[NETLINK]: Remove error pointer from netlink message handler
[linux-2.6.git] / 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  * I've reworked this stuff to use attributes instead of conntrack
10  * structures. 5.44 am. I need more tea. --pablo 05/07/11.
11  *
12  * Initial connection tracking via netlink development funded and
13  * generally made possible by Network Robots, Inc. (www.networkrobots.com)
14  *
15  * Further development of this code funded by Astaro AG (http://www.astaro.com)
16  *
17  * This software may be used and distributed according to the terms
18  * of the GNU General Public License, incorporated herein by reference.
19  *
20  * Derived from ip_conntrack_netlink.c: Port by Pablo Neira Ayuso (05/11/14)
21  */
22
23 #include <linux/init.h>
24 #include <linux/module.h>
25 #include <linux/kernel.h>
26 #include <linux/types.h>
27 #include <linux/timer.h>
28 #include <linux/skbuff.h>
29 #include <linux/errno.h>
30 #include <linux/netlink.h>
31 #include <linux/spinlock.h>
32 #include <linux/interrupt.h>
33 #include <linux/notifier.h>
34
35 #include <linux/netfilter.h>
36 #include <net/netlink.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_l3proto.h>
42 #include <net/netfilter/nf_conntrack_l4proto.h>
43 #include <net/netfilter/nf_conntrack_tuple.h>
44 #ifdef CONFIG_NF_NAT_NEEDED
45 #include <net/netfilter/nf_nat_core.h>
46 #include <net/netfilter/nf_nat_protocol.h>
47 #endif
48
49 #include <linux/netfilter/nfnetlink.h>
50 #include <linux/netfilter/nfnetlink_conntrack.h>
51
52 MODULE_LICENSE("GPL");
53
54 static char __initdata version[] = "0.93";
55
56 static inline int
57 ctnetlink_dump_tuples_proto(struct sk_buff *skb,
58                             const struct nf_conntrack_tuple *tuple,
59                             struct nf_conntrack_l4proto *l4proto)
60 {
61         int ret = 0;
62         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_PROTO);
63
64         NFA_PUT(skb, CTA_PROTO_NUM, sizeof(u_int8_t), &tuple->dst.protonum);
65
66         if (likely(l4proto->tuple_to_nfattr))
67                 ret = l4proto->tuple_to_nfattr(skb, tuple);
68
69         NFA_NEST_END(skb, nest_parms);
70
71         return ret;
72
73 nfattr_failure:
74         return -1;
75 }
76
77 static inline int
78 ctnetlink_dump_tuples_ip(struct sk_buff *skb,
79                          const struct nf_conntrack_tuple *tuple,
80                          struct nf_conntrack_l3proto *l3proto)
81 {
82         int ret = 0;
83         struct nfattr *nest_parms = NFA_NEST(skb, CTA_TUPLE_IP);
84
85         if (likely(l3proto->tuple_to_nfattr))
86                 ret = l3proto->tuple_to_nfattr(skb, tuple);
87
88         NFA_NEST_END(skb, nest_parms);
89
90         return ret;
91
92 nfattr_failure:
93         return -1;
94 }
95
96 static inline int
97 ctnetlink_dump_tuples(struct sk_buff *skb,
98                       const struct nf_conntrack_tuple *tuple)
99 {
100         int ret;
101         struct nf_conntrack_l3proto *l3proto;
102         struct nf_conntrack_l4proto *l4proto;
103
104         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
105         ret = ctnetlink_dump_tuples_ip(skb, tuple, l3proto);
106         nf_ct_l3proto_put(l3proto);
107
108         if (unlikely(ret < 0))
109                 return ret;
110
111         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
112         ret = ctnetlink_dump_tuples_proto(skb, tuple, l4proto);
113         nf_ct_l4proto_put(l4proto);
114
115         return ret;
116 }
117
118 static inline int
119 ctnetlink_dump_status(struct sk_buff *skb, const struct nf_conn *ct)
120 {
121         __be32 status = htonl((u_int32_t) ct->status);
122         NFA_PUT(skb, CTA_STATUS, sizeof(status), &status);
123         return 0;
124
125 nfattr_failure:
126         return -1;
127 }
128
129 static inline int
130 ctnetlink_dump_timeout(struct sk_buff *skb, const struct nf_conn *ct)
131 {
132         long timeout_l = ct->timeout.expires - jiffies;
133         __be32 timeout;
134
135         if (timeout_l < 0)
136                 timeout = 0;
137         else
138                 timeout = htonl(timeout_l / HZ);
139
140         NFA_PUT(skb, CTA_TIMEOUT, sizeof(timeout), &timeout);
141         return 0;
142
143 nfattr_failure:
144         return -1;
145 }
146
147 static inline int
148 ctnetlink_dump_protoinfo(struct sk_buff *skb, const struct nf_conn *ct)
149 {
150         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);
151         struct nfattr *nest_proto;
152         int ret;
153
154         if (!l4proto->to_nfattr) {
155                 nf_ct_l4proto_put(l4proto);
156                 return 0;
157         }
158
159         nest_proto = NFA_NEST(skb, CTA_PROTOINFO);
160
161         ret = l4proto->to_nfattr(skb, nest_proto, ct);
162
163         nf_ct_l4proto_put(l4proto);
164
165         NFA_NEST_END(skb, nest_proto);
166
167         return ret;
168
169 nfattr_failure:
170         nf_ct_l4proto_put(l4proto);
171         return -1;
172 }
173
174 static inline int
175 ctnetlink_dump_helpinfo(struct sk_buff *skb, const struct nf_conn *ct)
176 {
177         struct nfattr *nest_helper;
178         const struct nf_conn_help *help = nfct_help(ct);
179
180         if (!help || !help->helper)
181                 return 0;
182
183         nest_helper = NFA_NEST(skb, CTA_HELP);
184         NFA_PUT(skb, CTA_HELP_NAME, strlen(help->helper->name), help->helper->name);
185
186         if (help->helper->to_nfattr)
187                 help->helper->to_nfattr(skb, ct);
188
189         NFA_NEST_END(skb, nest_helper);
190
191         return 0;
192
193 nfattr_failure:
194         return -1;
195 }
196
197 #ifdef CONFIG_NF_CT_ACCT
198 static inline int
199 ctnetlink_dump_counters(struct sk_buff *skb, const struct nf_conn *ct,
200                         enum ip_conntrack_dir dir)
201 {
202         enum ctattr_type type = dir ? CTA_COUNTERS_REPLY: CTA_COUNTERS_ORIG;
203         struct nfattr *nest_count = NFA_NEST(skb, type);
204         __be32 tmp;
205
206         tmp = htonl(ct->counters[dir].packets);
207         NFA_PUT(skb, CTA_COUNTERS32_PACKETS, sizeof(u_int32_t), &tmp);
208
209         tmp = htonl(ct->counters[dir].bytes);
210         NFA_PUT(skb, CTA_COUNTERS32_BYTES, sizeof(u_int32_t), &tmp);
211
212         NFA_NEST_END(skb, nest_count);
213
214         return 0;
215
216 nfattr_failure:
217         return -1;
218 }
219 #else
220 #define ctnetlink_dump_counters(a, b, c) (0)
221 #endif
222
223 #ifdef CONFIG_NF_CONNTRACK_MARK
224 static inline int
225 ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
226 {
227         __be32 mark = htonl(ct->mark);
228
229         NFA_PUT(skb, CTA_MARK, sizeof(u_int32_t), &mark);
230         return 0;
231
232 nfattr_failure:
233         return -1;
234 }
235 #else
236 #define ctnetlink_dump_mark(a, b) (0)
237 #endif
238
239 static inline int
240 ctnetlink_dump_id(struct sk_buff *skb, const struct nf_conn *ct)
241 {
242         __be32 id = htonl(ct->id);
243         NFA_PUT(skb, CTA_ID, sizeof(u_int32_t), &id);
244         return 0;
245
246 nfattr_failure:
247         return -1;
248 }
249
250 static inline int
251 ctnetlink_dump_use(struct sk_buff *skb, const struct nf_conn *ct)
252 {
253         __be32 use = htonl(atomic_read(&ct->ct_general.use));
254
255         NFA_PUT(skb, CTA_USE, sizeof(u_int32_t), &use);
256         return 0;
257
258 nfattr_failure:
259         return -1;
260 }
261
262 #define tuple(ct, dir) (&(ct)->tuplehash[dir].tuple)
263
264 static int
265 ctnetlink_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
266                     int event, int nowait,
267                     const struct nf_conn *ct)
268 {
269         struct nlmsghdr *nlh;
270         struct nfgenmsg *nfmsg;
271         struct nfattr *nest_parms;
272         unsigned char *b = skb_tail_pointer(skb);
273
274         event |= NFNL_SUBSYS_CTNETLINK << 8;
275         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
276         nfmsg  = NLMSG_DATA(nlh);
277
278         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
279         nfmsg->nfgen_family =
280                 ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
281         nfmsg->version      = NFNETLINK_V0;
282         nfmsg->res_id       = 0;
283
284         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
285         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
286                 goto nfattr_failure;
287         NFA_NEST_END(skb, nest_parms);
288
289         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
290         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
291                 goto nfattr_failure;
292         NFA_NEST_END(skb, nest_parms);
293
294         if (ctnetlink_dump_status(skb, ct) < 0 ||
295             ctnetlink_dump_timeout(skb, ct) < 0 ||
296             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
297             ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0 ||
298             ctnetlink_dump_protoinfo(skb, ct) < 0 ||
299             ctnetlink_dump_helpinfo(skb, ct) < 0 ||
300             ctnetlink_dump_mark(skb, ct) < 0 ||
301             ctnetlink_dump_id(skb, ct) < 0 ||
302             ctnetlink_dump_use(skb, ct) < 0)
303                 goto nfattr_failure;
304
305         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
306         return skb->len;
307
308 nlmsg_failure:
309 nfattr_failure:
310         nlmsg_trim(skb, b);
311         return -1;
312 }
313
314 #ifdef CONFIG_NF_CONNTRACK_EVENTS
315 static int ctnetlink_conntrack_event(struct notifier_block *this,
316                                      unsigned long events, void *ptr)
317 {
318         struct nlmsghdr *nlh;
319         struct nfgenmsg *nfmsg;
320         struct nfattr *nest_parms;
321         struct nf_conn *ct = (struct nf_conn *)ptr;
322         struct sk_buff *skb;
323         unsigned int type;
324         sk_buff_data_t b;
325         unsigned int flags = 0, group;
326
327         /* ignore our fake conntrack entry */
328         if (ct == &nf_conntrack_untracked)
329                 return NOTIFY_DONE;
330
331         if (events & IPCT_DESTROY) {
332                 type = IPCTNL_MSG_CT_DELETE;
333                 group = NFNLGRP_CONNTRACK_DESTROY;
334         } else  if (events & (IPCT_NEW | IPCT_RELATED)) {
335                 type = IPCTNL_MSG_CT_NEW;
336                 flags = NLM_F_CREATE|NLM_F_EXCL;
337                 group = NFNLGRP_CONNTRACK_NEW;
338         } else  if (events & (IPCT_STATUS | IPCT_PROTOINFO)) {
339                 type = IPCTNL_MSG_CT_NEW;
340                 group = NFNLGRP_CONNTRACK_UPDATE;
341         } else
342                 return NOTIFY_DONE;
343
344         if (!nfnetlink_has_listeners(group))
345                 return NOTIFY_DONE;
346
347         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
348         if (!skb)
349                 return NOTIFY_DONE;
350
351         b = skb->tail;
352
353         type |= NFNL_SUBSYS_CTNETLINK << 8;
354         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
355         nfmsg = NLMSG_DATA(nlh);
356
357         nlh->nlmsg_flags    = flags;
358         nfmsg->nfgen_family = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
359         nfmsg->version  = NFNETLINK_V0;
360         nfmsg->res_id   = 0;
361
362         nest_parms = NFA_NEST(skb, CTA_TUPLE_ORIG);
363         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_ORIGINAL)) < 0)
364                 goto nfattr_failure;
365         NFA_NEST_END(skb, nest_parms);
366
367         nest_parms = NFA_NEST(skb, CTA_TUPLE_REPLY);
368         if (ctnetlink_dump_tuples(skb, tuple(ct, IP_CT_DIR_REPLY)) < 0)
369                 goto nfattr_failure;
370         NFA_NEST_END(skb, nest_parms);
371
372         if (events & IPCT_DESTROY) {
373                 if (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
374                     ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0)
375                         goto nfattr_failure;
376         } else {
377                 if (ctnetlink_dump_status(skb, ct) < 0)
378                         goto nfattr_failure;
379
380                 if (ctnetlink_dump_timeout(skb, ct) < 0)
381                         goto nfattr_failure;
382
383                 if (events & IPCT_PROTOINFO
384                     && ctnetlink_dump_protoinfo(skb, ct) < 0)
385                         goto nfattr_failure;
386
387                 if ((events & IPCT_HELPER || nfct_help(ct))
388                     && ctnetlink_dump_helpinfo(skb, ct) < 0)
389                         goto nfattr_failure;
390
391 #ifdef CONFIG_NF_CONNTRACK_MARK
392                 if ((events & IPCT_MARK || ct->mark)
393                     && ctnetlink_dump_mark(skb, ct) < 0)
394                         goto nfattr_failure;
395 #endif
396
397                 if (events & IPCT_COUNTER_FILLING &&
398                     (ctnetlink_dump_counters(skb, ct, IP_CT_DIR_ORIGINAL) < 0 ||
399                      ctnetlink_dump_counters(skb, ct, IP_CT_DIR_REPLY) < 0))
400                         goto nfattr_failure;
401         }
402
403         nlh->nlmsg_len = skb->tail - b;
404         nfnetlink_send(skb, 0, group, 0);
405         return NOTIFY_DONE;
406
407 nlmsg_failure:
408 nfattr_failure:
409         kfree_skb(skb);
410         return NOTIFY_DONE;
411 }
412 #endif /* CONFIG_NF_CONNTRACK_EVENTS */
413
414 static int ctnetlink_done(struct netlink_callback *cb)
415 {
416         if (cb->args[1])
417                 nf_ct_put((struct nf_conn *)cb->args[1]);
418         return 0;
419 }
420
421 #define L3PROTO(ct) ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num
422
423 static int
424 ctnetlink_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
425 {
426         struct nf_conn *ct, *last;
427         struct nf_conntrack_tuple_hash *h;
428         struct list_head *i;
429         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
430         u_int8_t l3proto = nfmsg->nfgen_family;
431
432         read_lock_bh(&nf_conntrack_lock);
433         last = (struct nf_conn *)cb->args[1];
434         for (; cb->args[0] < nf_conntrack_htable_size; cb->args[0]++) {
435 restart:
436                 list_for_each_prev(i, &nf_conntrack_hash[cb->args[0]]) {
437                         h = (struct nf_conntrack_tuple_hash *) i;
438                         if (NF_CT_DIRECTION(h) != IP_CT_DIR_ORIGINAL)
439                                 continue;
440                         ct = nf_ct_tuplehash_to_ctrack(h);
441                         /* Dump entries of a given L3 protocol number.
442                          * If it is not specified, ie. l3proto == 0,
443                          * then dump everything. */
444                         if (l3proto && L3PROTO(ct) != l3proto)
445                                 continue;
446                         if (cb->args[1]) {
447                                 if (ct != last)
448                                         continue;
449                                 cb->args[1] = 0;
450                         }
451                         if (ctnetlink_fill_info(skb, NETLINK_CB(cb->skb).pid,
452                                                 cb->nlh->nlmsg_seq,
453                                                 IPCTNL_MSG_CT_NEW,
454                                                 1, ct) < 0) {
455                                 nf_conntrack_get(&ct->ct_general);
456                                 cb->args[1] = (unsigned long)ct;
457                                 goto out;
458                         }
459 #ifdef CONFIG_NF_CT_ACCT
460                         if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) ==
461                                                 IPCTNL_MSG_CT_GET_CTRZERO)
462                                 memset(&ct->counters, 0, sizeof(ct->counters));
463 #endif
464                 }
465                 if (cb->args[1]) {
466                         cb->args[1] = 0;
467                         goto restart;
468                 }
469         }
470 out:
471         read_unlock_bh(&nf_conntrack_lock);
472         if (last)
473                 nf_ct_put(last);
474
475         return skb->len;
476 }
477
478 static inline int
479 ctnetlink_parse_tuple_ip(struct nfattr *attr, struct nf_conntrack_tuple *tuple)
480 {
481         struct nfattr *tb[CTA_IP_MAX];
482         struct nf_conntrack_l3proto *l3proto;
483         int ret = 0;
484
485         nfattr_parse_nested(tb, CTA_IP_MAX, attr);
486
487         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
488
489         if (likely(l3proto->nfattr_to_tuple))
490                 ret = l3proto->nfattr_to_tuple(tb, tuple);
491
492         nf_ct_l3proto_put(l3proto);
493
494         return ret;
495 }
496
497 static const size_t cta_min_proto[CTA_PROTO_MAX] = {
498         [CTA_PROTO_NUM-1]       = sizeof(u_int8_t),
499 };
500
501 static inline int
502 ctnetlink_parse_tuple_proto(struct nfattr *attr,
503                             struct nf_conntrack_tuple *tuple)
504 {
505         struct nfattr *tb[CTA_PROTO_MAX];
506         struct nf_conntrack_l4proto *l4proto;
507         int ret = 0;
508
509         nfattr_parse_nested(tb, CTA_PROTO_MAX, attr);
510
511         if (nfattr_bad_size(tb, CTA_PROTO_MAX, cta_min_proto))
512                 return -EINVAL;
513
514         if (!tb[CTA_PROTO_NUM-1])
515                 return -EINVAL;
516         tuple->dst.protonum = *(u_int8_t *)NFA_DATA(tb[CTA_PROTO_NUM-1]);
517
518         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
519
520         if (likely(l4proto->nfattr_to_tuple))
521                 ret = l4proto->nfattr_to_tuple(tb, tuple);
522
523         nf_ct_l4proto_put(l4proto);
524
525         return ret;
526 }
527
528 static inline int
529 ctnetlink_parse_tuple(struct nfattr *cda[], struct nf_conntrack_tuple *tuple,
530                       enum ctattr_tuple type, u_int8_t l3num)
531 {
532         struct nfattr *tb[CTA_TUPLE_MAX];
533         int err;
534
535         memset(tuple, 0, sizeof(*tuple));
536
537         nfattr_parse_nested(tb, CTA_TUPLE_MAX, cda[type-1]);
538
539         if (!tb[CTA_TUPLE_IP-1])
540                 return -EINVAL;
541
542         tuple->src.l3num = l3num;
543
544         err = ctnetlink_parse_tuple_ip(tb[CTA_TUPLE_IP-1], tuple);
545         if (err < 0)
546                 return err;
547
548         if (!tb[CTA_TUPLE_PROTO-1])
549                 return -EINVAL;
550
551         err = ctnetlink_parse_tuple_proto(tb[CTA_TUPLE_PROTO-1], tuple);
552         if (err < 0)
553                 return err;
554
555         /* orig and expect tuples get DIR_ORIGINAL */
556         if (type == CTA_TUPLE_REPLY)
557                 tuple->dst.dir = IP_CT_DIR_REPLY;
558         else
559                 tuple->dst.dir = IP_CT_DIR_ORIGINAL;
560
561         return 0;
562 }
563
564 #ifdef CONFIG_NF_NAT_NEEDED
565 static const size_t cta_min_protonat[CTA_PROTONAT_MAX] = {
566         [CTA_PROTONAT_PORT_MIN-1]       = sizeof(u_int16_t),
567         [CTA_PROTONAT_PORT_MAX-1]       = sizeof(u_int16_t),
568 };
569
570 static int nfnetlink_parse_nat_proto(struct nfattr *attr,
571                                      const struct nf_conn *ct,
572                                      struct nf_nat_range *range)
573 {
574         struct nfattr *tb[CTA_PROTONAT_MAX];
575         struct nf_nat_protocol *npt;
576
577         nfattr_parse_nested(tb, CTA_PROTONAT_MAX, attr);
578
579         if (nfattr_bad_size(tb, CTA_PROTONAT_MAX, cta_min_protonat))
580                 return -EINVAL;
581
582         npt = nf_nat_proto_find_get(ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum);
583
584         if (!npt->nfattr_to_range) {
585                 nf_nat_proto_put(npt);
586                 return 0;
587         }
588
589         /* nfattr_to_range returns 1 if it parsed, 0 if not, neg. on error */
590         if (npt->nfattr_to_range(tb, range) > 0)
591                 range->flags |= IP_NAT_RANGE_PROTO_SPECIFIED;
592
593         nf_nat_proto_put(npt);
594
595         return 0;
596 }
597
598 static const size_t cta_min_nat[CTA_NAT_MAX] = {
599         [CTA_NAT_MINIP-1]       = sizeof(u_int32_t),
600         [CTA_NAT_MAXIP-1]       = sizeof(u_int32_t),
601 };
602
603 static inline int
604 nfnetlink_parse_nat(struct nfattr *nat,
605                     const struct nf_conn *ct, struct nf_nat_range *range)
606 {
607         struct nfattr *tb[CTA_NAT_MAX];
608         int err;
609
610         memset(range, 0, sizeof(*range));
611
612         nfattr_parse_nested(tb, CTA_NAT_MAX, nat);
613
614         if (nfattr_bad_size(tb, CTA_NAT_MAX, cta_min_nat))
615                 return -EINVAL;
616
617         if (tb[CTA_NAT_MINIP-1])
618                 range->min_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MINIP-1]);
619
620         if (!tb[CTA_NAT_MAXIP-1])
621                 range->max_ip = range->min_ip;
622         else
623                 range->max_ip = *(__be32 *)NFA_DATA(tb[CTA_NAT_MAXIP-1]);
624
625         if (range->min_ip)
626                 range->flags |= IP_NAT_RANGE_MAP_IPS;
627
628         if (!tb[CTA_NAT_PROTO-1])
629                 return 0;
630
631         err = nfnetlink_parse_nat_proto(tb[CTA_NAT_PROTO-1], ct, range);
632         if (err < 0)
633                 return err;
634
635         return 0;
636 }
637 #endif
638
639 static inline int
640 ctnetlink_parse_help(struct nfattr *attr, char **helper_name)
641 {
642         struct nfattr *tb[CTA_HELP_MAX];
643
644         nfattr_parse_nested(tb, CTA_HELP_MAX, attr);
645
646         if (!tb[CTA_HELP_NAME-1])
647                 return -EINVAL;
648
649         *helper_name = NFA_DATA(tb[CTA_HELP_NAME-1]);
650
651         return 0;
652 }
653
654 static const size_t cta_min[CTA_MAX] = {
655         [CTA_STATUS-1]          = sizeof(u_int32_t),
656         [CTA_TIMEOUT-1]         = sizeof(u_int32_t),
657         [CTA_MARK-1]            = sizeof(u_int32_t),
658         [CTA_USE-1]             = sizeof(u_int32_t),
659         [CTA_ID-1]              = sizeof(u_int32_t)
660 };
661
662 static int
663 ctnetlink_del_conntrack(struct sock *ctnl, struct sk_buff *skb,
664                         struct nlmsghdr *nlh, struct nfattr *cda[])
665 {
666         struct nf_conntrack_tuple_hash *h;
667         struct nf_conntrack_tuple tuple;
668         struct nf_conn *ct;
669         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
670         u_int8_t u3 = nfmsg->nfgen_family;
671         int err = 0;
672
673         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
674                 return -EINVAL;
675
676         if (cda[CTA_TUPLE_ORIG-1])
677                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_ORIG, u3);
678         else if (cda[CTA_TUPLE_REPLY-1])
679                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_TUPLE_REPLY, u3);
680         else {
681                 /* Flush the whole table */
682                 nf_conntrack_flush();
683                 return 0;
684         }
685
686         if (err < 0)
687                 return err;
688
689         h = nf_conntrack_find_get(&tuple, NULL);
690         if (!h)
691                 return -ENOENT;
692
693         ct = nf_ct_tuplehash_to_ctrack(h);
694
695         if (cda[CTA_ID-1]) {
696                 u_int32_t id = ntohl(*(__be32 *)NFA_DATA(cda[CTA_ID-1]));
697                 if (ct->id != id) {
698                         nf_ct_put(ct);
699                         return -ENOENT;
700                 }
701         }
702         if (del_timer(&ct->timeout))
703                 ct->timeout.function((unsigned long)ct);
704
705         nf_ct_put(ct);
706
707         return 0;
708 }
709
710 static int
711 ctnetlink_get_conntrack(struct sock *ctnl, struct sk_buff *skb,
712                         struct nlmsghdr *nlh, struct nfattr *cda[])
713 {
714         struct nf_conntrack_tuple_hash *h;
715         struct nf_conntrack_tuple tuple;
716         struct nf_conn *ct;
717         struct sk_buff *skb2 = NULL;
718         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
719         u_int8_t u3 = nfmsg->nfgen_family;
720         int err = 0;
721
722         if (nlh->nlmsg_flags & NLM_F_DUMP) {
723 #ifndef CONFIG_NF_CT_ACCT
724                 if (NFNL_MSG_TYPE(nlh->nlmsg_type) == IPCTNL_MSG_CT_GET_CTRZERO)
725                         return -ENOTSUPP;
726 #endif
727                 err = netlink_dump_start(ctnl, skb, nlh, ctnetlink_dump_table,
728                                          ctnetlink_done);
729                 if (err == 0)
730                         err = -EINTR;
731                 return err;
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         if (!help) {
842                 /* FIXME: we need to reallocate and rehash */
843                 return -EBUSY;
844         }
845
846         /* don't change helper of sibling connections */
847         if (ct->master)
848                 return -EINVAL;
849
850         err = ctnetlink_parse_help(cda[CTA_HELP-1], &helpname);
851         if (err < 0)
852                 return err;
853
854         helper = __nf_conntrack_helper_find_byname(helpname);
855         if (!helper) {
856                 if (!strcmp(helpname, ""))
857                         helper = NULL;
858                 else
859                         return -EINVAL;
860         }
861
862         if (help->helper) {
863                 if (!helper) {
864                         /* we had a helper before ... */
865                         nf_ct_remove_expectations(ct);
866                         help->helper = NULL;
867                 } else {
868                         /* need to zero data of old helper */
869                         memset(&help->help, 0, sizeof(help->help));
870                 }
871         }
872
873         help->helper = helper;
874
875         return 0;
876 }
877
878 static inline int
879 ctnetlink_change_timeout(struct nf_conn *ct, struct nfattr *cda[])
880 {
881         u_int32_t timeout = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
882
883         if (!del_timer(&ct->timeout))
884                 return -ETIME;
885
886         ct->timeout.expires = jiffies + timeout * HZ;
887         add_timer(&ct->timeout);
888
889         return 0;
890 }
891
892 static inline int
893 ctnetlink_change_protoinfo(struct nf_conn *ct, struct nfattr *cda[])
894 {
895         struct nfattr *tb[CTA_PROTOINFO_MAX], *attr = cda[CTA_PROTOINFO-1];
896         struct nf_conntrack_l4proto *l4proto;
897         u_int16_t npt = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.protonum;
898         u_int16_t l3num = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num;
899         int err = 0;
900
901         nfattr_parse_nested(tb, CTA_PROTOINFO_MAX, attr);
902
903         l4proto = nf_ct_l4proto_find_get(l3num, npt);
904
905         if (l4proto->from_nfattr)
906                 err = l4proto->from_nfattr(tb, ct);
907         nf_ct_l4proto_put(l4proto);
908
909         return err;
910 }
911
912 static int
913 ctnetlink_change_conntrack(struct nf_conn *ct, struct nfattr *cda[])
914 {
915         int err;
916
917         if (cda[CTA_HELP-1]) {
918                 err = ctnetlink_change_helper(ct, cda);
919                 if (err < 0)
920                         return err;
921         }
922
923         if (cda[CTA_TIMEOUT-1]) {
924                 err = ctnetlink_change_timeout(ct, cda);
925                 if (err < 0)
926                         return err;
927         }
928
929         if (cda[CTA_STATUS-1]) {
930                 err = ctnetlink_change_status(ct, cda);
931                 if (err < 0)
932                         return err;
933         }
934
935         if (cda[CTA_PROTOINFO-1]) {
936                 err = ctnetlink_change_protoinfo(ct, cda);
937                 if (err < 0)
938                         return err;
939         }
940
941 #if defined(CONFIG_NF_CONNTRACK_MARK)
942         if (cda[CTA_MARK-1])
943                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
944 #endif
945
946         return 0;
947 }
948
949 static int
950 ctnetlink_create_conntrack(struct nfattr *cda[],
951                            struct nf_conntrack_tuple *otuple,
952                            struct nf_conntrack_tuple *rtuple)
953 {
954         struct nf_conn *ct;
955         int err = -EINVAL;
956         struct nf_conn_help *help;
957
958         ct = nf_conntrack_alloc(otuple, rtuple);
959         if (ct == NULL || IS_ERR(ct))
960                 return -ENOMEM;
961
962         if (!cda[CTA_TIMEOUT-1])
963                 goto err;
964         ct->timeout.expires = ntohl(*(__be32 *)NFA_DATA(cda[CTA_TIMEOUT-1]));
965
966         ct->timeout.expires = jiffies + ct->timeout.expires * HZ;
967         ct->status |= IPS_CONFIRMED;
968
969         if (cda[CTA_STATUS-1]) {
970                 err = ctnetlink_change_status(ct, cda);
971                 if (err < 0)
972                         goto err;
973         }
974
975         if (cda[CTA_PROTOINFO-1]) {
976                 err = ctnetlink_change_protoinfo(ct, cda);
977                 if (err < 0)
978                         goto err;
979         }
980
981 #if defined(CONFIG_NF_CONNTRACK_MARK)
982         if (cda[CTA_MARK-1])
983                 ct->mark = ntohl(*(__be32 *)NFA_DATA(cda[CTA_MARK-1]));
984 #endif
985
986         help = nfct_help(ct);
987         if (help)
988                 help->helper = nf_ct_helper_find_get(rtuple);
989
990         add_timer(&ct->timeout);
991         nf_conntrack_hash_insert(ct);
992
993         if (help && help->helper)
994                 nf_ct_helper_put(help->helper);
995
996         return 0;
997
998 err:
999         nf_conntrack_free(ct);
1000         return err;
1001 }
1002
1003 static int
1004 ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb,
1005                         struct nlmsghdr *nlh, struct nfattr *cda[])
1006 {
1007         struct nf_conntrack_tuple otuple, rtuple;
1008         struct nf_conntrack_tuple_hash *h = NULL;
1009         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1010         u_int8_t u3 = nfmsg->nfgen_family;
1011         int err = 0;
1012
1013         if (nfattr_bad_size(cda, CTA_MAX, cta_min))
1014                 return -EINVAL;
1015
1016         if (cda[CTA_TUPLE_ORIG-1]) {
1017                 err = ctnetlink_parse_tuple(cda, &otuple, CTA_TUPLE_ORIG, u3);
1018                 if (err < 0)
1019                         return err;
1020         }
1021
1022         if (cda[CTA_TUPLE_REPLY-1]) {
1023                 err = ctnetlink_parse_tuple(cda, &rtuple, CTA_TUPLE_REPLY, u3);
1024                 if (err < 0)
1025                         return err;
1026         }
1027
1028         write_lock_bh(&nf_conntrack_lock);
1029         if (cda[CTA_TUPLE_ORIG-1])
1030                 h = __nf_conntrack_find(&otuple, NULL);
1031         else if (cda[CTA_TUPLE_REPLY-1])
1032                 h = __nf_conntrack_find(&rtuple, NULL);
1033
1034         if (h == NULL) {
1035                 write_unlock_bh(&nf_conntrack_lock);
1036                 err = -ENOENT;
1037                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1038                         err = ctnetlink_create_conntrack(cda, &otuple, &rtuple);
1039                 return err;
1040         }
1041         /* implicit 'else' */
1042
1043         /* we only allow nat config for new conntracks */
1044         if (cda[CTA_NAT_SRC-1] || cda[CTA_NAT_DST-1]) {
1045                 err = -EINVAL;
1046                 goto out_unlock;
1047         }
1048
1049         /* We manipulate the conntrack inside the global conntrack table lock,
1050          * so there's no need to increase the refcount */
1051         err = -EEXIST;
1052         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1053                 err = ctnetlink_change_conntrack(nf_ct_tuplehash_to_ctrack(h), cda);
1054
1055 out_unlock:
1056         write_unlock_bh(&nf_conntrack_lock);
1057         return err;
1058 }
1059
1060 /***********************************************************************
1061  * EXPECT
1062  ***********************************************************************/
1063
1064 static inline int
1065 ctnetlink_exp_dump_tuple(struct sk_buff *skb,
1066                          const struct nf_conntrack_tuple *tuple,
1067                          enum ctattr_expect type)
1068 {
1069         struct nfattr *nest_parms = NFA_NEST(skb, type);
1070
1071         if (ctnetlink_dump_tuples(skb, tuple) < 0)
1072                 goto nfattr_failure;
1073
1074         NFA_NEST_END(skb, nest_parms);
1075
1076         return 0;
1077
1078 nfattr_failure:
1079         return -1;
1080 }
1081
1082 static inline int
1083 ctnetlink_exp_dump_mask(struct sk_buff *skb,
1084                         const struct nf_conntrack_tuple *tuple,
1085                         const struct nf_conntrack_tuple *mask)
1086 {
1087         int ret;
1088         struct nf_conntrack_l3proto *l3proto;
1089         struct nf_conntrack_l4proto *l4proto;
1090         struct nfattr *nest_parms = NFA_NEST(skb, CTA_EXPECT_MASK);
1091
1092         l3proto = nf_ct_l3proto_find_get(tuple->src.l3num);
1093         ret = ctnetlink_dump_tuples_ip(skb, mask, l3proto);
1094         nf_ct_l3proto_put(l3proto);
1095
1096         if (unlikely(ret < 0))
1097                 goto nfattr_failure;
1098
1099         l4proto = nf_ct_l4proto_find_get(tuple->src.l3num, tuple->dst.protonum);
1100         ret = ctnetlink_dump_tuples_proto(skb, mask, l4proto);
1101         nf_ct_l4proto_put(l4proto);
1102         if (unlikely(ret < 0))
1103                 goto nfattr_failure;
1104
1105         NFA_NEST_END(skb, nest_parms);
1106
1107         return 0;
1108
1109 nfattr_failure:
1110         return -1;
1111 }
1112
1113 static inline int
1114 ctnetlink_exp_dump_expect(struct sk_buff *skb,
1115                           const struct nf_conntrack_expect *exp)
1116 {
1117         struct nf_conn *master = exp->master;
1118         __be32 timeout = htonl((exp->timeout.expires - jiffies) / HZ);
1119         __be32 id = htonl(exp->id);
1120
1121         if (ctnetlink_exp_dump_tuple(skb, &exp->tuple, CTA_EXPECT_TUPLE) < 0)
1122                 goto nfattr_failure;
1123         if (ctnetlink_exp_dump_mask(skb, &exp->tuple, &exp->mask) < 0)
1124                 goto nfattr_failure;
1125         if (ctnetlink_exp_dump_tuple(skb,
1126                                  &master->tuplehash[IP_CT_DIR_ORIGINAL].tuple,
1127                                  CTA_EXPECT_MASTER) < 0)
1128                 goto nfattr_failure;
1129
1130         NFA_PUT(skb, CTA_EXPECT_TIMEOUT, sizeof(timeout), &timeout);
1131         NFA_PUT(skb, CTA_EXPECT_ID, sizeof(u_int32_t), &id);
1132
1133         return 0;
1134
1135 nfattr_failure:
1136         return -1;
1137 }
1138
1139 static int
1140 ctnetlink_exp_fill_info(struct sk_buff *skb, u32 pid, u32 seq,
1141                     int event,
1142                     int nowait,
1143                     const struct nf_conntrack_expect *exp)
1144 {
1145         struct nlmsghdr *nlh;
1146         struct nfgenmsg *nfmsg;
1147         unsigned char *b = skb_tail_pointer(skb);
1148
1149         event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1150         nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
1151         nfmsg  = NLMSG_DATA(nlh);
1152
1153         nlh->nlmsg_flags    = (nowait && pid) ? NLM_F_MULTI : 0;
1154         nfmsg->nfgen_family = exp->tuple.src.l3num;
1155         nfmsg->version      = NFNETLINK_V0;
1156         nfmsg->res_id       = 0;
1157
1158         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1159                 goto nfattr_failure;
1160
1161         nlh->nlmsg_len = skb_tail_pointer(skb) - b;
1162         return skb->len;
1163
1164 nlmsg_failure:
1165 nfattr_failure:
1166         nlmsg_trim(skb, b);
1167         return -1;
1168 }
1169
1170 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1171 static int ctnetlink_expect_event(struct notifier_block *this,
1172                                   unsigned long events, void *ptr)
1173 {
1174         struct nlmsghdr *nlh;
1175         struct nfgenmsg *nfmsg;
1176         struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
1177         struct sk_buff *skb;
1178         unsigned int type;
1179         sk_buff_data_t b;
1180         int flags = 0;
1181
1182         if (events & IPEXP_NEW) {
1183                 type = IPCTNL_MSG_EXP_NEW;
1184                 flags = NLM_F_CREATE|NLM_F_EXCL;
1185         } else
1186                 return NOTIFY_DONE;
1187
1188         if (!nfnetlink_has_listeners(NFNLGRP_CONNTRACK_EXP_NEW))
1189                 return NOTIFY_DONE;
1190
1191         skb = alloc_skb(NLMSG_GOODSIZE, GFP_ATOMIC);
1192         if (!skb)
1193                 return NOTIFY_DONE;
1194
1195         b = skb->tail;
1196
1197         type |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
1198         nlh   = NLMSG_PUT(skb, 0, 0, type, sizeof(struct nfgenmsg));
1199         nfmsg = NLMSG_DATA(nlh);
1200
1201         nlh->nlmsg_flags    = flags;
1202         nfmsg->nfgen_family = exp->tuple.src.l3num;
1203         nfmsg->version      = NFNETLINK_V0;
1204         nfmsg->res_id       = 0;
1205
1206         if (ctnetlink_exp_dump_expect(skb, exp) < 0)
1207                 goto nfattr_failure;
1208
1209         nlh->nlmsg_len = skb->tail - b;
1210         nfnetlink_send(skb, 0, NFNLGRP_CONNTRACK_EXP_NEW, 0);
1211         return NOTIFY_DONE;
1212
1213 nlmsg_failure:
1214 nfattr_failure:
1215         kfree_skb(skb);
1216         return NOTIFY_DONE;
1217 }
1218 #endif
1219
1220 static int
1221 ctnetlink_exp_dump_table(struct sk_buff *skb, struct netlink_callback *cb)
1222 {
1223         struct nf_conntrack_expect *exp = NULL;
1224         struct list_head *i;
1225         u_int32_t *id = (u_int32_t *) &cb->args[0];
1226         struct nfgenmsg *nfmsg = NLMSG_DATA(cb->nlh);
1227         u_int8_t l3proto = nfmsg->nfgen_family;
1228
1229         read_lock_bh(&nf_conntrack_lock);
1230         list_for_each_prev(i, &nf_conntrack_expect_list) {
1231                 exp = (struct nf_conntrack_expect *) i;
1232                 if (l3proto && exp->tuple.src.l3num != l3proto)
1233                         continue;
1234                 if (exp->id <= *id)
1235                         continue;
1236                 if (ctnetlink_exp_fill_info(skb, NETLINK_CB(cb->skb).pid,
1237                                             cb->nlh->nlmsg_seq,
1238                                             IPCTNL_MSG_EXP_NEW,
1239                                             1, exp) < 0)
1240                         goto out;
1241                 *id = exp->id;
1242         }
1243 out:
1244         read_unlock_bh(&nf_conntrack_lock);
1245
1246         return skb->len;
1247 }
1248
1249 static const size_t cta_min_exp[CTA_EXPECT_MAX] = {
1250         [CTA_EXPECT_TIMEOUT-1]          = sizeof(u_int32_t),
1251         [CTA_EXPECT_ID-1]               = sizeof(u_int32_t)
1252 };
1253
1254 static int
1255 ctnetlink_get_expect(struct sock *ctnl, struct sk_buff *skb,
1256                      struct nlmsghdr *nlh, struct nfattr *cda[])
1257 {
1258         struct nf_conntrack_tuple tuple;
1259         struct nf_conntrack_expect *exp;
1260         struct sk_buff *skb2;
1261         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1262         u_int8_t u3 = nfmsg->nfgen_family;
1263         int err = 0;
1264
1265         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1266                 return -EINVAL;
1267
1268         if (nlh->nlmsg_flags & NLM_F_DUMP) {
1269                 err = netlink_dump_start(ctnl, skb, nlh,
1270                                          ctnetlink_exp_dump_table,
1271                                          ctnetlink_done);
1272                 if (err == 0)
1273                         err = -EINTR;
1274                 return err;
1275         }
1276
1277         if (cda[CTA_EXPECT_MASTER-1])
1278                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_MASTER, u3);
1279         else
1280                 return -EINVAL;
1281
1282         if (err < 0)
1283                 return err;
1284
1285         exp = nf_conntrack_expect_find_get(&tuple);
1286         if (!exp)
1287                 return -ENOENT;
1288
1289         if (cda[CTA_EXPECT_ID-1]) {
1290                 __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1291                 if (exp->id != ntohl(id)) {
1292                         nf_conntrack_expect_put(exp);
1293                         return -ENOENT;
1294                 }
1295         }
1296
1297         err = -ENOMEM;
1298         skb2 = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
1299         if (!skb2)
1300                 goto out;
1301
1302         err = ctnetlink_exp_fill_info(skb2, NETLINK_CB(skb).pid,
1303                                       nlh->nlmsg_seq, IPCTNL_MSG_EXP_NEW,
1304                                       1, exp);
1305         if (err <= 0)
1306                 goto free;
1307
1308         nf_conntrack_expect_put(exp);
1309
1310         return netlink_unicast(ctnl, skb2, NETLINK_CB(skb).pid, MSG_DONTWAIT);
1311
1312 free:
1313         kfree_skb(skb2);
1314 out:
1315         nf_conntrack_expect_put(exp);
1316         return err;
1317 }
1318
1319 static int
1320 ctnetlink_del_expect(struct sock *ctnl, struct sk_buff *skb,
1321                      struct nlmsghdr *nlh, struct nfattr *cda[])
1322 {
1323         struct nf_conntrack_expect *exp, *tmp;
1324         struct nf_conntrack_tuple tuple;
1325         struct nf_conntrack_helper *h;
1326         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1327         u_int8_t u3 = nfmsg->nfgen_family;
1328         int err;
1329
1330         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1331                 return -EINVAL;
1332
1333         if (cda[CTA_EXPECT_TUPLE-1]) {
1334                 /* delete a single expect by tuple */
1335                 err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1336                 if (err < 0)
1337                         return err;
1338
1339                 /* bump usage count to 2 */
1340                 exp = nf_conntrack_expect_find_get(&tuple);
1341                 if (!exp)
1342                         return -ENOENT;
1343
1344                 if (cda[CTA_EXPECT_ID-1]) {
1345                         __be32 id = *(__be32 *)NFA_DATA(cda[CTA_EXPECT_ID-1]);
1346                         if (exp->id != ntohl(id)) {
1347                                 nf_conntrack_expect_put(exp);
1348                                 return -ENOENT;
1349                         }
1350                 }
1351
1352                 /* after list removal, usage count == 1 */
1353                 nf_conntrack_unexpect_related(exp);
1354                 /* have to put what we 'get' above.
1355                  * after this line usage count == 0 */
1356                 nf_conntrack_expect_put(exp);
1357         } else if (cda[CTA_EXPECT_HELP_NAME-1]) {
1358                 char *name = NFA_DATA(cda[CTA_EXPECT_HELP_NAME-1]);
1359
1360                 /* delete all expectations for this helper */
1361                 write_lock_bh(&nf_conntrack_lock);
1362                 h = __nf_conntrack_helper_find_byname(name);
1363                 if (!h) {
1364                         write_unlock_bh(&nf_conntrack_lock);
1365                         return -EINVAL;
1366                 }
1367                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1368                                          list) {
1369                         struct nf_conn_help *m_help = nfct_help(exp->master);
1370                         if (m_help->helper == h
1371                             && del_timer(&exp->timeout)) {
1372                                 nf_ct_unlink_expect(exp);
1373                                 nf_conntrack_expect_put(exp);
1374                         }
1375                 }
1376                 write_unlock_bh(&nf_conntrack_lock);
1377         } else {
1378                 /* This basically means we have to flush everything*/
1379                 write_lock_bh(&nf_conntrack_lock);
1380                 list_for_each_entry_safe(exp, tmp, &nf_conntrack_expect_list,
1381                                          list) {
1382                         if (del_timer(&exp->timeout)) {
1383                                 nf_ct_unlink_expect(exp);
1384                                 nf_conntrack_expect_put(exp);
1385                         }
1386                 }
1387                 write_unlock_bh(&nf_conntrack_lock);
1388         }
1389
1390         return 0;
1391 }
1392 static int
1393 ctnetlink_change_expect(struct nf_conntrack_expect *x, struct nfattr *cda[])
1394 {
1395         return -EOPNOTSUPP;
1396 }
1397
1398 static int
1399 ctnetlink_create_expect(struct nfattr *cda[], u_int8_t u3)
1400 {
1401         struct nf_conntrack_tuple tuple, mask, master_tuple;
1402         struct nf_conntrack_tuple_hash *h = NULL;
1403         struct nf_conntrack_expect *exp;
1404         struct nf_conn *ct;
1405         struct nf_conn_help *help;
1406         int err = 0;
1407
1408         /* caller guarantees that those three CTA_EXPECT_* exist */
1409         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1410         if (err < 0)
1411                 return err;
1412         err = ctnetlink_parse_tuple(cda, &mask, CTA_EXPECT_MASK, u3);
1413         if (err < 0)
1414                 return err;
1415         err = ctnetlink_parse_tuple(cda, &master_tuple, CTA_EXPECT_MASTER, u3);
1416         if (err < 0)
1417                 return err;
1418
1419         /* Look for master conntrack of this expectation */
1420         h = nf_conntrack_find_get(&master_tuple, NULL);
1421         if (!h)
1422                 return -ENOENT;
1423         ct = nf_ct_tuplehash_to_ctrack(h);
1424         help = nfct_help(ct);
1425
1426         if (!help || !help->helper) {
1427                 /* such conntrack hasn't got any helper, abort */
1428                 err = -EINVAL;
1429                 goto out;
1430         }
1431
1432         exp = nf_conntrack_expect_alloc(ct);
1433         if (!exp) {
1434                 err = -ENOMEM;
1435                 goto out;
1436         }
1437
1438         exp->expectfn = NULL;
1439         exp->flags = 0;
1440         exp->master = ct;
1441         exp->helper = NULL;
1442         memcpy(&exp->tuple, &tuple, sizeof(struct nf_conntrack_tuple));
1443         memcpy(&exp->mask, &mask, sizeof(struct nf_conntrack_tuple));
1444
1445         err = nf_conntrack_expect_related(exp);
1446         nf_conntrack_expect_put(exp);
1447
1448 out:
1449         nf_ct_put(nf_ct_tuplehash_to_ctrack(h));
1450         return err;
1451 }
1452
1453 static int
1454 ctnetlink_new_expect(struct sock *ctnl, struct sk_buff *skb,
1455                      struct nlmsghdr *nlh, struct nfattr *cda[])
1456 {
1457         struct nf_conntrack_tuple tuple;
1458         struct nf_conntrack_expect *exp;
1459         struct nfgenmsg *nfmsg = NLMSG_DATA(nlh);
1460         u_int8_t u3 = nfmsg->nfgen_family;
1461         int err = 0;
1462
1463         if (nfattr_bad_size(cda, CTA_EXPECT_MAX, cta_min_exp))
1464                 return -EINVAL;
1465
1466         if (!cda[CTA_EXPECT_TUPLE-1]
1467             || !cda[CTA_EXPECT_MASK-1]
1468             || !cda[CTA_EXPECT_MASTER-1])
1469                 return -EINVAL;
1470
1471         err = ctnetlink_parse_tuple(cda, &tuple, CTA_EXPECT_TUPLE, u3);
1472         if (err < 0)
1473                 return err;
1474
1475         write_lock_bh(&nf_conntrack_lock);
1476         exp = __nf_conntrack_expect_find(&tuple);
1477
1478         if (!exp) {
1479                 write_unlock_bh(&nf_conntrack_lock);
1480                 err = -ENOENT;
1481                 if (nlh->nlmsg_flags & NLM_F_CREATE)
1482                         err = ctnetlink_create_expect(cda, u3);
1483                 return err;
1484         }
1485
1486         err = -EEXIST;
1487         if (!(nlh->nlmsg_flags & NLM_F_EXCL))
1488                 err = ctnetlink_change_expect(exp, cda);
1489         write_unlock_bh(&nf_conntrack_lock);
1490
1491         return err;
1492 }
1493
1494 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1495 static struct notifier_block ctnl_notifier = {
1496         .notifier_call  = ctnetlink_conntrack_event,
1497 };
1498
1499 static struct notifier_block ctnl_notifier_exp = {
1500         .notifier_call  = ctnetlink_expect_event,
1501 };
1502 #endif
1503
1504 static struct nfnl_callback ctnl_cb[IPCTNL_MSG_MAX] = {
1505         [IPCTNL_MSG_CT_NEW]             = { .call = ctnetlink_new_conntrack,
1506                                             .attr_count = CTA_MAX, },
1507         [IPCTNL_MSG_CT_GET]             = { .call = ctnetlink_get_conntrack,
1508                                             .attr_count = CTA_MAX, },
1509         [IPCTNL_MSG_CT_DELETE]          = { .call = ctnetlink_del_conntrack,
1510                                             .attr_count = CTA_MAX, },
1511         [IPCTNL_MSG_CT_GET_CTRZERO]     = { .call = ctnetlink_get_conntrack,
1512                                             .attr_count = CTA_MAX, },
1513 };
1514
1515 static struct nfnl_callback ctnl_exp_cb[IPCTNL_MSG_EXP_MAX] = {
1516         [IPCTNL_MSG_EXP_GET]            = { .call = ctnetlink_get_expect,
1517                                             .attr_count = CTA_EXPECT_MAX, },
1518         [IPCTNL_MSG_EXP_NEW]            = { .call = ctnetlink_new_expect,
1519                                             .attr_count = CTA_EXPECT_MAX, },
1520         [IPCTNL_MSG_EXP_DELETE]         = { .call = ctnetlink_del_expect,
1521                                             .attr_count = CTA_EXPECT_MAX, },
1522 };
1523
1524 static struct nfnetlink_subsystem ctnl_subsys = {
1525         .name                           = "conntrack",
1526         .subsys_id                      = NFNL_SUBSYS_CTNETLINK,
1527         .cb_count                       = IPCTNL_MSG_MAX,
1528         .cb                             = ctnl_cb,
1529 };
1530
1531 static struct nfnetlink_subsystem ctnl_exp_subsys = {
1532         .name                           = "conntrack_expect",
1533         .subsys_id                      = NFNL_SUBSYS_CTNETLINK_EXP,
1534         .cb_count                       = IPCTNL_MSG_EXP_MAX,
1535         .cb                             = ctnl_exp_cb,
1536 };
1537
1538 MODULE_ALIAS("ip_conntrack_netlink");
1539 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK);
1540 MODULE_ALIAS_NFNL_SUBSYS(NFNL_SUBSYS_CTNETLINK_EXP);
1541
1542 static int __init ctnetlink_init(void)
1543 {
1544         int ret;
1545
1546         printk("ctnetlink v%s: registering with nfnetlink.\n", version);
1547         ret = nfnetlink_subsys_register(&ctnl_subsys);
1548         if (ret < 0) {
1549                 printk("ctnetlink_init: cannot register with nfnetlink.\n");
1550                 goto err_out;
1551         }
1552
1553         ret = nfnetlink_subsys_register(&ctnl_exp_subsys);
1554         if (ret < 0) {
1555                 printk("ctnetlink_init: cannot register exp with nfnetlink.\n");
1556                 goto err_unreg_subsys;
1557         }
1558
1559 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1560         ret = nf_conntrack_register_notifier(&ctnl_notifier);
1561         if (ret < 0) {
1562                 printk("ctnetlink_init: cannot register notifier.\n");
1563                 goto err_unreg_exp_subsys;
1564         }
1565
1566         ret = nf_conntrack_expect_register_notifier(&ctnl_notifier_exp);
1567         if (ret < 0) {
1568                 printk("ctnetlink_init: cannot expect register notifier.\n");
1569                 goto err_unreg_notifier;
1570         }
1571 #endif
1572
1573         return 0;
1574
1575 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1576 err_unreg_notifier:
1577         nf_conntrack_unregister_notifier(&ctnl_notifier);
1578 err_unreg_exp_subsys:
1579         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1580 #endif
1581 err_unreg_subsys:
1582         nfnetlink_subsys_unregister(&ctnl_subsys);
1583 err_out:
1584         return ret;
1585 }
1586
1587 static void __exit ctnetlink_exit(void)
1588 {
1589         printk("ctnetlink: unregistering from nfnetlink.\n");
1590
1591 #ifdef CONFIG_NF_CONNTRACK_EVENTS
1592         nf_conntrack_expect_unregister_notifier(&ctnl_notifier_exp);
1593         nf_conntrack_unregister_notifier(&ctnl_notifier);
1594 #endif
1595
1596         nfnetlink_subsys_unregister(&ctnl_exp_subsys);
1597         nfnetlink_subsys_unregister(&ctnl_subsys);
1598         return;
1599 }
1600
1601 module_init(ctnetlink_init);
1602 module_exit(ctnetlink_exit);