 	if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_ORIG) == -1)
473 		goto err;
474 
475 	seq = &seqadj->seq[IP_CT_DIR_REPLY];
476 	if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_REPLY) == -1)
477 		goto err;
478 
479 	spin_unlock_bh(&ct->lock);
480 	return 0;
481 err:
482 	spin_unlock_bh(&ct->lock);
483 	return -1;
484 }
485 
ctnetlink_dump_ct_synproxy(struct sk_buff * skb,struct nf_conn * ct)486 static int ctnetlink_dump_ct_synproxy(struct sk_buff *skb, struct nf_conn *ct)
487 {
488 	struct nf_conn_synproxy *synproxy = nfct_synproxy(ct);
489 	struct nlattr *nest_parms;
490 
491 	if (!synproxy)
492 		return 0;
493 
494 	nest_parms = nla_nest_start(skb, CTA_SYNPROXY);
495 	if (!nest_parms)
496 		goto nla_put_failure;
497 
498 	if (nla_put_be32(skb, CTA_SYNPROXY_ISN, htonl(synproxy->isn)) ||
499 	    nla_put_be32(skb, CTA_SYNPROXY_ITS, htonl(synproxy->its)) ||
500 	    nla_put_be32(skb, CTA_SYNPROXY_TSOFF, htonl(synproxy->tsoff)))
501 		goto nla_put_failure;
502 
503 	nla_nest_end(skb, nest_parms);
504 
505 	return 0;
506 
507 nla_put_failure:
508 	return -1;
509 }
510 
ctnetlink_dump_id(struct sk_buff * skb,const struct nf_conn * ct)511 static int ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
512 {
513 	__be32 id = (__force __be32)nf_ct_get_id(ct);
514 
515 	if (nla_put_be32(skb, CTA_ID, id))
516 		goto nla_put_failure;
517 	return 0;
518 
519 nla_put_failure:
520 	return -1;
521 }
522 
ctnetlink_dump_use(struct sk_buff * skb,const struct nf_conn * ct)523 static int ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
524 {
525 	if (nla_put_be32(skb, CTA_USE, htonl(refcount_read(&ct->ct_general.use))))
526 		goto nla_put_failure;
527 	return 0;
528 
529 nla_put_failure:
530 	return -1;
531 }
532 
533 /* all these functions access ct->ext. Caller must either hold a reference
534  * on ct or prevent its deletion by holding either the bucket spinlock or
535  * pcpu dying list lock.
536  */
ctnetlink_dump_extinfo(struct sk_buff * skb,struct nf_conn * ct,u32 type)537 static int ctnetlink_dump_extinfo(struct sk_buff *skb,
538 				  struct nf_conn *ct, u32 type)
539 {
540 	if (ctnetlink_dump_acct(skb, ct, type) < 0 ||
541 	    ctnetlink_dump_timestamp(skb, ct) < 0 ||
542 	    ctnetlink_dump_helpinfo(skb, ct) < 0 ||
543 	    ctnetlink_dump_labels(skb, ct) < 0 ||
544 	    ctnetlink_dump_ct_seq_adj(skb, ct) < 0 ||
545 	    ctnetlink_dump_ct_synproxy(skb, ct) < 0)
546 		return -1;
547 
548 	return 0;
549 }
550 
ctnetlink_dump_info(struct sk_buff * skb,struct nf_conn * ct)551 static int ctnetlink_dump_info(struct sk_buff *skb, struct nf_conn *ct)
552 {
553 	if (ctnetlink_dump_status(skb, ct) < 0 ||
554 	    ctnetlink_dump_mark(skb, ct, true) < 0 ||
555 	    ctnetlink_dump_secctx(skb, ct) < 0 ||
556 	    ctnetlink_dump_id(skb, ct) < 0 ||
557 	    ctnetlink_dump_use(skb, ct) < 0 ||
558 	    ctnetlink_dump_master(skb, ct) < 0)
559 		return -1;
560 
561 	if (!test_bit(IPS_OFFLOAD_BIT, &ct->status) &&
562 	    (ctnetlink_dump_timeout(skb, ct, false) < 0 ||
563 	     ctnetlink_dump_protoinfo(skb, ct, false) < 0))
564 		return -1;
565 
566 	return 0;
567 }
568 
569 static int
ctnetlink_fill_info(struct sk_buff * skb,u32 portid,u32 seq,u32 type,struct nf_conn * ct,bool extinfo,unsigned int flags)570 ctnetlink_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
571 		    struct nf_conn *ct, bool extinfo, unsigned int flags)
572 {
573 	const struct nf_conntrack_zone *zone;
574 	struct nlmsghdr *nlh;
575 	struct nlattr *nest_parms;
576 	unsigned int event;
577 
578 	if (portid)
579 		flags |= NLM_F_MULTI;
580 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_NEW);
581 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, nf_ct_l3num(ct),
582 			   NFNETLINK_V0, 0);
583 	if (!nlh)
584 		goto nlmsg_failure;
585 
586 	zone = nf_ct_zone(ct);
587 
588 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
589 	if (!nest_parms)
590 		goto nla_put_failure;
591 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
592 		goto nla_put_failure;
593 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
594 				   NF_CT_ZONE_DIR_ORIG) < 0)
595 		goto nla_put_failure;
596 	nla_nest_end(skb, nest_parms);
597 
598 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
599 	if (!nest_parms)
600 		goto nla_put_failure;
601 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
602 		goto nla_put_failure;
603 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
604 				   NF_CT_ZONE_DIR_REPL) < 0)
605 		goto nla_put_failure;
606 	nla_nest_end(skb, nest_parms);
607 
608 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
609 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
610 		goto nla_put_failure;
611 
612 	if (ctnetlink_dump_info(skb, ct) < 0)
613 		goto nla_put_failure;
614 	if (extinfo && ctnetlink_dump_extinfo(skb, ct, type) < 0)
615 		goto nla_put_failure;
616 
617 	nlmsg_end(skb, nlh);
618 	return skb->len;
619 
620 nlmsg_failure:
621 nla_put_failure:
622 	nlmsg_cancel(skb, nlh);
623 	return -1;
624 }
625 
626 static const struct nla_policy cta_ip_nla_policy[CTA_IP_MAX + 1] = {
627 	[CTA_IP_V4_SRC]	= { .type = NLA_U32 },
628 	[CTA_IP_V4_DST]	= { .type = NLA_U32 },
629 	[CTA_IP_V6_SRC]	= { .len = sizeof(__be32) * 4 },
630 	[CTA_IP_V6_DST]	= { .len = sizeof(__be32) * 4 },
631 };
632 
633 #if defined(CONFIG_NETFILTER_NETLINK_GLUE_CT) || defined(CONFIG_NF_CONNTRACK_EVENTS)
ctnetlink_proto_size(const struct nf_conn * ct)634 static size_t ctnetlink_proto_size(const struct nf_conn *ct)
635 {
636 	const struct nf_conntrack_l4proto *l4proto;
637 	size_t len, len4 = 0;
638 
639 	len = nla_policy_len(cta_ip_nla_policy, CTA_IP_MAX + 1);
640 	len *= 3u; /* ORIG, REPLY, MASTER */
641 
642 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
643 	len += l4proto->nlattr_size;
644 	if (l4proto->nlattr_tuple_size) {
645 		len4 = l4proto->nlattr_tuple_size();
646 		len4 *= 3u; /* ORIG, REPLY, MASTER */
647 	}
648 
649 	return len + len4;
650 }
651 #endif
652 
ctnetlink_acct_size(const struct nf_conn * ct)653 static inline size_t ctnetlink_acct_size(const struct nf_conn *ct)
654 {
655 	if (!nf_ct_ext_exist(ct, NF_CT_EXT_ACCT))
656 		return 0;
657 	return 2 * nla_total_size(0) /* CTA_COUNTERS_ORIG|REPL */
658 	       + 2 * nla_total_size_64bit(sizeof(uint64_t)) /* CTA_COUNTERS_PACKETS */
659 	       + 2 * nla_total_size_64bit(sizeof(uint64_t)) /* CTA_COUNTERS_BYTES */
660 	       ;
661 }
662 
ctnetlink_secctx_size(const struct nf_conn * ct)663 static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
664 {
665 #ifdef CONFIG_NF_CONNTRACK_SECMARK
666 	int len, ret;
667 
668 	ret = security_secid_to_secctx(ct->secmark, NULL, &len);
669 	if (ret)
670 		return 0;
671 
672 	return nla_total_size(0) /* CTA_SECCTX */
673 	       + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
674 #else
675 	return 0;
676 #endif
677 }
678 
ctnetlink_timestamp_size(const struct nf_conn * ct)679 static inline size_t ctnetlink_timestamp_size(const struct nf_conn *ct)
680 {
681 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
682 	if (!nf_ct_ext_exist(ct, NF_CT_EXT_TSTAMP))
683 		return 0;
684 	return nla_total_size(0) + 2 * nla_total_size_64bit(sizeof(uint64_t));
685 #else
686 	return 0;
687 #endif
688 }
689 
690 #ifdef CONFIG_NF_CONNTRACK_EVENTS
ctnetlink_nlmsg_size(const struct nf_conn * ct)691 static size_t ctnetlink_nlmsg_size(const struct nf_conn *ct)
692 {
693 	return NLMSG_ALIGN(sizeof(struct nfgenmsg))
694 	       + 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
695 	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
696 	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
697 	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
698 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
699 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
700 	       + ctnetlink_acct_size(ct)
701 	       + ctnetlink_timestamp_size(ct)
702 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
703 	       + nla_total_size(0) /* CTA_PROTOINFO */
704 	       + nla_total_size(0) /* CTA_HELP */
705 	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
706 	       + ctnetlink_secctx_size(ct)
707 #if IS_ENABLED(CONFIG_NF_NAT)
708 	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
709 	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
710 #endif
711 #ifdef CONFIG_NF_CONNTRACK_MARK
712 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
713 #endif
714 #ifdef CONFIG_NF_CONNTRACK_ZONES
715 	       + nla_total_size(sizeof(u_int16_t)) /* CTA_ZONE|CTA_TUPLE_ZONE */
716 #endif
717 	       + ctnetlink_proto_size(ct)
718 	       + ctnetlink_label_size(ct)
719 	       ;
720 }
721 
722 static int
ctnetlink_conntrack_event(unsigned int events,const struct nf_ct_event * item)723 ctnetlink_conntrack_event(unsigned int events, const struct nf_ct_event *item)
724 {
725 	const struct nf_conntrack_zone *zone;
726 	struct net *net;
727 	struct nlmsghdr *nlh;
728 	struct nlattr *nest_parms;
729 	struct nf_conn *ct = item->ct;
730 	struct sk_buff *skb;
731 	unsigned int type;
732 	unsigned int flags = 0, group;
733 	int err;
734 
735 	if (events & (1 << IPCT_DESTROY)) {
736 		type = IPCTNL_MSG_CT_DELETE;
737 		group = NFNLGRP_CONNTRACK_DESTROY;
738 	} else if (events & ((1 << IPCT_NEW) | (1 << IPCT_RELATED))) {
739 		type = IPCTNL_MSG_CT_NEW;
740 		flags = NLM_F_CREATE|NLM_F_EXCL;
741 		group = NFNLGRP_CONNTRACK_NEW;
742 	} else if (events) {
743 		type = IPCTNL_MSG_CT_NEW;
744 		group = NFNLGRP_CONNTRACK_UPDATE;
745 	} else
746 		return 0;
747 
748 	net = nf_ct_net(ct);
749 	if (!item->report && !nfnetlink_has_listeners(net, group))
750 		return 0;
751 
752 	skb = nlmsg_new(ctnetlink_nlmsg_size(ct), GFP_ATOMIC);
753 	if (skb == NULL)
754 		goto errout;
755 
756 	type = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, type);
757 	nlh = nfnl_msg_put(skb, item->portid, 0, type, flags, nf_ct_l3num(ct),
758 			   NFNETLINK_V0, 0);
759 	if (!nlh)
760 		goto nlmsg_failure;
761 
762 	zone = nf_ct_zone(ct);
763 
764 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
765 	if (!nest_parms)
766 		goto nla_put_failure;
767 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
768 		goto nla_put_failure;
769 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
770 				   NF_CT_ZONE_DIR_ORIG) < 0)
771 		goto nla_put_failure;
772 	nla_nest_end(skb, nest_parms);
773 
774 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
775 	if (!nest_parms)
776 		goto nla_put_failure;
777 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
778 		goto nla_put_failure;
779 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
780 				   NF_CT_ZONE_DIR_REPL) < 0)
781 		goto nla_put_failure;
782 	nla_nest_end(skb, nest_parms);
783 
784 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
785 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
786 		goto nla_put_failure;
787 
788 	if (ctnetlink_dump_id(skb, ct) < 0)
789 		goto nla_put_failure;
790 
791 	if (ctnetlink_dump_status(skb, ct) < 0)
792 		goto nla_put_failure;
793 
794 	if (events & (1 << IPCT_DESTROY)) {
795 		if (ctnetlink_dump_timeout(skb, ct, true) < 0)
796 			goto nla_put_failure;
797 
798 		if (ctnetlink_dump_acct(skb, ct, type) < 0 ||
799 		    ctnetlink_dump_timestamp(skb, ct) < 0 ||
800 		    ctnetlink_dump_protoinfo(skb, ct, true) < 0)
801 			goto nla_put_failure;
802 	} else {
803 		if (ctnetlink_dump_timeout(skb, ct, false) < 0)
804 			goto nla_put_failure;
805 
806 		if (events & (1 << IPCT_PROTOINFO) &&
807 		    ctnetlink_dump_protoinfo(skb, ct, false) < 0)
808 			goto nla_put_failure;
809 
810 		if ((events & (1 << IPCT_HELPER) || nfct_help(ct))
811 		    && ctnetlink_dump_helpinfo(skb, ct) < 0)
812 			goto nla_put_failure;
813 
814 #ifdef CONFIG_NF_CONNTRACK_SECMARK
815 		if ((events & (1 << IPCT_SECMARK) || ct->secmark)
816 		    && ctnetlink_dump_secctx(skb, ct) < 0)
817 			goto nla_put_failure;
818 #endif
819 		if (events & (1 << IPCT_LABEL) &&
820 		     ctnetlink_dump_labels(skb, ct) < 0)
821 			goto nla_put_failure;
822 
823 		if (events & (1 << IPCT_RELATED) &&
824 		    ctnetlink_dump_master(skb, ct) < 0)
825 			goto nla_put_failure;
826 
827 		if (events & (1 << IPCT_SEQADJ) &&
828 		    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
829 			goto nla_put_failure;
830 
831 		if (events & (1 << IPCT_SYNPROXY) &&
832 		    ctnetlink_dump_ct_synproxy(skb, ct) < 0)
833 			goto nla_put_failure;
834 	}
835 
836 #ifdef CONFIG_NF_CONNTRACK_MARK
837 	if (ctnetlink_dump_mark(skb, ct, events & (1 << IPCT_MARK)))
838 		goto nla_put_failure;
839 #endif
840 	nlmsg_end(skb, nlh);
841 	err = nfnetlink_send(skb, net, item->portid, group, item->report,
842 			     GFP_ATOMIC);
843 	if (err == -ENOBUFS || err == -EAGAIN)
844 		return -ENOBUFS;
845 
846 	return 0;
847 
848 nla_put_failure:
849 	nlmsg_cancel(skb, nlh);
850 nlmsg_failure:
851 	kfree_skb(skb);
852 errout:
853 	if (nfnetlink_set_err(net, 0, group, -ENOBUFS) > 0)
854 		return -ENOBUFS;
855 
856 	return 0;
857 }
858 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
859 
ctnetlink_done(struct netlink_callback * cb)860 static int ctnetlink_done(struct netlink_callback *cb)
861 {
862 	if (cb->args[1])
863 		nf_ct_put((struct nf_conn *)cb->args[1]);
864 	kfree(cb->data);
865 	return 0;
866 }
867 
868 struct ctnetlink_filter_u32 {
869 	u32 val;
870 	u32 mask;
871 };
872 
873 struct ctnetlink_filter {
874 	u8 family;
875 
876 	u_int32_t orig_flags;
877 	u_int32_t reply_flags;
878 
879 	struct nf_conntrack_tuple orig;
880 	struct nf_conntrack_tuple reply;
881 	struct nf_conntrack_zone zone;
882 
883 	struct ctnetlink_filter_u32 mark;
884 	struct ctnetlink_filter_u32 status;
885 };
886 
887 static const struct nla_policy cta_filter_nla_policy[CTA_FILTER_MAX + 1] = {
888 	[CTA_FILTER_ORIG_FLAGS]		= { .type = NLA_U32 },
889 	[CTA_FILTER_REPLY_FLAGS]	= { .type = NLA_U32 },
890 };
891 
ctnetlink_parse_filter(const struct nlattr * attr,struct ctnetlink_filter * filter)892 static int ctnetlink_parse_filter(const struct nlattr *attr,
893 				  struct ctnetlink_filter *filter)
894 {
895 	struct nlattr *tb[CTA_FILTER_MAX + 1];
896 	int ret = 0;
897 
898 	ret = nla_parse_nested(tb, CTA_FILTER_MAX, attr, cta_filter_nla_policy,
899 			       NULL);
900 	if (ret)
901 		return ret;
902 
903 	if (tb[CTA_FILTER_ORIG_FLAGS]) {
904 		filter->orig_flags = nla_get_u32(tb[CTA_FILTER_ORIG_FLAGS]);
905 		if (filter->orig_flags & ~CTA_FILTER_F_ALL)
906 			return -EOPNOTSUPP;
907 	}
908 
909 	if (tb[CTA_FILTER_REPLY_FLAGS]) {
910 		filter->reply_flags = nla_get_u32(tb[CTA_FILTER_REPLY_FLAGS]);
911 		if (filter->reply_flags & ~CTA_FILTER_F_ALL)
912 			return -EOPNOTSUPP;
913 	}
914 
915 	return 0;
916 }
917 
918 static int ctnetlink_parse_zone(const struct nlattr *attr,
919 				struct nf_conntrack_zone *zone);
920 static int ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
921 					 struct nf_conntrack_tuple *tuple,
922 					 u32 type, u_int8_t l3num,
923 					 struct nf_conntrack_zone *zone,
924 					 u_int32_t flags);
925 
ctnetlink_filter_parse_mark(struct ctnetlink_filter_u32 * mark,const struct nlattr * const cda[])926 static int ctnetlink_filter_parse_mark(struct ctnetlink_filter_u32 *mark,
927 				       const struct nlattr * const cda[])
928 {
929 #ifdef CONFIG_NF_CONNTRACK_MARK
930 	if (cda[CTA_MARK]) {
931 		mark->val = ntohl(nla_get_be32(cda[CTA_MARK]));
932 
933 		if (cda[CTA_MARK_MASK])
934 			mark->mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
935 		else
936 			mark->mask = 0xffffffff;
937 	} else if (cda[CTA_MARK_MASK]) {
938 		return -EINVAL;
939 	}
940 #endif
941 	return 0;
942 }
943 
ctnetlink_filter_parse_status(struct ctnetlink_filter_u32 * status,const struct nlattr * const cda[])944 static int ctnetlink_filter_parse_status(struct ctnetlink_filter_u32 *status,
945 					 const struct nlattr * const cda[])
946 {
947 	if (cda[CTA_STATUS]) {
948 		status->val = ntohl(nla_get_be32(cda[CTA_STATUS]));
949 		if (cda[CTA_STATUS_MASK])
950 			status->mask = ntohl(nla_get_be32(cda[CTA_STATUS_MASK]));
951 		else
952 			status->mask = status->val;
953 
954 		/* status->val == 0? always true, else always false. */
955 		if (status->mask == 0)
956 			return -EINVAL;
957 	} else if (cda[CTA_STATUS_MASK]) {
958 		return -EINVAL;
959 	}
960 
961 	/* CTA_STATUS is NLA_U32, if this fires UAPI needs to be extended */
962 	BUILD_BUG_ON(__IPS_MAX_BIT >= 32);
963 	return 0;
964 }
965 
966 static struct ctnetlink_filter *
ctnetlink_alloc_filter(const struct nlattr * const cda[],u8 family)967 ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
968 {
969 	struct ctnetlink_filter *filter;
970 	int err;
971 
972 #ifndef CONFIG_NF_CONNTRACK_MARK
973 	if (cda[CTA_MARK] || cda[CTA_MARK_MASK])
974 		return ERR_PTR(-EOPNOTSUPP);
975 #endif
976 
977 	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
978 	if (filter == NULL)
979 		return ERR_PTR(-ENOMEM);
980 
981 	filter->family = family;
982 
983 	err = ctnetlink_filter_parse_mark(&filter->mark, cda);
984 	if (err)
985 		goto err_filter;
986 
987 	err = ctnetlink_filter_parse_status(&filter->status, cda);
988 	if (err)
989 		goto err_filter;
990 
991 	if (!cda[CTA_FILTER])
992 		return filter;
993 
994 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &filter->zone);
995 	if (err < 0)
996 		goto err_filter;
997 
998 	err = ctnetlink_parse_filter(cda[CTA_FILTER], filter);
999 	if (err < 0)
1000 		goto err_filter;
1001 
1002 	if (filter->orig_flags) {
1003 		if (!cda[CTA_TUPLE_ORIG]) {
1004 			err = -EINVAL;
1005 			goto err_filter;
1006 		}
1007 
1008 		err = ctnetlink_parse_tuple_filter(cda, &filter->orig,
1009 						   CTA_TUPLE_ORIG,
1010 						   filter->family,
1011 						   &filter->zone,
1012 						   filter->orig_flags);
1013 		if (err < 0)
1014 			goto err_filter;
1015 	}
1016 
1017 	if (filter->reply_flags) {
1018 		if (!cda[CTA_TUPLE_REPLY]) {
1019 			err = -EINVAL;
1020 			goto err_filter;
1021 		}
1022 
1023 		err = ctnetlink_parse_tuple_filter(cda, &filter->reply,
1024 						   CTA_TUPLE_REPLY,
1025 						   filter->family,
1026 						   &filter->zone,
1027 						   filter->reply_flags);
1028 		if (err < 0)
1029 			goto err_filter;
1030 	}
1031 
1032 	return filter;
1033 
1034 err_filter:
1035 	kfree(filter);
1036 
1037 	return ERR_PTR(err);
1038 }
1039 
ctnetlink_needs_filter(u8 family,const struct nlattr * const * cda)1040 static bool ctnetlink_needs_filter(u8 family, const struct nlattr * const *cda)
1041 {
1042 	return family || cda[CTA_MARK] || cda[CTA_FILTER] || cda[CTA_STATUS];
1043 }
1044 
ctnetlink_start(struct netlink_callback * cb)1045 static int ctnetlink_start(struct netlink_callback *cb)
1046 {
1047 	const struct nlattr * const *cda = cb->data;
1048 	struct ctnetlink_filter *filter = NULL;
1049 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1050 	u8 family = nfmsg->nfgen_family;
1051 
1052 	if (ctnetlink_needs_filter(family, cda)) {
1053 		filter = ctnetlink_alloc_filter(cda, family);
1054 		if (IS_ERR(filter))
1055 			return PTR_ERR(filter);
1056 	}
1057 
1058 	cb->data = filter;
1059 	return 0;
1060 }
1061 
ctnetlink_filter_match_tuple(struct nf_conntrack_tuple * filter_tuple,struct nf_conntrack_tuple * ct_tuple,u_int32_t flags,int family)1062 static int ctnetlink_filter_match_tuple(struct nf_conntrack_tuple *filter_tuple,
1063 					struct nf_conntrack_tuple *ct_tuple,
1064 					u_int32_t flags, int family)
1065 {
1066 	switch (family) {
1067 	case NFPROTO_IPV4:
1068 		if ((flags & CTA_FILTER_FLAG(CTA_IP_SRC)) &&
1069 		    filter_tuple->src.u3.ip != ct_tuple->src.u3.ip)
1070 			return  0;
1071 
1072 		if ((flags & CTA_FILTER_FLAG(CTA_IP_DST)) &&
1073 		    filter_tuple->dst.u3.ip != ct_tuple->dst.u3.ip)
1074 			return  0;
1075 		break;
1076 	case NFPROTO_IPV6:
1077 		if ((flags & CTA_FILTER_FLAG(CTA_IP_SRC)) &&
1078 		    !ipv6_addr_cmp(&filter_tuple->src.u3.in6,
1079 				   &ct_tuple->src.u3.in6))
1080 			return 0;
1081 
1082 		if ((flags & CTA_FILTER_FLAG(CTA_IP_DST)) &&
1083 		    !ipv6_addr_cmp(&filter_tuple->dst.u3.in6,
1084 				   &ct_tuple->dst.u3.in6))
1085 			return 0;
1086 		break;
1087 	}
1088 
1089 	if ((flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)) &&
1090 	    filter_tuple->dst.protonum != ct_tuple->dst.protonum)
1091 		return 0;
1092 
1093 	switch (ct_tuple->dst.protonum) {
1094 	case IPPROTO_TCP:
1095 	case IPPROTO_UDP:
1096 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_SRC_PORT)) &&
1097 		    filter_tuple->src.u.tcp.port != ct_tuple->src.u.tcp.port)
1098 			return 0;
1099 
1100 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_DST_PORT)) &&
1101 		    filter_tuple->dst.u.tcp.port != ct_tuple->dst.u.tcp.port)
1102 			return 0;
1103 		break;
1104 	case IPPROTO_ICMP:
1105 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_TYPE)) &&
1106 		    filter_tuple->dst.u.icmp.type != ct_tuple->dst.u.icmp.type)
1107 			return 0;
1108 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_CODE)) &&
1109 		    filter_tuple->dst.u.icmp.code != ct_tuple->dst.u.icmp.code)
1110 			return 0;
1111 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMP_ID)) &&
1112 		    filter_tuple->src.u.icmp.id != ct_tuple->src.u.icmp.id)
1113 			return 0;
1114 		break;
1115 	case IPPROTO_ICMPV6:
1116 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_TYPE)) &&
1117 		    filter_tuple->dst.u.icmp.type != ct_tuple->dst.u.icmp.type)
1118 			return 0;
1119 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_CODE)) &&
1120 		    filter_tuple->dst.u.icmp.code != ct_tuple->dst.u.icmp.code)
1121 			return 0;
1122 		if ((flags & CTA_FILTER_FLAG(CTA_PROTO_ICMPV6_ID)) &&
1123 		    filter_tuple->src.u.icmp.id != ct_tuple->src.u.icmp.id)
1124 			return 0;
1125 		break;
1126 	}
1127 
1128 	return 1;
1129 }
1130 
ctnetlink_filter_match(struct nf_conn * ct,void * data)1131 static int ctnetlink_filter_match(struct nf_conn *ct, void *data)
1132 {
1133 	struct ctnetlink_filter *filter = data;
1134 	struct nf_conntrack_tuple *tuple;
1135 	u32 status;
1136 
1137 	if (filter == NULL)
1138 		goto out;
1139 
1140 	/* Match entries of a given L3 protocol number.
1141 	 * If it is not specified, ie. l3proto == 0,
1142 	 * then match everything.
1143 	 */
1144 	if (filter->family && nf_ct_l3num(ct) != filter->family)
1145 		goto ignore_entry;
1146 
1147 	if (filter->orig_flags) {
1148 		tuple = nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL);
1149 		if (!ctnetlink_filter_match_tuple(&filter->orig, tuple,
1150 						  filter->orig_flags,
1151 						  filter->family))
1152 			goto ignore_entry;
1153 	}
1154 
1155 	if (filter->reply_flags) {
1156 		tuple = nf_ct_tuple(ct, IP_CT_DIR_REPLY);
1157 		if (!ctnetlink_filter_match_tuple(&filter->reply, tuple,
1158 						  filter->reply_flags,
1159 						  filter->family))
1160 			goto ignore_entry;
1161 	}
1162 
1163 #ifdef CONFIG_NF_CONNTRACK_MARK
1164 	if ((READ_ONCE(ct->mark) & filter->mark.mask) != filter->mark.val)
1165 		goto ignore_entry;
1166 #endif
1167 	status = (u32)READ_ONCE(ct->status);
1168 	if ((status & filter->status.mask) != filter->status.val)
1169 		goto ignore_entry;
1170 
1171 out:
1172 	return 1;
1173 
1174 ignore_entry:
1175 	return 0;
1176 }
1177 
1178 static int
ctnetlink_dump_table(struct sk_buff * skb,struct netlink_callback * cb)1179 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1180 {
1181 	unsigned int flags = cb->data ? NLM_F_DUMP_FILTERED : 0;
1182 	struct net *net = sock_net(skb->sk);
1183 	struct nf_conn *ct, *last;
1184 	struct nf_conntrack_tuple_hash *h;
1185 	struct hlist_nulls_node *n;
1186 	struct nf_conn *nf_ct_evict[8];
1187 	int res, i;
1188 	spinlock_t *lockp;
1189 
1190 	last = (struct nf_conn *)cb->args[1];
1191 	i = 0;
1192 
1193 	local_bh_disable();
1194 	for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
1195 restart:
1196 		while (i) {
1197 			i--;
1198 			if (nf_ct_should_gc(nf_ct_evict[i]))
1199 				nf_ct_kill(nf_ct_evict[i]);
1200 			nf_ct_put(nf_ct_evict[i]);
1201 		}
1202 
1203 		lockp = &nf_conntrack_locks[cb->args[0] % CONNTRACK_LOCKS];
1204 		nf_conntrack_lock(lockp);
1205 		if (cb->args[0] >= nf_conntrack_htable_size) {
1206 			spin_unlock(lockp);
1207 			goto out;
1208 		}
1209 		hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[cb->args[0]],
1210 					   hnnode) {
1211 			ct = nf_ct_tuplehash_to_ctrack(h);
1212 			if (nf_ct_is_expired(ct)) {
1213 				/* need to defer nf_ct_kill() until lock is released */
1214 				if (i < ARRAY_SIZE(nf_ct_evict) &&
1215 				    refcount_inc_not_zero(&ct->ct_general.use))
1216 					nf_ct_evict[i++] = ct;
1217 				continue;
1218 			}
1219 
1220 			if (!net_eq(net, nf_ct_net(ct)))
1221 				continue;
1222 
1223 			if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
1224 				continue;
1225 
1226 			if (cb->args[1]) {
1227 				if (ct != last)
1228 					continue;
1229 				cb->args[1] = 0;
1230 			}
1231 			if (!ctnetlink_filter_match(ct, cb->data))
1232 				continue;
1233 
1234 			res =
1235 			ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
1236 					    cb->nlh->nlmsg_seq,
1237 					    NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
1238 					    ct, true, flags);
1239 			if (res < 0) {
1240 				nf_conntrack_get(&ct->ct_general);
1241 				cb->args[1] = (unsigned long)ct;
1242 				spin_unlock(lockp);
1243 				goto out;
1244 			}
1245 		}
1246 		spin_unlock(lockp);
1247 		if (cb->args[1]) {
1248 			cb->args[1] = 0;
1249 			goto restart;
1250 		}
1251 	}
1252 out:
1253 	local_bh_enable();
1254 	if (last) {
1255 		/* nf ct hash resize happened, now clear the leftover. */
1256 		if ((struct nf_conn *)cb->args[1] == last)
1257 			cb->args[1] = 0;
1258 
1259 		nf_ct_put(last);
1260 	}
1261 
1262 	while (i) {
1263 		i--;
1264 		if (nf_ct_should_gc(nf_ct_evict[i]))
1265 			nf_ct_kill(nf_ct_evict[i]);
1266 		nf_ct_put(nf_ct_evict[i]);
1267 	}
1268 
1269 	return skb->len;
1270 }
1271 
ipv4_nlattr_to_tuple(struct nlattr * tb[],struct nf_conntrack_tuple * t,u_int32_t flags)1272 static int ipv4_nlattr_to_tuple(struct nlattr *tb[],
1273 				struct nf_conntrack_tuple *t,
1274 				u_int32_t flags)
1275 {
1276 	if (flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1277 		if (!tb[CTA_IP_V4_SRC])
1278 			return -EINVAL;
1279 
1280 		t->src.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_SRC]);
1281 	}
1282 
1283 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST)) {
1284 		if (!tb[CTA_IP_V4_DST])
1285 			return -EINVAL;
1286 
1287 		t->dst.u3.ip = nla_get_in_addr(tb[CTA_IP_V4_DST]);
1288 	}
1289 
1290 	return 0;
1291 }
1292 
ipv6_nlattr_to_tuple(struct nlattr * tb[],struct nf_conntrack_tuple * t,u_int32_t flags)1293 static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
1294 				struct nf_conntrack_tuple *t,
1295 				u_int32_t flags)
1296 {
1297 	if (flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1298 		if (!tb[CTA_IP_V6_SRC])
1299 			return -EINVAL;
1300 
1301 		t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]);
1302 	}
1303 
1304 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST)) {
1305 		if (!tb[CTA_IP_V6_DST])
1306 			return -EINVAL;
1307 
1308 		t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]);
1309 	}
1310 
1311 	return 0;
1312 }
1313 
ctnetlink_parse_tuple_ip(struct nlattr * attr,struct nf_conntrack_tuple * tuple,u_int32_t flags)1314 static int ctnetlink_parse_tuple_ip(struct nlattr *attr,
1315 				    struct nf_conntrack_tuple *tuple,
1316 				    u_int32_t flags)
1317 {
1318 	struct nlattr *tb[CTA_IP_MAX+1];
1319 	int ret = 0;
1320 
1321 	ret = nla_parse_nested_deprecated(tb, CTA_IP_MAX, attr,
1322 					  cta_ip_nla_policy, NULL);
1323 	if (ret < 0)
1324 		return ret;
1325 
1326 	switch (tuple->src.l3num) {
1327 	case NFPROTO_IPV4:
1328 		ret = ipv4_nlattr_to_tuple(tb, tuple, flags);
1329 		break;
1330 	case NFPROTO_IPV6:
1331 		ret = ipv6_nlattr_to_tuple(tb, tuple, flags);
1332 		break;
1333 	}
1334 
1335 	return ret;
1336 }
1337 
1338 static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
1339 	[CTA_PROTO_NUM]	= { .type = NLA_U8 },
1340 };
1341 
ctnetlink_parse_tuple_proto(struct nlattr * attr,struct nf_conntrack_tuple * tuple,u_int32_t flags)1342 static int ctnetlink_parse_tuple_proto(struct nlattr *attr,
1343 				       struct nf_conntrack_tuple *tuple,
1344 				       u_int32_t flags)
1345 {
1346 	const struct nf_conntrack_l4proto *l4proto;
1347 	struct nlattr *tb[CTA_PROTO_MAX+1];
1348 	int ret = 0;
1349 
1350 	ret = nla_parse_nested_deprecated(tb, CTA_PROTO_MAX, attr,
1351 					  proto_nla_policy, NULL);
1352 	if (ret < 0)
1353 		return ret;
1354 
1355 	if (!(flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)))
1356 		return 0;
1357 
1358 	if (!tb[CTA_PROTO_NUM])
1359 		return -EINVAL;
1360 
1361 	tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
1362 
1363 	rcu_read_lock();
1364 	l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
1365 
1366 	if (likely(l4proto->nlattr_to_tuple)) {
1367 		ret = nla_validate_nested_deprecated(attr, CTA_PROTO_MAX,
1368 						     l4proto->nla_policy,
1369 						     NULL);
1370 		if (ret == 0)
1371 			ret = l4proto->nlattr_to_tuple(tb, tuple, flags);
1372 	}
1373 
1374 	rcu_read_unlock();
1375 
1376 	return ret;
1377 }
1378 
1379 static int
ctnetlink_parse_zone(const struct nlattr * attr,struct nf_conntrack_zone * zone)1380 ctnetlink_parse_zone(const struct nlattr *attr,
1381 		     struct nf_conntrack_zone *zone)
1382 {
1383 	nf_ct_zone_init(zone, NF_CT_DEFAULT_ZONE_ID,
1384 			NF_CT_DEFAULT_ZONE_DIR, 0);
1385 #ifdef CONFIG_NF_CONNTRACK_ZONES
1386 	if (attr)
1387 		zone->id = ntohs(nla_get_be16(attr));
1388 #else
1389 	if (attr)
1390 		return -EOPNOTSUPP;
1391 #endif
1392 	return 0;
1393 }
1394 
1395 static int
ctnetlink_parse_tuple_zone(struct nlattr * attr,enum ctattr_type type,struct nf_conntrack_zone * zone)1396 ctnetlink_parse_tuple_zone(struct nlattr *attr, enum ctattr_type type,
1397 			   struct nf_conntrack_zone *zone)
1398 {
1399 	int ret;
1400 
1401 	if (zone->id != NF_CT_DEFAULT_ZONE_ID)
1402 		return -EINVAL;
1403 
1404 	ret = ctnetlink_parse_zone(attr, zone);
1405 	if (ret < 0)
1406 		return ret;
1407 
1408 	if (type == CTA_TUPLE_REPLY)
1409 		zone->dir = NF_CT_ZONE_DIR_REPL;
1410 	else
1411 		zone->dir = NF_CT_ZONE_DIR_ORIG;
1412 
1413 	return 0;
1414 }
1415 
1416 static const struct nla_policy tuple_nla_policy[CTA_TUPLE_MAX+1] = {
1417 	[CTA_TUPLE_IP]		= { .type = NLA_NESTED },
1418 	[CTA_TUPLE_PROTO]	= { .type = NLA_NESTED },
1419 	[CTA_TUPLE_ZONE]	= { .type = NLA_U16 },
1420 };
1421 
1422 #define CTA_FILTER_F_ALL_CTA_PROTO \
1423   (CTA_FILTER_F_CTA_PROTO_SRC_PORT | \
1424    CTA_FILTER_F_CTA_PROTO_DST_PORT | \
1425    CTA_FILTER_F_CTA_PROTO_ICMP_TYPE | \
1426    CTA_FILTER_F_CTA_PROTO_ICMP_CODE | \
1427    CTA_FILTER_F_CTA_PROTO_ICMP_ID | \
1428    CTA_FILTER_F_CTA_PROTO_ICMPV6_TYPE | \
1429    CTA_FILTER_F_CTA_PROTO_ICMPV6_CODE | \
1430    CTA_FILTER_F_CTA_PROTO_ICMPV6_ID)
1431 
1432 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)1433 ctnetlink_parse_tuple_filter(const struct nlattr * const cda[],
1434 			      struct nf_conntrack_tuple *tuple, u32 type,
1435 			      u_int8_t l3num, struct nf_conntrack_zone *zone,
1436 			      u_int32_t flags)
1437 {
1438 	struct nlattr *tb[CTA_TUPLE_MAX+1];
1439 	int err;
1440 
1441 	memset(tuple, 0, sizeof(*tuple));
1442 
1443 	err = nla_parse_nested_deprecated(tb, CTA_TUPLE_MAX, cda[type],
1444 					  tuple_nla_policy, NULL);
1445 	if (err < 0)
1446 		return err;
1447 
1448 	if (l3num != NFPROTO_IPV4 && l3num != NFPROTO_IPV6)
1449 		return -EOPNOTSUPP;
1450 	tuple->src.l3num = l3num;
1451 
1452 	if (flags & CTA_FILTER_FLAG(CTA_IP_DST) ||
1453 	    flags & CTA_FILTER_FLAG(CTA_IP_SRC)) {
1454 		if (!tb[CTA_TUPLE_IP])
1455 			return -EINVAL;
1456 
1457 		err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple, flags);
1458 		if (err < 0)
1459 			return err;
1460 	}
1461 
1462 	if (flags & CTA_FILTER_FLAG(CTA_PROTO_NUM)) {
1463 		if (!tb[CTA_TUPLE_PROTO])
1464 			return -EINVAL;
1465 
1466 		err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple, flags);
1467 		if (err < 0)
1468 			return err;
1469 	} else if (flags & CTA_FILTER_FLAG(ALL_CTA_PROTO)) {
1470 		/* Can't manage proto flags without a protonum  */
1471 		return -EINVAL;
1472 	}
1473 
1474 	if ((flags & CTA_FILTER_FLAG(CTA_TUPLE_ZONE)) && tb[CTA_TUPLE_ZONE]) {
1475 		if (!zone)
1476 			return -EINVAL;
1477 
1478 		err = ctnetlink_parse_tuple_zone(tb[CTA_TUPLE_ZONE],
1479 						 type, zone);
1480 		if (err < 0)
1481 			return err;
1482 	}
1483 
1484 	/* orig and expect tuples get DIR_ORIGINAL */
1485 	if (type == CTA_TUPLE_REPLY)
1486 		tuple->dst.dir = IP_CT_DIR_REPLY;
1487 	else
1488 		tuple->dst.dir = IP_CT_DIR_ORIGINAL;
1489 
1490 	return 0;
1491 }
1492 
1493 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)1494 ctnetlink_parse_tuple(const struct nlattr * const cda[],
1495 		      struct nf_conntrack_tuple *tuple, u32 type,
1496 		      u_int8_t l3num, struct nf_conntrack_zone *zone)
1497 {
1498 	return ctnetlink_parse_tuple_filter(cda, tuple, type, l3num, zone,
1499 					    CTA_FILTER_FLAG(ALL));
1500 }
1501 
1502 static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = {
1503 	[CTA_HELP_NAME]		= { .type = NLA_NUL_STRING,
1504 				    .len = NF_CT_HELPER_NAME_LEN - 1 },
1505 };
1506 
ctnetlink_parse_help(const struct nlattr * attr,char ** helper_name,struct nlattr ** helpinfo)1507 static int ctnetlink_parse_help(const struct nlattr *attr, char **helper_name,
1508 				struct nlattr **helpinfo)
1509 {
1510 	int err;
1511 	struct nlattr *tb[CTA_HELP_MAX+1];
1512 
1513 	err = nla_parse_nested_deprecated(tb, CTA_HELP_MAX, attr,
1514 					  help_nla_policy, NULL);
1515 	if (err < 0)
1516 		return err;
1517 
1518 	if (!tb[CTA_HELP_NAME])
1519 		return -EINVAL;
1520 
1521 	*helper_name = nla_data(tb[CTA_HELP_NAME]);
1522 
1523 	if (tb[CTA_HELP_INFO])
1524 		*helpinfo = tb[CTA_HELP_INFO];
1525 
1526 	return 0;
1527 }
1528 
1529 static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
1530 	[CTA_TUPLE_ORIG]	= { .type = NLA_NESTED },
1531 	[CTA_TUPLE_REPLY]	= { .type = NLA_NESTED },
1532 	[CTA_STATUS] 		= { .type = NLA_U32 },
1533 	[CTA_PROTOINFO]		= { .type = NLA_NESTED },
1534 	[CTA_HELP]		= { .type = NLA_NESTED },
1535 	[CTA_NAT_SRC]		= { .type = NLA_NESTED },
1536 	[CTA_TIMEOUT] 		= { .type = NLA_U32 },
1537 	[CTA_MARK]		= { .type = NLA_U32 },
1538 	[CTA_ID]		= { .type = NLA_U32 },
1539 	[CTA_NAT_DST]		= { .type = NLA_NESTED },
1540 	[CTA_TUPLE_MASTER]	= { .type = NLA_NESTED },
1541 	[CTA_NAT_SEQ_ADJ_ORIG]  = { .type = NLA_NESTED },
1542 	[CTA_NAT_SEQ_ADJ_REPLY] = { .type = NLA_NESTED },
1543 	[CTA_ZONE]		= { .type = NLA_U16 },
1544 	[CTA_MARK_MASK]		= { .type = NLA_U32 },
1545 	[CTA_LABELS]		= { .type = NLA_BINARY,
1546 				    .len = NF_CT_LABELS_MAX_SIZE },
1547 	[CTA_LABELS_MASK]	= { .type = NLA_BINARY,
1548 				    .len = NF_CT_LABELS_MAX_SIZE },
1549 	[CTA_FILTER]		= { .type = NLA_NESTED },
1550 	[CTA_STATUS_MASK]	= { .type = NLA_U32 },
1551 };
1552 
ctnetlink_flush_iterate(struct nf_conn * ct,void * data)1553 static int ctnetlink_flush_iterate(struct nf_conn *ct, void *data)
1554 {
1555 	return ctnetlink_filter_match(ct, data);
1556 }
1557 
ctnetlink_flush_conntrack(struct net * net,const struct nlattr * const cda[],u32 portid,int report,u8 family)1558 static int ctnetlink_flush_conntrack(struct net *net,
1559 				     const struct nlattr * const cda[],
1560 				     u32 portid, int report, u8 family)
1561 {
1562 	struct ctnetlink_filter *filter = NULL;
1563 	struct nf_ct_iter_data iter = {
1564 		.net		= net,
1565 		.portid		= portid,
1566 		.report		= report,
1567 	};
1568 
1569 	if (ctnetlink_needs_filter(family, cda)) {
1570 		if (cda[CTA_FILTER])
1571 			return -EOPNOTSUPP;
1572 
1573 		filter = ctnetlink_alloc_filter(cda, family);
1574 		if (IS_ERR(filter))
1575 			return PTR_ERR(filter);
1576 
1577 		iter.data = filter;
1578 	}
1579 
1580 	nf_ct_iterate_cleanup_net(ctnetlink_flush_iterate, &iter);
1581 	kfree(filter);
1582 
1583 	return 0;
1584 }
1585 
ctnetlink_del_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1586 static int ctnetlink_del_conntrack(struct sk_buff *skb,
1587 				   const struct nfnl_info *info,
1588 				   const struct nlattr * const cda[])
1589 {
1590 	u8 family = info->nfmsg->nfgen_family;
1591 	struct nf_conntrack_tuple_hash *h;
1592 	struct nf_conntrack_tuple tuple;
1593 	struct nf_conntrack_zone zone;
1594 	struct nf_conn *ct;
1595 	int err;
1596 
1597 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1598 	if (err < 0)
1599 		return err;
1600 
1601 	if (cda[CTA_TUPLE_ORIG])
1602 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG,
1603 					    family, &zone);
1604 	else if (cda[CTA_TUPLE_REPLY])
1605 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY,
1606 					    family, &zone);
1607 	else {
1608 		u_int8_t u3 = info->nfmsg->version ? family : AF_UNSPEC;
1609 
1610 		return ctnetlink_flush_conntrack(info->net, cda,
1611 						 NETLINK_CB(skb).portid,
1612 						 nlmsg_report(info->nlh), u3);
1613 	}
1614 
1615 	if (err < 0)
1616 		return err;
1617 
1618 	h = nf_conntrack_find_get(info->net, &zone, &tuple);
1619 	if (!h)
1620 		return -ENOENT;
1621 
1622 	ct = nf_ct_tuplehash_to_ctrack(h);
1623 
1624 	if (cda[CTA_ID]) {
1625 		__be32 id = nla_get_be32(cda[CTA_ID]);
1626 
1627 		if (id != (__force __be32)nf_ct_get_id(ct)) {
1628 			nf_ct_put(ct);
1629 			return -ENOENT;
1630 		}
1631 	}
1632 
1633 	nf_ct_delete(ct, NETLINK_CB(skb).portid, nlmsg_report(info->nlh));
1634 	nf_ct_put(ct);
1635 
1636 	return 0;
1637 }
1638 
ctnetlink_get_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1639 static int ctnetlink_get_conntrack(struct sk_buff *skb,
1640 				   const struct nfnl_info *info,
1641 				   const struct nlattr * const cda[])
1642 {
1643 	u_int8_t u3 = info->nfmsg->nfgen_family;
1644 	struct nf_conntrack_tuple_hash *h;
1645 	struct nf_conntrack_tuple tuple;
1646 	struct nf_conntrack_zone zone;
1647 	struct sk_buff *skb2;
1648 	struct nf_conn *ct;
1649 	int err;
1650 
1651 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1652 		struct netlink_dump_control c = {
1653 			.start = ctnetlink_start,
1654 			.dump = ctnetlink_dump_table,
1655 			.done = ctnetlink_done,
1656 			.data = (void *)cda,
1657 		};
1658 
1659 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1660 	}
1661 
1662 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1663 	if (err < 0)
1664 		return err;
1665 
1666 	if (cda[CTA_TUPLE_ORIG])
1667 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG,
1668 					    u3, &zone);
1669 	else if (cda[CTA_TUPLE_REPLY])
1670 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY,
1671 					    u3, &zone);
1672 	else
1673 		return -EINVAL;
1674 
1675 	if (err < 0)
1676 		return err;
1677 
1678 	h = nf_conntrack_find_get(info->net, &zone, &tuple);
1679 	if (!h)
1680 		return -ENOENT;
1681 
1682 	ct = nf_ct_tuplehash_to_ctrack(h);
1683 
1684 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1685 	if (!skb2) {
1686 		nf_ct_put(ct);
1687 		return -ENOMEM;
1688 	}
1689 
1690 	err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).portid,
1691 				  info->nlh->nlmsg_seq,
1692 				  NFNL_MSG_TYPE(info->nlh->nlmsg_type), ct,
1693 				  true, 0);
1694 	nf_ct_put(ct);
1695 	if (err <= 0) {
1696 		kfree_skb(skb2);
1697 		return -ENOMEM;
1698 	}
1699 
1700 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
1701 }
1702 
ctnetlink_done_list(struct netlink_callback * cb)1703 static int ctnetlink_done_list(struct netlink_callback *cb)
1704 {
1705 	struct ctnetlink_list_dump_ctx *ctx = (void *)cb->ctx;
1706 
1707 	if (ctx->last)
1708 		nf_ct_put(ctx->last);
1709 
1710 	return 0;
1711 }
1712 
1713 #ifdef CONFIG_NF_CONNTRACK_EVENTS
ctnetlink_dump_one_entry(struct sk_buff * skb,struct netlink_callback * cb,struct nf_conn * ct,bool dying)1714 static int ctnetlink_dump_one_entry(struct sk_buff *skb,
1715 				    struct netlink_callback *cb,
1716 				    struct nf_conn *ct,
1717 				    bool dying)
1718 {
1719 	struct ctnetlink_list_dump_ctx *ctx = (void *)cb->ctx;
1720 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1721 	u8 l3proto = nfmsg->nfgen_family;
1722 	int res;
1723 
1724 	if (l3proto && nf_ct_l3num(ct) != l3proto)
1725 		return 0;
1726 
1727 	if (ctx->last) {
1728 		if (ct != ctx->last)
1729 			return 0;
1730 
1731 		ctx->last = NULL;
1732 	}
1733 
1734 	/* We can't dump extension info for the unconfirmed
1735 	 * list because unconfirmed conntracks can have
1736 	 * ct->ext reallocated (and thus freed).
1737 	 *
1738 	 * In the dying list case ct->ext can't be free'd
1739 	 * until after we drop pcpu->lock.
1740 	 */
1741 	res = ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
1742 				  cb->nlh->nlmsg_seq,
1743 				  NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
1744 				  ct, dying, 0);
1745 	if (res < 0) {
1746 		if (!refcount_inc_not_zero(&ct->ct_general.use))
1747 			return 0;
1748 
1749 		ctx->last = ct;
1750 	}
1751 
1752 	return res;
1753 }
1754 #endif
1755 
1756 static int
ctnetlink_dump_unconfirmed(struct sk_buff * skb,struct netlink_callback * cb)1757 ctnetlink_dump_unconfirmed(struct sk_buff *skb, struct netlink_callback *cb)
1758 {
1759 	return 0;
1760 }
1761 
1762 static int
ctnetlink_dump_dying(struct sk_buff * skb,struct netlink_callback * cb)1763 ctnetlink_dump_dying(struct sk_buff *skb, struct netlink_callback *cb)
1764 {
1765 	struct ctnetlink_list_dump_ctx *ctx = (void *)cb->ctx;
1766 	struct nf_conn *last = ctx->last;
1767 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1768 	const struct net *net = sock_net(skb->sk);
1769 	struct nf_conntrack_net_ecache *ecache_net;
1770 	struct nf_conntrack_tuple_hash *h;
1771 	struct hlist_nulls_node *n;
1772 #endif
1773 
1774 	if (ctx->done)
1775 		return 0;
1776 
1777 	ctx->last = NULL;
1778 
1779 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1780 	ecache_net = nf_conn_pernet_ecache(net);
1781 	spin_lock_bh(&ecache_net->dying_lock);
1782 
1783 	hlist_nulls_for_each_entry(h, n, &ecache_net->dying_list, hnnode) {
1784 		struct nf_conn *ct;
1785 		int res;
1786 
1787 		ct = nf_ct_tuplehash_to_ctrack(h);
1788 		if (last && last != ct)
1789 			continue;
1790 
1791 		res = ctnetlink_dump_one_entry(skb, cb, ct, true);
1792 		if (res < 0) {
1793 			spin_unlock_bh(&ecache_net->dying_lock);
1794 			nf_ct_put(last);
1795 			return skb->len;
1796 		}
1797 
1798 		nf_ct_put(last);
1799 		last = NULL;
1800 	}
1801 
1802 	spin_unlock_bh(&ecache_net->dying_lock);
1803 #endif
1804 	ctx->done = true;
1805 	nf_ct_put(last);
1806 
1807 	return skb->len;
1808 }
1809 
ctnetlink_get_ct_dying(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1810 static int ctnetlink_get_ct_dying(struct sk_buff *skb,
1811 				  const struct nfnl_info *info,
1812 				  const struct nlattr * const cda[])
1813 {
1814 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1815 		struct netlink_dump_control c = {
1816 			.dump = ctnetlink_dump_dying,
1817 			.done = ctnetlink_done_list,
1818 		};
1819 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1820 	}
1821 
1822 	return -EOPNOTSUPP;
1823 }
1824 
ctnetlink_get_ct_unconfirmed(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])1825 static int ctnetlink_get_ct_unconfirmed(struct sk_buff *skb,
1826 					const struct nfnl_info *info,
1827 					const struct nlattr * const cda[])
1828 {
1829 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
1830 		struct netlink_dump_control c = {
1831 			.dump = ctnetlink_dump_unconfirmed,
1832 			.done = ctnetlink_done_list,
1833 		};
1834 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
1835 	}
1836 
1837 	return -EOPNOTSUPP;
1838 }
1839 
1840 #if IS_ENABLED(CONFIG_NF_NAT)
1841 static int
ctnetlink_parse_nat_setup(struct nf_conn * ct,enum nf_nat_manip_type manip,const struct nlattr * attr)1842 ctnetlink_parse_nat_setup(struct nf_conn *ct,
1843 			  enum nf_nat_manip_type manip,
1844 			  const struct nlattr *attr)
1845 	__must_hold(RCU)
1846 {
1847 	const struct nf_nat_hook *nat_hook;
1848 	int err;
1849 
1850 	nat_hook = rcu_dereference(nf_nat_hook);
1851 	if (!nat_hook) {
1852 #ifdef CONFIG_MODULES
1853 		rcu_read_unlock();
1854 		nfnl_unlock(NFNL_SUBSYS_CTNETLINK);
1855 		if (request_module("nf-nat") < 0) {
1856 			nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1857 			rcu_read_lock();
1858 			return -EOPNOTSUPP;
1859 		}
1860 		nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1861 		rcu_read_lock();
1862 		nat_hook = rcu_dereference(nf_nat_hook);
1863 		if (nat_hook)
1864 			return -EAGAIN;
1865 #endif
1866 		return -EOPNOTSUPP;
1867 	}
1868 
1869 	err = nat_hook->parse_nat_setup(ct, manip, attr);
1870 	if (err == -EAGAIN) {
1871 #ifdef CONFIG_MODULES
1872 		rcu_read_unlock();
1873 		nfnl_unlock(NFNL_SUBSYS_CTNETLINK);
1874 		if (request_module("nf-nat-%u", nf_ct_l3num(ct)) < 0) {
1875 			nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1876 			rcu_read_lock();
1877 			return -EOPNOTSUPP;
1878 		}
1879 		nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1880 		rcu_read_lock();
1881 #else
1882 		err = -EOPNOTSUPP;
1883 #endif
1884 	}
1885 	return err;
1886 }
1887 #endif
1888 
1889 static int
ctnetlink_change_status(struct nf_conn * ct,const struct nlattr * const cda[])1890 ctnetlink_change_status(struct nf_conn *ct, const struct nlattr * const cda[])
1891 {
1892 	return nf_ct_change_status_common(ct, ntohl(nla_get_be32(cda[CTA_STATUS])));
1893 }
1894 
1895 static int
ctnetlink_setup_nat(struct nf_conn * ct,const struct nlattr * const cda[])1896 ctnetlink_setup_nat(struct nf_conn *ct, const struct nlattr * const cda[])
1897 {
1898 #if IS_ENABLED(CONFIG_NF_NAT)
1899 	int ret;
1900 
1901 	if (!cda[CTA_NAT_DST] && !cda[CTA_NAT_SRC])
1902 		return 0;
1903 
1904 	ret = ctnetlink_parse_nat_setup(ct, NF_NAT_MANIP_DST,
1905 					cda[CTA_NAT_DST]);
1906 	if (ret < 0)
1907 		return ret;
1908 
1909 	return ctnetlink_parse_nat_setup(ct, NF_NAT_MANIP_SRC,
1910 					 cda[CTA_NAT_SRC]);
1911 #else
1912 	if (!cda[CTA_NAT_DST] && !cda[CTA_NAT_SRC])
1913 		return 0;
1914 	return -EOPNOTSUPP;
1915 #endif
1916 }
1917 
ctnetlink_change_helper(struct nf_conn * ct,const struct nlattr * const cda[])1918 static int ctnetlink_change_helper(struct nf_conn *ct,
1919 				   const struct nlattr * const cda[])
1920 {
1921 	struct nf_conntrack_helper *helper;
1922 	struct nf_conn_help *help = nfct_help(ct);
1923 	char *helpname = NULL;
1924 	struct nlattr *helpinfo = NULL;
1925 	int err;
1926 
1927 	err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
1928 	if (err < 0)
1929 		return err;
1930 
1931 	/* don't change helper of sibling connections */
1932 	if (ct->master) {
1933 		/* If we try to change the helper to the same thing twice,
1934 		 * treat the second attempt as a no-op instead of returning
1935 		 * an error.
1936 		 */
1937 		err = -EBUSY;
1938 		if (help) {
1939 			rcu_read_lock();
1940 			helper = rcu_dereference(help->helper);
1941 			if (helper && !strcmp(helper->name, helpname))
1942 				err = 0;
1943 			rcu_read_unlock();
1944 		}
1945 
1946 		return err;
1947 	}
1948 
1949 	if (!strcmp(helpname, "")) {
1950 		if (help && help->helper) {
1951 			/* we had a helper before ... */
1952 			nf_ct_remove_expectations(ct);
1953 			RCU_INIT_POINTER(help->helper, NULL);
1954 		}
1955 
1956 		return 0;
1957 	}
1958 
1959 	rcu_read_lock();
1960 	helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
1961 					    nf_ct_protonum(ct));
1962 	if (helper == NULL) {
1963 		rcu_read_unlock();
1964 		return -EOPNOTSUPP;
1965 	}
1966 
1967 	if (help) {
1968 		if (rcu_access_pointer(help->helper) == helper) {
1969 			/* update private helper data if allowed. */
1970 			if (helper->from_nlattr)
1971 				helper->from_nlattr(helpinfo, ct);
1972 			err = 0;
1973 		} else
1974 			err = -EBUSY;
1975 	} else {
1976 		/* we cannot set a helper for an existing conntrack */
1977 		err = -EOPNOTSUPP;
1978 	}
1979 
1980 	rcu_read_unlock();
1981 	return err;
1982 }
1983 
ctnetlink_change_timeout(struct nf_conn * ct,const struct nlattr * const cda[])1984 static int ctnetlink_change_timeout(struct nf_conn *ct,
1985 				    const struct nlattr * const cda[])
1986 {
1987 	return __nf_ct_change_timeout(ct, (u64)ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ);
1988 }
1989 
1990 #if defined(CONFIG_NF_CONNTRACK_MARK)
ctnetlink_change_mark(struct nf_conn * ct,const struct nlattr * const cda[])1991 static void ctnetlink_change_mark(struct nf_conn *ct,
1992 				    const struct nlattr * const cda[])
1993 {
1994 	u32 mark, newmark, mask = 0;
1995 
1996 	if (cda[CTA_MARK_MASK])
1997 		mask = ~ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
1998 
1999 	mark = ntohl(nla_get_be32(cda[CTA_MARK]));
2000 	newmark = (READ_ONCE(ct->mark) & mask) ^ mark;
2001 	if (newmark != READ_ONCE(ct->mark))
2002 		WRITE_ONCE(ct->mark, newmark);
2003 }
2004 #endif
2005 
2006 static const struct nla_policy protoinfo_policy[CTA_PROTOINFO_MAX+1] = {
2007 	[CTA_PROTOINFO_TCP]	= { .type = NLA_NESTED },
2008 	[CTA_PROTOINFO_DCCP]	= { .type = NLA_NESTED },
2009 	[CTA_PROTOINFO_SCTP]	= { .type = NLA_NESTED },
2010 };
2011 
ctnetlink_change_protoinfo(struct nf_conn * ct,const struct nlattr * const cda[])2012 static int ctnetlink_change_protoinfo(struct nf_conn *ct,
2013 				      const struct nlattr * const cda[])
2014 {
2015 	const struct nlattr *attr = cda[CTA_PROTOINFO];
2016 	const struct nf_conntrack_l4proto *l4proto;
2017 	struct nlattr *tb[CTA_PROTOINFO_MAX+1];
2018 	int err = 0;
2019 
2020 	err = nla_parse_nested_deprecated(tb, CTA_PROTOINFO_MAX, attr,
2021 					  protoinfo_policy, NULL);
2022 	if (err < 0)
2023 		return err;
2024 
2025 	l4proto = nf_ct_l4proto_find(nf_ct_protonum(ct));
2026 	if (l4proto->from_nlattr)
2027 		err = l4proto->from_nlattr(tb, ct);
2028 
2029 	return err;
2030 }
2031 
2032 static const struct nla_policy seqadj_policy[CTA_SEQADJ_MAX+1] = {
2033 	[CTA_SEQADJ_CORRECTION_POS]	= { .type = NLA_U32 },
2034 	[CTA_SEQADJ_OFFSET_BEFORE]	= { .type = NLA_U32 },
2035 	[CTA_SEQADJ_OFFSET_AFTER]	= { .type = NLA_U32 },
2036 };
2037 
change_seq_adj(struct nf_ct_seqadj * seq,const struct nlattr * const attr)2038 static int change_seq_adj(struct nf_ct_seqadj *seq,
2039 			  const struct nlattr * const attr)
2040 {
2041 	int err;
2042 	struct nlattr *cda[CTA_SEQADJ_MAX+1];
2043 
2044 	err = nla_parse_nested_deprecated(cda, CTA_SEQADJ_MAX, attr,
2045 					  seqadj_policy, NULL);
2046 	if (err < 0)
2047 		return err;
2048 
2049 	if (!cda[CTA_SEQADJ_CORRECTION_POS])
2050 		return -EINVAL;
2051 
2052 	seq->correction_pos =
2053 		ntohl(nla_get_be32(cda[CTA_SEQADJ_CORRECTION_POS]));
2054 
2055 	if (!cda[CTA_SEQADJ_OFFSET_BEFORE])
2056 		return -EINVAL;
2057 
2058 	seq->offset_before =
2059 		ntohl(nla_get_be32(cda[CTA_SEQADJ_OFFSET_BEFORE]));
2060 
2061 	if (!cda[CTA_SEQADJ_OFFSET_AFTER])
2062 		return -EINVAL;
2063 
2064 	seq->offset_after =
2065 		ntohl(nla_get_be32(cda[CTA_SEQADJ_OFFSET_AFTER]));
2066 
2067 	return 0;
2068 }
2069 
2070 static int
ctnetlink_change_seq_adj(struct nf_conn * ct,const struct nlattr * const cda[])2071 ctnetlink_change_seq_adj(struct nf_conn *ct,
2072 			 const struct nlattr * const cda[])
2073 {
2074 	struct nf_conn_seqadj *seqadj = nfct_seqadj(ct);
2075 	int ret = 0;
2076 
2077 	if (!seqadj)
2078 		return 0;
2079 
2080 	spin_lock_bh(&ct->lock);
2081 	if (cda[CTA_SEQ_ADJ_ORIG]) {
2082 		ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_ORIGINAL],
2083 				     cda[CTA_SEQ_ADJ_ORIG]);
2084 		if (ret < 0)
2085 			goto err;
2086 
2087 		set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
2088 	}
2089 
2090 	if (cda[CTA_SEQ_ADJ_REPLY]) {
2091 		ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_REPLY],
2092 				     cda[CTA_SEQ_ADJ_REPLY]);
2093 		if (ret < 0)
2094 			goto err;
2095 
2096 		set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
2097 	}
2098 
2099 	spin_unlock_bh(&ct->lock);
2100 	return 0;
2101 err:
2102 	spin_unlock_bh(&ct->lock);
2103 	return ret;
2104 }
2105 
2106 static const struct nla_policy synproxy_policy[CTA_SYNPROXY_MAX + 1] = {
2107 	[CTA_SYNPROXY_ISN]	= { .type = NLA_U32 },
2108 	[CTA_SYNPROXY_ITS]	= { .type = NLA_U32 },
2109 	[CTA_SYNPROXY_TSOFF]	= { .type = NLA_U32 },
2110 };
2111 
ctnetlink_change_synproxy(struct nf_conn * ct,const struct nlattr * const cda[])2112 static int ctnetlink_change_synproxy(struct nf_conn *ct,
2113 				     const struct nlattr * const cda[])
2114 {
2115 	struct nf_conn_synproxy *synproxy = nfct_synproxy(ct);
2116 	struct nlattr *tb[CTA_SYNPROXY_MAX + 1];
2117 	int err;
2118 
2119 	if (!synproxy)
2120 		return 0;
2121 
2122 	err = nla_parse_nested_deprecated(tb, CTA_SYNPROXY_MAX,
2123 					  cda[CTA_SYNPROXY], synproxy_policy,
2124 					  NULL);
2125 	if (err < 0)
2126 		return err;
2127 
2128 	if (!tb[CTA_SYNPROXY_ISN] ||
2129 	    !tb[CTA_SYNPROXY_ITS] ||
2130 	    !tb[CTA_SYNPROXY_TSOFF])
2131 		return -EINVAL;
2132 
2133 	synproxy->isn = ntohl(nla_get_be32(tb[CTA_SYNPROXY_ISN]));
2134 	synproxy->its = ntohl(nla_get_be32(tb[CTA_SYNPROXY_ITS]));
2135 	synproxy->tsoff = ntohl(nla_get_be32(tb[CTA_SYNPROXY_TSOFF]));
2136 
2137 	return 0;
2138 }
2139 
2140 static int
ctnetlink_attach_labels(struct nf_conn * ct,const struct nlattr * const cda[])2141 ctnetlink_attach_labels(struct nf_conn *ct, const struct nlattr * const cda[])
2142 {
2143 #ifdef CONFIG_NF_CONNTRACK_LABELS
2144 	size_t len = nla_len(cda[CTA_LABELS]);
2145 	const void *mask = cda[CTA_LABELS_MASK];
2146 
2147 	if (len & (sizeof(u32)-1)) /* must be multiple of u32 */
2148 		return -EINVAL;
2149 
2150 	if (mask) {
2151 		if (nla_len(cda[CTA_LABELS_MASK]) == 0 ||
2152 		    nla_len(cda[CTA_LABELS_MASK]) != len)
2153 			return -EINVAL;
2154 		mask = nla_data(cda[CTA_LABELS_MASK]);
2155 	}
2156 
2157 	len /= sizeof(u32);
2158 
2159 	return nf_connlabels_replace(ct, nla_data(cda[CTA_LABELS]), mask, len);
2160 #else
2161 	return -EOPNOTSUPP;
2162 #endif
2163 }
2164 
2165 static int
ctnetlink_change_conntrack(struct nf_conn * ct,const struct nlattr * const cda[])2166 ctnetlink_change_conntrack(struct nf_conn *ct,
2167 			   const struct nlattr * const cda[])
2168 {
2169 	int err;
2170 
2171 	/* only allow NAT changes and master assignation for new conntracks */
2172 	if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST] || cda[CTA_TUPLE_MASTER])
2173 		return -EOPNOTSUPP;
2174 
2175 	if (cda[CTA_HELP]) {
2176 		err = ctnetlink_change_helper(ct, cda);
2177 		if (err < 0)
2178 			return err;
2179 	}
2180 
2181 	if (cda[CTA_TIMEOUT]) {
2182 		err = ctnetlink_change_timeout(ct, cda);
2183 		if (err < 0)
2184 			return err;
2185 	}
2186 
2187 	if (cda[CTA_STATUS]) {
2188 		err = ctnetlink_change_status(ct, cda);
2189 		if (err < 0)
2190 			return err;
2191 	}
2192 
2193 	if (cda[CTA_PROTOINFO]) {
2194 		err = ctnetlink_change_protoinfo(ct, cda);
2195 		if (err < 0)
2196 			return err;
2197 	}
2198 
2199 #if defined(CONFIG_NF_CONNTRACK_MARK)
2200 	if (cda[CTA_MARK])
2201 		ctnetlink_change_mark(ct, cda);
2202 #endif
2203 
2204 	if (cda[CTA_SEQ_ADJ_ORIG] || cda[CTA_SEQ_ADJ_REPLY]) {
2205 		err = ctnetlink_change_seq_adj(ct, cda);
2206 		if (err < 0)
2207 			return err;
2208 	}
2209 
2210 	if (cda[CTA_SYNPROXY]) {
2211 		err = ctnetlink_change_synproxy(ct, cda);
2212 		if (err < 0)
2213 			return err;
2214 	}
2215 
2216 	if (cda[CTA_LABELS]) {
2217 		err = ctnetlink_attach_labels(ct, cda);
2218 		if (err < 0)
2219 			return err;
2220 	}
2221 
2222 	return 0;
2223 }
2224 
2225 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)2226 ctnetlink_create_conntrack(struct net *net,
2227 			   const struct nf_conntrack_zone *zone,
2228 			   const struct nlattr * const cda[],
2229 			   struct nf_conntrack_tuple *otuple,
2230 			   struct nf_conntrack_tuple *rtuple,
2231 			   u8 u3)
2232 {
2233 	struct nf_conn *ct;
2234 	int err = -EINVAL;
2235 	struct nf_conntrack_helper *helper;
2236 	struct nf_conn_tstamp *tstamp;
2237 	u64 timeout;
2238 
2239 	ct = nf_conntrack_alloc(net, zone, otuple, rtuple, GFP_ATOMIC);
2240 	if (IS_ERR(ct))
2241 		return ERR_PTR(-ENOMEM);
2242 
2243 	if (!cda[CTA_TIMEOUT])
2244 		goto err1;
2245 
2246 	rcu_read_lock();
2247  	if (cda[CTA_HELP]) {
2248 		char *helpname = NULL;
2249 		struct nlattr *helpinfo = NULL;
2250 
2251 		err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
2252  		if (err < 0)
2253 			goto err2;
2254 
2255 		helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
2256 						    nf_ct_protonum(ct));
2257 		if (helper == NULL) {
2258 			rcu_read_unlock();
2259 #ifdef CONFIG_MODULES
2260 			if (request_module("nfct-helper-%s", helpname) < 0) {
2261 				err = -EOPNOTSUPP;
2262 				goto err1;
2263 			}
2264 
2265 			rcu_read_lock();
2266 			helper = __nf_conntrack_helper_find(helpname,
2267 							    nf_ct_l3num(ct),
2268 							    nf_ct_protonum(ct));
2269 			if (helper) {
2270 				err = -EAGAIN;
2271 				goto err2;
2272 			}
2273 			rcu_read_unlock();
2274 #endif
2275 			err = -EOPNOTSUPP;
2276 			goto err1;
2277 		} else {
2278 			struct nf_conn_help *help;
2279 
2280 			help = nf_ct_helper_ext_add(ct, GFP_ATOMIC);
2281 			if (help == NULL) {
2282 				err = -ENOMEM;
2283 				goto err2;
2284 			}
2285 			/* set private helper data if allowed. */
2286 			if (helper->from_nlattr)
2287 				helper->from_nlattr(helpinfo, ct);
2288 
2289 			/* disable helper auto-assignment for this entry */
2290 			ct->status |= IPS_HELPER;
2291 			RCU_INIT_POINTER(help->helper, helper);
2292 		}
2293 	}
2294 
2295 	err = ctnetlink_setup_nat(ct, cda);
2296 	if (err < 0)
2297 		goto err2;
2298 
2299 	nf_ct_acct_ext_add(ct, GFP_ATOMIC);
2300 	nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
2301 	nf_ct_ecache_ext_add(ct, 0, 0, GFP_ATOMIC);
2302 	nf_ct_labels_ext_add(ct);
2303 	nfct_seqadj_ext_add(ct);
2304 	nfct_synproxy_ext_add(ct);
2305 
2306 	/* we must add conntrack extensions before confirmation. */
2307 	ct->status |= IPS_CONFIRMED;
2308 
2309 	timeout = (u64)ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ;
2310 	__nf_ct_set_timeout(ct, timeout);
2311 
2312 	if (cda[CTA_STATUS]) {
2313 		err = ctnetlink_change_status(ct, cda);
2314 		if (err < 0)
2315 			goto err2;
2316 	}
2317 
2318 	if (cda[CTA_SEQ_ADJ_ORIG] || cda[CTA_SEQ_ADJ_REPLY]) {
2319 		err = ctnetlink_change_seq_adj(ct, cda);
2320 		if (err < 0)
2321 			goto err2;
2322 	}
2323 
2324 	memset(&ct->proto, 0, sizeof(ct->proto));
2325 	if (cda[CTA_PROTOINFO]) {
2326 		err = ctnetlink_change_protoinfo(ct, cda);
2327 		if (err < 0)
2328 			goto err2;
2329 	}
2330 
2331 	if (cda[CTA_SYNPROXY]) {
2332 		err = ctnetlink_change_synproxy(ct, cda);
2333 		if (err < 0)
2334 			goto err2;
2335 	}
2336 
2337 #if defined(CONFIG_NF_CONNTRACK_MARK)
2338 	if (cda[CTA_MARK])
2339 		ctnetlink_change_mark(ct, cda);
2340 #endif
2341 
2342 	/* setup master conntrack: this is a confirmed expectation */
2343 	if (cda[CTA_TUPLE_MASTER]) {
2344 		struct nf_conntrack_tuple master;
2345 		struct nf_conntrack_tuple_hash *master_h;
2346 		struct nf_conn *master_ct;
2347 
2348 		err = ctnetlink_parse_tuple(cda, &master, CTA_TUPLE_MASTER,
2349 					    u3, NULL);
2350 		if (err < 0)
2351 			goto err2;
2352 
2353 		master_h = nf_conntrack_find_get(net, zone, &master);
2354 		if (master_h == NULL) {
2355 			err = -ENOENT;
2356 			goto err2;
2357 		}
2358 		master_ct = nf_ct_tuplehash_to_ctrack(master_h);
2359 		__set_bit(IPS_EXPECTED_BIT, &ct->status);
2360 		ct->master = master_ct;
2361 	}
2362 	tstamp = nf_conn_tstamp_find(ct);
2363 	if (tstamp)
2364 		tstamp->start = ktime_get_real_ns();
2365 
2366 	err = nf_conntrack_hash_check_insert(ct);
2367 	if (err < 0)
2368 		goto err3;
2369 
2370 	rcu_read_unlock();
2371 
2372 	return ct;
2373 
2374 err3:
2375 	if (ct->master)
2376 		nf_ct_put(ct->master);
2377 err2:
2378 	rcu_read_unlock();
2379 err1:
2380 	nf_conntrack_free(ct);
2381 	return ERR_PTR(err);
2382 }
2383 
ctnetlink_new_conntrack(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2384 static int ctnetlink_new_conntrack(struct sk_buff *skb,
2385 				   const struct nfnl_info *info,
2386 				   const struct nlattr * const cda[])
2387 {
2388 	struct nf_conntrack_tuple otuple, rtuple;
2389 	struct nf_conntrack_tuple_hash *h = NULL;
2390 	u_int8_t u3 = info->nfmsg->nfgen_family;
2391 	struct nf_conntrack_zone zone;
2392 	struct nf_conn *ct;
2393 	int err;
2394 
2395 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
2396 	if (err < 0)
2397 		return err;
2398 
2399 	if (cda[CTA_TUPLE_ORIG]) {
2400 		err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG,
2401 					    u3, &zone);
2402 		if (err < 0)
2403 			return err;
2404 	}
2405 
2406 	if (cda[CTA_TUPLE_REPLY]) {
2407 		err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY,
2408 					    u3, &zone);
2409 		if (err < 0)
2410 			return err;
2411 	}
2412 
2413 	if (cda[CTA_TUPLE_ORIG])
2414 		h = nf_conntrack_find_get(info->net, &zone, &otuple);
2415 	else if (cda[CTA_TUPLE_REPLY])
2416 		h = nf_conntrack_find_get(info->net, &zone, &rtuple);
2417 
2418 	if (h == NULL) {
2419 		err = -ENOENT;
2420 		if (info->nlh->nlmsg_flags & NLM_F_CREATE) {
2421 			enum ip_conntrack_events events;
2422 
2423 			if (!cda[CTA_TUPLE_ORIG] || !cda[CTA_TUPLE_REPLY])
2424 				return -EINVAL;
2425 			if (otuple.dst.protonum != rtuple.dst.protonum)
2426 				return -EINVAL;
2427 
2428 			ct = ctnetlink_create_conntrack(info->net, &zone, cda,
2429 							&otuple, &rtuple, u3);
2430 			if (IS_ERR(ct))
2431 				return PTR_ERR(ct);
2432 
2433 			err = 0;
2434 			if (test_bit(IPS_EXPECTED_BIT, &ct->status))
2435 				events = 1 << IPCT_RELATED;
2436 			else
2437 				events = 1 << IPCT_NEW;
2438 
2439 			if (cda[CTA_LABELS] &&
2440 			    ctnetlink_attach_labels(ct, cda) == 0)
2441 				events |= (1 << IPCT_LABEL);
2442 
2443 			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
2444 						      (1 << IPCT_ASSURED) |
2445 						      (1 << IPCT_HELPER) |
2446 						      (1 << IPCT_PROTOINFO) |
2447 						      (1 << IPCT_SEQADJ) |
2448 						      (1 << IPCT_MARK) |
2449 						      (1 << IPCT_SYNPROXY) |
2450 						      events,
2451 						      ct, NETLINK_CB(skb).portid,
2452 						      nlmsg_report(info->nlh));
2453 			nf_ct_put(ct);
2454 		}
2455 
2456 		return err;
2457 	}
2458 	/* implicit 'else' */
2459 
2460 	err = -EEXIST;
2461 	ct = nf_ct_tuplehash_to_ctrack(h);
2462 	if (!(info->nlh->nlmsg_flags & NLM_F_EXCL)) {
2463 		err = ctnetlink_change_conntrack(ct, cda);
2464 		if (err == 0) {
2465 			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
2466 						      (1 << IPCT_ASSURED) |
2467 						      (1 << IPCT_HELPER) |
2468 						      (1 << IPCT_LABEL) |
2469 						      (1 << IPCT_PROTOINFO) |
2470 						      (1 << IPCT_SEQADJ) |
2471 						      (1 << IPCT_MARK) |
2472 						      (1 << IPCT_SYNPROXY),
2473 						      ct, NETLINK_CB(skb).portid,
2474 						      nlmsg_report(info->nlh));
2475 		}
2476 	}
2477 
2478 	nf_ct_put(ct);
2479 	return err;
2480 }
2481 
2482 static int
ctnetlink_ct_stat_cpu_fill_info(struct sk_buff * skb,u32 portid,u32 seq,__u16 cpu,const struct ip_conntrack_stat * st)2483 ctnetlink_ct_stat_cpu_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
2484 				__u16 cpu, const struct ip_conntrack_stat *st)
2485 {
2486 	struct nlmsghdr *nlh;
2487 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
2488 
2489 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK,
2490 			      IPCTNL_MSG_CT_GET_STATS_CPU);
2491 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
2492 			   NFNETLINK_V0, htons(cpu));
2493 	if (!nlh)
2494 		goto nlmsg_failure;
2495 
2496 	if (nla_put_be32(skb, CTA_STATS_FOUND, htonl(st->found)) ||
2497 	    nla_put_be32(skb, CTA_STATS_INVALID, htonl(st->invalid)) ||
2498 	    nla_put_be32(skb, CTA_STATS_INSERT, htonl(st->insert)) ||
2499 	    nla_put_be32(skb, CTA_STATS_INSERT_FAILED,
2500 				htonl(st->insert_failed)) ||
2501 	    nla_put_be32(skb, CTA_STATS_DROP, htonl(st->drop)) ||
2502 	    nla_put_be32(skb, CTA_STATS_EARLY_DROP, htonl(st->early_drop)) ||
2503 	    nla_put_be32(skb, CTA_STATS_ERROR, htonl(st->error)) ||
2504 	    nla_put_be32(skb, CTA_STATS_SEARCH_RESTART,
2505 				htonl(st->search_restart)) ||
2506 	    nla_put_be32(skb, CTA_STATS_CLASH_RESOLVE,
2507 				htonl(st->clash_resolve)) ||
2508 	    nla_put_be32(skb, CTA_STATS_CHAIN_TOOLONG,
2509 			 htonl(st->chaintoolong)))
2510 		goto nla_put_failure;
2511 
2512 	nlmsg_end(skb, nlh);
2513 	return skb->len;
2514 
2515 nla_put_failure:
2516 nlmsg_failure:
2517 	nlmsg_cancel(skb, nlh);
2518 	return -1;
2519 }
2520 
2521 static int
ctnetlink_ct_stat_cpu_dump(struct sk_buff * skb,struct netlink_callback * cb)2522 ctnetlink_ct_stat_cpu_dump(struct sk_buff *skb, struct netlink_callback *cb)
2523 {
2524 	int cpu;
2525 	struct net *net = sock_net(skb->sk);
2526 
2527 	if (cb->args[0] == nr_cpu_ids)
2528 		return 0;
2529 
2530 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
2531 		const struct ip_conntrack_stat *st;
2532 
2533 		if (!cpu_possible(cpu))
2534 			continue;
2535 
2536 		st = per_cpu_ptr(net->ct.stat, cpu);
2537 		if (ctnetlink_ct_stat_cpu_fill_info(skb,
2538 						    NETLINK_CB(cb->skb).portid,
2539 						    cb->nlh->nlmsg_seq,
2540 						    cpu, st) < 0)
2541 				break;
2542 	}
2543 	cb->args[0] = cpu;
2544 
2545 	return skb->len;
2546 }
2547 
ctnetlink_stat_ct_cpu(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2548 static int ctnetlink_stat_ct_cpu(struct sk_buff *skb,
2549 				 const struct nfnl_info *info,
2550 				 const struct nlattr * const cda[])
2551 {
2552 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
2553 		struct netlink_dump_control c = {
2554 			.dump = ctnetlink_ct_stat_cpu_dump,
2555 		};
2556 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
2557 	}
2558 
2559 	return 0;
2560 }
2561 
2562 static int
ctnetlink_stat_ct_fill_info(struct sk_buff * skb,u32 portid,u32 seq,u32 type,struct net * net)2563 ctnetlink_stat_ct_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
2564 			    struct net *net)
2565 {
2566 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
2567 	unsigned int nr_conntracks;
2568 	struct nlmsghdr *nlh;
2569 
2570 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_GET_STATS);
2571 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
2572 			   NFNETLINK_V0, 0);
2573 	if (!nlh)
2574 		goto nlmsg_failure;
2575 
2576 	nr_conntracks = nf_conntrack_count(net);
2577 	if (nla_put_be32(skb, CTA_STATS_GLOBAL_ENTRIES, htonl(nr_conntracks)))
2578 		goto nla_put_failure;
2579 
2580 	if (nla_put_be32(skb, CTA_STATS_GLOBAL_MAX_ENTRIES, htonl(nf_conntrack_max)))
2581 		goto nla_put_failure;
2582 
2583 	nlmsg_end(skb, nlh);
2584 	return skb->len;
2585 
2586 nla_put_failure:
2587 nlmsg_failure:
2588 	nlmsg_cancel(skb, nlh);
2589 	return -1;
2590 }
2591 
ctnetlink_stat_ct(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])2592 static int ctnetlink_stat_ct(struct sk_buff *skb, const struct nfnl_info *info,
2593 			     const struct nlattr * const cda[])
2594 {
2595 	struct sk_buff *skb2;
2596 	int err;
2597 
2598 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
2599 	if (skb2 == NULL)
2600 		return -ENOMEM;
2601 
2602 	err = ctnetlink_stat_ct_fill_info(skb2, NETLINK_CB(skb).portid,
2603 					  info->nlh->nlmsg_seq,
2604 					  NFNL_MSG_TYPE(info->nlh->nlmsg_type),
2605 					  sock_net(skb->sk));
2606 	if (err <= 0) {
2607 		kfree_skb(skb2);
2608 		return -ENOMEM;
2609 	}
2610 
2611 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
2612 }
2613 
2614 static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
2615 	[CTA_EXPECT_MASTER]	= { .type = NLA_NESTED },
2616 	[CTA_EXPECT_TUPLE]	= { .type = NLA_NESTED },
2617 	[CTA_EXPECT_MASK]	= { .type = NLA_NESTED },
2618 	[CTA_EXPECT_TIMEOUT]	= { .type = NLA_U32 },
2619 	[CTA_EXPECT_ID]		= { .type = NLA_U32 },
2620 	[CTA_EXPECT_HELP_NAME]	= { .type = NLA_NUL_STRING,
2621 				    .len = NF_CT_HELPER_NAME_LEN - 1 },
2622 	[CTA_EXPECT_ZONE]	= { .type = NLA_U16 },
2623 	[CTA_EXPECT_FLAGS]	= { .type = NLA_U32 },
2624 	[CTA_EXPECT_CLASS]	= { .type = NLA_U32 },
2625 	[CTA_EXPECT_NAT]	= { .type = NLA_NESTED },
2626 	[CTA_EXPECT_FN]		= { .type = NLA_NUL_STRING },
2627 };
2628 
2629 static struct nf_conntrack_expect *
2630 ctnetlink_alloc_expect(const struct nlattr *const cda[], struct nf_conn *ct,
2631 		       struct nf_conntrack_helper *helper,
2632 		       struct nf_conntrack_tuple *tuple,
2633 		       struct nf_conntrack_tuple *mask);
2634 
2635 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
2636 static size_t
ctnetlink_glue_build_size(const struct nf_conn * ct)2637 ctnetlink_glue_build_size(const struct nf_conn *ct)
2638 {
2639 	return 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
2640 	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
2641 	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
2642 	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
2643 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
2644 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
2645 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
2646 	       + nla_total_size(0) /* CTA_PROTOINFO */
2647 	       + nla_total_size(0) /* CTA_HELP */
2648 	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
2649 	       + ctnetlink_secctx_size(ct)
2650 	       + ctnetlink_acct_size(ct)
2651 	       + ctnetlink_timestamp_size(ct)
2652 #if IS_ENABLED(CONFIG_NF_NAT)
2653 	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
2654 	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
2655 #endif
2656 #ifdef CONFIG_NF_CONNTRACK_MARK
2657 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
2658 #endif
2659 #ifdef CONFIG_NF_CONNTRACK_ZONES
2660 	       + nla_total_size(sizeof(u_int16_t)) /* CTA_ZONE|CTA_TUPLE_ZONE */
2661 #endif
2662 	       + ctnetlink_proto_size(ct)
2663 	       ;
2664 }
2665 
__ctnetlink_glue_build(struct sk_buff * skb,struct nf_conn * ct)2666 static int __ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct)
2667 {
2668 	const struct nf_conntrack_zone *zone;
2669 	struct nlattr *nest_parms;
2670 
2671 	zone = nf_ct_zone(ct);
2672 
2673 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG);
2674 	if (!nest_parms)
2675 		goto nla_put_failure;
2676 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
2677 		goto nla_put_failure;
2678 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
2679 				   NF_CT_ZONE_DIR_ORIG) < 0)
2680 		goto nla_put_failure;
2681 	nla_nest_end(skb, nest_parms);
2682 
2683 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY);
2684 	if (!nest_parms)
2685 		goto nla_put_failure;
2686 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
2687 		goto nla_put_failure;
2688 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
2689 				   NF_CT_ZONE_DIR_REPL) < 0)
2690 		goto nla_put_failure;
2691 	nla_nest_end(skb, nest_parms);
2692 
2693 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
2694 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
2695 		goto nla_put_failure;
2696 
2697 	if (ctnetlink_dump_id(skb, ct) < 0)
2698 		goto nla_put_failure;
2699 
2700 	if (ctnetlink_dump_status(skb, ct) < 0)
2701 		goto nla_put_failure;
2702 
2703 	if (ctnetlink_dump_timeout(skb, ct, false) < 0)
2704 		goto nla_put_failure;
2705 
2706 	if (ctnetlink_dump_protoinfo(skb, ct, false) < 0)
2707 		goto nla_put_failure;
2708 
2709 	if (ctnetlink_dump_acct(skb, ct, IPCTNL_MSG_CT_GET) < 0 ||
2710 	    ctnetlink_dump_timestamp(skb, ct) < 0)
2711 		goto nla_put_failure;
2712 
2713 	if (ctnetlink_dump_helpinfo(skb, ct) < 0)
2714 		goto nla_put_failure;
2715 
2716 #ifdef CONFIG_NF_CONNTRACK_SECMARK
2717 	if (ct->secmark && ctnetlink_dump_secctx(skb, ct) < 0)
2718 		goto nla_put_failure;
2719 #endif
2720 	if (ct->master && ctnetlink_dump_master(skb, ct) < 0)
2721 		goto nla_put_failure;
2722 
2723 	if ((ct->status & IPS_SEQ_ADJUST) &&
2724 	    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
2725 		goto nla_put_failure;
2726 
2727 	if (ctnetlink_dump_ct_synproxy(skb, ct) < 0)
2728 		goto nla_put_failure;
2729 
2730 #ifdef CONFIG_NF_CONNTRACK_MARK
2731 	if (ctnetlink_dump_mark(skb, ct, true) < 0)
2732 		goto nla_put_failure;
2733 #endif
2734 	if (ctnetlink_dump_labels(skb, ct) < 0)
2735 		goto nla_put_failure;
2736 	return 0;
2737 
2738 nla_put_failure:
2739 	return -ENOSPC;
2740 }
2741 
2742 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)2743 ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct,
2744 		     enum ip_conntrack_info ctinfo,
2745 		     u_int16_t ct_attr, u_int16_t ct_info_attr)
2746 {
2747 	struct nlattr *nest_parms;
2748 
2749 	nest_parms = nla_nest_start(skb, ct_attr);
2750 	if (!nest_parms)
2751 		goto nla_put_failure;
2752 
2753 	if (__ctnetlink_glue_build(skb, ct) < 0)
2754 		goto nla_put_failure;
2755 
2756 	nla_nest_end(skb, nest_parms);
2757 
2758 	if (nla_put_be32(skb, ct_info_attr, htonl(ctinfo)))
2759 		goto nla_put_failure;
2760 
2761 	return 0;
2762 
2763 nla_put_failure:
2764 	return -ENOSPC;
2765 }
2766 
2767 static int
ctnetlink_update_status(struct nf_conn * ct,const struct nlattr * const cda[])2768 ctnetlink_update_status(struct nf_conn *ct, const struct nlattr * const cda[])
2769 {
2770 	unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
2771 	unsigned long d = ct->status ^ status;
2772 
2773 	if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
2774 		/* SEEN_REPLY bit can only be set */
2775 		return -EBUSY;
2776 
2777 	if (d & IPS_ASSURED && !(status & IPS_ASSURED))
2778 		/* ASSURED bit can only be set */
2779 		return -EBUSY;
2780 
2781 	/* This check is less strict than ctnetlink_change_status()
2782 	 * because callers often flip IPS_EXPECTED bits when sending
2783 	 * an NFQA_CT attribute to the kernel.  So ignore the
2784 	 * unchangeable bits but do not error out. Also user programs
2785 	 * are allowed to clear the bits that they are allowed to change.
2786 	 */
2787 	__nf_ct_change_status(ct, status, ~status);
2788 	return 0;
2789 }
2790 
2791 static int
ctnetlink_glue_parse_ct(const struct nlattr * cda[],struct nf_conn * ct)2792 ctnetlink_glue_parse_ct(const struct nlattr *cda[], struct nf_conn *ct)
2793 {
2794 	int err;
2795 
2796 	if (cda[CTA_TIMEOUT]) {
2797 		err = ctnetlink_change_timeout(ct, cda);
2798 		if (err < 0)
2799 			return err;
2800 	}
2801 	if (cda[CTA_STATUS]) {
2802 		err = ctnetlink_update_status(ct, cda);
2803 		if (err < 0)
2804 			return err;
2805 	}
2806 	if (cda[CTA_HELP]) {
2807 		err = ctnetlink_change_helper(ct, cda);
2808 		if (err < 0)
2809 			return err;
2810 	}
2811 	if (cda[CTA_LABELS]) {
2812 		err = ctnetlink_attach_labels(ct, cda);
2813 		if (err < 0)
2814 			return err;
2815 	}
2816 #if defined(CONFIG_NF_CONNTRACK_MARK)
2817 	if (cda[CTA_MARK]) {
2818 		ctnetlink_change_mark(ct, cda);
2819 	}
2820 #endif
2821 	return 0;
2822 }
2823 
2824 static int
ctnetlink_glue_parse(const struct nlattr * attr,struct nf_conn * ct)2825 ctnetlink_glue_parse(const struct nlattr *attr, struct nf_conn *ct)
2826 {
2827 	struct nlattr *cda[CTA_MAX+1];
2828 	int ret;
2829 
2830 	ret = nla_parse_nested_deprecated(cda, CTA_MAX, attr, ct_nla_policy,
2831 					  NULL);
2832 	if (ret < 0)
2833 		return ret;
2834 
2835 	return ctnetlink_glue_parse_ct((const struct nlattr **)cda, ct);
2836 }
2837 
ctnetlink_glue_exp_parse(const struct nlattr * const * cda,const struct nf_conn * ct,struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple * mask)2838 static int ctnetlink_glue_exp_parse(const struct nlattr * const *cda,
2839 				    const struct nf_conn *ct,
2840 				    struct nf_conntrack_tuple *tuple,
2841 				    struct nf_conntrack_tuple *mask)
2842 {
2843 	int err;
2844 
2845 	err = ctnetlink_parse_tuple(cda, tuple, CTA_EXPECT_TUPLE,
2846 				    nf_ct_l3num(ct), NULL);
2847 	if (err < 0)
2848 		return err;
2849 
2850 	return ctnetlink_parse_tuple(cda, mask, CTA_EXPECT_MASK,
2851 				     nf_ct_l3num(ct), NULL);
2852 }
2853 
2854 static int
ctnetlink_glue_attach_expect(const struct nlattr * attr,struct nf_conn * ct,u32 portid,u32 report)2855 ctnetlink_glue_attach_expect(const struct nlattr *attr, struct nf_conn *ct,
2856 			     u32 portid, u32 report)
2857 {
2858 	struct nlattr *cda[CTA_EXPECT_MAX+1];
2859 	struct nf_conntrack_tuple tuple, mask;
2860 	struct nf_conntrack_helper *helper = NULL;
2861 	struct nf_conntrack_expect *exp;
2862 	int err;
2863 
2864 	err = nla_parse_nested_deprecated(cda, CTA_EXPECT_MAX, attr,
2865 					  exp_nla_policy, NULL);
2866 	if (err < 0)
2867 		return err;
2868 
2869 	err = ctnetlink_glue_exp_parse((const struct nlattr * const *)cda,
2870 				       ct, &tuple, &mask);
2871 	if (err < 0)
2872 		return err;
2873 
2874 	if (cda[CTA_EXPECT_HELP_NAME]) {
2875 		const char *helpname = nla_data(cda[CTA_EXPECT_HELP_NAME]);
2876 
2877 		helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
2878 						    nf_ct_protonum(ct));
2879 		if (helper == NULL)
2880 			return -EOPNOTSUPP;
2881 	}
2882 
2883 	exp = ctnetlink_alloc_expect((const struct nlattr * const *)cda, ct,
2884 				     helper, &tuple, &mask);
2885 	if (IS_ERR(exp))
2886 		return PTR_ERR(exp);
2887 
2888 	err = nf_ct_expect_related_report(exp, portid, report, 0);
2889 	nf_ct_expect_put(exp);
2890 	return err;
2891 }
2892 
ctnetlink_glue_seqadj(struct sk_buff * skb,struct nf_conn * ct,enum ip_conntrack_info ctinfo,int diff)2893 static void ctnetlink_glue_seqadj(struct sk_buff *skb, struct nf_conn *ct,
2894 				  enum ip_conntrack_info ctinfo, int diff)
2895 {
2896 	if (!(ct->status & IPS_NAT_MASK))
2897 		return;
2898 
2899 	nf_ct_tcp_seqadj_set(skb, ct, ctinfo, diff);
2900 }
2901 
2902 static const struct nfnl_ct_hook ctnetlink_glue_hook = {
2903 	.build_size	= ctnetlink_glue_build_size,
2904 	.build		= ctnetlink_glue_build,
2905 	.parse		= ctnetlink_glue_parse,
2906 	.attach_expect	= ctnetlink_glue_attach_expect,
2907 	.seq_adjust	= ctnetlink_glue_seqadj,
2908 };
2909 #endif /* CONFIG_NETFILTER_NETLINK_GLUE_CT */
2910 
2911 /***********************************************************************
2912  * EXPECT
2913  ***********************************************************************/
2914 
ctnetlink_exp_dump_tuple(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,u32 type)2915 static int ctnetlink_exp_dump_tuple(struct sk_buff *skb,
2916 				    const struct nf_conntrack_tuple *tuple,
2917 				    u32 type)
2918 {
2919 	struct nlattr *nest_parms;
2920 
2921 	nest_parms = nla_nest_start(skb, type);
2922 	if (!nest_parms)
2923 		goto nla_put_failure;
2924 	if (ctnetlink_dump_tuples(skb, tuple) < 0)
2925 		goto nla_put_failure;
2926 	nla_nest_end(skb, nest_parms);
2927 
2928 	return 0;
2929 
2930 nla_put_failure:
2931 	return -1;
2932 }
2933 
ctnetlink_exp_dump_mask(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_tuple_mask * mask)2934 static int ctnetlink_exp_dump_mask(struct sk_buff *skb,
2935 				   const struct nf_conntrack_tuple *tuple,
2936 				   const struct nf_conntrack_tuple_mask *mask)
2937 {
2938 	const struct nf_conntrack_l4proto *l4proto;
2939 	struct nf_conntrack_tuple m;
2940 	struct nlattr *nest_parms;
2941 	int ret;
2942 
2943 	memset(&m, 0xFF, sizeof(m));
2944 	memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
2945 	m.src.u.all = mask->src.u.all;
2946 	m.src.l3num = tuple->src.l3num;
2947 	m.dst.protonum = tuple->dst.protonum;
2948 
2949 	nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK);
2950 	if (!nest_parms)
2951 		goto nla_put_failure;
2952 
2953 	rcu_read_lock();
2954 	ret = ctnetlink_dump_tuples_ip(skb, &m);
2955 	if (ret >= 0) {
2956 		l4proto = nf_ct_l4proto_find(tuple->dst.protonum);
2957 		ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
2958 	}
2959 	rcu_read_unlock();
2960 
2961 	if (unlikely(ret < 0))
2962 		goto nla_put_failure;
2963 
2964 	nla_nest_end(skb, nest_parms);
2965 
2966 	return 0;
2967 
2968 nla_put_failure:
2969 	return -1;
2970 }
2971 
2972 #if IS_ENABLED(CONFIG_NF_NAT)
2973 static const union nf_inet_addr any_addr;
2974 #endif
2975 
nf_expect_get_id(const struct nf_conntrack_expect * exp)2976 static __be32 nf_expect_get_id(const struct nf_conntrack_expect *exp)
2977 {
2978 	static siphash_aligned_key_t exp_id_seed;
2979 	unsigned long a, b, c, d;
2980 
2981 	net_get_random_once(&exp_id_seed, sizeof(exp_id_seed));
2982 
2983 	a = (unsigned long)exp;
2984 	b = (unsigned long)exp->helper;
2985 	c = (unsigned long)exp->master;
2986 	d = (unsigned long)siphash(&exp->tuple, sizeof(exp->tuple), &exp_id_seed);
2987 
2988 #ifdef CONFIG_64BIT
2989 	return (__force __be32)siphash_4u64((u64)a, (u64)b, (u64)c, (u64)d, &exp_id_seed);
2990 #else
2991 	return (__force __be32)siphash_4u32((u32)a, (u32)b, (u32)c, (u32)d, &exp_id_seed);
2992 #endif
2993 }
2994 
2995 static int
ctnetlink_exp_dump_expect(struct sk_buff * skb,const struct nf_conntrack_expect * exp)2996 ctnetlink_exp_dump_expect(struct sk_buff *skb,
2997 			  const struct nf_conntrack_expect *exp)
2998 {
2999 	struct nf_conn *master = exp->master;
3000 	long timeout = ((long)exp->timeout.expires - (long)jiffies) / HZ;
3001 	struct nf_conn_help *help;
3002 #if IS_ENABLED(CONFIG_NF_NAT)
3003 	struct nlattr *nest_parms;
3004 	struct nf_conntrack_tuple nat_tuple = {};
3005 #endif
3006 	struct nf_ct_helper_expectfn *expfn;
3007 
3008 	if (timeout < 0)
3009 		timeout = 0;
3010 
3011 	if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
3012 		goto nla_put_failure;
3013 	if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
3014 		goto nla_put_failure;
3015 	if (ctnetlink_exp_dump_tuple(skb,
3016 				 &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
3017 				 CTA_EXPECT_MASTER) < 0)
3018 		goto nla_put_failure;
3019 
3020 #if IS_ENABLED(CONFIG_NF_NAT)
3021 	if (!nf_inet_addr_cmp(&exp->saved_addr, &any_addr) ||
3022 	    exp->saved_proto.all) {
3023 		nest_parms = nla_nest_start(skb, CTA_EXPECT_NAT);
3024 		if (!nest_parms)
3025 			goto nla_put_failure;
3026 
3027 		if (nla_put_be32(skb, CTA_EXPECT_NAT_DIR, htonl(exp->dir)))
3028 			goto nla_put_failure;
3029 
3030 		nat_tuple.src.l3num = nf_ct_l3num(master);
3031 		nat_tuple.src.u3 = exp->saved_addr;
3032 		nat_tuple.dst.protonum = nf_ct_protonum(master);
3033 		nat_tuple.src.u = exp->saved_proto;
3034 
3035 		if (ctnetlink_exp_dump_tuple(skb, &nat_tuple,
3036 						CTA_EXPECT_NAT_TUPLE) < 0)
3037 	                goto nla_put_failure;
3038 	        nla_nest_end(skb, nest_parms);
3039 	}
3040 #endif
3041 	if (nla_put_be32(skb, CTA_EXPECT_TIMEOUT, htonl(timeout)) ||
3042 	    nla_put_be32(skb, CTA_EXPECT_ID, nf_expect_get_id(exp)) ||
3043 	    nla_put_be32(skb, CTA_EXPECT_FLAGS, htonl(exp->flags)) ||
3044 	    nla_put_be32(skb, CTA_EXPECT_CLASS, htonl(exp->class)))
3045 		goto nla_put_failure;
3046 	help = nfct_help(master);
3047 	if (help) {
3048 		struct nf_conntrack_helper *helper;
3049 
3050 		helper = rcu_dereference(help->helper);
3051 		if (helper &&
3052 		    nla_put_string(skb, CTA_EXPECT_HELP_NAME, helper->name))
3053 			goto nla_put_failure;
3054 	}
3055 	expfn = nf_ct_helper_expectfn_find_by_symbol(exp->expectfn);
3056 	if (expfn != NULL &&
3057 	    nla_put_string(skb, CTA_EXPECT_FN, expfn->name))
3058 		goto nla_put_failure;
3059 
3060 	return 0;
3061 
3062 nla_put_failure:
3063 	return -1;
3064 }
3065 
3066 static int
ctnetlink_exp_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int event,const struct nf_conntrack_expect * exp)3067 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
3068 			int event, const struct nf_conntrack_expect *exp)
3069 {
3070 	struct nlmsghdr *nlh;
3071 	unsigned int flags = portid ? NLM_F_MULTI : 0;
3072 
3073 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK_EXP, event);
3074 	nlh = nfnl_msg_put(skb, portid, seq, event, flags,
3075 			   exp->tuple.src.l3num, NFNETLINK_V0, 0);
3076 	if (!nlh)
3077 		goto nlmsg_failure;
3078 
3079 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
3080 		goto nla_put_failure;
3081 
3082 	nlmsg_end(skb, nlh);
3083 	return skb->len;
3084 
3085 nlmsg_failure:
3086 nla_put_failure:
3087 	nlmsg_cancel(skb, nlh);
3088 	return -1;
3089 }
3090 
3091 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3092 static int
ctnetlink_expect_event(unsigned int events,const struct nf_exp_event * item)3093 ctnetlink_expect_event(unsigned int events, const struct nf_exp_event *item)
3094 {
3095 	struct nf_conntrack_expect *exp = item->exp;
3096 	struct net *net = nf_ct_exp_net(exp);
3097 	struct nlmsghdr *nlh;
3098 	struct sk_buff *skb;
3099 	unsigned int type, group;
3100 	int flags = 0;
3101 
3102 	if (events & (1 << IPEXP_DESTROY)) {
3103 		type = IPCTNL_MSG_EXP_DELETE;
3104 		group = NFNLGRP_CONNTRACK_EXP_DESTROY;
3105 	} else if (events & (1 << IPEXP_NEW)) {
3106 		type = IPCTNL_MSG_EXP_NEW;
3107 		flags = NLM_F_CREATE|NLM_F_EXCL;
3108 		group = NFNLGRP_CONNTRACK_EXP_NEW;
3109 	} else
3110 		return 0;
3111 
3112 	if (!item->report && !nfnetlink_has_listeners(net, group))
3113 		return 0;
3114 
3115 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
3116 	if (skb == NULL)
3117 		goto errout;
3118 
3119 	type = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK_EXP, type);
3120 	nlh = nfnl_msg_put(skb, item->portid, 0, type, flags,
3121 			   exp->tuple.src.l3num, NFNETLINK_V0, 0);
3122 	if (!nlh)
3123 		goto nlmsg_failure;
3124 
3125 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
3126 		goto nla_put_failure;
3127 
3128 	nlmsg_end(skb, nlh);
3129 	nfnetlink_send(skb, net, item->portid, group, item->report, GFP_ATOMIC);
3130 	return 0;
3131 
3132 nla_put_failure:
3133 	nlmsg_cancel(skb, nlh);
3134 nlmsg_failure:
3135 	kfree_skb(skb);
3136 errout:
3137 	nfnetlink_set_err(net, 0, 0, -ENOBUFS);
3138 	return 0;
3139 }
3140 #endif
ctnetlink_exp_done(struct netlink_callback * cb)3141 static int ctnetlink_exp_done(struct netlink_callback *cb)
3142 {
3143 	if (cb->args[1])
3144 		nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
3145 	return 0;
3146 }
3147 
3148 static int
ctnetlink_exp_dump_table(struct sk_buff * skb,struct netlink_callback * cb)3149 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
3150 {
3151 	struct net *net = sock_net(skb->sk);
3152 	struct nf_conntrack_expect *exp, *last;
3153 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
3154 	u_int8_t l3proto = nfmsg->nfgen_family;
3155 
3156 	rcu_read_lock();
3157 	last = (struct nf_conntrack_expect *)cb->args[1];
3158 	for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
3159 restart:
3160 		hlist_for_each_entry_rcu(exp, &nf_ct_expect_hash[cb->args[0]],
3161 					 hnode) {
3162 			if (l3proto && exp->tuple.src.l3num != l3proto)
3163 				continue;
3164 
3165 			if (!net_eq(nf_ct_net(exp->master), net))
3166 				continue;
3167 
3168 			if (cb->args[1]) {
3169 				if (exp != last)
3170 					continue;
3171 				cb->args[1] = 0;
3172 			}
3173 			if (ctnetlink_exp_fill_info(skb,
3174 						    NETLINK_CB(cb->skb).portid,
3175 						    cb->nlh->nlmsg_seq,
3176 						    IPCTNL_MSG_EXP_NEW,
3177 						    exp) < 0) {
3178 				if (!refcount_inc_not_zero(&exp->use))
3179 					continue;
3180 				cb->args[1] = (unsigned long)exp;
3181 				goto out;
3182 			}
3183 		}
3184 		if (cb->args[1]) {
3185 			cb->args[1] = 0;
3186 			goto restart;
3187 		}
3188 	}
3189 out:
3190 	rcu_read_unlock();
3191 	if (last)
3192 		nf_ct_expect_put(last);
3193 
3194 	return skb->len;
3195 }
3196 
3197 static int
ctnetlink_exp_ct_dump_table(struct sk_buff * skb,struct netlink_callback * cb)3198 ctnetlink_exp_ct_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
3199 {
3200 	struct nf_conntrack_expect *exp, *last;
3201 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
3202 	struct nf_conn *ct = cb->data;
3203 	struct nf_conn_help *help = nfct_help(ct);
3204 	u_int8_t l3proto = nfmsg->nfgen_family;
3205 
3206 	if (cb->args[0])
3207 		return 0;
3208 
3209 	rcu_read_lock();
3210 	last = (struct nf_conntrack_expect *)cb->args[1];
3211 restart:
3212 	hlist_for_each_entry_rcu(exp, &help->expectations, lnode) {
3213 		if (l3proto && exp->tuple.src.l3num != l3proto)
3214 			continue;
3215 		if (cb->args[1]) {
3216 			if (exp != last)
3217 				continue;
3218 			cb->args[1] = 0;
3219 		}
3220 		if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).portid,
3221 					    cb->nlh->nlmsg_seq,
3222 					    IPCTNL_MSG_EXP_NEW,
3223 					    exp) < 0) {
3224 			if (!refcount_inc_not_zero(&exp->use))
3225 				continue;
3226 			cb->args[1] = (unsigned long)exp;
3227 			goto out;
3228 		}
3229 	}
3230 	if (cb->args[1]) {
3231 		cb->args[1] = 0;
3232 		goto restart;
3233 	}
3234 	cb->args[0] = 1;
3235 out:
3236 	rcu_read_unlock();
3237 	if (last)
3238 		nf_ct_expect_put(last);
3239 
3240 	return skb->len;
3241 }
3242 
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)3243 static int ctnetlink_dump_exp_ct(struct net *net, struct sock *ctnl,
3244 				 struct sk_buff *skb,
3245 				 const struct nlmsghdr *nlh,
3246 				 const struct nlattr * const cda[],
3247 				 struct netlink_ext_ack *extack)
3248 {
3249 	int err;
3250 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3251 	u_int8_t u3 = nfmsg->nfgen_family;
3252 	struct nf_conntrack_tuple tuple;
3253 	struct nf_conntrack_tuple_hash *h;
3254 	struct nf_conn *ct;
3255 	struct nf_conntrack_zone zone;
3256 	struct netlink_dump_control c = {
3257 		.dump = ctnetlink_exp_ct_dump_table,
3258 		.done = ctnetlink_exp_done,
3259 	};
3260 
3261 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER,
3262 				    u3, NULL);
3263 	if (err < 0)
3264 		return err;
3265 
3266 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3267 	if (err < 0)
3268 		return err;
3269 
3270 	h = nf_conntrack_find_get(net, &zone, &tuple);
3271 	if (!h)
3272 		return -ENOENT;
3273 
3274 	ct = nf_ct_tuplehash_to_ctrack(h);
3275 	/* No expectation linked to this connection tracking. */
3276 	if (!nfct_help(ct)) {
3277 		nf_ct_put(ct);
3278 		return 0;
3279 	}
3280 
3281 	c.data = ct;
3282 
3283 	err = netlink_dump_start(ctnl, skb, nlh, &c);
3284 	nf_ct_put(ct);
3285 
3286 	return err;
3287 }
3288 
ctnetlink_get_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3289 static int ctnetlink_get_expect(struct sk_buff *skb,
3290 				const struct nfnl_info *info,
3291 				const struct nlattr * const cda[])
3292 {
3293 	u_int8_t u3 = info->nfmsg->nfgen_family;
3294 	struct nf_conntrack_tuple tuple;
3295 	struct nf_conntrack_expect *exp;
3296 	struct nf_conntrack_zone zone;
3297 	struct sk_buff *skb2;
3298 	int err;
3299 
3300 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
3301 		if (cda[CTA_EXPECT_MASTER])
3302 			return ctnetlink_dump_exp_ct(info->net, info->sk, skb,
3303 						     info->nlh, cda,
3304 						     info->extack);
3305 		else {
3306 			struct netlink_dump_control c = {
3307 				.dump = ctnetlink_exp_dump_table,
3308 				.done = ctnetlink_exp_done,
3309 			};
3310 			return netlink_dump_start(info->sk, skb, info->nlh, &c);
3311 		}
3312 	}
3313 
3314 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3315 	if (err < 0)
3316 		return err;
3317 
3318 	if (cda[CTA_EXPECT_TUPLE])
3319 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3320 					    u3, NULL);
3321 	else if (cda[CTA_EXPECT_MASTER])
3322 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER,
3323 					    u3, NULL);
3324 	else
3325 		return -EINVAL;
3326 
3327 	if (err < 0)
3328 		return err;
3329 
3330 	exp = nf_ct_expect_find_get(info->net, &zone, &tuple);
3331 	if (!exp)
3332 		return -ENOENT;
3333 
3334 	if (cda[CTA_EXPECT_ID]) {
3335 		__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
3336 
3337 		if (id != nf_expect_get_id(exp)) {
3338 			nf_ct_expect_put(exp);
3339 			return -ENOENT;
3340 		}
3341 	}
3342 
3343 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
3344 	if (!skb2) {
3345 		nf_ct_expect_put(exp);
3346 		return -ENOMEM;
3347 	}
3348 
3349 	rcu_read_lock();
3350 	err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).portid,
3351 				      info->nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
3352 				      exp);
3353 	rcu_read_unlock();
3354 	nf_ct_expect_put(exp);
3355 	if (err <= 0) {
3356 		kfree_skb(skb2);
3357 		return -ENOMEM;
3358 	}
3359 
3360 	return nfnetlink_unicast(skb2, info->net, NETLINK_CB(skb).portid);
3361 }
3362 
expect_iter_name(struct nf_conntrack_expect * exp,void * data)3363 static bool expect_iter_name(struct nf_conntrack_expect *exp, void *data)
3364 {
3365 	struct nf_conntrack_helper *helper;
3366 	const struct nf_conn_help *m_help;
3367 	const char *name = data;
3368 
3369 	m_help = nfct_help(exp->master);
3370 
3371 	helper = rcu_dereference(m_help->helper);
3372 	if (!helper)
3373 		return false;
3374 
3375 	return strcmp(helper->name, name) == 0;
3376 }
3377 
expect_iter_all(struct nf_conntrack_expect * exp,void * data)3378 static bool expect_iter_all(struct nf_conntrack_expect *exp, void *data)
3379 {
3380 	return true;
3381 }
3382 
ctnetlink_del_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3383 static int ctnetlink_del_expect(struct sk_buff *skb,
3384 				const struct nfnl_info *info,
3385 				const struct nlattr * const cda[])
3386 {
3387 	u_int8_t u3 = info->nfmsg->nfgen_family;
3388 	struct nf_conntrack_expect *exp;
3389 	struct nf_conntrack_tuple tuple;
3390 	struct nf_conntrack_zone zone;
3391 	int err;
3392 
3393 	if (cda[CTA_EXPECT_TUPLE]) {
3394 		/* delete a single expect by tuple */
3395 		err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3396 		if (err < 0)
3397 			return err;
3398 
3399 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3400 					    u3, NULL);
3401 		if (err < 0)
3402 			return err;
3403 
3404 		/* bump usage count to 2 */
3405 		exp = nf_ct_expect_find_get(info->net, &zone, &tuple);
3406 		if (!exp)
3407 			return -ENOENT;
3408 
3409 		if (cda[CTA_EXPECT_ID]) {
3410 			__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
3411 
3412 			if (id != nf_expect_get_id(exp)) {
3413 				nf_ct_expect_put(exp);
3414 				return -ENOENT;
3415 			}
3416 		}
3417 
3418 		/* after list removal, usage count == 1 */
3419 		spin_lock_bh(&nf_conntrack_expect_lock);
3420 		if (del_timer(&exp->timeout)) {
3421 			nf_ct_unlink_expect_report(exp, NETLINK_CB(skb).portid,
3422 						   nlmsg_report(info->nlh));
3423 			nf_ct_expect_put(exp);
3424 		}
3425 		spin_unlock_bh(&nf_conntrack_expect_lock);
3426 		/* have to put what we 'get' above.
3427 		 * after this line usage count == 0 */
3428 		nf_ct_expect_put(exp);
3429 	} else if (cda[CTA_EXPECT_HELP_NAME]) {
3430 		char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
3431 
3432 		nf_ct_expect_iterate_net(info->net, expect_iter_name, name,
3433 					 NETLINK_CB(skb).portid,
3434 					 nlmsg_report(info->nlh));
3435 	} else {
3436 		/* This basically means we have to flush everything*/
3437 		nf_ct_expect_iterate_net(info->net, expect_iter_all, NULL,
3438 					 NETLINK_CB(skb).portid,
3439 					 nlmsg_report(info->nlh));
3440 	}
3441 
3442 	return 0;
3443 }
3444 static int
ctnetlink_change_expect(struct nf_conntrack_expect * x,const struct nlattr * const cda[])3445 ctnetlink_change_expect(struct nf_conntrack_expect *x,
3446 			const struct nlattr * const cda[])
3447 {
3448 	if (cda[CTA_EXPECT_TIMEOUT]) {
3449 		if (!del_timer(&x->timeout))
3450 			return -ETIME;
3451 
3452 		x->timeout.expires = jiffies +
3453 			ntohl(nla_get_be32(cda[CTA_EXPECT_TIMEOUT])) * HZ;
3454 		add_timer(&x->timeout);
3455 	}
3456 	return 0;
3457 }
3458 
3459 #if IS_ENABLED(CONFIG_NF_NAT)
3460 static const struct nla_policy exp_nat_nla_policy[CTA_EXPECT_NAT_MAX+1] = {
3461 	[CTA_EXPECT_NAT_DIR]	= { .type = NLA_U32 },
3462 	[CTA_EXPECT_NAT_TUPLE]	= { .type = NLA_NESTED },
3463 };
3464 #endif
3465 
3466 static int
ctnetlink_parse_expect_nat(const struct nlattr * attr,struct nf_conntrack_expect * exp,u_int8_t u3)3467 ctnetlink_parse_expect_nat(const struct nlattr *attr,
3468 			   struct nf_conntrack_expect *exp,
3469 			   u_int8_t u3)
3470 {
3471 #if IS_ENABLED(CONFIG_NF_NAT)
3472 	struct nlattr *tb[CTA_EXPECT_NAT_MAX+1];
3473 	struct nf_conntrack_tuple nat_tuple = {};
3474 	int err;
3475 
3476 	err = nla_parse_nested_deprecated(tb, CTA_EXPECT_NAT_MAX, attr,
3477 					  exp_nat_nla_policy, NULL);
3478 	if (err < 0)
3479 		return err;
3480 
3481 	if (!tb[CTA_EXPECT_NAT_DIR] || !tb[CTA_EXPECT_NAT_TUPLE])
3482 		return -EINVAL;
3483 
3484 	err = ctnetlink_parse_tuple((const struct nlattr * const *)tb,
3485 				    &nat_tuple, CTA_EXPECT_NAT_TUPLE,
3486 				    u3, NULL);
3487 	if (err < 0)
3488 		return err;
3489 
3490 	exp->saved_addr = nat_tuple.src.u3;
3491 	exp->saved_proto = nat_tuple.src.u;
3492 	exp->dir = ntohl(nla_get_be32(tb[CTA_EXPECT_NAT_DIR]));
3493 
3494 	return 0;
3495 #else
3496 	return -EOPNOTSUPP;
3497 #endif
3498 }
3499 
3500 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)3501 ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,
3502 		       struct nf_conntrack_helper *helper,
3503 		       struct nf_conntrack_tuple *tuple,
3504 		       struct nf_conntrack_tuple *mask)
3505 {
3506 	u_int32_t class = 0;
3507 	struct nf_conntrack_expect *exp;
3508 	struct nf_conn_help *help;
3509 	int err;
3510 
3511 	help = nfct_help(ct);
3512 	if (!help)
3513 		return ERR_PTR(-EOPNOTSUPP);
3514 
3515 	if (cda[CTA_EXPECT_CLASS] && helper) {
3516 		class = ntohl(nla_get_be32(cda[CTA_EXPECT_CLASS]));
3517 		if (class > helper->expect_class_max)
3518 			return ERR_PTR(-EINVAL);
3519 	}
3520 	exp = nf_ct_expect_alloc(ct);
3521 	if (!exp)
3522 		return ERR_PTR(-ENOMEM);
3523 
3524 	if (cda[CTA_EXPECT_FLAGS]) {
3525 		exp->flags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
3526 		exp->flags &= ~NF_CT_EXPECT_USERSPACE;
3527 	} else {
3528 		exp->flags = 0;
3529 	}
3530 	if (cda[CTA_EXPECT_FN]) {
3531 		const char *name = nla_data(cda[CTA_EXPECT_FN]);
3532 		struct nf_ct_helper_expectfn *expfn;
3533 
3534 		expfn = nf_ct_helper_expectfn_find_by_name(name);
3535 		if (expfn == NULL) {
3536 			err = -EINVAL;
3537 			goto err_out;
3538 		}
3539 		exp->expectfn = expfn->expectfn;
3540 	} else
3541 		exp->expectfn = NULL;
3542 
3543 	exp->class = class;
3544 	exp->master = ct;
3545 	exp->helper = helper;
3546 	exp->tuple = *tuple;
3547 	exp->mask.src.u3 = mask->src.u3;
3548 	exp->mask.src.u.all = mask->src.u.all;
3549 
3550 	if (cda[CTA_EXPECT_NAT]) {
3551 		err = ctnetlink_parse_expect_nat(cda[CTA_EXPECT_NAT],
3552 						 exp, nf_ct_l3num(ct));
3553 		if (err < 0)
3554 			goto err_out;
3555 	}
3556 	return exp;
3557 err_out:
3558 	nf_ct_expect_put(exp);
3559 	return ERR_PTR(err);
3560 }
3561 
3562 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)3563 ctnetlink_create_expect(struct net *net,
3564 			const struct nf_conntrack_zone *zone,
3565 			const struct nlattr * const cda[],
3566 			u_int8_t u3, u32 portid, int report)
3567 {
3568 	struct nf_conntrack_tuple tuple, mask, master_tuple;
3569 	struct nf_conntrack_tuple_hash *h = NULL;
3570 	struct nf_conntrack_helper *helper = NULL;
3571 	struct nf_conntrack_expect *exp;
3572 	struct nf_conn *ct;
3573 	int err;
3574 
3575 	/* caller guarantees that those three CTA_EXPECT_* exist */
3576 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3577 				    u3, NULL);
3578 	if (err < 0)
3579 		return err;
3580 	err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK,
3581 				    u3, NULL);
3582 	if (err < 0)
3583 		return err;
3584 	err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER,
3585 				    u3, NULL);
3586 	if (err < 0)
3587 		return err;
3588 
3589 	/* Look for master conntrack of this expectation */
3590 	h = nf_conntrack_find_get(net, zone, &master_tuple);
3591 	if (!h)
3592 		return -ENOENT;
3593 	ct = nf_ct_tuplehash_to_ctrack(h);
3594 
3595 	rcu_read_lock();
3596 	if (cda[CTA_EXPECT_HELP_NAME]) {
3597 		const char *helpname = nla_data(cda[CTA_EXPECT_HELP_NAME]);
3598 
3599 		helper = __nf_conntrack_helper_find(helpname, u3,
3600 						    nf_ct_protonum(ct));
3601 		if (helper == NULL) {
3602 			rcu_read_unlock();
3603 #ifdef CONFIG_MODULES
3604 			if (request_module("nfct-helper-%s", helpname) < 0) {
3605 				err = -EOPNOTSUPP;
3606 				goto err_ct;
3607 			}
3608 			rcu_read_lock();
3609 			helper = __nf_conntrack_helper_find(helpname, u3,
3610 							    nf_ct_protonum(ct));
3611 			if (helper) {
3612 				err = -EAGAIN;
3613 				goto err_rcu;
3614 			}
3615 			rcu_read_unlock();
3616 #endif
3617 			err = -EOPNOTSUPP;
3618 			goto err_ct;
3619 		}
3620 	}
3621 
3622 	exp = ctnetlink_alloc_expect(cda, ct, helper, &tuple, &mask);
3623 	if (IS_ERR(exp)) {
3624 		err = PTR_ERR(exp);
3625 		goto err_rcu;
3626 	}
3627 
3628 	err = nf_ct_expect_related_report(exp, portid, report, 0);
3629 	nf_ct_expect_put(exp);
3630 err_rcu:
3631 	rcu_read_unlock();
3632 err_ct:
3633 	nf_ct_put(ct);
3634 	return err;
3635 }
3636 
ctnetlink_new_expect(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3637 static int ctnetlink_new_expect(struct sk_buff *skb,
3638 				const struct nfnl_info *info,
3639 				const struct nlattr * const cda[])
3640 {
3641 	u_int8_t u3 = info->nfmsg->nfgen_family;
3642 	struct nf_conntrack_tuple tuple;
3643 	struct nf_conntrack_expect *exp;
3644 	struct nf_conntrack_zone zone;
3645 	int err;
3646 
3647 	if (!cda[CTA_EXPECT_TUPLE]
3648 	    || !cda[CTA_EXPECT_MASK]
3649 	    || !cda[CTA_EXPECT_MASTER])
3650 		return -EINVAL;
3651 
3652 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3653 	if (err < 0)
3654 		return err;
3655 
3656 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3657 				    u3, NULL);
3658 	if (err < 0)
3659 		return err;
3660 
3661 	spin_lock_bh(&nf_conntrack_expect_lock);
3662 	exp = __nf_ct_expect_find(info->net, &zone, &tuple);
3663 	if (!exp) {
3664 		spin_unlock_bh(&nf_conntrack_expect_lock);
3665 		err = -ENOENT;
3666 		if (info->nlh->nlmsg_flags & NLM_F_CREATE) {
3667 			err = ctnetlink_create_expect(info->net, &zone, cda, u3,
3668 						      NETLINK_CB(skb).portid,
3669 						      nlmsg_report(info->nlh));
3670 		}
3671 		return err;
3672 	}
3673 
3674 	err = -EEXIST;
3675 	if (!(info->nlh->nlmsg_flags & NLM_F_EXCL))
3676 		err = ctnetlink_change_expect(exp, cda);
3677 	spin_unlock_bh(&nf_conntrack_expect_lock);
3678 
3679 	return err;
3680 }
3681 
3682 static int
ctnetlink_exp_stat_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int cpu,const struct ip_conntrack_stat * st)3683 ctnetlink_exp_stat_fill_info(struct sk_buff *skb, u32 portid, u32 seq, int cpu,
3684 			     const struct ip_conntrack_stat *st)
3685 {
3686 	struct nlmsghdr *nlh;
3687 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
3688 
3689 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK,
3690 			      IPCTNL_MSG_EXP_GET_STATS_CPU);
3691 	nlh = nfnl_msg_put(skb, portid, seq, event, flags, AF_UNSPEC,
3692 			   NFNETLINK_V0, htons(cpu));
3693 	if (!nlh)
3694 		goto nlmsg_failure;
3695 
3696 	if (nla_put_be32(skb, CTA_STATS_EXP_NEW, htonl(st->expect_new)) ||
3697 	    nla_put_be32(skb, CTA_STATS_EXP_CREATE, htonl(st->expect_create)) ||
3698 	    nla_put_be32(skb, CTA_STATS_EXP_DELETE, htonl(st->expect_delete)))
3699 		goto nla_put_failure;
3700 
3701 	nlmsg_end(skb, nlh);
3702 	return skb->len;
3703 
3704 nla_put_failure:
3705 nlmsg_failure:
3706 	nlmsg_cancel(skb, nlh);
3707 	return -1;
3708 }
3709 
3710 static int
ctnetlink_exp_stat_cpu_dump(struct sk_buff * skb,struct netlink_callback * cb)3711 ctnetlink_exp_stat_cpu_dump(struct sk_buff *skb, struct netlink_callback *cb)
3712 {
3713 	int cpu;
3714 	struct net *net = sock_net(skb->sk);
3715 
3716 	if (cb->args[0] == nr_cpu_ids)
3717 		return 0;
3718 
3719 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
3720 		const struct ip_conntrack_stat *st;
3721 
3722 		if (!cpu_possible(cpu))
3723 			continue;
3724 
3725 		st = per_cpu_ptr(net->ct.stat, cpu);
3726 		if (ctnetlink_exp_stat_fill_info(skb, NETLINK_CB(cb->skb).portid,
3727 						 cb->nlh->nlmsg_seq,
3728 						 cpu, st) < 0)
3729 			break;
3730 	}
3731 	cb->args[0] = cpu;
3732 
3733 	return skb->len;
3734 }
3735 
ctnetlink_stat_exp_cpu(struct sk_buff * skb,const struct nfnl_info * info,const struct nlattr * const cda[])3736 static int ctnetlink_stat_exp_cpu(struct sk_buff *skb,
3737 				  const struct nfnl_info *info,
3738 				  const struct nlattr * const cda[])
3739 {
3740 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
3741 		struct netlink_dump_control c = {
3742 			.dump = ctnetlink_exp_stat_cpu_dump,
3743 		};
3744 		return netlink_dump_start(info->sk, skb, info->nlh, &c);
3745 	}
3746 
3747 	return 0;
3748 }
3749 
3750 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3751 static struct nf_ct_event_notifier ctnl_notifier = {
3752 	.ct_event = ctnetlink_conntrack_event,
3753 	.exp_event = ctnetlink_expect_event,
3754 };
3755 #endif
3756 
3757 static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
3758 	[IPCTNL_MSG_CT_NEW]	= {
3759 		.call		= ctnetlink_new_conntrack,
3760 		.type		= NFNL_CB_MUTEX,
3761 		.attr_count	= CTA_MAX,
3762 		.policy		= ct_nla_policy
3763 	},
3764 	[IPCTNL_MSG_CT_GET]	= {
3765 		.call		= ctnetlink_get_conntrack,
3766 		.type		= NFNL_CB_MUTEX,
3767 		.attr_count	= CTA_MAX,
3768 		.policy		= ct_nla_policy
3769 	},
3770 	[IPCTNL_MSG_CT_DELETE]	= {
3771 		.call		= ctnetlink_del_conntrack,
3772 		.type		= NFNL_CB_MUTEX,
3773 		.attr_count	= CTA_MAX,
3774 		.policy		= ct_nla_policy
3775 	},
3776 	[IPCTNL_MSG_CT_GET_CTRZERO] = {
3777 		.call		= ctnetlink_get_conntrack,
3778 		.type		= NFNL_CB_MUTEX,
3779 		.attr_count	= CTA_MAX,
3780 		.policy		= ct_nla_policy
3781 	},
3782 	[IPCTNL_MSG_CT_GET_STATS_CPU] = {
3783 		.call		= ctnetlink_stat_ct_cpu,
3784 		.type		= NFNL_CB_MUTEX,
3785 	},
3786 	[IPCTNL_MSG_CT_GET_STATS] = {
3787 		.call		= ctnetlink_stat_ct,
3788 		.type		= NFNL_CB_MUTEX,
3789 	},
3790 	[IPCTNL_MSG_CT_GET_DYING] = {
3791 		.call		= ctnetlink_get_ct_dying,
3792 		.type		= NFNL_CB_MUTEX,
3793 	},
3794 	[IPCTNL_MSG_CT_GET_UNCONFIRMED]	= {
3795 		.call		= ctnetlink_get_ct_unconfirmed,
3796 		.type		= NFNL_CB_MUTEX,
3797 	},
3798 };
3799 
3800 static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
3801 	[IPCTNL_MSG_EXP_GET] = {
3802 		.call		= ctnetlink_get_expect,
3803 		.type		= NFNL_CB_MUTEX,
3804 		.attr_count	= CTA_EXPECT_MAX,
3805 		.policy		= exp_nla_policy
3806 	},
3807 	[IPCTNL_MSG_EXP_NEW] = {
3808 		.call		= ctnetlink_new_expect,
3809 		.type		= NFNL_CB_MUTEX,
3810 		.attr_count	= CTA_EXPECT_MAX,
3811 		.policy		= exp_nla_policy
3812 	},
3813 	[IPCTNL_MSG_EXP_DELETE] = {
3814 		.call		= ctnetlink_del_expect,
3815 		.type		= NFNL_CB_MUTEX,
3816 		.attr_count	= CTA_EXPECT_MAX,
3817 		.policy		= exp_nla_policy
3818 	},
3819 	[IPCTNL_MSG_EXP_GET_STATS_CPU] = {
3820 		.call		= ctnetlink_stat_exp_cpu,
3821 		.type		= NFNL_CB_MUTEX,
3822 	},
3823 };
3824 
3825 static const struct nfnetlink_subsystem ctnl_subsys = {
3826 	.name				= "conntrack",
3827 	.subsys_id			= NFNL_SUBSYS_CTNETLINK,
3828 	.cb_count			= IPCTNL_MSG_MAX,
3829 	.cb				= ctnl_cb,
3830 };
3831 
3832 static const struct nfnetlink_subsystem ctnl_exp_subsys = {
3833 	.name				= "conntrack_expect",
3834 	.subsys_id			= NFNL_SUBSYS_CTNETLINK_EXP,
3835 	.cb_count			= IPCTNL_MSG_EXP_MAX,
3836 	.cb				= ctnl_exp_cb,
3837 };
3838 
3839 MODULE_ALIAS("ip_conntrack_netlink");
3840 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
3841 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
3842 
ctnetlink_net_init(struct net * net)3843 static int __net_init ctnetlink_net_init(struct net *net)
3844 {
3845 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3846 	nf_conntrack_register_notifier(net, &ctnl_notifier);
3847 #endif
3848 	return 0;
3849 }
3850 
ctnetlink_net_pre_exit(struct net * net)3851 static void ctnetlink_net_pre_exit(struct net *net)
3852 {
3853 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3854 	nf_conntrack_unregister_notifier(net);
3855 #endif
3856 }
3857 
3858 static struct pernet_operations ctnetlink_net_ops = {
3859 	.init		= ctnetlink_net_init,
3860 	.pre_exit	= ctnetlink_net_pre_exit,
3861 };
3862 
ctnetlink_init(void)3863 static int __init ctnetlink_init(void)
3864 {
3865 	int ret;
3866 
3867 	NL_ASSERT_DUMP_CTX_FITS(struct ctnetlink_list_dump_ctx);
3868 
3869 	ret = nfnetlink_subsys_register(&ctnl_subsys);
3870 	if (ret < 0) {
3871 		pr_err("ctnetlink_init: cannot register with nfnetlink.\n");
3872 		goto err_out;
3873 	}
3874 
3875 	ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
3876 	if (ret < 0) {
3877 		pr_err("ctnetlink_init: cannot register exp with nfnetlink.\n");
3878 		goto err_unreg_subsys;
3879 	}
3880 
3881 	ret = register_pernet_subsys(&ctnetlink_net_ops);
3882 	if (ret < 0) {
3883 		pr_err("ctnetlink_init: cannot register pernet operations\n");
3884 		goto err_unreg_exp_subsys;
3885 	}
3886 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
3887 	/* setup interaction between nf_queue and nf_conntrack_netlink. */
3888 	RCU_INIT_POINTER(nfnl_ct_hook, &ctnetlink_glue_hook);
3889 #endif
3890 	return 0;
3891 
3892 err_unreg_exp_subsys:
3893 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
3894 err_unreg_subsys:
3895 	nfnetlink_subsys_unregister(&ctnl_subsys);
3896 err_out:
3897 	return ret;
3898 }
3899 
ctnetlink_exit(void)3900 static void __exit ctnetlink_exit(void)
3901 {
3902 	unregister_pernet_subsys(&ctnetlink_net_ops);
3903 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
3904 	nfnetlink_subsys_unregister(&ctnl_subsys);
3905 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
3906 	RCU_INIT_POINTER(nfnl_ct_hook, NULL);
3907 #endif
3908 	synchronize_rcu();
3909 }
3910 
3911 module_init(ctnetlink_init);
3912 module_exit(ctnetlink_exit);
3913