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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_l3proto.h>
43 #include <net/netfilter/nf_conntrack_l4proto.h>
44 #include <net/netfilter/nf_conntrack_tuple.h>
45 #include <net/netfilter/nf_conntrack_acct.h>
46 #include <net/netfilter/nf_conntrack_zones.h>
47 #include <net/netfilter/nf_conntrack_timestamp.h>
48 #include <net/netfilter/nf_conntrack_labels.h>
49 #include <net/netfilter/nf_conntrack_seqadj.h>
50 #include <net/netfilter/nf_conntrack_synproxy.h>
51 #ifdef CONFIG_NF_NAT_NEEDED
52 #include <net/netfilter/nf_nat_core.h>
53 #include <net/netfilter/nf_nat_l4proto.h>
54 #include <net/netfilter/nf_nat_helper.h>
55 #endif
56 
57 #include <linux/netfilter/nfnetlink.h>
58 #include <linux/netfilter/nfnetlink_conntrack.h>
59 
60 MODULE_LICENSE("GPL");
61 
62 static char __initdata version[] = "0.93";
63 
ctnetlink_dump_tuples_proto(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_l4proto * l4proto)64 static int ctnetlink_dump_tuples_proto(struct sk_buff *skb,
65 				const struct nf_conntrack_tuple *tuple,
66 				const struct nf_conntrack_l4proto *l4proto)
67 {
68 	int ret = 0;
69 	struct nlattr *nest_parms;
70 
71 	nest_parms = nla_nest_start(skb, CTA_TUPLE_PROTO | NLA_F_NESTED);
72 	if (!nest_parms)
73 		goto nla_put_failure;
74 	if (nla_put_u8(skb, CTA_PROTO_NUM, tuple->dst.protonum))
75 		goto nla_put_failure;
76 
77 	if (likely(l4proto->tuple_to_nlattr))
78 		ret = l4proto->tuple_to_nlattr(skb, tuple);
79 
80 	nla_nest_end(skb, nest_parms);
81 
82 	return ret;
83 
84 nla_put_failure:
85 	return -1;
86 }
87 
ctnetlink_dump_tuples_ip(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_l3proto * l3proto)88 static int ctnetlink_dump_tuples_ip(struct sk_buff *skb,
89 				    const struct nf_conntrack_tuple *tuple,
90 				    const struct nf_conntrack_l3proto *l3proto)
91 {
92 	int ret = 0;
93 	struct nlattr *nest_parms;
94 
95 	nest_parms = nla_nest_start(skb, CTA_TUPLE_IP | NLA_F_NESTED);
96 	if (!nest_parms)
97 		goto nla_put_failure;
98 
99 	if (likely(l3proto->tuple_to_nlattr))
100 		ret = l3proto->tuple_to_nlattr(skb, tuple);
101 
102 	nla_nest_end(skb, nest_parms);
103 
104 	return ret;
105 
106 nla_put_failure:
107 	return -1;
108 }
109 
ctnetlink_dump_tuples(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple)110 static int ctnetlink_dump_tuples(struct sk_buff *skb,
111 				 const struct nf_conntrack_tuple *tuple)
112 {
113 	const struct nf_conntrack_l3proto *l3proto;
114 	const struct nf_conntrack_l4proto *l4proto;
115 	int ret;
116 
117 	rcu_read_lock();
118 	l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
119 	ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
120 
121 	if (ret >= 0) {
122 		l4proto = __nf_ct_l4proto_find(tuple->src.l3num,
123 					       tuple->dst.protonum);
124 		ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
125 	}
126 	rcu_read_unlock();
127 	return ret;
128 }
129 
ctnetlink_dump_zone_id(struct sk_buff * skb,int attrtype,const struct nf_conntrack_zone * zone,int dir)130 static int ctnetlink_dump_zone_id(struct sk_buff *skb, int attrtype,
131 				  const struct nf_conntrack_zone *zone, int dir)
132 {
133 	if (zone->id == NF_CT_DEFAULT_ZONE_ID || zone->dir != dir)
134 		return 0;
135 	if (nla_put_be16(skb, attrtype, htons(zone->id)))
136 		goto nla_put_failure;
137 	return 0;
138 
139 nla_put_failure:
140 	return -1;
141 }
142 
ctnetlink_dump_status(struct sk_buff * skb,const struct nf_conn * ct)143 static int ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
144 {
145 	if (nla_put_be32(skb, CTA_STATUS, htonl(ct->status)))
146 		goto nla_put_failure;
147 	return 0;
148 
149 nla_put_failure:
150 	return -1;
151 }
152 
ctnetlink_dump_timeout(struct sk_buff * skb,const struct nf_conn * ct)153 static int ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
154 {
155 	long timeout = nf_ct_expires(ct) / HZ;
156 
157 	if (nla_put_be32(skb, CTA_TIMEOUT, htonl(timeout)))
158 		goto nla_put_failure;
159 	return 0;
160 
161 nla_put_failure:
162 	return -1;
163 }
164 
ctnetlink_dump_protoinfo(struct sk_buff * skb,struct nf_conn * ct)165 static int ctnetlink_dump_protoinfo(struct sk_buff *skb, struct nf_conn *ct)
166 {
167 	const struct nf_conntrack_l4proto *l4proto;
168 	struct nlattr *nest_proto;
169 	int ret;
170 
171 	l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
172 	if (!l4proto->to_nlattr)
173 		return 0;
174 
175 	nest_proto = nla_nest_start(skb, CTA_PROTOINFO | NLA_F_NESTED);
176 	if (!nest_proto)
177 		goto nla_put_failure;
178 
179 	ret = l4proto->to_nlattr(skb, nest_proto, ct);
180 
181 	nla_nest_end(skb, nest_proto);
182 
183 	return ret;
184 
185 nla_put_failure:
186 	return -1;
187 }
188 
ctnetlink_dump_helpinfo(struct sk_buff * skb,const struct nf_conn * ct)189 static int ctnetlink_dump_helpinfo(struct sk_buff *skb,
190 				   const struct nf_conn *ct)
191 {
192 	struct nlattr *nest_helper;
193 	const struct nf_conn_help *help = nfct_help(ct);
194 	struct nf_conntrack_helper *helper;
195 
196 	if (!help)
197 		return 0;
198 
199 	helper = rcu_dereference(help->helper);
200 	if (!helper)
201 		goto out;
202 
203 	nest_helper = nla_nest_start(skb, CTA_HELP | NLA_F_NESTED);
204 	if (!nest_helper)
205 		goto nla_put_failure;
206 	if (nla_put_string(skb, CTA_HELP_NAME, helper->name))
207 		goto nla_put_failure;
208 
209 	if (helper->to_nlattr)
210 		helper->to_nlattr(skb, ct);
211 
212 	nla_nest_end(skb, nest_helper);
213 out:
214 	return 0;
215 
216 nla_put_failure:
217 	return -1;
218 }
219 
220 static int
dump_counters(struct sk_buff * skb,struct nf_conn_acct * acct,enum ip_conntrack_dir dir,int type)221 dump_counters(struct sk_buff *skb, struct nf_conn_acct *acct,
222 	      enum ip_conntrack_dir dir, int type)
223 {
224 	enum ctattr_type attr = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
225 	struct nf_conn_counter *counter = acct->counter;
226 	struct nlattr *nest_count;
227 	u64 pkts, bytes;
228 
229 	if (type == IPCTNL_MSG_CT_GET_CTRZERO) {
230 		pkts = atomic64_xchg(&counter[dir].packets, 0);
231 		bytes = atomic64_xchg(&counter[dir].bytes, 0);
232 	} else {
233 		pkts = atomic64_read(&counter[dir].packets);
234 		bytes = atomic64_read(&counter[dir].bytes);
235 	}
236 
237 	nest_count = nla_nest_start(skb, attr | NLA_F_NESTED);
238 	if (!nest_count)
239 		goto nla_put_failure;
240 
241 	if (nla_put_be64(skb, CTA_COUNTERS_PACKETS, cpu_to_be64(pkts),
242 			 CTA_COUNTERS_PAD) ||
243 	    nla_put_be64(skb, CTA_COUNTERS_BYTES, cpu_to_be64(bytes),
244 			 CTA_COUNTERS_PAD))
245 		goto nla_put_failure;
246 
247 	nla_nest_end(skb, nest_count);
248 
249 	return 0;
250 
251 nla_put_failure:
252 	return -1;
253 }
254 
255 static int
ctnetlink_dump_acct(struct sk_buff * skb,const struct nf_conn * ct,int type)256 ctnetlink_dump_acct(struct sk_buff *skb, const struct nf_conn *ct, int type)
257 {
258 	struct nf_conn_acct *acct = nf_conn_acct_find(ct);
259 
260 	if (!acct)
261 		return 0;
262 
263 	if (dump_counters(skb, acct, IP_CT_DIR_ORIGINAL, type) < 0)
264 		return -1;
265 	if (dump_counters(skb, acct, IP_CT_DIR_REPLY, type) < 0)
266 		return -1;
267 
268 	return 0;
269 }
270 
271 static int
ctnetlink_dump_timestamp(struct sk_buff * skb,const struct nf_conn * ct)272 ctnetlink_dump_timestamp(struct sk_buff *skb, const struct nf_conn *ct)
273 {
274 	struct nlattr *nest_count;
275 	const struct nf_conn_tstamp *tstamp;
276 
277 	tstamp = nf_conn_tstamp_find(ct);
278 	if (!tstamp)
279 		return 0;
280 
281 	nest_count = nla_nest_start(skb, CTA_TIMESTAMP | NLA_F_NESTED);
282 	if (!nest_count)
283 		goto nla_put_failure;
284 
285 	if (nla_put_be64(skb, CTA_TIMESTAMP_START, cpu_to_be64(tstamp->start),
286 			 CTA_TIMESTAMP_PAD) ||
287 	    (tstamp->stop != 0 && nla_put_be64(skb, CTA_TIMESTAMP_STOP,
288 					       cpu_to_be64(tstamp->stop),
289 					       CTA_TIMESTAMP_PAD)))
290 		goto nla_put_failure;
291 	nla_nest_end(skb, nest_count);
292 
293 	return 0;
294 
295 nla_put_failure:
296 	return -1;
297 }
298 
299 #ifdef CONFIG_NF_CONNTRACK_MARK
ctnetlink_dump_mark(struct sk_buff * skb,const struct nf_conn * ct)300 static int ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
301 {
302 	if (nla_put_be32(skb, CTA_MARK, htonl(ct->mark)))
303 		goto nla_put_failure;
304 	return 0;
305 
306 nla_put_failure:
307 	return -1;
308 }
309 #else
310 #define ctnetlink_dump_mark(a, b) (0)
311 #endif
312 
313 #ifdef CONFIG_NF_CONNTRACK_SECMARK
ctnetlink_dump_secctx(struct sk_buff * skb,const struct nf_conn * ct)314 static int ctnetlink_dump_secctx(struct sk_buff *skb, const struct nf_conn *ct)
315 {
316 	struct nlattr *nest_secctx;
317 	int len, ret;
318 	char *secctx;
319 
320 	ret = security_secid_to_secctx(ct->secmark, &secctx, &len);
321 	if (ret)
322 		return 0;
323 
324 	ret = -1;
325 	nest_secctx = nla_nest_start(skb, CTA_SECCTX | NLA_F_NESTED);
326 	if (!nest_secctx)
327 		goto nla_put_failure;
328 
329 	if (nla_put_string(skb, CTA_SECCTX_NAME, secctx))
330 		goto nla_put_failure;
331 	nla_nest_end(skb, nest_secctx);
332 
333 	ret = 0;
334 nla_put_failure:
335 	security_release_secctx(secctx, len);
336 	return ret;
337 }
338 #else
339 #define ctnetlink_dump_secctx(a, b) (0)
340 #endif
341 
342 #ifdef CONFIG_NF_CONNTRACK_LABELS
ctnetlink_label_size(const struct nf_conn * ct)343 static inline int ctnetlink_label_size(const struct nf_conn *ct)
344 {
345 	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
346 
347 	if (!labels)
348 		return 0;
349 	return nla_total_size(sizeof(labels->bits));
350 }
351 
352 static int
ctnetlink_dump_labels(struct sk_buff * skb,const struct nf_conn * ct)353 ctnetlink_dump_labels(struct sk_buff *skb, const struct nf_conn *ct)
354 {
355 	struct nf_conn_labels *labels = nf_ct_labels_find(ct);
356 	unsigned int i;
357 
358 	if (!labels)
359 		return 0;
360 
361 	i = 0;
362 	do {
363 		if (labels->bits[i] != 0)
364 			return nla_put(skb, CTA_LABELS, sizeof(labels->bits),
365 				       labels->bits);
366 		i++;
367 	} while (i < ARRAY_SIZE(labels->bits));
368 
369 	return 0;
370 }
371 #else
372 #define ctnetlink_dump_labels(a, b) (0)
373 #define ctnetlink_label_size(a)	(0)
374 #endif
375 
376 #define master_tuple(ct) &(ct->master->tuplehash[IP_CT_DIR_ORIGINAL].tuple)
377 
ctnetlink_dump_master(struct sk_buff * skb,const struct nf_conn * ct)378 static int ctnetlink_dump_master(struct sk_buff *skb, const struct nf_conn *ct)
379 {
380 	struct nlattr *nest_parms;
381 
382 	if (!(ct->status & IPS_EXPECTED))
383 		return 0;
384 
385 	nest_parms = nla_nest_start(skb, CTA_TUPLE_MASTER | NLA_F_NESTED);
386 	if (!nest_parms)
387 		goto nla_put_failure;
388 	if (ctnetlink_dump_tuples(skb, master_tuple(ct)) < 0)
389 		goto nla_put_failure;
390 	nla_nest_end(skb, nest_parms);
391 
392 	return 0;
393 
394 nla_put_failure:
395 	return -1;
396 }
397 
398 static int
dump_ct_seq_adj(struct sk_buff * skb,const struct nf_ct_seqadj * seq,int type)399 dump_ct_seq_adj(struct sk_buff *skb, const struct nf_ct_seqadj *seq, int type)
400 {
401 	struct nlattr *nest_parms;
402 
403 	nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
404 	if (!nest_parms)
405 		goto nla_put_failure;
406 
407 	if (nla_put_be32(skb, CTA_SEQADJ_CORRECTION_POS,
408 			 htonl(seq->correction_pos)) ||
409 	    nla_put_be32(skb, CTA_SEQADJ_OFFSET_BEFORE,
410 			 htonl(seq->offset_before)) ||
411 	    nla_put_be32(skb, CTA_SEQADJ_OFFSET_AFTER,
412 			 htonl(seq->offset_after)))
413 		goto nla_put_failure;
414 
415 	nla_nest_end(skb, nest_parms);
416 
417 	return 0;
418 
419 nla_put_failure:
420 	return -1;
421 }
422 
ctnetlink_dump_ct_seq_adj(struct sk_buff * skb,struct nf_conn * ct)423 static int ctnetlink_dump_ct_seq_adj(struct sk_buff *skb, struct nf_conn *ct)
424 {
425 	struct nf_conn_seqadj *seqadj = nfct_seqadj(ct);
426 	struct nf_ct_seqadj *seq;
427 
428 	if (!(ct->status & IPS_SEQ_ADJUST) || !seqadj)
429 		return 0;
430 
431 	spin_lock_bh(&ct->lock);
432 	seq = &seqadj->seq[IP_CT_DIR_ORIGINAL];
433 	if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_ORIG) == -1)
434 		goto err;
435 
436 	seq = &seqadj->seq[IP_CT_DIR_REPLY];
437 	if (dump_ct_seq_adj(skb, seq, CTA_SEQ_ADJ_REPLY) == -1)
438 		goto err;
439 
440 	spin_unlock_bh(&ct->lock);
441 	return 0;
442 err:
443 	spin_unlock_bh(&ct->lock);
444 	return -1;
445 }
446 
ctnetlink_dump_id(struct sk_buff * skb,const struct nf_conn * ct)447 static int ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
448 {
449 	__be32 id = (__force __be32)nf_ct_get_id(ct);
450 
451 	if (nla_put_be32(skb, CTA_ID, id))
452 		goto nla_put_failure;
453 	return 0;
454 
455 nla_put_failure:
456 	return -1;
457 }
458 
ctnetlink_dump_use(struct sk_buff * skb,const struct nf_conn * ct)459 static int ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
460 {
461 	if (nla_put_be32(skb, CTA_USE, htonl(atomic_read(&ct->ct_general.use))))
462 		goto nla_put_failure;
463 	return 0;
464 
465 nla_put_failure:
466 	return -1;
467 }
468 
469 static int
ctnetlink_fill_info(struct sk_buff * skb,u32 portid,u32 seq,u32 type,struct nf_conn * ct)470 ctnetlink_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
471 		    struct nf_conn *ct)
472 {
473 	const struct nf_conntrack_zone *zone;
474 	struct nlmsghdr *nlh;
475 	struct nfgenmsg *nfmsg;
476 	struct nlattr *nest_parms;
477 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
478 
479 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_NEW);
480 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags);
481 	if (nlh == NULL)
482 		goto nlmsg_failure;
483 
484 	nfmsg = nlmsg_data(nlh);
485 	nfmsg->nfgen_family = nf_ct_l3num(ct);
486 	nfmsg->version      = NFNETLINK_V0;
487 	nfmsg->res_id	    = 0;
488 
489 	zone = nf_ct_zone(ct);
490 
491 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
492 	if (!nest_parms)
493 		goto nla_put_failure;
494 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
495 		goto nla_put_failure;
496 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
497 				   NF_CT_ZONE_DIR_ORIG) < 0)
498 		goto nla_put_failure;
499 	nla_nest_end(skb, nest_parms);
500 
501 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
502 	if (!nest_parms)
503 		goto nla_put_failure;
504 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
505 		goto nla_put_failure;
506 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
507 				   NF_CT_ZONE_DIR_REPL) < 0)
508 		goto nla_put_failure;
509 	nla_nest_end(skb, nest_parms);
510 
511 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
512 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
513 		goto nla_put_failure;
514 
515 	if (ctnetlink_dump_status(skb, ct) < 0 ||
516 	    ctnetlink_dump_timeout(skb, ct) < 0 ||
517 	    ctnetlink_dump_acct(skb, ct, type) < 0 ||
518 	    ctnetlink_dump_timestamp(skb, ct) < 0 ||
519 	    ctnetlink_dump_protoinfo(skb, ct) < 0 ||
520 	    ctnetlink_dump_helpinfo(skb, ct) < 0 ||
521 	    ctnetlink_dump_mark(skb, ct) < 0 ||
522 	    ctnetlink_dump_secctx(skb, ct) < 0 ||
523 	    ctnetlink_dump_labels(skb, ct) < 0 ||
524 	    ctnetlink_dump_id(skb, ct) < 0 ||
525 	    ctnetlink_dump_use(skb, ct) < 0 ||
526 	    ctnetlink_dump_master(skb, ct) < 0 ||
527 	    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
528 		goto nla_put_failure;
529 
530 	nlmsg_end(skb, nlh);
531 	return skb->len;
532 
533 nlmsg_failure:
534 nla_put_failure:
535 	nlmsg_cancel(skb, nlh);
536 	return -1;
537 }
538 
ctnetlink_proto_size(const struct nf_conn * ct)539 static inline size_t ctnetlink_proto_size(const struct nf_conn *ct)
540 {
541 	const struct nf_conntrack_l3proto *l3proto;
542 	const struct nf_conntrack_l4proto *l4proto;
543 	size_t len;
544 
545 	l3proto = __nf_ct_l3proto_find(nf_ct_l3num(ct));
546 	len = l3proto->nla_size;
547 	len *= 3u; /* ORIG, REPLY, MASTER */
548 
549 	l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
550 	len += l4proto->nla_size;
551 
552 	return len;
553 }
554 
ctnetlink_acct_size(const struct nf_conn * ct)555 static inline size_t ctnetlink_acct_size(const struct nf_conn *ct)
556 {
557 	if (!nf_ct_ext_exist(ct, NF_CT_EXT_ACCT))
558 		return 0;
559 	return 2 * nla_total_size(0) /* CTA_COUNTERS_ORIG|REPL */
560 	       + 2 * nla_total_size_64bit(sizeof(uint64_t)) /* CTA_COUNTERS_PACKETS */
561 	       + 2 * nla_total_size_64bit(sizeof(uint64_t)) /* CTA_COUNTERS_BYTES */
562 	       ;
563 }
564 
ctnetlink_secctx_size(const struct nf_conn * ct)565 static inline int ctnetlink_secctx_size(const struct nf_conn *ct)
566 {
567 #ifdef CONFIG_NF_CONNTRACK_SECMARK
568 	int len, ret;
569 
570 	ret = security_secid_to_secctx(ct->secmark, NULL, &len);
571 	if (ret)
572 		return 0;
573 
574 	return nla_total_size(0) /* CTA_SECCTX */
575 	       + nla_total_size(sizeof(char) * len); /* CTA_SECCTX_NAME */
576 #else
577 	return 0;
578 #endif
579 }
580 
ctnetlink_timestamp_size(const struct nf_conn * ct)581 static inline size_t ctnetlink_timestamp_size(const struct nf_conn *ct)
582 {
583 #ifdef CONFIG_NF_CONNTRACK_TIMESTAMP
584 	if (!nf_ct_ext_exist(ct, NF_CT_EXT_TSTAMP))
585 		return 0;
586 	return nla_total_size(0) + 2 * nla_total_size_64bit(sizeof(uint64_t));
587 #else
588 	return 0;
589 #endif
590 }
591 
592 #ifdef CONFIG_NF_CONNTRACK_EVENTS
ctnetlink_nlmsg_size(const struct nf_conn * ct)593 static size_t ctnetlink_nlmsg_size(const struct nf_conn *ct)
594 {
595 	return NLMSG_ALIGN(sizeof(struct nfgenmsg))
596 	       + 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
597 	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
598 	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
599 	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
600 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
601 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
602 	       + ctnetlink_acct_size(ct)
603 	       + ctnetlink_timestamp_size(ct)
604 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
605 	       + nla_total_size(0) /* CTA_PROTOINFO */
606 	       + nla_total_size(0) /* CTA_HELP */
607 	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
608 	       + ctnetlink_secctx_size(ct)
609 #ifdef CONFIG_NF_NAT_NEEDED
610 	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
611 	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
612 #endif
613 #ifdef CONFIG_NF_CONNTRACK_MARK
614 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
615 #endif
616 #ifdef CONFIG_NF_CONNTRACK_ZONES
617 	       + nla_total_size(sizeof(u_int16_t)) /* CTA_ZONE|CTA_TUPLE_ZONE */
618 #endif
619 	       + ctnetlink_proto_size(ct)
620 	       + ctnetlink_label_size(ct)
621 	       ;
622 }
623 
624 static int
ctnetlink_conntrack_event(unsigned int events,struct nf_ct_event * item)625 ctnetlink_conntrack_event(unsigned int events, struct nf_ct_event *item)
626 {
627 	const struct nf_conntrack_zone *zone;
628 	struct net *net;
629 	struct nlmsghdr *nlh;
630 	struct nfgenmsg *nfmsg;
631 	struct nlattr *nest_parms;
632 	struct nf_conn *ct = item->ct;
633 	struct sk_buff *skb;
634 	unsigned int type;
635 	unsigned int flags = 0, group;
636 	int err;
637 
638 	if (events & (1 << IPCT_DESTROY)) {
639 		type = IPCTNL_MSG_CT_DELETE;
640 		group = NFNLGRP_CONNTRACK_DESTROY;
641 	} else if (events & ((1 << IPCT_NEW) | (1 << IPCT_RELATED))) {
642 		type = IPCTNL_MSG_CT_NEW;
643 		flags = NLM_F_CREATE|NLM_F_EXCL;
644 		group = NFNLGRP_CONNTRACK_NEW;
645 	} else if (events) {
646 		type = IPCTNL_MSG_CT_NEW;
647 		group = NFNLGRP_CONNTRACK_UPDATE;
648 	} else
649 		return 0;
650 
651 	net = nf_ct_net(ct);
652 	if (!item->report && !nfnetlink_has_listeners(net, group))
653 		return 0;
654 
655 	skb = nlmsg_new(ctnetlink_nlmsg_size(ct), GFP_ATOMIC);
656 	if (skb == NULL)
657 		goto errout;
658 
659 	type = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, type);
660 	nlh = nlmsg_put(skb, item->portid, 0, type, sizeof(*nfmsg), flags);
661 	if (nlh == NULL)
662 		goto nlmsg_failure;
663 
664 	nfmsg = nlmsg_data(nlh);
665 	nfmsg->nfgen_family = nf_ct_l3num(ct);
666 	nfmsg->version	= NFNETLINK_V0;
667 	nfmsg->res_id	= 0;
668 
669 	zone = nf_ct_zone(ct);
670 
671 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
672 	if (!nest_parms)
673 		goto nla_put_failure;
674 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
675 		goto nla_put_failure;
676 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
677 				   NF_CT_ZONE_DIR_ORIG) < 0)
678 		goto nla_put_failure;
679 	nla_nest_end(skb, nest_parms);
680 
681 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
682 	if (!nest_parms)
683 		goto nla_put_failure;
684 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
685 		goto nla_put_failure;
686 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
687 				   NF_CT_ZONE_DIR_REPL) < 0)
688 		goto nla_put_failure;
689 	nla_nest_end(skb, nest_parms);
690 
691 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
692 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
693 		goto nla_put_failure;
694 
695 	if (ctnetlink_dump_id(skb, ct) < 0)
696 		goto nla_put_failure;
697 
698 	if (ctnetlink_dump_status(skb, ct) < 0)
699 		goto nla_put_failure;
700 
701 	if (events & (1 << IPCT_DESTROY)) {
702 		if (ctnetlink_dump_acct(skb, ct, type) < 0 ||
703 		    ctnetlink_dump_timestamp(skb, ct) < 0)
704 			goto nla_put_failure;
705 	} else {
706 		if (ctnetlink_dump_timeout(skb, ct) < 0)
707 			goto nla_put_failure;
708 
709 		if (events & (1 << IPCT_PROTOINFO)
710 		    && ctnetlink_dump_protoinfo(skb, ct) < 0)
711 			goto nla_put_failure;
712 
713 		if ((events & (1 << IPCT_HELPER) || nfct_help(ct))
714 		    && ctnetlink_dump_helpinfo(skb, ct) < 0)
715 			goto nla_put_failure;
716 
717 #ifdef CONFIG_NF_CONNTRACK_SECMARK
718 		if ((events & (1 << IPCT_SECMARK) || ct->secmark)
719 		    && ctnetlink_dump_secctx(skb, ct) < 0)
720 			goto nla_put_failure;
721 #endif
722 		if (events & (1 << IPCT_LABEL) &&
723 		     ctnetlink_dump_labels(skb, ct) < 0)
724 			goto nla_put_failure;
725 
726 		if (events & (1 << IPCT_RELATED) &&
727 		    ctnetlink_dump_master(skb, ct) < 0)
728 			goto nla_put_failure;
729 
730 		if (events & (1 << IPCT_SEQADJ) &&
731 		    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
732 			goto nla_put_failure;
733 	}
734 
735 #ifdef CONFIG_NF_CONNTRACK_MARK
736 	if ((events & (1 << IPCT_MARK) || ct->mark)
737 	    && ctnetlink_dump_mark(skb, ct) < 0)
738 		goto nla_put_failure;
739 #endif
740 	nlmsg_end(skb, nlh);
741 	err = nfnetlink_send(skb, net, item->portid, group, item->report,
742 			     GFP_ATOMIC);
743 	if (err == -ENOBUFS || err == -EAGAIN)
744 		return -ENOBUFS;
745 
746 	return 0;
747 
748 nla_put_failure:
749 	nlmsg_cancel(skb, nlh);
750 nlmsg_failure:
751 	kfree_skb(skb);
752 errout:
753 	if (nfnetlink_set_err(net, 0, group, -ENOBUFS) > 0)
754 		return -ENOBUFS;
755 
756 	return 0;
757 }
758 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
759 
ctnetlink_done(struct netlink_callback * cb)760 static int ctnetlink_done(struct netlink_callback *cb)
761 {
762 	if (cb->args[1])
763 		nf_ct_put((struct nf_conn *)cb->args[1]);
764 	kfree(cb->data);
765 	return 0;
766 }
767 
768 struct ctnetlink_filter {
769 	struct {
770 		u_int32_t val;
771 		u_int32_t mask;
772 	} mark;
773 };
774 
775 static struct ctnetlink_filter *
ctnetlink_alloc_filter(const struct nlattr * const cda[])776 ctnetlink_alloc_filter(const struct nlattr * const cda[])
777 {
778 #ifdef CONFIG_NF_CONNTRACK_MARK
779 	struct ctnetlink_filter *filter;
780 
781 	filter = kzalloc(sizeof(*filter), GFP_KERNEL);
782 	if (filter == NULL)
783 		return ERR_PTR(-ENOMEM);
784 
785 	filter->mark.val = ntohl(nla_get_be32(cda[CTA_MARK]));
786 	filter->mark.mask = ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
787 
788 	return filter;
789 #else
790 	return ERR_PTR(-EOPNOTSUPP);
791 #endif
792 }
793 
ctnetlink_start(struct netlink_callback * cb)794 static int ctnetlink_start(struct netlink_callback *cb)
795 {
796 	const struct nlattr * const *cda = cb->data;
797 	struct ctnetlink_filter *filter = NULL;
798 
799 	if (cda[CTA_MARK] && cda[CTA_MARK_MASK]) {
800 		filter = ctnetlink_alloc_filter(cda);
801 		if (IS_ERR(filter))
802 			return PTR_ERR(filter);
803 	}
804 
805 	cb->data = filter;
806 	return 0;
807 }
808 
ctnetlink_filter_match(struct nf_conn * ct,void * data)809 static int ctnetlink_filter_match(struct nf_conn *ct, void *data)
810 {
811 	struct ctnetlink_filter *filter = data;
812 
813 	if (filter == NULL)
814 		return 1;
815 
816 #ifdef CONFIG_NF_CONNTRACK_MARK
817 	if ((ct->mark & filter->mark.mask) == filter->mark.val)
818 		return 1;
819 #endif
820 
821 	return 0;
822 }
823 
824 static int
ctnetlink_dump_table(struct sk_buff * skb,struct netlink_callback * cb)825 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
826 {
827 	struct net *net = sock_net(skb->sk);
828 	struct nf_conn *ct, *last;
829 	struct nf_conntrack_tuple_hash *h;
830 	struct hlist_nulls_node *n;
831 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
832 	u_int8_t l3proto = nfmsg->nfgen_family;
833 	struct nf_conn *nf_ct_evict[8];
834 	int res, i;
835 	spinlock_t *lockp;
836 
837 	last = (struct nf_conn *)cb->args[1];
838 	i = 0;
839 
840 	local_bh_disable();
841 	for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
842 restart:
843 		while (i) {
844 			i--;
845 			if (nf_ct_should_gc(nf_ct_evict[i]))
846 				nf_ct_kill(nf_ct_evict[i]);
847 			nf_ct_put(nf_ct_evict[i]);
848 		}
849 
850 		lockp = &nf_conntrack_locks[cb->args[0] % CONNTRACK_LOCKS];
851 		nf_conntrack_lock(lockp);
852 		if (cb->args[0] >= nf_conntrack_htable_size) {
853 			spin_unlock(lockp);
854 			goto out;
855 		}
856 		hlist_nulls_for_each_entry(h, n, &nf_conntrack_hash[cb->args[0]],
857 					   hnnode) {
858 			if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
859 				continue;
860 			ct = nf_ct_tuplehash_to_ctrack(h);
861 			if (nf_ct_is_expired(ct)) {
862 				if (i < ARRAY_SIZE(nf_ct_evict) &&
863 				    atomic_inc_not_zero(&ct->ct_general.use))
864 					nf_ct_evict[i++] = ct;
865 				continue;
866 			}
867 
868 			if (!net_eq(net, nf_ct_net(ct)))
869 				continue;
870 
871 			/* Dump entries of a given L3 protocol number.
872 			 * If it is not specified, ie. l3proto == 0,
873 			 * then dump everything. */
874 			if (l3proto && nf_ct_l3num(ct) != l3proto)
875 				continue;
876 			if (cb->args[1]) {
877 				if (ct != last)
878 					continue;
879 				cb->args[1] = 0;
880 			}
881 			if (!ctnetlink_filter_match(ct, cb->data))
882 				continue;
883 
884 			rcu_read_lock();
885 			res =
886 			ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
887 					    cb->nlh->nlmsg_seq,
888 					    NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
889 					    ct);
890 			rcu_read_unlock();
891 			if (res < 0) {
892 				nf_conntrack_get(&ct->ct_general);
893 				cb->args[1] = (unsigned long)ct;
894 				spin_unlock(lockp);
895 				goto out;
896 			}
897 		}
898 		spin_unlock(lockp);
899 		if (cb->args[1]) {
900 			cb->args[1] = 0;
901 			goto restart;
902 		}
903 	}
904 out:
905 	local_bh_enable();
906 	if (last) {
907 		/* nf ct hash resize happened, now clear the leftover. */
908 		if ((struct nf_conn *)cb->args[1] == last)
909 			cb->args[1] = 0;
910 
911 		nf_ct_put(last);
912 	}
913 
914 	while (i) {
915 		i--;
916 		if (nf_ct_should_gc(nf_ct_evict[i]))
917 			nf_ct_kill(nf_ct_evict[i]);
918 		nf_ct_put(nf_ct_evict[i]);
919 	}
920 
921 	return skb->len;
922 }
923 
ctnetlink_parse_tuple_ip(struct nlattr * attr,struct nf_conntrack_tuple * tuple)924 static int ctnetlink_parse_tuple_ip(struct nlattr *attr,
925 				    struct nf_conntrack_tuple *tuple)
926 {
927 	struct nlattr *tb[CTA_IP_MAX+1];
928 	struct nf_conntrack_l3proto *l3proto;
929 	int ret = 0;
930 
931 	ret = nla_parse_nested(tb, CTA_IP_MAX, attr, NULL, NULL);
932 	if (ret < 0)
933 		return ret;
934 
935 	rcu_read_lock();
936 	l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
937 
938 	if (likely(l3proto->nlattr_to_tuple)) {
939 		ret = nla_validate_nested(attr, CTA_IP_MAX,
940 					  l3proto->nla_policy, NULL);
941 		if (ret == 0)
942 			ret = l3proto->nlattr_to_tuple(tb, tuple);
943 	}
944 
945 	rcu_read_unlock();
946 
947 	return ret;
948 }
949 
950 static const struct nla_policy proto_nla_policy[CTA_PROTO_MAX+1] = {
951 	[CTA_PROTO_NUM]	= { .type = NLA_U8 },
952 };
953 
ctnetlink_parse_tuple_proto(struct nlattr * attr,struct nf_conntrack_tuple * tuple)954 static int ctnetlink_parse_tuple_proto(struct nlattr *attr,
955 				       struct nf_conntrack_tuple *tuple)
956 {
957 	const struct nf_conntrack_l4proto *l4proto;
958 	struct nlattr *tb[CTA_PROTO_MAX+1];
959 	int ret = 0;
960 
961 	ret = nla_parse_nested(tb, CTA_PROTO_MAX, attr, proto_nla_policy,
962 			       NULL);
963 	if (ret < 0)
964 		return ret;
965 
966 	if (!tb[CTA_PROTO_NUM])
967 		return -EINVAL;
968 	tuple->dst.protonum = nla_get_u8(tb[CTA_PROTO_NUM]);
969 
970 	rcu_read_lock();
971 	l4proto = __nf_ct_l4proto_find(tuple->src.l3num, tuple->dst.protonum);
972 
973 	if (likely(l4proto->nlattr_to_tuple)) {
974 		ret = nla_validate_nested(attr, CTA_PROTO_MAX,
975 					  l4proto->nla_policy, NULL);
976 		if (ret == 0)
977 			ret = l4proto->nlattr_to_tuple(tb, tuple);
978 	}
979 
980 	rcu_read_unlock();
981 
982 	return ret;
983 }
984 
985 static int
ctnetlink_parse_zone(const struct nlattr * attr,struct nf_conntrack_zone * zone)986 ctnetlink_parse_zone(const struct nlattr *attr,
987 		     struct nf_conntrack_zone *zone)
988 {
989 	nf_ct_zone_init(zone, NF_CT_DEFAULT_ZONE_ID,
990 			NF_CT_DEFAULT_ZONE_DIR, 0);
991 #ifdef CONFIG_NF_CONNTRACK_ZONES
992 	if (attr)
993 		zone->id = ntohs(nla_get_be16(attr));
994 #else
995 	if (attr)
996 		return -EOPNOTSUPP;
997 #endif
998 	return 0;
999 }
1000 
1001 static int
ctnetlink_parse_tuple_zone(struct nlattr * attr,enum ctattr_type type,struct nf_conntrack_zone * zone)1002 ctnetlink_parse_tuple_zone(struct nlattr *attr, enum ctattr_type type,
1003 			   struct nf_conntrack_zone *zone)
1004 {
1005 	int ret;
1006 
1007 	if (zone->id != NF_CT_DEFAULT_ZONE_ID)
1008 		return -EINVAL;
1009 
1010 	ret = ctnetlink_parse_zone(attr, zone);
1011 	if (ret < 0)
1012 		return ret;
1013 
1014 	if (type == CTA_TUPLE_REPLY)
1015 		zone->dir = NF_CT_ZONE_DIR_REPL;
1016 	else
1017 		zone->dir = NF_CT_ZONE_DIR_ORIG;
1018 
1019 	return 0;
1020 }
1021 
1022 static const struct nla_policy tuple_nla_policy[CTA_TUPLE_MAX+1] = {
1023 	[CTA_TUPLE_IP]		= { .type = NLA_NESTED },
1024 	[CTA_TUPLE_PROTO]	= { .type = NLA_NESTED },
1025 	[CTA_TUPLE_ZONE]	= { .type = NLA_U16 },
1026 };
1027 
1028 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)1029 ctnetlink_parse_tuple(const struct nlattr * const cda[],
1030 		      struct nf_conntrack_tuple *tuple, u32 type,
1031 		      u_int8_t l3num, struct nf_conntrack_zone *zone)
1032 {
1033 	struct nlattr *tb[CTA_TUPLE_MAX+1];
1034 	int err;
1035 
1036 	memset(tuple, 0, sizeof(*tuple));
1037 
1038 	err = nla_parse_nested(tb, CTA_TUPLE_MAX, cda[type], tuple_nla_policy,
1039 			       NULL);
1040 	if (err < 0)
1041 		return err;
1042 
1043 	if (!tb[CTA_TUPLE_IP])
1044 		return -EINVAL;
1045 
1046 	tuple->src.l3num = l3num;
1047 
1048 	err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP], tuple);
1049 	if (err < 0)
1050 		return err;
1051 
1052 	if (!tb[CTA_TUPLE_PROTO])
1053 		return -EINVAL;
1054 
1055 	err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO], tuple);
1056 	if (err < 0)
1057 		return err;
1058 
1059 	if (tb[CTA_TUPLE_ZONE]) {
1060 		if (!zone)
1061 			return -EINVAL;
1062 
1063 		err = ctnetlink_parse_tuple_zone(tb[CTA_TUPLE_ZONE],
1064 						 type, zone);
1065 		if (err < 0)
1066 			return err;
1067 	}
1068 
1069 	/* orig and expect tuples get DIR_ORIGINAL */
1070 	if (type == CTA_TUPLE_REPLY)
1071 		tuple->dst.dir = IP_CT_DIR_REPLY;
1072 	else
1073 		tuple->dst.dir = IP_CT_DIR_ORIGINAL;
1074 
1075 	return 0;
1076 }
1077 
1078 static const struct nla_policy help_nla_policy[CTA_HELP_MAX+1] = {
1079 	[CTA_HELP_NAME]		= { .type = NLA_NUL_STRING,
1080 				    .len = NF_CT_HELPER_NAME_LEN - 1 },
1081 };
1082 
ctnetlink_parse_help(const struct nlattr * attr,char ** helper_name,struct nlattr ** helpinfo)1083 static int ctnetlink_parse_help(const struct nlattr *attr, char **helper_name,
1084 				struct nlattr **helpinfo)
1085 {
1086 	int err;
1087 	struct nlattr *tb[CTA_HELP_MAX+1];
1088 
1089 	err = nla_parse_nested(tb, CTA_HELP_MAX, attr, help_nla_policy, NULL);
1090 	if (err < 0)
1091 		return err;
1092 
1093 	if (!tb[CTA_HELP_NAME])
1094 		return -EINVAL;
1095 
1096 	*helper_name = nla_data(tb[CTA_HELP_NAME]);
1097 
1098 	if (tb[CTA_HELP_INFO])
1099 		*helpinfo = tb[CTA_HELP_INFO];
1100 
1101 	return 0;
1102 }
1103 
1104 static const struct nla_policy ct_nla_policy[CTA_MAX+1] = {
1105 	[CTA_TUPLE_ORIG]	= { .type = NLA_NESTED },
1106 	[CTA_TUPLE_REPLY]	= { .type = NLA_NESTED },
1107 	[CTA_STATUS] 		= { .type = NLA_U32 },
1108 	[CTA_PROTOINFO]		= { .type = NLA_NESTED },
1109 	[CTA_HELP]		= { .type = NLA_NESTED },
1110 	[CTA_NAT_SRC]		= { .type = NLA_NESTED },
1111 	[CTA_TIMEOUT] 		= { .type = NLA_U32 },
1112 	[CTA_MARK]		= { .type = NLA_U32 },
1113 	[CTA_ID]		= { .type = NLA_U32 },
1114 	[CTA_NAT_DST]		= { .type = NLA_NESTED },
1115 	[CTA_TUPLE_MASTER]	= { .type = NLA_NESTED },
1116 	[CTA_NAT_SEQ_ADJ_ORIG]  = { .type = NLA_NESTED },
1117 	[CTA_NAT_SEQ_ADJ_REPLY] = { .type = NLA_NESTED },
1118 	[CTA_ZONE]		= { .type = NLA_U16 },
1119 	[CTA_MARK_MASK]		= { .type = NLA_U32 },
1120 	[CTA_LABELS]		= { .type = NLA_BINARY,
1121 				    .len = NF_CT_LABELS_MAX_SIZE },
1122 	[CTA_LABELS_MASK]	= { .type = NLA_BINARY,
1123 				    .len = NF_CT_LABELS_MAX_SIZE },
1124 };
1125 
ctnetlink_flush_conntrack(struct net * net,const struct nlattr * const cda[],u32 portid,int report)1126 static int ctnetlink_flush_conntrack(struct net *net,
1127 				     const struct nlattr * const cda[],
1128 				     u32 portid, int report)
1129 {
1130 	struct ctnetlink_filter *filter = NULL;
1131 
1132 	if (cda[CTA_MARK] && cda[CTA_MARK_MASK]) {
1133 		filter = ctnetlink_alloc_filter(cda);
1134 		if (IS_ERR(filter))
1135 			return PTR_ERR(filter);
1136 	}
1137 
1138 	nf_ct_iterate_cleanup_net(net, ctnetlink_filter_match, filter,
1139 				  portid, report);
1140 	kfree(filter);
1141 
1142 	return 0;
1143 }
1144 
ctnetlink_del_conntrack(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)1145 static int ctnetlink_del_conntrack(struct net *net, struct sock *ctnl,
1146 				   struct sk_buff *skb,
1147 				   const struct nlmsghdr *nlh,
1148 				   const struct nlattr * const cda[],
1149 				   struct netlink_ext_ack *extack)
1150 {
1151 	struct nf_conntrack_tuple_hash *h;
1152 	struct nf_conntrack_tuple tuple;
1153 	struct nf_conn *ct;
1154 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1155 	u_int8_t u3 = nfmsg->nfgen_family;
1156 	struct nf_conntrack_zone zone;
1157 	int err;
1158 
1159 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1160 	if (err < 0)
1161 		return err;
1162 
1163 	if (cda[CTA_TUPLE_ORIG])
1164 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG,
1165 					    u3, &zone);
1166 	else if (cda[CTA_TUPLE_REPLY])
1167 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY,
1168 					    u3, &zone);
1169 	else {
1170 		return ctnetlink_flush_conntrack(net, cda,
1171 						 NETLINK_CB(skb).portid,
1172 						 nlmsg_report(nlh));
1173 	}
1174 
1175 	if (err < 0)
1176 		return err;
1177 
1178 	h = nf_conntrack_find_get(net, &zone, &tuple);
1179 	if (!h)
1180 		return -ENOENT;
1181 
1182 	ct = nf_ct_tuplehash_to_ctrack(h);
1183 
1184 	if (cda[CTA_ID]) {
1185 		__be32 id = nla_get_be32(cda[CTA_ID]);
1186 
1187 		if (id != (__force __be32)nf_ct_get_id(ct)) {
1188 			nf_ct_put(ct);
1189 			return -ENOENT;
1190 		}
1191 	}
1192 
1193 	nf_ct_delete(ct, NETLINK_CB(skb).portid, nlmsg_report(nlh));
1194 	nf_ct_put(ct);
1195 
1196 	return 0;
1197 }
1198 
ctnetlink_get_conntrack(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)1199 static int ctnetlink_get_conntrack(struct net *net, struct sock *ctnl,
1200 				   struct sk_buff *skb,
1201 				   const struct nlmsghdr *nlh,
1202 				   const struct nlattr * const cda[],
1203 				   struct netlink_ext_ack *extack)
1204 {
1205 	struct nf_conntrack_tuple_hash *h;
1206 	struct nf_conntrack_tuple tuple;
1207 	struct nf_conn *ct;
1208 	struct sk_buff *skb2 = NULL;
1209 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1210 	u_int8_t u3 = nfmsg->nfgen_family;
1211 	struct nf_conntrack_zone zone;
1212 	int err;
1213 
1214 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
1215 		struct netlink_dump_control c = {
1216 			.start = ctnetlink_start,
1217 			.dump = ctnetlink_dump_table,
1218 			.done = ctnetlink_done,
1219 			.data = (void *)cda,
1220 		};
1221 
1222 		return netlink_dump_start(ctnl, skb, nlh, &c);
1223 	}
1224 
1225 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1226 	if (err < 0)
1227 		return err;
1228 
1229 	if (cda[CTA_TUPLE_ORIG])
1230 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG,
1231 					    u3, &zone);
1232 	else if (cda[CTA_TUPLE_REPLY])
1233 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY,
1234 					    u3, &zone);
1235 	else
1236 		return -EINVAL;
1237 
1238 	if (err < 0)
1239 		return err;
1240 
1241 	h = nf_conntrack_find_get(net, &zone, &tuple);
1242 	if (!h)
1243 		return -ENOENT;
1244 
1245 	ct = nf_ct_tuplehash_to_ctrack(h);
1246 
1247 	err = -ENOMEM;
1248 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
1249 	if (skb2 == NULL) {
1250 		nf_ct_put(ct);
1251 		return -ENOMEM;
1252 	}
1253 
1254 	rcu_read_lock();
1255 	err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).portid, nlh->nlmsg_seq,
1256 				  NFNL_MSG_TYPE(nlh->nlmsg_type), ct);
1257 	rcu_read_unlock();
1258 	nf_ct_put(ct);
1259 	if (err <= 0)
1260 		goto free;
1261 
1262 	err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT);
1263 	if (err < 0)
1264 		goto out;
1265 
1266 	return 0;
1267 
1268 free:
1269 	kfree_skb(skb2);
1270 out:
1271 	/* this avoids a loop in nfnetlink. */
1272 	return err == -EAGAIN ? -ENOBUFS : err;
1273 }
1274 
ctnetlink_done_list(struct netlink_callback * cb)1275 static int ctnetlink_done_list(struct netlink_callback *cb)
1276 {
1277 	if (cb->args[1])
1278 		nf_ct_put((struct nf_conn *)cb->args[1]);
1279 	return 0;
1280 }
1281 
1282 static int
ctnetlink_dump_list(struct sk_buff * skb,struct netlink_callback * cb,bool dying)1283 ctnetlink_dump_list(struct sk_buff *skb, struct netlink_callback *cb, bool dying)
1284 {
1285 	struct nf_conn *ct, *last;
1286 	struct nf_conntrack_tuple_hash *h;
1287 	struct hlist_nulls_node *n;
1288 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
1289 	u_int8_t l3proto = nfmsg->nfgen_family;
1290 	int res;
1291 	int cpu;
1292 	struct hlist_nulls_head *list;
1293 	struct net *net = sock_net(skb->sk);
1294 
1295 	if (cb->args[2])
1296 		return 0;
1297 
1298 	last = (struct nf_conn *)cb->args[1];
1299 
1300 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
1301 		struct ct_pcpu *pcpu;
1302 
1303 		if (!cpu_possible(cpu))
1304 			continue;
1305 
1306 		pcpu = per_cpu_ptr(net->ct.pcpu_lists, cpu);
1307 		spin_lock_bh(&pcpu->lock);
1308 		list = dying ? &pcpu->dying : &pcpu->unconfirmed;
1309 restart:
1310 		hlist_nulls_for_each_entry(h, n, list, hnnode) {
1311 			ct = nf_ct_tuplehash_to_ctrack(h);
1312 			if (l3proto && nf_ct_l3num(ct) != l3proto)
1313 				continue;
1314 			if (cb->args[1]) {
1315 				if (ct != last)
1316 					continue;
1317 				cb->args[1] = 0;
1318 			}
1319 			rcu_read_lock();
1320 			res = ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).portid,
1321 						  cb->nlh->nlmsg_seq,
1322 						  NFNL_MSG_TYPE(cb->nlh->nlmsg_type),
1323 						  ct);
1324 			rcu_read_unlock();
1325 			if (res < 0) {
1326 				if (!atomic_inc_not_zero(&ct->ct_general.use))
1327 					continue;
1328 				cb->args[0] = cpu;
1329 				cb->args[1] = (unsigned long)ct;
1330 				spin_unlock_bh(&pcpu->lock);
1331 				goto out;
1332 			}
1333 		}
1334 		if (cb->args[1]) {
1335 			cb->args[1] = 0;
1336 			goto restart;
1337 		}
1338 		spin_unlock_bh(&pcpu->lock);
1339 	}
1340 	cb->args[2] = 1;
1341 out:
1342 	if (last)
1343 		nf_ct_put(last);
1344 
1345 	return skb->len;
1346 }
1347 
1348 static int
ctnetlink_dump_dying(struct sk_buff * skb,struct netlink_callback * cb)1349 ctnetlink_dump_dying(struct sk_buff *skb, struct netlink_callback *cb)
1350 {
1351 	return ctnetlink_dump_list(skb, cb, true);
1352 }
1353 
ctnetlink_get_ct_dying(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)1354 static int ctnetlink_get_ct_dying(struct net *net, struct sock *ctnl,
1355 				  struct sk_buff *skb,
1356 				  const struct nlmsghdr *nlh,
1357 				  const struct nlattr * const cda[],
1358 				  struct netlink_ext_ack *extack)
1359 {
1360 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
1361 		struct netlink_dump_control c = {
1362 			.dump = ctnetlink_dump_dying,
1363 			.done = ctnetlink_done_list,
1364 		};
1365 		return netlink_dump_start(ctnl, skb, nlh, &c);
1366 	}
1367 
1368 	return -EOPNOTSUPP;
1369 }
1370 
1371 static int
ctnetlink_dump_unconfirmed(struct sk_buff * skb,struct netlink_callback * cb)1372 ctnetlink_dump_unconfirmed(struct sk_buff *skb, struct netlink_callback *cb)
1373 {
1374 	return ctnetlink_dump_list(skb, cb, false);
1375 }
1376 
ctnetlink_get_ct_unconfirmed(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)1377 static int ctnetlink_get_ct_unconfirmed(struct net *net, struct sock *ctnl,
1378 					struct sk_buff *skb,
1379 					const struct nlmsghdr *nlh,
1380 					const struct nlattr * const cda[],
1381 					struct netlink_ext_ack *extack)
1382 {
1383 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
1384 		struct netlink_dump_control c = {
1385 			.dump = ctnetlink_dump_unconfirmed,
1386 			.done = ctnetlink_done_list,
1387 		};
1388 		return netlink_dump_start(ctnl, skb, nlh, &c);
1389 	}
1390 
1391 	return -EOPNOTSUPP;
1392 }
1393 
1394 #ifdef CONFIG_NF_NAT_NEEDED
1395 static int
ctnetlink_parse_nat_setup(struct nf_conn * ct,enum nf_nat_manip_type manip,const struct nlattr * attr)1396 ctnetlink_parse_nat_setup(struct nf_conn *ct,
1397 			  enum nf_nat_manip_type manip,
1398 			  const struct nlattr *attr)
1399 {
1400 	typeof(nfnetlink_parse_nat_setup_hook) parse_nat_setup;
1401 	int err;
1402 
1403 	parse_nat_setup = rcu_dereference(nfnetlink_parse_nat_setup_hook);
1404 	if (!parse_nat_setup) {
1405 #ifdef CONFIG_MODULES
1406 		rcu_read_unlock();
1407 		nfnl_unlock(NFNL_SUBSYS_CTNETLINK);
1408 		if (request_module("nf-nat") < 0) {
1409 			nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1410 			rcu_read_lock();
1411 			return -EOPNOTSUPP;
1412 		}
1413 		nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1414 		rcu_read_lock();
1415 		if (nfnetlink_parse_nat_setup_hook)
1416 			return -EAGAIN;
1417 #endif
1418 		return -EOPNOTSUPP;
1419 	}
1420 
1421 	err = parse_nat_setup(ct, manip, attr);
1422 	if (err == -EAGAIN) {
1423 #ifdef CONFIG_MODULES
1424 		rcu_read_unlock();
1425 		nfnl_unlock(NFNL_SUBSYS_CTNETLINK);
1426 		if (request_module("nf-nat-%u", nf_ct_l3num(ct)) < 0) {
1427 			nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1428 			rcu_read_lock();
1429 			return -EOPNOTSUPP;
1430 		}
1431 		nfnl_lock(NFNL_SUBSYS_CTNETLINK);
1432 		rcu_read_lock();
1433 #else
1434 		err = -EOPNOTSUPP;
1435 #endif
1436 	}
1437 	return err;
1438 }
1439 #endif
1440 
1441 static void
__ctnetlink_change_status(struct nf_conn * ct,unsigned long on,unsigned long off)1442 __ctnetlink_change_status(struct nf_conn *ct, unsigned long on,
1443 			  unsigned long off)
1444 {
1445 	unsigned int bit;
1446 
1447 	/* Ignore these unchangable bits */
1448 	on &= ~IPS_UNCHANGEABLE_MASK;
1449 	off &= ~IPS_UNCHANGEABLE_MASK;
1450 
1451 	for (bit = 0; bit < __IPS_MAX_BIT; bit++) {
1452 		if (on & (1 << bit))
1453 			set_bit(bit, &ct->status);
1454 		else if (off & (1 << bit))
1455 			clear_bit(bit, &ct->status);
1456 	}
1457 }
1458 
1459 static int
ctnetlink_change_status(struct nf_conn * ct,const struct nlattr * const cda[])1460 ctnetlink_change_status(struct nf_conn *ct, const struct nlattr * const cda[])
1461 {
1462 	unsigned long d;
1463 	unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
1464 	d = ct->status ^ status;
1465 
1466 	if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
1467 		/* unchangeable */
1468 		return -EBUSY;
1469 
1470 	if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
1471 		/* SEEN_REPLY bit can only be set */
1472 		return -EBUSY;
1473 
1474 	if (d & IPS_ASSURED && !(status & IPS_ASSURED))
1475 		/* ASSURED bit can only be set */
1476 		return -EBUSY;
1477 
1478 	__ctnetlink_change_status(ct, status, 0);
1479 	return 0;
1480 }
1481 
1482 static int
ctnetlink_setup_nat(struct nf_conn * ct,const struct nlattr * const cda[])1483 ctnetlink_setup_nat(struct nf_conn *ct, const struct nlattr * const cda[])
1484 {
1485 #ifdef CONFIG_NF_NAT_NEEDED
1486 	int ret;
1487 
1488 	if (!cda[CTA_NAT_DST] && !cda[CTA_NAT_SRC])
1489 		return 0;
1490 
1491 	ret = ctnetlink_parse_nat_setup(ct, NF_NAT_MANIP_DST,
1492 					cda[CTA_NAT_DST]);
1493 	if (ret < 0)
1494 		return ret;
1495 
1496 	ret = ctnetlink_parse_nat_setup(ct, NF_NAT_MANIP_SRC,
1497 					cda[CTA_NAT_SRC]);
1498 	return ret;
1499 #else
1500 	if (!cda[CTA_NAT_DST] && !cda[CTA_NAT_SRC])
1501 		return 0;
1502 	return -EOPNOTSUPP;
1503 #endif
1504 }
1505 
ctnetlink_change_helper(struct nf_conn * ct,const struct nlattr * const cda[])1506 static int ctnetlink_change_helper(struct nf_conn *ct,
1507 				   const struct nlattr * const cda[])
1508 {
1509 	struct nf_conntrack_helper *helper;
1510 	struct nf_conn_help *help = nfct_help(ct);
1511 	char *helpname = NULL;
1512 	struct nlattr *helpinfo = NULL;
1513 	int err;
1514 
1515 	err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
1516 	if (err < 0)
1517 		return err;
1518 
1519 	/* don't change helper of sibling connections */
1520 	if (ct->master) {
1521 		/* If we try to change the helper to the same thing twice,
1522 		 * treat the second attempt as a no-op instead of returning
1523 		 * an error.
1524 		 */
1525 		err = -EBUSY;
1526 		if (help) {
1527 			rcu_read_lock();
1528 			helper = rcu_dereference(help->helper);
1529 			if (helper && !strcmp(helper->name, helpname))
1530 				err = 0;
1531 			rcu_read_unlock();
1532 		}
1533 
1534 		return err;
1535 	}
1536 
1537 	if (!strcmp(helpname, "")) {
1538 		if (help && help->helper) {
1539 			/* we had a helper before ... */
1540 			nf_ct_remove_expectations(ct);
1541 			RCU_INIT_POINTER(help->helper, NULL);
1542 		}
1543 
1544 		return 0;
1545 	}
1546 
1547 	rcu_read_lock();
1548 	helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
1549 					    nf_ct_protonum(ct));
1550 	if (helper == NULL) {
1551 		rcu_read_unlock();
1552 		return -EOPNOTSUPP;
1553 	}
1554 
1555 	if (help) {
1556 		if (help->helper == helper) {
1557 			/* update private helper data if allowed. */
1558 			if (helper->from_nlattr)
1559 				helper->from_nlattr(helpinfo, ct);
1560 			err = 0;
1561 		} else
1562 			err = -EBUSY;
1563 	} else {
1564 		/* we cannot set a helper for an existing conntrack */
1565 		err = -EOPNOTSUPP;
1566 	}
1567 
1568 	rcu_read_unlock();
1569 	return err;
1570 }
1571 
ctnetlink_change_timeout(struct nf_conn * ct,const struct nlattr * const cda[])1572 static int ctnetlink_change_timeout(struct nf_conn *ct,
1573 				    const struct nlattr * const cda[])
1574 {
1575 	u_int32_t timeout = ntohl(nla_get_be32(cda[CTA_TIMEOUT]));
1576 
1577 	ct->timeout = nfct_time_stamp + timeout * HZ;
1578 
1579 	if (test_bit(IPS_DYING_BIT, &ct->status))
1580 		return -ETIME;
1581 
1582 	return 0;
1583 }
1584 
1585 static const struct nla_policy protoinfo_policy[CTA_PROTOINFO_MAX+1] = {
1586 	[CTA_PROTOINFO_TCP]	= { .type = NLA_NESTED },
1587 	[CTA_PROTOINFO_DCCP]	= { .type = NLA_NESTED },
1588 	[CTA_PROTOINFO_SCTP]	= { .type = NLA_NESTED },
1589 };
1590 
ctnetlink_change_protoinfo(struct nf_conn * ct,const struct nlattr * const cda[])1591 static int ctnetlink_change_protoinfo(struct nf_conn *ct,
1592 				      const struct nlattr * const cda[])
1593 {
1594 	const struct nlattr *attr = cda[CTA_PROTOINFO];
1595 	const struct nf_conntrack_l4proto *l4proto;
1596 	struct nlattr *tb[CTA_PROTOINFO_MAX+1];
1597 	int err = 0;
1598 
1599 	err = nla_parse_nested(tb, CTA_PROTOINFO_MAX, attr, protoinfo_policy,
1600 			       NULL);
1601 	if (err < 0)
1602 		return err;
1603 
1604 	rcu_read_lock();
1605 	l4proto = __nf_ct_l4proto_find(nf_ct_l3num(ct), nf_ct_protonum(ct));
1606 	if (l4proto->from_nlattr)
1607 		err = l4proto->from_nlattr(tb, ct);
1608 	rcu_read_unlock();
1609 
1610 	return err;
1611 }
1612 
1613 static const struct nla_policy seqadj_policy[CTA_SEQADJ_MAX+1] = {
1614 	[CTA_SEQADJ_CORRECTION_POS]	= { .type = NLA_U32 },
1615 	[CTA_SEQADJ_OFFSET_BEFORE]	= { .type = NLA_U32 },
1616 	[CTA_SEQADJ_OFFSET_AFTER]	= { .type = NLA_U32 },
1617 };
1618 
change_seq_adj(struct nf_ct_seqadj * seq,const struct nlattr * const attr)1619 static int change_seq_adj(struct nf_ct_seqadj *seq,
1620 			  const struct nlattr * const attr)
1621 {
1622 	int err;
1623 	struct nlattr *cda[CTA_SEQADJ_MAX+1];
1624 
1625 	err = nla_parse_nested(cda, CTA_SEQADJ_MAX, attr, seqadj_policy, NULL);
1626 	if (err < 0)
1627 		return err;
1628 
1629 	if (!cda[CTA_SEQADJ_CORRECTION_POS])
1630 		return -EINVAL;
1631 
1632 	seq->correction_pos =
1633 		ntohl(nla_get_be32(cda[CTA_SEQADJ_CORRECTION_POS]));
1634 
1635 	if (!cda[CTA_SEQADJ_OFFSET_BEFORE])
1636 		return -EINVAL;
1637 
1638 	seq->offset_before =
1639 		ntohl(nla_get_be32(cda[CTA_SEQADJ_OFFSET_BEFORE]));
1640 
1641 	if (!cda[CTA_SEQADJ_OFFSET_AFTER])
1642 		return -EINVAL;
1643 
1644 	seq->offset_after =
1645 		ntohl(nla_get_be32(cda[CTA_SEQADJ_OFFSET_AFTER]));
1646 
1647 	return 0;
1648 }
1649 
1650 static int
ctnetlink_change_seq_adj(struct nf_conn * ct,const struct nlattr * const cda[])1651 ctnetlink_change_seq_adj(struct nf_conn *ct,
1652 			 const struct nlattr * const cda[])
1653 {
1654 	struct nf_conn_seqadj *seqadj = nfct_seqadj(ct);
1655 	int ret = 0;
1656 
1657 	if (!seqadj)
1658 		return 0;
1659 
1660 	spin_lock_bh(&ct->lock);
1661 	if (cda[CTA_SEQ_ADJ_ORIG]) {
1662 		ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_ORIGINAL],
1663 				     cda[CTA_SEQ_ADJ_ORIG]);
1664 		if (ret < 0)
1665 			goto err;
1666 
1667 		set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
1668 	}
1669 
1670 	if (cda[CTA_SEQ_ADJ_REPLY]) {
1671 		ret = change_seq_adj(&seqadj->seq[IP_CT_DIR_REPLY],
1672 				     cda[CTA_SEQ_ADJ_REPLY]);
1673 		if (ret < 0)
1674 			goto err;
1675 
1676 		set_bit(IPS_SEQ_ADJUST_BIT, &ct->status);
1677 	}
1678 
1679 	spin_unlock_bh(&ct->lock);
1680 	return 0;
1681 err:
1682 	spin_unlock_bh(&ct->lock);
1683 	return ret;
1684 }
1685 
1686 static int
ctnetlink_attach_labels(struct nf_conn * ct,const struct nlattr * const cda[])1687 ctnetlink_attach_labels(struct nf_conn *ct, const struct nlattr * const cda[])
1688 {
1689 #ifdef CONFIG_NF_CONNTRACK_LABELS
1690 	size_t len = nla_len(cda[CTA_LABELS]);
1691 	const void *mask = cda[CTA_LABELS_MASK];
1692 
1693 	if (len & (sizeof(u32)-1)) /* must be multiple of u32 */
1694 		return -EINVAL;
1695 
1696 	if (mask) {
1697 		if (nla_len(cda[CTA_LABELS_MASK]) == 0 ||
1698 		    nla_len(cda[CTA_LABELS_MASK]) != len)
1699 			return -EINVAL;
1700 		mask = nla_data(cda[CTA_LABELS_MASK]);
1701 	}
1702 
1703 	len /= sizeof(u32);
1704 
1705 	return nf_connlabels_replace(ct, nla_data(cda[CTA_LABELS]), mask, len);
1706 #else
1707 	return -EOPNOTSUPP;
1708 #endif
1709 }
1710 
1711 static int
ctnetlink_change_conntrack(struct nf_conn * ct,const struct nlattr * const cda[])1712 ctnetlink_change_conntrack(struct nf_conn *ct,
1713 			   const struct nlattr * const cda[])
1714 {
1715 	int err;
1716 
1717 	/* only allow NAT changes and master assignation for new conntracks */
1718 	if (cda[CTA_NAT_SRC] || cda[CTA_NAT_DST] || cda[CTA_TUPLE_MASTER])
1719 		return -EOPNOTSUPP;
1720 
1721 	if (cda[CTA_HELP]) {
1722 		err = ctnetlink_change_helper(ct, cda);
1723 		if (err < 0)
1724 			return err;
1725 	}
1726 
1727 	if (cda[CTA_TIMEOUT]) {
1728 		err = ctnetlink_change_timeout(ct, cda);
1729 		if (err < 0)
1730 			return err;
1731 	}
1732 
1733 	if (cda[CTA_STATUS]) {
1734 		err = ctnetlink_change_status(ct, cda);
1735 		if (err < 0)
1736 			return err;
1737 	}
1738 
1739 	if (cda[CTA_PROTOINFO]) {
1740 		err = ctnetlink_change_protoinfo(ct, cda);
1741 		if (err < 0)
1742 			return err;
1743 	}
1744 
1745 #if defined(CONFIG_NF_CONNTRACK_MARK)
1746 	if (cda[CTA_MARK])
1747 		ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1748 #endif
1749 
1750 	if (cda[CTA_SEQ_ADJ_ORIG] || cda[CTA_SEQ_ADJ_REPLY]) {
1751 		err = ctnetlink_change_seq_adj(ct, cda);
1752 		if (err < 0)
1753 			return err;
1754 	}
1755 
1756 	if (cda[CTA_LABELS]) {
1757 		err = ctnetlink_attach_labels(ct, cda);
1758 		if (err < 0)
1759 			return err;
1760 	}
1761 
1762 	return 0;
1763 }
1764 
1765 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)1766 ctnetlink_create_conntrack(struct net *net,
1767 			   const struct nf_conntrack_zone *zone,
1768 			   const struct nlattr * const cda[],
1769 			   struct nf_conntrack_tuple *otuple,
1770 			   struct nf_conntrack_tuple *rtuple,
1771 			   u8 u3)
1772 {
1773 	struct nf_conn *ct;
1774 	int err = -EINVAL;
1775 	struct nf_conntrack_helper *helper;
1776 	struct nf_conn_tstamp *tstamp;
1777 
1778 	ct = nf_conntrack_alloc(net, zone, otuple, rtuple, GFP_ATOMIC);
1779 	if (IS_ERR(ct))
1780 		return ERR_PTR(-ENOMEM);
1781 
1782 	if (!cda[CTA_TIMEOUT])
1783 		goto err1;
1784 
1785 	ct->timeout = nfct_time_stamp + ntohl(nla_get_be32(cda[CTA_TIMEOUT])) * HZ;
1786 
1787 	rcu_read_lock();
1788  	if (cda[CTA_HELP]) {
1789 		char *helpname = NULL;
1790 		struct nlattr *helpinfo = NULL;
1791 
1792 		err = ctnetlink_parse_help(cda[CTA_HELP], &helpname, &helpinfo);
1793  		if (err < 0)
1794 			goto err2;
1795 
1796 		helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
1797 						    nf_ct_protonum(ct));
1798 		if (helper == NULL) {
1799 			rcu_read_unlock();
1800 #ifdef CONFIG_MODULES
1801 			if (request_module("nfct-helper-%s", helpname) < 0) {
1802 				err = -EOPNOTSUPP;
1803 				goto err1;
1804 			}
1805 
1806 			rcu_read_lock();
1807 			helper = __nf_conntrack_helper_find(helpname,
1808 							    nf_ct_l3num(ct),
1809 							    nf_ct_protonum(ct));
1810 			if (helper) {
1811 				err = -EAGAIN;
1812 				goto err2;
1813 			}
1814 			rcu_read_unlock();
1815 #endif
1816 			err = -EOPNOTSUPP;
1817 			goto err1;
1818 		} else {
1819 			struct nf_conn_help *help;
1820 
1821 			help = nf_ct_helper_ext_add(ct, helper, GFP_ATOMIC);
1822 			if (help == NULL) {
1823 				err = -ENOMEM;
1824 				goto err2;
1825 			}
1826 			/* set private helper data if allowed. */
1827 			if (helper->from_nlattr)
1828 				helper->from_nlattr(helpinfo, ct);
1829 
1830 			/* not in hash table yet so not strictly necessary */
1831 			RCU_INIT_POINTER(help->helper, helper);
1832 		}
1833 	} else {
1834 		/* try an implicit helper assignation */
1835 		err = __nf_ct_try_assign_helper(ct, NULL, GFP_ATOMIC);
1836 		if (err < 0)
1837 			goto err2;
1838 	}
1839 
1840 	err = ctnetlink_setup_nat(ct, cda);
1841 	if (err < 0)
1842 		goto err2;
1843 
1844 	nf_ct_acct_ext_add(ct, GFP_ATOMIC);
1845 	nf_ct_tstamp_ext_add(ct, GFP_ATOMIC);
1846 	nf_ct_ecache_ext_add(ct, 0, 0, GFP_ATOMIC);
1847 	nf_ct_labels_ext_add(ct);
1848 	nfct_seqadj_ext_add(ct);
1849 	nfct_synproxy_ext_add(ct);
1850 
1851 	/* we must add conntrack extensions before confirmation. */
1852 	ct->status |= IPS_CONFIRMED;
1853 
1854 	if (cda[CTA_STATUS]) {
1855 		err = ctnetlink_change_status(ct, cda);
1856 		if (err < 0)
1857 			goto err2;
1858 	}
1859 
1860 	if (cda[CTA_SEQ_ADJ_ORIG] || cda[CTA_SEQ_ADJ_REPLY]) {
1861 		err = ctnetlink_change_seq_adj(ct, cda);
1862 		if (err < 0)
1863 			goto err2;
1864 	}
1865 
1866 	memset(&ct->proto, 0, sizeof(ct->proto));
1867 	if (cda[CTA_PROTOINFO]) {
1868 		err = ctnetlink_change_protoinfo(ct, cda);
1869 		if (err < 0)
1870 			goto err2;
1871 	}
1872 
1873 #if defined(CONFIG_NF_CONNTRACK_MARK)
1874 	if (cda[CTA_MARK])
1875 		ct->mark = ntohl(nla_get_be32(cda[CTA_MARK]));
1876 #endif
1877 
1878 	/* setup master conntrack: this is a confirmed expectation */
1879 	if (cda[CTA_TUPLE_MASTER]) {
1880 		struct nf_conntrack_tuple master;
1881 		struct nf_conntrack_tuple_hash *master_h;
1882 		struct nf_conn *master_ct;
1883 
1884 		err = ctnetlink_parse_tuple(cda, &master, CTA_TUPLE_MASTER,
1885 					    u3, NULL);
1886 		if (err < 0)
1887 			goto err2;
1888 
1889 		master_h = nf_conntrack_find_get(net, zone, &master);
1890 		if (master_h == NULL) {
1891 			err = -ENOENT;
1892 			goto err2;
1893 		}
1894 		master_ct = nf_ct_tuplehash_to_ctrack(master_h);
1895 		__set_bit(IPS_EXPECTED_BIT, &ct->status);
1896 		ct->master = master_ct;
1897 	}
1898 	tstamp = nf_conn_tstamp_find(ct);
1899 	if (tstamp)
1900 		tstamp->start = ktime_get_real_ns();
1901 
1902 	err = nf_conntrack_hash_check_insert(ct);
1903 	if (err < 0)
1904 		goto err2;
1905 
1906 	rcu_read_unlock();
1907 
1908 	return ct;
1909 
1910 err2:
1911 	rcu_read_unlock();
1912 err1:
1913 	nf_conntrack_free(ct);
1914 	return ERR_PTR(err);
1915 }
1916 
ctnetlink_new_conntrack(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)1917 static int ctnetlink_new_conntrack(struct net *net, struct sock *ctnl,
1918 				   struct sk_buff *skb,
1919 				   const struct nlmsghdr *nlh,
1920 				   const struct nlattr * const cda[],
1921 				   struct netlink_ext_ack *extack)
1922 {
1923 	struct nf_conntrack_tuple otuple, rtuple;
1924 	struct nf_conntrack_tuple_hash *h = NULL;
1925 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
1926 	struct nf_conn *ct;
1927 	u_int8_t u3 = nfmsg->nfgen_family;
1928 	struct nf_conntrack_zone zone;
1929 	int err;
1930 
1931 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &zone);
1932 	if (err < 0)
1933 		return err;
1934 
1935 	if (cda[CTA_TUPLE_ORIG]) {
1936 		err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG,
1937 					    u3, &zone);
1938 		if (err < 0)
1939 			return err;
1940 	}
1941 
1942 	if (cda[CTA_TUPLE_REPLY]) {
1943 		err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY,
1944 					    u3, &zone);
1945 		if (err < 0)
1946 			return err;
1947 	}
1948 
1949 	if (cda[CTA_TUPLE_ORIG])
1950 		h = nf_conntrack_find_get(net, &zone, &otuple);
1951 	else if (cda[CTA_TUPLE_REPLY])
1952 		h = nf_conntrack_find_get(net, &zone, &rtuple);
1953 
1954 	if (h == NULL) {
1955 		err = -ENOENT;
1956 		if (nlh->nlmsg_flags & NLM_F_CREATE) {
1957 			enum ip_conntrack_events events;
1958 
1959 			if (!cda[CTA_TUPLE_ORIG] || !cda[CTA_TUPLE_REPLY])
1960 				return -EINVAL;
1961 			if (otuple.dst.protonum != rtuple.dst.protonum)
1962 				return -EINVAL;
1963 
1964 			ct = ctnetlink_create_conntrack(net, &zone, cda, &otuple,
1965 							&rtuple, u3);
1966 			if (IS_ERR(ct))
1967 				return PTR_ERR(ct);
1968 
1969 			err = 0;
1970 			if (test_bit(IPS_EXPECTED_BIT, &ct->status))
1971 				events = 1 << IPCT_RELATED;
1972 			else
1973 				events = 1 << IPCT_NEW;
1974 
1975 			if (cda[CTA_LABELS] &&
1976 			    ctnetlink_attach_labels(ct, cda) == 0)
1977 				events |= (1 << IPCT_LABEL);
1978 
1979 			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
1980 						      (1 << IPCT_ASSURED) |
1981 						      (1 << IPCT_HELPER) |
1982 						      (1 << IPCT_PROTOINFO) |
1983 						      (1 << IPCT_SEQADJ) |
1984 						      (1 << IPCT_MARK) | events,
1985 						      ct, NETLINK_CB(skb).portid,
1986 						      nlmsg_report(nlh));
1987 			nf_ct_put(ct);
1988 		}
1989 
1990 		return err;
1991 	}
1992 	/* implicit 'else' */
1993 
1994 	err = -EEXIST;
1995 	ct = nf_ct_tuplehash_to_ctrack(h);
1996 	if (!(nlh->nlmsg_flags & NLM_F_EXCL)) {
1997 		err = ctnetlink_change_conntrack(ct, cda);
1998 		if (err == 0) {
1999 			nf_conntrack_eventmask_report((1 << IPCT_REPLY) |
2000 						      (1 << IPCT_ASSURED) |
2001 						      (1 << IPCT_HELPER) |
2002 						      (1 << IPCT_LABEL) |
2003 						      (1 << IPCT_PROTOINFO) |
2004 						      (1 << IPCT_SEQADJ) |
2005 						      (1 << IPCT_MARK),
2006 						      ct, NETLINK_CB(skb).portid,
2007 						      nlmsg_report(nlh));
2008 		}
2009 	}
2010 
2011 	nf_ct_put(ct);
2012 	return err;
2013 }
2014 
2015 static int
ctnetlink_ct_stat_cpu_fill_info(struct sk_buff * skb,u32 portid,u32 seq,__u16 cpu,const struct ip_conntrack_stat * st)2016 ctnetlink_ct_stat_cpu_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
2017 				__u16 cpu, const struct ip_conntrack_stat *st)
2018 {
2019 	struct nlmsghdr *nlh;
2020 	struct nfgenmsg *nfmsg;
2021 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
2022 
2023 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK,
2024 			      IPCTNL_MSG_CT_GET_STATS_CPU);
2025 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags);
2026 	if (nlh == NULL)
2027 		goto nlmsg_failure;
2028 
2029 	nfmsg = nlmsg_data(nlh);
2030 	nfmsg->nfgen_family = AF_UNSPEC;
2031 	nfmsg->version      = NFNETLINK_V0;
2032 	nfmsg->res_id	    = htons(cpu);
2033 
2034 	if (nla_put_be32(skb, CTA_STATS_FOUND, htonl(st->found)) ||
2035 	    nla_put_be32(skb, CTA_STATS_INVALID, htonl(st->invalid)) ||
2036 	    nla_put_be32(skb, CTA_STATS_IGNORE, htonl(st->ignore)) ||
2037 	    nla_put_be32(skb, CTA_STATS_INSERT, htonl(st->insert)) ||
2038 	    nla_put_be32(skb, CTA_STATS_INSERT_FAILED,
2039 				htonl(st->insert_failed)) ||
2040 	    nla_put_be32(skb, CTA_STATS_DROP, htonl(st->drop)) ||
2041 	    nla_put_be32(skb, CTA_STATS_EARLY_DROP, htonl(st->early_drop)) ||
2042 	    nla_put_be32(skb, CTA_STATS_ERROR, htonl(st->error)) ||
2043 	    nla_put_be32(skb, CTA_STATS_SEARCH_RESTART,
2044 				htonl(st->search_restart)))
2045 		goto nla_put_failure;
2046 
2047 	nlmsg_end(skb, nlh);
2048 	return skb->len;
2049 
2050 nla_put_failure:
2051 nlmsg_failure:
2052 	nlmsg_cancel(skb, nlh);
2053 	return -1;
2054 }
2055 
2056 static int
ctnetlink_ct_stat_cpu_dump(struct sk_buff * skb,struct netlink_callback * cb)2057 ctnetlink_ct_stat_cpu_dump(struct sk_buff *skb, struct netlink_callback *cb)
2058 {
2059 	int cpu;
2060 	struct net *net = sock_net(skb->sk);
2061 
2062 	if (cb->args[0] == nr_cpu_ids)
2063 		return 0;
2064 
2065 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
2066 		const struct ip_conntrack_stat *st;
2067 
2068 		if (!cpu_possible(cpu))
2069 			continue;
2070 
2071 		st = per_cpu_ptr(net->ct.stat, cpu);
2072 		if (ctnetlink_ct_stat_cpu_fill_info(skb,
2073 						    NETLINK_CB(cb->skb).portid,
2074 						    cb->nlh->nlmsg_seq,
2075 						    cpu, st) < 0)
2076 				break;
2077 	}
2078 	cb->args[0] = cpu;
2079 
2080 	return skb->len;
2081 }
2082 
ctnetlink_stat_ct_cpu(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)2083 static int ctnetlink_stat_ct_cpu(struct net *net, struct sock *ctnl,
2084 				 struct sk_buff *skb,
2085 				 const struct nlmsghdr *nlh,
2086 				 const struct nlattr * const cda[],
2087 				 struct netlink_ext_ack *extack)
2088 {
2089 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
2090 		struct netlink_dump_control c = {
2091 			.dump = ctnetlink_ct_stat_cpu_dump,
2092 		};
2093 		return netlink_dump_start(ctnl, skb, nlh, &c);
2094 	}
2095 
2096 	return 0;
2097 }
2098 
2099 static int
ctnetlink_stat_ct_fill_info(struct sk_buff * skb,u32 portid,u32 seq,u32 type,struct net * net)2100 ctnetlink_stat_ct_fill_info(struct sk_buff *skb, u32 portid, u32 seq, u32 type,
2101 			    struct net *net)
2102 {
2103 	struct nlmsghdr *nlh;
2104 	struct nfgenmsg *nfmsg;
2105 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
2106 	unsigned int nr_conntracks = atomic_read(&net->ct.count);
2107 
2108 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK, IPCTNL_MSG_CT_GET_STATS);
2109 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags);
2110 	if (nlh == NULL)
2111 		goto nlmsg_failure;
2112 
2113 	nfmsg = nlmsg_data(nlh);
2114 	nfmsg->nfgen_family = AF_UNSPEC;
2115 	nfmsg->version      = NFNETLINK_V0;
2116 	nfmsg->res_id	    = 0;
2117 
2118 	if (nla_put_be32(skb, CTA_STATS_GLOBAL_ENTRIES, htonl(nr_conntracks)))
2119 		goto nla_put_failure;
2120 
2121 	nlmsg_end(skb, nlh);
2122 	return skb->len;
2123 
2124 nla_put_failure:
2125 nlmsg_failure:
2126 	nlmsg_cancel(skb, nlh);
2127 	return -1;
2128 }
2129 
ctnetlink_stat_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)2130 static int ctnetlink_stat_ct(struct net *net, struct sock *ctnl,
2131 			     struct sk_buff *skb, const struct nlmsghdr *nlh,
2132 			     const struct nlattr * const cda[],
2133 			     struct netlink_ext_ack *extack)
2134 {
2135 	struct sk_buff *skb2;
2136 	int err;
2137 
2138 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
2139 	if (skb2 == NULL)
2140 		return -ENOMEM;
2141 
2142 	err = ctnetlink_stat_ct_fill_info(skb2, NETLINK_CB(skb).portid,
2143 					  nlh->nlmsg_seq,
2144 					  NFNL_MSG_TYPE(nlh->nlmsg_type),
2145 					  sock_net(skb->sk));
2146 	if (err <= 0)
2147 		goto free;
2148 
2149 	err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT);
2150 	if (err < 0)
2151 		goto out;
2152 
2153 	return 0;
2154 
2155 free:
2156 	kfree_skb(skb2);
2157 out:
2158 	/* this avoids a loop in nfnetlink. */
2159 	return err == -EAGAIN ? -ENOBUFS : err;
2160 }
2161 
2162 static const struct nla_policy exp_nla_policy[CTA_EXPECT_MAX+1] = {
2163 	[CTA_EXPECT_MASTER]	= { .type = NLA_NESTED },
2164 	[CTA_EXPECT_TUPLE]	= { .type = NLA_NESTED },
2165 	[CTA_EXPECT_MASK]	= { .type = NLA_NESTED },
2166 	[CTA_EXPECT_TIMEOUT]	= { .type = NLA_U32 },
2167 	[CTA_EXPECT_ID]		= { .type = NLA_U32 },
2168 	[CTA_EXPECT_HELP_NAME]	= { .type = NLA_NUL_STRING,
2169 				    .len = NF_CT_HELPER_NAME_LEN - 1 },
2170 	[CTA_EXPECT_ZONE]	= { .type = NLA_U16 },
2171 	[CTA_EXPECT_FLAGS]	= { .type = NLA_U32 },
2172 	[CTA_EXPECT_CLASS]	= { .type = NLA_U32 },
2173 	[CTA_EXPECT_NAT]	= { .type = NLA_NESTED },
2174 	[CTA_EXPECT_FN]		= { .type = NLA_NUL_STRING },
2175 };
2176 
2177 static struct nf_conntrack_expect *
2178 ctnetlink_alloc_expect(const struct nlattr *const cda[], struct nf_conn *ct,
2179 		       struct nf_conntrack_helper *helper,
2180 		       struct nf_conntrack_tuple *tuple,
2181 		       struct nf_conntrack_tuple *mask);
2182 
2183 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
2184 static size_t
ctnetlink_glue_build_size(const struct nf_conn * ct)2185 ctnetlink_glue_build_size(const struct nf_conn *ct)
2186 {
2187 	return 3 * nla_total_size(0) /* CTA_TUPLE_ORIG|REPL|MASTER */
2188 	       + 3 * nla_total_size(0) /* CTA_TUPLE_IP */
2189 	       + 3 * nla_total_size(0) /* CTA_TUPLE_PROTO */
2190 	       + 3 * nla_total_size(sizeof(u_int8_t)) /* CTA_PROTO_NUM */
2191 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_ID */
2192 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_STATUS */
2193 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_TIMEOUT */
2194 	       + nla_total_size(0) /* CTA_PROTOINFO */
2195 	       + nla_total_size(0) /* CTA_HELP */
2196 	       + nla_total_size(NF_CT_HELPER_NAME_LEN) /* CTA_HELP_NAME */
2197 	       + ctnetlink_secctx_size(ct)
2198 #ifdef CONFIG_NF_NAT_NEEDED
2199 	       + 2 * nla_total_size(0) /* CTA_NAT_SEQ_ADJ_ORIG|REPL */
2200 	       + 6 * nla_total_size(sizeof(u_int32_t)) /* CTA_NAT_SEQ_OFFSET */
2201 #endif
2202 #ifdef CONFIG_NF_CONNTRACK_MARK
2203 	       + nla_total_size(sizeof(u_int32_t)) /* CTA_MARK */
2204 #endif
2205 #ifdef CONFIG_NF_CONNTRACK_ZONES
2206 	       + nla_total_size(sizeof(u_int16_t)) /* CTA_ZONE|CTA_TUPLE_ZONE */
2207 #endif
2208 	       + ctnetlink_proto_size(ct)
2209 	       ;
2210 }
2211 
ctnetlink_glue_get_ct(const struct sk_buff * skb,enum ip_conntrack_info * ctinfo)2212 static struct nf_conn *ctnetlink_glue_get_ct(const struct sk_buff *skb,
2213 					     enum ip_conntrack_info *ctinfo)
2214 {
2215 	return nf_ct_get(skb, ctinfo);
2216 }
2217 
__ctnetlink_glue_build(struct sk_buff * skb,struct nf_conn * ct)2218 static int __ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct)
2219 {
2220 	const struct nf_conntrack_zone *zone;
2221 	struct nlattr *nest_parms;
2222 
2223 	zone = nf_ct_zone(ct);
2224 
2225 	nest_parms = nla_nest_start(skb, CTA_TUPLE_ORIG | NLA_F_NESTED);
2226 	if (!nest_parms)
2227 		goto nla_put_failure;
2228 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
2229 		goto nla_put_failure;
2230 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
2231 				   NF_CT_ZONE_DIR_ORIG) < 0)
2232 		goto nla_put_failure;
2233 	nla_nest_end(skb, nest_parms);
2234 
2235 	nest_parms = nla_nest_start(skb, CTA_TUPLE_REPLY | NLA_F_NESTED);
2236 	if (!nest_parms)
2237 		goto nla_put_failure;
2238 	if (ctnetlink_dump_tuples(skb, nf_ct_tuple(ct, IP_CT_DIR_REPLY)) < 0)
2239 		goto nla_put_failure;
2240 	if (ctnetlink_dump_zone_id(skb, CTA_TUPLE_ZONE, zone,
2241 				   NF_CT_ZONE_DIR_REPL) < 0)
2242 		goto nla_put_failure;
2243 	nla_nest_end(skb, nest_parms);
2244 
2245 	if (ctnetlink_dump_zone_id(skb, CTA_ZONE, zone,
2246 				   NF_CT_DEFAULT_ZONE_DIR) < 0)
2247 		goto nla_put_failure;
2248 
2249 	if (ctnetlink_dump_id(skb, ct) < 0)
2250 		goto nla_put_failure;
2251 
2252 	if (ctnetlink_dump_status(skb, ct) < 0)
2253 		goto nla_put_failure;
2254 
2255 	if (ctnetlink_dump_timeout(skb, ct) < 0)
2256 		goto nla_put_failure;
2257 
2258 	if (ctnetlink_dump_protoinfo(skb, ct) < 0)
2259 		goto nla_put_failure;
2260 
2261 	if (ctnetlink_dump_helpinfo(skb, ct) < 0)
2262 		goto nla_put_failure;
2263 
2264 #ifdef CONFIG_NF_CONNTRACK_SECMARK
2265 	if (ct->secmark && ctnetlink_dump_secctx(skb, ct) < 0)
2266 		goto nla_put_failure;
2267 #endif
2268 	if (ct->master && ctnetlink_dump_master(skb, ct) < 0)
2269 		goto nla_put_failure;
2270 
2271 	if ((ct->status & IPS_SEQ_ADJUST) &&
2272 	    ctnetlink_dump_ct_seq_adj(skb, ct) < 0)
2273 		goto nla_put_failure;
2274 
2275 #ifdef CONFIG_NF_CONNTRACK_MARK
2276 	if (ct->mark && ctnetlink_dump_mark(skb, ct) < 0)
2277 		goto nla_put_failure;
2278 #endif
2279 	if (ctnetlink_dump_labels(skb, ct) < 0)
2280 		goto nla_put_failure;
2281 	return 0;
2282 
2283 nla_put_failure:
2284 	return -ENOSPC;
2285 }
2286 
2287 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)2288 ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct,
2289 		     enum ip_conntrack_info ctinfo,
2290 		     u_int16_t ct_attr, u_int16_t ct_info_attr)
2291 {
2292 	struct nlattr *nest_parms;
2293 
2294 	nest_parms = nla_nest_start(skb, ct_attr | NLA_F_NESTED);
2295 	if (!nest_parms)
2296 		goto nla_put_failure;
2297 
2298 	if (__ctnetlink_glue_build(skb, ct) < 0)
2299 		goto nla_put_failure;
2300 
2301 	nla_nest_end(skb, nest_parms);
2302 
2303 	if (nla_put_be32(skb, ct_info_attr, htonl(ctinfo)))
2304 		goto nla_put_failure;
2305 
2306 	return 0;
2307 
2308 nla_put_failure:
2309 	return -ENOSPC;
2310 }
2311 
2312 static int
ctnetlink_update_status(struct nf_conn * ct,const struct nlattr * const cda[])2313 ctnetlink_update_status(struct nf_conn *ct, const struct nlattr * const cda[])
2314 {
2315 	unsigned int status = ntohl(nla_get_be32(cda[CTA_STATUS]));
2316 	unsigned long d = ct->status ^ status;
2317 
2318 	if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
2319 		/* SEEN_REPLY bit can only be set */
2320 		return -EBUSY;
2321 
2322 	if (d & IPS_ASSURED && !(status & IPS_ASSURED))
2323 		/* ASSURED bit can only be set */
2324 		return -EBUSY;
2325 
2326 	/* This check is less strict than ctnetlink_change_status()
2327 	 * because callers often flip IPS_EXPECTED bits when sending
2328 	 * an NFQA_CT attribute to the kernel.  So ignore the
2329 	 * unchangeable bits but do not error out. Also user programs
2330 	 * are allowed to clear the bits that they are allowed to change.
2331 	 */
2332 	__ctnetlink_change_status(ct, status, ~status);
2333 	return 0;
2334 }
2335 
2336 static int
ctnetlink_glue_parse_ct(const struct nlattr * cda[],struct nf_conn * ct)2337 ctnetlink_glue_parse_ct(const struct nlattr *cda[], struct nf_conn *ct)
2338 {
2339 	int err;
2340 
2341 	if (cda[CTA_TIMEOUT]) {
2342 		err = ctnetlink_change_timeout(ct, cda);
2343 		if (err < 0)
2344 			return err;
2345 	}
2346 	if (cda[CTA_STATUS]) {
2347 		err = ctnetlink_update_status(ct, cda);
2348 		if (err < 0)
2349 			return err;
2350 	}
2351 	if (cda[CTA_HELP]) {
2352 		err = ctnetlink_change_helper(ct, cda);
2353 		if (err < 0)
2354 			return err;
2355 	}
2356 	if (cda[CTA_LABELS]) {
2357 		err = ctnetlink_attach_labels(ct, cda);
2358 		if (err < 0)
2359 			return err;
2360 	}
2361 #if defined(CONFIG_NF_CONNTRACK_MARK)
2362 	if (cda[CTA_MARK]) {
2363 		u32 mask = 0, mark, newmark;
2364 		if (cda[CTA_MARK_MASK])
2365 			mask = ~ntohl(nla_get_be32(cda[CTA_MARK_MASK]));
2366 
2367 		mark = ntohl(nla_get_be32(cda[CTA_MARK]));
2368 		newmark = (ct->mark & mask) ^ mark;
2369 		if (newmark != ct->mark)
2370 			ct->mark = newmark;
2371 	}
2372 #endif
2373 	return 0;
2374 }
2375 
2376 static int
ctnetlink_glue_parse(const struct nlattr * attr,struct nf_conn * ct)2377 ctnetlink_glue_parse(const struct nlattr *attr, struct nf_conn *ct)
2378 {
2379 	struct nlattr *cda[CTA_MAX+1];
2380 	int ret;
2381 
2382 	ret = nla_parse_nested(cda, CTA_MAX, attr, ct_nla_policy, NULL);
2383 	if (ret < 0)
2384 		return ret;
2385 
2386 	return ctnetlink_glue_parse_ct((const struct nlattr **)cda, ct);
2387 }
2388 
ctnetlink_glue_exp_parse(const struct nlattr * const * cda,const struct nf_conn * ct,struct nf_conntrack_tuple * tuple,struct nf_conntrack_tuple * mask)2389 static int ctnetlink_glue_exp_parse(const struct nlattr * const *cda,
2390 				    const struct nf_conn *ct,
2391 				    struct nf_conntrack_tuple *tuple,
2392 				    struct nf_conntrack_tuple *mask)
2393 {
2394 	int err;
2395 
2396 	err = ctnetlink_parse_tuple(cda, tuple, CTA_EXPECT_TUPLE,
2397 				    nf_ct_l3num(ct), NULL);
2398 	if (err < 0)
2399 		return err;
2400 
2401 	return ctnetlink_parse_tuple(cda, mask, CTA_EXPECT_MASK,
2402 				     nf_ct_l3num(ct), NULL);
2403 }
2404 
2405 static int
ctnetlink_glue_attach_expect(const struct nlattr * attr,struct nf_conn * ct,u32 portid,u32 report)2406 ctnetlink_glue_attach_expect(const struct nlattr *attr, struct nf_conn *ct,
2407 			     u32 portid, u32 report)
2408 {
2409 	struct nlattr *cda[CTA_EXPECT_MAX+1];
2410 	struct nf_conntrack_tuple tuple, mask;
2411 	struct nf_conntrack_helper *helper = NULL;
2412 	struct nf_conntrack_expect *exp;
2413 	int err;
2414 
2415 	err = nla_parse_nested(cda, CTA_EXPECT_MAX, attr, exp_nla_policy,
2416 			       NULL);
2417 	if (err < 0)
2418 		return err;
2419 
2420 	err = ctnetlink_glue_exp_parse((const struct nlattr * const *)cda,
2421 				       ct, &tuple, &mask);
2422 	if (err < 0)
2423 		return err;
2424 
2425 	if (cda[CTA_EXPECT_HELP_NAME]) {
2426 		const char *helpname = nla_data(cda[CTA_EXPECT_HELP_NAME]);
2427 
2428 		helper = __nf_conntrack_helper_find(helpname, nf_ct_l3num(ct),
2429 						    nf_ct_protonum(ct));
2430 		if (helper == NULL)
2431 			return -EOPNOTSUPP;
2432 	}
2433 
2434 	exp = ctnetlink_alloc_expect((const struct nlattr * const *)cda, ct,
2435 				     helper, &tuple, &mask);
2436 	if (IS_ERR(exp))
2437 		return PTR_ERR(exp);
2438 
2439 	err = nf_ct_expect_related_report(exp, portid, report);
2440 	nf_ct_expect_put(exp);
2441 	return err;
2442 }
2443 
ctnetlink_glue_seqadj(struct sk_buff * skb,struct nf_conn * ct,enum ip_conntrack_info ctinfo,int diff)2444 static void ctnetlink_glue_seqadj(struct sk_buff *skb, struct nf_conn *ct,
2445 				  enum ip_conntrack_info ctinfo, int diff)
2446 {
2447 	if (!(ct->status & IPS_NAT_MASK))
2448 		return;
2449 
2450 	nf_ct_tcp_seqadj_set(skb, ct, ctinfo, diff);
2451 }
2452 
2453 static struct nfnl_ct_hook ctnetlink_glue_hook = {
2454 	.get_ct		= ctnetlink_glue_get_ct,
2455 	.build_size	= ctnetlink_glue_build_size,
2456 	.build		= ctnetlink_glue_build,
2457 	.parse		= ctnetlink_glue_parse,
2458 	.attach_expect	= ctnetlink_glue_attach_expect,
2459 	.seq_adjust	= ctnetlink_glue_seqadj,
2460 };
2461 #endif /* CONFIG_NETFILTER_NETLINK_GLUE_CT */
2462 
2463 /***********************************************************************
2464  * EXPECT
2465  ***********************************************************************/
2466 
ctnetlink_exp_dump_tuple(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,u32 type)2467 static int ctnetlink_exp_dump_tuple(struct sk_buff *skb,
2468 				    const struct nf_conntrack_tuple *tuple,
2469 				    u32 type)
2470 {
2471 	struct nlattr *nest_parms;
2472 
2473 	nest_parms = nla_nest_start(skb, type | NLA_F_NESTED);
2474 	if (!nest_parms)
2475 		goto nla_put_failure;
2476 	if (ctnetlink_dump_tuples(skb, tuple) < 0)
2477 		goto nla_put_failure;
2478 	nla_nest_end(skb, nest_parms);
2479 
2480 	return 0;
2481 
2482 nla_put_failure:
2483 	return -1;
2484 }
2485 
ctnetlink_exp_dump_mask(struct sk_buff * skb,const struct nf_conntrack_tuple * tuple,const struct nf_conntrack_tuple_mask * mask)2486 static int ctnetlink_exp_dump_mask(struct sk_buff *skb,
2487 				   const struct nf_conntrack_tuple *tuple,
2488 				   const struct nf_conntrack_tuple_mask *mask)
2489 {
2490 	const struct nf_conntrack_l3proto *l3proto;
2491 	const struct nf_conntrack_l4proto *l4proto;
2492 	struct nf_conntrack_tuple m;
2493 	struct nlattr *nest_parms;
2494 	int ret;
2495 
2496 	memset(&m, 0xFF, sizeof(m));
2497 	memcpy(&m.src.u3, &mask->src.u3, sizeof(m.src.u3));
2498 	m.src.u.all = mask->src.u.all;
2499 	m.dst.protonum = tuple->dst.protonum;
2500 
2501 	nest_parms = nla_nest_start(skb, CTA_EXPECT_MASK | NLA_F_NESTED);
2502 	if (!nest_parms)
2503 		goto nla_put_failure;
2504 
2505 	rcu_read_lock();
2506 	l3proto = __nf_ct_l3proto_find(tuple->src.l3num);
2507 	ret = ctnetlink_dump_tuples_ip(skb, &m, l3proto);
2508 	if (ret >= 0) {
2509 		l4proto = __nf_ct_l4proto_find(tuple->src.l3num,
2510 					       tuple->dst.protonum);
2511 	ret = ctnetlink_dump_tuples_proto(skb, &m, l4proto);
2512 	}
2513 	rcu_read_unlock();
2514 
2515 	if (unlikely(ret < 0))
2516 		goto nla_put_failure;
2517 
2518 	nla_nest_end(skb, nest_parms);
2519 
2520 	return 0;
2521 
2522 nla_put_failure:
2523 	return -1;
2524 }
2525 
2526 static const union nf_inet_addr any_addr;
2527 
nf_expect_get_id(const struct nf_conntrack_expect * exp)2528 static __be32 nf_expect_get_id(const struct nf_conntrack_expect *exp)
2529 {
2530 	static __read_mostly siphash_key_t exp_id_seed;
2531 	unsigned long a, b, c, d;
2532 
2533 	net_get_random_once(&exp_id_seed, sizeof(exp_id_seed));
2534 
2535 	a = (unsigned long)exp;
2536 	b = (unsigned long)exp->helper;
2537 	c = (unsigned long)exp->master;
2538 	d = (unsigned long)siphash(&exp->tuple, sizeof(exp->tuple), &exp_id_seed);
2539 
2540 #ifdef CONFIG_64BIT
2541 	return (__force __be32)siphash_4u64((u64)a, (u64)b, (u64)c, (u64)d, &exp_id_seed);
2542 #else
2543 	return (__force __be32)siphash_4u32((u32)a, (u32)b, (u32)c, (u32)d, &exp_id_seed);
2544 #endif
2545 }
2546 
2547 static int
ctnetlink_exp_dump_expect(struct sk_buff * skb,const struct nf_conntrack_expect * exp)2548 ctnetlink_exp_dump_expect(struct sk_buff *skb,
2549 			  const struct nf_conntrack_expect *exp)
2550 {
2551 	struct nf_conn *master = exp->master;
2552 	long timeout = ((long)exp->timeout.expires - (long)jiffies) / HZ;
2553 	struct nf_conn_help *help;
2554 #ifdef CONFIG_NF_NAT_NEEDED
2555 	struct nlattr *nest_parms;
2556 	struct nf_conntrack_tuple nat_tuple = {};
2557 #endif
2558 	struct nf_ct_helper_expectfn *expfn;
2559 
2560 	if (timeout < 0)
2561 		timeout = 0;
2562 
2563 	if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
2564 		goto nla_put_failure;
2565 	if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
2566 		goto nla_put_failure;
2567 	if (ctnetlink_exp_dump_tuple(skb,
2568 				 &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
2569 				 CTA_EXPECT_MASTER) < 0)
2570 		goto nla_put_failure;
2571 
2572 #ifdef CONFIG_NF_NAT_NEEDED
2573 	if (!nf_inet_addr_cmp(&exp->saved_addr, &any_addr) ||
2574 	    exp->saved_proto.all) {
2575 		nest_parms = nla_nest_start(skb, CTA_EXPECT_NAT | NLA_F_NESTED);
2576 		if (!nest_parms)
2577 			goto nla_put_failure;
2578 
2579 		if (nla_put_be32(skb, CTA_EXPECT_NAT_DIR, htonl(exp->dir)))
2580 			goto nla_put_failure;
2581 
2582 		nat_tuple.src.l3num = nf_ct_l3num(master);
2583 		nat_tuple.src.u3 = exp->saved_addr;
2584 		nat_tuple.dst.protonum = nf_ct_protonum(master);
2585 		nat_tuple.src.u = exp->saved_proto;
2586 
2587 		if (ctnetlink_exp_dump_tuple(skb, &nat_tuple,
2588 						CTA_EXPECT_NAT_TUPLE) < 0)
2589 	                goto nla_put_failure;
2590 	        nla_nest_end(skb, nest_parms);
2591 	}
2592 #endif
2593 	if (nla_put_be32(skb, CTA_EXPECT_TIMEOUT, htonl(timeout)) ||
2594 	    nla_put_be32(skb, CTA_EXPECT_ID, nf_expect_get_id(exp)) ||
2595 	    nla_put_be32(skb, CTA_EXPECT_FLAGS, htonl(exp->flags)) ||
2596 	    nla_put_be32(skb, CTA_EXPECT_CLASS, htonl(exp->class)))
2597 		goto nla_put_failure;
2598 	help = nfct_help(master);
2599 	if (help) {
2600 		struct nf_conntrack_helper *helper;
2601 
2602 		helper = rcu_dereference(help->helper);
2603 		if (helper &&
2604 		    nla_put_string(skb, CTA_EXPECT_HELP_NAME, helper->name))
2605 			goto nla_put_failure;
2606 	}
2607 	expfn = nf_ct_helper_expectfn_find_by_symbol(exp->expectfn);
2608 	if (expfn != NULL &&
2609 	    nla_put_string(skb, CTA_EXPECT_FN, expfn->name))
2610 		goto nla_put_failure;
2611 
2612 	return 0;
2613 
2614 nla_put_failure:
2615 	return -1;
2616 }
2617 
2618 static int
ctnetlink_exp_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int event,const struct nf_conntrack_expect * exp)2619 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 portid, u32 seq,
2620 			int event, const struct nf_conntrack_expect *exp)
2621 {
2622 	struct nlmsghdr *nlh;
2623 	struct nfgenmsg *nfmsg;
2624 	unsigned int flags = portid ? NLM_F_MULTI : 0;
2625 
2626 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK_EXP, event);
2627 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags);
2628 	if (nlh == NULL)
2629 		goto nlmsg_failure;
2630 
2631 	nfmsg = nlmsg_data(nlh);
2632 	nfmsg->nfgen_family = exp->tuple.src.l3num;
2633 	nfmsg->version	    = NFNETLINK_V0;
2634 	nfmsg->res_id	    = 0;
2635 
2636 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
2637 		goto nla_put_failure;
2638 
2639 	nlmsg_end(skb, nlh);
2640 	return skb->len;
2641 
2642 nlmsg_failure:
2643 nla_put_failure:
2644 	nlmsg_cancel(skb, nlh);
2645 	return -1;
2646 }
2647 
2648 #ifdef CONFIG_NF_CONNTRACK_EVENTS
2649 static int
ctnetlink_expect_event(unsigned int events,struct nf_exp_event * item)2650 ctnetlink_expect_event(unsigned int events, struct nf_exp_event *item)
2651 {
2652 	struct nf_conntrack_expect *exp = item->exp;
2653 	struct net *net = nf_ct_exp_net(exp);
2654 	struct nlmsghdr *nlh;
2655 	struct nfgenmsg *nfmsg;
2656 	struct sk_buff *skb;
2657 	unsigned int type, group;
2658 	int flags = 0;
2659 
2660 	if (events & (1 << IPEXP_DESTROY)) {
2661 		type = IPCTNL_MSG_EXP_DELETE;
2662 		group = NFNLGRP_CONNTRACK_EXP_DESTROY;
2663 	} else if (events & (1 << IPEXP_NEW)) {
2664 		type = IPCTNL_MSG_EXP_NEW;
2665 		flags = NLM_F_CREATE|NLM_F_EXCL;
2666 		group = NFNLGRP_CONNTRACK_EXP_NEW;
2667 	} else
2668 		return 0;
2669 
2670 	if (!item->report && !nfnetlink_has_listeners(net, group))
2671 		return 0;
2672 
2673 	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
2674 	if (skb == NULL)
2675 		goto errout;
2676 
2677 	type = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK_EXP, type);
2678 	nlh = nlmsg_put(skb, item->portid, 0, type, sizeof(*nfmsg), flags);
2679 	if (nlh == NULL)
2680 		goto nlmsg_failure;
2681 
2682 	nfmsg = nlmsg_data(nlh);
2683 	nfmsg->nfgen_family = exp->tuple.src.l3num;
2684 	nfmsg->version	    = NFNETLINK_V0;
2685 	nfmsg->res_id	    = 0;
2686 
2687 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
2688 		goto nla_put_failure;
2689 
2690 	nlmsg_end(skb, nlh);
2691 	nfnetlink_send(skb, net, item->portid, group, item->report, GFP_ATOMIC);
2692 	return 0;
2693 
2694 nla_put_failure:
2695 	nlmsg_cancel(skb, nlh);
2696 nlmsg_failure:
2697 	kfree_skb(skb);
2698 errout:
2699 	nfnetlink_set_err(net, 0, 0, -ENOBUFS);
2700 	return 0;
2701 }
2702 #endif
ctnetlink_exp_done(struct netlink_callback * cb)2703 static int ctnetlink_exp_done(struct netlink_callback *cb)
2704 {
2705 	if (cb->args[1])
2706 		nf_ct_expect_put((struct nf_conntrack_expect *)cb->args[1]);
2707 	return 0;
2708 }
2709 
2710 static int
ctnetlink_exp_dump_table(struct sk_buff * skb,struct netlink_callback * cb)2711 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
2712 {
2713 	struct net *net = sock_net(skb->sk);
2714 	struct nf_conntrack_expect *exp, *last;
2715 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
2716 	u_int8_t l3proto = nfmsg->nfgen_family;
2717 
2718 	rcu_read_lock();
2719 	last = (struct nf_conntrack_expect *)cb->args[1];
2720 	for (; cb->args[0] < nf_ct_expect_hsize; cb->args[0]++) {
2721 restart:
2722 		hlist_for_each_entry_rcu(exp, &nf_ct_expect_hash[cb->args[0]],
2723 					 hnode) {
2724 			if (l3proto && exp->tuple.src.l3num != l3proto)
2725 				continue;
2726 
2727 			if (!net_eq(nf_ct_net(exp->master), net))
2728 				continue;
2729 
2730 			if (cb->args[1]) {
2731 				if (exp != last)
2732 					continue;
2733 				cb->args[1] = 0;
2734 			}
2735 			if (ctnetlink_exp_fill_info(skb,
2736 						    NETLINK_CB(cb->skb).portid,
2737 						    cb->nlh->nlmsg_seq,
2738 						    IPCTNL_MSG_EXP_NEW,
2739 						    exp) < 0) {
2740 				if (!refcount_inc_not_zero(&exp->use))
2741 					continue;
2742 				cb->args[1] = (unsigned long)exp;
2743 				goto out;
2744 			}
2745 		}
2746 		if (cb->args[1]) {
2747 			cb->args[1] = 0;
2748 			goto restart;
2749 		}
2750 	}
2751 out:
2752 	rcu_read_unlock();
2753 	if (last)
2754 		nf_ct_expect_put(last);
2755 
2756 	return skb->len;
2757 }
2758 
2759 static int
ctnetlink_exp_ct_dump_table(struct sk_buff * skb,struct netlink_callback * cb)2760 ctnetlink_exp_ct_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
2761 {
2762 	struct nf_conntrack_expect *exp, *last;
2763 	struct nfgenmsg *nfmsg = nlmsg_data(cb->nlh);
2764 	struct nf_conn *ct = cb->data;
2765 	struct nf_conn_help *help = nfct_help(ct);
2766 	u_int8_t l3proto = nfmsg->nfgen_family;
2767 
2768 	if (cb->args[0])
2769 		return 0;
2770 
2771 	rcu_read_lock();
2772 	last = (struct nf_conntrack_expect *)cb->args[1];
2773 restart:
2774 	hlist_for_each_entry_rcu(exp, &help->expectations, lnode) {
2775 		if (l3proto && exp->tuple.src.l3num != l3proto)
2776 			continue;
2777 		if (cb->args[1]) {
2778 			if (exp != last)
2779 				continue;
2780 			cb->args[1] = 0;
2781 		}
2782 		if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).portid,
2783 					    cb->nlh->nlmsg_seq,
2784 					    IPCTNL_MSG_EXP_NEW,
2785 					    exp) < 0) {
2786 			if (!refcount_inc_not_zero(&exp->use))
2787 				continue;
2788 			cb->args[1] = (unsigned long)exp;
2789 			goto out;
2790 		}
2791 	}
2792 	if (cb->args[1]) {
2793 		cb->args[1] = 0;
2794 		goto restart;
2795 	}
2796 	cb->args[0] = 1;
2797 out:
2798 	rcu_read_unlock();
2799 	if (last)
2800 		nf_ct_expect_put(last);
2801 
2802 	return skb->len;
2803 }
2804 
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)2805 static int ctnetlink_dump_exp_ct(struct net *net, struct sock *ctnl,
2806 				 struct sk_buff *skb,
2807 				 const struct nlmsghdr *nlh,
2808 				 const struct nlattr * const cda[],
2809 				 struct netlink_ext_ack *extack)
2810 {
2811 	int err;
2812 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
2813 	u_int8_t u3 = nfmsg->nfgen_family;
2814 	struct nf_conntrack_tuple tuple;
2815 	struct nf_conntrack_tuple_hash *h;
2816 	struct nf_conn *ct;
2817 	struct nf_conntrack_zone zone;
2818 	struct netlink_dump_control c = {
2819 		.dump = ctnetlink_exp_ct_dump_table,
2820 		.done = ctnetlink_exp_done,
2821 	};
2822 
2823 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER,
2824 				    u3, NULL);
2825 	if (err < 0)
2826 		return err;
2827 
2828 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
2829 	if (err < 0)
2830 		return err;
2831 
2832 	h = nf_conntrack_find_get(net, &zone, &tuple);
2833 	if (!h)
2834 		return -ENOENT;
2835 
2836 	ct = nf_ct_tuplehash_to_ctrack(h);
2837 	/* No expectation linked to this connection tracking. */
2838 	if (!nfct_help(ct)) {
2839 		nf_ct_put(ct);
2840 		return 0;
2841 	}
2842 
2843 	c.data = ct;
2844 
2845 	err = netlink_dump_start(ctnl, skb, nlh, &c);
2846 	nf_ct_put(ct);
2847 
2848 	return err;
2849 }
2850 
ctnetlink_get_expect(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)2851 static int ctnetlink_get_expect(struct net *net, struct sock *ctnl,
2852 				struct sk_buff *skb, const struct nlmsghdr *nlh,
2853 				const struct nlattr * const cda[],
2854 				struct netlink_ext_ack *extack)
2855 {
2856 	struct nf_conntrack_tuple tuple;
2857 	struct nf_conntrack_expect *exp;
2858 	struct sk_buff *skb2;
2859 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
2860 	u_int8_t u3 = nfmsg->nfgen_family;
2861 	struct nf_conntrack_zone zone;
2862 	int err;
2863 
2864 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
2865 		if (cda[CTA_EXPECT_MASTER])
2866 			return ctnetlink_dump_exp_ct(net, ctnl, skb, nlh, cda,
2867 						     extack);
2868 		else {
2869 			struct netlink_dump_control c = {
2870 				.dump = ctnetlink_exp_dump_table,
2871 				.done = ctnetlink_exp_done,
2872 			};
2873 			return netlink_dump_start(ctnl, skb, nlh, &c);
2874 		}
2875 	}
2876 
2877 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
2878 	if (err < 0)
2879 		return err;
2880 
2881 	if (cda[CTA_EXPECT_TUPLE])
2882 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
2883 					    u3, NULL);
2884 	else if (cda[CTA_EXPECT_MASTER])
2885 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER,
2886 					    u3, NULL);
2887 	else
2888 		return -EINVAL;
2889 
2890 	if (err < 0)
2891 		return err;
2892 
2893 	exp = nf_ct_expect_find_get(net, &zone, &tuple);
2894 	if (!exp)
2895 		return -ENOENT;
2896 
2897 	if (cda[CTA_EXPECT_ID]) {
2898 		__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
2899 
2900 		if (id != nf_expect_get_id(exp)) {
2901 			nf_ct_expect_put(exp);
2902 			return -ENOENT;
2903 		}
2904 	}
2905 
2906 	err = -ENOMEM;
2907 	skb2 = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
2908 	if (skb2 == NULL) {
2909 		nf_ct_expect_put(exp);
2910 		goto out;
2911 	}
2912 
2913 	rcu_read_lock();
2914 	err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).portid,
2915 				      nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW, exp);
2916 	rcu_read_unlock();
2917 	nf_ct_expect_put(exp);
2918 	if (err <= 0)
2919 		goto free;
2920 
2921 	err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).portid, MSG_DONTWAIT);
2922 	if (err < 0)
2923 		goto out;
2924 
2925 	return 0;
2926 
2927 free:
2928 	kfree_skb(skb2);
2929 out:
2930 	/* this avoids a loop in nfnetlink. */
2931 	return err == -EAGAIN ? -ENOBUFS : err;
2932 }
2933 
expect_iter_name(struct nf_conntrack_expect * exp,void * data)2934 static bool expect_iter_name(struct nf_conntrack_expect *exp, void *data)
2935 {
2936 	const struct nf_conn_help *m_help;
2937 	const char *name = data;
2938 
2939 	m_help = nfct_help(exp->master);
2940 
2941 	return strcmp(m_help->helper->name, name) == 0;
2942 }
2943 
expect_iter_all(struct nf_conntrack_expect * exp,void * data)2944 static bool expect_iter_all(struct nf_conntrack_expect *exp, void *data)
2945 {
2946 	return true;
2947 }
2948 
ctnetlink_del_expect(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)2949 static int ctnetlink_del_expect(struct net *net, struct sock *ctnl,
2950 				struct sk_buff *skb, const struct nlmsghdr *nlh,
2951 				const struct nlattr * const cda[],
2952 				struct netlink_ext_ack *extack)
2953 {
2954 	struct nf_conntrack_expect *exp;
2955 	struct nf_conntrack_tuple tuple;
2956 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
2957 	u_int8_t u3 = nfmsg->nfgen_family;
2958 	struct nf_conntrack_zone zone;
2959 	int err;
2960 
2961 	if (cda[CTA_EXPECT_TUPLE]) {
2962 		/* delete a single expect by tuple */
2963 		err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
2964 		if (err < 0)
2965 			return err;
2966 
2967 		err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
2968 					    u3, NULL);
2969 		if (err < 0)
2970 			return err;
2971 
2972 		/* bump usage count to 2 */
2973 		exp = nf_ct_expect_find_get(net, &zone, &tuple);
2974 		if (!exp)
2975 			return -ENOENT;
2976 
2977 		if (cda[CTA_EXPECT_ID]) {
2978 			__be32 id = nla_get_be32(cda[CTA_EXPECT_ID]);
2979 			if (ntohl(id) != (u32)(unsigned long)exp) {
2980 				nf_ct_expect_put(exp);
2981 				return -ENOENT;
2982 			}
2983 		}
2984 
2985 		/* after list removal, usage count == 1 */
2986 		spin_lock_bh(&nf_conntrack_expect_lock);
2987 		if (del_timer(&exp->timeout)) {
2988 			nf_ct_unlink_expect_report(exp, NETLINK_CB(skb).portid,
2989 						   nlmsg_report(nlh));
2990 			nf_ct_expect_put(exp);
2991 		}
2992 		spin_unlock_bh(&nf_conntrack_expect_lock);
2993 		/* have to put what we 'get' above.
2994 		 * after this line usage count == 0 */
2995 		nf_ct_expect_put(exp);
2996 	} else if (cda[CTA_EXPECT_HELP_NAME]) {
2997 		char *name = nla_data(cda[CTA_EXPECT_HELP_NAME]);
2998 
2999 		nf_ct_expect_iterate_net(net, expect_iter_name, name,
3000 					 NETLINK_CB(skb).portid,
3001 					 nlmsg_report(nlh));
3002 	} else {
3003 		/* This basically means we have to flush everything*/
3004 		nf_ct_expect_iterate_net(net, expect_iter_all, NULL,
3005 					 NETLINK_CB(skb).portid,
3006 					 nlmsg_report(nlh));
3007 	}
3008 
3009 	return 0;
3010 }
3011 static int
ctnetlink_change_expect(struct nf_conntrack_expect * x,const struct nlattr * const cda[])3012 ctnetlink_change_expect(struct nf_conntrack_expect *x,
3013 			const struct nlattr * const cda[])
3014 {
3015 	if (cda[CTA_EXPECT_TIMEOUT]) {
3016 		if (!del_timer(&x->timeout))
3017 			return -ETIME;
3018 
3019 		x->timeout.expires = jiffies +
3020 			ntohl(nla_get_be32(cda[CTA_EXPECT_TIMEOUT])) * HZ;
3021 		add_timer(&x->timeout);
3022 	}
3023 	return 0;
3024 }
3025 
3026 static const struct nla_policy exp_nat_nla_policy[CTA_EXPECT_NAT_MAX+1] = {
3027 	[CTA_EXPECT_NAT_DIR]	= { .type = NLA_U32 },
3028 	[CTA_EXPECT_NAT_TUPLE]	= { .type = NLA_NESTED },
3029 };
3030 
3031 static int
ctnetlink_parse_expect_nat(const struct nlattr * attr,struct nf_conntrack_expect * exp,u_int8_t u3)3032 ctnetlink_parse_expect_nat(const struct nlattr *attr,
3033 			   struct nf_conntrack_expect *exp,
3034 			   u_int8_t u3)
3035 {
3036 #ifdef CONFIG_NF_NAT_NEEDED
3037 	struct nlattr *tb[CTA_EXPECT_NAT_MAX+1];
3038 	struct nf_conntrack_tuple nat_tuple = {};
3039 	int err;
3040 
3041 	err = nla_parse_nested(tb, CTA_EXPECT_NAT_MAX, attr,
3042 			       exp_nat_nla_policy, NULL);
3043 	if (err < 0)
3044 		return err;
3045 
3046 	if (!tb[CTA_EXPECT_NAT_DIR] || !tb[CTA_EXPECT_NAT_TUPLE])
3047 		return -EINVAL;
3048 
3049 	err = ctnetlink_parse_tuple((const struct nlattr * const *)tb,
3050 				    &nat_tuple, CTA_EXPECT_NAT_TUPLE,
3051 				    u3, NULL);
3052 	if (err < 0)
3053 		return err;
3054 
3055 	exp->saved_addr = nat_tuple.src.u3;
3056 	exp->saved_proto = nat_tuple.src.u;
3057 	exp->dir = ntohl(nla_get_be32(tb[CTA_EXPECT_NAT_DIR]));
3058 
3059 	return 0;
3060 #else
3061 	return -EOPNOTSUPP;
3062 #endif
3063 }
3064 
3065 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)3066 ctnetlink_alloc_expect(const struct nlattr * const cda[], struct nf_conn *ct,
3067 		       struct nf_conntrack_helper *helper,
3068 		       struct nf_conntrack_tuple *tuple,
3069 		       struct nf_conntrack_tuple *mask)
3070 {
3071 	u_int32_t class = 0;
3072 	struct nf_conntrack_expect *exp;
3073 	struct nf_conn_help *help;
3074 	int err;
3075 
3076 	help = nfct_help(ct);
3077 	if (!help)
3078 		return ERR_PTR(-EOPNOTSUPP);
3079 
3080 	if (cda[CTA_EXPECT_CLASS] && helper) {
3081 		class = ntohl(nla_get_be32(cda[CTA_EXPECT_CLASS]));
3082 		if (class > helper->expect_class_max)
3083 			return ERR_PTR(-EINVAL);
3084 	}
3085 	exp = nf_ct_expect_alloc(ct);
3086 	if (!exp)
3087 		return ERR_PTR(-ENOMEM);
3088 
3089 	if (cda[CTA_EXPECT_FLAGS]) {
3090 		exp->flags = ntohl(nla_get_be32(cda[CTA_EXPECT_FLAGS]));
3091 		exp->flags &= ~NF_CT_EXPECT_USERSPACE;
3092 	} else {
3093 		exp->flags = 0;
3094 	}
3095 	if (cda[CTA_EXPECT_FN]) {
3096 		const char *name = nla_data(cda[CTA_EXPECT_FN]);
3097 		struct nf_ct_helper_expectfn *expfn;
3098 
3099 		expfn = nf_ct_helper_expectfn_find_by_name(name);
3100 		if (expfn == NULL) {
3101 			err = -EINVAL;
3102 			goto err_out;
3103 		}
3104 		exp->expectfn = expfn->expectfn;
3105 	} else
3106 		exp->expectfn = NULL;
3107 
3108 	exp->class = class;
3109 	exp->master = ct;
3110 	exp->helper = helper;
3111 	exp->tuple = *tuple;
3112 	exp->mask.src.u3 = mask->src.u3;
3113 	exp->mask.src.u.all = mask->src.u.all;
3114 
3115 	if (cda[CTA_EXPECT_NAT]) {
3116 		err = ctnetlink_parse_expect_nat(cda[CTA_EXPECT_NAT],
3117 						 exp, nf_ct_l3num(ct));
3118 		if (err < 0)
3119 			goto err_out;
3120 	}
3121 	return exp;
3122 err_out:
3123 	nf_ct_expect_put(exp);
3124 	return ERR_PTR(err);
3125 }
3126 
3127 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)3128 ctnetlink_create_expect(struct net *net,
3129 			const struct nf_conntrack_zone *zone,
3130 			const struct nlattr * const cda[],
3131 			u_int8_t u3, u32 portid, int report)
3132 {
3133 	struct nf_conntrack_tuple tuple, mask, master_tuple;
3134 	struct nf_conntrack_tuple_hash *h = NULL;
3135 	struct nf_conntrack_helper *helper = NULL;
3136 	struct nf_conntrack_expect *exp;
3137 	struct nf_conn *ct;
3138 	int err;
3139 
3140 	/* caller guarantees that those three CTA_EXPECT_* exist */
3141 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3142 				    u3, NULL);
3143 	if (err < 0)
3144 		return err;
3145 	err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK,
3146 				    u3, NULL);
3147 	if (err < 0)
3148 		return err;
3149 	err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER,
3150 				    u3, NULL);
3151 	if (err < 0)
3152 		return err;
3153 
3154 	/* Look for master conntrack of this expectation */
3155 	h = nf_conntrack_find_get(net, zone, &master_tuple);
3156 	if (!h)
3157 		return -ENOENT;
3158 	ct = nf_ct_tuplehash_to_ctrack(h);
3159 
3160 	rcu_read_lock();
3161 	if (cda[CTA_EXPECT_HELP_NAME]) {
3162 		const char *helpname = nla_data(cda[CTA_EXPECT_HELP_NAME]);
3163 
3164 		helper = __nf_conntrack_helper_find(helpname, u3,
3165 						    nf_ct_protonum(ct));
3166 		if (helper == NULL) {
3167 			rcu_read_unlock();
3168 #ifdef CONFIG_MODULES
3169 			if (request_module("nfct-helper-%s", helpname) < 0) {
3170 				err = -EOPNOTSUPP;
3171 				goto err_ct;
3172 			}
3173 			rcu_read_lock();
3174 			helper = __nf_conntrack_helper_find(helpname, u3,
3175 							    nf_ct_protonum(ct));
3176 			if (helper) {
3177 				err = -EAGAIN;
3178 				goto err_rcu;
3179 			}
3180 			rcu_read_unlock();
3181 #endif
3182 			err = -EOPNOTSUPP;
3183 			goto err_ct;
3184 		}
3185 	}
3186 
3187 	exp = ctnetlink_alloc_expect(cda, ct, helper, &tuple, &mask);
3188 	if (IS_ERR(exp)) {
3189 		err = PTR_ERR(exp);
3190 		goto err_rcu;
3191 	}
3192 
3193 	err = nf_ct_expect_related_report(exp, portid, report);
3194 	nf_ct_expect_put(exp);
3195 err_rcu:
3196 	rcu_read_unlock();
3197 err_ct:
3198 	nf_ct_put(ct);
3199 	return err;
3200 }
3201 
ctnetlink_new_expect(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)3202 static int ctnetlink_new_expect(struct net *net, struct sock *ctnl,
3203 				struct sk_buff *skb, const struct nlmsghdr *nlh,
3204 				const struct nlattr * const cda[],
3205 				struct netlink_ext_ack *extack)
3206 {
3207 	struct nf_conntrack_tuple tuple;
3208 	struct nf_conntrack_expect *exp;
3209 	struct nfgenmsg *nfmsg = nlmsg_data(nlh);
3210 	u_int8_t u3 = nfmsg->nfgen_family;
3211 	struct nf_conntrack_zone zone;
3212 	int err;
3213 
3214 	if (!cda[CTA_EXPECT_TUPLE]
3215 	    || !cda[CTA_EXPECT_MASK]
3216 	    || !cda[CTA_EXPECT_MASTER])
3217 		return -EINVAL;
3218 
3219 	err = ctnetlink_parse_zone(cda[CTA_EXPECT_ZONE], &zone);
3220 	if (err < 0)
3221 		return err;
3222 
3223 	err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE,
3224 				    u3, NULL);
3225 	if (err < 0)
3226 		return err;
3227 
3228 	spin_lock_bh(&nf_conntrack_expect_lock);
3229 	exp = __nf_ct_expect_find(net, &zone, &tuple);
3230 	if (!exp) {
3231 		spin_unlock_bh(&nf_conntrack_expect_lock);
3232 		err = -ENOENT;
3233 		if (nlh->nlmsg_flags & NLM_F_CREATE) {
3234 			err = ctnetlink_create_expect(net, &zone, cda, u3,
3235 						      NETLINK_CB(skb).portid,
3236 						      nlmsg_report(nlh));
3237 		}
3238 		return err;
3239 	}
3240 
3241 	err = -EEXIST;
3242 	if (!(nlh->nlmsg_flags & NLM_F_EXCL))
3243 		err = ctnetlink_change_expect(exp, cda);
3244 	spin_unlock_bh(&nf_conntrack_expect_lock);
3245 
3246 	return err;
3247 }
3248 
3249 static int
ctnetlink_exp_stat_fill_info(struct sk_buff * skb,u32 portid,u32 seq,int cpu,const struct ip_conntrack_stat * st)3250 ctnetlink_exp_stat_fill_info(struct sk_buff *skb, u32 portid, u32 seq, int cpu,
3251 			     const struct ip_conntrack_stat *st)
3252 {
3253 	struct nlmsghdr *nlh;
3254 	struct nfgenmsg *nfmsg;
3255 	unsigned int flags = portid ? NLM_F_MULTI : 0, event;
3256 
3257 	event = nfnl_msg_type(NFNL_SUBSYS_CTNETLINK,
3258 			      IPCTNL_MSG_EXP_GET_STATS_CPU);
3259 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*nfmsg), flags);
3260 	if (nlh == NULL)
3261 		goto nlmsg_failure;
3262 
3263 	nfmsg = nlmsg_data(nlh);
3264 	nfmsg->nfgen_family = AF_UNSPEC;
3265 	nfmsg->version      = NFNETLINK_V0;
3266 	nfmsg->res_id	    = htons(cpu);
3267 
3268 	if (nla_put_be32(skb, CTA_STATS_EXP_NEW, htonl(st->expect_new)) ||
3269 	    nla_put_be32(skb, CTA_STATS_EXP_CREATE, htonl(st->expect_create)) ||
3270 	    nla_put_be32(skb, CTA_STATS_EXP_DELETE, htonl(st->expect_delete)))
3271 		goto nla_put_failure;
3272 
3273 	nlmsg_end(skb, nlh);
3274 	return skb->len;
3275 
3276 nla_put_failure:
3277 nlmsg_failure:
3278 	nlmsg_cancel(skb, nlh);
3279 	return -1;
3280 }
3281 
3282 static int
ctnetlink_exp_stat_cpu_dump(struct sk_buff * skb,struct netlink_callback * cb)3283 ctnetlink_exp_stat_cpu_dump(struct sk_buff *skb, struct netlink_callback *cb)
3284 {
3285 	int cpu;
3286 	struct net *net = sock_net(skb->sk);
3287 
3288 	if (cb->args[0] == nr_cpu_ids)
3289 		return 0;
3290 
3291 	for (cpu = cb->args[0]; cpu < nr_cpu_ids; cpu++) {
3292 		const struct ip_conntrack_stat *st;
3293 
3294 		if (!cpu_possible(cpu))
3295 			continue;
3296 
3297 		st = per_cpu_ptr(net->ct.stat, cpu);
3298 		if (ctnetlink_exp_stat_fill_info(skb, NETLINK_CB(cb->skb).portid,
3299 						 cb->nlh->nlmsg_seq,
3300 						 cpu, st) < 0)
3301 			break;
3302 	}
3303 	cb->args[0] = cpu;
3304 
3305 	return skb->len;
3306 }
3307 
ctnetlink_stat_exp_cpu(struct net * net,struct sock * ctnl,struct sk_buff * skb,const struct nlmsghdr * nlh,const struct nlattr * const cda[],struct netlink_ext_ack * extack)3308 static int ctnetlink_stat_exp_cpu(struct net *net, struct sock *ctnl,
3309 				  struct sk_buff *skb,
3310 				  const struct nlmsghdr *nlh,
3311 				  const struct nlattr * const cda[],
3312 				  struct netlink_ext_ack *extack)
3313 {
3314 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
3315 		struct netlink_dump_control c = {
3316 			.dump = ctnetlink_exp_stat_cpu_dump,
3317 		};
3318 		return netlink_dump_start(ctnl, skb, nlh, &c);
3319 	}
3320 
3321 	return 0;
3322 }
3323 
3324 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3325 static struct nf_ct_event_notifier ctnl_notifier = {
3326 	.fcn = ctnetlink_conntrack_event,
3327 };
3328 
3329 static struct nf_exp_event_notifier ctnl_notifier_exp = {
3330 	.fcn = ctnetlink_expect_event,
3331 };
3332 #endif
3333 
3334 static const struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
3335 	[IPCTNL_MSG_CT_NEW]		= { .call = ctnetlink_new_conntrack,
3336 					    .attr_count = CTA_MAX,
3337 					    .policy = ct_nla_policy },
3338 	[IPCTNL_MSG_CT_GET] 		= { .call = ctnetlink_get_conntrack,
3339 					    .attr_count = CTA_MAX,
3340 					    .policy = ct_nla_policy },
3341 	[IPCTNL_MSG_CT_DELETE]  	= { .call = ctnetlink_del_conntrack,
3342 					    .attr_count = CTA_MAX,
3343 					    .policy = ct_nla_policy },
3344 	[IPCTNL_MSG_CT_GET_CTRZERO] 	= { .call = ctnetlink_get_conntrack,
3345 					    .attr_count = CTA_MAX,
3346 					    .policy = ct_nla_policy },
3347 	[IPCTNL_MSG_CT_GET_STATS_CPU]	= { .call = ctnetlink_stat_ct_cpu },
3348 	[IPCTNL_MSG_CT_GET_STATS]	= { .call = ctnetlink_stat_ct },
3349 	[IPCTNL_MSG_CT_GET_DYING]	= { .call = ctnetlink_get_ct_dying },
3350 	[IPCTNL_MSG_CT_GET_UNCONFIRMED]	= { .call = ctnetlink_get_ct_unconfirmed },
3351 };
3352 
3353 static const struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
3354 	[IPCTNL_MSG_EXP_GET]		= { .call = ctnetlink_get_expect,
3355 					    .attr_count = CTA_EXPECT_MAX,
3356 					    .policy = exp_nla_policy },
3357 	[IPCTNL_MSG_EXP_NEW]		= { .call = ctnetlink_new_expect,
3358 					    .attr_count = CTA_EXPECT_MAX,
3359 					    .policy = exp_nla_policy },
3360 	[IPCTNL_MSG_EXP_DELETE]		= { .call = ctnetlink_del_expect,
3361 					    .attr_count = CTA_EXPECT_MAX,
3362 					    .policy = exp_nla_policy },
3363 	[IPCTNL_MSG_EXP_GET_STATS_CPU]	= { .call = ctnetlink_stat_exp_cpu },
3364 };
3365 
3366 static const struct nfnetlink_subsystem ctnl_subsys = {
3367 	.name				= "conntrack",
3368 	.subsys_id			= NFNL_SUBSYS_CTNETLINK,
3369 	.cb_count			= IPCTNL_MSG_MAX,
3370 	.cb				= ctnl_cb,
3371 };
3372 
3373 static const struct nfnetlink_subsystem ctnl_exp_subsys = {
3374 	.name				= "conntrack_expect",
3375 	.subsys_id			= NFNL_SUBSYS_CTNETLINK_EXP,
3376 	.cb_count			= IPCTNL_MSG_EXP_MAX,
3377 	.cb				= ctnl_exp_cb,
3378 };
3379 
3380 MODULE_ALIAS("ip_conntrack_netlink");
3381 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
3382 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
3383 
ctnetlink_net_init(struct net * net)3384 static int __net_init ctnetlink_net_init(struct net *net)
3385 {
3386 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3387 	int ret;
3388 
3389 	ret = nf_conntrack_register_notifier(net, &ctnl_notifier);
3390 	if (ret < 0) {
3391 		pr_err("ctnetlink_init: cannot register notifier.\n");
3392 		goto err_out;
3393 	}
3394 
3395 	ret = nf_ct_expect_register_notifier(net, &ctnl_notifier_exp);
3396 	if (ret < 0) {
3397 		pr_err("ctnetlink_init: cannot expect register notifier.\n");
3398 		goto err_unreg_notifier;
3399 	}
3400 #endif
3401 	return 0;
3402 
3403 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3404 err_unreg_notifier:
3405 	nf_conntrack_unregister_notifier(net, &ctnl_notifier);
3406 err_out:
3407 	return ret;
3408 #endif
3409 }
3410 
ctnetlink_net_exit(struct net * net)3411 static void ctnetlink_net_exit(struct net *net)
3412 {
3413 #ifdef CONFIG_NF_CONNTRACK_EVENTS
3414 	nf_ct_expect_unregister_notifier(net, &ctnl_notifier_exp);
3415 	nf_conntrack_unregister_notifier(net, &ctnl_notifier);
3416 #endif
3417 }
3418 
ctnetlink_net_exit_batch(struct list_head * net_exit_list)3419 static void __net_exit ctnetlink_net_exit_batch(struct list_head *net_exit_list)
3420 {
3421 	struct net *net;
3422 
3423 	list_for_each_entry(net, net_exit_list, exit_list)
3424 		ctnetlink_net_exit(net);
3425 
3426 	/* wait for other cpus until they are done with ctnl_notifiers */
3427 	synchronize_rcu();
3428 }
3429 
3430 static struct pernet_operations ctnetlink_net_ops = {
3431 	.init		= ctnetlink_net_init,
3432 	.exit_batch	= ctnetlink_net_exit_batch,
3433 };
3434 
ctnetlink_init(void)3435 static int __init ctnetlink_init(void)
3436 {
3437 	int ret;
3438 
3439 	pr_info("ctnetlink v%s: registering with nfnetlink.\n", version);
3440 	ret = nfnetlink_subsys_register(&ctnl_subsys);
3441 	if (ret < 0) {
3442 		pr_err("ctnetlink_init: cannot register with nfnetlink.\n");
3443 		goto err_out;
3444 	}
3445 
3446 	ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
3447 	if (ret < 0) {
3448 		pr_err("ctnetlink_init: cannot register exp with nfnetlink.\n");
3449 		goto err_unreg_subsys;
3450 	}
3451 
3452 	ret = register_pernet_subsys(&ctnetlink_net_ops);
3453 	if (ret < 0) {
3454 		pr_err("ctnetlink_init: cannot register pernet operations\n");
3455 		goto err_unreg_exp_subsys;
3456 	}
3457 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
3458 	/* setup interaction between nf_queue and nf_conntrack_netlink. */
3459 	RCU_INIT_POINTER(nfnl_ct_hook, &ctnetlink_glue_hook);
3460 #endif
3461 	return 0;
3462 
3463 err_unreg_exp_subsys:
3464 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
3465 err_unreg_subsys:
3466 	nfnetlink_subsys_unregister(&ctnl_subsys);
3467 err_out:
3468 	return ret;
3469 }
3470 
ctnetlink_exit(void)3471 static void __exit ctnetlink_exit(void)
3472 {
3473 	pr_info("ctnetlink: unregistering from nfnetlink.\n");
3474 
3475 	unregister_pernet_subsys(&ctnetlink_net_ops);
3476 	nfnetlink_subsys_unregister(&ctnl_exp_subsys);
3477 	nfnetlink_subsys_unregister(&ctnl_subsys);
3478 #ifdef CONFIG_NETFILTER_NETLINK_GLUE_CT
3479 	RCU_INIT_POINTER(nfnl_ct_hook, NULL);
3480 #endif
3481 	synchronize_rcu();
3482 }
3483 
3484 module_init(ctnetlink_init);
3485 module_exit(ctnetlink_exit);
3486