[NETFILTER]: nf_conntrack: fix helper module unload races
[safe/jmp/linux-2.6] / net / netfilter / nf_conntrack_netlink.c
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) 2005-2006 by Pablo Neira Ayuso <pablo@eurodev.net>
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/types.h>
22 #include <linux/timer.h>
23 #include <linux/skbuff.h>
24 #include <linux/errno.h>
25 #include <linux/netlink.h>
26 #include <linux/spinlock.h>
27 #include <linux/interrupt.h>
28 #include <linux/notifier.h>
29
30 #include <linux/netfilter.h>
31 #include <net/netlink.h>
32 #include <net/netfilter/nf_conntrack.h>
33 #include <net/netfilter/nf_conntrack_core.h>
34 #include <net/netfilter/nf_conntrack_expect.h>
35 #include <net/netfilter/nf_conntrack_helper.h>
36 #include <net/netfilter/nf_conntrack_l3proto.h>
37 #include <net/netfilter/nf_conntrack_l4proto.h>
38 #include <net/netfilter/nf_conntrack_tuple.h>
39 #ifdef CONFIG_NF_NAT_NEEDED
40 #include <net/netfilter/nf_nat_core.h>
41 #include <net/netfilter/nf_nat_protocol.h>
42 #endif
43
44 #include <linux/netfilter/nfnetlink.h>
45 #include <linux/netfilter/nfnetlink_conntrack.h>
46
47 MODULE_LICENSE("GPL");
48
49 static char __initdata version[] = "0.93";
50
51 static inline int
52 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
53                             const struct nf_conntrack_tuple *tuple,
54                             struct nf_conntrack_l4proto *l4proto)
55 {
56         int ret = 0;
57         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
58
59         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
60
61         if (likely(l4proto->tuple_to_nfattr))
62                 ret = l4proto->tuple_to_nfattr(skb, tuple);
63
64         NFA_NEST_END(skb, nest_parms);
65
66         return ret;
67
68 nfattr_failure:
69         return -1;
70 }
71
72 static inline int
73 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
74                          const struct nf_conntrack_tuple *tuple,
75                          struct nf_conntrack_l3proto *l3proto)
76 {
77         int ret = 0;
78         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
79
80         if (likely(l3proto->tuple_to_nfattr))
81                 ret = l3proto->tuple_to_nfattr(skb, tuple);
82
83         NFA_NEST_END(skb, nest_parms);
84
85         return ret;
86
87 nfattr_failure:
88         return -1;
89 }
90
91 static inline int
92 ctnetlink_dump_tuples(struct sk_buff *skb,
93                       const struct nf_conntrack_tuple *tuple)
94 {
95         int ret;
96         struct nf_conntrack_l3proto *l3proto;
97         struct nf_conntrack_l4proto *l4proto;
98
99         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
100         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
101         nf_ct_l3proto_put(l3proto);
102
103         if (unlikely(ret < 0))
104                 return ret;
105
106         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
107         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
108         nf_ct_l4proto_put(l4proto);
109
110         return ret;
111 }
112
113 static inline int
114 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
115 {
116         __be32 status = htonl((u_int32_t) ct->status);
117         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
118         return 0;
119
120 nfattr_failure:
121         return -1;
122 }
123
124 static inline int
125 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
126 {
127         long timeout_l = ct->timeout.expires - jiffies;
128         __be32 timeout;
129
130         if (timeout_l < 0)
131                 timeout = 0;
132         else
133                 timeout = htonl(timeout_l / HZ);
134
135         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
136         return 0;
137
138 nfattr_failure:
139         return -1;
140 }
141
142 static inline int
143 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
144 {
145         struct nf_conntrack_l4proto *l4proto = nf_ct_l4proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num, ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
146         struct nfattr *nest_proto;
147         int ret;
148
149         if (!l4proto->to_nfattr) {
150                 nf_ct_l4proto_put(l4proto);
151                 return 0;
152         }
153
154         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
155
156         ret = l4proto->to_nfattr(skb, nest_proto, ct);
157
158         nf_ct_l4proto_put(l4proto);
159
160         NFA_NEST_END(skb, nest_proto);
161
162         return ret;
163
164 nfattr_failure:
165         nf_ct_l4proto_put(l4proto);
166         return -1;
167 }
168
169 static inline int
170 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
171 {
172         struct nfattr *nest_helper;
173         const struct nf_conn_help *help = nfct_help(ct);
174         struct nf_conntrack_helper *helper;
175
176         if (!help)
177                 return 0;
178
179         rcu_read_lock();
180         helper = rcu_dereference(help->helper);
181         if (!helper)
182                 goto out;
183
184         nest_helper = NFA_NEST(skb, CTA_HELP);
185         NFA_PUT(skb, CTA_HELP_NAME, strlen(helper->name), helper->name);
186
187         if (helper->to_nfattr)
188                 helper->to_nfattr(skb, ct);
189
190         NFA_NEST_END(skb, nest_helper);
191 out:
192         rcu_read_unlock();
193         return 0;
194
195 nfattr_failure:
196         rcu_read_unlock();
197         return -1;
198 }
199
200 #ifdef CONFIG_NF_CT_ACCT
201 static inline int
202 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
203                         enum ip_conntrack_dir dir)
204 {
205         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
206         struct nfattr *nest_count = NFA_NEST(skb, type);
207         __be32 tmp;
208
209         tmp = htonl(ct->counters[dir].packets);
210         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
211
212         tmp = htonl(ct->counters[dir].bytes);
213         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
214
215         NFA_NEST_END(skb, nest_count);
216
217         return 0;
218
219 nfattr_failure:
220         return -1;
221 }
222 #else
223 #define ctnetlink_dump_counters(a, b, c) (0)
224 #endif
225
226 #ifdef CONFIG_NF_CONNTRACK_MARK
227 static inline int
228 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
229 {
230         __be32 mark = htonl(ct->mark);
231
232         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
233         return 0;
234
235 nfattr_failure:
236         return -1;
237 }
238 #else
239 #define ctnetlink_dump_mark(a, b) (0)
240 #endif
241
242 static inline int
243 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
244 {
245         __be32 id = htonl(ct->id);
246         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
247         return 0;
248
249 nfattr_failure:
250         return -1;
251 }
252
253 static inline int
254 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
255 {
256         __be32 use = htonl(atomic_read(&ct->ct_general.use));
257
258         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
259         return 0;
260
261 nfattr_failure:
262         return -1;
263 }
264
265 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
266
267 static int
268 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
269                     int event, int nowait,
270                     const struct nf_conn *ct)
271 {
272         struct nlmsghdr *nlh;
273         struct nfgenmsg *nfmsg;
274         struct nfattr *nest_parms;
275         unsigned char *b = skb_tail_pointer(skb);
276
277         event |= NFNL_SUBSYS_CTNETLINK << 8;
278         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
279         nfmsg  = NLMSG_DATA(nlh);
280
281         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
282         nfmsg->nfgen_family =
283                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
284         nfmsg->version      = NFNETLINK_V0;
285         nfmsg->res_id       = 0;
286
287         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
288         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
289                 goto nfattr_failure;
290         NFA_NEST_END(skb, nest_parms);
291
292         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
293         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
294                 goto nfattr_failure;
295         NFA_NEST_END(skb, nest_parms);
296
297         if (ctnetlink_dump_status(skb, ct) < 0 ||
298             ctnetlink_dump_timeout(skb, ct) < 0 ||
299             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
300             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
301             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
302             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
303             ctnetlink_dump_mark(skb, ct) < 0 ||
304             ctnetlink_dump_id(skb, ct) < 0 ||
305             ctnetlink_dump_use(skb, ct) < 0)
306                 goto nfattr_failure;
307
308         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
309         return skb->len;
310
311 nlmsg_failure:
312 nfattr_failure:
313         nlmsg_trim(skb, b);
314         return -1;
315 }
316
317 #ifdef CONFIG_NF_CONNTRACK_EVENTS
318 static int ctnetlink_conntrack_event(struct notifier_block *this,
319                                      unsigned long events, void *ptr)
320 {
321         struct nlmsghdr *nlh;
322         struct nfgenmsg *nfmsg;
323         struct nfattr *nest_parms;
324         struct nf_conn *ct = (struct nf_conn *)ptr;
325         struct sk_buff *skb;
326         unsigned int type;
327         sk_buff_data_t b;
328         unsigned int flags = 0, group;
329
330         /* ignore our fake conntrack entry */
331         if (ct == &nf_conntrack_untracked)
332                 return NOTIFY_DONE;
333
334         if (events & IPCT_DESTROY) {
335                 type = IPCTNL_MSG_CT_DELETE;
336                 group = NFNLGRP_CONNTRACK_DESTROY;
337         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
338                 type = IPCTNL_MSG_CT_NEW;
339                 flags = NLM_F_CREATE|NLM_F_EXCL;
340                 group = NFNLGRP_CONNTRACK_NEW;
341         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
342                 type = IPCTNL_MSG_CT_NEW;
343                 group = NFNLGRP_CONNTRACK_UPDATE;
344         } else
345                 return NOTIFY_DONE;
346
347         if (!nfnetlink_has_listeners(group))
348                 return NOTIFY_DONE;
349
350         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
351         if (!skb)
352                 return NOTIFY_DONE;
353
354         b = skb->tail;
355
356         type |= NFNL_SUBSYS_CTNETLINK << 8;
357         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
358         nfmsg = NLMSG_DATA(nlh);
359
360         nlh->nlmsg_flags    = flags;
361         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
362         nfmsg->version  = NFNETLINK_V0;
363         nfmsg->res_id   = 0;
364
365         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
366         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
367                 goto nfattr_failure;
368         NFA_NEST_END(skb, nest_parms);
369
370         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
371         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
372                 goto nfattr_failure;
373         NFA_NEST_END(skb, nest_parms);
374
375         if (events & IPCT_DESTROY) {
376                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
377                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
378                         goto nfattr_failure;
379         } else {
380                 if (ctnetlink_dump_status(skb, ct) < 0)
381                         goto nfattr_failure;
382
383                 if (ctnetlink_dump_timeout(skb, ct) < 0)
384                         goto nfattr_failure;
385
386                 if (events & IPCT_PROTOINFO
387                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
388                         goto nfattr_failure;
389
390                 if ((events & IPCT_HELPER || nfct_help(ct))
391                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
392                         goto nfattr_failure;
393
394 #ifdef CONFIG_NF_CONNTRACK_MARK
395                 if ((events & IPCT_MARK || ct->mark)
396                     && ctnetlink_dump_mark(skb, ct) < 0)
397                         goto nfattr_failure;
398 #endif
399
400                 if (events & IPCT_COUNTER_FILLING &&
401                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
402                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
403                         goto nfattr_failure;
404         }
405
406         nlh->nlmsg_len = skb->tail - b;
407         nfnetlink_send(skb, 0, group, 0);
408         return NOTIFY_DONE;
409
410 nlmsg_failure:
411 nfattr_failure:
412         kfree_skb(skb);
413         return NOTIFY_DONE;
414 }
415 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
416
417 static int ctnetlink_done(struct netlink_callback *cb)
418 {
419         if (cb->args[1])
420                 nf_ct_put((struct nf_conn *)cb->args[1]);
421         return 0;
422 }
423
424 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
425
426 static int
427 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
428 {
429         struct nf_conn *ct, *last;
430         struct nf_conntrack_tuple_hash *h;
431         struct list_head *i;
432         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
433         u_int8_t l3proto = nfmsg->nfgen_family;
434
435         read_lock_bh(&nf_conntrack_lock);
436         last = (struct nf_conn *)cb->args[1];
437         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
438 restart:
439                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
440                         h = (struct nf_conntrack_tuple_hash *) i;
441                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
442                                 continue;
443                         ct = nf_ct_tuplehash_to_ctrack(h);
444                         /* Dump entries of a given L3 protocol number.
445                          * If it is not specified, ie. l3proto == 0,
446                          * then dump everything. */
447                         if (l3proto && L3PROTO(ct) != l3proto)
448                                 continue;
449                         if (cb->args[1]) {
450                                 if (ct != last)
451                                         continue;
452                                 cb->args[1] = 0;
453                         }
454                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
455                                                 cb->nlh->nlmsg_seq,
456                                                 IPCTNL_MSG_CT_NEW,
457                                                 1, ct) < 0) {
458                                 nf_conntrack_get(&ct->ct_general);
459                                 cb->args[1] = (unsigned long)ct;
460                                 goto out;
461                         }
462 #ifdef CONFIG_NF_CT_ACCT
463                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
464                                                 IPCTNL_MSG_CT_GET_CTRZERO)
465                                 memset(&ct->counters, 0, sizeof(ct->counters));
466 #endif
467                 }
468                 if (cb->args[1]) {
469                         cb->args[1] = 0;
470                         goto restart;
471                 }
472         }
473 out:
474         read_unlock_bh(&nf_conntrack_lock);
475         if (last)
476                 nf_ct_put(last);
477
478         return skb->len;
479 }
480
481 static inline int
482 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
483 {
484         struct nfattr *tb[CTA_IP_MAX];
485         struct nf_conntrack_l3proto *l3proto;
486         int ret = 0;
487
488         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
489
490         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
491
492         if (likely(l3proto->nfattr_to_tuple))
493                 ret = l3proto->nfattr_to_tuple(tb, tuple);
494
495         nf_ct_l3proto_put(l3proto);
496
497         return ret;
498 }
499
500 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
501         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
502 };
503
504 static inline int
505 ctnetlink_parse_tuple_proto(struct nfattr *attr,
506                             struct nf_conntrack_tuple *tuple)
507 {
508         struct nfattr *tb[CTA_PROTO_MAX];
509         struct nf_conntrack_l4proto *l4proto;
510         int ret = 0;
511
512         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
513
514         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
515                 return -EINVAL;
516
517         if (!tb[CTA_PROTO_NUM-1])
518                 return -EINVAL;
519         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
520
521         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
522
523         if (likely(l4proto->nfattr_to_tuple))
524                 ret = l4proto->nfattr_to_tuple(tb, tuple);
525
526         nf_ct_l4proto_put(l4proto);
527
528         return ret;
529 }
530
531 static inline int
532 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
533                       enum ctattr_tuple type, u_int8_t l3num)
534 {
535         struct nfattr *tb[CTA_TUPLE_MAX];
536         int err;
537
538         memset(tuple, 0, sizeof(*tuple));
539
540         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
541
542         if (!tb[CTA_TUPLE_IP-1])
543                 return -EINVAL;
544
545         tuple->src.l3num = l3num;
546
547         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
548         if (err < 0)
549                 return err;
550
551         if (!tb[CTA_TUPLE_PROTO-1])
552                 return -EINVAL;
553
554         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
555         if (err < 0)
556                 return err;
557
558         /* orig and expect tuples get DIR_ORIGINAL */
559         if (type == CTA_TUPLE_REPLY)
560                 tuple->dst.dir = IP_CT_DIR_REPLY;
561         else
562                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
563
564         return 0;
565 }
566
567 #ifdef CONFIG_NF_NAT_NEEDED
568 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
569         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
570         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
571 };
572
573 static int nfnetlink_parse_nat_proto(struct nfattr *attr,
574                                      const struct nf_conn *ct,
575                                      struct nf_nat_range *range)
576 {
577         struct nfattr *tb[CTA_PROTONAT_MAX];
578         struct nf_nat_protocol *npt;
579
580         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
581
582         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
583                 return -EINVAL;
584
585         npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
586
587         if (!npt->nfattr_to_range) {
588                 nf_nat_proto_put(npt);
589                 return 0;
590         }
591
592         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
593         if (npt->nfattr_to_range(tb, range) > 0)
594                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
595
596         nf_nat_proto_put(npt);
597
598         return 0;
599 }
600
601 static const size_t cta_min_nat[CTA_NAT_MAX] = {
602         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
603         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
604 };
605
606 static inline int
607 nfnetlink_parse_nat(struct nfattr *nat,
608                     const struct nf_conn *ct, struct nf_nat_range *range)
609 {
610         struct nfattr *tb[CTA_NAT_MAX];
611         int err;
612
613         memset(range, 0, sizeof(*range));
614
615         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
616
617         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
618                 return -EINVAL;
619
620         if (tb[CTA_NAT_MINIP-1])
621                 range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
622
623         if (!tb[CTA_NAT_MAXIP-1])
624                 range->max_ip = range->min_ip;
625         else
626                 range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
627
628         if (range->min_ip)
629                 range->flags |= IP_NAT_RANGE_MAP_IPS;
630
631         if (!tb[CTA_NAT_PROTO-1])
632                 return 0;
633
634         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
635         if (err < 0)
636                 return err;
637
638         return 0;
639 }
640 #endif
641
642 static inline int
643 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
644 {
645         struct nfattr *tb[CTA_HELP_MAX];
646
647         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
648
649         if (!tb[CTA_HELP_NAME-1])
650                 return -EINVAL;
651
652         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
653
654         return 0;
655 }
656
657 static const size_t cta_min[CTA_MAX] = {
658         [CTA_STATUS-1]          = sizeof(u_int32_t),
659         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
660         [CTA_MARK-1]            = sizeof(u_int32_t),
661         [CTA_USE-1]             = sizeof(u_int32_t),
662         [CTA_ID-1]              = sizeof(u_int32_t)
663 };
664
665 static int
666 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
667                         struct nlmsghdr *nlh, struct nfattr *cda[])
668 {
669         struct nf_conntrack_tuple_hash *h;
670         struct nf_conntrack_tuple tuple;
671         struct nf_conn *ct;
672         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
673         u_int8_t u3 = nfmsg->nfgen_family;
674         int err = 0;
675
676         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
677                 return -EINVAL;
678
679         if (cda[CTA_TUPLE_ORIG-1])
680                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
681         else if (cda[CTA_TUPLE_REPLY-1])
682                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
683         else {
684                 /* Flush the whole table */
685                 nf_conntrack_flush();
686                 return 0;
687         }
688
689         if (err < 0)
690                 return err;
691
692         h = nf_conntrack_find_get(&tuple, NULL);
693         if (!h)
694                 return -ENOENT;
695
696         ct = nf_ct_tuplehash_to_ctrack(h);
697
698         if (cda[CTA_ID-1]) {
699                 u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));
700                 if (ct->id != id) {
701                         nf_ct_put(ct);
702                         return -ENOENT;
703                 }
704         }
705         if (del_timer(&ct->timeout))
706                 ct->timeout.function((unsigned long)ct);
707
708         nf_ct_put(ct);
709
710         return 0;
711 }
712
713 static int
714 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
715                         struct nlmsghdr *nlh, struct nfattr *cda[])
716 {
717         struct nf_conntrack_tuple_hash *h;
718         struct nf_conntrack_tuple tuple;
719         struct nf_conn *ct;
720         struct sk_buff *skb2 = NULL;
721         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
722         u_int8_t u3 = nfmsg->nfgen_family;
723         int err = 0;
724
725         if (nlh->nlmsg_flags & NLM_F_DUMP) {
726 #ifndef CONFIG_NF_CT_ACCT
727                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
728                         return -ENOTSUPP;
729 #endif
730                 return netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
731                                           ctnetlink_done);
732         }
733
734         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
735                 return -EINVAL;
736
737         if (cda[CTA_TUPLE_ORIG-1])
738                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
739         else if (cda[CTA_TUPLE_REPLY-1])
740                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
741         else
742                 return -EINVAL;
743
744         if (err < 0)
745                 return err;
746
747         h = nf_conntrack_find_get(&tuple, NULL);
748         if (!h)
749                 return -ENOENT;
750
751         ct = nf_ct_tuplehash_to_ctrack(h);
752
753         err = -ENOMEM;
754         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
755         if (!skb2) {
756                 nf_ct_put(ct);
757                 return -ENOMEM;
758         }
759
760         err = ctnetlink_fill_info(skb2, NETLINK_CB(skb).pid, nlh->nlmsg_seq,
761                                   IPCTNL_MSG_CT_NEW, 1, ct);
762         nf_ct_put(ct);
763         if (err <= 0)
764                 goto free;
765
766         err = netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
767         if (err < 0)
768                 goto out;
769
770         return 0;
771
772 free:
773         kfree_skb(skb2);
774 out:
775         return err;
776 }
777
778 static inline int
779 ctnetlink_change_status(struct nf_conn *ct, struct nfattr *cda[])
780 {
781         unsigned long d;
782         unsigned int status = ntohl(*(__be32 *)NFA_DATA(cda[CTA_STATUS-1]));
783         d = ct->status ^ status;
784
785         if (d & (IPS_EXPECTED|IPS_CONFIRMED|IPS_DYING))
786                 /* unchangeable */
787                 return -EINVAL;
788
789         if (d & IPS_SEEN_REPLY && !(status & IPS_SEEN_REPLY))
790                 /* SEEN_REPLY bit can only be set */
791                 return -EINVAL;
792
793
794         if (d & IPS_ASSURED && !(status & IPS_ASSURED))
795                 /* ASSURED bit can only be set */
796                 return -EINVAL;
797
798         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
799 #ifndef CONFIG_NF_NAT_NEEDED
800                 return -EINVAL;
801 #else
802                 struct nf_nat_range range;
803
804                 if (cda[CTA_NAT_DST-1]) {
805                         if (nfnetlink_parse_nat(cda[CTA_NAT_DST-1], ct,
806                                                 &range) < 0)
807                                 return -EINVAL;
808                         if (nf_nat_initialized(ct,
809                                                HOOK2MANIP(NF_IP_PRE_ROUTING)))
810                                 return -EEXIST;
811                         nf_nat_setup_info(ct, &range, NF_IP_PRE_ROUTING);
812                 }
813                 if (cda[CTA_NAT_SRC-1]) {
814                         if (nfnetlink_parse_nat(cda[CTA_NAT_SRC-1], ct,
815                                                 &range) < 0)
816                                 return -EINVAL;
817                         if (nf_nat_initialized(ct,
818                                                HOOK2MANIP(NF_IP_POST_ROUTING)))
819                                 return -EEXIST;
820                         nf_nat_setup_info(ct, &range, NF_IP_POST_ROUTING);
821                 }
822 #endif
823         }
824
825         /* Be careful here, modifying NAT bits can screw up things,
826          * so don't let users modify them directly if they don't pass
827          * nf_nat_range. */
828         ct->status |= status & ~(IPS_NAT_DONE_MASK | IPS_NAT_MASK);
829         return 0;
830 }
831
832
833 static inline int
834 ctnetlink_change_helper(struct nf_conn *ct, struct nfattr *cda[])
835 {
836         struct nf_conntrack_helper *helper;
837         struct nf_conn_help *help = nfct_help(ct);
838         char *helpname;
839         int err;
840
841         /* don't change helper of sibling connections */
842         if (ct->master)
843                 return -EINVAL;
844
845         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
846         if (err < 0)
847                 return err;
848
849         if (!strcmp(helpname, "")) {
850                 if (help && help->helper) {
851                         /* we had a helper before ... */
852                         nf_ct_remove_expectations(ct);
853                         rcu_assign_pointer(help->helper, NULL);
854                 }
855
856                 return 0;
857         }
858
859         if (!help) {
860                 /* FIXME: we need to reallocate and rehash */
861                 return -EBUSY;
862         }
863
864         helper = __nf_conntrack_helper_find_byname(helpname);
865         if (helper == NULL)
866                 return -EINVAL;
867
868         if (help->helper == helper)
869                 return 0;
870
871         if (help->helper)
872                 /* we had a helper before ... */
873                 nf_ct_remove_expectations(ct);
874
875         /* need to zero data of old helper */
876         memset(&help->help, 0, sizeof(help->help));
877         rcu_assign_pointer(help->helper, helper);
878
879         return 0;
880 }
881
882 static inline int
883 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
884 {
885         u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
886
887         if (!del_timer(&ct->timeout))
888                 return -ETIME;
889
890         ct->timeout.expires = jiffies + timeout * HZ;
891         add_timer(&ct->timeout);
892
893         return 0;
894 }
895
896 static inline int
897 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
898 {
899         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
900         struct nf_conntrack_l4proto *l4proto;
901         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
902         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
903         int err = 0;
904
905         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
906
907         l4proto = nf_ct_l4proto_find_get(l3num, npt);
908
909         if (l4proto->from_nfattr)
910                 err = l4proto->from_nfattr(tb, ct);
911         nf_ct_l4proto_put(l4proto);
912
913         return err;
914 }
915
916 static int
917 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
918 {
919         int err;
920
921         if (cda[CTA_HELP-1]) {
922                 err = ctnetlink_change_helper(ct, cda);
923                 if (err < 0)
924                         return err;
925         }
926
927         if (cda[CTA_TIMEOUT-1]) {
928                 err = ctnetlink_change_timeout(ct, cda);
929                 if (err < 0)
930                         return err;
931         }
932
933         if (cda[CTA_STATUS-1]) {
934                 err = ctnetlink_change_status(ct, cda);
935                 if (err < 0)
936                         return err;
937         }
938
939         if (cda[CTA_PROTOINFO-1]) {
940                 err = ctnetlink_change_protoinfo(ct, cda);
941                 if (err < 0)
942                         return err;
943         }
944
945 #if defined(CONFIG_NF_CONNTRACK_MARK)
946         if (cda[CTA_MARK-1])
947                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
948 #endif
949
950         return 0;
951 }
952
953 static int
954 ctnetlink_create_conntrack(struct nfattr *cda[],
955                            struct nf_conntrack_tuple *otuple,
956                            struct nf_conntrack_tuple *rtuple)
957 {
958         struct nf_conn *ct;
959         int err = -EINVAL;
960         struct nf_conn_help *help;
961         struct nf_conntrack_helper *helper = NULL;
962
963         ct = nf_conntrack_alloc(otuple, rtuple);
964         if (ct == NULL || IS_ERR(ct))
965                 return -ENOMEM;
966
967         if (!cda[CTA_TIMEOUT-1])
968                 goto err;
969         ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
970
971         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
972         ct->status |= IPS_CONFIRMED;
973
974         if (cda[CTA_STATUS-1]) {
975                 err = ctnetlink_change_status(ct, cda);
976                 if (err < 0)
977                         goto err;
978         }
979
980         if (cda[CTA_PROTOINFO-1]) {
981                 err = ctnetlink_change_protoinfo(ct, cda);
982                 if (err < 0)
983                         goto err;
984         }
985
986 #if defined(CONFIG_NF_CONNTRACK_MARK)
987         if (cda[CTA_MARK-1])
988                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
989 #endif
990
991         help = nfct_help(ct);
992         if (help) {
993                 helper = nf_ct_helper_find_get(rtuple);
994                 /* not in hash table yet so not strictly necessary */
995                 rcu_assign_pointer(help->helper, helper);
996         }
997
998         add_timer(&ct->timeout);
999         nf_conntrack_hash_insert(ct);
1000
1001         if (helper)
1002                 nf_ct_helper_put(helper);
1003
1004         return 0;
1005
1006 err:
1007         nf_conntrack_free(ct);
1008         return err;
1009 }
1010
1011 static int
1012 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1013                         struct nlmsghdr *nlh, struct nfattr *cda[])
1014 {
1015         struct nf_conntrack_tuple otuple, rtuple;
1016         struct nf_conntrack_tuple_hash *h = NULL;
1017         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1018         u_int8_t u3 = nfmsg->nfgen_family;
1019         int err = 0;
1020
1021         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1022                 return -EINVAL;
1023
1024         if (cda[CTA_TUPLE_ORIG-1]) {
1025                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1026                 if (err < 0)
1027                         return err;
1028         }
1029
1030         if (cda[CTA_TUPLE_REPLY-1]) {
1031                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1032                 if (err < 0)
1033                         return err;
1034         }
1035
1036         write_lock_bh(&nf_conntrack_lock);
1037         if (cda[CTA_TUPLE_ORIG-1])
1038                 h = __nf_conntrack_find(&otuple, NULL);
1039         else if (cda[CTA_TUPLE_REPLY-1])
1040                 h = __nf_conntrack_find(&rtuple, NULL);
1041
1042         if (h == NULL) {
1043                 write_unlock_bh(&nf_conntrack_lock);
1044                 err = -ENOENT;
1045                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1046                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1047                 return err;
1048         }
1049         /* implicit 'else' */
1050
1051         /* we only allow nat config for new conntracks */
1052         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1053                 err = -EINVAL;
1054                 goto out_unlock;
1055         }
1056
1057         /* We manipulate the conntrack inside the global conntrack table lock,
1058          * so there's no need to increase the refcount */
1059         err = -EEXIST;
1060         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1061                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1062
1063 out_unlock:
1064         write_unlock_bh(&nf_conntrack_lock);
1065         return err;
1066 }
1067
1068 /***********************************************************************
1069  * EXPECT
1070  ***********************************************************************/
1071
1072 static inline int
1073 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1074                          const struct nf_conntrack_tuple *tuple,
1075                          enum ctattr_expect type)
1076 {
1077         struct nfattr *nest_parms = NFA_NEST(skb, type);
1078
1079         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1080                 goto nfattr_failure;
1081
1082         NFA_NEST_END(skb, nest_parms);
1083
1084         return 0;
1085
1086 nfattr_failure:
1087         return -1;
1088 }
1089
1090 static inline int
1091 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1092                         const struct nf_conntrack_tuple *tuple,
1093                         const struct nf_conntrack_tuple *mask)
1094 {
1095         int ret;
1096         struct nf_conntrack_l3proto *l3proto;
1097         struct nf_conntrack_l4proto *l4proto;
1098         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1099
1100         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1101         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1102         nf_ct_l3proto_put(l3proto);
1103
1104         if (unlikely(ret < 0))
1105                 goto nfattr_failure;
1106
1107         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1108         ret = ctnetlink_dump_tuples_proto(skb, mask, l4proto);
1109         nf_ct_l4proto_put(l4proto);
1110         if (unlikely(ret < 0))
1111                 goto nfattr_failure;
1112
1113         NFA_NEST_END(skb, nest_parms);
1114
1115         return 0;
1116
1117 nfattr_failure:
1118         return -1;
1119 }
1120
1121 static inline int
1122 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1123                           const struct nf_conntrack_expect *exp)
1124 {
1125         struct nf_conn *master = exp->master;
1126         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1127         __be32 id = htonl(exp->id);
1128
1129         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1130                 goto nfattr_failure;
1131         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1132                 goto nfattr_failure;
1133         if (ctnetlink_exp_dump_tuple(skb,
1134                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1135                                  CTA_EXPECT_MASTER) < 0)
1136                 goto nfattr_failure;
1137
1138         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1139         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1140
1141         return 0;
1142
1143 nfattr_failure:
1144         return -1;
1145 }
1146
1147 static int
1148 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1149                     int event,
1150                     int nowait,
1151                     const struct nf_conntrack_expect *exp)
1152 {
1153         struct nlmsghdr *nlh;
1154         struct nfgenmsg *nfmsg;
1155         unsigned char *b = skb_tail_pointer(skb);
1156
1157         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1158         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1159         nfmsg  = NLMSG_DATA(nlh);
1160
1161         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1162         nfmsg->nfgen_family = exp->tuple.src.l3num;
1163         nfmsg->version      = NFNETLINK_V0;
1164         nfmsg->res_id       = 0;
1165
1166         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1167                 goto nfattr_failure;
1168
1169         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1170         return skb->len;
1171
1172 nlmsg_failure:
1173 nfattr_failure:
1174         nlmsg_trim(skb, b);
1175         return -1;
1176 }
1177
1178 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1179 static int ctnetlink_expect_event(struct notifier_block *this,
1180                                   unsigned long events, void *ptr)
1181 {
1182         struct nlmsghdr *nlh;
1183         struct nfgenmsg *nfmsg;
1184         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1185         struct sk_buff *skb;
1186         unsigned int type;
1187         sk_buff_data_t b;
1188         int flags = 0;
1189
1190         if (events & IPEXP_NEW) {
1191                 type = IPCTNL_MSG_EXP_NEW;
1192                 flags = NLM_F_CREATE|NLM_F_EXCL;
1193         } else
1194                 return NOTIFY_DONE;
1195
1196         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1197                 return NOTIFY_DONE;
1198
1199         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1200         if (!skb)
1201                 return NOTIFY_DONE;
1202
1203         b = skb->tail;
1204
1205         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1206         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1207         nfmsg = NLMSG_DATA(nlh);
1208
1209         nlh->nlmsg_flags    = flags;
1210         nfmsg->nfgen_family = exp->tuple.src.l3num;
1211         nfmsg->version      = NFNETLINK_V0;
1212         nfmsg->res_id       = 0;
1213
1214         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1215                 goto nfattr_failure;
1216
1217         nlh->nlmsg_len = skb->tail - b;
1218         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1219         return NOTIFY_DONE;
1220
1221 nlmsg_failure:
1222 nfattr_failure:
1223         kfree_skb(skb);
1224         return NOTIFY_DONE;
1225 }
1226 #endif
1227
1228 static int
1229 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1230 {
1231         struct nf_conntrack_expect *exp = NULL;
1232         struct list_head *i;
1233         u_int32_t *id = (u_int32_t *) &cb->args[0];
1234         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1235         u_int8_t l3proto = nfmsg->nfgen_family;
1236
1237         read_lock_bh(&nf_conntrack_lock);
1238         list_for_each_prev(i, &nf_conntrack_expect_list) {
1239                 exp = (struct nf_conntrack_expect *) i;
1240                 if (l3proto && exp->tuple.src.l3num != l3proto)
1241                         continue;
1242                 if (exp->id <= *id)
1243                         continue;
1244                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1245                                             cb->nlh->nlmsg_seq,
1246                                             IPCTNL_MSG_EXP_NEW,
1247                                             1, exp) < 0)
1248                         goto out;
1249                 *id = exp->id;
1250         }
1251 out:
1252         read_unlock_bh(&nf_conntrack_lock);
1253
1254         return skb->len;
1255 }
1256
1257 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1258         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1259         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1260 };
1261
1262 static int
1263 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1264                      struct nlmsghdr *nlh, struct nfattr *cda[])
1265 {
1266         struct nf_conntrack_tuple tuple;
1267         struct nf_conntrack_expect *exp;
1268         struct sk_buff *skb2;
1269         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1270         u_int8_t u3 = nfmsg->nfgen_family;
1271         int err = 0;
1272
1273         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1274                 return -EINVAL;
1275
1276         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1277                 return netlink_dump_start(ctnl, skb, nlh,
1278                                           ctnetlink_exp_dump_table,
1279                                           ctnetlink_done);
1280         }
1281
1282         if (cda[CTA_EXPECT_MASTER-1])
1283                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1284         else
1285                 return -EINVAL;
1286
1287         if (err < 0)
1288                 return err;
1289
1290         exp = nf_conntrack_expect_find_get(&tuple);
1291         if (!exp)
1292                 return -ENOENT;
1293
1294         if (cda[CTA_EXPECT_ID-1]) {
1295                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1296                 if (exp->id != ntohl(id)) {
1297                         nf_conntrack_expect_put(exp);
1298                         return -ENOENT;
1299                 }
1300         }
1301
1302         err = -ENOMEM;
1303         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1304         if (!skb2)
1305                 goto out;
1306
1307         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1308                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1309                                       1, exp);
1310         if (err <= 0)
1311                 goto free;
1312
1313         nf_conntrack_expect_put(exp);
1314
1315         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1316
1317 free:
1318         kfree_skb(skb2);
1319 out:
1320         nf_conntrack_expect_put(exp);
1321         return err;
1322 }
1323
1324 static int
1325 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1326                      struct nlmsghdr *nlh, struct nfattr *cda[])
1327 {
1328         struct nf_conntrack_expect *exp, *tmp;
1329         struct nf_conntrack_tuple tuple;
1330         struct nf_conntrack_helper *h;
1331         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1332         u_int8_t u3 = nfmsg->nfgen_family;
1333         int err;
1334
1335         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1336                 return -EINVAL;
1337
1338         if (cda[CTA_EXPECT_TUPLE-1]) {
1339                 /* delete a single expect by tuple */
1340                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1341                 if (err < 0)
1342                         return err;
1343
1344                 /* bump usage count to 2 */
1345                 exp = nf_conntrack_expect_find_get(&tuple);
1346                 if (!exp)
1347                         return -ENOENT;
1348
1349                 if (cda[CTA_EXPECT_ID-1]) {
1350                         __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1351                         if (exp->id != ntohl(id)) {
1352                                 nf_conntrack_expect_put(exp);
1353                                 return -ENOENT;
1354                         }
1355                 }
1356
1357                 /* after list removal, usage count == 1 */
1358                 nf_conntrack_unexpect_related(exp);
1359                 /* have to put what we 'get' above.
1360                  * after this line usage count == 0 */
1361                 nf_conntrack_expect_put(exp);
1362         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1363                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1364
1365                 /* delete all expectations for this helper */
1366                 write_lock_bh(&nf_conntrack_lock);
1367                 h = __nf_conntrack_helper_find_byname(name);
1368                 if (!h) {
1369                         write_unlock_bh(&nf_conntrack_lock);
1370                         return -EINVAL;
1371                 }
1372                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1373                                          list) {
1374                         struct nf_conn_help *m_help = nfct_help(exp->master);
1375                         if (m_help->helper == h
1376                             && del_timer(&exp->timeout)) {
1377                                 nf_ct_unlink_expect(exp);
1378                                 nf_conntrack_expect_put(exp);
1379                         }
1380                 }
1381                 write_unlock_bh(&nf_conntrack_lock);
1382         } else {
1383                 /* This basically means we have to flush everything*/
1384                 write_lock_bh(&nf_conntrack_lock);
1385                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1386                                          list) {
1387                         if (del_timer(&exp->timeout)) {
1388                                 nf_ct_unlink_expect(exp);
1389                                 nf_conntrack_expect_put(exp);
1390                         }
1391                 }
1392                 write_unlock_bh(&nf_conntrack_lock);
1393         }
1394
1395         return 0;
1396 }
1397 static int
1398 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1399 {
1400         return -EOPNOTSUPP;
1401 }
1402
1403 static int
1404 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1405 {
1406         struct nf_conntrack_tuple tuple, mask, master_tuple;
1407         struct nf_conntrack_tuple_hash *h = NULL;
1408         struct nf_conntrack_expect *exp;
1409         struct nf_conn *ct;
1410         struct nf_conn_help *help;
1411         int err = 0;
1412
1413         /* caller guarantees that those three CTA_EXPECT_* exist */
1414         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1415         if (err < 0)
1416                 return err;
1417         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1418         if (err < 0)
1419                 return err;
1420         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1421         if (err < 0)
1422                 return err;
1423
1424         /* Look for master conntrack of this expectation */
1425         h = nf_conntrack_find_get(&master_tuple, NULL);
1426         if (!h)
1427                 return -ENOENT;
1428         ct = nf_ct_tuplehash_to_ctrack(h);
1429         help = nfct_help(ct);
1430
1431         if (!help || !help->helper) {
1432                 /* such conntrack hasn't got any helper, abort */
1433                 err = -EINVAL;
1434                 goto out;
1435         }
1436
1437         exp = nf_conntrack_expect_alloc(ct);
1438         if (!exp) {
1439                 err = -ENOMEM;
1440                 goto out;
1441         }
1442
1443         exp->expectfn = NULL;
1444         exp->flags = 0;
1445         exp->master = ct;
1446         exp->helper = NULL;
1447         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1448         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1449
1450         err = nf_conntrack_expect_related(exp);
1451         nf_conntrack_expect_put(exp);
1452
1453 out:
1454         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1455         return err;
1456 }
1457
1458 static int
1459 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1460                      struct nlmsghdr *nlh, struct nfattr *cda[])
1461 {
1462         struct nf_conntrack_tuple tuple;
1463         struct nf_conntrack_expect *exp;
1464         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1465         u_int8_t u3 = nfmsg->nfgen_family;
1466         int err = 0;
1467
1468         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1469                 return -EINVAL;
1470
1471         if (!cda[CTA_EXPECT_TUPLE-1]
1472             || !cda[CTA_EXPECT_MASK-1]
1473             || !cda[CTA_EXPECT_MASTER-1])
1474                 return -EINVAL;
1475
1476         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1477         if (err < 0)
1478                 return err;
1479
1480         write_lock_bh(&nf_conntrack_lock);
1481         exp = __nf_conntrack_expect_find(&tuple);
1482
1483         if (!exp) {
1484                 write_unlock_bh(&nf_conntrack_lock);
1485                 err = -ENOENT;
1486                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1487                         err = ctnetlink_create_expect(cda, u3);
1488                 return err;
1489         }
1490
1491         err = -EEXIST;
1492         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1493                 err = ctnetlink_change_expect(exp, cda);
1494         write_unlock_bh(&nf_conntrack_lock);
1495
1496         return err;
1497 }
1498
1499 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1500 static struct notifier_block ctnl_notifier = {
1501         .notifier_call  = ctnetlink_conntrack_event,
1502 };
1503
1504 static struct notifier_block ctnl_notifier_exp = {
1505         .notifier_call  = ctnetlink_expect_event,
1506 };
1507 #endif
1508
1509 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1510         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1511                                             .attr_count = CTA_MAX, },
1512         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1513                                             .attr_count = CTA_MAX, },
1514         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1515                                             .attr_count = CTA_MAX, },
1516         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1517                                             .attr_count = CTA_MAX, },
1518 };
1519
1520 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1521         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1522                                             .attr_count = CTA_EXPECT_MAX, },
1523         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1524                                             .attr_count = CTA_EXPECT_MAX, },
1525         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1526                                             .attr_count = CTA_EXPECT_MAX, },
1527 };
1528
1529 static struct nfnetlink_subsystem ctnl_subsys = {
1530         .name                           = "conntrack",
1531         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1532         .cb_count                       = IPCTNL_MSG_MAX,
1533         .cb                             = ctnl_cb,
1534 };
1535
1536 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1537         .name                           = "conntrack_expect",
1538         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1539         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1540         .cb                             = ctnl_exp_cb,
1541 };
1542
1543 MODULE_ALIAS("ip_conntrack_netlink");
1544 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1545 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1546
1547 static int __init ctnetlink_init(void)
1548 {
1549         int ret;
1550
1551         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1552         ret = nfnetlink_subsys_register(&ctnl_subsys);
1553         if (ret < 0) {
1554                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1555                 goto err_out;
1556         }
1557
1558         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1559         if (ret < 0) {
1560                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1561                 goto err_unreg_subsys;
1562         }
1563
1564 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1565         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1566         if (ret < 0) {
1567                 printk("ctnetlink_init: cannot register notifier.\n");
1568                 goto err_unreg_exp_subsys;
1569         }
1570
1571         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1572         if (ret < 0) {
1573                 printk("ctnetlink_init: cannot expect register notifier.\n");
1574                 goto err_unreg_notifier;
1575         }
1576 #endif
1577
1578         return 0;
1579
1580 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1581 err_unreg_notifier:
1582         nf_conntrack_unregister_notifier(&ctnl_notifier);
1583 err_unreg_exp_subsys:
1584         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1585 #endif
1586 err_unreg_subsys:
1587         nfnetlink_subsys_unregister(&ctnl_subsys);
1588 err_out:
1589         return ret;
1590 }
1591
1592 static void __exit ctnetlink_exit(void)
1593 {
1594         printk("ctnetlink: unregistering from nfnetlink.\n");
1595
1596 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1597         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1598         nf_conntrack_unregister_notifier(&ctnl_notifier);
1599 #endif
1600
1601         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1602         nfnetlink_subsys_unregister(&ctnl_subsys);
1603         return;
1604 }
1605
1606 module_init(ctnetlink_init);
1607 module_exit(ctnetlink_exit);